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Tom Rini10e47792018-05-06 17:58:06 -04001# SPDX-License-Identifier: GPL-2.0+
wdenkc6097192002-11-03 00:24:07 +00002#
Wolfgang Denk1234ce72013-06-21 10:22:36 +02003# (C) Copyright 2000 - 2013
wdenkc6097192002-11-03 00:24:07 +00004# Wolfgang Denk, DENX Software Engineering, wd@denx.de.
wdenkc6097192002-11-03 00:24:07 +00005
6Summary:
7========
8
wdenk24ee89b2002-11-03 17:56:27 +00009This directory contains the source code for U-Boot, a boot loader for
wdenkce4832c2004-10-17 21:12:06 +000010Embedded boards based on PowerPC, ARM, MIPS and several other
11processors, which can be installed in a boot ROM and used to
12initialize and test the hardware or to download and run application
13code.
wdenkc6097192002-11-03 00:24:07 +000014
15The development of U-Boot is closely related to Linux: some parts of
wdenk24ee89b2002-11-03 17:56:27 +000016the source code originate in the Linux source tree, we have some
17header files in common, and special provision has been made to
wdenkc6097192002-11-03 00:24:07 +000018support booting of Linux images.
19
20Some attention has been paid to make this software easily
21configurable and extendable. For instance, all monitor commands are
22implemented with the same call interface, so that it's very easy to
23add new commands. Also, instead of permanently adding rarely used
24code (for instance hardware test utilities) to the monitor, you can
25load and run it dynamically.
26
27
28Status:
29=======
30
31In general, all boards for which a configuration option exists in the
wdenk24ee89b2002-11-03 17:56:27 +000032Makefile have been tested to some extent and can be considered
wdenkc6097192002-11-03 00:24:07 +000033"working". In fact, many of them are used in production systems.
34
Robert P. J. Day076ed9b2015-12-19 07:16:10 -050035In case of problems see the CHANGELOG file to find out who contributed
36the specific port. In addition, there are various MAINTAINERS files
37scattered throughout the U-Boot source identifying the people or
38companies responsible for various boards and subsystems.
wdenkc6097192002-11-03 00:24:07 +000039
Robert P. J. Day076ed9b2015-12-19 07:16:10 -050040Note: As of August, 2010, there is no longer a CHANGELOG file in the
41actual U-Boot source tree; however, it can be created dynamically
42from the Git log using:
Robert P. J. Day974ed2f2012-11-14 02:03:20 +000043
44 make CHANGELOG
45
wdenkc6097192002-11-03 00:24:07 +000046
47Where to get help:
48==================
49
wdenk24ee89b2002-11-03 17:56:27 +000050In case you have questions about, problems with or contributions for
Robert P. J. Day076ed9b2015-12-19 07:16:10 -050051U-Boot, you should send a message to the U-Boot mailing list at
Peter Tyser8804a612008-09-10 09:18:34 -050052<u-boot@lists.denx.de>. There is also an archive of previous traffic
53on the mailing list - please search the archive before asking FAQ's.
54Please see http://lists.denx.de/pipermail/u-boot and
55http://dir.gmane.org/gmane.comp.boot-loaders.u-boot
wdenkc6097192002-11-03 00:24:07 +000056
57
Wolfgang Denkb240aef2008-03-26 10:40:12 +010058Where to get source code:
59=========================
60
Robert P. J. Day076ed9b2015-12-19 07:16:10 -050061The U-Boot source code is maintained in the Git repository at
Wolfgang Denkb240aef2008-03-26 10:40:12 +010062git://www.denx.de/git/u-boot.git ; you can browse it online at
63http://www.denx.de/cgi-bin/gitweb.cgi?p=u-boot.git;a=summary
64
65The "snapshot" links on this page allow you to download tarballs of
Marcel Ziswilerabd8dcb2008-07-09 08:17:15 +020066any version you might be interested in. Official releases are also
Wolfgang Denkb240aef2008-03-26 10:40:12 +010067available for FTP download from the ftp://ftp.denx.de/pub/u-boot/
68directory.
69
Anatolij Gustschin08337f32008-03-26 18:13:33 +010070Pre-built (and tested) images are available from
Wolfgang Denkb240aef2008-03-26 10:40:12 +010071ftp://ftp.denx.de/pub/u-boot/images/
72
73
wdenkc6097192002-11-03 00:24:07 +000074Where we come from:
75===================
76
77- start from 8xxrom sources
wdenk24ee89b2002-11-03 17:56:27 +000078- create PPCBoot project (http://sourceforge.net/projects/ppcboot)
wdenkc6097192002-11-03 00:24:07 +000079- clean up code
80- make it easier to add custom boards
81- make it possible to add other [PowerPC] CPUs
82- extend functions, especially:
83 * Provide extended interface to Linux boot loader
84 * S-Record download
85 * network boot
Simon Glassaaef3bf2019-08-01 09:47:14 -060086 * ATA disk / SCSI ... boot
wdenk24ee89b2002-11-03 17:56:27 +000087- create ARMBoot project (http://sourceforge.net/projects/armboot)
wdenkc6097192002-11-03 00:24:07 +000088- add other CPU families (starting with ARM)
wdenk24ee89b2002-11-03 17:56:27 +000089- create U-Boot project (http://sourceforge.net/projects/u-boot)
Magnus Liljaf3b287b2008-08-06 19:32:33 +020090- current project page: see http://www.denx.de/wiki/U-Boot
wdenk24ee89b2002-11-03 17:56:27 +000091
92
93Names and Spelling:
94===================
95
96The "official" name of this project is "Das U-Boot". The spelling
97"U-Boot" shall be used in all written text (documentation, comments
98in source files etc.). Example:
99
100 This is the README file for the U-Boot project.
101
102File names etc. shall be based on the string "u-boot". Examples:
103
104 include/asm-ppc/u-boot.h
105
106 #include <asm/u-boot.h>
107
108Variable names, preprocessor constants etc. shall be either based on
109the string "u_boot" or on "U_BOOT". Example:
wdenkc6097192002-11-03 00:24:07 +0000110
wdenk24ee89b2002-11-03 17:56:27 +0000111 U_BOOT_VERSION u_boot_logo
112 IH_OS_U_BOOT u_boot_hush_start
113
wdenkc6097192002-11-03 00:24:07 +0000114
wdenk7474aca2002-12-17 17:55:09 +0000115Versioning:
116===========
117
Thomas Webere89e6282010-09-28 08:06:25 +0200118Starting with the release in October 2008, the names of the releases
119were changed from numerical release numbers without deeper meaning
120into a time stamp based numbering. Regular releases are identified by
121names consisting of the calendar year and month of the release date.
122Additional fields (if present) indicate release candidates or bug fix
123releases in "stable" maintenance trees.
wdenk7474aca2002-12-17 17:55:09 +0000124
Thomas Webere89e6282010-09-28 08:06:25 +0200125Examples:
Wolfgang Denk092ae952011-10-26 10:21:21 +0000126 U-Boot v2009.11 - Release November 2009
Thomas Webere89e6282010-09-28 08:06:25 +0200127 U-Boot v2009.11.1 - Release 1 in version November 2009 stable tree
Jelle van der Waa30245ca2016-10-30 17:30:30 +0100128 U-Boot v2010.09-rc1 - Release candidate 1 for September 2010 release
wdenk7474aca2002-12-17 17:55:09 +0000129
130
wdenkc6097192002-11-03 00:24:07 +0000131Directory Hierarchy:
132====================
133
Peter Tysere4d1abc2010-04-12 22:28:21 -0500134/arch Architecture specific files
Masahiro Yamadaef6ebff2014-03-07 18:02:02 +0900135 /arc Files generic to ARC architecture
Peter Tysere4d1abc2010-04-12 22:28:21 -0500136 /arm Files generic to ARM architecture
Peter Tysere4d1abc2010-04-12 22:28:21 -0500137 /m68k Files generic to m68k architecture
Peter Tysere4d1abc2010-04-12 22:28:21 -0500138 /microblaze Files generic to microblaze architecture
Peter Tysere4d1abc2010-04-12 22:28:21 -0500139 /mips Files generic to MIPS architecture
Macpaul Lin1cac36e2011-10-19 20:41:11 +0000140 /nds32 Files generic to NDS32 architecture
Peter Tysere4d1abc2010-04-12 22:28:21 -0500141 /nios2 Files generic to Altera NIOS2 architecture
Robert P. J. Daya269c932013-09-15 18:34:15 -0400142 /openrisc Files generic to OpenRISC architecture
Stefan Roese88fbf932010-04-15 16:07:28 +0200143 /powerpc Files generic to PowerPC architecture
Rick Chend7e6f922017-12-26 13:55:59 +0800144 /riscv Files generic to RISC-V architecture
Robert P. J. Day076ed9b2015-12-19 07:16:10 -0500145 /sandbox Files generic to HW-independent "sandbox"
Peter Tysere4d1abc2010-04-12 22:28:21 -0500146 /sh Files generic to SH architecture
Robert P. J. Daya269c932013-09-15 18:34:15 -0400147 /x86 Files generic to x86 architecture
Peter Tysere4d1abc2010-04-12 22:28:21 -0500148/api Machine/arch independent API for external apps
149/board Board dependent files
Xu Ziyuanfb1f9392016-08-26 19:54:49 +0800150/cmd U-Boot commands functions
Peter Tysere4d1abc2010-04-12 22:28:21 -0500151/common Misc architecture independent functions
Robert P. J. Day076ed9b2015-12-19 07:16:10 -0500152/configs Board default configuration files
Peter Tysere4d1abc2010-04-12 22:28:21 -0500153/disk Code for disk drive partition handling
154/doc Documentation (don't expect too much)
155/drivers Commonly used device drivers
Robert P. J. Daya269c932013-09-15 18:34:15 -0400156/dts Contains Makefile for building internal U-Boot fdt.
Peter Tysere4d1abc2010-04-12 22:28:21 -0500157/examples Example code for standalone applications, etc.
158/fs Filesystem code (cramfs, ext2, jffs2, etc.)
159/include Header Files
Robert P. J. Day076ed9b2015-12-19 07:16:10 -0500160/lib Library routines generic to all architectures
161/Licenses Various license files
Peter Tysere4d1abc2010-04-12 22:28:21 -0500162/net Networking code
163/post Power On Self Test
Robert P. J. Day076ed9b2015-12-19 07:16:10 -0500164/scripts Various build scripts and Makefiles
165/test Various unit test files
Peter Tysere4d1abc2010-04-12 22:28:21 -0500166/tools Tools to build S-Record or U-Boot images, etc.
wdenkc6097192002-11-03 00:24:07 +0000167
wdenkc6097192002-11-03 00:24:07 +0000168Software Configuration:
169=======================
170
171Configuration is usually done using C preprocessor defines; the
172rationale behind that is to avoid dead code whenever possible.
173
174There are two classes of configuration variables:
175
176* Configuration _OPTIONS_:
177 These are selectable by the user and have names beginning with
178 "CONFIG_".
179
180* Configuration _SETTINGS_:
181 These depend on the hardware etc. and should not be meddled with if
182 you don't know what you're doing; they have names beginning with
Jean-Christophe PLAGNIOL-VILLARD03836942008-10-16 15:01:15 +0200183 "CONFIG_SYS_".
wdenkc6097192002-11-03 00:24:07 +0000184
Robert P. J. Day076ed9b2015-12-19 07:16:10 -0500185Previously, all configuration was done by hand, which involved creating
186symbolic links and editing configuration files manually. More recently,
187U-Boot has added the Kbuild infrastructure used by the Linux kernel,
188allowing you to use the "make menuconfig" command to configure your
189build.
wdenkc6097192002-11-03 00:24:07 +0000190
191
192Selection of Processor Architecture and Board Type:
193---------------------------------------------------
194
195For all supported boards there are ready-to-use default
Holger Freyther7ba4e572014-08-04 09:26:05 +0200196configurations available; just type "make <board_name>_defconfig".
wdenkc6097192002-11-03 00:24:07 +0000197
198Example: For a TQM823L module type:
199
200 cd u-boot
Holger Freyther7ba4e572014-08-04 09:26:05 +0200201 make TQM823L_defconfig
wdenkc6097192002-11-03 00:24:07 +0000202
Robert P. J. Day076ed9b2015-12-19 07:16:10 -0500203Note: If you're looking for the default configuration file for a board
204you're sure used to be there but is now missing, check the file
205doc/README.scrapyard for a list of no longer supported boards.
wdenkc6097192002-11-03 00:24:07 +0000206
Simon Glass53552c92014-03-22 17:12:59 -0600207Sandbox Environment:
208--------------------
209
210U-Boot can be built natively to run on a Linux host using the 'sandbox'
211board. This allows feature development which is not board- or architecture-
212specific to be undertaken on a native platform. The sandbox is also used to
213run some of U-Boot's tests.
214
Keerthyfa002552019-07-29 13:52:04 +0530215See doc/arch/index.rst for more details.
Simon Glass53552c92014-03-22 17:12:59 -0600216
217
Simon Glassd8711af2015-03-03 08:03:00 -0700218Board Initialisation Flow:
219--------------------------
220
221This is the intended start-up flow for boards. This should apply for both
Robert P. J. Day076ed9b2015-12-19 07:16:10 -0500222SPL and U-Boot proper (i.e. they both follow the same rules).
223
224Note: "SPL" stands for "Secondary Program Loader," which is explained in
225more detail later in this file.
226
227At present, SPL mostly uses a separate code path, but the function names
228and roles of each function are the same. Some boards or architectures
229may not conform to this. At least most ARM boards which use
230CONFIG_SPL_FRAMEWORK conform to this.
Simon Glassd8711af2015-03-03 08:03:00 -0700231
Robert P. J. Day076ed9b2015-12-19 07:16:10 -0500232Execution typically starts with an architecture-specific (and possibly
233CPU-specific) start.S file, such as:
234
235 - arch/arm/cpu/armv7/start.S
236 - arch/powerpc/cpu/mpc83xx/start.S
237 - arch/mips/cpu/start.S
238
239and so on. From there, three functions are called; the purpose and
240limitations of each of these functions are described below.
Simon Glassd8711af2015-03-03 08:03:00 -0700241
242lowlevel_init():
243 - purpose: essential init to permit execution to reach board_init_f()
244 - no global_data or BSS
245 - there is no stack (ARMv7 may have one but it will soon be removed)
246 - must not set up SDRAM or use console
247 - must only do the bare minimum to allow execution to continue to
248 board_init_f()
249 - this is almost never needed
250 - return normally from this function
251
252board_init_f():
253 - purpose: set up the machine ready for running board_init_r():
254 i.e. SDRAM and serial UART
255 - global_data is available
256 - stack is in SRAM
257 - BSS is not available, so you cannot use global/static variables,
258 only stack variables and global_data
259
260 Non-SPL-specific notes:
261 - dram_init() is called to set up DRAM. If already done in SPL this
262 can do nothing
263
264 SPL-specific notes:
265 - you can override the entire board_init_f() function with your own
266 version as needed.
267 - preloader_console_init() can be called here in extremis
268 - should set up SDRAM, and anything needed to make the UART work
269 - these is no need to clear BSS, it will be done by crt0.S
270 - must return normally from this function (don't call board_init_r()
271 directly)
272
273Here the BSS is cleared. For SPL, if CONFIG_SPL_STACK_R is defined, then at
274this point the stack and global_data are relocated to below
275CONFIG_SPL_STACK_R_ADDR. For non-SPL, U-Boot is relocated to run at the top of
276memory.
277
278board_init_r():
279 - purpose: main execution, common code
280 - global_data is available
281 - SDRAM is available
282 - BSS is available, all static/global variables can be used
283 - execution eventually continues to main_loop()
284
285 Non-SPL-specific notes:
286 - U-Boot is relocated to the top of memory and is now running from
287 there.
288
289 SPL-specific notes:
290 - stack is optionally in SDRAM, if CONFIG_SPL_STACK_R is defined and
291 CONFIG_SPL_STACK_R_ADDR points into SDRAM
292 - preloader_console_init() can be called here - typically this is
Ley Foon Tan48fcc4a2017-05-03 17:13:32 +0800293 done by selecting CONFIG_SPL_BOARD_INIT and then supplying a
Simon Glassd8711af2015-03-03 08:03:00 -0700294 spl_board_init() function containing this call
295 - loads U-Boot or (in falcon mode) Linux
296
297
298
wdenkc6097192002-11-03 00:24:07 +0000299Configuration Options:
300----------------------
301
302Configuration depends on the combination of board and CPU type; all
303such information is kept in a configuration file
304"include/configs/<board_name>.h".
305
306Example: For a TQM823L module, all configuration settings are in
307"include/configs/TQM823L.h".
308
309
wdenk1272e232002-11-10 22:06:23 +0000310Many of the options are named exactly as the corresponding Linux
311kernel configuration options. The intention is to make it easier to
312build a config tool - later.
313
Ashish Kumar11234062017-08-11 11:09:14 +0530314- ARM Platform Bus Type(CCI):
315 CoreLink Cache Coherent Interconnect (CCI) is ARM BUS which
316 provides full cache coherency between two clusters of multi-core
317 CPUs and I/O coherency for devices and I/O masters
318
319 CONFIG_SYS_FSL_HAS_CCI400
320
321 Defined For SoC that has cache coherent interconnect
322 CCN-400
wdenk1272e232002-11-10 22:06:23 +0000323
Ashish Kumar97393d62017-08-18 10:54:36 +0530324 CONFIG_SYS_FSL_HAS_CCN504
325
326 Defined for SoC that has cache coherent interconnect CCN-504
327
wdenkc6097192002-11-03 00:24:07 +0000328The following options need to be configured:
329
Kim Phillips203fee32007-08-10 13:28:25 -0500330- CPU Type: Define exactly one, e.g. CONFIG_MPC85XX.
wdenkc6097192002-11-03 00:24:07 +0000331
Kim Phillips203fee32007-08-10 13:28:25 -0500332- Board Type: Define exactly one, e.g. CONFIG_MPC8540ADS.
Wolfgang Denk994ad962006-10-24 14:42:37 +0200333
Kumar Galaf4fb90f2011-02-18 05:40:54 -0600334- 85xx CPU Options:
York Sun2394a0f2012-10-08 07:44:30 +0000335 CONFIG_SYS_PPC64
336
337 Specifies that the core is a 64-bit PowerPC implementation (implements
338 the "64" category of the Power ISA). This is necessary for ePAPR
339 compliance, among other possible reasons.
340
Kumar Galaf4fb90f2011-02-18 05:40:54 -0600341 CONFIG_SYS_FSL_TBCLK_DIV
342
343 Defines the core time base clock divider ratio compared to the
344 system clock. On most PQ3 devices this is 8, on newer QorIQ
345 devices it can be 16 or 32. The ratio varies from SoC to Soc.
346
Kumar Gala179b1b22011-05-20 00:39:21 -0500347 CONFIG_SYS_FSL_PCIE_COMPAT
348
349 Defines the string to utilize when trying to match PCIe device
350 tree nodes for the given platform.
351
Scott Wood80806962012-08-14 10:14:53 +0000352 CONFIG_SYS_FSL_ERRATUM_A004510
353
354 Enables a workaround for erratum A004510. If set,
355 then CONFIG_SYS_FSL_ERRATUM_A004510_SVR_REV and
356 CONFIG_SYS_FSL_CORENET_SNOOPVEC_COREONLY must be set.
357
358 CONFIG_SYS_FSL_ERRATUM_A004510_SVR_REV
359 CONFIG_SYS_FSL_ERRATUM_A004510_SVR_REV2 (optional)
360
361 Defines one or two SoC revisions (low 8 bits of SVR)
362 for which the A004510 workaround should be applied.
363
364 The rest of SVR is either not relevant to the decision
365 of whether the erratum is present (e.g. p2040 versus
366 p2041) or is implied by the build target, which controls
367 whether CONFIG_SYS_FSL_ERRATUM_A004510 is set.
368
369 See Freescale App Note 4493 for more information about
370 this erratum.
371
Prabhakar Kushwahad324f472013-04-16 13:27:44 +0530372 CONFIG_A003399_NOR_WORKAROUND
373 Enables a workaround for IFC erratum A003399. It is only
Jeremiah Mahler03f930c2015-01-04 18:56:50 -0800374 required during NOR boot.
Prabhakar Kushwahad324f472013-04-16 13:27:44 +0530375
Prabhakar Kushwahac4c10d12014-10-29 22:33:09 +0530376 CONFIG_A008044_WORKAROUND
377 Enables a workaround for T1040/T1042 erratum A008044. It is only
Jeremiah Mahler03f930c2015-01-04 18:56:50 -0800378 required during NAND boot and valid for Rev 1.0 SoC revision
Prabhakar Kushwahac4c10d12014-10-29 22:33:09 +0530379
Scott Wood80806962012-08-14 10:14:53 +0000380 CONFIG_SYS_FSL_CORENET_SNOOPVEC_COREONLY
381
382 This is the value to write into CCSR offset 0x18600
383 according to the A004510 workaround.
384
Priyanka Jainc73b9032013-07-02 09:21:04 +0530385 CONFIG_SYS_FSL_DSP_DDR_ADDR
386 This value denotes start offset of DDR memory which is
387 connected exclusively to the DSP cores.
388
Priyanka Jainf81e8b22013-04-04 09:31:54 +0530389 CONFIG_SYS_FSL_DSP_M2_RAM_ADDR
390 This value denotes start offset of M2 memory
391 which is directly connected to the DSP core.
392
Priyanka Jainc73b9032013-07-02 09:21:04 +0530393 CONFIG_SYS_FSL_DSP_M3_RAM_ADDR
394 This value denotes start offset of M3 memory which is directly
395 connected to the DSP core.
396
Priyanka Jainf81e8b22013-04-04 09:31:54 +0530397 CONFIG_SYS_FSL_DSP_CCSRBAR_DEFAULT
398 This value denotes start offset of DSP CCSR space.
399
Priyanka Jaine9dcaa82013-12-17 14:25:52 +0530400 CONFIG_SYS_FSL_SINGLE_SOURCE_CLK
401 Single Source Clock is clocking mode present in some of FSL SoC's.
402 In this mode, a single differential clock is used to supply
403 clocks to the sysclock, ddrclock and usbclock.
404
Aneesh Bansal8bcbc272014-03-18 23:40:26 +0530405 CONFIG_SYS_CPC_REINIT_F
406 This CONFIG is defined when the CPC is configured as SRAM at the
Bin Meng75574052016-02-05 19:30:11 -0800407 time of U-Boot entry and is required to be re-initialized.
Aneesh Bansal8bcbc272014-03-18 23:40:26 +0530408
Tang Yuantiana7364af2014-04-17 15:33:46 +0800409 CONFIG_DEEP_SLEEP
Jeremiah Mahler03f930c2015-01-04 18:56:50 -0800410 Indicates this SoC supports deep sleep feature. If deep sleep is
Tang Yuantiana7364af2014-04-17 15:33:46 +0800411 supported, core will start to execute uboot when wakes up.
412
Daniel Schwierzeckd8a49ca2012-04-02 02:57:56 +0000413- Generic CPU options:
414 CONFIG_SYS_BIG_ENDIAN, CONFIG_SYS_LITTLE_ENDIAN
415
416 Defines the endianess of the CPU. Implementation of those
417 values is arch specific.
418
York Sunf0626592013-09-30 09:22:09 -0700419 CONFIG_SYS_FSL_DDR
420 Freescale DDR driver in use. This type of DDR controller is
421 found in mpc83xx, mpc85xx, mpc86xx as well as some ARM core
422 SoCs.
423
424 CONFIG_SYS_FSL_DDR_ADDR
425 Freescale DDR memory-mapped register base.
426
427 CONFIG_SYS_FSL_DDR_EMU
428 Specify emulator support for DDR. Some DDR features such as
429 deskew training are not available.
430
431 CONFIG_SYS_FSL_DDRC_GEN1
432 Freescale DDR1 controller.
433
434 CONFIG_SYS_FSL_DDRC_GEN2
435 Freescale DDR2 controller.
436
437 CONFIG_SYS_FSL_DDRC_GEN3
438 Freescale DDR3 controller.
439
York Sun2896cb72014-03-27 17:54:47 -0700440 CONFIG_SYS_FSL_DDRC_GEN4
441 Freescale DDR4 controller.
442
York Sun461c9392013-09-30 14:20:51 -0700443 CONFIG_SYS_FSL_DDRC_ARM_GEN3
444 Freescale DDR3 controller for ARM-based SoCs.
445
York Sunf0626592013-09-30 09:22:09 -0700446 CONFIG_SYS_FSL_DDR1
447 Board config to use DDR1. It can be enabled for SoCs with
448 Freescale DDR1 or DDR2 controllers, depending on the board
449 implemetation.
450
451 CONFIG_SYS_FSL_DDR2
Robert P. J. Day8d56db92016-07-15 13:44:45 -0400452 Board config to use DDR2. It can be enabled for SoCs with
York Sunf0626592013-09-30 09:22:09 -0700453 Freescale DDR2 or DDR3 controllers, depending on the board
454 implementation.
455
456 CONFIG_SYS_FSL_DDR3
457 Board config to use DDR3. It can be enabled for SoCs with
York Sun2896cb72014-03-27 17:54:47 -0700458 Freescale DDR3 or DDR3L controllers.
459
460 CONFIG_SYS_FSL_DDR3L
461 Board config to use DDR3L. It can be enabled for SoCs with
462 DDR3L controllers.
463
464 CONFIG_SYS_FSL_DDR4
465 Board config to use DDR4. It can be enabled for SoCs with
466 DDR4 controllers.
York Sunf0626592013-09-30 09:22:09 -0700467
Prabhakar Kushwaha62908c22014-01-18 12:28:30 +0530468 CONFIG_SYS_FSL_IFC_BE
469 Defines the IFC controller register space as Big Endian
470
471 CONFIG_SYS_FSL_IFC_LE
472 Defines the IFC controller register space as Little Endian
473
Prabhakar Kushwaha3c48f582017-02-02 15:01:26 +0530474 CONFIG_SYS_FSL_IFC_CLK_DIV
475 Defines divider of platform clock(clock input to IFC controller).
476
Prabhakar Kushwahabedc5622017-02-02 15:02:00 +0530477 CONFIG_SYS_FSL_LBC_CLK_DIV
478 Defines divider of platform clock(clock input to eLBC controller).
479
Prabhakar Kushwaha950f2f72014-01-13 11:28:04 +0530480 CONFIG_SYS_FSL_PBL_PBI
481 It enables addition of RCW (Power on reset configuration) in built image.
482 Please refer doc/README.pblimage for more details
483
484 CONFIG_SYS_FSL_PBL_RCW
485 It adds PBI(pre-boot instructions) commands in u-boot build image.
486 PBI commands can be used to configure SoC before it starts the execution.
487 Please refer doc/README.pblimage for more details
488
York Sun29647ab2014-02-10 13:59:42 -0800489 CONFIG_SYS_FSL_DDR_BE
490 Defines the DDR controller register space as Big Endian
491
492 CONFIG_SYS_FSL_DDR_LE
493 Defines the DDR controller register space as Little Endian
494
York Sun3a0916d2014-02-10 13:59:43 -0800495 CONFIG_SYS_FSL_DDR_SDRAM_BASE_PHY
496 Physical address from the view of DDR controllers. It is the
497 same as CONFIG_SYS_DDR_SDRAM_BASE for all Power SoCs. But
498 it could be different for ARM SoCs.
499
York Sunc459ae62014-02-10 13:59:44 -0800500 CONFIG_SYS_FSL_DDR_INTLV_256B
501 DDR controller interleaving on 256-byte. This is a special
502 interleaving mode, handled by Dickens for Freescale layerscape
503 SoCs with ARM core.
504
York Sun79a779b2014-08-01 15:51:00 -0700505 CONFIG_SYS_FSL_DDR_MAIN_NUM_CTRLS
506 Number of controllers used as main memory.
507
508 CONFIG_SYS_FSL_OTHER_DDR_NUM_CTRLS
509 Number of controllers used for other than main memory.
510
Prabhakar Kushwaha122bcfd2015-11-09 16:42:07 +0530511 CONFIG_SYS_FSL_HAS_DP_DDR
512 Defines the SoC has DP-DDR used for DPAA.
513
Ruchika Guptabb7143b2014-09-09 11:50:31 +0530514 CONFIG_SYS_FSL_SEC_BE
515 Defines the SEC controller register space as Big Endian
516
517 CONFIG_SYS_FSL_SEC_LE
518 Defines the SEC controller register space as Little Endian
519
Daniel Schwierzeckd52a6232011-07-27 13:22:39 +0200520- MIPS CPU options:
521 CONFIG_SYS_INIT_SP_OFFSET
522
523 Offset relative to CONFIG_SYS_SDRAM_BASE for initial stack
524 pointer. This is needed for the temporary stack before
525 relocation.
526
Daniel Schwierzeckd52a6232011-07-27 13:22:39 +0200527 CONFIG_XWAY_SWAP_BYTES
528
529 Enable compilation of tools/xway-swap-bytes needed for Lantiq
530 XWAY SoCs for booting from NOR flash. The U-Boot image needs to
531 be swapped if a flash programmer is used.
532
Christian Riesch48c2d6d2012-02-02 00:44:39 +0000533- ARM options:
534 CONFIG_SYS_EXCEPTION_VECTORS_HIGH
535
536 Select high exception vectors of the ARM core, e.g., do not
537 clear the V bit of the c1 register of CP15.
538
York Sun77a10972015-03-20 19:28:08 -0700539 COUNTER_FREQUENCY
540 Generic timer clock source frequency.
541
542 COUNTER_FREQUENCY_REAL
543 Generic timer clock source frequency if the real clock is
544 different from COUNTER_FREQUENCY, and can only be determined
545 at run time.
546
Stephen Warren8d1fb312015-01-19 16:25:52 -0700547- Tegra SoC options:
548 CONFIG_TEGRA_SUPPORT_NON_SECURE
549
550 Support executing U-Boot in non-secure (NS) mode. Certain
551 impossible actions will be skipped if the CPU is in NS mode,
552 such as ARM architectural timer initialization.
553
wdenk9b7f3842003-10-09 20:09:04 +0000554- Linux Kernel Interface:
wdenkc6097192002-11-03 00:24:07 +0000555 CONFIG_CLOCKS_IN_MHZ
556
557 U-Boot stores all clock information in Hz
558 internally. For binary compatibility with older Linux
559 kernels (which expect the clocks passed in the
560 bd_info data to be in MHz) the environment variable
561 "clocks_in_mhz" can be defined so that U-Boot
562 converts clock data to MHZ before passing it to the
563 Linux kernel.
wdenkc6097192002-11-03 00:24:07 +0000564 When CONFIG_CLOCKS_IN_MHZ is defined, a definition of
Wolfgang Denkb240aef2008-03-26 10:40:12 +0100565 "clocks_in_mhz=1" is automatically included in the
wdenkc6097192002-11-03 00:24:07 +0000566 default environment.
567
wdenk9b7f3842003-10-09 20:09:04 +0000568 CONFIG_MEMSIZE_IN_BYTES [relevant for MIPS only]
569
Jeremiah Mahler03f930c2015-01-04 18:56:50 -0800570 When transferring memsize parameter to Linux, some versions
wdenk9b7f3842003-10-09 20:09:04 +0000571 expect it to be in bytes, others in MB.
572 Define CONFIG_MEMSIZE_IN_BYTES to make it in bytes.
573
Gerald Van Barenfcd91bb2008-06-03 20:34:45 -0400574 CONFIG_OF_LIBFDT
Wolfgang Denk27a5b0b2005-10-13 01:45:54 +0200575
576 New kernel versions are expecting firmware settings to be
Gerald Van Barend6abef42007-03-31 12:23:51 -0400577 passed using flattened device trees (based on open firmware
578 concepts).
579
580 CONFIG_OF_LIBFDT
581 * New libfdt-based support
582 * Adds the "fdt" command
Kim Phillips9b46eb62007-08-10 14:34:14 -0500583 * The bootm command automatically updates the fdt
Gerald Van Barend6abef42007-03-31 12:23:51 -0400584
Wolfgang Denk27a5b0b2005-10-13 01:45:54 +0200585 OF_TBCLK - The timebase frequency.
Kumar Galae40c2b52006-01-11 13:59:02 -0600586 OF_STDOUT_PATH - The path to the console device
Wolfgang Denk27a5b0b2005-10-13 01:45:54 +0200587
Marcel Ziswilerabd8dcb2008-07-09 08:17:15 +0200588 boards with QUICC Engines require OF_QE to set UCC MAC
589 addresses
Kim Phillips9b46eb62007-08-10 14:34:14 -0500590
Kumar Gala1e26aa52006-01-11 13:54:17 -0600591 CONFIG_OF_BOARD_SETUP
592
593 Board code has addition modification that it wants to make
594 to the flat device tree before handing it off to the kernel
wdenkda04a8b2004-08-02 23:22:59 +0000595
Simon Glass6c0be912014-10-23 18:58:54 -0600596 CONFIG_OF_SYSTEM_SETUP
597
598 Other code has addition modification that it wants to make
599 to the flat device tree before handing it off to the kernel.
600 This causes ft_system_setup() to be called before booting
601 the kernel.
602
Heiko Schocherffb293a2009-09-23 07:56:08 +0200603 CONFIG_OF_IDE_FIXUP
604
605 U-Boot can detect if an IDE device is present or not.
606 If not, and this new config option is activated, U-Boot
607 removes the ATA node from the DTS before booting Linux,
608 so the Linux IDE driver does not probe the device and
609 crash. This is needed for buggy hardware (uc101) where
610 no pull down resistor is connected to the signal IDE5V_DD7.
611
Igor Grinberg06890672011-07-14 05:45:07 +0000612 CONFIG_MACH_TYPE [relevant for ARM only][mandatory]
613
614 This setting is mandatory for all boards that have only one
615 machine type and must be used to specify the machine type
616 number as it appears in the ARM machine registry
617 (see http://www.arm.linux.org.uk/developer/machines/).
618 Only boards that have multiple machine types supported
619 in a single configuration file and the machine type is
620 runtime discoverable, do not have to use this setting.
621
Niklaus Giger0ab978d2008-11-03 22:13:47 +0100622- vxWorks boot parameters:
623
624 bootvx constructs a valid bootline using the following
Bin Mengfb694b92015-10-07 20:19:17 -0700625 environments variables: bootdev, bootfile, ipaddr, netmask,
626 serverip, gatewayip, hostname, othbootargs.
Niklaus Giger0ab978d2008-11-03 22:13:47 +0100627 It loads the vxWorks image pointed bootfile.
628
Niklaus Giger0ab978d2008-11-03 22:13:47 +0100629 Note: If a "bootargs" environment is defined, it will overwride
630 the defaults discussed just above.
631
Aneesh V960f5c02011-06-16 23:30:47 +0000632- Cache Configuration:
Aneesh V960f5c02011-06-16 23:30:47 +0000633 CONFIG_SYS_L2CACHE_OFF- Do not enable L2 cache in U-Boot
634
Aneesh V686a0752011-06-16 23:30:51 +0000635- Cache Configuration for ARM:
636 CONFIG_SYS_L2_PL310 - Enable support for ARM PL310 L2 cache
637 controller
638 CONFIG_SYS_PL310_BASE - Physical base address of PL310
639 controller register space
640
wdenkda04a8b2004-08-02 23:22:59 +0000641- Serial Ports:
Andreas Engel0813b122008-09-08 14:30:53 +0200642 CONFIG_PL010_SERIAL
wdenkda04a8b2004-08-02 23:22:59 +0000643
644 Define this if you want support for Amba PrimeCell PL010 UARTs.
645
Andreas Engel0813b122008-09-08 14:30:53 +0200646 CONFIG_PL011_SERIAL
wdenkda04a8b2004-08-02 23:22:59 +0000647
648 Define this if you want support for Amba PrimeCell PL011 UARTs.
649
650 CONFIG_PL011_CLOCK
651
652 If you have Amba PrimeCell PL011 UARTs, set this variable to
653 the clock speed of the UARTs.
654
655 CONFIG_PL01x_PORTS
656
657 If you have Amba PrimeCell PL010 or PL011 UARTs on your board,
658 define this to a list of base addresses for each (supported)
659 port. See e.g. include/configs/versatile.h
660
Karicheri, Muralidharancbc08882014-04-09 15:38:46 -0400661 CONFIG_SERIAL_HW_FLOW_CONTROL
662
663 Define this variable to enable hw flow control in serial driver.
664 Current user of this option is drivers/serial/nsl16550.c driver
wdenkda04a8b2004-08-02 23:22:59 +0000665
wdenkc6097192002-11-03 00:24:07 +0000666- Console Baudrate:
667 CONFIG_BAUDRATE - in bps
668 Select one of the baudrates listed in
Jean-Christophe PLAGNIOL-VILLARD03836942008-10-16 15:01:15 +0200669 CONFIG_SYS_BAUDRATE_TABLE, see below.
wdenkc6097192002-11-03 00:24:07 +0000670
wdenkc6097192002-11-03 00:24:07 +0000671- Autoboot Command:
672 CONFIG_BOOTCOMMAND
673 Only needed when CONFIG_BOOTDELAY is enabled;
674 define a command string that is automatically executed
675 when no character is read on the console interface
676 within "Boot Delay" after reset.
677
wdenkc6097192002-11-03 00:24:07 +0000678 CONFIG_RAMBOOT and CONFIG_NFSBOOT
wdenk4a5c8a72003-03-06 00:02:04 +0000679 The value of these goes into the environment as
680 "ramboot" and "nfsboot" respectively, and can be used
681 as a convenience, when switching between booting from
Marcel Ziswilerabd8dcb2008-07-09 08:17:15 +0200682 RAM and NFS.
wdenkc6097192002-11-03 00:24:07 +0000683
wdenkc6097192002-11-03 00:24:07 +0000684- Serial Download Echo Mode:
685 CONFIG_LOADS_ECHO
686 If defined to 1, all characters received during a
687 serial download (using the "loads" command) are
688 echoed back. This might be needed by some terminal
689 emulations (like "cu"), but may as well just take
690 time on others. This setting #define's the initial
691 value of the "loads_echo" environment variable.
692
Jon Loeligerc1da5c92007-06-11 19:03:39 -0500693- Kgdb Serial Baudrate: (if CONFIG_CMD_KGDB is defined)
wdenkc6097192002-11-03 00:24:07 +0000694 CONFIG_KGDB_BAUDRATE
695 Select one of the baudrates listed in
Jean-Christophe PLAGNIOL-VILLARD03836942008-10-16 15:01:15 +0200696 CONFIG_SYS_BAUDRATE_TABLE, see below.
wdenkc6097192002-11-03 00:24:07 +0000697
Simon Glassaa34ef22016-03-13 19:07:28 -0600698- Removal of commands
699 If no commands are needed to boot, you can disable
700 CONFIG_CMDLINE to remove them. In this case, the command line
701 will not be available, and when U-Boot wants to execute the
702 boot command (on start-up) it will call board_run_command()
703 instead. This can reduce image size significantly for very
704 simple boot procedures.
705
Wolfgang Denk2aceea12013-03-23 23:50:31 +0000706- Regular expression support:
707 CONFIG_REGEX
Wolfgang Denkec7fbf52013-10-04 17:43:24 +0200708 If this variable is defined, U-Boot is linked against
709 the SLRE (Super Light Regular Expression) library,
710 which adds regex support to some commands, as for
711 example "env grep" and "setexpr".
Wolfgang Denk2aceea12013-03-23 23:50:31 +0000712
Simon Glass3d686442011-10-15 05:48:20 +0000713- Device tree:
714 CONFIG_OF_CONTROL
715 If this variable is defined, U-Boot will use a device tree
716 to configure its devices, instead of relying on statically
717 compiled #defines in the board file. This option is
718 experimental and only available on a few boards. The device
719 tree is available in the global data as gd->fdt_blob.
720
Simon Glass5cb34db2011-10-24 19:15:31 +0000721 U-Boot needs to get its device tree from somewhere. This can
Alex Deymo5b661ec2017-04-02 01:25:20 -0700722 be done using one of the three options below:
Simon Glass38d6b8d2011-10-15 05:48:21 +0000723
724 CONFIG_OF_EMBED
725 If this variable is defined, U-Boot will embed a device tree
726 binary in its image. This device tree file should be in the
727 board directory and called <soc>-<board>.dts. The binary file
728 is then picked up in board_init_f() and made available through
Nobuhiro Iwamatsu1f17f192017-08-26 07:34:14 +0900729 the global data structure as gd->fdt_blob.
Simon Glass3d686442011-10-15 05:48:20 +0000730
Simon Glass5cb34db2011-10-24 19:15:31 +0000731 CONFIG_OF_SEPARATE
732 If this variable is defined, U-Boot will build a device tree
733 binary. It will be called u-boot.dtb. Architecture-specific
734 code will locate it at run-time. Generally this works by:
735
736 cat u-boot.bin u-boot.dtb >image.bin
737
738 and in fact, U-Boot does this for you, creating a file called
739 u-boot-dtb.bin which is useful in the common case. You can
740 still use the individual files if you need something more
741 exotic.
742
Alex Deymo5b661ec2017-04-02 01:25:20 -0700743 CONFIG_OF_BOARD
744 If this variable is defined, U-Boot will use the device tree
745 provided by the board at runtime instead of embedding one with
746 the image. Only boards defining board_fdt_blob_setup() support
747 this option (see include/fdtdec.h file).
748
wdenkc6097192002-11-03 00:24:07 +0000749- Watchdog:
750 CONFIG_WATCHDOG
751 If this variable is defined, it enables watchdog
Detlev Zundel6aa4d7b2011-04-27 05:25:59 +0000752 support for the SoC. There must be support in the SoC
Christophe Leroy069fa832017-07-06 10:23:22 +0200753 specific code for a watchdog. For the 8xx
754 CPUs, the SIU Watchdog feature is enabled in the SYPCR
755 register. When supported for a specific SoC is
756 available, then no further board specific code should
757 be needed to use it.
Detlev Zundel6aa4d7b2011-04-27 05:25:59 +0000758
759 CONFIG_HW_WATCHDOG
760 When using a watchdog circuitry external to the used
761 SoC, then define this variable and provide board
762 specific code for the "hw_watchdog_reset" function.
wdenkc6097192002-11-03 00:24:07 +0000763
764- Real-Time Clock:
765
Jon Loeligerc1da5c92007-06-11 19:03:39 -0500766 When CONFIG_CMD_DATE is selected, the type of the RTC
wdenkc6097192002-11-03 00:24:07 +0000767 has to be selected, too. Define exactly one of the
768 following options:
769
wdenkc6097192002-11-03 00:24:07 +0000770 CONFIG_RTC_PCF8563 - use Philips PCF8563 RTC
Fabio Estevam3f8d1782011-10-24 06:44:15 +0000771 CONFIG_RTC_MC13XXX - use MC13783 or MC13892 RTC
wdenkc6097192002-11-03 00:24:07 +0000772 CONFIG_RTC_MC146818 - use MC146818 RTC
wdenk1fe2c702003-03-06 21:55:29 +0000773 CONFIG_RTC_DS1307 - use Maxim, Inc. DS1307 RTC
wdenkc6097192002-11-03 00:24:07 +0000774 CONFIG_RTC_DS1337 - use Maxim, Inc. DS1337 RTC
wdenk0893c472003-05-20 14:25:27 +0000775 CONFIG_RTC_DS1338 - use Maxim, Inc. DS1338 RTC
Markus Niebel90491f22014-07-21 11:06:16 +0200776 CONFIG_RTC_DS1339 - use Maxim, Inc. DS1339 RTC
wdenkef5fe752003-03-12 10:41:04 +0000777 CONFIG_RTC_DS164x - use Dallas DS164x RTC
Tor Krillb27939b2008-03-15 15:40:26 +0100778 CONFIG_RTC_ISL1208 - use Intersil ISL1208 RTC
wdenkaeba06f2004-06-09 17:34:58 +0000779 CONFIG_RTC_MAX6900 - use Maxim, Inc. MAX6900 RTC
Chris Packham2d3ac512017-05-30 12:03:33 +1200780 CONFIG_RTC_DS1337_NOOSC - Turn off the OSC output for DS1337
Heiko Schocher1f1b7012011-03-28 09:24:22 +0200781 CONFIG_SYS_RV3029_TCR - enable trickle charger on
782 RV3029 RTC.
wdenkc6097192002-11-03 00:24:07 +0000783
wdenkb9bbd242003-06-30 16:24:52 +0000784 Note that if the RTC uses I2C, then the I2C interface
785 must also be configured. See I2C Support, below.
786
Peter Tyser9902e422008-12-17 16:36:21 -0600787- GPIO Support:
788 CONFIG_PCA953X - use NXP's PCA953X series I2C GPIO
Peter Tyser9902e422008-12-17 16:36:21 -0600789
Chris Packham9b383202010-12-19 10:12:13 +0000790 The CONFIG_SYS_I2C_PCA953X_WIDTH option specifies a list of
791 chip-ngpio pairs that tell the PCA953X driver the number of
792 pins supported by a particular chip.
793
Peter Tyser9902e422008-12-17 16:36:21 -0600794 Note that if the GPIO device uses I2C, then the I2C interface
795 must also be configured. See I2C Support, below.
796
Simon Glass4dc47ca2014-06-11 23:29:41 -0600797- I/O tracing:
798 When CONFIG_IO_TRACE is selected, U-Boot intercepts all I/O
799 accesses and can checksum them or write a list of them out
800 to memory. See the 'iotrace' command for details. This is
801 useful for testing device drivers since it can confirm that
802 the driver behaves the same way before and after a code
803 change. Currently this is supported on sandbox and arm. To
804 add support for your architecture, add '#include <iotrace.h>'
805 to the bottom of arch/<arch>/include/asm/io.h and test.
806
807 Example output from the 'iotrace stats' command is below.
808 Note that if the trace buffer is exhausted, the checksum will
809 still continue to operate.
810
811 iotrace is enabled
812 Start: 10000000 (buffer start address)
813 Size: 00010000 (buffer size)
814 Offset: 00000120 (current buffer offset)
815 Output: 10000120 (start + offset)
816 Count: 00000018 (number of trace records)
817 CRC32: 9526fb66 (CRC32 of all trace records)
818
wdenkc6097192002-11-03 00:24:07 +0000819- Timestamp Support:
820
wdenk4a5c8a72003-03-06 00:02:04 +0000821 When CONFIG_TIMESTAMP is selected, the timestamp
822 (date and time) of an image is printed by image
823 commands like bootm or iminfo. This option is
Jon Loeligerc1da5c92007-06-11 19:03:39 -0500824 automatically enabled when you select CONFIG_CMD_DATE .
wdenkc6097192002-11-03 00:24:07 +0000825
Karl O. Pinc8b1f90a2012-08-16 06:20:15 +0000826- Partition Labels (disklabels) Supported:
827 Zero or more of the following:
828 CONFIG_MAC_PARTITION Apple's MacOS partition table.
Karl O. Pinc8b1f90a2012-08-16 06:20:15 +0000829 CONFIG_ISO_PARTITION ISO partition table, used on CDROM etc.
830 CONFIG_EFI_PARTITION GPT partition table, common when EFI is the
831 bootloader. Note 2TB partition limit; see
832 disk/part_efi.c
Simon Glass8706b812016-05-01 11:36:02 -0600833 CONFIG_SCSI) you must configure support for at
Karl O. Pinc8b1f90a2012-08-16 06:20:15 +0000834 least one non-MTD partition type as well.
wdenkc6097192002-11-03 00:24:07 +0000835
836- IDE Reset method:
wdenk369d43d2004-03-14 14:09:05 +0000837 CONFIG_IDE_RESET_ROUTINE - this is defined in several
838 board configurations files but used nowhere!
wdenkc6097192002-11-03 00:24:07 +0000839
wdenk369d43d2004-03-14 14:09:05 +0000840 CONFIG_IDE_RESET - is this is defined, IDE Reset will
841 be performed by calling the function
842 ide_set_reset(int reset)
843 which has to be defined in a board specific file
wdenkc6097192002-11-03 00:24:07 +0000844
845- ATAPI Support:
846 CONFIG_ATAPI
847
848 Set this to enable ATAPI support.
849
wdenkf602aa02004-03-13 23:29:43 +0000850- LBA48 Support
851 CONFIG_LBA48
852
853 Set this to enable support for disks larger than 137GB
Heiko Schocher0f602e12009-12-03 11:21:21 +0100854 Also look at CONFIG_SYS_64BIT_LBA.
wdenkf602aa02004-03-13 23:29:43 +0000855 Whithout these , LBA48 support uses 32bit variables and will 'only'
856 support disks up to 2.1TB.
857
Jean-Christophe PLAGNIOL-VILLARD03836942008-10-16 15:01:15 +0200858 CONFIG_SYS_64BIT_LBA:
wdenkf602aa02004-03-13 23:29:43 +0000859 When enabled, makes the IDE subsystem use 64bit sector addresses.
860 Default is 32bit.
861
wdenkc6097192002-11-03 00:24:07 +0000862- SCSI Support:
Jean-Christophe PLAGNIOL-VILLARD03836942008-10-16 15:01:15 +0200863 CONFIG_SYS_SCSI_MAX_LUN [8], CONFIG_SYS_SCSI_MAX_SCSI_ID [7] and
864 CONFIG_SYS_SCSI_MAX_DEVICE [CONFIG_SYS_SCSI_MAX_SCSI_ID *
865 CONFIG_SYS_SCSI_MAX_LUN] can be adjusted to define the
wdenkc6097192002-11-03 00:24:07 +0000866 maximum numbers of LUNs, SCSI ID's and target
867 devices.
wdenkc6097192002-11-03 00:24:07 +0000868
Wolfgang Denkec7fbf52013-10-04 17:43:24 +0200869 The environment variable 'scsidevs' is set to the number of
870 SCSI devices found during the last scan.
Stefan Reinauere50a10e2012-10-29 05:23:48 +0000871
wdenkc6097192002-11-03 00:24:07 +0000872- NETWORK Support (PCI):
wdenk4e112c12003-06-03 23:54:09 +0000873 CONFIG_E1000
Kyle Moffett64b94dd2011-10-18 11:05:29 +0000874 Support for Intel 8254x/8257x gigabit chips.
875
876 CONFIG_E1000_SPI
877 Utility code for direct access to the SPI bus on Intel 8257x.
878 This does not do anything useful unless you set at least one
879 of CONFIG_CMD_E1000 or CONFIG_E1000_SPI_GENERIC.
880
881 CONFIG_E1000_SPI_GENERIC
882 Allow generic access to the SPI bus on the Intel 8257x, for
883 example with the "sspi" command.
884
wdenkc6097192002-11-03 00:24:07 +0000885 CONFIG_EEPRO100
886 Support for Intel 82557/82559/82559ER chips.
Marcel Ziswilerabd8dcb2008-07-09 08:17:15 +0200887 Optional CONFIG_EEPRO100_SROM_WRITE enables EEPROM
wdenkc6097192002-11-03 00:24:07 +0000888 write routine for first time initialisation.
889
890 CONFIG_TULIP
891 Support for Digital 2114x chips.
892 Optional CONFIG_TULIP_SELECT_MEDIA for board specific
893 modem chip initialisation (KS8761/QS6611).
894
895 CONFIG_NATSEMI
896 Support for National dp83815 chips.
897
898 CONFIG_NS8382X
899 Support for National dp8382[01] gigabit chips.
900
wdenkaa603362003-05-12 21:50:16 +0000901- NETWORK Support (other):
902
Jens Scharsigdab7cb82010-01-23 12:03:45 +0100903 CONFIG_DRIVER_AT91EMAC
904 Support for AT91RM9200 EMAC.
905
906 CONFIG_RMII
907 Define this to use reduced MII inteface
908
909 CONFIG_DRIVER_AT91EMAC_QUIET
910 If this defined, the driver is quiet.
911 The driver doen't show link status messages.
912
Rob Herringc9830dc2011-12-15 11:15:49 +0000913 CONFIG_CALXEDA_XGMAC
914 Support for the Calxeda XGMAC device
915
Ashok93fb8722012-10-15 06:20:47 +0000916 CONFIG_LAN91C96
wdenkaa603362003-05-12 21:50:16 +0000917 Support for SMSC's LAN91C96 chips.
918
wdenkaa603362003-05-12 21:50:16 +0000919 CONFIG_LAN91C96_USE_32_BIT
920 Define this to enable 32 bit addressing
921
Ashok93fb8722012-10-15 06:20:47 +0000922 CONFIG_SMC91111
wdenk3c711762004-06-09 13:37:52 +0000923 Support for SMSC's LAN91C111 chip
924
925 CONFIG_SMC91111_BASE
926 Define this to hold the physical address
927 of the device (I/O space)
928
929 CONFIG_SMC_USE_32_BIT
930 Define this if data bus is 32 bits
931
932 CONFIG_SMC_USE_IOFUNCS
933 Define this to use i/o functions instead of macros
934 (some hardware wont work with macros)
935
Heiko Schocher7d037f72011-11-15 10:00:04 -0500936 CONFIG_SYS_DAVINCI_EMAC_PHY_COUNT
937 Define this if you have more then 3 PHYs.
938
Macpaul Lin199c6252010-12-21 16:59:46 +0800939 CONFIG_FTGMAC100
940 Support for Faraday's FTGMAC100 Gigabit SoC Ethernet
941
942 CONFIG_FTGMAC100_EGIGA
943 Define this to use GE link update with gigabit PHY.
944 Define this if FTGMAC100 is connected to gigabit PHY.
945 If your system has 10/100 PHY only, it might not occur
946 wrong behavior. Because PHY usually return timeout or
947 useless data when polling gigabit status and gigabit
948 control registers. This behavior won't affect the
949 correctnessof 10/100 link speed update.
950
Yoshihiro Shimodaed4cea02011-01-27 10:06:03 +0900951 CONFIG_SH_ETHER
952 Support for Renesas on-chip Ethernet controller
953
954 CONFIG_SH_ETHER_USE_PORT
955 Define the number of ports to be used
956
957 CONFIG_SH_ETHER_PHY_ADDR
958 Define the ETH PHY's address
959
Yoshihiro Shimoda281aa052011-01-27 10:06:08 +0900960 CONFIG_SH_ETHER_CACHE_WRITEBACK
961 If this option is set, the driver enables cache flush.
962
Vadim Bendeburydac69642011-10-17 08:36:14 +0000963- TPM Support:
Che-liang Chiouacea5702013-04-12 11:04:34 +0000964 CONFIG_TPM
965 Support TPM devices.
966
Christophe Ricard8759ff82015-10-06 22:54:41 +0200967 CONFIG_TPM_TIS_INFINEON
968 Support for Infineon i2c bus TPM devices. Only one device
Tom Wai-Hong Tame49fed52013-04-12 11:04:37 +0000969 per system is supported at this time.
970
Tom Wai-Hong Tame49fed52013-04-12 11:04:37 +0000971 CONFIG_TPM_TIS_I2C_BURST_LIMITATION
972 Define the burst count bytes upper limit
973
Christophe Ricard88249232016-01-21 23:27:13 +0100974 CONFIG_TPM_ST33ZP24
975 Support for STMicroelectronics TPM devices. Requires DM_TPM support.
976
977 CONFIG_TPM_ST33ZP24_I2C
978 Support for STMicroelectronics ST33ZP24 I2C devices.
979 Requires TPM_ST33ZP24 and I2C.
980
Christophe Ricard5ffadc32016-01-21 23:27:14 +0100981 CONFIG_TPM_ST33ZP24_SPI
982 Support for STMicroelectronics ST33ZP24 SPI devices.
983 Requires TPM_ST33ZP24 and SPI.
984
Dirk Eibach20489092013-06-26 15:55:15 +0200985 CONFIG_TPM_ATMEL_TWI
986 Support for Atmel TWI TPM device. Requires I2C support.
987
Che-liang Chiouacea5702013-04-12 11:04:34 +0000988 CONFIG_TPM_TIS_LPC
Vadim Bendeburydac69642011-10-17 08:36:14 +0000989 Support for generic parallel port TPM devices. Only one device
990 per system is supported at this time.
991
992 CONFIG_TPM_TIS_BASE_ADDRESS
993 Base address where the generic TPM device is mapped
994 to. Contemporary x86 systems usually map it at
995 0xfed40000.
996
Reinhard Pfau4fece432013-06-26 15:55:13 +0200997 CONFIG_TPM
998 Define this to enable the TPM support library which provides
999 functional interfaces to some TPM commands.
1000 Requires support for a TPM device.
1001
1002 CONFIG_TPM_AUTH_SESSIONS
1003 Define this to enable authorized functions in the TPM library.
1004 Requires CONFIG_TPM and CONFIG_SHA1.
1005
wdenkc6097192002-11-03 00:24:07 +00001006- USB Support:
1007 At the moment only the UHCI host controller is
Heiko Schocher6f90e582017-06-14 05:49:40 +02001008 supported (PIP405, MIP405); define
wdenkc6097192002-11-03 00:24:07 +00001009 CONFIG_USB_UHCI to enable it.
1010 define CONFIG_USB_KEYBOARD to enable the USB Keyboard
wdenkfb30b4c2004-10-09 22:44:59 +00001011 and define CONFIG_USB_STORAGE to enable the USB
wdenkc6097192002-11-03 00:24:07 +00001012 storage devices.
1013 Note:
1014 Supported are USB Keyboards and USB Floppy drives
1015 (TEAC FD-05PUB).
wdenk369d43d2004-03-14 14:09:05 +00001016
Simon Glass5978cdb2012-02-27 10:52:47 +00001017 CONFIG_USB_EHCI_TXFIFO_THRESH enables setting of the
1018 txfilltuning field in the EHCI controller on reset.
1019
Oleksandr Tymoshenko7a881752014-02-01 21:51:25 -07001020 CONFIG_USB_DWC2_REG_ADDR the physical CPU address of the DWC2
1021 HW module registers.
1022
Wolfgang Denk3f0137b2006-06-14 17:45:53 +02001023- USB Device:
1024 Define the below if you wish to use the USB console.
1025 Once firmware is rebuilt from a serial console issue the
1026 command "setenv stdin usbtty; setenv stdout usbtty" and
Marcel Ziswilerabd8dcb2008-07-09 08:17:15 +02001027 attach your USB cable. The Unix command "dmesg" should print
Wolfgang Denk3f0137b2006-06-14 17:45:53 +02001028 it has found a new device. The environment variable usbtty
1029 can be set to gserial or cdc_acm to enable your device to
Wolfgang Denke2601822006-06-14 18:14:56 +02001030 appear to a USB host as a Linux gserial device or a
Wolfgang Denk3f0137b2006-06-14 17:45:53 +02001031 Common Device Class Abstract Control Model serial device.
1032 If you select usbtty = gserial you should be able to enumerate
1033 a Linux host by
1034 # modprobe usbserial vendor=0xVendorID product=0xProductID
1035 else if using cdc_acm, simply setting the environment
1036 variable usbtty to be cdc_acm should suffice. The following
1037 might be defined in YourBoardName.h
Wolfgang Denke2601822006-06-14 18:14:56 +02001038
Wolfgang Denk3f0137b2006-06-14 17:45:53 +02001039 CONFIG_USB_DEVICE
1040 Define this to build a UDC device
1041
1042 CONFIG_USB_TTY
1043 Define this to have a tty type of device available to
1044 talk to the UDC device
Wolfgang Denke2601822006-06-14 18:14:56 +02001045
Vipin KUMARbdb17702012-03-26 15:38:06 +05301046 CONFIG_USBD_HS
1047 Define this to enable the high speed support for usb
1048 device and usbtty. If this feature is enabled, a routine
1049 int is_usbd_high_speed(void)
1050 also needs to be defined by the driver to dynamically poll
1051 whether the enumeration has succeded at high speed or full
1052 speed.
1053
Jean-Christophe PLAGNIOL-VILLARD03836942008-10-16 15:01:15 +02001054 CONFIG_SYS_CONSOLE_IS_IN_ENV
Wolfgang Denk3f0137b2006-06-14 17:45:53 +02001055 Define this if you want stdin, stdout &/or stderr to
1056 be set to usbtty.
1057
Wolfgang Denke2601822006-06-14 18:14:56 +02001058 If you have a USB-IF assigned VendorID then you may wish to
Wolfgang Denk3f0137b2006-06-14 17:45:53 +02001059 define your own vendor specific values either in BoardName.h
Wolfgang Denke2601822006-06-14 18:14:56 +02001060 or directly in usbd_vendor_info.h. If you don't define
Wolfgang Denk3f0137b2006-06-14 17:45:53 +02001061 CONFIG_USBD_MANUFACTURER, CONFIG_USBD_PRODUCT_NAME,
1062 CONFIG_USBD_VENDORID and CONFIG_USBD_PRODUCTID, then U-Boot
1063 should pretend to be a Linux device to it's target host.
1064
1065 CONFIG_USBD_MANUFACTURER
1066 Define this string as the name of your company for
1067 - CONFIG_USBD_MANUFACTURER "my company"
Wolfgang Denke2601822006-06-14 18:14:56 +02001068
Wolfgang Denk3f0137b2006-06-14 17:45:53 +02001069 CONFIG_USBD_PRODUCT_NAME
1070 Define this string as the name of your product
1071 - CONFIG_USBD_PRODUCT_NAME "acme usb device"
wdenkc6097192002-11-03 00:24:07 +00001072
Wolfgang Denk3f0137b2006-06-14 17:45:53 +02001073 CONFIG_USBD_VENDORID
1074 Define this as your assigned Vendor ID from the USB
1075 Implementors Forum. This *must* be a genuine Vendor ID
1076 to avoid polluting the USB namespace.
1077 - CONFIG_USBD_VENDORID 0xFFFF
Wolfgang Denke2601822006-06-14 18:14:56 +02001078
Wolfgang Denk3f0137b2006-06-14 17:45:53 +02001079 CONFIG_USBD_PRODUCTID
1080 Define this as the unique Product ID
1081 for your device
1082 - CONFIG_USBD_PRODUCTID 0xFFFF
Wolfgang Denke2601822006-06-14 18:14:56 +02001083
Igor Grinbergac5f6ee2011-12-12 12:08:35 +02001084- ULPI Layer Support:
1085 The ULPI (UTMI Low Pin (count) Interface) PHYs are supported via
1086 the generic ULPI layer. The generic layer accesses the ULPI PHY
1087 via the platform viewport, so you need both the genric layer and
1088 the viewport enabled. Currently only Chipidea/ARC based
1089 viewport is supported.
1090 To enable the ULPI layer support, define CONFIG_USB_ULPI and
1091 CONFIG_USB_ULPI_VIEWPORT in your board configuration file.
Lucas Stachf31e4112012-10-01 00:44:35 +02001092 If your ULPI phy needs a different reference clock than the
1093 standard 24 MHz then you have to define CONFIG_ULPI_REF_CLK to
1094 the appropriate value in Hz.
wdenkc6097192002-11-03 00:24:07 +00001095
wdenk7a428cc2003-06-15 22:40:42 +00001096- MMC Support:
wdenk57b2d802003-06-27 21:31:46 +00001097 The MMC controller on the Intel PXA is supported. To
1098 enable this define CONFIG_MMC. The MMC can be
1099 accessed from the boot prompt by mapping the device
wdenk7a428cc2003-06-15 22:40:42 +00001100 to physical memory similar to flash. Command line is
Jon Loeligerc1da5c92007-06-11 19:03:39 -05001101 enabled with CONFIG_CMD_MMC. The MMC driver also works with
1102 the FAT fs. This is enabled with CONFIG_CMD_FAT.
wdenk7a428cc2003-06-15 22:40:42 +00001103
Yoshihiro Shimodadb7717b2011-07-04 22:21:22 +00001104 CONFIG_SH_MMCIF
1105 Support for Renesas on-chip MMCIF controller
1106
1107 CONFIG_SH_MMCIF_ADDR
1108 Define the base address of MMCIF registers
1109
1110 CONFIG_SH_MMCIF_CLK
1111 Define the clock frequency for MMCIF
1112
Tom Rini58a8d322013-03-14 05:32:47 +00001113- USB Device Firmware Update (DFU) class support:
Marek Vasut7f8d4362018-02-16 16:41:18 +01001114 CONFIG_DFU_OVER_USB
Tom Rini58a8d322013-03-14 05:32:47 +00001115 This enables the USB portion of the DFU USB class
1116
Pantelis Antonioucf14d0d2013-03-14 05:32:52 +00001117 CONFIG_DFU_NAND
1118 This enables support for exposing NAND devices via DFU.
1119
Afzal Mohammede3c687a2013-09-18 01:15:24 +05301120 CONFIG_DFU_RAM
1121 This enables support for exposing RAM via DFU.
1122 Note: DFU spec refer to non-volatile memory usage, but
1123 allow usages beyond the scope of spec - here RAM usage,
1124 one that would help mostly the developer.
1125
Heiko Schochera2f831e2013-06-12 06:05:51 +02001126 CONFIG_SYS_DFU_DATA_BUF_SIZE
1127 Dfu transfer uses a buffer before writing data to the
1128 raw storage device. Make the size (in bytes) of this buffer
1129 configurable. The size of this buffer is also configurable
1130 through the "dfu_bufsiz" environment variable.
1131
Pantelis Antonioua6e788d2013-03-14 05:32:48 +00001132 CONFIG_SYS_DFU_MAX_FILE_SIZE
1133 When updating files rather than the raw storage device,
1134 we use a static buffer to copy the file into and then write
1135 the buffer once we've been given the whole file. Define
1136 this to the maximum filesize (in bytes) for the buffer.
1137 Default is 4 MiB if undefined.
1138
Heiko Schochere1ba1512014-03-18 08:09:56 +01001139 DFU_DEFAULT_POLL_TIMEOUT
1140 Poll timeout [ms], is the timeout a device can send to the
1141 host. The host must wait for this timeout before sending
1142 a subsequent DFU_GET_STATUS request to the device.
1143
1144 DFU_MANIFEST_POLL_TIMEOUT
1145 Poll timeout [ms], which the device sends to the host when
1146 entering dfuMANIFEST state. Host waits this timeout, before
1147 sending again an USB request to the device.
1148
wdenkda04a8b2004-08-02 23:22:59 +00001149- Journaling Flash filesystem support:
Simon Glassfa8527b2016-10-02 18:00:59 -06001150 CONFIG_JFFS2_NAND
wdenkda04a8b2004-08-02 23:22:59 +00001151 Define these for a default partition on a NAND device
1152
Jean-Christophe PLAGNIOL-VILLARD03836942008-10-16 15:01:15 +02001153 CONFIG_SYS_JFFS2_FIRST_SECTOR,
1154 CONFIG_SYS_JFFS2_FIRST_BANK, CONFIG_SYS_JFFS2_NUM_BANKS
wdenkda04a8b2004-08-02 23:22:59 +00001155 Define these for a default partition on a NOR device
1156
wdenkc6097192002-11-03 00:24:07 +00001157- Keyboard Support:
Simon Glasseaba37e2015-11-11 10:05:47 -07001158 See Kconfig help for available keyboard drivers.
1159
1160 CONFIG_KEYBOARD
1161
1162 Define this to enable a custom keyboard support.
1163 This simply calls drv_keyboard_init() which must be
1164 defined in your board-specific files. This option is deprecated
1165 and is only used by novena. For new boards, use driver model
1166 instead.
wdenkc6097192002-11-03 00:24:07 +00001167
1168- Video support:
Timur Tabi020edd22011-02-15 17:09:19 -06001169 CONFIG_FSL_DIU_FB
Wolfgang Denk825223d2011-09-11 21:24:09 +02001170 Enable the Freescale DIU video driver. Reference boards for
Timur Tabi020edd22011-02-15 17:09:19 -06001171 SOCs that have a DIU should define this macro to enable DIU
1172 support, and should also define these other macros:
1173
1174 CONFIG_SYS_DIU_ADDR
1175 CONFIG_VIDEO
Timur Tabi020edd22011-02-15 17:09:19 -06001176 CONFIG_CFB_CONSOLE
1177 CONFIG_VIDEO_SW_CURSOR
1178 CONFIG_VGA_AS_SINGLE_DEVICE
1179 CONFIG_VIDEO_LOGO
1180 CONFIG_VIDEO_BMP_LOGO
1181
Timur Tabi32f709e2011-04-11 14:18:22 -05001182 The DIU driver will look for the 'video-mode' environment
1183 variable, and if defined, enable the DIU as a console during
Fabio Estevamd3ad5e52016-04-02 11:53:18 -03001184 boot. See the documentation file doc/README.video for a
Timur Tabi32f709e2011-04-11 14:18:22 -05001185 description of this variable.
Timur Tabi020edd22011-02-15 17:09:19 -06001186
wdenkc6097192002-11-03 00:24:07 +00001187- LCD Support: CONFIG_LCD
1188
1189 Define this to enable LCD support (for output to LCD
1190 display); also select one of the supported displays
1191 by defining one of these:
1192
Stelian Popf6f86652008-05-09 21:57:18 +02001193 CONFIG_ATMEL_LCD:
1194
1195 HITACHI TX09D70VM1CCA, 3.5", 240x320.
1196
wdenkc0d54ae2003-11-25 16:55:19 +00001197 CONFIG_NEC_NL6448AC33:
wdenkc6097192002-11-03 00:24:07 +00001198
wdenkc0d54ae2003-11-25 16:55:19 +00001199 NEC NL6448AC33-18. Active, color, single scan.
wdenkc6097192002-11-03 00:24:07 +00001200
wdenkc0d54ae2003-11-25 16:55:19 +00001201 CONFIG_NEC_NL6448BC20
1202
1203 NEC NL6448BC20-08. 6.5", 640x480.
1204 Active, color, single scan.
1205
1206 CONFIG_NEC_NL6448BC33_54
wdenkc6097192002-11-03 00:24:07 +00001207
wdenkc0d54ae2003-11-25 16:55:19 +00001208 NEC NL6448BC33-54. 10.4", 640x480.
wdenkc6097192002-11-03 00:24:07 +00001209 Active, color, single scan.
1210
1211 CONFIG_SHARP_16x9
1212
1213 Sharp 320x240. Active, color, single scan.
1214 It isn't 16x9, and I am not sure what it is.
1215
1216 CONFIG_SHARP_LQ64D341
1217
1218 Sharp LQ64D341 display, 640x480.
1219 Active, color, single scan.
1220
1221 CONFIG_HLD1045
1222
1223 HLD1045 display, 640x480.
1224 Active, color, single scan.
1225
1226 CONFIG_OPTREX_BW
1227
1228 Optrex CBL50840-2 NF-FW 99 22 M5
1229 or
1230 Hitachi LMG6912RPFC-00T
1231 or
1232 Hitachi SP14Q002
1233
1234 320x240. Black & white.
1235
Simon Glass599a4df2012-10-17 13:24:54 +00001236 CONFIG_LCD_ALIGNMENT
1237
Jeremiah Mahler03f930c2015-01-04 18:56:50 -08001238 Normally the LCD is page-aligned (typically 4KB). If this is
Simon Glass599a4df2012-10-17 13:24:54 +00001239 defined then the LCD will be aligned to this value instead.
1240 For ARM it is sometimes useful to use MMU_SECTION_SIZE
1241 here, since it is cheaper to change data cache settings on
1242 a per-section basis.
1243
1244
Hannes Petermaiera3c8e862015-03-27 08:01:38 +01001245 CONFIG_LCD_ROTATION
1246
1247 Sometimes, for example if the display is mounted in portrait
1248 mode or even if it's mounted landscape but rotated by 180degree,
1249 we need to rotate our content of the display relative to the
1250 framebuffer, so that user can read the messages which are
1251 printed out.
1252 Once CONFIG_LCD_ROTATION is defined, the lcd_console will be
1253 initialized with a given rotation from "vl_rot" out of
1254 "vidinfo_t" which is provided by the board specific code.
1255 The value for vl_rot is coded as following (matching to
1256 fbcon=rotate:<n> linux-kernel commandline):
1257 0 = no rotation respectively 0 degree
1258 1 = 90 degree rotation
1259 2 = 180 degree rotation
1260 3 = 270 degree rotation
1261
1262 If CONFIG_LCD_ROTATION is not defined, the console will be
1263 initialized with 0degree rotation.
1264
Tom Wai-Hong Tam79926a42012-09-28 15:11:16 +00001265 CONFIG_LCD_BMP_RLE8
1266
1267 Support drawing of RLE8-compressed bitmaps on the LCD.
1268
Tom Wai-Hong Tam6664f202012-12-05 14:46:40 +00001269 CONFIG_I2C_EDID
1270
1271 Enables an 'i2c edid' command which can read EDID
1272 information over I2C from an attached LCD display.
1273
wdenkeb20ad32003-09-05 23:19:14 +00001274- Splash Screen Support: CONFIG_SPLASH_SCREEN
wdenk92bbe3f2003-04-20 14:04:18 +00001275
wdenk57b2d802003-06-27 21:31:46 +00001276 If this option is set, the environment is checked for
1277 a variable "splashimage". If found, the usual display
1278 of logo, copyright and system information on the LCD
wdenk01686632004-06-30 22:59:18 +00001279 is suppressed and the BMP image at the address
wdenk57b2d802003-06-27 21:31:46 +00001280 specified in "splashimage" is loaded instead. The
1281 console is redirected to the "nulldev", too. This
1282 allows for a "silent" boot where a splash screen is
1283 loaded very quickly after power-on.
wdenk92bbe3f2003-04-20 14:04:18 +00001284
Nikita Kiryanov2f3e2ca2013-02-24 21:28:43 +00001285 CONFIG_SPLASHIMAGE_GUARD
1286
1287 If this option is set, then U-Boot will prevent the environment
1288 variable "splashimage" from being set to a problematic address
Fabio Estevama58b4912016-03-23 12:46:12 -03001289 (see doc/README.displaying-bmps).
Nikita Kiryanov2f3e2ca2013-02-24 21:28:43 +00001290 This option is useful for targets where, due to alignment
1291 restrictions, an improperly aligned BMP image will cause a data
1292 abort. If you think you will not have problems with unaligned
1293 accesses (for example because your toolchain prevents them)
1294 there is no need to set this option.
1295
Matthias Weisser53884182009-07-09 16:07:30 +02001296 CONFIG_SPLASH_SCREEN_ALIGN
1297
1298 If this option is set the splash image can be freely positioned
1299 on the screen. Environment variable "splashpos" specifies the
1300 position as "x,y". If a positive number is given it is used as
1301 number of pixel from left/top. If a negative number is given it
1302 is used as number of pixel from right/bottom. You can also
1303 specify 'm' for centering the image.
1304
1305 Example:
1306 setenv splashpos m,m
1307 => image at center of screen
1308
1309 setenv splashpos 30,20
1310 => image at x = 30 and y = 20
1311
1312 setenv splashpos -10,m
1313 => vertically centered image
1314 at x = dspWidth - bmpWidth - 9
1315
Stefan Roesed9d97742005-09-22 09:04:17 +02001316- Gzip compressed BMP image support: CONFIG_VIDEO_BMP_GZIP
1317
1318 If this option is set, additionally to standard BMP
1319 images, gzipped BMP images can be displayed via the
1320 splashscreen support or the bmp command.
1321
Anatolij Gustschin6b4e4fc2010-03-15 14:50:25 +01001322- Run length encoded BMP image (RLE8) support: CONFIG_VIDEO_BMP_RLE8
1323
1324 If this option is set, 8-bit RLE compressed BMP images
1325 can be displayed via the splashscreen support or the
1326 bmp command.
1327
wdenk710e3502003-08-29 20:57:53 +00001328- Compression support:
Kees Cook5b06e642013-08-16 07:59:12 -07001329 CONFIG_GZIP
1330
1331 Enabled by default to support gzip compressed images.
1332
wdenk710e3502003-08-29 20:57:53 +00001333 CONFIG_BZIP2
1334
1335 If this option is set, support for bzip2 compressed
1336 images is included. If not, only uncompressed and gzip
1337 compressed images are supported.
1338
wdenk9c53f402003-10-15 23:53:47 +00001339 NOTE: the bzip2 algorithm requires a lot of RAM, so
Jean-Christophe PLAGNIOL-VILLARD03836942008-10-16 15:01:15 +02001340 the malloc area (as defined by CONFIG_SYS_MALLOC_LEN) should
wdenk9c53f402003-10-15 23:53:47 +00001341 be at least 4MB.
wdenk92bbe3f2003-04-20 14:04:18 +00001342
wdenk0e2bd9c2004-06-06 21:51:03 +00001343- MII/PHY support:
wdenk0e2bd9c2004-06-06 21:51:03 +00001344 CONFIG_PHY_CLOCK_FREQ (ppc4xx)
1345
1346 The clock frequency of the MII bus
1347
wdenk0e2bd9c2004-06-06 21:51:03 +00001348 CONFIG_PHY_RESET_DELAY
1349
1350 Some PHY like Intel LXT971A need extra delay after
1351 reset before any MII register access is possible.
1352 For such PHY, set this option to the usec delay
1353 required. (minimum 300usec for LXT971A)
1354
1355 CONFIG_PHY_CMD_DELAY (ppc4xx)
1356
1357 Some PHY like Intel LXT971A need extra delay after
1358 command issued before MII status register can be read
1359
wdenkc6097192002-11-03 00:24:07 +00001360- IP address:
1361 CONFIG_IPADDR
1362
1363 Define a default value for the IP address to use for
Marcel Ziswilerabd8dcb2008-07-09 08:17:15 +02001364 the default Ethernet interface, in case this is not
wdenkc6097192002-11-03 00:24:07 +00001365 determined through e.g. bootp.
Wolfgang Denk26da2992011-10-26 10:21:22 +00001366 (Environment variable "ipaddr")
wdenkc6097192002-11-03 00:24:07 +00001367
1368- Server IP address:
1369 CONFIG_SERVERIP
1370
Marcel Ziswilerabd8dcb2008-07-09 08:17:15 +02001371 Defines a default value for the IP address of a TFTP
wdenkc6097192002-11-03 00:24:07 +00001372 server to contact when using the "tftboot" command.
Wolfgang Denk26da2992011-10-26 10:21:22 +00001373 (Environment variable "serverip")
wdenkc6097192002-11-03 00:24:07 +00001374
Robin Getz470a6d42009-07-21 12:15:28 -04001375 CONFIG_KEEP_SERVERADDR
1376
1377 Keeps the server's MAC address, in the env 'serveraddr'
1378 for passing to bootargs (like Linux's netconsole option)
1379
Wolfgang Denk26da2992011-10-26 10:21:22 +00001380- Gateway IP address:
1381 CONFIG_GATEWAYIP
1382
1383 Defines a default value for the IP address of the
1384 default router where packets to other networks are
1385 sent to.
1386 (Environment variable "gatewayip")
1387
1388- Subnet mask:
1389 CONFIG_NETMASK
1390
1391 Defines a default value for the subnet mask (or
1392 routing prefix) which is used to determine if an IP
1393 address belongs to the local subnet or needs to be
1394 forwarded through a router.
1395 (Environment variable "netmask")
1396
wdenkc6097192002-11-03 00:24:07 +00001397- BOOTP Recovery Mode:
1398 CONFIG_BOOTP_RANDOM_DELAY
1399
1400 If you have many targets in a network that try to
1401 boot using BOOTP, you may want to avoid that all
1402 systems send out BOOTP requests at precisely the same
1403 moment (which would happen for instance at recovery
1404 from a power failure, when all systems will try to
1405 boot, thus flooding the BOOTP server. Defining
1406 CONFIG_BOOTP_RANDOM_DELAY causes a random delay to be
1407 inserted before sending out BOOTP requests. The
Wolfgang Denkb65aaf92007-08-06 23:21:05 +02001408 following delays are inserted then:
wdenkc6097192002-11-03 00:24:07 +00001409
1410 1st BOOTP request: delay 0 ... 1 sec
1411 2nd BOOTP request: delay 0 ... 2 sec
1412 3rd BOOTP request: delay 0 ... 4 sec
1413 4th and following
1414 BOOTP requests: delay 0 ... 8 sec
1415
Thierry Reding8977cda2014-08-19 10:21:24 +02001416 CONFIG_BOOTP_ID_CACHE_SIZE
1417
1418 BOOTP packets are uniquely identified using a 32-bit ID. The
1419 server will copy the ID from client requests to responses and
1420 U-Boot will use this to determine if it is the destination of
1421 an incoming response. Some servers will check that addresses
1422 aren't in use before handing them out (usually using an ARP
1423 ping) and therefore take up to a few hundred milliseconds to
1424 respond. Network congestion may also influence the time it
1425 takes for a response to make it back to the client. If that
1426 time is too long, U-Boot will retransmit requests. In order
1427 to allow earlier responses to still be accepted after these
1428 retransmissions, U-Boot's BOOTP client keeps a small cache of
1429 IDs. The CONFIG_BOOTP_ID_CACHE_SIZE controls the size of this
1430 cache. The default is to keep IDs for up to four outstanding
1431 requests. Increasing this will allow U-Boot to accept offers
1432 from a BOOTP client in networks with unusually high latency.
1433
stroesee0aadfb2003-08-28 14:17:32 +00001434- DHCP Advanced Options:
Jon Loeliger5336a762007-07-09 22:08:34 -05001435 You can fine tune the DHCP functionality by defining
1436 CONFIG_BOOTP_* symbols:
stroesee0aadfb2003-08-28 14:17:32 +00001437
Jon Loeliger5336a762007-07-09 22:08:34 -05001438 CONFIG_BOOTP_NISDOMAIN
Jon Loeliger5336a762007-07-09 22:08:34 -05001439 CONFIG_BOOTP_BOOTFILESIZE
Jon Loeliger5336a762007-07-09 22:08:34 -05001440 CONFIG_BOOTP_SEND_HOSTNAME
1441 CONFIG_BOOTP_NTPSERVER
1442 CONFIG_BOOTP_TIMEOFFSET
1443 CONFIG_BOOTP_VENDOREX
Joe Hershberger8ca7fa02012-05-23 07:59:19 +00001444 CONFIG_BOOTP_MAY_FAIL
stroesee0aadfb2003-08-28 14:17:32 +00001445
Wilson Callan22bcd6e2007-07-28 10:56:13 -04001446 CONFIG_BOOTP_SERVERIP - TFTP server will be the serverip
1447 environment variable, not the BOOTP server.
stroesee0aadfb2003-08-28 14:17:32 +00001448
Joe Hershberger8ca7fa02012-05-23 07:59:19 +00001449 CONFIG_BOOTP_MAY_FAIL - If the DHCP server is not found
1450 after the configured retry count, the call will fail
1451 instead of starting over. This can be used to fail over
1452 to Link-local IP address configuration if the DHCP server
1453 is not available.
1454
stroesee0aadfb2003-08-28 14:17:32 +00001455 CONFIG_BOOTP_SEND_HOSTNAME - Some DHCP servers are capable
1456 to do a dynamic update of a DNS server. To do this, they
1457 need the hostname of the DHCP requester.
Wilson Callan22bcd6e2007-07-28 10:56:13 -04001458 If CONFIG_BOOTP_SEND_HOSTNAME is defined, the content
Jon Loeliger5336a762007-07-09 22:08:34 -05001459 of the "hostname" environment variable is passed as
1460 option 12 to the DHCP server.
stroesee0aadfb2003-08-28 14:17:32 +00001461
Aras Vaichas72aa3f32008-03-26 09:43:57 +11001462 CONFIG_BOOTP_DHCP_REQUEST_DELAY
1463
1464 A 32bit value in microseconds for a delay between
1465 receiving a "DHCP Offer" and sending the "DHCP Request".
1466 This fixes a problem with certain DHCP servers that don't
1467 respond 100% of the time to a "DHCP request". E.g. On an
1468 AT91RM9200 processor running at 180MHz, this delay needed
1469 to be *at least* 15,000 usec before a Windows Server 2003
1470 DHCP server would reply 100% of the time. I recommend at
1471 least 50,000 usec to be safe. The alternative is to hope
1472 that one of the retries will be successful but note that
1473 the DHCP timeout and retry process takes a longer than
1474 this delay.
1475
Joe Hershbergerb35a3a62012-05-23 08:00:12 +00001476 - Link-local IP address negotiation:
1477 Negotiate with other link-local clients on the local network
1478 for an address that doesn't require explicit configuration.
1479 This is especially useful if a DHCP server cannot be guaranteed
1480 to exist in all environments that the device must operate.
1481
1482 See doc/README.link-local for more information.
1483
Prabhakar Kushwaha2dec06f2017-11-23 16:51:32 +05301484 - MAC address from environment variables
1485
1486 FDT_SEQ_MACADDR_FROM_ENV
1487
1488 Fix-up device tree with MAC addresses fetched sequentially from
1489 environment variables. This config work on assumption that
1490 non-usable ethernet node of device-tree are either not present
1491 or their status has been marked as "disabled".
1492
wdenk145d2c12004-04-15 21:48:45 +00001493 - CDP Options:
wdenk05939202004-04-18 17:39:38 +00001494 CONFIG_CDP_DEVICE_ID
wdenk145d2c12004-04-15 21:48:45 +00001495
1496 The device id used in CDP trigger frames.
1497
1498 CONFIG_CDP_DEVICE_ID_PREFIX
1499
1500 A two character string which is prefixed to the MAC address
1501 of the device.
1502
1503 CONFIG_CDP_PORT_ID
1504
1505 A printf format string which contains the ascii name of
1506 the port. Normally is set to "eth%d" which sets
Marcel Ziswilerabd8dcb2008-07-09 08:17:15 +02001507 eth0 for the first Ethernet, eth1 for the second etc.
wdenk145d2c12004-04-15 21:48:45 +00001508
1509 CONFIG_CDP_CAPABILITIES
1510
1511 A 32bit integer which indicates the device capabilities;
1512 0x00000010 for a normal host which does not forwards.
1513
1514 CONFIG_CDP_VERSION
1515
1516 An ascii string containing the version of the software.
1517
1518 CONFIG_CDP_PLATFORM
1519
1520 An ascii string containing the name of the platform.
1521
1522 CONFIG_CDP_TRIGGER
1523
1524 A 32bit integer sent on the trigger.
1525
1526 CONFIG_CDP_POWER_CONSUMPTION
1527
1528 A 16bit integer containing the power consumption of the
1529 device in .1 of milliwatts.
1530
1531 CONFIG_CDP_APPLIANCE_VLAN_TYPE
1532
1533 A byte containing the id of the VLAN.
1534
Uri Mashiach3dc6f652017-01-19 10:51:05 +02001535- Status LED: CONFIG_LED_STATUS
wdenkc6097192002-11-03 00:24:07 +00001536
1537 Several configurations allow to display the current
1538 status using a LED. For instance, the LED will blink
1539 fast while running U-Boot code, stop blinking as
1540 soon as a reply to a BOOTP request was received, and
1541 start blinking slow once the Linux kernel is running
1542 (supported by a status LED driver in the Linux
Uri Mashiach3dc6f652017-01-19 10:51:05 +02001543 kernel). Defining CONFIG_LED_STATUS enables this
wdenkc6097192002-11-03 00:24:07 +00001544 feature in U-Boot.
1545
Igor Grinberg4997a9e2013-11-08 01:03:50 +02001546 Additional options:
1547
Uri Mashiach3dc6f652017-01-19 10:51:05 +02001548 CONFIG_LED_STATUS_GPIO
Igor Grinberg4997a9e2013-11-08 01:03:50 +02001549 The status LED can be connected to a GPIO pin.
1550 In such cases, the gpio_led driver can be used as a
Uri Mashiach3dc6f652017-01-19 10:51:05 +02001551 status LED backend implementation. Define CONFIG_LED_STATUS_GPIO
Igor Grinberg4997a9e2013-11-08 01:03:50 +02001552 to include the gpio_led driver in the U-Boot binary.
1553
Igor Grinberg203bd9f2013-11-08 01:03:52 +02001554 CONFIG_GPIO_LED_INVERTED_TABLE
1555 Some GPIO connected LEDs may have inverted polarity in which
1556 case the GPIO high value corresponds to LED off state and
1557 GPIO low value corresponds to LED on state.
1558 In such cases CONFIG_GPIO_LED_INVERTED_TABLE may be defined
1559 with a list of GPIO LEDs that have inverted polarity.
1560
Heiko Schochere0e55bc2012-01-16 21:12:24 +00001561- I2C Support: CONFIG_SYS_I2C
wdenkc6097192002-11-03 00:24:07 +00001562
Heiko Schochere0e55bc2012-01-16 21:12:24 +00001563 This enable the NEW i2c subsystem, and will allow you to use
1564 i2c commands at the u-boot command line (as long as you set
1565 CONFIG_CMD_I2C in CONFIG_COMMANDS) and communicate with i2c
1566 based realtime clock chips or other i2c devices. See
1567 common/cmd_i2c.c for a description of the command line
1568 interface.
1569
1570 ported i2c driver to the new framework:
Heiko Schocher479a4cf2013-01-29 08:53:15 +01001571 - drivers/i2c/soft_i2c.c:
1572 - activate first bus with CONFIG_SYS_I2C_SOFT define
1573 CONFIG_SYS_I2C_SOFT_SPEED and CONFIG_SYS_I2C_SOFT_SLAVE
1574 for defining speed and slave address
1575 - activate second bus with I2C_SOFT_DECLARATIONS2 define
1576 CONFIG_SYS_I2C_SOFT_SPEED_2 and CONFIG_SYS_I2C_SOFT_SLAVE_2
1577 for defining speed and slave address
1578 - activate third bus with I2C_SOFT_DECLARATIONS3 define
1579 CONFIG_SYS_I2C_SOFT_SPEED_3 and CONFIG_SYS_I2C_SOFT_SLAVE_3
1580 for defining speed and slave address
1581 - activate fourth bus with I2C_SOFT_DECLARATIONS4 define
1582 CONFIG_SYS_I2C_SOFT_SPEED_4 and CONFIG_SYS_I2C_SOFT_SLAVE_4
1583 for defining speed and slave address
Heiko Schochere0e55bc2012-01-16 21:12:24 +00001584
Heiko Schocherf2850742012-10-24 13:48:22 +02001585 - drivers/i2c/fsl_i2c.c:
1586 - activate i2c driver with CONFIG_SYS_I2C_FSL
1587 define CONFIG_SYS_FSL_I2C_OFFSET for setting the register
1588 offset CONFIG_SYS_FSL_I2C_SPEED for the i2c speed and
1589 CONFIG_SYS_FSL_I2C_SLAVE for the slave addr of the first
1590 bus.
Wolfgang Denkec7fbf52013-10-04 17:43:24 +02001591 - If your board supports a second fsl i2c bus, define
Heiko Schocherf2850742012-10-24 13:48:22 +02001592 CONFIG_SYS_FSL_I2C2_OFFSET for the register offset
1593 CONFIG_SYS_FSL_I2C2_SPEED for the speed and
1594 CONFIG_SYS_FSL_I2C2_SLAVE for the slave address of the
1595 second bus.
1596
Simon Glass026fefb2012-10-30 07:28:53 +00001597 - drivers/i2c/tegra_i2c.c:
Nobuhiro Iwamatsu045acfa2013-10-11 16:23:53 +09001598 - activate this driver with CONFIG_SYS_I2C_TEGRA
1599 - This driver adds 4 i2c buses with a fix speed from
1600 100000 and the slave addr 0!
Simon Glass026fefb2012-10-30 07:28:53 +00001601
Dirk Eibach42b204f2013-04-25 02:40:01 +00001602 - drivers/i2c/ppc4xx_i2c.c
1603 - activate this driver with CONFIG_SYS_I2C_PPC4XX
1604 - CONFIG_SYS_I2C_PPC4XX_CH0 activate hardware channel 0
1605 - CONFIG_SYS_I2C_PPC4XX_CH1 activate hardware channel 1
1606
trema49f40a2013-09-21 18:13:35 +02001607 - drivers/i2c/i2c_mxc.c
1608 - activate this driver with CONFIG_SYS_I2C_MXC
Albert ARIBAUD \\(3ADEV\\)eb943872015-09-21 22:43:38 +02001609 - enable bus 1 with CONFIG_SYS_I2C_MXC_I2C1
1610 - enable bus 2 with CONFIG_SYS_I2C_MXC_I2C2
1611 - enable bus 3 with CONFIG_SYS_I2C_MXC_I2C3
1612 - enable bus 4 with CONFIG_SYS_I2C_MXC_I2C4
trema49f40a2013-09-21 18:13:35 +02001613 - define speed for bus 1 with CONFIG_SYS_MXC_I2C1_SPEED
1614 - define slave for bus 1 with CONFIG_SYS_MXC_I2C1_SLAVE
1615 - define speed for bus 2 with CONFIG_SYS_MXC_I2C2_SPEED
1616 - define slave for bus 2 with CONFIG_SYS_MXC_I2C2_SLAVE
1617 - define speed for bus 3 with CONFIG_SYS_MXC_I2C3_SPEED
1618 - define slave for bus 3 with CONFIG_SYS_MXC_I2C3_SLAVE
Albert ARIBAUD \\(3ADEV\\)eb943872015-09-21 22:43:38 +02001619 - define speed for bus 4 with CONFIG_SYS_MXC_I2C4_SPEED
1620 - define slave for bus 4 with CONFIG_SYS_MXC_I2C4_SLAVE
Jeremiah Mahler03f930c2015-01-04 18:56:50 -08001621 If those defines are not set, default value is 100000
trema49f40a2013-09-21 18:13:35 +02001622 for speed, and 0 for slave.
1623
Nobuhiro Iwamatsue94ea2f2013-09-27 16:58:30 +09001624 - drivers/i2c/rcar_i2c.c:
1625 - activate this driver with CONFIG_SYS_I2C_RCAR
1626 - This driver adds 4 i2c buses
1627
1628 - CONFIG_SYS_RCAR_I2C0_BASE for setting the register channel 0
1629 - CONFIG_SYS_RCAR_I2C0_SPEED for for the speed channel 0
1630 - CONFIG_SYS_RCAR_I2C1_BASE for setting the register channel 1
1631 - CONFIG_SYS_RCAR_I2C1_SPEED for for the speed channel 1
1632 - CONFIG_SYS_RCAR_I2C2_BASE for setting the register channel 2
1633 - CONFIG_SYS_RCAR_I2C2_SPEED for for the speed channel 2
1634 - CONFIG_SYS_RCAR_I2C3_BASE for setting the register channel 3
1635 - CONFIG_SYS_RCAR_I2C3_SPEED for for the speed channel 3
1636 - CONFIF_SYS_RCAR_I2C_NUM_CONTROLLERS for number of i2c buses
1637
Nobuhiro Iwamatsu12240102013-10-29 13:33:51 +09001638 - drivers/i2c/sh_i2c.c:
1639 - activate this driver with CONFIG_SYS_I2C_SH
1640 - This driver adds from 2 to 5 i2c buses
1641
1642 - CONFIG_SYS_I2C_SH_BASE0 for setting the register channel 0
1643 - CONFIG_SYS_I2C_SH_SPEED0 for for the speed channel 0
1644 - CONFIG_SYS_I2C_SH_BASE1 for setting the register channel 1
1645 - CONFIG_SYS_I2C_SH_SPEED1 for for the speed channel 1
1646 - CONFIG_SYS_I2C_SH_BASE2 for setting the register channel 2
1647 - CONFIG_SYS_I2C_SH_SPEED2 for for the speed channel 2
1648 - CONFIG_SYS_I2C_SH_BASE3 for setting the register channel 3
1649 - CONFIG_SYS_I2C_SH_SPEED3 for for the speed channel 3
1650 - CONFIG_SYS_I2C_SH_BASE4 for setting the register channel 4
1651 - CONFIG_SYS_I2C_SH_SPEED4 for for the speed channel 4
Jeremiah Mahler03f930c2015-01-04 18:56:50 -08001652 - CONFIG_SYS_I2C_SH_NUM_CONTROLLERS for number of i2c buses
Nobuhiro Iwamatsu12240102013-10-29 13:33:51 +09001653
Heiko Schocherf53f2b82013-10-22 11:03:18 +02001654 - drivers/i2c/omap24xx_i2c.c
1655 - activate this driver with CONFIG_SYS_I2C_OMAP24XX
1656 - CONFIG_SYS_OMAP24_I2C_SPEED speed channel 0
1657 - CONFIG_SYS_OMAP24_I2C_SLAVE slave addr channel 0
1658 - CONFIG_SYS_OMAP24_I2C_SPEED1 speed channel 1
1659 - CONFIG_SYS_OMAP24_I2C_SLAVE1 slave addr channel 1
1660 - CONFIG_SYS_OMAP24_I2C_SPEED2 speed channel 2
1661 - CONFIG_SYS_OMAP24_I2C_SLAVE2 slave addr channel 2
1662 - CONFIG_SYS_OMAP24_I2C_SPEED3 speed channel 3
1663 - CONFIG_SYS_OMAP24_I2C_SLAVE3 slave addr channel 3
1664 - CONFIG_SYS_OMAP24_I2C_SPEED4 speed channel 4
1665 - CONFIG_SYS_OMAP24_I2C_SLAVE4 slave addr channel 4
1666
Naveen Krishna Ch5d5efd32013-12-06 12:12:38 +05301667 - drivers/i2c/s3c24x0_i2c.c:
1668 - activate this driver with CONFIG_SYS_I2C_S3C24X0
1669 - This driver adds i2c buses (11 for Exynos5250, Exynos5420
1670 9 i2c buses for Exynos4 and 1 for S3C24X0 SoCs from Samsung)
1671 with a fix speed from 100000 and the slave addr 0!
1672
Dirk Eibachb9577432014-07-03 09:28:18 +02001673 - drivers/i2c/ihs_i2c.c
1674 - activate this driver with CONFIG_SYS_I2C_IHS
1675 - CONFIG_SYS_I2C_IHS_CH0 activate hardware channel 0
1676 - CONFIG_SYS_I2C_IHS_SPEED_0 speed channel 0
1677 - CONFIG_SYS_I2C_IHS_SLAVE_0 slave addr channel 0
1678 - CONFIG_SYS_I2C_IHS_CH1 activate hardware channel 1
1679 - CONFIG_SYS_I2C_IHS_SPEED_1 speed channel 1
1680 - CONFIG_SYS_I2C_IHS_SLAVE_1 slave addr channel 1
1681 - CONFIG_SYS_I2C_IHS_CH2 activate hardware channel 2
1682 - CONFIG_SYS_I2C_IHS_SPEED_2 speed channel 2
1683 - CONFIG_SYS_I2C_IHS_SLAVE_2 slave addr channel 2
1684 - CONFIG_SYS_I2C_IHS_CH3 activate hardware channel 3
1685 - CONFIG_SYS_I2C_IHS_SPEED_3 speed channel 3
1686 - CONFIG_SYS_I2C_IHS_SLAVE_3 slave addr channel 3
Dirk Eibach9ac33852015-10-28 11:46:22 +01001687 - activate dual channel with CONFIG_SYS_I2C_IHS_DUAL
1688 - CONFIG_SYS_I2C_IHS_SPEED_0_1 speed channel 0_1
1689 - CONFIG_SYS_I2C_IHS_SLAVE_0_1 slave addr channel 0_1
1690 - CONFIG_SYS_I2C_IHS_SPEED_1_1 speed channel 1_1
1691 - CONFIG_SYS_I2C_IHS_SLAVE_1_1 slave addr channel 1_1
1692 - CONFIG_SYS_I2C_IHS_SPEED_2_1 speed channel 2_1
1693 - CONFIG_SYS_I2C_IHS_SLAVE_2_1 slave addr channel 2_1
1694 - CONFIG_SYS_I2C_IHS_SPEED_3_1 speed channel 3_1
1695 - CONFIG_SYS_I2C_IHS_SLAVE_3_1 slave addr channel 3_1
Dirk Eibachb9577432014-07-03 09:28:18 +02001696
Heiko Schochere0e55bc2012-01-16 21:12:24 +00001697 additional defines:
1698
1699 CONFIG_SYS_NUM_I2C_BUSES
Simon Glassb05e2b32016-10-02 18:01:05 -06001700 Hold the number of i2c buses you want to use.
Heiko Schochere0e55bc2012-01-16 21:12:24 +00001701
1702 CONFIG_SYS_I2C_DIRECT_BUS
1703 define this, if you don't use i2c muxes on your hardware.
1704 if CONFIG_SYS_I2C_MAX_HOPS is not defined or == 0 you can
1705 omit this define.
1706
1707 CONFIG_SYS_I2C_MAX_HOPS
1708 define how many muxes are maximal consecutively connected
1709 on one i2c bus. If you not use i2c muxes, omit this
1710 define.
1711
1712 CONFIG_SYS_I2C_BUSES
Jeremiah Mahler03f930c2015-01-04 18:56:50 -08001713 hold a list of buses you want to use, only used if
Heiko Schochere0e55bc2012-01-16 21:12:24 +00001714 CONFIG_SYS_I2C_DIRECT_BUS is not defined, for example
1715 a board with CONFIG_SYS_I2C_MAX_HOPS = 1 and
1716 CONFIG_SYS_NUM_I2C_BUSES = 9:
1717
1718 CONFIG_SYS_I2C_BUSES {{0, {I2C_NULL_HOP}}, \
1719 {0, {{I2C_MUX_PCA9547, 0x70, 1}}}, \
1720 {0, {{I2C_MUX_PCA9547, 0x70, 2}}}, \
1721 {0, {{I2C_MUX_PCA9547, 0x70, 3}}}, \
1722 {0, {{I2C_MUX_PCA9547, 0x70, 4}}}, \
1723 {0, {{I2C_MUX_PCA9547, 0x70, 5}}}, \
1724 {1, {I2C_NULL_HOP}}, \
1725 {1, {{I2C_MUX_PCA9544, 0x72, 1}}}, \
1726 {1, {{I2C_MUX_PCA9544, 0x72, 2}}}, \
1727 }
1728
1729 which defines
1730 bus 0 on adapter 0 without a mux
Heiko Schocher479a4cf2013-01-29 08:53:15 +01001731 bus 1 on adapter 0 with a PCA9547 on address 0x70 port 1
1732 bus 2 on adapter 0 with a PCA9547 on address 0x70 port 2
1733 bus 3 on adapter 0 with a PCA9547 on address 0x70 port 3
1734 bus 4 on adapter 0 with a PCA9547 on address 0x70 port 4
1735 bus 5 on adapter 0 with a PCA9547 on address 0x70 port 5
Heiko Schochere0e55bc2012-01-16 21:12:24 +00001736 bus 6 on adapter 1 without a mux
Heiko Schocher479a4cf2013-01-29 08:53:15 +01001737 bus 7 on adapter 1 with a PCA9544 on address 0x72 port 1
1738 bus 8 on adapter 1 with a PCA9544 on address 0x72 port 2
Heiko Schochere0e55bc2012-01-16 21:12:24 +00001739
1740 If you do not have i2c muxes on your board, omit this define.
1741
Simon Glass3efce392017-05-12 21:10:00 -06001742- Legacy I2C Support:
Heiko Schocher479a4cf2013-01-29 08:53:15 +01001743 If you use the software i2c interface (CONFIG_SYS_I2C_SOFT)
wdenkb9bbd242003-06-30 16:24:52 +00001744 then the following macros need to be defined (examples are
1745 from include/configs/lwmon.h):
wdenkc6097192002-11-03 00:24:07 +00001746
1747 I2C_INIT
1748
wdenkb9bbd242003-06-30 16:24:52 +00001749 (Optional). Any commands necessary to enable the I2C
wdenk4a5c8a72003-03-06 00:02:04 +00001750 controller or configure ports.
wdenkc6097192002-11-03 00:24:07 +00001751
wdenk544e9732004-02-06 23:19:44 +00001752 eg: #define I2C_INIT (immr->im_cpm.cp_pbdir |= PB_SCL)
wdenkb9bbd242003-06-30 16:24:52 +00001753
wdenkc6097192002-11-03 00:24:07 +00001754 I2C_ACTIVE
1755
1756 The code necessary to make the I2C data line active
1757 (driven). If the data line is open collector, this
1758 define can be null.
1759
wdenkb9bbd242003-06-30 16:24:52 +00001760 eg: #define I2C_ACTIVE (immr->im_cpm.cp_pbdir |= PB_SDA)
1761
wdenkc6097192002-11-03 00:24:07 +00001762 I2C_TRISTATE
1763
1764 The code necessary to make the I2C data line tri-stated
1765 (inactive). If the data line is open collector, this
1766 define can be null.
1767
wdenkb9bbd242003-06-30 16:24:52 +00001768 eg: #define I2C_TRISTATE (immr->im_cpm.cp_pbdir &= ~PB_SDA)
1769
wdenkc6097192002-11-03 00:24:07 +00001770 I2C_READ
1771
York Sun4a598092013-04-01 11:29:11 -07001772 Code that returns true if the I2C data line is high,
1773 false if it is low.
wdenkc6097192002-11-03 00:24:07 +00001774
wdenkb9bbd242003-06-30 16:24:52 +00001775 eg: #define I2C_READ ((immr->im_cpm.cp_pbdat & PB_SDA) != 0)
1776
wdenkc6097192002-11-03 00:24:07 +00001777 I2C_SDA(bit)
1778
York Sun4a598092013-04-01 11:29:11 -07001779 If <bit> is true, sets the I2C data line high. If it
1780 is false, it clears it (low).
wdenkc6097192002-11-03 00:24:07 +00001781
wdenkb9bbd242003-06-30 16:24:52 +00001782 eg: #define I2C_SDA(bit) \
wdenk2bb11052003-07-17 23:16:40 +00001783 if(bit) immr->im_cpm.cp_pbdat |= PB_SDA; \
wdenk544e9732004-02-06 23:19:44 +00001784 else immr->im_cpm.cp_pbdat &= ~PB_SDA
wdenkb9bbd242003-06-30 16:24:52 +00001785
wdenkc6097192002-11-03 00:24:07 +00001786 I2C_SCL(bit)
1787
York Sun4a598092013-04-01 11:29:11 -07001788 If <bit> is true, sets the I2C clock line high. If it
1789 is false, it clears it (low).
wdenkc6097192002-11-03 00:24:07 +00001790
wdenkb9bbd242003-06-30 16:24:52 +00001791 eg: #define I2C_SCL(bit) \
wdenk2bb11052003-07-17 23:16:40 +00001792 if(bit) immr->im_cpm.cp_pbdat |= PB_SCL; \
wdenk544e9732004-02-06 23:19:44 +00001793 else immr->im_cpm.cp_pbdat &= ~PB_SCL
wdenkb9bbd242003-06-30 16:24:52 +00001794
wdenkc6097192002-11-03 00:24:07 +00001795 I2C_DELAY
1796
1797 This delay is invoked four times per clock cycle so this
1798 controls the rate of data transfer. The data rate thus
wdenkb9bbd242003-06-30 16:24:52 +00001799 is 1 / (I2C_DELAY * 4). Often defined to be something
wdenk21136db2003-07-16 21:53:01 +00001800 like:
1801
wdenkb9bbd242003-06-30 16:24:52 +00001802 #define I2C_DELAY udelay(2)
wdenkc6097192002-11-03 00:24:07 +00001803
Mike Frysingeree12d542010-07-21 13:38:02 -04001804 CONFIG_SOFT_I2C_GPIO_SCL / CONFIG_SOFT_I2C_GPIO_SDA
1805
1806 If your arch supports the generic GPIO framework (asm/gpio.h),
1807 then you may alternatively define the two GPIOs that are to be
1808 used as SCL / SDA. Any of the previous I2C_xxx macros will
1809 have GPIO-based defaults assigned to them as appropriate.
1810
1811 You should define these to the GPIO value as given directly to
1812 the generic GPIO functions.
1813
Jean-Christophe PLAGNIOL-VILLARD03836942008-10-16 15:01:15 +02001814 CONFIG_SYS_I2C_INIT_BOARD
wdenkcc1e2562003-03-06 13:39:27 +00001815
wdenk57b2d802003-06-27 21:31:46 +00001816 When a board is reset during an i2c bus transfer
1817 chips might think that the current transfer is still
1818 in progress. On some boards it is possible to access
1819 the i2c SCLK line directly, either by using the
1820 processor pin as a GPIO or by having a second pin
1821 connected to the bus. If this option is defined a
1822 custom i2c_init_board() routine in boards/xxx/board.c
1823 is run early in the boot sequence.
wdenkcc1e2562003-03-06 13:39:27 +00001824
Ben Warren45657152006-09-07 16:50:54 -04001825 CONFIG_I2C_MULTI_BUS
1826
1827 This option allows the use of multiple I2C buses, each of which
Wolfgang Denk092ae952011-10-26 10:21:21 +00001828 must have a controller. At any point in time, only one bus is
1829 active. To switch to a different bus, use the 'i2c dev' command.
Ben Warren45657152006-09-07 16:50:54 -04001830 Note that bus numbering is zero-based.
1831
Jean-Christophe PLAGNIOL-VILLARD03836942008-10-16 15:01:15 +02001832 CONFIG_SYS_I2C_NOPROBES
Ben Warren45657152006-09-07 16:50:54 -04001833
1834 This option specifies a list of I2C devices that will be skipped
Wolfgang Denk092ae952011-10-26 10:21:21 +00001835 when the 'i2c probe' command is issued. If CONFIG_I2C_MULTI_BUS
Peter Tyser469cde42009-04-18 22:34:03 -05001836 is set, specify a list of bus-device pairs. Otherwise, specify
1837 a 1D array of device addresses
Ben Warren45657152006-09-07 16:50:54 -04001838
1839 e.g.
1840 #undef CONFIG_I2C_MULTI_BUS
Wolfgang Denk092ae952011-10-26 10:21:21 +00001841 #define CONFIG_SYS_I2C_NOPROBES {0x50,0x68}
Ben Warren45657152006-09-07 16:50:54 -04001842
1843 will skip addresses 0x50 and 0x68 on a board with one I2C bus
1844
Wolfgang Denk092ae952011-10-26 10:21:21 +00001845 #define CONFIG_I2C_MULTI_BUS
Simon Glassb05e2b32016-10-02 18:01:05 -06001846 #define CONFIG_SYS_I2C_NOPROBES {{0,0x50},{0,0x68},{1,0x54}}
Ben Warren45657152006-09-07 16:50:54 -04001847
1848 will skip addresses 0x50 and 0x68 on bus 0 and address 0x54 on bus 1
1849
Jean-Christophe PLAGNIOL-VILLARD03836942008-10-16 15:01:15 +02001850 CONFIG_SYS_SPD_BUS_NUM
Timur Tabiab347542006-11-03 19:15:00 -06001851
1852 If defined, then this indicates the I2C bus number for DDR SPD.
1853 If not defined, then U-Boot assumes that SPD is on I2C bus 0.
1854
Jean-Christophe PLAGNIOL-VILLARD03836942008-10-16 15:01:15 +02001855 CONFIG_SYS_RTC_BUS_NUM
Stefan Roese096cc9b2007-02-20 10:51:26 +01001856
1857 If defined, then this indicates the I2C bus number for the RTC.
1858 If not defined, then U-Boot assumes that RTC is on I2C bus 0.
1859
Andrew Dyer58c41f92008-12-29 17:36:01 -06001860 CONFIG_SOFT_I2C_READ_REPEATED_START
1861
1862 defining this will force the i2c_read() function in
1863 the soft_i2c driver to perform an I2C repeated start
1864 between writing the address pointer and reading the
1865 data. If this define is omitted the default behaviour
1866 of doing a stop-start sequence will be used. Most I2C
1867 devices can use either method, but some require one or
1868 the other.
Timur Tabiab347542006-11-03 19:15:00 -06001869
wdenkc6097192002-11-03 00:24:07 +00001870- SPI Support: CONFIG_SPI
1871
1872 Enables SPI driver (so far only tested with
1873 SPI EEPROM, also an instance works with Crystal A/D and
1874 D/As on the SACSng board)
1875
wdenkc6097192002-11-03 00:24:07 +00001876 CONFIG_SOFT_SPI
1877
wdenk4a5c8a72003-03-06 00:02:04 +00001878 Enables a software (bit-bang) SPI driver rather than
1879 using hardware support. This is a general purpose
1880 driver that only requires three general I/O port pins
1881 (two outputs, one input) to function. If this is
1882 defined, the board configuration must define several
1883 SPI configuration items (port pins to use, etc). For
1884 an example, see include/configs/sacsng.h.
wdenkc6097192002-11-03 00:24:07 +00001885
Heiko Schocherb77c8882014-07-14 10:22:11 +02001886 CONFIG_SYS_SPI_MXC_WAIT
1887 Timeout for waiting until spi transfer completed.
1888 default: (CONFIG_SYS_HZ/100) /* 10 ms */
1889
Matthias Fuchsa4400872007-12-27 17:12:34 +01001890- FPGA Support: CONFIG_FPGA
wdenkc6097192002-11-03 00:24:07 +00001891
Matthias Fuchsa4400872007-12-27 17:12:34 +01001892 Enables FPGA subsystem.
1893
1894 CONFIG_FPGA_<vendor>
1895
1896 Enables support for specific chip vendors.
1897 (ALTERA, XILINX)
wdenkc6097192002-11-03 00:24:07 +00001898
Matthias Fuchsa4400872007-12-27 17:12:34 +01001899 CONFIG_FPGA_<family>
wdenkc6097192002-11-03 00:24:07 +00001900
Matthias Fuchsa4400872007-12-27 17:12:34 +01001901 Enables support for FPGA family.
1902 (SPARTAN2, SPARTAN3, VIRTEX2, CYCLONE2, ACEX1K, ACEX)
1903
1904 CONFIG_FPGA_COUNT
1905
1906 Specify the number of FPGA devices to support.
wdenkc6097192002-11-03 00:24:07 +00001907
Jean-Christophe PLAGNIOL-VILLARD03836942008-10-16 15:01:15 +02001908 CONFIG_SYS_FPGA_PROG_FEEDBACK
wdenkc6097192002-11-03 00:24:07 +00001909
wdenk57b2d802003-06-27 21:31:46 +00001910 Enable printing of hash marks during FPGA configuration.
wdenkc6097192002-11-03 00:24:07 +00001911
Jean-Christophe PLAGNIOL-VILLARD03836942008-10-16 15:01:15 +02001912 CONFIG_SYS_FPGA_CHECK_BUSY
wdenkc6097192002-11-03 00:24:07 +00001913
wdenk4a5c8a72003-03-06 00:02:04 +00001914 Enable checks on FPGA configuration interface busy
1915 status by the configuration function. This option
1916 will require a board or device specific function to
1917 be written.
wdenkc6097192002-11-03 00:24:07 +00001918
1919 CONFIG_FPGA_DELAY
1920
1921 If defined, a function that provides delays in the FPGA
1922 configuration driver.
1923
Jean-Christophe PLAGNIOL-VILLARD03836942008-10-16 15:01:15 +02001924 CONFIG_SYS_FPGA_CHECK_CTRLC
wdenkc6097192002-11-03 00:24:07 +00001925 Allow Control-C to interrupt FPGA configuration
1926
Jean-Christophe PLAGNIOL-VILLARD03836942008-10-16 15:01:15 +02001927 CONFIG_SYS_FPGA_CHECK_ERROR
wdenkc6097192002-11-03 00:24:07 +00001928
wdenk4a5c8a72003-03-06 00:02:04 +00001929 Check for configuration errors during FPGA bitfile
1930 loading. For example, abort during Virtex II
1931 configuration if the INIT_B line goes low (which
1932 indicated a CRC error).
wdenkc6097192002-11-03 00:24:07 +00001933
Jean-Christophe PLAGNIOL-VILLARD03836942008-10-16 15:01:15 +02001934 CONFIG_SYS_FPGA_WAIT_INIT
wdenkc6097192002-11-03 00:24:07 +00001935
Jeremiah Mahler03f930c2015-01-04 18:56:50 -08001936 Maximum time to wait for the INIT_B line to de-assert
1937 after PROB_B has been de-asserted during a Virtex II
wdenk4a5c8a72003-03-06 00:02:04 +00001938 FPGA configuration sequence. The default time is 500
Marcel Ziswilerabd8dcb2008-07-09 08:17:15 +02001939 ms.
wdenkc6097192002-11-03 00:24:07 +00001940
Jean-Christophe PLAGNIOL-VILLARD03836942008-10-16 15:01:15 +02001941 CONFIG_SYS_FPGA_WAIT_BUSY
wdenkc6097192002-11-03 00:24:07 +00001942
Jeremiah Mahler03f930c2015-01-04 18:56:50 -08001943 Maximum time to wait for BUSY to de-assert during
Marcel Ziswilerabd8dcb2008-07-09 08:17:15 +02001944 Virtex II FPGA configuration. The default is 5 ms.
wdenkc6097192002-11-03 00:24:07 +00001945
Jean-Christophe PLAGNIOL-VILLARD03836942008-10-16 15:01:15 +02001946 CONFIG_SYS_FPGA_WAIT_CONFIG
wdenkc6097192002-11-03 00:24:07 +00001947
wdenk4a5c8a72003-03-06 00:02:04 +00001948 Time to wait after FPGA configuration. The default is
Marcel Ziswilerabd8dcb2008-07-09 08:17:15 +02001949 200 ms.
wdenkc6097192002-11-03 00:24:07 +00001950
1951- Configuration Management:
Stefan Roese141ed202014-10-22 12:13:24 +02001952
wdenkc6097192002-11-03 00:24:07 +00001953 CONFIG_IDENT_STRING
1954
wdenk4a5c8a72003-03-06 00:02:04 +00001955 If defined, this string will be added to the U-Boot
1956 version information (U_BOOT_VERSION)
wdenkc6097192002-11-03 00:24:07 +00001957
1958- Vendor Parameter Protection:
1959
wdenk4a5c8a72003-03-06 00:02:04 +00001960 U-Boot considers the values of the environment
1961 variables "serial#" (Board Serial Number) and
wdenkeb20ad32003-09-05 23:19:14 +00001962 "ethaddr" (Ethernet Address) to be parameters that
wdenk4a5c8a72003-03-06 00:02:04 +00001963 are set once by the board vendor / manufacturer, and
1964 protects these variables from casual modification by
1965 the user. Once set, these variables are read-only,
1966 and write or delete attempts are rejected. You can
Marcel Ziswilerabd8dcb2008-07-09 08:17:15 +02001967 change this behaviour:
wdenkc6097192002-11-03 00:24:07 +00001968
1969 If CONFIG_ENV_OVERWRITE is #defined in your config
1970 file, the write protection for vendor parameters is
wdenkcc1e2562003-03-06 13:39:27 +00001971 completely disabled. Anybody can change or delete
wdenkc6097192002-11-03 00:24:07 +00001972 these parameters.
1973
Joe Hershberger76f353e2015-05-04 14:55:14 -05001974 Alternatively, if you define _both_ an ethaddr in the
1975 default env _and_ CONFIG_OVERWRITE_ETHADDR_ONCE, a default
Marcel Ziswilerabd8dcb2008-07-09 08:17:15 +02001976 Ethernet address is installed in the environment,
wdenkc6097192002-11-03 00:24:07 +00001977 which can be changed exactly ONCE by the user. [The
1978 serial# is unaffected by this, i. e. it remains
1979 read-only.]
1980
Joe Hershberger71497d02012-12-11 22:16:31 -06001981 The same can be accomplished in a more flexible way
1982 for any variable by configuring the type of access
1983 to allow for those variables in the ".flags" variable
1984 or define CONFIG_ENV_FLAGS_LIST_STATIC.
1985
wdenkc6097192002-11-03 00:24:07 +00001986- Protected RAM:
1987 CONFIG_PRAM
1988
1989 Define this variable to enable the reservation of
1990 "protected RAM", i. e. RAM which is not overwritten
1991 by U-Boot. Define CONFIG_PRAM to hold the number of
1992 kB you want to reserve for pRAM. You can overwrite
1993 this default value by defining an environment
1994 variable "pram" to the number of kB you want to
1995 reserve. Note that the board info structure will
1996 still show the full amount of RAM. If pRAM is
1997 reserved, a new environment variable "mem" will
1998 automatically be defined to hold the amount of
1999 remaining RAM in a form that can be passed as boot
2000 argument to Linux, for instance like that:
2001
Wolfgang Denk86eb3b72005-11-20 21:40:11 +01002002 setenv bootargs ... mem=\${mem}
wdenkc6097192002-11-03 00:24:07 +00002003 saveenv
2004
2005 This way you can tell Linux not to use this memory,
2006 either, which results in a memory region that will
2007 not be affected by reboots.
2008
2009 *WARNING* If your board configuration uses automatic
2010 detection of the RAM size, you must make sure that
2011 this memory test is non-destructive. So far, the
2012 following board configurations are known to be
2013 "pRAM-clean":
2014
Heiko Schocher65d94db2017-06-07 17:33:09 +02002015 IVMS8, IVML24, SPD8xx,
Wolfgang Denk90326762012-10-24 02:36:15 +00002016 HERMES, IP860, RPXlite, LWMON,
Heiko Schocher71cb3e92017-06-07 17:33:10 +02002017 FLAGADM
wdenkc6097192002-11-03 00:24:07 +00002018
Gabe Blacka2f3a932012-12-02 04:55:18 +00002019- Access to physical memory region (> 4GB)
2020 Some basic support is provided for operations on memory not
2021 normally accessible to U-Boot - e.g. some architectures
2022 support access to more than 4GB of memory on 32-bit
2023 machines using physical address extension or similar.
2024 Define CONFIG_PHYSMEM to access this basic support, which
2025 currently only supports clearing the memory.
2026
wdenkc6097192002-11-03 00:24:07 +00002027- Error Recovery:
wdenkc6097192002-11-03 00:24:07 +00002028 CONFIG_NET_RETRY_COUNT
2029
wdenk4a5c8a72003-03-06 00:02:04 +00002030 This variable defines the number of retries for
2031 network operations like ARP, RARP, TFTP, or BOOTP
2032 before giving up the operation. If not defined, a
2033 default value of 5 is used.
wdenkc6097192002-11-03 00:24:07 +00002034
Guennadi Liakhovetskib38c2b32008-04-03 17:04:19 +02002035 CONFIG_ARP_TIMEOUT
2036
2037 Timeout waiting for an ARP reply in milliseconds.
2038
Tetsuyuki Kobayashi147e3902012-07-03 22:25:21 +00002039 CONFIG_NFS_TIMEOUT
2040
2041 Timeout in milliseconds used in NFS protocol.
2042 If you encounter "ERROR: Cannot umount" in nfs command,
2043 try longer timeout such as
2044 #define CONFIG_NFS_TIMEOUT 10000UL
2045
wdenkc6097192002-11-03 00:24:07 +00002046- Command Interpreter:
Jean-Christophe PLAGNIOL-VILLARD03836942008-10-16 15:01:15 +02002047 CONFIG_SYS_PROMPT_HUSH_PS2
wdenkc6097192002-11-03 00:24:07 +00002048
2049 This defines the secondary prompt string, which is
2050 printed when the command interpreter needs more input
2051 to complete a command. Usually "> ".
2052
2053 Note:
2054
wdenk57b2d802003-06-27 21:31:46 +00002055 In the current implementation, the local variables
2056 space and global environment variables space are
2057 separated. Local variables are those you define by
2058 simply typing `name=value'. To access a local
2059 variable later on, you have write `$name' or
2060 `${name}'; to execute the contents of a variable
2061 directly type `$name' at the command prompt.
wdenkc6097192002-11-03 00:24:07 +00002062
wdenk4a5c8a72003-03-06 00:02:04 +00002063 Global environment variables are those you use
2064 setenv/printenv to work with. To run a command stored
2065 in such a variable, you need to use the run command,
2066 and you must not use the '$' sign to access them.
wdenkc6097192002-11-03 00:24:07 +00002067
2068 To store commands and special characters in a
2069 variable, please use double quotation marks
2070 surrounding the whole text of the variable, instead
2071 of the backslashes before semicolons and special
2072 symbols.
2073
Jeremiah Mahler03f930c2015-01-04 18:56:50 -08002074- Command Line Editing and History:
Marek Vasut734fb042016-01-27 04:47:55 +01002075 CONFIG_CMDLINE_PS_SUPPORT
2076
2077 Enable support for changing the command prompt string
2078 at run-time. Only static string is supported so far.
2079 The string is obtained from environment variables PS1
2080 and PS2.
2081
wdenkc0aa5c52003-12-06 19:49:23 +00002082- Default Environment:
wdenkc6097192002-11-03 00:24:07 +00002083 CONFIG_EXTRA_ENV_SETTINGS
2084
wdenk4a5c8a72003-03-06 00:02:04 +00002085 Define this to contain any number of null terminated
2086 strings (variable = value pairs) that will be part of
wdenkeb20ad32003-09-05 23:19:14 +00002087 the default environment compiled into the boot image.
wdenk591dda52002-11-18 00:14:45 +00002088
wdenk4a5c8a72003-03-06 00:02:04 +00002089 For example, place something like this in your
2090 board's config file:
wdenkc6097192002-11-03 00:24:07 +00002091
2092 #define CONFIG_EXTRA_ENV_SETTINGS \
2093 "myvar1=value1\0" \
2094 "myvar2=value2\0"
2095
wdenk4a5c8a72003-03-06 00:02:04 +00002096 Warning: This method is based on knowledge about the
2097 internal format how the environment is stored by the
2098 U-Boot code. This is NOT an official, exported
2099 interface! Although it is unlikely that this format
wdenkeb20ad32003-09-05 23:19:14 +00002100 will change soon, there is no guarantee either.
wdenkc6097192002-11-03 00:24:07 +00002101 You better know what you are doing here.
2102
wdenk4a5c8a72003-03-06 00:02:04 +00002103 Note: overly (ab)use of the default environment is
2104 discouraged. Make sure to check other ways to preset
Wolfgang Denk85c25df2009-04-01 23:34:12 +02002105 the environment like the "source" command or the
wdenk4a5c8a72003-03-06 00:02:04 +00002106 boot command first.
wdenkc6097192002-11-03 00:24:07 +00002107
Simon Glass6b8d5fd2012-11-30 13:01:17 +00002108 CONFIG_DELAY_ENVIRONMENT
2109
2110 Normally the environment is loaded when the board is
Jeremiah Mahler03f930c2015-01-04 18:56:50 -08002111 initialised so that it is available to U-Boot. This inhibits
Simon Glass6b8d5fd2012-11-30 13:01:17 +00002112 that so that the environment is not available until
2113 explicitly loaded later by U-Boot code. With CONFIG_OF_CONTROL
2114 this is instead controlled by the value of
2115 /config/load-environment.
2116
Wolfgang Denke3cfce52005-09-24 22:37:32 +02002117- TFTP Fixed UDP Port:
2118 CONFIG_TFTP_PORT
2119
Wolfgang Denk227b5192005-09-24 23:25:46 +02002120 If this is defined, the environment variable tftpsrcp
Wolfgang Denke3cfce52005-09-24 22:37:32 +02002121 is used to supply the TFTP UDP source port value.
Wolfgang Denk227b5192005-09-24 23:25:46 +02002122 If tftpsrcp isn't defined, the normal pseudo-random port
Wolfgang Denke3cfce52005-09-24 22:37:32 +02002123 number generator is used.
2124
Wolfgang Denk227b5192005-09-24 23:25:46 +02002125 Also, the environment variable tftpdstp is used to supply
2126 the TFTP UDP destination port value. If tftpdstp isn't
2127 defined, the normal port 69 is used.
2128
2129 The purpose for tftpsrcp is to allow a TFTP server to
Wolfgang Denke3cfce52005-09-24 22:37:32 +02002130 blindly start the TFTP transfer using the pre-configured
2131 target IP address and UDP port. This has the effect of
2132 "punching through" the (Windows XP) firewall, allowing
2133 the remainder of the TFTP transfer to proceed normally.
2134 A better solution is to properly configure the firewall,
2135 but sometimes that is not allowed.
2136
Wolfgang Denkd590fb12011-10-07 09:58:21 +02002137 CONFIG_STANDALONE_LOAD_ADDR
2138
Wolfgang Denk23f78482011-10-09 21:06:34 +02002139 This option defines a board specific value for the
2140 address where standalone program gets loaded, thus
2141 overwriting the architecture dependent default
Wolfgang Denkd590fb12011-10-07 09:58:21 +02002142 settings.
2143
2144- Frame Buffer Address:
2145 CONFIG_FB_ADDR
2146
2147 Define CONFIG_FB_ADDR if you want to use specific
Wolfgang Denka71eb8e2013-01-03 00:43:59 +00002148 address for frame buffer. This is typically the case
2149 when using a graphics controller has separate video
2150 memory. U-Boot will then place the frame buffer at
2151 the given address instead of dynamically reserving it
2152 in system RAM by calling lcd_setmem(), which grabs
2153 the memory for the frame buffer depending on the
2154 configured panel size.
Wolfgang Denkd590fb12011-10-07 09:58:21 +02002155
2156 Please see board_init_f function.
2157
Detlev Zundel0ecb6112009-12-01 17:16:19 +01002158- Automatic software updates via TFTP server
2159 CONFIG_UPDATE_TFTP
2160 CONFIG_UPDATE_TFTP_CNT_MAX
2161 CONFIG_UPDATE_TFTP_MSEC_MAX
2162
2163 These options enable and control the auto-update feature;
2164 for a more detailed description refer to doc/README.update.
2165
2166- MTD Support (mtdparts command, UBI support)
Heiko Schocherf5895d12014-06-24 10:10:04 +02002167 CONFIG_MTD_UBI_WL_THRESHOLD
2168 This parameter defines the maximum difference between the highest
2169 erase counter value and the lowest erase counter value of eraseblocks
2170 of UBI devices. When this threshold is exceeded, UBI starts performing
2171 wear leveling by means of moving data from eraseblock with low erase
2172 counter to eraseblocks with high erase counter.
2173
2174 The default value should be OK for SLC NAND flashes, NOR flashes and
2175 other flashes which have eraseblock life-cycle 100000 or more.
2176 However, in case of MLC NAND flashes which typically have eraseblock
2177 life-cycle less than 10000, the threshold should be lessened (e.g.,
2178 to 128 or 256, although it does not have to be power of 2).
2179
2180 default: 4096
Simon Glass6c0be912014-10-23 18:58:54 -06002181
Heiko Schocherf5895d12014-06-24 10:10:04 +02002182 CONFIG_MTD_UBI_BEB_LIMIT
2183 This option specifies the maximum bad physical eraseblocks UBI
2184 expects on the MTD device (per 1024 eraseblocks). If the
2185 underlying flash does not admit of bad eraseblocks (e.g. NOR
2186 flash), this value is ignored.
2187
2188 NAND datasheets often specify the minimum and maximum NVM
2189 (Number of Valid Blocks) for the flashes' endurance lifetime.
2190 The maximum expected bad eraseblocks per 1024 eraseblocks
2191 then can be calculated as "1024 * (1 - MinNVB / MaxNVB)",
2192 which gives 20 for most NANDs (MaxNVB is basically the total
2193 count of eraseblocks on the chip).
2194
2195 To put it differently, if this value is 20, UBI will try to
2196 reserve about 1.9% of physical eraseblocks for bad blocks
2197 handling. And that will be 1.9% of eraseblocks on the entire
2198 NAND chip, not just the MTD partition UBI attaches. This means
2199 that if you have, say, a NAND flash chip admits maximum 40 bad
2200 eraseblocks, and it is split on two MTD partitions of the same
2201 size, UBI will reserve 40 eraseblocks when attaching a
2202 partition.
2203
2204 default: 20
2205
2206 CONFIG_MTD_UBI_FASTMAP
2207 Fastmap is a mechanism which allows attaching an UBI device
2208 in nearly constant time. Instead of scanning the whole MTD device it
2209 only has to locate a checkpoint (called fastmap) on the device.
2210 The on-flash fastmap contains all information needed to attach
2211 the device. Using fastmap makes only sense on large devices where
2212 attaching by scanning takes long. UBI will not automatically install
2213 a fastmap on old images, but you can set the UBI parameter
2214 CONFIG_MTD_UBI_FASTMAP_AUTOCONVERT to 1 if you want so. Please note
2215 that fastmap-enabled images are still usable with UBI implementations
2216 without fastmap support. On typical flash devices the whole fastmap
2217 fits into one PEB. UBI will reserve PEBs to hold two fastmaps.
2218
2219 CONFIG_MTD_UBI_FASTMAP_AUTOCONVERT
2220 Set this parameter to enable fastmap automatically on images
2221 without a fastmap.
2222 default: 0
2223
Heiko Schocher94b66de2015-10-22 06:19:21 +02002224 CONFIG_MTD_UBI_FM_DEBUG
2225 Enable UBI fastmap debug
2226 default: 0
2227
Daniel Schwierzeck39ca08e2011-07-18 07:48:07 +00002228- SPL framework
Wolfgang Denk825223d2011-09-11 21:24:09 +02002229 CONFIG_SPL
2230 Enable building of SPL globally.
Daniel Schwierzeck39ca08e2011-07-18 07:48:07 +00002231
Tom Rini36853852012-02-14 07:29:40 +00002232 CONFIG_SPL_LDSCRIPT
2233 LDSCRIPT for linking the SPL binary.
2234
Albert ARIBAUDe916e052013-04-12 05:14:30 +00002235 CONFIG_SPL_MAX_FOOTPRINT
2236 Maximum size in memory allocated to the SPL, BSS included.
2237 When defined, the linker checks that the actual memory
2238 used by SPL from _start to __bss_end does not exceed it.
Albert ARIBAUDafab1482013-04-14 04:48:38 +00002239 CONFIG_SPL_MAX_FOOTPRINT and CONFIG_SPL_BSS_MAX_SIZE
Albert ARIBAUDe916e052013-04-12 05:14:30 +00002240 must not be both defined at the same time.
2241
Tom Rini36853852012-02-14 07:29:40 +00002242 CONFIG_SPL_MAX_SIZE
Albert ARIBAUDe916e052013-04-12 05:14:30 +00002243 Maximum size of the SPL image (text, data, rodata, and
2244 linker lists sections), BSS excluded.
2245 When defined, the linker checks that the actual size does
2246 not exceed it.
Tom Rini36853852012-02-14 07:29:40 +00002247
Scott Woodc4f0d002012-09-20 19:05:12 -05002248 CONFIG_SPL_RELOC_TEXT_BASE
2249 Address to relocate to. If unspecified, this is equal to
2250 CONFIG_SPL_TEXT_BASE (i.e. no relocation is done).
2251
Tom Rini36853852012-02-14 07:29:40 +00002252 CONFIG_SPL_BSS_START_ADDR
2253 Link address for the BSS within the SPL binary.
2254
2255 CONFIG_SPL_BSS_MAX_SIZE
Albert ARIBAUDe916e052013-04-12 05:14:30 +00002256 Maximum size in memory allocated to the SPL BSS.
2257 When defined, the linker checks that the actual memory used
2258 by SPL from __bss_start to __bss_end does not exceed it.
Albert ARIBAUDafab1482013-04-14 04:48:38 +00002259 CONFIG_SPL_MAX_FOOTPRINT and CONFIG_SPL_BSS_MAX_SIZE
Albert ARIBAUDe916e052013-04-12 05:14:30 +00002260 must not be both defined at the same time.
Tom Rini36853852012-02-14 07:29:40 +00002261
2262 CONFIG_SPL_STACK
2263 Adress of the start of the stack SPL will use
2264
Albert ARIBAUD \(3ADEV\)287b0942015-03-31 11:40:50 +02002265 CONFIG_SPL_PANIC_ON_RAW_IMAGE
2266 When defined, SPL will panic() if the image it has
2267 loaded does not have a signature.
2268 Defining this is useful when code which loads images
2269 in SPL cannot guarantee that absolutely all read errors
2270 will be caught.
2271 An example is the LPC32XX MLC NAND driver, which will
2272 consider that a completely unreadable NAND block is bad,
2273 and thus should be skipped silently.
2274
Scott Woodc4f0d002012-09-20 19:05:12 -05002275 CONFIG_SPL_RELOC_STACK
2276 Adress of the start of the stack SPL will use after
2277 relocation. If unspecified, this is equal to
2278 CONFIG_SPL_STACK.
2279
Tom Rini36853852012-02-14 07:29:40 +00002280 CONFIG_SYS_SPL_MALLOC_START
2281 Starting address of the malloc pool used in SPL.
Fabio Estevam38e1a972015-11-12 12:30:19 -02002282 When this option is set the full malloc is used in SPL and
2283 it is set up by spl_init() and before that, the simple malloc()
2284 can be used if CONFIG_SYS_MALLOC_F is defined.
Tom Rini36853852012-02-14 07:29:40 +00002285
2286 CONFIG_SYS_SPL_MALLOC_SIZE
2287 The size of the malloc pool used in SPL.
Daniel Schwierzeck39ca08e2011-07-18 07:48:07 +00002288
Tom Rinic2b76002014-03-28 12:03:39 -04002289 CONFIG_SPL_OS_BOOT
2290 Enable booting directly to an OS from SPL.
2291 See also: doc/README.falcon
2292
Tom Rinife3b0c72012-08-13 11:37:56 -07002293 CONFIG_SPL_DISPLAY_PRINT
2294 For ARM, enable an optional function to print more information
2295 about the running system.
2296
Scott Wood7c810902012-09-20 16:35:21 -05002297 CONFIG_SPL_INIT_MINIMAL
2298 Arch init code should be built for a very small image
2299
Paul Kocialkowski17675c82014-11-08 23:14:56 +01002300 CONFIG_SYS_MMCSD_RAW_MODE_U_BOOT_PARTITION
2301 Partition on the MMC to load U-Boot from when the MMC is being
2302 used in raw mode
2303
Peter Korsgaard01b542f2013-05-13 08:36:29 +00002304 CONFIG_SYS_MMCSD_RAW_MODE_KERNEL_SECTOR
2305 Sector to load kernel uImage from when MMC is being
2306 used in raw mode (for Falcon mode)
2307
2308 CONFIG_SYS_MMCSD_RAW_MODE_ARGS_SECTOR,
2309 CONFIG_SYS_MMCSD_RAW_MODE_ARGS_SECTORS
2310 Sector and number of sectors to load kernel argument
2311 parameters from when MMC is being used in raw mode
2312 (for falcon mode)
2313
Paul Kocialkowski341e8cd2014-11-08 23:14:55 +01002314 CONFIG_SYS_MMCSD_FS_BOOT_PARTITION
2315 Partition on the MMC to load U-Boot from when the MMC is being
2316 used in fs mode
2317
Guillaume GARDET5065b712014-10-15 17:53:13 +02002318 CONFIG_SPL_FS_LOAD_PAYLOAD_NAME
2319 Filename to read to load U-Boot when reading from filesystem
2320
2321 CONFIG_SPL_FS_LOAD_KERNEL_NAME
Peter Korsgaard465f1f82013-05-13 08:36:27 +00002322 Filename to read to load kernel uImage when reading
Guillaume GARDET5065b712014-10-15 17:53:13 +02002323 from filesystem (for Falcon mode)
Peter Korsgaard465f1f82013-05-13 08:36:27 +00002324
Guillaume GARDET5065b712014-10-15 17:53:13 +02002325 CONFIG_SPL_FS_LOAD_ARGS_NAME
Peter Korsgaard465f1f82013-05-13 08:36:27 +00002326 Filename to read to load kernel argument parameters
Guillaume GARDET5065b712014-10-15 17:53:13 +02002327 when reading from filesystem (for Falcon mode)
Peter Korsgaard465f1f82013-05-13 08:36:27 +00002328
Scott Wood2b36fbb2012-12-06 13:33:17 +00002329 CONFIG_SPL_MPC83XX_WAIT_FOR_NAND
2330 Set this for NAND SPL on PPC mpc83xx targets, so that
2331 start.S waits for the rest of the SPL to load before
2332 continuing (the hardware starts execution after just
2333 loading the first page rather than the full 4K).
2334
Prabhakar Kushwaha6e2b9a32014-04-08 19:12:31 +05302335 CONFIG_SPL_SKIP_RELOCATE
2336 Avoid SPL relocation
2337
Scott Woodc352a0c2012-09-20 19:09:07 -05002338 CONFIG_SPL_NAND_BASE
2339 Include nand_base.c in the SPL. Requires
2340 CONFIG_SPL_NAND_DRIVERS.
2341
2342 CONFIG_SPL_NAND_DRIVERS
2343 SPL uses normal NAND drivers, not minimal drivers.
2344
Jörg Krause6f8190f2018-01-14 19:26:38 +01002345 CONFIG_SPL_NAND_IDENT
2346 SPL uses the chip ID list to identify the NAND flash.
2347 Requires CONFIG_SPL_NAND_BASE.
2348
Scott Woodc352a0c2012-09-20 19:09:07 -05002349 CONFIG_SPL_NAND_ECC
2350 Include standard software ECC in the SPL
2351
Tom Rini36853852012-02-14 07:29:40 +00002352 CONFIG_SPL_NAND_SIMPLE
Scott Wood36c440e2012-09-21 18:35:27 -05002353 Support for NAND boot using simple NAND drivers that
2354 expose the cmd_ctrl() interface.
Tom Rini36853852012-02-14 07:29:40 +00002355
Thomas Gleixner820d24d2016-07-12 20:28:12 +02002356 CONFIG_SPL_UBI
2357 Support for a lightweight UBI (fastmap) scanner and
2358 loader
2359
Heiko Schochercf000272014-10-31 08:31:00 +01002360 CONFIG_SPL_NAND_RAW_ONLY
2361 Support to boot only raw u-boot.bin images. Use this only
2362 if you need to save space.
2363
Ying Zhangdfb2b152013-08-16 15:16:12 +08002364 CONFIG_SPL_COMMON_INIT_DDR
2365 Set for common ddr init with serial presence detect in
2366 SPL binary.
2367
Tom Rini36853852012-02-14 07:29:40 +00002368 CONFIG_SYS_NAND_5_ADDR_CYCLE, CONFIG_SYS_NAND_PAGE_COUNT,
2369 CONFIG_SYS_NAND_PAGE_SIZE, CONFIG_SYS_NAND_OOBSIZE,
2370 CONFIG_SYS_NAND_BLOCK_SIZE, CONFIG_SYS_NAND_BAD_BLOCK_POS,
2371 CONFIG_SYS_NAND_ECCPOS, CONFIG_SYS_NAND_ECCSIZE,
2372 CONFIG_SYS_NAND_ECCBYTES
2373 Defines the size and behavior of the NAND that SPL uses
Scott Wood36c440e2012-09-21 18:35:27 -05002374 to read U-Boot
Tom Rini36853852012-02-14 07:29:40 +00002375
2376 CONFIG_SYS_NAND_U_BOOT_OFFS
Scott Wood36c440e2012-09-21 18:35:27 -05002377 Location in NAND to read U-Boot from
2378
2379 CONFIG_SYS_NAND_U_BOOT_DST
2380 Location in memory to load U-Boot to
2381
2382 CONFIG_SYS_NAND_U_BOOT_SIZE
2383 Size of image to load
Tom Rini36853852012-02-14 07:29:40 +00002384
2385 CONFIG_SYS_NAND_U_BOOT_START
Scott Wood36c440e2012-09-21 18:35:27 -05002386 Entry point in loaded image to jump to
Tom Rini36853852012-02-14 07:29:40 +00002387
2388 CONFIG_SYS_NAND_HW_ECC_OOBFIRST
2389 Define this if you need to first read the OOB and then the
Jeremiah Mahler03f930c2015-01-04 18:56:50 -08002390 data. This is used, for example, on davinci platforms.
Tom Rini36853852012-02-14 07:29:40 +00002391
Pavel Machekde997252012-08-30 22:42:11 +02002392 CONFIG_SPL_RAM_DEVICE
2393 Support for running image already present in ram, in SPL binary
2394
Scott Woodeb7bd972012-12-06 13:33:16 +00002395 CONFIG_SPL_PAD_TO
Benoît Thébaudeauf0180722013-04-11 09:35:49 +00002396 Image offset to which the SPL should be padded before appending
2397 the SPL payload. By default, this is defined as
2398 CONFIG_SPL_MAX_SIZE, or 0 if CONFIG_SPL_MAX_SIZE is undefined.
2399 CONFIG_SPL_PAD_TO must be either 0, meaning to append the SPL
2400 payload without any padding, or >= CONFIG_SPL_MAX_SIZE.
Scott Woodeb7bd972012-12-06 13:33:16 +00002401
Scott Woodf147eb72012-09-21 16:27:32 -05002402 CONFIG_SPL_TARGET
2403 Final target image containing SPL and payload. Some SPLs
2404 use an arch-specific makefile fragment instead, for
2405 example if more than one image needs to be produced.
2406
Marek Vasut9f2e0eb2018-05-13 00:22:52 +02002407 CONFIG_SPL_FIT_PRINT
Simon Glass82d94532013-05-08 08:05:59 +00002408 Printing information about a FIT image adds quite a bit of
2409 code to SPL. So this is normally disabled in SPL. Use this
2410 option to re-enable it. This will affect the output of the
2411 bootm command when booting a FIT image.
2412
Ying Zhang2d2e3b62013-08-16 15:16:15 +08002413- TPL framework
2414 CONFIG_TPL
2415 Enable building of TPL globally.
2416
2417 CONFIG_TPL_PAD_TO
2418 Image offset to which the TPL should be padded before appending
2419 the TPL payload. By default, this is defined as
Wolfgang Denkec7fbf52013-10-04 17:43:24 +02002420 CONFIG_SPL_MAX_SIZE, or 0 if CONFIG_SPL_MAX_SIZE is undefined.
2421 CONFIG_SPL_PAD_TO must be either 0, meaning to append the SPL
2422 payload without any padding, or >= CONFIG_SPL_MAX_SIZE.
Ying Zhang2d2e3b62013-08-16 15:16:15 +08002423
wdenkc0aa5c52003-12-06 19:49:23 +00002424- Interrupt support (PPC):
2425
wdenk1ebf41e2004-01-02 14:00:00 +00002426 There are common interrupt_init() and timer_interrupt()
2427 for all PPC archs. interrupt_init() calls interrupt_init_cpu()
Marcel Ziswilerabd8dcb2008-07-09 08:17:15 +02002428 for CPU specific initialization. interrupt_init_cpu()
wdenk1ebf41e2004-01-02 14:00:00 +00002429 should set decrementer_count to appropriate value. If
Marcel Ziswilerabd8dcb2008-07-09 08:17:15 +02002430 CPU resets decrementer automatically after interrupt
wdenk1ebf41e2004-01-02 14:00:00 +00002431 (ppc4xx) it should set decrementer_count to zero.
Marcel Ziswilerabd8dcb2008-07-09 08:17:15 +02002432 timer_interrupt() calls timer_interrupt_cpu() for CPU
wdenk1ebf41e2004-01-02 14:00:00 +00002433 specific handling. If board has watchdog / status_led
2434 / other_activity_monitor it works automatically from
2435 general timer_interrupt().
wdenkc0aa5c52003-12-06 19:49:23 +00002436
wdenkc6097192002-11-03 00:24:07 +00002437
Helmut Raigerd5a184b2011-10-20 04:19:47 +00002438Board initialization settings:
2439------------------------------
2440
2441During Initialization u-boot calls a number of board specific functions
2442to allow the preparation of board specific prerequisites, e.g. pin setup
2443before drivers are initialized. To enable these callbacks the
2444following configuration macros have to be defined. Currently this is
2445architecture specific, so please check arch/your_architecture/lib/board.c
2446typically in board_init_f() and board_init_r().
2447
2448- CONFIG_BOARD_EARLY_INIT_F: Call board_early_init_f()
2449- CONFIG_BOARD_EARLY_INIT_R: Call board_early_init_r()
2450- CONFIG_BOARD_LATE_INIT: Call board_late_init()
2451- CONFIG_BOARD_POSTCLK_INIT: Call board_postclk_init()
wdenkc6097192002-11-03 00:24:07 +00002452
wdenkc6097192002-11-03 00:24:07 +00002453Configuration Settings:
2454-----------------------
2455
York Sun6c480012014-02-26 17:03:19 -08002456- CONFIG_SYS_SUPPORT_64BIT_DATA: Defined automatically if compiled as 64-bit.
2457 Optionally it can be defined to support 64-bit memory commands.
2458
Jean-Christophe PLAGNIOL-VILLARD03836942008-10-16 15:01:15 +02002459- CONFIG_SYS_LONGHELP: Defined when you want long help messages included;
wdenkc6097192002-11-03 00:24:07 +00002460 undefine this when you're short of memory.
2461
Peter Tyserdfb72b82009-01-27 18:03:12 -06002462- CONFIG_SYS_HELP_CMD_WIDTH: Defined when you want to override the default
2463 width of the commands listed in the 'help' command output.
2464
Jean-Christophe PLAGNIOL-VILLARD03836942008-10-16 15:01:15 +02002465- CONFIG_SYS_PROMPT: This is what U-Boot prints on the console to
wdenkc6097192002-11-03 00:24:07 +00002466 prompt for user input.
2467
Jean-Christophe PLAGNIOL-VILLARD03836942008-10-16 15:01:15 +02002468- CONFIG_SYS_CBSIZE: Buffer size for input from the Console
wdenkc6097192002-11-03 00:24:07 +00002469
Jean-Christophe PLAGNIOL-VILLARD03836942008-10-16 15:01:15 +02002470- CONFIG_SYS_PBSIZE: Buffer size for Console output
wdenkc6097192002-11-03 00:24:07 +00002471
Jean-Christophe PLAGNIOL-VILLARD03836942008-10-16 15:01:15 +02002472- CONFIG_SYS_MAXARGS: max. Number of arguments accepted for monitor commands
wdenkc6097192002-11-03 00:24:07 +00002473
Jean-Christophe PLAGNIOL-VILLARD03836942008-10-16 15:01:15 +02002474- CONFIG_SYS_BARGSIZE: Buffer size for Boot Arguments which are passed to
wdenkc6097192002-11-03 00:24:07 +00002475 the application (usually a Linux kernel) when it is
2476 booted
2477
Jean-Christophe PLAGNIOL-VILLARD03836942008-10-16 15:01:15 +02002478- CONFIG_SYS_BAUDRATE_TABLE:
wdenkc6097192002-11-03 00:24:07 +00002479 List of legal baudrate settings for this board.
2480
Jean-Christophe PLAGNIOL-VILLARD03836942008-10-16 15:01:15 +02002481- CONFIG_SYS_MEMTEST_START, CONFIG_SYS_MEMTEST_END:
wdenkc6097192002-11-03 00:24:07 +00002482 Begin and End addresses of the area used by the
2483 simple memory test.
2484
Jean-Christophe PLAGNIOL-VILLARD03836942008-10-16 15:01:15 +02002485- CONFIG_SYS_MEMTEST_SCRATCH:
wdenk5958f4a2003-09-18 09:21:33 +00002486 Scratch address used by the alternate memory test
2487 You only need to set this if address zero isn't writeable
2488
York Sun5d286cd2015-12-04 11:57:07 -08002489- CONFIG_SYS_MEM_RESERVE_SECURE
York Sun1ef95cc2016-06-24 16:46:18 -07002490 Only implemented for ARMv8 for now.
York Sun5d286cd2015-12-04 11:57:07 -08002491 If defined, the size of CONFIG_SYS_MEM_RESERVE_SECURE memory
2492 is substracted from total RAM and won't be reported to OS.
2493 This memory can be used as secure memory. A variable
York Sun1ef95cc2016-06-24 16:46:18 -07002494 gd->arch.secure_ram is used to track the location. In systems
York Sun5d286cd2015-12-04 11:57:07 -08002495 the RAM base is not zero, or RAM is divided into banks,
2496 this variable needs to be recalcuated to get the address.
2497
York Sun50739372015-12-07 11:05:29 -08002498- CONFIG_SYS_MEM_TOP_HIDE:
Jean-Christophe PLAGNIOL-VILLARD03836942008-10-16 15:01:15 +02002499 If CONFIG_SYS_MEM_TOP_HIDE is defined in the board config header,
Stefan Roesea13709f2008-03-26 10:14:11 +01002500 this specified memory area will get subtracted from the top
Marcel Ziswilerabd8dcb2008-07-09 08:17:15 +02002501 (end) of RAM and won't get "touched" at all by U-Boot. By
Stefan Roesea13709f2008-03-26 10:14:11 +01002502 fixing up gd->ram_size the Linux kernel should gets passed
2503 the now "corrected" memory size and won't touch it either.
2504 This should work for arch/ppc and arch/powerpc. Only Linux
Stefan Roese37f31bf2008-03-28 11:02:53 +01002505 board ports in arch/powerpc with bootwrapper support that
Stefan Roesea13709f2008-03-26 10:14:11 +01002506 recalculate the memory size from the SDRAM controller setup
Stefan Roese37f31bf2008-03-28 11:02:53 +01002507 will have to get fixed in Linux additionally.
Stefan Roesea13709f2008-03-26 10:14:11 +01002508
2509 This option can be used as a workaround for the 440EPx/GRx
2510 CHIP 11 errata where the last 256 bytes in SDRAM shouldn't
2511 be touched.
2512
2513 WARNING: Please make sure that this value is a multiple of
2514 the Linux page size (normally 4k). If this is not the case,
2515 then the end address of the Linux memory will be located at a
2516 non page size aligned address and this could cause major
2517 problems.
2518
Jean-Christophe PLAGNIOL-VILLARD03836942008-10-16 15:01:15 +02002519- CONFIG_SYS_LOADS_BAUD_CHANGE:
wdenkc6097192002-11-03 00:24:07 +00002520 Enable temporary baudrate change while serial download
2521
Jean-Christophe PLAGNIOL-VILLARD03836942008-10-16 15:01:15 +02002522- CONFIG_SYS_SDRAM_BASE:
wdenkc6097192002-11-03 00:24:07 +00002523 Physical start address of SDRAM. _Must_ be 0 here.
2524
Jean-Christophe PLAGNIOL-VILLARD03836942008-10-16 15:01:15 +02002525- CONFIG_SYS_FLASH_BASE:
wdenkc6097192002-11-03 00:24:07 +00002526 Physical start address of Flash memory.
2527
Jean-Christophe PLAGNIOL-VILLARD03836942008-10-16 15:01:15 +02002528- CONFIG_SYS_MONITOR_BASE:
wdenkc6097192002-11-03 00:24:07 +00002529 Physical start address of boot monitor code (set by
2530 make config files to be same as the text base address
Wolfgang Denk0708bc62010-10-07 21:51:12 +02002531 (CONFIG_SYS_TEXT_BASE) used when linking) - same as
Jean-Christophe PLAGNIOL-VILLARD03836942008-10-16 15:01:15 +02002532 CONFIG_SYS_FLASH_BASE when booting from flash.
wdenkc6097192002-11-03 00:24:07 +00002533
Jean-Christophe PLAGNIOL-VILLARD03836942008-10-16 15:01:15 +02002534- CONFIG_SYS_MONITOR_LEN:
wdenk57b2d802003-06-27 21:31:46 +00002535 Size of memory reserved for monitor code, used to
2536 determine _at_compile_time_ (!) if the environment is
2537 embedded within the U-Boot image, or in a separate
2538 flash sector.
wdenkc6097192002-11-03 00:24:07 +00002539
Jean-Christophe PLAGNIOL-VILLARD03836942008-10-16 15:01:15 +02002540- CONFIG_SYS_MALLOC_LEN:
wdenkc6097192002-11-03 00:24:07 +00002541 Size of DRAM reserved for malloc() use.
2542
Simon Glass863e4042014-07-10 22:23:28 -06002543- CONFIG_SYS_MALLOC_F_LEN
2544 Size of the malloc() pool for use before relocation. If
2545 this is defined, then a very simple malloc() implementation
2546 will become available before relocation. The address is just
2547 below the global data, and the stack is moved down to make
2548 space.
2549
2550 This feature allocates regions with increasing addresses
2551 within the region. calloc() is supported, but realloc()
2552 is not available. free() is supported but does nothing.
Jeremiah Mahler03f930c2015-01-04 18:56:50 -08002553 The memory will be freed (or in fact just forgotten) when
Simon Glass863e4042014-07-10 22:23:28 -06002554 U-Boot relocates itself.
2555
Simon Glass9fa901b2014-11-10 17:16:54 -07002556- CONFIG_SYS_MALLOC_SIMPLE
2557 Provides a simple and small malloc() and calloc() for those
2558 boards which do not use the full malloc in SPL (which is
2559 enabled with CONFIG_SYS_SPL_MALLOC_START).
2560
Thierry Redingc97d9742014-12-09 22:25:22 -07002561- CONFIG_SYS_NONCACHED_MEMORY:
2562 Size of non-cached memory area. This area of memory will be
2563 typically located right below the malloc() area and mapped
2564 uncached in the MMU. This is useful for drivers that would
2565 otherwise require a lot of explicit cache maintenance. For
2566 some drivers it's also impossible to properly maintain the
2567 cache. For example if the regions that need to be flushed
2568 are not a multiple of the cache-line size, *and* padding
2569 cannot be allocated between the regions to align them (i.e.
2570 if the HW requires a contiguous array of regions, and the
2571 size of each region is not cache-aligned), then a flush of
2572 one region may result in overwriting data that hardware has
2573 written to another region in the same cache-line. This can
2574 happen for example in network drivers where descriptors for
2575 buffers are typically smaller than the CPU cache-line (e.g.
2576 16 bytes vs. 32 or 64 bytes).
2577
2578 Non-cached memory is only supported on 32-bit ARM at present.
2579
Jean-Christophe PLAGNIOL-VILLARD03836942008-10-16 15:01:15 +02002580- CONFIG_SYS_BOOTM_LEN:
Stefan Roese5d5ce292006-03-13 11:16:36 +01002581 Normally compressed uImages are limited to an
2582 uncompressed size of 8 MBytes. If this is not enough,
Jean-Christophe PLAGNIOL-VILLARD03836942008-10-16 15:01:15 +02002583 you can define CONFIG_SYS_BOOTM_LEN in your board config file
Stefan Roese5d5ce292006-03-13 11:16:36 +01002584 to adjust this setting to your needs.
2585
Jean-Christophe PLAGNIOL-VILLARD03836942008-10-16 15:01:15 +02002586- CONFIG_SYS_BOOTMAPSZ:
wdenkc6097192002-11-03 00:24:07 +00002587 Maximum size of memory mapped by the startup code of
2588 the Linux kernel; all data that must be processed by
Bartlomiej Siekac5648c82008-04-14 15:44:16 +02002589 the Linux kernel (bd_info, boot arguments, FDT blob if
2590 used) must be put below this limit, unless "bootm_low"
Robert P. J. Day832d36e2013-09-16 07:15:45 -04002591 environment variable is defined and non-zero. In such case
Bartlomiej Siekac5648c82008-04-14 15:44:16 +02002592 all data for the Linux kernel must be between "bootm_low"
Wolfgang Denk092ae952011-10-26 10:21:21 +00002593 and "bootm_low" + CONFIG_SYS_BOOTMAPSZ. The environment
Grant Likely26396382011-03-28 09:58:43 +00002594 variable "bootm_mapsize" will override the value of
2595 CONFIG_SYS_BOOTMAPSZ. If CONFIG_SYS_BOOTMAPSZ is undefined,
2596 then the value in "bootm_size" will be used instead.
wdenkc6097192002-11-03 00:24:07 +00002597
John Rigbyeea8e692010-10-13 13:57:35 -06002598- CONFIG_SYS_BOOT_RAMDISK_HIGH:
2599 Enable initrd_high functionality. If defined then the
2600 initrd_high feature is enabled and the bootm ramdisk subcommand
2601 is enabled.
2602
2603- CONFIG_SYS_BOOT_GET_CMDLINE:
2604 Enables allocating and saving kernel cmdline in space between
2605 "bootm_low" and "bootm_low" + BOOTMAPSZ.
2606
2607- CONFIG_SYS_BOOT_GET_KBD:
2608 Enables allocating and saving a kernel copy of the bd_info in
2609 space between "bootm_low" and "bootm_low" + BOOTMAPSZ.
2610
Jean-Christophe PLAGNIOL-VILLARD03836942008-10-16 15:01:15 +02002611- CONFIG_SYS_MAX_FLASH_BANKS:
wdenkc6097192002-11-03 00:24:07 +00002612 Max number of Flash memory banks
2613
Jean-Christophe PLAGNIOL-VILLARD03836942008-10-16 15:01:15 +02002614- CONFIG_SYS_MAX_FLASH_SECT:
wdenkc6097192002-11-03 00:24:07 +00002615 Max number of sectors on a Flash chip
2616
Jean-Christophe PLAGNIOL-VILLARD03836942008-10-16 15:01:15 +02002617- CONFIG_SYS_FLASH_ERASE_TOUT:
wdenkc6097192002-11-03 00:24:07 +00002618 Timeout for Flash erase operations (in ms)
2619
Jean-Christophe PLAGNIOL-VILLARD03836942008-10-16 15:01:15 +02002620- CONFIG_SYS_FLASH_WRITE_TOUT:
wdenkc6097192002-11-03 00:24:07 +00002621 Timeout for Flash write operations (in ms)
2622
Jean-Christophe PLAGNIOL-VILLARD03836942008-10-16 15:01:15 +02002623- CONFIG_SYS_FLASH_LOCK_TOUT
wdenkdccbda02003-07-14 22:13:32 +00002624 Timeout for Flash set sector lock bit operation (in ms)
2625
Jean-Christophe PLAGNIOL-VILLARD03836942008-10-16 15:01:15 +02002626- CONFIG_SYS_FLASH_UNLOCK_TOUT
wdenkdccbda02003-07-14 22:13:32 +00002627 Timeout for Flash clear lock bits operation (in ms)
2628
Jean-Christophe PLAGNIOL-VILLARD03836942008-10-16 15:01:15 +02002629- CONFIG_SYS_FLASH_PROTECTION
wdenkdccbda02003-07-14 22:13:32 +00002630 If defined, hardware flash sectors protection is used
2631 instead of U-Boot software protection.
2632
Jean-Christophe PLAGNIOL-VILLARD03836942008-10-16 15:01:15 +02002633- CONFIG_SYS_DIRECT_FLASH_TFTP:
wdenkc6097192002-11-03 00:24:07 +00002634
2635 Enable TFTP transfers directly to flash memory;
2636 without this option such a download has to be
2637 performed in two steps: (1) download to RAM, and (2)
2638 copy from RAM to flash.
2639
2640 The two-step approach is usually more reliable, since
2641 you can check if the download worked before you erase
Marcel Ziswilerabd8dcb2008-07-09 08:17:15 +02002642 the flash, but in some situations (when system RAM is
2643 too limited to allow for a temporary copy of the
wdenkc6097192002-11-03 00:24:07 +00002644 downloaded image) this option may be very useful.
2645
Jean-Christophe PLAGNIOL-VILLARD03836942008-10-16 15:01:15 +02002646- CONFIG_SYS_FLASH_CFI:
wdenk4a5c8a72003-03-06 00:02:04 +00002647 Define if the flash driver uses extra elements in the
wdenk2cefd152004-02-08 22:55:38 +00002648 common flash structure for storing flash geometry.
2649
Jean-Christophe PLAGNIOL-VILLARD8d94c232008-08-13 01:40:42 +02002650- CONFIG_FLASH_CFI_DRIVER
wdenk2cefd152004-02-08 22:55:38 +00002651 This option also enables the building of the cfi_flash driver
2652 in the drivers directory
wdenkc6097192002-11-03 00:24:07 +00002653
Piotr Ziecik3e939e92008-11-17 15:57:58 +01002654- CONFIG_FLASH_CFI_MTD
2655 This option enables the building of the cfi_mtd driver
2656 in the drivers directory. The driver exports CFI flash
2657 to the MTD layer.
2658
Jean-Christophe PLAGNIOL-VILLARD03836942008-10-16 15:01:15 +02002659- CONFIG_SYS_FLASH_USE_BUFFER_WRITE
Guennadi Liakhovetski183284f2008-04-03 13:36:02 +02002660 Use buffered writes to flash.
2661
2662- CONFIG_FLASH_SPANSION_S29WS_N
2663 s29ws-n MirrorBit flash has non-standard addresses for buffered
2664 write commands.
2665
Jean-Christophe PLAGNIOL-VILLARD03836942008-10-16 15:01:15 +02002666- CONFIG_SYS_FLASH_QUIET_TEST
Stefan Roesec443fe92005-11-22 13:20:42 +01002667 If this option is defined, the common CFI flash doesn't
2668 print it's warning upon not recognized FLASH banks. This
2669 is useful, if some of the configured banks are only
2670 optionally available.
2671
Jerry Van Barenaae73572008-03-08 13:48:01 -05002672- CONFIG_FLASH_SHOW_PROGRESS
2673 If defined (must be an integer), print out countdown
2674 digits and dots. Recommended value: 45 (9..1) for 80
2675 column displays, 15 (3..1) for 40 column displays.
2676
Stefan Roesed20cba52013-04-04 15:53:14 +02002677- CONFIG_FLASH_VERIFY
2678 If defined, the content of the flash (destination) is compared
2679 against the source after the write operation. An error message
2680 will be printed when the contents are not identical.
2681 Please note that this option is useless in nearly all cases,
2682 since such flash programming errors usually are detected earlier
2683 while unprotecting/erasing/programming. Please only enable
2684 this option if you really know what you are doing.
2685
Jean-Christophe PLAGNIOL-VILLARD03836942008-10-16 15:01:15 +02002686- CONFIG_SYS_RX_ETH_BUFFER:
Marcel Ziswilerabd8dcb2008-07-09 08:17:15 +02002687 Defines the number of Ethernet receive buffers. On some
2688 Ethernet controllers it is recommended to set this value
stroese94ef1cf2003-06-05 15:39:44 +00002689 to 8 or even higher (EEPRO100 or 405 EMAC), since all
2690 buffers can be full shortly after enabling the interface
Marcel Ziswilerabd8dcb2008-07-09 08:17:15 +02002691 on high Ethernet traffic.
stroese94ef1cf2003-06-05 15:39:44 +00002692 Defaults to 4 if not defined.
2693
Wolfgang Denk460a9ff2010-06-20 23:33:59 +02002694- CONFIG_ENV_MAX_ENTRIES
2695
Wolfgang Denk1136f692010-10-27 22:48:30 +02002696 Maximum number of entries in the hash table that is used
2697 internally to store the environment settings. The default
2698 setting is supposed to be generous and should work in most
2699 cases. This setting can be used to tune behaviour; see
2700 lib/hashtable.c for details.
Wolfgang Denk460a9ff2010-06-20 23:33:59 +02002701
Joe Hershberger71497d02012-12-11 22:16:31 -06002702- CONFIG_ENV_FLAGS_LIST_DEFAULT
2703- CONFIG_ENV_FLAGS_LIST_STATIC
Robert P. J. Day832d36e2013-09-16 07:15:45 -04002704 Enable validation of the values given to environment variables when
Joe Hershberger71497d02012-12-11 22:16:31 -06002705 calling env set. Variables can be restricted to only decimal,
2706 hexadecimal, or boolean. If CONFIG_CMD_NET is also defined,
2707 the variables can also be restricted to IP address or MAC address.
2708
2709 The format of the list is:
2710 type_attribute = [s|d|x|b|i|m]
Jeremiah Mahler03f930c2015-01-04 18:56:50 -08002711 access_attribute = [a|r|o|c]
2712 attributes = type_attribute[access_attribute]
Joe Hershberger71497d02012-12-11 22:16:31 -06002713 entry = variable_name[:attributes]
2714 list = entry[,list]
2715
2716 The type attributes are:
2717 s - String (default)
2718 d - Decimal
2719 x - Hexadecimal
2720 b - Boolean ([1yYtT|0nNfF])
2721 i - IP address
2722 m - MAC address
2723
Joe Hershberger6fe26c92012-12-11 22:16:34 -06002724 The access attributes are:
2725 a - Any (default)
2726 r - Read-only
2727 o - Write-once
2728 c - Change-default
2729
Joe Hershberger71497d02012-12-11 22:16:31 -06002730 - CONFIG_ENV_FLAGS_LIST_DEFAULT
2731 Define this to a list (string) to define the ".flags"
Jeremiah Mahler03f930c2015-01-04 18:56:50 -08002732 environment variable in the default or embedded environment.
Joe Hershberger71497d02012-12-11 22:16:31 -06002733
2734 - CONFIG_ENV_FLAGS_LIST_STATIC
2735 Define this to a list (string) to define validation that
2736 should be done if an entry is not found in the ".flags"
2737 environment variable. To override a setting in the static
2738 list, simply add an entry for the same variable name to the
2739 ".flags" variable.
2740
Joe Hershberger6db9fd42015-05-20 14:27:20 -05002741 If CONFIG_REGEX is defined, the variable_name above is evaluated as a
2742 regular expression. This allows multiple variables to define the same
2743 flags without explicitly listing them for each variable.
2744
Joe Hershberger6fe26c92012-12-11 22:16:34 -06002745- CONFIG_ENV_ACCESS_IGNORE_FORCE
2746 If defined, don't allow the -f switch to env set override variable
2747 access flags.
2748
wdenkc6097192002-11-03 00:24:07 +00002749The following definitions that deal with the placement and management
2750of environment data (variable area); in general, we support the
2751following configurations:
2752
Mike Frysinger63b8f122011-07-08 10:44:25 +00002753- CONFIG_BUILD_ENVCRC:
2754
2755 Builds up envcrc with the target environment so that external utils
2756 may easily extract it and embed it in final U-Boot images.
2757
wdenkc6097192002-11-03 00:24:07 +00002758BE CAREFUL! The first access to the environment happens quite early
Jeremiah Mahler03f930c2015-01-04 18:56:50 -08002759in U-Boot initialization (when we try to get the setting of for the
Marcel Ziswilerabd8dcb2008-07-09 08:17:15 +02002760console baudrate). You *MUST* have mapped your NVRAM area then, or
wdenkc6097192002-11-03 00:24:07 +00002761U-Boot will hang.
2762
2763Please note that even with NVRAM we still use a copy of the
2764environment in RAM: we could work on NVRAM directly, but we want to
2765keep settings there always unmodified except somebody uses "saveenv"
2766to save the current settings.
2767
Liu Gang85bcd732012-03-08 00:33:20 +00002768BE CAREFUL! For some special cases, the local device can not use
2769"saveenv" command. For example, the local device will get the
Liu Gang357bf5a2012-08-09 05:10:01 +00002770environment stored in a remote NOR flash by SRIO or PCIE link,
2771but it can not erase, write this NOR flash by SRIO or PCIE interface.
Liu Gang85bcd732012-03-08 00:33:20 +00002772
Guennadi Liakhovetskifad24442009-05-18 16:07:22 +02002773- CONFIG_NAND_ENV_DST
2774
2775 Defines address in RAM to which the nand_spl code should copy the
2776 environment. If redundant environment is used, it will be copied to
2777 CONFIG_NAND_ENV_DST + CONFIG_ENV_SIZE.
2778
Bruce Adleredecc942007-11-02 13:15:42 -07002779Please note that the environment is read-only until the monitor
wdenkc6097192002-11-03 00:24:07 +00002780has been relocated to RAM and a RAM copy of the environment has been
Simon Glass64b723f2017-08-03 12:22:12 -06002781created; also, when using EEPROM you will have to use env_get_f()
wdenkc6097192002-11-03 00:24:07 +00002782until then to read environment variables.
2783
wdenk8dba0502003-03-31 16:34:49 +00002784The environment is protected by a CRC32 checksum. Before the monitor
2785is relocated into RAM, as a result of a bad CRC you will be working
2786with the compiled-in default environment - *silently*!!! [This is
2787necessary, because the first environment variable we need is the
2788"baudrate" setting for the console - if we have a bad CRC, we don't
2789have any device yet where we could complain.]
wdenkc6097192002-11-03 00:24:07 +00002790
2791Note: once the monitor has been relocated, then it will complain if
2792the default environment is used; a new CRC is computed as soon as you
wdenk8dba0502003-03-31 16:34:49 +00002793use the "saveenv" command to store a valid environment.
wdenkc6097192002-11-03 00:24:07 +00002794
Jean-Christophe PLAGNIOL-VILLARD03836942008-10-16 15:01:15 +02002795- CONFIG_SYS_FAULT_ECHO_LINK_DOWN:
wdenk9c53f402003-10-15 23:53:47 +00002796 Echo the inverted Ethernet link state to the fault LED.
wdenk49c3f672003-10-08 22:33:00 +00002797
Jean-Christophe PLAGNIOL-VILLARD03836942008-10-16 15:01:15 +02002798 Note: If this option is active, then CONFIG_SYS_FAULT_MII_ADDR
wdenk49c3f672003-10-08 22:33:00 +00002799 also needs to be defined.
2800
Jean-Christophe PLAGNIOL-VILLARD03836942008-10-16 15:01:15 +02002801- CONFIG_SYS_FAULT_MII_ADDR:
wdenk9c53f402003-10-15 23:53:47 +00002802 MII address of the PHY to check for the Ethernet link state.
wdenkc6097192002-11-03 00:24:07 +00002803
Ron Madriddfa028a2009-02-18 14:30:44 -08002804- CONFIG_NS16550_MIN_FUNCTIONS:
2805 Define this if you desire to only have use of the NS16550_init
2806 and NS16550_putc functions for the serial driver located at
2807 drivers/serial/ns16550.c. This option is useful for saving
2808 space for already greatly restricted images, including but not
2809 limited to NAND_SPL configurations.
2810
Simon Glass28a9e332012-11-30 13:01:18 +00002811- CONFIG_DISPLAY_BOARDINFO
2812 Display information about the board that U-Boot is running on
2813 when U-Boot starts up. The board function checkboard() is called
2814 to do this.
2815
Simon Glasse8822012012-11-30 13:01:19 +00002816- CONFIG_DISPLAY_BOARDINFO_LATE
2817 Similar to the previous option, but display this information
2818 later, once stdio is running and output goes to the LCD, if
2819 present.
2820
Sascha Silbe4b9c17c2013-08-11 16:40:43 +02002821- CONFIG_BOARD_SIZE_LIMIT:
2822 Maximum size of the U-Boot image. When defined, the
2823 build system checks that the actual size does not
2824 exceed it.
2825
wdenkc6097192002-11-03 00:24:07 +00002826Low Level (hardware related) configuration options:
wdenkc8434db2003-03-26 06:55:25 +00002827---------------------------------------------------
wdenkc6097192002-11-03 00:24:07 +00002828
Jean-Christophe PLAGNIOL-VILLARD03836942008-10-16 15:01:15 +02002829- CONFIG_SYS_CACHELINE_SIZE:
wdenkc6097192002-11-03 00:24:07 +00002830 Cache Line Size of the CPU.
2831
Timur Tabid8f341c2011-08-04 18:03:41 -05002832- CONFIG_SYS_CCSRBAR_DEFAULT:
2833 Default (power-on reset) physical address of CCSR on Freescale
2834 PowerPC SOCs.
2835
2836- CONFIG_SYS_CCSRBAR:
2837 Virtual address of CCSR. On a 32-bit build, this is typically
2838 the same value as CONFIG_SYS_CCSRBAR_DEFAULT.
2839
Timur Tabid8f341c2011-08-04 18:03:41 -05002840- CONFIG_SYS_CCSRBAR_PHYS:
2841 Physical address of CCSR. CCSR can be relocated to a new
2842 physical address, if desired. In this case, this macro should
Wolfgang Denk092ae952011-10-26 10:21:21 +00002843 be set to that address. Otherwise, it should be set to the
Timur Tabid8f341c2011-08-04 18:03:41 -05002844 same value as CONFIG_SYS_CCSRBAR_DEFAULT. For example, CCSR
2845 is typically relocated on 36-bit builds. It is recommended
2846 that this macro be defined via the _HIGH and _LOW macros:
2847
2848 #define CONFIG_SYS_CCSRBAR_PHYS ((CONFIG_SYS_CCSRBAR_PHYS_HIGH
2849 * 1ull) << 32 | CONFIG_SYS_CCSRBAR_PHYS_LOW)
2850
2851- CONFIG_SYS_CCSRBAR_PHYS_HIGH:
Wolfgang Denkd590fb12011-10-07 09:58:21 +02002852 Bits 33-36 of CONFIG_SYS_CCSRBAR_PHYS. This value is typically
2853 either 0 (32-bit build) or 0xF (36-bit build). This macro is
Timur Tabid8f341c2011-08-04 18:03:41 -05002854 used in assembly code, so it must not contain typecasts or
2855 integer size suffixes (e.g. "ULL").
2856
2857- CONFIG_SYS_CCSRBAR_PHYS_LOW:
2858 Lower 32-bits of CONFIG_SYS_CCSRBAR_PHYS. This macro is
2859 used in assembly code, so it must not contain typecasts or
2860 integer size suffixes (e.g. "ULL").
2861
2862- CONFIG_SYS_CCSR_DO_NOT_RELOCATE:
2863 If this macro is defined, then CONFIG_SYS_CCSRBAR_PHYS will be
2864 forced to a value that ensures that CCSR is not relocated.
2865
wdenk1272e232002-11-10 22:06:23 +00002866- Floppy Disk Support:
Jean-Christophe PLAGNIOL-VILLARD03836942008-10-16 15:01:15 +02002867 CONFIG_SYS_FDC_DRIVE_NUMBER
wdenk1272e232002-11-10 22:06:23 +00002868
2869 the default drive number (default value 0)
2870
Jean-Christophe PLAGNIOL-VILLARD03836942008-10-16 15:01:15 +02002871 CONFIG_SYS_ISA_IO_STRIDE
wdenk1272e232002-11-10 22:06:23 +00002872
Marcel Ziswilerabd8dcb2008-07-09 08:17:15 +02002873 defines the spacing between FDC chipset registers
wdenk1272e232002-11-10 22:06:23 +00002874 (default value 1)
2875
Jean-Christophe PLAGNIOL-VILLARD03836942008-10-16 15:01:15 +02002876 CONFIG_SYS_ISA_IO_OFFSET
wdenk1272e232002-11-10 22:06:23 +00002877
wdenk4a5c8a72003-03-06 00:02:04 +00002878 defines the offset of register from address. It
2879 depends on which part of the data bus is connected to
Marcel Ziswilerabd8dcb2008-07-09 08:17:15 +02002880 the FDC chipset. (default value 0)
wdenk1272e232002-11-10 22:06:23 +00002881
Jean-Christophe PLAGNIOL-VILLARD03836942008-10-16 15:01:15 +02002882 If CONFIG_SYS_ISA_IO_STRIDE CONFIG_SYS_ISA_IO_OFFSET and
2883 CONFIG_SYS_FDC_DRIVE_NUMBER are undefined, they take their
wdenk4a5c8a72003-03-06 00:02:04 +00002884 default value.
wdenk1272e232002-11-10 22:06:23 +00002885
Jean-Christophe PLAGNIOL-VILLARD03836942008-10-16 15:01:15 +02002886 if CONFIG_SYS_FDC_HW_INIT is defined, then the function
wdenk4a5c8a72003-03-06 00:02:04 +00002887 fdc_hw_init() is called at the beginning of the FDC
2888 setup. fdc_hw_init() must be provided by the board
Jeremiah Mahler03f930c2015-01-04 18:56:50 -08002889 source code. It is used to make hardware-dependent
wdenk4a5c8a72003-03-06 00:02:04 +00002890 initializations.
wdenk1272e232002-11-10 22:06:23 +00002891
Macpaul Lind1e49942011-04-11 20:45:32 +00002892- CONFIG_IDE_AHB:
2893 Most IDE controllers were designed to be connected with PCI
2894 interface. Only few of them were designed for AHB interface.
2895 When software is doing ATA command and data transfer to
2896 IDE devices through IDE-AHB controller, some additional
2897 registers accessing to these kind of IDE-AHB controller
Jeremiah Mahler03f930c2015-01-04 18:56:50 -08002898 is required.
Macpaul Lind1e49942011-04-11 20:45:32 +00002899
Jean-Christophe PLAGNIOL-VILLARD03836942008-10-16 15:01:15 +02002900- CONFIG_SYS_IMMR: Physical address of the Internal Memory.
wdenk07d7e6b2004-12-16 21:44:03 +00002901 DO NOT CHANGE unless you know exactly what you're
Christophe Leroy069fa832017-07-06 10:23:22 +02002902 doing! (11-4) [MPC8xx systems only]
wdenkc6097192002-11-03 00:24:07 +00002903
Jean-Christophe PLAGNIOL-VILLARD03836942008-10-16 15:01:15 +02002904- CONFIG_SYS_INIT_RAM_ADDR:
wdenkc6097192002-11-03 00:24:07 +00002905
wdenkeb20ad32003-09-05 23:19:14 +00002906 Start address of memory area that can be used for
wdenkc6097192002-11-03 00:24:07 +00002907 initial data and stack; please note that this must be
2908 writable memory that is working WITHOUT special
2909 initialization, i. e. you CANNOT use normal RAM which
2910 will become available only after programming the
2911 memory controller and running certain initialization
2912 sequences.
2913
2914 U-Boot uses the following memory types:
Christophe Leroy069fa832017-07-06 10:23:22 +02002915 - MPC8xx: IMMR (internal memory of the CPU)
wdenkc6097192002-11-03 00:24:07 +00002916
Jean-Christophe PLAGNIOL-VILLARD03836942008-10-16 15:01:15 +02002917- CONFIG_SYS_GBL_DATA_OFFSET:
wdenkc6097192002-11-03 00:24:07 +00002918
2919 Offset of the initial data structure in the memory
Jean-Christophe PLAGNIOL-VILLARD03836942008-10-16 15:01:15 +02002920 area defined by CONFIG_SYS_INIT_RAM_ADDR. Usually
2921 CONFIG_SYS_GBL_DATA_OFFSET is chosen such that the initial
wdenkc6097192002-11-03 00:24:07 +00002922 data is located at the end of the available space
Wolfgang Denk1c2e98e2010-10-26 13:32:32 +02002923 (sometimes written as (CONFIG_SYS_INIT_RAM_SIZE -
Simon Glass9a6ac8b2016-10-02 18:01:06 -06002924 GENERATED_GBL_DATA_SIZE), and the initial stack is just
Jean-Christophe PLAGNIOL-VILLARD03836942008-10-16 15:01:15 +02002925 below that area (growing from (CONFIG_SYS_INIT_RAM_ADDR +
2926 CONFIG_SYS_GBL_DATA_OFFSET) downward.
wdenkc6097192002-11-03 00:24:07 +00002927
2928 Note:
2929 On the MPC824X (or other systems that use the data
2930 cache for initial memory) the address chosen for
Jean-Christophe PLAGNIOL-VILLARD03836942008-10-16 15:01:15 +02002931 CONFIG_SYS_INIT_RAM_ADDR is basically arbitrary - it must
wdenkc6097192002-11-03 00:24:07 +00002932 point to an otherwise UNUSED address space between
2933 the top of RAM and the start of the PCI space.
2934
Jean-Christophe PLAGNIOL-VILLARD03836942008-10-16 15:01:15 +02002935- CONFIG_SYS_SCCR: System Clock and reset Control Register (15-27)
wdenkc6097192002-11-03 00:24:07 +00002936
Jean-Christophe PLAGNIOL-VILLARD03836942008-10-16 15:01:15 +02002937- CONFIG_SYS_OR_TIMING_SDRAM:
wdenkc6097192002-11-03 00:24:07 +00002938 SDRAM timing
2939
Jean-Christophe PLAGNIOL-VILLARD03836942008-10-16 15:01:15 +02002940- CONFIG_SYS_MAMR_PTA:
wdenkc6097192002-11-03 00:24:07 +00002941 periodic timer for refresh
2942
Jean-Christophe PLAGNIOL-VILLARD03836942008-10-16 15:01:15 +02002943- FLASH_BASE0_PRELIM, FLASH_BASE1_PRELIM, CONFIG_SYS_REMAP_OR_AM,
2944 CONFIG_SYS_PRELIM_OR_AM, CONFIG_SYS_OR_TIMING_FLASH, CONFIG_SYS_OR0_REMAP,
2945 CONFIG_SYS_OR0_PRELIM, CONFIG_SYS_BR0_PRELIM, CONFIG_SYS_OR1_REMAP, CONFIG_SYS_OR1_PRELIM,
2946 CONFIG_SYS_BR1_PRELIM:
wdenkc6097192002-11-03 00:24:07 +00002947 Memory Controller Definitions: BR0/1 and OR0/1 (FLASH)
2948
2949- SDRAM_BASE2_PRELIM, SDRAM_BASE3_PRELIM, SDRAM_MAX_SIZE,
Jean-Christophe PLAGNIOL-VILLARD03836942008-10-16 15:01:15 +02002950 CONFIG_SYS_OR_TIMING_SDRAM, CONFIG_SYS_OR2_PRELIM, CONFIG_SYS_BR2_PRELIM,
2951 CONFIG_SYS_OR3_PRELIM, CONFIG_SYS_BR3_PRELIM:
wdenkc6097192002-11-03 00:24:07 +00002952 Memory Controller Definitions: BR2/3 and OR2/3 (SDRAM)
2953
Andrew Sharp61d47ca2012-08-29 14:16:32 +00002954- CONFIG_PCI_ENUM_ONLY
Jeremiah Mahler03f930c2015-01-04 18:56:50 -08002955 Only scan through and get the devices on the buses.
Andrew Sharp61d47ca2012-08-29 14:16:32 +00002956 Don't do any setup work, presumably because someone or
2957 something has already done it, and we don't need to do it
2958 a second time. Useful for platforms that are pre-booted
2959 by coreboot or similar.
2960
Gabor Juhosb4458732013-05-30 07:06:12 +00002961- CONFIG_PCI_INDIRECT_BRIDGE:
2962 Enable support for indirect PCI bridges.
2963
Kumar Gala8975d7a2010-12-30 12:09:53 -06002964- CONFIG_SYS_SRIO:
2965 Chip has SRIO or not
2966
2967- CONFIG_SRIO1:
2968 Board has SRIO 1 port available
2969
2970- CONFIG_SRIO2:
2971 Board has SRIO 2 port available
2972
Liu Gang27afb9c2013-05-07 16:30:46 +08002973- CONFIG_SRIO_PCIE_BOOT_MASTER
2974 Board can support master function for Boot from SRIO and PCIE
2975
Kumar Gala8975d7a2010-12-30 12:09:53 -06002976- CONFIG_SYS_SRIOn_MEM_VIRT:
2977 Virtual Address of SRIO port 'n' memory region
2978
2979- CONFIG_SYS_SRIOn_MEM_PHYS:
2980 Physical Address of SRIO port 'n' memory region
2981
2982- CONFIG_SYS_SRIOn_MEM_SIZE:
2983 Size of SRIO port 'n' memory region
2984
Fabio Estevamf17e8782013-04-11 09:35:34 +00002985- CONFIG_SYS_NAND_BUSWIDTH_16BIT
2986 Defined to tell the NAND controller that the NAND chip is using
2987 a 16 bit bus.
2988 Not all NAND drivers use this symbol.
Fabio Estevam417052b2013-04-11 09:35:35 +00002989 Example of drivers that use it:
Miquel Raynal1f1ae152018-08-16 17:30:07 +02002990 - drivers/mtd/nand/raw/ndfc.c
2991 - drivers/mtd/nand/raw/mxc_nand.c
Alex Watermancd6aae32011-05-19 15:08:36 -04002992
2993- CONFIG_SYS_NDFC_EBC0_CFG
2994 Sets the EBC0_CFG register for the NDFC. If not defined
2995 a default value will be used.
2996
Ben Warren45657152006-09-07 16:50:54 -04002997- CONFIG_SPD_EEPROM
Wolfgang Denkb240aef2008-03-26 10:40:12 +01002998 Get DDR timing information from an I2C EEPROM. Common
2999 with pluggable memory modules such as SODIMMs
3000
Ben Warren45657152006-09-07 16:50:54 -04003001 SPD_EEPROM_ADDRESS
3002 I2C address of the SPD EEPROM
3003
Jean-Christophe PLAGNIOL-VILLARD03836942008-10-16 15:01:15 +02003004- CONFIG_SYS_SPD_BUS_NUM
Wolfgang Denkb240aef2008-03-26 10:40:12 +01003005 If SPD EEPROM is on an I2C bus other than the first
3006 one, specify here. Note that the value must resolve
3007 to something your driver can deal with.
Ben Warren45657152006-09-07 16:50:54 -04003008
York Sune73cc042011-06-07 09:42:16 +08003009- CONFIG_SYS_DDR_RAW_TIMING
3010 Get DDR timing information from other than SPD. Common with
3011 soldered DDR chips onboard without SPD. DDR raw timing
3012 parameters are extracted from datasheet and hard-coded into
3013 header files or board specific files.
3014
York Sunbd495cf2011-09-16 13:21:35 -07003015- CONFIG_FSL_DDR_INTERACTIVE
3016 Enable interactive DDR debugging. See doc/README.fsl-ddr.
3017
York Sun8ced0502015-01-06 13:18:55 -08003018- CONFIG_FSL_DDR_SYNC_REFRESH
3019 Enable sync of refresh for multiple controllers.
3020
York Sunb6a35f82015-03-19 09:30:28 -07003021- CONFIG_FSL_DDR_BIST
3022 Enable built-in memory test for Freescale DDR controllers.
3023
Jean-Christophe PLAGNIOL-VILLARD03836942008-10-16 15:01:15 +02003024- CONFIG_SYS_83XX_DDR_USES_CS0
Wolfgang Denkb240aef2008-03-26 10:40:12 +01003025 Only for 83xx systems. If specified, then DDR should
3026 be configured using CS0 and CS1 instead of CS2 and CS3.
Timur Tabi054838e2006-10-31 18:44:42 -06003027
wdenk6203e402004-04-18 10:13:26 +00003028- CONFIG_RMII
3029 Enable RMII mode for all FECs.
3030 Note that this is a global option, we can't
3031 have one FEC in standard MII mode and another in RMII mode.
3032
wdenk20c98a62004-04-23 20:32:05 +00003033- CONFIG_CRC32_VERIFY
3034 Add a verify option to the crc32 command.
3035 The syntax is:
3036
3037 => crc32 -v <address> <count> <crc32>
3038
3039 Where address/count indicate a memory area
3040 and crc32 is the correct crc32 which the
3041 area should have.
3042
wdenk64519362004-07-11 17:40:54 +00003043- CONFIG_LOOPW
3044 Add the "loopw" memory command. This only takes effect if
Simon Glass92ffdee2017-08-04 16:34:27 -06003045 the memory commands are activated globally (CONFIG_CMD_MEMORY).
wdenk64519362004-07-11 17:40:54 +00003046
stroesecc3af832004-12-16 18:46:55 +00003047- CONFIG_MX_CYCLIC
3048 Add the "mdc" and "mwc" memory commands. These are cyclic
3049 "md/mw" commands.
3050 Examples:
3051
wdenk07d7e6b2004-12-16 21:44:03 +00003052 => mdc.b 10 4 500
stroesecc3af832004-12-16 18:46:55 +00003053 This command will print 4 bytes (10,11,12,13) each 500 ms.
3054
wdenk07d7e6b2004-12-16 21:44:03 +00003055 => mwc.l 100 12345678 10
stroesecc3af832004-12-16 18:46:55 +00003056 This command will write 12345678 to address 100 all 10 ms.
3057
wdenk07d7e6b2004-12-16 21:44:03 +00003058 This only takes effect if the memory commands are activated
Simon Glass92ffdee2017-08-04 16:34:27 -06003059 globally (CONFIG_CMD_MEMORY).
stroesecc3af832004-12-16 18:46:55 +00003060
wdenk3d3d99f2005-04-04 12:44:11 +00003061- CONFIG_SKIP_LOWLEVEL_INIT
Rick Chend7e6f922017-12-26 13:55:59 +08003062 [ARM, NDS32, MIPS, RISC-V only] If this variable is defined, then certain
Wolfgang Denk302141d2010-11-27 23:30:56 +01003063 low level initializations (like setting up the memory
3064 controller) are omitted and/or U-Boot does not
3065 relocate itself into RAM.
wdenk3d3d99f2005-04-04 12:44:11 +00003066
Wolfgang Denk302141d2010-11-27 23:30:56 +01003067 Normally this variable MUST NOT be defined. The only
3068 exception is when U-Boot is loaded (to RAM) by some
3069 other boot loader or by a debugger which performs
3070 these initializations itself.
wdenk3d3d99f2005-04-04 12:44:11 +00003071
Simon Glass90844072016-05-05 07:28:06 -06003072- CONFIG_SKIP_LOWLEVEL_INIT_ONLY
3073 [ARM926EJ-S only] This allows just the call to lowlevel_init()
yeongjun Kim7a203682016-07-20 22:56:12 +09003074 to be skipped. The normal CP15 init (such as enabling the
Simon Glass90844072016-05-05 07:28:06 -06003075 instruction cache) is still performed.
3076
Aneesh V552a3192011-07-13 05:11:07 +00003077- CONFIG_SPL_BUILD
Magnus Lilja1ec96d82009-06-13 20:50:00 +02003078 Modifies the behaviour of start.S when compiling a loader
3079 that is executed before the actual U-Boot. E.g. when
3080 compiling a NAND SPL.
wdenk336b2bc2005-04-02 23:52:25 +00003081
Ying Zhang2d2e3b62013-08-16 15:16:15 +08003082- CONFIG_TPL_BUILD
3083 Modifies the behaviour of start.S when compiling a loader
3084 that is executed after the SPL and before the actual U-Boot.
3085 It is loaded by the SPL.
3086
Ying Zhang0d4f5442013-05-20 14:07:23 +08003087- CONFIG_SYS_MPC85XX_NO_RESETVEC
3088 Only for 85xx systems. If this variable is specified, the section
3089 .resetvec is not kept and the section .bootpg is placed in the
3090 previous 4k of the .text section.
3091
Simon Glass17dabf02013-02-24 17:33:14 +00003092- CONFIG_ARCH_MAP_SYSMEM
3093 Generally U-Boot (and in particular the md command) uses
3094 effective address. It is therefore not necessary to regard
3095 U-Boot address as virtual addresses that need to be translated
3096 to physical addresses. However, sandbox requires this, since
3097 it maintains its own little RAM buffer which contains all
3098 addressable memory. This option causes some memory accesses
3099 to be mapped through map_sysmem() / unmap_sysmem().
3100
Simon Glassbfb59802013-02-14 04:18:54 +00003101- CONFIG_X86_RESET_VECTOR
3102 If defined, the x86 reset vector code is included. This is not
3103 needed when U-Boot is running from Coreboot.
Gabe Black14f82462012-11-27 21:08:06 +00003104
Karicheri, Muralidharanc1dc61b2014-04-04 13:16:50 -04003105- CONFIG_SYS_NAND_NO_SUBPAGE_WRITE
3106 Option to disable subpage write in NAND driver
3107 driver that uses this:
Miquel Raynal1f1ae152018-08-16 17:30:07 +02003108 drivers/mtd/nand/raw/davinci_nand.c
Karicheri, Muralidharanc1dc61b2014-04-04 13:16:50 -04003109
Timur Tabi275f4bb2011-11-22 09:21:25 -06003110Freescale QE/FMAN Firmware Support:
3111-----------------------------------
3112
3113The Freescale QUICCEngine (QE) and Frame Manager (FMAN) both support the
3114loading of "firmware", which is encoded in the QE firmware binary format.
3115This firmware often needs to be loaded during U-Boot booting, so macros
3116are used to identify the storage device (NOR flash, SPI, etc) and the address
3117within that device.
3118
Zhao Qiang83a90842014-03-21 16:21:44 +08003119- CONFIG_SYS_FMAN_FW_ADDR
3120 The address in the storage device where the FMAN microcode is located. The
Tom Rinifa911f82019-05-12 07:59:12 -04003121 meaning of this address depends on which CONFIG_SYS_QE_FMAN_FW_IN_xxx macro
Zhao Qiang83a90842014-03-21 16:21:44 +08003122 is also specified.
3123
3124- CONFIG_SYS_QE_FW_ADDR
3125 The address in the storage device where the QE microcode is located. The
Tom Rinifa911f82019-05-12 07:59:12 -04003126 meaning of this address depends on which CONFIG_SYS_QE_FMAN_FW_IN_xxx macro
Timur Tabi275f4bb2011-11-22 09:21:25 -06003127 is also specified.
3128
3129- CONFIG_SYS_QE_FMAN_FW_LENGTH
3130 The maximum possible size of the firmware. The firmware binary format
3131 has a field that specifies the actual size of the firmware, but it
3132 might not be possible to read any part of the firmware unless some
3133 local storage is allocated to hold the entire firmware first.
3134
3135- CONFIG_SYS_QE_FMAN_FW_IN_NOR
3136 Specifies that QE/FMAN firmware is located in NOR flash, mapped as
3137 normal addressable memory via the LBC. CONFIG_SYS_FMAN_FW_ADDR is the
3138 virtual address in NOR flash.
3139
3140- CONFIG_SYS_QE_FMAN_FW_IN_NAND
3141 Specifies that QE/FMAN firmware is located in NAND flash.
3142 CONFIG_SYS_FMAN_FW_ADDR is the offset within NAND flash.
3143
3144- CONFIG_SYS_QE_FMAN_FW_IN_MMC
3145 Specifies that QE/FMAN firmware is located on the primary SD/MMC
3146 device. CONFIG_SYS_FMAN_FW_ADDR is the byte offset on that device.
3147
Liu Gang1e084582012-03-08 00:33:18 +00003148- CONFIG_SYS_QE_FMAN_FW_IN_REMOTE
3149 Specifies that QE/FMAN firmware is located in the remote (master)
3150 memory space. CONFIG_SYS_FMAN_FW_ADDR is a virtual address which
Liu Gang357bf5a2012-08-09 05:10:01 +00003151 can be mapped from slave TLB->slave LAW->slave SRIO or PCIE outbound
3152 window->master inbound window->master LAW->the ucode address in
3153 master's memory space.
Timur Tabi275f4bb2011-11-22 09:21:25 -06003154
J. German Rivera8ff14b72014-06-23 15:15:55 -07003155Freescale Layerscape Management Complex Firmware Support:
3156---------------------------------------------------------
3157The Freescale Layerscape Management Complex (MC) supports the loading of
3158"firmware".
3159This firmware often needs to be loaded during U-Boot booting, so macros
3160are used to identify the storage device (NOR flash, SPI, etc) and the address
3161within that device.
3162
3163- CONFIG_FSL_MC_ENET
3164 Enable the MC driver for Layerscape SoCs.
3165
Prabhakar Kushwaha853a9012015-06-02 10:55:52 +05303166Freescale Layerscape Debug Server Support:
3167-------------------------------------------
3168The Freescale Layerscape Debug Server Support supports the loading of
3169"Debug Server firmware" and triggering SP boot-rom.
3170This firmware often needs to be loaded during U-Boot booting.
3171
York Sun928b6812015-12-07 11:08:58 -08003172- CONFIG_SYS_MC_RSV_MEM_ALIGN
3173 Define alignment of reserved memory MC requires
Prabhakar Kushwaha853a9012015-06-02 10:55:52 +05303174
Paul Kocialkowski7b917022015-07-26 18:48:15 +02003175Reproducible builds
3176-------------------
3177
3178In order to achieve reproducible builds, timestamps used in the U-Boot build
3179process have to be set to a fixed value.
3180
3181This is done using the SOURCE_DATE_EPOCH environment variable.
3182SOURCE_DATE_EPOCH is to be set on the build host's shell, not as a configuration
3183option for U-Boot or an environment variable in U-Boot.
3184
3185SOURCE_DATE_EPOCH should be set to a number of seconds since the epoch, in UTC.
3186
wdenkc6097192002-11-03 00:24:07 +00003187Building the Software:
3188======================
3189
Wolfgang Denkb240aef2008-03-26 10:40:12 +01003190Building U-Boot has been tested in several native build environments
3191and in many different cross environments. Of course we cannot support
3192all possibly existing versions of cross development tools in all
3193(potentially obsolete) versions. In case of tool chain problems we
3194recommend to use the ELDK (see http://www.denx.de/wiki/DULG/ELDK)
3195which is extensively used to build and test U-Boot.
wdenkc6097192002-11-03 00:24:07 +00003196
Wolfgang Denkb240aef2008-03-26 10:40:12 +01003197If you are not using a native environment, it is assumed that you
3198have GNU cross compiling tools available in your path. In this case,
3199you must set the environment variable CROSS_COMPILE in your shell.
3200Note that no changes to the Makefile or any other source files are
3201necessary. For example using the ELDK on a 4xx CPU, please enter:
wdenkc6097192002-11-03 00:24:07 +00003202
Wolfgang Denkb240aef2008-03-26 10:40:12 +01003203 $ CROSS_COMPILE=ppc_4xx-
3204 $ export CROSS_COMPILE
wdenkc6097192002-11-03 00:24:07 +00003205
Peter Tyserb06976d2009-03-13 18:54:51 -05003206Note: If you wish to generate Windows versions of the utilities in
3207 the tools directory you can use the MinGW toolchain
3208 (http://www.mingw.org). Set your HOST tools to the MinGW
3209 toolchain and execute 'make tools'. For example:
3210
3211 $ make HOSTCC=i586-mingw32msvc-gcc HOSTSTRIP=i586-mingw32msvc-strip tools
3212
3213 Binaries such as tools/mkimage.exe will be created which can
3214 be executed on computers running Windows.
3215
Wolfgang Denkb240aef2008-03-26 10:40:12 +01003216U-Boot is intended to be simple to build. After installing the
3217sources you must configure U-Boot for one specific board type. This
wdenkc6097192002-11-03 00:24:07 +00003218is done by typing:
3219
Holger Freyther7ba4e572014-08-04 09:26:05 +02003220 make NAME_defconfig
wdenkc6097192002-11-03 00:24:07 +00003221
Holger Freyther7ba4e572014-08-04 09:26:05 +02003222where "NAME_defconfig" is the name of one of the existing configu-
Michael Jones5a7fb6f2012-03-15 22:48:10 +00003223rations; see boards.cfg for supported names.
wdenk2f0812d2003-10-08 22:45:44 +00003224
wdenk6c59edc2004-05-03 20:45:30 +00003225Note: for some board special configuration names may exist; check if
3226 additional information is available from the board vendor; for
3227 instance, the TQM823L systems are available without (standard)
3228 or with LCD support. You can select such additional "features"
Marcel Ziswilerabd8dcb2008-07-09 08:17:15 +02003229 when choosing the configuration, i. e.
wdenkc6097192002-11-03 00:24:07 +00003230
Holger Freyther7ba4e572014-08-04 09:26:05 +02003231 make TQM823L_defconfig
wdenk6c59edc2004-05-03 20:45:30 +00003232 - will configure for a plain TQM823L, i. e. no LCD support
wdenkc6097192002-11-03 00:24:07 +00003233
Holger Freyther7ba4e572014-08-04 09:26:05 +02003234 make TQM823L_LCD_defconfig
wdenk6c59edc2004-05-03 20:45:30 +00003235 - will configure for a TQM823L with U-Boot console on LCD
wdenkc6097192002-11-03 00:24:07 +00003236
wdenk6c59edc2004-05-03 20:45:30 +00003237 etc.
wdenkc6097192002-11-03 00:24:07 +00003238
wdenkc6097192002-11-03 00:24:07 +00003239
wdenk6c59edc2004-05-03 20:45:30 +00003240Finally, type "make all", and you should get some working U-Boot
3241images ready for download to / installation on your system:
wdenkc6097192002-11-03 00:24:07 +00003242
wdenk6c59edc2004-05-03 20:45:30 +00003243- "u-boot.bin" is a raw binary image
3244- "u-boot" is an image in ELF binary format
3245- "u-boot.srec" is in Motorola S-Record format
wdenkc6097192002-11-03 00:24:07 +00003246
Marian Balakowiczefe063f2006-09-07 17:25:40 +02003247By default the build is performed locally and the objects are saved
3248in the source directory. One of the two methods can be used to change
3249this behavior and build U-Boot to some external directory:
3250
32511. Add O= to the make command line invocations:
3252
3253 make O=/tmp/build distclean
Holger Freyther7ba4e572014-08-04 09:26:05 +02003254 make O=/tmp/build NAME_defconfig
Marian Balakowiczefe063f2006-09-07 17:25:40 +02003255 make O=/tmp/build all
3256
Timo Ketolac8c67602014-11-06 14:39:05 +020032572. Set environment variable KBUILD_OUTPUT to point to the desired location:
Marian Balakowiczefe063f2006-09-07 17:25:40 +02003258
Timo Ketolac8c67602014-11-06 14:39:05 +02003259 export KBUILD_OUTPUT=/tmp/build
Marian Balakowiczefe063f2006-09-07 17:25:40 +02003260 make distclean
Holger Freyther7ba4e572014-08-04 09:26:05 +02003261 make NAME_defconfig
Marian Balakowiczefe063f2006-09-07 17:25:40 +02003262 make all
3263
Timo Ketolac8c67602014-11-06 14:39:05 +02003264Note that the command line "O=" setting overrides the KBUILD_OUTPUT environment
Marian Balakowiczefe063f2006-09-07 17:25:40 +02003265variable.
3266
Daniel Schwierzeck88484422018-01-26 16:31:04 +01003267User specific CPPFLAGS, AFLAGS and CFLAGS can be passed to the compiler by
3268setting the according environment variables KCPPFLAGS, KAFLAGS and KCFLAGS.
3269For example to treat all compiler warnings as errors:
3270
3271 make KCFLAGS=-Werror
wdenkc6097192002-11-03 00:24:07 +00003272
wdenk6c59edc2004-05-03 20:45:30 +00003273Please be aware that the Makefiles assume you are using GNU make, so
3274for instance on NetBSD you might need to use "gmake" instead of
3275native "make".
wdenkc6097192002-11-03 00:24:07 +00003276
wdenkc6097192002-11-03 00:24:07 +00003277
wdenk6c59edc2004-05-03 20:45:30 +00003278If the system board that you have is not listed, then you will need
3279to port U-Boot to your hardware platform. To do this, follow these
3280steps:
wdenkc6097192002-11-03 00:24:07 +00003281
Phil Sutterc77b4882015-12-25 14:41:18 +010032821. Create a new directory to hold your board specific code. Add any
wdenk6c59edc2004-05-03 20:45:30 +00003283 files you need. In your board directory, you will need at least
Phil Sutterc77b4882015-12-25 14:41:18 +01003284 the "Makefile" and a "<board>.c".
32852. Create a new configuration file "include/configs/<board>.h" for
3286 your board.
wdenk6c59edc2004-05-03 20:45:30 +000032873. If you're porting U-Boot to a new CPU, then also create a new
3288 directory to hold your CPU specific code. Add any files you need.
Holger Freyther7ba4e572014-08-04 09:26:05 +020032894. Run "make <board>_defconfig" with your new name.
wdenk6c59edc2004-05-03 20:45:30 +000032905. Type "make", and you should get a working "u-boot.srec" file
3291 to be installed on your target system.
32926. Debug and solve any problems that might arise.
3293 [Of course, this last step is much harder than it sounds.]
wdenkc6097192002-11-03 00:24:07 +00003294
wdenkc6097192002-11-03 00:24:07 +00003295
wdenk6c59edc2004-05-03 20:45:30 +00003296Testing of U-Boot Modifications, Ports to New Hardware, etc.:
3297==============================================================
wdenkc6097192002-11-03 00:24:07 +00003298
Wolfgang Denkb240aef2008-03-26 10:40:12 +01003299If you have modified U-Boot sources (for instance added a new board
3300or support for new devices, a new CPU, etc.) you are expected to
wdenk6c59edc2004-05-03 20:45:30 +00003301provide feedback to the other developers. The feedback normally takes
3302the form of a "patch", i. e. a context diff against a certain (latest
Wolfgang Denkb240aef2008-03-26 10:40:12 +01003303official or latest in the git repository) version of U-Boot sources.
wdenkc6097192002-11-03 00:24:07 +00003304
Wolfgang Denkb240aef2008-03-26 10:40:12 +01003305But before you submit such a patch, please verify that your modifi-
3306cation did not break existing code. At least make sure that *ALL* of
wdenk6c59edc2004-05-03 20:45:30 +00003307the supported boards compile WITHOUT ANY compiler warnings. To do so,
Simon Glassdc27def2016-07-27 20:33:08 -06003308just run the buildman script (tools/buildman/buildman), which will
3309configure and build U-Boot for ALL supported system. Be warned, this
3310will take a while. Please see the buildman README, or run 'buildman -H'
3311for documentation.
wdenkc6097192002-11-03 00:24:07 +00003312
Marian Balakowiczefe063f2006-09-07 17:25:40 +02003313
wdenk6c59edc2004-05-03 20:45:30 +00003314See also "U-Boot Porting Guide" below.
wdenkc6097192002-11-03 00:24:07 +00003315
wdenkc6097192002-11-03 00:24:07 +00003316
wdenk6c59edc2004-05-03 20:45:30 +00003317Monitor Commands - Overview:
3318============================
wdenkc6097192002-11-03 00:24:07 +00003319
wdenk6c59edc2004-05-03 20:45:30 +00003320go - start application at address 'addr'
3321run - run commands in an environment variable
3322bootm - boot application image from memory
3323bootp - boot image via network using BootP/TFTP protocol
Marek Vasutcf41a9b2012-03-14 21:52:45 +00003324bootz - boot zImage from memory
wdenk6c59edc2004-05-03 20:45:30 +00003325tftpboot- boot image via network using TFTP protocol
3326 and env variables "ipaddr" and "serverip"
3327 (and eventually "gatewayip")
Simon Glass6a398d22011-10-24 18:00:07 +00003328tftpput - upload a file via network using TFTP protocol
wdenk6c59edc2004-05-03 20:45:30 +00003329rarpboot- boot image via network using RARP/TFTP protocol
3330diskboot- boot from IDE devicebootd - boot default, i.e., run 'bootcmd'
3331loads - load S-Record file over serial line
3332loadb - load binary file over serial line (kermit mode)
3333md - memory display
3334mm - memory modify (auto-incrementing)
3335nm - memory modify (constant address)
3336mw - memory write (fill)
3337cp - memory copy
3338cmp - memory compare
3339crc32 - checksum calculation
Peter Tyser469cde42009-04-18 22:34:03 -05003340i2c - I2C sub-system
wdenk6c59edc2004-05-03 20:45:30 +00003341sspi - SPI utility commands
3342base - print or set address offset
3343printenv- print environment variables
3344setenv - set environment variables
3345saveenv - save environment variables to persistent storage
3346protect - enable or disable FLASH write protection
3347erase - erase FLASH memory
3348flinfo - print FLASH memory information
Karl O. Pinc4baf03d2012-08-03 05:57:21 +00003349nand - NAND memory operations (see doc/README.nand)
wdenk6c59edc2004-05-03 20:45:30 +00003350bdinfo - print Board Info structure
3351iminfo - print header information for application image
3352coninfo - print console devices and informations
3353ide - IDE sub-system
3354loop - infinite loop on address range
wdenk64519362004-07-11 17:40:54 +00003355loopw - infinite write loop on address range
wdenk6c59edc2004-05-03 20:45:30 +00003356mtest - simple RAM test
3357icache - enable or disable instruction cache
3358dcache - enable or disable data cache
3359reset - Perform RESET of the CPU
3360echo - echo args to console
3361version - print monitor version
3362help - print online help
3363? - alias for 'help'
wdenkc6097192002-11-03 00:24:07 +00003364
wdenkc6097192002-11-03 00:24:07 +00003365
wdenk6c59edc2004-05-03 20:45:30 +00003366Monitor Commands - Detailed Description:
3367========================================
wdenkc6097192002-11-03 00:24:07 +00003368
wdenk6c59edc2004-05-03 20:45:30 +00003369TODO.
wdenkc6097192002-11-03 00:24:07 +00003370
wdenk6c59edc2004-05-03 20:45:30 +00003371For now: just type "help <command>".
wdenkc6097192002-11-03 00:24:07 +00003372
3373
wdenk6c59edc2004-05-03 20:45:30 +00003374Environment Variables:
3375======================
wdenkc6097192002-11-03 00:24:07 +00003376
wdenk6c59edc2004-05-03 20:45:30 +00003377U-Boot supports user configuration using Environment Variables which
3378can be made persistent by saving to Flash memory.
wdenkc6097192002-11-03 00:24:07 +00003379
wdenk6c59edc2004-05-03 20:45:30 +00003380Environment Variables are set using "setenv", printed using
3381"printenv", and saved to Flash using "saveenv". Using "setenv"
3382without a value can be used to delete a variable from the
3383environment. As long as you don't save the environment you are
3384working with an in-memory copy. In case the Flash area containing the
3385environment is erased by accident, a default environment is provided.
wdenkc6097192002-11-03 00:24:07 +00003386
Wolfgang Denkb233bd72010-01-17 23:55:53 +01003387Some configuration options can be set using Environment Variables.
3388
3389List of environment variables (most likely not complete):
wdenkc6097192002-11-03 00:24:07 +00003390
wdenk6c59edc2004-05-03 20:45:30 +00003391 baudrate - see CONFIG_BAUDRATE
wdenkc6097192002-11-03 00:24:07 +00003392
wdenk6c59edc2004-05-03 20:45:30 +00003393 bootdelay - see CONFIG_BOOTDELAY
wdenkc6097192002-11-03 00:24:07 +00003394
wdenk6c59edc2004-05-03 20:45:30 +00003395 bootcmd - see CONFIG_BOOTCOMMAND
wdenkc6097192002-11-03 00:24:07 +00003396
wdenk6c59edc2004-05-03 20:45:30 +00003397 bootargs - Boot arguments when booting an RTOS image
wdenkc6097192002-11-03 00:24:07 +00003398
wdenk6c59edc2004-05-03 20:45:30 +00003399 bootfile - Name of the image to load with TFTP
wdenkc6097192002-11-03 00:24:07 +00003400
Bartlomiej Siekac5648c82008-04-14 15:44:16 +02003401 bootm_low - Memory range available for image processing in the bootm
3402 command can be restricted. This variable is given as
3403 a hexadecimal number and defines lowest address allowed
3404 for use by the bootm command. See also "bootm_size"
3405 environment variable. Address defined by "bootm_low" is
3406 also the base of the initial memory mapping for the Linux
Grant Likely26396382011-03-28 09:58:43 +00003407 kernel -- see the description of CONFIG_SYS_BOOTMAPSZ and
3408 bootm_mapsize.
3409
Wolfgang Denk092ae952011-10-26 10:21:21 +00003410 bootm_mapsize - Size of the initial memory mapping for the Linux kernel.
Grant Likely26396382011-03-28 09:58:43 +00003411 This variable is given as a hexadecimal number and it
3412 defines the size of the memory region starting at base
3413 address bootm_low that is accessible by the Linux kernel
3414 during early boot. If unset, CONFIG_SYS_BOOTMAPSZ is used
3415 as the default value if it is defined, and bootm_size is
3416 used otherwise.
Bartlomiej Siekac5648c82008-04-14 15:44:16 +02003417
3418 bootm_size - Memory range available for image processing in the bootm
3419 command can be restricted. This variable is given as
3420 a hexadecimal number and defines the size of the region
3421 allowed for use by the bootm command. See also "bootm_low"
3422 environment variable.
3423
Simon Glassa8cab882019-07-20 20:51:17 -06003424 bootstopkeysha256, bootdelaykey, bootstopkey - See README.autoboot
3425
Bartlomiej Siekae273e9f2008-10-01 15:26:31 +02003426 updatefile - Location of the software update file on a TFTP server, used
3427 by the automatic software update feature. Please refer to
3428 documentation in doc/README.update for more details.
3429
wdenk6c59edc2004-05-03 20:45:30 +00003430 autoload - if set to "no" (any string beginning with 'n'),
3431 "bootp" will just load perform a lookup of the
3432 configuration from the BOOTP server, but not try to
3433 load any image using TFTP
wdenkc6097192002-11-03 00:24:07 +00003434
wdenk6c59edc2004-05-03 20:45:30 +00003435 autostart - if set to "yes", an image loaded using the "bootp",
3436 "rarpboot", "tftpboot" or "diskboot" commands will
3437 be automatically started (by internally calling
3438 "bootm")
wdenkc6097192002-11-03 00:24:07 +00003439
wdenk6c59edc2004-05-03 20:45:30 +00003440 If set to "no", a standalone image passed to the
3441 "bootm" command will be copied to the load address
3442 (and eventually uncompressed), but NOT be started.
3443 This can be used to load and uncompress arbitrary
3444 data.
wdenkc6097192002-11-03 00:24:07 +00003445
David A. Longd558a4e2011-07-09 16:40:19 -04003446 fdt_high - if set this restricts the maximum address that the
3447 flattened device tree will be copied into upon boot.
Shawn Guo0ca9e982012-01-09 21:54:08 +00003448 For example, if you have a system with 1 GB memory
3449 at physical address 0x10000000, while Linux kernel
3450 only recognizes the first 704 MB as low memory, you
3451 may need to set fdt_high as 0x3C000000 to have the
3452 device tree blob be copied to the maximum address
3453 of the 704 MB low memory, so that Linux kernel can
3454 access it during the boot procedure.
3455
David A. Longd558a4e2011-07-09 16:40:19 -04003456 If this is set to the special value 0xFFFFFFFF then
3457 the fdt will not be copied at all on boot. For this
3458 to work it must reside in writable memory, have
3459 sufficient padding on the end of it for u-boot to
3460 add the information it needs into it, and the memory
3461 must be accessible by the kernel.
3462
Simon Glassdc6fa642011-10-24 19:15:34 +00003463 fdtcontroladdr- if set this is the address of the control flattened
3464 device tree used by U-Boot when CONFIG_OF_CONTROL is
3465 defined.
3466
wdenk0e2bd9c2004-06-06 21:51:03 +00003467 i2cfast - (PPC405GP|PPC405EP only)
3468 if set to 'y' configures Linux I2C driver for fast
3469 mode (400kHZ). This environment variable is used in
3470 initialization code. So, for changes to be effective
3471 it must be saved and board must be reset.
3472
wdenk6c59edc2004-05-03 20:45:30 +00003473 initrd_high - restrict positioning of initrd images:
3474 If this variable is not set, initrd images will be
3475 copied to the highest possible address in RAM; this
3476 is usually what you want since it allows for
3477 maximum initrd size. If for some reason you want to
3478 make sure that the initrd image is loaded below the
Jean-Christophe PLAGNIOL-VILLARD03836942008-10-16 15:01:15 +02003479 CONFIG_SYS_BOOTMAPSZ limit, you can set this environment
wdenk6c59edc2004-05-03 20:45:30 +00003480 variable to a value of "no" or "off" or "0".
3481 Alternatively, you can set it to a maximum upper
3482 address to use (U-Boot will still check that it
3483 does not overwrite the U-Boot stack and data).
wdenkc6097192002-11-03 00:24:07 +00003484
wdenk6c59edc2004-05-03 20:45:30 +00003485 For instance, when you have a system with 16 MB
3486 RAM, and want to reserve 4 MB from use by Linux,
3487 you can do this by adding "mem=12M" to the value of
3488 the "bootargs" variable. However, now you must make
3489 sure that the initrd image is placed in the first
3490 12 MB as well - this can be done with
wdenkc6097192002-11-03 00:24:07 +00003491
wdenk6c59edc2004-05-03 20:45:30 +00003492 setenv initrd_high 00c00000
wdenkc6097192002-11-03 00:24:07 +00003493
wdenk6c59edc2004-05-03 20:45:30 +00003494 If you set initrd_high to 0xFFFFFFFF, this is an
3495 indication to U-Boot that all addresses are legal
3496 for the Linux kernel, including addresses in flash
3497 memory. In this case U-Boot will NOT COPY the
3498 ramdisk at all. This may be useful to reduce the
3499 boot time on your system, but requires that this
3500 feature is supported by your Linux kernel.
wdenk3f9ab982003-04-12 23:38:12 +00003501
wdenk6c59edc2004-05-03 20:45:30 +00003502 ipaddr - IP address; needed for tftpboot command
wdenkc6097192002-11-03 00:24:07 +00003503
wdenk6c59edc2004-05-03 20:45:30 +00003504 loadaddr - Default load address for commands like "bootp",
3505 "rarpboot", "tftpboot", "loadb" or "diskboot"
wdenkc6097192002-11-03 00:24:07 +00003506
wdenk6c59edc2004-05-03 20:45:30 +00003507 loads_echo - see CONFIG_LOADS_ECHO
wdenkc6097192002-11-03 00:24:07 +00003508
wdenk6c59edc2004-05-03 20:45:30 +00003509 serverip - TFTP server IP address; needed for tftpboot command
wdenk6f770ed2003-05-23 23:18:21 +00003510
wdenk6c59edc2004-05-03 20:45:30 +00003511 bootretry - see CONFIG_BOOT_RETRY_TIME
wdenkc6097192002-11-03 00:24:07 +00003512
wdenk6c59edc2004-05-03 20:45:30 +00003513 bootdelaykey - see CONFIG_AUTOBOOT_DELAY_STR
wdenkc6097192002-11-03 00:24:07 +00003514
wdenk6c59edc2004-05-03 20:45:30 +00003515 bootstopkey - see CONFIG_AUTOBOOT_STOP_STR
wdenkc6097192002-11-03 00:24:07 +00003516
Mike Frysingera23230c2011-10-02 10:01:27 +00003517 ethprime - controls which interface is used first.
wdenkc6097192002-11-03 00:24:07 +00003518
Mike Frysingera23230c2011-10-02 10:01:27 +00003519 ethact - controls which interface is currently active.
3520 For example you can do the following
wdenkc6097192002-11-03 00:24:07 +00003521
Heiko Schocherc5e84052010-07-20 17:45:02 +02003522 => setenv ethact FEC
3523 => ping 192.168.0.1 # traffic sent on FEC
3524 => setenv ethact SCC
3525 => ping 10.0.0.1 # traffic sent on SCC
wdenkc6097192002-11-03 00:24:07 +00003526
Matthias Fuchs204f0ec2008-01-17 07:45:05 +01003527 ethrotate - When set to "no" U-Boot does not go through all
3528 available network interfaces.
3529 It just stays at the currently selected interface.
3530
Wolfgang Denkb233bd72010-01-17 23:55:53 +01003531 netretry - When set to "no" each network operation will
wdenk6c59edc2004-05-03 20:45:30 +00003532 either succeed or fail without retrying.
3533 When set to "once" the network operation will
3534 fail when all the available network interfaces
3535 are tried once without success.
3536 Useful on scripts which control the retry operation
3537 themselves.
wdenkc6097192002-11-03 00:24:07 +00003538
Jean-Christophe PLAGNIOL-VILLARD1948d6c2009-01-31 09:53:39 +01003539 npe_ucode - set load address for the NPE microcode
Jean-Christophe PLAGNIOL-VILLARDd2164ef2008-01-07 08:41:34 +01003540
Jeremiah Mahler03f930c2015-01-04 18:56:50 -08003541 silent_linux - If set then Linux will be told to boot silently, by
Simon Glass5db3f932013-07-16 20:10:00 -07003542 changing the console to be empty. If "yes" it will be
3543 made silent. If "no" it will not be made silent. If
3544 unset, then it will be made silent if the U-Boot console
3545 is silent.
3546
Albert ARIBAUD \(3ADEV\)83006852015-10-12 00:02:57 +02003547 tftpsrcp - If this is set, the value is used for TFTP's
Wolfgang Denke3cfce52005-09-24 22:37:32 +02003548 UDP source port.
3549
Albert ARIBAUD \(3ADEV\)83006852015-10-12 00:02:57 +02003550 tftpdstp - If this is set, the value is used for TFTP's UDP
Wolfgang Denk227b5192005-09-24 23:25:46 +02003551 destination port instead of the Well Know Port 69.
3552
Wolfgang Denkb233bd72010-01-17 23:55:53 +01003553 tftpblocksize - Block size to use for TFTP transfers; if not set,
3554 we use the TFTP server's default block size
3555
3556 tftptimeout - Retransmission timeout for TFTP packets (in milli-
3557 seconds, minimum value is 1000 = 1 second). Defines
3558 when a packet is considered to be lost so it has to
3559 be retransmitted. The default is 5000 = 5 seconds.
3560 Lowering this value may make downloads succeed
3561 faster in networks with high packet loss rates or
3562 with unreliable TFTP servers.
3563
Albert ARIBAUD \(3ADEV\)83006852015-10-12 00:02:57 +02003564 tftptimeoutcountmax - maximum count of TFTP timeouts (no
3565 unit, minimum value = 0). Defines how many timeouts
3566 can happen during a single file transfer before that
3567 transfer is aborted. The default is 10, and 0 means
3568 'no timeouts allowed'. Increasing this value may help
3569 downloads succeed with high packet loss rates, or with
3570 unreliable TFTP servers or client hardware.
3571
Wolfgang Denkb233bd72010-01-17 23:55:53 +01003572 vlan - When set to a value < 4095 the traffic over
Marcel Ziswilerabd8dcb2008-07-09 08:17:15 +02003573 Ethernet is encapsulated/received over 802.1q
wdenk6c59edc2004-05-03 20:45:30 +00003574 VLAN tagged frames.
wdenk145d2c12004-04-15 21:48:45 +00003575
Alexandre Messier15971322016-02-01 17:08:57 -05003576 bootpretryperiod - Period during which BOOTP/DHCP sends retries.
3577 Unsigned value, in milliseconds. If not set, the period will
3578 be either the default (28000), or a value based on
3579 CONFIG_NET_RETRY_COUNT, if defined. This value has
3580 precedence over the valu based on CONFIG_NET_RETRY_COUNT.
3581
Jason Hobbse3fe08e2011-08-31 05:37:28 +00003582The following image location variables contain the location of images
3583used in booting. The "Image" column gives the role of the image and is
3584not an environment variable name. The other columns are environment
3585variable names. "File Name" gives the name of the file on a TFTP
3586server, "RAM Address" gives the location in RAM the image will be
3587loaded to, and "Flash Location" gives the image's address in NOR
3588flash or offset in NAND flash.
3589
3590*Note* - these variables don't have to be defined for all boards, some
Fabio Estevambb7d4972015-04-25 18:53:10 -03003591boards currently use other variables for these purposes, and some
Jason Hobbse3fe08e2011-08-31 05:37:28 +00003592boards use these variables for other purposes.
3593
Wolfgang Denk092ae952011-10-26 10:21:21 +00003594Image File Name RAM Address Flash Location
3595----- --------- ----------- --------------
3596u-boot u-boot u-boot_addr_r u-boot_addr
3597Linux kernel bootfile kernel_addr_r kernel_addr
3598device tree blob fdtfile fdt_addr_r fdt_addr
3599ramdisk ramdiskfile ramdisk_addr_r ramdisk_addr
Jason Hobbse3fe08e2011-08-31 05:37:28 +00003600
wdenk6c59edc2004-05-03 20:45:30 +00003601The following environment variables may be used and automatically
3602updated by the network boot commands ("bootp" and "rarpboot"),
3603depending the information provided by your boot server:
wdenk145d2c12004-04-15 21:48:45 +00003604
wdenk6c59edc2004-05-03 20:45:30 +00003605 bootfile - see above
3606 dnsip - IP address of your Domain Name Server
3607 dnsip2 - IP address of your secondary Domain Name Server
3608 gatewayip - IP address of the Gateway (Router) to use
3609 hostname - Target hostname
3610 ipaddr - see above
3611 netmask - Subnet Mask
3612 rootpath - Pathname of the root filesystem on the NFS server
3613 serverip - see above
wdenk145d2c12004-04-15 21:48:45 +00003614
wdenk145d2c12004-04-15 21:48:45 +00003615
wdenk6c59edc2004-05-03 20:45:30 +00003616There are two special Environment Variables:
wdenkc6097192002-11-03 00:24:07 +00003617
wdenk6c59edc2004-05-03 20:45:30 +00003618 serial# - contains hardware identification information such
3619 as type string and/or serial number
3620 ethaddr - Ethernet address
wdenkc6097192002-11-03 00:24:07 +00003621
wdenk6c59edc2004-05-03 20:45:30 +00003622These variables can be set only once (usually during manufacturing of
3623the board). U-Boot refuses to delete or overwrite these variables
3624once they have been set once.
wdenkc6097192002-11-03 00:24:07 +00003625
3626
wdenk6c59edc2004-05-03 20:45:30 +00003627Further special Environment Variables:
wdenkc6097192002-11-03 00:24:07 +00003628
wdenk6c59edc2004-05-03 20:45:30 +00003629 ver - Contains the U-Boot version string as printed
3630 with the "version" command. This variable is
3631 readonly (see CONFIG_VERSION_VARIABLE).
wdenkc6097192002-11-03 00:24:07 +00003632
wdenkc6097192002-11-03 00:24:07 +00003633
wdenk6c59edc2004-05-03 20:45:30 +00003634Please note that changes to some configuration parameters may take
3635only effect after the next boot (yes, that's just like Windoze :-).
stroeseb9c17c52003-04-04 15:53:41 +00003636
stroeseb9c17c52003-04-04 15:53:41 +00003637
Joe Hershberger60fd3ad2012-12-11 22:16:24 -06003638Callback functions for environment variables:
3639---------------------------------------------
3640
3641For some environment variables, the behavior of u-boot needs to change
Jeremiah Mahler03f930c2015-01-04 18:56:50 -08003642when their values are changed. This functionality allows functions to
Joe Hershberger60fd3ad2012-12-11 22:16:24 -06003643be associated with arbitrary variables. On creation, overwrite, or
3644deletion, the callback will provide the opportunity for some side
3645effect to happen or for the change to be rejected.
3646
3647The callbacks are named and associated with a function using the
3648U_BOOT_ENV_CALLBACK macro in your board or driver code.
3649
3650These callbacks are associated with variables in one of two ways. The
3651static list can be added to by defining CONFIG_ENV_CALLBACK_LIST_STATIC
3652in the board configuration to a string that defines a list of
3653associations. The list must be in the following format:
3654
3655 entry = variable_name[:callback_name]
3656 list = entry[,list]
3657
3658If the callback name is not specified, then the callback is deleted.
3659Spaces are also allowed anywhere in the list.
3660
3661Callbacks can also be associated by defining the ".callbacks" variable
3662with the same list format above. Any association in ".callbacks" will
3663override any association in the static list. You can define
3664CONFIG_ENV_CALLBACK_LIST_DEFAULT to a list (string) to define the
Jeremiah Mahler03f930c2015-01-04 18:56:50 -08003665".callbacks" environment variable in the default or embedded environment.
Joe Hershberger60fd3ad2012-12-11 22:16:24 -06003666
Joe Hershberger6db9fd42015-05-20 14:27:20 -05003667If CONFIG_REGEX is defined, the variable_name above is evaluated as a
3668regular expression. This allows multiple variables to be connected to
3669the same callback without explicitly listing them all out.
3670
Heinrich Schuchardtc141fa52018-07-29 11:08:14 +02003671The signature of the callback functions is:
3672
3673 int callback(const char *name, const char *value, enum env_op op, int flags)
3674
3675* name - changed environment variable
3676* value - new value of the environment variable
3677* op - operation (create, overwrite, or delete)
3678* flags - attributes of the environment variable change, see flags H_* in
3679 include/search.h
3680
3681The return value is 0 if the variable change is accepted and 1 otherwise.
Joe Hershberger60fd3ad2012-12-11 22:16:24 -06003682
wdenk6c59edc2004-05-03 20:45:30 +00003683Command Line Parsing:
3684=====================
stroeseb9c17c52003-04-04 15:53:41 +00003685
wdenk6c59edc2004-05-03 20:45:30 +00003686There are two different command line parsers available with U-Boot:
3687the old "simple" one, and the much more powerful "hush" shell:
wdenkc6097192002-11-03 00:24:07 +00003688
wdenk6c59edc2004-05-03 20:45:30 +00003689Old, simple command line parser:
3690--------------------------------
wdenkc6097192002-11-03 00:24:07 +00003691
wdenk6c59edc2004-05-03 20:45:30 +00003692- supports environment variables (through setenv / saveenv commands)
3693- several commands on one line, separated by ';'
Wolfgang Denk86eb3b72005-11-20 21:40:11 +01003694- variable substitution using "... ${name} ..." syntax
wdenk6c59edc2004-05-03 20:45:30 +00003695- special characters ('$', ';') can be escaped by prefixing with '\',
3696 for example:
Wolfgang Denk86eb3b72005-11-20 21:40:11 +01003697 setenv bootcmd bootm \${address}
wdenk6c59edc2004-05-03 20:45:30 +00003698- You can also escape text by enclosing in single apostrophes, for example:
3699 setenv addip 'setenv bootargs $bootargs ip=$ipaddr:$serverip:$gatewayip:$netmask:$hostname::off'
wdenkc6097192002-11-03 00:24:07 +00003700
wdenk6c59edc2004-05-03 20:45:30 +00003701Hush shell:
3702-----------
wdenkf4688a22003-05-28 08:06:31 +00003703
wdenk6c59edc2004-05-03 20:45:30 +00003704- similar to Bourne shell, with control structures like
3705 if...then...else...fi, for...do...done; while...do...done,
3706 until...do...done, ...
3707- supports environment ("global") variables (through setenv / saveenv
3708 commands) and local shell variables (through standard shell syntax
3709 "name=value"); only environment variables can be used with "run"
3710 command
wdenkf4688a22003-05-28 08:06:31 +00003711
wdenk6c59edc2004-05-03 20:45:30 +00003712General rules:
3713--------------
wdenkf4688a22003-05-28 08:06:31 +00003714
wdenk6c59edc2004-05-03 20:45:30 +00003715(1) If a command line (or an environment variable executed by a "run"
3716 command) contains several commands separated by semicolon, and
3717 one of these commands fails, then the remaining commands will be
3718 executed anyway.
wdenkf4688a22003-05-28 08:06:31 +00003719
wdenk6c59edc2004-05-03 20:45:30 +00003720(2) If you execute several variables with one call to run (i. e.
Marcel Ziswilerabd8dcb2008-07-09 08:17:15 +02003721 calling run with a list of variables as arguments), any failing
wdenk6c59edc2004-05-03 20:45:30 +00003722 command will cause "run" to terminate, i. e. the remaining
3723 variables are not executed.
wdenkf4688a22003-05-28 08:06:31 +00003724
wdenk6c59edc2004-05-03 20:45:30 +00003725Note for Redundant Ethernet Interfaces:
3726=======================================
wdenkf4688a22003-05-28 08:06:31 +00003727
Marcel Ziswilerabd8dcb2008-07-09 08:17:15 +02003728Some boards come with redundant Ethernet interfaces; U-Boot supports
wdenk6c59edc2004-05-03 20:45:30 +00003729such configurations and is capable of automatic selection of a
3730"working" interface when needed. MAC assignment works as follows:
wdenkf4688a22003-05-28 08:06:31 +00003731
wdenk6c59edc2004-05-03 20:45:30 +00003732Network interfaces are numbered eth0, eth1, eth2, ... Corresponding
3733MAC addresses can be stored in the environment as "ethaddr" (=>eth0),
3734"eth1addr" (=>eth1), "eth2addr", ...
wdenkf4688a22003-05-28 08:06:31 +00003735
wdenk6c59edc2004-05-03 20:45:30 +00003736If the network interface stores some valid MAC address (for instance
3737in SROM), this is used as default address if there is NO correspon-
3738ding setting in the environment; if the corresponding environment
3739variable is set, this overrides the settings in the card; that means:
wdenkf4688a22003-05-28 08:06:31 +00003740
wdenk6c59edc2004-05-03 20:45:30 +00003741o If the SROM has a valid MAC address, and there is no address in the
3742 environment, the SROM's address is used.
wdenkc6097192002-11-03 00:24:07 +00003743
wdenk6c59edc2004-05-03 20:45:30 +00003744o If there is no valid address in the SROM, and a definition in the
3745 environment exists, then the value from the environment variable is
3746 used.
wdenkc6097192002-11-03 00:24:07 +00003747
wdenk6c59edc2004-05-03 20:45:30 +00003748o If both the SROM and the environment contain a MAC address, and
3749 both addresses are the same, this MAC address is used.
wdenkc6097192002-11-03 00:24:07 +00003750
wdenk6c59edc2004-05-03 20:45:30 +00003751o If both the SROM and the environment contain a MAC address, and the
3752 addresses differ, the value from the environment is used and a
3753 warning is printed.
wdenkc6097192002-11-03 00:24:07 +00003754
wdenk6c59edc2004-05-03 20:45:30 +00003755o If neither SROM nor the environment contain a MAC address, an error
Joe Hershberger2dc2b5d2015-05-04 14:55:13 -05003756 is raised. If CONFIG_NET_RANDOM_ETHADDR is defined, then in this case
3757 a random, locally-assigned MAC is used.
wdenkc6097192002-11-03 00:24:07 +00003758
Ben Warren6db991a2010-04-26 11:11:46 -07003759If Ethernet drivers implement the 'write_hwaddr' function, valid MAC addresses
Wolfgang Denk092ae952011-10-26 10:21:21 +00003760will be programmed into hardware as part of the initialization process. This
Ben Warren6db991a2010-04-26 11:11:46 -07003761may be skipped by setting the appropriate 'ethmacskip' environment variable.
3762The naming convention is as follows:
3763"ethmacskip" (=>eth0), "eth1macskip" (=>eth1) etc.
wdenkc6097192002-11-03 00:24:07 +00003764
wdenk6c59edc2004-05-03 20:45:30 +00003765Image Formats:
3766==============
wdenkc6097192002-11-03 00:24:07 +00003767
Marian Balakowicz18710b82008-03-12 12:13:13 +01003768U-Boot is capable of booting (and performing other auxiliary operations on)
3769images in two formats:
3770
3771New uImage format (FIT)
3772-----------------------
3773
3774Flexible and powerful format based on Flattened Image Tree -- FIT (similar
3775to Flattened Device Tree). It allows the use of images with multiple
3776components (several kernels, ramdisks, etc.), with contents protected by
3777SHA1, MD5 or CRC32. More details are found in the doc/uImage.FIT directory.
3778
3779
3780Old uImage format
3781-----------------
3782
3783Old image format is based on binary files which can be basically anything,
3784preceded by a special header; see the definitions in include/image.h for
3785details; basically, the header defines the following image properties:
wdenkc6097192002-11-03 00:24:07 +00003786
wdenk6c59edc2004-05-03 20:45:30 +00003787* Target Operating System (Provisions for OpenBSD, NetBSD, FreeBSD,
3788 4.4BSD, Linux, SVR4, Esix, Solaris, Irix, SCO, Dell, NCR, VxWorks,
Peter Tyser56b8dd12008-09-08 14:56:49 -05003789 LynxOS, pSOS, QNX, RTEMS, INTEGRITY;
3790 Currently supported: Linux, NetBSD, VxWorks, QNX, RTEMS, LynxOS,
3791 INTEGRITY).
Andy Shevchenko8cb5cdd2017-07-05 16:25:22 +03003792* Target CPU Architecture (Provisions for Alpha, ARM, Intel x86,
Macpaul Lin1cac36e2011-10-19 20:41:11 +00003793 IA64, MIPS, NDS32, Nios II, PowerPC, IBM S390, SuperH, Sparc, Sparc 64 Bit;
Andy Shevchenko8cb5cdd2017-07-05 16:25:22 +03003794 Currently supported: ARM, Intel x86, MIPS, NDS32, Nios II, PowerPC).
wdenk6c59edc2004-05-03 20:45:30 +00003795* Compression Type (uncompressed, gzip, bzip2)
3796* Load Address
3797* Entry Point
3798* Image Name
3799* Image Timestamp
wdenkc6097192002-11-03 00:24:07 +00003800
wdenk6c59edc2004-05-03 20:45:30 +00003801The header is marked by a special Magic Number, and both the header
3802and the data portions of the image are secured against corruption by
3803CRC32 checksums.
wdenkc6097192002-11-03 00:24:07 +00003804
wdenkc6097192002-11-03 00:24:07 +00003805
wdenk6c59edc2004-05-03 20:45:30 +00003806Linux Support:
3807==============
wdenkc6097192002-11-03 00:24:07 +00003808
wdenk6c59edc2004-05-03 20:45:30 +00003809Although U-Boot should support any OS or standalone application
3810easily, the main focus has always been on Linux during the design of
3811U-Boot.
wdenkc6097192002-11-03 00:24:07 +00003812
wdenk6c59edc2004-05-03 20:45:30 +00003813U-Boot includes many features that so far have been part of some
3814special "boot loader" code within the Linux kernel. Also, any
3815"initrd" images to be used are no longer part of one big Linux image;
3816instead, kernel and "initrd" are separate images. This implementation
3817serves several purposes:
wdenkc6097192002-11-03 00:24:07 +00003818
wdenk6c59edc2004-05-03 20:45:30 +00003819- the same features can be used for other OS or standalone
3820 applications (for instance: using compressed images to reduce the
3821 Flash memory footprint)
wdenkc6097192002-11-03 00:24:07 +00003822
wdenk6c59edc2004-05-03 20:45:30 +00003823- it becomes much easier to port new Linux kernel versions because
3824 lots of low-level, hardware dependent stuff are done by U-Boot
wdenkc6097192002-11-03 00:24:07 +00003825
wdenk6c59edc2004-05-03 20:45:30 +00003826- the same Linux kernel image can now be used with different "initrd"
3827 images; of course this also means that different kernel images can
3828 be run with the same "initrd". This makes testing easier (you don't
3829 have to build a new "zImage.initrd" Linux image when you just
3830 change a file in your "initrd"). Also, a field-upgrade of the
3831 software is easier now.
wdenkc6097192002-11-03 00:24:07 +00003832
wdenkc6097192002-11-03 00:24:07 +00003833
wdenk6c59edc2004-05-03 20:45:30 +00003834Linux HOWTO:
3835============
wdenkc6097192002-11-03 00:24:07 +00003836
wdenk6c59edc2004-05-03 20:45:30 +00003837Porting Linux to U-Boot based systems:
3838---------------------------------------
wdenkc6097192002-11-03 00:24:07 +00003839
wdenk6c59edc2004-05-03 20:45:30 +00003840U-Boot cannot save you from doing all the necessary modifications to
3841configure the Linux device drivers for use with your target hardware
3842(no, we don't intend to provide a full virtual machine interface to
3843Linux :-).
wdenkc6097192002-11-03 00:24:07 +00003844
Stefan Roese88fbf932010-04-15 16:07:28 +02003845But now you can ignore ALL boot loader code (in arch/powerpc/mbxboot).
wdenkc6097192002-11-03 00:24:07 +00003846
wdenk6c59edc2004-05-03 20:45:30 +00003847Just make sure your machine specific header file (for instance
3848include/asm-ppc/tqm8xx.h) includes the same definition of the Board
Markus Heidelberg47167572008-09-07 20:18:27 +02003849Information structure as we define in include/asm-<arch>/u-boot.h,
3850and make sure that your definition of IMAP_ADDR uses the same value
Jean-Christophe PLAGNIOL-VILLARD03836942008-10-16 15:01:15 +02003851as your U-Boot configuration in CONFIG_SYS_IMMR.
wdenkc6097192002-11-03 00:24:07 +00003852
Simon Glassd097e592014-06-11 23:29:46 -06003853Note that U-Boot now has a driver model, a unified model for drivers.
3854If you are adding a new driver, plumb it into driver model. If there
3855is no uclass available, you are encouraged to create one. See
3856doc/driver-model.
3857
wdenkc6097192002-11-03 00:24:07 +00003858
wdenk6c59edc2004-05-03 20:45:30 +00003859Configuring the Linux kernel:
3860-----------------------------
wdenkc6097192002-11-03 00:24:07 +00003861
wdenk6c59edc2004-05-03 20:45:30 +00003862No specific requirements for U-Boot. Make sure you have some root
3863device (initial ramdisk, NFS) for your target system.
wdenkc6097192002-11-03 00:24:07 +00003864
wdenkc6097192002-11-03 00:24:07 +00003865
wdenk6c59edc2004-05-03 20:45:30 +00003866Building a Linux Image:
3867-----------------------
wdenkc6097192002-11-03 00:24:07 +00003868
wdenk6c59edc2004-05-03 20:45:30 +00003869With U-Boot, "normal" build targets like "zImage" or "bzImage" are
3870not used. If you use recent kernel source, a new build target
3871"uImage" will exist which automatically builds an image usable by
3872U-Boot. Most older kernels also have support for a "pImage" target,
3873which was introduced for our predecessor project PPCBoot and uses a
3874100% compatible format.
wdenkc6097192002-11-03 00:24:07 +00003875
wdenk6c59edc2004-05-03 20:45:30 +00003876Example:
wdenkc6097192002-11-03 00:24:07 +00003877
Holger Freyther7ba4e572014-08-04 09:26:05 +02003878 make TQM850L_defconfig
wdenk6c59edc2004-05-03 20:45:30 +00003879 make oldconfig
3880 make dep
3881 make uImage
wdenkc6097192002-11-03 00:24:07 +00003882
wdenk6c59edc2004-05-03 20:45:30 +00003883The "uImage" build target uses a special tool (in 'tools/mkimage') to
3884encapsulate a compressed Linux kernel image with header information,
3885CRC32 checksum etc. for use with U-Boot. This is what we are doing:
wdenkc6097192002-11-03 00:24:07 +00003886
wdenk6c59edc2004-05-03 20:45:30 +00003887* build a standard "vmlinux" kernel image (in ELF binary format):
wdenkc6097192002-11-03 00:24:07 +00003888
wdenk6c59edc2004-05-03 20:45:30 +00003889* convert the kernel into a raw binary image:
wdenkc6097192002-11-03 00:24:07 +00003890
wdenk6c59edc2004-05-03 20:45:30 +00003891 ${CROSS_COMPILE}-objcopy -O binary \
3892 -R .note -R .comment \
3893 -S vmlinux linux.bin
wdenk24ee89b2002-11-03 17:56:27 +00003894
wdenk6c59edc2004-05-03 20:45:30 +00003895* compress the binary image:
wdenk24ee89b2002-11-03 17:56:27 +00003896
wdenk6c59edc2004-05-03 20:45:30 +00003897 gzip -9 linux.bin
wdenk24ee89b2002-11-03 17:56:27 +00003898
wdenk6c59edc2004-05-03 20:45:30 +00003899* package compressed binary image for U-Boot:
wdenk24ee89b2002-11-03 17:56:27 +00003900
wdenk6c59edc2004-05-03 20:45:30 +00003901 mkimage -A ppc -O linux -T kernel -C gzip \
3902 -a 0 -e 0 -n "Linux Kernel Image" \
3903 -d linux.bin.gz uImage
wdenkc6097192002-11-03 00:24:07 +00003904
wdenkc6097192002-11-03 00:24:07 +00003905
wdenk6c59edc2004-05-03 20:45:30 +00003906The "mkimage" tool can also be used to create ramdisk images for use
3907with U-Boot, either separated from the Linux kernel image, or
3908combined into one file. "mkimage" encapsulates the images with a 64
3909byte header containing information about target architecture,
3910operating system, image type, compression method, entry points, time
3911stamp, CRC32 checksums, etc.
wdenkc6097192002-11-03 00:24:07 +00003912
wdenk6c59edc2004-05-03 20:45:30 +00003913"mkimage" can be called in two ways: to verify existing images and
3914print the header information, or to build new images.
wdenk24ee89b2002-11-03 17:56:27 +00003915
wdenk6c59edc2004-05-03 20:45:30 +00003916In the first form (with "-l" option) mkimage lists the information
3917contained in the header of an existing U-Boot image; this includes
3918checksum verification:
wdenk24ee89b2002-11-03 17:56:27 +00003919
wdenk6c59edc2004-05-03 20:45:30 +00003920 tools/mkimage -l image
3921 -l ==> list image header information
wdenk24ee89b2002-11-03 17:56:27 +00003922
wdenk6c59edc2004-05-03 20:45:30 +00003923The second form (with "-d" option) is used to build a U-Boot image
3924from a "data file" which is used as image payload:
wdenk24ee89b2002-11-03 17:56:27 +00003925
wdenk6c59edc2004-05-03 20:45:30 +00003926 tools/mkimage -A arch -O os -T type -C comp -a addr -e ep \
3927 -n name -d data_file image
3928 -A ==> set architecture to 'arch'
3929 -O ==> set operating system to 'os'
3930 -T ==> set image type to 'type'
3931 -C ==> set compression type 'comp'
3932 -a ==> set load address to 'addr' (hex)
3933 -e ==> set entry point to 'ep' (hex)
3934 -n ==> set image name to 'name'
3935 -d ==> use image data from 'datafile'
wdenk24ee89b2002-11-03 17:56:27 +00003936
wdenkcd914452004-05-29 16:53:29 +00003937Right now, all Linux kernels for PowerPC systems use the same load
3938address (0x00000000), but the entry point address depends on the
3939kernel version:
wdenkc6097192002-11-03 00:24:07 +00003940
wdenk6c59edc2004-05-03 20:45:30 +00003941- 2.2.x kernels have the entry point at 0x0000000C,
3942- 2.3.x and later kernels have the entry point at 0x00000000.
wdenkc6097192002-11-03 00:24:07 +00003943
wdenk6c59edc2004-05-03 20:45:30 +00003944So a typical call to build a U-Boot image would read:
wdenkc6097192002-11-03 00:24:07 +00003945
wdenk6c59edc2004-05-03 20:45:30 +00003946 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \
3947 > -A ppc -O linux -T kernel -C gzip -a 0 -e 0 \
Stefan Roese88fbf932010-04-15 16:07:28 +02003948 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux.gz \
wdenk6c59edc2004-05-03 20:45:30 +00003949 > examples/uImage.TQM850L
3950 Image Name: 2.4.4 kernel for TQM850L
3951 Created: Wed Jul 19 02:34:59 2000
3952 Image Type: PowerPC Linux Kernel Image (gzip compressed)
3953 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB
3954 Load Address: 0x00000000
3955 Entry Point: 0x00000000
wdenkc6097192002-11-03 00:24:07 +00003956
wdenk6c59edc2004-05-03 20:45:30 +00003957To verify the contents of the image (or check for corruption):
wdenkc6097192002-11-03 00:24:07 +00003958
wdenk6c59edc2004-05-03 20:45:30 +00003959 -> tools/mkimage -l examples/uImage.TQM850L
3960 Image Name: 2.4.4 kernel for TQM850L
3961 Created: Wed Jul 19 02:34:59 2000
3962 Image Type: PowerPC Linux Kernel Image (gzip compressed)
3963 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB
3964 Load Address: 0x00000000
3965 Entry Point: 0x00000000
wdenkc6097192002-11-03 00:24:07 +00003966
wdenk6c59edc2004-05-03 20:45:30 +00003967NOTE: for embedded systems where boot time is critical you can trade
3968speed for memory and install an UNCOMPRESSED image instead: this
3969needs more space in Flash, but boots much faster since it does not
3970need to be uncompressed:
wdenkc6097192002-11-03 00:24:07 +00003971
Stefan Roese88fbf932010-04-15 16:07:28 +02003972 -> gunzip /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux.gz
wdenk6c59edc2004-05-03 20:45:30 +00003973 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \
3974 > -A ppc -O linux -T kernel -C none -a 0 -e 0 \
Stefan Roese88fbf932010-04-15 16:07:28 +02003975 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux \
wdenk6c59edc2004-05-03 20:45:30 +00003976 > examples/uImage.TQM850L-uncompressed
3977 Image Name: 2.4.4 kernel for TQM850L
3978 Created: Wed Jul 19 02:34:59 2000
3979 Image Type: PowerPC Linux Kernel Image (uncompressed)
3980 Data Size: 792160 Bytes = 773.59 kB = 0.76 MB
3981 Load Address: 0x00000000
3982 Entry Point: 0x00000000
wdenkc6097192002-11-03 00:24:07 +00003983
wdenkc6097192002-11-03 00:24:07 +00003984
wdenk6c59edc2004-05-03 20:45:30 +00003985Similar you can build U-Boot images from a 'ramdisk.image.gz' file
3986when your kernel is intended to use an initial ramdisk:
wdenkc6097192002-11-03 00:24:07 +00003987
wdenk6c59edc2004-05-03 20:45:30 +00003988 -> tools/mkimage -n 'Simple Ramdisk Image' \
3989 > -A ppc -O linux -T ramdisk -C gzip \
3990 > -d /LinuxPPC/images/SIMPLE-ramdisk.image.gz examples/simple-initrd
3991 Image Name: Simple Ramdisk Image
3992 Created: Wed Jan 12 14:01:50 2000
3993 Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
3994 Data Size: 566530 Bytes = 553.25 kB = 0.54 MB
3995 Load Address: 0x00000000
3996 Entry Point: 0x00000000
wdenkc6097192002-11-03 00:24:07 +00003997
Guilherme Maciel Ferreira51553812013-12-01 12:43:11 -07003998The "dumpimage" is a tool to disassemble images built by mkimage. Its "-i"
3999option performs the converse operation of the mkimage's second form (the "-d"
4000option). Given an image built by mkimage, the dumpimage extracts a "data file"
4001from the image:
4002
Guilherme Maciel Ferreira40bf5632015-01-15 02:54:40 -02004003 tools/dumpimage -i image -T type -p position data_file
4004 -i ==> extract from the 'image' a specific 'data_file'
4005 -T ==> set image type to 'type'
4006 -p ==> 'position' (starting at 0) of the 'data_file' inside the 'image'
Guilherme Maciel Ferreira51553812013-12-01 12:43:11 -07004007
wdenkc6097192002-11-03 00:24:07 +00004008
wdenk6c59edc2004-05-03 20:45:30 +00004009Installing a Linux Image:
4010-------------------------
wdenkc6097192002-11-03 00:24:07 +00004011
wdenk6c59edc2004-05-03 20:45:30 +00004012To downloading a U-Boot image over the serial (console) interface,
4013you must convert the image to S-Record format:
wdenkc6097192002-11-03 00:24:07 +00004014
wdenk6c59edc2004-05-03 20:45:30 +00004015 objcopy -I binary -O srec examples/image examples/image.srec
wdenkc6097192002-11-03 00:24:07 +00004016
wdenk6c59edc2004-05-03 20:45:30 +00004017The 'objcopy' does not understand the information in the U-Boot
4018image header, so the resulting S-Record file will be relative to
4019address 0x00000000. To load it to a given address, you need to
4020specify the target address as 'offset' parameter with the 'loads'
4021command.
wdenkc6097192002-11-03 00:24:07 +00004022
wdenk6c59edc2004-05-03 20:45:30 +00004023Example: install the image to address 0x40100000 (which on the
4024TQM8xxL is in the first Flash bank):
wdenkc6097192002-11-03 00:24:07 +00004025
wdenk6c59edc2004-05-03 20:45:30 +00004026 => erase 40100000 401FFFFF
wdenkc6097192002-11-03 00:24:07 +00004027
wdenk6c59edc2004-05-03 20:45:30 +00004028 .......... done
4029 Erased 8 sectors
wdenkc6097192002-11-03 00:24:07 +00004030
wdenk6c59edc2004-05-03 20:45:30 +00004031 => loads 40100000
4032 ## Ready for S-Record download ...
4033 ~>examples/image.srec
4034 1 2 3 4 5 6 7 8 9 10 11 12 13 ...
4035 ...
4036 15989 15990 15991 15992
4037 [file transfer complete]
4038 [connected]
4039 ## Start Addr = 0x00000000
wdenkc6097192002-11-03 00:24:07 +00004040
wdenkc6097192002-11-03 00:24:07 +00004041
wdenk6c59edc2004-05-03 20:45:30 +00004042You can check the success of the download using the 'iminfo' command;
Wolfgang Denkb240aef2008-03-26 10:40:12 +01004043this includes a checksum verification so you can be sure no data
wdenk6c59edc2004-05-03 20:45:30 +00004044corruption happened:
wdenkc6097192002-11-03 00:24:07 +00004045
wdenk6c59edc2004-05-03 20:45:30 +00004046 => imi 40100000
wdenkc6097192002-11-03 00:24:07 +00004047
wdenk6c59edc2004-05-03 20:45:30 +00004048 ## Checking Image at 40100000 ...
4049 Image Name: 2.2.13 for initrd on TQM850L
4050 Image Type: PowerPC Linux Kernel Image (gzip compressed)
4051 Data Size: 335725 Bytes = 327 kB = 0 MB
4052 Load Address: 00000000
4053 Entry Point: 0000000c
4054 Verifying Checksum ... OK
wdenkc6097192002-11-03 00:24:07 +00004055
4056
wdenk6c59edc2004-05-03 20:45:30 +00004057Boot Linux:
4058-----------
wdenkc6097192002-11-03 00:24:07 +00004059
wdenk6c59edc2004-05-03 20:45:30 +00004060The "bootm" command is used to boot an application that is stored in
4061memory (RAM or Flash). In case of a Linux kernel image, the contents
4062of the "bootargs" environment variable is passed to the kernel as
4063parameters. You can check and modify this variable using the
4064"printenv" and "setenv" commands:
wdenkc6097192002-11-03 00:24:07 +00004065
wdenkc6097192002-11-03 00:24:07 +00004066
wdenk6c59edc2004-05-03 20:45:30 +00004067 => printenv bootargs
4068 bootargs=root=/dev/ram
wdenkc6097192002-11-03 00:24:07 +00004069
wdenk6c59edc2004-05-03 20:45:30 +00004070 => setenv bootargs root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
wdenkc6097192002-11-03 00:24:07 +00004071
wdenk6c59edc2004-05-03 20:45:30 +00004072 => printenv bootargs
4073 bootargs=root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
wdenkc6097192002-11-03 00:24:07 +00004074
wdenk6c59edc2004-05-03 20:45:30 +00004075 => bootm 40020000
4076 ## Booting Linux kernel at 40020000 ...
4077 Image Name: 2.2.13 for NFS on TQM850L
4078 Image Type: PowerPC Linux Kernel Image (gzip compressed)
4079 Data Size: 381681 Bytes = 372 kB = 0 MB
4080 Load Address: 00000000
4081 Entry Point: 0000000c
4082 Verifying Checksum ... OK
4083 Uncompressing Kernel Image ... OK
4084 Linux version 2.2.13 (wd@denx.local.net) (gcc version 2.95.2 19991024 (release)) #1 Wed Jul 19 02:35:17 MEST 2000
4085 Boot arguments: root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
4086 time_init: decrementer frequency = 187500000/60
4087 Calibrating delay loop... 49.77 BogoMIPS
4088 Memory: 15208k available (700k kernel code, 444k data, 32k init) [c0000000,c1000000]
4089 ...
wdenkc6097192002-11-03 00:24:07 +00004090
Marcel Ziswilerabd8dcb2008-07-09 08:17:15 +02004091If you want to boot a Linux kernel with initial RAM disk, you pass
wdenk6c59edc2004-05-03 20:45:30 +00004092the memory addresses of both the kernel and the initrd image (PPBCOOT
4093format!) to the "bootm" command:
wdenkc6097192002-11-03 00:24:07 +00004094
wdenk6c59edc2004-05-03 20:45:30 +00004095 => imi 40100000 40200000
wdenkc6097192002-11-03 00:24:07 +00004096
wdenk6c59edc2004-05-03 20:45:30 +00004097 ## Checking Image at 40100000 ...
4098 Image Name: 2.2.13 for initrd on TQM850L
4099 Image Type: PowerPC Linux Kernel Image (gzip compressed)
4100 Data Size: 335725 Bytes = 327 kB = 0 MB
4101 Load Address: 00000000
4102 Entry Point: 0000000c
4103 Verifying Checksum ... OK
wdenkc6097192002-11-03 00:24:07 +00004104
wdenk6c59edc2004-05-03 20:45:30 +00004105 ## Checking Image at 40200000 ...
4106 Image Name: Simple Ramdisk Image
4107 Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
4108 Data Size: 566530 Bytes = 553 kB = 0 MB
4109 Load Address: 00000000
4110 Entry Point: 00000000
4111 Verifying Checksum ... OK
wdenkc6097192002-11-03 00:24:07 +00004112
wdenk6c59edc2004-05-03 20:45:30 +00004113 => bootm 40100000 40200000
4114 ## Booting Linux kernel at 40100000 ...
4115 Image Name: 2.2.13 for initrd on TQM850L
4116 Image Type: PowerPC Linux Kernel Image (gzip compressed)
4117 Data Size: 335725 Bytes = 327 kB = 0 MB
4118 Load Address: 00000000
4119 Entry Point: 0000000c
4120 Verifying Checksum ... OK
4121 Uncompressing Kernel Image ... OK
4122 ## Loading RAMDisk Image at 40200000 ...
4123 Image Name: Simple Ramdisk Image
4124 Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
4125 Data Size: 566530 Bytes = 553 kB = 0 MB
4126 Load Address: 00000000
4127 Entry Point: 00000000
4128 Verifying Checksum ... OK
4129 Loading Ramdisk ... OK
4130 Linux version 2.2.13 (wd@denx.local.net) (gcc version 2.95.2 19991024 (release)) #1 Wed Jul 19 02:32:08 MEST 2000
4131 Boot arguments: root=/dev/ram
4132 time_init: decrementer frequency = 187500000/60
4133 Calibrating delay loop... 49.77 BogoMIPS
4134 ...
4135 RAMDISK: Compressed image found at block 0
4136 VFS: Mounted root (ext2 filesystem).
wdenkc6097192002-11-03 00:24:07 +00004137
wdenk6c59edc2004-05-03 20:45:30 +00004138 bash#
wdenkc6097192002-11-03 00:24:07 +00004139
Matthew McClintockefae4ca2006-06-28 10:41:37 -05004140Boot Linux and pass a flat device tree:
4141-----------
4142
4143First, U-Boot must be compiled with the appropriate defines. See the section
4144titled "Linux Kernel Interface" above for a more in depth explanation. The
4145following is an example of how to start a kernel and pass an updated
4146flat device tree:
4147
4148=> print oftaddr
4149oftaddr=0x300000
4150=> print oft
4151oft=oftrees/mpc8540ads.dtb
4152=> tftp $oftaddr $oft
4153Speed: 1000, full duplex
4154Using TSEC0 device
4155TFTP from server 192.168.1.1; our IP address is 192.168.1.101
4156Filename 'oftrees/mpc8540ads.dtb'.
4157Load address: 0x300000
4158Loading: #
4159done
4160Bytes transferred = 4106 (100a hex)
4161=> tftp $loadaddr $bootfile
4162Speed: 1000, full duplex
4163Using TSEC0 device
4164TFTP from server 192.168.1.1; our IP address is 192.168.1.2
4165Filename 'uImage'.
4166Load address: 0x200000
4167Loading:############
4168done
4169Bytes transferred = 1029407 (fb51f hex)
4170=> print loadaddr
4171loadaddr=200000
4172=> print oftaddr
4173oftaddr=0x300000
4174=> bootm $loadaddr - $oftaddr
4175## Booting image at 00200000 ...
Wolfgang Denk018147d2006-11-27 15:32:42 +01004176 Image Name: Linux-2.6.17-dirty
4177 Image Type: PowerPC Linux Kernel Image (gzip compressed)
4178 Data Size: 1029343 Bytes = 1005.2 kB
Matthew McClintockefae4ca2006-06-28 10:41:37 -05004179 Load Address: 00000000
Wolfgang Denk018147d2006-11-27 15:32:42 +01004180 Entry Point: 00000000
Matthew McClintockefae4ca2006-06-28 10:41:37 -05004181 Verifying Checksum ... OK
4182 Uncompressing Kernel Image ... OK
4183Booting using flat device tree at 0x300000
4184Using MPC85xx ADS machine description
4185Memory CAM mapping: CAM0=256Mb, CAM1=256Mb, CAM2=0Mb residual: 0Mb
4186[snip]
4187
4188
wdenk6c59edc2004-05-03 20:45:30 +00004189More About U-Boot Image Types:
4190------------------------------
wdenkc6097192002-11-03 00:24:07 +00004191
wdenk6c59edc2004-05-03 20:45:30 +00004192U-Boot supports the following image types:
wdenkc6097192002-11-03 00:24:07 +00004193
wdenk6c59edc2004-05-03 20:45:30 +00004194 "Standalone Programs" are directly runnable in the environment
4195 provided by U-Boot; it is expected that (if they behave
4196 well) you can continue to work in U-Boot after return from
4197 the Standalone Program.
4198 "OS Kernel Images" are usually images of some Embedded OS which
4199 will take over control completely. Usually these programs
4200 will install their own set of exception handlers, device
4201 drivers, set up the MMU, etc. - this means, that you cannot
4202 expect to re-enter U-Boot except by resetting the CPU.
4203 "RAMDisk Images" are more or less just data blocks, and their
4204 parameters (address, size) are passed to an OS kernel that is
4205 being started.
4206 "Multi-File Images" contain several images, typically an OS
4207 (Linux) kernel image and one or more data images like
4208 RAMDisks. This construct is useful for instance when you want
4209 to boot over the network using BOOTP etc., where the boot
4210 server provides just a single image file, but you want to get
4211 for instance an OS kernel and a RAMDisk image.
wdenkc6097192002-11-03 00:24:07 +00004212
wdenk6c59edc2004-05-03 20:45:30 +00004213 "Multi-File Images" start with a list of image sizes, each
4214 image size (in bytes) specified by an "uint32_t" in network
4215 byte order. This list is terminated by an "(uint32_t)0".
4216 Immediately after the terminating 0 follow the images, one by
4217 one, all aligned on "uint32_t" boundaries (size rounded up to
4218 a multiple of 4 bytes).
wdenkc6097192002-11-03 00:24:07 +00004219
wdenk6c59edc2004-05-03 20:45:30 +00004220 "Firmware Images" are binary images containing firmware (like
4221 U-Boot or FPGA images) which usually will be programmed to
4222 flash memory.
wdenk4fc95692003-02-28 00:49:47 +00004223
wdenk6c59edc2004-05-03 20:45:30 +00004224 "Script files" are command sequences that will be executed by
4225 U-Boot's command interpreter; this feature is especially
4226 useful when you configure U-Boot to use a real shell (hush)
4227 as command interpreter.
wdenk4fc95692003-02-28 00:49:47 +00004228
Marek Vasutcf41a9b2012-03-14 21:52:45 +00004229Booting the Linux zImage:
4230-------------------------
4231
4232On some platforms, it's possible to boot Linux zImage. This is done
4233using the "bootz" command. The syntax of "bootz" command is the same
4234as the syntax of "bootm" command.
4235
Tom Rini45f46d12013-05-16 11:40:11 -04004236Note, defining the CONFIG_SUPPORT_RAW_INITRD allows user to supply
Marek Vasut28850d02012-03-18 11:47:58 +00004237kernel with raw initrd images. The syntax is slightly different, the
4238address of the initrd must be augmented by it's size, in the following
4239format: "<initrd addres>:<initrd size>".
4240
stroeseb9c17c52003-04-04 15:53:41 +00004241
wdenk6c59edc2004-05-03 20:45:30 +00004242Standalone HOWTO:
4243=================
stroeseb9c17c52003-04-04 15:53:41 +00004244
wdenk6c59edc2004-05-03 20:45:30 +00004245One of the features of U-Boot is that you can dynamically load and
4246run "standalone" applications, which can use some resources of
4247U-Boot like console I/O functions or interrupt services.
stroeseb9c17c52003-04-04 15:53:41 +00004248
wdenk6c59edc2004-05-03 20:45:30 +00004249Two simple examples are included with the sources:
wdenk4fc95692003-02-28 00:49:47 +00004250
wdenk6c59edc2004-05-03 20:45:30 +00004251"Hello World" Demo:
4252-------------------
wdenkc6097192002-11-03 00:24:07 +00004253
wdenk6c59edc2004-05-03 20:45:30 +00004254'examples/hello_world.c' contains a small "Hello World" Demo
4255application; it is automatically compiled when you build U-Boot.
4256It's configured to run at address 0x00040004, so you can play with it
4257like that:
wdenkc6097192002-11-03 00:24:07 +00004258
wdenk6c59edc2004-05-03 20:45:30 +00004259 => loads
4260 ## Ready for S-Record download ...
4261 ~>examples/hello_world.srec
4262 1 2 3 4 5 6 7 8 9 10 11 ...
4263 [file transfer complete]
4264 [connected]
4265 ## Start Addr = 0x00040004
wdenkc6097192002-11-03 00:24:07 +00004266
wdenk6c59edc2004-05-03 20:45:30 +00004267 => go 40004 Hello World! This is a test.
4268 ## Starting application at 0x00040004 ...
4269 Hello World
4270 argc = 7
4271 argv[0] = "40004"
4272 argv[1] = "Hello"
4273 argv[2] = "World!"
4274 argv[3] = "This"
4275 argv[4] = "is"
4276 argv[5] = "a"
4277 argv[6] = "test."
4278 argv[7] = "<NULL>"
4279 Hit any key to exit ...
wdenkc6097192002-11-03 00:24:07 +00004280
wdenk6c59edc2004-05-03 20:45:30 +00004281 ## Application terminated, rc = 0x0
wdenkc6097192002-11-03 00:24:07 +00004282
wdenk6c59edc2004-05-03 20:45:30 +00004283Another example, which demonstrates how to register a CPM interrupt
4284handler with the U-Boot code, can be found in 'examples/timer.c'.
4285Here, a CPM timer is set up to generate an interrupt every second.
4286The interrupt service routine is trivial, just printing a '.'
4287character, but this is just a demo program. The application can be
4288controlled by the following keys:
wdenkc6097192002-11-03 00:24:07 +00004289
wdenk6c59edc2004-05-03 20:45:30 +00004290 ? - print current values og the CPM Timer registers
4291 b - enable interrupts and start timer
4292 e - stop timer and disable interrupts
4293 q - quit application
wdenkc6097192002-11-03 00:24:07 +00004294
wdenk6c59edc2004-05-03 20:45:30 +00004295 => loads
4296 ## Ready for S-Record download ...
4297 ~>examples/timer.srec
4298 1 2 3 4 5 6 7 8 9 10 11 ...
4299 [file transfer complete]
4300 [connected]
4301 ## Start Addr = 0x00040004
wdenkc6097192002-11-03 00:24:07 +00004302
wdenk6c59edc2004-05-03 20:45:30 +00004303 => go 40004
4304 ## Starting application at 0x00040004 ...
4305 TIMERS=0xfff00980
4306 Using timer 1
4307 tgcr @ 0xfff00980, tmr @ 0xfff00990, trr @ 0xfff00994, tcr @ 0xfff00998, tcn @ 0xfff0099c, ter @ 0xfff009b0
wdenkc6097192002-11-03 00:24:07 +00004308
wdenk6c59edc2004-05-03 20:45:30 +00004309Hit 'b':
4310 [q, b, e, ?] Set interval 1000000 us
4311 Enabling timer
4312Hit '?':
4313 [q, b, e, ?] ........
4314 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0xef6, ter=0x0
4315Hit '?':
4316 [q, b, e, ?] .
4317 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x2ad4, ter=0x0
4318Hit '?':
4319 [q, b, e, ?] .
4320 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x1efc, ter=0x0
4321Hit '?':
4322 [q, b, e, ?] .
4323 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x169d, ter=0x0
4324Hit 'e':
4325 [q, b, e, ?] ...Stopping timer
4326Hit 'q':
4327 [q, b, e, ?] ## Application terminated, rc = 0x0
wdenkc6097192002-11-03 00:24:07 +00004328
wdenkc6097192002-11-03 00:24:07 +00004329
wdenk6c59edc2004-05-03 20:45:30 +00004330Minicom warning:
4331================
wdenkc6097192002-11-03 00:24:07 +00004332
wdenk6c59edc2004-05-03 20:45:30 +00004333Over time, many people have reported problems when trying to use the
4334"minicom" terminal emulation program for serial download. I (wd)
4335consider minicom to be broken, and recommend not to use it. Under
4336Unix, I recommend to use C-Kermit for general purpose use (and
4337especially for kermit binary protocol download ("loadb" command), and
Karl O. Pinca0189bb2012-10-01 05:11:56 +00004338use "cu" for S-Record download ("loads" command). See
4339http://www.denx.de/wiki/view/DULG/SystemSetup#Section_4.3.
4340for help with kermit.
4341
wdenkc6097192002-11-03 00:24:07 +00004342
wdenk6c59edc2004-05-03 20:45:30 +00004343Nevertheless, if you absolutely want to use it try adding this
4344configuration to your "File transfer protocols" section:
wdenkc6097192002-11-03 00:24:07 +00004345
wdenk6c59edc2004-05-03 20:45:30 +00004346 Name Program Name U/D FullScr IO-Red. Multi
4347 X kermit /usr/bin/kermit -i -l %l -s Y U Y N N
4348 Y kermit /usr/bin/kermit -i -l %l -r N D Y N N
wdenk8dba0502003-03-31 16:34:49 +00004349
wdenk8dba0502003-03-31 16:34:49 +00004350
wdenk6c59edc2004-05-03 20:45:30 +00004351NetBSD Notes:
4352=============
wdenkc6097192002-11-03 00:24:07 +00004353
wdenk6c59edc2004-05-03 20:45:30 +00004354Starting at version 0.9.2, U-Boot supports NetBSD both as host
4355(build U-Boot) and target system (boots NetBSD/mpc8xx).
wdenk88e72a32003-06-19 23:04:19 +00004356
wdenk6c59edc2004-05-03 20:45:30 +00004357Building requires a cross environment; it is known to work on
4358NetBSD/i386 with the cross-powerpc-netbsd-1.3 package (you will also
4359need gmake since the Makefiles are not compatible with BSD make).
4360Note that the cross-powerpc package does not install include files;
4361attempting to build U-Boot will fail because <machine/ansi.h> is
4362missing. This file has to be installed and patched manually:
wdenk88e72a32003-06-19 23:04:19 +00004363
wdenk6c59edc2004-05-03 20:45:30 +00004364 # cd /usr/pkg/cross/powerpc-netbsd/include
4365 # mkdir powerpc
4366 # ln -s powerpc machine
4367 # cp /usr/src/sys/arch/powerpc/include/ansi.h powerpc/ansi.h
4368 # ${EDIT} powerpc/ansi.h ## must remove __va_list, _BSD_VA_LIST
wdenk88e72a32003-06-19 23:04:19 +00004369
wdenk6c59edc2004-05-03 20:45:30 +00004370Native builds *don't* work due to incompatibilities between native
4371and U-Boot include files.
wdenkc6097192002-11-03 00:24:07 +00004372
wdenk6c59edc2004-05-03 20:45:30 +00004373Booting assumes that (the first part of) the image booted is a
4374stage-2 loader which in turn loads and then invokes the kernel
4375proper. Loader sources will eventually appear in the NetBSD source
4376tree (probably in sys/arc/mpc8xx/stand/u-boot_stage2/); in the
wdenkd0245fc2005-04-13 10:02:42 +00004377meantime, see ftp://ftp.denx.de/pub/u-boot/ppcboot_stage2.tar.gz
wdenkc6097192002-11-03 00:24:07 +00004378
wdenkc6097192002-11-03 00:24:07 +00004379
wdenk6c59edc2004-05-03 20:45:30 +00004380Implementation Internals:
4381=========================
wdenkc6097192002-11-03 00:24:07 +00004382
wdenk6c59edc2004-05-03 20:45:30 +00004383The following is not intended to be a complete description of every
4384implementation detail. However, it should help to understand the
4385inner workings of U-Boot and make it easier to port it to custom
4386hardware.
wdenkc6097192002-11-03 00:24:07 +00004387
wdenkc6097192002-11-03 00:24:07 +00004388
wdenk6c59edc2004-05-03 20:45:30 +00004389Initial Stack, Global Data:
4390---------------------------
wdenkc6097192002-11-03 00:24:07 +00004391
wdenk6c59edc2004-05-03 20:45:30 +00004392The implementation of U-Boot is complicated by the fact that U-Boot
4393starts running out of ROM (flash memory), usually without access to
4394system RAM (because the memory controller is not initialized yet).
4395This means that we don't have writable Data or BSS segments, and BSS
4396is not initialized as zero. To be able to get a C environment working
4397at all, we have to allocate at least a minimal stack. Implementation
4398options for this are defined and restricted by the CPU used: Some CPU
4399models provide on-chip memory (like the IMMR area on MPC8xx and
4400MPC826x processors), on others (parts of) the data cache can be
4401locked as (mis-) used as memory, etc.
wdenkc6097192002-11-03 00:24:07 +00004402
Wolfgang Denkb240aef2008-03-26 10:40:12 +01004403 Chris Hallinan posted a good summary of these issues to the
Wolfgang Denk290ae6b2008-12-30 22:56:11 +01004404 U-Boot mailing list:
wdenkc6097192002-11-03 00:24:07 +00004405
wdenk6c59edc2004-05-03 20:45:30 +00004406 Subject: RE: [U-Boot-Users] RE: More On Memory Bank x (nothingness)?
4407 From: "Chris Hallinan" <clh@net1plus.com>
4408 Date: Mon, 10 Feb 2003 16:43:46 -0500 (22:43 MET)
4409 ...
wdenkc6097192002-11-03 00:24:07 +00004410
wdenk6c59edc2004-05-03 20:45:30 +00004411 Correct me if I'm wrong, folks, but the way I understand it
4412 is this: Using DCACHE as initial RAM for Stack, etc, does not
4413 require any physical RAM backing up the cache. The cleverness
4414 is that the cache is being used as a temporary supply of
4415 necessary storage before the SDRAM controller is setup. It's
Marcel Ziswilerabd8dcb2008-07-09 08:17:15 +02004416 beyond the scope of this list to explain the details, but you
wdenk6c59edc2004-05-03 20:45:30 +00004417 can see how this works by studying the cache architecture and
4418 operation in the architecture and processor-specific manuals.
wdenkc6097192002-11-03 00:24:07 +00004419
wdenk6c59edc2004-05-03 20:45:30 +00004420 OCM is On Chip Memory, which I believe the 405GP has 4K. It
4421 is another option for the system designer to use as an
Marcel Ziswilerabd8dcb2008-07-09 08:17:15 +02004422 initial stack/RAM area prior to SDRAM being available. Either
wdenk6c59edc2004-05-03 20:45:30 +00004423 option should work for you. Using CS 4 should be fine if your
4424 board designers haven't used it for something that would
4425 cause you grief during the initial boot! It is frequently not
4426 used.
wdenkc6097192002-11-03 00:24:07 +00004427
Jean-Christophe PLAGNIOL-VILLARD03836942008-10-16 15:01:15 +02004428 CONFIG_SYS_INIT_RAM_ADDR should be somewhere that won't interfere
wdenk6c59edc2004-05-03 20:45:30 +00004429 with your processor/board/system design. The default value
4430 you will find in any recent u-boot distribution in
Stefan Roese3e1f1b32005-08-01 16:49:12 +02004431 walnut.h should work for you. I'd set it to a value larger
wdenk6c59edc2004-05-03 20:45:30 +00004432 than your SDRAM module. If you have a 64MB SDRAM module, set
4433 it above 400_0000. Just make sure your board has no resources
4434 that are supposed to respond to that address! That code in
4435 start.S has been around a while and should work as is when
4436 you get the config right.
wdenk4a5c8a72003-03-06 00:02:04 +00004437
wdenk6c59edc2004-05-03 20:45:30 +00004438 -Chris Hallinan
4439 DS4.COM, Inc.
wdenk4a5c8a72003-03-06 00:02:04 +00004440
wdenk6c59edc2004-05-03 20:45:30 +00004441It is essential to remember this, since it has some impact on the C
4442code for the initialization procedures:
wdenk4a5c8a72003-03-06 00:02:04 +00004443
wdenk6c59edc2004-05-03 20:45:30 +00004444* Initialized global data (data segment) is read-only. Do not attempt
4445 to write it.
wdenk4a5c8a72003-03-06 00:02:04 +00004446
Jeremiah Mahler03f930c2015-01-04 18:56:50 -08004447* Do not use any uninitialized global data (or implicitly initialized
wdenk6c59edc2004-05-03 20:45:30 +00004448 as zero data - BSS segment) at all - this is undefined, initiali-
4449 zation is performed later (when relocating to RAM).
wdenk4a5c8a72003-03-06 00:02:04 +00004450
wdenk6c59edc2004-05-03 20:45:30 +00004451* Stack space is very limited. Avoid big data buffers or things like
4452 that.
wdenk4a5c8a72003-03-06 00:02:04 +00004453
wdenk6c59edc2004-05-03 20:45:30 +00004454Having only the stack as writable memory limits means we cannot use
Jeremiah Mahler03f930c2015-01-04 18:56:50 -08004455normal global data to share information between the code. But it
wdenk6c59edc2004-05-03 20:45:30 +00004456turned out that the implementation of U-Boot can be greatly
4457simplified by making a global data structure (gd_t) available to all
4458functions. We could pass a pointer to this data as argument to _all_
4459functions, but this would bloat the code. Instead we use a feature of
4460the GCC compiler (Global Register Variables) to share the data: we
4461place a pointer (gd) to the global data into a register which we
4462reserve for this purpose.
wdenkc6097192002-11-03 00:24:07 +00004463
wdenk6c59edc2004-05-03 20:45:30 +00004464When choosing a register for such a purpose we are restricted by the
4465relevant (E)ABI specifications for the current architecture, and by
4466GCC's implementation.
wdenkc6097192002-11-03 00:24:07 +00004467
wdenk6c59edc2004-05-03 20:45:30 +00004468For PowerPC, the following registers have specific use:
4469 R1: stack pointer
Wolfgang Denk69c09642008-02-14 22:43:22 +01004470 R2: reserved for system use
wdenk6c59edc2004-05-03 20:45:30 +00004471 R3-R4: parameter passing and return values
4472 R5-R10: parameter passing
4473 R13: small data area pointer
4474 R30: GOT pointer
4475 R31: frame pointer
wdenkc6097192002-11-03 00:24:07 +00004476
Joakim Tjernlund693c0c12010-01-19 14:41:58 +01004477 (U-Boot also uses R12 as internal GOT pointer. r12
4478 is a volatile register so r12 needs to be reset when
4479 going back and forth between asm and C)
wdenkc6097192002-11-03 00:24:07 +00004480
Wolfgang Denk69c09642008-02-14 22:43:22 +01004481 ==> U-Boot will use R2 to hold a pointer to the global data
wdenkc6097192002-11-03 00:24:07 +00004482
wdenk6c59edc2004-05-03 20:45:30 +00004483 Note: on PPC, we could use a static initializer (since the
4484 address of the global data structure is known at compile time),
4485 but it turned out that reserving a register results in somewhat
4486 smaller code - although the code savings are not that big (on
4487 average for all boards 752 bytes for the whole U-Boot image,
4488 624 text + 127 data).
wdenkc6097192002-11-03 00:24:07 +00004489
wdenk6c59edc2004-05-03 20:45:30 +00004490On ARM, the following registers are used:
wdenkc6097192002-11-03 00:24:07 +00004491
wdenk6c59edc2004-05-03 20:45:30 +00004492 R0: function argument word/integer result
4493 R1-R3: function argument word
Jeroen Hofsteea556aca2013-09-21 14:04:42 +02004494 R9: platform specific
4495 R10: stack limit (used only if stack checking is enabled)
wdenk6c59edc2004-05-03 20:45:30 +00004496 R11: argument (frame) pointer
4497 R12: temporary workspace
4498 R13: stack pointer
4499 R14: link register
4500 R15: program counter
wdenkc6097192002-11-03 00:24:07 +00004501
Jeroen Hofsteea556aca2013-09-21 14:04:42 +02004502 ==> U-Boot will use R9 to hold a pointer to the global data
4503
4504 Note: on ARM, only R_ARM_RELATIVE relocations are supported.
wdenkc6097192002-11-03 00:24:07 +00004505
Thomas Chou8fa38582010-05-21 11:08:03 +08004506On Nios II, the ABI is documented here:
4507 http://www.altera.com/literature/hb/nios2/n2cpu_nii51016.pdf
4508
4509 ==> U-Boot will use gp to hold a pointer to the global data
4510
4511 Note: on Nios II, we give "-G0" option to gcc and don't use gp
4512 to access small data sections, so gp is free.
4513
Macpaul Lin1cac36e2011-10-19 20:41:11 +00004514On NDS32, the following registers are used:
4515
4516 R0-R1: argument/return
4517 R2-R5: argument
4518 R15: temporary register for assembler
4519 R16: trampoline register
4520 R28: frame pointer (FP)
4521 R29: global pointer (GP)
4522 R30: link register (LP)
4523 R31: stack pointer (SP)
4524 PC: program counter (PC)
4525
4526 ==> U-Boot will use R10 to hold a pointer to the global data
4527
Wolfgang Denk6405a152006-03-31 18:32:53 +02004528NOTE: DECLARE_GLOBAL_DATA_PTR must be used with file-global scope,
4529or current versions of GCC may "optimize" the code too much.
wdenkc6097192002-11-03 00:24:07 +00004530
Rick Chend7e6f922017-12-26 13:55:59 +08004531On RISC-V, the following registers are used:
4532
4533 x0: hard-wired zero (zero)
4534 x1: return address (ra)
4535 x2: stack pointer (sp)
4536 x3: global pointer (gp)
4537 x4: thread pointer (tp)
4538 x5: link register (t0)
4539 x8: frame pointer (fp)
4540 x10-x11: arguments/return values (a0-1)
4541 x12-x17: arguments (a2-7)
4542 x28-31: temporaries (t3-6)
4543 pc: program counter (pc)
4544
4545 ==> U-Boot will use gp to hold a pointer to the global data
4546
wdenk6c59edc2004-05-03 20:45:30 +00004547Memory Management:
4548------------------
wdenkc6097192002-11-03 00:24:07 +00004549
wdenk6c59edc2004-05-03 20:45:30 +00004550U-Boot runs in system state and uses physical addresses, i.e. the
4551MMU is not used either for address mapping nor for memory protection.
wdenkc6097192002-11-03 00:24:07 +00004552
wdenk6c59edc2004-05-03 20:45:30 +00004553The available memory is mapped to fixed addresses using the memory
4554controller. In this process, a contiguous block is formed for each
4555memory type (Flash, SDRAM, SRAM), even when it consists of several
4556physical memory banks.
wdenkc6097192002-11-03 00:24:07 +00004557
wdenk6c59edc2004-05-03 20:45:30 +00004558U-Boot is installed in the first 128 kB of the first Flash bank (on
4559TQM8xxL modules this is the range 0x40000000 ... 0x4001FFFF). After
4560booting and sizing and initializing DRAM, the code relocates itself
4561to the upper end of DRAM. Immediately below the U-Boot code some
Jean-Christophe PLAGNIOL-VILLARD03836942008-10-16 15:01:15 +02004562memory is reserved for use by malloc() [see CONFIG_SYS_MALLOC_LEN
wdenk6c59edc2004-05-03 20:45:30 +00004563configuration setting]. Below that, a structure with global Board
4564Info data is placed, followed by the stack (growing downward).
wdenkc6097192002-11-03 00:24:07 +00004565
wdenk6c59edc2004-05-03 20:45:30 +00004566Additionally, some exception handler code is copied to the low 8 kB
4567of DRAM (0x00000000 ... 0x00001FFF).
wdenkc6097192002-11-03 00:24:07 +00004568
wdenk6c59edc2004-05-03 20:45:30 +00004569So a typical memory configuration with 16 MB of DRAM could look like
4570this:
wdenkc6097192002-11-03 00:24:07 +00004571
wdenk6c59edc2004-05-03 20:45:30 +00004572 0x0000 0000 Exception Vector code
4573 :
4574 0x0000 1FFF
4575 0x0000 2000 Free for Application Use
4576 :
4577 :
wdenkc6097192002-11-03 00:24:07 +00004578
wdenk6c59edc2004-05-03 20:45:30 +00004579 :
4580 :
4581 0x00FB FF20 Monitor Stack (Growing downward)
4582 0x00FB FFAC Board Info Data and permanent copy of global data
4583 0x00FC 0000 Malloc Arena
4584 :
4585 0x00FD FFFF
4586 0x00FE 0000 RAM Copy of Monitor Code
4587 ... eventually: LCD or video framebuffer
4588 ... eventually: pRAM (Protected RAM - unchanged by reset)
4589 0x00FF FFFF [End of RAM]
wdenkc6097192002-11-03 00:24:07 +00004590
wdenkc6097192002-11-03 00:24:07 +00004591
wdenk6c59edc2004-05-03 20:45:30 +00004592System Initialization:
4593----------------------
wdenkc6097192002-11-03 00:24:07 +00004594
wdenk6c59edc2004-05-03 20:45:30 +00004595In the reset configuration, U-Boot starts at the reset entry point
Marcel Ziswilerabd8dcb2008-07-09 08:17:15 +02004596(on most PowerPC systems at address 0x00000100). Because of the reset
Jeremiah Mahler03f930c2015-01-04 18:56:50 -08004597configuration for CS0# this is a mirror of the on board Flash memory.
wdenk6c59edc2004-05-03 20:45:30 +00004598To be able to re-map memory U-Boot then jumps to its link address.
4599To be able to implement the initialization code in C, a (small!)
4600initial stack is set up in the internal Dual Ported RAM (in case CPUs
Heiko Schocher71cb3e92017-06-07 17:33:10 +02004601which provide such a feature like), or in a locked part of the data
4602cache. After that, U-Boot initializes the CPU core, the caches and
4603the SIU.
wdenkc6097192002-11-03 00:24:07 +00004604
wdenk6c59edc2004-05-03 20:45:30 +00004605Next, all (potentially) available memory banks are mapped using a
4606preliminary mapping. For example, we put them on 512 MB boundaries
4607(multiples of 0x20000000: SDRAM on 0x00000000 and 0x20000000, Flash
4608on 0x40000000 and 0x60000000, SRAM on 0x80000000). Then UPM A is
4609programmed for SDRAM access. Using the temporary configuration, a
4610simple memory test is run that determines the size of the SDRAM
4611banks.
wdenkc6097192002-11-03 00:24:07 +00004612
wdenk6c59edc2004-05-03 20:45:30 +00004613When there is more than one SDRAM bank, and the banks are of
4614different size, the largest is mapped first. For equal size, the first
4615bank (CS2#) is mapped first. The first mapping is always for address
46160x00000000, with any additional banks following immediately to create
4617contiguous memory starting from 0.
wdenkc6097192002-11-03 00:24:07 +00004618
wdenk6c59edc2004-05-03 20:45:30 +00004619Then, the monitor installs itself at the upper end of the SDRAM area
4620and allocates memory for use by malloc() and for the global Board
4621Info data; also, the exception vector code is copied to the low RAM
4622pages, and the final stack is set up.
wdenkc6097192002-11-03 00:24:07 +00004623
wdenk6c59edc2004-05-03 20:45:30 +00004624Only after this relocation will you have a "normal" C environment;
4625until that you are restricted in several ways, mostly because you are
4626running from ROM, and because the code will have to be relocated to a
4627new address in RAM.
wdenkc6097192002-11-03 00:24:07 +00004628
wdenkc6097192002-11-03 00:24:07 +00004629
wdenk6c59edc2004-05-03 20:45:30 +00004630U-Boot Porting Guide:
4631----------------------
wdenkc6097192002-11-03 00:24:07 +00004632
wdenk6c59edc2004-05-03 20:45:30 +00004633[Based on messages by Jerry Van Baren in the U-Boot-Users mailing
4634list, October 2002]
wdenkc6097192002-11-03 00:24:07 +00004635
wdenkc6097192002-11-03 00:24:07 +00004636
Jerry Van Barenba0687c2009-07-15 20:42:59 -04004637int main(int argc, char *argv[])
wdenk6c59edc2004-05-03 20:45:30 +00004638{
4639 sighandler_t no_more_time;
wdenkc6097192002-11-03 00:24:07 +00004640
Jerry Van Barenba0687c2009-07-15 20:42:59 -04004641 signal(SIGALRM, no_more_time);
4642 alarm(PROJECT_DEADLINE - toSec (3 * WEEK));
wdenkc6097192002-11-03 00:24:07 +00004643
wdenk6c59edc2004-05-03 20:45:30 +00004644 if (available_money > available_manpower) {
Jerry Van Barenba0687c2009-07-15 20:42:59 -04004645 Pay consultant to port U-Boot;
wdenk6c59edc2004-05-03 20:45:30 +00004646 return 0;
4647 }
wdenkc6097192002-11-03 00:24:07 +00004648
wdenk6c59edc2004-05-03 20:45:30 +00004649 Download latest U-Boot source;
wdenk34b613e2002-12-17 01:51:00 +00004650
Wolfgang Denk290ae6b2008-12-30 22:56:11 +01004651 Subscribe to u-boot mailing list;
wdenkc6097192002-11-03 00:24:07 +00004652
Jerry Van Barenba0687c2009-07-15 20:42:59 -04004653 if (clueless)
4654 email("Hi, I am new to U-Boot, how do I get started?");
wdenkc6097192002-11-03 00:24:07 +00004655
wdenk6c59edc2004-05-03 20:45:30 +00004656 while (learning) {
4657 Read the README file in the top level directory;
Jerry Van Barenba0687c2009-07-15 20:42:59 -04004658 Read http://www.denx.de/twiki/bin/view/DULG/Manual;
4659 Read applicable doc/*.README;
wdenk6c59edc2004-05-03 20:45:30 +00004660 Read the source, Luke;
Jerry Van Barenba0687c2009-07-15 20:42:59 -04004661 /* find . -name "*.[chS]" | xargs grep -i <keyword> */
wdenk6c59edc2004-05-03 20:45:30 +00004662 }
wdenkc6097192002-11-03 00:24:07 +00004663
Jerry Van Barenba0687c2009-07-15 20:42:59 -04004664 if (available_money > toLocalCurrency ($2500))
4665 Buy a BDI3000;
4666 else
wdenk6c59edc2004-05-03 20:45:30 +00004667 Add a lot of aggravation and time;
wdenkc6097192002-11-03 00:24:07 +00004668
Jerry Van Barenba0687c2009-07-15 20:42:59 -04004669 if (a similar board exists) { /* hopefully... */
4670 cp -a board/<similar> board/<myboard>
4671 cp include/configs/<similar>.h include/configs/<myboard>.h
4672 } else {
4673 Create your own board support subdirectory;
4674 Create your own board include/configs/<myboard>.h file;
4675 }
4676 Edit new board/<myboard> files
4677 Edit new include/configs/<myboard>.h
wdenkc6097192002-11-03 00:24:07 +00004678
Jerry Van Barenba0687c2009-07-15 20:42:59 -04004679 while (!accepted) {
4680 while (!running) {
4681 do {
4682 Add / modify source code;
4683 } until (compiles);
4684 Debug;
4685 if (clueless)
4686 email("Hi, I am having problems...");
4687 }
4688 Send patch file to the U-Boot email list;
4689 if (reasonable critiques)
4690 Incorporate improvements from email list code review;
4691 else
4692 Defend code as written;
wdenk634d2f72004-04-15 23:14:49 +00004693 }
wdenkc6097192002-11-03 00:24:07 +00004694
wdenk6c59edc2004-05-03 20:45:30 +00004695 return 0;
4696}
wdenkc6097192002-11-03 00:24:07 +00004697
wdenk6c59edc2004-05-03 20:45:30 +00004698void no_more_time (int sig)
4699{
4700 hire_a_guru();
4701}
wdenkc6097192002-11-03 00:24:07 +00004702
wdenkc6097192002-11-03 00:24:07 +00004703
wdenk6c59edc2004-05-03 20:45:30 +00004704Coding Standards:
4705-----------------
wdenkc6097192002-11-03 00:24:07 +00004706
wdenk6c59edc2004-05-03 20:45:30 +00004707All contributions to U-Boot should conform to the Linux kernel
Baruch Siachb1081252017-12-10 17:34:35 +02004708coding style; see the kernel coding style guide at
4709https://www.kernel.org/doc/html/latest/process/coding-style.html, and the
4710script "scripts/Lindent" in your Linux kernel source directory.
Detlev Zundelaa63d482006-09-01 15:39:02 +02004711
4712Source files originating from a different project (for example the
4713MTD subsystem) are generally exempt from these guidelines and are not
Jeremiah Mahler03f930c2015-01-04 18:56:50 -08004714reformatted to ease subsequent migration to newer versions of those
Detlev Zundelaa63d482006-09-01 15:39:02 +02004715sources.
wdenkc6097192002-11-03 00:24:07 +00004716
Detlev Zundelaa63d482006-09-01 15:39:02 +02004717Please note that U-Boot is implemented in C (and to some small parts in
4718Assembler); no C++ is used, so please do not use C++ style comments (//)
4719in your code.
wdenkad276f22004-01-04 16:28:35 +00004720
wdenk6c59edc2004-05-03 20:45:30 +00004721Please also stick to the following formatting rules:
4722- remove any trailing white space
Wolfgang Denk20bd2a62011-07-27 10:59:55 +00004723- use TAB characters for indentation and vertical alignment, not spaces
wdenk6c59edc2004-05-03 20:45:30 +00004724- make sure NOT to use DOS '\r\n' line feeds
Wolfgang Denk20bd2a62011-07-27 10:59:55 +00004725- do not add more than 2 consecutive empty lines to source files
wdenk6c59edc2004-05-03 20:45:30 +00004726- do not add trailing empty lines to source files
wdenkc6097192002-11-03 00:24:07 +00004727
wdenk6c59edc2004-05-03 20:45:30 +00004728Submissions which do not conform to the standards may be returned
4729with a request to reformat the changes.
wdenkc6097192002-11-03 00:24:07 +00004730
wdenkc6097192002-11-03 00:24:07 +00004731
wdenk6c59edc2004-05-03 20:45:30 +00004732Submitting Patches:
4733-------------------
wdenkc6097192002-11-03 00:24:07 +00004734
wdenk6c59edc2004-05-03 20:45:30 +00004735Since the number of patches for U-Boot is growing, we need to
4736establish some rules. Submissions which do not conform to these rules
4737may be rejected, even when they contain important and valuable stuff.
wdenkc6097192002-11-03 00:24:07 +00004738
Magnus Liljaf3b287b2008-08-06 19:32:33 +02004739Please see http://www.denx.de/wiki/U-Boot/Patches for details.
Wolfgang Denkb240aef2008-03-26 10:40:12 +01004740
Wolfgang Denk290ae6b2008-12-30 22:56:11 +01004741Patches shall be sent to the u-boot mailing list <u-boot@lists.denx.de>;
S. Lockwood-Childsda6d34c2017-11-14 22:56:42 -08004742see https://lists.denx.de/listinfo/u-boot
Wolfgang Denk290ae6b2008-12-30 22:56:11 +01004743
wdenk6c59edc2004-05-03 20:45:30 +00004744When you send a patch, please include the following information with
4745it:
wdenkc6097192002-11-03 00:24:07 +00004746
wdenk6c59edc2004-05-03 20:45:30 +00004747* For bug fixes: a description of the bug and how your patch fixes
4748 this bug. Please try to include a way of demonstrating that the
4749 patch actually fixes something.
wdenkc6097192002-11-03 00:24:07 +00004750
wdenk6c59edc2004-05-03 20:45:30 +00004751* For new features: a description of the feature and your
4752 implementation.
wdenkc6097192002-11-03 00:24:07 +00004753
wdenk6c59edc2004-05-03 20:45:30 +00004754* A CHANGELOG entry as plaintext (separate from the patch)
wdenkc6097192002-11-03 00:24:07 +00004755
Robert P. J. Day076ed9b2015-12-19 07:16:10 -05004756* For major contributions, add a MAINTAINERS file with your
4757 information and associated file and directory references.
wdenkc6097192002-11-03 00:24:07 +00004758
Albert ARIBAUD48e910f2013-09-11 15:52:51 +02004759* When you add support for a new board, don't forget to add a
4760 maintainer e-mail address to the boards.cfg file, too.
wdenkc6097192002-11-03 00:24:07 +00004761
wdenk6c59edc2004-05-03 20:45:30 +00004762* If your patch adds new configuration options, don't forget to
4763 document these in the README file.
wdenkc6097192002-11-03 00:24:07 +00004764
Wolfgang Denkb240aef2008-03-26 10:40:12 +01004765* The patch itself. If you are using git (which is *strongly*
4766 recommended) you can easily generate the patch using the
Wolfgang Denk20bd2a62011-07-27 10:59:55 +00004767 "git format-patch". If you then use "git send-email" to send it to
Wolfgang Denkb240aef2008-03-26 10:40:12 +01004768 the U-Boot mailing list, you will avoid most of the common problems
4769 with some other mail clients.
wdenkca9bc762003-07-15 07:45:49 +00004770
Wolfgang Denkb240aef2008-03-26 10:40:12 +01004771 If you cannot use git, use "diff -purN OLD NEW". If your version of
4772 diff does not support these options, then get the latest version of
4773 GNU diff.
wdenkc6097192002-11-03 00:24:07 +00004774
Wolfgang Denkb240aef2008-03-26 10:40:12 +01004775 The current directory when running this command shall be the parent
4776 directory of the U-Boot source tree (i. e. please make sure that
4777 your patch includes sufficient directory information for the
4778 affected files).
4779
4780 We prefer patches as plain text. MIME attachments are discouraged,
4781 and compressed attachments must not be used.
wdenk88e72a32003-06-19 23:04:19 +00004782
wdenk6c59edc2004-05-03 20:45:30 +00004783* If one logical set of modifications affects or creates several
4784 files, all these changes shall be submitted in a SINGLE patch file.
wdenk57b2d802003-06-27 21:31:46 +00004785
wdenk6c59edc2004-05-03 20:45:30 +00004786* Changesets that contain different, unrelated modifications shall be
4787 submitted as SEPARATE patches, one patch per changeset.
wdenk88e72a32003-06-19 23:04:19 +00004788
wdenkc6097192002-11-03 00:24:07 +00004789
wdenk6c59edc2004-05-03 20:45:30 +00004790Notes:
wdenkc6097192002-11-03 00:24:07 +00004791
Simon Glassdc27def2016-07-27 20:33:08 -06004792* Before sending the patch, run the buildman script on your patched
wdenk6c59edc2004-05-03 20:45:30 +00004793 source tree and make sure that no errors or warnings are reported
4794 for any of the boards.
4795
4796* Keep your modifications to the necessary minimum: A patch
4797 containing several unrelated changes or arbitrary reformats will be
4798 returned with a request to re-formatting / split it.
wdenkc6097192002-11-03 00:24:07 +00004799
wdenk6c59edc2004-05-03 20:45:30 +00004800* If you modify existing code, make sure that your new code does not
4801 add to the memory footprint of the code ;-) Small is beautiful!
4802 When adding new features, these should compile conditionally only
4803 (using #ifdef), and the resulting code with the new feature
4804 disabled must not need more memory than the old code without your
4805 modification.
wdenkcbc49a52005-05-03 14:12:25 +00004806
Wolfgang Denk290ae6b2008-12-30 22:56:11 +01004807* Remember that there is a size limit of 100 kB per message on the
4808 u-boot mailing list. Bigger patches will be moderated. If they are
4809 reasonable and not too big, they will be acknowledged. But patches
4810 bigger than the size limit should be avoided.