blob: ebfdced4a725384a655423b7d9bc527a996e4961 [file] [log] [blame]
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.
Naoki Hayama2bc50c22020-10-08 13:16:18 +090054Please see https://lists.denx.de/pipermail/u-boot and
55https://marc.info/?l=u-boot
wdenkc6097192002-11-03 00:24:07 +000056
Wolfgang Denkb240aef2008-03-26 10:40:12 +010057Where to get source code:
58=========================
59
Robert P. J. Day076ed9b2015-12-19 07:16:10 -050060The U-Boot source code is maintained in the Git repository at
Heinrich Schuchardt28b2b852021-02-24 13:19:04 +010061https://source.denx.de/u-boot/u-boot.git ; you can browse it online at
62https://source.denx.de/u-boot/u-boot
Wolfgang Denkb240aef2008-03-26 10:40:12 +010063
Naoki Hayama65ae68a2020-10-08 13:16:25 +090064The "Tags" links on this page allow you to download tarballs of
Marcel Ziswilerabd8dcb2008-07-09 08:17:15 +020065any version you might be interested in. Official releases are also
Naoki Hayama65ae68a2020-10-08 13:16:25 +090066available from the DENX file server through HTTPS or FTP.
67https://ftp.denx.de/pub/u-boot/
68ftp://ftp.denx.de/pub/u-boot/
Wolfgang Denkb240aef2008-03-26 10:40:12 +010069
70
wdenkc6097192002-11-03 00:24:07 +000071Where we come from:
72===================
73
74- start from 8xxrom sources
Naoki Hayamae0cc1852020-10-08 13:17:16 +090075- create PPCBoot project (https://sourceforge.net/projects/ppcboot)
wdenkc6097192002-11-03 00:24:07 +000076- clean up code
77- make it easier to add custom boards
78- make it possible to add other [PowerPC] CPUs
79- extend functions, especially:
80 * Provide extended interface to Linux boot loader
81 * S-Record download
82 * network boot
Simon Glassaaef3bf2019-08-01 09:47:14 -060083 * ATA disk / SCSI ... boot
Naoki Hayamae0cc1852020-10-08 13:17:16 +090084- create ARMBoot project (https://sourceforge.net/projects/armboot)
wdenkc6097192002-11-03 00:24:07 +000085- add other CPU families (starting with ARM)
Naoki Hayamae0cc1852020-10-08 13:17:16 +090086- create U-Boot project (https://sourceforge.net/projects/u-boot)
87- current project page: see https://www.denx.de/wiki/U-Boot
wdenk24ee89b2002-11-03 17:56:27 +000088
89
90Names and Spelling:
91===================
92
93The "official" name of this project is "Das U-Boot". The spelling
94"U-Boot" shall be used in all written text (documentation, comments
95in source files etc.). Example:
96
97 This is the README file for the U-Boot project.
98
99File names etc. shall be based on the string "u-boot". Examples:
100
101 include/asm-ppc/u-boot.h
102
103 #include <asm/u-boot.h>
104
105Variable names, preprocessor constants etc. shall be either based on
106the string "u_boot" or on "U_BOOT". Example:
wdenkc6097192002-11-03 00:24:07 +0000107
wdenk24ee89b2002-11-03 17:56:27 +0000108 U_BOOT_VERSION u_boot_logo
109 IH_OS_U_BOOT u_boot_hush_start
110
wdenkc6097192002-11-03 00:24:07 +0000111
wdenk7474aca2002-12-17 17:55:09 +0000112Versioning:
113===========
114
Thomas Webere89e6282010-09-28 08:06:25 +0200115Starting with the release in October 2008, the names of the releases
116were changed from numerical release numbers without deeper meaning
117into a time stamp based numbering. Regular releases are identified by
118names consisting of the calendar year and month of the release date.
119Additional fields (if present) indicate release candidates or bug fix
120releases in "stable" maintenance trees.
wdenk7474aca2002-12-17 17:55:09 +0000121
Thomas Webere89e6282010-09-28 08:06:25 +0200122Examples:
Wolfgang Denk092ae952011-10-26 10:21:21 +0000123 U-Boot v2009.11 - Release November 2009
Thomas Webere89e6282010-09-28 08:06:25 +0200124 U-Boot v2009.11.1 - Release 1 in version November 2009 stable tree
Jelle van der Waa30245ca2016-10-30 17:30:30 +0100125 U-Boot v2010.09-rc1 - Release candidate 1 for September 2010 release
wdenk7474aca2002-12-17 17:55:09 +0000126
127
wdenkc6097192002-11-03 00:24:07 +0000128Directory Hierarchy:
129====================
130
Simon Glass1a0a4ac2021-07-10 21:14:21 -0600131/arch Architecture-specific files
Masahiro Yamadaef6ebff2014-03-07 18:02:02 +0900132 /arc Files generic to ARC architecture
Peter Tysere4d1abc2010-04-12 22:28:21 -0500133 /arm Files generic to ARM architecture
Peter Tysere4d1abc2010-04-12 22:28:21 -0500134 /m68k Files generic to m68k architecture
Peter Tysere4d1abc2010-04-12 22:28:21 -0500135 /microblaze Files generic to microblaze architecture
Peter Tysere4d1abc2010-04-12 22:28:21 -0500136 /mips Files generic to MIPS architecture
Peter Tysere4d1abc2010-04-12 22:28:21 -0500137 /nios2 Files generic to Altera NIOS2 architecture
Stefan Roese88fbf932010-04-15 16:07:28 +0200138 /powerpc Files generic to PowerPC architecture
Rick Chend7e6f922017-12-26 13:55:59 +0800139 /riscv Files generic to RISC-V architecture
Robert P. J. Day076ed9b2015-12-19 07:16:10 -0500140 /sandbox Files generic to HW-independent "sandbox"
Peter Tysere4d1abc2010-04-12 22:28:21 -0500141 /sh Files generic to SH architecture
Robert P. J. Daya269c932013-09-15 18:34:15 -0400142 /x86 Files generic to x86 architecture
Naoki Hayama411f5c62020-10-08 13:16:38 +0900143 /xtensa Files generic to Xtensa architecture
Simon Glass1a0a4ac2021-07-10 21:14:21 -0600144/api Machine/arch-independent API for external apps
145/board Board-dependent files
Simon Glass91944df2021-10-14 12:47:54 -0600146/boot Support for images and booting
Xu Ziyuanfb1f9392016-08-26 19:54:49 +0800147/cmd U-Boot commands functions
Simon Glass1a0a4ac2021-07-10 21:14:21 -0600148/common Misc architecture-independent functions
Robert P. J. Day076ed9b2015-12-19 07:16:10 -0500149/configs Board default configuration files
Peter Tysere4d1abc2010-04-12 22:28:21 -0500150/disk Code for disk drive partition handling
Simon Glass1a0a4ac2021-07-10 21:14:21 -0600151/doc Documentation (a mix of ReST and READMEs)
152/drivers Device drivers
153/dts Makefile for building internal U-Boot fdt.
154/env Environment support
Peter Tysere4d1abc2010-04-12 22:28:21 -0500155/examples Example code for standalone applications, etc.
156/fs Filesystem code (cramfs, ext2, jffs2, etc.)
157/include Header Files
Robert P. J. Day076ed9b2015-12-19 07:16:10 -0500158/lib Library routines generic to all architectures
159/Licenses Various license files
Peter Tysere4d1abc2010-04-12 22:28:21 -0500160/net Networking code
161/post Power On Self Test
Robert P. J. Day076ed9b2015-12-19 07:16:10 -0500162/scripts Various build scripts and Makefiles
163/test Various unit test files
Simon Glass1a0a4ac2021-07-10 21:14:21 -0600164/tools Tools to build and sign FIT images, etc.
wdenkc6097192002-11-03 00:24:07 +0000165
wdenkc6097192002-11-03 00:24:07 +0000166Software Configuration:
167=======================
168
wdenkc6097192002-11-03 00:24:07 +0000169Selection of Processor Architecture and Board Type:
170---------------------------------------------------
171
172For all supported boards there are ready-to-use default
Holger Freyther7ba4e572014-08-04 09:26:05 +0200173configurations available; just type "make <board_name>_defconfig".
wdenkc6097192002-11-03 00:24:07 +0000174
175Example: For a TQM823L module type:
176
177 cd u-boot
Holger Freyther7ba4e572014-08-04 09:26:05 +0200178 make TQM823L_defconfig
wdenkc6097192002-11-03 00:24:07 +0000179
Robert P. J. Day076ed9b2015-12-19 07:16:10 -0500180Note: If you're looking for the default configuration file for a board
181you're sure used to be there but is now missing, check the file
182doc/README.scrapyard for a list of no longer supported boards.
wdenkc6097192002-11-03 00:24:07 +0000183
Simon Glass53552c92014-03-22 17:12:59 -0600184Sandbox Environment:
185--------------------
186
187U-Boot can be built natively to run on a Linux host using the 'sandbox'
188board. This allows feature development which is not board- or architecture-
189specific to be undertaken on a native platform. The sandbox is also used to
190run some of U-Boot's tests.
191
Naoki Hayamadd860ca2020-10-08 13:16:58 +0900192See doc/arch/sandbox.rst for more details.
Simon Glass53552c92014-03-22 17:12:59 -0600193
194
Simon Glassd8711af2015-03-03 08:03:00 -0700195Board Initialisation Flow:
196--------------------------
197
198This is the intended start-up flow for boards. This should apply for both
Robert P. J. Day076ed9b2015-12-19 07:16:10 -0500199SPL and U-Boot proper (i.e. they both follow the same rules).
200
201Note: "SPL" stands for "Secondary Program Loader," which is explained in
202more detail later in this file.
203
204At present, SPL mostly uses a separate code path, but the function names
205and roles of each function are the same. Some boards or architectures
206may not conform to this. At least most ARM boards which use
207CONFIG_SPL_FRAMEWORK conform to this.
Simon Glassd8711af2015-03-03 08:03:00 -0700208
Robert P. J. Day076ed9b2015-12-19 07:16:10 -0500209Execution typically starts with an architecture-specific (and possibly
210CPU-specific) start.S file, such as:
211
212 - arch/arm/cpu/armv7/start.S
213 - arch/powerpc/cpu/mpc83xx/start.S
214 - arch/mips/cpu/start.S
215
216and so on. From there, three functions are called; the purpose and
217limitations of each of these functions are described below.
Simon Glassd8711af2015-03-03 08:03:00 -0700218
219lowlevel_init():
220 - purpose: essential init to permit execution to reach board_init_f()
221 - no global_data or BSS
222 - there is no stack (ARMv7 may have one but it will soon be removed)
223 - must not set up SDRAM or use console
224 - must only do the bare minimum to allow execution to continue to
225 board_init_f()
226 - this is almost never needed
227 - return normally from this function
228
229board_init_f():
230 - purpose: set up the machine ready for running board_init_r():
231 i.e. SDRAM and serial UART
232 - global_data is available
233 - stack is in SRAM
234 - BSS is not available, so you cannot use global/static variables,
235 only stack variables and global_data
236
237 Non-SPL-specific notes:
238 - dram_init() is called to set up DRAM. If already done in SPL this
239 can do nothing
240
241 SPL-specific notes:
242 - you can override the entire board_init_f() function with your own
243 version as needed.
244 - preloader_console_init() can be called here in extremis
245 - should set up SDRAM, and anything needed to make the UART work
Naoki Hayamaebfd8192020-09-24 15:57:19 +0900246 - there is no need to clear BSS, it will be done by crt0.S
Andreas Dannenberg7673bed2019-08-08 12:54:49 -0500247 - for specific scenarios on certain architectures an early BSS *can*
248 be made available (via CONFIG_SPL_EARLY_BSS by moving the clearing
249 of BSS prior to entering board_init_f()) but doing so is discouraged.
250 Instead it is strongly recommended to architect any code changes
251 or additions such to not depend on the availability of BSS during
252 board_init_f() as indicated in other sections of this README to
253 maintain compatibility and consistency across the entire code base.
Simon Glassd8711af2015-03-03 08:03:00 -0700254 - must return normally from this function (don't call board_init_r()
255 directly)
256
257Here the BSS is cleared. For SPL, if CONFIG_SPL_STACK_R is defined, then at
258this point the stack and global_data are relocated to below
259CONFIG_SPL_STACK_R_ADDR. For non-SPL, U-Boot is relocated to run at the top of
260memory.
261
262board_init_r():
263 - purpose: main execution, common code
264 - global_data is available
265 - SDRAM is available
266 - BSS is available, all static/global variables can be used
267 - execution eventually continues to main_loop()
268
269 Non-SPL-specific notes:
270 - U-Boot is relocated to the top of memory and is now running from
271 there.
272
273 SPL-specific notes:
274 - stack is optionally in SDRAM, if CONFIG_SPL_STACK_R is defined and
Ashish Kumar11234062017-08-11 11:09:14 +0530275 CONFIG_SYS_FSL_HAS_CCI400
276
277 Defined For SoC that has cache coherent interconnect
278 CCN-400
wdenk1272e232002-11-10 22:06:23 +0000279
Ashish Kumar97393d62017-08-18 10:54:36 +0530280 CONFIG_SYS_FSL_HAS_CCN504
281
282 Defined for SoC that has cache coherent interconnect CCN-504
283
wdenkc6097192002-11-03 00:24:07 +0000284The following options need to be configured:
285
Kim Phillips203fee32007-08-10 13:28:25 -0500286- CPU Type: Define exactly one, e.g. CONFIG_MPC85XX.
wdenkc6097192002-11-03 00:24:07 +0000287
Kim Phillips203fee32007-08-10 13:28:25 -0500288- Board Type: Define exactly one, e.g. CONFIG_MPC8540ADS.
Wolfgang Denk994ad962006-10-24 14:42:37 +0200289
Kumar Galaf4fb90f2011-02-18 05:40:54 -0600290- 85xx CPU Options:
York Sun2394a0f2012-10-08 07:44:30 +0000291 CONFIG_SYS_PPC64
292
293 Specifies that the core is a 64-bit PowerPC implementation (implements
294 the "64" category of the Power ISA). This is necessary for ePAPR
295 compliance, among other possible reasons.
296
Kumar Galaf4fb90f2011-02-18 05:40:54 -0600297 CONFIG_SYS_FSL_TBCLK_DIV
298
299 Defines the core time base clock divider ratio compared to the
300 system clock. On most PQ3 devices this is 8, on newer QorIQ
301 devices it can be 16 or 32. The ratio varies from SoC to Soc.
302
Kumar Gala179b1b22011-05-20 00:39:21 -0500303 CONFIG_SYS_FSL_PCIE_COMPAT
304
305 Defines the string to utilize when trying to match PCIe device
306 tree nodes for the given platform.
307
Scott Wood80806962012-08-14 10:14:53 +0000308 CONFIG_SYS_FSL_ERRATUM_A004510
309
310 Enables a workaround for erratum A004510. If set,
311 then CONFIG_SYS_FSL_ERRATUM_A004510_SVR_REV and
312 CONFIG_SYS_FSL_CORENET_SNOOPVEC_COREONLY must be set.
313
314 CONFIG_SYS_FSL_ERRATUM_A004510_SVR_REV
315 CONFIG_SYS_FSL_ERRATUM_A004510_SVR_REV2 (optional)
316
317 Defines one or two SoC revisions (low 8 bits of SVR)
318 for which the A004510 workaround should be applied.
319
320 The rest of SVR is either not relevant to the decision
321 of whether the erratum is present (e.g. p2040 versus
322 p2041) or is implied by the build target, which controls
323 whether CONFIG_SYS_FSL_ERRATUM_A004510 is set.
324
325 See Freescale App Note 4493 for more information about
326 this erratum.
327
328 CONFIG_SYS_FSL_CORENET_SNOOPVEC_COREONLY
329
330 This is the value to write into CCSR offset 0x18600
331 according to the A004510 workaround.
332
Priyanka Jainc73b9032013-07-02 09:21:04 +0530333 CONFIG_SYS_FSL_DSP_DDR_ADDR
334 This value denotes start offset of DDR memory which is
335 connected exclusively to the DSP cores.
336
Priyanka Jainf81e8b22013-04-04 09:31:54 +0530337 CONFIG_SYS_FSL_DSP_M2_RAM_ADDR
338 This value denotes start offset of M2 memory
339 which is directly connected to the DSP core.
340
Priyanka Jainc73b9032013-07-02 09:21:04 +0530341 CONFIG_SYS_FSL_DSP_M3_RAM_ADDR
342 This value denotes start offset of M3 memory which is directly
343 connected to the DSP core.
344
Priyanka Jainf81e8b22013-04-04 09:31:54 +0530345 CONFIG_SYS_FSL_DSP_CCSRBAR_DEFAULT
346 This value denotes start offset of DSP CCSR space.
347
Priyanka Jaine9dcaa82013-12-17 14:25:52 +0530348 CONFIG_SYS_FSL_SINGLE_SOURCE_CLK
349 Single Source Clock is clocking mode present in some of FSL SoC's.
350 In this mode, a single differential clock is used to supply
351 clocks to the sysclock, ddrclock and usbclock.
352
Daniel Schwierzeckd8a49ca2012-04-02 02:57:56 +0000353- Generic CPU options:
354 CONFIG_SYS_BIG_ENDIAN, CONFIG_SYS_LITTLE_ENDIAN
355
356 Defines the endianess of the CPU. Implementation of those
357 values is arch specific.
358
York Sunf0626592013-09-30 09:22:09 -0700359 CONFIG_SYS_FSL_DDR
360 Freescale DDR driver in use. This type of DDR controller is
Tom Rinie5404982021-05-14 21:34:26 -0400361 found in mpc83xx, mpc85xx as well as some ARM core SoCs.
York Sunf0626592013-09-30 09:22:09 -0700362
363 CONFIG_SYS_FSL_DDR_ADDR
364 Freescale DDR memory-mapped register base.
365
Prabhakar Kushwaha3c48f582017-02-02 15:01:26 +0530366 CONFIG_SYS_FSL_IFC_CLK_DIV
367 Defines divider of platform clock(clock input to IFC controller).
368
Prabhakar Kushwahabedc5622017-02-02 15:02:00 +0530369 CONFIG_SYS_FSL_LBC_CLK_DIV
370 Defines divider of platform clock(clock input to eLBC controller).
371
York Sun3a0916d2014-02-10 13:59:43 -0800372 CONFIG_SYS_FSL_DDR_SDRAM_BASE_PHY
373 Physical address from the view of DDR controllers. It is the
374 same as CONFIG_SYS_DDR_SDRAM_BASE for all Power SoCs. But
375 it could be different for ARM SoCs.
376
Daniel Schwierzeckd52a6232011-07-27 13:22:39 +0200377- MIPS CPU options:
Daniel Schwierzeckd52a6232011-07-27 13:22:39 +0200378 CONFIG_XWAY_SWAP_BYTES
379
380 Enable compilation of tools/xway-swap-bytes needed for Lantiq
381 XWAY SoCs for booting from NOR flash. The U-Boot image needs to
382 be swapped if a flash programmer is used.
383
Christian Riesch48c2d6d2012-02-02 00:44:39 +0000384- ARM options:
385 CONFIG_SYS_EXCEPTION_VECTORS_HIGH
386
387 Select high exception vectors of the ARM core, e.g., do not
388 clear the V bit of the c1 register of CP15.
389
York Sun77a10972015-03-20 19:28:08 -0700390 COUNTER_FREQUENCY
391 Generic timer clock source frequency.
392
393 COUNTER_FREQUENCY_REAL
394 Generic timer clock source frequency if the real clock is
395 different from COUNTER_FREQUENCY, and can only be determined
396 at run time.
397
Stephen Warren8d1fb312015-01-19 16:25:52 -0700398- Tegra SoC options:
399 CONFIG_TEGRA_SUPPORT_NON_SECURE
400
401 Support executing U-Boot in non-secure (NS) mode. Certain
402 impossible actions will be skipped if the CPU is in NS mode,
403 such as ARM architectural timer initialization.
404
wdenk9b7f3842003-10-09 20:09:04 +0000405- Linux Kernel Interface:
wdenk9b7f3842003-10-09 20:09:04 +0000406 CONFIG_MEMSIZE_IN_BYTES [relevant for MIPS only]
407
Jeremiah Mahler03f930c2015-01-04 18:56:50 -0800408 When transferring memsize parameter to Linux, some versions
wdenk9b7f3842003-10-09 20:09:04 +0000409 expect it to be in bytes, others in MB.
410 Define CONFIG_MEMSIZE_IN_BYTES to make it in bytes.
411
Gerald Van Barenfcd91bb2008-06-03 20:34:45 -0400412 CONFIG_OF_LIBFDT
Wolfgang Denk27a5b0b2005-10-13 01:45:54 +0200413
414 New kernel versions are expecting firmware settings to be
Gerald Van Barend6abef42007-03-31 12:23:51 -0400415 passed using flattened device trees (based on open firmware
416 concepts).
417
418 CONFIG_OF_LIBFDT
419 * New libfdt-based support
420 * Adds the "fdt" command
Kim Phillips9b46eb62007-08-10 14:34:14 -0500421 * The bootm command automatically updates the fdt
Gerald Van Barend6abef42007-03-31 12:23:51 -0400422
Wolfgang Denk27a5b0b2005-10-13 01:45:54 +0200423 OF_TBCLK - The timebase frequency.
424
Marcel Ziswilerabd8dcb2008-07-09 08:17:15 +0200425 boards with QUICC Engines require OF_QE to set UCC MAC
426 addresses
Kim Phillips9b46eb62007-08-10 14:34:14 -0500427
Heiko Schocherffb293a2009-09-23 07:56:08 +0200428 CONFIG_OF_IDE_FIXUP
429
430 U-Boot can detect if an IDE device is present or not.
431 If not, and this new config option is activated, U-Boot
432 removes the ATA node from the DTS before booting Linux,
433 so the Linux IDE driver does not probe the device and
434 crash. This is needed for buggy hardware (uc101) where
435 no pull down resistor is connected to the signal IDE5V_DD7.
436
Niklaus Giger0ab978d2008-11-03 22:13:47 +0100437- vxWorks boot parameters:
438
439 bootvx constructs a valid bootline using the following
Bin Mengfb694b92015-10-07 20:19:17 -0700440 environments variables: bootdev, bootfile, ipaddr, netmask,
441 serverip, gatewayip, hostname, othbootargs.
Niklaus Giger0ab978d2008-11-03 22:13:47 +0100442 It loads the vxWorks image pointed bootfile.
443
Naoki Hayama158c2262020-10-08 13:17:08 +0900444 Note: If a "bootargs" environment is defined, it will override
Niklaus Giger0ab978d2008-11-03 22:13:47 +0100445 the defaults discussed just above.
446
Aneesh V686a0752011-06-16 23:30:51 +0000447- Cache Configuration for ARM:
448 CONFIG_SYS_L2_PL310 - Enable support for ARM PL310 L2 cache
449 controller
450 CONFIG_SYS_PL310_BASE - Physical base address of PL310
451 controller register space
452
wdenkda04a8b2004-08-02 23:22:59 +0000453- Serial Ports:
wdenkda04a8b2004-08-02 23:22:59 +0000454 CONFIG_PL011_CLOCK
455
456 If you have Amba PrimeCell PL011 UARTs, set this variable to
457 the clock speed of the UARTs.
458
459 CONFIG_PL01x_PORTS
460
461 If you have Amba PrimeCell PL010 or PL011 UARTs on your board,
462 define this to a list of base addresses for each (supported)
463 port. See e.g. include/configs/versatile.h
464
Karicheri, Muralidharancbc08882014-04-09 15:38:46 -0400465 CONFIG_SERIAL_HW_FLOW_CONTROL
466
467 Define this variable to enable hw flow control in serial driver.
468 Current user of this option is drivers/serial/nsl16550.c driver
wdenkda04a8b2004-08-02 23:22:59 +0000469
wdenkc6097192002-11-03 00:24:07 +0000470- Serial Download Echo Mode:
471 CONFIG_LOADS_ECHO
472 If defined to 1, all characters received during a
473 serial download (using the "loads" command) are
474 echoed back. This might be needed by some terminal
475 emulations (like "cu"), but may as well just take
476 time on others. This setting #define's the initial
477 value of the "loads_echo" environment variable.
478
Simon Glassaa34ef22016-03-13 19:07:28 -0600479- Removal of commands
480 If no commands are needed to boot, you can disable
481 CONFIG_CMDLINE to remove them. In this case, the command line
482 will not be available, and when U-Boot wants to execute the
483 boot command (on start-up) it will call board_run_command()
484 instead. This can reduce image size significantly for very
485 simple boot procedures.
486
Wolfgang Denk2aceea12013-03-23 23:50:31 +0000487- Regular expression support:
488 CONFIG_REGEX
Wolfgang Denkec7fbf52013-10-04 17:43:24 +0200489 If this variable is defined, U-Boot is linked against
490 the SLRE (Super Light Regular Expression) library,
491 which adds regex support to some commands, as for
492 example "env grep" and "setexpr".
Wolfgang Denk2aceea12013-03-23 23:50:31 +0000493
wdenkc6097192002-11-03 00:24:07 +0000494- Watchdog:
Rasmus Villemoes134cc2b2021-04-14 09:18:22 +0200495 CONFIG_SYS_WATCHDOG_FREQ
496 Some platforms automatically call WATCHDOG_RESET()
497 from the timer interrupt handler every
498 CONFIG_SYS_WATCHDOG_FREQ interrupts. If not set by the
499 board configuration file, a default of CONFIG_SYS_HZ/2
500 (i.e. 500) is used. Setting CONFIG_SYS_WATCHDOG_FREQ
501 to 0 disables calling WATCHDOG_RESET() from the timer
502 interrupt.
503
wdenkc6097192002-11-03 00:24:07 +0000504- Real-Time Clock:
505
Jon Loeligerc1da5c92007-06-11 19:03:39 -0500506 When CONFIG_CMD_DATE is selected, the type of the RTC
wdenkc6097192002-11-03 00:24:07 +0000507 has to be selected, too. Define exactly one of the
508 following options:
509
wdenkc6097192002-11-03 00:24:07 +0000510 CONFIG_RTC_PCF8563 - use Philips PCF8563 RTC
Fabio Estevam3f8d1782011-10-24 06:44:15 +0000511 CONFIG_RTC_MC13XXX - use MC13783 or MC13892 RTC
wdenkc6097192002-11-03 00:24:07 +0000512 CONFIG_RTC_MC146818 - use MC146818 RTC
wdenk1fe2c702003-03-06 21:55:29 +0000513 CONFIG_RTC_DS1307 - use Maxim, Inc. DS1307 RTC
wdenkc6097192002-11-03 00:24:07 +0000514 CONFIG_RTC_DS1337 - use Maxim, Inc. DS1337 RTC
wdenk0893c472003-05-20 14:25:27 +0000515 CONFIG_RTC_DS1338 - use Maxim, Inc. DS1338 RTC
Markus Niebel90491f22014-07-21 11:06:16 +0200516 CONFIG_RTC_DS1339 - use Maxim, Inc. DS1339 RTC
wdenkef5fe752003-03-12 10:41:04 +0000517 CONFIG_RTC_DS164x - use Dallas DS164x RTC
Tor Krillb27939b2008-03-15 15:40:26 +0100518 CONFIG_RTC_ISL1208 - use Intersil ISL1208 RTC
wdenkaeba06f2004-06-09 17:34:58 +0000519 CONFIG_RTC_MAX6900 - use Maxim, Inc. MAX6900 RTC
Chris Packham2d3ac512017-05-30 12:03:33 +1200520 CONFIG_RTC_DS1337_NOOSC - Turn off the OSC output for DS1337
Heiko Schocher1f1b7012011-03-28 09:24:22 +0200521 CONFIG_SYS_RV3029_TCR - enable trickle charger on
522 RV3029 RTC.
wdenkc6097192002-11-03 00:24:07 +0000523
wdenkb9bbd242003-06-30 16:24:52 +0000524 Note that if the RTC uses I2C, then the I2C interface
525 must also be configured. See I2C Support, below.
526
Peter Tyser9902e422008-12-17 16:36:21 -0600527- GPIO Support:
528 CONFIG_PCA953X - use NXP's PCA953X series I2C GPIO
Peter Tyser9902e422008-12-17 16:36:21 -0600529
Chris Packham9b383202010-12-19 10:12:13 +0000530 The CONFIG_SYS_I2C_PCA953X_WIDTH option specifies a list of
531 chip-ngpio pairs that tell the PCA953X driver the number of
532 pins supported by a particular chip.
533
Peter Tyser9902e422008-12-17 16:36:21 -0600534 Note that if the GPIO device uses I2C, then the I2C interface
535 must also be configured. See I2C Support, below.
536
Simon Glass4dc47ca2014-06-11 23:29:41 -0600537- I/O tracing:
538 When CONFIG_IO_TRACE is selected, U-Boot intercepts all I/O
539 accesses and can checksum them or write a list of them out
540 to memory. See the 'iotrace' command for details. This is
541 useful for testing device drivers since it can confirm that
542 the driver behaves the same way before and after a code
543 change. Currently this is supported on sandbox and arm. To
544 add support for your architecture, add '#include <iotrace.h>'
545 to the bottom of arch/<arch>/include/asm/io.h and test.
546
547 Example output from the 'iotrace stats' command is below.
548 Note that if the trace buffer is exhausted, the checksum will
549 still continue to operate.
550
551 iotrace is enabled
552 Start: 10000000 (buffer start address)
553 Size: 00010000 (buffer size)
554 Offset: 00000120 (current buffer offset)
555 Output: 10000120 (start + offset)
556 Count: 00000018 (number of trace records)
557 CRC32: 9526fb66 (CRC32 of all trace records)
558
wdenkc6097192002-11-03 00:24:07 +0000559- Timestamp Support:
560
wdenk4a5c8a72003-03-06 00:02:04 +0000561 When CONFIG_TIMESTAMP is selected, the timestamp
562 (date and time) of an image is printed by image
563 commands like bootm or iminfo. This option is
Jon Loeligerc1da5c92007-06-11 19:03:39 -0500564 automatically enabled when you select CONFIG_CMD_DATE .
wdenkc6097192002-11-03 00:24:07 +0000565
Karl O. Pinc8b1f90a2012-08-16 06:20:15 +0000566- Partition Labels (disklabels) Supported:
567 Zero or more of the following:
568 CONFIG_MAC_PARTITION Apple's MacOS partition table.
Karl O. Pinc8b1f90a2012-08-16 06:20:15 +0000569 CONFIG_ISO_PARTITION ISO partition table, used on CDROM etc.
570 CONFIG_EFI_PARTITION GPT partition table, common when EFI is the
571 bootloader. Note 2TB partition limit; see
572 disk/part_efi.c
Simon Glass8706b812016-05-01 11:36:02 -0600573 CONFIG_SCSI) you must configure support for at
Karl O. Pinc8b1f90a2012-08-16 06:20:15 +0000574 least one non-MTD partition type as well.
wdenkc6097192002-11-03 00:24:07 +0000575
wdenkc6097192002-11-03 00:24:07 +0000576- NETWORK Support (PCI):
Kyle Moffett64b94dd2011-10-18 11:05:29 +0000577 CONFIG_E1000_SPI
578 Utility code for direct access to the SPI bus on Intel 8257x.
579 This does not do anything useful unless you set at least one
580 of CONFIG_CMD_E1000 or CONFIG_E1000_SPI_GENERIC.
581
wdenkc6097192002-11-03 00:24:07 +0000582 CONFIG_NATSEMI
583 Support for National dp83815 chips.
584
585 CONFIG_NS8382X
586 Support for National dp8382[01] gigabit chips.
587
wdenkaa603362003-05-12 21:50:16 +0000588- NETWORK Support (other):
Rob Herringc9830dc2011-12-15 11:15:49 +0000589 CONFIG_CALXEDA_XGMAC
590 Support for the Calxeda XGMAC device
591
Ashok93fb8722012-10-15 06:20:47 +0000592 CONFIG_LAN91C96
wdenkaa603362003-05-12 21:50:16 +0000593 Support for SMSC's LAN91C96 chips.
594
wdenkaa603362003-05-12 21:50:16 +0000595 CONFIG_LAN91C96_USE_32_BIT
596 Define this to enable 32 bit addressing
597
Ashok93fb8722012-10-15 06:20:47 +0000598 CONFIG_SMC91111
wdenk3c711762004-06-09 13:37:52 +0000599 Support for SMSC's LAN91C111 chip
600
601 CONFIG_SMC91111_BASE
602 Define this to hold the physical address
603 of the device (I/O space)
604
605 CONFIG_SMC_USE_32_BIT
606 Define this if data bus is 32 bits
607
608 CONFIG_SMC_USE_IOFUNCS
609 Define this to use i/o functions instead of macros
610 (some hardware wont work with macros)
611
Heiko Schocher7d037f72011-11-15 10:00:04 -0500612 CONFIG_SYS_DAVINCI_EMAC_PHY_COUNT
613 Define this if you have more then 3 PHYs.
614
Macpaul Lin199c6252010-12-21 16:59:46 +0800615 CONFIG_FTGMAC100
616 Support for Faraday's FTGMAC100 Gigabit SoC Ethernet
617
618 CONFIG_FTGMAC100_EGIGA
619 Define this to use GE link update with gigabit PHY.
620 Define this if FTGMAC100 is connected to gigabit PHY.
621 If your system has 10/100 PHY only, it might not occur
622 wrong behavior. Because PHY usually return timeout or
623 useless data when polling gigabit status and gigabit
624 control registers. This behavior won't affect the
625 correctnessof 10/100 link speed update.
626
Yoshihiro Shimodaed4cea02011-01-27 10:06:03 +0900627 CONFIG_SH_ETHER
628 Support for Renesas on-chip Ethernet controller
629
630 CONFIG_SH_ETHER_USE_PORT
631 Define the number of ports to be used
632
633 CONFIG_SH_ETHER_PHY_ADDR
634 Define the ETH PHY's address
635
Yoshihiro Shimoda281aa052011-01-27 10:06:08 +0900636 CONFIG_SH_ETHER_CACHE_WRITEBACK
637 If this option is set, the driver enables cache flush.
638
Vadim Bendeburydac69642011-10-17 08:36:14 +0000639- TPM Support:
Che-liang Chiouacea5702013-04-12 11:04:34 +0000640 CONFIG_TPM
641 Support TPM devices.
642
Christophe Ricard8759ff82015-10-06 22:54:41 +0200643 CONFIG_TPM_TIS_INFINEON
644 Support for Infineon i2c bus TPM devices. Only one device
Tom Wai-Hong Tame49fed52013-04-12 11:04:37 +0000645 per system is supported at this time.
646
Tom Wai-Hong Tame49fed52013-04-12 11:04:37 +0000647 CONFIG_TPM_TIS_I2C_BURST_LIMITATION
648 Define the burst count bytes upper limit
649
Christophe Ricard88249232016-01-21 23:27:13 +0100650 CONFIG_TPM_ST33ZP24
651 Support for STMicroelectronics TPM devices. Requires DM_TPM support.
652
653 CONFIG_TPM_ST33ZP24_I2C
654 Support for STMicroelectronics ST33ZP24 I2C devices.
655 Requires TPM_ST33ZP24 and I2C.
656
Christophe Ricard5ffadc32016-01-21 23:27:14 +0100657 CONFIG_TPM_ST33ZP24_SPI
658 Support for STMicroelectronics ST33ZP24 SPI devices.
659 Requires TPM_ST33ZP24 and SPI.
660
Dirk Eibach20489092013-06-26 15:55:15 +0200661 CONFIG_TPM_ATMEL_TWI
662 Support for Atmel TWI TPM device. Requires I2C support.
663
Che-liang Chiouacea5702013-04-12 11:04:34 +0000664 CONFIG_TPM_TIS_LPC
Vadim Bendeburydac69642011-10-17 08:36:14 +0000665 Support for generic parallel port TPM devices. Only one device
666 per system is supported at this time.
667
668 CONFIG_TPM_TIS_BASE_ADDRESS
669 Base address where the generic TPM device is mapped
670 to. Contemporary x86 systems usually map it at
671 0xfed40000.
672
Reinhard Pfau4fece432013-06-26 15:55:13 +0200673 CONFIG_TPM
674 Define this to enable the TPM support library which provides
675 functional interfaces to some TPM commands.
676 Requires support for a TPM device.
677
678 CONFIG_TPM_AUTH_SESSIONS
679 Define this to enable authorized functions in the TPM library.
680 Requires CONFIG_TPM and CONFIG_SHA1.
681
wdenkc6097192002-11-03 00:24:07 +0000682- USB Support:
683 At the moment only the UHCI host controller is
Heiko Schocher6f90e582017-06-14 05:49:40 +0200684 supported (PIP405, MIP405); define
wdenkc6097192002-11-03 00:24:07 +0000685 CONFIG_USB_UHCI to enable it.
686 define CONFIG_USB_KEYBOARD to enable the USB Keyboard
wdenkfb30b4c2004-10-09 22:44:59 +0000687 and define CONFIG_USB_STORAGE to enable the USB
wdenkc6097192002-11-03 00:24:07 +0000688 storage devices.
689 Note:
690 Supported are USB Keyboards and USB Floppy drives
691 (TEAC FD-05PUB).
wdenk369d43d2004-03-14 14:09:05 +0000692
Oleksandr Tymoshenko7a881752014-02-01 21:51:25 -0700693 CONFIG_USB_DWC2_REG_ADDR the physical CPU address of the DWC2
694 HW module registers.
695
Wolfgang Denk3f0137b2006-06-14 17:45:53 +0200696- USB Device:
697 Define the below if you wish to use the USB console.
698 Once firmware is rebuilt from a serial console issue the
699 command "setenv stdin usbtty; setenv stdout usbtty" and
Marcel Ziswilerabd8dcb2008-07-09 08:17:15 +0200700 attach your USB cable. The Unix command "dmesg" should print
Wolfgang Denk3f0137b2006-06-14 17:45:53 +0200701 it has found a new device. The environment variable usbtty
702 can be set to gserial or cdc_acm to enable your device to
Wolfgang Denke2601822006-06-14 18:14:56 +0200703 appear to a USB host as a Linux gserial device or a
Wolfgang Denk3f0137b2006-06-14 17:45:53 +0200704 Common Device Class Abstract Control Model serial device.
705 If you select usbtty = gserial you should be able to enumerate
706 a Linux host by
707 # modprobe usbserial vendor=0xVendorID product=0xProductID
708 else if using cdc_acm, simply setting the environment
709 variable usbtty to be cdc_acm should suffice. The following
710 might be defined in YourBoardName.h
Wolfgang Denke2601822006-06-14 18:14:56 +0200711
Wolfgang Denk3f0137b2006-06-14 17:45:53 +0200712 CONFIG_USB_DEVICE
713 Define this to build a UDC device
714
715 CONFIG_USB_TTY
716 Define this to have a tty type of device available to
717 talk to the UDC device
Wolfgang Denke2601822006-06-14 18:14:56 +0200718
Vipin KUMARbdb17702012-03-26 15:38:06 +0530719 CONFIG_USBD_HS
720 Define this to enable the high speed support for usb
721 device and usbtty. If this feature is enabled, a routine
722 int is_usbd_high_speed(void)
723 also needs to be defined by the driver to dynamically poll
724 whether the enumeration has succeded at high speed or full
725 speed.
726
Wolfgang Denke2601822006-06-14 18:14:56 +0200727 If you have a USB-IF assigned VendorID then you may wish to
Wolfgang Denk3f0137b2006-06-14 17:45:53 +0200728 define your own vendor specific values either in BoardName.h
Wolfgang Denke2601822006-06-14 18:14:56 +0200729 or directly in usbd_vendor_info.h. If you don't define
Wolfgang Denk3f0137b2006-06-14 17:45:53 +0200730 CONFIG_USBD_MANUFACTURER, CONFIG_USBD_PRODUCT_NAME,
731 CONFIG_USBD_VENDORID and CONFIG_USBD_PRODUCTID, then U-Boot
732 should pretend to be a Linux device to it's target host.
733
734 CONFIG_USBD_MANUFACTURER
735 Define this string as the name of your company for
736 - CONFIG_USBD_MANUFACTURER "my company"
Wolfgang Denke2601822006-06-14 18:14:56 +0200737
Wolfgang Denk3f0137b2006-06-14 17:45:53 +0200738 CONFIG_USBD_PRODUCT_NAME
739 Define this string as the name of your product
740 - CONFIG_USBD_PRODUCT_NAME "acme usb device"
wdenkc6097192002-11-03 00:24:07 +0000741
Wolfgang Denk3f0137b2006-06-14 17:45:53 +0200742 CONFIG_USBD_VENDORID
743 Define this as your assigned Vendor ID from the USB
744 Implementors Forum. This *must* be a genuine Vendor ID
745 to avoid polluting the USB namespace.
746 - CONFIG_USBD_VENDORID 0xFFFF
Wolfgang Denke2601822006-06-14 18:14:56 +0200747
Wolfgang Denk3f0137b2006-06-14 17:45:53 +0200748 CONFIG_USBD_PRODUCTID
749 Define this as the unique Product ID
750 for your device
751 - CONFIG_USBD_PRODUCTID 0xFFFF
Wolfgang Denke2601822006-06-14 18:14:56 +0200752
Igor Grinbergac5f6ee2011-12-12 12:08:35 +0200753- ULPI Layer Support:
754 The ULPI (UTMI Low Pin (count) Interface) PHYs are supported via
755 the generic ULPI layer. The generic layer accesses the ULPI PHY
756 via the platform viewport, so you need both the genric layer and
757 the viewport enabled. Currently only Chipidea/ARC based
758 viewport is supported.
759 To enable the ULPI layer support, define CONFIG_USB_ULPI and
760 CONFIG_USB_ULPI_VIEWPORT in your board configuration file.
Lucas Stachf31e4112012-10-01 00:44:35 +0200761 If your ULPI phy needs a different reference clock than the
762 standard 24 MHz then you have to define CONFIG_ULPI_REF_CLK to
763 the appropriate value in Hz.
wdenkc6097192002-11-03 00:24:07 +0000764
wdenk7a428cc2003-06-15 22:40:42 +0000765- MMC Support:
Yoshihiro Shimodadb7717b2011-07-04 22:21:22 +0000766 CONFIG_SH_MMCIF
767 Support for Renesas on-chip MMCIF controller
768
769 CONFIG_SH_MMCIF_ADDR
770 Define the base address of MMCIF registers
771
772 CONFIG_SH_MMCIF_CLK
773 Define the clock frequency for MMCIF
774
Tom Rini58a8d322013-03-14 05:32:47 +0000775- USB Device Firmware Update (DFU) class support:
Marek Vasut7f8d4362018-02-16 16:41:18 +0100776 CONFIG_DFU_OVER_USB
Tom Rini58a8d322013-03-14 05:32:47 +0000777 This enables the USB portion of the DFU USB class
778
Pantelis Antonioucf14d0d2013-03-14 05:32:52 +0000779 CONFIG_DFU_NAND
780 This enables support for exposing NAND devices via DFU.
781
Afzal Mohammede3c687a2013-09-18 01:15:24 +0530782 CONFIG_DFU_RAM
783 This enables support for exposing RAM via DFU.
784 Note: DFU spec refer to non-volatile memory usage, but
785 allow usages beyond the scope of spec - here RAM usage,
786 one that would help mostly the developer.
787
Heiko Schochera2f831e2013-06-12 06:05:51 +0200788 CONFIG_SYS_DFU_DATA_BUF_SIZE
789 Dfu transfer uses a buffer before writing data to the
790 raw storage device. Make the size (in bytes) of this buffer
791 configurable. The size of this buffer is also configurable
792 through the "dfu_bufsiz" environment variable.
793
Pantelis Antonioua6e788d2013-03-14 05:32:48 +0000794 CONFIG_SYS_DFU_MAX_FILE_SIZE
795 When updating files rather than the raw storage device,
796 we use a static buffer to copy the file into and then write
797 the buffer once we've been given the whole file. Define
798 this to the maximum filesize (in bytes) for the buffer.
799 Default is 4 MiB if undefined.
800
Heiko Schochere1ba1512014-03-18 08:09:56 +0100801 DFU_DEFAULT_POLL_TIMEOUT
802 Poll timeout [ms], is the timeout a device can send to the
803 host. The host must wait for this timeout before sending
804 a subsequent DFU_GET_STATUS request to the device.
805
806 DFU_MANIFEST_POLL_TIMEOUT
807 Poll timeout [ms], which the device sends to the host when
808 entering dfuMANIFEST state. Host waits this timeout, before
809 sending again an USB request to the device.
810
wdenkda04a8b2004-08-02 23:22:59 +0000811- Journaling Flash filesystem support:
Jean-Christophe PLAGNIOL-VILLARD03836942008-10-16 15:01:15 +0200812 CONFIG_SYS_JFFS2_FIRST_SECTOR,
813 CONFIG_SYS_JFFS2_FIRST_BANK, CONFIG_SYS_JFFS2_NUM_BANKS
wdenkda04a8b2004-08-02 23:22:59 +0000814 Define these for a default partition on a NOR device
815
wdenkc6097192002-11-03 00:24:07 +0000816- Keyboard Support:
Simon Glasseaba37e2015-11-11 10:05:47 -0700817 See Kconfig help for available keyboard drivers.
818
wdenkc6097192002-11-03 00:24:07 +0000819- LCD Support: CONFIG_LCD
820
821 Define this to enable LCD support (for output to LCD
822 display); also select one of the supported displays
823 by defining one of these:
824
wdenkc0d54ae2003-11-25 16:55:19 +0000825 CONFIG_NEC_NL6448AC33:
wdenkc6097192002-11-03 00:24:07 +0000826
wdenkc0d54ae2003-11-25 16:55:19 +0000827 NEC NL6448AC33-18. Active, color, single scan.
wdenkc6097192002-11-03 00:24:07 +0000828
wdenkc0d54ae2003-11-25 16:55:19 +0000829 CONFIG_NEC_NL6448BC20
830
831 NEC NL6448BC20-08. 6.5", 640x480.
832 Active, color, single scan.
833
834 CONFIG_NEC_NL6448BC33_54
wdenkc6097192002-11-03 00:24:07 +0000835
wdenkc0d54ae2003-11-25 16:55:19 +0000836 NEC NL6448BC33-54. 10.4", 640x480.
wdenkc6097192002-11-03 00:24:07 +0000837 Active, color, single scan.
838
839 CONFIG_SHARP_16x9
840
841 Sharp 320x240. Active, color, single scan.
842 It isn't 16x9, and I am not sure what it is.
843
844 CONFIG_SHARP_LQ64D341
845
846 Sharp LQ64D341 display, 640x480.
847 Active, color, single scan.
848
849 CONFIG_HLD1045
850
851 HLD1045 display, 640x480.
852 Active, color, single scan.
853
854 CONFIG_OPTREX_BW
855
856 Optrex CBL50840-2 NF-FW 99 22 M5
857 or
858 Hitachi LMG6912RPFC-00T
859 or
860 Hitachi SP14Q002
861
862 320x240. Black & white.
863
Simon Glass599a4df2012-10-17 13:24:54 +0000864 CONFIG_LCD_ALIGNMENT
865
Jeremiah Mahler03f930c2015-01-04 18:56:50 -0800866 Normally the LCD is page-aligned (typically 4KB). If this is
Simon Glass599a4df2012-10-17 13:24:54 +0000867 defined then the LCD will be aligned to this value instead.
868 For ARM it is sometimes useful to use MMU_SECTION_SIZE
869 here, since it is cheaper to change data cache settings on
870 a per-section basis.
871
872
Hannes Petermaiera3c8e862015-03-27 08:01:38 +0100873 CONFIG_LCD_ROTATION
874
875 Sometimes, for example if the display is mounted in portrait
876 mode or even if it's mounted landscape but rotated by 180degree,
877 we need to rotate our content of the display relative to the
878 framebuffer, so that user can read the messages which are
879 printed out.
880 Once CONFIG_LCD_ROTATION is defined, the lcd_console will be
881 initialized with a given rotation from "vl_rot" out of
882 "vidinfo_t" which is provided by the board specific code.
883 The value for vl_rot is coded as following (matching to
884 fbcon=rotate:<n> linux-kernel commandline):
885 0 = no rotation respectively 0 degree
886 1 = 90 degree rotation
887 2 = 180 degree rotation
888 3 = 270 degree rotation
889
890 If CONFIG_LCD_ROTATION is not defined, the console will be
891 initialized with 0degree rotation.
892
wdenk0e2bd9c2004-06-06 21:51:03 +0000893- MII/PHY support:
wdenk0e2bd9c2004-06-06 21:51:03 +0000894 CONFIG_PHY_CLOCK_FREQ (ppc4xx)
895
896 The clock frequency of the MII bus
897
wdenk0e2bd9c2004-06-06 21:51:03 +0000898 CONFIG_PHY_CMD_DELAY (ppc4xx)
899
900 Some PHY like Intel LXT971A need extra delay after
901 command issued before MII status register can be read
902
wdenkc6097192002-11-03 00:24:07 +0000903- IP address:
904 CONFIG_IPADDR
905
906 Define a default value for the IP address to use for
Marcel Ziswilerabd8dcb2008-07-09 08:17:15 +0200907 the default Ethernet interface, in case this is not
wdenkc6097192002-11-03 00:24:07 +0000908 determined through e.g. bootp.
Wolfgang Denk26da2992011-10-26 10:21:22 +0000909 (Environment variable "ipaddr")
wdenkc6097192002-11-03 00:24:07 +0000910
911- Server IP address:
912 CONFIG_SERVERIP
913
Marcel Ziswilerabd8dcb2008-07-09 08:17:15 +0200914 Defines a default value for the IP address of a TFTP
wdenkc6097192002-11-03 00:24:07 +0000915 server to contact when using the "tftboot" command.
Wolfgang Denk26da2992011-10-26 10:21:22 +0000916 (Environment variable "serverip")
wdenkc6097192002-11-03 00:24:07 +0000917
Wolfgang Denk26da2992011-10-26 10:21:22 +0000918- Gateway IP address:
919 CONFIG_GATEWAYIP
920
921 Defines a default value for the IP address of the
922 default router where packets to other networks are
923 sent to.
924 (Environment variable "gatewayip")
925
926- Subnet mask:
927 CONFIG_NETMASK
928
929 Defines a default value for the subnet mask (or
930 routing prefix) which is used to determine if an IP
931 address belongs to the local subnet or needs to be
932 forwarded through a router.
933 (Environment variable "netmask")
934
wdenkc6097192002-11-03 00:24:07 +0000935- BOOTP Recovery Mode:
936 CONFIG_BOOTP_RANDOM_DELAY
937
938 If you have many targets in a network that try to
939 boot using BOOTP, you may want to avoid that all
940 systems send out BOOTP requests at precisely the same
941 moment (which would happen for instance at recovery
942 from a power failure, when all systems will try to
943 boot, thus flooding the BOOTP server. Defining
944 CONFIG_BOOTP_RANDOM_DELAY causes a random delay to be
945 inserted before sending out BOOTP requests. The
Wolfgang Denkb65aaf92007-08-06 23:21:05 +0200946 following delays are inserted then:
wdenkc6097192002-11-03 00:24:07 +0000947
948 1st BOOTP request: delay 0 ... 1 sec
949 2nd BOOTP request: delay 0 ... 2 sec
950 3rd BOOTP request: delay 0 ... 4 sec
951 4th and following
952 BOOTP requests: delay 0 ... 8 sec
953
Thierry Reding8977cda2014-08-19 10:21:24 +0200954 CONFIG_BOOTP_ID_CACHE_SIZE
955
956 BOOTP packets are uniquely identified using a 32-bit ID. The
957 server will copy the ID from client requests to responses and
958 U-Boot will use this to determine if it is the destination of
959 an incoming response. Some servers will check that addresses
960 aren't in use before handing them out (usually using an ARP
961 ping) and therefore take up to a few hundred milliseconds to
962 respond. Network congestion may also influence the time it
963 takes for a response to make it back to the client. If that
964 time is too long, U-Boot will retransmit requests. In order
965 to allow earlier responses to still be accepted after these
966 retransmissions, U-Boot's BOOTP client keeps a small cache of
967 IDs. The CONFIG_BOOTP_ID_CACHE_SIZE controls the size of this
968 cache. The default is to keep IDs for up to four outstanding
969 requests. Increasing this will allow U-Boot to accept offers
970 from a BOOTP client in networks with unusually high latency.
971
stroesee0aadfb2003-08-28 14:17:32 +0000972- DHCP Advanced Options:
Joe Hershberger8ca7fa02012-05-23 07:59:19 +0000973
Joe Hershbergerb35a3a62012-05-23 08:00:12 +0000974 - Link-local IP address negotiation:
975 Negotiate with other link-local clients on the local network
976 for an address that doesn't require explicit configuration.
977 This is especially useful if a DHCP server cannot be guaranteed
978 to exist in all environments that the device must operate.
979
980 See doc/README.link-local for more information.
981
Prabhakar Kushwaha2dec06f2017-11-23 16:51:32 +0530982 - MAC address from environment variables
983
984 FDT_SEQ_MACADDR_FROM_ENV
985
986 Fix-up device tree with MAC addresses fetched sequentially from
987 environment variables. This config work on assumption that
988 non-usable ethernet node of device-tree are either not present
989 or their status has been marked as "disabled".
990
wdenk145d2c12004-04-15 21:48:45 +0000991 - CDP Options:
wdenk05939202004-04-18 17:39:38 +0000992 CONFIG_CDP_DEVICE_ID
wdenk145d2c12004-04-15 21:48:45 +0000993
994 The device id used in CDP trigger frames.
995
996 CONFIG_CDP_DEVICE_ID_PREFIX
997
998 A two character string which is prefixed to the MAC address
999 of the device.
1000
1001 CONFIG_CDP_PORT_ID
1002
1003 A printf format string which contains the ascii name of
1004 the port. Normally is set to "eth%d" which sets
Marcel Ziswilerabd8dcb2008-07-09 08:17:15 +02001005 eth0 for the first Ethernet, eth1 for the second etc.
wdenk145d2c12004-04-15 21:48:45 +00001006
1007 CONFIG_CDP_CAPABILITIES
1008
1009 A 32bit integer which indicates the device capabilities;
1010 0x00000010 for a normal host which does not forwards.
1011
1012 CONFIG_CDP_VERSION
1013
1014 An ascii string containing the version of the software.
1015
1016 CONFIG_CDP_PLATFORM
1017
1018 An ascii string containing the name of the platform.
1019
1020 CONFIG_CDP_TRIGGER
1021
1022 A 32bit integer sent on the trigger.
1023
1024 CONFIG_CDP_POWER_CONSUMPTION
1025
1026 A 16bit integer containing the power consumption of the
1027 device in .1 of milliwatts.
1028
1029 CONFIG_CDP_APPLIANCE_VLAN_TYPE
1030
1031 A byte containing the id of the VLAN.
1032
Uri Mashiach3dc6f652017-01-19 10:51:05 +02001033- Status LED: CONFIG_LED_STATUS
wdenkc6097192002-11-03 00:24:07 +00001034
1035 Several configurations allow to display the current
1036 status using a LED. For instance, the LED will blink
1037 fast while running U-Boot code, stop blinking as
1038 soon as a reply to a BOOTP request was received, and
1039 start blinking slow once the Linux kernel is running
1040 (supported by a status LED driver in the Linux
Uri Mashiach3dc6f652017-01-19 10:51:05 +02001041 kernel). Defining CONFIG_LED_STATUS enables this
wdenkc6097192002-11-03 00:24:07 +00001042 feature in U-Boot.
1043
Igor Grinberg4997a9e2013-11-08 01:03:50 +02001044 Additional options:
1045
Uri Mashiach3dc6f652017-01-19 10:51:05 +02001046 CONFIG_LED_STATUS_GPIO
Igor Grinberg4997a9e2013-11-08 01:03:50 +02001047 The status LED can be connected to a GPIO pin.
1048 In such cases, the gpio_led driver can be used as a
Uri Mashiach3dc6f652017-01-19 10:51:05 +02001049 status LED backend implementation. Define CONFIG_LED_STATUS_GPIO
Igor Grinberg4997a9e2013-11-08 01:03:50 +02001050 to include the gpio_led driver in the U-Boot binary.
1051
Igor Grinberg203bd9f2013-11-08 01:03:52 +02001052 CONFIG_GPIO_LED_INVERTED_TABLE
1053 Some GPIO connected LEDs may have inverted polarity in which
1054 case the GPIO high value corresponds to LED off state and
1055 GPIO low value corresponds to LED on state.
1056 In such cases CONFIG_GPIO_LED_INVERTED_TABLE may be defined
1057 with a list of GPIO LEDs that have inverted polarity.
1058
Tom Rini52b2e262021-08-18 23:12:24 -04001059- I2C Support:
Heiko Schochere0e55bc2012-01-16 21:12:24 +00001060 CONFIG_SYS_NUM_I2C_BUSES
Simon Glassb05e2b32016-10-02 18:01:05 -06001061 Hold the number of i2c buses you want to use.
Heiko Schochere0e55bc2012-01-16 21:12:24 +00001062
1063 CONFIG_SYS_I2C_DIRECT_BUS
1064 define this, if you don't use i2c muxes on your hardware.
1065 if CONFIG_SYS_I2C_MAX_HOPS is not defined or == 0 you can
1066 omit this define.
1067
1068 CONFIG_SYS_I2C_MAX_HOPS
1069 define how many muxes are maximal consecutively connected
1070 on one i2c bus. If you not use i2c muxes, omit this
1071 define.
1072
1073 CONFIG_SYS_I2C_BUSES
Jeremiah Mahler03f930c2015-01-04 18:56:50 -08001074 hold a list of buses you want to use, only used if
Heiko Schochere0e55bc2012-01-16 21:12:24 +00001075 CONFIG_SYS_I2C_DIRECT_BUS is not defined, for example
1076 a board with CONFIG_SYS_I2C_MAX_HOPS = 1 and
1077 CONFIG_SYS_NUM_I2C_BUSES = 9:
1078
1079 CONFIG_SYS_I2C_BUSES {{0, {I2C_NULL_HOP}}, \
1080 {0, {{I2C_MUX_PCA9547, 0x70, 1}}}, \
1081 {0, {{I2C_MUX_PCA9547, 0x70, 2}}}, \
1082 {0, {{I2C_MUX_PCA9547, 0x70, 3}}}, \
1083 {0, {{I2C_MUX_PCA9547, 0x70, 4}}}, \
1084 {0, {{I2C_MUX_PCA9547, 0x70, 5}}}, \
1085 {1, {I2C_NULL_HOP}}, \
1086 {1, {{I2C_MUX_PCA9544, 0x72, 1}}}, \
1087 {1, {{I2C_MUX_PCA9544, 0x72, 2}}}, \
1088 }
1089
1090 which defines
1091 bus 0 on adapter 0 without a mux
Heiko Schocher479a4cf2013-01-29 08:53:15 +01001092 bus 1 on adapter 0 with a PCA9547 on address 0x70 port 1
1093 bus 2 on adapter 0 with a PCA9547 on address 0x70 port 2
1094 bus 3 on adapter 0 with a PCA9547 on address 0x70 port 3
1095 bus 4 on adapter 0 with a PCA9547 on address 0x70 port 4
1096 bus 5 on adapter 0 with a PCA9547 on address 0x70 port 5
Heiko Schochere0e55bc2012-01-16 21:12:24 +00001097 bus 6 on adapter 1 without a mux
Heiko Schocher479a4cf2013-01-29 08:53:15 +01001098 bus 7 on adapter 1 with a PCA9544 on address 0x72 port 1
1099 bus 8 on adapter 1 with a PCA9544 on address 0x72 port 2
Heiko Schochere0e55bc2012-01-16 21:12:24 +00001100
1101 If you do not have i2c muxes on your board, omit this define.
1102
Simon Glass3efce392017-05-12 21:10:00 -06001103- Legacy I2C Support:
Heiko Schocher479a4cf2013-01-29 08:53:15 +01001104 If you use the software i2c interface (CONFIG_SYS_I2C_SOFT)
wdenkb9bbd242003-06-30 16:24:52 +00001105 then the following macros need to be defined (examples are
1106 from include/configs/lwmon.h):
wdenkc6097192002-11-03 00:24:07 +00001107
1108 I2C_INIT
1109
wdenkb9bbd242003-06-30 16:24:52 +00001110 (Optional). Any commands necessary to enable the I2C
wdenk4a5c8a72003-03-06 00:02:04 +00001111 controller or configure ports.
wdenkc6097192002-11-03 00:24:07 +00001112
wdenk544e9732004-02-06 23:19:44 +00001113 eg: #define I2C_INIT (immr->im_cpm.cp_pbdir |= PB_SCL)
wdenkb9bbd242003-06-30 16:24:52 +00001114
wdenkc6097192002-11-03 00:24:07 +00001115 I2C_ACTIVE
1116
1117 The code necessary to make the I2C data line active
1118 (driven). If the data line is open collector, this
1119 define can be null.
1120
wdenkb9bbd242003-06-30 16:24:52 +00001121 eg: #define I2C_ACTIVE (immr->im_cpm.cp_pbdir |= PB_SDA)
1122
wdenkc6097192002-11-03 00:24:07 +00001123 I2C_TRISTATE
1124
1125 The code necessary to make the I2C data line tri-stated
1126 (inactive). If the data line is open collector, this
1127 define can be null.
1128
wdenkb9bbd242003-06-30 16:24:52 +00001129 eg: #define I2C_TRISTATE (immr->im_cpm.cp_pbdir &= ~PB_SDA)
1130
wdenkc6097192002-11-03 00:24:07 +00001131 I2C_READ
1132
York Sun4a598092013-04-01 11:29:11 -07001133 Code that returns true if the I2C data line is high,
1134 false if it is low.
wdenkc6097192002-11-03 00:24:07 +00001135
wdenkb9bbd242003-06-30 16:24:52 +00001136 eg: #define I2C_READ ((immr->im_cpm.cp_pbdat & PB_SDA) != 0)
1137
wdenkc6097192002-11-03 00:24:07 +00001138 I2C_SDA(bit)
1139
York Sun4a598092013-04-01 11:29:11 -07001140 If <bit> is true, sets the I2C data line high. If it
1141 is false, it clears it (low).
wdenkc6097192002-11-03 00:24:07 +00001142
wdenkb9bbd242003-06-30 16:24:52 +00001143 eg: #define I2C_SDA(bit) \
wdenk2bb11052003-07-17 23:16:40 +00001144 if(bit) immr->im_cpm.cp_pbdat |= PB_SDA; \
wdenk544e9732004-02-06 23:19:44 +00001145 else immr->im_cpm.cp_pbdat &= ~PB_SDA
wdenkb9bbd242003-06-30 16:24:52 +00001146
wdenkc6097192002-11-03 00:24:07 +00001147 I2C_SCL(bit)
1148
York Sun4a598092013-04-01 11:29:11 -07001149 If <bit> is true, sets the I2C clock line high. If it
1150 is false, it clears it (low).
wdenkc6097192002-11-03 00:24:07 +00001151
wdenkb9bbd242003-06-30 16:24:52 +00001152 eg: #define I2C_SCL(bit) \
wdenk2bb11052003-07-17 23:16:40 +00001153 if(bit) immr->im_cpm.cp_pbdat |= PB_SCL; \
wdenk544e9732004-02-06 23:19:44 +00001154 else immr->im_cpm.cp_pbdat &= ~PB_SCL
wdenkb9bbd242003-06-30 16:24:52 +00001155
wdenkc6097192002-11-03 00:24:07 +00001156 I2C_DELAY
1157
1158 This delay is invoked four times per clock cycle so this
1159 controls the rate of data transfer. The data rate thus
wdenkb9bbd242003-06-30 16:24:52 +00001160 is 1 / (I2C_DELAY * 4). Often defined to be something
wdenk21136db2003-07-16 21:53:01 +00001161 like:
1162
wdenkb9bbd242003-06-30 16:24:52 +00001163 #define I2C_DELAY udelay(2)
wdenkc6097192002-11-03 00:24:07 +00001164
Mike Frysingeree12d542010-07-21 13:38:02 -04001165 CONFIG_SOFT_I2C_GPIO_SCL / CONFIG_SOFT_I2C_GPIO_SDA
1166
1167 If your arch supports the generic GPIO framework (asm/gpio.h),
1168 then you may alternatively define the two GPIOs that are to be
1169 used as SCL / SDA. Any of the previous I2C_xxx macros will
1170 have GPIO-based defaults assigned to them as appropriate.
1171
1172 You should define these to the GPIO value as given directly to
1173 the generic GPIO functions.
1174
Jean-Christophe PLAGNIOL-VILLARD03836942008-10-16 15:01:15 +02001175 CONFIG_SYS_I2C_INIT_BOARD
wdenkcc1e2562003-03-06 13:39:27 +00001176
wdenk57b2d802003-06-27 21:31:46 +00001177 When a board is reset during an i2c bus transfer
1178 chips might think that the current transfer is still
1179 in progress. On some boards it is possible to access
1180 the i2c SCLK line directly, either by using the
1181 processor pin as a GPIO or by having a second pin
1182 connected to the bus. If this option is defined a
1183 custom i2c_init_board() routine in boards/xxx/board.c
1184 is run early in the boot sequence.
wdenkcc1e2562003-03-06 13:39:27 +00001185
Ben Warren45657152006-09-07 16:50:54 -04001186 CONFIG_I2C_MULTI_BUS
1187
1188 This option allows the use of multiple I2C buses, each of which
Wolfgang Denk092ae952011-10-26 10:21:21 +00001189 must have a controller. At any point in time, only one bus is
1190 active. To switch to a different bus, use the 'i2c dev' command.
Ben Warren45657152006-09-07 16:50:54 -04001191 Note that bus numbering is zero-based.
1192
Jean-Christophe PLAGNIOL-VILLARD03836942008-10-16 15:01:15 +02001193 CONFIG_SYS_I2C_NOPROBES
Ben Warren45657152006-09-07 16:50:54 -04001194
1195 This option specifies a list of I2C devices that will be skipped
Wolfgang Denk092ae952011-10-26 10:21:21 +00001196 when the 'i2c probe' command is issued. If CONFIG_I2C_MULTI_BUS
Peter Tyser469cde42009-04-18 22:34:03 -05001197 is set, specify a list of bus-device pairs. Otherwise, specify
1198 a 1D array of device addresses
Ben Warren45657152006-09-07 16:50:54 -04001199
1200 e.g.
1201 #undef CONFIG_I2C_MULTI_BUS
Wolfgang Denk092ae952011-10-26 10:21:21 +00001202 #define CONFIG_SYS_I2C_NOPROBES {0x50,0x68}
Ben Warren45657152006-09-07 16:50:54 -04001203
1204 will skip addresses 0x50 and 0x68 on a board with one I2C bus
1205
Wolfgang Denk092ae952011-10-26 10:21:21 +00001206 #define CONFIG_I2C_MULTI_BUS
Simon Glassb05e2b32016-10-02 18:01:05 -06001207 #define CONFIG_SYS_I2C_NOPROBES {{0,0x50},{0,0x68},{1,0x54}}
Ben Warren45657152006-09-07 16:50:54 -04001208
1209 will skip addresses 0x50 and 0x68 on bus 0 and address 0x54 on bus 1
1210
Jean-Christophe PLAGNIOL-VILLARD03836942008-10-16 15:01:15 +02001211 CONFIG_SYS_RTC_BUS_NUM
Stefan Roese096cc9b2007-02-20 10:51:26 +01001212
1213 If defined, then this indicates the I2C bus number for the RTC.
1214 If not defined, then U-Boot assumes that RTC is on I2C bus 0.
1215
Andrew Dyer58c41f92008-12-29 17:36:01 -06001216 CONFIG_SOFT_I2C_READ_REPEATED_START
1217
1218 defining this will force the i2c_read() function in
1219 the soft_i2c driver to perform an I2C repeated start
1220 between writing the address pointer and reading the
1221 data. If this define is omitted the default behaviour
1222 of doing a stop-start sequence will be used. Most I2C
1223 devices can use either method, but some require one or
1224 the other.
Timur Tabiab347542006-11-03 19:15:00 -06001225
wdenkc6097192002-11-03 00:24:07 +00001226- SPI Support: CONFIG_SPI
1227
1228 Enables SPI driver (so far only tested with
1229 SPI EEPROM, also an instance works with Crystal A/D and
1230 D/As on the SACSng board)
1231
Heiko Schocherb77c8882014-07-14 10:22:11 +02001232 CONFIG_SYS_SPI_MXC_WAIT
1233 Timeout for waiting until spi transfer completed.
1234 default: (CONFIG_SYS_HZ/100) /* 10 ms */
1235
Matthias Fuchsa4400872007-12-27 17:12:34 +01001236- FPGA Support: CONFIG_FPGA
wdenkc6097192002-11-03 00:24:07 +00001237
Matthias Fuchsa4400872007-12-27 17:12:34 +01001238 Enables FPGA subsystem.
1239
1240 CONFIG_FPGA_<vendor>
1241
1242 Enables support for specific chip vendors.
1243 (ALTERA, XILINX)
wdenkc6097192002-11-03 00:24:07 +00001244
Matthias Fuchsa4400872007-12-27 17:12:34 +01001245 CONFIG_FPGA_<family>
wdenkc6097192002-11-03 00:24:07 +00001246
Matthias Fuchsa4400872007-12-27 17:12:34 +01001247 Enables support for FPGA family.
1248 (SPARTAN2, SPARTAN3, VIRTEX2, CYCLONE2, ACEX1K, ACEX)
1249
Jean-Christophe PLAGNIOL-VILLARD03836942008-10-16 15:01:15 +02001250 CONFIG_SYS_FPGA_CHECK_BUSY
wdenkc6097192002-11-03 00:24:07 +00001251
wdenk4a5c8a72003-03-06 00:02:04 +00001252 Enable checks on FPGA configuration interface busy
1253 status by the configuration function. This option
1254 will require a board or device specific function to
1255 be written.
wdenkc6097192002-11-03 00:24:07 +00001256
1257 CONFIG_FPGA_DELAY
1258
1259 If defined, a function that provides delays in the FPGA
1260 configuration driver.
1261
Jean-Christophe PLAGNIOL-VILLARD03836942008-10-16 15:01:15 +02001262 CONFIG_SYS_FPGA_CHECK_ERROR
wdenkc6097192002-11-03 00:24:07 +00001263
wdenk4a5c8a72003-03-06 00:02:04 +00001264 Check for configuration errors during FPGA bitfile
1265 loading. For example, abort during Virtex II
1266 configuration if the INIT_B line goes low (which
1267 indicated a CRC error).
wdenkc6097192002-11-03 00:24:07 +00001268
Jean-Christophe PLAGNIOL-VILLARD03836942008-10-16 15:01:15 +02001269 CONFIG_SYS_FPGA_WAIT_INIT
wdenkc6097192002-11-03 00:24:07 +00001270
Jeremiah Mahler03f930c2015-01-04 18:56:50 -08001271 Maximum time to wait for the INIT_B line to de-assert
1272 after PROB_B has been de-asserted during a Virtex II
wdenk4a5c8a72003-03-06 00:02:04 +00001273 FPGA configuration sequence. The default time is 500
Marcel Ziswilerabd8dcb2008-07-09 08:17:15 +02001274 ms.
wdenkc6097192002-11-03 00:24:07 +00001275
Jean-Christophe PLAGNIOL-VILLARD03836942008-10-16 15:01:15 +02001276 CONFIG_SYS_FPGA_WAIT_BUSY
wdenkc6097192002-11-03 00:24:07 +00001277
Jeremiah Mahler03f930c2015-01-04 18:56:50 -08001278 Maximum time to wait for BUSY to de-assert during
Marcel Ziswilerabd8dcb2008-07-09 08:17:15 +02001279 Virtex II FPGA configuration. The default is 5 ms.
wdenkc6097192002-11-03 00:24:07 +00001280
Jean-Christophe PLAGNIOL-VILLARD03836942008-10-16 15:01:15 +02001281 CONFIG_SYS_FPGA_WAIT_CONFIG
wdenkc6097192002-11-03 00:24:07 +00001282
wdenk4a5c8a72003-03-06 00:02:04 +00001283 Time to wait after FPGA configuration. The default is
Marcel Ziswilerabd8dcb2008-07-09 08:17:15 +02001284 200 ms.
wdenkc6097192002-11-03 00:24:07 +00001285
wdenkc6097192002-11-03 00:24:07 +00001286- Vendor Parameter Protection:
1287
wdenk4a5c8a72003-03-06 00:02:04 +00001288 U-Boot considers the values of the environment
1289 variables "serial#" (Board Serial Number) and
wdenkeb20ad32003-09-05 23:19:14 +00001290 "ethaddr" (Ethernet Address) to be parameters that
wdenk4a5c8a72003-03-06 00:02:04 +00001291 are set once by the board vendor / manufacturer, and
1292 protects these variables from casual modification by
1293 the user. Once set, these variables are read-only,
1294 and write or delete attempts are rejected. You can
Marcel Ziswilerabd8dcb2008-07-09 08:17:15 +02001295 change this behaviour:
wdenkc6097192002-11-03 00:24:07 +00001296
1297 If CONFIG_ENV_OVERWRITE is #defined in your config
1298 file, the write protection for vendor parameters is
wdenkcc1e2562003-03-06 13:39:27 +00001299 completely disabled. Anybody can change or delete
wdenkc6097192002-11-03 00:24:07 +00001300 these parameters.
1301
Joe Hershberger76f353e2015-05-04 14:55:14 -05001302 Alternatively, if you define _both_ an ethaddr in the
1303 default env _and_ CONFIG_OVERWRITE_ETHADDR_ONCE, a default
Marcel Ziswilerabd8dcb2008-07-09 08:17:15 +02001304 Ethernet address is installed in the environment,
wdenkc6097192002-11-03 00:24:07 +00001305 which can be changed exactly ONCE by the user. [The
1306 serial# is unaffected by this, i. e. it remains
1307 read-only.]
1308
Joe Hershberger71497d02012-12-11 22:16:31 -06001309 The same can be accomplished in a more flexible way
1310 for any variable by configuring the type of access
1311 to allow for those variables in the ".flags" variable
1312 or define CONFIG_ENV_FLAGS_LIST_STATIC.
1313
wdenkc6097192002-11-03 00:24:07 +00001314- Protected RAM:
1315 CONFIG_PRAM
1316
1317 Define this variable to enable the reservation of
1318 "protected RAM", i. e. RAM which is not overwritten
1319 by U-Boot. Define CONFIG_PRAM to hold the number of
1320 kB you want to reserve for pRAM. You can overwrite
1321 this default value by defining an environment
1322 variable "pram" to the number of kB you want to
1323 reserve. Note that the board info structure will
1324 still show the full amount of RAM. If pRAM is
1325 reserved, a new environment variable "mem" will
1326 automatically be defined to hold the amount of
1327 remaining RAM in a form that can be passed as boot
1328 argument to Linux, for instance like that:
1329
Wolfgang Denk86eb3b72005-11-20 21:40:11 +01001330 setenv bootargs ... mem=\${mem}
wdenkc6097192002-11-03 00:24:07 +00001331 saveenv
1332
1333 This way you can tell Linux not to use this memory,
1334 either, which results in a memory region that will
1335 not be affected by reboots.
1336
1337 *WARNING* If your board configuration uses automatic
1338 detection of the RAM size, you must make sure that
1339 this memory test is non-destructive. So far, the
1340 following board configurations are known to be
1341 "pRAM-clean":
1342
Heiko Schocher65d94db2017-06-07 17:33:09 +02001343 IVMS8, IVML24, SPD8xx,
Wolfgang Denk90326762012-10-24 02:36:15 +00001344 HERMES, IP860, RPXlite, LWMON,
Heiko Schocher71cb3e92017-06-07 17:33:10 +02001345 FLAGADM
wdenkc6097192002-11-03 00:24:07 +00001346
1347- Error Recovery:
wdenkc6097192002-11-03 00:24:07 +00001348 Note:
1349
wdenk57b2d802003-06-27 21:31:46 +00001350 In the current implementation, the local variables
1351 space and global environment variables space are
1352 separated. Local variables are those you define by
1353 simply typing `name=value'. To access a local
1354 variable later on, you have write `$name' or
1355 `${name}'; to execute the contents of a variable
1356 directly type `$name' at the command prompt.
wdenkc6097192002-11-03 00:24:07 +00001357
wdenk4a5c8a72003-03-06 00:02:04 +00001358 Global environment variables are those you use
1359 setenv/printenv to work with. To run a command stored
1360 in such a variable, you need to use the run command,
1361 and you must not use the '$' sign to access them.
wdenkc6097192002-11-03 00:24:07 +00001362
1363 To store commands and special characters in a
1364 variable, please use double quotation marks
1365 surrounding the whole text of the variable, instead
1366 of the backslashes before semicolons and special
1367 symbols.
1368
wdenkc0aa5c52003-12-06 19:49:23 +00001369- Default Environment:
wdenkc6097192002-11-03 00:24:07 +00001370 CONFIG_EXTRA_ENV_SETTINGS
1371
wdenk4a5c8a72003-03-06 00:02:04 +00001372 Define this to contain any number of null terminated
1373 strings (variable = value pairs) that will be part of
wdenkeb20ad32003-09-05 23:19:14 +00001374 the default environment compiled into the boot image.
wdenk591dda52002-11-18 00:14:45 +00001375
wdenk4a5c8a72003-03-06 00:02:04 +00001376 For example, place something like this in your
1377 board's config file:
wdenkc6097192002-11-03 00:24:07 +00001378
1379 #define CONFIG_EXTRA_ENV_SETTINGS \
1380 "myvar1=value1\0" \
1381 "myvar2=value2\0"
1382
wdenk4a5c8a72003-03-06 00:02:04 +00001383 Warning: This method is based on knowledge about the
1384 internal format how the environment is stored by the
1385 U-Boot code. This is NOT an official, exported
1386 interface! Although it is unlikely that this format
wdenkeb20ad32003-09-05 23:19:14 +00001387 will change soon, there is no guarantee either.
wdenkc6097192002-11-03 00:24:07 +00001388 You better know what you are doing here.
1389
wdenk4a5c8a72003-03-06 00:02:04 +00001390 Note: overly (ab)use of the default environment is
1391 discouraged. Make sure to check other ways to preset
Wolfgang Denk85c25df2009-04-01 23:34:12 +02001392 the environment like the "source" command or the
wdenk4a5c8a72003-03-06 00:02:04 +00001393 boot command first.
wdenkc6097192002-11-03 00:24:07 +00001394
Simon Glass6b8d5fd2012-11-30 13:01:17 +00001395 CONFIG_DELAY_ENVIRONMENT
1396
1397 Normally the environment is loaded when the board is
Jeremiah Mahler03f930c2015-01-04 18:56:50 -08001398 initialised so that it is available to U-Boot. This inhibits
Simon Glass6b8d5fd2012-11-30 13:01:17 +00001399 that so that the environment is not available until
1400 explicitly loaded later by U-Boot code. With CONFIG_OF_CONTROL
1401 this is instead controlled by the value of
1402 /config/load-environment.
1403
Wolfgang Denkd590fb12011-10-07 09:58:21 +02001404 CONFIG_STANDALONE_LOAD_ADDR
1405
Wolfgang Denk23f78482011-10-09 21:06:34 +02001406 This option defines a board specific value for the
1407 address where standalone program gets loaded, thus
1408 overwriting the architecture dependent default
Wolfgang Denkd590fb12011-10-07 09:58:21 +02001409 settings.
1410
Detlev Zundel0ecb6112009-12-01 17:16:19 +01001411- Automatic software updates via TFTP server
1412 CONFIG_UPDATE_TFTP
1413 CONFIG_UPDATE_TFTP_CNT_MAX
1414 CONFIG_UPDATE_TFTP_MSEC_MAX
1415
1416 These options enable and control the auto-update feature;
1417 for a more detailed description refer to doc/README.update.
1418
1419- MTD Support (mtdparts command, UBI support)
Heiko Schocherf5895d12014-06-24 10:10:04 +02001420 CONFIG_MTD_UBI_WL_THRESHOLD
1421 This parameter defines the maximum difference between the highest
1422 erase counter value and the lowest erase counter value of eraseblocks
1423 of UBI devices. When this threshold is exceeded, UBI starts performing
1424 wear leveling by means of moving data from eraseblock with low erase
1425 counter to eraseblocks with high erase counter.
1426
1427 The default value should be OK for SLC NAND flashes, NOR flashes and
1428 other flashes which have eraseblock life-cycle 100000 or more.
1429 However, in case of MLC NAND flashes which typically have eraseblock
1430 life-cycle less than 10000, the threshold should be lessened (e.g.,
1431 to 128 or 256, although it does not have to be power of 2).
1432
1433 default: 4096
Simon Glass6c0be912014-10-23 18:58:54 -06001434
Heiko Schocherf5895d12014-06-24 10:10:04 +02001435 CONFIG_MTD_UBI_BEB_LIMIT
1436 This option specifies the maximum bad physical eraseblocks UBI
1437 expects on the MTD device (per 1024 eraseblocks). If the
1438 underlying flash does not admit of bad eraseblocks (e.g. NOR
1439 flash), this value is ignored.
1440
1441 NAND datasheets often specify the minimum and maximum NVM
1442 (Number of Valid Blocks) for the flashes' endurance lifetime.
1443 The maximum expected bad eraseblocks per 1024 eraseblocks
1444 then can be calculated as "1024 * (1 - MinNVB / MaxNVB)",
1445 which gives 20 for most NANDs (MaxNVB is basically the total
1446 count of eraseblocks on the chip).
1447
1448 To put it differently, if this value is 20, UBI will try to
1449 reserve about 1.9% of physical eraseblocks for bad blocks
1450 handling. And that will be 1.9% of eraseblocks on the entire
1451 NAND chip, not just the MTD partition UBI attaches. This means
1452 that if you have, say, a NAND flash chip admits maximum 40 bad
1453 eraseblocks, and it is split on two MTD partitions of the same
1454 size, UBI will reserve 40 eraseblocks when attaching a
1455 partition.
1456
1457 default: 20
1458
1459 CONFIG_MTD_UBI_FASTMAP
1460 Fastmap is a mechanism which allows attaching an UBI device
1461 in nearly constant time. Instead of scanning the whole MTD device it
1462 only has to locate a checkpoint (called fastmap) on the device.
1463 The on-flash fastmap contains all information needed to attach
1464 the device. Using fastmap makes only sense on large devices where
1465 attaching by scanning takes long. UBI will not automatically install
1466 a fastmap on old images, but you can set the UBI parameter
1467 CONFIG_MTD_UBI_FASTMAP_AUTOCONVERT to 1 if you want so. Please note
1468 that fastmap-enabled images are still usable with UBI implementations
1469 without fastmap support. On typical flash devices the whole fastmap
1470 fits into one PEB. UBI will reserve PEBs to hold two fastmaps.
1471
1472 CONFIG_MTD_UBI_FASTMAP_AUTOCONVERT
1473 Set this parameter to enable fastmap automatically on images
1474 without a fastmap.
1475 default: 0
1476
Heiko Schocher94b66de2015-10-22 06:19:21 +02001477 CONFIG_MTD_UBI_FM_DEBUG
1478 Enable UBI fastmap debug
1479 default: 0
1480
Daniel Schwierzeck39ca08e2011-07-18 07:48:07 +00001481- SPL framework
Wolfgang Denk825223d2011-09-11 21:24:09 +02001482 CONFIG_SPL
1483 Enable building of SPL globally.
Daniel Schwierzeck39ca08e2011-07-18 07:48:07 +00001484
Albert ARIBAUD \(3ADEV\)287b0942015-03-31 11:40:50 +02001485 CONFIG_SPL_PANIC_ON_RAW_IMAGE
1486 When defined, SPL will panic() if the image it has
1487 loaded does not have a signature.
1488 Defining this is useful when code which loads images
1489 in SPL cannot guarantee that absolutely all read errors
1490 will be caught.
1491 An example is the LPC32XX MLC NAND driver, which will
1492 consider that a completely unreadable NAND block is bad,
1493 and thus should be skipped silently.
1494
Tom Rinife3b0c72012-08-13 11:37:56 -07001495 CONFIG_SPL_DISPLAY_PRINT
1496 For ARM, enable an optional function to print more information
1497 about the running system.
1498
Scott Wood2b36fbb2012-12-06 13:33:17 +00001499 CONFIG_SPL_MPC83XX_WAIT_FOR_NAND
1500 Set this for NAND SPL on PPC mpc83xx targets, so that
1501 start.S waits for the rest of the SPL to load before
1502 continuing (the hardware starts execution after just
1503 loading the first page rather than the full 4K).
1504
Thomas Gleixner820d24d2016-07-12 20:28:12 +02001505 CONFIG_SPL_UBI
1506 Support for a lightweight UBI (fastmap) scanner and
1507 loader
1508
Tom Rini36853852012-02-14 07:29:40 +00001509 CONFIG_SYS_NAND_5_ADDR_CYCLE, CONFIG_SYS_NAND_PAGE_COUNT,
1510 CONFIG_SYS_NAND_PAGE_SIZE, CONFIG_SYS_NAND_OOBSIZE,
1511 CONFIG_SYS_NAND_BLOCK_SIZE, CONFIG_SYS_NAND_BAD_BLOCK_POS,
1512 CONFIG_SYS_NAND_ECCPOS, CONFIG_SYS_NAND_ECCSIZE,
1513 CONFIG_SYS_NAND_ECCBYTES
1514 Defines the size and behavior of the NAND that SPL uses
Scott Wood36c440e2012-09-21 18:35:27 -05001515 to read U-Boot
Tom Rini36853852012-02-14 07:29:40 +00001516
Scott Wood36c440e2012-09-21 18:35:27 -05001517 CONFIG_SYS_NAND_U_BOOT_DST
1518 Location in memory to load U-Boot to
1519
1520 CONFIG_SYS_NAND_U_BOOT_SIZE
1521 Size of image to load
Tom Rini36853852012-02-14 07:29:40 +00001522
1523 CONFIG_SYS_NAND_U_BOOT_START
Scott Wood36c440e2012-09-21 18:35:27 -05001524 Entry point in loaded image to jump to
Tom Rini36853852012-02-14 07:29:40 +00001525
1526 CONFIG_SYS_NAND_HW_ECC_OOBFIRST
1527 Define this if you need to first read the OOB and then the
Jeremiah Mahler03f930c2015-01-04 18:56:50 -08001528 data. This is used, for example, on davinci platforms.
Tom Rini36853852012-02-14 07:29:40 +00001529
Pavel Machekde997252012-08-30 22:42:11 +02001530 CONFIG_SPL_RAM_DEVICE
1531 Support for running image already present in ram, in SPL binary
1532
Marek Vasut9f2e0eb2018-05-13 00:22:52 +02001533 CONFIG_SPL_FIT_PRINT
Simon Glass82d94532013-05-08 08:05:59 +00001534 Printing information about a FIT image adds quite a bit of
1535 code to SPL. So this is normally disabled in SPL. Use this
1536 option to re-enable it. This will affect the output of the
1537 bootm command when booting a FIT image.
1538
wdenkc0aa5c52003-12-06 19:49:23 +00001539- Interrupt support (PPC):
1540
wdenk1ebf41e2004-01-02 14:00:00 +00001541 There are common interrupt_init() and timer_interrupt()
1542 for all PPC archs. interrupt_init() calls interrupt_init_cpu()
Marcel Ziswilerabd8dcb2008-07-09 08:17:15 +02001543 for CPU specific initialization. interrupt_init_cpu()
wdenk1ebf41e2004-01-02 14:00:00 +00001544 should set decrementer_count to appropriate value. If
Marcel Ziswilerabd8dcb2008-07-09 08:17:15 +02001545 CPU resets decrementer automatically after interrupt
wdenk1ebf41e2004-01-02 14:00:00 +00001546 (ppc4xx) it should set decrementer_count to zero.
Marcel Ziswilerabd8dcb2008-07-09 08:17:15 +02001547 timer_interrupt() calls timer_interrupt_cpu() for CPU
wdenk1ebf41e2004-01-02 14:00:00 +00001548 specific handling. If board has watchdog / status_led
1549 / other_activity_monitor it works automatically from
1550 general timer_interrupt().
wdenkc0aa5c52003-12-06 19:49:23 +00001551
wdenkc6097192002-11-03 00:24:07 +00001552
Helmut Raigerd5a184b2011-10-20 04:19:47 +00001553Board initialization settings:
1554------------------------------
1555
1556During Initialization u-boot calls a number of board specific functions
1557to allow the preparation of board specific prerequisites, e.g. pin setup
1558before drivers are initialized. To enable these callbacks the
1559following configuration macros have to be defined. Currently this is
1560architecture specific, so please check arch/your_architecture/lib/board.c
1561typically in board_init_f() and board_init_r().
1562
1563- CONFIG_BOARD_EARLY_INIT_F: Call board_early_init_f()
1564- CONFIG_BOARD_EARLY_INIT_R: Call board_early_init_r()
1565- CONFIG_BOARD_LATE_INIT: Call board_late_init()
wdenkc6097192002-11-03 00:24:07 +00001566
wdenkc6097192002-11-03 00:24:07 +00001567Configuration Settings:
1568-----------------------
1569
Simon Glass8927bf22019-12-28 10:45:10 -07001570- MEM_SUPPORT_64BIT_DATA: Defined automatically if compiled as 64-bit.
York Sun6c480012014-02-26 17:03:19 -08001571 Optionally it can be defined to support 64-bit memory commands.
1572
Jean-Christophe PLAGNIOL-VILLARD03836942008-10-16 15:01:15 +02001573- CONFIG_SYS_LONGHELP: Defined when you want long help messages included;
wdenkc6097192002-11-03 00:24:07 +00001574 undefine this when you're short of memory.
1575
Peter Tyserdfb72b82009-01-27 18:03:12 -06001576- CONFIG_SYS_HELP_CMD_WIDTH: Defined when you want to override the default
1577 width of the commands listed in the 'help' command output.
1578
Jean-Christophe PLAGNIOL-VILLARD03836942008-10-16 15:01:15 +02001579- CONFIG_SYS_PROMPT: This is what U-Boot prints on the console to
wdenkc6097192002-11-03 00:24:07 +00001580 prompt for user input.
1581
Jean-Christophe PLAGNIOL-VILLARD03836942008-10-16 15:01:15 +02001582- CONFIG_SYS_BAUDRATE_TABLE:
wdenkc6097192002-11-03 00:24:07 +00001583 List of legal baudrate settings for this board.
1584
York Sun5d286cd2015-12-04 11:57:07 -08001585- CONFIG_SYS_MEM_RESERVE_SECURE
York Sun1ef95cc2016-06-24 16:46:18 -07001586 Only implemented for ARMv8 for now.
York Sun5d286cd2015-12-04 11:57:07 -08001587 If defined, the size of CONFIG_SYS_MEM_RESERVE_SECURE memory
1588 is substracted from total RAM and won't be reported to OS.
1589 This memory can be used as secure memory. A variable
York Sun1ef95cc2016-06-24 16:46:18 -07001590 gd->arch.secure_ram is used to track the location. In systems
York Sun5d286cd2015-12-04 11:57:07 -08001591 the RAM base is not zero, or RAM is divided into banks,
1592 this variable needs to be recalcuated to get the address.
1593
Jean-Christophe PLAGNIOL-VILLARD03836942008-10-16 15:01:15 +02001594- CONFIG_SYS_LOADS_BAUD_CHANGE:
wdenkc6097192002-11-03 00:24:07 +00001595 Enable temporary baudrate change while serial download
1596
Jean-Christophe PLAGNIOL-VILLARD03836942008-10-16 15:01:15 +02001597- CONFIG_SYS_SDRAM_BASE:
wdenkc6097192002-11-03 00:24:07 +00001598 Physical start address of SDRAM. _Must_ be 0 here.
1599
Jean-Christophe PLAGNIOL-VILLARD03836942008-10-16 15:01:15 +02001600- CONFIG_SYS_FLASH_BASE:
wdenkc6097192002-11-03 00:24:07 +00001601 Physical start address of Flash memory.
1602
Jean-Christophe PLAGNIOL-VILLARD03836942008-10-16 15:01:15 +02001603- CONFIG_SYS_MONITOR_LEN:
wdenk57b2d802003-06-27 21:31:46 +00001604 Size of memory reserved for monitor code, used to
1605 determine _at_compile_time_ (!) if the environment is
1606 embedded within the U-Boot image, or in a separate
1607 flash sector.
wdenkc6097192002-11-03 00:24:07 +00001608
Jean-Christophe PLAGNIOL-VILLARD03836942008-10-16 15:01:15 +02001609- CONFIG_SYS_MALLOC_LEN:
wdenkc6097192002-11-03 00:24:07 +00001610 Size of DRAM reserved for malloc() use.
1611
Simon Glass863e4042014-07-10 22:23:28 -06001612- CONFIG_SYS_MALLOC_F_LEN
1613 Size of the malloc() pool for use before relocation. If
1614 this is defined, then a very simple malloc() implementation
1615 will become available before relocation. The address is just
1616 below the global data, and the stack is moved down to make
1617 space.
1618
1619 This feature allocates regions with increasing addresses
1620 within the region. calloc() is supported, but realloc()
1621 is not available. free() is supported but does nothing.
Jeremiah Mahler03f930c2015-01-04 18:56:50 -08001622 The memory will be freed (or in fact just forgotten) when
Simon Glass863e4042014-07-10 22:23:28 -06001623 U-Boot relocates itself.
1624
Simon Glass9fa901b2014-11-10 17:16:54 -07001625- CONFIG_SYS_MALLOC_SIMPLE
1626 Provides a simple and small malloc() and calloc() for those
1627 boards which do not use the full malloc in SPL (which is
Tom Rini166e3222022-05-27 12:48:32 -04001628 enabled with CONFIG_SYS_SPL_MALLOC).
Simon Glass9fa901b2014-11-10 17:16:54 -07001629
Thierry Redingc97d9742014-12-09 22:25:22 -07001630- CONFIG_SYS_NONCACHED_MEMORY:
1631 Size of non-cached memory area. This area of memory will be
1632 typically located right below the malloc() area and mapped
1633 uncached in the MMU. This is useful for drivers that would
1634 otherwise require a lot of explicit cache maintenance. For
1635 some drivers it's also impossible to properly maintain the
1636 cache. For example if the regions that need to be flushed
1637 are not a multiple of the cache-line size, *and* padding
1638 cannot be allocated between the regions to align them (i.e.
1639 if the HW requires a contiguous array of regions, and the
1640 size of each region is not cache-aligned), then a flush of
1641 one region may result in overwriting data that hardware has
1642 written to another region in the same cache-line. This can
1643 happen for example in network drivers where descriptors for
1644 buffers are typically smaller than the CPU cache-line (e.g.
1645 16 bytes vs. 32 or 64 bytes).
1646
1647 Non-cached memory is only supported on 32-bit ARM at present.
1648
Jean-Christophe PLAGNIOL-VILLARD03836942008-10-16 15:01:15 +02001649- CONFIG_SYS_BOOTMAPSZ:
wdenkc6097192002-11-03 00:24:07 +00001650 Maximum size of memory mapped by the startup code of
1651 the Linux kernel; all data that must be processed by
Bartlomiej Siekac5648c82008-04-14 15:44:16 +02001652 the Linux kernel (bd_info, boot arguments, FDT blob if
1653 used) must be put below this limit, unless "bootm_low"
Robert P. J. Day832d36e2013-09-16 07:15:45 -04001654 environment variable is defined and non-zero. In such case
Bartlomiej Siekac5648c82008-04-14 15:44:16 +02001655 all data for the Linux kernel must be between "bootm_low"
Wolfgang Denk092ae952011-10-26 10:21:21 +00001656 and "bootm_low" + CONFIG_SYS_BOOTMAPSZ. The environment
Grant Likely26396382011-03-28 09:58:43 +00001657 variable "bootm_mapsize" will override the value of
1658 CONFIG_SYS_BOOTMAPSZ. If CONFIG_SYS_BOOTMAPSZ is undefined,
1659 then the value in "bootm_size" will be used instead.
wdenkc6097192002-11-03 00:24:07 +00001660
John Rigbyeea8e692010-10-13 13:57:35 -06001661- CONFIG_SYS_BOOT_GET_CMDLINE:
1662 Enables allocating and saving kernel cmdline in space between
1663 "bootm_low" and "bootm_low" + BOOTMAPSZ.
1664
1665- CONFIG_SYS_BOOT_GET_KBD:
1666 Enables allocating and saving a kernel copy of the bd_info in
1667 space between "bootm_low" and "bootm_low" + BOOTMAPSZ.
1668
Jean-Christophe PLAGNIOL-VILLARD03836942008-10-16 15:01:15 +02001669- CONFIG_SYS_FLASH_PROTECTION
wdenkdccbda02003-07-14 22:13:32 +00001670 If defined, hardware flash sectors protection is used
1671 instead of U-Boot software protection.
1672
Jean-Christophe PLAGNIOL-VILLARD03836942008-10-16 15:01:15 +02001673- CONFIG_SYS_FLASH_CFI:
wdenk4a5c8a72003-03-06 00:02:04 +00001674 Define if the flash driver uses extra elements in the
wdenk2cefd152004-02-08 22:55:38 +00001675 common flash structure for storing flash geometry.
1676
Jean-Christophe PLAGNIOL-VILLARD8d94c232008-08-13 01:40:42 +02001677- CONFIG_FLASH_CFI_DRIVER
wdenk2cefd152004-02-08 22:55:38 +00001678 This option also enables the building of the cfi_flash driver
1679 in the drivers directory
wdenkc6097192002-11-03 00:24:07 +00001680
Piotr Ziecik3e939e92008-11-17 15:57:58 +01001681- CONFIG_FLASH_CFI_MTD
1682 This option enables the building of the cfi_mtd driver
1683 in the drivers directory. The driver exports CFI flash
1684 to the MTD layer.
1685
Jean-Christophe PLAGNIOL-VILLARD03836942008-10-16 15:01:15 +02001686- CONFIG_SYS_FLASH_USE_BUFFER_WRITE
Guennadi Liakhovetski183284f2008-04-03 13:36:02 +02001687 Use buffered writes to flash.
1688
1689- CONFIG_FLASH_SPANSION_S29WS_N
1690 s29ws-n MirrorBit flash has non-standard addresses for buffered
1691 write commands.
1692
Jerry Van Barenaae73572008-03-08 13:48:01 -05001693- CONFIG_FLASH_SHOW_PROGRESS
1694 If defined (must be an integer), print out countdown
1695 digits and dots. Recommended value: 45 (9..1) for 80
1696 column displays, 15 (3..1) for 40 column displays.
1697
Stefan Roesed20cba52013-04-04 15:53:14 +02001698- CONFIG_FLASH_VERIFY
1699 If defined, the content of the flash (destination) is compared
1700 against the source after the write operation. An error message
1701 will be printed when the contents are not identical.
1702 Please note that this option is useless in nearly all cases,
1703 since such flash programming errors usually are detected earlier
1704 while unprotecting/erasing/programming. Please only enable
1705 this option if you really know what you are doing.
1706
Joe Hershberger71497d02012-12-11 22:16:31 -06001707- CONFIG_ENV_FLAGS_LIST_DEFAULT
1708- CONFIG_ENV_FLAGS_LIST_STATIC
Robert P. J. Day832d36e2013-09-16 07:15:45 -04001709 Enable validation of the values given to environment variables when
Joe Hershberger71497d02012-12-11 22:16:31 -06001710 calling env set. Variables can be restricted to only decimal,
1711 hexadecimal, or boolean. If CONFIG_CMD_NET is also defined,
1712 the variables can also be restricted to IP address or MAC address.
1713
1714 The format of the list is:
1715 type_attribute = [s|d|x|b|i|m]
Jeremiah Mahler03f930c2015-01-04 18:56:50 -08001716 access_attribute = [a|r|o|c]
1717 attributes = type_attribute[access_attribute]
Joe Hershberger71497d02012-12-11 22:16:31 -06001718 entry = variable_name[:attributes]
1719 list = entry[,list]
1720
1721 The type attributes are:
1722 s - String (default)
1723 d - Decimal
1724 x - Hexadecimal
1725 b - Boolean ([1yYtT|0nNfF])
1726 i - IP address
1727 m - MAC address
1728
Joe Hershberger6fe26c92012-12-11 22:16:34 -06001729 The access attributes are:
1730 a - Any (default)
1731 r - Read-only
1732 o - Write-once
1733 c - Change-default
1734
Joe Hershberger71497d02012-12-11 22:16:31 -06001735 - CONFIG_ENV_FLAGS_LIST_DEFAULT
1736 Define this to a list (string) to define the ".flags"
Jeremiah Mahler03f930c2015-01-04 18:56:50 -08001737 environment variable in the default or embedded environment.
Joe Hershberger71497d02012-12-11 22:16:31 -06001738
1739 - CONFIG_ENV_FLAGS_LIST_STATIC
1740 Define this to a list (string) to define validation that
1741 should be done if an entry is not found in the ".flags"
1742 environment variable. To override a setting in the static
1743 list, simply add an entry for the same variable name to the
1744 ".flags" variable.
1745
Joe Hershberger6db9fd42015-05-20 14:27:20 -05001746 If CONFIG_REGEX is defined, the variable_name above is evaluated as a
1747 regular expression. This allows multiple variables to define the same
1748 flags without explicitly listing them for each variable.
1749
wdenkc6097192002-11-03 00:24:07 +00001750The following definitions that deal with the placement and management
1751of environment data (variable area); in general, we support the
1752following configurations:
1753
Mike Frysinger63b8f122011-07-08 10:44:25 +00001754- CONFIG_BUILD_ENVCRC:
1755
1756 Builds up envcrc with the target environment so that external utils
1757 may easily extract it and embed it in final U-Boot images.
1758
wdenkc6097192002-11-03 00:24:07 +00001759BE CAREFUL! The first access to the environment happens quite early
Jeremiah Mahler03f930c2015-01-04 18:56:50 -08001760in U-Boot initialization (when we try to get the setting of for the
Marcel Ziswilerabd8dcb2008-07-09 08:17:15 +02001761console baudrate). You *MUST* have mapped your NVRAM area then, or
wdenkc6097192002-11-03 00:24:07 +00001762U-Boot will hang.
1763
1764Please note that even with NVRAM we still use a copy of the
1765environment in RAM: we could work on NVRAM directly, but we want to
1766keep settings there always unmodified except somebody uses "saveenv"
1767to save the current settings.
1768
Liu Gang85bcd732012-03-08 00:33:20 +00001769BE CAREFUL! For some special cases, the local device can not use
1770"saveenv" command. For example, the local device will get the
Liu Gang357bf5a2012-08-09 05:10:01 +00001771environment stored in a remote NOR flash by SRIO or PCIE link,
1772but it can not erase, write this NOR flash by SRIO or PCIE interface.
Liu Gang85bcd732012-03-08 00:33:20 +00001773
Guennadi Liakhovetskifad24442009-05-18 16:07:22 +02001774- CONFIG_NAND_ENV_DST
1775
1776 Defines address in RAM to which the nand_spl code should copy the
1777 environment. If redundant environment is used, it will be copied to
1778 CONFIG_NAND_ENV_DST + CONFIG_ENV_SIZE.
1779
Bruce Adleredecc942007-11-02 13:15:42 -07001780Please note that the environment is read-only until the monitor
wdenkc6097192002-11-03 00:24:07 +00001781has been relocated to RAM and a RAM copy of the environment has been
Simon Glass64b723f2017-08-03 12:22:12 -06001782created; also, when using EEPROM you will have to use env_get_f()
wdenkc6097192002-11-03 00:24:07 +00001783until then to read environment variables.
1784
wdenk8dba0502003-03-31 16:34:49 +00001785The environment is protected by a CRC32 checksum. Before the monitor
1786is relocated into RAM, as a result of a bad CRC you will be working
1787with the compiled-in default environment - *silently*!!! [This is
1788necessary, because the first environment variable we need is the
1789"baudrate" setting for the console - if we have a bad CRC, we don't
1790have any device yet where we could complain.]
wdenkc6097192002-11-03 00:24:07 +00001791
1792Note: once the monitor has been relocated, then it will complain if
1793the default environment is used; a new CRC is computed as soon as you
wdenk8dba0502003-03-31 16:34:49 +00001794use the "saveenv" command to store a valid environment.
wdenkc6097192002-11-03 00:24:07 +00001795
Jean-Christophe PLAGNIOL-VILLARD03836942008-10-16 15:01:15 +02001796- CONFIG_SYS_FAULT_MII_ADDR:
wdenk9c53f402003-10-15 23:53:47 +00001797 MII address of the PHY to check for the Ethernet link state.
wdenkc6097192002-11-03 00:24:07 +00001798
Ron Madriddfa028a2009-02-18 14:30:44 -08001799- CONFIG_NS16550_MIN_FUNCTIONS:
1800 Define this if you desire to only have use of the NS16550_init
1801 and NS16550_putc functions for the serial driver located at
1802 drivers/serial/ns16550.c. This option is useful for saving
1803 space for already greatly restricted images, including but not
1804 limited to NAND_SPL configurations.
1805
Simon Glass28a9e332012-11-30 13:01:18 +00001806- CONFIG_DISPLAY_BOARDINFO
1807 Display information about the board that U-Boot is running on
1808 when U-Boot starts up. The board function checkboard() is called
1809 to do this.
1810
Simon Glasse8822012012-11-30 13:01:19 +00001811- CONFIG_DISPLAY_BOARDINFO_LATE
1812 Similar to the previous option, but display this information
1813 later, once stdio is running and output goes to the LCD, if
1814 present.
1815
wdenkc6097192002-11-03 00:24:07 +00001816Low Level (hardware related) configuration options:
wdenkc8434db2003-03-26 06:55:25 +00001817---------------------------------------------------
wdenkc6097192002-11-03 00:24:07 +00001818
Jean-Christophe PLAGNIOL-VILLARD03836942008-10-16 15:01:15 +02001819- CONFIG_SYS_CACHELINE_SIZE:
wdenkc6097192002-11-03 00:24:07 +00001820 Cache Line Size of the CPU.
1821
Timur Tabid8f341c2011-08-04 18:03:41 -05001822- CONFIG_SYS_CCSRBAR_DEFAULT:
1823 Default (power-on reset) physical address of CCSR on Freescale
1824 PowerPC SOCs.
1825
1826- CONFIG_SYS_CCSRBAR:
1827 Virtual address of CCSR. On a 32-bit build, this is typically
1828 the same value as CONFIG_SYS_CCSRBAR_DEFAULT.
1829
Timur Tabid8f341c2011-08-04 18:03:41 -05001830- CONFIG_SYS_CCSRBAR_PHYS:
1831 Physical address of CCSR. CCSR can be relocated to a new
1832 physical address, if desired. In this case, this macro should
Wolfgang Denk092ae952011-10-26 10:21:21 +00001833 be set to that address. Otherwise, it should be set to the
Timur Tabid8f341c2011-08-04 18:03:41 -05001834 same value as CONFIG_SYS_CCSRBAR_DEFAULT. For example, CCSR
1835 is typically relocated on 36-bit builds. It is recommended
1836 that this macro be defined via the _HIGH and _LOW macros:
1837
1838 #define CONFIG_SYS_CCSRBAR_PHYS ((CONFIG_SYS_CCSRBAR_PHYS_HIGH
1839 * 1ull) << 32 | CONFIG_SYS_CCSRBAR_PHYS_LOW)
1840
1841- CONFIG_SYS_CCSRBAR_PHYS_HIGH:
Wolfgang Denkd590fb12011-10-07 09:58:21 +02001842 Bits 33-36 of CONFIG_SYS_CCSRBAR_PHYS. This value is typically
1843 either 0 (32-bit build) or 0xF (36-bit build). This macro is
Timur Tabid8f341c2011-08-04 18:03:41 -05001844 used in assembly code, so it must not contain typecasts or
1845 integer size suffixes (e.g. "ULL").
1846
1847- CONFIG_SYS_CCSRBAR_PHYS_LOW:
1848 Lower 32-bits of CONFIG_SYS_CCSRBAR_PHYS. This macro is
1849 used in assembly code, so it must not contain typecasts or
1850 integer size suffixes (e.g. "ULL").
1851
Jean-Christophe PLAGNIOL-VILLARD03836942008-10-16 15:01:15 +02001852- CONFIG_SYS_IMMR: Physical address of the Internal Memory.
wdenk07d7e6b2004-12-16 21:44:03 +00001853 DO NOT CHANGE unless you know exactly what you're
Christophe Leroy069fa832017-07-06 10:23:22 +02001854 doing! (11-4) [MPC8xx systems only]
wdenkc6097192002-11-03 00:24:07 +00001855
Jean-Christophe PLAGNIOL-VILLARD03836942008-10-16 15:01:15 +02001856- CONFIG_SYS_INIT_RAM_ADDR:
wdenkc6097192002-11-03 00:24:07 +00001857
wdenkeb20ad32003-09-05 23:19:14 +00001858 Start address of memory area that can be used for
wdenkc6097192002-11-03 00:24:07 +00001859 initial data and stack; please note that this must be
1860 writable memory that is working WITHOUT special
1861 initialization, i. e. you CANNOT use normal RAM which
1862 will become available only after programming the
1863 memory controller and running certain initialization
1864 sequences.
1865
1866 U-Boot uses the following memory types:
Christophe Leroy069fa832017-07-06 10:23:22 +02001867 - MPC8xx: IMMR (internal memory of the CPU)
wdenkc6097192002-11-03 00:24:07 +00001868
Jean-Christophe PLAGNIOL-VILLARD03836942008-10-16 15:01:15 +02001869- CONFIG_SYS_SCCR: System Clock and reset Control Register (15-27)
wdenkc6097192002-11-03 00:24:07 +00001870
Jean-Christophe PLAGNIOL-VILLARD03836942008-10-16 15:01:15 +02001871- CONFIG_SYS_OR_TIMING_SDRAM:
wdenkc6097192002-11-03 00:24:07 +00001872 SDRAM timing
1873
Jean-Christophe PLAGNIOL-VILLARD03836942008-10-16 15:01:15 +02001874- CONFIG_SYS_MAMR_PTA:
wdenkc6097192002-11-03 00:24:07 +00001875 periodic timer for refresh
1876
Kumar Gala8975d7a2010-12-30 12:09:53 -06001877- CONFIG_SYS_SRIO:
1878 Chip has SRIO or not
1879
1880- CONFIG_SRIO1:
1881 Board has SRIO 1 port available
1882
1883- CONFIG_SRIO2:
1884 Board has SRIO 2 port available
1885
Liu Gang27afb9c2013-05-07 16:30:46 +08001886- CONFIG_SRIO_PCIE_BOOT_MASTER
1887 Board can support master function for Boot from SRIO and PCIE
1888
Kumar Gala8975d7a2010-12-30 12:09:53 -06001889- CONFIG_SYS_SRIOn_MEM_VIRT:
1890 Virtual Address of SRIO port 'n' memory region
1891
Simon Glass970b61e2019-11-14 12:57:09 -07001892- CONFIG_SYS_SRIOn_MEM_PHYxS:
Kumar Gala8975d7a2010-12-30 12:09:53 -06001893 Physical Address of SRIO port 'n' memory region
1894
1895- CONFIG_SYS_SRIOn_MEM_SIZE:
1896 Size of SRIO port 'n' memory region
1897
Fabio Estevamf17e8782013-04-11 09:35:34 +00001898- CONFIG_SYS_NAND_BUSWIDTH_16BIT
1899 Defined to tell the NAND controller that the NAND chip is using
1900 a 16 bit bus.
1901 Not all NAND drivers use this symbol.
Fabio Estevam417052b2013-04-11 09:35:35 +00001902 Example of drivers that use it:
Miquel Raynal1f1ae152018-08-16 17:30:07 +02001903 - drivers/mtd/nand/raw/ndfc.c
1904 - drivers/mtd/nand/raw/mxc_nand.c
Alex Watermancd6aae32011-05-19 15:08:36 -04001905
1906- CONFIG_SYS_NDFC_EBC0_CFG
1907 Sets the EBC0_CFG register for the NDFC. If not defined
1908 a default value will be used.
1909
Ben Warren45657152006-09-07 16:50:54 -04001910- CONFIG_SPD_EEPROM
Wolfgang Denkb240aef2008-03-26 10:40:12 +01001911 Get DDR timing information from an I2C EEPROM. Common
1912 with pluggable memory modules such as SODIMMs
1913
Ben Warren45657152006-09-07 16:50:54 -04001914 SPD_EEPROM_ADDRESS
1915 I2C address of the SPD EEPROM
1916
Jean-Christophe PLAGNIOL-VILLARD03836942008-10-16 15:01:15 +02001917- CONFIG_SYS_SPD_BUS_NUM
Wolfgang Denkb240aef2008-03-26 10:40:12 +01001918 If SPD EEPROM is on an I2C bus other than the first
1919 one, specify here. Note that the value must resolve
1920 to something your driver can deal with.
Ben Warren45657152006-09-07 16:50:54 -04001921
York Sunbd495cf2011-09-16 13:21:35 -07001922- CONFIG_FSL_DDR_INTERACTIVE
1923 Enable interactive DDR debugging. See doc/README.fsl-ddr.
1924
York Sun8ced0502015-01-06 13:18:55 -08001925- CONFIG_FSL_DDR_SYNC_REFRESH
1926 Enable sync of refresh for multiple controllers.
1927
York Sunb6a35f82015-03-19 09:30:28 -07001928- CONFIG_FSL_DDR_BIST
1929 Enable built-in memory test for Freescale DDR controllers.
1930
wdenk6203e402004-04-18 10:13:26 +00001931- CONFIG_RMII
1932 Enable RMII mode for all FECs.
1933 Note that this is a global option, we can't
1934 have one FEC in standard MII mode and another in RMII mode.
1935
wdenk20c98a62004-04-23 20:32:05 +00001936- CONFIG_CRC32_VERIFY
1937 Add a verify option to the crc32 command.
1938 The syntax is:
1939
1940 => crc32 -v <address> <count> <crc32>
1941
1942 Where address/count indicate a memory area
1943 and crc32 is the correct crc32 which the
1944 area should have.
1945
wdenk64519362004-07-11 17:40:54 +00001946- CONFIG_LOOPW
1947 Add the "loopw" memory command. This only takes effect if
Simon Glass92ffdee2017-08-04 16:34:27 -06001948 the memory commands are activated globally (CONFIG_CMD_MEMORY).
wdenk64519362004-07-11 17:40:54 +00001949
Joel Johnsondb5a97e2020-01-29 09:17:18 -07001950- CONFIG_CMD_MX_CYCLIC
stroesecc3af832004-12-16 18:46:55 +00001951 Add the "mdc" and "mwc" memory commands. These are cyclic
1952 "md/mw" commands.
1953 Examples:
1954
wdenk07d7e6b2004-12-16 21:44:03 +00001955 => mdc.b 10 4 500
stroesecc3af832004-12-16 18:46:55 +00001956 This command will print 4 bytes (10,11,12,13) each 500 ms.
1957
wdenk07d7e6b2004-12-16 21:44:03 +00001958 => mwc.l 100 12345678 10
stroesecc3af832004-12-16 18:46:55 +00001959 This command will write 12345678 to address 100 all 10 ms.
1960
wdenk07d7e6b2004-12-16 21:44:03 +00001961 This only takes effect if the memory commands are activated
Simon Glass92ffdee2017-08-04 16:34:27 -06001962 globally (CONFIG_CMD_MEMORY).
stroesecc3af832004-12-16 18:46:55 +00001963
Aneesh V552a3192011-07-13 05:11:07 +00001964- CONFIG_SPL_BUILD
Thomas Hebbfd37f242019-11-13 18:18:03 -08001965 Set when the currently-running compilation is for an artifact
1966 that will end up in the SPL (as opposed to the TPL or U-Boot
1967 proper). Code that needs stage-specific behavior should check
1968 this.
wdenk336b2bc2005-04-02 23:52:25 +00001969
Ying Zhang2d2e3b62013-08-16 15:16:15 +08001970- CONFIG_TPL_BUILD
Thomas Hebbfd37f242019-11-13 18:18:03 -08001971 Set when the currently-running compilation is for an artifact
1972 that will end up in the TPL (as opposed to the SPL or U-Boot
1973 proper). Code that needs stage-specific behavior should check
1974 this.
Ying Zhang2d2e3b62013-08-16 15:16:15 +08001975
Simon Glass17dabf02013-02-24 17:33:14 +00001976- CONFIG_ARCH_MAP_SYSMEM
1977 Generally U-Boot (and in particular the md command) uses
1978 effective address. It is therefore not necessary to regard
1979 U-Boot address as virtual addresses that need to be translated
1980 to physical addresses. However, sandbox requires this, since
1981 it maintains its own little RAM buffer which contains all
1982 addressable memory. This option causes some memory accesses
1983 to be mapped through map_sysmem() / unmap_sysmem().
1984
Simon Glassbfb59802013-02-14 04:18:54 +00001985- CONFIG_X86_RESET_VECTOR
1986 If defined, the x86 reset vector code is included. This is not
1987 needed when U-Boot is running from Coreboot.
Gabe Black14f82462012-11-27 21:08:06 +00001988
Karicheri, Muralidharanc1dc61b2014-04-04 13:16:50 -04001989- CONFIG_SYS_NAND_NO_SUBPAGE_WRITE
1990 Option to disable subpage write in NAND driver
1991 driver that uses this:
Miquel Raynal1f1ae152018-08-16 17:30:07 +02001992 drivers/mtd/nand/raw/davinci_nand.c
Karicheri, Muralidharanc1dc61b2014-04-04 13:16:50 -04001993
Timur Tabi275f4bb2011-11-22 09:21:25 -06001994Freescale QE/FMAN Firmware Support:
1995-----------------------------------
1996
1997The Freescale QUICCEngine (QE) and Frame Manager (FMAN) both support the
1998loading of "firmware", which is encoded in the QE firmware binary format.
1999This firmware often needs to be loaded during U-Boot booting, so macros
2000are used to identify the storage device (NOR flash, SPI, etc) and the address
2001within that device.
2002
Zhao Qiang83a90842014-03-21 16:21:44 +08002003- CONFIG_SYS_FMAN_FW_ADDR
2004 The address in the storage device where the FMAN microcode is located. The
Tom Rinifa911f82019-05-12 07:59:12 -04002005 meaning of this address depends on which CONFIG_SYS_QE_FMAN_FW_IN_xxx macro
Zhao Qiang83a90842014-03-21 16:21:44 +08002006 is also specified.
2007
2008- CONFIG_SYS_QE_FW_ADDR
2009 The address in the storage device where the QE microcode is located. The
Tom Rinifa911f82019-05-12 07:59:12 -04002010 meaning of this address depends on which CONFIG_SYS_QE_FMAN_FW_IN_xxx macro
Timur Tabi275f4bb2011-11-22 09:21:25 -06002011 is also specified.
2012
2013- CONFIG_SYS_QE_FMAN_FW_LENGTH
2014 The maximum possible size of the firmware. The firmware binary format
2015 has a field that specifies the actual size of the firmware, but it
2016 might not be possible to read any part of the firmware unless some
2017 local storage is allocated to hold the entire firmware first.
2018
2019- CONFIG_SYS_QE_FMAN_FW_IN_NOR
2020 Specifies that QE/FMAN firmware is located in NOR flash, mapped as
2021 normal addressable memory via the LBC. CONFIG_SYS_FMAN_FW_ADDR is the
2022 virtual address in NOR flash.
2023
2024- CONFIG_SYS_QE_FMAN_FW_IN_NAND
2025 Specifies that QE/FMAN firmware is located in NAND flash.
2026 CONFIG_SYS_FMAN_FW_ADDR is the offset within NAND flash.
2027
2028- CONFIG_SYS_QE_FMAN_FW_IN_MMC
2029 Specifies that QE/FMAN firmware is located on the primary SD/MMC
2030 device. CONFIG_SYS_FMAN_FW_ADDR is the byte offset on that device.
2031
Liu Gang1e084582012-03-08 00:33:18 +00002032- CONFIG_SYS_QE_FMAN_FW_IN_REMOTE
2033 Specifies that QE/FMAN firmware is located in the remote (master)
2034 memory space. CONFIG_SYS_FMAN_FW_ADDR is a virtual address which
Liu Gang357bf5a2012-08-09 05:10:01 +00002035 can be mapped from slave TLB->slave LAW->slave SRIO or PCIE outbound
2036 window->master inbound window->master LAW->the ucode address in
2037 master's memory space.
Timur Tabi275f4bb2011-11-22 09:21:25 -06002038
J. German Rivera8ff14b72014-06-23 15:15:55 -07002039Freescale Layerscape Management Complex Firmware Support:
2040---------------------------------------------------------
2041The Freescale Layerscape Management Complex (MC) supports the loading of
2042"firmware".
2043This firmware often needs to be loaded during U-Boot booting, so macros
2044are used to identify the storage device (NOR flash, SPI, etc) and the address
2045within that device.
2046
2047- CONFIG_FSL_MC_ENET
2048 Enable the MC driver for Layerscape SoCs.
2049
Prabhakar Kushwaha853a9012015-06-02 10:55:52 +05302050Freescale Layerscape Debug Server Support:
2051-------------------------------------------
2052The Freescale Layerscape Debug Server Support supports the loading of
2053"Debug Server firmware" and triggering SP boot-rom.
2054This firmware often needs to be loaded during U-Boot booting.
2055
York Sun928b6812015-12-07 11:08:58 -08002056- CONFIG_SYS_MC_RSV_MEM_ALIGN
2057 Define alignment of reserved memory MC requires
Prabhakar Kushwaha853a9012015-06-02 10:55:52 +05302058
Paul Kocialkowski7b917022015-07-26 18:48:15 +02002059Reproducible builds
2060-------------------
2061
2062In order to achieve reproducible builds, timestamps used in the U-Boot build
2063process have to be set to a fixed value.
2064
2065This is done using the SOURCE_DATE_EPOCH environment variable.
2066SOURCE_DATE_EPOCH is to be set on the build host's shell, not as a configuration
2067option for U-Boot or an environment variable in U-Boot.
2068
2069SOURCE_DATE_EPOCH should be set to a number of seconds since the epoch, in UTC.
2070
wdenkc6097192002-11-03 00:24:07 +00002071Building the Software:
2072======================
2073
Wolfgang Denkb240aef2008-03-26 10:40:12 +01002074Building U-Boot has been tested in several native build environments
2075and in many different cross environments. Of course we cannot support
2076all possibly existing versions of cross development tools in all
2077(potentially obsolete) versions. In case of tool chain problems we
Naoki Hayamae0cc1852020-10-08 13:17:16 +09002078recommend to use the ELDK (see https://www.denx.de/wiki/DULG/ELDK)
Wolfgang Denkb240aef2008-03-26 10:40:12 +01002079which is extensively used to build and test U-Boot.
wdenkc6097192002-11-03 00:24:07 +00002080
Wolfgang Denkb240aef2008-03-26 10:40:12 +01002081If you are not using a native environment, it is assumed that you
2082have GNU cross compiling tools available in your path. In this case,
2083you must set the environment variable CROSS_COMPILE in your shell.
2084Note that no changes to the Makefile or any other source files are
2085necessary. For example using the ELDK on a 4xx CPU, please enter:
wdenkc6097192002-11-03 00:24:07 +00002086
Wolfgang Denkb240aef2008-03-26 10:40:12 +01002087 $ CROSS_COMPILE=ppc_4xx-
2088 $ export CROSS_COMPILE
wdenkc6097192002-11-03 00:24:07 +00002089
Wolfgang Denkb240aef2008-03-26 10:40:12 +01002090U-Boot is intended to be simple to build. After installing the
2091sources you must configure U-Boot for one specific board type. This
wdenkc6097192002-11-03 00:24:07 +00002092is done by typing:
2093
Holger Freyther7ba4e572014-08-04 09:26:05 +02002094 make NAME_defconfig
wdenkc6097192002-11-03 00:24:07 +00002095
Holger Freyther7ba4e572014-08-04 09:26:05 +02002096where "NAME_defconfig" is the name of one of the existing configu-
Heinrich Schuchardtd6e07af2020-02-24 18:36:30 +01002097rations; see configs/*_defconfig for supported names.
wdenk2f0812d2003-10-08 22:45:44 +00002098
Heinrich Schuchardtd6e07af2020-02-24 18:36:30 +01002099Note: for some boards special configuration names may exist; check if
wdenk6c59edc2004-05-03 20:45:30 +00002100 additional information is available from the board vendor; for
2101 instance, the TQM823L systems are available without (standard)
2102 or with LCD support. You can select such additional "features"
Marcel Ziswilerabd8dcb2008-07-09 08:17:15 +02002103 when choosing the configuration, i. e.
wdenkc6097192002-11-03 00:24:07 +00002104
Holger Freyther7ba4e572014-08-04 09:26:05 +02002105 make TQM823L_defconfig
wdenk6c59edc2004-05-03 20:45:30 +00002106 - will configure for a plain TQM823L, i. e. no LCD support
wdenkc6097192002-11-03 00:24:07 +00002107
Holger Freyther7ba4e572014-08-04 09:26:05 +02002108 make TQM823L_LCD_defconfig
wdenk6c59edc2004-05-03 20:45:30 +00002109 - will configure for a TQM823L with U-Boot console on LCD
wdenkc6097192002-11-03 00:24:07 +00002110
wdenk6c59edc2004-05-03 20:45:30 +00002111 etc.
wdenkc6097192002-11-03 00:24:07 +00002112
wdenkc6097192002-11-03 00:24:07 +00002113
wdenk6c59edc2004-05-03 20:45:30 +00002114Finally, type "make all", and you should get some working U-Boot
2115images ready for download to / installation on your system:
wdenkc6097192002-11-03 00:24:07 +00002116
wdenk6c59edc2004-05-03 20:45:30 +00002117- "u-boot.bin" is a raw binary image
2118- "u-boot" is an image in ELF binary format
2119- "u-boot.srec" is in Motorola S-Record format
wdenkc6097192002-11-03 00:24:07 +00002120
Marian Balakowiczefe063f2006-09-07 17:25:40 +02002121By default the build is performed locally and the objects are saved
2122in the source directory. One of the two methods can be used to change
2123this behavior and build U-Boot to some external directory:
2124
21251. Add O= to the make command line invocations:
2126
2127 make O=/tmp/build distclean
Holger Freyther7ba4e572014-08-04 09:26:05 +02002128 make O=/tmp/build NAME_defconfig
Marian Balakowiczefe063f2006-09-07 17:25:40 +02002129 make O=/tmp/build all
2130
Timo Ketolac8c67602014-11-06 14:39:05 +020021312. Set environment variable KBUILD_OUTPUT to point to the desired location:
Marian Balakowiczefe063f2006-09-07 17:25:40 +02002132
Timo Ketolac8c67602014-11-06 14:39:05 +02002133 export KBUILD_OUTPUT=/tmp/build
Marian Balakowiczefe063f2006-09-07 17:25:40 +02002134 make distclean
Holger Freyther7ba4e572014-08-04 09:26:05 +02002135 make NAME_defconfig
Marian Balakowiczefe063f2006-09-07 17:25:40 +02002136 make all
2137
Timo Ketolac8c67602014-11-06 14:39:05 +02002138Note that the command line "O=" setting overrides the KBUILD_OUTPUT environment
Marian Balakowiczefe063f2006-09-07 17:25:40 +02002139variable.
2140
Daniel Schwierzeck88484422018-01-26 16:31:04 +01002141User specific CPPFLAGS, AFLAGS and CFLAGS can be passed to the compiler by
2142setting the according environment variables KCPPFLAGS, KAFLAGS and KCFLAGS.
2143For example to treat all compiler warnings as errors:
2144
2145 make KCFLAGS=-Werror
wdenkc6097192002-11-03 00:24:07 +00002146
wdenk6c59edc2004-05-03 20:45:30 +00002147Please be aware that the Makefiles assume you are using GNU make, so
2148for instance on NetBSD you might need to use "gmake" instead of
2149native "make".
wdenkc6097192002-11-03 00:24:07 +00002150
wdenkc6097192002-11-03 00:24:07 +00002151
wdenk6c59edc2004-05-03 20:45:30 +00002152If the system board that you have is not listed, then you will need
2153to port U-Boot to your hardware platform. To do this, follow these
2154steps:
wdenkc6097192002-11-03 00:24:07 +00002155
Phil Sutterc77b4882015-12-25 14:41:18 +010021561. Create a new directory to hold your board specific code. Add any
wdenk6c59edc2004-05-03 20:45:30 +00002157 files you need. In your board directory, you will need at least
Phil Sutterc77b4882015-12-25 14:41:18 +01002158 the "Makefile" and a "<board>.c".
21592. Create a new configuration file "include/configs/<board>.h" for
2160 your board.
wdenk6c59edc2004-05-03 20:45:30 +000021613. If you're porting U-Boot to a new CPU, then also create a new
2162 directory to hold your CPU specific code. Add any files you need.
Holger Freyther7ba4e572014-08-04 09:26:05 +020021634. Run "make <board>_defconfig" with your new name.
wdenk6c59edc2004-05-03 20:45:30 +000021645. Type "make", and you should get a working "u-boot.srec" file
2165 to be installed on your target system.
21666. Debug and solve any problems that might arise.
2167 [Of course, this last step is much harder than it sounds.]
wdenkc6097192002-11-03 00:24:07 +00002168
wdenkc6097192002-11-03 00:24:07 +00002169
wdenk6c59edc2004-05-03 20:45:30 +00002170Testing of U-Boot Modifications, Ports to New Hardware, etc.:
2171==============================================================
wdenkc6097192002-11-03 00:24:07 +00002172
Wolfgang Denkb240aef2008-03-26 10:40:12 +01002173If you have modified U-Boot sources (for instance added a new board
2174or support for new devices, a new CPU, etc.) you are expected to
wdenk6c59edc2004-05-03 20:45:30 +00002175provide feedback to the other developers. The feedback normally takes
Thomas Hebbfd37f242019-11-13 18:18:03 -08002176the form of a "patch", i.e. a context diff against a certain (latest
Wolfgang Denkb240aef2008-03-26 10:40:12 +01002177official or latest in the git repository) version of U-Boot sources.
wdenkc6097192002-11-03 00:24:07 +00002178
Wolfgang Denkb240aef2008-03-26 10:40:12 +01002179But before you submit such a patch, please verify that your modifi-
2180cation did not break existing code. At least make sure that *ALL* of
wdenk6c59edc2004-05-03 20:45:30 +00002181the supported boards compile WITHOUT ANY compiler warnings. To do so,
Simon Glassdc27def2016-07-27 20:33:08 -06002182just run the buildman script (tools/buildman/buildman), which will
2183configure and build U-Boot for ALL supported system. Be warned, this
2184will take a while. Please see the buildman README, or run 'buildman -H'
2185for documentation.
wdenkc6097192002-11-03 00:24:07 +00002186
Marian Balakowiczefe063f2006-09-07 17:25:40 +02002187
wdenk6c59edc2004-05-03 20:45:30 +00002188See also "U-Boot Porting Guide" below.
wdenkc6097192002-11-03 00:24:07 +00002189
wdenkc6097192002-11-03 00:24:07 +00002190
wdenk6c59edc2004-05-03 20:45:30 +00002191Monitor Commands - Overview:
2192============================
wdenkc6097192002-11-03 00:24:07 +00002193
wdenk6c59edc2004-05-03 20:45:30 +00002194go - start application at address 'addr'
2195run - run commands in an environment variable
2196bootm - boot application image from memory
2197bootp - boot image via network using BootP/TFTP protocol
Marek Vasutcf41a9b2012-03-14 21:52:45 +00002198bootz - boot zImage from memory
wdenk6c59edc2004-05-03 20:45:30 +00002199tftpboot- boot image via network using TFTP protocol
2200 and env variables "ipaddr" and "serverip"
2201 (and eventually "gatewayip")
Simon Glass6a398d22011-10-24 18:00:07 +00002202tftpput - upload a file via network using TFTP protocol
wdenk6c59edc2004-05-03 20:45:30 +00002203rarpboot- boot image via network using RARP/TFTP protocol
2204diskboot- boot from IDE devicebootd - boot default, i.e., run 'bootcmd'
2205loads - load S-Record file over serial line
2206loadb - load binary file over serial line (kermit mode)
Rui Miguel Silva433f15a2022-05-11 10:55:40 +01002207loadm - load binary blob from source address to destination address
wdenk6c59edc2004-05-03 20:45:30 +00002208md - memory display
2209mm - memory modify (auto-incrementing)
2210nm - memory modify (constant address)
2211mw - memory write (fill)
Simon Glass19038de2020-06-02 19:26:49 -06002212ms - memory search
wdenk6c59edc2004-05-03 20:45:30 +00002213cp - memory copy
2214cmp - memory compare
2215crc32 - checksum calculation
Peter Tyser469cde42009-04-18 22:34:03 -05002216i2c - I2C sub-system
wdenk6c59edc2004-05-03 20:45:30 +00002217sspi - SPI utility commands
2218base - print or set address offset
2219printenv- print environment variables
Pragnesh Patel1d5955f2020-12-22 11:30:05 +05302220pwm - control pwm channels
wdenk6c59edc2004-05-03 20:45:30 +00002221setenv - set environment variables
2222saveenv - save environment variables to persistent storage
2223protect - enable or disable FLASH write protection
2224erase - erase FLASH memory
2225flinfo - print FLASH memory information
Karl O. Pinc4baf03d2012-08-03 05:57:21 +00002226nand - NAND memory operations (see doc/README.nand)
wdenk6c59edc2004-05-03 20:45:30 +00002227bdinfo - print Board Info structure
2228iminfo - print header information for application image
2229coninfo - print console devices and informations
2230ide - IDE sub-system
2231loop - infinite loop on address range
wdenk64519362004-07-11 17:40:54 +00002232loopw - infinite write loop on address range
wdenk6c59edc2004-05-03 20:45:30 +00002233mtest - simple RAM test
2234icache - enable or disable instruction cache
2235dcache - enable or disable data cache
2236reset - Perform RESET of the CPU
2237echo - echo args to console
2238version - print monitor version
2239help - print online help
2240? - alias for 'help'
wdenkc6097192002-11-03 00:24:07 +00002241
wdenkc6097192002-11-03 00:24:07 +00002242
wdenk6c59edc2004-05-03 20:45:30 +00002243Monitor Commands - Detailed Description:
2244========================================
wdenkc6097192002-11-03 00:24:07 +00002245
wdenk6c59edc2004-05-03 20:45:30 +00002246TODO.
wdenkc6097192002-11-03 00:24:07 +00002247
wdenk6c59edc2004-05-03 20:45:30 +00002248For now: just type "help <command>".
wdenkc6097192002-11-03 00:24:07 +00002249
2250
wdenk6c59edc2004-05-03 20:45:30 +00002251Note for Redundant Ethernet Interfaces:
2252=======================================
wdenkf4688a22003-05-28 08:06:31 +00002253
Marcel Ziswilerabd8dcb2008-07-09 08:17:15 +02002254Some boards come with redundant Ethernet interfaces; U-Boot supports
wdenk6c59edc2004-05-03 20:45:30 +00002255such configurations and is capable of automatic selection of a
2256"working" interface when needed. MAC assignment works as follows:
wdenkf4688a22003-05-28 08:06:31 +00002257
wdenk6c59edc2004-05-03 20:45:30 +00002258Network interfaces are numbered eth0, eth1, eth2, ... Corresponding
2259MAC addresses can be stored in the environment as "ethaddr" (=>eth0),
2260"eth1addr" (=>eth1), "eth2addr", ...
wdenkf4688a22003-05-28 08:06:31 +00002261
wdenk6c59edc2004-05-03 20:45:30 +00002262If the network interface stores some valid MAC address (for instance
2263in SROM), this is used as default address if there is NO correspon-
2264ding setting in the environment; if the corresponding environment
2265variable is set, this overrides the settings in the card; that means:
wdenkf4688a22003-05-28 08:06:31 +00002266
wdenk6c59edc2004-05-03 20:45:30 +00002267o If the SROM has a valid MAC address, and there is no address in the
2268 environment, the SROM's address is used.
wdenkc6097192002-11-03 00:24:07 +00002269
wdenk6c59edc2004-05-03 20:45:30 +00002270o If there is no valid address in the SROM, and a definition in the
2271 environment exists, then the value from the environment variable is
2272 used.
wdenkc6097192002-11-03 00:24:07 +00002273
wdenk6c59edc2004-05-03 20:45:30 +00002274o If both the SROM and the environment contain a MAC address, and
2275 both addresses are the same, this MAC address is used.
wdenkc6097192002-11-03 00:24:07 +00002276
wdenk6c59edc2004-05-03 20:45:30 +00002277o If both the SROM and the environment contain a MAC address, and the
2278 addresses differ, the value from the environment is used and a
2279 warning is printed.
wdenkc6097192002-11-03 00:24:07 +00002280
wdenk6c59edc2004-05-03 20:45:30 +00002281o If neither SROM nor the environment contain a MAC address, an error
Joe Hershberger2dc2b5d2015-05-04 14:55:13 -05002282 is raised. If CONFIG_NET_RANDOM_ETHADDR is defined, then in this case
2283 a random, locally-assigned MAC is used.
wdenkc6097192002-11-03 00:24:07 +00002284
Ben Warren6db991a2010-04-26 11:11:46 -07002285If Ethernet drivers implement the 'write_hwaddr' function, valid MAC addresses
Wolfgang Denk092ae952011-10-26 10:21:21 +00002286will be programmed into hardware as part of the initialization process. This
Ben Warren6db991a2010-04-26 11:11:46 -07002287may be skipped by setting the appropriate 'ethmacskip' environment variable.
2288The naming convention is as follows:
2289"ethmacskip" (=>eth0), "eth1macskip" (=>eth1) etc.
wdenkc6097192002-11-03 00:24:07 +00002290
wdenk6c59edc2004-05-03 20:45:30 +00002291Image Formats:
2292==============
wdenkc6097192002-11-03 00:24:07 +00002293
Marian Balakowicz18710b82008-03-12 12:13:13 +01002294U-Boot is capable of booting (and performing other auxiliary operations on)
2295images in two formats:
2296
2297New uImage format (FIT)
2298-----------------------
2299
2300Flexible and powerful format based on Flattened Image Tree -- FIT (similar
2301to Flattened Device Tree). It allows the use of images with multiple
2302components (several kernels, ramdisks, etc.), with contents protected by
2303SHA1, MD5 or CRC32. More details are found in the doc/uImage.FIT directory.
2304
2305
2306Old uImage format
2307-----------------
2308
2309Old image format is based on binary files which can be basically anything,
2310preceded by a special header; see the definitions in include/image.h for
2311details; basically, the header defines the following image properties:
wdenkc6097192002-11-03 00:24:07 +00002312
wdenk6c59edc2004-05-03 20:45:30 +00002313* Target Operating System (Provisions for OpenBSD, NetBSD, FreeBSD,
2314 4.4BSD, Linux, SVR4, Esix, Solaris, Irix, SCO, Dell, NCR, VxWorks,
Peter Tyser56b8dd12008-09-08 14:56:49 -05002315 LynxOS, pSOS, QNX, RTEMS, INTEGRITY;
Thomas Huthc90d56a2021-11-13 18:13:50 +01002316 Currently supported: Linux, NetBSD, VxWorks, QNX, RTEMS, INTEGRITY).
Andy Shevchenko8cb5cdd2017-07-05 16:25:22 +03002317* Target CPU Architecture (Provisions for Alpha, ARM, Intel x86,
Tom Rini53320122022-04-06 09:21:25 -04002318 IA64, MIPS, Nios II, PowerPC, IBM S390, SuperH, Sparc, Sparc 64 Bit;
2319 Currently supported: ARM, Intel x86, MIPS, Nios II, PowerPC).
wdenk6c59edc2004-05-03 20:45:30 +00002320* Compression Type (uncompressed, gzip, bzip2)
2321* Load Address
2322* Entry Point
2323* Image Name
2324* Image Timestamp
wdenkc6097192002-11-03 00:24:07 +00002325
wdenk6c59edc2004-05-03 20:45:30 +00002326The header is marked by a special Magic Number, and both the header
2327and the data portions of the image are secured against corruption by
2328CRC32 checksums.
wdenkc6097192002-11-03 00:24:07 +00002329
wdenkc6097192002-11-03 00:24:07 +00002330
wdenk6c59edc2004-05-03 20:45:30 +00002331Linux Support:
2332==============
wdenkc6097192002-11-03 00:24:07 +00002333
wdenk6c59edc2004-05-03 20:45:30 +00002334Although U-Boot should support any OS or standalone application
2335easily, the main focus has always been on Linux during the design of
2336U-Boot.
wdenkc6097192002-11-03 00:24:07 +00002337
wdenk6c59edc2004-05-03 20:45:30 +00002338U-Boot includes many features that so far have been part of some
2339special "boot loader" code within the Linux kernel. Also, any
2340"initrd" images to be used are no longer part of one big Linux image;
2341instead, kernel and "initrd" are separate images. This implementation
2342serves several purposes:
wdenkc6097192002-11-03 00:24:07 +00002343
wdenk6c59edc2004-05-03 20:45:30 +00002344- the same features can be used for other OS or standalone
2345 applications (for instance: using compressed images to reduce the
2346 Flash memory footprint)
wdenkc6097192002-11-03 00:24:07 +00002347
wdenk6c59edc2004-05-03 20:45:30 +00002348- it becomes much easier to port new Linux kernel versions because
2349 lots of low-level, hardware dependent stuff are done by U-Boot
wdenkc6097192002-11-03 00:24:07 +00002350
wdenk6c59edc2004-05-03 20:45:30 +00002351- the same Linux kernel image can now be used with different "initrd"
2352 images; of course this also means that different kernel images can
2353 be run with the same "initrd". This makes testing easier (you don't
2354 have to build a new "zImage.initrd" Linux image when you just
2355 change a file in your "initrd"). Also, a field-upgrade of the
2356 software is easier now.
wdenkc6097192002-11-03 00:24:07 +00002357
wdenkc6097192002-11-03 00:24:07 +00002358
wdenk6c59edc2004-05-03 20:45:30 +00002359Linux HOWTO:
2360============
wdenkc6097192002-11-03 00:24:07 +00002361
wdenk6c59edc2004-05-03 20:45:30 +00002362Porting Linux to U-Boot based systems:
2363---------------------------------------
wdenkc6097192002-11-03 00:24:07 +00002364
wdenk6c59edc2004-05-03 20:45:30 +00002365U-Boot cannot save you from doing all the necessary modifications to
2366configure the Linux device drivers for use with your target hardware
2367(no, we don't intend to provide a full virtual machine interface to
2368Linux :-).
wdenkc6097192002-11-03 00:24:07 +00002369
Stefan Roese88fbf932010-04-15 16:07:28 +02002370But now you can ignore ALL boot loader code (in arch/powerpc/mbxboot).
wdenkc6097192002-11-03 00:24:07 +00002371
wdenk6c59edc2004-05-03 20:45:30 +00002372Just make sure your machine specific header file (for instance
2373include/asm-ppc/tqm8xx.h) includes the same definition of the Board
Markus Heidelberg47167572008-09-07 20:18:27 +02002374Information structure as we define in include/asm-<arch>/u-boot.h,
2375and make sure that your definition of IMAP_ADDR uses the same value
Jean-Christophe PLAGNIOL-VILLARD03836942008-10-16 15:01:15 +02002376as your U-Boot configuration in CONFIG_SYS_IMMR.
wdenkc6097192002-11-03 00:24:07 +00002377
Simon Glassd097e592014-06-11 23:29:46 -06002378Note that U-Boot now has a driver model, a unified model for drivers.
2379If you are adding a new driver, plumb it into driver model. If there
2380is no uclass available, you are encouraged to create one. See
2381doc/driver-model.
2382
wdenkc6097192002-11-03 00:24:07 +00002383
wdenk6c59edc2004-05-03 20:45:30 +00002384Configuring the Linux kernel:
2385-----------------------------
wdenkc6097192002-11-03 00:24:07 +00002386
wdenk6c59edc2004-05-03 20:45:30 +00002387No specific requirements for U-Boot. Make sure you have some root
2388device (initial ramdisk, NFS) for your target system.
wdenkc6097192002-11-03 00:24:07 +00002389
wdenkc6097192002-11-03 00:24:07 +00002390
wdenk6c59edc2004-05-03 20:45:30 +00002391Building a Linux Image:
2392-----------------------
wdenkc6097192002-11-03 00:24:07 +00002393
wdenk6c59edc2004-05-03 20:45:30 +00002394With U-Boot, "normal" build targets like "zImage" or "bzImage" are
2395not used. If you use recent kernel source, a new build target
2396"uImage" will exist which automatically builds an image usable by
2397U-Boot. Most older kernels also have support for a "pImage" target,
2398which was introduced for our predecessor project PPCBoot and uses a
2399100% compatible format.
wdenkc6097192002-11-03 00:24:07 +00002400
wdenk6c59edc2004-05-03 20:45:30 +00002401Example:
wdenkc6097192002-11-03 00:24:07 +00002402
Holger Freyther7ba4e572014-08-04 09:26:05 +02002403 make TQM850L_defconfig
wdenk6c59edc2004-05-03 20:45:30 +00002404 make oldconfig
2405 make dep
2406 make uImage
wdenkc6097192002-11-03 00:24:07 +00002407
wdenk6c59edc2004-05-03 20:45:30 +00002408The "uImage" build target uses a special tool (in 'tools/mkimage') to
2409encapsulate a compressed Linux kernel image with header information,
2410CRC32 checksum etc. for use with U-Boot. This is what we are doing:
wdenkc6097192002-11-03 00:24:07 +00002411
wdenk6c59edc2004-05-03 20:45:30 +00002412* build a standard "vmlinux" kernel image (in ELF binary format):
wdenkc6097192002-11-03 00:24:07 +00002413
wdenk6c59edc2004-05-03 20:45:30 +00002414* convert the kernel into a raw binary image:
wdenkc6097192002-11-03 00:24:07 +00002415
wdenk6c59edc2004-05-03 20:45:30 +00002416 ${CROSS_COMPILE}-objcopy -O binary \
2417 -R .note -R .comment \
2418 -S vmlinux linux.bin
wdenk24ee89b2002-11-03 17:56:27 +00002419
wdenk6c59edc2004-05-03 20:45:30 +00002420* compress the binary image:
wdenk24ee89b2002-11-03 17:56:27 +00002421
wdenk6c59edc2004-05-03 20:45:30 +00002422 gzip -9 linux.bin
wdenk24ee89b2002-11-03 17:56:27 +00002423
wdenk6c59edc2004-05-03 20:45:30 +00002424* package compressed binary image for U-Boot:
wdenk24ee89b2002-11-03 17:56:27 +00002425
wdenk6c59edc2004-05-03 20:45:30 +00002426 mkimage -A ppc -O linux -T kernel -C gzip \
2427 -a 0 -e 0 -n "Linux Kernel Image" \
2428 -d linux.bin.gz uImage
wdenkc6097192002-11-03 00:24:07 +00002429
wdenkc6097192002-11-03 00:24:07 +00002430
wdenk6c59edc2004-05-03 20:45:30 +00002431The "mkimage" tool can also be used to create ramdisk images for use
2432with U-Boot, either separated from the Linux kernel image, or
2433combined into one file. "mkimage" encapsulates the images with a 64
2434byte header containing information about target architecture,
2435operating system, image type, compression method, entry points, time
2436stamp, CRC32 checksums, etc.
wdenkc6097192002-11-03 00:24:07 +00002437
wdenk6c59edc2004-05-03 20:45:30 +00002438"mkimage" can be called in two ways: to verify existing images and
2439print the header information, or to build new images.
wdenk24ee89b2002-11-03 17:56:27 +00002440
wdenk6c59edc2004-05-03 20:45:30 +00002441In the first form (with "-l" option) mkimage lists the information
2442contained in the header of an existing U-Boot image; this includes
2443checksum verification:
wdenk24ee89b2002-11-03 17:56:27 +00002444
wdenk6c59edc2004-05-03 20:45:30 +00002445 tools/mkimage -l image
2446 -l ==> list image header information
wdenk24ee89b2002-11-03 17:56:27 +00002447
wdenk6c59edc2004-05-03 20:45:30 +00002448The second form (with "-d" option) is used to build a U-Boot image
2449from a "data file" which is used as image payload:
wdenk24ee89b2002-11-03 17:56:27 +00002450
wdenk6c59edc2004-05-03 20:45:30 +00002451 tools/mkimage -A arch -O os -T type -C comp -a addr -e ep \
2452 -n name -d data_file image
2453 -A ==> set architecture to 'arch'
2454 -O ==> set operating system to 'os'
2455 -T ==> set image type to 'type'
2456 -C ==> set compression type 'comp'
2457 -a ==> set load address to 'addr' (hex)
2458 -e ==> set entry point to 'ep' (hex)
2459 -n ==> set image name to 'name'
2460 -d ==> use image data from 'datafile'
wdenk24ee89b2002-11-03 17:56:27 +00002461
wdenkcd914452004-05-29 16:53:29 +00002462Right now, all Linux kernels for PowerPC systems use the same load
2463address (0x00000000), but the entry point address depends on the
2464kernel version:
wdenkc6097192002-11-03 00:24:07 +00002465
wdenk6c59edc2004-05-03 20:45:30 +00002466- 2.2.x kernels have the entry point at 0x0000000C,
2467- 2.3.x and later kernels have the entry point at 0x00000000.
wdenkc6097192002-11-03 00:24:07 +00002468
wdenk6c59edc2004-05-03 20:45:30 +00002469So a typical call to build a U-Boot image would read:
wdenkc6097192002-11-03 00:24:07 +00002470
wdenk6c59edc2004-05-03 20:45:30 +00002471 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \
2472 > -A ppc -O linux -T kernel -C gzip -a 0 -e 0 \
Stefan Roese88fbf932010-04-15 16:07:28 +02002473 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux.gz \
wdenk6c59edc2004-05-03 20:45:30 +00002474 > examples/uImage.TQM850L
2475 Image Name: 2.4.4 kernel for TQM850L
2476 Created: Wed Jul 19 02:34:59 2000
2477 Image Type: PowerPC Linux Kernel Image (gzip compressed)
2478 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB
2479 Load Address: 0x00000000
2480 Entry Point: 0x00000000
wdenkc6097192002-11-03 00:24:07 +00002481
wdenk6c59edc2004-05-03 20:45:30 +00002482To verify the contents of the image (or check for corruption):
wdenkc6097192002-11-03 00:24:07 +00002483
wdenk6c59edc2004-05-03 20:45:30 +00002484 -> tools/mkimage -l examples/uImage.TQM850L
2485 Image Name: 2.4.4 kernel for TQM850L
2486 Created: Wed Jul 19 02:34:59 2000
2487 Image Type: PowerPC Linux Kernel Image (gzip compressed)
2488 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB
2489 Load Address: 0x00000000
2490 Entry Point: 0x00000000
wdenkc6097192002-11-03 00:24:07 +00002491
wdenk6c59edc2004-05-03 20:45:30 +00002492NOTE: for embedded systems where boot time is critical you can trade
2493speed for memory and install an UNCOMPRESSED image instead: this
2494needs more space in Flash, but boots much faster since it does not
2495need to be uncompressed:
wdenkc6097192002-11-03 00:24:07 +00002496
Stefan Roese88fbf932010-04-15 16:07:28 +02002497 -> gunzip /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux.gz
wdenk6c59edc2004-05-03 20:45:30 +00002498 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \
2499 > -A ppc -O linux -T kernel -C none -a 0 -e 0 \
Stefan Roese88fbf932010-04-15 16:07:28 +02002500 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux \
wdenk6c59edc2004-05-03 20:45:30 +00002501 > examples/uImage.TQM850L-uncompressed
2502 Image Name: 2.4.4 kernel for TQM850L
2503 Created: Wed Jul 19 02:34:59 2000
2504 Image Type: PowerPC Linux Kernel Image (uncompressed)
2505 Data Size: 792160 Bytes = 773.59 kB = 0.76 MB
2506 Load Address: 0x00000000
2507 Entry Point: 0x00000000
wdenkc6097192002-11-03 00:24:07 +00002508
wdenkc6097192002-11-03 00:24:07 +00002509
wdenk6c59edc2004-05-03 20:45:30 +00002510Similar you can build U-Boot images from a 'ramdisk.image.gz' file
2511when your kernel is intended to use an initial ramdisk:
wdenkc6097192002-11-03 00:24:07 +00002512
wdenk6c59edc2004-05-03 20:45:30 +00002513 -> tools/mkimage -n 'Simple Ramdisk Image' \
2514 > -A ppc -O linux -T ramdisk -C gzip \
2515 > -d /LinuxPPC/images/SIMPLE-ramdisk.image.gz examples/simple-initrd
2516 Image Name: Simple Ramdisk Image
2517 Created: Wed Jan 12 14:01:50 2000
2518 Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
2519 Data Size: 566530 Bytes = 553.25 kB = 0.54 MB
2520 Load Address: 0x00000000
2521 Entry Point: 0x00000000
wdenkc6097192002-11-03 00:24:07 +00002522
Tyler Hicks791c7472020-10-26 10:40:24 -05002523The "dumpimage" tool can be used to disassemble or list the contents of images
2524built by mkimage. See dumpimage's help output (-h) for details.
wdenkc6097192002-11-03 00:24:07 +00002525
wdenk6c59edc2004-05-03 20:45:30 +00002526Installing a Linux Image:
2527-------------------------
wdenkc6097192002-11-03 00:24:07 +00002528
wdenk6c59edc2004-05-03 20:45:30 +00002529To downloading a U-Boot image over the serial (console) interface,
2530you must convert the image to S-Record format:
wdenkc6097192002-11-03 00:24:07 +00002531
wdenk6c59edc2004-05-03 20:45:30 +00002532 objcopy -I binary -O srec examples/image examples/image.srec
wdenkc6097192002-11-03 00:24:07 +00002533
wdenk6c59edc2004-05-03 20:45:30 +00002534The 'objcopy' does not understand the information in the U-Boot
2535image header, so the resulting S-Record file will be relative to
2536address 0x00000000. To load it to a given address, you need to
2537specify the target address as 'offset' parameter with the 'loads'
2538command.
wdenkc6097192002-11-03 00:24:07 +00002539
wdenk6c59edc2004-05-03 20:45:30 +00002540Example: install the image to address 0x40100000 (which on the
2541TQM8xxL is in the first Flash bank):
wdenkc6097192002-11-03 00:24:07 +00002542
wdenk6c59edc2004-05-03 20:45:30 +00002543 => erase 40100000 401FFFFF
wdenkc6097192002-11-03 00:24:07 +00002544
wdenk6c59edc2004-05-03 20:45:30 +00002545 .......... done
2546 Erased 8 sectors
wdenkc6097192002-11-03 00:24:07 +00002547
wdenk6c59edc2004-05-03 20:45:30 +00002548 => loads 40100000
2549 ## Ready for S-Record download ...
2550 ~>examples/image.srec
2551 1 2 3 4 5 6 7 8 9 10 11 12 13 ...
2552 ...
2553 15989 15990 15991 15992
2554 [file transfer complete]
2555 [connected]
2556 ## Start Addr = 0x00000000
wdenkc6097192002-11-03 00:24:07 +00002557
wdenkc6097192002-11-03 00:24:07 +00002558
wdenk6c59edc2004-05-03 20:45:30 +00002559You can check the success of the download using the 'iminfo' command;
Wolfgang Denkb240aef2008-03-26 10:40:12 +01002560this includes a checksum verification so you can be sure no data
wdenk6c59edc2004-05-03 20:45:30 +00002561corruption happened:
wdenkc6097192002-11-03 00:24:07 +00002562
wdenk6c59edc2004-05-03 20:45:30 +00002563 => imi 40100000
wdenkc6097192002-11-03 00:24:07 +00002564
wdenk6c59edc2004-05-03 20:45:30 +00002565 ## Checking Image at 40100000 ...
2566 Image Name: 2.2.13 for initrd on TQM850L
2567 Image Type: PowerPC Linux Kernel Image (gzip compressed)
2568 Data Size: 335725 Bytes = 327 kB = 0 MB
2569 Load Address: 00000000
2570 Entry Point: 0000000c
2571 Verifying Checksum ... OK
wdenkc6097192002-11-03 00:24:07 +00002572
2573
wdenk6c59edc2004-05-03 20:45:30 +00002574Boot Linux:
2575-----------
wdenkc6097192002-11-03 00:24:07 +00002576
wdenk6c59edc2004-05-03 20:45:30 +00002577The "bootm" command is used to boot an application that is stored in
2578memory (RAM or Flash). In case of a Linux kernel image, the contents
2579of the "bootargs" environment variable is passed to the kernel as
2580parameters. You can check and modify this variable using the
2581"printenv" and "setenv" commands:
wdenkc6097192002-11-03 00:24:07 +00002582
wdenkc6097192002-11-03 00:24:07 +00002583
wdenk6c59edc2004-05-03 20:45:30 +00002584 => printenv bootargs
2585 bootargs=root=/dev/ram
wdenkc6097192002-11-03 00:24:07 +00002586
wdenk6c59edc2004-05-03 20:45:30 +00002587 => 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 +00002588
wdenk6c59edc2004-05-03 20:45:30 +00002589 => printenv bootargs
2590 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 +00002591
wdenk6c59edc2004-05-03 20:45:30 +00002592 => bootm 40020000
2593 ## Booting Linux kernel at 40020000 ...
2594 Image Name: 2.2.13 for NFS on TQM850L
2595 Image Type: PowerPC Linux Kernel Image (gzip compressed)
2596 Data Size: 381681 Bytes = 372 kB = 0 MB
2597 Load Address: 00000000
2598 Entry Point: 0000000c
2599 Verifying Checksum ... OK
2600 Uncompressing Kernel Image ... OK
2601 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
2602 Boot arguments: root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
2603 time_init: decrementer frequency = 187500000/60
2604 Calibrating delay loop... 49.77 BogoMIPS
2605 Memory: 15208k available (700k kernel code, 444k data, 32k init) [c0000000,c1000000]
2606 ...
wdenkc6097192002-11-03 00:24:07 +00002607
Marcel Ziswilerabd8dcb2008-07-09 08:17:15 +02002608If you want to boot a Linux kernel with initial RAM disk, you pass
wdenk6c59edc2004-05-03 20:45:30 +00002609the memory addresses of both the kernel and the initrd image (PPBCOOT
2610format!) to the "bootm" command:
wdenkc6097192002-11-03 00:24:07 +00002611
wdenk6c59edc2004-05-03 20:45:30 +00002612 => imi 40100000 40200000
wdenkc6097192002-11-03 00:24:07 +00002613
wdenk6c59edc2004-05-03 20:45:30 +00002614 ## Checking Image at 40100000 ...
2615 Image Name: 2.2.13 for initrd on TQM850L
2616 Image Type: PowerPC Linux Kernel Image (gzip compressed)
2617 Data Size: 335725 Bytes = 327 kB = 0 MB
2618 Load Address: 00000000
2619 Entry Point: 0000000c
2620 Verifying Checksum ... OK
wdenkc6097192002-11-03 00:24:07 +00002621
wdenk6c59edc2004-05-03 20:45:30 +00002622 ## Checking Image at 40200000 ...
2623 Image Name: Simple Ramdisk Image
2624 Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
2625 Data Size: 566530 Bytes = 553 kB = 0 MB
2626 Load Address: 00000000
2627 Entry Point: 00000000
2628 Verifying Checksum ... OK
wdenkc6097192002-11-03 00:24:07 +00002629
wdenk6c59edc2004-05-03 20:45:30 +00002630 => bootm 40100000 40200000
2631 ## Booting Linux kernel at 40100000 ...
2632 Image Name: 2.2.13 for initrd on TQM850L
2633 Image Type: PowerPC Linux Kernel Image (gzip compressed)
2634 Data Size: 335725 Bytes = 327 kB = 0 MB
2635 Load Address: 00000000
2636 Entry Point: 0000000c
2637 Verifying Checksum ... OK
2638 Uncompressing Kernel Image ... OK
2639 ## Loading RAMDisk Image at 40200000 ...
2640 Image Name: Simple Ramdisk Image
2641 Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
2642 Data Size: 566530 Bytes = 553 kB = 0 MB
2643 Load Address: 00000000
2644 Entry Point: 00000000
2645 Verifying Checksum ... OK
2646 Loading Ramdisk ... OK
2647 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
2648 Boot arguments: root=/dev/ram
2649 time_init: decrementer frequency = 187500000/60
2650 Calibrating delay loop... 49.77 BogoMIPS
2651 ...
2652 RAMDISK: Compressed image found at block 0
2653 VFS: Mounted root (ext2 filesystem).
wdenkc6097192002-11-03 00:24:07 +00002654
wdenk6c59edc2004-05-03 20:45:30 +00002655 bash#
wdenkc6097192002-11-03 00:24:07 +00002656
Matthew McClintockefae4ca2006-06-28 10:41:37 -05002657Boot Linux and pass a flat device tree:
2658-----------
2659
2660First, U-Boot must be compiled with the appropriate defines. See the section
2661titled "Linux Kernel Interface" above for a more in depth explanation. The
2662following is an example of how to start a kernel and pass an updated
2663flat device tree:
2664
2665=> print oftaddr
2666oftaddr=0x300000
2667=> print oft
2668oft=oftrees/mpc8540ads.dtb
2669=> tftp $oftaddr $oft
2670Speed: 1000, full duplex
2671Using TSEC0 device
2672TFTP from server 192.168.1.1; our IP address is 192.168.1.101
2673Filename 'oftrees/mpc8540ads.dtb'.
2674Load address: 0x300000
2675Loading: #
2676done
2677Bytes transferred = 4106 (100a hex)
2678=> tftp $loadaddr $bootfile
2679Speed: 1000, full duplex
2680Using TSEC0 device
2681TFTP from server 192.168.1.1; our IP address is 192.168.1.2
2682Filename 'uImage'.
2683Load address: 0x200000
2684Loading:############
2685done
2686Bytes transferred = 1029407 (fb51f hex)
2687=> print loadaddr
2688loadaddr=200000
2689=> print oftaddr
2690oftaddr=0x300000
2691=> bootm $loadaddr - $oftaddr
2692## Booting image at 00200000 ...
Wolfgang Denk018147d2006-11-27 15:32:42 +01002693 Image Name: Linux-2.6.17-dirty
2694 Image Type: PowerPC Linux Kernel Image (gzip compressed)
2695 Data Size: 1029343 Bytes = 1005.2 kB
Matthew McClintockefae4ca2006-06-28 10:41:37 -05002696 Load Address: 00000000
Wolfgang Denk018147d2006-11-27 15:32:42 +01002697 Entry Point: 00000000
Matthew McClintockefae4ca2006-06-28 10:41:37 -05002698 Verifying Checksum ... OK
2699 Uncompressing Kernel Image ... OK
2700Booting using flat device tree at 0x300000
2701Using MPC85xx ADS machine description
2702Memory CAM mapping: CAM0=256Mb, CAM1=256Mb, CAM2=0Mb residual: 0Mb
2703[snip]
2704
2705
wdenk6c59edc2004-05-03 20:45:30 +00002706More About U-Boot Image Types:
2707------------------------------
wdenkc6097192002-11-03 00:24:07 +00002708
wdenk6c59edc2004-05-03 20:45:30 +00002709U-Boot supports the following image types:
wdenkc6097192002-11-03 00:24:07 +00002710
wdenk6c59edc2004-05-03 20:45:30 +00002711 "Standalone Programs" are directly runnable in the environment
2712 provided by U-Boot; it is expected that (if they behave
2713 well) you can continue to work in U-Boot after return from
2714 the Standalone Program.
2715 "OS Kernel Images" are usually images of some Embedded OS which
2716 will take over control completely. Usually these programs
2717 will install their own set of exception handlers, device
2718 drivers, set up the MMU, etc. - this means, that you cannot
2719 expect to re-enter U-Boot except by resetting the CPU.
2720 "RAMDisk Images" are more or less just data blocks, and their
2721 parameters (address, size) are passed to an OS kernel that is
2722 being started.
2723 "Multi-File Images" contain several images, typically an OS
2724 (Linux) kernel image and one or more data images like
2725 RAMDisks. This construct is useful for instance when you want
2726 to boot over the network using BOOTP etc., where the boot
2727 server provides just a single image file, but you want to get
2728 for instance an OS kernel and a RAMDisk image.
wdenkc6097192002-11-03 00:24:07 +00002729
wdenk6c59edc2004-05-03 20:45:30 +00002730 "Multi-File Images" start with a list of image sizes, each
2731 image size (in bytes) specified by an "uint32_t" in network
2732 byte order. This list is terminated by an "(uint32_t)0".
2733 Immediately after the terminating 0 follow the images, one by
2734 one, all aligned on "uint32_t" boundaries (size rounded up to
2735 a multiple of 4 bytes).
wdenkc6097192002-11-03 00:24:07 +00002736
wdenk6c59edc2004-05-03 20:45:30 +00002737 "Firmware Images" are binary images containing firmware (like
2738 U-Boot or FPGA images) which usually will be programmed to
2739 flash memory.
wdenk4fc95692003-02-28 00:49:47 +00002740
wdenk6c59edc2004-05-03 20:45:30 +00002741 "Script files" are command sequences that will be executed by
2742 U-Boot's command interpreter; this feature is especially
2743 useful when you configure U-Boot to use a real shell (hush)
2744 as command interpreter.
wdenk4fc95692003-02-28 00:49:47 +00002745
Marek Vasutcf41a9b2012-03-14 21:52:45 +00002746Booting the Linux zImage:
2747-------------------------
2748
2749On some platforms, it's possible to boot Linux zImage. This is done
2750using the "bootz" command. The syntax of "bootz" command is the same
2751as the syntax of "bootm" command.
2752
Tom Rini45f46d12013-05-16 11:40:11 -04002753Note, defining the CONFIG_SUPPORT_RAW_INITRD allows user to supply
Marek Vasut28850d02012-03-18 11:47:58 +00002754kernel with raw initrd images. The syntax is slightly different, the
2755address of the initrd must be augmented by it's size, in the following
2756format: "<initrd addres>:<initrd size>".
2757
stroeseb9c17c52003-04-04 15:53:41 +00002758
wdenk6c59edc2004-05-03 20:45:30 +00002759Standalone HOWTO:
2760=================
stroeseb9c17c52003-04-04 15:53:41 +00002761
wdenk6c59edc2004-05-03 20:45:30 +00002762One of the features of U-Boot is that you can dynamically load and
2763run "standalone" applications, which can use some resources of
2764U-Boot like console I/O functions or interrupt services.
stroeseb9c17c52003-04-04 15:53:41 +00002765
wdenk6c59edc2004-05-03 20:45:30 +00002766Two simple examples are included with the sources:
wdenk4fc95692003-02-28 00:49:47 +00002767
wdenk6c59edc2004-05-03 20:45:30 +00002768"Hello World" Demo:
2769-------------------
wdenkc6097192002-11-03 00:24:07 +00002770
wdenk6c59edc2004-05-03 20:45:30 +00002771'examples/hello_world.c' contains a small "Hello World" Demo
2772application; it is automatically compiled when you build U-Boot.
2773It's configured to run at address 0x00040004, so you can play with it
2774like that:
wdenkc6097192002-11-03 00:24:07 +00002775
wdenk6c59edc2004-05-03 20:45:30 +00002776 => loads
2777 ## Ready for S-Record download ...
2778 ~>examples/hello_world.srec
2779 1 2 3 4 5 6 7 8 9 10 11 ...
2780 [file transfer complete]
2781 [connected]
2782 ## Start Addr = 0x00040004
wdenkc6097192002-11-03 00:24:07 +00002783
wdenk6c59edc2004-05-03 20:45:30 +00002784 => go 40004 Hello World! This is a test.
2785 ## Starting application at 0x00040004 ...
2786 Hello World
2787 argc = 7
2788 argv[0] = "40004"
2789 argv[1] = "Hello"
2790 argv[2] = "World!"
2791 argv[3] = "This"
2792 argv[4] = "is"
2793 argv[5] = "a"
2794 argv[6] = "test."
2795 argv[7] = "<NULL>"
2796 Hit any key to exit ...
wdenkc6097192002-11-03 00:24:07 +00002797
wdenk6c59edc2004-05-03 20:45:30 +00002798 ## Application terminated, rc = 0x0
wdenkc6097192002-11-03 00:24:07 +00002799
wdenk6c59edc2004-05-03 20:45:30 +00002800Another example, which demonstrates how to register a CPM interrupt
2801handler with the U-Boot code, can be found in 'examples/timer.c'.
2802Here, a CPM timer is set up to generate an interrupt every second.
2803The interrupt service routine is trivial, just printing a '.'
2804character, but this is just a demo program. The application can be
2805controlled by the following keys:
wdenkc6097192002-11-03 00:24:07 +00002806
wdenk6c59edc2004-05-03 20:45:30 +00002807 ? - print current values og the CPM Timer registers
2808 b - enable interrupts and start timer
2809 e - stop timer and disable interrupts
2810 q - quit application
wdenkc6097192002-11-03 00:24:07 +00002811
wdenk6c59edc2004-05-03 20:45:30 +00002812 => loads
2813 ## Ready for S-Record download ...
2814 ~>examples/timer.srec
2815 1 2 3 4 5 6 7 8 9 10 11 ...
2816 [file transfer complete]
2817 [connected]
2818 ## Start Addr = 0x00040004
wdenkc6097192002-11-03 00:24:07 +00002819
wdenk6c59edc2004-05-03 20:45:30 +00002820 => go 40004
2821 ## Starting application at 0x00040004 ...
2822 TIMERS=0xfff00980
2823 Using timer 1
2824 tgcr @ 0xfff00980, tmr @ 0xfff00990, trr @ 0xfff00994, tcr @ 0xfff00998, tcn @ 0xfff0099c, ter @ 0xfff009b0
wdenkc6097192002-11-03 00:24:07 +00002825
wdenk6c59edc2004-05-03 20:45:30 +00002826Hit 'b':
2827 [q, b, e, ?] Set interval 1000000 us
2828 Enabling timer
2829Hit '?':
2830 [q, b, e, ?] ........
2831 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0xef6, ter=0x0
2832Hit '?':
2833 [q, b, e, ?] .
2834 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x2ad4, ter=0x0
2835Hit '?':
2836 [q, b, e, ?] .
2837 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x1efc, ter=0x0
2838Hit '?':
2839 [q, b, e, ?] .
2840 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x169d, ter=0x0
2841Hit 'e':
2842 [q, b, e, ?] ...Stopping timer
2843Hit 'q':
2844 [q, b, e, ?] ## Application terminated, rc = 0x0
wdenkc6097192002-11-03 00:24:07 +00002845
wdenkc6097192002-11-03 00:24:07 +00002846
wdenk6c59edc2004-05-03 20:45:30 +00002847Minicom warning:
2848================
wdenkc6097192002-11-03 00:24:07 +00002849
wdenk6c59edc2004-05-03 20:45:30 +00002850Over time, many people have reported problems when trying to use the
2851"minicom" terminal emulation program for serial download. I (wd)
2852consider minicom to be broken, and recommend not to use it. Under
2853Unix, I recommend to use C-Kermit for general purpose use (and
2854especially for kermit binary protocol download ("loadb" command), and
Karl O. Pinca0189bb2012-10-01 05:11:56 +00002855use "cu" for S-Record download ("loads" command). See
Naoki Hayamae0cc1852020-10-08 13:17:16 +09002856https://www.denx.de/wiki/view/DULG/SystemSetup#Section_4.3.
Karl O. Pinca0189bb2012-10-01 05:11:56 +00002857for help with kermit.
2858
wdenkc6097192002-11-03 00:24:07 +00002859
wdenk6c59edc2004-05-03 20:45:30 +00002860Nevertheless, if you absolutely want to use it try adding this
2861configuration to your "File transfer protocols" section:
wdenkc6097192002-11-03 00:24:07 +00002862
wdenk6c59edc2004-05-03 20:45:30 +00002863 Name Program Name U/D FullScr IO-Red. Multi
2864 X kermit /usr/bin/kermit -i -l %l -s Y U Y N N
2865 Y kermit /usr/bin/kermit -i -l %l -r N D Y N N
wdenk8dba0502003-03-31 16:34:49 +00002866
wdenk8dba0502003-03-31 16:34:49 +00002867
wdenk6c59edc2004-05-03 20:45:30 +00002868NetBSD Notes:
2869=============
wdenkc6097192002-11-03 00:24:07 +00002870
wdenk6c59edc2004-05-03 20:45:30 +00002871Starting at version 0.9.2, U-Boot supports NetBSD both as host
2872(build U-Boot) and target system (boots NetBSD/mpc8xx).
wdenk88e72a32003-06-19 23:04:19 +00002873
wdenk6c59edc2004-05-03 20:45:30 +00002874Building requires a cross environment; it is known to work on
2875NetBSD/i386 with the cross-powerpc-netbsd-1.3 package (you will also
2876need gmake since the Makefiles are not compatible with BSD make).
2877Note that the cross-powerpc package does not install include files;
2878attempting to build U-Boot will fail because <machine/ansi.h> is
2879missing. This file has to be installed and patched manually:
wdenk88e72a32003-06-19 23:04:19 +00002880
wdenk6c59edc2004-05-03 20:45:30 +00002881 # cd /usr/pkg/cross/powerpc-netbsd/include
2882 # mkdir powerpc
2883 # ln -s powerpc machine
2884 # cp /usr/src/sys/arch/powerpc/include/ansi.h powerpc/ansi.h
2885 # ${EDIT} powerpc/ansi.h ## must remove __va_list, _BSD_VA_LIST
wdenk88e72a32003-06-19 23:04:19 +00002886
wdenk6c59edc2004-05-03 20:45:30 +00002887Native builds *don't* work due to incompatibilities between native
2888and U-Boot include files.
wdenkc6097192002-11-03 00:24:07 +00002889
wdenk6c59edc2004-05-03 20:45:30 +00002890Booting assumes that (the first part of) the image booted is a
2891stage-2 loader which in turn loads and then invokes the kernel
2892proper. Loader sources will eventually appear in the NetBSD source
2893tree (probably in sys/arc/mpc8xx/stand/u-boot_stage2/); in the
wdenkd0245fc2005-04-13 10:02:42 +00002894meantime, see ftp://ftp.denx.de/pub/u-boot/ppcboot_stage2.tar.gz
wdenkc6097192002-11-03 00:24:07 +00002895
wdenkc6097192002-11-03 00:24:07 +00002896
wdenk6c59edc2004-05-03 20:45:30 +00002897Implementation Internals:
2898=========================
wdenkc6097192002-11-03 00:24:07 +00002899
wdenk6c59edc2004-05-03 20:45:30 +00002900The following is not intended to be a complete description of every
2901implementation detail. However, it should help to understand the
2902inner workings of U-Boot and make it easier to port it to custom
2903hardware.
wdenkc6097192002-11-03 00:24:07 +00002904
wdenkc6097192002-11-03 00:24:07 +00002905
wdenk6c59edc2004-05-03 20:45:30 +00002906Initial Stack, Global Data:
2907---------------------------
wdenkc6097192002-11-03 00:24:07 +00002908
wdenk6c59edc2004-05-03 20:45:30 +00002909The implementation of U-Boot is complicated by the fact that U-Boot
2910starts running out of ROM (flash memory), usually without access to
2911system RAM (because the memory controller is not initialized yet).
2912This means that we don't have writable Data or BSS segments, and BSS
2913is not initialized as zero. To be able to get a C environment working
2914at all, we have to allocate at least a minimal stack. Implementation
2915options for this are defined and restricted by the CPU used: Some CPU
2916models provide on-chip memory (like the IMMR area on MPC8xx and
2917MPC826x processors), on others (parts of) the data cache can be
2918locked as (mis-) used as memory, etc.
wdenkc6097192002-11-03 00:24:07 +00002919
Wolfgang Denkb240aef2008-03-26 10:40:12 +01002920 Chris Hallinan posted a good summary of these issues to the
Wolfgang Denk290ae6b2008-12-30 22:56:11 +01002921 U-Boot mailing list:
wdenkc6097192002-11-03 00:24:07 +00002922
wdenk6c59edc2004-05-03 20:45:30 +00002923 Subject: RE: [U-Boot-Users] RE: More On Memory Bank x (nothingness)?
2924 From: "Chris Hallinan" <clh@net1plus.com>
2925 Date: Mon, 10 Feb 2003 16:43:46 -0500 (22:43 MET)
2926 ...
wdenkc6097192002-11-03 00:24:07 +00002927
wdenk6c59edc2004-05-03 20:45:30 +00002928 Correct me if I'm wrong, folks, but the way I understand it
2929 is this: Using DCACHE as initial RAM for Stack, etc, does not
2930 require any physical RAM backing up the cache. The cleverness
2931 is that the cache is being used as a temporary supply of
2932 necessary storage before the SDRAM controller is setup. It's
Marcel Ziswilerabd8dcb2008-07-09 08:17:15 +02002933 beyond the scope of this list to explain the details, but you
wdenk6c59edc2004-05-03 20:45:30 +00002934 can see how this works by studying the cache architecture and
2935 operation in the architecture and processor-specific manuals.
wdenkc6097192002-11-03 00:24:07 +00002936
wdenk6c59edc2004-05-03 20:45:30 +00002937 OCM is On Chip Memory, which I believe the 405GP has 4K. It
2938 is another option for the system designer to use as an
Marcel Ziswilerabd8dcb2008-07-09 08:17:15 +02002939 initial stack/RAM area prior to SDRAM being available. Either
wdenk6c59edc2004-05-03 20:45:30 +00002940 option should work for you. Using CS 4 should be fine if your
2941 board designers haven't used it for something that would
2942 cause you grief during the initial boot! It is frequently not
2943 used.
wdenkc6097192002-11-03 00:24:07 +00002944
Jean-Christophe PLAGNIOL-VILLARD03836942008-10-16 15:01:15 +02002945 CONFIG_SYS_INIT_RAM_ADDR should be somewhere that won't interfere
wdenk6c59edc2004-05-03 20:45:30 +00002946 with your processor/board/system design. The default value
2947 you will find in any recent u-boot distribution in
Stefan Roese3e1f1b32005-08-01 16:49:12 +02002948 walnut.h should work for you. I'd set it to a value larger
wdenk6c59edc2004-05-03 20:45:30 +00002949 than your SDRAM module. If you have a 64MB SDRAM module, set
2950 it above 400_0000. Just make sure your board has no resources
2951 that are supposed to respond to that address! That code in
2952 start.S has been around a while and should work as is when
2953 you get the config right.
wdenk4a5c8a72003-03-06 00:02:04 +00002954
wdenk6c59edc2004-05-03 20:45:30 +00002955 -Chris Hallinan
2956 DS4.COM, Inc.
wdenk4a5c8a72003-03-06 00:02:04 +00002957
wdenk6c59edc2004-05-03 20:45:30 +00002958It is essential to remember this, since it has some impact on the C
2959code for the initialization procedures:
wdenk4a5c8a72003-03-06 00:02:04 +00002960
wdenk6c59edc2004-05-03 20:45:30 +00002961* Initialized global data (data segment) is read-only. Do not attempt
2962 to write it.
wdenk4a5c8a72003-03-06 00:02:04 +00002963
Jeremiah Mahler03f930c2015-01-04 18:56:50 -08002964* Do not use any uninitialized global data (or implicitly initialized
wdenk6c59edc2004-05-03 20:45:30 +00002965 as zero data - BSS segment) at all - this is undefined, initiali-
2966 zation is performed later (when relocating to RAM).
wdenk4a5c8a72003-03-06 00:02:04 +00002967
wdenk6c59edc2004-05-03 20:45:30 +00002968* Stack space is very limited. Avoid big data buffers or things like
2969 that.
wdenk4a5c8a72003-03-06 00:02:04 +00002970
wdenk6c59edc2004-05-03 20:45:30 +00002971Having only the stack as writable memory limits means we cannot use
Jeremiah Mahler03f930c2015-01-04 18:56:50 -08002972normal global data to share information between the code. But it
wdenk6c59edc2004-05-03 20:45:30 +00002973turned out that the implementation of U-Boot can be greatly
2974simplified by making a global data structure (gd_t) available to all
2975functions. We could pass a pointer to this data as argument to _all_
2976functions, but this would bloat the code. Instead we use a feature of
2977the GCC compiler (Global Register Variables) to share the data: we
2978place a pointer (gd) to the global data into a register which we
2979reserve for this purpose.
wdenkc6097192002-11-03 00:24:07 +00002980
wdenk6c59edc2004-05-03 20:45:30 +00002981When choosing a register for such a purpose we are restricted by the
2982relevant (E)ABI specifications for the current architecture, and by
2983GCC's implementation.
wdenkc6097192002-11-03 00:24:07 +00002984
wdenk6c59edc2004-05-03 20:45:30 +00002985For PowerPC, the following registers have specific use:
2986 R1: stack pointer
Wolfgang Denk69c09642008-02-14 22:43:22 +01002987 R2: reserved for system use
wdenk6c59edc2004-05-03 20:45:30 +00002988 R3-R4: parameter passing and return values
2989 R5-R10: parameter passing
2990 R13: small data area pointer
2991 R30: GOT pointer
2992 R31: frame pointer
wdenkc6097192002-11-03 00:24:07 +00002993
Joakim Tjernlund693c0c12010-01-19 14:41:58 +01002994 (U-Boot also uses R12 as internal GOT pointer. r12
2995 is a volatile register so r12 needs to be reset when
2996 going back and forth between asm and C)
wdenkc6097192002-11-03 00:24:07 +00002997
Wolfgang Denk69c09642008-02-14 22:43:22 +01002998 ==> U-Boot will use R2 to hold a pointer to the global data
wdenkc6097192002-11-03 00:24:07 +00002999
wdenk6c59edc2004-05-03 20:45:30 +00003000 Note: on PPC, we could use a static initializer (since the
3001 address of the global data structure is known at compile time),
3002 but it turned out that reserving a register results in somewhat
3003 smaller code - although the code savings are not that big (on
3004 average for all boards 752 bytes for the whole U-Boot image,
3005 624 text + 127 data).
wdenkc6097192002-11-03 00:24:07 +00003006
wdenk6c59edc2004-05-03 20:45:30 +00003007On ARM, the following registers are used:
wdenkc6097192002-11-03 00:24:07 +00003008
wdenk6c59edc2004-05-03 20:45:30 +00003009 R0: function argument word/integer result
3010 R1-R3: function argument word
Jeroen Hofsteea556aca2013-09-21 14:04:42 +02003011 R9: platform specific
3012 R10: stack limit (used only if stack checking is enabled)
wdenk6c59edc2004-05-03 20:45:30 +00003013 R11: argument (frame) pointer
3014 R12: temporary workspace
3015 R13: stack pointer
3016 R14: link register
3017 R15: program counter
wdenkc6097192002-11-03 00:24:07 +00003018
Jeroen Hofsteea556aca2013-09-21 14:04:42 +02003019 ==> U-Boot will use R9 to hold a pointer to the global data
3020
3021 Note: on ARM, only R_ARM_RELATIVE relocations are supported.
wdenkc6097192002-11-03 00:24:07 +00003022
Thomas Chou8fa38582010-05-21 11:08:03 +08003023On Nios II, the ABI is documented here:
Naoki Hayamae0cc1852020-10-08 13:17:16 +09003024 https://www.altera.com/literature/hb/nios2/n2cpu_nii51016.pdf
Thomas Chou8fa38582010-05-21 11:08:03 +08003025
3026 ==> U-Boot will use gp to hold a pointer to the global data
3027
3028 Note: on Nios II, we give "-G0" option to gcc and don't use gp
3029 to access small data sections, so gp is free.
3030
Rick Chend7e6f922017-12-26 13:55:59 +08003031On RISC-V, the following registers are used:
3032
3033 x0: hard-wired zero (zero)
3034 x1: return address (ra)
3035 x2: stack pointer (sp)
3036 x3: global pointer (gp)
3037 x4: thread pointer (tp)
3038 x5: link register (t0)
3039 x8: frame pointer (fp)
3040 x10-x11: arguments/return values (a0-1)
3041 x12-x17: arguments (a2-7)
3042 x28-31: temporaries (t3-6)
3043 pc: program counter (pc)
3044
3045 ==> U-Boot will use gp to hold a pointer to the global data
3046
wdenk6c59edc2004-05-03 20:45:30 +00003047Memory Management:
3048------------------
wdenkc6097192002-11-03 00:24:07 +00003049
wdenk6c59edc2004-05-03 20:45:30 +00003050U-Boot runs in system state and uses physical addresses, i.e. the
3051MMU is not used either for address mapping nor for memory protection.
wdenkc6097192002-11-03 00:24:07 +00003052
wdenk6c59edc2004-05-03 20:45:30 +00003053The available memory is mapped to fixed addresses using the memory
3054controller. In this process, a contiguous block is formed for each
3055memory type (Flash, SDRAM, SRAM), even when it consists of several
3056physical memory banks.
wdenkc6097192002-11-03 00:24:07 +00003057
wdenk6c59edc2004-05-03 20:45:30 +00003058U-Boot is installed in the first 128 kB of the first Flash bank (on
3059TQM8xxL modules this is the range 0x40000000 ... 0x4001FFFF). After
3060booting and sizing and initializing DRAM, the code relocates itself
3061to the upper end of DRAM. Immediately below the U-Boot code some
Jean-Christophe PLAGNIOL-VILLARD03836942008-10-16 15:01:15 +02003062memory is reserved for use by malloc() [see CONFIG_SYS_MALLOC_LEN
wdenk6c59edc2004-05-03 20:45:30 +00003063configuration setting]. Below that, a structure with global Board
3064Info data is placed, followed by the stack (growing downward).
wdenkc6097192002-11-03 00:24:07 +00003065
wdenk6c59edc2004-05-03 20:45:30 +00003066Additionally, some exception handler code is copied to the low 8 kB
3067of DRAM (0x00000000 ... 0x00001FFF).
wdenkc6097192002-11-03 00:24:07 +00003068
wdenk6c59edc2004-05-03 20:45:30 +00003069So a typical memory configuration with 16 MB of DRAM could look like
3070this:
wdenkc6097192002-11-03 00:24:07 +00003071
wdenk6c59edc2004-05-03 20:45:30 +00003072 0x0000 0000 Exception Vector code
3073 :
3074 0x0000 1FFF
3075 0x0000 2000 Free for Application Use
3076 :
3077 :
wdenkc6097192002-11-03 00:24:07 +00003078
wdenk6c59edc2004-05-03 20:45:30 +00003079 :
3080 :
3081 0x00FB FF20 Monitor Stack (Growing downward)
3082 0x00FB FFAC Board Info Data and permanent copy of global data
3083 0x00FC 0000 Malloc Arena
3084 :
3085 0x00FD FFFF
3086 0x00FE 0000 RAM Copy of Monitor Code
3087 ... eventually: LCD or video framebuffer
3088 ... eventually: pRAM (Protected RAM - unchanged by reset)
3089 0x00FF FFFF [End of RAM]
wdenkc6097192002-11-03 00:24:07 +00003090
wdenkc6097192002-11-03 00:24:07 +00003091
wdenk6c59edc2004-05-03 20:45:30 +00003092System Initialization:
3093----------------------
wdenkc6097192002-11-03 00:24:07 +00003094
wdenk6c59edc2004-05-03 20:45:30 +00003095In the reset configuration, U-Boot starts at the reset entry point
Marcel Ziswilerabd8dcb2008-07-09 08:17:15 +02003096(on most PowerPC systems at address 0x00000100). Because of the reset
Jeremiah Mahler03f930c2015-01-04 18:56:50 -08003097configuration for CS0# this is a mirror of the on board Flash memory.
wdenk6c59edc2004-05-03 20:45:30 +00003098To be able to re-map memory U-Boot then jumps to its link address.
3099To be able to implement the initialization code in C, a (small!)
3100initial stack is set up in the internal Dual Ported RAM (in case CPUs
Heiko Schocher71cb3e92017-06-07 17:33:10 +02003101which provide such a feature like), or in a locked part of the data
3102cache. After that, U-Boot initializes the CPU core, the caches and
3103the SIU.
wdenkc6097192002-11-03 00:24:07 +00003104
wdenk6c59edc2004-05-03 20:45:30 +00003105Next, all (potentially) available memory banks are mapped using a
3106preliminary mapping. For example, we put them on 512 MB boundaries
3107(multiples of 0x20000000: SDRAM on 0x00000000 and 0x20000000, Flash
3108on 0x40000000 and 0x60000000, SRAM on 0x80000000). Then UPM A is
3109programmed for SDRAM access. Using the temporary configuration, a
3110simple memory test is run that determines the size of the SDRAM
3111banks.
wdenkc6097192002-11-03 00:24:07 +00003112
wdenk6c59edc2004-05-03 20:45:30 +00003113When there is more than one SDRAM bank, and the banks are of
3114different size, the largest is mapped first. For equal size, the first
3115bank (CS2#) is mapped first. The first mapping is always for address
31160x00000000, with any additional banks following immediately to create
3117contiguous memory starting from 0.
wdenkc6097192002-11-03 00:24:07 +00003118
wdenk6c59edc2004-05-03 20:45:30 +00003119Then, the monitor installs itself at the upper end of the SDRAM area
3120and allocates memory for use by malloc() and for the global Board
3121Info data; also, the exception vector code is copied to the low RAM
3122pages, and the final stack is set up.
wdenkc6097192002-11-03 00:24:07 +00003123
wdenk6c59edc2004-05-03 20:45:30 +00003124Only after this relocation will you have a "normal" C environment;
3125until that you are restricted in several ways, mostly because you are
3126running from ROM, and because the code will have to be relocated to a
3127new address in RAM.
wdenkc6097192002-11-03 00:24:07 +00003128
wdenkc6097192002-11-03 00:24:07 +00003129
wdenk6c59edc2004-05-03 20:45:30 +00003130U-Boot Porting Guide:
3131----------------------
wdenkc6097192002-11-03 00:24:07 +00003132
wdenk6c59edc2004-05-03 20:45:30 +00003133[Based on messages by Jerry Van Baren in the U-Boot-Users mailing
3134list, October 2002]
wdenkc6097192002-11-03 00:24:07 +00003135
wdenkc6097192002-11-03 00:24:07 +00003136
Jerry Van Barenba0687c2009-07-15 20:42:59 -04003137int main(int argc, char *argv[])
wdenk6c59edc2004-05-03 20:45:30 +00003138{
3139 sighandler_t no_more_time;
wdenkc6097192002-11-03 00:24:07 +00003140
Jerry Van Barenba0687c2009-07-15 20:42:59 -04003141 signal(SIGALRM, no_more_time);
3142 alarm(PROJECT_DEADLINE - toSec (3 * WEEK));
wdenkc6097192002-11-03 00:24:07 +00003143
wdenk6c59edc2004-05-03 20:45:30 +00003144 if (available_money > available_manpower) {
Jerry Van Barenba0687c2009-07-15 20:42:59 -04003145 Pay consultant to port U-Boot;
wdenk6c59edc2004-05-03 20:45:30 +00003146 return 0;
3147 }
wdenkc6097192002-11-03 00:24:07 +00003148
wdenk6c59edc2004-05-03 20:45:30 +00003149 Download latest U-Boot source;
wdenk34b613e2002-12-17 01:51:00 +00003150
Wolfgang Denk290ae6b2008-12-30 22:56:11 +01003151 Subscribe to u-boot mailing list;
wdenkc6097192002-11-03 00:24:07 +00003152
Jerry Van Barenba0687c2009-07-15 20:42:59 -04003153 if (clueless)
3154 email("Hi, I am new to U-Boot, how do I get started?");
wdenkc6097192002-11-03 00:24:07 +00003155
wdenk6c59edc2004-05-03 20:45:30 +00003156 while (learning) {
3157 Read the README file in the top level directory;
Naoki Hayamae0cc1852020-10-08 13:17:16 +09003158 Read https://www.denx.de/wiki/bin/view/DULG/Manual;
Patrick Delaunay9b281fa2020-02-28 15:18:10 +01003159 Read applicable doc/README.*;
wdenk6c59edc2004-05-03 20:45:30 +00003160 Read the source, Luke;
Jerry Van Barenba0687c2009-07-15 20:42:59 -04003161 /* find . -name "*.[chS]" | xargs grep -i <keyword> */
wdenk6c59edc2004-05-03 20:45:30 +00003162 }
wdenkc6097192002-11-03 00:24:07 +00003163
Jerry Van Barenba0687c2009-07-15 20:42:59 -04003164 if (available_money > toLocalCurrency ($2500))
3165 Buy a BDI3000;
3166 else
wdenk6c59edc2004-05-03 20:45:30 +00003167 Add a lot of aggravation and time;
wdenkc6097192002-11-03 00:24:07 +00003168
Jerry Van Barenba0687c2009-07-15 20:42:59 -04003169 if (a similar board exists) { /* hopefully... */
3170 cp -a board/<similar> board/<myboard>
3171 cp include/configs/<similar>.h include/configs/<myboard>.h
3172 } else {
3173 Create your own board support subdirectory;
3174 Create your own board include/configs/<myboard>.h file;
3175 }
3176 Edit new board/<myboard> files
3177 Edit new include/configs/<myboard>.h
wdenkc6097192002-11-03 00:24:07 +00003178
Jerry Van Barenba0687c2009-07-15 20:42:59 -04003179 while (!accepted) {
3180 while (!running) {
3181 do {
3182 Add / modify source code;
3183 } until (compiles);
3184 Debug;
3185 if (clueless)
3186 email("Hi, I am having problems...");
3187 }
3188 Send patch file to the U-Boot email list;
3189 if (reasonable critiques)
3190 Incorporate improvements from email list code review;
3191 else
3192 Defend code as written;
wdenk634d2f72004-04-15 23:14:49 +00003193 }
wdenkc6097192002-11-03 00:24:07 +00003194
wdenk6c59edc2004-05-03 20:45:30 +00003195 return 0;
3196}
wdenkc6097192002-11-03 00:24:07 +00003197
wdenk6c59edc2004-05-03 20:45:30 +00003198void no_more_time (int sig)
3199{
3200 hire_a_guru();
3201}
wdenkc6097192002-11-03 00:24:07 +00003202
wdenkc6097192002-11-03 00:24:07 +00003203
wdenk6c59edc2004-05-03 20:45:30 +00003204Coding Standards:
3205-----------------
wdenkc6097192002-11-03 00:24:07 +00003206
wdenk6c59edc2004-05-03 20:45:30 +00003207All contributions to U-Boot should conform to the Linux kernel
Baruch Siachb1081252017-12-10 17:34:35 +02003208coding style; see the kernel coding style guide at
3209https://www.kernel.org/doc/html/latest/process/coding-style.html, and the
3210script "scripts/Lindent" in your Linux kernel source directory.
Detlev Zundelaa63d482006-09-01 15:39:02 +02003211
3212Source files originating from a different project (for example the
3213MTD subsystem) are generally exempt from these guidelines and are not
Jeremiah Mahler03f930c2015-01-04 18:56:50 -08003214reformatted to ease subsequent migration to newer versions of those
Detlev Zundelaa63d482006-09-01 15:39:02 +02003215sources.
wdenkc6097192002-11-03 00:24:07 +00003216
Detlev Zundelaa63d482006-09-01 15:39:02 +02003217Please note that U-Boot is implemented in C (and to some small parts in
3218Assembler); no C++ is used, so please do not use C++ style comments (//)
3219in your code.
wdenkad276f22004-01-04 16:28:35 +00003220
wdenk6c59edc2004-05-03 20:45:30 +00003221Please also stick to the following formatting rules:
3222- remove any trailing white space
Wolfgang Denk20bd2a62011-07-27 10:59:55 +00003223- use TAB characters for indentation and vertical alignment, not spaces
wdenk6c59edc2004-05-03 20:45:30 +00003224- make sure NOT to use DOS '\r\n' line feeds
Wolfgang Denk20bd2a62011-07-27 10:59:55 +00003225- do not add more than 2 consecutive empty lines to source files
wdenk6c59edc2004-05-03 20:45:30 +00003226- do not add trailing empty lines to source files
wdenkc6097192002-11-03 00:24:07 +00003227
wdenk6c59edc2004-05-03 20:45:30 +00003228Submissions which do not conform to the standards may be returned
3229with a request to reformat the changes.
wdenkc6097192002-11-03 00:24:07 +00003230
wdenkc6097192002-11-03 00:24:07 +00003231
wdenk6c59edc2004-05-03 20:45:30 +00003232Submitting Patches:
3233-------------------
wdenkc6097192002-11-03 00:24:07 +00003234
wdenk6c59edc2004-05-03 20:45:30 +00003235Since the number of patches for U-Boot is growing, we need to
3236establish some rules. Submissions which do not conform to these rules
3237may be rejected, even when they contain important and valuable stuff.
wdenkc6097192002-11-03 00:24:07 +00003238
Naoki Hayamae0cc1852020-10-08 13:17:16 +09003239Please see https://www.denx.de/wiki/U-Boot/Patches for details.
Wolfgang Denkb240aef2008-03-26 10:40:12 +01003240
Wolfgang Denk290ae6b2008-12-30 22:56:11 +01003241Patches shall be sent to the u-boot mailing list <u-boot@lists.denx.de>;
S. Lockwood-Childsda6d34c2017-11-14 22:56:42 -08003242see https://lists.denx.de/listinfo/u-boot
Wolfgang Denk290ae6b2008-12-30 22:56:11 +01003243
wdenk6c59edc2004-05-03 20:45:30 +00003244When you send a patch, please include the following information with
3245it:
wdenkc6097192002-11-03 00:24:07 +00003246
wdenk6c59edc2004-05-03 20:45:30 +00003247* For bug fixes: a description of the bug and how your patch fixes
3248 this bug. Please try to include a way of demonstrating that the
3249 patch actually fixes something.
wdenkc6097192002-11-03 00:24:07 +00003250
wdenk6c59edc2004-05-03 20:45:30 +00003251* For new features: a description of the feature and your
3252 implementation.
wdenkc6097192002-11-03 00:24:07 +00003253
Robert P. J. Day076ed9b2015-12-19 07:16:10 -05003254* For major contributions, add a MAINTAINERS file with your
3255 information and associated file and directory references.
wdenkc6097192002-11-03 00:24:07 +00003256
Albert ARIBAUD48e910f2013-09-11 15:52:51 +02003257* When you add support for a new board, don't forget to add a
3258 maintainer e-mail address to the boards.cfg file, too.
wdenkc6097192002-11-03 00:24:07 +00003259
wdenk6c59edc2004-05-03 20:45:30 +00003260* If your patch adds new configuration options, don't forget to
3261 document these in the README file.
wdenkc6097192002-11-03 00:24:07 +00003262
Wolfgang Denkb240aef2008-03-26 10:40:12 +01003263* The patch itself. If you are using git (which is *strongly*
3264 recommended) you can easily generate the patch using the
Wolfgang Denk20bd2a62011-07-27 10:59:55 +00003265 "git format-patch". If you then use "git send-email" to send it to
Wolfgang Denkb240aef2008-03-26 10:40:12 +01003266 the U-Boot mailing list, you will avoid most of the common problems
3267 with some other mail clients.
wdenkca9bc762003-07-15 07:45:49 +00003268
Wolfgang Denkb240aef2008-03-26 10:40:12 +01003269 If you cannot use git, use "diff -purN OLD NEW". If your version of
3270 diff does not support these options, then get the latest version of
3271 GNU diff.
wdenkc6097192002-11-03 00:24:07 +00003272
Wolfgang Denkb240aef2008-03-26 10:40:12 +01003273 The current directory when running this command shall be the parent
3274 directory of the U-Boot source tree (i. e. please make sure that
3275 your patch includes sufficient directory information for the
3276 affected files).
3277
3278 We prefer patches as plain text. MIME attachments are discouraged,
3279 and compressed attachments must not be used.
wdenk88e72a32003-06-19 23:04:19 +00003280
wdenk6c59edc2004-05-03 20:45:30 +00003281* If one logical set of modifications affects or creates several
3282 files, all these changes shall be submitted in a SINGLE patch file.
wdenk57b2d802003-06-27 21:31:46 +00003283
wdenk6c59edc2004-05-03 20:45:30 +00003284* Changesets that contain different, unrelated modifications shall be
3285 submitted as SEPARATE patches, one patch per changeset.
wdenk88e72a32003-06-19 23:04:19 +00003286
wdenkc6097192002-11-03 00:24:07 +00003287
wdenk6c59edc2004-05-03 20:45:30 +00003288Notes:
wdenkc6097192002-11-03 00:24:07 +00003289
Simon Glassdc27def2016-07-27 20:33:08 -06003290* Before sending the patch, run the buildman script on your patched
wdenk6c59edc2004-05-03 20:45:30 +00003291 source tree and make sure that no errors or warnings are reported
3292 for any of the boards.
3293
3294* Keep your modifications to the necessary minimum: A patch
3295 containing several unrelated changes or arbitrary reformats will be
3296 returned with a request to re-formatting / split it.
wdenkc6097192002-11-03 00:24:07 +00003297
wdenk6c59edc2004-05-03 20:45:30 +00003298* If you modify existing code, make sure that your new code does not
3299 add to the memory footprint of the code ;-) Small is beautiful!
3300 When adding new features, these should compile conditionally only
3301 (using #ifdef), and the resulting code with the new feature
3302 disabled must not need more memory than the old code without your
3303 modification.
wdenkcbc49a52005-05-03 14:12:25 +00003304
Wolfgang Denk290ae6b2008-12-30 22:56:11 +01003305* Remember that there is a size limit of 100 kB per message on the
3306 u-boot mailing list. Bigger patches will be moderated. If they are
3307 reasonable and not too big, they will be acknowledged. But patches
3308 bigger than the size limit should be avoided.