blob: 12672d2bfb00285eb7acb823954ff6d70631a095 [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
Scott Wood80806962012-08-14 10:14:53 +0000297 CONFIG_SYS_FSL_ERRATUM_A004510
298
299 Enables a workaround for erratum A004510. If set,
300 then CONFIG_SYS_FSL_ERRATUM_A004510_SVR_REV and
Tom Rini376b88a2022-10-28 20:27:13 -0400301 CFG_SYS_FSL_CORENET_SNOOPVEC_COREONLY must be set.
Scott Wood80806962012-08-14 10:14:53 +0000302
303 CONFIG_SYS_FSL_ERRATUM_A004510_SVR_REV
304 CONFIG_SYS_FSL_ERRATUM_A004510_SVR_REV2 (optional)
305
306 Defines one or two SoC revisions (low 8 bits of SVR)
307 for which the A004510 workaround should be applied.
308
309 The rest of SVR is either not relevant to the decision
310 of whether the erratum is present (e.g. p2040 versus
311 p2041) or is implied by the build target, which controls
312 whether CONFIG_SYS_FSL_ERRATUM_A004510 is set.
313
314 See Freescale App Note 4493 for more information about
315 this erratum.
316
Tom Rini376b88a2022-10-28 20:27:13 -0400317 CFG_SYS_FSL_CORENET_SNOOPVEC_COREONLY
Scott Wood80806962012-08-14 10:14:53 +0000318
319 This is the value to write into CCSR offset 0x18600
320 according to the A004510 workaround.
321
Priyanka Jaine9dcaa82013-12-17 14:25:52 +0530322 CONFIG_SYS_FSL_SINGLE_SOURCE_CLK
323 Single Source Clock is clocking mode present in some of FSL SoC's.
324 In this mode, a single differential clock is used to supply
325 clocks to the sysclock, ddrclock and usbclock.
326
Daniel Schwierzeckd8a49ca2012-04-02 02:57:56 +0000327- Generic CPU options:
Daniel Schwierzeckd8a49ca2012-04-02 02:57:56 +0000328
York Sunf0626592013-09-30 09:22:09 -0700329 CONFIG_SYS_FSL_DDR
330 Freescale DDR driver in use. This type of DDR controller is
Tom Rinie5404982021-05-14 21:34:26 -0400331 found in mpc83xx, mpc85xx as well as some ARM core SoCs.
York Sunf0626592013-09-30 09:22:09 -0700332
Tom Rini376b88a2022-10-28 20:27:13 -0400333 CFG_SYS_FSL_DDR_ADDR
York Sunf0626592013-09-30 09:22:09 -0700334 Freescale DDR memory-mapped register base.
335
Prabhakar Kushwaha3c48f582017-02-02 15:01:26 +0530336 CONFIG_SYS_FSL_IFC_CLK_DIV
337 Defines divider of platform clock(clock input to IFC controller).
338
Prabhakar Kushwahabedc5622017-02-02 15:02:00 +0530339 CONFIG_SYS_FSL_LBC_CLK_DIV
340 Defines divider of platform clock(clock input to eLBC controller).
341
Tom Rini376b88a2022-10-28 20:27:13 -0400342 CFG_SYS_FSL_DDR_SDRAM_BASE_PHY
York Sun3a0916d2014-02-10 13:59:43 -0800343 Physical address from the view of DDR controllers. It is the
Tom Rini6a5dccc2022-11-16 13:10:41 -0500344 same as CFG_SYS_DDR_SDRAM_BASE for all Power SoCs. But
York Sun3a0916d2014-02-10 13:59:43 -0800345 it could be different for ARM SoCs.
346
Daniel Schwierzeckd52a6232011-07-27 13:22:39 +0200347- MIPS CPU options:
Daniel Schwierzeckd52a6232011-07-27 13:22:39 +0200348 CONFIG_XWAY_SWAP_BYTES
349
350 Enable compilation of tools/xway-swap-bytes needed for Lantiq
351 XWAY SoCs for booting from NOR flash. The U-Boot image needs to
352 be swapped if a flash programmer is used.
353
Christian Riesch48c2d6d2012-02-02 00:44:39 +0000354- ARM options:
Tom Rini6a5dccc2022-11-16 13:10:41 -0500355 CFG_SYS_EXCEPTION_VECTORS_HIGH
Christian Riesch48c2d6d2012-02-02 00:44:39 +0000356
357 Select high exception vectors of the ARM core, e.g., do not
358 clear the V bit of the c1 register of CP15.
359
York Sun77a10972015-03-20 19:28:08 -0700360 COUNTER_FREQUENCY
361 Generic timer clock source frequency.
362
363 COUNTER_FREQUENCY_REAL
364 Generic timer clock source frequency if the real clock is
365 different from COUNTER_FREQUENCY, and can only be determined
366 at run time.
367
Stephen Warren8d1fb312015-01-19 16:25:52 -0700368- Tegra SoC options:
369 CONFIG_TEGRA_SUPPORT_NON_SECURE
370
371 Support executing U-Boot in non-secure (NS) mode. Certain
372 impossible actions will be skipped if the CPU is in NS mode,
373 such as ARM architectural timer initialization.
374
wdenk9b7f3842003-10-09 20:09:04 +0000375- Linux Kernel Interface:
Gerald Van Barenfcd91bb2008-06-03 20:34:45 -0400376 CONFIG_OF_LIBFDT
Wolfgang Denk27a5b0b2005-10-13 01:45:54 +0200377
378 New kernel versions are expecting firmware settings to be
Gerald Van Barend6abef42007-03-31 12:23:51 -0400379 passed using flattened device trees (based on open firmware
380 concepts).
381
382 CONFIG_OF_LIBFDT
383 * New libfdt-based support
384 * Adds the "fdt" command
Kim Phillips9b46eb62007-08-10 14:34:14 -0500385 * The bootm command automatically updates the fdt
Gerald Van Barend6abef42007-03-31 12:23:51 -0400386
Wolfgang Denk27a5b0b2005-10-13 01:45:54 +0200387 OF_TBCLK - The timebase frequency.
388
Marcel Ziswilerabd8dcb2008-07-09 08:17:15 +0200389 boards with QUICC Engines require OF_QE to set UCC MAC
390 addresses
Kim Phillips9b46eb62007-08-10 14:34:14 -0500391
Heiko Schocherffb293a2009-09-23 07:56:08 +0200392 CONFIG_OF_IDE_FIXUP
393
394 U-Boot can detect if an IDE device is present or not.
395 If not, and this new config option is activated, U-Boot
396 removes the ATA node from the DTS before booting Linux,
397 so the Linux IDE driver does not probe the device and
398 crash. This is needed for buggy hardware (uc101) where
399 no pull down resistor is connected to the signal IDE5V_DD7.
400
Niklaus Giger0ab978d2008-11-03 22:13:47 +0100401- vxWorks boot parameters:
402
403 bootvx constructs a valid bootline using the following
Bin Mengfb694b92015-10-07 20:19:17 -0700404 environments variables: bootdev, bootfile, ipaddr, netmask,
405 serverip, gatewayip, hostname, othbootargs.
Niklaus Giger0ab978d2008-11-03 22:13:47 +0100406 It loads the vxWorks image pointed bootfile.
407
Naoki Hayama158c2262020-10-08 13:17:08 +0900408 Note: If a "bootargs" environment is defined, it will override
Niklaus Giger0ab978d2008-11-03 22:13:47 +0100409 the defaults discussed just above.
410
Aneesh V686a0752011-06-16 23:30:51 +0000411- Cache Configuration for ARM:
Tom Rini6a5dccc2022-11-16 13:10:41 -0500412 CFG_SYS_PL310_BASE - Physical base address of PL310
Aneesh V686a0752011-06-16 23:30:51 +0000413 controller register space
414
wdenkda04a8b2004-08-02 23:22:59 +0000415- Serial Ports:
Tom Rini5c896ae2022-12-04 10:13:30 -0500416 CFG_PL011_CLOCK
wdenkda04a8b2004-08-02 23:22:59 +0000417
418 If you have Amba PrimeCell PL011 UARTs, set this variable to
419 the clock speed of the UARTs.
420
Tom Rini9fe2b312022-12-04 10:13:31 -0500421 CFG_PL01x_PORTS
wdenkda04a8b2004-08-02 23:22:59 +0000422
423 If you have Amba PrimeCell PL010 or PL011 UARTs on your board,
424 define this to a list of base addresses for each (supported)
425 port. See e.g. include/configs/versatile.h
426
Karicheri, Muralidharancbc08882014-04-09 15:38:46 -0400427 CONFIG_SERIAL_HW_FLOW_CONTROL
428
429 Define this variable to enable hw flow control in serial driver.
430 Current user of this option is drivers/serial/nsl16550.c driver
wdenkda04a8b2004-08-02 23:22:59 +0000431
Simon Glassaa34ef22016-03-13 19:07:28 -0600432- Removal of commands
433 If no commands are needed to boot, you can disable
434 CONFIG_CMDLINE to remove them. In this case, the command line
435 will not be available, and when U-Boot wants to execute the
436 boot command (on start-up) it will call board_run_command()
437 instead. This can reduce image size significantly for very
438 simple boot procedures.
439
Wolfgang Denk2aceea12013-03-23 23:50:31 +0000440- Regular expression support:
441 CONFIG_REGEX
Wolfgang Denkec7fbf52013-10-04 17:43:24 +0200442 If this variable is defined, U-Boot is linked against
443 the SLRE (Super Light Regular Expression) library,
444 which adds regex support to some commands, as for
445 example "env grep" and "setexpr".
Wolfgang Denk2aceea12013-03-23 23:50:31 +0000446
wdenkc6097192002-11-03 00:24:07 +0000447- Watchdog:
Rasmus Villemoes134cc2b2021-04-14 09:18:22 +0200448 CONFIG_SYS_WATCHDOG_FREQ
449 Some platforms automatically call WATCHDOG_RESET()
450 from the timer interrupt handler every
451 CONFIG_SYS_WATCHDOG_FREQ interrupts. If not set by the
452 board configuration file, a default of CONFIG_SYS_HZ/2
453 (i.e. 500) is used. Setting CONFIG_SYS_WATCHDOG_FREQ
454 to 0 disables calling WATCHDOG_RESET() from the timer
455 interrupt.
456
Peter Tyser9902e422008-12-17 16:36:21 -0600457- GPIO Support:
Tom Rini6a5dccc2022-11-16 13:10:41 -0500458 The CFG_SYS_I2C_PCA953X_WIDTH option specifies a list of
Chris Packham9b383202010-12-19 10:12:13 +0000459 chip-ngpio pairs that tell the PCA953X driver the number of
460 pins supported by a particular chip.
461
Peter Tyser9902e422008-12-17 16:36:21 -0600462 Note that if the GPIO device uses I2C, then the I2C interface
463 must also be configured. See I2C Support, below.
464
Simon Glass4dc47ca2014-06-11 23:29:41 -0600465- I/O tracing:
466 When CONFIG_IO_TRACE is selected, U-Boot intercepts all I/O
467 accesses and can checksum them or write a list of them out
468 to memory. See the 'iotrace' command for details. This is
469 useful for testing device drivers since it can confirm that
470 the driver behaves the same way before and after a code
471 change. Currently this is supported on sandbox and arm. To
472 add support for your architecture, add '#include <iotrace.h>'
473 to the bottom of arch/<arch>/include/asm/io.h and test.
474
475 Example output from the 'iotrace stats' command is below.
476 Note that if the trace buffer is exhausted, the checksum will
477 still continue to operate.
478
479 iotrace is enabled
480 Start: 10000000 (buffer start address)
481 Size: 00010000 (buffer size)
482 Offset: 00000120 (current buffer offset)
483 Output: 10000120 (start + offset)
484 Count: 00000018 (number of trace records)
485 CRC32: 9526fb66 (CRC32 of all trace records)
486
wdenkc6097192002-11-03 00:24:07 +0000487- Timestamp Support:
488
wdenk4a5c8a72003-03-06 00:02:04 +0000489 When CONFIG_TIMESTAMP is selected, the timestamp
490 (date and time) of an image is printed by image
491 commands like bootm or iminfo. This option is
Jon Loeligerc1da5c92007-06-11 19:03:39 -0500492 automatically enabled when you select CONFIG_CMD_DATE .
wdenkc6097192002-11-03 00:24:07 +0000493
Karl O. Pinc8b1f90a2012-08-16 06:20:15 +0000494- Partition Labels (disklabels) Supported:
495 Zero or more of the following:
496 CONFIG_MAC_PARTITION Apple's MacOS partition table.
Karl O. Pinc8b1f90a2012-08-16 06:20:15 +0000497 CONFIG_ISO_PARTITION ISO partition table, used on CDROM etc.
498 CONFIG_EFI_PARTITION GPT partition table, common when EFI is the
499 bootloader. Note 2TB partition limit; see
500 disk/part_efi.c
Simon Glass8706b812016-05-01 11:36:02 -0600501 CONFIG_SCSI) you must configure support for at
Karl O. Pinc8b1f90a2012-08-16 06:20:15 +0000502 least one non-MTD partition type as well.
wdenkc6097192002-11-03 00:24:07 +0000503
wdenkc6097192002-11-03 00:24:07 +0000504- NETWORK Support (PCI):
Kyle Moffett64b94dd2011-10-18 11:05:29 +0000505 CONFIG_E1000_SPI
506 Utility code for direct access to the SPI bus on Intel 8257x.
507 This does not do anything useful unless you set at least one
508 of CONFIG_CMD_E1000 or CONFIG_E1000_SPI_GENERIC.
509
wdenkc6097192002-11-03 00:24:07 +0000510 CONFIG_NATSEMI
511 Support for National dp83815 chips.
512
513 CONFIG_NS8382X
514 Support for National dp8382[01] gigabit chips.
515
wdenkaa603362003-05-12 21:50:16 +0000516- NETWORK Support (other):
Rob Herringc9830dc2011-12-15 11:15:49 +0000517 CONFIG_CALXEDA_XGMAC
518 Support for the Calxeda XGMAC device
519
Ashok93fb8722012-10-15 06:20:47 +0000520 CONFIG_LAN91C96
wdenkaa603362003-05-12 21:50:16 +0000521 Support for SMSC's LAN91C96 chips.
522
wdenkaa603362003-05-12 21:50:16 +0000523 CONFIG_LAN91C96_USE_32_BIT
524 Define this to enable 32 bit addressing
525
Heiko Schocher7d037f72011-11-15 10:00:04 -0500526 CONFIG_SYS_DAVINCI_EMAC_PHY_COUNT
527 Define this if you have more then 3 PHYs.
528
Macpaul Lin199c6252010-12-21 16:59:46 +0800529 CONFIG_FTGMAC100
530 Support for Faraday's FTGMAC100 Gigabit SoC Ethernet
531
532 CONFIG_FTGMAC100_EGIGA
533 Define this to use GE link update with gigabit PHY.
534 Define this if FTGMAC100 is connected to gigabit PHY.
535 If your system has 10/100 PHY only, it might not occur
536 wrong behavior. Because PHY usually return timeout or
537 useless data when polling gigabit status and gigabit
538 control registers. This behavior won't affect the
539 correctnessof 10/100 link speed update.
540
Yoshihiro Shimodaed4cea02011-01-27 10:06:03 +0900541 CONFIG_SH_ETHER
542 Support for Renesas on-chip Ethernet controller
543
544 CONFIG_SH_ETHER_USE_PORT
545 Define the number of ports to be used
546
547 CONFIG_SH_ETHER_PHY_ADDR
548 Define the ETH PHY's address
549
Yoshihiro Shimoda281aa052011-01-27 10:06:08 +0900550 CONFIG_SH_ETHER_CACHE_WRITEBACK
551 If this option is set, the driver enables cache flush.
552
Vadim Bendeburydac69642011-10-17 08:36:14 +0000553- TPM Support:
Che-liang Chiouacea5702013-04-12 11:04:34 +0000554 CONFIG_TPM
555 Support TPM devices.
556
Christophe Ricard8759ff82015-10-06 22:54:41 +0200557 CONFIG_TPM_TIS_INFINEON
558 Support for Infineon i2c bus TPM devices. Only one device
Tom Wai-Hong Tame49fed52013-04-12 11:04:37 +0000559 per system is supported at this time.
560
Tom Wai-Hong Tame49fed52013-04-12 11:04:37 +0000561 CONFIG_TPM_TIS_I2C_BURST_LIMITATION
562 Define the burst count bytes upper limit
563
Christophe Ricard88249232016-01-21 23:27:13 +0100564 CONFIG_TPM_ST33ZP24
565 Support for STMicroelectronics TPM devices. Requires DM_TPM support.
566
567 CONFIG_TPM_ST33ZP24_I2C
568 Support for STMicroelectronics ST33ZP24 I2C devices.
569 Requires TPM_ST33ZP24 and I2C.
570
Christophe Ricard5ffadc32016-01-21 23:27:14 +0100571 CONFIG_TPM_ST33ZP24_SPI
572 Support for STMicroelectronics ST33ZP24 SPI devices.
573 Requires TPM_ST33ZP24 and SPI.
574
Dirk Eibach20489092013-06-26 15:55:15 +0200575 CONFIG_TPM_ATMEL_TWI
576 Support for Atmel TWI TPM device. Requires I2C support.
577
Che-liang Chiouacea5702013-04-12 11:04:34 +0000578 CONFIG_TPM_TIS_LPC
Vadim Bendeburydac69642011-10-17 08:36:14 +0000579 Support for generic parallel port TPM devices. Only one device
580 per system is supported at this time.
581
Reinhard Pfau4fece432013-06-26 15:55:13 +0200582 CONFIG_TPM
583 Define this to enable the TPM support library which provides
584 functional interfaces to some TPM commands.
585 Requires support for a TPM device.
586
587 CONFIG_TPM_AUTH_SESSIONS
588 Define this to enable authorized functions in the TPM library.
589 Requires CONFIG_TPM and CONFIG_SHA1.
590
wdenkc6097192002-11-03 00:24:07 +0000591- USB Support:
592 At the moment only the UHCI host controller is
Heiko Schocher6f90e582017-06-14 05:49:40 +0200593 supported (PIP405, MIP405); define
wdenkc6097192002-11-03 00:24:07 +0000594 CONFIG_USB_UHCI to enable it.
595 define CONFIG_USB_KEYBOARD to enable the USB Keyboard
wdenkfb30b4c2004-10-09 22:44:59 +0000596 and define CONFIG_USB_STORAGE to enable the USB
wdenkc6097192002-11-03 00:24:07 +0000597 storage devices.
598 Note:
599 Supported are USB Keyboards and USB Floppy drives
600 (TEAC FD-05PUB).
wdenk369d43d2004-03-14 14:09:05 +0000601
Oleksandr Tymoshenko7a881752014-02-01 21:51:25 -0700602 CONFIG_USB_DWC2_REG_ADDR the physical CPU address of the DWC2
603 HW module registers.
604
Wolfgang Denk3f0137b2006-06-14 17:45:53 +0200605- USB Device:
606 Define the below if you wish to use the USB console.
607 Once firmware is rebuilt from a serial console issue the
608 command "setenv stdin usbtty; setenv stdout usbtty" and
Marcel Ziswilerabd8dcb2008-07-09 08:17:15 +0200609 attach your USB cable. The Unix command "dmesg" should print
Wolfgang Denk3f0137b2006-06-14 17:45:53 +0200610 it has found a new device. The environment variable usbtty
611 can be set to gserial or cdc_acm to enable your device to
Wolfgang Denke2601822006-06-14 18:14:56 +0200612 appear to a USB host as a Linux gserial device or a
Wolfgang Denk3f0137b2006-06-14 17:45:53 +0200613 Common Device Class Abstract Control Model serial device.
614 If you select usbtty = gserial you should be able to enumerate
615 a Linux host by
616 # modprobe usbserial vendor=0xVendorID product=0xProductID
617 else if using cdc_acm, simply setting the environment
618 variable usbtty to be cdc_acm should suffice. The following
619 might be defined in YourBoardName.h
Wolfgang Denke2601822006-06-14 18:14:56 +0200620
Wolfgang Denke2601822006-06-14 18:14:56 +0200621 If you have a USB-IF assigned VendorID then you may wish to
Wolfgang Denk3f0137b2006-06-14 17:45:53 +0200622 define your own vendor specific values either in BoardName.h
Wolfgang Denke2601822006-06-14 18:14:56 +0200623 or directly in usbd_vendor_info.h. If you don't define
Wolfgang Denk3f0137b2006-06-14 17:45:53 +0200624 CONFIG_USBD_MANUFACTURER, CONFIG_USBD_PRODUCT_NAME,
625 CONFIG_USBD_VENDORID and CONFIG_USBD_PRODUCTID, then U-Boot
626 should pretend to be a Linux device to it's target host.
627
628 CONFIG_USBD_MANUFACTURER
629 Define this string as the name of your company for
630 - CONFIG_USBD_MANUFACTURER "my company"
Wolfgang Denke2601822006-06-14 18:14:56 +0200631
Wolfgang Denk3f0137b2006-06-14 17:45:53 +0200632 CONFIG_USBD_PRODUCT_NAME
633 Define this string as the name of your product
634 - CONFIG_USBD_PRODUCT_NAME "acme usb device"
wdenkc6097192002-11-03 00:24:07 +0000635
Wolfgang Denk3f0137b2006-06-14 17:45:53 +0200636 CONFIG_USBD_VENDORID
637 Define this as your assigned Vendor ID from the USB
638 Implementors Forum. This *must* be a genuine Vendor ID
639 to avoid polluting the USB namespace.
640 - CONFIG_USBD_VENDORID 0xFFFF
Wolfgang Denke2601822006-06-14 18:14:56 +0200641
Wolfgang Denk3f0137b2006-06-14 17:45:53 +0200642 CONFIG_USBD_PRODUCTID
643 Define this as the unique Product ID
644 for your device
645 - CONFIG_USBD_PRODUCTID 0xFFFF
Wolfgang Denke2601822006-06-14 18:14:56 +0200646
Igor Grinbergac5f6ee2011-12-12 12:08:35 +0200647- ULPI Layer Support:
648 The ULPI (UTMI Low Pin (count) Interface) PHYs are supported via
649 the generic ULPI layer. The generic layer accesses the ULPI PHY
650 via the platform viewport, so you need both the genric layer and
651 the viewport enabled. Currently only Chipidea/ARC based
652 viewport is supported.
653 To enable the ULPI layer support, define CONFIG_USB_ULPI and
654 CONFIG_USB_ULPI_VIEWPORT in your board configuration file.
Lucas Stachf31e4112012-10-01 00:44:35 +0200655 If your ULPI phy needs a different reference clock than the
656 standard 24 MHz then you have to define CONFIG_ULPI_REF_CLK to
657 the appropriate value in Hz.
wdenkc6097192002-11-03 00:24:07 +0000658
wdenk7a428cc2003-06-15 22:40:42 +0000659- MMC Support:
Yoshihiro Shimodadb7717b2011-07-04 22:21:22 +0000660 CONFIG_SH_MMCIF
661 Support for Renesas on-chip MMCIF controller
662
663 CONFIG_SH_MMCIF_ADDR
664 Define the base address of MMCIF registers
665
666 CONFIG_SH_MMCIF_CLK
667 Define the clock frequency for MMCIF
668
Tom Rini58a8d322013-03-14 05:32:47 +0000669- USB Device Firmware Update (DFU) class support:
Marek Vasut7f8d4362018-02-16 16:41:18 +0100670 CONFIG_DFU_OVER_USB
Tom Rini58a8d322013-03-14 05:32:47 +0000671 This enables the USB portion of the DFU USB class
672
Pantelis Antonioucf14d0d2013-03-14 05:32:52 +0000673 CONFIG_DFU_NAND
674 This enables support for exposing NAND devices via DFU.
675
Afzal Mohammede3c687a2013-09-18 01:15:24 +0530676 CONFIG_DFU_RAM
677 This enables support for exposing RAM via DFU.
678 Note: DFU spec refer to non-volatile memory usage, but
679 allow usages beyond the scope of spec - here RAM usage,
680 one that would help mostly the developer.
681
Heiko Schochera2f831e2013-06-12 06:05:51 +0200682 CONFIG_SYS_DFU_DATA_BUF_SIZE
683 Dfu transfer uses a buffer before writing data to the
684 raw storage device. Make the size (in bytes) of this buffer
685 configurable. The size of this buffer is also configurable
686 through the "dfu_bufsiz" environment variable.
687
Pantelis Antonioua6e788d2013-03-14 05:32:48 +0000688 CONFIG_SYS_DFU_MAX_FILE_SIZE
689 When updating files rather than the raw storage device,
690 we use a static buffer to copy the file into and then write
691 the buffer once we've been given the whole file. Define
692 this to the maximum filesize (in bytes) for the buffer.
693 Default is 4 MiB if undefined.
694
Heiko Schochere1ba1512014-03-18 08:09:56 +0100695 DFU_DEFAULT_POLL_TIMEOUT
696 Poll timeout [ms], is the timeout a device can send to the
697 host. The host must wait for this timeout before sending
698 a subsequent DFU_GET_STATUS request to the device.
699
700 DFU_MANIFEST_POLL_TIMEOUT
701 Poll timeout [ms], which the device sends to the host when
702 entering dfuMANIFEST state. Host waits this timeout, before
703 sending again an USB request to the device.
704
wdenkc6097192002-11-03 00:24:07 +0000705- Keyboard Support:
Simon Glasseaba37e2015-11-11 10:05:47 -0700706 See Kconfig help for available keyboard drivers.
707
wdenk0e2bd9c2004-06-06 21:51:03 +0000708- MII/PHY support:
wdenk0e2bd9c2004-06-06 21:51:03 +0000709 CONFIG_PHY_CLOCK_FREQ (ppc4xx)
710
711 The clock frequency of the MII bus
712
wdenk0e2bd9c2004-06-06 21:51:03 +0000713 CONFIG_PHY_CMD_DELAY (ppc4xx)
714
715 Some PHY like Intel LXT971A need extra delay after
716 command issued before MII status register can be read
717
wdenkc6097192002-11-03 00:24:07 +0000718- BOOTP Recovery Mode:
719 CONFIG_BOOTP_RANDOM_DELAY
720
721 If you have many targets in a network that try to
722 boot using BOOTP, you may want to avoid that all
723 systems send out BOOTP requests at precisely the same
724 moment (which would happen for instance at recovery
725 from a power failure, when all systems will try to
726 boot, thus flooding the BOOTP server. Defining
727 CONFIG_BOOTP_RANDOM_DELAY causes a random delay to be
728 inserted before sending out BOOTP requests. The
Wolfgang Denkb65aaf92007-08-06 23:21:05 +0200729 following delays are inserted then:
wdenkc6097192002-11-03 00:24:07 +0000730
731 1st BOOTP request: delay 0 ... 1 sec
732 2nd BOOTP request: delay 0 ... 2 sec
733 3rd BOOTP request: delay 0 ... 4 sec
734 4th and following
735 BOOTP requests: delay 0 ... 8 sec
736
Thierry Reding8977cda2014-08-19 10:21:24 +0200737 CONFIG_BOOTP_ID_CACHE_SIZE
738
739 BOOTP packets are uniquely identified using a 32-bit ID. The
740 server will copy the ID from client requests to responses and
741 U-Boot will use this to determine if it is the destination of
742 an incoming response. Some servers will check that addresses
743 aren't in use before handing them out (usually using an ARP
744 ping) and therefore take up to a few hundred milliseconds to
745 respond. Network congestion may also influence the time it
746 takes for a response to make it back to the client. If that
747 time is too long, U-Boot will retransmit requests. In order
748 to allow earlier responses to still be accepted after these
749 retransmissions, U-Boot's BOOTP client keeps a small cache of
750 IDs. The CONFIG_BOOTP_ID_CACHE_SIZE controls the size of this
751 cache. The default is to keep IDs for up to four outstanding
752 requests. Increasing this will allow U-Boot to accept offers
753 from a BOOTP client in networks with unusually high latency.
754
stroesee0aadfb2003-08-28 14:17:32 +0000755- DHCP Advanced Options:
Joe Hershberger8ca7fa02012-05-23 07:59:19 +0000756
Joe Hershbergerb35a3a62012-05-23 08:00:12 +0000757 - Link-local IP address negotiation:
758 Negotiate with other link-local clients on the local network
759 for an address that doesn't require explicit configuration.
760 This is especially useful if a DHCP server cannot be guaranteed
761 to exist in all environments that the device must operate.
762
763 See doc/README.link-local for more information.
764
Prabhakar Kushwaha2dec06f2017-11-23 16:51:32 +0530765 - MAC address from environment variables
766
767 FDT_SEQ_MACADDR_FROM_ENV
768
769 Fix-up device tree with MAC addresses fetched sequentially from
770 environment variables. This config work on assumption that
771 non-usable ethernet node of device-tree are either not present
772 or their status has been marked as "disabled".
773
wdenk145d2c12004-04-15 21:48:45 +0000774 - CDP Options:
wdenk05939202004-04-18 17:39:38 +0000775 CONFIG_CDP_DEVICE_ID
wdenk145d2c12004-04-15 21:48:45 +0000776
777 The device id used in CDP trigger frames.
778
779 CONFIG_CDP_DEVICE_ID_PREFIX
780
781 A two character string which is prefixed to the MAC address
782 of the device.
783
784 CONFIG_CDP_PORT_ID
785
786 A printf format string which contains the ascii name of
787 the port. Normally is set to "eth%d" which sets
Marcel Ziswilerabd8dcb2008-07-09 08:17:15 +0200788 eth0 for the first Ethernet, eth1 for the second etc.
wdenk145d2c12004-04-15 21:48:45 +0000789
790 CONFIG_CDP_CAPABILITIES
791
792 A 32bit integer which indicates the device capabilities;
793 0x00000010 for a normal host which does not forwards.
794
795 CONFIG_CDP_VERSION
796
797 An ascii string containing the version of the software.
798
799 CONFIG_CDP_PLATFORM
800
801 An ascii string containing the name of the platform.
802
803 CONFIG_CDP_TRIGGER
804
805 A 32bit integer sent on the trigger.
806
807 CONFIG_CDP_POWER_CONSUMPTION
808
809 A 16bit integer containing the power consumption of the
810 device in .1 of milliwatts.
811
812 CONFIG_CDP_APPLIANCE_VLAN_TYPE
813
814 A byte containing the id of the VLAN.
815
Uri Mashiach3dc6f652017-01-19 10:51:05 +0200816- Status LED: CONFIG_LED_STATUS
wdenkc6097192002-11-03 00:24:07 +0000817
818 Several configurations allow to display the current
819 status using a LED. For instance, the LED will blink
820 fast while running U-Boot code, stop blinking as
821 soon as a reply to a BOOTP request was received, and
822 start blinking slow once the Linux kernel is running
823 (supported by a status LED driver in the Linux
Uri Mashiach3dc6f652017-01-19 10:51:05 +0200824 kernel). Defining CONFIG_LED_STATUS enables this
wdenkc6097192002-11-03 00:24:07 +0000825 feature in U-Boot.
826
Igor Grinberg4997a9e2013-11-08 01:03:50 +0200827 Additional options:
828
Uri Mashiach3dc6f652017-01-19 10:51:05 +0200829 CONFIG_LED_STATUS_GPIO
Igor Grinberg4997a9e2013-11-08 01:03:50 +0200830 The status LED can be connected to a GPIO pin.
831 In such cases, the gpio_led driver can be used as a
Uri Mashiach3dc6f652017-01-19 10:51:05 +0200832 status LED backend implementation. Define CONFIG_LED_STATUS_GPIO
Igor Grinberg4997a9e2013-11-08 01:03:50 +0200833 to include the gpio_led driver in the U-Boot binary.
834
Igor Grinberg203bd9f2013-11-08 01:03:52 +0200835 CONFIG_GPIO_LED_INVERTED_TABLE
836 Some GPIO connected LEDs may have inverted polarity in which
837 case the GPIO high value corresponds to LED off state and
838 GPIO low value corresponds to LED on state.
839 In such cases CONFIG_GPIO_LED_INVERTED_TABLE may be defined
840 with a list of GPIO LEDs that have inverted polarity.
841
Tom Rini52b2e262021-08-18 23:12:24 -0400842- I2C Support:
Tom Rini0a2bac72022-11-16 13:10:29 -0500843 CFG_SYS_NUM_I2C_BUSES
Simon Glassb05e2b32016-10-02 18:01:05 -0600844 Hold the number of i2c buses you want to use.
Heiko Schochere0e55bc2012-01-16 21:12:24 +0000845
846 CONFIG_SYS_I2C_DIRECT_BUS
847 define this, if you don't use i2c muxes on your hardware.
Tom Rini6a5dccc2022-11-16 13:10:41 -0500848 if CFG_SYS_I2C_MAX_HOPS is not defined or == 0 you can
Heiko Schochere0e55bc2012-01-16 21:12:24 +0000849 omit this define.
850
Tom Rini6a5dccc2022-11-16 13:10:41 -0500851 CFG_SYS_I2C_MAX_HOPS
Heiko Schochere0e55bc2012-01-16 21:12:24 +0000852 define how many muxes are maximal consecutively connected
853 on one i2c bus. If you not use i2c muxes, omit this
854 define.
855
Tom Rini6a5dccc2022-11-16 13:10:41 -0500856 CFG_SYS_I2C_BUSES
Jeremiah Mahler03f930c2015-01-04 18:56:50 -0800857 hold a list of buses you want to use, only used if
Heiko Schochere0e55bc2012-01-16 21:12:24 +0000858 CONFIG_SYS_I2C_DIRECT_BUS is not defined, for example
Tom Rini6a5dccc2022-11-16 13:10:41 -0500859 a board with CFG_SYS_I2C_MAX_HOPS = 1 and
Tom Rini0a2bac72022-11-16 13:10:29 -0500860 CFG_SYS_NUM_I2C_BUSES = 9:
Heiko Schochere0e55bc2012-01-16 21:12:24 +0000861
Tom Rini6a5dccc2022-11-16 13:10:41 -0500862 CFG_SYS_I2C_BUSES {{0, {I2C_NULL_HOP}}, \
Heiko Schochere0e55bc2012-01-16 21:12:24 +0000863 {0, {{I2C_MUX_PCA9547, 0x70, 1}}}, \
864 {0, {{I2C_MUX_PCA9547, 0x70, 2}}}, \
865 {0, {{I2C_MUX_PCA9547, 0x70, 3}}}, \
866 {0, {{I2C_MUX_PCA9547, 0x70, 4}}}, \
867 {0, {{I2C_MUX_PCA9547, 0x70, 5}}}, \
868 {1, {I2C_NULL_HOP}}, \
869 {1, {{I2C_MUX_PCA9544, 0x72, 1}}}, \
870 {1, {{I2C_MUX_PCA9544, 0x72, 2}}}, \
871 }
872
873 which defines
874 bus 0 on adapter 0 without a mux
Heiko Schocher479a4cf2013-01-29 08:53:15 +0100875 bus 1 on adapter 0 with a PCA9547 on address 0x70 port 1
876 bus 2 on adapter 0 with a PCA9547 on address 0x70 port 2
877 bus 3 on adapter 0 with a PCA9547 on address 0x70 port 3
878 bus 4 on adapter 0 with a PCA9547 on address 0x70 port 4
879 bus 5 on adapter 0 with a PCA9547 on address 0x70 port 5
Heiko Schochere0e55bc2012-01-16 21:12:24 +0000880 bus 6 on adapter 1 without a mux
Heiko Schocher479a4cf2013-01-29 08:53:15 +0100881 bus 7 on adapter 1 with a PCA9544 on address 0x72 port 1
882 bus 8 on adapter 1 with a PCA9544 on address 0x72 port 2
Heiko Schochere0e55bc2012-01-16 21:12:24 +0000883
884 If you do not have i2c muxes on your board, omit this define.
885
Simon Glass3efce392017-05-12 21:10:00 -0600886- Legacy I2C Support:
Heiko Schocher479a4cf2013-01-29 08:53:15 +0100887 If you use the software i2c interface (CONFIG_SYS_I2C_SOFT)
wdenkb9bbd242003-06-30 16:24:52 +0000888 then the following macros need to be defined (examples are
889 from include/configs/lwmon.h):
wdenkc6097192002-11-03 00:24:07 +0000890
891 I2C_INIT
892
wdenkb9bbd242003-06-30 16:24:52 +0000893 (Optional). Any commands necessary to enable the I2C
wdenk4a5c8a72003-03-06 00:02:04 +0000894 controller or configure ports.
wdenkc6097192002-11-03 00:24:07 +0000895
wdenk544e9732004-02-06 23:19:44 +0000896 eg: #define I2C_INIT (immr->im_cpm.cp_pbdir |= PB_SCL)
wdenkb9bbd242003-06-30 16:24:52 +0000897
wdenkc6097192002-11-03 00:24:07 +0000898 I2C_ACTIVE
899
900 The code necessary to make the I2C data line active
901 (driven). If the data line is open collector, this
902 define can be null.
903
wdenkb9bbd242003-06-30 16:24:52 +0000904 eg: #define I2C_ACTIVE (immr->im_cpm.cp_pbdir |= PB_SDA)
905
wdenkc6097192002-11-03 00:24:07 +0000906 I2C_TRISTATE
907
908 The code necessary to make the I2C data line tri-stated
909 (inactive). If the data line is open collector, this
910 define can be null.
911
wdenkb9bbd242003-06-30 16:24:52 +0000912 eg: #define I2C_TRISTATE (immr->im_cpm.cp_pbdir &= ~PB_SDA)
913
wdenkc6097192002-11-03 00:24:07 +0000914 I2C_READ
915
York Sun4a598092013-04-01 11:29:11 -0700916 Code that returns true if the I2C data line is high,
917 false if it is low.
wdenkc6097192002-11-03 00:24:07 +0000918
wdenkb9bbd242003-06-30 16:24:52 +0000919 eg: #define I2C_READ ((immr->im_cpm.cp_pbdat & PB_SDA) != 0)
920
wdenkc6097192002-11-03 00:24:07 +0000921 I2C_SDA(bit)
922
York Sun4a598092013-04-01 11:29:11 -0700923 If <bit> is true, sets the I2C data line high. If it
924 is false, it clears it (low).
wdenkc6097192002-11-03 00:24:07 +0000925
wdenkb9bbd242003-06-30 16:24:52 +0000926 eg: #define I2C_SDA(bit) \
wdenk2bb11052003-07-17 23:16:40 +0000927 if(bit) immr->im_cpm.cp_pbdat |= PB_SDA; \
wdenk544e9732004-02-06 23:19:44 +0000928 else immr->im_cpm.cp_pbdat &= ~PB_SDA
wdenkb9bbd242003-06-30 16:24:52 +0000929
wdenkc6097192002-11-03 00:24:07 +0000930 I2C_SCL(bit)
931
York Sun4a598092013-04-01 11:29:11 -0700932 If <bit> is true, sets the I2C clock line high. If it
933 is false, it clears it (low).
wdenkc6097192002-11-03 00:24:07 +0000934
wdenkb9bbd242003-06-30 16:24:52 +0000935 eg: #define I2C_SCL(bit) \
wdenk2bb11052003-07-17 23:16:40 +0000936 if(bit) immr->im_cpm.cp_pbdat |= PB_SCL; \
wdenk544e9732004-02-06 23:19:44 +0000937 else immr->im_cpm.cp_pbdat &= ~PB_SCL
wdenkb9bbd242003-06-30 16:24:52 +0000938
wdenkc6097192002-11-03 00:24:07 +0000939 I2C_DELAY
940
941 This delay is invoked four times per clock cycle so this
942 controls the rate of data transfer. The data rate thus
wdenkb9bbd242003-06-30 16:24:52 +0000943 is 1 / (I2C_DELAY * 4). Often defined to be something
wdenk21136db2003-07-16 21:53:01 +0000944 like:
945
wdenkb9bbd242003-06-30 16:24:52 +0000946 #define I2C_DELAY udelay(2)
wdenkc6097192002-11-03 00:24:07 +0000947
Mike Frysingeree12d542010-07-21 13:38:02 -0400948 CONFIG_SOFT_I2C_GPIO_SCL / CONFIG_SOFT_I2C_GPIO_SDA
949
950 If your arch supports the generic GPIO framework (asm/gpio.h),
951 then you may alternatively define the two GPIOs that are to be
952 used as SCL / SDA. Any of the previous I2C_xxx macros will
953 have GPIO-based defaults assigned to them as appropriate.
954
955 You should define these to the GPIO value as given directly to
956 the generic GPIO functions.
957
Tom Rini8227d052022-12-04 10:04:08 -0500958 CFG_I2C_MULTI_BUS
Ben Warren45657152006-09-07 16:50:54 -0400959
960 This option allows the use of multiple I2C buses, each of which
Wolfgang Denk092ae952011-10-26 10:21:21 +0000961 must have a controller. At any point in time, only one bus is
962 active. To switch to a different bus, use the 'i2c dev' command.
Ben Warren45657152006-09-07 16:50:54 -0400963 Note that bus numbering is zero-based.
964
Tom Rini6a5dccc2022-11-16 13:10:41 -0500965 CFG_SYS_I2C_NOPROBES
Ben Warren45657152006-09-07 16:50:54 -0400966
967 This option specifies a list of I2C devices that will be skipped
Tom Rini6da96a12022-12-02 16:42:30 -0500968 when the 'i2c probe' command is issued.
Ben Warren45657152006-09-07 16:50:54 -0400969
970 e.g.
Tom Rini6a5dccc2022-11-16 13:10:41 -0500971 #define CFG_SYS_I2C_NOPROBES {0x50,0x68}
Ben Warren45657152006-09-07 16:50:54 -0400972
973 will skip addresses 0x50 and 0x68 on a board with one I2C bus
974
Tom Rini6a5dccc2022-11-16 13:10:41 -0500975 CFG_SYS_RTC_BUS_NUM
Stefan Roese096cc9b2007-02-20 10:51:26 +0100976
977 If defined, then this indicates the I2C bus number for the RTC.
978 If not defined, then U-Boot assumes that RTC is on I2C bus 0.
979
Andrew Dyer58c41f92008-12-29 17:36:01 -0600980 CONFIG_SOFT_I2C_READ_REPEATED_START
981
982 defining this will force the i2c_read() function in
983 the soft_i2c driver to perform an I2C repeated start
984 between writing the address pointer and reading the
985 data. If this define is omitted the default behaviour
986 of doing a stop-start sequence will be used. Most I2C
987 devices can use either method, but some require one or
988 the other.
Timur Tabiab347542006-11-03 19:15:00 -0600989
wdenkc6097192002-11-03 00:24:07 +0000990- SPI Support: CONFIG_SPI
991
992 Enables SPI driver (so far only tested with
993 SPI EEPROM, also an instance works with Crystal A/D and
994 D/As on the SACSng board)
995
Heiko Schocherb77c8882014-07-14 10:22:11 +0200996 CONFIG_SYS_SPI_MXC_WAIT
997 Timeout for waiting until spi transfer completed.
998 default: (CONFIG_SYS_HZ/100) /* 10 ms */
999
Matthias Fuchsa4400872007-12-27 17:12:34 +01001000- FPGA Support: CONFIG_FPGA
wdenkc6097192002-11-03 00:24:07 +00001001
Matthias Fuchsa4400872007-12-27 17:12:34 +01001002 Enables FPGA subsystem.
1003
1004 CONFIG_FPGA_<vendor>
1005
1006 Enables support for specific chip vendors.
1007 (ALTERA, XILINX)
wdenkc6097192002-11-03 00:24:07 +00001008
Matthias Fuchsa4400872007-12-27 17:12:34 +01001009 CONFIG_FPGA_<family>
wdenkc6097192002-11-03 00:24:07 +00001010
Matthias Fuchsa4400872007-12-27 17:12:34 +01001011 Enables support for FPGA family.
1012 (SPARTAN2, SPARTAN3, VIRTEX2, CYCLONE2, ACEX1K, ACEX)
1013
Jean-Christophe PLAGNIOL-VILLARD03836942008-10-16 15:01:15 +02001014 CONFIG_SYS_FPGA_CHECK_BUSY
wdenkc6097192002-11-03 00:24:07 +00001015
wdenk4a5c8a72003-03-06 00:02:04 +00001016 Enable checks on FPGA configuration interface busy
1017 status by the configuration function. This option
1018 will require a board or device specific function to
1019 be written.
wdenkc6097192002-11-03 00:24:07 +00001020
Tom Rini88d86ec2022-12-04 10:03:57 -05001021 CFG_FPGA_DELAY
wdenkc6097192002-11-03 00:24:07 +00001022
1023 If defined, a function that provides delays in the FPGA
1024 configuration driver.
1025
Jean-Christophe PLAGNIOL-VILLARD03836942008-10-16 15:01:15 +02001026 CONFIG_SYS_FPGA_CHECK_ERROR
wdenkc6097192002-11-03 00:24:07 +00001027
wdenk4a5c8a72003-03-06 00:02:04 +00001028 Check for configuration errors during FPGA bitfile
1029 loading. For example, abort during Virtex II
1030 configuration if the INIT_B line goes low (which
1031 indicated a CRC error).
wdenkc6097192002-11-03 00:24:07 +00001032
Tom Rini6a5dccc2022-11-16 13:10:41 -05001033 CFG_SYS_FPGA_WAIT_INIT
wdenkc6097192002-11-03 00:24:07 +00001034
Jeremiah Mahler03f930c2015-01-04 18:56:50 -08001035 Maximum time to wait for the INIT_B line to de-assert
1036 after PROB_B has been de-asserted during a Virtex II
wdenk4a5c8a72003-03-06 00:02:04 +00001037 FPGA configuration sequence. The default time is 500
Marcel Ziswilerabd8dcb2008-07-09 08:17:15 +02001038 ms.
wdenkc6097192002-11-03 00:24:07 +00001039
Tom Rini6a5dccc2022-11-16 13:10:41 -05001040 CFG_SYS_FPGA_WAIT_BUSY
wdenkc6097192002-11-03 00:24:07 +00001041
Jeremiah Mahler03f930c2015-01-04 18:56:50 -08001042 Maximum time to wait for BUSY to de-assert during
Marcel Ziswilerabd8dcb2008-07-09 08:17:15 +02001043 Virtex II FPGA configuration. The default is 5 ms.
wdenkc6097192002-11-03 00:24:07 +00001044
Tom Rini6a5dccc2022-11-16 13:10:41 -05001045 CFG_SYS_FPGA_WAIT_CONFIG
wdenkc6097192002-11-03 00:24:07 +00001046
wdenk4a5c8a72003-03-06 00:02:04 +00001047 Time to wait after FPGA configuration. The default is
Marcel Ziswilerabd8dcb2008-07-09 08:17:15 +02001048 200 ms.
wdenkc6097192002-11-03 00:24:07 +00001049
wdenkc6097192002-11-03 00:24:07 +00001050- Vendor Parameter Protection:
1051
wdenk4a5c8a72003-03-06 00:02:04 +00001052 U-Boot considers the values of the environment
1053 variables "serial#" (Board Serial Number) and
wdenkeb20ad32003-09-05 23:19:14 +00001054 "ethaddr" (Ethernet Address) to be parameters that
wdenk4a5c8a72003-03-06 00:02:04 +00001055 are set once by the board vendor / manufacturer, and
1056 protects these variables from casual modification by
1057 the user. Once set, these variables are read-only,
1058 and write or delete attempts are rejected. You can
Marcel Ziswilerabd8dcb2008-07-09 08:17:15 +02001059 change this behaviour:
wdenkc6097192002-11-03 00:24:07 +00001060
1061 If CONFIG_ENV_OVERWRITE is #defined in your config
1062 file, the write protection for vendor parameters is
wdenkcc1e2562003-03-06 13:39:27 +00001063 completely disabled. Anybody can change or delete
wdenkc6097192002-11-03 00:24:07 +00001064 these parameters.
1065
Joe Hershberger71497d02012-12-11 22:16:31 -06001066 The same can be accomplished in a more flexible way
1067 for any variable by configuring the type of access
1068 to allow for those variables in the ".flags" variable
Tom Rini0297e5f2022-12-04 10:03:40 -05001069 or define CFG_ENV_FLAGS_LIST_STATIC.
Joe Hershberger71497d02012-12-11 22:16:31 -06001070
wdenkc6097192002-11-03 00:24:07 +00001071- Protected RAM:
1072 CONFIG_PRAM
1073
1074 Define this variable to enable the reservation of
1075 "protected RAM", i. e. RAM which is not overwritten
1076 by U-Boot. Define CONFIG_PRAM to hold the number of
1077 kB you want to reserve for pRAM. You can overwrite
1078 this default value by defining an environment
1079 variable "pram" to the number of kB you want to
1080 reserve. Note that the board info structure will
1081 still show the full amount of RAM. If pRAM is
1082 reserved, a new environment variable "mem" will
1083 automatically be defined to hold the amount of
1084 remaining RAM in a form that can be passed as boot
1085 argument to Linux, for instance like that:
1086
Wolfgang Denk86eb3b72005-11-20 21:40:11 +01001087 setenv bootargs ... mem=\${mem}
wdenkc6097192002-11-03 00:24:07 +00001088 saveenv
1089
1090 This way you can tell Linux not to use this memory,
1091 either, which results in a memory region that will
1092 not be affected by reboots.
1093
1094 *WARNING* If your board configuration uses automatic
1095 detection of the RAM size, you must make sure that
1096 this memory test is non-destructive. So far, the
1097 following board configurations are known to be
1098 "pRAM-clean":
1099
Heiko Schocher65d94db2017-06-07 17:33:09 +02001100 IVMS8, IVML24, SPD8xx,
Wolfgang Denk90326762012-10-24 02:36:15 +00001101 HERMES, IP860, RPXlite, LWMON,
Heiko Schocher71cb3e92017-06-07 17:33:10 +02001102 FLAGADM
wdenkc6097192002-11-03 00:24:07 +00001103
1104- Error Recovery:
wdenkc6097192002-11-03 00:24:07 +00001105 Note:
1106
wdenk57b2d802003-06-27 21:31:46 +00001107 In the current implementation, the local variables
1108 space and global environment variables space are
1109 separated. Local variables are those you define by
1110 simply typing `name=value'. To access a local
1111 variable later on, you have write `$name' or
1112 `${name}'; to execute the contents of a variable
1113 directly type `$name' at the command prompt.
wdenkc6097192002-11-03 00:24:07 +00001114
wdenk4a5c8a72003-03-06 00:02:04 +00001115 Global environment variables are those you use
1116 setenv/printenv to work with. To run a command stored
1117 in such a variable, you need to use the run command,
1118 and you must not use the '$' sign to access them.
wdenkc6097192002-11-03 00:24:07 +00001119
1120 To store commands and special characters in a
1121 variable, please use double quotation marks
1122 surrounding the whole text of the variable, instead
1123 of the backslashes before semicolons and special
1124 symbols.
1125
wdenkc0aa5c52003-12-06 19:49:23 +00001126- Default Environment:
Tom Rinic9edebe2022-12-04 10:03:50 -05001127 CFG_EXTRA_ENV_SETTINGS
wdenkc6097192002-11-03 00:24:07 +00001128
wdenk4a5c8a72003-03-06 00:02:04 +00001129 Define this to contain any number of null terminated
1130 strings (variable = value pairs) that will be part of
wdenkeb20ad32003-09-05 23:19:14 +00001131 the default environment compiled into the boot image.
wdenk591dda52002-11-18 00:14:45 +00001132
wdenk4a5c8a72003-03-06 00:02:04 +00001133 For example, place something like this in your
1134 board's config file:
wdenkc6097192002-11-03 00:24:07 +00001135
Tom Rinic9edebe2022-12-04 10:03:50 -05001136 #define CFG_EXTRA_ENV_SETTINGS \
wdenkc6097192002-11-03 00:24:07 +00001137 "myvar1=value1\0" \
1138 "myvar2=value2\0"
1139
wdenk4a5c8a72003-03-06 00:02:04 +00001140 Warning: This method is based on knowledge about the
1141 internal format how the environment is stored by the
1142 U-Boot code. This is NOT an official, exported
1143 interface! Although it is unlikely that this format
wdenkeb20ad32003-09-05 23:19:14 +00001144 will change soon, there is no guarantee either.
wdenkc6097192002-11-03 00:24:07 +00001145 You better know what you are doing here.
1146
wdenk4a5c8a72003-03-06 00:02:04 +00001147 Note: overly (ab)use of the default environment is
1148 discouraged. Make sure to check other ways to preset
Wolfgang Denk85c25df2009-04-01 23:34:12 +02001149 the environment like the "source" command or the
wdenk4a5c8a72003-03-06 00:02:04 +00001150 boot command first.
wdenkc6097192002-11-03 00:24:07 +00001151
Simon Glass6b8d5fd2012-11-30 13:01:17 +00001152 CONFIG_DELAY_ENVIRONMENT
1153
1154 Normally the environment is loaded when the board is
Jeremiah Mahler03f930c2015-01-04 18:56:50 -08001155 initialised so that it is available to U-Boot. This inhibits
Simon Glass6b8d5fd2012-11-30 13:01:17 +00001156 that so that the environment is not available until
1157 explicitly loaded later by U-Boot code. With CONFIG_OF_CONTROL
1158 this is instead controlled by the value of
1159 /config/load-environment.
1160
Detlev Zundel0ecb6112009-12-01 17:16:19 +01001161- Automatic software updates via TFTP server
1162 CONFIG_UPDATE_TFTP
1163 CONFIG_UPDATE_TFTP_CNT_MAX
1164 CONFIG_UPDATE_TFTP_MSEC_MAX
1165
1166 These options enable and control the auto-update feature;
1167 for a more detailed description refer to doc/README.update.
1168
1169- MTD Support (mtdparts command, UBI support)
Heiko Schocherf5895d12014-06-24 10:10:04 +02001170 CONFIG_MTD_UBI_WL_THRESHOLD
1171 This parameter defines the maximum difference between the highest
1172 erase counter value and the lowest erase counter value of eraseblocks
1173 of UBI devices. When this threshold is exceeded, UBI starts performing
1174 wear leveling by means of moving data from eraseblock with low erase
1175 counter to eraseblocks with high erase counter.
1176
1177 The default value should be OK for SLC NAND flashes, NOR flashes and
1178 other flashes which have eraseblock life-cycle 100000 or more.
1179 However, in case of MLC NAND flashes which typically have eraseblock
1180 life-cycle less than 10000, the threshold should be lessened (e.g.,
1181 to 128 or 256, although it does not have to be power of 2).
1182
1183 default: 4096
Simon Glass6c0be912014-10-23 18:58:54 -06001184
Heiko Schocherf5895d12014-06-24 10:10:04 +02001185 CONFIG_MTD_UBI_BEB_LIMIT
1186 This option specifies the maximum bad physical eraseblocks UBI
1187 expects on the MTD device (per 1024 eraseblocks). If the
1188 underlying flash does not admit of bad eraseblocks (e.g. NOR
1189 flash), this value is ignored.
1190
1191 NAND datasheets often specify the minimum and maximum NVM
1192 (Number of Valid Blocks) for the flashes' endurance lifetime.
1193 The maximum expected bad eraseblocks per 1024 eraseblocks
1194 then can be calculated as "1024 * (1 - MinNVB / MaxNVB)",
1195 which gives 20 for most NANDs (MaxNVB is basically the total
1196 count of eraseblocks on the chip).
1197
1198 To put it differently, if this value is 20, UBI will try to
1199 reserve about 1.9% of physical eraseblocks for bad blocks
1200 handling. And that will be 1.9% of eraseblocks on the entire
1201 NAND chip, not just the MTD partition UBI attaches. This means
1202 that if you have, say, a NAND flash chip admits maximum 40 bad
1203 eraseblocks, and it is split on two MTD partitions of the same
1204 size, UBI will reserve 40 eraseblocks when attaching a
1205 partition.
1206
1207 default: 20
1208
1209 CONFIG_MTD_UBI_FASTMAP
1210 Fastmap is a mechanism which allows attaching an UBI device
1211 in nearly constant time. Instead of scanning the whole MTD device it
1212 only has to locate a checkpoint (called fastmap) on the device.
1213 The on-flash fastmap contains all information needed to attach
1214 the device. Using fastmap makes only sense on large devices where
1215 attaching by scanning takes long. UBI will not automatically install
1216 a fastmap on old images, but you can set the UBI parameter
1217 CONFIG_MTD_UBI_FASTMAP_AUTOCONVERT to 1 if you want so. Please note
1218 that fastmap-enabled images are still usable with UBI implementations
1219 without fastmap support. On typical flash devices the whole fastmap
1220 fits into one PEB. UBI will reserve PEBs to hold two fastmaps.
1221
1222 CONFIG_MTD_UBI_FASTMAP_AUTOCONVERT
1223 Set this parameter to enable fastmap automatically on images
1224 without a fastmap.
1225 default: 0
1226
Heiko Schocher94b66de2015-10-22 06:19:21 +02001227 CONFIG_MTD_UBI_FM_DEBUG
1228 Enable UBI fastmap debug
1229 default: 0
1230
Daniel Schwierzeck39ca08e2011-07-18 07:48:07 +00001231- SPL framework
Wolfgang Denk825223d2011-09-11 21:24:09 +02001232 CONFIG_SPL
1233 Enable building of SPL globally.
Daniel Schwierzeck39ca08e2011-07-18 07:48:07 +00001234
Albert ARIBAUD \(3ADEV\)287b0942015-03-31 11:40:50 +02001235 CONFIG_SPL_PANIC_ON_RAW_IMAGE
1236 When defined, SPL will panic() if the image it has
1237 loaded does not have a signature.
1238 Defining this is useful when code which loads images
1239 in SPL cannot guarantee that absolutely all read errors
1240 will be caught.
1241 An example is the LPC32XX MLC NAND driver, which will
1242 consider that a completely unreadable NAND block is bad,
1243 and thus should be skipped silently.
1244
Tom Rinife3b0c72012-08-13 11:37:56 -07001245 CONFIG_SPL_DISPLAY_PRINT
1246 For ARM, enable an optional function to print more information
1247 about the running system.
1248
Scott Wood2b36fbb2012-12-06 13:33:17 +00001249 CONFIG_SPL_MPC83XX_WAIT_FOR_NAND
1250 Set this for NAND SPL on PPC mpc83xx targets, so that
1251 start.S waits for the rest of the SPL to load before
1252 continuing (the hardware starts execution after just
1253 loading the first page rather than the full 4K).
1254
Thomas Gleixner820d24d2016-07-12 20:28:12 +02001255 CONFIG_SPL_UBI
1256 Support for a lightweight UBI (fastmap) scanner and
1257 loader
1258
Tom Rini36853852012-02-14 07:29:40 +00001259 CONFIG_SYS_NAND_5_ADDR_CYCLE, CONFIG_SYS_NAND_PAGE_COUNT,
1260 CONFIG_SYS_NAND_PAGE_SIZE, CONFIG_SYS_NAND_OOBSIZE,
1261 CONFIG_SYS_NAND_BLOCK_SIZE, CONFIG_SYS_NAND_BAD_BLOCK_POS,
Tom Rinib4213492022-11-12 17:36:51 -05001262 CFG_SYS_NAND_ECCPOS, CFG_SYS_NAND_ECCSIZE,
1263 CFG_SYS_NAND_ECCBYTES
Tom Rini36853852012-02-14 07:29:40 +00001264 Defines the size and behavior of the NAND that SPL uses
Scott Wood36c440e2012-09-21 18:35:27 -05001265 to read U-Boot
Tom Rini36853852012-02-14 07:29:40 +00001266
Tom Rinib4213492022-11-12 17:36:51 -05001267 CFG_SYS_NAND_U_BOOT_DST
Scott Wood36c440e2012-09-21 18:35:27 -05001268 Location in memory to load U-Boot to
1269
Tom Rinib4213492022-11-12 17:36:51 -05001270 CFG_SYS_NAND_U_BOOT_SIZE
Scott Wood36c440e2012-09-21 18:35:27 -05001271 Size of image to load
Tom Rini36853852012-02-14 07:29:40 +00001272
Tom Rinib4213492022-11-12 17:36:51 -05001273 CFG_SYS_NAND_U_BOOT_START
Scott Wood36c440e2012-09-21 18:35:27 -05001274 Entry point in loaded image to jump to
Tom Rini36853852012-02-14 07:29:40 +00001275
Pavel Machekde997252012-08-30 22:42:11 +02001276 CONFIG_SPL_RAM_DEVICE
1277 Support for running image already present in ram, in SPL binary
1278
Marek Vasut9f2e0eb2018-05-13 00:22:52 +02001279 CONFIG_SPL_FIT_PRINT
Simon Glass82d94532013-05-08 08:05:59 +00001280 Printing information about a FIT image adds quite a bit of
1281 code to SPL. So this is normally disabled in SPL. Use this
1282 option to re-enable it. This will affect the output of the
1283 bootm command when booting a FIT image.
1284
wdenkc0aa5c52003-12-06 19:49:23 +00001285- Interrupt support (PPC):
1286
wdenk1ebf41e2004-01-02 14:00:00 +00001287 There are common interrupt_init() and timer_interrupt()
1288 for all PPC archs. interrupt_init() calls interrupt_init_cpu()
Marcel Ziswilerabd8dcb2008-07-09 08:17:15 +02001289 for CPU specific initialization. interrupt_init_cpu()
wdenk1ebf41e2004-01-02 14:00:00 +00001290 should set decrementer_count to appropriate value. If
Marcel Ziswilerabd8dcb2008-07-09 08:17:15 +02001291 CPU resets decrementer automatically after interrupt
wdenk1ebf41e2004-01-02 14:00:00 +00001292 (ppc4xx) it should set decrementer_count to zero.
Marcel Ziswilerabd8dcb2008-07-09 08:17:15 +02001293 timer_interrupt() calls timer_interrupt_cpu() for CPU
wdenk1ebf41e2004-01-02 14:00:00 +00001294 specific handling. If board has watchdog / status_led
1295 / other_activity_monitor it works automatically from
1296 general timer_interrupt().
wdenkc0aa5c52003-12-06 19:49:23 +00001297
wdenkc6097192002-11-03 00:24:07 +00001298
Helmut Raigerd5a184b2011-10-20 04:19:47 +00001299Board initialization settings:
1300------------------------------
1301
1302During Initialization u-boot calls a number of board specific functions
1303to allow the preparation of board specific prerequisites, e.g. pin setup
1304before drivers are initialized. To enable these callbacks the
1305following configuration macros have to be defined. Currently this is
1306architecture specific, so please check arch/your_architecture/lib/board.c
1307typically in board_init_f() and board_init_r().
1308
1309- CONFIG_BOARD_EARLY_INIT_F: Call board_early_init_f()
1310- CONFIG_BOARD_EARLY_INIT_R: Call board_early_init_r()
1311- CONFIG_BOARD_LATE_INIT: Call board_late_init()
wdenkc6097192002-11-03 00:24:07 +00001312
wdenkc6097192002-11-03 00:24:07 +00001313Configuration Settings:
1314-----------------------
1315
Simon Glass8927bf22019-12-28 10:45:10 -07001316- MEM_SUPPORT_64BIT_DATA: Defined automatically if compiled as 64-bit.
York Sun6c480012014-02-26 17:03:19 -08001317 Optionally it can be defined to support 64-bit memory commands.
1318
Jean-Christophe PLAGNIOL-VILLARD03836942008-10-16 15:01:15 +02001319- CONFIG_SYS_LONGHELP: Defined when you want long help messages included;
wdenkc6097192002-11-03 00:24:07 +00001320 undefine this when you're short of memory.
1321
Peter Tyserdfb72b82009-01-27 18:03:12 -06001322- CONFIG_SYS_HELP_CMD_WIDTH: Defined when you want to override the default
1323 width of the commands listed in the 'help' command output.
1324
Jean-Christophe PLAGNIOL-VILLARD03836942008-10-16 15:01:15 +02001325- CONFIG_SYS_PROMPT: This is what U-Boot prints on the console to
wdenkc6097192002-11-03 00:24:07 +00001326 prompt for user input.
1327
Tom Rini6a5dccc2022-11-16 13:10:41 -05001328- CFG_SYS_BAUDRATE_TABLE:
wdenkc6097192002-11-03 00:24:07 +00001329 List of legal baudrate settings for this board.
1330
Tom Rini6a5dccc2022-11-16 13:10:41 -05001331- CFG_SYS_MEM_RESERVE_SECURE
York Sun1ef95cc2016-06-24 16:46:18 -07001332 Only implemented for ARMv8 for now.
Tom Rini6a5dccc2022-11-16 13:10:41 -05001333 If defined, the size of CFG_SYS_MEM_RESERVE_SECURE memory
York Sun5d286cd2015-12-04 11:57:07 -08001334 is substracted from total RAM and won't be reported to OS.
1335 This memory can be used as secure memory. A variable
York Sun1ef95cc2016-06-24 16:46:18 -07001336 gd->arch.secure_ram is used to track the location. In systems
York Sun5d286cd2015-12-04 11:57:07 -08001337 the RAM base is not zero, or RAM is divided into banks,
1338 this variable needs to be recalcuated to get the address.
1339
Tom Rinibb4dd962022-11-16 13:10:37 -05001340- CFG_SYS_SDRAM_BASE:
wdenkc6097192002-11-03 00:24:07 +00001341 Physical start address of SDRAM. _Must_ be 0 here.
1342
Tom Rini6a5dccc2022-11-16 13:10:41 -05001343- CFG_SYS_FLASH_BASE:
wdenkc6097192002-11-03 00:24:07 +00001344 Physical start address of Flash memory.
1345
Jean-Christophe PLAGNIOL-VILLARD03836942008-10-16 15:01:15 +02001346- CONFIG_SYS_MALLOC_LEN:
wdenkc6097192002-11-03 00:24:07 +00001347 Size of DRAM reserved for malloc() use.
1348
Simon Glass863e4042014-07-10 22:23:28 -06001349- CONFIG_SYS_MALLOC_F_LEN
1350 Size of the malloc() pool for use before relocation. If
1351 this is defined, then a very simple malloc() implementation
1352 will become available before relocation. The address is just
1353 below the global data, and the stack is moved down to make
1354 space.
1355
1356 This feature allocates regions with increasing addresses
1357 within the region. calloc() is supported, but realloc()
1358 is not available. free() is supported but does nothing.
Jeremiah Mahler03f930c2015-01-04 18:56:50 -08001359 The memory will be freed (or in fact just forgotten) when
Simon Glass863e4042014-07-10 22:23:28 -06001360 U-Boot relocates itself.
1361
Simon Glass9fa901b2014-11-10 17:16:54 -07001362- CONFIG_SYS_MALLOC_SIMPLE
1363 Provides a simple and small malloc() and calloc() for those
1364 boards which do not use the full malloc in SPL (which is
Tom Rini166e3222022-05-27 12:48:32 -04001365 enabled with CONFIG_SYS_SPL_MALLOC).
Simon Glass9fa901b2014-11-10 17:16:54 -07001366
Tom Rini6a5dccc2022-11-16 13:10:41 -05001367- CFG_SYS_BOOTMAPSZ:
wdenkc6097192002-11-03 00:24:07 +00001368 Maximum size of memory mapped by the startup code of
1369 the Linux kernel; all data that must be processed by
Bartlomiej Siekac5648c82008-04-14 15:44:16 +02001370 the Linux kernel (bd_info, boot arguments, FDT blob if
1371 used) must be put below this limit, unless "bootm_low"
Robert P. J. Day832d36e2013-09-16 07:15:45 -04001372 environment variable is defined and non-zero. In such case
Bartlomiej Siekac5648c82008-04-14 15:44:16 +02001373 all data for the Linux kernel must be between "bootm_low"
Tom Rini6a5dccc2022-11-16 13:10:41 -05001374 and "bootm_low" + CFG_SYS_BOOTMAPSZ. The environment
Grant Likely26396382011-03-28 09:58:43 +00001375 variable "bootm_mapsize" will override the value of
Tom Rini6a5dccc2022-11-16 13:10:41 -05001376 CFG_SYS_BOOTMAPSZ. If CFG_SYS_BOOTMAPSZ is undefined,
Grant Likely26396382011-03-28 09:58:43 +00001377 then the value in "bootm_size" will be used instead.
wdenkc6097192002-11-03 00:24:07 +00001378
John Rigbyeea8e692010-10-13 13:57:35 -06001379- CONFIG_SYS_BOOT_GET_CMDLINE:
1380 Enables allocating and saving kernel cmdline in space between
1381 "bootm_low" and "bootm_low" + BOOTMAPSZ.
1382
1383- CONFIG_SYS_BOOT_GET_KBD:
1384 Enables allocating and saving a kernel copy of the bd_info in
1385 space between "bootm_low" and "bootm_low" + BOOTMAPSZ.
1386
Jean-Christophe PLAGNIOL-VILLARD03836942008-10-16 15:01:15 +02001387- CONFIG_SYS_FLASH_PROTECTION
wdenkdccbda02003-07-14 22:13:32 +00001388 If defined, hardware flash sectors protection is used
1389 instead of U-Boot software protection.
1390
Jean-Christophe PLAGNIOL-VILLARD03836942008-10-16 15:01:15 +02001391- CONFIG_SYS_FLASH_CFI:
wdenk4a5c8a72003-03-06 00:02:04 +00001392 Define if the flash driver uses extra elements in the
wdenk2cefd152004-02-08 22:55:38 +00001393 common flash structure for storing flash geometry.
1394
Jean-Christophe PLAGNIOL-VILLARD8d94c232008-08-13 01:40:42 +02001395- CONFIG_FLASH_CFI_DRIVER
wdenk2cefd152004-02-08 22:55:38 +00001396 This option also enables the building of the cfi_flash driver
1397 in the drivers directory
wdenkc6097192002-11-03 00:24:07 +00001398
Piotr Ziecik3e939e92008-11-17 15:57:58 +01001399- CONFIG_FLASH_CFI_MTD
1400 This option enables the building of the cfi_mtd driver
1401 in the drivers directory. The driver exports CFI flash
1402 to the MTD layer.
1403
Jean-Christophe PLAGNIOL-VILLARD03836942008-10-16 15:01:15 +02001404- CONFIG_SYS_FLASH_USE_BUFFER_WRITE
Guennadi Liakhovetski183284f2008-04-03 13:36:02 +02001405 Use buffered writes to flash.
1406
Joe Hershberger71497d02012-12-11 22:16:31 -06001407- CONFIG_ENV_FLAGS_LIST_DEFAULT
Tom Rini0297e5f2022-12-04 10:03:40 -05001408- CFG_ENV_FLAGS_LIST_STATIC
Robert P. J. Day832d36e2013-09-16 07:15:45 -04001409 Enable validation of the values given to environment variables when
Joe Hershberger71497d02012-12-11 22:16:31 -06001410 calling env set. Variables can be restricted to only decimal,
1411 hexadecimal, or boolean. If CONFIG_CMD_NET is also defined,
1412 the variables can also be restricted to IP address or MAC address.
1413
1414 The format of the list is:
1415 type_attribute = [s|d|x|b|i|m]
Jeremiah Mahler03f930c2015-01-04 18:56:50 -08001416 access_attribute = [a|r|o|c]
1417 attributes = type_attribute[access_attribute]
Joe Hershberger71497d02012-12-11 22:16:31 -06001418 entry = variable_name[:attributes]
1419 list = entry[,list]
1420
1421 The type attributes are:
1422 s - String (default)
1423 d - Decimal
1424 x - Hexadecimal
1425 b - Boolean ([1yYtT|0nNfF])
1426 i - IP address
1427 m - MAC address
1428
Joe Hershberger6fe26c92012-12-11 22:16:34 -06001429 The access attributes are:
1430 a - Any (default)
1431 r - Read-only
1432 o - Write-once
1433 c - Change-default
1434
Joe Hershberger71497d02012-12-11 22:16:31 -06001435 - CONFIG_ENV_FLAGS_LIST_DEFAULT
1436 Define this to a list (string) to define the ".flags"
Jeremiah Mahler03f930c2015-01-04 18:56:50 -08001437 environment variable in the default or embedded environment.
Joe Hershberger71497d02012-12-11 22:16:31 -06001438
Tom Rini0297e5f2022-12-04 10:03:40 -05001439 - CFG_ENV_FLAGS_LIST_STATIC
Joe Hershberger71497d02012-12-11 22:16:31 -06001440 Define this to a list (string) to define validation that
1441 should be done if an entry is not found in the ".flags"
1442 environment variable. To override a setting in the static
1443 list, simply add an entry for the same variable name to the
1444 ".flags" variable.
1445
Joe Hershberger6db9fd42015-05-20 14:27:20 -05001446 If CONFIG_REGEX is defined, the variable_name above is evaluated as a
1447 regular expression. This allows multiple variables to define the same
1448 flags without explicitly listing them for each variable.
1449
wdenkc6097192002-11-03 00:24:07 +00001450The following definitions that deal with the placement and management
1451of environment data (variable area); in general, we support the
1452following configurations:
1453
wdenkc6097192002-11-03 00:24:07 +00001454BE CAREFUL! The first access to the environment happens quite early
Jeremiah Mahler03f930c2015-01-04 18:56:50 -08001455in U-Boot initialization (when we try to get the setting of for the
Marcel Ziswilerabd8dcb2008-07-09 08:17:15 +02001456console baudrate). You *MUST* have mapped your NVRAM area then, or
wdenkc6097192002-11-03 00:24:07 +00001457U-Boot will hang.
1458
1459Please note that even with NVRAM we still use a copy of the
1460environment in RAM: we could work on NVRAM directly, but we want to
1461keep settings there always unmodified except somebody uses "saveenv"
1462to save the current settings.
1463
Liu Gang85bcd732012-03-08 00:33:20 +00001464BE CAREFUL! For some special cases, the local device can not use
1465"saveenv" command. For example, the local device will get the
Liu Gang357bf5a2012-08-09 05:10:01 +00001466environment stored in a remote NOR flash by SRIO or PCIE link,
1467but it can not erase, write this NOR flash by SRIO or PCIE interface.
Liu Gang85bcd732012-03-08 00:33:20 +00001468
Guennadi Liakhovetskifad24442009-05-18 16:07:22 +02001469- CONFIG_NAND_ENV_DST
1470
1471 Defines address in RAM to which the nand_spl code should copy the
1472 environment. If redundant environment is used, it will be copied to
1473 CONFIG_NAND_ENV_DST + CONFIG_ENV_SIZE.
1474
Bruce Adleredecc942007-11-02 13:15:42 -07001475Please note that the environment is read-only until the monitor
wdenkc6097192002-11-03 00:24:07 +00001476has been relocated to RAM and a RAM copy of the environment has been
Simon Glass64b723f2017-08-03 12:22:12 -06001477created; also, when using EEPROM you will have to use env_get_f()
wdenkc6097192002-11-03 00:24:07 +00001478until then to read environment variables.
1479
wdenk8dba0502003-03-31 16:34:49 +00001480The environment is protected by a CRC32 checksum. Before the monitor
1481is relocated into RAM, as a result of a bad CRC you will be working
1482with the compiled-in default environment - *silently*!!! [This is
1483necessary, because the first environment variable we need is the
1484"baudrate" setting for the console - if we have a bad CRC, we don't
1485have any device yet where we could complain.]
wdenkc6097192002-11-03 00:24:07 +00001486
1487Note: once the monitor has been relocated, then it will complain if
1488the default environment is used; a new CRC is computed as soon as you
wdenk8dba0502003-03-31 16:34:49 +00001489use the "saveenv" command to store a valid environment.
wdenkc6097192002-11-03 00:24:07 +00001490
Jean-Christophe PLAGNIOL-VILLARD03836942008-10-16 15:01:15 +02001491- CONFIG_SYS_FAULT_MII_ADDR:
wdenk9c53f402003-10-15 23:53:47 +00001492 MII address of the PHY to check for the Ethernet link state.
wdenkc6097192002-11-03 00:24:07 +00001493
Simon Glass28a9e332012-11-30 13:01:18 +00001494- CONFIG_DISPLAY_BOARDINFO
1495 Display information about the board that U-Boot is running on
1496 when U-Boot starts up. The board function checkboard() is called
1497 to do this.
1498
Simon Glasse8822012012-11-30 13:01:19 +00001499- CONFIG_DISPLAY_BOARDINFO_LATE
1500 Similar to the previous option, but display this information
1501 later, once stdio is running and output goes to the LCD, if
1502 present.
1503
wdenkc6097192002-11-03 00:24:07 +00001504Low Level (hardware related) configuration options:
wdenkc8434db2003-03-26 06:55:25 +00001505---------------------------------------------------
wdenkc6097192002-11-03 00:24:07 +00001506
Jean-Christophe PLAGNIOL-VILLARD03836942008-10-16 15:01:15 +02001507- CONFIG_SYS_CACHELINE_SIZE:
wdenkc6097192002-11-03 00:24:07 +00001508 Cache Line Size of the CPU.
1509
Timur Tabid8f341c2011-08-04 18:03:41 -05001510- CONFIG_SYS_CCSRBAR_DEFAULT:
1511 Default (power-on reset) physical address of CCSR on Freescale
1512 PowerPC SOCs.
1513
Tom Rini6a5dccc2022-11-16 13:10:41 -05001514- CFG_SYS_CCSRBAR:
Timur Tabid8f341c2011-08-04 18:03:41 -05001515 Virtual address of CCSR. On a 32-bit build, this is typically
1516 the same value as CONFIG_SYS_CCSRBAR_DEFAULT.
1517
Tom Rini6a5dccc2022-11-16 13:10:41 -05001518- CFG_SYS_CCSRBAR_PHYS:
Timur Tabid8f341c2011-08-04 18:03:41 -05001519 Physical address of CCSR. CCSR can be relocated to a new
1520 physical address, if desired. In this case, this macro should
Wolfgang Denk092ae952011-10-26 10:21:21 +00001521 be set to that address. Otherwise, it should be set to the
Timur Tabid8f341c2011-08-04 18:03:41 -05001522 same value as CONFIG_SYS_CCSRBAR_DEFAULT. For example, CCSR
1523 is typically relocated on 36-bit builds. It is recommended
1524 that this macro be defined via the _HIGH and _LOW macros:
1525
Tom Rini6a5dccc2022-11-16 13:10:41 -05001526 #define CFG_SYS_CCSRBAR_PHYS ((CFG_SYS_CCSRBAR_PHYS_HIGH
1527 * 1ull) << 32 | CFG_SYS_CCSRBAR_PHYS_LOW)
Timur Tabid8f341c2011-08-04 18:03:41 -05001528
Tom Rini6a5dccc2022-11-16 13:10:41 -05001529- CFG_SYS_CCSRBAR_PHYS_HIGH:
1530 Bits 33-36 of CFG_SYS_CCSRBAR_PHYS. This value is typically
Wolfgang Denkd590fb12011-10-07 09:58:21 +02001531 either 0 (32-bit build) or 0xF (36-bit build). This macro is
Timur Tabid8f341c2011-08-04 18:03:41 -05001532 used in assembly code, so it must not contain typecasts or
1533 integer size suffixes (e.g. "ULL").
1534
Tom Rini6a5dccc2022-11-16 13:10:41 -05001535- CFG_SYS_CCSRBAR_PHYS_LOW:
1536 Lower 32-bits of CFG_SYS_CCSRBAR_PHYS. This macro is
Timur Tabid8f341c2011-08-04 18:03:41 -05001537 used in assembly code, so it must not contain typecasts or
1538 integer size suffixes (e.g. "ULL").
1539
Jean-Christophe PLAGNIOL-VILLARD03836942008-10-16 15:01:15 +02001540- CONFIG_SYS_IMMR: Physical address of the Internal Memory.
wdenk07d7e6b2004-12-16 21:44:03 +00001541 DO NOT CHANGE unless you know exactly what you're
Christophe Leroy069fa832017-07-06 10:23:22 +02001542 doing! (11-4) [MPC8xx systems only]
wdenkc6097192002-11-03 00:24:07 +00001543
Tom Rini6a5dccc2022-11-16 13:10:41 -05001544- CFG_SYS_INIT_RAM_ADDR:
wdenkc6097192002-11-03 00:24:07 +00001545
wdenkeb20ad32003-09-05 23:19:14 +00001546 Start address of memory area that can be used for
wdenkc6097192002-11-03 00:24:07 +00001547 initial data and stack; please note that this must be
1548 writable memory that is working WITHOUT special
1549 initialization, i. e. you CANNOT use normal RAM which
1550 will become available only after programming the
1551 memory controller and running certain initialization
1552 sequences.
1553
1554 U-Boot uses the following memory types:
Christophe Leroy069fa832017-07-06 10:23:22 +02001555 - MPC8xx: IMMR (internal memory of the CPU)
wdenkc6097192002-11-03 00:24:07 +00001556
Jean-Christophe PLAGNIOL-VILLARD03836942008-10-16 15:01:15 +02001557- CONFIG_SYS_SCCR: System Clock and reset Control Register (15-27)
wdenkc6097192002-11-03 00:24:07 +00001558
Jean-Christophe PLAGNIOL-VILLARD03836942008-10-16 15:01:15 +02001559- CONFIG_SYS_OR_TIMING_SDRAM:
wdenkc6097192002-11-03 00:24:07 +00001560 SDRAM timing
1561
Kumar Gala8975d7a2010-12-30 12:09:53 -06001562- CONFIG_SYS_SRIOn_MEM_VIRT:
1563 Virtual Address of SRIO port 'n' memory region
1564
Simon Glass970b61e2019-11-14 12:57:09 -07001565- CONFIG_SYS_SRIOn_MEM_PHYxS:
Kumar Gala8975d7a2010-12-30 12:09:53 -06001566 Physical Address of SRIO port 'n' memory region
1567
1568- CONFIG_SYS_SRIOn_MEM_SIZE:
1569 Size of SRIO port 'n' memory region
1570
Fabio Estevamf17e8782013-04-11 09:35:34 +00001571- CONFIG_SYS_NAND_BUSWIDTH_16BIT
1572 Defined to tell the NAND controller that the NAND chip is using
1573 a 16 bit bus.
1574 Not all NAND drivers use this symbol.
Fabio Estevam417052b2013-04-11 09:35:35 +00001575 Example of drivers that use it:
Miquel Raynal1f1ae152018-08-16 17:30:07 +02001576 - drivers/mtd/nand/raw/ndfc.c
1577 - drivers/mtd/nand/raw/mxc_nand.c
Alex Watermancd6aae32011-05-19 15:08:36 -04001578
1579- CONFIG_SYS_NDFC_EBC0_CFG
1580 Sets the EBC0_CFG register for the NDFC. If not defined
1581 a default value will be used.
1582
Jean-Christophe PLAGNIOL-VILLARD03836942008-10-16 15:01:15 +02001583- CONFIG_SYS_SPD_BUS_NUM
Wolfgang Denkb240aef2008-03-26 10:40:12 +01001584 If SPD EEPROM is on an I2C bus other than the first
1585 one, specify here. Note that the value must resolve
1586 to something your driver can deal with.
Ben Warren45657152006-09-07 16:50:54 -04001587
York Sunbd495cf2011-09-16 13:21:35 -07001588- CONFIG_FSL_DDR_INTERACTIVE
1589 Enable interactive DDR debugging. See doc/README.fsl-ddr.
1590
York Sun8ced0502015-01-06 13:18:55 -08001591- CONFIG_FSL_DDR_SYNC_REFRESH
1592 Enable sync of refresh for multiple controllers.
1593
York Sunb6a35f82015-03-19 09:30:28 -07001594- CONFIG_FSL_DDR_BIST
1595 Enable built-in memory test for Freescale DDR controllers.
1596
wdenk6203e402004-04-18 10:13:26 +00001597- CONFIG_RMII
1598 Enable RMII mode for all FECs.
1599 Note that this is a global option, we can't
1600 have one FEC in standard MII mode and another in RMII mode.
1601
wdenk20c98a62004-04-23 20:32:05 +00001602- CONFIG_CRC32_VERIFY
1603 Add a verify option to the crc32 command.
1604 The syntax is:
1605
1606 => crc32 -v <address> <count> <crc32>
1607
1608 Where address/count indicate a memory area
1609 and crc32 is the correct crc32 which the
1610 area should have.
1611
wdenk64519362004-07-11 17:40:54 +00001612- CONFIG_LOOPW
1613 Add the "loopw" memory command. This only takes effect if
Simon Glass92ffdee2017-08-04 16:34:27 -06001614 the memory commands are activated globally (CONFIG_CMD_MEMORY).
wdenk64519362004-07-11 17:40:54 +00001615
Joel Johnsondb5a97e2020-01-29 09:17:18 -07001616- CONFIG_CMD_MX_CYCLIC
stroesecc3af832004-12-16 18:46:55 +00001617 Add the "mdc" and "mwc" memory commands. These are cyclic
1618 "md/mw" commands.
1619 Examples:
1620
wdenk07d7e6b2004-12-16 21:44:03 +00001621 => mdc.b 10 4 500
stroesecc3af832004-12-16 18:46:55 +00001622 This command will print 4 bytes (10,11,12,13) each 500 ms.
1623
wdenk07d7e6b2004-12-16 21:44:03 +00001624 => mwc.l 100 12345678 10
stroesecc3af832004-12-16 18:46:55 +00001625 This command will write 12345678 to address 100 all 10 ms.
1626
wdenk07d7e6b2004-12-16 21:44:03 +00001627 This only takes effect if the memory commands are activated
Simon Glass92ffdee2017-08-04 16:34:27 -06001628 globally (CONFIG_CMD_MEMORY).
stroesecc3af832004-12-16 18:46:55 +00001629
Aneesh V552a3192011-07-13 05:11:07 +00001630- CONFIG_SPL_BUILD
Thomas Hebbfd37f242019-11-13 18:18:03 -08001631 Set when the currently-running compilation is for an artifact
1632 that will end up in the SPL (as opposed to the TPL or U-Boot
1633 proper). Code that needs stage-specific behavior should check
1634 this.
wdenk336b2bc2005-04-02 23:52:25 +00001635
Ying Zhang2d2e3b62013-08-16 15:16:15 +08001636- CONFIG_TPL_BUILD
Thomas Hebbfd37f242019-11-13 18:18:03 -08001637 Set when the currently-running compilation is for an artifact
1638 that will end up in the TPL (as opposed to the SPL or U-Boot
1639 proper). Code that needs stage-specific behavior should check
1640 this.
Ying Zhang2d2e3b62013-08-16 15:16:15 +08001641
Simon Glass17dabf02013-02-24 17:33:14 +00001642- CONFIG_ARCH_MAP_SYSMEM
1643 Generally U-Boot (and in particular the md command) uses
1644 effective address. It is therefore not necessary to regard
1645 U-Boot address as virtual addresses that need to be translated
1646 to physical addresses. However, sandbox requires this, since
1647 it maintains its own little RAM buffer which contains all
1648 addressable memory. This option causes some memory accesses
1649 to be mapped through map_sysmem() / unmap_sysmem().
1650
Simon Glassbfb59802013-02-14 04:18:54 +00001651- CONFIG_X86_RESET_VECTOR
1652 If defined, the x86 reset vector code is included. This is not
1653 needed when U-Boot is running from Coreboot.
Gabe Black14f82462012-11-27 21:08:06 +00001654
Timur Tabi275f4bb2011-11-22 09:21:25 -06001655Freescale QE/FMAN Firmware Support:
1656-----------------------------------
1657
1658The Freescale QUICCEngine (QE) and Frame Manager (FMAN) both support the
1659loading of "firmware", which is encoded in the QE firmware binary format.
1660This firmware often needs to be loaded during U-Boot booting, so macros
1661are used to identify the storage device (NOR flash, SPI, etc) and the address
1662within that device.
1663
Zhao Qiang83a90842014-03-21 16:21:44 +08001664- CONFIG_SYS_FMAN_FW_ADDR
1665 The address in the storage device where the FMAN microcode is located. The
Tom Rinifa911f82019-05-12 07:59:12 -04001666 meaning of this address depends on which CONFIG_SYS_QE_FMAN_FW_IN_xxx macro
Zhao Qiang83a90842014-03-21 16:21:44 +08001667 is also specified.
1668
1669- CONFIG_SYS_QE_FW_ADDR
1670 The address in the storage device where the QE microcode is located. The
Tom Rinifa911f82019-05-12 07:59:12 -04001671 meaning of this address depends on which CONFIG_SYS_QE_FMAN_FW_IN_xxx macro
Timur Tabi275f4bb2011-11-22 09:21:25 -06001672 is also specified.
1673
1674- CONFIG_SYS_QE_FMAN_FW_LENGTH
1675 The maximum possible size of the firmware. The firmware binary format
1676 has a field that specifies the actual size of the firmware, but it
1677 might not be possible to read any part of the firmware unless some
1678 local storage is allocated to hold the entire firmware first.
1679
1680- CONFIG_SYS_QE_FMAN_FW_IN_NOR
1681 Specifies that QE/FMAN firmware is located in NOR flash, mapped as
1682 normal addressable memory via the LBC. CONFIG_SYS_FMAN_FW_ADDR is the
1683 virtual address in NOR flash.
1684
1685- CONFIG_SYS_QE_FMAN_FW_IN_NAND
1686 Specifies that QE/FMAN firmware is located in NAND flash.
1687 CONFIG_SYS_FMAN_FW_ADDR is the offset within NAND flash.
1688
1689- CONFIG_SYS_QE_FMAN_FW_IN_MMC
1690 Specifies that QE/FMAN firmware is located on the primary SD/MMC
1691 device. CONFIG_SYS_FMAN_FW_ADDR is the byte offset on that device.
1692
Liu Gang1e084582012-03-08 00:33:18 +00001693- CONFIG_SYS_QE_FMAN_FW_IN_REMOTE
1694 Specifies that QE/FMAN firmware is located in the remote (master)
1695 memory space. CONFIG_SYS_FMAN_FW_ADDR is a virtual address which
Liu Gang357bf5a2012-08-09 05:10:01 +00001696 can be mapped from slave TLB->slave LAW->slave SRIO or PCIE outbound
1697 window->master inbound window->master LAW->the ucode address in
1698 master's memory space.
Timur Tabi275f4bb2011-11-22 09:21:25 -06001699
J. German Rivera8ff14b72014-06-23 15:15:55 -07001700Freescale Layerscape Management Complex Firmware Support:
1701---------------------------------------------------------
1702The Freescale Layerscape Management Complex (MC) supports the loading of
1703"firmware".
1704This firmware often needs to be loaded during U-Boot booting, so macros
1705are used to identify the storage device (NOR flash, SPI, etc) and the address
1706within that device.
1707
1708- CONFIG_FSL_MC_ENET
1709 Enable the MC driver for Layerscape SoCs.
1710
Prabhakar Kushwaha853a9012015-06-02 10:55:52 +05301711Freescale Layerscape Debug Server Support:
1712-------------------------------------------
1713The Freescale Layerscape Debug Server Support supports the loading of
1714"Debug Server firmware" and triggering SP boot-rom.
1715This firmware often needs to be loaded during U-Boot booting.
1716
York Sun928b6812015-12-07 11:08:58 -08001717- CONFIG_SYS_MC_RSV_MEM_ALIGN
1718 Define alignment of reserved memory MC requires
Prabhakar Kushwaha853a9012015-06-02 10:55:52 +05301719
Paul Kocialkowski7b917022015-07-26 18:48:15 +02001720Reproducible builds
1721-------------------
1722
1723In order to achieve reproducible builds, timestamps used in the U-Boot build
1724process have to be set to a fixed value.
1725
1726This is done using the SOURCE_DATE_EPOCH environment variable.
1727SOURCE_DATE_EPOCH is to be set on the build host's shell, not as a configuration
1728option for U-Boot or an environment variable in U-Boot.
1729
1730SOURCE_DATE_EPOCH should be set to a number of seconds since the epoch, in UTC.
1731
wdenkc6097192002-11-03 00:24:07 +00001732Building the Software:
1733======================
1734
Wolfgang Denkb240aef2008-03-26 10:40:12 +01001735Building U-Boot has been tested in several native build environments
1736and in many different cross environments. Of course we cannot support
1737all possibly existing versions of cross development tools in all
1738(potentially obsolete) versions. In case of tool chain problems we
Naoki Hayamae0cc1852020-10-08 13:17:16 +09001739recommend to use the ELDK (see https://www.denx.de/wiki/DULG/ELDK)
Wolfgang Denkb240aef2008-03-26 10:40:12 +01001740which is extensively used to build and test U-Boot.
wdenkc6097192002-11-03 00:24:07 +00001741
Wolfgang Denkb240aef2008-03-26 10:40:12 +01001742If you are not using a native environment, it is assumed that you
1743have GNU cross compiling tools available in your path. In this case,
1744you must set the environment variable CROSS_COMPILE in your shell.
1745Note that no changes to the Makefile or any other source files are
1746necessary. For example using the ELDK on a 4xx CPU, please enter:
wdenkc6097192002-11-03 00:24:07 +00001747
Wolfgang Denkb240aef2008-03-26 10:40:12 +01001748 $ CROSS_COMPILE=ppc_4xx-
1749 $ export CROSS_COMPILE
wdenkc6097192002-11-03 00:24:07 +00001750
Wolfgang Denkb240aef2008-03-26 10:40:12 +01001751U-Boot is intended to be simple to build. After installing the
1752sources you must configure U-Boot for one specific board type. This
wdenkc6097192002-11-03 00:24:07 +00001753is done by typing:
1754
Holger Freyther7ba4e572014-08-04 09:26:05 +02001755 make NAME_defconfig
wdenkc6097192002-11-03 00:24:07 +00001756
Holger Freyther7ba4e572014-08-04 09:26:05 +02001757where "NAME_defconfig" is the name of one of the existing configu-
Heinrich Schuchardtd6e07af2020-02-24 18:36:30 +01001758rations; see configs/*_defconfig for supported names.
wdenk2f0812d2003-10-08 22:45:44 +00001759
Heinrich Schuchardtd6e07af2020-02-24 18:36:30 +01001760Note: for some boards special configuration names may exist; check if
wdenk6c59edc2004-05-03 20:45:30 +00001761 additional information is available from the board vendor; for
1762 instance, the TQM823L systems are available without (standard)
1763 or with LCD support. You can select such additional "features"
Marcel Ziswilerabd8dcb2008-07-09 08:17:15 +02001764 when choosing the configuration, i. e.
wdenkc6097192002-11-03 00:24:07 +00001765
Holger Freyther7ba4e572014-08-04 09:26:05 +02001766 make TQM823L_defconfig
wdenk6c59edc2004-05-03 20:45:30 +00001767 - will configure for a plain TQM823L, i. e. no LCD support
wdenkc6097192002-11-03 00:24:07 +00001768
Holger Freyther7ba4e572014-08-04 09:26:05 +02001769 make TQM823L_LCD_defconfig
wdenk6c59edc2004-05-03 20:45:30 +00001770 - will configure for a TQM823L with U-Boot console on LCD
wdenkc6097192002-11-03 00:24:07 +00001771
wdenk6c59edc2004-05-03 20:45:30 +00001772 etc.
wdenkc6097192002-11-03 00:24:07 +00001773
wdenkc6097192002-11-03 00:24:07 +00001774
wdenk6c59edc2004-05-03 20:45:30 +00001775Finally, type "make all", and you should get some working U-Boot
1776images ready for download to / installation on your system:
wdenkc6097192002-11-03 00:24:07 +00001777
wdenk6c59edc2004-05-03 20:45:30 +00001778- "u-boot.bin" is a raw binary image
1779- "u-boot" is an image in ELF binary format
1780- "u-boot.srec" is in Motorola S-Record format
wdenkc6097192002-11-03 00:24:07 +00001781
Marian Balakowiczefe063f2006-09-07 17:25:40 +02001782By default the build is performed locally and the objects are saved
1783in the source directory. One of the two methods can be used to change
1784this behavior and build U-Boot to some external directory:
1785
17861. Add O= to the make command line invocations:
1787
1788 make O=/tmp/build distclean
Holger Freyther7ba4e572014-08-04 09:26:05 +02001789 make O=/tmp/build NAME_defconfig
Marian Balakowiczefe063f2006-09-07 17:25:40 +02001790 make O=/tmp/build all
1791
Timo Ketolac8c67602014-11-06 14:39:05 +020017922. Set environment variable KBUILD_OUTPUT to point to the desired location:
Marian Balakowiczefe063f2006-09-07 17:25:40 +02001793
Timo Ketolac8c67602014-11-06 14:39:05 +02001794 export KBUILD_OUTPUT=/tmp/build
Marian Balakowiczefe063f2006-09-07 17:25:40 +02001795 make distclean
Holger Freyther7ba4e572014-08-04 09:26:05 +02001796 make NAME_defconfig
Marian Balakowiczefe063f2006-09-07 17:25:40 +02001797 make all
1798
Timo Ketolac8c67602014-11-06 14:39:05 +02001799Note that the command line "O=" setting overrides the KBUILD_OUTPUT environment
Marian Balakowiczefe063f2006-09-07 17:25:40 +02001800variable.
1801
Daniel Schwierzeck88484422018-01-26 16:31:04 +01001802User specific CPPFLAGS, AFLAGS and CFLAGS can be passed to the compiler by
1803setting the according environment variables KCPPFLAGS, KAFLAGS and KCFLAGS.
1804For example to treat all compiler warnings as errors:
1805
1806 make KCFLAGS=-Werror
wdenkc6097192002-11-03 00:24:07 +00001807
wdenk6c59edc2004-05-03 20:45:30 +00001808Please be aware that the Makefiles assume you are using GNU make, so
1809for instance on NetBSD you might need to use "gmake" instead of
1810native "make".
wdenkc6097192002-11-03 00:24:07 +00001811
wdenkc6097192002-11-03 00:24:07 +00001812
wdenk6c59edc2004-05-03 20:45:30 +00001813If the system board that you have is not listed, then you will need
1814to port U-Boot to your hardware platform. To do this, follow these
1815steps:
wdenkc6097192002-11-03 00:24:07 +00001816
Phil Sutterc77b4882015-12-25 14:41:18 +010018171. Create a new directory to hold your board specific code. Add any
wdenk6c59edc2004-05-03 20:45:30 +00001818 files you need. In your board directory, you will need at least
Phil Sutterc77b4882015-12-25 14:41:18 +01001819 the "Makefile" and a "<board>.c".
18202. Create a new configuration file "include/configs/<board>.h" for
1821 your board.
wdenk6c59edc2004-05-03 20:45:30 +000018223. If you're porting U-Boot to a new CPU, then also create a new
1823 directory to hold your CPU specific code. Add any files you need.
Holger Freyther7ba4e572014-08-04 09:26:05 +020018244. Run "make <board>_defconfig" with your new name.
wdenk6c59edc2004-05-03 20:45:30 +000018255. Type "make", and you should get a working "u-boot.srec" file
1826 to be installed on your target system.
18276. Debug and solve any problems that might arise.
1828 [Of course, this last step is much harder than it sounds.]
wdenkc6097192002-11-03 00:24:07 +00001829
wdenkc6097192002-11-03 00:24:07 +00001830
wdenk6c59edc2004-05-03 20:45:30 +00001831Testing of U-Boot Modifications, Ports to New Hardware, etc.:
1832==============================================================
wdenkc6097192002-11-03 00:24:07 +00001833
Wolfgang Denkb240aef2008-03-26 10:40:12 +01001834If you have modified U-Boot sources (for instance added a new board
1835or support for new devices, a new CPU, etc.) you are expected to
wdenk6c59edc2004-05-03 20:45:30 +00001836provide feedback to the other developers. The feedback normally takes
Thomas Hebbfd37f242019-11-13 18:18:03 -08001837the form of a "patch", i.e. a context diff against a certain (latest
Wolfgang Denkb240aef2008-03-26 10:40:12 +01001838official or latest in the git repository) version of U-Boot sources.
wdenkc6097192002-11-03 00:24:07 +00001839
Wolfgang Denkb240aef2008-03-26 10:40:12 +01001840But before you submit such a patch, please verify that your modifi-
1841cation did not break existing code. At least make sure that *ALL* of
wdenk6c59edc2004-05-03 20:45:30 +00001842the supported boards compile WITHOUT ANY compiler warnings. To do so,
Simon Glassdc27def2016-07-27 20:33:08 -06001843just run the buildman script (tools/buildman/buildman), which will
1844configure and build U-Boot for ALL supported system. Be warned, this
1845will take a while. Please see the buildman README, or run 'buildman -H'
1846for documentation.
wdenkc6097192002-11-03 00:24:07 +00001847
Marian Balakowiczefe063f2006-09-07 17:25:40 +02001848
wdenk6c59edc2004-05-03 20:45:30 +00001849See also "U-Boot Porting Guide" below.
wdenkc6097192002-11-03 00:24:07 +00001850
wdenkc6097192002-11-03 00:24:07 +00001851
wdenk6c59edc2004-05-03 20:45:30 +00001852Monitor Commands - Overview:
1853============================
wdenkc6097192002-11-03 00:24:07 +00001854
wdenk6c59edc2004-05-03 20:45:30 +00001855go - start application at address 'addr'
1856run - run commands in an environment variable
1857bootm - boot application image from memory
1858bootp - boot image via network using BootP/TFTP protocol
Marek Vasutcf41a9b2012-03-14 21:52:45 +00001859bootz - boot zImage from memory
wdenk6c59edc2004-05-03 20:45:30 +00001860tftpboot- boot image via network using TFTP protocol
1861 and env variables "ipaddr" and "serverip"
1862 (and eventually "gatewayip")
Simon Glass6a398d22011-10-24 18:00:07 +00001863tftpput - upload a file via network using TFTP protocol
wdenk6c59edc2004-05-03 20:45:30 +00001864rarpboot- boot image via network using RARP/TFTP protocol
1865diskboot- boot from IDE devicebootd - boot default, i.e., run 'bootcmd'
1866loads - load S-Record file over serial line
1867loadb - load binary file over serial line (kermit mode)
Rui Miguel Silva433f15a2022-05-11 10:55:40 +01001868loadm - load binary blob from source address to destination address
wdenk6c59edc2004-05-03 20:45:30 +00001869md - memory display
1870mm - memory modify (auto-incrementing)
1871nm - memory modify (constant address)
1872mw - memory write (fill)
Simon Glass19038de2020-06-02 19:26:49 -06001873ms - memory search
wdenk6c59edc2004-05-03 20:45:30 +00001874cp - memory copy
1875cmp - memory compare
1876crc32 - checksum calculation
Peter Tyser469cde42009-04-18 22:34:03 -05001877i2c - I2C sub-system
wdenk6c59edc2004-05-03 20:45:30 +00001878sspi - SPI utility commands
1879base - print or set address offset
1880printenv- print environment variables
Pragnesh Patel1d5955f2020-12-22 11:30:05 +05301881pwm - control pwm channels
wdenk6c59edc2004-05-03 20:45:30 +00001882setenv - set environment variables
1883saveenv - save environment variables to persistent storage
1884protect - enable or disable FLASH write protection
1885erase - erase FLASH memory
1886flinfo - print FLASH memory information
Karl O. Pinc4baf03d2012-08-03 05:57:21 +00001887nand - NAND memory operations (see doc/README.nand)
wdenk6c59edc2004-05-03 20:45:30 +00001888bdinfo - print Board Info structure
1889iminfo - print header information for application image
1890coninfo - print console devices and informations
1891ide - IDE sub-system
1892loop - infinite loop on address range
wdenk64519362004-07-11 17:40:54 +00001893loopw - infinite write loop on address range
wdenk6c59edc2004-05-03 20:45:30 +00001894mtest - simple RAM test
1895icache - enable or disable instruction cache
1896dcache - enable or disable data cache
1897reset - Perform RESET of the CPU
1898echo - echo args to console
1899version - print monitor version
1900help - print online help
1901? - alias for 'help'
wdenkc6097192002-11-03 00:24:07 +00001902
wdenkc6097192002-11-03 00:24:07 +00001903
wdenk6c59edc2004-05-03 20:45:30 +00001904Monitor Commands - Detailed Description:
1905========================================
wdenkc6097192002-11-03 00:24:07 +00001906
wdenk6c59edc2004-05-03 20:45:30 +00001907TODO.
wdenkc6097192002-11-03 00:24:07 +00001908
wdenk6c59edc2004-05-03 20:45:30 +00001909For now: just type "help <command>".
wdenkc6097192002-11-03 00:24:07 +00001910
1911
wdenk6c59edc2004-05-03 20:45:30 +00001912Note for Redundant Ethernet Interfaces:
1913=======================================
wdenkf4688a22003-05-28 08:06:31 +00001914
Marcel Ziswilerabd8dcb2008-07-09 08:17:15 +02001915Some boards come with redundant Ethernet interfaces; U-Boot supports
wdenk6c59edc2004-05-03 20:45:30 +00001916such configurations and is capable of automatic selection of a
1917"working" interface when needed. MAC assignment works as follows:
wdenkf4688a22003-05-28 08:06:31 +00001918
wdenk6c59edc2004-05-03 20:45:30 +00001919Network interfaces are numbered eth0, eth1, eth2, ... Corresponding
1920MAC addresses can be stored in the environment as "ethaddr" (=>eth0),
1921"eth1addr" (=>eth1), "eth2addr", ...
wdenkf4688a22003-05-28 08:06:31 +00001922
wdenk6c59edc2004-05-03 20:45:30 +00001923If the network interface stores some valid MAC address (for instance
1924in SROM), this is used as default address if there is NO correspon-
1925ding setting in the environment; if the corresponding environment
1926variable is set, this overrides the settings in the card; that means:
wdenkf4688a22003-05-28 08:06:31 +00001927
wdenk6c59edc2004-05-03 20:45:30 +00001928o If the SROM has a valid MAC address, and there is no address in the
1929 environment, the SROM's address is used.
wdenkc6097192002-11-03 00:24:07 +00001930
wdenk6c59edc2004-05-03 20:45:30 +00001931o If there is no valid address in the SROM, and a definition in the
1932 environment exists, then the value from the environment variable is
1933 used.
wdenkc6097192002-11-03 00:24:07 +00001934
wdenk6c59edc2004-05-03 20:45:30 +00001935o If both the SROM and the environment contain a MAC address, and
1936 both addresses are the same, this MAC address is used.
wdenkc6097192002-11-03 00:24:07 +00001937
wdenk6c59edc2004-05-03 20:45:30 +00001938o If both the SROM and the environment contain a MAC address, and the
1939 addresses differ, the value from the environment is used and a
1940 warning is printed.
wdenkc6097192002-11-03 00:24:07 +00001941
wdenk6c59edc2004-05-03 20:45:30 +00001942o If neither SROM nor the environment contain a MAC address, an error
Joe Hershberger2dc2b5d2015-05-04 14:55:13 -05001943 is raised. If CONFIG_NET_RANDOM_ETHADDR is defined, then in this case
1944 a random, locally-assigned MAC is used.
wdenkc6097192002-11-03 00:24:07 +00001945
Ben Warren6db991a2010-04-26 11:11:46 -07001946If Ethernet drivers implement the 'write_hwaddr' function, valid MAC addresses
Wolfgang Denk092ae952011-10-26 10:21:21 +00001947will be programmed into hardware as part of the initialization process. This
Ben Warren6db991a2010-04-26 11:11:46 -07001948may be skipped by setting the appropriate 'ethmacskip' environment variable.
1949The naming convention is as follows:
1950"ethmacskip" (=>eth0), "eth1macskip" (=>eth1) etc.
wdenkc6097192002-11-03 00:24:07 +00001951
wdenk6c59edc2004-05-03 20:45:30 +00001952Image Formats:
1953==============
wdenkc6097192002-11-03 00:24:07 +00001954
Marian Balakowicz18710b82008-03-12 12:13:13 +01001955U-Boot is capable of booting (and performing other auxiliary operations on)
1956images in two formats:
1957
1958New uImage format (FIT)
1959-----------------------
1960
1961Flexible and powerful format based on Flattened Image Tree -- FIT (similar
1962to Flattened Device Tree). It allows the use of images with multiple
1963components (several kernels, ramdisks, etc.), with contents protected by
1964SHA1, MD5 or CRC32. More details are found in the doc/uImage.FIT directory.
1965
1966
1967Old uImage format
1968-----------------
1969
1970Old image format is based on binary files which can be basically anything,
1971preceded by a special header; see the definitions in include/image.h for
1972details; basically, the header defines the following image properties:
wdenkc6097192002-11-03 00:24:07 +00001973
wdenk6c59edc2004-05-03 20:45:30 +00001974* Target Operating System (Provisions for OpenBSD, NetBSD, FreeBSD,
1975 4.4BSD, Linux, SVR4, Esix, Solaris, Irix, SCO, Dell, NCR, VxWorks,
Peter Tyser56b8dd12008-09-08 14:56:49 -05001976 LynxOS, pSOS, QNX, RTEMS, INTEGRITY;
Thomas Huthc90d56a2021-11-13 18:13:50 +01001977 Currently supported: Linux, NetBSD, VxWorks, QNX, RTEMS, INTEGRITY).
Andy Shevchenko8cb5cdd2017-07-05 16:25:22 +03001978* Target CPU Architecture (Provisions for Alpha, ARM, Intel x86,
Tom Rini53320122022-04-06 09:21:25 -04001979 IA64, MIPS, Nios II, PowerPC, IBM S390, SuperH, Sparc, Sparc 64 Bit;
1980 Currently supported: ARM, Intel x86, MIPS, Nios II, PowerPC).
wdenk6c59edc2004-05-03 20:45:30 +00001981* Compression Type (uncompressed, gzip, bzip2)
1982* Load Address
1983* Entry Point
1984* Image Name
1985* Image Timestamp
wdenkc6097192002-11-03 00:24:07 +00001986
wdenk6c59edc2004-05-03 20:45:30 +00001987The header is marked by a special Magic Number, and both the header
1988and the data portions of the image are secured against corruption by
1989CRC32 checksums.
wdenkc6097192002-11-03 00:24:07 +00001990
wdenkc6097192002-11-03 00:24:07 +00001991
wdenk6c59edc2004-05-03 20:45:30 +00001992Linux Support:
1993==============
wdenkc6097192002-11-03 00:24:07 +00001994
wdenk6c59edc2004-05-03 20:45:30 +00001995Although U-Boot should support any OS or standalone application
1996easily, the main focus has always been on Linux during the design of
1997U-Boot.
wdenkc6097192002-11-03 00:24:07 +00001998
wdenk6c59edc2004-05-03 20:45:30 +00001999U-Boot includes many features that so far have been part of some
2000special "boot loader" code within the Linux kernel. Also, any
2001"initrd" images to be used are no longer part of one big Linux image;
2002instead, kernel and "initrd" are separate images. This implementation
2003serves several purposes:
wdenkc6097192002-11-03 00:24:07 +00002004
wdenk6c59edc2004-05-03 20:45:30 +00002005- the same features can be used for other OS or standalone
2006 applications (for instance: using compressed images to reduce the
2007 Flash memory footprint)
wdenkc6097192002-11-03 00:24:07 +00002008
wdenk6c59edc2004-05-03 20:45:30 +00002009- it becomes much easier to port new Linux kernel versions because
2010 lots of low-level, hardware dependent stuff are done by U-Boot
wdenkc6097192002-11-03 00:24:07 +00002011
wdenk6c59edc2004-05-03 20:45:30 +00002012- the same Linux kernel image can now be used with different "initrd"
2013 images; of course this also means that different kernel images can
2014 be run with the same "initrd". This makes testing easier (you don't
2015 have to build a new "zImage.initrd" Linux image when you just
2016 change a file in your "initrd"). Also, a field-upgrade of the
2017 software is easier now.
wdenkc6097192002-11-03 00:24:07 +00002018
wdenkc6097192002-11-03 00:24:07 +00002019
wdenk6c59edc2004-05-03 20:45:30 +00002020Linux HOWTO:
2021============
wdenkc6097192002-11-03 00:24:07 +00002022
wdenk6c59edc2004-05-03 20:45:30 +00002023Porting Linux to U-Boot based systems:
2024---------------------------------------
wdenkc6097192002-11-03 00:24:07 +00002025
wdenk6c59edc2004-05-03 20:45:30 +00002026U-Boot cannot save you from doing all the necessary modifications to
2027configure the Linux device drivers for use with your target hardware
2028(no, we don't intend to provide a full virtual machine interface to
2029Linux :-).
wdenkc6097192002-11-03 00:24:07 +00002030
Stefan Roese88fbf932010-04-15 16:07:28 +02002031But now you can ignore ALL boot loader code (in arch/powerpc/mbxboot).
wdenkc6097192002-11-03 00:24:07 +00002032
wdenk6c59edc2004-05-03 20:45:30 +00002033Just make sure your machine specific header file (for instance
2034include/asm-ppc/tqm8xx.h) includes the same definition of the Board
Markus Heidelberg47167572008-09-07 20:18:27 +02002035Information structure as we define in include/asm-<arch>/u-boot.h,
2036and make sure that your definition of IMAP_ADDR uses the same value
Jean-Christophe PLAGNIOL-VILLARD03836942008-10-16 15:01:15 +02002037as your U-Boot configuration in CONFIG_SYS_IMMR.
wdenkc6097192002-11-03 00:24:07 +00002038
Simon Glassd097e592014-06-11 23:29:46 -06002039Note that U-Boot now has a driver model, a unified model for drivers.
2040If you are adding a new driver, plumb it into driver model. If there
2041is no uclass available, you are encouraged to create one. See
2042doc/driver-model.
2043
wdenkc6097192002-11-03 00:24:07 +00002044
wdenk6c59edc2004-05-03 20:45:30 +00002045Configuring the Linux kernel:
2046-----------------------------
wdenkc6097192002-11-03 00:24:07 +00002047
wdenk6c59edc2004-05-03 20:45:30 +00002048No specific requirements for U-Boot. Make sure you have some root
2049device (initial ramdisk, NFS) for your target system.
wdenkc6097192002-11-03 00:24:07 +00002050
wdenkc6097192002-11-03 00:24:07 +00002051
wdenk6c59edc2004-05-03 20:45:30 +00002052Building a Linux Image:
2053-----------------------
wdenkc6097192002-11-03 00:24:07 +00002054
wdenk6c59edc2004-05-03 20:45:30 +00002055With U-Boot, "normal" build targets like "zImage" or "bzImage" are
2056not used. If you use recent kernel source, a new build target
2057"uImage" will exist which automatically builds an image usable by
2058U-Boot. Most older kernels also have support for a "pImage" target,
2059which was introduced for our predecessor project PPCBoot and uses a
2060100% compatible format.
wdenkc6097192002-11-03 00:24:07 +00002061
wdenk6c59edc2004-05-03 20:45:30 +00002062Example:
wdenkc6097192002-11-03 00:24:07 +00002063
Holger Freyther7ba4e572014-08-04 09:26:05 +02002064 make TQM850L_defconfig
wdenk6c59edc2004-05-03 20:45:30 +00002065 make oldconfig
2066 make dep
2067 make uImage
wdenkc6097192002-11-03 00:24:07 +00002068
wdenk6c59edc2004-05-03 20:45:30 +00002069The "uImage" build target uses a special tool (in 'tools/mkimage') to
2070encapsulate a compressed Linux kernel image with header information,
2071CRC32 checksum etc. for use with U-Boot. This is what we are doing:
wdenkc6097192002-11-03 00:24:07 +00002072
wdenk6c59edc2004-05-03 20:45:30 +00002073* build a standard "vmlinux" kernel image (in ELF binary format):
wdenkc6097192002-11-03 00:24:07 +00002074
wdenk6c59edc2004-05-03 20:45:30 +00002075* convert the kernel into a raw binary image:
wdenkc6097192002-11-03 00:24:07 +00002076
wdenk6c59edc2004-05-03 20:45:30 +00002077 ${CROSS_COMPILE}-objcopy -O binary \
2078 -R .note -R .comment \
2079 -S vmlinux linux.bin
wdenk24ee89b2002-11-03 17:56:27 +00002080
wdenk6c59edc2004-05-03 20:45:30 +00002081* compress the binary image:
wdenk24ee89b2002-11-03 17:56:27 +00002082
wdenk6c59edc2004-05-03 20:45:30 +00002083 gzip -9 linux.bin
wdenk24ee89b2002-11-03 17:56:27 +00002084
wdenk6c59edc2004-05-03 20:45:30 +00002085* package compressed binary image for U-Boot:
wdenk24ee89b2002-11-03 17:56:27 +00002086
wdenk6c59edc2004-05-03 20:45:30 +00002087 mkimage -A ppc -O linux -T kernel -C gzip \
2088 -a 0 -e 0 -n "Linux Kernel Image" \
2089 -d linux.bin.gz uImage
wdenkc6097192002-11-03 00:24:07 +00002090
wdenkc6097192002-11-03 00:24:07 +00002091
wdenk6c59edc2004-05-03 20:45:30 +00002092The "mkimage" tool can also be used to create ramdisk images for use
2093with U-Boot, either separated from the Linux kernel image, or
2094combined into one file. "mkimage" encapsulates the images with a 64
2095byte header containing information about target architecture,
2096operating system, image type, compression method, entry points, time
2097stamp, CRC32 checksums, etc.
wdenkc6097192002-11-03 00:24:07 +00002098
wdenk6c59edc2004-05-03 20:45:30 +00002099"mkimage" can be called in two ways: to verify existing images and
2100print the header information, or to build new images.
wdenk24ee89b2002-11-03 17:56:27 +00002101
wdenk6c59edc2004-05-03 20:45:30 +00002102In the first form (with "-l" option) mkimage lists the information
2103contained in the header of an existing U-Boot image; this includes
2104checksum verification:
wdenk24ee89b2002-11-03 17:56:27 +00002105
wdenk6c59edc2004-05-03 20:45:30 +00002106 tools/mkimage -l image
2107 -l ==> list image header information
wdenk24ee89b2002-11-03 17:56:27 +00002108
wdenk6c59edc2004-05-03 20:45:30 +00002109The second form (with "-d" option) is used to build a U-Boot image
2110from a "data file" which is used as image payload:
wdenk24ee89b2002-11-03 17:56:27 +00002111
wdenk6c59edc2004-05-03 20:45:30 +00002112 tools/mkimage -A arch -O os -T type -C comp -a addr -e ep \
2113 -n name -d data_file image
2114 -A ==> set architecture to 'arch'
2115 -O ==> set operating system to 'os'
2116 -T ==> set image type to 'type'
2117 -C ==> set compression type 'comp'
2118 -a ==> set load address to 'addr' (hex)
2119 -e ==> set entry point to 'ep' (hex)
2120 -n ==> set image name to 'name'
2121 -d ==> use image data from 'datafile'
wdenk24ee89b2002-11-03 17:56:27 +00002122
wdenkcd914452004-05-29 16:53:29 +00002123Right now, all Linux kernels for PowerPC systems use the same load
2124address (0x00000000), but the entry point address depends on the
2125kernel version:
wdenkc6097192002-11-03 00:24:07 +00002126
wdenk6c59edc2004-05-03 20:45:30 +00002127- 2.2.x kernels have the entry point at 0x0000000C,
2128- 2.3.x and later kernels have the entry point at 0x00000000.
wdenkc6097192002-11-03 00:24:07 +00002129
wdenk6c59edc2004-05-03 20:45:30 +00002130So a typical call to build a U-Boot image would read:
wdenkc6097192002-11-03 00:24:07 +00002131
wdenk6c59edc2004-05-03 20:45:30 +00002132 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \
2133 > -A ppc -O linux -T kernel -C gzip -a 0 -e 0 \
Stefan Roese88fbf932010-04-15 16:07:28 +02002134 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux.gz \
wdenk6c59edc2004-05-03 20:45:30 +00002135 > examples/uImage.TQM850L
2136 Image Name: 2.4.4 kernel for TQM850L
2137 Created: Wed Jul 19 02:34:59 2000
2138 Image Type: PowerPC Linux Kernel Image (gzip compressed)
2139 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB
2140 Load Address: 0x00000000
2141 Entry Point: 0x00000000
wdenkc6097192002-11-03 00:24:07 +00002142
wdenk6c59edc2004-05-03 20:45:30 +00002143To verify the contents of the image (or check for corruption):
wdenkc6097192002-11-03 00:24:07 +00002144
wdenk6c59edc2004-05-03 20:45:30 +00002145 -> tools/mkimage -l examples/uImage.TQM850L
2146 Image Name: 2.4.4 kernel for TQM850L
2147 Created: Wed Jul 19 02:34:59 2000
2148 Image Type: PowerPC Linux Kernel Image (gzip compressed)
2149 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB
2150 Load Address: 0x00000000
2151 Entry Point: 0x00000000
wdenkc6097192002-11-03 00:24:07 +00002152
wdenk6c59edc2004-05-03 20:45:30 +00002153NOTE: for embedded systems where boot time is critical you can trade
2154speed for memory and install an UNCOMPRESSED image instead: this
2155needs more space in Flash, but boots much faster since it does not
2156need to be uncompressed:
wdenkc6097192002-11-03 00:24:07 +00002157
Stefan Roese88fbf932010-04-15 16:07:28 +02002158 -> gunzip /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux.gz
wdenk6c59edc2004-05-03 20:45:30 +00002159 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \
2160 > -A ppc -O linux -T kernel -C none -a 0 -e 0 \
Stefan Roese88fbf932010-04-15 16:07:28 +02002161 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux \
wdenk6c59edc2004-05-03 20:45:30 +00002162 > examples/uImage.TQM850L-uncompressed
2163 Image Name: 2.4.4 kernel for TQM850L
2164 Created: Wed Jul 19 02:34:59 2000
2165 Image Type: PowerPC Linux Kernel Image (uncompressed)
2166 Data Size: 792160 Bytes = 773.59 kB = 0.76 MB
2167 Load Address: 0x00000000
2168 Entry Point: 0x00000000
wdenkc6097192002-11-03 00:24:07 +00002169
wdenkc6097192002-11-03 00:24:07 +00002170
wdenk6c59edc2004-05-03 20:45:30 +00002171Similar you can build U-Boot images from a 'ramdisk.image.gz' file
2172when your kernel is intended to use an initial ramdisk:
wdenkc6097192002-11-03 00:24:07 +00002173
wdenk6c59edc2004-05-03 20:45:30 +00002174 -> tools/mkimage -n 'Simple Ramdisk Image' \
2175 > -A ppc -O linux -T ramdisk -C gzip \
2176 > -d /LinuxPPC/images/SIMPLE-ramdisk.image.gz examples/simple-initrd
2177 Image Name: Simple Ramdisk Image
2178 Created: Wed Jan 12 14:01:50 2000
2179 Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
2180 Data Size: 566530 Bytes = 553.25 kB = 0.54 MB
2181 Load Address: 0x00000000
2182 Entry Point: 0x00000000
wdenkc6097192002-11-03 00:24:07 +00002183
Tyler Hicks791c7472020-10-26 10:40:24 -05002184The "dumpimage" tool can be used to disassemble or list the contents of images
2185built by mkimage. See dumpimage's help output (-h) for details.
wdenkc6097192002-11-03 00:24:07 +00002186
wdenk6c59edc2004-05-03 20:45:30 +00002187Installing a Linux Image:
2188-------------------------
wdenkc6097192002-11-03 00:24:07 +00002189
wdenk6c59edc2004-05-03 20:45:30 +00002190To downloading a U-Boot image over the serial (console) interface,
2191you must convert the image to S-Record format:
wdenkc6097192002-11-03 00:24:07 +00002192
wdenk6c59edc2004-05-03 20:45:30 +00002193 objcopy -I binary -O srec examples/image examples/image.srec
wdenkc6097192002-11-03 00:24:07 +00002194
wdenk6c59edc2004-05-03 20:45:30 +00002195The 'objcopy' does not understand the information in the U-Boot
2196image header, so the resulting S-Record file will be relative to
2197address 0x00000000. To load it to a given address, you need to
2198specify the target address as 'offset' parameter with the 'loads'
2199command.
wdenkc6097192002-11-03 00:24:07 +00002200
wdenk6c59edc2004-05-03 20:45:30 +00002201Example: install the image to address 0x40100000 (which on the
2202TQM8xxL is in the first Flash bank):
wdenkc6097192002-11-03 00:24:07 +00002203
wdenk6c59edc2004-05-03 20:45:30 +00002204 => erase 40100000 401FFFFF
wdenkc6097192002-11-03 00:24:07 +00002205
wdenk6c59edc2004-05-03 20:45:30 +00002206 .......... done
2207 Erased 8 sectors
wdenkc6097192002-11-03 00:24:07 +00002208
wdenk6c59edc2004-05-03 20:45:30 +00002209 => loads 40100000
2210 ## Ready for S-Record download ...
2211 ~>examples/image.srec
2212 1 2 3 4 5 6 7 8 9 10 11 12 13 ...
2213 ...
2214 15989 15990 15991 15992
2215 [file transfer complete]
2216 [connected]
2217 ## Start Addr = 0x00000000
wdenkc6097192002-11-03 00:24:07 +00002218
wdenkc6097192002-11-03 00:24:07 +00002219
wdenk6c59edc2004-05-03 20:45:30 +00002220You can check the success of the download using the 'iminfo' command;
Wolfgang Denkb240aef2008-03-26 10:40:12 +01002221this includes a checksum verification so you can be sure no data
wdenk6c59edc2004-05-03 20:45:30 +00002222corruption happened:
wdenkc6097192002-11-03 00:24:07 +00002223
wdenk6c59edc2004-05-03 20:45:30 +00002224 => imi 40100000
wdenkc6097192002-11-03 00:24:07 +00002225
wdenk6c59edc2004-05-03 20:45:30 +00002226 ## Checking Image at 40100000 ...
2227 Image Name: 2.2.13 for initrd on TQM850L
2228 Image Type: PowerPC Linux Kernel Image (gzip compressed)
2229 Data Size: 335725 Bytes = 327 kB = 0 MB
2230 Load Address: 00000000
2231 Entry Point: 0000000c
2232 Verifying Checksum ... OK
wdenkc6097192002-11-03 00:24:07 +00002233
2234
wdenk6c59edc2004-05-03 20:45:30 +00002235Boot Linux:
2236-----------
wdenkc6097192002-11-03 00:24:07 +00002237
wdenk6c59edc2004-05-03 20:45:30 +00002238The "bootm" command is used to boot an application that is stored in
2239memory (RAM or Flash). In case of a Linux kernel image, the contents
2240of the "bootargs" environment variable is passed to the kernel as
2241parameters. You can check and modify this variable using the
2242"printenv" and "setenv" commands:
wdenkc6097192002-11-03 00:24:07 +00002243
wdenkc6097192002-11-03 00:24:07 +00002244
wdenk6c59edc2004-05-03 20:45:30 +00002245 => printenv bootargs
2246 bootargs=root=/dev/ram
wdenkc6097192002-11-03 00:24:07 +00002247
wdenk6c59edc2004-05-03 20:45:30 +00002248 => 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 +00002249
wdenk6c59edc2004-05-03 20:45:30 +00002250 => printenv bootargs
2251 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 +00002252
wdenk6c59edc2004-05-03 20:45:30 +00002253 => bootm 40020000
2254 ## Booting Linux kernel at 40020000 ...
2255 Image Name: 2.2.13 for NFS on TQM850L
2256 Image Type: PowerPC Linux Kernel Image (gzip compressed)
2257 Data Size: 381681 Bytes = 372 kB = 0 MB
2258 Load Address: 00000000
2259 Entry Point: 0000000c
2260 Verifying Checksum ... OK
2261 Uncompressing Kernel Image ... OK
2262 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
2263 Boot arguments: root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
2264 time_init: decrementer frequency = 187500000/60
2265 Calibrating delay loop... 49.77 BogoMIPS
2266 Memory: 15208k available (700k kernel code, 444k data, 32k init) [c0000000,c1000000]
2267 ...
wdenkc6097192002-11-03 00:24:07 +00002268
Marcel Ziswilerabd8dcb2008-07-09 08:17:15 +02002269If you want to boot a Linux kernel with initial RAM disk, you pass
wdenk6c59edc2004-05-03 20:45:30 +00002270the memory addresses of both the kernel and the initrd image (PPBCOOT
2271format!) to the "bootm" command:
wdenkc6097192002-11-03 00:24:07 +00002272
wdenk6c59edc2004-05-03 20:45:30 +00002273 => imi 40100000 40200000
wdenkc6097192002-11-03 00:24:07 +00002274
wdenk6c59edc2004-05-03 20:45:30 +00002275 ## Checking Image at 40100000 ...
2276 Image Name: 2.2.13 for initrd on TQM850L
2277 Image Type: PowerPC Linux Kernel Image (gzip compressed)
2278 Data Size: 335725 Bytes = 327 kB = 0 MB
2279 Load Address: 00000000
2280 Entry Point: 0000000c
2281 Verifying Checksum ... OK
wdenkc6097192002-11-03 00:24:07 +00002282
wdenk6c59edc2004-05-03 20:45:30 +00002283 ## Checking Image at 40200000 ...
2284 Image Name: Simple Ramdisk Image
2285 Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
2286 Data Size: 566530 Bytes = 553 kB = 0 MB
2287 Load Address: 00000000
2288 Entry Point: 00000000
2289 Verifying Checksum ... OK
wdenkc6097192002-11-03 00:24:07 +00002290
wdenk6c59edc2004-05-03 20:45:30 +00002291 => bootm 40100000 40200000
2292 ## Booting Linux kernel at 40100000 ...
2293 Image Name: 2.2.13 for initrd on TQM850L
2294 Image Type: PowerPC Linux Kernel Image (gzip compressed)
2295 Data Size: 335725 Bytes = 327 kB = 0 MB
2296 Load Address: 00000000
2297 Entry Point: 0000000c
2298 Verifying Checksum ... OK
2299 Uncompressing Kernel Image ... OK
2300 ## Loading RAMDisk Image at 40200000 ...
2301 Image Name: Simple Ramdisk Image
2302 Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
2303 Data Size: 566530 Bytes = 553 kB = 0 MB
2304 Load Address: 00000000
2305 Entry Point: 00000000
2306 Verifying Checksum ... OK
2307 Loading Ramdisk ... OK
2308 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
2309 Boot arguments: root=/dev/ram
2310 time_init: decrementer frequency = 187500000/60
2311 Calibrating delay loop... 49.77 BogoMIPS
2312 ...
2313 RAMDISK: Compressed image found at block 0
2314 VFS: Mounted root (ext2 filesystem).
wdenkc6097192002-11-03 00:24:07 +00002315
wdenk6c59edc2004-05-03 20:45:30 +00002316 bash#
wdenkc6097192002-11-03 00:24:07 +00002317
Matthew McClintockefae4ca2006-06-28 10:41:37 -05002318Boot Linux and pass a flat device tree:
2319-----------
2320
2321First, U-Boot must be compiled with the appropriate defines. See the section
2322titled "Linux Kernel Interface" above for a more in depth explanation. The
2323following is an example of how to start a kernel and pass an updated
2324flat device tree:
2325
2326=> print oftaddr
2327oftaddr=0x300000
2328=> print oft
2329oft=oftrees/mpc8540ads.dtb
2330=> tftp $oftaddr $oft
2331Speed: 1000, full duplex
2332Using TSEC0 device
2333TFTP from server 192.168.1.1; our IP address is 192.168.1.101
2334Filename 'oftrees/mpc8540ads.dtb'.
2335Load address: 0x300000
2336Loading: #
2337done
2338Bytes transferred = 4106 (100a hex)
2339=> tftp $loadaddr $bootfile
2340Speed: 1000, full duplex
2341Using TSEC0 device
2342TFTP from server 192.168.1.1; our IP address is 192.168.1.2
2343Filename 'uImage'.
2344Load address: 0x200000
2345Loading:############
2346done
2347Bytes transferred = 1029407 (fb51f hex)
2348=> print loadaddr
2349loadaddr=200000
2350=> print oftaddr
2351oftaddr=0x300000
2352=> bootm $loadaddr - $oftaddr
2353## Booting image at 00200000 ...
Wolfgang Denk018147d2006-11-27 15:32:42 +01002354 Image Name: Linux-2.6.17-dirty
2355 Image Type: PowerPC Linux Kernel Image (gzip compressed)
2356 Data Size: 1029343 Bytes = 1005.2 kB
Matthew McClintockefae4ca2006-06-28 10:41:37 -05002357 Load Address: 00000000
Wolfgang Denk018147d2006-11-27 15:32:42 +01002358 Entry Point: 00000000
Matthew McClintockefae4ca2006-06-28 10:41:37 -05002359 Verifying Checksum ... OK
2360 Uncompressing Kernel Image ... OK
2361Booting using flat device tree at 0x300000
2362Using MPC85xx ADS machine description
2363Memory CAM mapping: CAM0=256Mb, CAM1=256Mb, CAM2=0Mb residual: 0Mb
2364[snip]
2365
2366
wdenk6c59edc2004-05-03 20:45:30 +00002367More About U-Boot Image Types:
2368------------------------------
wdenkc6097192002-11-03 00:24:07 +00002369
wdenk6c59edc2004-05-03 20:45:30 +00002370U-Boot supports the following image types:
wdenkc6097192002-11-03 00:24:07 +00002371
wdenk6c59edc2004-05-03 20:45:30 +00002372 "Standalone Programs" are directly runnable in the environment
2373 provided by U-Boot; it is expected that (if they behave
2374 well) you can continue to work in U-Boot after return from
2375 the Standalone Program.
2376 "OS Kernel Images" are usually images of some Embedded OS which
2377 will take over control completely. Usually these programs
2378 will install their own set of exception handlers, device
2379 drivers, set up the MMU, etc. - this means, that you cannot
2380 expect to re-enter U-Boot except by resetting the CPU.
2381 "RAMDisk Images" are more or less just data blocks, and their
2382 parameters (address, size) are passed to an OS kernel that is
2383 being started.
2384 "Multi-File Images" contain several images, typically an OS
2385 (Linux) kernel image and one or more data images like
2386 RAMDisks. This construct is useful for instance when you want
2387 to boot over the network using BOOTP etc., where the boot
2388 server provides just a single image file, but you want to get
2389 for instance an OS kernel and a RAMDisk image.
wdenkc6097192002-11-03 00:24:07 +00002390
wdenk6c59edc2004-05-03 20:45:30 +00002391 "Multi-File Images" start with a list of image sizes, each
2392 image size (in bytes) specified by an "uint32_t" in network
2393 byte order. This list is terminated by an "(uint32_t)0".
2394 Immediately after the terminating 0 follow the images, one by
2395 one, all aligned on "uint32_t" boundaries (size rounded up to
2396 a multiple of 4 bytes).
wdenkc6097192002-11-03 00:24:07 +00002397
wdenk6c59edc2004-05-03 20:45:30 +00002398 "Firmware Images" are binary images containing firmware (like
2399 U-Boot or FPGA images) which usually will be programmed to
2400 flash memory.
wdenk4fc95692003-02-28 00:49:47 +00002401
wdenk6c59edc2004-05-03 20:45:30 +00002402 "Script files" are command sequences that will be executed by
2403 U-Boot's command interpreter; this feature is especially
2404 useful when you configure U-Boot to use a real shell (hush)
2405 as command interpreter.
wdenk4fc95692003-02-28 00:49:47 +00002406
Marek Vasutcf41a9b2012-03-14 21:52:45 +00002407Booting the Linux zImage:
2408-------------------------
2409
2410On some platforms, it's possible to boot Linux zImage. This is done
2411using the "bootz" command. The syntax of "bootz" command is the same
2412as the syntax of "bootm" command.
2413
Tom Rini45f46d12013-05-16 11:40:11 -04002414Note, defining the CONFIG_SUPPORT_RAW_INITRD allows user to supply
Marek Vasut28850d02012-03-18 11:47:58 +00002415kernel with raw initrd images. The syntax is slightly different, the
2416address of the initrd must be augmented by it's size, in the following
2417format: "<initrd addres>:<initrd size>".
2418
stroeseb9c17c52003-04-04 15:53:41 +00002419
wdenk6c59edc2004-05-03 20:45:30 +00002420Standalone HOWTO:
2421=================
stroeseb9c17c52003-04-04 15:53:41 +00002422
wdenk6c59edc2004-05-03 20:45:30 +00002423One of the features of U-Boot is that you can dynamically load and
2424run "standalone" applications, which can use some resources of
2425U-Boot like console I/O functions or interrupt services.
stroeseb9c17c52003-04-04 15:53:41 +00002426
wdenk6c59edc2004-05-03 20:45:30 +00002427Two simple examples are included with the sources:
wdenk4fc95692003-02-28 00:49:47 +00002428
wdenk6c59edc2004-05-03 20:45:30 +00002429"Hello World" Demo:
2430-------------------
wdenkc6097192002-11-03 00:24:07 +00002431
wdenk6c59edc2004-05-03 20:45:30 +00002432'examples/hello_world.c' contains a small "Hello World" Demo
2433application; it is automatically compiled when you build U-Boot.
2434It's configured to run at address 0x00040004, so you can play with it
2435like that:
wdenkc6097192002-11-03 00:24:07 +00002436
wdenk6c59edc2004-05-03 20:45:30 +00002437 => loads
2438 ## Ready for S-Record download ...
2439 ~>examples/hello_world.srec
2440 1 2 3 4 5 6 7 8 9 10 11 ...
2441 [file transfer complete]
2442 [connected]
2443 ## Start Addr = 0x00040004
wdenkc6097192002-11-03 00:24:07 +00002444
wdenk6c59edc2004-05-03 20:45:30 +00002445 => go 40004 Hello World! This is a test.
2446 ## Starting application at 0x00040004 ...
2447 Hello World
2448 argc = 7
2449 argv[0] = "40004"
2450 argv[1] = "Hello"
2451 argv[2] = "World!"
2452 argv[3] = "This"
2453 argv[4] = "is"
2454 argv[5] = "a"
2455 argv[6] = "test."
2456 argv[7] = "<NULL>"
2457 Hit any key to exit ...
wdenkc6097192002-11-03 00:24:07 +00002458
wdenk6c59edc2004-05-03 20:45:30 +00002459 ## Application terminated, rc = 0x0
wdenkc6097192002-11-03 00:24:07 +00002460
wdenk6c59edc2004-05-03 20:45:30 +00002461Another example, which demonstrates how to register a CPM interrupt
2462handler with the U-Boot code, can be found in 'examples/timer.c'.
2463Here, a CPM timer is set up to generate an interrupt every second.
2464The interrupt service routine is trivial, just printing a '.'
2465character, but this is just a demo program. The application can be
2466controlled by the following keys:
wdenkc6097192002-11-03 00:24:07 +00002467
wdenk6c59edc2004-05-03 20:45:30 +00002468 ? - print current values og the CPM Timer registers
2469 b - enable interrupts and start timer
2470 e - stop timer and disable interrupts
2471 q - quit application
wdenkc6097192002-11-03 00:24:07 +00002472
wdenk6c59edc2004-05-03 20:45:30 +00002473 => loads
2474 ## Ready for S-Record download ...
2475 ~>examples/timer.srec
2476 1 2 3 4 5 6 7 8 9 10 11 ...
2477 [file transfer complete]
2478 [connected]
2479 ## Start Addr = 0x00040004
wdenkc6097192002-11-03 00:24:07 +00002480
wdenk6c59edc2004-05-03 20:45:30 +00002481 => go 40004
2482 ## Starting application at 0x00040004 ...
2483 TIMERS=0xfff00980
2484 Using timer 1
2485 tgcr @ 0xfff00980, tmr @ 0xfff00990, trr @ 0xfff00994, tcr @ 0xfff00998, tcn @ 0xfff0099c, ter @ 0xfff009b0
wdenkc6097192002-11-03 00:24:07 +00002486
wdenk6c59edc2004-05-03 20:45:30 +00002487Hit 'b':
2488 [q, b, e, ?] Set interval 1000000 us
2489 Enabling timer
2490Hit '?':
2491 [q, b, e, ?] ........
2492 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0xef6, ter=0x0
2493Hit '?':
2494 [q, b, e, ?] .
2495 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x2ad4, ter=0x0
2496Hit '?':
2497 [q, b, e, ?] .
2498 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x1efc, ter=0x0
2499Hit '?':
2500 [q, b, e, ?] .
2501 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x169d, ter=0x0
2502Hit 'e':
2503 [q, b, e, ?] ...Stopping timer
2504Hit 'q':
2505 [q, b, e, ?] ## Application terminated, rc = 0x0
wdenkc6097192002-11-03 00:24:07 +00002506
wdenkc6097192002-11-03 00:24:07 +00002507
wdenk6c59edc2004-05-03 20:45:30 +00002508Minicom warning:
2509================
wdenkc6097192002-11-03 00:24:07 +00002510
wdenk6c59edc2004-05-03 20:45:30 +00002511Over time, many people have reported problems when trying to use the
2512"minicom" terminal emulation program for serial download. I (wd)
2513consider minicom to be broken, and recommend not to use it. Under
2514Unix, I recommend to use C-Kermit for general purpose use (and
2515especially for kermit binary protocol download ("loadb" command), and
Karl O. Pinca0189bb2012-10-01 05:11:56 +00002516use "cu" for S-Record download ("loads" command). See
Naoki Hayamae0cc1852020-10-08 13:17:16 +09002517https://www.denx.de/wiki/view/DULG/SystemSetup#Section_4.3.
Karl O. Pinca0189bb2012-10-01 05:11:56 +00002518for help with kermit.
2519
wdenkc6097192002-11-03 00:24:07 +00002520
wdenk6c59edc2004-05-03 20:45:30 +00002521Nevertheless, if you absolutely want to use it try adding this
2522configuration to your "File transfer protocols" section:
wdenkc6097192002-11-03 00:24:07 +00002523
wdenk6c59edc2004-05-03 20:45:30 +00002524 Name Program Name U/D FullScr IO-Red. Multi
2525 X kermit /usr/bin/kermit -i -l %l -s Y U Y N N
2526 Y kermit /usr/bin/kermit -i -l %l -r N D Y N N
wdenk8dba0502003-03-31 16:34:49 +00002527
wdenk8dba0502003-03-31 16:34:49 +00002528
wdenk6c59edc2004-05-03 20:45:30 +00002529NetBSD Notes:
2530=============
wdenkc6097192002-11-03 00:24:07 +00002531
wdenk6c59edc2004-05-03 20:45:30 +00002532Starting at version 0.9.2, U-Boot supports NetBSD both as host
2533(build U-Boot) and target system (boots NetBSD/mpc8xx).
wdenk88e72a32003-06-19 23:04:19 +00002534
wdenk6c59edc2004-05-03 20:45:30 +00002535Building requires a cross environment; it is known to work on
2536NetBSD/i386 with the cross-powerpc-netbsd-1.3 package (you will also
2537need gmake since the Makefiles are not compatible with BSD make).
2538Note that the cross-powerpc package does not install include files;
2539attempting to build U-Boot will fail because <machine/ansi.h> is
2540missing. This file has to be installed and patched manually:
wdenk88e72a32003-06-19 23:04:19 +00002541
wdenk6c59edc2004-05-03 20:45:30 +00002542 # cd /usr/pkg/cross/powerpc-netbsd/include
2543 # mkdir powerpc
2544 # ln -s powerpc machine
2545 # cp /usr/src/sys/arch/powerpc/include/ansi.h powerpc/ansi.h
2546 # ${EDIT} powerpc/ansi.h ## must remove __va_list, _BSD_VA_LIST
wdenk88e72a32003-06-19 23:04:19 +00002547
wdenk6c59edc2004-05-03 20:45:30 +00002548Native builds *don't* work due to incompatibilities between native
2549and U-Boot include files.
wdenkc6097192002-11-03 00:24:07 +00002550
wdenk6c59edc2004-05-03 20:45:30 +00002551Booting assumes that (the first part of) the image booted is a
2552stage-2 loader which in turn loads and then invokes the kernel
2553proper. Loader sources will eventually appear in the NetBSD source
2554tree (probably in sys/arc/mpc8xx/stand/u-boot_stage2/); in the
wdenkd0245fc2005-04-13 10:02:42 +00002555meantime, see ftp://ftp.denx.de/pub/u-boot/ppcboot_stage2.tar.gz
wdenkc6097192002-11-03 00:24:07 +00002556
wdenkc6097192002-11-03 00:24:07 +00002557
wdenk6c59edc2004-05-03 20:45:30 +00002558Implementation Internals:
2559=========================
wdenkc6097192002-11-03 00:24:07 +00002560
wdenk6c59edc2004-05-03 20:45:30 +00002561The following is not intended to be a complete description of every
2562implementation detail. However, it should help to understand the
2563inner workings of U-Boot and make it easier to port it to custom
2564hardware.
wdenkc6097192002-11-03 00:24:07 +00002565
wdenkc6097192002-11-03 00:24:07 +00002566
wdenk6c59edc2004-05-03 20:45:30 +00002567Initial Stack, Global Data:
2568---------------------------
wdenkc6097192002-11-03 00:24:07 +00002569
wdenk6c59edc2004-05-03 20:45:30 +00002570The implementation of U-Boot is complicated by the fact that U-Boot
2571starts running out of ROM (flash memory), usually without access to
2572system RAM (because the memory controller is not initialized yet).
2573This means that we don't have writable Data or BSS segments, and BSS
2574is not initialized as zero. To be able to get a C environment working
2575at all, we have to allocate at least a minimal stack. Implementation
2576options for this are defined and restricted by the CPU used: Some CPU
2577models provide on-chip memory (like the IMMR area on MPC8xx and
2578MPC826x processors), on others (parts of) the data cache can be
2579locked as (mis-) used as memory, etc.
wdenkc6097192002-11-03 00:24:07 +00002580
Wolfgang Denkb240aef2008-03-26 10:40:12 +01002581 Chris Hallinan posted a good summary of these issues to the
Wolfgang Denk290ae6b2008-12-30 22:56:11 +01002582 U-Boot mailing list:
wdenkc6097192002-11-03 00:24:07 +00002583
wdenk6c59edc2004-05-03 20:45:30 +00002584 Subject: RE: [U-Boot-Users] RE: More On Memory Bank x (nothingness)?
2585 From: "Chris Hallinan" <clh@net1plus.com>
2586 Date: Mon, 10 Feb 2003 16:43:46 -0500 (22:43 MET)
2587 ...
wdenkc6097192002-11-03 00:24:07 +00002588
wdenk6c59edc2004-05-03 20:45:30 +00002589 Correct me if I'm wrong, folks, but the way I understand it
2590 is this: Using DCACHE as initial RAM for Stack, etc, does not
2591 require any physical RAM backing up the cache. The cleverness
2592 is that the cache is being used as a temporary supply of
2593 necessary storage before the SDRAM controller is setup. It's
Marcel Ziswilerabd8dcb2008-07-09 08:17:15 +02002594 beyond the scope of this list to explain the details, but you
wdenk6c59edc2004-05-03 20:45:30 +00002595 can see how this works by studying the cache architecture and
2596 operation in the architecture and processor-specific manuals.
wdenkc6097192002-11-03 00:24:07 +00002597
wdenk6c59edc2004-05-03 20:45:30 +00002598 OCM is On Chip Memory, which I believe the 405GP has 4K. It
2599 is another option for the system designer to use as an
Marcel Ziswilerabd8dcb2008-07-09 08:17:15 +02002600 initial stack/RAM area prior to SDRAM being available. Either
wdenk6c59edc2004-05-03 20:45:30 +00002601 option should work for you. Using CS 4 should be fine if your
2602 board designers haven't used it for something that would
2603 cause you grief during the initial boot! It is frequently not
2604 used.
wdenkc6097192002-11-03 00:24:07 +00002605
Tom Rini6a5dccc2022-11-16 13:10:41 -05002606 CFG_SYS_INIT_RAM_ADDR should be somewhere that won't interfere
wdenk6c59edc2004-05-03 20:45:30 +00002607 with your processor/board/system design. The default value
2608 you will find in any recent u-boot distribution in
Stefan Roese3e1f1b32005-08-01 16:49:12 +02002609 walnut.h should work for you. I'd set it to a value larger
wdenk6c59edc2004-05-03 20:45:30 +00002610 than your SDRAM module. If you have a 64MB SDRAM module, set
2611 it above 400_0000. Just make sure your board has no resources
2612 that are supposed to respond to that address! That code in
2613 start.S has been around a while and should work as is when
2614 you get the config right.
wdenk4a5c8a72003-03-06 00:02:04 +00002615
wdenk6c59edc2004-05-03 20:45:30 +00002616 -Chris Hallinan
2617 DS4.COM, Inc.
wdenk4a5c8a72003-03-06 00:02:04 +00002618
wdenk6c59edc2004-05-03 20:45:30 +00002619It is essential to remember this, since it has some impact on the C
2620code for the initialization procedures:
wdenk4a5c8a72003-03-06 00:02:04 +00002621
wdenk6c59edc2004-05-03 20:45:30 +00002622* Initialized global data (data segment) is read-only. Do not attempt
2623 to write it.
wdenk4a5c8a72003-03-06 00:02:04 +00002624
Jeremiah Mahler03f930c2015-01-04 18:56:50 -08002625* Do not use any uninitialized global data (or implicitly initialized
wdenk6c59edc2004-05-03 20:45:30 +00002626 as zero data - BSS segment) at all - this is undefined, initiali-
2627 zation is performed later (when relocating to RAM).
wdenk4a5c8a72003-03-06 00:02:04 +00002628
wdenk6c59edc2004-05-03 20:45:30 +00002629* Stack space is very limited. Avoid big data buffers or things like
2630 that.
wdenk4a5c8a72003-03-06 00:02:04 +00002631
wdenk6c59edc2004-05-03 20:45:30 +00002632Having only the stack as writable memory limits means we cannot use
Jeremiah Mahler03f930c2015-01-04 18:56:50 -08002633normal global data to share information between the code. But it
wdenk6c59edc2004-05-03 20:45:30 +00002634turned out that the implementation of U-Boot can be greatly
2635simplified by making a global data structure (gd_t) available to all
2636functions. We could pass a pointer to this data as argument to _all_
2637functions, but this would bloat the code. Instead we use a feature of
2638the GCC compiler (Global Register Variables) to share the data: we
2639place a pointer (gd) to the global data into a register which we
2640reserve for this purpose.
wdenkc6097192002-11-03 00:24:07 +00002641
wdenk6c59edc2004-05-03 20:45:30 +00002642When choosing a register for such a purpose we are restricted by the
2643relevant (E)ABI specifications for the current architecture, and by
2644GCC's implementation.
wdenkc6097192002-11-03 00:24:07 +00002645
wdenk6c59edc2004-05-03 20:45:30 +00002646For PowerPC, the following registers have specific use:
2647 R1: stack pointer
Wolfgang Denk69c09642008-02-14 22:43:22 +01002648 R2: reserved for system use
wdenk6c59edc2004-05-03 20:45:30 +00002649 R3-R4: parameter passing and return values
2650 R5-R10: parameter passing
2651 R13: small data area pointer
2652 R30: GOT pointer
2653 R31: frame pointer
wdenkc6097192002-11-03 00:24:07 +00002654
Joakim Tjernlund693c0c12010-01-19 14:41:58 +01002655 (U-Boot also uses R12 as internal GOT pointer. r12
2656 is a volatile register so r12 needs to be reset when
2657 going back and forth between asm and C)
wdenkc6097192002-11-03 00:24:07 +00002658
Wolfgang Denk69c09642008-02-14 22:43:22 +01002659 ==> U-Boot will use R2 to hold a pointer to the global data
wdenkc6097192002-11-03 00:24:07 +00002660
wdenk6c59edc2004-05-03 20:45:30 +00002661 Note: on PPC, we could use a static initializer (since the
2662 address of the global data structure is known at compile time),
2663 but it turned out that reserving a register results in somewhat
2664 smaller code - although the code savings are not that big (on
2665 average for all boards 752 bytes for the whole U-Boot image,
2666 624 text + 127 data).
wdenkc6097192002-11-03 00:24:07 +00002667
wdenk6c59edc2004-05-03 20:45:30 +00002668On ARM, the following registers are used:
wdenkc6097192002-11-03 00:24:07 +00002669
wdenk6c59edc2004-05-03 20:45:30 +00002670 R0: function argument word/integer result
2671 R1-R3: function argument word
Jeroen Hofsteea556aca2013-09-21 14:04:42 +02002672 R9: platform specific
2673 R10: stack limit (used only if stack checking is enabled)
wdenk6c59edc2004-05-03 20:45:30 +00002674 R11: argument (frame) pointer
2675 R12: temporary workspace
2676 R13: stack pointer
2677 R14: link register
2678 R15: program counter
wdenkc6097192002-11-03 00:24:07 +00002679
Jeroen Hofsteea556aca2013-09-21 14:04:42 +02002680 ==> U-Boot will use R9 to hold a pointer to the global data
2681
2682 Note: on ARM, only R_ARM_RELATIVE relocations are supported.
wdenkc6097192002-11-03 00:24:07 +00002683
Thomas Chou8fa38582010-05-21 11:08:03 +08002684On Nios II, the ABI is documented here:
Naoki Hayamae0cc1852020-10-08 13:17:16 +09002685 https://www.altera.com/literature/hb/nios2/n2cpu_nii51016.pdf
Thomas Chou8fa38582010-05-21 11:08:03 +08002686
2687 ==> U-Boot will use gp to hold a pointer to the global data
2688
2689 Note: on Nios II, we give "-G0" option to gcc and don't use gp
2690 to access small data sections, so gp is free.
2691
Rick Chend7e6f922017-12-26 13:55:59 +08002692On RISC-V, the following registers are used:
2693
2694 x0: hard-wired zero (zero)
2695 x1: return address (ra)
2696 x2: stack pointer (sp)
2697 x3: global pointer (gp)
2698 x4: thread pointer (tp)
2699 x5: link register (t0)
2700 x8: frame pointer (fp)
2701 x10-x11: arguments/return values (a0-1)
2702 x12-x17: arguments (a2-7)
2703 x28-31: temporaries (t3-6)
2704 pc: program counter (pc)
2705
2706 ==> U-Boot will use gp to hold a pointer to the global data
2707
wdenk6c59edc2004-05-03 20:45:30 +00002708Memory Management:
2709------------------
wdenkc6097192002-11-03 00:24:07 +00002710
wdenk6c59edc2004-05-03 20:45:30 +00002711U-Boot runs in system state and uses physical addresses, i.e. the
2712MMU is not used either for address mapping nor for memory protection.
wdenkc6097192002-11-03 00:24:07 +00002713
wdenk6c59edc2004-05-03 20:45:30 +00002714The available memory is mapped to fixed addresses using the memory
2715controller. In this process, a contiguous block is formed for each
2716memory type (Flash, SDRAM, SRAM), even when it consists of several
2717physical memory banks.
wdenkc6097192002-11-03 00:24:07 +00002718
wdenk6c59edc2004-05-03 20:45:30 +00002719U-Boot is installed in the first 128 kB of the first Flash bank (on
2720TQM8xxL modules this is the range 0x40000000 ... 0x4001FFFF). After
2721booting and sizing and initializing DRAM, the code relocates itself
2722to the upper end of DRAM. Immediately below the U-Boot code some
Jean-Christophe PLAGNIOL-VILLARD03836942008-10-16 15:01:15 +02002723memory is reserved for use by malloc() [see CONFIG_SYS_MALLOC_LEN
wdenk6c59edc2004-05-03 20:45:30 +00002724configuration setting]. Below that, a structure with global Board
2725Info data is placed, followed by the stack (growing downward).
wdenkc6097192002-11-03 00:24:07 +00002726
wdenk6c59edc2004-05-03 20:45:30 +00002727Additionally, some exception handler code is copied to the low 8 kB
2728of DRAM (0x00000000 ... 0x00001FFF).
wdenkc6097192002-11-03 00:24:07 +00002729
wdenk6c59edc2004-05-03 20:45:30 +00002730So a typical memory configuration with 16 MB of DRAM could look like
2731this:
wdenkc6097192002-11-03 00:24:07 +00002732
wdenk6c59edc2004-05-03 20:45:30 +00002733 0x0000 0000 Exception Vector code
2734 :
2735 0x0000 1FFF
2736 0x0000 2000 Free for Application Use
2737 :
2738 :
wdenkc6097192002-11-03 00:24:07 +00002739
wdenk6c59edc2004-05-03 20:45:30 +00002740 :
2741 :
2742 0x00FB FF20 Monitor Stack (Growing downward)
2743 0x00FB FFAC Board Info Data and permanent copy of global data
2744 0x00FC 0000 Malloc Arena
2745 :
2746 0x00FD FFFF
2747 0x00FE 0000 RAM Copy of Monitor Code
2748 ... eventually: LCD or video framebuffer
2749 ... eventually: pRAM (Protected RAM - unchanged by reset)
2750 0x00FF FFFF [End of RAM]
wdenkc6097192002-11-03 00:24:07 +00002751
wdenkc6097192002-11-03 00:24:07 +00002752
wdenk6c59edc2004-05-03 20:45:30 +00002753System Initialization:
2754----------------------
wdenkc6097192002-11-03 00:24:07 +00002755
wdenk6c59edc2004-05-03 20:45:30 +00002756In the reset configuration, U-Boot starts at the reset entry point
Marcel Ziswilerabd8dcb2008-07-09 08:17:15 +02002757(on most PowerPC systems at address 0x00000100). Because of the reset
Jeremiah Mahler03f930c2015-01-04 18:56:50 -08002758configuration for CS0# this is a mirror of the on board Flash memory.
wdenk6c59edc2004-05-03 20:45:30 +00002759To be able to re-map memory U-Boot then jumps to its link address.
2760To be able to implement the initialization code in C, a (small!)
2761initial stack is set up in the internal Dual Ported RAM (in case CPUs
Heiko Schocher71cb3e92017-06-07 17:33:10 +02002762which provide such a feature like), or in a locked part of the data
2763cache. After that, U-Boot initializes the CPU core, the caches and
2764the SIU.
wdenkc6097192002-11-03 00:24:07 +00002765
wdenk6c59edc2004-05-03 20:45:30 +00002766Next, all (potentially) available memory banks are mapped using a
2767preliminary mapping. For example, we put them on 512 MB boundaries
2768(multiples of 0x20000000: SDRAM on 0x00000000 and 0x20000000, Flash
2769on 0x40000000 and 0x60000000, SRAM on 0x80000000). Then UPM A is
2770programmed for SDRAM access. Using the temporary configuration, a
2771simple memory test is run that determines the size of the SDRAM
2772banks.
wdenkc6097192002-11-03 00:24:07 +00002773
wdenk6c59edc2004-05-03 20:45:30 +00002774When there is more than one SDRAM bank, and the banks are of
2775different size, the largest is mapped first. For equal size, the first
2776bank (CS2#) is mapped first. The first mapping is always for address
27770x00000000, with any additional banks following immediately to create
2778contiguous memory starting from 0.
wdenkc6097192002-11-03 00:24:07 +00002779
wdenk6c59edc2004-05-03 20:45:30 +00002780Then, the monitor installs itself at the upper end of the SDRAM area
2781and allocates memory for use by malloc() and for the global Board
2782Info data; also, the exception vector code is copied to the low RAM
2783pages, and the final stack is set up.
wdenkc6097192002-11-03 00:24:07 +00002784
wdenk6c59edc2004-05-03 20:45:30 +00002785Only after this relocation will you have a "normal" C environment;
2786until that you are restricted in several ways, mostly because you are
2787running from ROM, and because the code will have to be relocated to a
2788new address in RAM.
wdenkc6097192002-11-03 00:24:07 +00002789
wdenkc6097192002-11-03 00:24:07 +00002790
wdenk6c59edc2004-05-03 20:45:30 +00002791U-Boot Porting Guide:
2792----------------------
wdenkc6097192002-11-03 00:24:07 +00002793
wdenk6c59edc2004-05-03 20:45:30 +00002794[Based on messages by Jerry Van Baren in the U-Boot-Users mailing
2795list, October 2002]
wdenkc6097192002-11-03 00:24:07 +00002796
wdenkc6097192002-11-03 00:24:07 +00002797
Jerry Van Barenba0687c2009-07-15 20:42:59 -04002798int main(int argc, char *argv[])
wdenk6c59edc2004-05-03 20:45:30 +00002799{
2800 sighandler_t no_more_time;
wdenkc6097192002-11-03 00:24:07 +00002801
Jerry Van Barenba0687c2009-07-15 20:42:59 -04002802 signal(SIGALRM, no_more_time);
2803 alarm(PROJECT_DEADLINE - toSec (3 * WEEK));
wdenkc6097192002-11-03 00:24:07 +00002804
wdenk6c59edc2004-05-03 20:45:30 +00002805 if (available_money > available_manpower) {
Jerry Van Barenba0687c2009-07-15 20:42:59 -04002806 Pay consultant to port U-Boot;
wdenk6c59edc2004-05-03 20:45:30 +00002807 return 0;
2808 }
wdenkc6097192002-11-03 00:24:07 +00002809
wdenk6c59edc2004-05-03 20:45:30 +00002810 Download latest U-Boot source;
wdenk34b613e2002-12-17 01:51:00 +00002811
Wolfgang Denk290ae6b2008-12-30 22:56:11 +01002812 Subscribe to u-boot mailing list;
wdenkc6097192002-11-03 00:24:07 +00002813
Jerry Van Barenba0687c2009-07-15 20:42:59 -04002814 if (clueless)
2815 email("Hi, I am new to U-Boot, how do I get started?");
wdenkc6097192002-11-03 00:24:07 +00002816
wdenk6c59edc2004-05-03 20:45:30 +00002817 while (learning) {
2818 Read the README file in the top level directory;
Naoki Hayamae0cc1852020-10-08 13:17:16 +09002819 Read https://www.denx.de/wiki/bin/view/DULG/Manual;
Patrick Delaunay9b281fa2020-02-28 15:18:10 +01002820 Read applicable doc/README.*;
wdenk6c59edc2004-05-03 20:45:30 +00002821 Read the source, Luke;
Jerry Van Barenba0687c2009-07-15 20:42:59 -04002822 /* find . -name "*.[chS]" | xargs grep -i <keyword> */
wdenk6c59edc2004-05-03 20:45:30 +00002823 }
wdenkc6097192002-11-03 00:24:07 +00002824
Jerry Van Barenba0687c2009-07-15 20:42:59 -04002825 if (available_money > toLocalCurrency ($2500))
2826 Buy a BDI3000;
2827 else
wdenk6c59edc2004-05-03 20:45:30 +00002828 Add a lot of aggravation and time;
wdenkc6097192002-11-03 00:24:07 +00002829
Jerry Van Barenba0687c2009-07-15 20:42:59 -04002830 if (a similar board exists) { /* hopefully... */
2831 cp -a board/<similar> board/<myboard>
2832 cp include/configs/<similar>.h include/configs/<myboard>.h
2833 } else {
2834 Create your own board support subdirectory;
2835 Create your own board include/configs/<myboard>.h file;
2836 }
2837 Edit new board/<myboard> files
2838 Edit new include/configs/<myboard>.h
wdenkc6097192002-11-03 00:24:07 +00002839
Jerry Van Barenba0687c2009-07-15 20:42:59 -04002840 while (!accepted) {
2841 while (!running) {
2842 do {
2843 Add / modify source code;
2844 } until (compiles);
2845 Debug;
2846 if (clueless)
2847 email("Hi, I am having problems...");
2848 }
2849 Send patch file to the U-Boot email list;
2850 if (reasonable critiques)
2851 Incorporate improvements from email list code review;
2852 else
2853 Defend code as written;
wdenk634d2f72004-04-15 23:14:49 +00002854 }
wdenkc6097192002-11-03 00:24:07 +00002855
wdenk6c59edc2004-05-03 20:45:30 +00002856 return 0;
2857}
wdenkc6097192002-11-03 00:24:07 +00002858
wdenk6c59edc2004-05-03 20:45:30 +00002859void no_more_time (int sig)
2860{
2861 hire_a_guru();
2862}
wdenkc6097192002-11-03 00:24:07 +00002863
wdenkc6097192002-11-03 00:24:07 +00002864
wdenk6c59edc2004-05-03 20:45:30 +00002865Coding Standards:
2866-----------------
wdenkc6097192002-11-03 00:24:07 +00002867
wdenk6c59edc2004-05-03 20:45:30 +00002868All contributions to U-Boot should conform to the Linux kernel
Baruch Siachb1081252017-12-10 17:34:35 +02002869coding style; see the kernel coding style guide at
2870https://www.kernel.org/doc/html/latest/process/coding-style.html, and the
2871script "scripts/Lindent" in your Linux kernel source directory.
Detlev Zundelaa63d482006-09-01 15:39:02 +02002872
2873Source files originating from a different project (for example the
2874MTD subsystem) are generally exempt from these guidelines and are not
Jeremiah Mahler03f930c2015-01-04 18:56:50 -08002875reformatted to ease subsequent migration to newer versions of those
Detlev Zundelaa63d482006-09-01 15:39:02 +02002876sources.
wdenkc6097192002-11-03 00:24:07 +00002877
Detlev Zundelaa63d482006-09-01 15:39:02 +02002878Please note that U-Boot is implemented in C (and to some small parts in
2879Assembler); no C++ is used, so please do not use C++ style comments (//)
2880in your code.
wdenkad276f22004-01-04 16:28:35 +00002881
wdenk6c59edc2004-05-03 20:45:30 +00002882Please also stick to the following formatting rules:
2883- remove any trailing white space
Wolfgang Denk20bd2a62011-07-27 10:59:55 +00002884- use TAB characters for indentation and vertical alignment, not spaces
wdenk6c59edc2004-05-03 20:45:30 +00002885- make sure NOT to use DOS '\r\n' line feeds
Wolfgang Denk20bd2a62011-07-27 10:59:55 +00002886- do not add more than 2 consecutive empty lines to source files
wdenk6c59edc2004-05-03 20:45:30 +00002887- do not add trailing empty lines to source files
wdenkc6097192002-11-03 00:24:07 +00002888
wdenk6c59edc2004-05-03 20:45:30 +00002889Submissions which do not conform to the standards may be returned
2890with a request to reformat the changes.
wdenkc6097192002-11-03 00:24:07 +00002891
wdenkc6097192002-11-03 00:24:07 +00002892
wdenk6c59edc2004-05-03 20:45:30 +00002893Submitting Patches:
2894-------------------
wdenkc6097192002-11-03 00:24:07 +00002895
wdenk6c59edc2004-05-03 20:45:30 +00002896Since the number of patches for U-Boot is growing, we need to
2897establish some rules. Submissions which do not conform to these rules
2898may be rejected, even when they contain important and valuable stuff.
wdenkc6097192002-11-03 00:24:07 +00002899
Naoki Hayamae0cc1852020-10-08 13:17:16 +09002900Please see https://www.denx.de/wiki/U-Boot/Patches for details.
Wolfgang Denkb240aef2008-03-26 10:40:12 +01002901
Wolfgang Denk290ae6b2008-12-30 22:56:11 +01002902Patches shall be sent to the u-boot mailing list <u-boot@lists.denx.de>;
S. Lockwood-Childsda6d34c2017-11-14 22:56:42 -08002903see https://lists.denx.de/listinfo/u-boot
Wolfgang Denk290ae6b2008-12-30 22:56:11 +01002904
wdenk6c59edc2004-05-03 20:45:30 +00002905When you send a patch, please include the following information with
2906it:
wdenkc6097192002-11-03 00:24:07 +00002907
wdenk6c59edc2004-05-03 20:45:30 +00002908* For bug fixes: a description of the bug and how your patch fixes
2909 this bug. Please try to include a way of demonstrating that the
2910 patch actually fixes something.
wdenkc6097192002-11-03 00:24:07 +00002911
wdenk6c59edc2004-05-03 20:45:30 +00002912* For new features: a description of the feature and your
2913 implementation.
wdenkc6097192002-11-03 00:24:07 +00002914
Robert P. J. Day076ed9b2015-12-19 07:16:10 -05002915* For major contributions, add a MAINTAINERS file with your
2916 information and associated file and directory references.
wdenkc6097192002-11-03 00:24:07 +00002917
Albert ARIBAUD48e910f2013-09-11 15:52:51 +02002918* When you add support for a new board, don't forget to add a
2919 maintainer e-mail address to the boards.cfg file, too.
wdenkc6097192002-11-03 00:24:07 +00002920
wdenk6c59edc2004-05-03 20:45:30 +00002921* If your patch adds new configuration options, don't forget to
2922 document these in the README file.
wdenkc6097192002-11-03 00:24:07 +00002923
Wolfgang Denkb240aef2008-03-26 10:40:12 +01002924* The patch itself. If you are using git (which is *strongly*
2925 recommended) you can easily generate the patch using the
Wolfgang Denk20bd2a62011-07-27 10:59:55 +00002926 "git format-patch". If you then use "git send-email" to send it to
Wolfgang Denkb240aef2008-03-26 10:40:12 +01002927 the U-Boot mailing list, you will avoid most of the common problems
2928 with some other mail clients.
wdenkca9bc762003-07-15 07:45:49 +00002929
Wolfgang Denkb240aef2008-03-26 10:40:12 +01002930 If you cannot use git, use "diff -purN OLD NEW". If your version of
2931 diff does not support these options, then get the latest version of
2932 GNU diff.
wdenkc6097192002-11-03 00:24:07 +00002933
Wolfgang Denkb240aef2008-03-26 10:40:12 +01002934 The current directory when running this command shall be the parent
2935 directory of the U-Boot source tree (i. e. please make sure that
2936 your patch includes sufficient directory information for the
2937 affected files).
2938
2939 We prefer patches as plain text. MIME attachments are discouraged,
2940 and compressed attachments must not be used.
wdenk88e72a32003-06-19 23:04:19 +00002941
wdenk6c59edc2004-05-03 20:45:30 +00002942* If one logical set of modifications affects or creates several
2943 files, all these changes shall be submitted in a SINGLE patch file.
wdenk57b2d802003-06-27 21:31:46 +00002944
wdenk6c59edc2004-05-03 20:45:30 +00002945* Changesets that contain different, unrelated modifications shall be
2946 submitted as SEPARATE patches, one patch per changeset.
wdenk88e72a32003-06-19 23:04:19 +00002947
wdenkc6097192002-11-03 00:24:07 +00002948
wdenk6c59edc2004-05-03 20:45:30 +00002949Notes:
wdenkc6097192002-11-03 00:24:07 +00002950
Simon Glassdc27def2016-07-27 20:33:08 -06002951* Before sending the patch, run the buildman script on your patched
wdenk6c59edc2004-05-03 20:45:30 +00002952 source tree and make sure that no errors or warnings are reported
2953 for any of the boards.
2954
2955* Keep your modifications to the necessary minimum: A patch
2956 containing several unrelated changes or arbitrary reformats will be
2957 returned with a request to re-formatting / split it.
wdenkc6097192002-11-03 00:24:07 +00002958
wdenk6c59edc2004-05-03 20:45:30 +00002959* If you modify existing code, make sure that your new code does not
2960 add to the memory footprint of the code ;-) Small is beautiful!
2961 When adding new features, these should compile conditionally only
2962 (using #ifdef), and the resulting code with the new feature
2963 disabled must not need more memory than the old code without your
2964 modification.
wdenkcbc49a52005-05-03 14:12:25 +00002965
Wolfgang Denk290ae6b2008-12-30 22:56:11 +01002966* Remember that there is a size limit of 100 kB per message on the
2967 u-boot mailing list. Bigger patches will be moderated. If they are
2968 reasonable and not too big, they will be acknowledged. But patches
2969 bigger than the size limit should be avoided.