blob: 186f1f9a5ffb8161c51cfdf4e72daaf5d0e8c97b [file] [log] [blame]
Tom Rini83d290c2018-05-06 17:58:06 -04001# SPDX-License-Identifier: GPL-2.0+
wdenkc6097192002-11-03 00:24:07 +00002#
Wolfgang Denkeca3aeb2013-06-21 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
wdenke86e5a02004-10-17 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. Day7207b362015-12-19 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. Day7207b362015-12-19 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. Dayadb9d852012-11-14 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. Day7207b362015-12-19 07:16:10 -050051U-Boot, you should send a message to the U-Boot mailing list at
Peter Tyser0c325652008-09-10 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 Hayama6681bbb2020-10-08 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 Denk218ca722008-03-26 10:40:12 +010057Where to get source code:
58=========================
59
Robert P. J. Day7207b362015-12-19 07:16:10 -050060The U-Boot source code is maintained in the Git repository at
Heinrich Schuchardta3bbd0b2021-02-24 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 Denk218ca722008-03-26 10:40:12 +010063
Naoki Hayamac4bd51e2020-10-08 13:16:25 +090064The "Tags" links on this page allow you to download tarballs of
Marcel Ziswiler11ccc332008-07-09 08:17:15 +020065any version you might be interested in. Official releases are also
Naoki Hayamac4bd51e2020-10-08 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 Denk218ca722008-03-26 10:40:12 +010069
70
wdenkc6097192002-11-03 00:24:07 +000071Where we come from:
72===================
73
74- start from 8xxrom sources
Naoki Hayama047f6ec2020-10-08 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 Glass9e5616d2019-08-01 09:47:14 -060083 * ATA disk / SCSI ... boot
Naoki Hayama047f6ec2020-10-08 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 Hayama047f6ec2020-10-08 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:
107
108 U_BOOT_VERSION u_boot_logo
109 IH_OS_U_BOOT u_boot_hush_start
wdenkc6097192002-11-03 00:24:07 +0000110
111
wdenk93f19cc2002-12-17 17:55:09 +0000112Versioning:
113===========
114
Thomas Weber360d8832010-09-28 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.
wdenk93f19cc2002-12-17 17:55:09 +0000121
Thomas Weber360d8832010-09-28 08:06:25 +0200122Examples:
Wolfgang Denkc0f40852011-10-26 10:21:21 +0000123 U-Boot v2009.11 - Release November 2009
Thomas Weber360d8832010-09-28 08:06:25 +0200124 U-Boot v2009.11.1 - Release 1 in version November 2009 stable tree
Jelle van der Waa0de21ec2016-10-30 17:30:30 +0100125 U-Boot v2010.09-rc1 - Release candidate 1 for September 2010 release
wdenk93f19cc2002-12-17 17:55:09 +0000126
127
wdenkc6097192002-11-03 00:24:07 +0000128Directory Hierarchy:
129====================
130
Simon Glass6e73ed02021-07-10 21:14:21 -0600131/arch Architecture-specific files
Masahiro Yamada6eae68e2014-03-07 18:02:02 +0900132 /arc Files generic to ARC architecture
Peter Tyser8d321b82010-04-12 22:28:21 -0500133 /arm Files generic to ARM architecture
Peter Tyser8d321b82010-04-12 22:28:21 -0500134 /m68k Files generic to m68k architecture
Peter Tyser8d321b82010-04-12 22:28:21 -0500135 /microblaze Files generic to microblaze architecture
Peter Tyser8d321b82010-04-12 22:28:21 -0500136 /mips Files generic to MIPS architecture
Peter Tyser8d321b82010-04-12 22:28:21 -0500137 /nios2 Files generic to Altera NIOS2 architecture
Stefan Roesea47a12b2010-04-15 16:07:28 +0200138 /powerpc Files generic to PowerPC architecture
Rick Chen3fafced2017-12-26 13:55:59 +0800139 /riscv Files generic to RISC-V architecture
Robert P. J. Day7207b362015-12-19 07:16:10 -0500140 /sandbox Files generic to HW-independent "sandbox"
Peter Tyser8d321b82010-04-12 22:28:21 -0500141 /sh Files generic to SH architecture
Robert P. J. Day33c77312013-09-15 18:34:15 -0400142 /x86 Files generic to x86 architecture
Naoki Hayamae4eb3132020-10-08 13:16:38 +0900143 /xtensa Files generic to Xtensa architecture
Simon Glass6e73ed02021-07-10 21:14:21 -0600144/api Machine/arch-independent API for external apps
145/board Board-dependent files
Simon Glass19a91f22021-10-14 12:47:54 -0600146/boot Support for images and booting
Xu Ziyuan740f7e52016-08-26 19:54:49 +0800147/cmd U-Boot commands functions
Simon Glass6e73ed02021-07-10 21:14:21 -0600148/common Misc architecture-independent functions
Robert P. J. Day7207b362015-12-19 07:16:10 -0500149/configs Board default configuration files
Peter Tyser8d321b82010-04-12 22:28:21 -0500150/disk Code for disk drive partition handling
Simon Glass6e73ed02021-07-10 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 Tyser8d321b82010-04-12 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. Day7207b362015-12-19 07:16:10 -0500158/lib Library routines generic to all architectures
159/Licenses Various license files
Peter Tyser8d321b82010-04-12 22:28:21 -0500160/net Networking code
161/post Power On Self Test
Robert P. J. Day7207b362015-12-19 07:16:10 -0500162/scripts Various build scripts and Makefiles
163/test Various unit test files
Simon Glass6e73ed02021-07-10 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 Freytherab584d62014-08-04 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 Freytherab584d62014-08-04 09:26:05 +0200178 make TQM823L_defconfig
wdenkc6097192002-11-03 00:24:07 +0000179
Robert P. J. Day7207b362015-12-19 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 Glass75b3c3a2014-03-22 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 Hayamabbb140e2020-10-08 13:16:58 +0900192See doc/arch/sandbox.rst for more details.
Simon Glass75b3c3a2014-03-22 17:12:59 -0600193
194
Simon Glassdb910352015-03-03 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. Day7207b362015-12-19 07:16:10 -0500199SPL and U-Boot proper (i.e. they both follow the same rules).
Simon Glassdb910352015-03-03 08:03:00 -0700200
Robert P. J. Day7207b362015-12-19 07:16:10 -0500201Note: "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.
208
209Execution 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 Glassdb910352015-03-03 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 Hayama499696e2020-09-24 15:57:19 +0900246 - there is no need to clear BSS, it will be done by crt0.S
Andreas Dannenberg14254652019-08-08 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 Glassdb910352015-03-03 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 Kumar63b23162017-08-11 11:09:14 +0530275 CONFIG_SYS_FSL_HAS_CCI400
276
277 Defined For SoC that has cache coherent interconnect
278 CCN-400
wdenk7f6c2cb2002-11-10 22:06:23 +0000279
Ashish Kumarc055cee2017-08-18 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 Phillips26281142007-08-10 13:28:25 -0500286- CPU Type: Define exactly one, e.g. CONFIG_MPC85XX.
wdenkc6097192002-11-03 00:24:07 +0000287
Kim Phillips26281142007-08-10 13:28:25 -0500288- Board Type: Define exactly one, e.g. CONFIG_MPC8540ADS.
Wolfgang Denk6ccec442006-10-24 14:42:37 +0200289
Kumar Gala66412c62011-02-18 05:40:54 -0600290- 85xx CPU Options:
York Sunffd06e02012-10-08 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 Wood33eee332012-08-14 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
301 CONFIG_SYS_FSL_CORENET_SNOOPVEC_COREONLY must be set.
302
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
317 CONFIG_SYS_FSL_CORENET_SNOOPVEC_COREONLY
318
319 This is the value to write into CCSR offset 0x18600
320 according to the A004510 workaround.
321
Priyanka Jainb1359912013-12-17 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 Schwierzeck6cb461b2012-04-02 02:57:56 +0000327- Generic CPU options:
Daniel Schwierzeck6cb461b2012-04-02 02:57:56 +0000328
York Sun5614e712013-09-30 09:22:09 -0700329 CONFIG_SYS_FSL_DDR
330 Freescale DDR driver in use. This type of DDR controller is
Tom Rini1c588572021-05-14 21:34:26 -0400331 found in mpc83xx, mpc85xx as well as some ARM core SoCs.
York Sun5614e712013-09-30 09:22:09 -0700332
333 CONFIG_SYS_FSL_DDR_ADDR
334 Freescale DDR memory-mapped register base.
335
Prabhakar Kushwaha1c407072017-02-02 15:01:26 +0530336 CONFIG_SYS_FSL_IFC_CLK_DIV
337 Defines divider of platform clock(clock input to IFC controller).
338
Prabhakar Kushwahaadd63f92017-02-02 15:02:00 +0530339 CONFIG_SYS_FSL_LBC_CLK_DIV
340 Defines divider of platform clock(clock input to eLBC controller).
341
York Sun6b9e3092014-02-10 13:59:43 -0800342 CONFIG_SYS_FSL_DDR_SDRAM_BASE_PHY
343 Physical address from the view of DDR controllers. It is the
344 same as CONFIG_SYS_DDR_SDRAM_BASE for all Power SoCs. But
345 it could be different for ARM SoCs.
346
Daniel Schwierzeck92bbd642011-07-27 13:22:39 +0200347- MIPS CPU options:
Daniel Schwierzeck92bbd642011-07-27 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 Rieschb67d8812012-02-02 00:44:39 +0000354- ARM options:
355 CONFIG_SYS_EXCEPTION_VECTORS_HIGH
356
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 Sun207774b2015-03-20 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 Warren73c38932015-01-19 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
wdenk5da627a2003-10-09 20:09:04 +0000375- Linux Kernel Interface:
wdenk5da627a2003-10-09 20:09:04 +0000376 CONFIG_MEMSIZE_IN_BYTES [relevant for MIPS only]
377
Jeremiah Mahlerb445bbb2015-01-04 18:56:50 -0800378 When transferring memsize parameter to Linux, some versions
wdenk5da627a2003-10-09 20:09:04 +0000379 expect it to be in bytes, others in MB.
380 Define CONFIG_MEMSIZE_IN_BYTES to make it in bytes.
381
Gerald Van Barenfec6d9e2008-06-03 20:34:45 -0400382 CONFIG_OF_LIBFDT
Wolfgang Denkf57f70a2005-10-13 01:45:54 +0200383
384 New kernel versions are expecting firmware settings to be
Gerald Van Baren213bf8c2007-03-31 12:23:51 -0400385 passed using flattened device trees (based on open firmware
386 concepts).
387
388 CONFIG_OF_LIBFDT
389 * New libfdt-based support
390 * Adds the "fdt" command
Kim Phillips3bb342f2007-08-10 14:34:14 -0500391 * The bootm command automatically updates the fdt
Gerald Van Baren213bf8c2007-03-31 12:23:51 -0400392
Wolfgang Denkf57f70a2005-10-13 01:45:54 +0200393 OF_TBCLK - The timebase frequency.
394
Marcel Ziswiler11ccc332008-07-09 08:17:15 +0200395 boards with QUICC Engines require OF_QE to set UCC MAC
396 addresses
Kim Phillips3bb342f2007-08-10 14:34:14 -0500397
Heiko Schocher3887c3f2009-09-23 07:56:08 +0200398 CONFIG_OF_IDE_FIXUP
399
400 U-Boot can detect if an IDE device is present or not.
401 If not, and this new config option is activated, U-Boot
402 removes the ATA node from the DTS before booting Linux,
403 so the Linux IDE driver does not probe the device and
404 crash. This is needed for buggy hardware (uc101) where
405 no pull down resistor is connected to the signal IDE5V_DD7.
406
Niklaus Giger0b2f4ec2008-11-03 22:13:47 +0100407- vxWorks boot parameters:
408
409 bootvx constructs a valid bootline using the following
Bin Meng9e98b7e2015-10-07 20:19:17 -0700410 environments variables: bootdev, bootfile, ipaddr, netmask,
411 serverip, gatewayip, hostname, othbootargs.
Niklaus Giger0b2f4ec2008-11-03 22:13:47 +0100412 It loads the vxWorks image pointed bootfile.
413
Naoki Hayama81a05d92020-10-08 13:17:08 +0900414 Note: If a "bootargs" environment is defined, it will override
Niklaus Giger0b2f4ec2008-11-03 22:13:47 +0100415 the defaults discussed just above.
416
Aneesh V93bc2192011-06-16 23:30:51 +0000417- Cache Configuration for ARM:
Aneesh V93bc2192011-06-16 23:30:51 +0000418 CONFIG_SYS_PL310_BASE - Physical base address of PL310
419 controller register space
420
wdenk6705d812004-08-02 23:22:59 +0000421- Serial Ports:
wdenk6705d812004-08-02 23:22:59 +0000422 CONFIG_PL011_CLOCK
423
424 If you have Amba PrimeCell PL011 UARTs, set this variable to
425 the clock speed of the UARTs.
426
427 CONFIG_PL01x_PORTS
428
429 If you have Amba PrimeCell PL010 or PL011 UARTs on your board,
430 define this to a list of base addresses for each (supported)
431 port. See e.g. include/configs/versatile.h
432
Karicheri, Muralidharand57dee52014-04-09 15:38:46 -0400433 CONFIG_SERIAL_HW_FLOW_CONTROL
434
435 Define this variable to enable hw flow control in serial driver.
436 Current user of this option is drivers/serial/nsl16550.c driver
wdenk6705d812004-08-02 23:22:59 +0000437
wdenkc6097192002-11-03 00:24:07 +0000438- Serial Download Echo Mode:
439 CONFIG_LOADS_ECHO
440 If defined to 1, all characters received during a
441 serial download (using the "loads" command) are
442 echoed back. This might be needed by some terminal
443 emulations (like "cu"), but may as well just take
444 time on others. This setting #define's the initial
445 value of the "loads_echo" environment variable.
446
Simon Glass302a6482016-03-13 19:07:28 -0600447- Removal of commands
448 If no commands are needed to boot, you can disable
449 CONFIG_CMDLINE to remove them. In this case, the command line
450 will not be available, and when U-Boot wants to execute the
451 boot command (on start-up) it will call board_run_command()
452 instead. This can reduce image size significantly for very
453 simple boot procedures.
454
Wolfgang Denka5ecbe62013-03-23 23:50:31 +0000455- Regular expression support:
456 CONFIG_REGEX
Wolfgang Denk93e14592013-10-04 17:43:24 +0200457 If this variable is defined, U-Boot is linked against
458 the SLRE (Super Light Regular Expression) library,
459 which adds regex support to some commands, as for
460 example "env grep" and "setexpr".
Wolfgang Denka5ecbe62013-03-23 23:50:31 +0000461
wdenkc6097192002-11-03 00:24:07 +0000462- Watchdog:
Rasmus Villemoes933ada52021-04-14 09:18:22 +0200463 CONFIG_SYS_WATCHDOG_FREQ
464 Some platforms automatically call WATCHDOG_RESET()
465 from the timer interrupt handler every
466 CONFIG_SYS_WATCHDOG_FREQ interrupts. If not set by the
467 board configuration file, a default of CONFIG_SYS_HZ/2
468 (i.e. 500) is used. Setting CONFIG_SYS_WATCHDOG_FREQ
469 to 0 disables calling WATCHDOG_RESET() from the timer
470 interrupt.
471
wdenkc6097192002-11-03 00:24:07 +0000472- Real-Time Clock:
473
Jon Loeliger602ad3b2007-06-11 19:03:39 -0500474 When CONFIG_CMD_DATE is selected, the type of the RTC
wdenkc6097192002-11-03 00:24:07 +0000475 has to be selected, too. Define exactly one of the
476 following options:
477
wdenkc6097192002-11-03 00:24:07 +0000478 CONFIG_RTC_PCF8563 - use Philips PCF8563 RTC
Fabio Estevam4e8b7542011-10-24 06:44:15 +0000479 CONFIG_RTC_MC13XXX - use MC13783 or MC13892 RTC
wdenkc6097192002-11-03 00:24:07 +0000480 CONFIG_RTC_MC146818 - use MC146818 RTC
wdenk1cb8e982003-03-06 21:55:29 +0000481 CONFIG_RTC_DS1307 - use Maxim, Inc. DS1307 RTC
wdenkc6097192002-11-03 00:24:07 +0000482 CONFIG_RTC_DS1337 - use Maxim, Inc. DS1337 RTC
wdenk7f70e852003-05-20 14:25:27 +0000483 CONFIG_RTC_DS1338 - use Maxim, Inc. DS1338 RTC
Markus Niebel412921d2014-07-21 11:06:16 +0200484 CONFIG_RTC_DS1339 - use Maxim, Inc. DS1339 RTC
wdenk3bac3512003-03-12 10:41:04 +0000485 CONFIG_RTC_DS164x - use Dallas DS164x RTC
Tor Krill9536dfc2008-03-15 15:40:26 +0100486 CONFIG_RTC_ISL1208 - use Intersil ISL1208 RTC
wdenk4c0d4c32004-06-09 17:34:58 +0000487 CONFIG_RTC_MAX6900 - use Maxim, Inc. MAX6900 RTC
Chris Packham2bd3cab2017-05-30 12:03:33 +1200488 CONFIG_RTC_DS1337_NOOSC - Turn off the OSC output for DS1337
Heiko Schocher71d19f32011-03-28 09:24:22 +0200489 CONFIG_SYS_RV3029_TCR - enable trickle charger on
490 RV3029 RTC.
wdenkc6097192002-11-03 00:24:07 +0000491
wdenkb37c7e52003-06-30 16:24:52 +0000492 Note that if the RTC uses I2C, then the I2C interface
493 must also be configured. See I2C Support, below.
494
Peter Tysere92739d2008-12-17 16:36:21 -0600495- GPIO Support:
496 CONFIG_PCA953X - use NXP's PCA953X series I2C GPIO
Peter Tysere92739d2008-12-17 16:36:21 -0600497
Chris Packham5dec49c2010-12-19 10:12:13 +0000498 The CONFIG_SYS_I2C_PCA953X_WIDTH option specifies a list of
499 chip-ngpio pairs that tell the PCA953X driver the number of
500 pins supported by a particular chip.
501
Peter Tysere92739d2008-12-17 16:36:21 -0600502 Note that if the GPIO device uses I2C, then the I2C interface
503 must also be configured. See I2C Support, below.
504
Simon Glassaa532332014-06-11 23:29:41 -0600505- I/O tracing:
506 When CONFIG_IO_TRACE is selected, U-Boot intercepts all I/O
507 accesses and can checksum them or write a list of them out
508 to memory. See the 'iotrace' command for details. This is
509 useful for testing device drivers since it can confirm that
510 the driver behaves the same way before and after a code
511 change. Currently this is supported on sandbox and arm. To
512 add support for your architecture, add '#include <iotrace.h>'
513 to the bottom of arch/<arch>/include/asm/io.h and test.
514
515 Example output from the 'iotrace stats' command is below.
516 Note that if the trace buffer is exhausted, the checksum will
517 still continue to operate.
518
519 iotrace is enabled
520 Start: 10000000 (buffer start address)
521 Size: 00010000 (buffer size)
522 Offset: 00000120 (current buffer offset)
523 Output: 10000120 (start + offset)
524 Count: 00000018 (number of trace records)
525 CRC32: 9526fb66 (CRC32 of all trace records)
526
wdenkc6097192002-11-03 00:24:07 +0000527- Timestamp Support:
528
wdenk43d96162003-03-06 00:02:04 +0000529 When CONFIG_TIMESTAMP is selected, the timestamp
530 (date and time) of an image is printed by image
531 commands like bootm or iminfo. This option is
Jon Loeliger602ad3b2007-06-11 19:03:39 -0500532 automatically enabled when you select CONFIG_CMD_DATE .
wdenkc6097192002-11-03 00:24:07 +0000533
Karl O. Pinc923c46f2012-08-16 06:20:15 +0000534- Partition Labels (disklabels) Supported:
535 Zero or more of the following:
536 CONFIG_MAC_PARTITION Apple's MacOS partition table.
Karl O. Pinc923c46f2012-08-16 06:20:15 +0000537 CONFIG_ISO_PARTITION ISO partition table, used on CDROM etc.
538 CONFIG_EFI_PARTITION GPT partition table, common when EFI is the
539 bootloader. Note 2TB partition limit; see
540 disk/part_efi.c
Simon Glassc649e3c2016-05-01 11:36:02 -0600541 CONFIG_SCSI) you must configure support for at
Karl O. Pinc923c46f2012-08-16 06:20:15 +0000542 least one non-MTD partition type as well.
wdenkc6097192002-11-03 00:24:07 +0000543
wdenkc6097192002-11-03 00:24:07 +0000544- NETWORK Support (PCI):
Kyle Moffettce5207e2011-10-18 11:05:29 +0000545 CONFIG_E1000_SPI
546 Utility code for direct access to the SPI bus on Intel 8257x.
547 This does not do anything useful unless you set at least one
548 of CONFIG_CMD_E1000 or CONFIG_E1000_SPI_GENERIC.
549
wdenkc6097192002-11-03 00:24:07 +0000550 CONFIG_NATSEMI
551 Support for National dp83815 chips.
552
553 CONFIG_NS8382X
554 Support for National dp8382[01] gigabit chips.
555
wdenk45219c42003-05-12 21:50:16 +0000556- NETWORK Support (other):
Rob Herringefdd7312011-12-15 11:15:49 +0000557 CONFIG_CALXEDA_XGMAC
558 Support for the Calxeda XGMAC device
559
Ashok3bb46d22012-10-15 06:20:47 +0000560 CONFIG_LAN91C96
wdenk45219c42003-05-12 21:50:16 +0000561 Support for SMSC's LAN91C96 chips.
562
wdenk45219c42003-05-12 21:50:16 +0000563 CONFIG_LAN91C96_USE_32_BIT
564 Define this to enable 32 bit addressing
565
Heiko Schocherdc02bad2011-11-15 10:00:04 -0500566 CONFIG_SYS_DAVINCI_EMAC_PHY_COUNT
567 Define this if you have more then 3 PHYs.
568
Macpaul Linb3dbf4a52010-12-21 16:59:46 +0800569 CONFIG_FTGMAC100
570 Support for Faraday's FTGMAC100 Gigabit SoC Ethernet
571
572 CONFIG_FTGMAC100_EGIGA
573 Define this to use GE link update with gigabit PHY.
574 Define this if FTGMAC100 is connected to gigabit PHY.
575 If your system has 10/100 PHY only, it might not occur
576 wrong behavior. Because PHY usually return timeout or
577 useless data when polling gigabit status and gigabit
578 control registers. This behavior won't affect the
579 correctnessof 10/100 link speed update.
580
Yoshihiro Shimoda3d0075f2011-01-27 10:06:03 +0900581 CONFIG_SH_ETHER
582 Support for Renesas on-chip Ethernet controller
583
584 CONFIG_SH_ETHER_USE_PORT
585 Define the number of ports to be used
586
587 CONFIG_SH_ETHER_PHY_ADDR
588 Define the ETH PHY's address
589
Yoshihiro Shimoda68260aa2011-01-27 10:06:08 +0900590 CONFIG_SH_ETHER_CACHE_WRITEBACK
591 If this option is set, the driver enables cache flush.
592
Vadim Bendebury5e124722011-10-17 08:36:14 +0000593- TPM Support:
Che-liang Chiou90899cc2013-04-12 11:04:34 +0000594 CONFIG_TPM
595 Support TPM devices.
596
Christophe Ricard0766ad22015-10-06 22:54:41 +0200597 CONFIG_TPM_TIS_INFINEON
598 Support for Infineon i2c bus TPM devices. Only one device
Tom Wai-Hong Tam1b393db2013-04-12 11:04:37 +0000599 per system is supported at this time.
600
Tom Wai-Hong Tam1b393db2013-04-12 11:04:37 +0000601 CONFIG_TPM_TIS_I2C_BURST_LIMITATION
602 Define the burst count bytes upper limit
603
Christophe Ricard3aa74082016-01-21 23:27:13 +0100604 CONFIG_TPM_ST33ZP24
605 Support for STMicroelectronics TPM devices. Requires DM_TPM support.
606
607 CONFIG_TPM_ST33ZP24_I2C
608 Support for STMicroelectronics ST33ZP24 I2C devices.
609 Requires TPM_ST33ZP24 and I2C.
610
Christophe Ricardb75fdc12016-01-21 23:27:14 +0100611 CONFIG_TPM_ST33ZP24_SPI
612 Support for STMicroelectronics ST33ZP24 SPI devices.
613 Requires TPM_ST33ZP24 and SPI.
614
Dirk Eibachc01939c2013-06-26 15:55:15 +0200615 CONFIG_TPM_ATMEL_TWI
616 Support for Atmel TWI TPM device. Requires I2C support.
617
Che-liang Chiou90899cc2013-04-12 11:04:34 +0000618 CONFIG_TPM_TIS_LPC
Vadim Bendebury5e124722011-10-17 08:36:14 +0000619 Support for generic parallel port TPM devices. Only one device
620 per system is supported at this time.
621
622 CONFIG_TPM_TIS_BASE_ADDRESS
623 Base address where the generic TPM device is mapped
624 to. Contemporary x86 systems usually map it at
625 0xfed40000.
626
Reinhard Pfaube6c1522013-06-26 15:55:13 +0200627 CONFIG_TPM
628 Define this to enable the TPM support library which provides
629 functional interfaces to some TPM commands.
630 Requires support for a TPM device.
631
632 CONFIG_TPM_AUTH_SESSIONS
633 Define this to enable authorized functions in the TPM library.
634 Requires CONFIG_TPM and CONFIG_SHA1.
635
wdenkc6097192002-11-03 00:24:07 +0000636- USB Support:
637 At the moment only the UHCI host controller is
Heiko Schocher064b55c2017-06-14 05:49:40 +0200638 supported (PIP405, MIP405); define
wdenkc6097192002-11-03 00:24:07 +0000639 CONFIG_USB_UHCI to enable it.
640 define CONFIG_USB_KEYBOARD to enable the USB Keyboard
wdenk30d56fa2004-10-09 22:44:59 +0000641 and define CONFIG_USB_STORAGE to enable the USB
wdenkc6097192002-11-03 00:24:07 +0000642 storage devices.
643 Note:
644 Supported are USB Keyboards and USB Floppy drives
645 (TEAC FD-05PUB).
wdenk4d13cba2004-03-14 14:09:05 +0000646
Oleksandr Tymoshenko6e9e0622014-02-01 21:51:25 -0700647 CONFIG_USB_DWC2_REG_ADDR the physical CPU address of the DWC2
648 HW module registers.
649
Wolfgang Denk16c8d5e2006-06-14 17:45:53 +0200650- USB Device:
651 Define the below if you wish to use the USB console.
652 Once firmware is rebuilt from a serial console issue the
653 command "setenv stdin usbtty; setenv stdout usbtty" and
Marcel Ziswiler11ccc332008-07-09 08:17:15 +0200654 attach your USB cable. The Unix command "dmesg" should print
Wolfgang Denk16c8d5e2006-06-14 17:45:53 +0200655 it has found a new device. The environment variable usbtty
656 can be set to gserial or cdc_acm to enable your device to
Wolfgang Denk386eda02006-06-14 18:14:56 +0200657 appear to a USB host as a Linux gserial device or a
Wolfgang Denk16c8d5e2006-06-14 17:45:53 +0200658 Common Device Class Abstract Control Model serial device.
659 If you select usbtty = gserial you should be able to enumerate
660 a Linux host by
661 # modprobe usbserial vendor=0xVendorID product=0xProductID
662 else if using cdc_acm, simply setting the environment
663 variable usbtty to be cdc_acm should suffice. The following
664 might be defined in YourBoardName.h
Wolfgang Denk386eda02006-06-14 18:14:56 +0200665
Wolfgang Denk16c8d5e2006-06-14 17:45:53 +0200666 CONFIG_USB_DEVICE
667 Define this to build a UDC device
wdenkc6097192002-11-03 00:24:07 +0000668
Wolfgang Denk16c8d5e2006-06-14 17:45:53 +0200669 CONFIG_USB_TTY
670 Define this to have a tty type of device available to
671 talk to the UDC device
Wolfgang Denk386eda02006-06-14 18:14:56 +0200672
Vipin KUMARf9da0f82012-03-26 15:38:06 +0530673 CONFIG_USBD_HS
674 Define this to enable the high speed support for usb
675 device and usbtty. If this feature is enabled, a routine
676 int is_usbd_high_speed(void)
677 also needs to be defined by the driver to dynamically poll
678 whether the enumeration has succeded at high speed or full
679 speed.
680
Wolfgang Denk386eda02006-06-14 18:14:56 +0200681 If you have a USB-IF assigned VendorID then you may wish to
Wolfgang Denk16c8d5e2006-06-14 17:45:53 +0200682 define your own vendor specific values either in BoardName.h
Wolfgang Denk386eda02006-06-14 18:14:56 +0200683 or directly in usbd_vendor_info.h. If you don't define
Wolfgang Denk16c8d5e2006-06-14 17:45:53 +0200684 CONFIG_USBD_MANUFACTURER, CONFIG_USBD_PRODUCT_NAME,
685 CONFIG_USBD_VENDORID and CONFIG_USBD_PRODUCTID, then U-Boot
686 should pretend to be a Linux device to it's target host.
687
688 CONFIG_USBD_MANUFACTURER
689 Define this string as the name of your company for
690 - CONFIG_USBD_MANUFACTURER "my company"
Wolfgang Denk386eda02006-06-14 18:14:56 +0200691
Wolfgang Denk16c8d5e2006-06-14 17:45:53 +0200692 CONFIG_USBD_PRODUCT_NAME
693 Define this string as the name of your product
694 - CONFIG_USBD_PRODUCT_NAME "acme usb device"
695
696 CONFIG_USBD_VENDORID
697 Define this as your assigned Vendor ID from the USB
698 Implementors Forum. This *must* be a genuine Vendor ID
699 to avoid polluting the USB namespace.
700 - CONFIG_USBD_VENDORID 0xFFFF
Wolfgang Denk386eda02006-06-14 18:14:56 +0200701
Wolfgang Denk16c8d5e2006-06-14 17:45:53 +0200702 CONFIG_USBD_PRODUCTID
703 Define this as the unique Product ID
704 for your device
705 - CONFIG_USBD_PRODUCTID 0xFFFF
wdenkc6097192002-11-03 00:24:07 +0000706
Igor Grinbergd70a5602011-12-12 12:08:35 +0200707- ULPI Layer Support:
708 The ULPI (UTMI Low Pin (count) Interface) PHYs are supported via
709 the generic ULPI layer. The generic layer accesses the ULPI PHY
710 via the platform viewport, so you need both the genric layer and
711 the viewport enabled. Currently only Chipidea/ARC based
712 viewport is supported.
713 To enable the ULPI layer support, define CONFIG_USB_ULPI and
714 CONFIG_USB_ULPI_VIEWPORT in your board configuration file.
Lucas Stach6d365ea2012-10-01 00:44:35 +0200715 If your ULPI phy needs a different reference clock than the
716 standard 24 MHz then you have to define CONFIG_ULPI_REF_CLK to
717 the appropriate value in Hz.
wdenkc6097192002-11-03 00:24:07 +0000718
719- MMC Support:
Yoshihiro Shimodaafb35662011-07-04 22:21:22 +0000720 CONFIG_SH_MMCIF
721 Support for Renesas on-chip MMCIF controller
722
723 CONFIG_SH_MMCIF_ADDR
724 Define the base address of MMCIF registers
725
726 CONFIG_SH_MMCIF_CLK
727 Define the clock frequency for MMCIF
728
Tom Rinib3ba6e92013-03-14 05:32:47 +0000729- USB Device Firmware Update (DFU) class support:
Marek Vasutbb4059a2018-02-16 16:41:18 +0100730 CONFIG_DFU_OVER_USB
Tom Rinib3ba6e92013-03-14 05:32:47 +0000731 This enables the USB portion of the DFU USB class
732
Pantelis Antoniouc6631762013-03-14 05:32:52 +0000733 CONFIG_DFU_NAND
734 This enables support for exposing NAND devices via DFU.
735
Afzal Mohammeda9479f02013-09-18 01:15:24 +0530736 CONFIG_DFU_RAM
737 This enables support for exposing RAM via DFU.
738 Note: DFU spec refer to non-volatile memory usage, but
739 allow usages beyond the scope of spec - here RAM usage,
740 one that would help mostly the developer.
741
Heiko Schochere7e75c72013-06-12 06:05:51 +0200742 CONFIG_SYS_DFU_DATA_BUF_SIZE
743 Dfu transfer uses a buffer before writing data to the
744 raw storage device. Make the size (in bytes) of this buffer
745 configurable. The size of this buffer is also configurable
746 through the "dfu_bufsiz" environment variable.
747
Pantelis Antoniouea2453d2013-03-14 05:32:48 +0000748 CONFIG_SYS_DFU_MAX_FILE_SIZE
749 When updating files rather than the raw storage device,
750 we use a static buffer to copy the file into and then write
751 the buffer once we've been given the whole file. Define
752 this to the maximum filesize (in bytes) for the buffer.
753 Default is 4 MiB if undefined.
754
Heiko Schocher001a8312014-03-18 08:09:56 +0100755 DFU_DEFAULT_POLL_TIMEOUT
756 Poll timeout [ms], is the timeout a device can send to the
757 host. The host must wait for this timeout before sending
758 a subsequent DFU_GET_STATUS request to the device.
759
760 DFU_MANIFEST_POLL_TIMEOUT
761 Poll timeout [ms], which the device sends to the host when
762 entering dfuMANIFEST state. Host waits this timeout, before
763 sending again an USB request to the device.
764
wdenk6705d812004-08-02 23:22:59 +0000765- Journaling Flash filesystem support:
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +0200766 CONFIG_SYS_JFFS2_FIRST_SECTOR,
767 CONFIG_SYS_JFFS2_FIRST_BANK, CONFIG_SYS_JFFS2_NUM_BANKS
wdenk6705d812004-08-02 23:22:59 +0000768 Define these for a default partition on a NOR device
769
wdenkc6097192002-11-03 00:24:07 +0000770- Keyboard Support:
Simon Glass39f615e2015-11-11 10:05:47 -0700771 See Kconfig help for available keyboard drivers.
772
wdenkc6097192002-11-03 00:24:07 +0000773- LCD Support: CONFIG_LCD
774
775 Define this to enable LCD support (for output to LCD
776 display); also select one of the supported displays
777 by defining one of these:
778
wdenkfd3103b2003-11-25 16:55:19 +0000779 CONFIG_NEC_NL6448AC33:
wdenkc6097192002-11-03 00:24:07 +0000780
wdenkfd3103b2003-11-25 16:55:19 +0000781 NEC NL6448AC33-18. Active, color, single scan.
wdenkc6097192002-11-03 00:24:07 +0000782
wdenkfd3103b2003-11-25 16:55:19 +0000783 CONFIG_NEC_NL6448BC20
wdenkc6097192002-11-03 00:24:07 +0000784
wdenkfd3103b2003-11-25 16:55:19 +0000785 NEC NL6448BC20-08. 6.5", 640x480.
786 Active, color, single scan.
787
788 CONFIG_NEC_NL6448BC33_54
789
790 NEC NL6448BC33-54. 10.4", 640x480.
wdenkc6097192002-11-03 00:24:07 +0000791 Active, color, single scan.
792
793 CONFIG_SHARP_16x9
794
795 Sharp 320x240. Active, color, single scan.
796 It isn't 16x9, and I am not sure what it is.
797
798 CONFIG_SHARP_LQ64D341
799
800 Sharp LQ64D341 display, 640x480.
801 Active, color, single scan.
802
803 CONFIG_HLD1045
804
805 HLD1045 display, 640x480.
806 Active, color, single scan.
807
808 CONFIG_OPTREX_BW
809
810 Optrex CBL50840-2 NF-FW 99 22 M5
811 or
812 Hitachi LMG6912RPFC-00T
813 or
814 Hitachi SP14Q002
815
816 320x240. Black & white.
817
Simon Glass676d3192012-10-17 13:24:54 +0000818 CONFIG_LCD_ALIGNMENT
819
Jeremiah Mahlerb445bbb2015-01-04 18:56:50 -0800820 Normally the LCD is page-aligned (typically 4KB). If this is
Simon Glass676d3192012-10-17 13:24:54 +0000821 defined then the LCD will be aligned to this value instead.
822 For ARM it is sometimes useful to use MMU_SECTION_SIZE
823 here, since it is cheaper to change data cache settings on
824 a per-section basis.
825
826
Hannes Petermaier604c7d42015-03-27 08:01:38 +0100827 CONFIG_LCD_ROTATION
828
829 Sometimes, for example if the display is mounted in portrait
830 mode or even if it's mounted landscape but rotated by 180degree,
831 we need to rotate our content of the display relative to the
832 framebuffer, so that user can read the messages which are
833 printed out.
834 Once CONFIG_LCD_ROTATION is defined, the lcd_console will be
835 initialized with a given rotation from "vl_rot" out of
836 "vidinfo_t" which is provided by the board specific code.
837 The value for vl_rot is coded as following (matching to
838 fbcon=rotate:<n> linux-kernel commandline):
839 0 = no rotation respectively 0 degree
840 1 = 90 degree rotation
841 2 = 180 degree rotation
842 3 = 270 degree rotation
843
844 If CONFIG_LCD_ROTATION is not defined, the console will be
845 initialized with 0degree rotation.
846
wdenk17ea1172004-06-06 21:51:03 +0000847- MII/PHY support:
wdenk17ea1172004-06-06 21:51:03 +0000848 CONFIG_PHY_CLOCK_FREQ (ppc4xx)
849
850 The clock frequency of the MII bus
851
wdenk17ea1172004-06-06 21:51:03 +0000852 CONFIG_PHY_CMD_DELAY (ppc4xx)
853
854 Some PHY like Intel LXT971A need extra delay after
855 command issued before MII status register can be read
856
wdenkc6097192002-11-03 00:24:07 +0000857- IP address:
858 CONFIG_IPADDR
859
860 Define a default value for the IP address to use for
Marcel Ziswiler11ccc332008-07-09 08:17:15 +0200861 the default Ethernet interface, in case this is not
wdenkc6097192002-11-03 00:24:07 +0000862 determined through e.g. bootp.
Wolfgang Denk1ebcd652011-10-26 10:21:22 +0000863 (Environment variable "ipaddr")
wdenkc6097192002-11-03 00:24:07 +0000864
865- Server IP address:
866 CONFIG_SERVERIP
867
Marcel Ziswiler11ccc332008-07-09 08:17:15 +0200868 Defines a default value for the IP address of a TFTP
wdenkc6097192002-11-03 00:24:07 +0000869 server to contact when using the "tftboot" command.
Wolfgang Denk1ebcd652011-10-26 10:21:22 +0000870 (Environment variable "serverip")
wdenkc6097192002-11-03 00:24:07 +0000871
Wolfgang Denk1ebcd652011-10-26 10:21:22 +0000872- Gateway IP address:
873 CONFIG_GATEWAYIP
874
875 Defines a default value for the IP address of the
876 default router where packets to other networks are
877 sent to.
878 (Environment variable "gatewayip")
879
880- Subnet mask:
881 CONFIG_NETMASK
882
883 Defines a default value for the subnet mask (or
884 routing prefix) which is used to determine if an IP
885 address belongs to the local subnet or needs to be
886 forwarded through a router.
887 (Environment variable "netmask")
888
wdenkc6097192002-11-03 00:24:07 +0000889- BOOTP Recovery Mode:
890 CONFIG_BOOTP_RANDOM_DELAY
891
892 If you have many targets in a network that try to
893 boot using BOOTP, you may want to avoid that all
894 systems send out BOOTP requests at precisely the same
895 moment (which would happen for instance at recovery
896 from a power failure, when all systems will try to
897 boot, thus flooding the BOOTP server. Defining
898 CONFIG_BOOTP_RANDOM_DELAY causes a random delay to be
899 inserted before sending out BOOTP requests. The
Wolfgang Denk6c33c782007-08-06 23:21:05 +0200900 following delays are inserted then:
wdenkc6097192002-11-03 00:24:07 +0000901
902 1st BOOTP request: delay 0 ... 1 sec
903 2nd BOOTP request: delay 0 ... 2 sec
904 3rd BOOTP request: delay 0 ... 4 sec
905 4th and following
906 BOOTP requests: delay 0 ... 8 sec
907
Thierry Reding92ac8ac2014-08-19 10:21:24 +0200908 CONFIG_BOOTP_ID_CACHE_SIZE
909
910 BOOTP packets are uniquely identified using a 32-bit ID. The
911 server will copy the ID from client requests to responses and
912 U-Boot will use this to determine if it is the destination of
913 an incoming response. Some servers will check that addresses
914 aren't in use before handing them out (usually using an ARP
915 ping) and therefore take up to a few hundred milliseconds to
916 respond. Network congestion may also influence the time it
917 takes for a response to make it back to the client. If that
918 time is too long, U-Boot will retransmit requests. In order
919 to allow earlier responses to still be accepted after these
920 retransmissions, U-Boot's BOOTP client keeps a small cache of
921 IDs. The CONFIG_BOOTP_ID_CACHE_SIZE controls the size of this
922 cache. The default is to keep IDs for up to four outstanding
923 requests. Increasing this will allow U-Boot to accept offers
924 from a BOOTP client in networks with unusually high latency.
925
stroesefe389a82003-08-28 14:17:32 +0000926- DHCP Advanced Options:
Joe Hershberger2c00e092012-05-23 07:59:19 +0000927
Joe Hershbergerd22c3382012-05-23 08:00:12 +0000928 - Link-local IP address negotiation:
929 Negotiate with other link-local clients on the local network
930 for an address that doesn't require explicit configuration.
931 This is especially useful if a DHCP server cannot be guaranteed
932 to exist in all environments that the device must operate.
933
934 See doc/README.link-local for more information.
935
Prabhakar Kushwaha24acb832017-11-23 16:51:32 +0530936 - MAC address from environment variables
937
938 FDT_SEQ_MACADDR_FROM_ENV
939
940 Fix-up device tree with MAC addresses fetched sequentially from
941 environment variables. This config work on assumption that
942 non-usable ethernet node of device-tree are either not present
943 or their status has been marked as "disabled".
944
wdenka3d991b2004-04-15 21:48:45 +0000945 - CDP Options:
wdenk6e592382004-04-18 17:39:38 +0000946 CONFIG_CDP_DEVICE_ID
wdenka3d991b2004-04-15 21:48:45 +0000947
948 The device id used in CDP trigger frames.
949
950 CONFIG_CDP_DEVICE_ID_PREFIX
951
952 A two character string which is prefixed to the MAC address
953 of the device.
954
955 CONFIG_CDP_PORT_ID
956
957 A printf format string which contains the ascii name of
958 the port. Normally is set to "eth%d" which sets
Marcel Ziswiler11ccc332008-07-09 08:17:15 +0200959 eth0 for the first Ethernet, eth1 for the second etc.
wdenka3d991b2004-04-15 21:48:45 +0000960
961 CONFIG_CDP_CAPABILITIES
962
963 A 32bit integer which indicates the device capabilities;
964 0x00000010 for a normal host which does not forwards.
965
966 CONFIG_CDP_VERSION
967
968 An ascii string containing the version of the software.
969
970 CONFIG_CDP_PLATFORM
971
972 An ascii string containing the name of the platform.
973
974 CONFIG_CDP_TRIGGER
975
976 A 32bit integer sent on the trigger.
977
978 CONFIG_CDP_POWER_CONSUMPTION
979
980 A 16bit integer containing the power consumption of the
981 device in .1 of milliwatts.
982
983 CONFIG_CDP_APPLIANCE_VLAN_TYPE
984
985 A byte containing the id of the VLAN.
986
Uri Mashiach79267ed2017-01-19 10:51:05 +0200987- Status LED: CONFIG_LED_STATUS
wdenkc6097192002-11-03 00:24:07 +0000988
989 Several configurations allow to display the current
990 status using a LED. For instance, the LED will blink
991 fast while running U-Boot code, stop blinking as
992 soon as a reply to a BOOTP request was received, and
993 start blinking slow once the Linux kernel is running
994 (supported by a status LED driver in the Linux
Uri Mashiach79267ed2017-01-19 10:51:05 +0200995 kernel). Defining CONFIG_LED_STATUS enables this
wdenkc6097192002-11-03 00:24:07 +0000996 feature in U-Boot.
997
Igor Grinberg1df7bbb2013-11-08 01:03:50 +0200998 Additional options:
999
Uri Mashiach79267ed2017-01-19 10:51:05 +02001000 CONFIG_LED_STATUS_GPIO
Igor Grinberg1df7bbb2013-11-08 01:03:50 +02001001 The status LED can be connected to a GPIO pin.
1002 In such cases, the gpio_led driver can be used as a
Uri Mashiach79267ed2017-01-19 10:51:05 +02001003 status LED backend implementation. Define CONFIG_LED_STATUS_GPIO
Igor Grinberg1df7bbb2013-11-08 01:03:50 +02001004 to include the gpio_led driver in the U-Boot binary.
1005
Igor Grinberg9dfdcdf2013-11-08 01:03:52 +02001006 CONFIG_GPIO_LED_INVERTED_TABLE
1007 Some GPIO connected LEDs may have inverted polarity in which
1008 case the GPIO high value corresponds to LED off state and
1009 GPIO low value corresponds to LED on state.
1010 In such cases CONFIG_GPIO_LED_INVERTED_TABLE may be defined
1011 with a list of GPIO LEDs that have inverted polarity.
1012
Tom Rini55dabcc2021-08-18 23:12:24 -04001013- I2C Support:
Heiko Schocher3f4978c2012-01-16 21:12:24 +00001014 CONFIG_SYS_NUM_I2C_BUSES
Simon Glass945a18e2016-10-02 18:01:05 -06001015 Hold the number of i2c buses you want to use.
Heiko Schocher3f4978c2012-01-16 21:12:24 +00001016
1017 CONFIG_SYS_I2C_DIRECT_BUS
1018 define this, if you don't use i2c muxes on your hardware.
1019 if CONFIG_SYS_I2C_MAX_HOPS is not defined or == 0 you can
1020 omit this define.
1021
1022 CONFIG_SYS_I2C_MAX_HOPS
1023 define how many muxes are maximal consecutively connected
1024 on one i2c bus. If you not use i2c muxes, omit this
1025 define.
1026
1027 CONFIG_SYS_I2C_BUSES
Jeremiah Mahlerb445bbb2015-01-04 18:56:50 -08001028 hold a list of buses you want to use, only used if
Heiko Schocher3f4978c2012-01-16 21:12:24 +00001029 CONFIG_SYS_I2C_DIRECT_BUS is not defined, for example
1030 a board with CONFIG_SYS_I2C_MAX_HOPS = 1 and
1031 CONFIG_SYS_NUM_I2C_BUSES = 9:
1032
1033 CONFIG_SYS_I2C_BUSES {{0, {I2C_NULL_HOP}}, \
1034 {0, {{I2C_MUX_PCA9547, 0x70, 1}}}, \
1035 {0, {{I2C_MUX_PCA9547, 0x70, 2}}}, \
1036 {0, {{I2C_MUX_PCA9547, 0x70, 3}}}, \
1037 {0, {{I2C_MUX_PCA9547, 0x70, 4}}}, \
1038 {0, {{I2C_MUX_PCA9547, 0x70, 5}}}, \
1039 {1, {I2C_NULL_HOP}}, \
1040 {1, {{I2C_MUX_PCA9544, 0x72, 1}}}, \
1041 {1, {{I2C_MUX_PCA9544, 0x72, 2}}}, \
1042 }
1043
1044 which defines
1045 bus 0 on adapter 0 without a mux
Heiko Schocherea818db2013-01-29 08:53:15 +01001046 bus 1 on adapter 0 with a PCA9547 on address 0x70 port 1
1047 bus 2 on adapter 0 with a PCA9547 on address 0x70 port 2
1048 bus 3 on adapter 0 with a PCA9547 on address 0x70 port 3
1049 bus 4 on adapter 0 with a PCA9547 on address 0x70 port 4
1050 bus 5 on adapter 0 with a PCA9547 on address 0x70 port 5
Heiko Schocher3f4978c2012-01-16 21:12:24 +00001051 bus 6 on adapter 1 without a mux
Heiko Schocherea818db2013-01-29 08:53:15 +01001052 bus 7 on adapter 1 with a PCA9544 on address 0x72 port 1
1053 bus 8 on adapter 1 with a PCA9544 on address 0x72 port 2
Heiko Schocher3f4978c2012-01-16 21:12:24 +00001054
1055 If you do not have i2c muxes on your board, omit this define.
1056
Simon Glassce3b5d62017-05-12 21:10:00 -06001057- Legacy I2C Support:
Heiko Schocherea818db2013-01-29 08:53:15 +01001058 If you use the software i2c interface (CONFIG_SYS_I2C_SOFT)
wdenkb37c7e52003-06-30 16:24:52 +00001059 then the following macros need to be defined (examples are
1060 from include/configs/lwmon.h):
wdenkc6097192002-11-03 00:24:07 +00001061
1062 I2C_INIT
1063
wdenkb37c7e52003-06-30 16:24:52 +00001064 (Optional). Any commands necessary to enable the I2C
wdenk43d96162003-03-06 00:02:04 +00001065 controller or configure ports.
wdenkc6097192002-11-03 00:24:07 +00001066
wdenkba56f622004-02-06 23:19:44 +00001067 eg: #define I2C_INIT (immr->im_cpm.cp_pbdir |= PB_SCL)
wdenkb37c7e52003-06-30 16:24:52 +00001068
wdenkc6097192002-11-03 00:24:07 +00001069 I2C_ACTIVE
1070
1071 The code necessary to make the I2C data line active
1072 (driven). If the data line is open collector, this
1073 define can be null.
1074
wdenkb37c7e52003-06-30 16:24:52 +00001075 eg: #define I2C_ACTIVE (immr->im_cpm.cp_pbdir |= PB_SDA)
1076
wdenkc6097192002-11-03 00:24:07 +00001077 I2C_TRISTATE
1078
1079 The code necessary to make the I2C data line tri-stated
1080 (inactive). If the data line is open collector, this
1081 define can be null.
1082
wdenkb37c7e52003-06-30 16:24:52 +00001083 eg: #define I2C_TRISTATE (immr->im_cpm.cp_pbdir &= ~PB_SDA)
1084
wdenkc6097192002-11-03 00:24:07 +00001085 I2C_READ
1086
York Sun472d5462013-04-01 11:29:11 -07001087 Code that returns true if the I2C data line is high,
1088 false if it is low.
wdenkc6097192002-11-03 00:24:07 +00001089
wdenkb37c7e52003-06-30 16:24:52 +00001090 eg: #define I2C_READ ((immr->im_cpm.cp_pbdat & PB_SDA) != 0)
1091
wdenkc6097192002-11-03 00:24:07 +00001092 I2C_SDA(bit)
1093
York Sun472d5462013-04-01 11:29:11 -07001094 If <bit> is true, sets the I2C data line high. If it
1095 is false, it clears it (low).
wdenkc6097192002-11-03 00:24:07 +00001096
wdenkb37c7e52003-06-30 16:24:52 +00001097 eg: #define I2C_SDA(bit) \
wdenk2535d602003-07-17 23:16:40 +00001098 if(bit) immr->im_cpm.cp_pbdat |= PB_SDA; \
wdenkba56f622004-02-06 23:19:44 +00001099 else immr->im_cpm.cp_pbdat &= ~PB_SDA
wdenkb37c7e52003-06-30 16:24:52 +00001100
wdenkc6097192002-11-03 00:24:07 +00001101 I2C_SCL(bit)
1102
York Sun472d5462013-04-01 11:29:11 -07001103 If <bit> is true, sets the I2C clock line high. If it
1104 is false, it clears it (low).
wdenkc6097192002-11-03 00:24:07 +00001105
wdenkb37c7e52003-06-30 16:24:52 +00001106 eg: #define I2C_SCL(bit) \
wdenk2535d602003-07-17 23:16:40 +00001107 if(bit) immr->im_cpm.cp_pbdat |= PB_SCL; \
wdenkba56f622004-02-06 23:19:44 +00001108 else immr->im_cpm.cp_pbdat &= ~PB_SCL
wdenkb37c7e52003-06-30 16:24:52 +00001109
wdenkc6097192002-11-03 00:24:07 +00001110 I2C_DELAY
1111
1112 This delay is invoked four times per clock cycle so this
1113 controls the rate of data transfer. The data rate thus
wdenkb37c7e52003-06-30 16:24:52 +00001114 is 1 / (I2C_DELAY * 4). Often defined to be something
wdenk945af8d2003-07-16 21:53:01 +00001115 like:
1116
wdenkb37c7e52003-06-30 16:24:52 +00001117 #define I2C_DELAY udelay(2)
wdenkc6097192002-11-03 00:24:07 +00001118
Mike Frysinger793b5722010-07-21 13:38:02 -04001119 CONFIG_SOFT_I2C_GPIO_SCL / CONFIG_SOFT_I2C_GPIO_SDA
1120
1121 If your arch supports the generic GPIO framework (asm/gpio.h),
1122 then you may alternatively define the two GPIOs that are to be
1123 used as SCL / SDA. Any of the previous I2C_xxx macros will
1124 have GPIO-based defaults assigned to them as appropriate.
1125
1126 You should define these to the GPIO value as given directly to
1127 the generic GPIO functions.
1128
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02001129 CONFIG_SYS_I2C_INIT_BOARD
wdenk47cd00f2003-03-06 13:39:27 +00001130
wdenk8bde7f72003-06-27 21:31:46 +00001131 When a board is reset during an i2c bus transfer
1132 chips might think that the current transfer is still
1133 in progress. On some boards it is possible to access
1134 the i2c SCLK line directly, either by using the
1135 processor pin as a GPIO or by having a second pin
1136 connected to the bus. If this option is defined a
1137 custom i2c_init_board() routine in boards/xxx/board.c
1138 is run early in the boot sequence.
wdenk47cd00f2003-03-06 13:39:27 +00001139
Ben Warrenbb99ad62006-09-07 16:50:54 -04001140 CONFIG_I2C_MULTI_BUS
1141
1142 This option allows the use of multiple I2C buses, each of which
Wolfgang Denkc0f40852011-10-26 10:21:21 +00001143 must have a controller. At any point in time, only one bus is
1144 active. To switch to a different bus, use the 'i2c dev' command.
Ben Warrenbb99ad62006-09-07 16:50:54 -04001145 Note that bus numbering is zero-based.
1146
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02001147 CONFIG_SYS_I2C_NOPROBES
Ben Warrenbb99ad62006-09-07 16:50:54 -04001148
1149 This option specifies a list of I2C devices that will be skipped
Wolfgang Denkc0f40852011-10-26 10:21:21 +00001150 when the 'i2c probe' command is issued. If CONFIG_I2C_MULTI_BUS
Peter Tyser0f89c542009-04-18 22:34:03 -05001151 is set, specify a list of bus-device pairs. Otherwise, specify
1152 a 1D array of device addresses
Ben Warrenbb99ad62006-09-07 16:50:54 -04001153
1154 e.g.
1155 #undef CONFIG_I2C_MULTI_BUS
Wolfgang Denkc0f40852011-10-26 10:21:21 +00001156 #define CONFIG_SYS_I2C_NOPROBES {0x50,0x68}
Ben Warrenbb99ad62006-09-07 16:50:54 -04001157
1158 will skip addresses 0x50 and 0x68 on a board with one I2C bus
1159
Wolfgang Denkc0f40852011-10-26 10:21:21 +00001160 #define CONFIG_I2C_MULTI_BUS
Simon Glass945a18e2016-10-02 18:01:05 -06001161 #define CONFIG_SYS_I2C_NOPROBES {{0,0x50},{0,0x68},{1,0x54}}
Ben Warrenbb99ad62006-09-07 16:50:54 -04001162
1163 will skip addresses 0x50 and 0x68 on bus 0 and address 0x54 on bus 1
1164
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02001165 CONFIG_SYS_RTC_BUS_NUM
Stefan Roese0dc018e2007-02-20 10:51:26 +01001166
1167 If defined, then this indicates the I2C bus number for the RTC.
1168 If not defined, then U-Boot assumes that RTC is on I2C bus 0.
1169
Andrew Dyer2ac69852008-12-29 17:36:01 -06001170 CONFIG_SOFT_I2C_READ_REPEATED_START
1171
1172 defining this will force the i2c_read() function in
1173 the soft_i2c driver to perform an I2C repeated start
1174 between writing the address pointer and reading the
1175 data. If this define is omitted the default behaviour
1176 of doing a stop-start sequence will be used. Most I2C
1177 devices can use either method, but some require one or
1178 the other.
Timur Tabibe5e6182006-11-03 19:15:00 -06001179
wdenkc6097192002-11-03 00:24:07 +00001180- SPI Support: CONFIG_SPI
1181
1182 Enables SPI driver (so far only tested with
1183 SPI EEPROM, also an instance works with Crystal A/D and
1184 D/As on the SACSng board)
1185
Heiko Schocherf659b572014-07-14 10:22:11 +02001186 CONFIG_SYS_SPI_MXC_WAIT
1187 Timeout for waiting until spi transfer completed.
1188 default: (CONFIG_SYS_HZ/100) /* 10 ms */
1189
Matthias Fuchs01335022007-12-27 17:12:34 +01001190- FPGA Support: CONFIG_FPGA
1191
1192 Enables FPGA subsystem.
1193
1194 CONFIG_FPGA_<vendor>
1195
1196 Enables support for specific chip vendors.
1197 (ALTERA, XILINX)
1198
1199 CONFIG_FPGA_<family>
1200
1201 Enables support for FPGA family.
1202 (SPARTAN2, SPARTAN3, VIRTEX2, CYCLONE2, ACEX1K, ACEX)
1203
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02001204 CONFIG_SYS_FPGA_CHECK_BUSY
wdenkc6097192002-11-03 00:24:07 +00001205
wdenk43d96162003-03-06 00:02:04 +00001206 Enable checks on FPGA configuration interface busy
1207 status by the configuration function. This option
1208 will require a board or device specific function to
1209 be written.
wdenkc6097192002-11-03 00:24:07 +00001210
1211 CONFIG_FPGA_DELAY
1212
1213 If defined, a function that provides delays in the FPGA
1214 configuration driver.
1215
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02001216 CONFIG_SYS_FPGA_CHECK_ERROR
wdenkc6097192002-11-03 00:24:07 +00001217
wdenk43d96162003-03-06 00:02:04 +00001218 Check for configuration errors during FPGA bitfile
1219 loading. For example, abort during Virtex II
1220 configuration if the INIT_B line goes low (which
1221 indicated a CRC error).
wdenkc6097192002-11-03 00:24:07 +00001222
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02001223 CONFIG_SYS_FPGA_WAIT_INIT
wdenkc6097192002-11-03 00:24:07 +00001224
Jeremiah Mahlerb445bbb2015-01-04 18:56:50 -08001225 Maximum time to wait for the INIT_B line to de-assert
1226 after PROB_B has been de-asserted during a Virtex II
wdenk43d96162003-03-06 00:02:04 +00001227 FPGA configuration sequence. The default time is 500
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02001228 ms.
wdenkc6097192002-11-03 00:24:07 +00001229
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02001230 CONFIG_SYS_FPGA_WAIT_BUSY
wdenkc6097192002-11-03 00:24:07 +00001231
Jeremiah Mahlerb445bbb2015-01-04 18:56:50 -08001232 Maximum time to wait for BUSY to de-assert during
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02001233 Virtex II FPGA configuration. The default is 5 ms.
wdenkc6097192002-11-03 00:24:07 +00001234
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02001235 CONFIG_SYS_FPGA_WAIT_CONFIG
wdenkc6097192002-11-03 00:24:07 +00001236
wdenk43d96162003-03-06 00:02:04 +00001237 Time to wait after FPGA configuration. The default is
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02001238 200 ms.
wdenkc6097192002-11-03 00:24:07 +00001239
wdenkc6097192002-11-03 00:24:07 +00001240- Vendor Parameter Protection:
1241
wdenk43d96162003-03-06 00:02:04 +00001242 U-Boot considers the values of the environment
1243 variables "serial#" (Board Serial Number) and
wdenk7152b1d2003-09-05 23:19:14 +00001244 "ethaddr" (Ethernet Address) to be parameters that
wdenk43d96162003-03-06 00:02:04 +00001245 are set once by the board vendor / manufacturer, and
1246 protects these variables from casual modification by
1247 the user. Once set, these variables are read-only,
1248 and write or delete attempts are rejected. You can
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02001249 change this behaviour:
wdenkc6097192002-11-03 00:24:07 +00001250
1251 If CONFIG_ENV_OVERWRITE is #defined in your config
1252 file, the write protection for vendor parameters is
wdenk47cd00f2003-03-06 13:39:27 +00001253 completely disabled. Anybody can change or delete
wdenkc6097192002-11-03 00:24:07 +00001254 these parameters.
1255
Joe Hershberger92ac5202015-05-04 14:55:14 -05001256 Alternatively, if you define _both_ an ethaddr in the
1257 default env _and_ CONFIG_OVERWRITE_ETHADDR_ONCE, a default
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02001258 Ethernet address is installed in the environment,
wdenkc6097192002-11-03 00:24:07 +00001259 which can be changed exactly ONCE by the user. [The
1260 serial# is unaffected by this, i. e. it remains
1261 read-only.]
1262
Joe Hershberger25980902012-12-11 22:16:31 -06001263 The same can be accomplished in a more flexible way
1264 for any variable by configuring the type of access
1265 to allow for those variables in the ".flags" variable
1266 or define CONFIG_ENV_FLAGS_LIST_STATIC.
1267
wdenkc6097192002-11-03 00:24:07 +00001268- Protected RAM:
1269 CONFIG_PRAM
1270
1271 Define this variable to enable the reservation of
1272 "protected RAM", i. e. RAM which is not overwritten
1273 by U-Boot. Define CONFIG_PRAM to hold the number of
1274 kB you want to reserve for pRAM. You can overwrite
1275 this default value by defining an environment
1276 variable "pram" to the number of kB you want to
1277 reserve. Note that the board info structure will
1278 still show the full amount of RAM. If pRAM is
1279 reserved, a new environment variable "mem" will
1280 automatically be defined to hold the amount of
1281 remaining RAM in a form that can be passed as boot
1282 argument to Linux, for instance like that:
1283
Wolfgang Denkfe126d82005-11-20 21:40:11 +01001284 setenv bootargs ... mem=\${mem}
wdenkc6097192002-11-03 00:24:07 +00001285 saveenv
1286
1287 This way you can tell Linux not to use this memory,
1288 either, which results in a memory region that will
1289 not be affected by reboots.
1290
1291 *WARNING* If your board configuration uses automatic
1292 detection of the RAM size, you must make sure that
1293 this memory test is non-destructive. So far, the
1294 following board configurations are known to be
1295 "pRAM-clean":
1296
Heiko Schocher5b8e76c2017-06-07 17:33:09 +02001297 IVMS8, IVML24, SPD8xx,
Wolfgang Denk1b0757e2012-10-24 02:36:15 +00001298 HERMES, IP860, RPXlite, LWMON,
Heiko Schocher2eb48ff2017-06-07 17:33:10 +02001299 FLAGADM
wdenkc6097192002-11-03 00:24:07 +00001300
1301- Error Recovery:
wdenkc6097192002-11-03 00:24:07 +00001302 Note:
1303
wdenk8bde7f72003-06-27 21:31:46 +00001304 In the current implementation, the local variables
1305 space and global environment variables space are
1306 separated. Local variables are those you define by
1307 simply typing `name=value'. To access a local
1308 variable later on, you have write `$name' or
1309 `${name}'; to execute the contents of a variable
1310 directly type `$name' at the command prompt.
wdenkc6097192002-11-03 00:24:07 +00001311
wdenk43d96162003-03-06 00:02:04 +00001312 Global environment variables are those you use
1313 setenv/printenv to work with. To run a command stored
1314 in such a variable, you need to use the run command,
1315 and you must not use the '$' sign to access them.
wdenkc6097192002-11-03 00:24:07 +00001316
1317 To store commands and special characters in a
1318 variable, please use double quotation marks
1319 surrounding the whole text of the variable, instead
1320 of the backslashes before semicolons and special
1321 symbols.
1322
wdenka8c7c702003-12-06 19:49:23 +00001323- Default Environment:
wdenkc6097192002-11-03 00:24:07 +00001324 CONFIG_EXTRA_ENV_SETTINGS
1325
wdenk43d96162003-03-06 00:02:04 +00001326 Define this to contain any number of null terminated
1327 strings (variable = value pairs) that will be part of
wdenk7152b1d2003-09-05 23:19:14 +00001328 the default environment compiled into the boot image.
wdenk2262cfe2002-11-18 00:14:45 +00001329
wdenk43d96162003-03-06 00:02:04 +00001330 For example, place something like this in your
1331 board's config file:
wdenkc6097192002-11-03 00:24:07 +00001332
1333 #define CONFIG_EXTRA_ENV_SETTINGS \
1334 "myvar1=value1\0" \
1335 "myvar2=value2\0"
1336
wdenk43d96162003-03-06 00:02:04 +00001337 Warning: This method is based on knowledge about the
1338 internal format how the environment is stored by the
1339 U-Boot code. This is NOT an official, exported
1340 interface! Although it is unlikely that this format
wdenk7152b1d2003-09-05 23:19:14 +00001341 will change soon, there is no guarantee either.
wdenkc6097192002-11-03 00:24:07 +00001342 You better know what you are doing here.
1343
wdenk43d96162003-03-06 00:02:04 +00001344 Note: overly (ab)use of the default environment is
1345 discouraged. Make sure to check other ways to preset
Wolfgang Denk74de7ae2009-04-01 23:34:12 +02001346 the environment like the "source" command or the
wdenk43d96162003-03-06 00:02:04 +00001347 boot command first.
wdenkc6097192002-11-03 00:24:07 +00001348
Simon Glass06fd8532012-11-30 13:01:17 +00001349 CONFIG_DELAY_ENVIRONMENT
1350
1351 Normally the environment is loaded when the board is
Jeremiah Mahlerb445bbb2015-01-04 18:56:50 -08001352 initialised so that it is available to U-Boot. This inhibits
Simon Glass06fd8532012-11-30 13:01:17 +00001353 that so that the environment is not available until
1354 explicitly loaded later by U-Boot code. With CONFIG_OF_CONTROL
1355 this is instead controlled by the value of
1356 /config/load-environment.
1357
Wolfgang Denk4cf26092011-10-07 09:58:21 +02001358 CONFIG_STANDALONE_LOAD_ADDR
1359
Wolfgang Denk6feff892011-10-09 21:06:34 +02001360 This option defines a board specific value for the
1361 address where standalone program gets loaded, thus
1362 overwriting the architecture dependent default
Wolfgang Denk4cf26092011-10-07 09:58:21 +02001363 settings.
1364
Detlev Zundelcccfc2a2009-12-01 17:16:19 +01001365- Automatic software updates via TFTP server
1366 CONFIG_UPDATE_TFTP
1367 CONFIG_UPDATE_TFTP_CNT_MAX
1368 CONFIG_UPDATE_TFTP_MSEC_MAX
1369
1370 These options enable and control the auto-update feature;
1371 for a more detailed description refer to doc/README.update.
1372
1373- MTD Support (mtdparts command, UBI support)
Heiko Schocherff94bc42014-06-24 10:10:04 +02001374 CONFIG_MTD_UBI_WL_THRESHOLD
1375 This parameter defines the maximum difference between the highest
1376 erase counter value and the lowest erase counter value of eraseblocks
1377 of UBI devices. When this threshold is exceeded, UBI starts performing
1378 wear leveling by means of moving data from eraseblock with low erase
1379 counter to eraseblocks with high erase counter.
1380
1381 The default value should be OK for SLC NAND flashes, NOR flashes and
1382 other flashes which have eraseblock life-cycle 100000 or more.
1383 However, in case of MLC NAND flashes which typically have eraseblock
1384 life-cycle less than 10000, the threshold should be lessened (e.g.,
1385 to 128 or 256, although it does not have to be power of 2).
1386
1387 default: 4096
Simon Glassc654b512014-10-23 18:58:54 -06001388
Heiko Schocherff94bc42014-06-24 10:10:04 +02001389 CONFIG_MTD_UBI_BEB_LIMIT
1390 This option specifies the maximum bad physical eraseblocks UBI
1391 expects on the MTD device (per 1024 eraseblocks). If the
1392 underlying flash does not admit of bad eraseblocks (e.g. NOR
1393 flash), this value is ignored.
1394
1395 NAND datasheets often specify the minimum and maximum NVM
1396 (Number of Valid Blocks) for the flashes' endurance lifetime.
1397 The maximum expected bad eraseblocks per 1024 eraseblocks
1398 then can be calculated as "1024 * (1 - MinNVB / MaxNVB)",
1399 which gives 20 for most NANDs (MaxNVB is basically the total
1400 count of eraseblocks on the chip).
1401
1402 To put it differently, if this value is 20, UBI will try to
1403 reserve about 1.9% of physical eraseblocks for bad blocks
1404 handling. And that will be 1.9% of eraseblocks on the entire
1405 NAND chip, not just the MTD partition UBI attaches. This means
1406 that if you have, say, a NAND flash chip admits maximum 40 bad
1407 eraseblocks, and it is split on two MTD partitions of the same
1408 size, UBI will reserve 40 eraseblocks when attaching a
1409 partition.
1410
1411 default: 20
1412
1413 CONFIG_MTD_UBI_FASTMAP
1414 Fastmap is a mechanism which allows attaching an UBI device
1415 in nearly constant time. Instead of scanning the whole MTD device it
1416 only has to locate a checkpoint (called fastmap) on the device.
1417 The on-flash fastmap contains all information needed to attach
1418 the device. Using fastmap makes only sense on large devices where
1419 attaching by scanning takes long. UBI will not automatically install
1420 a fastmap on old images, but you can set the UBI parameter
1421 CONFIG_MTD_UBI_FASTMAP_AUTOCONVERT to 1 if you want so. Please note
1422 that fastmap-enabled images are still usable with UBI implementations
1423 without fastmap support. On typical flash devices the whole fastmap
1424 fits into one PEB. UBI will reserve PEBs to hold two fastmaps.
1425
1426 CONFIG_MTD_UBI_FASTMAP_AUTOCONVERT
1427 Set this parameter to enable fastmap automatically on images
1428 without a fastmap.
1429 default: 0
1430
Heiko Schocher0195a7b2015-10-22 06:19:21 +02001431 CONFIG_MTD_UBI_FM_DEBUG
1432 Enable UBI fastmap debug
1433 default: 0
1434
Daniel Schwierzeck6a11cf42011-07-18 07:48:07 +00001435- SPL framework
Wolfgang Denk04e5ae72011-09-11 21:24:09 +02001436 CONFIG_SPL
1437 Enable building of SPL globally.
Daniel Schwierzeck6a11cf42011-07-18 07:48:07 +00001438
Albert ARIBAUD \(3ADEV\)8c80eb32015-03-31 11:40:50 +02001439 CONFIG_SPL_PANIC_ON_RAW_IMAGE
1440 When defined, SPL will panic() if the image it has
1441 loaded does not have a signature.
1442 Defining this is useful when code which loads images
1443 in SPL cannot guarantee that absolutely all read errors
1444 will be caught.
1445 An example is the LPC32XX MLC NAND driver, which will
1446 consider that a completely unreadable NAND block is bad,
1447 and thus should be skipped silently.
1448
Tom Rini861a86f2012-08-13 11:37:56 -07001449 CONFIG_SPL_DISPLAY_PRINT
1450 For ARM, enable an optional function to print more information
1451 about the running system.
1452
Scott Wood06f60ae2012-12-06 13:33:17 +00001453 CONFIG_SPL_MPC83XX_WAIT_FOR_NAND
1454 Set this for NAND SPL on PPC mpc83xx targets, so that
1455 start.S waits for the rest of the SPL to load before
1456 continuing (the hardware starts execution after just
1457 loading the first page rather than the full 4K).
1458
Thomas Gleixner6f4e7d32016-07-12 20:28:12 +02001459 CONFIG_SPL_UBI
1460 Support for a lightweight UBI (fastmap) scanner and
1461 loader
1462
Tom Rini95579792012-02-14 07:29:40 +00001463 CONFIG_SYS_NAND_5_ADDR_CYCLE, CONFIG_SYS_NAND_PAGE_COUNT,
1464 CONFIG_SYS_NAND_PAGE_SIZE, CONFIG_SYS_NAND_OOBSIZE,
1465 CONFIG_SYS_NAND_BLOCK_SIZE, CONFIG_SYS_NAND_BAD_BLOCK_POS,
1466 CONFIG_SYS_NAND_ECCPOS, CONFIG_SYS_NAND_ECCSIZE,
1467 CONFIG_SYS_NAND_ECCBYTES
1468 Defines the size and behavior of the NAND that SPL uses
Scott Wood7d4b7952012-09-21 18:35:27 -05001469 to read U-Boot
Tom Rini95579792012-02-14 07:29:40 +00001470
Scott Wood7d4b7952012-09-21 18:35:27 -05001471 CONFIG_SYS_NAND_U_BOOT_DST
1472 Location in memory to load U-Boot to
1473
1474 CONFIG_SYS_NAND_U_BOOT_SIZE
1475 Size of image to load
Tom Rini95579792012-02-14 07:29:40 +00001476
1477 CONFIG_SYS_NAND_U_BOOT_START
Scott Wood7d4b7952012-09-21 18:35:27 -05001478 Entry point in loaded image to jump to
Tom Rini95579792012-02-14 07:29:40 +00001479
1480 CONFIG_SYS_NAND_HW_ECC_OOBFIRST
1481 Define this if you need to first read the OOB and then the
Jeremiah Mahlerb445bbb2015-01-04 18:56:50 -08001482 data. This is used, for example, on davinci platforms.
Tom Rini95579792012-02-14 07:29:40 +00001483
Pavel Machekc57b9532012-08-30 22:42:11 +02001484 CONFIG_SPL_RAM_DEVICE
1485 Support for running image already present in ram, in SPL binary
1486
Marek Vasutb527b9c2018-05-13 00:22:52 +02001487 CONFIG_SPL_FIT_PRINT
Simon Glass87ebee32013-05-08 08:05:59 +00001488 Printing information about a FIT image adds quite a bit of
1489 code to SPL. So this is normally disabled in SPL. Use this
1490 option to re-enable it. This will affect the output of the
1491 bootm command when booting a FIT image.
1492
wdenka8c7c702003-12-06 19:49:23 +00001493- Interrupt support (PPC):
1494
wdenkd4ca31c2004-01-02 14:00:00 +00001495 There are common interrupt_init() and timer_interrupt()
1496 for all PPC archs. interrupt_init() calls interrupt_init_cpu()
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02001497 for CPU specific initialization. interrupt_init_cpu()
wdenkd4ca31c2004-01-02 14:00:00 +00001498 should set decrementer_count to appropriate value. If
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02001499 CPU resets decrementer automatically after interrupt
wdenkd4ca31c2004-01-02 14:00:00 +00001500 (ppc4xx) it should set decrementer_count to zero.
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02001501 timer_interrupt() calls timer_interrupt_cpu() for CPU
wdenkd4ca31c2004-01-02 14:00:00 +00001502 specific handling. If board has watchdog / status_led
1503 / other_activity_monitor it works automatically from
1504 general timer_interrupt().
wdenka8c7c702003-12-06 19:49:23 +00001505
wdenkc6097192002-11-03 00:24:07 +00001506
Helmut Raiger9660e442011-10-20 04:19:47 +00001507Board initialization settings:
1508------------------------------
1509
1510During Initialization u-boot calls a number of board specific functions
1511to allow the preparation of board specific prerequisites, e.g. pin setup
1512before drivers are initialized. To enable these callbacks the
1513following configuration macros have to be defined. Currently this is
1514architecture specific, so please check arch/your_architecture/lib/board.c
1515typically in board_init_f() and board_init_r().
1516
1517- CONFIG_BOARD_EARLY_INIT_F: Call board_early_init_f()
1518- CONFIG_BOARD_EARLY_INIT_R: Call board_early_init_r()
1519- CONFIG_BOARD_LATE_INIT: Call board_late_init()
wdenkc6097192002-11-03 00:24:07 +00001520
wdenkc6097192002-11-03 00:24:07 +00001521Configuration Settings:
1522-----------------------
1523
Simon Glass4d979bf2019-12-28 10:45:10 -07001524- MEM_SUPPORT_64BIT_DATA: Defined automatically if compiled as 64-bit.
York Sun4d1fd7f2014-02-26 17:03:19 -08001525 Optionally it can be defined to support 64-bit memory commands.
1526
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02001527- CONFIG_SYS_LONGHELP: Defined when you want long help messages included;
wdenkc6097192002-11-03 00:24:07 +00001528 undefine this when you're short of memory.
1529
Peter Tyser2fb26042009-01-27 18:03:12 -06001530- CONFIG_SYS_HELP_CMD_WIDTH: Defined when you want to override the default
1531 width of the commands listed in the 'help' command output.
1532
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02001533- CONFIG_SYS_PROMPT: This is what U-Boot prints on the console to
wdenkc6097192002-11-03 00:24:07 +00001534 prompt for user input.
1535
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02001536- CONFIG_SYS_BAUDRATE_TABLE:
wdenkc6097192002-11-03 00:24:07 +00001537 List of legal baudrate settings for this board.
1538
York Sune8149522015-12-04 11:57:07 -08001539- CONFIG_SYS_MEM_RESERVE_SECURE
York Sune61a7532016-06-24 16:46:18 -07001540 Only implemented for ARMv8 for now.
York Sune8149522015-12-04 11:57:07 -08001541 If defined, the size of CONFIG_SYS_MEM_RESERVE_SECURE memory
1542 is substracted from total RAM and won't be reported to OS.
1543 This memory can be used as secure memory. A variable
York Sune61a7532016-06-24 16:46:18 -07001544 gd->arch.secure_ram is used to track the location. In systems
York Sune8149522015-12-04 11:57:07 -08001545 the RAM base is not zero, or RAM is divided into banks,
1546 this variable needs to be recalcuated to get the address.
1547
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02001548- CONFIG_SYS_LOADS_BAUD_CHANGE:
wdenkc6097192002-11-03 00:24:07 +00001549 Enable temporary baudrate change while serial download
1550
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02001551- CONFIG_SYS_SDRAM_BASE:
wdenkc6097192002-11-03 00:24:07 +00001552 Physical start address of SDRAM. _Must_ be 0 here.
1553
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02001554- CONFIG_SYS_FLASH_BASE:
wdenkc6097192002-11-03 00:24:07 +00001555 Physical start address of Flash memory.
1556
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02001557- CONFIG_SYS_MONITOR_LEN:
wdenk8bde7f72003-06-27 21:31:46 +00001558 Size of memory reserved for monitor code, used to
1559 determine _at_compile_time_ (!) if the environment is
1560 embedded within the U-Boot image, or in a separate
1561 flash sector.
wdenkc6097192002-11-03 00:24:07 +00001562
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02001563- CONFIG_SYS_MALLOC_LEN:
wdenkc6097192002-11-03 00:24:07 +00001564 Size of DRAM reserved for malloc() use.
1565
Simon Glassd59476b2014-07-10 22:23:28 -06001566- CONFIG_SYS_MALLOC_F_LEN
1567 Size of the malloc() pool for use before relocation. If
1568 this is defined, then a very simple malloc() implementation
1569 will become available before relocation. The address is just
1570 below the global data, and the stack is moved down to make
1571 space.
1572
1573 This feature allocates regions with increasing addresses
1574 within the region. calloc() is supported, but realloc()
1575 is not available. free() is supported but does nothing.
Jeremiah Mahlerb445bbb2015-01-04 18:56:50 -08001576 The memory will be freed (or in fact just forgotten) when
Simon Glassd59476b2014-07-10 22:23:28 -06001577 U-Boot relocates itself.
1578
Simon Glass38687ae2014-11-10 17:16:54 -07001579- CONFIG_SYS_MALLOC_SIMPLE
1580 Provides a simple and small malloc() and calloc() for those
1581 boards which do not use the full malloc in SPL (which is
Tom Rini10f6e4d2022-05-27 12:48:32 -04001582 enabled with CONFIG_SYS_SPL_MALLOC).
Simon Glass38687ae2014-11-10 17:16:54 -07001583
Thierry Reding1dfdd9b2014-12-09 22:25:22 -07001584- CONFIG_SYS_NONCACHED_MEMORY:
1585 Size of non-cached memory area. This area of memory will be
1586 typically located right below the malloc() area and mapped
1587 uncached in the MMU. This is useful for drivers that would
1588 otherwise require a lot of explicit cache maintenance. For
1589 some drivers it's also impossible to properly maintain the
1590 cache. For example if the regions that need to be flushed
1591 are not a multiple of the cache-line size, *and* padding
1592 cannot be allocated between the regions to align them (i.e.
1593 if the HW requires a contiguous array of regions, and the
1594 size of each region is not cache-aligned), then a flush of
1595 one region may result in overwriting data that hardware has
1596 written to another region in the same cache-line. This can
1597 happen for example in network drivers where descriptors for
1598 buffers are typically smaller than the CPU cache-line (e.g.
1599 16 bytes vs. 32 or 64 bytes).
1600
1601 Non-cached memory is only supported on 32-bit ARM at present.
1602
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02001603- CONFIG_SYS_BOOTMAPSZ:
wdenkc6097192002-11-03 00:24:07 +00001604 Maximum size of memory mapped by the startup code of
1605 the Linux kernel; all data that must be processed by
Bartlomiej Sieka7d721e32008-04-14 15:44:16 +02001606 the Linux kernel (bd_info, boot arguments, FDT blob if
1607 used) must be put below this limit, unless "bootm_low"
Robert P. J. Day1bce2ae2013-09-16 07:15:45 -04001608 environment variable is defined and non-zero. In such case
Bartlomiej Sieka7d721e32008-04-14 15:44:16 +02001609 all data for the Linux kernel must be between "bootm_low"
Wolfgang Denkc0f40852011-10-26 10:21:21 +00001610 and "bootm_low" + CONFIG_SYS_BOOTMAPSZ. The environment
Grant Likelyc3624e62011-03-28 09:58:43 +00001611 variable "bootm_mapsize" will override the value of
1612 CONFIG_SYS_BOOTMAPSZ. If CONFIG_SYS_BOOTMAPSZ is undefined,
1613 then the value in "bootm_size" will be used instead.
wdenkc6097192002-11-03 00:24:07 +00001614
John Rigbyfca43cc2010-10-13 13:57:35 -06001615- CONFIG_SYS_BOOT_GET_CMDLINE:
1616 Enables allocating and saving kernel cmdline in space between
1617 "bootm_low" and "bootm_low" + BOOTMAPSZ.
1618
1619- CONFIG_SYS_BOOT_GET_KBD:
1620 Enables allocating and saving a kernel copy of the bd_info in
1621 space between "bootm_low" and "bootm_low" + BOOTMAPSZ.
1622
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02001623- CONFIG_SYS_FLASH_PROTECTION
wdenk8564acf2003-07-14 22:13:32 +00001624 If defined, hardware flash sectors protection is used
1625 instead of U-Boot software protection.
1626
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02001627- CONFIG_SYS_FLASH_CFI:
wdenk43d96162003-03-06 00:02:04 +00001628 Define if the flash driver uses extra elements in the
wdenk5653fc32004-02-08 22:55:38 +00001629 common flash structure for storing flash geometry.
1630
Jean-Christophe PLAGNIOL-VILLARD00b18832008-08-13 01:40:42 +02001631- CONFIG_FLASH_CFI_DRIVER
wdenk5653fc32004-02-08 22:55:38 +00001632 This option also enables the building of the cfi_flash driver
1633 in the drivers directory
wdenkc6097192002-11-03 00:24:07 +00001634
Piotr Ziecik91809ed2008-11-17 15:57:58 +01001635- CONFIG_FLASH_CFI_MTD
1636 This option enables the building of the cfi_mtd driver
1637 in the drivers directory. The driver exports CFI flash
1638 to the MTD layer.
1639
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02001640- CONFIG_SYS_FLASH_USE_BUFFER_WRITE
Guennadi Liakhovetski96ef8312008-04-03 13:36:02 +02001641 Use buffered writes to flash.
1642
1643- CONFIG_FLASH_SPANSION_S29WS_N
1644 s29ws-n MirrorBit flash has non-standard addresses for buffered
1645 write commands.
1646
Jerry Van Baren9a042e92008-03-08 13:48:01 -05001647- CONFIG_FLASH_SHOW_PROGRESS
1648 If defined (must be an integer), print out countdown
1649 digits and dots. Recommended value: 45 (9..1) for 80
1650 column displays, 15 (3..1) for 40 column displays.
1651
Stefan Roese352ef3f2013-04-04 15:53:14 +02001652- CONFIG_FLASH_VERIFY
1653 If defined, the content of the flash (destination) is compared
1654 against the source after the write operation. An error message
1655 will be printed when the contents are not identical.
1656 Please note that this option is useless in nearly all cases,
1657 since such flash programming errors usually are detected earlier
1658 while unprotecting/erasing/programming. Please only enable
1659 this option if you really know what you are doing.
1660
Joe Hershberger25980902012-12-11 22:16:31 -06001661- CONFIG_ENV_FLAGS_LIST_DEFAULT
1662- CONFIG_ENV_FLAGS_LIST_STATIC
Robert P. J. Day1bce2ae2013-09-16 07:15:45 -04001663 Enable validation of the values given to environment variables when
Joe Hershberger25980902012-12-11 22:16:31 -06001664 calling env set. Variables can be restricted to only decimal,
1665 hexadecimal, or boolean. If CONFIG_CMD_NET is also defined,
1666 the variables can also be restricted to IP address or MAC address.
1667
1668 The format of the list is:
1669 type_attribute = [s|d|x|b|i|m]
Jeremiah Mahlerb445bbb2015-01-04 18:56:50 -08001670 access_attribute = [a|r|o|c]
1671 attributes = type_attribute[access_attribute]
Joe Hershberger25980902012-12-11 22:16:31 -06001672 entry = variable_name[:attributes]
1673 list = entry[,list]
1674
1675 The type attributes are:
1676 s - String (default)
1677 d - Decimal
1678 x - Hexadecimal
1679 b - Boolean ([1yYtT|0nNfF])
1680 i - IP address
1681 m - MAC address
1682
Joe Hershberger267541f2012-12-11 22:16:34 -06001683 The access attributes are:
1684 a - Any (default)
1685 r - Read-only
1686 o - Write-once
1687 c - Change-default
1688
Joe Hershberger25980902012-12-11 22:16:31 -06001689 - CONFIG_ENV_FLAGS_LIST_DEFAULT
1690 Define this to a list (string) to define the ".flags"
Jeremiah Mahlerb445bbb2015-01-04 18:56:50 -08001691 environment variable in the default or embedded environment.
Joe Hershberger25980902012-12-11 22:16:31 -06001692
1693 - CONFIG_ENV_FLAGS_LIST_STATIC
1694 Define this to a list (string) to define validation that
1695 should be done if an entry is not found in the ".flags"
1696 environment variable. To override a setting in the static
1697 list, simply add an entry for the same variable name to the
1698 ".flags" variable.
1699
Joe Hershbergerbdf1fe42015-05-20 14:27:20 -05001700 If CONFIG_REGEX is defined, the variable_name above is evaluated as a
1701 regular expression. This allows multiple variables to define the same
1702 flags without explicitly listing them for each variable.
1703
wdenkc6097192002-11-03 00:24:07 +00001704The following definitions that deal with the placement and management
1705of environment data (variable area); in general, we support the
1706following configurations:
1707
Mike Frysingerc3eb3fe2011-07-08 10:44:25 +00001708- CONFIG_BUILD_ENVCRC:
1709
1710 Builds up envcrc with the target environment so that external utils
1711 may easily extract it and embed it in final U-Boot images.
1712
wdenkc6097192002-11-03 00:24:07 +00001713BE CAREFUL! The first access to the environment happens quite early
Jeremiah Mahlerb445bbb2015-01-04 18:56:50 -08001714in U-Boot initialization (when we try to get the setting of for the
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02001715console baudrate). You *MUST* have mapped your NVRAM area then, or
wdenkc6097192002-11-03 00:24:07 +00001716U-Boot will hang.
1717
1718Please note that even with NVRAM we still use a copy of the
1719environment in RAM: we could work on NVRAM directly, but we want to
1720keep settings there always unmodified except somebody uses "saveenv"
1721to save the current settings.
1722
Liu Gang0a85a9e2012-03-08 00:33:20 +00001723BE CAREFUL! For some special cases, the local device can not use
1724"saveenv" command. For example, the local device will get the
Liu Gangfc54c7f2012-08-09 05:10:01 +00001725environment stored in a remote NOR flash by SRIO or PCIE link,
1726but it can not erase, write this NOR flash by SRIO or PCIE interface.
Liu Gang0a85a9e2012-03-08 00:33:20 +00001727
Guennadi Liakhovetskib74ab732009-05-18 16:07:22 +02001728- CONFIG_NAND_ENV_DST
1729
1730 Defines address in RAM to which the nand_spl code should copy the
1731 environment. If redundant environment is used, it will be copied to
1732 CONFIG_NAND_ENV_DST + CONFIG_ENV_SIZE.
1733
Bruce Adlere881cb52007-11-02 13:15:42 -07001734Please note that the environment is read-only until the monitor
wdenkc6097192002-11-03 00:24:07 +00001735has been relocated to RAM and a RAM copy of the environment has been
Simon Glass00caae62017-08-03 12:22:12 -06001736created; also, when using EEPROM you will have to use env_get_f()
wdenkc6097192002-11-03 00:24:07 +00001737until then to read environment variables.
1738
wdenk85ec0bc2003-03-31 16:34:49 +00001739The environment is protected by a CRC32 checksum. Before the monitor
1740is relocated into RAM, as a result of a bad CRC you will be working
1741with the compiled-in default environment - *silently*!!! [This is
1742necessary, because the first environment variable we need is the
1743"baudrate" setting for the console - if we have a bad CRC, we don't
1744have any device yet where we could complain.]
wdenkc6097192002-11-03 00:24:07 +00001745
1746Note: once the monitor has been relocated, then it will complain if
1747the default environment is used; a new CRC is computed as soon as you
wdenk85ec0bc2003-03-31 16:34:49 +00001748use the "saveenv" command to store a valid environment.
wdenkc6097192002-11-03 00:24:07 +00001749
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02001750- CONFIG_SYS_FAULT_MII_ADDR:
wdenk42d1f032003-10-15 23:53:47 +00001751 MII address of the PHY to check for the Ethernet link state.
wdenkc6097192002-11-03 00:24:07 +00001752
Ron Madridf5675aa2009-02-18 14:30:44 -08001753- CONFIG_NS16550_MIN_FUNCTIONS:
1754 Define this if you desire to only have use of the NS16550_init
1755 and NS16550_putc functions for the serial driver located at
1756 drivers/serial/ns16550.c. This option is useful for saving
1757 space for already greatly restricted images, including but not
1758 limited to NAND_SPL configurations.
1759
Simon Glassb2b92f52012-11-30 13:01:18 +00001760- CONFIG_DISPLAY_BOARDINFO
1761 Display information about the board that U-Boot is running on
1762 when U-Boot starts up. The board function checkboard() is called
1763 to do this.
1764
Simon Glasse2e3e2b2012-11-30 13:01:19 +00001765- CONFIG_DISPLAY_BOARDINFO_LATE
1766 Similar to the previous option, but display this information
1767 later, once stdio is running and output goes to the LCD, if
1768 present.
1769
wdenkc6097192002-11-03 00:24:07 +00001770Low Level (hardware related) configuration options:
wdenkdc7c9a12003-03-26 06:55:25 +00001771---------------------------------------------------
wdenkc6097192002-11-03 00:24:07 +00001772
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02001773- CONFIG_SYS_CACHELINE_SIZE:
wdenkc6097192002-11-03 00:24:07 +00001774 Cache Line Size of the CPU.
1775
Timur Tabie46fedf2011-08-04 18:03:41 -05001776- CONFIG_SYS_CCSRBAR_DEFAULT:
1777 Default (power-on reset) physical address of CCSR on Freescale
1778 PowerPC SOCs.
1779
1780- CONFIG_SYS_CCSRBAR:
1781 Virtual address of CCSR. On a 32-bit build, this is typically
1782 the same value as CONFIG_SYS_CCSRBAR_DEFAULT.
1783
Timur Tabie46fedf2011-08-04 18:03:41 -05001784- CONFIG_SYS_CCSRBAR_PHYS:
1785 Physical address of CCSR. CCSR can be relocated to a new
1786 physical address, if desired. In this case, this macro should
Wolfgang Denkc0f40852011-10-26 10:21:21 +00001787 be set to that address. Otherwise, it should be set to the
Timur Tabie46fedf2011-08-04 18:03:41 -05001788 same value as CONFIG_SYS_CCSRBAR_DEFAULT. For example, CCSR
1789 is typically relocated on 36-bit builds. It is recommended
1790 that this macro be defined via the _HIGH and _LOW macros:
1791
1792 #define CONFIG_SYS_CCSRBAR_PHYS ((CONFIG_SYS_CCSRBAR_PHYS_HIGH
1793 * 1ull) << 32 | CONFIG_SYS_CCSRBAR_PHYS_LOW)
1794
1795- CONFIG_SYS_CCSRBAR_PHYS_HIGH:
Wolfgang Denk4cf26092011-10-07 09:58:21 +02001796 Bits 33-36 of CONFIG_SYS_CCSRBAR_PHYS. This value is typically
1797 either 0 (32-bit build) or 0xF (36-bit build). This macro is
Timur Tabie46fedf2011-08-04 18:03:41 -05001798 used in assembly code, so it must not contain typecasts or
1799 integer size suffixes (e.g. "ULL").
1800
1801- CONFIG_SYS_CCSRBAR_PHYS_LOW:
1802 Lower 32-bits of CONFIG_SYS_CCSRBAR_PHYS. This macro is
1803 used in assembly code, so it must not contain typecasts or
1804 integer size suffixes (e.g. "ULL").
1805
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02001806- CONFIG_SYS_IMMR: Physical address of the Internal Memory.
wdenkefe2a4d2004-12-16 21:44:03 +00001807 DO NOT CHANGE unless you know exactly what you're
Christophe Leroy907208c2017-07-06 10:23:22 +02001808 doing! (11-4) [MPC8xx systems only]
wdenkc6097192002-11-03 00:24:07 +00001809
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02001810- CONFIG_SYS_INIT_RAM_ADDR:
wdenkc6097192002-11-03 00:24:07 +00001811
wdenk7152b1d2003-09-05 23:19:14 +00001812 Start address of memory area that can be used for
wdenkc6097192002-11-03 00:24:07 +00001813 initial data and stack; please note that this must be
1814 writable memory that is working WITHOUT special
1815 initialization, i. e. you CANNOT use normal RAM which
1816 will become available only after programming the
1817 memory controller and running certain initialization
1818 sequences.
1819
1820 U-Boot uses the following memory types:
Christophe Leroy907208c2017-07-06 10:23:22 +02001821 - MPC8xx: IMMR (internal memory of the CPU)
wdenkc6097192002-11-03 00:24:07 +00001822
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02001823- CONFIG_SYS_SCCR: System Clock and reset Control Register (15-27)
wdenkc6097192002-11-03 00:24:07 +00001824
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02001825- CONFIG_SYS_OR_TIMING_SDRAM:
wdenkc6097192002-11-03 00:24:07 +00001826 SDRAM timing
1827
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02001828- CONFIG_SYS_MAMR_PTA:
wdenkc6097192002-11-03 00:24:07 +00001829 periodic timer for refresh
1830
Kumar Galaa09b9b62010-12-30 12:09:53 -06001831- CONFIG_SYS_SRIO:
1832 Chip has SRIO or not
1833
1834- CONFIG_SRIO1:
1835 Board has SRIO 1 port available
1836
1837- CONFIG_SRIO2:
1838 Board has SRIO 2 port available
1839
Liu Gangc8b28152013-05-07 16:30:46 +08001840- CONFIG_SRIO_PCIE_BOOT_MASTER
1841 Board can support master function for Boot from SRIO and PCIE
1842
Kumar Galaa09b9b62010-12-30 12:09:53 -06001843- CONFIG_SYS_SRIOn_MEM_VIRT:
1844 Virtual Address of SRIO port 'n' memory region
1845
Simon Glass62f9b652019-11-14 12:57:09 -07001846- CONFIG_SYS_SRIOn_MEM_PHYxS:
Kumar Galaa09b9b62010-12-30 12:09:53 -06001847 Physical Address of SRIO port 'n' memory region
1848
1849- CONFIG_SYS_SRIOn_MEM_SIZE:
1850 Size of SRIO port 'n' memory region
1851
Fabio Estevam66bd1842013-04-11 09:35:34 +00001852- CONFIG_SYS_NAND_BUSWIDTH_16BIT
1853 Defined to tell the NAND controller that the NAND chip is using
1854 a 16 bit bus.
1855 Not all NAND drivers use this symbol.
Fabio Estevama430e912013-04-11 09:35:35 +00001856 Example of drivers that use it:
Miquel Raynala430fa02018-08-16 17:30:07 +02001857 - drivers/mtd/nand/raw/ndfc.c
1858 - drivers/mtd/nand/raw/mxc_nand.c
Alex Watermaneced4622011-05-19 15:08:36 -04001859
1860- CONFIG_SYS_NDFC_EBC0_CFG
1861 Sets the EBC0_CFG register for the NDFC. If not defined
1862 a default value will be used.
1863
Ben Warrenbb99ad62006-09-07 16:50:54 -04001864- CONFIG_SPD_EEPROM
Wolfgang Denk218ca722008-03-26 10:40:12 +01001865 Get DDR timing information from an I2C EEPROM. Common
1866 with pluggable memory modules such as SODIMMs
1867
Ben Warrenbb99ad62006-09-07 16:50:54 -04001868 SPD_EEPROM_ADDRESS
1869 I2C address of the SPD EEPROM
1870
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02001871- CONFIG_SYS_SPD_BUS_NUM
Wolfgang Denk218ca722008-03-26 10:40:12 +01001872 If SPD EEPROM is on an I2C bus other than the first
1873 one, specify here. Note that the value must resolve
1874 to something your driver can deal with.
Ben Warrenbb99ad62006-09-07 16:50:54 -04001875
York Sun6f5e1dc2011-09-16 13:21:35 -07001876- CONFIG_FSL_DDR_INTERACTIVE
1877 Enable interactive DDR debugging. See doc/README.fsl-ddr.
1878
York Sune32d59a2015-01-06 13:18:55 -08001879- CONFIG_FSL_DDR_SYNC_REFRESH
1880 Enable sync of refresh for multiple controllers.
1881
York Sun4516ff82015-03-19 09:30:28 -07001882- CONFIG_FSL_DDR_BIST
1883 Enable built-in memory test for Freescale DDR controllers.
1884
wdenkc26e4542004-04-18 10:13:26 +00001885- CONFIG_RMII
1886 Enable RMII mode for all FECs.
1887 Note that this is a global option, we can't
1888 have one FEC in standard MII mode and another in RMII mode.
1889
wdenk5cf91d62004-04-23 20:32:05 +00001890- CONFIG_CRC32_VERIFY
1891 Add a verify option to the crc32 command.
1892 The syntax is:
1893
1894 => crc32 -v <address> <count> <crc32>
1895
1896 Where address/count indicate a memory area
1897 and crc32 is the correct crc32 which the
1898 area should have.
1899
wdenk56523f12004-07-11 17:40:54 +00001900- CONFIG_LOOPW
1901 Add the "loopw" memory command. This only takes effect if
Simon Glass493f4202017-08-04 16:34:27 -06001902 the memory commands are activated globally (CONFIG_CMD_MEMORY).
wdenk56523f12004-07-11 17:40:54 +00001903
Joel Johnson72732312020-01-29 09:17:18 -07001904- CONFIG_CMD_MX_CYCLIC
stroese7b466642004-12-16 18:46:55 +00001905 Add the "mdc" and "mwc" memory commands. These are cyclic
1906 "md/mw" commands.
1907 Examples:
1908
wdenkefe2a4d2004-12-16 21:44:03 +00001909 => mdc.b 10 4 500
stroese7b466642004-12-16 18:46:55 +00001910 This command will print 4 bytes (10,11,12,13) each 500 ms.
1911
wdenkefe2a4d2004-12-16 21:44:03 +00001912 => mwc.l 100 12345678 10
stroese7b466642004-12-16 18:46:55 +00001913 This command will write 12345678 to address 100 all 10 ms.
1914
wdenkefe2a4d2004-12-16 21:44:03 +00001915 This only takes effect if the memory commands are activated
Simon Glass493f4202017-08-04 16:34:27 -06001916 globally (CONFIG_CMD_MEMORY).
stroese7b466642004-12-16 18:46:55 +00001917
Aneesh V401bb302011-07-13 05:11:07 +00001918- CONFIG_SPL_BUILD
Thomas Hebb32f2ca22019-11-13 18:18:03 -08001919 Set when the currently-running compilation is for an artifact
1920 that will end up in the SPL (as opposed to the TPL or U-Boot
1921 proper). Code that needs stage-specific behavior should check
1922 this.
wdenk400558b2005-04-02 23:52:25 +00001923
Ying Zhang3aa29de2013-08-16 15:16:15 +08001924- CONFIG_TPL_BUILD
Thomas Hebb32f2ca22019-11-13 18:18:03 -08001925 Set when the currently-running compilation is for an artifact
1926 that will end up in the TPL (as opposed to the SPL or U-Boot
1927 proper). Code that needs stage-specific behavior should check
1928 this.
Ying Zhang3aa29de2013-08-16 15:16:15 +08001929
Simon Glass4213fc22013-02-24 17:33:14 +00001930- CONFIG_ARCH_MAP_SYSMEM
1931 Generally U-Boot (and in particular the md command) uses
1932 effective address. It is therefore not necessary to regard
1933 U-Boot address as virtual addresses that need to be translated
1934 to physical addresses. However, sandbox requires this, since
1935 it maintains its own little RAM buffer which contains all
1936 addressable memory. This option causes some memory accesses
1937 to be mapped through map_sysmem() / unmap_sysmem().
1938
Simon Glass588a13f2013-02-14 04:18:54 +00001939- CONFIG_X86_RESET_VECTOR
1940 If defined, the x86 reset vector code is included. This is not
1941 needed when U-Boot is running from Coreboot.
Gabe Blackb16f5212012-11-27 21:08:06 +00001942
Karicheri, Muralidharan999d7d32014-04-04 13:16:50 -04001943- CONFIG_SYS_NAND_NO_SUBPAGE_WRITE
1944 Option to disable subpage write in NAND driver
1945 driver that uses this:
Miquel Raynala430fa02018-08-16 17:30:07 +02001946 drivers/mtd/nand/raw/davinci_nand.c
Karicheri, Muralidharan999d7d32014-04-04 13:16:50 -04001947
Timur Tabif2717b42011-11-22 09:21:25 -06001948Freescale QE/FMAN Firmware Support:
1949-----------------------------------
1950
1951The Freescale QUICCEngine (QE) and Frame Manager (FMAN) both support the
1952loading of "firmware", which is encoded in the QE firmware binary format.
1953This firmware often needs to be loaded during U-Boot booting, so macros
1954are used to identify the storage device (NOR flash, SPI, etc) and the address
1955within that device.
1956
Zhao Qiangdcf1d772014-03-21 16:21:44 +08001957- CONFIG_SYS_FMAN_FW_ADDR
1958 The address in the storage device where the FMAN microcode is located. The
Tom Rinicc1e98b2019-05-12 07:59:12 -04001959 meaning of this address depends on which CONFIG_SYS_QE_FMAN_FW_IN_xxx macro
Zhao Qiangdcf1d772014-03-21 16:21:44 +08001960 is also specified.
1961
1962- CONFIG_SYS_QE_FW_ADDR
1963 The address in the storage device where the QE microcode is located. The
Tom Rinicc1e98b2019-05-12 07:59:12 -04001964 meaning of this address depends on which CONFIG_SYS_QE_FMAN_FW_IN_xxx macro
Timur Tabif2717b42011-11-22 09:21:25 -06001965 is also specified.
1966
1967- CONFIG_SYS_QE_FMAN_FW_LENGTH
1968 The maximum possible size of the firmware. The firmware binary format
1969 has a field that specifies the actual size of the firmware, but it
1970 might not be possible to read any part of the firmware unless some
1971 local storage is allocated to hold the entire firmware first.
1972
1973- CONFIG_SYS_QE_FMAN_FW_IN_NOR
1974 Specifies that QE/FMAN firmware is located in NOR flash, mapped as
1975 normal addressable memory via the LBC. CONFIG_SYS_FMAN_FW_ADDR is the
1976 virtual address in NOR flash.
1977
1978- CONFIG_SYS_QE_FMAN_FW_IN_NAND
1979 Specifies that QE/FMAN firmware is located in NAND flash.
1980 CONFIG_SYS_FMAN_FW_ADDR is the offset within NAND flash.
1981
1982- CONFIG_SYS_QE_FMAN_FW_IN_MMC
1983 Specifies that QE/FMAN firmware is located on the primary SD/MMC
1984 device. CONFIG_SYS_FMAN_FW_ADDR is the byte offset on that device.
1985
Liu Gang292dc6c2012-03-08 00:33:18 +00001986- CONFIG_SYS_QE_FMAN_FW_IN_REMOTE
1987 Specifies that QE/FMAN firmware is located in the remote (master)
1988 memory space. CONFIG_SYS_FMAN_FW_ADDR is a virtual address which
Liu Gangfc54c7f2012-08-09 05:10:01 +00001989 can be mapped from slave TLB->slave LAW->slave SRIO or PCIE outbound
1990 window->master inbound window->master LAW->the ucode address in
1991 master's memory space.
Timur Tabif2717b42011-11-22 09:21:25 -06001992
J. German Riverab940ca62014-06-23 15:15:55 -07001993Freescale Layerscape Management Complex Firmware Support:
1994---------------------------------------------------------
1995The Freescale Layerscape Management Complex (MC) supports the loading of
1996"firmware".
1997This firmware often needs to be loaded during U-Boot booting, so macros
1998are used to identify the storage device (NOR flash, SPI, etc) and the address
1999within that device.
2000
2001- CONFIG_FSL_MC_ENET
2002 Enable the MC driver for Layerscape SoCs.
2003
Prabhakar Kushwaha5c055082015-06-02 10:55:52 +05302004Freescale Layerscape Debug Server Support:
2005-------------------------------------------
2006The Freescale Layerscape Debug Server Support supports the loading of
2007"Debug Server firmware" and triggering SP boot-rom.
2008This firmware often needs to be loaded during U-Boot booting.
2009
York Sunc0492142015-12-07 11:08:58 -08002010- CONFIG_SYS_MC_RSV_MEM_ALIGN
2011 Define alignment of reserved memory MC requires
Prabhakar Kushwaha5c055082015-06-02 10:55:52 +05302012
Paul Kocialkowskif3f431a2015-07-26 18:48:15 +02002013Reproducible builds
2014-------------------
2015
2016In order to achieve reproducible builds, timestamps used in the U-Boot build
2017process have to be set to a fixed value.
2018
2019This is done using the SOURCE_DATE_EPOCH environment variable.
2020SOURCE_DATE_EPOCH is to be set on the build host's shell, not as a configuration
2021option for U-Boot or an environment variable in U-Boot.
2022
2023SOURCE_DATE_EPOCH should be set to a number of seconds since the epoch, in UTC.
2024
wdenkc6097192002-11-03 00:24:07 +00002025Building the Software:
2026======================
2027
Wolfgang Denk218ca722008-03-26 10:40:12 +01002028Building U-Boot has been tested in several native build environments
2029and in many different cross environments. Of course we cannot support
2030all possibly existing versions of cross development tools in all
2031(potentially obsolete) versions. In case of tool chain problems we
Naoki Hayama047f6ec2020-10-08 13:17:16 +09002032recommend to use the ELDK (see https://www.denx.de/wiki/DULG/ELDK)
Wolfgang Denk218ca722008-03-26 10:40:12 +01002033which is extensively used to build and test U-Boot.
wdenkc6097192002-11-03 00:24:07 +00002034
Wolfgang Denk218ca722008-03-26 10:40:12 +01002035If you are not using a native environment, it is assumed that you
2036have GNU cross compiling tools available in your path. In this case,
2037you must set the environment variable CROSS_COMPILE in your shell.
2038Note that no changes to the Makefile or any other source files are
2039necessary. For example using the ELDK on a 4xx CPU, please enter:
wdenkc6097192002-11-03 00:24:07 +00002040
Wolfgang Denk218ca722008-03-26 10:40:12 +01002041 $ CROSS_COMPILE=ppc_4xx-
2042 $ export CROSS_COMPILE
wdenkc6097192002-11-03 00:24:07 +00002043
Wolfgang Denk218ca722008-03-26 10:40:12 +01002044U-Boot is intended to be simple to build. After installing the
2045sources you must configure U-Boot for one specific board type. This
wdenkc6097192002-11-03 00:24:07 +00002046is done by typing:
2047
Holger Freytherab584d62014-08-04 09:26:05 +02002048 make NAME_defconfig
wdenkc6097192002-11-03 00:24:07 +00002049
Holger Freytherab584d62014-08-04 09:26:05 +02002050where "NAME_defconfig" is the name of one of the existing configu-
Heinrich Schuchardtecb3a0a2020-02-24 18:36:30 +01002051rations; see configs/*_defconfig for supported names.
wdenk54387ac2003-10-08 22:45:44 +00002052
Heinrich Schuchardtecb3a0a2020-02-24 18:36:30 +01002053Note: for some boards special configuration names may exist; check if
wdenk2729af92004-05-03 20:45:30 +00002054 additional information is available from the board vendor; for
2055 instance, the TQM823L systems are available without (standard)
2056 or with LCD support. You can select such additional "features"
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02002057 when choosing the configuration, i. e.
wdenkc6097192002-11-03 00:24:07 +00002058
Holger Freytherab584d62014-08-04 09:26:05 +02002059 make TQM823L_defconfig
wdenk2729af92004-05-03 20:45:30 +00002060 - will configure for a plain TQM823L, i. e. no LCD support
wdenkc6097192002-11-03 00:24:07 +00002061
Holger Freytherab584d62014-08-04 09:26:05 +02002062 make TQM823L_LCD_defconfig
wdenk2729af92004-05-03 20:45:30 +00002063 - will configure for a TQM823L with U-Boot console on LCD
wdenkc6097192002-11-03 00:24:07 +00002064
wdenk2729af92004-05-03 20:45:30 +00002065 etc.
wdenkc6097192002-11-03 00:24:07 +00002066
wdenkc6097192002-11-03 00:24:07 +00002067
wdenk2729af92004-05-03 20:45:30 +00002068Finally, type "make all", and you should get some working U-Boot
2069images ready for download to / installation on your system:
wdenkc6097192002-11-03 00:24:07 +00002070
wdenk2729af92004-05-03 20:45:30 +00002071- "u-boot.bin" is a raw binary image
2072- "u-boot" is an image in ELF binary format
2073- "u-boot.srec" is in Motorola S-Record format
wdenkc6097192002-11-03 00:24:07 +00002074
Marian Balakowiczbaf31242006-09-07 17:25:40 +02002075By default the build is performed locally and the objects are saved
2076in the source directory. One of the two methods can be used to change
2077this behavior and build U-Boot to some external directory:
2078
20791. Add O= to the make command line invocations:
2080
2081 make O=/tmp/build distclean
Holger Freytherab584d62014-08-04 09:26:05 +02002082 make O=/tmp/build NAME_defconfig
Marian Balakowiczbaf31242006-09-07 17:25:40 +02002083 make O=/tmp/build all
2084
Timo Ketolaadbba992014-11-06 14:39:05 +020020852. Set environment variable KBUILD_OUTPUT to point to the desired location:
Marian Balakowiczbaf31242006-09-07 17:25:40 +02002086
Timo Ketolaadbba992014-11-06 14:39:05 +02002087 export KBUILD_OUTPUT=/tmp/build
Marian Balakowiczbaf31242006-09-07 17:25:40 +02002088 make distclean
Holger Freytherab584d62014-08-04 09:26:05 +02002089 make NAME_defconfig
Marian Balakowiczbaf31242006-09-07 17:25:40 +02002090 make all
2091
Timo Ketolaadbba992014-11-06 14:39:05 +02002092Note that the command line "O=" setting overrides the KBUILD_OUTPUT environment
Marian Balakowiczbaf31242006-09-07 17:25:40 +02002093variable.
2094
Daniel Schwierzeck215bb1c2018-01-26 16:31:04 +01002095User specific CPPFLAGS, AFLAGS and CFLAGS can be passed to the compiler by
2096setting the according environment variables KCPPFLAGS, KAFLAGS and KCFLAGS.
2097For example to treat all compiler warnings as errors:
2098
2099 make KCFLAGS=-Werror
wdenkc6097192002-11-03 00:24:07 +00002100
wdenk2729af92004-05-03 20:45:30 +00002101Please be aware that the Makefiles assume you are using GNU make, so
2102for instance on NetBSD you might need to use "gmake" instead of
2103native "make".
wdenkc6097192002-11-03 00:24:07 +00002104
wdenkc6097192002-11-03 00:24:07 +00002105
wdenk2729af92004-05-03 20:45:30 +00002106If the system board that you have is not listed, then you will need
2107to port U-Boot to your hardware platform. To do this, follow these
2108steps:
wdenkc6097192002-11-03 00:24:07 +00002109
Phil Sutter3c1496c2015-12-25 14:41:18 +010021101. Create a new directory to hold your board specific code. Add any
wdenk2729af92004-05-03 20:45:30 +00002111 files you need. In your board directory, you will need at least
Phil Sutter3c1496c2015-12-25 14:41:18 +01002112 the "Makefile" and a "<board>.c".
21132. Create a new configuration file "include/configs/<board>.h" for
2114 your board.
wdenk2729af92004-05-03 20:45:30 +000021153. If you're porting U-Boot to a new CPU, then also create a new
2116 directory to hold your CPU specific code. Add any files you need.
Holger Freytherab584d62014-08-04 09:26:05 +020021174. Run "make <board>_defconfig" with your new name.
wdenk2729af92004-05-03 20:45:30 +000021185. Type "make", and you should get a working "u-boot.srec" file
2119 to be installed on your target system.
21206. Debug and solve any problems that might arise.
2121 [Of course, this last step is much harder than it sounds.]
wdenkc6097192002-11-03 00:24:07 +00002122
wdenkc6097192002-11-03 00:24:07 +00002123
wdenk2729af92004-05-03 20:45:30 +00002124Testing of U-Boot Modifications, Ports to New Hardware, etc.:
2125==============================================================
wdenkc6097192002-11-03 00:24:07 +00002126
Wolfgang Denk218ca722008-03-26 10:40:12 +01002127If you have modified U-Boot sources (for instance added a new board
2128or support for new devices, a new CPU, etc.) you are expected to
wdenk2729af92004-05-03 20:45:30 +00002129provide feedback to the other developers. The feedback normally takes
Thomas Hebb32f2ca22019-11-13 18:18:03 -08002130the form of a "patch", i.e. a context diff against a certain (latest
Wolfgang Denk218ca722008-03-26 10:40:12 +01002131official or latest in the git repository) version of U-Boot sources.
wdenkc6097192002-11-03 00:24:07 +00002132
Wolfgang Denk218ca722008-03-26 10:40:12 +01002133But before you submit such a patch, please verify that your modifi-
2134cation did not break existing code. At least make sure that *ALL* of
wdenk2729af92004-05-03 20:45:30 +00002135the supported boards compile WITHOUT ANY compiler warnings. To do so,
Simon Glass6de80f22016-07-27 20:33:08 -06002136just run the buildman script (tools/buildman/buildman), which will
2137configure and build U-Boot for ALL supported system. Be warned, this
2138will take a while. Please see the buildman README, or run 'buildman -H'
2139for documentation.
Marian Balakowiczbaf31242006-09-07 17:25:40 +02002140
2141
wdenk2729af92004-05-03 20:45:30 +00002142See also "U-Boot Porting Guide" below.
wdenkc6097192002-11-03 00:24:07 +00002143
wdenkc6097192002-11-03 00:24:07 +00002144
wdenk2729af92004-05-03 20:45:30 +00002145Monitor Commands - Overview:
2146============================
wdenkc6097192002-11-03 00:24:07 +00002147
wdenk2729af92004-05-03 20:45:30 +00002148go - start application at address 'addr'
2149run - run commands in an environment variable
2150bootm - boot application image from memory
2151bootp - boot image via network using BootP/TFTP protocol
Marek Vasut44f074c2012-03-14 21:52:45 +00002152bootz - boot zImage from memory
wdenk2729af92004-05-03 20:45:30 +00002153tftpboot- boot image via network using TFTP protocol
2154 and env variables "ipaddr" and "serverip"
2155 (and eventually "gatewayip")
Simon Glass1fb7cd42011-10-24 18:00:07 +00002156tftpput - upload a file via network using TFTP protocol
wdenk2729af92004-05-03 20:45:30 +00002157rarpboot- boot image via network using RARP/TFTP protocol
2158diskboot- boot from IDE devicebootd - boot default, i.e., run 'bootcmd'
2159loads - load S-Record file over serial line
2160loadb - load binary file over serial line (kermit mode)
Rui Miguel Silvabfef72e2022-05-11 10:55:40 +01002161loadm - load binary blob from source address to destination address
wdenk2729af92004-05-03 20:45:30 +00002162md - memory display
2163mm - memory modify (auto-incrementing)
2164nm - memory modify (constant address)
2165mw - memory write (fill)
Simon Glassbdded202020-06-02 19:26:49 -06002166ms - memory search
wdenk2729af92004-05-03 20:45:30 +00002167cp - memory copy
2168cmp - memory compare
2169crc32 - checksum calculation
Peter Tyser0f89c542009-04-18 22:34:03 -05002170i2c - I2C sub-system
wdenk2729af92004-05-03 20:45:30 +00002171sspi - SPI utility commands
2172base - print or set address offset
2173printenv- print environment variables
Pragnesh Patel9e9a5302020-12-22 11:30:05 +05302174pwm - control pwm channels
wdenk2729af92004-05-03 20:45:30 +00002175setenv - set environment variables
2176saveenv - save environment variables to persistent storage
2177protect - enable or disable FLASH write protection
2178erase - erase FLASH memory
2179flinfo - print FLASH memory information
Karl O. Pinc10635af2012-08-03 05:57:21 +00002180nand - NAND memory operations (see doc/README.nand)
wdenk2729af92004-05-03 20:45:30 +00002181bdinfo - print Board Info structure
2182iminfo - print header information for application image
2183coninfo - print console devices and informations
2184ide - IDE sub-system
2185loop - infinite loop on address range
wdenk56523f12004-07-11 17:40:54 +00002186loopw - infinite write loop on address range
wdenk2729af92004-05-03 20:45:30 +00002187mtest - simple RAM test
2188icache - enable or disable instruction cache
2189dcache - enable or disable data cache
2190reset - Perform RESET of the CPU
2191echo - echo args to console
2192version - print monitor version
2193help - print online help
2194? - alias for 'help'
wdenkc6097192002-11-03 00:24:07 +00002195
wdenkc6097192002-11-03 00:24:07 +00002196
wdenk2729af92004-05-03 20:45:30 +00002197Monitor Commands - Detailed Description:
2198========================================
wdenkc6097192002-11-03 00:24:07 +00002199
wdenk2729af92004-05-03 20:45:30 +00002200TODO.
wdenkc6097192002-11-03 00:24:07 +00002201
wdenk2729af92004-05-03 20:45:30 +00002202For now: just type "help <command>".
wdenkc6097192002-11-03 00:24:07 +00002203
2204
wdenk2729af92004-05-03 20:45:30 +00002205Note for Redundant Ethernet Interfaces:
2206=======================================
wdenkf07771c2003-05-28 08:06:31 +00002207
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02002208Some boards come with redundant Ethernet interfaces; U-Boot supports
wdenk2729af92004-05-03 20:45:30 +00002209such configurations and is capable of automatic selection of a
2210"working" interface when needed. MAC assignment works as follows:
wdenkf07771c2003-05-28 08:06:31 +00002211
wdenk2729af92004-05-03 20:45:30 +00002212Network interfaces are numbered eth0, eth1, eth2, ... Corresponding
2213MAC addresses can be stored in the environment as "ethaddr" (=>eth0),
2214"eth1addr" (=>eth1), "eth2addr", ...
wdenkf07771c2003-05-28 08:06:31 +00002215
wdenk2729af92004-05-03 20:45:30 +00002216If the network interface stores some valid MAC address (for instance
2217in SROM), this is used as default address if there is NO correspon-
2218ding setting in the environment; if the corresponding environment
2219variable is set, this overrides the settings in the card; that means:
wdenkf07771c2003-05-28 08:06:31 +00002220
wdenk2729af92004-05-03 20:45:30 +00002221o If the SROM has a valid MAC address, and there is no address in the
2222 environment, the SROM's address is used.
wdenkc6097192002-11-03 00:24:07 +00002223
wdenk2729af92004-05-03 20:45:30 +00002224o If there is no valid address in the SROM, and a definition in the
2225 environment exists, then the value from the environment variable is
2226 used.
wdenkc6097192002-11-03 00:24:07 +00002227
wdenk2729af92004-05-03 20:45:30 +00002228o If both the SROM and the environment contain a MAC address, and
2229 both addresses are the same, this MAC address is used.
wdenkc6097192002-11-03 00:24:07 +00002230
wdenk2729af92004-05-03 20:45:30 +00002231o If both the SROM and the environment contain a MAC address, and the
2232 addresses differ, the value from the environment is used and a
2233 warning is printed.
wdenkc6097192002-11-03 00:24:07 +00002234
wdenk2729af92004-05-03 20:45:30 +00002235o If neither SROM nor the environment contain a MAC address, an error
Joe Hershbergerbef10142015-05-04 14:55:13 -05002236 is raised. If CONFIG_NET_RANDOM_ETHADDR is defined, then in this case
2237 a random, locally-assigned MAC is used.
wdenkc6097192002-11-03 00:24:07 +00002238
Ben Warrenecee9322010-04-26 11:11:46 -07002239If Ethernet drivers implement the 'write_hwaddr' function, valid MAC addresses
Wolfgang Denkc0f40852011-10-26 10:21:21 +00002240will be programmed into hardware as part of the initialization process. This
Ben Warrenecee9322010-04-26 11:11:46 -07002241may be skipped by setting the appropriate 'ethmacskip' environment variable.
2242The naming convention is as follows:
2243"ethmacskip" (=>eth0), "eth1macskip" (=>eth1) etc.
wdenkc6097192002-11-03 00:24:07 +00002244
wdenk2729af92004-05-03 20:45:30 +00002245Image Formats:
2246==============
wdenkc6097192002-11-03 00:24:07 +00002247
Marian Balakowicz3310c542008-03-12 12:13:13 +01002248U-Boot is capable of booting (and performing other auxiliary operations on)
2249images in two formats:
2250
2251New uImage format (FIT)
2252-----------------------
2253
2254Flexible and powerful format based on Flattened Image Tree -- FIT (similar
2255to Flattened Device Tree). It allows the use of images with multiple
2256components (several kernels, ramdisks, etc.), with contents protected by
2257SHA1, MD5 or CRC32. More details are found in the doc/uImage.FIT directory.
2258
2259
2260Old uImage format
2261-----------------
2262
2263Old image format is based on binary files which can be basically anything,
2264preceded by a special header; see the definitions in include/image.h for
2265details; basically, the header defines the following image properties:
wdenkc6097192002-11-03 00:24:07 +00002266
wdenk2729af92004-05-03 20:45:30 +00002267* Target Operating System (Provisions for OpenBSD, NetBSD, FreeBSD,
2268 4.4BSD, Linux, SVR4, Esix, Solaris, Irix, SCO, Dell, NCR, VxWorks,
Peter Tyserf5ed9e32008-09-08 14:56:49 -05002269 LynxOS, pSOS, QNX, RTEMS, INTEGRITY;
Thomas Huth0797e732021-11-13 18:13:50 +01002270 Currently supported: Linux, NetBSD, VxWorks, QNX, RTEMS, INTEGRITY).
Andy Shevchenkodaab59a2017-07-05 16:25:22 +03002271* Target CPU Architecture (Provisions for Alpha, ARM, Intel x86,
Tom Rini11232132022-04-06 09:21:25 -04002272 IA64, MIPS, Nios II, PowerPC, IBM S390, SuperH, Sparc, Sparc 64 Bit;
2273 Currently supported: ARM, Intel x86, MIPS, Nios II, PowerPC).
wdenk2729af92004-05-03 20:45:30 +00002274* Compression Type (uncompressed, gzip, bzip2)
2275* Load Address
2276* Entry Point
2277* Image Name
2278* Image Timestamp
wdenkc6097192002-11-03 00:24:07 +00002279
wdenk2729af92004-05-03 20:45:30 +00002280The header is marked by a special Magic Number, and both the header
2281and the data portions of the image are secured against corruption by
2282CRC32 checksums.
wdenkc6097192002-11-03 00:24:07 +00002283
wdenkc6097192002-11-03 00:24:07 +00002284
wdenk2729af92004-05-03 20:45:30 +00002285Linux Support:
2286==============
wdenkc6097192002-11-03 00:24:07 +00002287
wdenk2729af92004-05-03 20:45:30 +00002288Although U-Boot should support any OS or standalone application
2289easily, the main focus has always been on Linux during the design of
2290U-Boot.
wdenkc6097192002-11-03 00:24:07 +00002291
wdenk2729af92004-05-03 20:45:30 +00002292U-Boot includes many features that so far have been part of some
2293special "boot loader" code within the Linux kernel. Also, any
2294"initrd" images to be used are no longer part of one big Linux image;
2295instead, kernel and "initrd" are separate images. This implementation
2296serves several purposes:
wdenkc6097192002-11-03 00:24:07 +00002297
wdenk2729af92004-05-03 20:45:30 +00002298- the same features can be used for other OS or standalone
2299 applications (for instance: using compressed images to reduce the
2300 Flash memory footprint)
wdenkc6097192002-11-03 00:24:07 +00002301
wdenk2729af92004-05-03 20:45:30 +00002302- it becomes much easier to port new Linux kernel versions because
2303 lots of low-level, hardware dependent stuff are done by U-Boot
wdenkc6097192002-11-03 00:24:07 +00002304
wdenk2729af92004-05-03 20:45:30 +00002305- the same Linux kernel image can now be used with different "initrd"
2306 images; of course this also means that different kernel images can
2307 be run with the same "initrd". This makes testing easier (you don't
2308 have to build a new "zImage.initrd" Linux image when you just
2309 change a file in your "initrd"). Also, a field-upgrade of the
2310 software is easier now.
wdenkc6097192002-11-03 00:24:07 +00002311
wdenkc6097192002-11-03 00:24:07 +00002312
wdenk2729af92004-05-03 20:45:30 +00002313Linux HOWTO:
2314============
wdenkc6097192002-11-03 00:24:07 +00002315
wdenk2729af92004-05-03 20:45:30 +00002316Porting Linux to U-Boot based systems:
2317---------------------------------------
wdenkc6097192002-11-03 00:24:07 +00002318
wdenk2729af92004-05-03 20:45:30 +00002319U-Boot cannot save you from doing all the necessary modifications to
2320configure the Linux device drivers for use with your target hardware
2321(no, we don't intend to provide a full virtual machine interface to
2322Linux :-).
wdenkc6097192002-11-03 00:24:07 +00002323
Stefan Roesea47a12b2010-04-15 16:07:28 +02002324But now you can ignore ALL boot loader code (in arch/powerpc/mbxboot).
wdenkc6097192002-11-03 00:24:07 +00002325
wdenk2729af92004-05-03 20:45:30 +00002326Just make sure your machine specific header file (for instance
2327include/asm-ppc/tqm8xx.h) includes the same definit