blob: bbf96e64c89a184ff10edf0a570e3353476accc8 [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
Heinrich Schuchardt0c4759f2023-01-25 19:14:59 +010031In general, all boards for which a default configuration file exists in the
32configs/ directory 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
Heinrich Schuchardt0c4759f2023-01-25 19:14:59 +010035In case of problems you can use
wdenkc6097192002-11-03 00:24:07 +000036
Heinrich Schuchardt0c4759f2023-01-25 19:14:59 +010037 scripts/get_maintainer.pl <path>
Robert P. J. Dayadb9d852012-11-14 02:03:20 +000038
Heinrich Schuchardt0c4759f2023-01-25 19:14:59 +010039to identify the people or companies responsible for various boards and
40subsystems. Or have a look at the git log.
Robert P. J. Dayadb9d852012-11-14 02:03:20 +000041
wdenkc6097192002-11-03 00:24:07 +000042
43Where to get help:
44==================
45
wdenk24ee89b2002-11-03 17:56:27 +000046In case you have questions about, problems with or contributions for
Robert P. J. Day7207b362015-12-19 07:16:10 -050047U-Boot, you should send a message to the U-Boot mailing list at
Peter Tyser0c325652008-09-10 09:18:34 -050048<u-boot@lists.denx.de>. There is also an archive of previous traffic
49on the mailing list - please search the archive before asking FAQ's.
Naoki Hayama6681bbb2020-10-08 13:16:18 +090050Please see https://lists.denx.de/pipermail/u-boot and
51https://marc.info/?l=u-boot
wdenkc6097192002-11-03 00:24:07 +000052
Wolfgang Denk218ca722008-03-26 10:40:12 +010053Where to get source code:
54=========================
55
Robert P. J. Day7207b362015-12-19 07:16:10 -050056The U-Boot source code is maintained in the Git repository at
Heinrich Schuchardta3bbd0b2021-02-24 13:19:04 +010057https://source.denx.de/u-boot/u-boot.git ; you can browse it online at
58https://source.denx.de/u-boot/u-boot
Wolfgang Denk218ca722008-03-26 10:40:12 +010059
Naoki Hayamac4bd51e2020-10-08 13:16:25 +090060The "Tags" links on this page allow you to download tarballs of
Marcel Ziswiler11ccc332008-07-09 08:17:15 +020061any version you might be interested in. Official releases are also
Naoki Hayamac4bd51e2020-10-08 13:16:25 +090062available from the DENX file server through HTTPS or FTP.
63https://ftp.denx.de/pub/u-boot/
64ftp://ftp.denx.de/pub/u-boot/
Wolfgang Denk218ca722008-03-26 10:40:12 +010065
66
wdenkc6097192002-11-03 00:24:07 +000067Where we come from:
68===================
69
70- start from 8xxrom sources
Naoki Hayama047f6ec2020-10-08 13:17:16 +090071- create PPCBoot project (https://sourceforge.net/projects/ppcboot)
wdenkc6097192002-11-03 00:24:07 +000072- clean up code
73- make it easier to add custom boards
74- make it possible to add other [PowerPC] CPUs
75- extend functions, especially:
76 * Provide extended interface to Linux boot loader
77 * S-Record download
78 * network boot
Simon Glass9e5616d2019-08-01 09:47:14 -060079 * ATA disk / SCSI ... boot
Naoki Hayama047f6ec2020-10-08 13:17:16 +090080- create ARMBoot project (https://sourceforge.net/projects/armboot)
wdenkc6097192002-11-03 00:24:07 +000081- add other CPU families (starting with ARM)
Naoki Hayama047f6ec2020-10-08 13:17:16 +090082- create U-Boot project (https://sourceforge.net/projects/u-boot)
83- current project page: see https://www.denx.de/wiki/U-Boot
wdenk24ee89b2002-11-03 17:56:27 +000084
85
86Names and Spelling:
87===================
88
89The "official" name of this project is "Das U-Boot". The spelling
90"U-Boot" shall be used in all written text (documentation, comments
91in source files etc.). Example:
92
93 This is the README file for the U-Boot project.
94
95File names etc. shall be based on the string "u-boot". Examples:
96
97 include/asm-ppc/u-boot.h
98
99 #include <asm/u-boot.h>
100
101Variable names, preprocessor constants etc. shall be either based on
102the string "u_boot" or on "U_BOOT". Example:
103
104 U_BOOT_VERSION u_boot_logo
105 IH_OS_U_BOOT u_boot_hush_start
wdenkc6097192002-11-03 00:24:07 +0000106
107
wdenkc6097192002-11-03 00:24:07 +0000108Software Configuration:
109=======================
110
wdenkc6097192002-11-03 00:24:07 +0000111Selection of Processor Architecture and Board Type:
112---------------------------------------------------
113
114For all supported boards there are ready-to-use default
Holger Freytherab584d62014-08-04 09:26:05 +0200115configurations available; just type "make <board_name>_defconfig".
wdenkc6097192002-11-03 00:24:07 +0000116
117Example: For a TQM823L module type:
118
119 cd u-boot
Holger Freytherab584d62014-08-04 09:26:05 +0200120 make TQM823L_defconfig
wdenkc6097192002-11-03 00:24:07 +0000121
Robert P. J. Day7207b362015-12-19 07:16:10 -0500122Note: If you're looking for the default configuration file for a board
123you're sure used to be there but is now missing, check the file
124doc/README.scrapyard for a list of no longer supported boards.
wdenkc6097192002-11-03 00:24:07 +0000125
Simon Glass75b3c3a2014-03-22 17:12:59 -0600126Sandbox Environment:
127--------------------
128
129U-Boot can be built natively to run on a Linux host using the 'sandbox'
130board. This allows feature development which is not board- or architecture-
131specific to be undertaken on a native platform. The sandbox is also used to
132run some of U-Boot's tests.
133
Heinrich Schuchardtcf69dc72023-01-25 19:14:56 +0100134See doc/arch/sandbox/sandbox.rst for more details.
Simon Glass75b3c3a2014-03-22 17:12:59 -0600135
136
Simon Glassdb910352015-03-03 08:03:00 -0700137Board Initialisation Flow:
138--------------------------
139
140This is the intended start-up flow for boards. This should apply for both
Robert P. J. Day7207b362015-12-19 07:16:10 -0500141SPL and U-Boot proper (i.e. they both follow the same rules).
Simon Glassdb910352015-03-03 08:03:00 -0700142
Robert P. J. Day7207b362015-12-19 07:16:10 -0500143Note: "SPL" stands for "Secondary Program Loader," which is explained in
144more detail later in this file.
145
146At present, SPL mostly uses a separate code path, but the function names
147and roles of each function are the same. Some boards or architectures
148may not conform to this. At least most ARM boards which use
149CONFIG_SPL_FRAMEWORK conform to this.
150
151Execution typically starts with an architecture-specific (and possibly
152CPU-specific) start.S file, such as:
153
154 - arch/arm/cpu/armv7/start.S
155 - arch/powerpc/cpu/mpc83xx/start.S
156 - arch/mips/cpu/start.S
157
158and so on. From there, three functions are called; the purpose and
159limitations of each of these functions are described below.
Simon Glassdb910352015-03-03 08:03:00 -0700160
161lowlevel_init():
162 - purpose: essential init to permit execution to reach board_init_f()
163 - no global_data or BSS
164 - there is no stack (ARMv7 may have one but it will soon be removed)
165 - must not set up SDRAM or use console
166 - must only do the bare minimum to allow execution to continue to
167 board_init_f()
168 - this is almost never needed
169 - return normally from this function
170
171board_init_f():
172 - purpose: set up the machine ready for running board_init_r():
173 i.e. SDRAM and serial UART
174 - global_data is available
175 - stack is in SRAM
176 - BSS is not available, so you cannot use global/static variables,
177 only stack variables and global_data
178
179 Non-SPL-specific notes:
180 - dram_init() is called to set up DRAM. If already done in SPL this
181 can do nothing
182
183 SPL-specific notes:
184 - you can override the entire board_init_f() function with your own
185 version as needed.
186 - preloader_console_init() can be called here in extremis
187 - should set up SDRAM, and anything needed to make the UART work
Naoki Hayama499696e2020-09-24 15:57:19 +0900188 - there is no need to clear BSS, it will be done by crt0.S
Andreas Dannenberg14254652019-08-08 12:54:49 -0500189 - for specific scenarios on certain architectures an early BSS *can*
190 be made available (via CONFIG_SPL_EARLY_BSS by moving the clearing
191 of BSS prior to entering board_init_f()) but doing so is discouraged.
192 Instead it is strongly recommended to architect any code changes
193 or additions such to not depend on the availability of BSS during
194 board_init_f() as indicated in other sections of this README to
195 maintain compatibility and consistency across the entire code base.
Simon Glassdb910352015-03-03 08:03:00 -0700196 - must return normally from this function (don't call board_init_r()
197 directly)
198
199Here the BSS is cleared. For SPL, if CONFIG_SPL_STACK_R is defined, then at
200this point the stack and global_data are relocated to below
201CONFIG_SPL_STACK_R_ADDR. For non-SPL, U-Boot is relocated to run at the top of
202memory.
203
204board_init_r():
205 - purpose: main execution, common code
206 - global_data is available
207 - SDRAM is available
208 - BSS is available, all static/global variables can be used
209 - execution eventually continues to main_loop()
210
211 Non-SPL-specific notes:
212 - U-Boot is relocated to the top of memory and is now running from
213 there.
214
215 SPL-specific notes:
216 - stack is optionally in SDRAM, if CONFIG_SPL_STACK_R is defined and
Ashish Kumar63b23162017-08-11 11:09:14 +0530217 CONFIG_SYS_FSL_HAS_CCI400
218
219 Defined For SoC that has cache coherent interconnect
220 CCN-400
wdenk7f6c2cb2002-11-10 22:06:23 +0000221
Ashish Kumarc055cee2017-08-18 10:54:36 +0530222 CONFIG_SYS_FSL_HAS_CCN504
223
224 Defined for SoC that has cache coherent interconnect CCN-504
225
wdenkc6097192002-11-03 00:24:07 +0000226The following options need to be configured:
227
Kim Phillips26281142007-08-10 13:28:25 -0500228- CPU Type: Define exactly one, e.g. CONFIG_MPC85XX.
wdenkc6097192002-11-03 00:24:07 +0000229
Kim Phillips26281142007-08-10 13:28:25 -0500230- Board Type: Define exactly one, e.g. CONFIG_MPC8540ADS.
Wolfgang Denk6ccec442006-10-24 14:42:37 +0200231
Kumar Gala66412c62011-02-18 05:40:54 -0600232- 85xx CPU Options:
York Sunffd06e02012-10-08 07:44:30 +0000233 CONFIG_SYS_PPC64
234
235 Specifies that the core is a 64-bit PowerPC implementation (implements
236 the "64" category of the Power ISA). This is necessary for ePAPR
237 compliance, among other possible reasons.
238
Scott Wood33eee332012-08-14 10:14:53 +0000239 CONFIG_SYS_FSL_ERRATUM_A004510
240
241 Enables a workaround for erratum A004510. If set,
242 then CONFIG_SYS_FSL_ERRATUM_A004510_SVR_REV and
Tom Rini6cc04542022-10-28 20:27:13 -0400243 CFG_SYS_FSL_CORENET_SNOOPVEC_COREONLY must be set.
Scott Wood33eee332012-08-14 10:14:53 +0000244
245 CONFIG_SYS_FSL_ERRATUM_A004510_SVR_REV
246 CONFIG_SYS_FSL_ERRATUM_A004510_SVR_REV2 (optional)
247
248 Defines one or two SoC revisions (low 8 bits of SVR)
249 for which the A004510 workaround should be applied.
250
251 The rest of SVR is either not relevant to the decision
252 of whether the erratum is present (e.g. p2040 versus
253 p2041) or is implied by the build target, which controls
254 whether CONFIG_SYS_FSL_ERRATUM_A004510 is set.
255
256 See Freescale App Note 4493 for more information about
257 this erratum.
258
Tom Rini6cc04542022-10-28 20:27:13 -0400259 CFG_SYS_FSL_CORENET_SNOOPVEC_COREONLY
Scott Wood33eee332012-08-14 10:14:53 +0000260
261 This is the value to write into CCSR offset 0x18600
262 according to the A004510 workaround.
263
Priyanka Jainb1359912013-12-17 14:25:52 +0530264 CONFIG_SYS_FSL_SINGLE_SOURCE_CLK
265 Single Source Clock is clocking mode present in some of FSL SoC's.
266 In this mode, a single differential clock is used to supply
267 clocks to the sysclock, ddrclock and usbclock.
268
Daniel Schwierzeck6cb461b2012-04-02 02:57:56 +0000269- Generic CPU options:
Daniel Schwierzeck6cb461b2012-04-02 02:57:56 +0000270
York Sun5614e712013-09-30 09:22:09 -0700271 CONFIG_SYS_FSL_DDR
272 Freescale DDR driver in use. This type of DDR controller is
Tom Rini1c588572021-05-14 21:34:26 -0400273 found in mpc83xx, mpc85xx as well as some ARM core SoCs.
York Sun5614e712013-09-30 09:22:09 -0700274
Tom Rini6cc04542022-10-28 20:27:13 -0400275 CFG_SYS_FSL_DDR_ADDR
York Sun5614e712013-09-30 09:22:09 -0700276 Freescale DDR memory-mapped register base.
277
Prabhakar Kushwaha1c407072017-02-02 15:01:26 +0530278 CONFIG_SYS_FSL_IFC_CLK_DIV
279 Defines divider of platform clock(clock input to IFC controller).
280
Prabhakar Kushwahaadd63f92017-02-02 15:02:00 +0530281 CONFIG_SYS_FSL_LBC_CLK_DIV
282 Defines divider of platform clock(clock input to eLBC controller).
283
Tom Rini6cc04542022-10-28 20:27:13 -0400284 CFG_SYS_FSL_DDR_SDRAM_BASE_PHY
York Sun6b9e3092014-02-10 13:59:43 -0800285 Physical address from the view of DDR controllers. It is the
Tom Rini65cc0e22022-11-16 13:10:41 -0500286 same as CFG_SYS_DDR_SDRAM_BASE for all Power SoCs. But
York Sun6b9e3092014-02-10 13:59:43 -0800287 it could be different for ARM SoCs.
288
Christian Rieschb67d8812012-02-02 00:44:39 +0000289- ARM options:
Tom Rini65cc0e22022-11-16 13:10:41 -0500290 CFG_SYS_EXCEPTION_VECTORS_HIGH
Christian Rieschb67d8812012-02-02 00:44:39 +0000291
292 Select high exception vectors of the ARM core, e.g., do not
293 clear the V bit of the c1 register of CP15.
294
York Sun207774b2015-03-20 19:28:08 -0700295 COUNTER_FREQUENCY
296 Generic timer clock source frequency.
297
298 COUNTER_FREQUENCY_REAL
299 Generic timer clock source frequency if the real clock is
300 different from COUNTER_FREQUENCY, and can only be determined
301 at run time.
302
Stephen Warren73c38932015-01-19 16:25:52 -0700303- Tegra SoC options:
304 CONFIG_TEGRA_SUPPORT_NON_SECURE
305
306 Support executing U-Boot in non-secure (NS) mode. Certain
307 impossible actions will be skipped if the CPU is in NS mode,
308 such as ARM architectural timer initialization.
309
wdenk5da627a2003-10-09 20:09:04 +0000310- Linux Kernel Interface:
Gerald Van Barenfec6d9e2008-06-03 20:34:45 -0400311 CONFIG_OF_LIBFDT
Wolfgang Denkf57f70a2005-10-13 01:45:54 +0200312
313 New kernel versions are expecting firmware settings to be
Gerald Van Baren213bf8c2007-03-31 12:23:51 -0400314 passed using flattened device trees (based on open firmware
315 concepts).
316
317 CONFIG_OF_LIBFDT
318 * New libfdt-based support
319 * Adds the "fdt" command
Kim Phillips3bb342f2007-08-10 14:34:14 -0500320 * The bootm command automatically updates the fdt
Gerald Van Baren213bf8c2007-03-31 12:23:51 -0400321
Wolfgang Denkf57f70a2005-10-13 01:45:54 +0200322 OF_TBCLK - The timebase frequency.
323
Marcel Ziswiler11ccc332008-07-09 08:17:15 +0200324 boards with QUICC Engines require OF_QE to set UCC MAC
325 addresses
Kim Phillips3bb342f2007-08-10 14:34:14 -0500326
Heiko Schocher3887c3f2009-09-23 07:56:08 +0200327 CONFIG_OF_IDE_FIXUP
328
329 U-Boot can detect if an IDE device is present or not.
330 If not, and this new config option is activated, U-Boot
331 removes the ATA node from the DTS before booting Linux,
332 so the Linux IDE driver does not probe the device and
333 crash. This is needed for buggy hardware (uc101) where
334 no pull down resistor is connected to the signal IDE5V_DD7.
335
Niklaus Giger0b2f4ec2008-11-03 22:13:47 +0100336- vxWorks boot parameters:
337
338 bootvx constructs a valid bootline using the following
Bin Meng9e98b7e2015-10-07 20:19:17 -0700339 environments variables: bootdev, bootfile, ipaddr, netmask,
340 serverip, gatewayip, hostname, othbootargs.
Niklaus Giger0b2f4ec2008-11-03 22:13:47 +0100341 It loads the vxWorks image pointed bootfile.
342
Naoki Hayama81a05d92020-10-08 13:17:08 +0900343 Note: If a "bootargs" environment is defined, it will override
Niklaus Giger0b2f4ec2008-11-03 22:13:47 +0100344 the defaults discussed just above.
345
Aneesh V93bc2192011-06-16 23:30:51 +0000346- Cache Configuration for ARM:
Tom Rini65cc0e22022-11-16 13:10:41 -0500347 CFG_SYS_PL310_BASE - Physical base address of PL310
Aneesh V93bc2192011-06-16 23:30:51 +0000348 controller register space
349
wdenk6705d812004-08-02 23:22:59 +0000350- Serial Ports:
Tom Rinif410d0a2022-12-04 10:13:30 -0500351 CFG_PL011_CLOCK
wdenk6705d812004-08-02 23:22:59 +0000352
353 If you have Amba PrimeCell PL011 UARTs, set this variable to
354 the clock speed of the UARTs.
355
Tom Rinib8615742022-12-04 10:13:31 -0500356 CFG_PL01x_PORTS
wdenk6705d812004-08-02 23:22:59 +0000357
358 If you have Amba PrimeCell PL010 or PL011 UARTs on your board,
359 define this to a list of base addresses for each (supported)
360 port. See e.g. include/configs/versatile.h
361
Karicheri, Muralidharand57dee52014-04-09 15:38:46 -0400362 CONFIG_SERIAL_HW_FLOW_CONTROL
363
364 Define this variable to enable hw flow control in serial driver.
365 Current user of this option is drivers/serial/nsl16550.c driver
wdenk6705d812004-08-02 23:22:59 +0000366
Simon Glass302a6482016-03-13 19:07:28 -0600367- Removal of commands
368 If no commands are needed to boot, you can disable
369 CONFIG_CMDLINE to remove them. In this case, the command line
370 will not be available, and when U-Boot wants to execute the
371 boot command (on start-up) it will call board_run_command()
372 instead. This can reduce image size significantly for very
373 simple boot procedures.
374
Wolfgang Denka5ecbe62013-03-23 23:50:31 +0000375- Regular expression support:
376 CONFIG_REGEX
Wolfgang Denk93e14592013-10-04 17:43:24 +0200377 If this variable is defined, U-Boot is linked against
378 the SLRE (Super Light Regular Expression) library,
379 which adds regex support to some commands, as for
380 example "env grep" and "setexpr".
Wolfgang Denka5ecbe62013-03-23 23:50:31 +0000381
wdenkc6097192002-11-03 00:24:07 +0000382- Watchdog:
Tom Rini6e7df1d2023-01-10 11:19:45 -0500383 CFG_SYS_WATCHDOG_FREQ
Rasmus Villemoes933ada52021-04-14 09:18:22 +0200384 Some platforms automatically call WATCHDOG_RESET()
385 from the timer interrupt handler every
Tom Rini6e7df1d2023-01-10 11:19:45 -0500386 CFG_SYS_WATCHDOG_FREQ interrupts. If not set by the
Rasmus Villemoes933ada52021-04-14 09:18:22 +0200387 board configuration file, a default of CONFIG_SYS_HZ/2
Tom Rini6e7df1d2023-01-10 11:19:45 -0500388 (i.e. 500) is used. Setting CFG_SYS_WATCHDOG_FREQ
Rasmus Villemoes933ada52021-04-14 09:18:22 +0200389 to 0 disables calling WATCHDOG_RESET() from the timer
390 interrupt.
391
Peter Tysere92739d2008-12-17 16:36:21 -0600392- GPIO Support:
Tom Rini65cc0e22022-11-16 13:10:41 -0500393 The CFG_SYS_I2C_PCA953X_WIDTH option specifies a list of
Chris Packham5dec49c2010-12-19 10:12:13 +0000394 chip-ngpio pairs that tell the PCA953X driver the number of
395 pins supported by a particular chip.
396
Peter Tysere92739d2008-12-17 16:36:21 -0600397 Note that if the GPIO device uses I2C, then the I2C interface
398 must also be configured. See I2C Support, below.
399
Simon Glassaa532332014-06-11 23:29:41 -0600400- I/O tracing:
401 When CONFIG_IO_TRACE is selected, U-Boot intercepts all I/O
402 accesses and can checksum them or write a list of them out
403 to memory. See the 'iotrace' command for details. This is
404 useful for testing device drivers since it can confirm that
405 the driver behaves the same way before and after a code
406 change. Currently this is supported on sandbox and arm. To
407 add support for your architecture, add '#include <iotrace.h>'
408 to the bottom of arch/<arch>/include/asm/io.h and test.
409
410 Example output from the 'iotrace stats' command is below.
411 Note that if the trace buffer is exhausted, the checksum will
412 still continue to operate.
413
414 iotrace is enabled
415 Start: 10000000 (buffer start address)
416 Size: 00010000 (buffer size)
417 Offset: 00000120 (current buffer offset)
418 Output: 10000120 (start + offset)
419 Count: 00000018 (number of trace records)
420 CRC32: 9526fb66 (CRC32 of all trace records)
421
wdenkc6097192002-11-03 00:24:07 +0000422- Timestamp Support:
423
wdenk43d96162003-03-06 00:02:04 +0000424 When CONFIG_TIMESTAMP is selected, the timestamp
425 (date and time) of an image is printed by image
426 commands like bootm or iminfo. This option is
Jon Loeliger602ad3b2007-06-11 19:03:39 -0500427 automatically enabled when you select CONFIG_CMD_DATE .
wdenkc6097192002-11-03 00:24:07 +0000428
Karl O. Pinc923c46f2012-08-16 06:20:15 +0000429- Partition Labels (disklabels) Supported:
430 Zero or more of the following:
431 CONFIG_MAC_PARTITION Apple's MacOS partition table.
Karl O. Pinc923c46f2012-08-16 06:20:15 +0000432 CONFIG_ISO_PARTITION ISO partition table, used on CDROM etc.
433 CONFIG_EFI_PARTITION GPT partition table, common when EFI is the
434 bootloader. Note 2TB partition limit; see
435 disk/part_efi.c
Simon Glassc649e3c2016-05-01 11:36:02 -0600436 CONFIG_SCSI) you must configure support for at
Karl O. Pinc923c46f2012-08-16 06:20:15 +0000437 least one non-MTD partition type as well.
wdenkc6097192002-11-03 00:24:07 +0000438
wdenkc6097192002-11-03 00:24:07 +0000439- NETWORK Support (PCI):
Kyle Moffettce5207e2011-10-18 11:05:29 +0000440 CONFIG_E1000_SPI
441 Utility code for direct access to the SPI bus on Intel 8257x.
442 This does not do anything useful unless you set at least one
443 of CONFIG_CMD_E1000 or CONFIG_E1000_SPI_GENERIC.
444
wdenkc6097192002-11-03 00:24:07 +0000445 CONFIG_NATSEMI
446 Support for National dp83815 chips.
447
448 CONFIG_NS8382X
449 Support for National dp8382[01] gigabit chips.
450
wdenk45219c42003-05-12 21:50:16 +0000451- NETWORK Support (other):
Rob Herringefdd7312011-12-15 11:15:49 +0000452 CONFIG_CALXEDA_XGMAC
453 Support for the Calxeda XGMAC device
454
Ashok3bb46d22012-10-15 06:20:47 +0000455 CONFIG_LAN91C96
wdenk45219c42003-05-12 21:50:16 +0000456 Support for SMSC's LAN91C96 chips.
457
wdenk45219c42003-05-12 21:50:16 +0000458 CONFIG_LAN91C96_USE_32_BIT
459 Define this to enable 32 bit addressing
460
Tom Rini6e7df1d2023-01-10 11:19:45 -0500461 CFG_SYS_DAVINCI_EMAC_PHY_COUNT
Heiko Schocherdc02bad2011-11-15 10:00:04 -0500462 Define this if you have more then 3 PHYs.
463
Macpaul Linb3dbf4a52010-12-21 16:59:46 +0800464 CONFIG_FTGMAC100
465 Support for Faraday's FTGMAC100 Gigabit SoC Ethernet
466
467 CONFIG_FTGMAC100_EGIGA
468 Define this to use GE link update with gigabit PHY.
469 Define this if FTGMAC100 is connected to gigabit PHY.
470 If your system has 10/100 PHY only, it might not occur
471 wrong behavior. Because PHY usually return timeout or
472 useless data when polling gigabit status and gigabit
473 control registers. This behavior won't affect the
474 correctnessof 10/100 link speed update.
475
Yoshihiro Shimoda3d0075f2011-01-27 10:06:03 +0900476 CONFIG_SH_ETHER
477 Support for Renesas on-chip Ethernet controller
478
Tom Rini97148cb2022-12-04 10:13:52 -0500479 CFG_SH_ETHER_USE_PORT
Yoshihiro Shimoda3d0075f2011-01-27 10:06:03 +0900480 Define the number of ports to be used
481
Tom Rini7c480ba2022-12-04 10:13:50 -0500482 CFG_SH_ETHER_PHY_ADDR
Yoshihiro Shimoda3d0075f2011-01-27 10:06:03 +0900483 Define the ETH PHY's address
484
Tom Riniff53ecc2022-12-04 10:13:49 -0500485 CFG_SH_ETHER_CACHE_WRITEBACK
Yoshihiro Shimoda68260aa2011-01-27 10:06:08 +0900486 If this option is set, the driver enables cache flush.
487
Vadim Bendebury5e124722011-10-17 08:36:14 +0000488- TPM Support:
Che-liang Chiou90899cc2013-04-12 11:04:34 +0000489 CONFIG_TPM
490 Support TPM devices.
491
Christophe Ricard0766ad22015-10-06 22:54:41 +0200492 CONFIG_TPM_TIS_INFINEON
493 Support for Infineon i2c bus TPM devices. Only one device
Tom Wai-Hong Tam1b393db2013-04-12 11:04:37 +0000494 per system is supported at this time.
495
Tom Wai-Hong Tam1b393db2013-04-12 11:04:37 +0000496 CONFIG_TPM_TIS_I2C_BURST_LIMITATION
497 Define the burst count bytes upper limit
498
Christophe Ricard3aa74082016-01-21 23:27:13 +0100499 CONFIG_TPM_ST33ZP24
500 Support for STMicroelectronics TPM devices. Requires DM_TPM support.
501
502 CONFIG_TPM_ST33ZP24_I2C
503 Support for STMicroelectronics ST33ZP24 I2C devices.
504 Requires TPM_ST33ZP24 and I2C.
505
Christophe Ricardb75fdc12016-01-21 23:27:14 +0100506 CONFIG_TPM_ST33ZP24_SPI
507 Support for STMicroelectronics ST33ZP24 SPI devices.
508 Requires TPM_ST33ZP24 and SPI.
509
Dirk Eibachc01939c2013-06-26 15:55:15 +0200510 CONFIG_TPM_ATMEL_TWI
511 Support for Atmel TWI TPM device. Requires I2C support.
512
Che-liang Chiou90899cc2013-04-12 11:04:34 +0000513 CONFIG_TPM_TIS_LPC
Vadim Bendebury5e124722011-10-17 08:36:14 +0000514 Support for generic parallel port TPM devices. Only one device
515 per system is supported at this time.
516
Reinhard Pfaube6c1522013-06-26 15:55:13 +0200517 CONFIG_TPM
518 Define this to enable the TPM support library which provides
519 functional interfaces to some TPM commands.
520 Requires support for a TPM device.
521
522 CONFIG_TPM_AUTH_SESSIONS
523 Define this to enable authorized functions in the TPM library.
524 Requires CONFIG_TPM and CONFIG_SHA1.
525
wdenkc6097192002-11-03 00:24:07 +0000526- USB Support:
527 At the moment only the UHCI host controller is
Heiko Schocher064b55c2017-06-14 05:49:40 +0200528 supported (PIP405, MIP405); define
wdenkc6097192002-11-03 00:24:07 +0000529 CONFIG_USB_UHCI to enable it.
530 define CONFIG_USB_KEYBOARD to enable the USB Keyboard
wdenk30d56fa2004-10-09 22:44:59 +0000531 and define CONFIG_USB_STORAGE to enable the USB
wdenkc6097192002-11-03 00:24:07 +0000532 storage devices.
533 Note:
534 Supported are USB Keyboards and USB Floppy drives
535 (TEAC FD-05PUB).
wdenk4d13cba2004-03-14 14:09:05 +0000536
Oleksandr Tymoshenko6e9e0622014-02-01 21:51:25 -0700537 CONFIG_USB_DWC2_REG_ADDR the physical CPU address of the DWC2
538 HW module registers.
539
Wolfgang Denk16c8d5e2006-06-14 17:45:53 +0200540- USB Device:
541 Define the below if you wish to use the USB console.
542 Once firmware is rebuilt from a serial console issue the
543 command "setenv stdin usbtty; setenv stdout usbtty" and
Marcel Ziswiler11ccc332008-07-09 08:17:15 +0200544 attach your USB cable. The Unix command "dmesg" should print
Wolfgang Denk16c8d5e2006-06-14 17:45:53 +0200545 it has found a new device. The environment variable usbtty
546 can be set to gserial or cdc_acm to enable your device to
Wolfgang Denk386eda02006-06-14 18:14:56 +0200547 appear to a USB host as a Linux gserial device or a
Wolfgang Denk16c8d5e2006-06-14 17:45:53 +0200548 Common Device Class Abstract Control Model serial device.
549 If you select usbtty = gserial you should be able to enumerate
550 a Linux host by
551 # modprobe usbserial vendor=0xVendorID product=0xProductID
552 else if using cdc_acm, simply setting the environment
553 variable usbtty to be cdc_acm should suffice. The following
554 might be defined in YourBoardName.h
Wolfgang Denk386eda02006-06-14 18:14:56 +0200555
Wolfgang Denk386eda02006-06-14 18:14:56 +0200556 If you have a USB-IF assigned VendorID then you may wish to
Wolfgang Denk16c8d5e2006-06-14 17:45:53 +0200557 define your own vendor specific values either in BoardName.h
Wolfgang Denk386eda02006-06-14 18:14:56 +0200558 or directly in usbd_vendor_info.h. If you don't define
Wolfgang Denk16c8d5e2006-06-14 17:45:53 +0200559 CONFIG_USBD_MANUFACTURER, CONFIG_USBD_PRODUCT_NAME,
560 CONFIG_USBD_VENDORID and CONFIG_USBD_PRODUCTID, then U-Boot
561 should pretend to be a Linux device to it's target host.
562
563 CONFIG_USBD_MANUFACTURER
564 Define this string as the name of your company for
565 - CONFIG_USBD_MANUFACTURER "my company"
Wolfgang Denk386eda02006-06-14 18:14:56 +0200566
Wolfgang Denk16c8d5e2006-06-14 17:45:53 +0200567 CONFIG_USBD_PRODUCT_NAME
568 Define this string as the name of your product
569 - CONFIG_USBD_PRODUCT_NAME "acme usb device"
570
571 CONFIG_USBD_VENDORID
572 Define this as your assigned Vendor ID from the USB
573 Implementors Forum. This *must* be a genuine Vendor ID
574 to avoid polluting the USB namespace.
575 - CONFIG_USBD_VENDORID 0xFFFF
Wolfgang Denk386eda02006-06-14 18:14:56 +0200576
Wolfgang Denk16c8d5e2006-06-14 17:45:53 +0200577 CONFIG_USBD_PRODUCTID
578 Define this as the unique Product ID
579 for your device
580 - CONFIG_USBD_PRODUCTID 0xFFFF
wdenkc6097192002-11-03 00:24:07 +0000581
Igor Grinbergd70a5602011-12-12 12:08:35 +0200582- ULPI Layer Support:
583 The ULPI (UTMI Low Pin (count) Interface) PHYs are supported via
584 the generic ULPI layer. The generic layer accesses the ULPI PHY
585 via the platform viewport, so you need both the genric layer and
586 the viewport enabled. Currently only Chipidea/ARC based
587 viewport is supported.
588 To enable the ULPI layer support, define CONFIG_USB_ULPI and
589 CONFIG_USB_ULPI_VIEWPORT in your board configuration file.
Lucas Stach6d365ea2012-10-01 00:44:35 +0200590 If your ULPI phy needs a different reference clock than the
Tom Rini6e7df1d2023-01-10 11:19:45 -0500591 standard 24 MHz then you have to define CFG_ULPI_REF_CLK to
Lucas Stach6d365ea2012-10-01 00:44:35 +0200592 the appropriate value in Hz.
wdenkc6097192002-11-03 00:24:07 +0000593
594- MMC Support:
Yoshihiro Shimodaafb35662011-07-04 22:21:22 +0000595 CONFIG_SH_MMCIF
596 Support for Renesas on-chip MMCIF controller
597
598 CONFIG_SH_MMCIF_ADDR
599 Define the base address of MMCIF registers
600
601 CONFIG_SH_MMCIF_CLK
602 Define the clock frequency for MMCIF
603
Tom Rinib3ba6e92013-03-14 05:32:47 +0000604- USB Device Firmware Update (DFU) class support:
Marek Vasutbb4059a2018-02-16 16:41:18 +0100605 CONFIG_DFU_OVER_USB
Tom Rinib3ba6e92013-03-14 05:32:47 +0000606 This enables the USB portion of the DFU USB class
607
Pantelis Antoniouc6631762013-03-14 05:32:52 +0000608 CONFIG_DFU_NAND
609 This enables support for exposing NAND devices via DFU.
610
Afzal Mohammeda9479f02013-09-18 01:15:24 +0530611 CONFIG_DFU_RAM
612 This enables support for exposing RAM via DFU.
613 Note: DFU spec refer to non-volatile memory usage, but
614 allow usages beyond the scope of spec - here RAM usage,
615 one that would help mostly the developer.
616
Heiko Schochere7e75c72013-06-12 06:05:51 +0200617 CONFIG_SYS_DFU_DATA_BUF_SIZE
618 Dfu transfer uses a buffer before writing data to the
619 raw storage device. Make the size (in bytes) of this buffer
620 configurable. The size of this buffer is also configurable
621 through the "dfu_bufsiz" environment variable.
622
Pantelis Antoniouea2453d2013-03-14 05:32:48 +0000623 CONFIG_SYS_DFU_MAX_FILE_SIZE
624 When updating files rather than the raw storage device,
625 we use a static buffer to copy the file into and then write
626 the buffer once we've been given the whole file. Define
627 this to the maximum filesize (in bytes) for the buffer.
628 Default is 4 MiB if undefined.
629
Heiko Schocher001a8312014-03-18 08:09:56 +0100630 DFU_DEFAULT_POLL_TIMEOUT
631 Poll timeout [ms], is the timeout a device can send to the
632 host. The host must wait for this timeout before sending
633 a subsequent DFU_GET_STATUS request to the device.
634
635 DFU_MANIFEST_POLL_TIMEOUT
636 Poll timeout [ms], which the device sends to the host when
637 entering dfuMANIFEST state. Host waits this timeout, before
638 sending again an USB request to the device.
639
wdenkc6097192002-11-03 00:24:07 +0000640- Keyboard Support:
Simon Glass39f615e2015-11-11 10:05:47 -0700641 See Kconfig help for available keyboard drivers.
642
wdenk17ea1172004-06-06 21:51:03 +0000643- MII/PHY support:
wdenk17ea1172004-06-06 21:51:03 +0000644 CONFIG_PHY_CLOCK_FREQ (ppc4xx)
645
646 The clock frequency of the MII bus
647
wdenk17ea1172004-06-06 21:51:03 +0000648 CONFIG_PHY_CMD_DELAY (ppc4xx)
649
650 Some PHY like Intel LXT971A need extra delay after
651 command issued before MII status register can be read
652
wdenkc6097192002-11-03 00:24:07 +0000653- BOOTP Recovery Mode:
654 CONFIG_BOOTP_RANDOM_DELAY
655
656 If you have many targets in a network that try to
657 boot using BOOTP, you may want to avoid that all
658 systems send out BOOTP requests at precisely the same
659 moment (which would happen for instance at recovery
660 from a power failure, when all systems will try to
661 boot, thus flooding the BOOTP server. Defining
662 CONFIG_BOOTP_RANDOM_DELAY causes a random delay to be
663 inserted before sending out BOOTP requests. The
Wolfgang Denk6c33c782007-08-06 23:21:05 +0200664 following delays are inserted then:
wdenkc6097192002-11-03 00:24:07 +0000665
666 1st BOOTP request: delay 0 ... 1 sec
667 2nd BOOTP request: delay 0 ... 2 sec
668 3rd BOOTP request: delay 0 ... 4 sec
669 4th and following
670 BOOTP requests: delay 0 ... 8 sec
671
Tom Rini6e7df1d2023-01-10 11:19:45 -0500672 CFG_BOOTP_ID_CACHE_SIZE
Thierry Reding92ac8ac2014-08-19 10:21:24 +0200673
674 BOOTP packets are uniquely identified using a 32-bit ID. The
675 server will copy the ID from client requests to responses and
676 U-Boot will use this to determine if it is the destination of
677 an incoming response. Some servers will check that addresses
678 aren't in use before handing them out (usually using an ARP
679 ping) and therefore take up to a few hundred milliseconds to
680 respond. Network congestion may also influence the time it
681 takes for a response to make it back to the client. If that
682 time is too long, U-Boot will retransmit requests. In order
683 to allow earlier responses to still be accepted after these
684 retransmissions, U-Boot's BOOTP client keeps a small cache of
Tom Rini6e7df1d2023-01-10 11:19:45 -0500685 IDs. The CFG_BOOTP_ID_CACHE_SIZE controls the size of this
Thierry Reding92ac8ac2014-08-19 10:21:24 +0200686 cache. The default is to keep IDs for up to four outstanding
687 requests. Increasing this will allow U-Boot to accept offers
688 from a BOOTP client in networks with unusually high latency.
689
stroesefe389a82003-08-28 14:17:32 +0000690- DHCP Advanced Options:
Joe Hershberger2c00e092012-05-23 07:59:19 +0000691
Joe Hershbergerd22c3382012-05-23 08:00:12 +0000692 - Link-local IP address negotiation:
693 Negotiate with other link-local clients on the local network
694 for an address that doesn't require explicit configuration.
695 This is especially useful if a DHCP server cannot be guaranteed
696 to exist in all environments that the device must operate.
697
698 See doc/README.link-local for more information.
699
Prabhakar Kushwaha24acb832017-11-23 16:51:32 +0530700 - MAC address from environment variables
701
702 FDT_SEQ_MACADDR_FROM_ENV
703
704 Fix-up device tree with MAC addresses fetched sequentially from
705 environment variables. This config work on assumption that
706 non-usable ethernet node of device-tree are either not present
707 or their status has been marked as "disabled".
708
wdenka3d991b2004-04-15 21:48:45 +0000709 - CDP Options:
wdenk6e592382004-04-18 17:39:38 +0000710 CONFIG_CDP_DEVICE_ID
wdenka3d991b2004-04-15 21:48:45 +0000711
712 The device id used in CDP trigger frames.
713
714 CONFIG_CDP_DEVICE_ID_PREFIX
715
716 A two character string which is prefixed to the MAC address
717 of the device.
718
719 CONFIG_CDP_PORT_ID
720
721 A printf format string which contains the ascii name of
722 the port. Normally is set to "eth%d" which sets
Marcel Ziswiler11ccc332008-07-09 08:17:15 +0200723 eth0 for the first Ethernet, eth1 for the second etc.
wdenka3d991b2004-04-15 21:48:45 +0000724
725 CONFIG_CDP_CAPABILITIES
726
727 A 32bit integer which indicates the device capabilities;
728 0x00000010 for a normal host which does not forwards.
729
730 CONFIG_CDP_VERSION
731
732 An ascii string containing the version of the software.
733
734 CONFIG_CDP_PLATFORM
735
736 An ascii string containing the name of the platform.
737
738 CONFIG_CDP_TRIGGER
739
740 A 32bit integer sent on the trigger.
741
742 CONFIG_CDP_POWER_CONSUMPTION
743
744 A 16bit integer containing the power consumption of the
745 device in .1 of milliwatts.
746
747 CONFIG_CDP_APPLIANCE_VLAN_TYPE
748
749 A byte containing the id of the VLAN.
750
Uri Mashiach79267ed2017-01-19 10:51:05 +0200751- Status LED: CONFIG_LED_STATUS
wdenkc6097192002-11-03 00:24:07 +0000752
753 Several configurations allow to display the current
754 status using a LED. For instance, the LED will blink
755 fast while running U-Boot code, stop blinking as
756 soon as a reply to a BOOTP request was received, and
757 start blinking slow once the Linux kernel is running
758 (supported by a status LED driver in the Linux
Uri Mashiach79267ed2017-01-19 10:51:05 +0200759 kernel). Defining CONFIG_LED_STATUS enables this
wdenkc6097192002-11-03 00:24:07 +0000760 feature in U-Boot.
761
Igor Grinberg1df7bbb2013-11-08 01:03:50 +0200762 Additional options:
763
Uri Mashiach79267ed2017-01-19 10:51:05 +0200764 CONFIG_LED_STATUS_GPIO
Igor Grinberg1df7bbb2013-11-08 01:03:50 +0200765 The status LED can be connected to a GPIO pin.
766 In such cases, the gpio_led driver can be used as a
Uri Mashiach79267ed2017-01-19 10:51:05 +0200767 status LED backend implementation. Define CONFIG_LED_STATUS_GPIO
Igor Grinberg1df7bbb2013-11-08 01:03:50 +0200768 to include the gpio_led driver in the U-Boot binary.
769
Tom Rini6e7df1d2023-01-10 11:19:45 -0500770 CFG_GPIO_LED_INVERTED_TABLE
Igor Grinberg9dfdcdf2013-11-08 01:03:52 +0200771 Some GPIO connected LEDs may have inverted polarity in which
772 case the GPIO high value corresponds to LED off state and
773 GPIO low value corresponds to LED on state.
Tom Rini6e7df1d2023-01-10 11:19:45 -0500774 In such cases CFG_GPIO_LED_INVERTED_TABLE may be defined
Igor Grinberg9dfdcdf2013-11-08 01:03:52 +0200775 with a list of GPIO LEDs that have inverted polarity.
776
Tom Rini55dabcc2021-08-18 23:12:24 -0400777- I2C Support:
Tom Rinicdc5ed82022-11-16 13:10:29 -0500778 CFG_SYS_NUM_I2C_BUSES
Simon Glass945a18e2016-10-02 18:01:05 -0600779 Hold the number of i2c buses you want to use.
Heiko Schocher3f4978c2012-01-16 21:12:24 +0000780
Tom Rinid8964b32022-12-04 10:13:57 -0500781 CFG_SYS_I2C_DIRECT_BUS
Heiko Schocher3f4978c2012-01-16 21:12:24 +0000782 define this, if you don't use i2c muxes on your hardware.
Tom Rini65cc0e22022-11-16 13:10:41 -0500783 if CFG_SYS_I2C_MAX_HOPS is not defined or == 0 you can
Heiko Schocher3f4978c2012-01-16 21:12:24 +0000784 omit this define.
785
Tom Rini65cc0e22022-11-16 13:10:41 -0500786 CFG_SYS_I2C_MAX_HOPS
Heiko Schocher3f4978c2012-01-16 21:12:24 +0000787 define how many muxes are maximal consecutively connected
788 on one i2c bus. If you not use i2c muxes, omit this
789 define.
790
Tom Rini65cc0e22022-11-16 13:10:41 -0500791 CFG_SYS_I2C_BUSES
Jeremiah Mahlerb445bbb2015-01-04 18:56:50 -0800792 hold a list of buses you want to use, only used if
Tom Rinid8964b32022-12-04 10:13:57 -0500793 CFG_SYS_I2C_DIRECT_BUS is not defined, for example
Tom Rini65cc0e22022-11-16 13:10:41 -0500794 a board with CFG_SYS_I2C_MAX_HOPS = 1 and
Tom Rinicdc5ed82022-11-16 13:10:29 -0500795 CFG_SYS_NUM_I2C_BUSES = 9:
Heiko Schocher3f4978c2012-01-16 21:12:24 +0000796
Tom Rini65cc0e22022-11-16 13:10:41 -0500797 CFG_SYS_I2C_BUSES {{0, {I2C_NULL_HOP}}, \
Heiko Schocher3f4978c2012-01-16 21:12:24 +0000798 {0, {{I2C_MUX_PCA9547, 0x70, 1}}}, \
799 {0, {{I2C_MUX_PCA9547, 0x70, 2}}}, \
800 {0, {{I2C_MUX_PCA9547, 0x70, 3}}}, \
801 {0, {{I2C_MUX_PCA9547, 0x70, 4}}}, \
802 {0, {{I2C_MUX_PCA9547, 0x70, 5}}}, \
803 {1, {I2C_NULL_HOP}}, \
804 {1, {{I2C_MUX_PCA9544, 0x72, 1}}}, \
805 {1, {{I2C_MUX_PCA9544, 0x72, 2}}}, \
806 }
807
808 which defines
809 bus 0 on adapter 0 without a mux
Heiko Schocherea818db2013-01-29 08:53:15 +0100810 bus 1 on adapter 0 with a PCA9547 on address 0x70 port 1
811 bus 2 on adapter 0 with a PCA9547 on address 0x70 port 2
812 bus 3 on adapter 0 with a PCA9547 on address 0x70 port 3
813 bus 4 on adapter 0 with a PCA9547 on address 0x70 port 4
814 bus 5 on adapter 0 with a PCA9547 on address 0x70 port 5
Heiko Schocher3f4978c2012-01-16 21:12:24 +0000815 bus 6 on adapter 1 without a mux
Heiko Schocherea818db2013-01-29 08:53:15 +0100816 bus 7 on adapter 1 with a PCA9544 on address 0x72 port 1
817 bus 8 on adapter 1 with a PCA9544 on address 0x72 port 2
Heiko Schocher3f4978c2012-01-16 21:12:24 +0000818
819 If you do not have i2c muxes on your board, omit this define.
820
Simon Glassce3b5d62017-05-12 21:10:00 -0600821- Legacy I2C Support:
Heiko Schocherea818db2013-01-29 08:53:15 +0100822 If you use the software i2c interface (CONFIG_SYS_I2C_SOFT)
wdenkb37c7e52003-06-30 16:24:52 +0000823 then the following macros need to be defined (examples are
824 from include/configs/lwmon.h):
wdenkc6097192002-11-03 00:24:07 +0000825
826 I2C_INIT
827
wdenkb37c7e52003-06-30 16:24:52 +0000828 (Optional). Any commands necessary to enable the I2C
wdenk43d96162003-03-06 00:02:04 +0000829 controller or configure ports.
wdenkc6097192002-11-03 00:24:07 +0000830
wdenkba56f622004-02-06 23:19:44 +0000831 eg: #define I2C_INIT (immr->im_cpm.cp_pbdir |= PB_SCL)
wdenkb37c7e52003-06-30 16:24:52 +0000832
wdenkc6097192002-11-03 00:24:07 +0000833 I2C_ACTIVE
834
835 The code necessary to make the I2C data line active
836 (driven). If the data line is open collector, this
837 define can be null.
838
wdenkb37c7e52003-06-30 16:24:52 +0000839 eg: #define I2C_ACTIVE (immr->im_cpm.cp_pbdir |= PB_SDA)
840
wdenkc6097192002-11-03 00:24:07 +0000841 I2C_TRISTATE
842
843 The code necessary to make the I2C data line tri-stated
844 (inactive). If the data line is open collector, this
845 define can be null.
846
wdenkb37c7e52003-06-30 16:24:52 +0000847 eg: #define I2C_TRISTATE (immr->im_cpm.cp_pbdir &= ~PB_SDA)
848
wdenkc6097192002-11-03 00:24:07 +0000849 I2C_READ
850
York Sun472d5462013-04-01 11:29:11 -0700851 Code that returns true if the I2C data line is high,
852 false if it is low.
wdenkc6097192002-11-03 00:24:07 +0000853
wdenkb37c7e52003-06-30 16:24:52 +0000854 eg: #define I2C_READ ((immr->im_cpm.cp_pbdat & PB_SDA) != 0)
855
wdenkc6097192002-11-03 00:24:07 +0000856 I2C_SDA(bit)
857
York Sun472d5462013-04-01 11:29:11 -0700858 If <bit> is true, sets the I2C data line high. If it
859 is false, it clears it (low).
wdenkc6097192002-11-03 00:24:07 +0000860
wdenkb37c7e52003-06-30 16:24:52 +0000861 eg: #define I2C_SDA(bit) \
wdenk2535d602003-07-17 23:16:40 +0000862 if(bit) immr->im_cpm.cp_pbdat |= PB_SDA; \
wdenkba56f622004-02-06 23:19:44 +0000863 else immr->im_cpm.cp_pbdat &= ~PB_SDA
wdenkb37c7e52003-06-30 16:24:52 +0000864
wdenkc6097192002-11-03 00:24:07 +0000865 I2C_SCL(bit)
866
York Sun472d5462013-04-01 11:29:11 -0700867 If <bit> is true, sets the I2C clock line high. If it
868 is false, it clears it (low).
wdenkc6097192002-11-03 00:24:07 +0000869
wdenkb37c7e52003-06-30 16:24:52 +0000870 eg: #define I2C_SCL(bit) \
wdenk2535d602003-07-17 23:16:40 +0000871 if(bit) immr->im_cpm.cp_pbdat |= PB_SCL; \
wdenkba56f622004-02-06 23:19:44 +0000872 else immr->im_cpm.cp_pbdat &= ~PB_SCL
wdenkb37c7e52003-06-30 16:24:52 +0000873
wdenkc6097192002-11-03 00:24:07 +0000874 I2C_DELAY
875
876 This delay is invoked four times per clock cycle so this
877 controls the rate of data transfer. The data rate thus
wdenkb37c7e52003-06-30 16:24:52 +0000878 is 1 / (I2C_DELAY * 4). Often defined to be something
wdenk945af8d2003-07-16 21:53:01 +0000879 like:
880
wdenkb37c7e52003-06-30 16:24:52 +0000881 #define I2C_DELAY udelay(2)
wdenkc6097192002-11-03 00:24:07 +0000882
Mike Frysinger793b5722010-07-21 13:38:02 -0400883 CONFIG_SOFT_I2C_GPIO_SCL / CONFIG_SOFT_I2C_GPIO_SDA
884
885 If your arch supports the generic GPIO framework (asm/gpio.h),
886 then you may alternatively define the two GPIOs that are to be
887 used as SCL / SDA. Any of the previous I2C_xxx macros will
888 have GPIO-based defaults assigned to them as appropriate.
889
890 You should define these to the GPIO value as given directly to
891 the generic GPIO functions.
892
Tom Rinie06b9b82022-12-04 10:04:08 -0500893 CFG_I2C_MULTI_BUS
Ben Warrenbb99ad62006-09-07 16:50:54 -0400894
895 This option allows the use of multiple I2C buses, each of which
Wolfgang Denkc0f40852011-10-26 10:21:21 +0000896 must have a controller. At any point in time, only one bus is
897 active. To switch to a different bus, use the 'i2c dev' command.
Ben Warrenbb99ad62006-09-07 16:50:54 -0400898 Note that bus numbering is zero-based.
899
Tom Rini65cc0e22022-11-16 13:10:41 -0500900 CFG_SYS_I2C_NOPROBES
Ben Warrenbb99ad62006-09-07 16:50:54 -0400901
902 This option specifies a list of I2C devices that will be skipped
Tom Rini1353b252022-12-02 16:42:30 -0500903 when the 'i2c probe' command is issued.
Ben Warrenbb99ad62006-09-07 16:50:54 -0400904
905 e.g.
Tom Rini65cc0e22022-11-16 13:10:41 -0500906 #define CFG_SYS_I2C_NOPROBES {0x50,0x68}
Ben Warrenbb99ad62006-09-07 16:50:54 -0400907
908 will skip addresses 0x50 and 0x68 on a board with one I2C bus
909
Tom Rini65cc0e22022-11-16 13:10:41 -0500910 CFG_SYS_RTC_BUS_NUM
Stefan Roese0dc018e2007-02-20 10:51:26 +0100911
912 If defined, then this indicates the I2C bus number for the RTC.
913 If not defined, then U-Boot assumes that RTC is on I2C bus 0.
914
Andrew Dyer2ac69852008-12-29 17:36:01 -0600915 CONFIG_SOFT_I2C_READ_REPEATED_START
916
917 defining this will force the i2c_read() function in
918 the soft_i2c driver to perform an I2C repeated start
919 between writing the address pointer and reading the
920 data. If this define is omitted the default behaviour
921 of doing a stop-start sequence will be used. Most I2C
922 devices can use either method, but some require one or
923 the other.
Timur Tabibe5e6182006-11-03 19:15:00 -0600924
wdenkc6097192002-11-03 00:24:07 +0000925- SPI Support: CONFIG_SPI
926
927 Enables SPI driver (so far only tested with
928 SPI EEPROM, also an instance works with Crystal A/D and
929 D/As on the SACSng board)
930
Tom Rini6e7df1d2023-01-10 11:19:45 -0500931 CFG_SYS_SPI_MXC_WAIT
Heiko Schocherf659b572014-07-14 10:22:11 +0200932 Timeout for waiting until spi transfer completed.
933 default: (CONFIG_SYS_HZ/100) /* 10 ms */
934
Matthias Fuchs01335022007-12-27 17:12:34 +0100935- FPGA Support: CONFIG_FPGA
936
937 Enables FPGA subsystem.
938
939 CONFIG_FPGA_<vendor>
940
941 Enables support for specific chip vendors.
942 (ALTERA, XILINX)
943
944 CONFIG_FPGA_<family>
945
946 Enables support for FPGA family.
947 (SPARTAN2, SPARTAN3, VIRTEX2, CYCLONE2, ACEX1K, ACEX)
948
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +0200949 CONFIG_SYS_FPGA_CHECK_BUSY
wdenkc6097192002-11-03 00:24:07 +0000950
wdenk43d96162003-03-06 00:02:04 +0000951 Enable checks on FPGA configuration interface busy
952 status by the configuration function. This option
953 will require a board or device specific function to
954 be written.
wdenkc6097192002-11-03 00:24:07 +0000955
Tom Rini72fc2642022-12-04 10:03:57 -0500956 CFG_FPGA_DELAY
wdenkc6097192002-11-03 00:24:07 +0000957
958 If defined, a function that provides delays in the FPGA
959 configuration driver.
960
Tom Rini6e7df1d2023-01-10 11:19:45 -0500961 CFG_SYS_FPGA_CHECK_ERROR
wdenkc6097192002-11-03 00:24:07 +0000962
wdenk43d96162003-03-06 00:02:04 +0000963 Check for configuration errors during FPGA bitfile
964 loading. For example, abort during Virtex II
965 configuration if the INIT_B line goes low (which
966 indicated a CRC error).
wdenkc6097192002-11-03 00:24:07 +0000967
Tom Rini65cc0e22022-11-16 13:10:41 -0500968 CFG_SYS_FPGA_WAIT_INIT
wdenkc6097192002-11-03 00:24:07 +0000969
Jeremiah Mahlerb445bbb2015-01-04 18:56:50 -0800970 Maximum time to wait for the INIT_B line to de-assert
971 after PROB_B has been de-asserted during a Virtex II
wdenk43d96162003-03-06 00:02:04 +0000972 FPGA configuration sequence. The default time is 500
Marcel Ziswiler11ccc332008-07-09 08:17:15 +0200973 ms.
wdenkc6097192002-11-03 00:24:07 +0000974
Tom Rini65cc0e22022-11-16 13:10:41 -0500975 CFG_SYS_FPGA_WAIT_BUSY
wdenkc6097192002-11-03 00:24:07 +0000976
Jeremiah Mahlerb445bbb2015-01-04 18:56:50 -0800977 Maximum time to wait for BUSY to de-assert during
Marcel Ziswiler11ccc332008-07-09 08:17:15 +0200978 Virtex II FPGA configuration. The default is 5 ms.
wdenkc6097192002-11-03 00:24:07 +0000979
Tom Rini65cc0e22022-11-16 13:10:41 -0500980 CFG_SYS_FPGA_WAIT_CONFIG
wdenkc6097192002-11-03 00:24:07 +0000981
wdenk43d96162003-03-06 00:02:04 +0000982 Time to wait after FPGA configuration. The default is
Marcel Ziswiler11ccc332008-07-09 08:17:15 +0200983 200 ms.
wdenkc6097192002-11-03 00:24:07 +0000984
wdenkc6097192002-11-03 00:24:07 +0000985- Vendor Parameter Protection:
986
wdenk43d96162003-03-06 00:02:04 +0000987 U-Boot considers the values of the environment
988 variables "serial#" (Board Serial Number) and
wdenk7152b1d2003-09-05 23:19:14 +0000989 "ethaddr" (Ethernet Address) to be parameters that
wdenk43d96162003-03-06 00:02:04 +0000990 are set once by the board vendor / manufacturer, and
991 protects these variables from casual modification by
992 the user. Once set, these variables are read-only,
993 and write or delete attempts are rejected. You can
Marcel Ziswiler11ccc332008-07-09 08:17:15 +0200994 change this behaviour:
wdenkc6097192002-11-03 00:24:07 +0000995
996 If CONFIG_ENV_OVERWRITE is #defined in your config
997 file, the write protection for vendor parameters is
wdenk47cd00f2003-03-06 13:39:27 +0000998 completely disabled. Anybody can change or delete
wdenkc6097192002-11-03 00:24:07 +0000999 these parameters.
1000
Joe Hershberger25980902012-12-11 22:16:31 -06001001 The same can be accomplished in a more flexible way
1002 for any variable by configuring the type of access
1003 to allow for those variables in the ".flags" variable
Tom Riniacf29d82022-12-04 10:03:40 -05001004 or define CFG_ENV_FLAGS_LIST_STATIC.
Joe Hershberger25980902012-12-11 22:16:31 -06001005
wdenkc6097192002-11-03 00:24:07 +00001006- Protected RAM:
Tom Rini7c5c1372022-12-04 10:13:37 -05001007 CFG_PRAM
wdenkc6097192002-11-03 00:24:07 +00001008
1009 Define this variable to enable the reservation of
1010 "protected RAM", i. e. RAM which is not overwritten
Tom Rini7c5c1372022-12-04 10:13:37 -05001011 by U-Boot. Define CFG_PRAM to hold the number of
wdenkc6097192002-11-03 00:24:07 +00001012 kB you want to reserve for pRAM. You can overwrite
1013 this default value by defining an environment
1014 variable "pram" to the number of kB you want to
1015 reserve. Note that the board info structure will
1016 still show the full amount of RAM. If pRAM is
1017 reserved, a new environment variable "mem" will
1018 automatically be defined to hold the amount of
1019 remaining RAM in a form that can be passed as boot
1020 argument to Linux, for instance like that:
1021
Wolfgang Denkfe126d82005-11-20 21:40:11 +01001022 setenv bootargs ... mem=\${mem}
wdenkc6097192002-11-03 00:24:07 +00001023 saveenv
1024
1025 This way you can tell Linux not to use this memory,
1026 either, which results in a memory region that will
1027 not be affected by reboots.
1028
1029 *WARNING* If your board configuration uses automatic
1030 detection of the RAM size, you must make sure that
1031 this memory test is non-destructive. So far, the
1032 following board configurations are known to be
1033 "pRAM-clean":
1034
Heiko Schocher5b8e76c2017-06-07 17:33:09 +02001035 IVMS8, IVML24, SPD8xx,
Wolfgang Denk1b0757e2012-10-24 02:36:15 +00001036 HERMES, IP860, RPXlite, LWMON,
Heiko Schocher2eb48ff2017-06-07 17:33:10 +02001037 FLAGADM
wdenkc6097192002-11-03 00:24:07 +00001038
1039- Error Recovery:
wdenkc6097192002-11-03 00:24:07 +00001040 Note:
1041
wdenk8bde7f72003-06-27 21:31:46 +00001042 In the current implementation, the local variables
1043 space and global environment variables space are
1044 separated. Local variables are those you define by
1045 simply typing `name=value'. To access a local
1046 variable later on, you have write `$name' or
1047 `${name}'; to execute the contents of a variable
1048 directly type `$name' at the command prompt.
wdenkc6097192002-11-03 00:24:07 +00001049
wdenk43d96162003-03-06 00:02:04 +00001050 Global environment variables are those you use
1051 setenv/printenv to work with. To run a command stored
1052 in such a variable, you need to use the run command,
1053 and you must not use the '$' sign to access them.
wdenkc6097192002-11-03 00:24:07 +00001054
1055 To store commands and special characters in a
1056 variable, please use double quotation marks
1057 surrounding the whole text of the variable, instead
1058 of the backslashes before semicolons and special
1059 symbols.
1060
wdenka8c7c702003-12-06 19:49:23 +00001061- Default Environment:
Tom Rini0613c362022-12-04 10:03:50 -05001062 CFG_EXTRA_ENV_SETTINGS
wdenkc6097192002-11-03 00:24:07 +00001063
wdenk43d96162003-03-06 00:02:04 +00001064 Define this to contain any number of null terminated
1065 strings (variable = value pairs) that will be part of
wdenk7152b1d2003-09-05 23:19:14 +00001066 the default environment compiled into the boot image.
wdenk2262cfe2002-11-18 00:14:45 +00001067
wdenk43d96162003-03-06 00:02:04 +00001068 For example, place something like this in your
1069 board's config file:
wdenkc6097192002-11-03 00:24:07 +00001070
Tom Rini0613c362022-12-04 10:03:50 -05001071 #define CFG_EXTRA_ENV_SETTINGS \
wdenkc6097192002-11-03 00:24:07 +00001072 "myvar1=value1\0" \
1073 "myvar2=value2\0"
1074
wdenk43d96162003-03-06 00:02:04 +00001075 Warning: This method is based on knowledge about the
1076 internal format how the environment is stored by the
1077 U-Boot code. This is NOT an official, exported
1078 interface! Although it is unlikely that this format
wdenk7152b1d2003-09-05 23:19:14 +00001079 will change soon, there is no guarantee either.
wdenkc6097192002-11-03 00:24:07 +00001080 You better know what you are doing here.
1081
wdenk43d96162003-03-06 00:02:04 +00001082 Note: overly (ab)use of the default environment is
1083 discouraged. Make sure to check other ways to preset
Wolfgang Denk74de7ae2009-04-01 23:34:12 +02001084 the environment like the "source" command or the
wdenk43d96162003-03-06 00:02:04 +00001085 boot command first.
wdenkc6097192002-11-03 00:24:07 +00001086
Simon Glass06fd8532012-11-30 13:01:17 +00001087 CONFIG_DELAY_ENVIRONMENT
1088
1089 Normally the environment is loaded when the board is
Jeremiah Mahlerb445bbb2015-01-04 18:56:50 -08001090 initialised so that it is available to U-Boot. This inhibits
Simon Glass06fd8532012-11-30 13:01:17 +00001091 that so that the environment is not available until
1092 explicitly loaded later by U-Boot code. With CONFIG_OF_CONTROL
1093 this is instead controlled by the value of
1094 /config/load-environment.
1095
Detlev Zundelcccfc2a2009-12-01 17:16:19 +01001096- Automatic software updates via TFTP server
1097 CONFIG_UPDATE_TFTP
1098 CONFIG_UPDATE_TFTP_CNT_MAX
1099 CONFIG_UPDATE_TFTP_MSEC_MAX
1100
1101 These options enable and control the auto-update feature;
1102 for a more detailed description refer to doc/README.update.
1103
1104- MTD Support (mtdparts command, UBI support)
Heiko Schocherff94bc42014-06-24 10:10:04 +02001105 CONFIG_MTD_UBI_WL_THRESHOLD
1106 This parameter defines the maximum difference between the highest
1107 erase counter value and the lowest erase counter value of eraseblocks
1108 of UBI devices. When this threshold is exceeded, UBI starts performing
1109 wear leveling by means of moving data from eraseblock with low erase
1110 counter to eraseblocks with high erase counter.
1111
1112 The default value should be OK for SLC NAND flashes, NOR flashes and
1113 other flashes which have eraseblock life-cycle 100000 or more.
1114 However, in case of MLC NAND flashes which typically have eraseblock
1115 life-cycle less than 10000, the threshold should be lessened (e.g.,
1116 to 128 or 256, although it does not have to be power of 2).
1117
1118 default: 4096
Simon Glassc654b512014-10-23 18:58:54 -06001119
Heiko Schocherff94bc42014-06-24 10:10:04 +02001120 CONFIG_MTD_UBI_BEB_LIMIT
1121 This option specifies the maximum bad physical eraseblocks UBI
1122 expects on the MTD device (per 1024 eraseblocks). If the
1123 underlying flash does not admit of bad eraseblocks (e.g. NOR
1124 flash), this value is ignored.
1125
1126 NAND datasheets often specify the minimum and maximum NVM
1127 (Number of Valid Blocks) for the flashes' endurance lifetime.
1128 The maximum expected bad eraseblocks per 1024 eraseblocks
1129 then can be calculated as "1024 * (1 - MinNVB / MaxNVB)",
1130 which gives 20 for most NANDs (MaxNVB is basically the total
1131 count of eraseblocks on the chip).
1132
1133 To put it differently, if this value is 20, UBI will try to
1134 reserve about 1.9% of physical eraseblocks for bad blocks
1135 handling. And that will be 1.9% of eraseblocks on the entire
1136 NAND chip, not just the MTD partition UBI attaches. This means
1137 that if you have, say, a NAND flash chip admits maximum 40 bad
1138 eraseblocks, and it is split on two MTD partitions of the same
1139 size, UBI will reserve 40 eraseblocks when attaching a
1140 partition.
1141
1142 default: 20
1143
1144 CONFIG_MTD_UBI_FASTMAP
1145 Fastmap is a mechanism which allows attaching an UBI device
1146 in nearly constant time. Instead of scanning the whole MTD device it
1147 only has to locate a checkpoint (called fastmap) on the device.
1148 The on-flash fastmap contains all information needed to attach
1149 the device. Using fastmap makes only sense on large devices where
1150 attaching by scanning takes long. UBI will not automatically install
1151 a fastmap on old images, but you can set the UBI parameter
1152 CONFIG_MTD_UBI_FASTMAP_AUTOCONVERT to 1 if you want so. Please note
1153 that fastmap-enabled images are still usable with UBI implementations
1154 without fastmap support. On typical flash devices the whole fastmap
1155 fits into one PEB. UBI will reserve PEBs to hold two fastmaps.
1156
1157 CONFIG_MTD_UBI_FASTMAP_AUTOCONVERT
1158 Set this parameter to enable fastmap automatically on images
1159 without a fastmap.
1160 default: 0
1161
Heiko Schocher0195a7b2015-10-22 06:19:21 +02001162 CONFIG_MTD_UBI_FM_DEBUG
1163 Enable UBI fastmap debug
1164 default: 0
1165
Daniel Schwierzeck6a11cf42011-07-18 07:48:07 +00001166- SPL framework
Wolfgang Denk04e5ae72011-09-11 21:24:09 +02001167 CONFIG_SPL
1168 Enable building of SPL globally.
Daniel Schwierzeck6a11cf42011-07-18 07:48:07 +00001169
Albert ARIBAUD \(3ADEV\)8c80eb32015-03-31 11:40:50 +02001170 CONFIG_SPL_PANIC_ON_RAW_IMAGE
1171 When defined, SPL will panic() if the image it has
1172 loaded does not have a signature.
1173 Defining this is useful when code which loads images
1174 in SPL cannot guarantee that absolutely all read errors
1175 will be caught.
1176 An example is the LPC32XX MLC NAND driver, which will
1177 consider that a completely unreadable NAND block is bad,
1178 and thus should be skipped silently.
1179
Tom Rini861a86f2012-08-13 11:37:56 -07001180 CONFIG_SPL_DISPLAY_PRINT
1181 For ARM, enable an optional function to print more information
1182 about the running system.
1183
Scott Wood06f60ae2012-12-06 13:33:17 +00001184 CONFIG_SPL_MPC83XX_WAIT_FOR_NAND
1185 Set this for NAND SPL on PPC mpc83xx targets, so that
1186 start.S waits for the rest of the SPL to load before
1187 continuing (the hardware starts execution after just
1188 loading the first page rather than the full 4K).
1189
Thomas Gleixner6f4e7d32016-07-12 20:28:12 +02001190 CONFIG_SPL_UBI
1191 Support for a lightweight UBI (fastmap) scanner and
1192 loader
1193
Tom Rini95579792012-02-14 07:29:40 +00001194 CONFIG_SYS_NAND_5_ADDR_CYCLE, CONFIG_SYS_NAND_PAGE_COUNT,
1195 CONFIG_SYS_NAND_PAGE_SIZE, CONFIG_SYS_NAND_OOBSIZE,
1196 CONFIG_SYS_NAND_BLOCK_SIZE, CONFIG_SYS_NAND_BAD_BLOCK_POS,
Tom Rini4e590942022-11-12 17:36:51 -05001197 CFG_SYS_NAND_ECCPOS, CFG_SYS_NAND_ECCSIZE,
1198 CFG_SYS_NAND_ECCBYTES
Tom Rini95579792012-02-14 07:29:40 +00001199 Defines the size and behavior of the NAND that SPL uses
Scott Wood7d4b7952012-09-21 18:35:27 -05001200 to read U-Boot
Tom Rini95579792012-02-14 07:29:40 +00001201
Tom Rini4e590942022-11-12 17:36:51 -05001202 CFG_SYS_NAND_U_BOOT_DST
Scott Wood7d4b7952012-09-21 18:35:27 -05001203 Location in memory to load U-Boot to
1204
Tom Rini4e590942022-11-12 17:36:51 -05001205 CFG_SYS_NAND_U_BOOT_SIZE
Scott Wood7d4b7952012-09-21 18:35:27 -05001206 Size of image to load
Tom Rini95579792012-02-14 07:29:40 +00001207
Tom Rini4e590942022-11-12 17:36:51 -05001208 CFG_SYS_NAND_U_BOOT_START
Scott Wood7d4b7952012-09-21 18:35:27 -05001209 Entry point in loaded image to jump to
Tom Rini95579792012-02-14 07:29:40 +00001210
Pavel Machekc57b9532012-08-30 22:42:11 +02001211 CONFIG_SPL_RAM_DEVICE
1212 Support for running image already present in ram, in SPL binary
1213
Marek Vasutb527b9c2018-05-13 00:22:52 +02001214 CONFIG_SPL_FIT_PRINT
Simon Glass87ebee32013-05-08 08:05:59 +00001215 Printing information about a FIT image adds quite a bit of
1216 code to SPL. So this is normally disabled in SPL. Use this
1217 option to re-enable it. This will affect the output of the
1218 bootm command when booting a FIT image.
1219
wdenka8c7c702003-12-06 19:49:23 +00001220- Interrupt support (PPC):
1221
wdenkd4ca31c2004-01-02 14:00:00 +00001222 There are common interrupt_init() and timer_interrupt()
1223 for all PPC archs. interrupt_init() calls interrupt_init_cpu()
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02001224 for CPU specific initialization. interrupt_init_cpu()
wdenkd4ca31c2004-01-02 14:00:00 +00001225 should set decrementer_count to appropriate value. If
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02001226 CPU resets decrementer automatically after interrupt
wdenkd4ca31c2004-01-02 14:00:00 +00001227 (ppc4xx) it should set decrementer_count to zero.
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02001228 timer_interrupt() calls timer_interrupt_cpu() for CPU
wdenkd4ca31c2004-01-02 14:00:00 +00001229 specific handling. If board has watchdog / status_led
1230 / other_activity_monitor it works automatically from
1231 general timer_interrupt().
wdenka8c7c702003-12-06 19:49:23 +00001232
wdenkc6097192002-11-03 00:24:07 +00001233
Helmut Raiger9660e442011-10-20 04:19:47 +00001234Board initialization settings:
1235------------------------------
1236
1237During Initialization u-boot calls a number of board specific functions
1238to allow the preparation of board specific prerequisites, e.g. pin setup
1239before drivers are initialized. To enable these callbacks the
1240following configuration macros have to be defined. Currently this is
1241architecture specific, so please check arch/your_architecture/lib/board.c
1242typically in board_init_f() and board_init_r().
1243
1244- CONFIG_BOARD_EARLY_INIT_F: Call board_early_init_f()
1245- CONFIG_BOARD_EARLY_INIT_R: Call board_early_init_r()
1246- CONFIG_BOARD_LATE_INIT: Call board_late_init()
wdenkc6097192002-11-03 00:24:07 +00001247
wdenkc6097192002-11-03 00:24:07 +00001248Configuration Settings:
1249-----------------------
1250
Simon Glass4d979bf2019-12-28 10:45:10 -07001251- MEM_SUPPORT_64BIT_DATA: Defined automatically if compiled as 64-bit.
York Sun4d1fd7f2014-02-26 17:03:19 -08001252 Optionally it can be defined to support 64-bit memory commands.
1253
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02001254- CONFIG_SYS_LONGHELP: Defined when you want long help messages included;
wdenkc6097192002-11-03 00:24:07 +00001255 undefine this when you're short of memory.
1256
Tom Rini6e7df1d2023-01-10 11:19:45 -05001257- CFG_SYS_HELP_CMD_WIDTH: Defined when you want to override the default
Peter Tyser2fb26042009-01-27 18:03:12 -06001258 width of the commands listed in the 'help' command output.
1259
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02001260- CONFIG_SYS_PROMPT: This is what U-Boot prints on the console to
wdenkc6097192002-11-03 00:24:07 +00001261 prompt for user input.
1262
Tom Rini65cc0e22022-11-16 13:10:41 -05001263- CFG_SYS_BAUDRATE_TABLE:
wdenkc6097192002-11-03 00:24:07 +00001264 List of legal baudrate settings for this board.
1265
Tom Rini65cc0e22022-11-16 13:10:41 -05001266- CFG_SYS_MEM_RESERVE_SECURE
York Sune61a7532016-06-24 16:46:18 -07001267 Only implemented for ARMv8 for now.
Tom Rini65cc0e22022-11-16 13:10:41 -05001268 If defined, the size of CFG_SYS_MEM_RESERVE_SECURE memory
York Sune8149522015-12-04 11:57:07 -08001269 is substracted from total RAM and won't be reported to OS.
1270 This memory can be used as secure memory. A variable
York Sune61a7532016-06-24 16:46:18 -07001271 gd->arch.secure_ram is used to track the location. In systems
York Sune8149522015-12-04 11:57:07 -08001272 the RAM base is not zero, or RAM is divided into banks,
1273 this variable needs to be recalcuated to get the address.
1274
Tom Riniaa6e94d2022-11-16 13:10:37 -05001275- CFG_SYS_SDRAM_BASE:
wdenkc6097192002-11-03 00:24:07 +00001276 Physical start address of SDRAM. _Must_ be 0 here.
1277
Tom Rini65cc0e22022-11-16 13:10:41 -05001278- CFG_SYS_FLASH_BASE:
wdenkc6097192002-11-03 00:24:07 +00001279 Physical start address of Flash memory.
1280
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02001281- CONFIG_SYS_MALLOC_LEN:
wdenkc6097192002-11-03 00:24:07 +00001282 Size of DRAM reserved for malloc() use.
1283
Simon Glassd59476b2014-07-10 22:23:28 -06001284- CONFIG_SYS_MALLOC_F_LEN
1285 Size of the malloc() pool for use before relocation. If
1286 this is defined, then a very simple malloc() implementation
1287 will become available before relocation. The address is just
1288 below the global data, and the stack is moved down to make
1289 space.
1290
1291 This feature allocates regions with increasing addresses
1292 within the region. calloc() is supported, but realloc()
1293 is not available. free() is supported but does nothing.
Jeremiah Mahlerb445bbb2015-01-04 18:56:50 -08001294 The memory will be freed (or in fact just forgotten) when
Simon Glassd59476b2014-07-10 22:23:28 -06001295 U-Boot relocates itself.
1296
Simon Glass38687ae2014-11-10 17:16:54 -07001297- CONFIG_SYS_MALLOC_SIMPLE
1298 Provides a simple and small malloc() and calloc() for those
1299 boards which do not use the full malloc in SPL (which is
Tom Rini10f6e4d2022-05-27 12:48:32 -04001300 enabled with CONFIG_SYS_SPL_MALLOC).
Simon Glass38687ae2014-11-10 17:16:54 -07001301
Tom Rini65cc0e22022-11-16 13:10:41 -05001302- CFG_SYS_BOOTMAPSZ:
wdenkc6097192002-11-03 00:24:07 +00001303 Maximum size of memory mapped by the startup code of
1304 the Linux kernel; all data that must be processed by
Bartlomiej Sieka7d721e32008-04-14 15:44:16 +02001305 the Linux kernel (bd_info, boot arguments, FDT blob if
1306 used) must be put below this limit, unless "bootm_low"
Robert P. J. Day1bce2ae2013-09-16 07:15:45 -04001307 environment variable is defined and non-zero. In such case
Bartlomiej Sieka7d721e32008-04-14 15:44:16 +02001308 all data for the Linux kernel must be between "bootm_low"
Tom Rini65cc0e22022-11-16 13:10:41 -05001309 and "bootm_low" + CFG_SYS_BOOTMAPSZ. The environment
Grant Likelyc3624e62011-03-28 09:58:43 +00001310 variable "bootm_mapsize" will override the value of
Tom Rini65cc0e22022-11-16 13:10:41 -05001311 CFG_SYS_BOOTMAPSZ. If CFG_SYS_BOOTMAPSZ is undefined,
Grant Likelyc3624e62011-03-28 09:58:43 +00001312 then the value in "bootm_size" will be used instead.
wdenkc6097192002-11-03 00:24:07 +00001313
John Rigbyfca43cc2010-10-13 13:57:35 -06001314- CONFIG_SYS_BOOT_GET_CMDLINE:
1315 Enables allocating and saving kernel cmdline in space between
1316 "bootm_low" and "bootm_low" + BOOTMAPSZ.
1317
1318- CONFIG_SYS_BOOT_GET_KBD:
1319 Enables allocating and saving a kernel copy of the bd_info in
1320 space between "bootm_low" and "bootm_low" + BOOTMAPSZ.
1321
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02001322- CONFIG_SYS_FLASH_PROTECTION
wdenk8564acf2003-07-14 22:13:32 +00001323 If defined, hardware flash sectors protection is used
1324 instead of U-Boot software protection.
1325
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02001326- CONFIG_SYS_FLASH_CFI:
wdenk43d96162003-03-06 00:02:04 +00001327 Define if the flash driver uses extra elements in the
wdenk5653fc32004-02-08 22:55:38 +00001328 common flash structure for storing flash geometry.
1329
Jean-Christophe PLAGNIOL-VILLARD00b18832008-08-13 01:40:42 +02001330- CONFIG_FLASH_CFI_DRIVER
wdenk5653fc32004-02-08 22:55:38 +00001331 This option also enables the building of the cfi_flash driver
1332 in the drivers directory
wdenkc6097192002-11-03 00:24:07 +00001333
Piotr Ziecik91809ed2008-11-17 15:57:58 +01001334- CONFIG_FLASH_CFI_MTD
1335 This option enables the building of the cfi_mtd driver
1336 in the drivers directory. The driver exports CFI flash
1337 to the MTD layer.
1338
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02001339- CONFIG_SYS_FLASH_USE_BUFFER_WRITE
Guennadi Liakhovetski96ef8312008-04-03 13:36:02 +02001340 Use buffered writes to flash.
1341
Joe Hershberger25980902012-12-11 22:16:31 -06001342- CONFIG_ENV_FLAGS_LIST_DEFAULT
Tom Riniacf29d82022-12-04 10:03:40 -05001343- CFG_ENV_FLAGS_LIST_STATIC
Robert P. J. Day1bce2ae2013-09-16 07:15:45 -04001344 Enable validation of the values given to environment variables when
Joe Hershberger25980902012-12-11 22:16:31 -06001345 calling env set. Variables can be restricted to only decimal,
1346 hexadecimal, or boolean. If CONFIG_CMD_NET is also defined,
1347 the variables can also be restricted to IP address or MAC address.
1348
1349 The format of the list is:
1350 type_attribute = [s|d|x|b|i|m]
Jeremiah Mahlerb445bbb2015-01-04 18:56:50 -08001351 access_attribute = [a|r|o|c]
1352 attributes = type_attribute[access_attribute]
Joe Hershberger25980902012-12-11 22:16:31 -06001353 entry = variable_name[:attributes]
1354 list = entry[,list]
1355
1356 The type attributes are:
1357 s - String (default)
1358 d - Decimal
1359 x - Hexadecimal
1360 b - Boolean ([1yYtT|0nNfF])
1361 i - IP address
1362 m - MAC address
1363
Joe Hershberger267541f2012-12-11 22:16:34 -06001364 The access attributes are:
1365 a - Any (default)
1366 r - Read-only
1367 o - Write-once
1368 c - Change-default
1369
Joe Hershberger25980902012-12-11 22:16:31 -06001370 - CONFIG_ENV_FLAGS_LIST_DEFAULT
1371 Define this to a list (string) to define the ".flags"
Jeremiah Mahlerb445bbb2015-01-04 18:56:50 -08001372 environment variable in the default or embedded environment.
Joe Hershberger25980902012-12-11 22:16:31 -06001373
Tom Riniacf29d82022-12-04 10:03:40 -05001374 - CFG_ENV_FLAGS_LIST_STATIC
Joe Hershberger25980902012-12-11 22:16:31 -06001375 Define this to a list (string) to define validation that
1376 should be done if an entry is not found in the ".flags"
1377 environment variable. To override a setting in the static
1378 list, simply add an entry for the same variable name to the
1379 ".flags" variable.
1380
Joe Hershbergerbdf1fe42015-05-20 14:27:20 -05001381 If CONFIG_REGEX is defined, the variable_name above is evaluated as a
1382 regular expression. This allows multiple variables to define the same
1383 flags without explicitly listing them for each variable.
1384
wdenkc6097192002-11-03 00:24:07 +00001385The following definitions that deal with the placement and management
1386of environment data (variable area); in general, we support the
1387following configurations:
1388
wdenkc6097192002-11-03 00:24:07 +00001389BE CAREFUL! The first access to the environment happens quite early
Jeremiah Mahlerb445bbb2015-01-04 18:56:50 -08001390in U-Boot initialization (when we try to get the setting of for the
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02001391console baudrate). You *MUST* have mapped your NVRAM area then, or
wdenkc6097192002-11-03 00:24:07 +00001392U-Boot will hang.
1393
1394Please note that even with NVRAM we still use a copy of the
1395environment in RAM: we could work on NVRAM directly, but we want to
1396keep settings there always unmodified except somebody uses "saveenv"
1397to save the current settings.
1398
Liu Gang0a85a9e2012-03-08 00:33:20 +00001399BE CAREFUL! For some special cases, the local device can not use
1400"saveenv" command. For example, the local device will get the
Liu Gangfc54c7f2012-08-09 05:10:01 +00001401environment stored in a remote NOR flash by SRIO or PCIE link,
1402but it can not erase, write this NOR flash by SRIO or PCIE interface.
Liu Gang0a85a9e2012-03-08 00:33:20 +00001403
Guennadi Liakhovetskib74ab732009-05-18 16:07:22 +02001404- CONFIG_NAND_ENV_DST
1405
1406 Defines address in RAM to which the nand_spl code should copy the
1407 environment. If redundant environment is used, it will be copied to
1408 CONFIG_NAND_ENV_DST + CONFIG_ENV_SIZE.
1409
Bruce Adlere881cb52007-11-02 13:15:42 -07001410Please note that the environment is read-only until the monitor
wdenkc6097192002-11-03 00:24:07 +00001411has been relocated to RAM and a RAM copy of the environment has been
Simon Glass00caae62017-08-03 12:22:12 -06001412created; also, when using EEPROM you will have to use env_get_f()
wdenkc6097192002-11-03 00:24:07 +00001413until then to read environment variables.
1414
wdenk85ec0bc2003-03-31 16:34:49 +00001415The environment is protected by a CRC32 checksum. Before the monitor
1416is relocated into RAM, as a result of a bad CRC you will be working
1417with the compiled-in default environment - *silently*!!! [This is
1418necessary, because the first environment variable we need is the
1419"baudrate" setting for the console - if we have a bad CRC, we don't
1420have any device yet where we could complain.]
wdenkc6097192002-11-03 00:24:07 +00001421
1422Note: once the monitor has been relocated, then it will complain if
1423the default environment is used; a new CRC is computed as soon as you
wdenk85ec0bc2003-03-31 16:34:49 +00001424use the "saveenv" command to store a valid environment.
wdenkc6097192002-11-03 00:24:07 +00001425
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02001426- CONFIG_SYS_FAULT_MII_ADDR:
wdenk42d1f032003-10-15 23:53:47 +00001427 MII address of the PHY to check for the Ethernet link state.
wdenkc6097192002-11-03 00:24:07 +00001428
Simon Glassb2b92f52012-11-30 13:01:18 +00001429- CONFIG_DISPLAY_BOARDINFO
1430 Display information about the board that U-Boot is running on
1431 when U-Boot starts up. The board function checkboard() is called
1432 to do this.
1433
Simon Glasse2e3e2b2012-11-30 13:01:19 +00001434- CONFIG_DISPLAY_BOARDINFO_LATE
1435 Similar to the previous option, but display this information
1436 later, once stdio is running and output goes to the LCD, if
1437 present.
1438
wdenkc6097192002-11-03 00:24:07 +00001439Low Level (hardware related) configuration options:
wdenkdc7c9a12003-03-26 06:55:25 +00001440---------------------------------------------------
wdenkc6097192002-11-03 00:24:07 +00001441
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02001442- CONFIG_SYS_CACHELINE_SIZE:
wdenkc6097192002-11-03 00:24:07 +00001443 Cache Line Size of the CPU.
1444
Timur Tabie46fedf2011-08-04 18:03:41 -05001445- CONFIG_SYS_CCSRBAR_DEFAULT:
1446 Default (power-on reset) physical address of CCSR on Freescale
1447 PowerPC SOCs.
1448
Tom Rini65cc0e22022-11-16 13:10:41 -05001449- CFG_SYS_CCSRBAR:
Timur Tabie46fedf2011-08-04 18:03:41 -05001450 Virtual address of CCSR. On a 32-bit build, this is typically
1451 the same value as CONFIG_SYS_CCSRBAR_DEFAULT.
1452
Tom Rini65cc0e22022-11-16 13:10:41 -05001453- CFG_SYS_CCSRBAR_PHYS:
Timur Tabie46fedf2011-08-04 18:03:41 -05001454 Physical address of CCSR. CCSR can be relocated to a new
1455 physical address, if desired. In this case, this macro should
Wolfgang Denkc0f40852011-10-26 10:21:21 +00001456 be set to that address. Otherwise, it should be set to the
Timur Tabie46fedf2011-08-04 18:03:41 -05001457 same value as CONFIG_SYS_CCSRBAR_DEFAULT. For example, CCSR
1458 is typically relocated on 36-bit builds. It is recommended
1459 that this macro be defined via the _HIGH and _LOW macros:
1460
Tom Rini65cc0e22022-11-16 13:10:41 -05001461 #define CFG_SYS_CCSRBAR_PHYS ((CFG_SYS_CCSRBAR_PHYS_HIGH
1462 * 1ull) << 32 | CFG_SYS_CCSRBAR_PHYS_LOW)
Timur Tabie46fedf2011-08-04 18:03:41 -05001463
Tom Rini65cc0e22022-11-16 13:10:41 -05001464- CFG_SYS_CCSRBAR_PHYS_HIGH:
1465 Bits 33-36 of CFG_SYS_CCSRBAR_PHYS. This value is typically
Wolfgang Denk4cf26092011-10-07 09:58:21 +02001466 either 0 (32-bit build) or 0xF (36-bit build). This macro is
Timur Tabie46fedf2011-08-04 18:03:41 -05001467 used in assembly code, so it must not contain typecasts or
1468 integer size suffixes (e.g. "ULL").
1469
Tom Rini65cc0e22022-11-16 13:10:41 -05001470- CFG_SYS_CCSRBAR_PHYS_LOW:
1471 Lower 32-bits of CFG_SYS_CCSRBAR_PHYS. This macro is
Timur Tabie46fedf2011-08-04 18:03:41 -05001472 used in assembly code, so it must not contain typecasts or
1473 integer size suffixes (e.g. "ULL").
1474
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02001475- CONFIG_SYS_IMMR: Physical address of the Internal Memory.
wdenkefe2a4d2004-12-16 21:44:03 +00001476 DO NOT CHANGE unless you know exactly what you're
Christophe Leroy907208c2017-07-06 10:23:22 +02001477 doing! (11-4) [MPC8xx systems only]
wdenkc6097192002-11-03 00:24:07 +00001478
Tom Rini65cc0e22022-11-16 13:10:41 -05001479- CFG_SYS_INIT_RAM_ADDR:
wdenkc6097192002-11-03 00:24:07 +00001480
wdenk7152b1d2003-09-05 23:19:14 +00001481 Start address of memory area that can be used for
wdenkc6097192002-11-03 00:24:07 +00001482 initial data and stack; please note that this must be
1483 writable memory that is working WITHOUT special
1484 initialization, i. e. you CANNOT use normal RAM which
1485 will become available only after programming the
1486 memory controller and running certain initialization
1487 sequences.
1488
1489 U-Boot uses the following memory types:
Christophe Leroy907208c2017-07-06 10:23:22 +02001490 - MPC8xx: IMMR (internal memory of the CPU)
wdenkc6097192002-11-03 00:24:07 +00001491
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02001492- CONFIG_SYS_SCCR: System Clock and reset Control Register (15-27)
wdenkc6097192002-11-03 00:24:07 +00001493
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02001494- CONFIG_SYS_OR_TIMING_SDRAM:
wdenkc6097192002-11-03 00:24:07 +00001495 SDRAM timing
1496
Kumar Galaa09b9b62010-12-30 12:09:53 -06001497- CONFIG_SYS_SRIOn_MEM_VIRT:
1498 Virtual Address of SRIO port 'n' memory region
1499
Simon Glass62f9b652019-11-14 12:57:09 -07001500- CONFIG_SYS_SRIOn_MEM_PHYxS:
Kumar Galaa09b9b62010-12-30 12:09:53 -06001501 Physical Address of SRIO port 'n' memory region
1502
1503- CONFIG_SYS_SRIOn_MEM_SIZE:
1504 Size of SRIO port 'n' memory region
1505
Fabio Estevam66bd1842013-04-11 09:35:34 +00001506- CONFIG_SYS_NAND_BUSWIDTH_16BIT
1507 Defined to tell the NAND controller that the NAND chip is using
1508 a 16 bit bus.
1509 Not all NAND drivers use this symbol.
Fabio Estevama430e912013-04-11 09:35:35 +00001510 Example of drivers that use it:
Miquel Raynala430fa02018-08-16 17:30:07 +02001511 - drivers/mtd/nand/raw/ndfc.c
1512 - drivers/mtd/nand/raw/mxc_nand.c
Alex Watermaneced4622011-05-19 15:08:36 -04001513
1514- CONFIG_SYS_NDFC_EBC0_CFG
1515 Sets the EBC0_CFG register for the NDFC. If not defined
1516 a default value will be used.
1517
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02001518- CONFIG_SYS_SPD_BUS_NUM
Wolfgang Denk218ca722008-03-26 10:40:12 +01001519 If SPD EEPROM is on an I2C bus other than the first
1520 one, specify here. Note that the value must resolve
1521 to something your driver can deal with.
Ben Warrenbb99ad62006-09-07 16:50:54 -04001522
York Sun6f5e1dc2011-09-16 13:21:35 -07001523- CONFIG_FSL_DDR_INTERACTIVE
1524 Enable interactive DDR debugging. See doc/README.fsl-ddr.
1525
York Sune32d59a2015-01-06 13:18:55 -08001526- CONFIG_FSL_DDR_SYNC_REFRESH
1527 Enable sync of refresh for multiple controllers.
1528
York Sun4516ff82015-03-19 09:30:28 -07001529- CONFIG_FSL_DDR_BIST
1530 Enable built-in memory test for Freescale DDR controllers.
1531
wdenkc26e4542004-04-18 10:13:26 +00001532- CONFIG_RMII
1533 Enable RMII mode for all FECs.
1534 Note that this is a global option, we can't
1535 have one FEC in standard MII mode and another in RMII mode.
1536
wdenk5cf91d62004-04-23 20:32:05 +00001537- CONFIG_CRC32_VERIFY
1538 Add a verify option to the crc32 command.
1539 The syntax is:
1540
1541 => crc32 -v <address> <count> <crc32>
1542
1543 Where address/count indicate a memory area
1544 and crc32 is the correct crc32 which the
1545 area should have.
1546
wdenk56523f12004-07-11 17:40:54 +00001547- CONFIG_LOOPW
1548 Add the "loopw" memory command. This only takes effect if
Simon Glass493f4202017-08-04 16:34:27 -06001549 the memory commands are activated globally (CONFIG_CMD_MEMORY).
wdenk56523f12004-07-11 17:40:54 +00001550
Joel Johnson72732312020-01-29 09:17:18 -07001551- CONFIG_CMD_MX_CYCLIC
stroese7b466642004-12-16 18:46:55 +00001552 Add the "mdc" and "mwc" memory commands. These are cyclic
1553 "md/mw" commands.
1554 Examples:
1555
wdenkefe2a4d2004-12-16 21:44:03 +00001556 => mdc.b 10 4 500
stroese7b466642004-12-16 18:46:55 +00001557 This command will print 4 bytes (10,11,12,13) each 500 ms.
1558
wdenkefe2a4d2004-12-16 21:44:03 +00001559 => mwc.l 100 12345678 10
stroese7b466642004-12-16 18:46:55 +00001560 This command will write 12345678 to address 100 all 10 ms.
1561
wdenkefe2a4d2004-12-16 21:44:03 +00001562 This only takes effect if the memory commands are activated
Simon Glass493f4202017-08-04 16:34:27 -06001563 globally (CONFIG_CMD_MEMORY).
stroese7b466642004-12-16 18:46:55 +00001564
Aneesh V401bb302011-07-13 05:11:07 +00001565- CONFIG_SPL_BUILD
Thomas Hebb32f2ca22019-11-13 18:18:03 -08001566 Set when the currently-running compilation is for an artifact
1567 that will end up in the SPL (as opposed to the TPL or U-Boot
1568 proper). Code that needs stage-specific behavior should check
1569 this.
wdenk400558b2005-04-02 23:52:25 +00001570
Ying Zhang3aa29de2013-08-16 15:16:15 +08001571- CONFIG_TPL_BUILD
Thomas Hebb32f2ca22019-11-13 18:18:03 -08001572 Set when the currently-running compilation is for an artifact
1573 that will end up in the TPL (as opposed to the SPL or U-Boot
1574 proper). Code that needs stage-specific behavior should check
1575 this.
Ying Zhang3aa29de2013-08-16 15:16:15 +08001576
Simon Glass4213fc22013-02-24 17:33:14 +00001577- CONFIG_ARCH_MAP_SYSMEM
1578 Generally U-Boot (and in particular the md command) uses
1579 effective address. It is therefore not necessary to regard
1580 U-Boot address as virtual addresses that need to be translated
1581 to physical addresses. However, sandbox requires this, since
1582 it maintains its own little RAM buffer which contains all
1583 addressable memory. This option causes some memory accesses
1584 to be mapped through map_sysmem() / unmap_sysmem().
1585
Simon Glass588a13f2013-02-14 04:18:54 +00001586- CONFIG_X86_RESET_VECTOR
1587 If defined, the x86 reset vector code is included. This is not
1588 needed when U-Boot is running from Coreboot.
Gabe Blackb16f5212012-11-27 21:08:06 +00001589
Timur Tabif2717b42011-11-22 09:21:25 -06001590Freescale QE/FMAN Firmware Support:
1591-----------------------------------
1592
1593The Freescale QUICCEngine (QE) and Frame Manager (FMAN) both support the
1594loading of "firmware", which is encoded in the QE firmware binary format.
1595This firmware often needs to be loaded during U-Boot booting, so macros
1596are used to identify the storage device (NOR flash, SPI, etc) and the address
1597within that device.
1598
Zhao Qiangdcf1d772014-03-21 16:21:44 +08001599- CONFIG_SYS_FMAN_FW_ADDR
1600 The address in the storage device where the FMAN microcode is located. The
Tom Rinicc1e98b2019-05-12 07:59:12 -04001601 meaning of this address depends on which CONFIG_SYS_QE_FMAN_FW_IN_xxx macro
Zhao Qiangdcf1d772014-03-21 16:21:44 +08001602 is also specified.
1603
1604- CONFIG_SYS_QE_FW_ADDR
1605 The address in the storage device where the QE microcode is located. The
Tom Rinicc1e98b2019-05-12 07:59:12 -04001606 meaning of this address depends on which CONFIG_SYS_QE_FMAN_FW_IN_xxx macro
Timur Tabif2717b42011-11-22 09:21:25 -06001607 is also specified.
1608
1609- CONFIG_SYS_QE_FMAN_FW_LENGTH
1610 The maximum possible size of the firmware. The firmware binary format
1611 has a field that specifies the actual size of the firmware, but it
1612 might not be possible to read any part of the firmware unless some
1613 local storage is allocated to hold the entire firmware first.
1614
1615- CONFIG_SYS_QE_FMAN_FW_IN_NOR
1616 Specifies that QE/FMAN firmware is located in NOR flash, mapped as
1617 normal addressable memory via the LBC. CONFIG_SYS_FMAN_FW_ADDR is the
1618 virtual address in NOR flash.
1619
1620- CONFIG_SYS_QE_FMAN_FW_IN_NAND
1621 Specifies that QE/FMAN firmware is located in NAND flash.
1622 CONFIG_SYS_FMAN_FW_ADDR is the offset within NAND flash.
1623
1624- CONFIG_SYS_QE_FMAN_FW_IN_MMC
1625 Specifies that QE/FMAN firmware is located on the primary SD/MMC
1626 device. CONFIG_SYS_FMAN_FW_ADDR is the byte offset on that device.
1627
Liu Gang292dc6c2012-03-08 00:33:18 +00001628- CONFIG_SYS_QE_FMAN_FW_IN_REMOTE
1629 Specifies that QE/FMAN firmware is located in the remote (master)
1630 memory space. CONFIG_SYS_FMAN_FW_ADDR is a virtual address which
Liu Gangfc54c7f2012-08-09 05:10:01 +00001631 can be mapped from slave TLB->slave LAW->slave SRIO or PCIE outbound
1632 window->master inbound window->master LAW->the ucode address in
1633 master's memory space.
Timur Tabif2717b42011-11-22 09:21:25 -06001634
J. German Riverab940ca62014-06-23 15:15:55 -07001635Freescale Layerscape Management Complex Firmware Support:
1636---------------------------------------------------------
1637The Freescale Layerscape Management Complex (MC) supports the loading of
1638"firmware".
1639This firmware often needs to be loaded during U-Boot booting, so macros
1640are used to identify the storage device (NOR flash, SPI, etc) and the address
1641within that device.
1642
1643- CONFIG_FSL_MC_ENET
1644 Enable the MC driver for Layerscape SoCs.
1645
Prabhakar Kushwaha5c055082015-06-02 10:55:52 +05301646Freescale Layerscape Debug Server Support:
1647-------------------------------------------
1648The Freescale Layerscape Debug Server Support supports the loading of
1649"Debug Server firmware" and triggering SP boot-rom.
1650This firmware often needs to be loaded during U-Boot booting.
1651
York Sunc0492142015-12-07 11:08:58 -08001652- CONFIG_SYS_MC_RSV_MEM_ALIGN
1653 Define alignment of reserved memory MC requires
Prabhakar Kushwaha5c055082015-06-02 10:55:52 +05301654
Paul Kocialkowskif3f431a2015-07-26 18:48:15 +02001655
wdenkc6097192002-11-03 00:24:07 +00001656Building the Software:
1657======================
1658
Wolfgang Denk218ca722008-03-26 10:40:12 +01001659Building U-Boot has been tested in several native build environments
1660and in many different cross environments. Of course we cannot support
1661all possibly existing versions of cross development tools in all
1662(potentially obsolete) versions. In case of tool chain problems we
Naoki Hayama047f6ec2020-10-08 13:17:16 +09001663recommend to use the ELDK (see https://www.denx.de/wiki/DULG/ELDK)
Wolfgang Denk218ca722008-03-26 10:40:12 +01001664which is extensively used to build and test U-Boot.
wdenkc6097192002-11-03 00:24:07 +00001665
Wolfgang Denk218ca722008-03-26 10:40:12 +01001666If you are not using a native environment, it is assumed that you
1667have GNU cross compiling tools available in your path. In this case,
1668you must set the environment variable CROSS_COMPILE in your shell.
1669Note that no changes to the Makefile or any other source files are
1670necessary. For example using the ELDK on a 4xx CPU, please enter:
wdenkc6097192002-11-03 00:24:07 +00001671
Wolfgang Denk218ca722008-03-26 10:40:12 +01001672 $ CROSS_COMPILE=ppc_4xx-
1673 $ export CROSS_COMPILE
wdenkc6097192002-11-03 00:24:07 +00001674
Wolfgang Denk218ca722008-03-26 10:40:12 +01001675U-Boot is intended to be simple to build. After installing the
1676sources you must configure U-Boot for one specific board type. This
wdenkc6097192002-11-03 00:24:07 +00001677is done by typing:
1678
Holger Freytherab584d62014-08-04 09:26:05 +02001679 make NAME_defconfig
wdenkc6097192002-11-03 00:24:07 +00001680
Holger Freytherab584d62014-08-04 09:26:05 +02001681where "NAME_defconfig" is the name of one of the existing configu-
Heinrich Schuchardtecb3a0a2020-02-24 18:36:30 +01001682rations; see configs/*_defconfig for supported names.
wdenk54387ac2003-10-08 22:45:44 +00001683
Heinrich Schuchardtecb3a0a2020-02-24 18:36:30 +01001684Note: for some boards special configuration names may exist; check if
wdenk2729af92004-05-03 20:45:30 +00001685 additional information is available from the board vendor; for
1686 instance, the TQM823L systems are available without (standard)
1687 or with LCD support. You can select such additional "features"
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02001688 when choosing the configuration, i. e.
wdenkc6097192002-11-03 00:24:07 +00001689
Holger Freytherab584d62014-08-04 09:26:05 +02001690 make TQM823L_defconfig
wdenk2729af92004-05-03 20:45:30 +00001691 - will configure for a plain TQM823L, i. e. no LCD support
wdenkc6097192002-11-03 00:24:07 +00001692
Holger Freytherab584d62014-08-04 09:26:05 +02001693 make TQM823L_LCD_defconfig
wdenk2729af92004-05-03 20:45:30 +00001694 - will configure for a TQM823L with U-Boot console on LCD
wdenkc6097192002-11-03 00:24:07 +00001695
wdenk2729af92004-05-03 20:45:30 +00001696 etc.
wdenkc6097192002-11-03 00:24:07 +00001697
wdenkc6097192002-11-03 00:24:07 +00001698
wdenk2729af92004-05-03 20:45:30 +00001699Finally, type "make all", and you should get some working U-Boot
1700images ready for download to / installation on your system:
wdenkc6097192002-11-03 00:24:07 +00001701
wdenk2729af92004-05-03 20:45:30 +00001702- "u-boot.bin" is a raw binary image
1703- "u-boot" is an image in ELF binary format
1704- "u-boot.srec" is in Motorola S-Record format
wdenkc6097192002-11-03 00:24:07 +00001705
Marian Balakowiczbaf31242006-09-07 17:25:40 +02001706By default the build is performed locally and the objects are saved
1707in the source directory. One of the two methods can be used to change
1708this behavior and build U-Boot to some external directory:
1709
17101. Add O= to the make command line invocations:
1711
1712 make O=/tmp/build distclean
Holger Freytherab584d62014-08-04 09:26:05 +02001713 make O=/tmp/build NAME_defconfig
Marian Balakowiczbaf31242006-09-07 17:25:40 +02001714 make O=/tmp/build all
1715
Timo Ketolaadbba992014-11-06 14:39:05 +020017162. Set environment variable KBUILD_OUTPUT to point to the desired location:
Marian Balakowiczbaf31242006-09-07 17:25:40 +02001717
Timo Ketolaadbba992014-11-06 14:39:05 +02001718 export KBUILD_OUTPUT=/tmp/build
Marian Balakowiczbaf31242006-09-07 17:25:40 +02001719 make distclean
Holger Freytherab584d62014-08-04 09:26:05 +02001720 make NAME_defconfig
Marian Balakowiczbaf31242006-09-07 17:25:40 +02001721 make all
1722
Timo Ketolaadbba992014-11-06 14:39:05 +02001723Note that the command line "O=" setting overrides the KBUILD_OUTPUT environment
Marian Balakowiczbaf31242006-09-07 17:25:40 +02001724variable.
1725
Daniel Schwierzeck215bb1c2018-01-26 16:31:04 +01001726User specific CPPFLAGS, AFLAGS and CFLAGS can be passed to the compiler by
1727setting the according environment variables KCPPFLAGS, KAFLAGS and KCFLAGS.
1728For example to treat all compiler warnings as errors:
1729
1730 make KCFLAGS=-Werror
wdenkc6097192002-11-03 00:24:07 +00001731
wdenk2729af92004-05-03 20:45:30 +00001732Please be aware that the Makefiles assume you are using GNU make, so
1733for instance on NetBSD you might need to use "gmake" instead of
1734native "make".
wdenkc6097192002-11-03 00:24:07 +00001735
wdenkc6097192002-11-03 00:24:07 +00001736
wdenk2729af92004-05-03 20:45:30 +00001737If the system board that you have is not listed, then you will need
1738to port U-Boot to your hardware platform. To do this, follow these
1739steps:
wdenkc6097192002-11-03 00:24:07 +00001740
Phil Sutter3c1496c2015-12-25 14:41:18 +010017411. Create a new directory to hold your board specific code. Add any
wdenk2729af92004-05-03 20:45:30 +00001742 files you need. In your board directory, you will need at least
Phil Sutter3c1496c2015-12-25 14:41:18 +01001743 the "Makefile" and a "<board>.c".
17442. Create a new configuration file "include/configs/<board>.h" for
1745 your board.
wdenk2729af92004-05-03 20:45:30 +000017463. If you're porting U-Boot to a new CPU, then also create a new
1747 directory to hold your CPU specific code. Add any files you need.
Holger Freytherab584d62014-08-04 09:26:05 +020017484. Run "make <board>_defconfig" with your new name.
wdenk2729af92004-05-03 20:45:30 +000017495. Type "make", and you should get a working "u-boot.srec" file
1750 to be installed on your target system.
17516. Debug and solve any problems that might arise.
1752 [Of course, this last step is much harder than it sounds.]
wdenkc6097192002-11-03 00:24:07 +00001753
wdenkc6097192002-11-03 00:24:07 +00001754
wdenk2729af92004-05-03 20:45:30 +00001755Testing of U-Boot Modifications, Ports to New Hardware, etc.:
1756==============================================================
wdenkc6097192002-11-03 00:24:07 +00001757
Wolfgang Denk218ca722008-03-26 10:40:12 +01001758If you have modified U-Boot sources (for instance added a new board
1759or support for new devices, a new CPU, etc.) you are expected to
wdenk2729af92004-05-03 20:45:30 +00001760provide feedback to the other developers. The feedback normally takes
Thomas Hebb32f2ca22019-11-13 18:18:03 -08001761the form of a "patch", i.e. a context diff against a certain (latest
Wolfgang Denk218ca722008-03-26 10:40:12 +01001762official or latest in the git repository) version of U-Boot sources.
wdenkc6097192002-11-03 00:24:07 +00001763
Wolfgang Denk218ca722008-03-26 10:40:12 +01001764But before you submit such a patch, please verify that your modifi-
1765cation did not break existing code. At least make sure that *ALL* of
wdenk2729af92004-05-03 20:45:30 +00001766the supported boards compile WITHOUT ANY compiler warnings. To do so,
Simon Glass6de80f22016-07-27 20:33:08 -06001767just run the buildman script (tools/buildman/buildman), which will
1768configure and build U-Boot for ALL supported system. Be warned, this
1769will take a while. Please see the buildman README, or run 'buildman -H'
1770for documentation.
Marian Balakowiczbaf31242006-09-07 17:25:40 +02001771
1772
wdenk2729af92004-05-03 20:45:30 +00001773See also "U-Boot Porting Guide" below.
wdenkc6097192002-11-03 00:24:07 +00001774
wdenkc6097192002-11-03 00:24:07 +00001775
wdenk2729af92004-05-03 20:45:30 +00001776Monitor Commands - Overview:
1777============================
wdenkc6097192002-11-03 00:24:07 +00001778
wdenk2729af92004-05-03 20:45:30 +00001779go - start application at address 'addr'
1780run - run commands in an environment variable
1781bootm - boot application image from memory
1782bootp - boot image via network using BootP/TFTP protocol
Marek Vasut44f074c2012-03-14 21:52:45 +00001783bootz - boot zImage from memory
wdenk2729af92004-05-03 20:45:30 +00001784tftpboot- boot image via network using TFTP protocol
1785 and env variables "ipaddr" and "serverip"
1786 (and eventually "gatewayip")
Simon Glass1fb7cd42011-10-24 18:00:07 +00001787tftpput - upload a file via network using TFTP protocol
wdenk2729af92004-05-03 20:45:30 +00001788rarpboot- boot image via network using RARP/TFTP protocol
1789diskboot- boot from IDE devicebootd - boot default, i.e., run 'bootcmd'
1790loads - load S-Record file over serial line
1791loadb - load binary file over serial line (kermit mode)
Rui Miguel Silvabfef72e2022-05-11 10:55:40 +01001792loadm - load binary blob from source address to destination address
wdenk2729af92004-05-03 20:45:30 +00001793md - memory display
1794mm - memory modify (auto-incrementing)
1795nm - memory modify (constant address)
1796mw - memory write (fill)
Simon Glassbdded202020-06-02 19:26:49 -06001797ms - memory search
wdenk2729af92004-05-03 20:45:30 +00001798cp - memory copy
1799cmp - memory compare
1800crc32 - checksum calculation
Peter Tyser0f89c542009-04-18 22:34:03 -05001801i2c - I2C sub-system
wdenk2729af92004-05-03 20:45:30 +00001802sspi - SPI utility commands
1803base - print or set address offset
1804printenv- print environment variables
Pragnesh Patel9e9a5302020-12-22 11:30:05 +05301805pwm - control pwm channels
Linus Walleij41a29f22023-02-01 00:16:13 +01001806seama - load SEAMA NAND image
wdenk2729af92004-05-03 20:45:30 +00001807setenv - set environment variables
1808saveenv - save environment variables to persistent storage
1809protect - enable or disable FLASH write protection
1810erase - erase FLASH memory
1811flinfo - print FLASH memory information
Karl O. Pinc10635af2012-08-03 05:57:21 +00001812nand - NAND memory operations (see doc/README.nand)
wdenk2729af92004-05-03 20:45:30 +00001813bdinfo - print Board Info structure
1814iminfo - print header information for application image
1815coninfo - print console devices and informations
1816ide - IDE sub-system
1817loop - infinite loop on address range
wdenk56523f12004-07-11 17:40:54 +00001818loopw - infinite write loop on address range
wdenk2729af92004-05-03 20:45:30 +00001819mtest - simple RAM test
1820icache - enable or disable instruction cache
1821dcache - enable or disable data cache
1822reset - Perform RESET of the CPU
1823echo - echo args to console
1824version - print monitor version
1825help - print online help
1826? - alias for 'help'
wdenkc6097192002-11-03 00:24:07 +00001827
wdenkc6097192002-11-03 00:24:07 +00001828
wdenk2729af92004-05-03 20:45:30 +00001829Monitor Commands - Detailed Description:
1830========================================
wdenkc6097192002-11-03 00:24:07 +00001831
wdenk2729af92004-05-03 20:45:30 +00001832TODO.
wdenkc6097192002-11-03 00:24:07 +00001833
wdenk2729af92004-05-03 20:45:30 +00001834For now: just type "help <command>".
wdenkc6097192002-11-03 00:24:07 +00001835
1836
wdenk2729af92004-05-03 20:45:30 +00001837Note for Redundant Ethernet Interfaces:
1838=======================================
wdenkf07771c2003-05-28 08:06:31 +00001839
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02001840Some boards come with redundant Ethernet interfaces; U-Boot supports
wdenk2729af92004-05-03 20:45:30 +00001841such configurations and is capable of automatic selection of a
1842"working" interface when needed. MAC assignment works as follows:
wdenkf07771c2003-05-28 08:06:31 +00001843
wdenk2729af92004-05-03 20:45:30 +00001844Network interfaces are numbered eth0, eth1, eth2, ... Corresponding
1845MAC addresses can be stored in the environment as "ethaddr" (=>eth0),
1846"eth1addr" (=>eth1), "eth2addr", ...
wdenkf07771c2003-05-28 08:06:31 +00001847
wdenk2729af92004-05-03 20:45:30 +00001848If the network interface stores some valid MAC address (for instance
1849in SROM), this is used as default address if there is NO correspon-
1850ding setting in the environment; if the corresponding environment
1851variable is set, this overrides the settings in the card; that means:
wdenkf07771c2003-05-28 08:06:31 +00001852
wdenk2729af92004-05-03 20:45:30 +00001853o If the SROM has a valid MAC address, and there is no address in the
1854 environment, the SROM's address is used.
wdenkc6097192002-11-03 00:24:07 +00001855
wdenk2729af92004-05-03 20:45:30 +00001856o If there is no valid address in the SROM, and a definition in the
1857 environment exists, then the value from the environment variable is
1858 used.
wdenkc6097192002-11-03 00:24:07 +00001859
wdenk2729af92004-05-03 20:45:30 +00001860o If both the SROM and the environment contain a MAC address, and
1861 both addresses are the same, this MAC address is used.
wdenkc6097192002-11-03 00:24:07 +00001862
wdenk2729af92004-05-03 20:45:30 +00001863o If both the SROM and the environment contain a MAC address, and the
1864 addresses differ, the value from the environment is used and a
1865 warning is printed.
wdenkc6097192002-11-03 00:24:07 +00001866
wdenk2729af92004-05-03 20:45:30 +00001867o If neither SROM nor the environment contain a MAC address, an error
Joe Hershbergerbef10142015-05-04 14:55:13 -05001868 is raised. If CONFIG_NET_RANDOM_ETHADDR is defined, then in this case
1869 a random, locally-assigned MAC is used.
wdenkc6097192002-11-03 00:24:07 +00001870
Ben Warrenecee9322010-04-26 11:11:46 -07001871If Ethernet drivers implement the 'write_hwaddr' function, valid MAC addresses
Wolfgang Denkc0f40852011-10-26 10:21:21 +00001872will be programmed into hardware as part of the initialization process. This
Ben Warrenecee9322010-04-26 11:11:46 -07001873may be skipped by setting the appropriate 'ethmacskip' environment variable.
1874The naming convention is as follows:
1875"ethmacskip" (=>eth0), "eth1macskip" (=>eth1) etc.
wdenkc6097192002-11-03 00:24:07 +00001876
wdenk2729af92004-05-03 20:45:30 +00001877Image Formats:
1878==============
wdenkc6097192002-11-03 00:24:07 +00001879
Marian Balakowicz3310c542008-03-12 12:13:13 +01001880U-Boot is capable of booting (and performing other auxiliary operations on)
1881images in two formats:
1882
1883New uImage format (FIT)
1884-----------------------
1885
1886Flexible and powerful format based on Flattened Image Tree -- FIT (similar
1887to Flattened Device Tree). It allows the use of images with multiple
1888components (several kernels, ramdisks, etc.), with contents protected by
1889SHA1, MD5 or CRC32. More details are found in the doc/uImage.FIT directory.
1890
1891
1892Old uImage format
1893-----------------
1894
1895Old image format is based on binary files which can be basically anything,
1896preceded by a special header; see the definitions in include/image.h for
1897details; basically, the header defines the following image properties:
wdenkc6097192002-11-03 00:24:07 +00001898
wdenk2729af92004-05-03 20:45:30 +00001899* Target Operating System (Provisions for OpenBSD, NetBSD, FreeBSD,
1900 4.4BSD, Linux, SVR4, Esix, Solaris, Irix, SCO, Dell, NCR, VxWorks,
Peter Tyserf5ed9e32008-09-08 14:56:49 -05001901 LynxOS, pSOS, QNX, RTEMS, INTEGRITY;
Thomas Huth0797e732021-11-13 18:13:50 +01001902 Currently supported: Linux, NetBSD, VxWorks, QNX, RTEMS, INTEGRITY).
Andy Shevchenkodaab59a2017-07-05 16:25:22 +03001903* Target CPU Architecture (Provisions for Alpha, ARM, Intel x86,
Tom Rini11232132022-04-06 09:21:25 -04001904 IA64, MIPS, Nios II, PowerPC, IBM S390, SuperH, Sparc, Sparc 64 Bit;
1905 Currently supported: ARM, Intel x86, MIPS, Nios II, PowerPC).
wdenk2729af92004-05-03 20:45:30 +00001906* Compression Type (uncompressed, gzip, bzip2)
1907* Load Address
1908* Entry Point
1909* Image Name
1910* Image Timestamp
wdenkc6097192002-11-03 00:24:07 +00001911
wdenk2729af92004-05-03 20:45:30 +00001912The header is marked by a special Magic Number, and both the header
1913and the data portions of the image are secured against corruption by
1914CRC32 checksums.
wdenkc6097192002-11-03 00:24:07 +00001915
wdenkc6097192002-11-03 00:24:07 +00001916
wdenk2729af92004-05-03 20:45:30 +00001917Linux Support:
1918==============
wdenkc6097192002-11-03 00:24:07 +00001919
wdenk2729af92004-05-03 20:45:30 +00001920Although U-Boot should support any OS or standalone application
1921easily, the main focus has always been on Linux during the design of
1922U-Boot.
wdenkc6097192002-11-03 00:24:07 +00001923
wdenk2729af92004-05-03 20:45:30 +00001924U-Boot includes many features that so far have been part of some
1925special "boot loader" code within the Linux kernel. Also, any
1926"initrd" images to be used are no longer part of one big Linux image;
1927instead, kernel and "initrd" are separate images. This implementation
1928serves several purposes:
wdenkc6097192002-11-03 00:24:07 +00001929
wdenk2729af92004-05-03 20:45:30 +00001930- the same features can be used for other OS or standalone
1931 applications (for instance: using compressed images to reduce the
1932 Flash memory footprint)
wdenkc6097192002-11-03 00:24:07 +00001933
wdenk2729af92004-05-03 20:45:30 +00001934- it becomes much easier to port new Linux kernel versions because
1935 lots of low-level, hardware dependent stuff are done by U-Boot
wdenkc6097192002-11-03 00:24:07 +00001936
wdenk2729af92004-05-03 20:45:30 +00001937- the same Linux kernel image can now be used with different "initrd"
1938 images; of course this also means that different kernel images can
1939 be run with the same "initrd". This makes testing easier (you don't
1940 have to build a new "zImage.initrd" Linux image when you just
1941 change a file in your "initrd"). Also, a field-upgrade of the
1942 software is easier now.
wdenkc6097192002-11-03 00:24:07 +00001943
wdenkc6097192002-11-03 00:24:07 +00001944
wdenk2729af92004-05-03 20:45:30 +00001945Linux HOWTO:
1946============
wdenkc6097192002-11-03 00:24:07 +00001947
wdenk2729af92004-05-03 20:45:30 +00001948Porting Linux to U-Boot based systems:
1949---------------------------------------
wdenkc6097192002-11-03 00:24:07 +00001950
wdenk2729af92004-05-03 20:45:30 +00001951U-Boot cannot save you from doing all the necessary modifications to
1952configure the Linux device drivers for use with your target hardware
1953(no, we don't intend to provide a full virtual machine interface to
1954Linux :-).
wdenkc6097192002-11-03 00:24:07 +00001955
Stefan Roesea47a12b2010-04-15 16:07:28 +02001956But now you can ignore ALL boot loader code (in arch/powerpc/mbxboot).
wdenkc6097192002-11-03 00:24:07 +00001957
wdenk2729af92004-05-03 20:45:30 +00001958Just make sure your machine specific header file (for instance
1959include/asm-ppc/tqm8xx.h) includes the same definition of the Board
Markus Heidelberg1dc30692008-09-07 20:18:27 +02001960Information structure as we define in include/asm-<arch>/u-boot.h,
1961and make sure that your definition of IMAP_ADDR uses the same value
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02001962as your U-Boot configuration in CONFIG_SYS_IMMR.
wdenkc6097192002-11-03 00:24:07 +00001963
Simon Glass2eb31b12014-06-11 23:29:46 -06001964Note that U-Boot now has a driver model, a unified model for drivers.
1965If you are adding a new driver, plumb it into driver model. If there
1966is no uclass available, you are encouraged to create one. See
1967doc/driver-model.
1968
wdenkc6097192002-11-03 00:24:07 +00001969
wdenk2729af92004-05-03 20:45:30 +00001970Configuring the Linux kernel:
1971-----------------------------
wdenkc6097192002-11-03 00:24:07 +00001972
wdenk2729af92004-05-03 20:45:30 +00001973No specific requirements for U-Boot. Make sure you have some root
1974device (initial ramdisk, NFS) for your target system.
wdenkc6097192002-11-03 00:24:07 +00001975
wdenkc6097192002-11-03 00:24:07 +00001976
wdenk2729af92004-05-03 20:45:30 +00001977Building a Linux Image:
1978-----------------------
wdenkc6097192002-11-03 00:24:07 +00001979
wdenk2729af92004-05-03 20:45:30 +00001980With U-Boot, "normal" build targets like "zImage" or "bzImage" are
1981not used. If you use recent kernel source, a new build target
1982"uImage" will exist which automatically builds an image usable by
1983U-Boot. Most older kernels also have support for a "pImage" target,
1984which was introduced for our predecessor project PPCBoot and uses a
1985100% compatible format.
wdenkc6097192002-11-03 00:24:07 +00001986
wdenk2729af92004-05-03 20:45:30 +00001987Example:
wdenkc6097192002-11-03 00:24:07 +00001988
Holger Freytherab584d62014-08-04 09:26:05 +02001989 make TQM850L_defconfig
wdenk2729af92004-05-03 20:45:30 +00001990 make oldconfig
1991 make dep
1992 make uImage
wdenkc6097192002-11-03 00:24:07 +00001993
wdenk2729af92004-05-03 20:45:30 +00001994The "uImage" build target uses a special tool (in 'tools/mkimage') to
1995encapsulate a compressed Linux kernel image with header information,
1996CRC32 checksum etc. for use with U-Boot. This is what we are doing:
wdenkc6097192002-11-03 00:24:07 +00001997
wdenk2729af92004-05-03 20:45:30 +00001998* build a standard "vmlinux" kernel image (in ELF binary format):
wdenkc6097192002-11-03 00:24:07 +00001999
wdenk2729af92004-05-03 20:45:30 +00002000* convert the kernel into a raw binary image:
wdenkc6097192002-11-03 00:24:07 +00002001
wdenk2729af92004-05-03 20:45:30 +00002002 ${CROSS_COMPILE}-objcopy -O binary \
2003 -R .note -R .comment \
2004 -S vmlinux linux.bin
wdenkc6097192002-11-03 00:24:07 +00002005
wdenk2729af92004-05-03 20:45:30 +00002006* compress the binary image:
wdenkc6097192002-11-03 00:24:07 +00002007
wdenk2729af92004-05-03 20:45:30 +00002008 gzip -9 linux.bin
wdenkc6097192002-11-03 00:24:07 +00002009
wdenk2729af92004-05-03 20:45:30 +00002010* package compressed binary image for U-Boot:
wdenk24ee89b2002-11-03 17:56:27 +00002011
wdenk2729af92004-05-03 20:45:30 +00002012 mkimage -A ppc -O linux -T kernel -C gzip \
2013 -a 0 -e 0 -n "Linux Kernel Image" \
2014 -d linux.bin.gz uImage
wdenk24ee89b2002-11-03 17:56:27 +00002015
wdenk24ee89b2002-11-03 17:56:27 +00002016
wdenk2729af92004-05-03 20:45:30 +00002017The "mkimage" tool can also be used to create ramdisk images for use
2018with U-Boot, either separated from the Linux kernel image, or
2019combined into one file. "mkimage" encapsulates the images with a 64
2020byte header containing information about target architecture,
2021operating system, image type, compression method, entry points, time
2022stamp, CRC32 checksums, etc.
wdenk24ee89b2002-11-03 17:56:27 +00002023
wdenk2729af92004-05-03 20:45:30 +00002024"mkimage" can be called in two ways: to verify existing images and
2025print the header information, or to build new images.
wdenk24ee89b2002-11-03 17:56:27 +00002026
wdenk2729af92004-05-03 20:45:30 +00002027In the first form (with "-l" option) mkimage lists the information
2028contained in the header of an existing U-Boot image; this includes
2029checksum verification:
wdenk24ee89b2002-11-03 17:56:27 +00002030
wdenk2729af92004-05-03 20:45:30 +00002031 tools/mkimage -l image
2032 -l ==> list image header information
wdenk24ee89b2002-11-03 17:56:27 +00002033
wdenk2729af92004-05-03 20:45:30 +00002034The second form (with "-d" option) is used to build a U-Boot image
2035from a "data file" which is used as image payload:
wdenk24ee89b2002-11-03 17:56:27 +00002036
wdenk2729af92004-05-03 20:45:30 +00002037 tools/mkimage -A arch -O os -T type -C comp -a addr -e ep \
2038 -n name -d data_file image
2039 -A ==> set architecture to 'arch'
2040 -O ==> set operating system to 'os'
2041 -T ==> set image type to 'type'
2042 -C ==> set compression type 'comp'
2043 -a ==> set load address to 'addr' (hex)
2044 -e ==> set entry point to 'ep' (hex)
2045 -n ==> set image name to 'name'
2046 -d ==> use image data from 'datafile'
wdenk24ee89b2002-11-03 17:56:27 +00002047
wdenk69459792004-05-29 16:53:29 +00002048Right now, all Linux kernels for PowerPC systems use the same load
2049address (0x00000000), but the entry point address depends on the
2050kernel version:
wdenkc6097192002-11-03 00:24:07 +00002051
wdenk2729af92004-05-03 20:45:30 +00002052- 2.2.x kernels have the entry point at 0x0000000C,
2053- 2.3.x and later kernels have the entry point at 0x00000000.
wdenkc6097192002-11-03 00:24:07 +00002054
wdenk2729af92004-05-03 20:45:30 +00002055So a typical call to build a U-Boot image would read:
wdenkc6097192002-11-03 00:24:07 +00002056
wdenk2729af92004-05-03 20:45:30 +00002057 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \
2058 > -A ppc -O linux -T kernel -C gzip -a 0 -e 0 \
Stefan Roesea47a12b2010-04-15 16:07:28 +02002059 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux.gz \
wdenk2729af92004-05-03 20:45:30 +00002060 > examples/uImage.TQM850L
2061 Image Name: 2.4.4 kernel for TQM850L
2062 Created: Wed Jul 19 02:34:59 2000
2063 Image Type: PowerPC Linux Kernel Image (gzip compressed)
2064 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB
2065 Load Address: 0x00000000
2066 Entry Point: 0x00000000
wdenkc6097192002-11-03 00:24:07 +00002067
wdenk2729af92004-05-03 20:45:30 +00002068To verify the contents of the image (or check for corruption):
wdenkc6097192002-11-03 00:24:07 +00002069
wdenk2729af92004-05-03 20:45:30 +00002070 -> tools/mkimage -l examples/uImage.TQM850L
2071 Image Name: 2.4.4 kernel for TQM850L
2072 Created: Wed Jul 19 02:34:59 2000
2073 Image Type: PowerPC Linux Kernel Image (gzip compressed)
2074 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB
2075 Load Address: 0x00000000
2076 Entry Point: 0x00000000
wdenkc6097192002-11-03 00:24:07 +00002077
wdenk2729af92004-05-03 20:45:30 +00002078NOTE: for embedded systems where boot time is critical you can trade
2079speed for memory and install an UNCOMPRESSED image instead: this
2080needs more space in Flash, but boots much faster since it does not
2081need to be uncompressed:
wdenkc6097192002-11-03 00:24:07 +00002082
Stefan Roesea47a12b2010-04-15 16:07:28 +02002083 -> gunzip /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux.gz
wdenk2729af92004-05-03 20:45:30 +00002084 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \
2085 > -A ppc -O linux -T kernel -C none -a 0 -e 0 \
Stefan Roesea47a12b2010-04-15 16:07:28 +02002086 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux \
wdenk2729af92004-05-03 20:45:30 +00002087 > examples/uImage.TQM850L-uncompressed
2088 Image Name: 2.4.4 kernel for TQM850L
2089 Created: Wed Jul 19 02:34:59 2000
2090 Image Type: PowerPC Linux Kernel Image (uncompressed)
2091 Data Size: 792160 Bytes = 773.59 kB = 0.76 MB
2092 Load Address: 0x00000000
2093 Entry Point: 0x00000000
wdenkc6097192002-11-03 00:24:07 +00002094
wdenkc6097192002-11-03 00:24:07 +00002095
wdenk2729af92004-05-03 20:45:30 +00002096Similar you can build U-Boot images from a 'ramdisk.image.gz' file
2097when your kernel is intended to use an initial ramdisk:
wdenkdb01a2e2004-04-15 23:14:49 +00002098
wdenk2729af92004-05-03 20:45:30 +00002099 -> tools/mkimage -n 'Simple Ramdisk Image' \
2100 > -A ppc -O linux -T ramdisk -C gzip \
2101 > -d /LinuxPPC/images/SIMPLE-ramdisk.image.gz examples/simple-initrd
2102 Image Name: Simple Ramdisk Image
2103 Created: Wed Jan 12 14:01:50 2000
2104 Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
2105 Data Size: 566530 Bytes = 553.25 kB = 0.54 MB
2106 Load Address: 0x00000000
2107 Entry Point: 0x00000000
wdenkdb01a2e2004-04-15 23:14:49 +00002108
Tyler Hickse157a112020-10-26 10:40:24 -05002109The "dumpimage" tool can be used to disassemble or list the contents of images
2110built by mkimage. See dumpimage's help output (-h) for details.
wdenkdb01a2e2004-04-15 23:14:49 +00002111
wdenk2729af92004-05-03 20:45:30 +00002112Installing a Linux Image:
2113-------------------------
wdenkdb01a2e2004-04-15 23:14:49 +00002114
wdenk2729af92004-05-03 20:45:30 +00002115To downloading a U-Boot image over the serial (console) interface,
2116you must convert the image to S-Record format:
wdenkdb01a2e2004-04-15 23:14:49 +00002117
wdenk2729af92004-05-03 20:45:30 +00002118 objcopy -I binary -O srec examples/image examples/image.srec
wdenkdb01a2e2004-04-15 23:14:49 +00002119
wdenk2729af92004-05-03 20:45:30 +00002120The 'objcopy' does not understand the information in the U-Boot
2121image header, so the resulting S-Record file will be relative to
2122address 0x00000000. To load it to a given address, you need to
2123specify the target address as 'offset' parameter with the 'loads'
2124command.
wdenkc6097192002-11-03 00:24:07 +00002125
wdenk2729af92004-05-03 20:45:30 +00002126Example: install the image to address 0x40100000 (which on the
2127TQM8xxL is in the first Flash bank):
wdenkc6097192002-11-03 00:24:07 +00002128
wdenk2729af92004-05-03 20:45:30 +00002129 => erase 40100000 401FFFFF
wdenkc6097192002-11-03 00:24:07 +00002130
wdenk2729af92004-05-03 20:45:30 +00002131 .......... done
2132 Erased 8 sectors
wdenkc6097192002-11-03 00:24:07 +00002133
wdenk2729af92004-05-03 20:45:30 +00002134 => loads 40100000
2135 ## Ready for S-Record download ...
2136 ~>examples/image.srec
2137 1 2 3 4 5 6 7 8 9 10 11 12 13 ...
2138 ...
2139 15989 15990 15991 15992
2140 [file transfer complete]
2141 [connected]
2142 ## Start Addr = 0x00000000
wdenkc6097192002-11-03 00:24:07 +00002143
2144
wdenk2729af92004-05-03 20:45:30 +00002145You can check the success of the download using the 'iminfo' command;
Wolfgang Denk218ca722008-03-26 10:40:12 +01002146this includes a checksum verification so you can be sure no data
wdenk2729af92004-05-03 20:45:30 +00002147corruption happened:
wdenkc6097192002-11-03 00:24:07 +00002148
wdenk2729af92004-05-03 20:45:30 +00002149 => imi 40100000
wdenkc6097192002-11-03 00:24:07 +00002150
wdenk2729af92004-05-03 20:45:30 +00002151 ## Checking Image at 40100000 ...
2152 Image Name: 2.2.13 for initrd on TQM850L
2153 Image Type: PowerPC Linux Kernel Image (gzip compressed)
2154 Data Size: 335725 Bytes = 327 kB = 0 MB
2155 Load Address: 00000000
2156 Entry Point: 0000000c
2157 Verifying Checksum ... OK
wdenkc6097192002-11-03 00:24:07 +00002158
2159
wdenk2729af92004-05-03 20:45:30 +00002160Boot Linux:
2161-----------
wdenkc6097192002-11-03 00:24:07 +00002162
wdenk2729af92004-05-03 20:45:30 +00002163The "bootm" command is used to boot an application that is stored in
2164memory (RAM or Flash). In case of a Linux kernel image, the contents
2165of the "bootargs" environment variable is passed to the kernel as
2166parameters. You can check and modify this variable using the
2167"printenv" and "setenv" commands:
wdenkc6097192002-11-03 00:24:07 +00002168
2169
wdenk2729af92004-05-03 20:45:30 +00002170 => printenv bootargs
2171 bootargs=root=/dev/ram
wdenkc6097192002-11-03 00:24:07 +00002172
wdenk2729af92004-05-03 20:45:30 +00002173 => setenv bootargs root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
wdenkc6097192002-11-03 00:24:07 +00002174
wdenk2729af92004-05-03 20:45:30 +00002175 => printenv bootargs
2176 bootargs=root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
wdenkc6097192002-11-03 00:24:07 +00002177
wdenk2729af92004-05-03 20:45:30 +00002178 => bootm 40020000
2179 ## Booting Linux kernel at 40020000 ...
2180 Image Name: 2.2.13 for NFS on TQM850L
2181 Image Type: PowerPC Linux Kernel Image (gzip compressed)
2182 Data Size: 381681 Bytes = 372 kB = 0 MB
2183 Load Address: 00000000
2184 Entry Point: 0000000c
2185 Verifying Checksum ... OK
2186 Uncompressing Kernel Image ... OK
2187 Linux version 2.2.13 (wd@denx.local.net) (gcc version 2.95.2 19991024 (release)) #1 Wed Jul 19 02:35:17 MEST 2000
2188 Boot arguments: root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
2189 time_init: decrementer frequency = 187500000/60
2190 Calibrating delay loop... 49.77 BogoMIPS
2191 Memory: 15208k available (700k kernel code, 444k data, 32k init) [c0000000,c1000000]
2192 ...
wdenkc6097192002-11-03 00:24:07 +00002193
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02002194If you want to boot a Linux kernel with initial RAM disk, you pass
wdenk2729af92004-05-03 20:45:30 +00002195the memory addresses of both the kernel and the initrd image (PPBCOOT
2196format!) to the "bootm" command:
wdenkc6097192002-11-03 00:24:07 +00002197
wdenk2729af92004-05-03 20:45:30 +00002198 => imi 40100000 40200000
wdenkc6097192002-11-03 00:24:07 +00002199
wdenk2729af92004-05-03 20:45:30 +00002200 ## Checking Image at 40100000 ...
2201 Image Name: 2.2.13 for initrd on TQM850L
2202 Image Type: PowerPC Linux Kernel Image (gzip compressed)
2203 Data Size: 335725 Bytes = 327 kB = 0 MB
2204 Load Address: 00000000
2205 Entry Point: 0000000c
2206 Verifying Checksum ... OK
wdenkc6097192002-11-03 00:24:07 +00002207
wdenk2729af92004-05-03 20:45:30 +00002208 ## Checking Image at 40200000 ...
2209 Image Name: Simple Ramdisk Image
2210 Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
2211 Data Size: 566530 Bytes = 553 kB = 0 MB
2212 Load Address: 00000000
2213 Entry Point: 00000000
2214 Verifying Checksum ... OK
wdenkc6097192002-11-03 00:24:07 +00002215
wdenk2729af92004-05-03 20:45:30 +00002216 => bootm 40100000 40200000
2217 ## Booting Linux kernel at 40100000 ...
2218 Image Name: 2.2.13 for initrd on TQM850L
2219 Image Type: PowerPC Linux Kernel Image (gzip compressed)
2220 Data Size: 335725 Bytes = 327 kB = 0 MB
2221 Load Address: 00000000
2222 Entry Point: 0000000c
2223 Verifying Checksum ... OK
2224 Uncompressing Kernel Image ... OK
2225 ## Loading RAMDisk Image at 40200000 ...
2226 Image Name: Simple Ramdisk Image
2227 Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
2228 Data Size: 566530 Bytes = 553 kB = 0 MB
2229 Load Address: 00000000
2230 Entry Point: 00000000
2231 Verifying Checksum ... OK
2232 Loading Ramdisk ... OK
2233 Linux version 2.2.13 (wd@denx.local.net) (gcc version 2.95.2 19991024 (release)) #1 Wed Jul 19 02:32:08 MEST 2000
2234 Boot arguments: root=/dev/ram
2235 time_init: decrementer frequency = 187500000/60
2236 Calibrating delay loop... 49.77 BogoMIPS
2237 ...
2238 RAMDISK: Compressed image found at block 0
2239 VFS: Mounted root (ext2 filesystem).
wdenkc6097192002-11-03 00:24:07 +00002240
wdenk2729af92004-05-03 20:45:30 +00002241 bash#
wdenkc6097192002-11-03 00:24:07 +00002242
Matthew McClintock02677682006-06-28 10:41:37 -05002243Boot Linux and pass a flat device tree:
2244-----------
2245
2246First, U-Boot must be compiled with the appropriate defines. See the section
2247titled "Linux Kernel Interface" above for a more in depth explanation. The
2248following is an example of how to start a kernel and pass an updated
2249flat device tree:
2250
2251=> print oftaddr
2252oftaddr=0x300000
2253=> print oft
2254oft=oftrees/mpc8540ads.dtb
2255=> tftp $oftaddr $oft
2256Speed: 1000, full duplex
2257Using TSEC0 device
2258TFTP from server 192.168.1.1; our IP address is 192.168.1.101
2259Filename 'oftrees/mpc8540ads.dtb'.
2260Load address: 0x300000
2261Loading: #
2262done
2263Bytes transferred = 4106 (100a hex)
2264=> tftp $loadaddr $bootfile
2265Speed: 1000, full duplex
2266Using TSEC0 device
2267TFTP from server 192.168.1.1; our IP address is 192.168.1.2
2268Filename 'uImage'.
2269Load address: 0x200000
2270Loading:############
2271done
2272Bytes transferred = 1029407 (fb51f hex)
2273=> print loadaddr
2274loadaddr=200000
2275=> print oftaddr
2276oftaddr=0x300000
2277=> bootm $loadaddr - $oftaddr
2278## Booting image at 00200000 ...
Wolfgang Denka9398e02006-11-27 15:32:42 +01002279 Image Name: Linux-2.6.17-dirty
2280 Image Type: PowerPC Linux Kernel Image (gzip compressed)
2281 Data Size: 1029343 Bytes = 1005.2 kB
Matthew McClintock02677682006-06-28 10:41:37 -05002282 Load Address: 00000000
Wolfgang Denka9398e02006-11-27 15:32:42 +01002283 Entry Point: 00000000
Matthew McClintock02677682006-06-28 10:41:37 -05002284 Verifying Checksum ... OK
2285 Uncompressing Kernel Image ... OK
2286Booting using flat device tree at 0x300000
2287Using MPC85xx ADS machine description
2288Memory CAM mapping: CAM0=256Mb, CAM1=256Mb, CAM2=0Mb residual: 0Mb
2289[snip]
2290
2291
wdenk2729af92004-05-03 20:45:30 +00002292More About U-Boot Image Types:
2293------------------------------
wdenk6069ff22003-02-28 00:49:47 +00002294
wdenk2729af92004-05-03 20:45:30 +00002295U-Boot supports the following image types:
wdenk6069ff22003-02-28 00:49:47 +00002296
wdenk2729af92004-05-03 20:45:30 +00002297 "Standalone Programs" are directly runnable in the environment
2298 provided by U-Boot; it is expected that (if they behave
2299 well) you can continue to work in U-Boot after return from
2300 the Standalone Program.
2301 "OS Kernel Images" are usually images of some Embedded OS which
2302 will take over control completely. Usually these programs
2303 will install their own set of exception handlers, device
2304 drivers, set up the MMU, etc. - this means, that you cannot
2305 expect to re-enter U-Boot except by resetting the CPU.
2306 "RAMDisk Images" are more or less just data blocks, and their
2307 parameters (address, size) are passed to an OS kernel that is
2308 being started.
2309 "Multi-File Images" contain several images, typically an OS
2310 (Linux) kernel image and one or more data images like
2311 RAMDisks. This construct is useful for instance when you want
2312 to boot over the network using BOOTP etc., where the boot
2313 server provides just a single image file, but you want to get
2314 for instance an OS kernel and a RAMDisk image.
stroesec1551ea2003-04-04 15:53:41 +00002315
wdenk2729af92004-05-03 20:45:30 +00002316 "Multi-File Images" start with a list of image sizes, each
2317 image size (in bytes) specified by an "uint32_t" in network
2318 byte order. This list is terminated by an "(uint32_t)0".
2319 Immediately after the terminating 0 follow the images, one by
2320 one, all aligned on "uint32_t" boundaries (size rounded up to
2321 a multiple of 4 bytes).
stroesec1551ea2003-04-04 15:53:41 +00002322
wdenk2729af92004-05-03 20:45:30 +00002323 "Firmware Images" are binary images containing firmware (like
2324 U-Boot or FPGA images) which usually will be programmed to
2325 flash memory.
stroesec1551ea2003-04-04 15:53:41 +00002326
wdenk2729af92004-05-03 20:45:30 +00002327 "Script files" are command sequences that will be executed by
2328 U-Boot's command interpreter; this feature is especially
2329 useful when you configure U-Boot to use a real shell (hush)
2330 as command interpreter.
wdenk6069ff22003-02-28 00:49:47 +00002331
Marek Vasut44f074c2012-03-14 21:52:45 +00002332Booting the Linux zImage:
2333-------------------------
2334
2335On some platforms, it's possible to boot Linux zImage. This is done
2336using the "bootz" command. The syntax of "bootz" command is the same
2337as the syntax of "bootm" command.
2338
Tom Rini8ac28562013-05-16 11:40:11 -04002339Note, defining the CONFIG_SUPPORT_RAW_INITRD allows user to supply
Marek Vasut017e1f32012-03-18 11:47:58 +00002340kernel with raw initrd images. The syntax is slightly different, the
2341address of the initrd must be augmented by it's size, in the following
2342format: "<initrd addres>:<initrd size>".
2343
wdenkc6097192002-11-03 00:24:07 +00002344
wdenk2729af92004-05-03 20:45:30 +00002345Standalone HOWTO:
2346=================
wdenkc6097192002-11-03 00:24:07 +00002347
wdenk2729af92004-05-03 20:45:30 +00002348One of the features of U-Boot is that you can dynamically load and
2349run "standalone" applications, which can use some resources of
2350U-Boot like console I/O functions or interrupt services.
wdenkc6097192002-11-03 00:24:07 +00002351
wdenk2729af92004-05-03 20:45:30 +00002352Two simple examples are included with the sources:
wdenkc6097192002-11-03 00:24:07 +00002353
wdenk2729af92004-05-03 20:45:30 +00002354"Hello World" Demo:
2355-------------------
wdenkc6097192002-11-03 00:24:07 +00002356
wdenk2729af92004-05-03 20:45:30 +00002357'examples/hello_world.c' contains a small "Hello World" Demo
2358application; it is automatically compiled when you build U-Boot.
2359It's configured to run at address 0x00040004, so you can play with it
2360like that:
wdenkc6097192002-11-03 00:24:07 +00002361
wdenk2729af92004-05-03 20:45:30 +00002362 => loads
2363 ## Ready for S-Record download ...
2364 ~>examples/hello_world.srec
2365 1 2 3 4 5 6 7 8 9 10 11 ...
2366 [file transfer complete]
2367 [connected]
2368 ## Start Addr = 0x00040004
wdenkc6097192002-11-03 00:24:07 +00002369
wdenk2729af92004-05-03 20:45:30 +00002370 => go 40004 Hello World! This is a test.
2371 ## Starting application at 0x00040004 ...
2372 Hello World
2373 argc = 7
2374 argv[0] = "40004"
2375 argv[1] = "Hello"
2376 argv[2] = "World!"
2377 argv[3] = "This"
2378 argv[4] = "is"
2379 argv[5] = "a"
2380 argv[6] = "test."
2381 argv[7] = "<NULL>"
2382 Hit any key to exit ...
wdenkc6097192002-11-03 00:24:07 +00002383
wdenk2729af92004-05-03 20:45:30 +00002384 ## Application terminated, rc = 0x0
wdenkc6097192002-11-03 00:24:07 +00002385
wdenk2729af92004-05-03 20:45:30 +00002386Another example, which demonstrates how to register a CPM interrupt
2387handler with the U-Boot code, can be found in 'examples/timer.c'.
2388Here, a CPM timer is set up to generate an interrupt every second.
2389The interrupt service routine is trivial, just printing a '.'
2390character, but this is just a demo program. The application can be
2391controlled by the following keys:
wdenkc6097192002-11-03 00:24:07 +00002392
wdenk2729af92004-05-03 20:45:30 +00002393 ? - print current values og the CPM Timer registers
2394 b - enable interrupts and start timer
2395 e - stop timer and disable interrupts
2396 q - quit application
wdenkc6097192002-11-03 00:24:07 +00002397
wdenk2729af92004-05-03 20:45:30 +00002398 => loads
2399 ## Ready for S-Record download ...
2400 ~>examples/timer.srec
2401 1 2 3 4 5 6 7 8 9 10 11 ...
2402 [file transfer complete]
2403 [connected]
2404 ## Start Addr = 0x00040004
wdenkc6097192002-11-03 00:24:07 +00002405
wdenk2729af92004-05-03 20:45:30 +00002406 => go 40004
2407 ## Starting application at 0x00040004 ...
2408 TIMERS=0xfff00980
2409 Using timer 1
2410 tgcr @ 0xfff00980, tmr @ 0xfff00990, trr @ 0xfff00994, tcr @ 0xfff00998, tcn @ 0xfff0099c, ter @ 0xfff009b0
wdenkc6097192002-11-03 00:24:07 +00002411
wdenk2729af92004-05-03 20:45:30 +00002412Hit 'b':
2413 [q, b, e, ?] Set interval 1000000 us
2414 Enabling timer
2415Hit '?':
2416 [q, b, e, ?] ........
2417 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0xef6, ter=0x0
2418Hit '?':
2419 [q, b, e, ?] .
2420 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x2ad4, ter=0x0
2421Hit '?':
2422 [q, b, e, ?] .
2423 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x1efc, ter=0x0
2424Hit '?':
2425 [q, b, e, ?] .
2426 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x169d, ter=0x0
2427Hit 'e':
2428 [q, b, e, ?] ...Stopping timer
2429Hit 'q':
2430 [q, b, e, ?] ## Application terminated, rc = 0x0
wdenkc6097192002-11-03 00:24:07 +00002431
2432
wdenk2729af92004-05-03 20:45:30 +00002433Minicom warning:
2434================
wdenk85ec0bc2003-03-31 16:34:49 +00002435
wdenk2729af92004-05-03 20:45:30 +00002436Over time, many people have reported problems when trying to use the
2437"minicom" terminal emulation program for serial download. I (wd)
2438consider minicom to be broken, and recommend not to use it. Under
2439Unix, I recommend to use C-Kermit for general purpose use (and
2440especially for kermit binary protocol download ("loadb" command), and
Karl O. Pince53515a2012-10-01 05:11:56 +00002441use "cu" for S-Record download ("loads" command). See
Naoki Hayama047f6ec2020-10-08 13:17:16 +09002442https://www.denx.de/wiki/view/DULG/SystemSetup#Section_4.3.
Karl O. Pince53515a2012-10-01 05:11:56 +00002443for help with kermit.
2444
wdenk85ec0bc2003-03-31 16:34:49 +00002445
wdenk2729af92004-05-03 20:45:30 +00002446Nevertheless, if you absolutely want to use it try adding this
2447configuration to your "File transfer protocols" section:
wdenk52f52c12003-06-19 23:04:19 +00002448
wdenk2729af92004-05-03 20:45:30 +00002449 Name Program Name U/D FullScr IO-Red. Multi
2450 X kermit /usr/bin/kermit -i -l %l -s Y U Y N N
2451 Y kermit /usr/bin/kermit -i -l %l -r N D Y N N
wdenk52f52c12003-06-19 23:04:19 +00002452
2453
wdenk2729af92004-05-03 20:45:30 +00002454Implementation Internals:
2455=========================
wdenkc6097192002-11-03 00:24:07 +00002456
wdenk2729af92004-05-03 20:45:30 +00002457The following is not intended to be a complete description of every
2458implementation detail. However, it should help to understand the
2459inner workings of U-Boot and make it easier to port it to custom
2460hardware.
wdenkc6097192002-11-03 00:24:07 +00002461
2462
wdenk2729af92004-05-03 20:45:30 +00002463Initial Stack, Global Data:
2464---------------------------
wdenkc6097192002-11-03 00:24:07 +00002465
wdenk2729af92004-05-03 20:45:30 +00002466The implementation of U-Boot is complicated by the fact that U-Boot
2467starts running out of ROM (flash memory), usually without access to
2468system RAM (because the memory controller is not initialized yet).
2469This means that we don't have writable Data or BSS segments, and BSS
2470is not initialized as zero. To be able to get a C environment working
2471at all, we have to allocate at least a minimal stack. Implementation
2472options for this are defined and restricted by the CPU used: Some CPU
2473models provide on-chip memory (like the IMMR area on MPC8xx and
2474MPC826x processors), on others (parts of) the data cache can be
2475locked as (mis-) used as memory, etc.
wdenkc6097192002-11-03 00:24:07 +00002476
Wolfgang Denk218ca722008-03-26 10:40:12 +01002477 Chris Hallinan posted a good summary of these issues to the
Wolfgang Denk06682362008-12-30 22:56:11 +01002478 U-Boot mailing list:
wdenk43d96162003-03-06 00:02:04 +00002479
wdenk2729af92004-05-03 20:45:30 +00002480 Subject: RE: [U-Boot-Users] RE: More On Memory Bank x (nothingness)?
2481 From: "Chris Hallinan" <clh@net1plus.com>
2482 Date: Mon, 10 Feb 2003 16:43:46 -0500 (22:43 MET)
2483 ...
wdenk43d96162003-03-06 00:02:04 +00002484
wdenk2729af92004-05-03 20:45:30 +00002485 Correct me if I'm wrong, folks, but the way I understand it
2486 is this: Using DCACHE as initial RAM for Stack, etc, does not
2487 require any physical RAM backing up the cache. The cleverness
2488 is that the cache is being used as a temporary supply of
2489 necessary storage before the SDRAM controller is setup. It's
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02002490 beyond the scope of this list to explain the details, but you
wdenk2729af92004-05-03 20:45:30 +00002491 can see how this works by studying the cache architecture and
2492 operation in the architecture and processor-specific manuals.
wdenk43d96162003-03-06 00:02:04 +00002493
wdenk2729af92004-05-03 20:45:30 +00002494 OCM is On Chip Memory, which I believe the 405GP has 4K. It
2495 is another option for the system designer to use as an
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02002496 initial stack/RAM area prior to SDRAM being available. Either
wdenk2729af92004-05-03 20:45:30 +00002497 option should work for you. Using CS 4 should be fine if your
2498 board designers haven't used it for something that would
2499 cause you grief during the initial boot! It is frequently not
2500 used.
wdenk43d96162003-03-06 00:02:04 +00002501
Tom Rini65cc0e22022-11-16 13:10:41 -05002502 CFG_SYS_INIT_RAM_ADDR should be somewhere that won't interfere
wdenk2729af92004-05-03 20:45:30 +00002503 with your processor/board/system design. The default value
2504 you will find in any recent u-boot distribution in
Stefan Roese8a316c92005-08-01 16:49:12 +02002505 walnut.h should work for you. I'd set it to a value larger
wdenk2729af92004-05-03 20:45:30 +00002506 than your SDRAM module. If you have a 64MB SDRAM module, set
2507 it above 400_0000. Just make sure your board has no resources
2508 that are supposed to respond to that address! That code in
2509 start.S has been around a while and should work as is when
2510 you get the config right.
wdenk43d96162003-03-06 00:02:04 +00002511
wdenk2729af92004-05-03 20:45:30 +00002512 -Chris Hallinan
2513 DS4.COM, Inc.
wdenk43d96162003-03-06 00:02:04 +00002514
wdenk2729af92004-05-03 20:45:30 +00002515It is essential to remember this, since it has some impact on the C
2516code for the initialization procedures:
wdenkc6097192002-11-03 00:24:07 +00002517
wdenk2729af92004-05-03 20:45:30 +00002518* Initialized global data (data segment) is read-only. Do not attempt
2519 to write it.
wdenkc6097192002-11-03 00:24:07 +00002520
Jeremiah Mahlerb445bbb2015-01-04 18:56:50 -08002521* Do not use any uninitialized global data (or implicitly initialized
wdenk2729af92004-05-03 20:45:30 +00002522 as zero data - BSS segment) at all - this is undefined, initiali-
2523 zation is performed later (when relocating to RAM).
wdenkc6097192002-11-03 00:24:07 +00002524
wdenk2729af92004-05-03 20:45:30 +00002525* Stack space is very limited. Avoid big data buffers or things like
2526 that.
wdenkc6097192002-11-03 00:24:07 +00002527
wdenk2729af92004-05-03 20:45:30 +00002528Having only the stack as writable memory limits means we cannot use
Jeremiah Mahlerb445bbb2015-01-04 18:56:50 -08002529normal global data to share information between the code. But it
wdenk2729af92004-05-03 20:45:30 +00002530turned out that the implementation of U-Boot can be greatly
2531simplified by making a global data structure (gd_t) available to all
2532functions. We could pass a pointer to this data as argument to _all_
2533functions, but this would bloat the code. Instead we use a feature of
2534the GCC compiler (Global Register Variables) to share the data: we
2535place a pointer (gd) to the global data into a register which we
2536reserve for this purpose.
wdenkc6097192002-11-03 00:24:07 +00002537
wdenk2729af92004-05-03 20:45:30 +00002538When choosing a register for such a purpose we are restricted by the
2539relevant (E)ABI specifications for the current architecture, and by
2540GCC's implementation.
wdenkc6097192002-11-03 00:24:07 +00002541
wdenk2729af92004-05-03 20:45:30 +00002542For PowerPC, the following registers have specific use:
2543 R1: stack pointer
Wolfgang Denke7670f62008-02-14 22:43:22 +01002544 R2: reserved for system use
wdenk2729af92004-05-03 20:45:30 +00002545 R3-R4: parameter passing and return values
2546 R5-R10: parameter passing
2547 R13: small data area pointer
2548 R30: GOT pointer
2549 R31: frame pointer
wdenkc6097192002-11-03 00:24:07 +00002550
Joakim Tjernlunde6bee802010-01-19 14:41:58 +01002551 (U-Boot also uses R12 as internal GOT pointer. r12
2552 is a volatile register so r12 needs to be reset when
2553 going back and forth between asm and C)
wdenkc6097192002-11-03 00:24:07 +00002554
Wolfgang Denke7670f62008-02-14 22:43:22 +01002555 ==> U-Boot will use R2 to hold a pointer to the global data
wdenkc6097192002-11-03 00:24:07 +00002556
wdenk2729af92004-05-03 20:45:30 +00002557 Note: on PPC, we could use a static initializer (since the
2558 address of the global data structure is known at compile time),
2559 but it turned out that reserving a register results in somewhat
2560 smaller code - although the code savings are not that big (on
2561 average for all boards 752 bytes for the whole U-Boot image,
2562 624 text + 127 data).
wdenkc6097192002-11-03 00:24:07 +00002563
wdenk2729af92004-05-03 20:45:30 +00002564On ARM, the following registers are used:
wdenkc6097192002-11-03 00:24:07 +00002565
wdenk2729af92004-05-03 20:45:30 +00002566 R0: function argument word/integer result
2567 R1-R3: function argument word
Jeroen Hofstee12eba1b2013-09-21 14:04:42 +02002568 R9: platform specific
2569 R10: stack limit (used only if stack checking is enabled)
wdenk2729af92004-05-03 20:45:30 +00002570 R11: argument (frame) pointer
2571 R12: temporary workspace
2572 R13: stack pointer
2573 R14: link register
2574 R15: program counter
wdenkc6097192002-11-03 00:24:07 +00002575
Jeroen Hofstee12eba1b2013-09-21 14:04:42 +02002576 ==> U-Boot will use R9 to hold a pointer to the global data
2577
2578 Note: on ARM, only R_ARM_RELATIVE relocations are supported.
wdenkc6097192002-11-03 00:24:07 +00002579
Thomas Chou0df01fd32010-05-21 11:08:03 +08002580On Nios II, the ABI is documented here:
Naoki Hayama047f6ec2020-10-08 13:17:16 +09002581 https://www.altera.com/literature/hb/nios2/n2cpu_nii51016.pdf
Thomas Chou0df01fd32010-05-21 11:08:03 +08002582
2583 ==> U-Boot will use gp to hold a pointer to the global data
2584
2585 Note: on Nios II, we give "-G0" option to gcc and don't use gp
2586 to access small data sections, so gp is free.
2587
Rick Chen3fafced2017-12-26 13:55:59 +08002588On RISC-V, the following registers are used:
2589
2590 x0: hard-wired zero (zero)
2591 x1: return address (ra)
2592 x2: stack pointer (sp)
2593 x3: global pointer (gp)
2594 x4: thread pointer (tp)
2595 x5: link register (t0)
2596 x8: frame pointer (fp)
2597 x10-x11: arguments/return values (a0-1)
2598 x12-x17: arguments (a2-7)
2599 x28-31: temporaries (t3-6)
2600 pc: program counter (pc)
2601
2602 ==> U-Boot will use gp to hold a pointer to the global data
2603
wdenk2729af92004-05-03 20:45:30 +00002604Memory Management:
2605------------------
wdenkc6097192002-11-03 00:24:07 +00002606
wdenk2729af92004-05-03 20:45:30 +00002607U-Boot runs in system state and uses physical addresses, i.e. the
2608MMU is not used either for address mapping nor for memory protection.
wdenkc6097192002-11-03 00:24:07 +00002609
wdenk2729af92004-05-03 20:45:30 +00002610The available memory is mapped to fixed addresses using the memory
2611controller. In this process, a contiguous block is formed for each
2612memory type (Flash, SDRAM, SRAM), even when it consists of several
2613physical memory banks.
wdenkc6097192002-11-03 00:24:07 +00002614
wdenk2729af92004-05-03 20:45:30 +00002615U-Boot is installed in the first 128 kB of the first Flash bank (on
2616TQM8xxL modules this is the range 0x40000000 ... 0x4001FFFF). After
2617booting and sizing and initializing DRAM, the code relocates itself
2618to the upper end of DRAM. Immediately below the U-Boot code some
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +02002619memory is reserved for use by malloc() [see CONFIG_SYS_MALLOC_LEN
wdenk2729af92004-05-03 20:45:30 +00002620configuration setting]. Below that, a structure with global Board
2621Info data is placed, followed by the stack (growing downward).
wdenkc6097192002-11-03 00:24:07 +00002622
wdenk2729af92004-05-03 20:45:30 +00002623Additionally, some exception handler code is copied to the low 8 kB
2624of DRAM (0x00000000 ... 0x00001FFF).
wdenkc6097192002-11-03 00:24:07 +00002625
wdenk2729af92004-05-03 20:45:30 +00002626So a typical memory configuration with 16 MB of DRAM could look like
2627this:
wdenkc6097192002-11-03 00:24:07 +00002628
wdenk2729af92004-05-03 20:45:30 +00002629 0x0000 0000 Exception Vector code
2630 :
2631 0x0000 1FFF
2632 0x0000 2000 Free for Application Use
2633 :
2634 :
wdenkc6097192002-11-03 00:24:07 +00002635
wdenk2729af92004-05-03 20:45:30 +00002636 :
2637 :
2638 0x00FB FF20 Monitor Stack (Growing downward)
2639 0x00FB FFAC Board Info Data and permanent copy of global data
2640 0x00FC 0000 Malloc Arena
2641 :
2642 0x00FD FFFF
2643 0x00FE 0000 RAM Copy of Monitor Code
2644 ... eventually: LCD or video framebuffer
2645 ... eventually: pRAM (Protected RAM - unchanged by reset)
2646 0x00FF FFFF [End of RAM]
wdenkc6097192002-11-03 00:24:07 +00002647
2648
wdenk2729af92004-05-03 20:45:30 +00002649System Initialization:
2650----------------------
wdenkc6097192002-11-03 00:24:07 +00002651
wdenk2729af92004-05-03 20:45:30 +00002652In the reset configuration, U-Boot starts at the reset entry point
Marcel Ziswiler11ccc332008-07-09 08:17:15 +02002653(on most PowerPC systems at address 0x00000100). Because of the reset
Jeremiah Mahlerb445bbb2015-01-04 18:56:50 -08002654configuration for CS0# this is a mirror of the on board Flash memory.
wdenk2729af92004-05-03 20:45:30 +00002655To be able to re-map memory U-Boot then jumps to its link address.
2656To be able to implement the initialization code in C, a (small!)
2657initial stack is set up in the internal Dual Ported RAM (in case CPUs
Heiko Schocher2eb48ff2017-06-07 17:33:10 +02002658which provide such a feature like), or in a locked part of the data
2659cache. After that, U-Boot initializes the CPU core, the caches and
2660the SIU.
wdenkc6097192002-11-03 00:24:07 +00002661
wdenk2729af92004-05-03 20:45:30 +00002662Next, all (potentially) available memory banks are mapped using a
2663preliminary mapping. For example, we put them on 512 MB boundaries
2664(multiples of 0x20000000: SDRAM on 0x00000000 and 0x20000000, Flash
2665on 0x40000000 and 0x60000000, SRAM on 0x80000000). Then UPM A is
2666programmed for SDRAM access. Using the temporary configuration, a
2667simple memory test is run that determines the size of the SDRAM
2668banks.
wdenkc6097192002-11-03 00:24:07 +00002669
wdenk2729af92004-05-03 20:45:30 +00002670When there is more than one SDRAM bank, and the banks are of
2671different size, the largest is mapped first. For equal size, the first
2672bank (CS2#) is mapped first. The first mapping is always for address
26730x00000000, with any additional banks following immediately to create
2674contiguous memory starting from 0.
wdenkc6097192002-11-03 00:24:07 +00002675
wdenk2729af92004-05-03 20:45:30 +00002676Then, the monitor installs itself at the upper end of the SDRAM area
2677and allocates memory for use by malloc() and for the global Board
2678Info data; also, the exception vector code is copied to the low RAM
2679pages, and the final stack is set up.
wdenkc6097192002-11-03 00:24:07 +00002680
wdenk2729af92004-05-03 20:45:30 +00002681Only after this relocation will you have a "normal" C environment;
2682until that you are restricted in several ways, mostly because you are
2683running from ROM, and because the code will have to be relocated to a
2684new address in RAM.
wdenkc6097192002-11-03 00:24:07 +00002685
2686
Heinrich Schuchardt1405bfd2023-01-25 19:14:57 +01002687Contributing
2688============
wdenkc6097192002-11-03 00:24:07 +00002689
Heinrich Schuchardt1405bfd2023-01-25 19:14:57 +01002690The U-Boot projects depends on contributions from the user community.
2691If you want to participate, please, have a look at the 'General'
2692section of https://u-boot.readthedocs.io/en/latest/develop/index.html
2693where we describe coding standards and the patch submission process.