2 # (C) Copyright 2000 - 2012
3 # Wolfgang Denk, DENX Software Engineering, wd@denx.de.
5 # See file CREDITS for list of people who contributed to this
8 # This program is free software; you can redistribute it and/or
9 # modify it under the terms of the GNU General Public License as
10 # published by the Free Software Foundation; either version 2 of
11 # the License, or (at your option) any later version.
13 # This program is distributed in the hope that it will be useful,
14 # but WITHOUT ANY WARRANTY; without even the implied warranty of
15 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 # GNU General Public License for more details.
18 # You should have received a copy of the GNU General Public License
19 # along with this program; if not, write to the Free Software
20 # Foundation, Inc., 59 Temple Place, Suite 330, Boston,
27 This directory contains the source code for U-Boot, a boot loader for
28 Embedded boards based on PowerPC, ARM, MIPS and several other
29 processors, which can be installed in a boot ROM and used to
30 initialize and test the hardware or to download and run application
33 The development of U-Boot is closely related to Linux: some parts of
34 the source code originate in the Linux source tree, we have some
35 header files in common, and special provision has been made to
36 support booting of Linux images.
38 Some attention has been paid to make this software easily
39 configurable and extendable. For instance, all monitor commands are
40 implemented with the same call interface, so that it's very easy to
41 add new commands. Also, instead of permanently adding rarely used
42 code (for instance hardware test utilities) to the monitor, you can
43 load and run it dynamically.
49 In general, all boards for which a configuration option exists in the
50 Makefile have been tested to some extent and can be considered
51 "working". In fact, many of them are used in production systems.
53 In case of problems see the CHANGELOG and CREDITS files to find out
54 who contributed the specific port. The MAINTAINERS file lists board
57 Note: There is no CHANGELOG file in the actual U-Boot source tree;
58 it can be created dynamically from the Git log using:
66 In case you have questions about, problems with or contributions for
67 U-Boot you should send a message to the U-Boot mailing list at
68 <u-boot@lists.denx.de>. There is also an archive of previous traffic
69 on the mailing list - please search the archive before asking FAQ's.
70 Please see http://lists.denx.de/pipermail/u-boot and
71 http://dir.gmane.org/gmane.comp.boot-loaders.u-boot
74 Where to get source code:
75 =========================
77 The U-Boot source code is maintained in the git repository at
78 git://www.denx.de/git/u-boot.git ; you can browse it online at
79 http://www.denx.de/cgi-bin/gitweb.cgi?p=u-boot.git;a=summary
81 The "snapshot" links on this page allow you to download tarballs of
82 any version you might be interested in. Official releases are also
83 available for FTP download from the ftp://ftp.denx.de/pub/u-boot/
86 Pre-built (and tested) images are available from
87 ftp://ftp.denx.de/pub/u-boot/images/
93 - start from 8xxrom sources
94 - create PPCBoot project (http://sourceforge.net/projects/ppcboot)
96 - make it easier to add custom boards
97 - make it possible to add other [PowerPC] CPUs
98 - extend functions, especially:
99 * Provide extended interface to Linux boot loader
102 * PCMCIA / CompactFlash / ATA disk / SCSI ... boot
103 - create ARMBoot project (http://sourceforge.net/projects/armboot)
104 - add other CPU families (starting with ARM)
105 - create U-Boot project (http://sourceforge.net/projects/u-boot)
106 - current project page: see http://www.denx.de/wiki/U-Boot
112 The "official" name of this project is "Das U-Boot". The spelling
113 "U-Boot" shall be used in all written text (documentation, comments
114 in source files etc.). Example:
116 This is the README file for the U-Boot project.
118 File names etc. shall be based on the string "u-boot". Examples:
120 include/asm-ppc/u-boot.h
122 #include <asm/u-boot.h>
124 Variable names, preprocessor constants etc. shall be either based on
125 the string "u_boot" or on "U_BOOT". Example:
127 U_BOOT_VERSION u_boot_logo
128 IH_OS_U_BOOT u_boot_hush_start
134 Starting with the release in October 2008, the names of the releases
135 were changed from numerical release numbers without deeper meaning
136 into a time stamp based numbering. Regular releases are identified by
137 names consisting of the calendar year and month of the release date.
138 Additional fields (if present) indicate release candidates or bug fix
139 releases in "stable" maintenance trees.
142 U-Boot v2009.11 - Release November 2009
143 U-Boot v2009.11.1 - Release 1 in version November 2009 stable tree
144 U-Boot v2010.09-rc1 - Release candiate 1 for September 2010 release
150 /arch Architecture specific files
151 /arm Files generic to ARM architecture
152 /cpu CPU specific files
153 /arm720t Files specific to ARM 720 CPUs
154 /arm920t Files specific to ARM 920 CPUs
155 /at91 Files specific to Atmel AT91RM9200 CPU
156 /imx Files specific to Freescale MC9328 i.MX CPUs
157 /s3c24x0 Files specific to Samsung S3C24X0 CPUs
158 /arm925t Files specific to ARM 925 CPUs
159 /arm926ejs Files specific to ARM 926 CPUs
160 /arm1136 Files specific to ARM 1136 CPUs
161 /ixp Files specific to Intel XScale IXP CPUs
162 /pxa Files specific to Intel XScale PXA CPUs
163 /s3c44b0 Files specific to Samsung S3C44B0 CPUs
164 /sa1100 Files specific to Intel StrongARM SA1100 CPUs
165 /lib Architecture specific library files
166 /avr32 Files generic to AVR32 architecture
167 /cpu CPU specific files
168 /lib Architecture specific library files
169 /blackfin Files generic to Analog Devices Blackfin architecture
170 /cpu CPU specific files
171 /lib Architecture specific library files
172 /x86 Files generic to x86 architecture
173 /cpu CPU specific files
174 /lib Architecture specific library files
175 /m68k Files generic to m68k architecture
176 /cpu CPU specific files
177 /mcf52x2 Files specific to Freescale ColdFire MCF52x2 CPUs
178 /mcf5227x Files specific to Freescale ColdFire MCF5227x CPUs
179 /mcf532x Files specific to Freescale ColdFire MCF5329 CPUs
180 /mcf5445x Files specific to Freescale ColdFire MCF5445x CPUs
181 /mcf547x_8x Files specific to Freescale ColdFire MCF547x_8x CPUs
182 /lib Architecture specific library files
183 /microblaze Files generic to microblaze architecture
184 /cpu CPU specific files
185 /lib Architecture specific library files
186 /mips Files generic to MIPS architecture
187 /cpu CPU specific files
188 /mips32 Files specific to MIPS32 CPUs
189 /xburst Files specific to Ingenic XBurst CPUs
190 /lib Architecture specific library files
191 /nds32 Files generic to NDS32 architecture
192 /cpu CPU specific files
193 /n1213 Files specific to Andes Technology N1213 CPUs
194 /lib Architecture specific library files
195 /nios2 Files generic to Altera NIOS2 architecture
196 /cpu CPU specific files
197 /lib Architecture specific library files
198 /powerpc Files generic to PowerPC architecture
199 /cpu CPU specific files
200 /74xx_7xx Files specific to Freescale MPC74xx and 7xx CPUs
201 /mpc5xx Files specific to Freescale MPC5xx CPUs
202 /mpc5xxx Files specific to Freescale MPC5xxx CPUs
203 /mpc8xx Files specific to Freescale MPC8xx CPUs
204 /mpc8220 Files specific to Freescale MPC8220 CPUs
205 /mpc824x Files specific to Freescale MPC824x CPUs
206 /mpc8260 Files specific to Freescale MPC8260 CPUs
207 /mpc85xx Files specific to Freescale MPC85xx CPUs
208 /ppc4xx Files specific to AMCC PowerPC 4xx CPUs
209 /lib Architecture specific library files
210 /sh Files generic to SH architecture
211 /cpu CPU specific files
212 /sh2 Files specific to sh2 CPUs
213 /sh3 Files specific to sh3 CPUs
214 /sh4 Files specific to sh4 CPUs
215 /lib Architecture specific library files
216 /sparc Files generic to SPARC architecture
217 /cpu CPU specific files
218 /leon2 Files specific to Gaisler LEON2 SPARC CPU
219 /leon3 Files specific to Gaisler LEON3 SPARC CPU
220 /lib Architecture specific library files
221 /api Machine/arch independent API for external apps
222 /board Board dependent files
223 /common Misc architecture independent functions
224 /disk Code for disk drive partition handling
225 /doc Documentation (don't expect too much)
226 /drivers Commonly used device drivers
227 /examples Example code for standalone applications, etc.
228 /fs Filesystem code (cramfs, ext2, jffs2, etc.)
229 /include Header Files
230 /lib Files generic to all architectures
231 /libfdt Library files to support flattened device trees
232 /lzma Library files to support LZMA decompression
233 /lzo Library files to support LZO decompression
235 /post Power On Self Test
236 /rtc Real Time Clock drivers
237 /tools Tools to build S-Record or U-Boot images, etc.
239 Software Configuration:
240 =======================
242 Configuration is usually done using C preprocessor defines; the
243 rationale behind that is to avoid dead code whenever possible.
245 There are two classes of configuration variables:
247 * Configuration _OPTIONS_:
248 These are selectable by the user and have names beginning with
251 * Configuration _SETTINGS_:
252 These depend on the hardware etc. and should not be meddled with if
253 you don't know what you're doing; they have names beginning with
256 Later we will add a configuration tool - probably similar to or even
257 identical to what's used for the Linux kernel. Right now, we have to
258 do the configuration by hand, which means creating some symbolic
259 links and editing some configuration files. We use the TQM8xxL boards
263 Selection of Processor Architecture and Board Type:
264 ---------------------------------------------------
266 For all supported boards there are ready-to-use default
267 configurations available; just type "make <board_name>_config".
269 Example: For a TQM823L module type:
274 For the Cogent platform, you need to specify the CPU type as well;
275 e.g. "make cogent_mpc8xx_config". And also configure the cogent
276 directory according to the instructions in cogent/README.
279 Configuration Options:
280 ----------------------
282 Configuration depends on the combination of board and CPU type; all
283 such information is kept in a configuration file
284 "include/configs/<board_name>.h".
286 Example: For a TQM823L module, all configuration settings are in
287 "include/configs/TQM823L.h".
290 Many of the options are named exactly as the corresponding Linux
291 kernel configuration options. The intention is to make it easier to
292 build a config tool - later.
295 The following options need to be configured:
297 - CPU Type: Define exactly one, e.g. CONFIG_MPC85XX.
299 - Board Type: Define exactly one, e.g. CONFIG_MPC8540ADS.
301 - CPU Daughterboard Type: (if CONFIG_ATSTK1000 is defined)
302 Define exactly one, e.g. CONFIG_ATSTK1002
304 - CPU Module Type: (if CONFIG_COGENT is defined)
305 Define exactly one of
307 --- FIXME --- not tested yet:
308 CONFIG_CMA286_60, CONFIG_CMA286_21, CONFIG_CMA286_60P,
309 CONFIG_CMA287_23, CONFIG_CMA287_50
311 - Motherboard Type: (if CONFIG_COGENT is defined)
312 Define exactly one of
313 CONFIG_CMA101, CONFIG_CMA102
315 - Motherboard I/O Modules: (if CONFIG_COGENT is defined)
316 Define one or more of
319 - Motherboard Options: (if CONFIG_CMA101 or CONFIG_CMA102 are defined)
320 Define one or more of
321 CONFIG_LCD_HEARTBEAT - update a character position on
322 the LCD display every second with
325 - Board flavour: (if CONFIG_MPC8260ADS is defined)
328 CONFIG_SYS_8260ADS - original MPC8260ADS
329 CONFIG_SYS_8266ADS - MPC8266ADS
330 CONFIG_SYS_PQ2FADS - PQ2FADS-ZU or PQ2FADS-VR
331 CONFIG_SYS_8272ADS - MPC8272ADS
333 - Marvell Family Member
334 CONFIG_SYS_MVFS - define it if you want to enable
335 multiple fs option at one time
336 for marvell soc family
338 - MPC824X Family Member (if CONFIG_MPC824X is defined)
339 Define exactly one of
340 CONFIG_MPC8240, CONFIG_MPC8245
342 - 8xx CPU Options: (if using an MPC8xx CPU)
343 CONFIG_8xx_GCLK_FREQ - deprecated: CPU clock if
344 get_gclk_freq() cannot work
345 e.g. if there is no 32KHz
346 reference PIT/RTC clock
347 CONFIG_8xx_OSCLK - PLL input clock (either EXTCLK
350 - 859/866/885 CPU options: (if using a MPC859 or MPC866 or MPC885 CPU):
351 CONFIG_SYS_8xx_CPUCLK_MIN
352 CONFIG_SYS_8xx_CPUCLK_MAX
353 CONFIG_8xx_CPUCLK_DEFAULT
354 See doc/README.MPC866
356 CONFIG_SYS_MEASURE_CPUCLK
358 Define this to measure the actual CPU clock instead
359 of relying on the correctness of the configured
360 values. Mostly useful for board bringup to make sure
361 the PLL is locked at the intended frequency. Note
362 that this requires a (stable) reference clock (32 kHz
363 RTC clock or CONFIG_SYS_8XX_XIN)
365 CONFIG_SYS_DELAYED_ICACHE
367 Define this option if you want to enable the
368 ICache only when Code runs from RAM.
373 Specifies that the core is a 64-bit PowerPC implementation (implements
374 the "64" category of the Power ISA). This is necessary for ePAPR
375 compliance, among other possible reasons.
377 CONFIG_SYS_FSL_TBCLK_DIV
379 Defines the core time base clock divider ratio compared to the
380 system clock. On most PQ3 devices this is 8, on newer QorIQ
381 devices it can be 16 or 32. The ratio varies from SoC to Soc.
383 CONFIG_SYS_FSL_PCIE_COMPAT
385 Defines the string to utilize when trying to match PCIe device
386 tree nodes for the given platform.
388 CONFIG_SYS_PPC_E500_DEBUG_TLB
390 Enables a temporary TLB entry to be used during boot to work
391 around limitations in e500v1 and e500v2 external debugger
392 support. This reduces the portions of the boot code where
393 breakpoints and single stepping do not work. The value of this
394 symbol should be set to the TLB1 entry to be used for this
397 CONFIG_SYS_FSL_ERRATUM_A004510
399 Enables a workaround for erratum A004510. If set,
400 then CONFIG_SYS_FSL_ERRATUM_A004510_SVR_REV and
401 CONFIG_SYS_FSL_CORENET_SNOOPVEC_COREONLY must be set.
403 CONFIG_SYS_FSL_ERRATUM_A004510_SVR_REV
404 CONFIG_SYS_FSL_ERRATUM_A004510_SVR_REV2 (optional)
406 Defines one or two SoC revisions (low 8 bits of SVR)
407 for which the A004510 workaround should be applied.
409 The rest of SVR is either not relevant to the decision
410 of whether the erratum is present (e.g. p2040 versus
411 p2041) or is implied by the build target, which controls
412 whether CONFIG_SYS_FSL_ERRATUM_A004510 is set.
414 See Freescale App Note 4493 for more information about
417 CONFIG_SYS_FSL_CORENET_SNOOPVEC_COREONLY
419 This is the value to write into CCSR offset 0x18600
420 according to the A004510 workaround.
422 - Generic CPU options:
423 CONFIG_SYS_BIG_ENDIAN, CONFIG_SYS_LITTLE_ENDIAN
425 Defines the endianess of the CPU. Implementation of those
426 values is arch specific.
428 - Intel Monahans options:
429 CONFIG_SYS_MONAHANS_RUN_MODE_OSC_RATIO
431 Defines the Monahans run mode to oscillator
432 ratio. Valid values are 8, 16, 24, 31. The core
433 frequency is this value multiplied by 13 MHz.
435 CONFIG_SYS_MONAHANS_TURBO_RUN_MODE_RATIO
437 Defines the Monahans turbo mode to oscillator
438 ratio. Valid values are 1 (default if undefined) and
439 2. The core frequency as calculated above is multiplied
443 CONFIG_SYS_INIT_SP_OFFSET
445 Offset relative to CONFIG_SYS_SDRAM_BASE for initial stack
446 pointer. This is needed for the temporary stack before
449 CONFIG_SYS_MIPS_CACHE_MODE
451 Cache operation mode for the MIPS CPU.
452 See also arch/mips/include/asm/mipsregs.h.
454 CONF_CM_CACHABLE_NO_WA
457 CONF_CM_CACHABLE_NONCOHERENT
461 CONF_CM_CACHABLE_ACCELERATED
463 CONFIG_SYS_XWAY_EBU_BOOTCFG
465 Special option for Lantiq XWAY SoCs for booting from NOR flash.
466 See also arch/mips/cpu/mips32/start.S.
468 CONFIG_XWAY_SWAP_BYTES
470 Enable compilation of tools/xway-swap-bytes needed for Lantiq
471 XWAY SoCs for booting from NOR flash. The U-Boot image needs to
472 be swapped if a flash programmer is used.
475 CONFIG_SYS_EXCEPTION_VECTORS_HIGH
477 Select high exception vectors of the ARM core, e.g., do not
478 clear the V bit of the c1 register of CP15.
480 CONFIG_SYS_THUMB_BUILD
482 Use this flag to build U-Boot using the Thumb instruction
483 set for ARM architectures. Thumb instruction set provides
484 better code density. For ARM architectures that support
485 Thumb2 this flag will result in Thumb2 code generated by
488 - Linux Kernel Interface:
491 U-Boot stores all clock information in Hz
492 internally. For binary compatibility with older Linux
493 kernels (which expect the clocks passed in the
494 bd_info data to be in MHz) the environment variable
495 "clocks_in_mhz" can be defined so that U-Boot
496 converts clock data to MHZ before passing it to the
498 When CONFIG_CLOCKS_IN_MHZ is defined, a definition of
499 "clocks_in_mhz=1" is automatically included in the
502 CONFIG_MEMSIZE_IN_BYTES [relevant for MIPS only]
504 When transferring memsize parameter to linux, some versions
505 expect it to be in bytes, others in MB.
506 Define CONFIG_MEMSIZE_IN_BYTES to make it in bytes.
510 New kernel versions are expecting firmware settings to be
511 passed using flattened device trees (based on open firmware
515 * New libfdt-based support
516 * Adds the "fdt" command
517 * The bootm command automatically updates the fdt
519 OF_CPU - The proper name of the cpus node (only required for
520 MPC512X and MPC5xxx based boards).
521 OF_SOC - The proper name of the soc node (only required for
522 MPC512X and MPC5xxx based boards).
523 OF_TBCLK - The timebase frequency.
524 OF_STDOUT_PATH - The path to the console device
526 boards with QUICC Engines require OF_QE to set UCC MAC
529 CONFIG_OF_BOARD_SETUP
531 Board code has addition modification that it wants to make
532 to the flat device tree before handing it off to the kernel
536 This define fills in the correct boot CPU in the boot
537 param header, the default value is zero if undefined.
541 U-Boot can detect if an IDE device is present or not.
542 If not, and this new config option is activated, U-Boot
543 removes the ATA node from the DTS before booting Linux,
544 so the Linux IDE driver does not probe the device and
545 crash. This is needed for buggy hardware (uc101) where
546 no pull down resistor is connected to the signal IDE5V_DD7.
548 CONFIG_MACH_TYPE [relevant for ARM only][mandatory]
550 This setting is mandatory for all boards that have only one
551 machine type and must be used to specify the machine type
552 number as it appears in the ARM machine registry
553 (see http://www.arm.linux.org.uk/developer/machines/).
554 Only boards that have multiple machine types supported
555 in a single configuration file and the machine type is
556 runtime discoverable, do not have to use this setting.
558 - vxWorks boot parameters:
560 bootvx constructs a valid bootline using the following
561 environments variables: bootfile, ipaddr, serverip, hostname.
562 It loads the vxWorks image pointed bootfile.
564 CONFIG_SYS_VXWORKS_BOOT_DEVICE - The vxworks device name
565 CONFIG_SYS_VXWORKS_MAC_PTR - Ethernet 6 byte MA -address
566 CONFIG_SYS_VXWORKS_SERVERNAME - Name of the server
567 CONFIG_SYS_VXWORKS_BOOT_ADDR - Address of boot parameters
569 CONFIG_SYS_VXWORKS_ADD_PARAMS
571 Add it at the end of the bootline. E.g "u=username pw=secret"
573 Note: If a "bootargs" environment is defined, it will overwride
574 the defaults discussed just above.
576 - Cache Configuration:
577 CONFIG_SYS_ICACHE_OFF - Do not enable instruction cache in U-Boot
578 CONFIG_SYS_DCACHE_OFF - Do not enable data cache in U-Boot
579 CONFIG_SYS_L2CACHE_OFF- Do not enable L2 cache in U-Boot
581 - Cache Configuration for ARM:
582 CONFIG_SYS_L2_PL310 - Enable support for ARM PL310 L2 cache
584 CONFIG_SYS_PL310_BASE - Physical base address of PL310
585 controller register space
590 Define this if you want support for Amba PrimeCell PL010 UARTs.
594 Define this if you want support for Amba PrimeCell PL011 UARTs.
598 If you have Amba PrimeCell PL011 UARTs, set this variable to
599 the clock speed of the UARTs.
603 If you have Amba PrimeCell PL010 or PL011 UARTs on your board,
604 define this to a list of base addresses for each (supported)
605 port. See e.g. include/configs/versatile.h
607 CONFIG_PL011_SERIAL_RLCR
609 Some vendor versions of PL011 serial ports (e.g. ST-Ericsson U8500)
610 have separate receive and transmit line control registers. Set
611 this variable to initialize the extra register.
613 CONFIG_PL011_SERIAL_FLUSH_ON_INIT
615 On some platforms (e.g. U8500) U-Boot is loaded by a second stage
616 boot loader that has already initialized the UART. Define this
617 variable to flush the UART at init time.
621 Depending on board, define exactly one serial port
622 (like CONFIG_8xx_CONS_SMC1, CONFIG_8xx_CONS_SMC2,
623 CONFIG_8xx_CONS_SCC1, ...), or switch off the serial
624 console by defining CONFIG_8xx_CONS_NONE
626 Note: if CONFIG_8xx_CONS_NONE is defined, the serial
627 port routines must be defined elsewhere
628 (i.e. serial_init(), serial_getc(), ...)
631 Enables console device for a color framebuffer. Needs following
632 defines (cf. smiLynxEM, i8042)
633 VIDEO_FB_LITTLE_ENDIAN graphic memory organisation
635 VIDEO_HW_RECTFILL graphic chip supports
638 VIDEO_HW_BITBLT graphic chip supports
639 bit-blit (cf. smiLynxEM)
640 VIDEO_VISIBLE_COLS visible pixel columns
642 VIDEO_VISIBLE_ROWS visible pixel rows
643 VIDEO_PIXEL_SIZE bytes per pixel
644 VIDEO_DATA_FORMAT graphic data format
645 (0-5, cf. cfb_console.c)
646 VIDEO_FB_ADRS framebuffer address
647 VIDEO_KBD_INIT_FCT keyboard int fct
648 (i.e. i8042_kbd_init())
649 VIDEO_TSTC_FCT test char fct
651 VIDEO_GETC_FCT get char fct
653 CONFIG_CONSOLE_CURSOR cursor drawing on/off
654 (requires blink timer
656 CONFIG_SYS_CONSOLE_BLINK_COUNT blink interval (cf. i8042.c)
657 CONFIG_CONSOLE_TIME display time/date info in
659 (requires CONFIG_CMD_DATE)
660 CONFIG_VIDEO_LOGO display Linux logo in
662 CONFIG_VIDEO_BMP_LOGO use bmp_logo.h instead of
663 linux_logo.h for logo.
664 Requires CONFIG_VIDEO_LOGO
665 CONFIG_CONSOLE_EXTRA_INFO
666 additional board info beside
669 When CONFIG_CFB_CONSOLE_ANSI is defined, console will support
670 a limited number of ANSI escape sequences (cursor control,
671 erase functions and limited graphics rendition control).
673 When CONFIG_CFB_CONSOLE is defined, video console is
674 default i/o. Serial console can be forced with
675 environment 'console=serial'.
677 When CONFIG_SILENT_CONSOLE is defined, all console
678 messages (by U-Boot and Linux!) can be silenced with
679 the "silent" environment variable. See
680 doc/README.silent for more information.
683 CONFIG_BAUDRATE - in bps
684 Select one of the baudrates listed in
685 CONFIG_SYS_BAUDRATE_TABLE, see below.
686 CONFIG_SYS_BRGCLK_PRESCALE, baudrate prescale
688 - Console Rx buffer length
689 With CONFIG_SYS_SMC_RXBUFLEN it is possible to define
690 the maximum receive buffer length for the SMC.
691 This option is actual only for 82xx and 8xx possible.
692 If using CONFIG_SYS_SMC_RXBUFLEN also CONFIG_SYS_MAXIDLE
693 must be defined, to setup the maximum idle timeout for
696 - Pre-Console Buffer:
697 Prior to the console being initialised (i.e. serial UART
698 initialised etc) all console output is silently discarded.
699 Defining CONFIG_PRE_CONSOLE_BUFFER will cause U-Boot to
700 buffer any console messages prior to the console being
701 initialised to a buffer of size CONFIG_PRE_CON_BUF_SZ
702 bytes located at CONFIG_PRE_CON_BUF_ADDR. The buffer is
703 a circular buffer, so if more than CONFIG_PRE_CON_BUF_SZ
704 bytes are output before the console is initialised, the
705 earlier bytes are discarded.
707 'Sane' compilers will generate smaller code if
708 CONFIG_PRE_CON_BUF_SZ is a power of 2
710 - Safe printf() functions
711 Define CONFIG_SYS_VSNPRINTF to compile in safe versions of
712 the printf() functions. These are defined in
713 include/vsprintf.h and include snprintf(), vsnprintf() and
714 so on. Code size increase is approximately 300-500 bytes.
715 If this option is not given then these functions will
716 silently discard their buffer size argument - this means
717 you are not getting any overflow checking in this case.
719 - Boot Delay: CONFIG_BOOTDELAY - in seconds
720 Delay before automatically booting the default image;
721 set to -1 to disable autoboot.
722 set to -2 to autoboot with no delay and not check for abort
723 (even when CONFIG_ZERO_BOOTDELAY_CHECK is defined).
725 See doc/README.autoboot for these options that
726 work with CONFIG_BOOTDELAY. None are required.
727 CONFIG_BOOT_RETRY_TIME
728 CONFIG_BOOT_RETRY_MIN
729 CONFIG_AUTOBOOT_KEYED
730 CONFIG_AUTOBOOT_PROMPT
731 CONFIG_AUTOBOOT_DELAY_STR
732 CONFIG_AUTOBOOT_STOP_STR
733 CONFIG_AUTOBOOT_DELAY_STR2
734 CONFIG_AUTOBOOT_STOP_STR2
735 CONFIG_ZERO_BOOTDELAY_CHECK
736 CONFIG_RESET_TO_RETRY
740 Only needed when CONFIG_BOOTDELAY is enabled;
741 define a command string that is automatically executed
742 when no character is read on the console interface
743 within "Boot Delay" after reset.
746 This can be used to pass arguments to the bootm
747 command. The value of CONFIG_BOOTARGS goes into the
748 environment value "bootargs".
750 CONFIG_RAMBOOT and CONFIG_NFSBOOT
751 The value of these goes into the environment as
752 "ramboot" and "nfsboot" respectively, and can be used
753 as a convenience, when switching between booting from
759 When this option is #defined, the existence of the
760 environment variable "preboot" will be checked
761 immediately before starting the CONFIG_BOOTDELAY
762 countdown and/or running the auto-boot command resp.
763 entering interactive mode.
765 This feature is especially useful when "preboot" is
766 automatically generated or modified. For an example
767 see the LWMON board specific code: here "preboot" is
768 modified when the user holds down a certain
769 combination of keys on the (special) keyboard when
772 - Serial Download Echo Mode:
774 If defined to 1, all characters received during a
775 serial download (using the "loads" command) are
776 echoed back. This might be needed by some terminal
777 emulations (like "cu"), but may as well just take
778 time on others. This setting #define's the initial
779 value of the "loads_echo" environment variable.
781 - Kgdb Serial Baudrate: (if CONFIG_CMD_KGDB is defined)
783 Select one of the baudrates listed in
784 CONFIG_SYS_BAUDRATE_TABLE, see below.
787 Monitor commands can be included or excluded
788 from the build by using the #include files
789 <config_cmd_all.h> and #undef'ing unwanted
790 commands, or using <config_cmd_default.h>
791 and augmenting with additional #define's
794 The default command configuration includes all commands
795 except those marked below with a "*".
797 CONFIG_CMD_ASKENV * ask for env variable
798 CONFIG_CMD_BDI bdinfo
799 CONFIG_CMD_BEDBUG * Include BedBug Debugger
800 CONFIG_CMD_BMP * BMP support
801 CONFIG_CMD_BSP * Board specific commands
802 CONFIG_CMD_BOOTD bootd
803 CONFIG_CMD_CACHE * icache, dcache
804 CONFIG_CMD_CONSOLE coninfo
805 CONFIG_CMD_CRC32 * crc32
806 CONFIG_CMD_DATE * support for RTC, date/time...
807 CONFIG_CMD_DHCP * DHCP support
808 CONFIG_CMD_DIAG * Diagnostics
809 CONFIG_CMD_DS4510 * ds4510 I2C gpio commands
810 CONFIG_CMD_DS4510_INFO * ds4510 I2C info command
811 CONFIG_CMD_DS4510_MEM * ds4510 I2C eeprom/sram commansd
812 CONFIG_CMD_DS4510_RST * ds4510 I2C rst command
813 CONFIG_CMD_DTT * Digital Therm and Thermostat
814 CONFIG_CMD_ECHO echo arguments
815 CONFIG_CMD_EDITENV edit env variable
816 CONFIG_CMD_EEPROM * EEPROM read/write support
817 CONFIG_CMD_ELF * bootelf, bootvx
818 CONFIG_CMD_EXPORTENV * export the environment
819 CONFIG_CMD_EXT2 * ext2 command support
820 CONFIG_CMD_EXT4 * ext4 command support
821 CONFIG_CMD_SAVEENV saveenv
822 CONFIG_CMD_FDC * Floppy Disk Support
823 CONFIG_CMD_FAT * FAT command support
824 CONFIG_CMD_FDOS * Dos diskette Support
825 CONFIG_CMD_FLASH flinfo, erase, protect
826 CONFIG_CMD_FPGA FPGA device initialization support
827 CONFIG_CMD_GETTIME * Get time since boot
828 CONFIG_CMD_GO * the 'go' command (exec code)
829 CONFIG_CMD_GREPENV * search environment
830 CONFIG_CMD_HASH * calculate hash / digest
831 CONFIG_CMD_HWFLOW * RTS/CTS hw flow control
832 CONFIG_CMD_I2C * I2C serial bus support
833 CONFIG_CMD_IDE * IDE harddisk support
834 CONFIG_CMD_IMI iminfo
835 CONFIG_CMD_IMLS List all found images
836 CONFIG_CMD_IMMAP * IMMR dump support
837 CONFIG_CMD_IMPORTENV * import an environment
838 CONFIG_CMD_INI * import data from an ini file into the env
839 CONFIG_CMD_IRQ * irqinfo
840 CONFIG_CMD_ITEST Integer/string test of 2 values
841 CONFIG_CMD_JFFS2 * JFFS2 Support
842 CONFIG_CMD_KGDB * kgdb
843 CONFIG_CMD_LDRINFO ldrinfo (display Blackfin loader)
844 CONFIG_CMD_LINK_LOCAL * link-local IP address auto-configuration
846 CONFIG_CMD_LOADB loadb
847 CONFIG_CMD_LOADS loads
848 CONFIG_CMD_MD5SUM print md5 message digest
849 (requires CONFIG_CMD_MEMORY and CONFIG_MD5)
850 CONFIG_CMD_MEMORY md, mm, nm, mw, cp, cmp, crc, base,
852 CONFIG_CMD_MISC Misc functions like sleep etc
853 CONFIG_CMD_MMC * MMC memory mapped support
854 CONFIG_CMD_MII * MII utility commands
855 CONFIG_CMD_MTDPARTS * MTD partition support
856 CONFIG_CMD_NAND * NAND support
857 CONFIG_CMD_NET bootp, tftpboot, rarpboot
858 CONFIG_CMD_PCA953X * PCA953x I2C gpio commands
859 CONFIG_CMD_PCA953X_INFO * PCA953x I2C gpio info command
860 CONFIG_CMD_PCI * pciinfo
861 CONFIG_CMD_PCMCIA * PCMCIA support
862 CONFIG_CMD_PING * send ICMP ECHO_REQUEST to network
864 CONFIG_CMD_PORTIO * Port I/O
865 CONFIG_CMD_READ * Read raw data from partition
866 CONFIG_CMD_REGINFO * Register dump
867 CONFIG_CMD_RUN run command in env variable
868 CONFIG_CMD_SAVES * save S record dump
869 CONFIG_CMD_SCSI * SCSI Support
870 CONFIG_CMD_SDRAM * print SDRAM configuration information
871 (requires CONFIG_CMD_I2C)
872 CONFIG_CMD_SETGETDCR Support for DCR Register access
874 CONFIG_CMD_SF * Read/write/erase SPI NOR flash
875 CONFIG_CMD_SHA1SUM print sha1 memory digest
876 (requires CONFIG_CMD_MEMORY)
877 CONFIG_CMD_SOURCE "source" command Support
878 CONFIG_CMD_SPI * SPI serial bus support
879 CONFIG_CMD_TFTPSRV * TFTP transfer in server mode
880 CONFIG_CMD_TFTPPUT * TFTP put command (upload)
881 CONFIG_CMD_TIME * run command and report execution time (ARM specific)
882 CONFIG_CMD_TIMER * access to the system tick timer
883 CONFIG_CMD_USB * USB support
884 CONFIG_CMD_CDP * Cisco Discover Protocol support
885 CONFIG_CMD_MFSL * Microblaze FSL support
888 EXAMPLE: If you want all functions except of network
889 support you can write:
891 #include "config_cmd_all.h"
892 #undef CONFIG_CMD_NET
895 fdt (flattened device tree) command: CONFIG_OF_LIBFDT
897 Note: Don't enable the "icache" and "dcache" commands
898 (configuration option CONFIG_CMD_CACHE) unless you know
899 what you (and your U-Boot users) are doing. Data
900 cache cannot be enabled on systems like the 8xx or
901 8260 (where accesses to the IMMR region must be
902 uncached), and it cannot be disabled on all other
903 systems where we (mis-) use the data cache to hold an
904 initial stack and some data.
907 XXX - this list needs to get updated!
911 If this variable is defined, U-Boot will use a device tree
912 to configure its devices, instead of relying on statically
913 compiled #defines in the board file. This option is
914 experimental and only available on a few boards. The device
915 tree is available in the global data as gd->fdt_blob.
917 U-Boot needs to get its device tree from somewhere. This can
918 be done using one of the two options below:
921 If this variable is defined, U-Boot will embed a device tree
922 binary in its image. This device tree file should be in the
923 board directory and called <soc>-<board>.dts. The binary file
924 is then picked up in board_init_f() and made available through
925 the global data structure as gd->blob.
928 If this variable is defined, U-Boot will build a device tree
929 binary. It will be called u-boot.dtb. Architecture-specific
930 code will locate it at run-time. Generally this works by:
932 cat u-boot.bin u-boot.dtb >image.bin
934 and in fact, U-Boot does this for you, creating a file called
935 u-boot-dtb.bin which is useful in the common case. You can
936 still use the individual files if you need something more
941 If this variable is defined, it enables watchdog
942 support for the SoC. There must be support in the SoC
943 specific code for a watchdog. For the 8xx and 8260
944 CPUs, the SIU Watchdog feature is enabled in the SYPCR
945 register. When supported for a specific SoC is
946 available, then no further board specific code should
950 When using a watchdog circuitry external to the used
951 SoC, then define this variable and provide board
952 specific code for the "hw_watchdog_reset" function.
955 CONFIG_VERSION_VARIABLE
956 If this variable is defined, an environment variable
957 named "ver" is created by U-Boot showing the U-Boot
958 version as printed by the "version" command.
959 Any change to this variable will be reverted at the
964 When CONFIG_CMD_DATE is selected, the type of the RTC
965 has to be selected, too. Define exactly one of the
968 CONFIG_RTC_MPC8xx - use internal RTC of MPC8xx
969 CONFIG_RTC_PCF8563 - use Philips PCF8563 RTC
970 CONFIG_RTC_MC13XXX - use MC13783 or MC13892 RTC
971 CONFIG_RTC_MC146818 - use MC146818 RTC
972 CONFIG_RTC_DS1307 - use Maxim, Inc. DS1307 RTC
973 CONFIG_RTC_DS1337 - use Maxim, Inc. DS1337 RTC
974 CONFIG_RTC_DS1338 - use Maxim, Inc. DS1338 RTC
975 CONFIG_RTC_DS164x - use Dallas DS164x RTC
976 CONFIG_RTC_ISL1208 - use Intersil ISL1208 RTC
977 CONFIG_RTC_MAX6900 - use Maxim, Inc. MAX6900 RTC
978 CONFIG_SYS_RTC_DS1337_NOOSC - Turn off the OSC output for DS1337
979 CONFIG_SYS_RV3029_TCR - enable trickle charger on
982 Note that if the RTC uses I2C, then the I2C interface
983 must also be configured. See I2C Support, below.
986 CONFIG_PCA953X - use NXP's PCA953X series I2C GPIO
987 CONFIG_PCA953X_INFO - enable pca953x info command
989 The CONFIG_SYS_I2C_PCA953X_WIDTH option specifies a list of
990 chip-ngpio pairs that tell the PCA953X driver the number of
991 pins supported by a particular chip.
993 Note that if the GPIO device uses I2C, then the I2C interface
994 must also be configured. See I2C Support, below.
998 When CONFIG_TIMESTAMP is selected, the timestamp
999 (date and time) of an image is printed by image
1000 commands like bootm or iminfo. This option is
1001 automatically enabled when you select CONFIG_CMD_DATE .
1003 - Partition Labels (disklabels) Supported:
1004 Zero or more of the following:
1005 CONFIG_MAC_PARTITION Apple's MacOS partition table.
1006 CONFIG_DOS_PARTITION MS Dos partition table, traditional on the
1007 Intel architecture, USB sticks, etc.
1008 CONFIG_ISO_PARTITION ISO partition table, used on CDROM etc.
1009 CONFIG_EFI_PARTITION GPT partition table, common when EFI is the
1010 bootloader. Note 2TB partition limit; see
1012 CONFIG_MTD_PARTITIONS Memory Technology Device partition table.
1014 If IDE or SCSI support is enabled (CONFIG_CMD_IDE or
1015 CONFIG_CMD_SCSI) you must configure support for at
1016 least one non-MTD partition type as well.
1019 CONFIG_IDE_RESET_ROUTINE - this is defined in several
1020 board configurations files but used nowhere!
1022 CONFIG_IDE_RESET - is this is defined, IDE Reset will
1023 be performed by calling the function
1024 ide_set_reset(int reset)
1025 which has to be defined in a board specific file
1030 Set this to enable ATAPI support.
1035 Set this to enable support for disks larger than 137GB
1036 Also look at CONFIG_SYS_64BIT_LBA.
1037 Whithout these , LBA48 support uses 32bit variables and will 'only'
1038 support disks up to 2.1TB.
1040 CONFIG_SYS_64BIT_LBA:
1041 When enabled, makes the IDE subsystem use 64bit sector addresses.
1045 At the moment only there is only support for the
1046 SYM53C8XX SCSI controller; define
1047 CONFIG_SCSI_SYM53C8XX to enable it.
1049 CONFIG_SYS_SCSI_MAX_LUN [8], CONFIG_SYS_SCSI_MAX_SCSI_ID [7] and
1050 CONFIG_SYS_SCSI_MAX_DEVICE [CONFIG_SYS_SCSI_MAX_SCSI_ID *
1051 CONFIG_SYS_SCSI_MAX_LUN] can be adjusted to define the
1052 maximum numbers of LUNs, SCSI ID's and target
1054 CONFIG_SYS_SCSI_SYM53C8XX_CCF to fix clock timing (80Mhz)
1056 The environment variable 'scsidevs' is set to the number of
1057 SCSI devices found during the last scan.
1059 - NETWORK Support (PCI):
1061 Support for Intel 8254x/8257x gigabit chips.
1064 Utility code for direct access to the SPI bus on Intel 8257x.
1065 This does not do anything useful unless you set at least one
1066 of CONFIG_CMD_E1000 or CONFIG_E1000_SPI_GENERIC.
1068 CONFIG_E1000_SPI_GENERIC
1069 Allow generic access to the SPI bus on the Intel 8257x, for
1070 example with the "sspi" command.
1073 Management command for E1000 devices. When used on devices
1074 with SPI support you can reprogram the EEPROM from U-Boot.
1076 CONFIG_E1000_FALLBACK_MAC
1077 default MAC for empty EEPROM after production.
1080 Support for Intel 82557/82559/82559ER chips.
1081 Optional CONFIG_EEPRO100_SROM_WRITE enables EEPROM
1082 write routine for first time initialisation.
1085 Support for Digital 2114x chips.
1086 Optional CONFIG_TULIP_SELECT_MEDIA for board specific
1087 modem chip initialisation (KS8761/QS6611).
1090 Support for National dp83815 chips.
1093 Support for National dp8382[01] gigabit chips.
1095 - NETWORK Support (other):
1097 CONFIG_DRIVER_AT91EMAC
1098 Support for AT91RM9200 EMAC.
1101 Define this to use reduced MII inteface
1103 CONFIG_DRIVER_AT91EMAC_QUIET
1104 If this defined, the driver is quiet.
1105 The driver doen't show link status messages.
1107 CONFIG_CALXEDA_XGMAC
1108 Support for the Calxeda XGMAC device
1111 Support for SMSC's LAN91C96 chips.
1113 CONFIG_LAN91C96_BASE
1114 Define this to hold the physical address
1115 of the LAN91C96's I/O space
1117 CONFIG_LAN91C96_USE_32_BIT
1118 Define this to enable 32 bit addressing
1121 Support for SMSC's LAN91C111 chip
1123 CONFIG_SMC91111_BASE
1124 Define this to hold the physical address
1125 of the device (I/O space)
1127 CONFIG_SMC_USE_32_BIT
1128 Define this if data bus is 32 bits
1130 CONFIG_SMC_USE_IOFUNCS
1131 Define this to use i/o functions instead of macros
1132 (some hardware wont work with macros)
1134 CONFIG_DRIVER_TI_EMAC
1135 Support for davinci emac
1137 CONFIG_SYS_DAVINCI_EMAC_PHY_COUNT
1138 Define this if you have more then 3 PHYs.
1141 Support for Faraday's FTGMAC100 Gigabit SoC Ethernet
1143 CONFIG_FTGMAC100_EGIGA
1144 Define this to use GE link update with gigabit PHY.
1145 Define this if FTGMAC100 is connected to gigabit PHY.
1146 If your system has 10/100 PHY only, it might not occur
1147 wrong behavior. Because PHY usually return timeout or
1148 useless data when polling gigabit status and gigabit
1149 control registers. This behavior won't affect the
1150 correctnessof 10/100 link speed update.
1153 Support for SMSC's LAN911x and LAN921x chips
1156 Define this to hold the physical address
1157 of the device (I/O space)
1159 CONFIG_SMC911X_32_BIT
1160 Define this if data bus is 32 bits
1162 CONFIG_SMC911X_16_BIT
1163 Define this if data bus is 16 bits. If your processor
1164 automatically converts one 32 bit word to two 16 bit
1165 words you may also try CONFIG_SMC911X_32_BIT.
1168 Support for Renesas on-chip Ethernet controller
1170 CONFIG_SH_ETHER_USE_PORT
1171 Define the number of ports to be used
1173 CONFIG_SH_ETHER_PHY_ADDR
1174 Define the ETH PHY's address
1176 CONFIG_SH_ETHER_CACHE_WRITEBACK
1177 If this option is set, the driver enables cache flush.
1180 CONFIG_GENERIC_LPC_TPM
1181 Support for generic parallel port TPM devices. Only one device
1182 per system is supported at this time.
1184 CONFIG_TPM_TIS_BASE_ADDRESS
1185 Base address where the generic TPM device is mapped
1186 to. Contemporary x86 systems usually map it at
1190 At the moment only the UHCI host controller is
1191 supported (PIP405, MIP405, MPC5200); define
1192 CONFIG_USB_UHCI to enable it.
1193 define CONFIG_USB_KEYBOARD to enable the USB Keyboard
1194 and define CONFIG_USB_STORAGE to enable the USB
1197 Supported are USB Keyboards and USB Floppy drives
1199 MPC5200 USB requires additional defines:
1201 for 528 MHz Clock: 0x0001bbbb
1205 for differential drivers: 0x00001000
1206 for single ended drivers: 0x00005000
1207 for differential drivers on PSC3: 0x00000100
1208 for single ended drivers on PSC3: 0x00004100
1209 CONFIG_SYS_USB_EVENT_POLL
1210 May be defined to allow interrupt polling
1211 instead of using asynchronous interrupts
1213 CONFIG_USB_EHCI_TXFIFO_THRESH enables setting of the
1214 txfilltuning field in the EHCI controller on reset.
1217 Define the below if you wish to use the USB console.
1218 Once firmware is rebuilt from a serial console issue the
1219 command "setenv stdin usbtty; setenv stdout usbtty" and
1220 attach your USB cable. The Unix command "dmesg" should print
1221 it has found a new device. The environment variable usbtty
1222 can be set to gserial or cdc_acm to enable your device to
1223 appear to a USB host as a Linux gserial device or a
1224 Common Device Class Abstract Control Model serial device.
1225 If you select usbtty = gserial you should be able to enumerate
1227 # modprobe usbserial vendor=0xVendorID product=0xProductID
1228 else if using cdc_acm, simply setting the environment
1229 variable usbtty to be cdc_acm should suffice. The following
1230 might be defined in YourBoardName.h
1233 Define this to build a UDC device
1236 Define this to have a tty type of device available to
1237 talk to the UDC device
1240 Define this to enable the high speed support for usb
1241 device and usbtty. If this feature is enabled, a routine
1242 int is_usbd_high_speed(void)
1243 also needs to be defined by the driver to dynamically poll
1244 whether the enumeration has succeded at high speed or full
1247 CONFIG_SYS_CONSOLE_IS_IN_ENV
1248 Define this if you want stdin, stdout &/or stderr to
1252 CONFIG_SYS_USB_EXTC_CLK 0xBLAH
1253 Derive USB clock from external clock "blah"
1254 - CONFIG_SYS_USB_EXTC_CLK 0x02
1256 CONFIG_SYS_USB_BRG_CLK 0xBLAH
1257 Derive USB clock from brgclk
1258 - CONFIG_SYS_USB_BRG_CLK 0x04
1260 If you have a USB-IF assigned VendorID then you may wish to
1261 define your own vendor specific values either in BoardName.h
1262 or directly in usbd_vendor_info.h. If you don't define
1263 CONFIG_USBD_MANUFACTURER, CONFIG_USBD_PRODUCT_NAME,
1264 CONFIG_USBD_VENDORID and CONFIG_USBD_PRODUCTID, then U-Boot
1265 should pretend to be a Linux device to it's target host.
1267 CONFIG_USBD_MANUFACTURER
1268 Define this string as the name of your company for
1269 - CONFIG_USBD_MANUFACTURER "my company"
1271 CONFIG_USBD_PRODUCT_NAME
1272 Define this string as the name of your product
1273 - CONFIG_USBD_PRODUCT_NAME "acme usb device"
1275 CONFIG_USBD_VENDORID
1276 Define this as your assigned Vendor ID from the USB
1277 Implementors Forum. This *must* be a genuine Vendor ID
1278 to avoid polluting the USB namespace.
1279 - CONFIG_USBD_VENDORID 0xFFFF
1281 CONFIG_USBD_PRODUCTID
1282 Define this as the unique Product ID
1284 - CONFIG_USBD_PRODUCTID 0xFFFF
1286 - ULPI Layer Support:
1287 The ULPI (UTMI Low Pin (count) Interface) PHYs are supported via
1288 the generic ULPI layer. The generic layer accesses the ULPI PHY
1289 via the platform viewport, so you need both the genric layer and
1290 the viewport enabled. Currently only Chipidea/ARC based
1291 viewport is supported.
1292 To enable the ULPI layer support, define CONFIG_USB_ULPI and
1293 CONFIG_USB_ULPI_VIEWPORT in your board configuration file.
1294 If your ULPI phy needs a different reference clock than the
1295 standard 24 MHz then you have to define CONFIG_ULPI_REF_CLK to
1296 the appropriate value in Hz.
1299 The MMC controller on the Intel PXA is supported. To
1300 enable this define CONFIG_MMC. The MMC can be
1301 accessed from the boot prompt by mapping the device
1302 to physical memory similar to flash. Command line is
1303 enabled with CONFIG_CMD_MMC. The MMC driver also works with
1304 the FAT fs. This is enabled with CONFIG_CMD_FAT.
1307 Support for Renesas on-chip MMCIF controller
1309 CONFIG_SH_MMCIF_ADDR
1310 Define the base address of MMCIF registers
1313 Define the clock frequency for MMCIF
1315 - Journaling Flash filesystem support:
1316 CONFIG_JFFS2_NAND, CONFIG_JFFS2_NAND_OFF, CONFIG_JFFS2_NAND_SIZE,
1317 CONFIG_JFFS2_NAND_DEV
1318 Define these for a default partition on a NAND device
1320 CONFIG_SYS_JFFS2_FIRST_SECTOR,
1321 CONFIG_SYS_JFFS2_FIRST_BANK, CONFIG_SYS_JFFS2_NUM_BANKS
1322 Define these for a default partition on a NOR device
1324 CONFIG_SYS_JFFS_CUSTOM_PART
1325 Define this to create an own partition. You have to provide a
1326 function struct part_info* jffs2_part_info(int part_num)
1328 If you define only one JFFS2 partition you may also want to
1329 #define CONFIG_SYS_JFFS_SINGLE_PART 1
1330 to disable the command chpart. This is the default when you
1331 have not defined a custom partition
1333 - FAT(File Allocation Table) filesystem write function support:
1336 Define this to enable support for saving memory data as a
1337 file in FAT formatted partition.
1339 This will also enable the command "fatwrite" enabling the
1340 user to write files to FAT.
1342 CBFS (Coreboot Filesystem) support
1345 Define this to enable support for reading from a Coreboot
1346 filesystem. Available commands are cbfsinit, cbfsinfo, cbfsls
1352 Define this to enable standard (PC-Style) keyboard
1356 Standard PC keyboard driver with US (is default) and
1357 GERMAN key layout (switch via environment 'keymap=de') support.
1358 Export function i8042_kbd_init, i8042_tstc and i8042_getc
1359 for cfb_console. Supports cursor blinking.
1364 Define this to enable video support (for output to
1367 CONFIG_VIDEO_CT69000
1369 Enable Chips & Technologies 69000 Video chip
1371 CONFIG_VIDEO_SMI_LYNXEM
1372 Enable Silicon Motion SMI 712/710/810 Video chip. The
1373 video output is selected via environment 'videoout'
1374 (1 = LCD and 2 = CRT). If videoout is undefined, CRT is
1377 For the CT69000 and SMI_LYNXEM drivers, videomode is
1378 selected via environment 'videomode'. Two different ways
1380 - "videomode=num" 'num' is a standard LiLo mode numbers.
1381 Following standard modes are supported (* is default):
1383 Colors 640x480 800x600 1024x768 1152x864 1280x1024
1384 -------------+---------------------------------------------
1385 8 bits | 0x301* 0x303 0x305 0x161 0x307
1386 15 bits | 0x310 0x313 0x316 0x162 0x319
1387 16 bits | 0x311 0x314 0x317 0x163 0x31A
1388 24 bits | 0x312 0x315 0x318 ? 0x31B
1389 -------------+---------------------------------------------
1390 (i.e. setenv videomode 317; saveenv; reset;)
1392 - "videomode=bootargs" all the video parameters are parsed
1393 from the bootargs. (See drivers/video/videomodes.c)
1396 CONFIG_VIDEO_SED13806
1397 Enable Epson SED13806 driver. This driver supports 8bpp
1398 and 16bpp modes defined by CONFIG_VIDEO_SED13806_8BPP
1399 or CONFIG_VIDEO_SED13806_16BPP
1402 Enable the Freescale DIU video driver. Reference boards for
1403 SOCs that have a DIU should define this macro to enable DIU
1404 support, and should also define these other macros:
1410 CONFIG_VIDEO_SW_CURSOR
1411 CONFIG_VGA_AS_SINGLE_DEVICE
1413 CONFIG_VIDEO_BMP_LOGO
1415 The DIU driver will look for the 'video-mode' environment
1416 variable, and if defined, enable the DIU as a console during
1417 boot. See the documentation file README.video for a
1418 description of this variable.
1422 Enable the VGA video / BIOS for x86. The alternative if you
1423 are using coreboot is to use the coreboot frame buffer
1430 Define this to enable a custom keyboard support.
1431 This simply calls drv_keyboard_init() which must be
1432 defined in your board-specific files.
1433 The only board using this so far is RBC823.
1435 - LCD Support: CONFIG_LCD
1437 Define this to enable LCD support (for output to LCD
1438 display); also select one of the supported displays
1439 by defining one of these:
1443 HITACHI TX09D70VM1CCA, 3.5", 240x320.
1445 CONFIG_NEC_NL6448AC33:
1447 NEC NL6448AC33-18. Active, color, single scan.
1449 CONFIG_NEC_NL6448BC20
1451 NEC NL6448BC20-08. 6.5", 640x480.
1452 Active, color, single scan.
1454 CONFIG_NEC_NL6448BC33_54
1456 NEC NL6448BC33-54. 10.4", 640x480.
1457 Active, color, single scan.
1461 Sharp 320x240. Active, color, single scan.
1462 It isn't 16x9, and I am not sure what it is.
1464 CONFIG_SHARP_LQ64D341
1466 Sharp LQ64D341 display, 640x480.
1467 Active, color, single scan.
1471 HLD1045 display, 640x480.
1472 Active, color, single scan.
1476 Optrex CBL50840-2 NF-FW 99 22 M5
1478 Hitachi LMG6912RPFC-00T
1482 320x240. Black & white.
1484 Normally display is black on white background; define
1485 CONFIG_SYS_WHITE_ON_BLACK to get it inverted.
1489 Support drawing of RLE8-compressed bitmaps on the LCD.
1493 Enables an 'i2c edid' command which can read EDID
1494 information over I2C from an attached LCD display.
1497 - Splash Screen Support: CONFIG_SPLASH_SCREEN
1499 If this option is set, the environment is checked for
1500 a variable "splashimage". If found, the usual display
1501 of logo, copyright and system information on the LCD
1502 is suppressed and the BMP image at the address
1503 specified in "splashimage" is loaded instead. The
1504 console is redirected to the "nulldev", too. This
1505 allows for a "silent" boot where a splash screen is
1506 loaded very quickly after power-on.
1508 CONFIG_SPLASH_SCREEN_ALIGN
1510 If this option is set the splash image can be freely positioned
1511 on the screen. Environment variable "splashpos" specifies the
1512 position as "x,y". If a positive number is given it is used as
1513 number of pixel from left/top. If a negative number is given it
1514 is used as number of pixel from right/bottom. You can also
1515 specify 'm' for centering the image.
1518 setenv splashpos m,m
1519 => image at center of screen
1521 setenv splashpos 30,20
1522 => image at x = 30 and y = 20
1524 setenv splashpos -10,m
1525 => vertically centered image
1526 at x = dspWidth - bmpWidth - 9
1528 - Gzip compressed BMP image support: CONFIG_VIDEO_BMP_GZIP
1530 If this option is set, additionally to standard BMP
1531 images, gzipped BMP images can be displayed via the
1532 splashscreen support or the bmp command.
1534 - Run length encoded BMP image (RLE8) support: CONFIG_VIDEO_BMP_RLE8
1536 If this option is set, 8-bit RLE compressed BMP images
1537 can be displayed via the splashscreen support or the
1540 - Do compresssing for memory range:
1543 If this option is set, it would use zlib deflate method
1544 to compress the specified memory at its best effort.
1546 - Compression support:
1549 If this option is set, support for bzip2 compressed
1550 images is included. If not, only uncompressed and gzip
1551 compressed images are supported.
1553 NOTE: the bzip2 algorithm requires a lot of RAM, so
1554 the malloc area (as defined by CONFIG_SYS_MALLOC_LEN) should
1559 If this option is set, support for lzma compressed
1562 Note: The LZMA algorithm adds between 2 and 4KB of code and it
1563 requires an amount of dynamic memory that is given by the
1566 (1846 + 768 << (lc + lp)) * sizeof(uint16)
1568 Where lc and lp stand for, respectively, Literal context bits
1569 and Literal pos bits.
1571 This value is upper-bounded by 14MB in the worst case. Anyway,
1572 for a ~4MB large kernel image, we have lc=3 and lp=0 for a
1573 total amount of (1846 + 768 << (3 + 0)) * 2 = ~41KB... that is
1574 a very small buffer.
1576 Use the lzmainfo tool to determinate the lc and lp values and
1577 then calculate the amount of needed dynamic memory (ensuring
1578 the appropriate CONFIG_SYS_MALLOC_LEN value).
1583 The address of PHY on MII bus.
1585 CONFIG_PHY_CLOCK_FREQ (ppc4xx)
1587 The clock frequency of the MII bus
1591 If this option is set, support for speed/duplex
1592 detection of gigabit PHY is included.
1594 CONFIG_PHY_RESET_DELAY
1596 Some PHY like Intel LXT971A need extra delay after
1597 reset before any MII register access is possible.
1598 For such PHY, set this option to the usec delay
1599 required. (minimum 300usec for LXT971A)
1601 CONFIG_PHY_CMD_DELAY (ppc4xx)
1603 Some PHY like Intel LXT971A need extra delay after
1604 command issued before MII status register can be read
1614 Define a default value for Ethernet address to use
1615 for the respective Ethernet interface, in case this
1616 is not determined automatically.
1621 Define a default value for the IP address to use for
1622 the default Ethernet interface, in case this is not
1623 determined through e.g. bootp.
1624 (Environment variable "ipaddr")
1626 - Server IP address:
1629 Defines a default value for the IP address of a TFTP
1630 server to contact when using the "tftboot" command.
1631 (Environment variable "serverip")
1633 CONFIG_KEEP_SERVERADDR
1635 Keeps the server's MAC address, in the env 'serveraddr'
1636 for passing to bootargs (like Linux's netconsole option)
1638 - Gateway IP address:
1641 Defines a default value for the IP address of the
1642 default router where packets to other networks are
1644 (Environment variable "gatewayip")
1649 Defines a default value for the subnet mask (or
1650 routing prefix) which is used to determine if an IP
1651 address belongs to the local subnet or needs to be
1652 forwarded through a router.
1653 (Environment variable "netmask")
1655 - Multicast TFTP Mode:
1658 Defines whether you want to support multicast TFTP as per
1659 rfc-2090; for example to work with atftp. Lets lots of targets
1660 tftp down the same boot image concurrently. Note: the Ethernet
1661 driver in use must provide a function: mcast() to join/leave a
1664 - BOOTP Recovery Mode:
1665 CONFIG_BOOTP_RANDOM_DELAY
1667 If you have many targets in a network that try to
1668 boot using BOOTP, you may want to avoid that all
1669 systems send out BOOTP requests at precisely the same
1670 moment (which would happen for instance at recovery
1671 from a power failure, when all systems will try to
1672 boot, thus flooding the BOOTP server. Defining
1673 CONFIG_BOOTP_RANDOM_DELAY causes a random delay to be
1674 inserted before sending out BOOTP requests. The
1675 following delays are inserted then:
1677 1st BOOTP request: delay 0 ... 1 sec
1678 2nd BOOTP request: delay 0 ... 2 sec
1679 3rd BOOTP request: delay 0 ... 4 sec
1681 BOOTP requests: delay 0 ... 8 sec
1683 - DHCP Advanced Options:
1684 You can fine tune the DHCP functionality by defining
1685 CONFIG_BOOTP_* symbols:
1687 CONFIG_BOOTP_SUBNETMASK
1688 CONFIG_BOOTP_GATEWAY
1689 CONFIG_BOOTP_HOSTNAME
1690 CONFIG_BOOTP_NISDOMAIN
1691 CONFIG_BOOTP_BOOTPATH
1692 CONFIG_BOOTP_BOOTFILESIZE
1695 CONFIG_BOOTP_SEND_HOSTNAME
1696 CONFIG_BOOTP_NTPSERVER
1697 CONFIG_BOOTP_TIMEOFFSET
1698 CONFIG_BOOTP_VENDOREX
1699 CONFIG_BOOTP_MAY_FAIL
1701 CONFIG_BOOTP_SERVERIP - TFTP server will be the serverip
1702 environment variable, not the BOOTP server.
1704 CONFIG_BOOTP_MAY_FAIL - If the DHCP server is not found
1705 after the configured retry count, the call will fail
1706 instead of starting over. This can be used to fail over
1707 to Link-local IP address configuration if the DHCP server
1710 CONFIG_BOOTP_DNS2 - If a DHCP client requests the DNS
1711 serverip from a DHCP server, it is possible that more
1712 than one DNS serverip is offered to the client.
1713 If CONFIG_BOOTP_DNS2 is enabled, the secondary DNS
1714 serverip will be stored in the additional environment
1715 variable "dnsip2". The first DNS serverip is always
1716 stored in the variable "dnsip", when CONFIG_BOOTP_DNS
1719 CONFIG_BOOTP_SEND_HOSTNAME - Some DHCP servers are capable
1720 to do a dynamic update of a DNS server. To do this, they
1721 need the hostname of the DHCP requester.
1722 If CONFIG_BOOTP_SEND_HOSTNAME is defined, the content
1723 of the "hostname" environment variable is passed as
1724 option 12 to the DHCP server.
1726 CONFIG_BOOTP_DHCP_REQUEST_DELAY
1728 A 32bit value in microseconds for a delay between
1729 receiving a "DHCP Offer" and sending the "DHCP Request".
1730 This fixes a problem with certain DHCP servers that don't
1731 respond 100% of the time to a "DHCP request". E.g. On an
1732 AT91RM9200 processor running at 180MHz, this delay needed
1733 to be *at least* 15,000 usec before a Windows Server 2003
1734 DHCP server would reply 100% of the time. I recommend at
1735 least 50,000 usec to be safe. The alternative is to hope
1736 that one of the retries will be successful but note that
1737 the DHCP timeout and retry process takes a longer than
1740 - Link-local IP address negotiation:
1741 Negotiate with other link-local clients on the local network
1742 for an address that doesn't require explicit configuration.
1743 This is especially useful if a DHCP server cannot be guaranteed
1744 to exist in all environments that the device must operate.
1746 See doc/README.link-local for more information.
1749 CONFIG_CDP_DEVICE_ID
1751 The device id used in CDP trigger frames.
1753 CONFIG_CDP_DEVICE_ID_PREFIX
1755 A two character string which is prefixed to the MAC address
1760 A printf format string which contains the ascii name of
1761 the port. Normally is set to "eth%d" which sets
1762 eth0 for the first Ethernet, eth1 for the second etc.
1764 CONFIG_CDP_CAPABILITIES
1766 A 32bit integer which indicates the device capabilities;
1767 0x00000010 for a normal host which does not forwards.
1771 An ascii string containing the version of the software.
1775 An ascii string containing the name of the platform.
1779 A 32bit integer sent on the trigger.
1781 CONFIG_CDP_POWER_CONSUMPTION
1783 A 16bit integer containing the power consumption of the
1784 device in .1 of milliwatts.
1786 CONFIG_CDP_APPLIANCE_VLAN_TYPE
1788 A byte containing the id of the VLAN.
1790 - Status LED: CONFIG_STATUS_LED
1792 Several configurations allow to display the current
1793 status using a LED. For instance, the LED will blink
1794 fast while running U-Boot code, stop blinking as
1795 soon as a reply to a BOOTP request was received, and
1796 start blinking slow once the Linux kernel is running
1797 (supported by a status LED driver in the Linux
1798 kernel). Defining CONFIG_STATUS_LED enables this
1801 - CAN Support: CONFIG_CAN_DRIVER
1803 Defining CONFIG_CAN_DRIVER enables CAN driver support
1804 on those systems that support this (optional)
1805 feature, like the TQM8xxL modules.
1807 - I2C Support: CONFIG_HARD_I2C | CONFIG_SOFT_I2C
1809 These enable I2C serial bus commands. Defining either of
1810 (but not both of) CONFIG_HARD_I2C or CONFIG_SOFT_I2C will
1811 include the appropriate I2C driver for the selected CPU.
1813 This will allow you to use i2c commands at the u-boot
1814 command line (as long as you set CONFIG_CMD_I2C in
1815 CONFIG_COMMANDS) and communicate with i2c based realtime
1816 clock chips. See common/cmd_i2c.c for a description of the
1817 command line interface.
1819 CONFIG_HARD_I2C selects a hardware I2C controller.
1821 CONFIG_SOFT_I2C configures u-boot to use a software (aka
1822 bit-banging) driver instead of CPM or similar hardware
1825 There are several other quantities that must also be
1826 defined when you define CONFIG_HARD_I2C or CONFIG_SOFT_I2C.
1828 In both cases you will need to define CONFIG_SYS_I2C_SPEED
1829 to be the frequency (in Hz) at which you wish your i2c bus
1830 to run and CONFIG_SYS_I2C_SLAVE to be the address of this node (ie
1831 the CPU's i2c node address).
1833 Now, the u-boot i2c code for the mpc8xx
1834 (arch/powerpc/cpu/mpc8xx/i2c.c) sets the CPU up as a master node
1835 and so its address should therefore be cleared to 0 (See,
1836 eg, MPC823e User's Manual p.16-473). So, set
1837 CONFIG_SYS_I2C_SLAVE to 0.
1839 CONFIG_SYS_I2C_INIT_MPC5XXX
1841 When a board is reset during an i2c bus transfer
1842 chips might think that the current transfer is still
1843 in progress. Reset the slave devices by sending start
1844 commands until the slave device responds.
1846 That's all that's required for CONFIG_HARD_I2C.
1848 If you use the software i2c interface (CONFIG_SOFT_I2C)
1849 then the following macros need to be defined (examples are
1850 from include/configs/lwmon.h):
1854 (Optional). Any commands necessary to enable the I2C
1855 controller or configure ports.
1857 eg: #define I2C_INIT (immr->im_cpm.cp_pbdir |= PB_SCL)
1861 (Only for MPC8260 CPU). The I/O port to use (the code
1862 assumes both bits are on the same port). Valid values
1863 are 0..3 for ports A..D.
1867 The code necessary to make the I2C data line active
1868 (driven). If the data line is open collector, this
1871 eg: #define I2C_ACTIVE (immr->im_cpm.cp_pbdir |= PB_SDA)
1875 The code necessary to make the I2C data line tri-stated
1876 (inactive). If the data line is open collector, this
1879 eg: #define I2C_TRISTATE (immr->im_cpm.cp_pbdir &= ~PB_SDA)
1883 Code that returns TRUE if the I2C data line is high,
1886 eg: #define I2C_READ ((immr->im_cpm.cp_pbdat & PB_SDA) != 0)
1890 If <bit> is TRUE, sets the I2C data line high. If it
1891 is FALSE, it clears it (low).
1893 eg: #define I2C_SDA(bit) \
1894 if(bit) immr->im_cpm.cp_pbdat |= PB_SDA; \
1895 else immr->im_cpm.cp_pbdat &= ~PB_SDA
1899 If <bit> is TRUE, sets the I2C clock line high. If it
1900 is FALSE, it clears it (low).
1902 eg: #define I2C_SCL(bit) \
1903 if(bit) immr->im_cpm.cp_pbdat |= PB_SCL; \
1904 else immr->im_cpm.cp_pbdat &= ~PB_SCL
1908 This delay is invoked four times per clock cycle so this
1909 controls the rate of data transfer. The data rate thus
1910 is 1 / (I2C_DELAY * 4). Often defined to be something
1913 #define I2C_DELAY udelay(2)
1915 CONFIG_SOFT_I2C_GPIO_SCL / CONFIG_SOFT_I2C_GPIO_SDA
1917 If your arch supports the generic GPIO framework (asm/gpio.h),
1918 then you may alternatively define the two GPIOs that are to be
1919 used as SCL / SDA. Any of the previous I2C_xxx macros will
1920 have GPIO-based defaults assigned to them as appropriate.
1922 You should define these to the GPIO value as given directly to
1923 the generic GPIO functions.
1925 CONFIG_SYS_I2C_INIT_BOARD
1927 When a board is reset during an i2c bus transfer
1928 chips might think that the current transfer is still
1929 in progress. On some boards it is possible to access
1930 the i2c SCLK line directly, either by using the
1931 processor pin as a GPIO or by having a second pin
1932 connected to the bus. If this option is defined a
1933 custom i2c_init_board() routine in boards/xxx/board.c
1934 is run early in the boot sequence.
1936 CONFIG_SYS_I2C_BOARD_LATE_INIT
1938 An alternative to CONFIG_SYS_I2C_INIT_BOARD. If this option is
1939 defined a custom i2c_board_late_init() routine in
1940 boards/xxx/board.c is run AFTER the operations in i2c_init()
1941 is completed. This callpoint can be used to unreset i2c bus
1942 using CPU i2c controller register accesses for CPUs whose i2c
1943 controller provide such a method. It is called at the end of
1944 i2c_init() to allow i2c_init operations to setup the i2c bus
1945 controller on the CPU (e.g. setting bus speed & slave address).
1947 CONFIG_I2CFAST (PPC405GP|PPC405EP only)
1949 This option enables configuration of bi_iic_fast[] flags
1950 in u-boot bd_info structure based on u-boot environment
1951 variable "i2cfast". (see also i2cfast)
1953 CONFIG_I2C_MULTI_BUS
1955 This option allows the use of multiple I2C buses, each of which
1956 must have a controller. At any point in time, only one bus is
1957 active. To switch to a different bus, use the 'i2c dev' command.
1958 Note that bus numbering is zero-based.
1960 CONFIG_SYS_I2C_NOPROBES
1962 This option specifies a list of I2C devices that will be skipped
1963 when the 'i2c probe' command is issued. If CONFIG_I2C_MULTI_BUS
1964 is set, specify a list of bus-device pairs. Otherwise, specify
1965 a 1D array of device addresses
1968 #undef CONFIG_I2C_MULTI_BUS
1969 #define CONFIG_SYS_I2C_NOPROBES {0x50,0x68}
1971 will skip addresses 0x50 and 0x68 on a board with one I2C bus
1973 #define CONFIG_I2C_MULTI_BUS
1974 #define CONFIG_SYS_I2C_MULTI_NOPROBES {{0,0x50},{0,0x68},{1,0x54}}
1976 will skip addresses 0x50 and 0x68 on bus 0 and address 0x54 on bus 1
1978 CONFIG_SYS_SPD_BUS_NUM
1980 If defined, then this indicates the I2C bus number for DDR SPD.
1981 If not defined, then U-Boot assumes that SPD is on I2C bus 0.
1983 CONFIG_SYS_RTC_BUS_NUM
1985 If defined, then this indicates the I2C bus number for the RTC.
1986 If not defined, then U-Boot assumes that RTC is on I2C bus 0.
1988 CONFIG_SYS_DTT_BUS_NUM
1990 If defined, then this indicates the I2C bus number for the DTT.
1991 If not defined, then U-Boot assumes that DTT is on I2C bus 0.
1993 CONFIG_SYS_I2C_DTT_ADDR:
1995 If defined, specifies the I2C address of the DTT device.
1996 If not defined, then U-Boot uses predefined value for
1997 specified DTT device.
2001 Define this option if you want to use Freescale's I2C driver in
2002 drivers/i2c/fsl_i2c.c.
2006 Define this option if you have I2C devices reached over 1 .. n
2007 I2C Muxes like the pca9544a. This option addes a new I2C
2008 Command "i2c bus [muxtype:muxaddr:muxchannel]" which adds a
2009 new I2C Bus to the existing I2C Busses. If you select the
2010 new Bus with "i2c dev", u-bbot sends first the commandos for
2011 the muxes to activate this new "bus".
2013 CONFIG_I2C_MULTI_BUS must be also defined, to use this
2017 Adding a new I2C Bus reached over 2 pca9544a muxes
2018 The First mux with address 70 and channel 6
2019 The Second mux with address 71 and channel 4
2021 => i2c bus pca9544a:70:6:pca9544a:71:4
2023 Use the "i2c bus" command without parameter, to get a list
2024 of I2C Busses with muxes:
2027 Busses reached over muxes:
2029 reached over Mux(es):
2032 reached over Mux(es):
2037 If you now switch to the new I2C Bus 3 with "i2c dev 3"
2038 u-boot first sends the command to the mux@70 to enable
2039 channel 6, and then the command to the mux@71 to enable
2042 After that, you can use the "normal" i2c commands as
2043 usual to communicate with your I2C devices behind
2046 This option is actually implemented for the bitbanging
2047 algorithm in common/soft_i2c.c and for the Hardware I2C
2048 Bus on the MPC8260. But it should be not so difficult
2049 to add this option to other architectures.
2051 CONFIG_SOFT_I2C_READ_REPEATED_START
2053 defining this will force the i2c_read() function in
2054 the soft_i2c driver to perform an I2C repeated start
2055 between writing the address pointer and reading the
2056 data. If this define is omitted the default behaviour
2057 of doing a stop-start sequence will be used. Most I2C
2058 devices can use either method, but some require one or
2061 - SPI Support: CONFIG_SPI
2063 Enables SPI driver (so far only tested with
2064 SPI EEPROM, also an instance works with Crystal A/D and
2065 D/As on the SACSng board)
2069 Enables the driver for SPI controller on SuperH. Currently
2070 only SH7757 is supported.
2074 Enables extended (16-bit) SPI EEPROM addressing.
2075 (symmetrical to CONFIG_I2C_X)
2079 Enables a software (bit-bang) SPI driver rather than
2080 using hardware support. This is a general purpose
2081 driver that only requires three general I/O port pins
2082 (two outputs, one input) to function. If this is
2083 defined, the board configuration must define several
2084 SPI configuration items (port pins to use, etc). For
2085 an example, see include/configs/sacsng.h.
2089 Enables a hardware SPI driver for general-purpose reads
2090 and writes. As with CONFIG_SOFT_SPI, the board configuration
2091 must define a list of chip-select function pointers.
2092 Currently supported on some MPC8xxx processors. For an
2093 example, see include/configs/mpc8349emds.h.
2097 Enables the driver for the SPI controllers on i.MX and MXC
2098 SoCs. Currently i.MX31/35/51 are supported.
2100 - FPGA Support: CONFIG_FPGA
2102 Enables FPGA subsystem.
2104 CONFIG_FPGA_<vendor>
2106 Enables support for specific chip vendors.
2109 CONFIG_FPGA_<family>
2111 Enables support for FPGA family.
2112 (SPARTAN2, SPARTAN3, VIRTEX2, CYCLONE2, ACEX1K, ACEX)
2116 Specify the number of FPGA devices to support.
2118 CONFIG_SYS_FPGA_PROG_FEEDBACK
2120 Enable printing of hash marks during FPGA configuration.
2122 CONFIG_SYS_FPGA_CHECK_BUSY
2124 Enable checks on FPGA configuration interface busy
2125 status by the configuration function. This option
2126 will require a board or device specific function to
2131 If defined, a function that provides delays in the FPGA
2132 configuration driver.
2134 CONFIG_SYS_FPGA_CHECK_CTRLC
2135 Allow Control-C to interrupt FPGA configuration
2137 CONFIG_SYS_FPGA_CHECK_ERROR
2139 Check for configuration errors during FPGA bitfile
2140 loading. For example, abort during Virtex II
2141 configuration if the INIT_B line goes low (which
2142 indicated a CRC error).
2144 CONFIG_SYS_FPGA_WAIT_INIT
2146 Maximum time to wait for the INIT_B line to deassert
2147 after PROB_B has been deasserted during a Virtex II
2148 FPGA configuration sequence. The default time is 500
2151 CONFIG_SYS_FPGA_WAIT_BUSY
2153 Maximum time to wait for BUSY to deassert during
2154 Virtex II FPGA configuration. The default is 5 ms.
2156 CONFIG_SYS_FPGA_WAIT_CONFIG
2158 Time to wait after FPGA configuration. The default is
2161 - Configuration Management:
2164 If defined, this string will be added to the U-Boot
2165 version information (U_BOOT_VERSION)
2167 - Vendor Parameter Protection:
2169 U-Boot considers the values of the environment
2170 variables "serial#" (Board Serial Number) and
2171 "ethaddr" (Ethernet Address) to be parameters that
2172 are set once by the board vendor / manufacturer, and
2173 protects these variables from casual modification by
2174 the user. Once set, these variables are read-only,
2175 and write or delete attempts are rejected. You can
2176 change this behaviour:
2178 If CONFIG_ENV_OVERWRITE is #defined in your config
2179 file, the write protection for vendor parameters is
2180 completely disabled. Anybody can change or delete
2183 Alternatively, if you #define _both_ CONFIG_ETHADDR
2184 _and_ CONFIG_OVERWRITE_ETHADDR_ONCE, a default
2185 Ethernet address is installed in the environment,
2186 which can be changed exactly ONCE by the user. [The
2187 serial# is unaffected by this, i. e. it remains
2193 Define this variable to enable the reservation of
2194 "protected RAM", i. e. RAM which is not overwritten
2195 by U-Boot. Define CONFIG_PRAM to hold the number of
2196 kB you want to reserve for pRAM. You can overwrite
2197 this default value by defining an environment
2198 variable "pram" to the number of kB you want to
2199 reserve. Note that the board info structure will
2200 still show the full amount of RAM. If pRAM is
2201 reserved, a new environment variable "mem" will
2202 automatically be defined to hold the amount of
2203 remaining RAM in a form that can be passed as boot
2204 argument to Linux, for instance like that:
2206 setenv bootargs ... mem=\${mem}
2209 This way you can tell Linux not to use this memory,
2210 either, which results in a memory region that will
2211 not be affected by reboots.
2213 *WARNING* If your board configuration uses automatic
2214 detection of the RAM size, you must make sure that
2215 this memory test is non-destructive. So far, the
2216 following board configurations are known to be
2219 IVMS8, IVML24, SPD8xx, TQM8xxL,
2220 HERMES, IP860, RPXlite, LWMON,
2223 - Access to physical memory region (> 4GB)
2224 Some basic support is provided for operations on memory not
2225 normally accessible to U-Boot - e.g. some architectures
2226 support access to more than 4GB of memory on 32-bit
2227 machines using physical address extension or similar.
2228 Define CONFIG_PHYSMEM to access this basic support, which
2229 currently only supports clearing the memory.
2234 Define this variable to stop the system in case of a
2235 fatal error, so that you have to reset it manually.
2236 This is probably NOT a good idea for an embedded
2237 system where you want the system to reboot
2238 automatically as fast as possible, but it may be
2239 useful during development since you can try to debug
2240 the conditions that lead to the situation.
2242 CONFIG_NET_RETRY_COUNT
2244 This variable defines the number of retries for
2245 network operations like ARP, RARP, TFTP, or BOOTP
2246 before giving up the operation. If not defined, a
2247 default value of 5 is used.
2251 Timeout waiting for an ARP reply in milliseconds.
2255 Timeout in milliseconds used in NFS protocol.
2256 If you encounter "ERROR: Cannot umount" in nfs command,
2257 try longer timeout such as
2258 #define CONFIG_NFS_TIMEOUT 10000UL
2260 - Command Interpreter:
2261 CONFIG_AUTO_COMPLETE
2263 Enable auto completion of commands using TAB.
2265 Note that this feature has NOT been implemented yet
2266 for the "hush" shell.
2269 CONFIG_SYS_HUSH_PARSER
2271 Define this variable to enable the "hush" shell (from
2272 Busybox) as command line interpreter, thus enabling
2273 powerful command line syntax like
2274 if...then...else...fi conditionals or `&&' and '||'
2275 constructs ("shell scripts").
2277 If undefined, you get the old, much simpler behaviour
2278 with a somewhat smaller memory footprint.
2281 CONFIG_SYS_PROMPT_HUSH_PS2
2283 This defines the secondary prompt string, which is
2284 printed when the command interpreter needs more input
2285 to complete a command. Usually "> ".
2289 In the current implementation, the local variables
2290 space and global environment variables space are
2291 separated. Local variables are those you define by
2292 simply typing `name=value'. To access a local
2293 variable later on, you have write `$name' or
2294 `${name}'; to execute the contents of a variable
2295 directly type `$name' at the command prompt.
2297 Global environment variables are those you use
2298 setenv/printenv to work with. To run a command stored
2299 in such a variable, you need to use the run command,
2300 and you must not use the '$' sign to access them.
2302 To store commands and special characters in a
2303 variable, please use double quotation marks
2304 surrounding the whole text of the variable, instead
2305 of the backslashes before semicolons and special
2308 - Commandline Editing and History:
2309 CONFIG_CMDLINE_EDITING
2311 Enable editing and History functions for interactive
2312 commandline input operations
2314 - Default Environment:
2315 CONFIG_EXTRA_ENV_SETTINGS
2317 Define this to contain any number of null terminated
2318 strings (variable = value pairs) that will be part of
2319 the default environment compiled into the boot image.
2321 For example, place something like this in your
2322 board's config file:
2324 #define CONFIG_EXTRA_ENV_SETTINGS \
2328 Warning: This method is based on knowledge about the
2329 internal format how the environment is stored by the
2330 U-Boot code. This is NOT an official, exported
2331 interface! Although it is unlikely that this format
2332 will change soon, there is no guarantee either.
2333 You better know what you are doing here.
2335 Note: overly (ab)use of the default environment is
2336 discouraged. Make sure to check other ways to preset
2337 the environment like the "source" command or the
2340 CONFIG_ENV_VARS_UBOOT_CONFIG
2342 Define this in order to add variables describing the
2343 U-Boot build configuration to the default environment.
2344 These will be named arch, cpu, board, vendor, and soc.
2346 Enabling this option will cause the following to be defined:
2354 CONFIG_ENV_VARS_UBOOT_RUNTIME_CONFIG
2356 Define this in order to add variables describing certain
2357 run-time determined information about the hardware to the
2358 environment. These will be named board_name, board_rev.
2360 - DataFlash Support:
2361 CONFIG_HAS_DATAFLASH
2363 Defining this option enables DataFlash features and
2364 allows to read/write in Dataflash via the standard
2367 - Serial Flash support
2370 Defining this option enables SPI flash commands
2371 'sf probe/read/write/erase/update'.
2373 Usage requires an initial 'probe' to define the serial
2374 flash parameters, followed by read/write/erase/update
2377 The following defaults may be provided by the platform
2378 to handle the common case when only a single serial
2379 flash is present on the system.
2381 CONFIG_SF_DEFAULT_BUS Bus identifier
2382 CONFIG_SF_DEFAULT_CS Chip-select
2383 CONFIG_SF_DEFAULT_MODE (see include/spi.h)
2384 CONFIG_SF_DEFAULT_SPEED in Hz
2386 - SystemACE Support:
2389 Adding this option adds support for Xilinx SystemACE
2390 chips attached via some sort of local bus. The address
2391 of the chip must also be defined in the
2392 CONFIG_SYS_SYSTEMACE_BASE macro. For example:
2394 #define CONFIG_SYSTEMACE
2395 #define CONFIG_SYS_SYSTEMACE_BASE 0xf0000000
2397 When SystemACE support is added, the "ace" device type
2398 becomes available to the fat commands, i.e. fatls.
2400 - TFTP Fixed UDP Port:
2403 If this is defined, the environment variable tftpsrcp
2404 is used to supply the TFTP UDP source port value.
2405 If tftpsrcp isn't defined, the normal pseudo-random port
2406 number generator is used.
2408 Also, the environment variable tftpdstp is used to supply
2409 the TFTP UDP destination port value. If tftpdstp isn't
2410 defined, the normal port 69 is used.
2412 The purpose for tftpsrcp is to allow a TFTP server to
2413 blindly start the TFTP transfer using the pre-configured
2414 target IP address and UDP port. This has the effect of
2415 "punching through" the (Windows XP) firewall, allowing
2416 the remainder of the TFTP transfer to proceed normally.
2417 A better solution is to properly configure the firewall,
2418 but sometimes that is not allowed.
2423 This enables a generic 'hash' command which can produce
2424 hashes / digests from a few algorithms (e.g. SHA1, SHA256).
2428 Enable the hash verify command (hash -v). This adds to code
2431 CONFIG_SHA1 - support SHA1 hashing
2432 CONFIG_SHA256 - support SHA256 hashing
2434 Note: There is also a sha1sum command, which should perhaps
2435 be deprecated in favour of 'hash sha1'.
2437 - Show boot progress:
2438 CONFIG_SHOW_BOOT_PROGRESS
2440 Defining this option allows to add some board-
2441 specific code (calling a user-provided function
2442 "show_boot_progress(int)") that enables you to show
2443 the system's boot progress on some display (for
2444 example, some LED's) on your board. At the moment,
2445 the following checkpoints are implemented:
2447 - Detailed boot stage timing
2449 Define this option to get detailed timing of each stage
2450 of the boot process.
2452 CONFIG_BOOTSTAGE_USER_COUNT
2453 This is the number of available user bootstage records.
2454 Each time you call bootstage_mark(BOOTSTAGE_ID_ALLOC, ...)
2455 a new ID will be allocated from this stash. If you exceed
2456 the limit, recording will stop.
2458 CONFIG_BOOTSTAGE_REPORT
2459 Define this to print a report before boot, similar to this:
2461 Timer summary in microseconds:
2464 3,575,678 3,575,678 board_init_f start
2465 3,575,695 17 arch_cpu_init A9
2466 3,575,777 82 arch_cpu_init done
2467 3,659,598 83,821 board_init_r start
2468 3,910,375 250,777 main_loop
2469 29,916,167 26,005,792 bootm_start
2470 30,361,327 445,160 start_kernel
2472 CONFIG_CMD_BOOTSTAGE
2473 Add a 'bootstage' command which supports printing a report
2474 and un/stashing of bootstage data.
2476 CONFIG_BOOTSTAGE_FDT
2477 Stash the bootstage information in the FDT. A root 'bootstage'
2478 node is created with each bootstage id as a child. Each child
2479 has a 'name' property and either 'mark' containing the
2480 mark time in microsecond, or 'accum' containing the
2481 accumulated time for that bootstage id in microseconds.
2486 name = "board_init_f";
2495 Code in the Linux kernel can find this in /proc/devicetree.
2497 Legacy uImage format:
2500 1 common/cmd_bootm.c before attempting to boot an image
2501 -1 common/cmd_bootm.c Image header has bad magic number
2502 2 common/cmd_bootm.c Image header has correct magic number
2503 -2 common/cmd_bootm.c Image header has bad checksum
2504 3 common/cmd_bootm.c Image header has correct checksum
2505 -3 common/cmd_bootm.c Image data has bad checksum
2506 4 common/cmd_bootm.c Image data has correct checksum
2507 -4 common/cmd_bootm.c Image is for unsupported architecture
2508 5 common/cmd_bootm.c Architecture check OK
2509 -5 common/cmd_bootm.c Wrong Image Type (not kernel, multi)
2510 6 common/cmd_bootm.c Image Type check OK
2511 -6 common/cmd_bootm.c gunzip uncompression error
2512 -7 common/cmd_bootm.c Unimplemented compression type
2513 7 common/cmd_bootm.c Uncompression OK
2514 8 common/cmd_bootm.c No uncompress/copy overwrite error
2515 -9 common/cmd_bootm.c Unsupported OS (not Linux, BSD, VxWorks, QNX)
2517 9 common/image.c Start initial ramdisk verification
2518 -10 common/image.c Ramdisk header has bad magic number
2519 -11 common/image.c Ramdisk header has bad checksum
2520 10 common/image.c Ramdisk header is OK
2521 -12 common/image.c Ramdisk data has bad checksum
2522 11 common/image.c Ramdisk data has correct checksum
2523 12 common/image.c Ramdisk verification complete, start loading
2524 -13 common/image.c Wrong Image Type (not PPC Linux ramdisk)
2525 13 common/image.c Start multifile image verification
2526 14 common/image.c No initial ramdisk, no multifile, continue.
2528 15 arch/<arch>/lib/bootm.c All preparation done, transferring control to OS
2530 -30 arch/powerpc/lib/board.c Fatal error, hang the system
2531 -31 post/post.c POST test failed, detected by post_output_backlog()
2532 -32 post/post.c POST test failed, detected by post_run_single()
2534 34 common/cmd_doc.c before loading a Image from a DOC device
2535 -35 common/cmd_doc.c Bad usage of "doc" command
2536 35 common/cmd_doc.c correct usage of "doc" command
2537 -36 common/cmd_doc.c No boot device
2538 36 common/cmd_doc.c correct boot device
2539 -37 common/cmd_doc.c Unknown Chip ID on boot device
2540 37 common/cmd_doc.c correct chip ID found, device available
2541 -38 common/cmd_doc.c Read Error on boot device
2542 38 common/cmd_doc.c reading Image header from DOC device OK
2543 -39 common/cmd_doc.c Image header has bad magic number
2544 39 common/cmd_doc.c Image header has correct magic number
2545 -40 common/cmd_doc.c Error reading Image from DOC device
2546 40 common/cmd_doc.c Image header has correct magic number
2547 41 common/cmd_ide.c before loading a Image from a IDE device
2548 -42 common/cmd_ide.c Bad usage of "ide" command
2549 42 common/cmd_ide.c correct usage of "ide" command
2550 -43 common/cmd_ide.c No boot device
2551 43 common/cmd_ide.c boot device found
2552 -44 common/cmd_ide.c Device not available
2553 44 common/cmd_ide.c Device available
2554 -45 common/cmd_ide.c wrong partition selected
2555 45 common/cmd_ide.c partition selected
2556 -46 common/cmd_ide.c Unknown partition table
2557 46 common/cmd_ide.c valid partition table found
2558 -47 common/cmd_ide.c Invalid partition type
2559 47 common/cmd_ide.c correct partition type
2560 -48 common/cmd_ide.c Error reading Image Header on boot device
2561 48 common/cmd_ide.c reading Image Header from IDE device OK
2562 -49 common/cmd_ide.c Image header has bad magic number
2563 49 common/cmd_ide.c Image header has correct magic number
2564 -50 common/cmd_ide.c Image header has bad checksum
2565 50 common/cmd_ide.c Image header has correct checksum
2566 -51 common/cmd_ide.c Error reading Image from IDE device
2567 51 common/cmd_ide.c reading Image from IDE device OK
2568 52 common/cmd_nand.c before loading a Image from a NAND device
2569 -53 common/cmd_nand.c Bad usage of "nand" command
2570 53 common/cmd_nand.c correct usage of "nand" command
2571 -54 common/cmd_nand.c No boot device
2572 54 common/cmd_nand.c boot device found
2573 -55 common/cmd_nand.c Unknown Chip ID on boot device
2574 55 common/cmd_nand.c correct chip ID found, device available
2575 -56 common/cmd_nand.c Error reading Image Header on boot device
2576 56 common/cmd_nand.c reading Image Header from NAND device OK
2577 -57 common/cmd_nand.c Image header has bad magic number
2578 57 common/cmd_nand.c Image header has correct magic number
2579 -58 common/cmd_nand.c Error reading Image from NAND device
2580 58 common/cmd_nand.c reading Image from NAND device OK
2582 -60 common/env_common.c Environment has a bad CRC, using default
2584 64 net/eth.c starting with Ethernet configuration.
2585 -64 net/eth.c no Ethernet found.
2586 65 net/eth.c Ethernet found.
2588 -80 common/cmd_net.c usage wrong
2589 80 common/cmd_net.c before calling NetLoop()
2590 -81 common/cmd_net.c some error in NetLoop() occurred
2591 81 common/cmd_net.c NetLoop() back without error
2592 -82 common/cmd_net.c size == 0 (File with size 0 loaded)
2593 82 common/cmd_net.c trying automatic boot
2594 83 common/cmd_net.c running "source" command
2595 -83 common/cmd_net.c some error in automatic boot or "source" command
2596 84 common/cmd_net.c end without errors
2601 100 common/cmd_bootm.c Kernel FIT Image has correct format
2602 -100 common/cmd_bootm.c Kernel FIT Image has incorrect format
2603 101 common/cmd_bootm.c No Kernel subimage unit name, using configuration
2604 -101 common/cmd_bootm.c Can't get configuration for kernel subimage
2605 102 common/cmd_bootm.c Kernel unit name specified
2606 -103 common/cmd_bootm.c Can't get kernel subimage node offset
2607 103 common/cmd_bootm.c Found configuration node
2608 104 common/cmd_bootm.c Got kernel subimage node offset
2609 -104 common/cmd_bootm.c Kernel subimage hash verification failed
2610 105 common/cmd_bootm.c Kernel subimage hash verification OK
2611 -105 common/cmd_bootm.c Kernel subimage is for unsupported architecture
2612 106 common/cmd_bootm.c Architecture check OK
2613 -106 common/cmd_bootm.c Kernel subimage has wrong type
2614 107 common/cmd_bootm.c Kernel subimage type OK
2615 -107 common/cmd_bootm.c Can't get kernel subimage data/size
2616 108 common/cmd_bootm.c Got kernel subimage data/size
2617 -108 common/cmd_bootm.c Wrong image type (not legacy, FIT)
2618 -109 common/cmd_bootm.c Can't get kernel subimage type
2619 -110 common/cmd_bootm.c Can't get kernel subimage comp
2620 -111 common/cmd_bootm.c Can't get kernel subimage os
2621 -112 common/cmd_bootm.c Can't get kernel subimage load address
2622 -113 common/cmd_bootm.c Image uncompress/copy overwrite error
2624 120 common/image.c Start initial ramdisk verification
2625 -120 common/image.c Ramdisk FIT image has incorrect format
2626 121 common/image.c Ramdisk FIT image has correct format
2627 122 common/image.c No ramdisk subimage unit name, using configuration
2628 -122 common/image.c Can't get configuration for ramdisk subimage
2629 123 common/image.c Ramdisk unit name specified
2630 -124 common/image.c Can't get ramdisk subimage node offset
2631 125 common/image.c Got ramdisk subimage node offset
2632 -125 common/image.c Ramdisk subimage hash verification failed
2633 126 common/image.c Ramdisk subimage hash verification OK
2634 -126 common/image.c Ramdisk subimage for unsupported architecture
2635 127 common/image.c Architecture check OK
2636 -127 common/image.c Can't get ramdisk subimage data/size
2637 128 common/image.c Got ramdisk subimage data/size
2638 129 common/image.c Can't get ramdisk load address
2639 -129 common/image.c Got ramdisk load address
2641 -130 common/cmd_doc.c Incorrect FIT image format
2642 131 common/cmd_doc.c FIT image format OK
2644 -140 common/cmd_ide.c Incorrect FIT image format
2645 141 common/cmd_ide.c FIT image format OK
2647 -150 common/cmd_nand.c Incorrect FIT image format
2648 151 common/cmd_nand.c FIT image format OK
2650 - FIT image support:
2652 Enable support for the FIT uImage format.
2654 CONFIG_FIT_BEST_MATCH
2655 When no configuration is explicitly selected, default to the
2656 one whose fdt's compatibility field best matches that of
2657 U-Boot itself. A match is considered "best" if it matches the
2658 most specific compatibility entry of U-Boot's fdt's root node.
2659 The order of entries in the configuration's fdt is ignored.
2661 - Standalone program support:
2662 CONFIG_STANDALONE_LOAD_ADDR
2664 This option defines a board specific value for the
2665 address where standalone program gets loaded, thus
2666 overwriting the architecture dependent default
2669 - Frame Buffer Address:
2672 Define CONFIG_FB_ADDR if you want to use specific
2673 address for frame buffer.
2674 Then system will reserve the frame buffer address to
2675 defined address instead of lcd_setmem (this function
2676 grabs the memory for frame buffer by panel's size).
2678 Please see board_init_f function.
2680 - Automatic software updates via TFTP server
2682 CONFIG_UPDATE_TFTP_CNT_MAX
2683 CONFIG_UPDATE_TFTP_MSEC_MAX
2685 These options enable and control the auto-update feature;
2686 for a more detailed description refer to doc/README.update.
2688 - MTD Support (mtdparts command, UBI support)
2691 Adds the MTD device infrastructure from the Linux kernel.
2692 Needed for mtdparts command support.
2694 CONFIG_MTD_PARTITIONS
2696 Adds the MTD partitioning infrastructure from the Linux
2697 kernel. Needed for UBI support.
2701 Enable building of SPL globally.
2704 LDSCRIPT for linking the SPL binary.
2707 Maximum binary size (text, data and rodata) of the SPL binary.
2709 CONFIG_SPL_TEXT_BASE
2710 TEXT_BASE for linking the SPL binary.
2712 CONFIG_SPL_RELOC_TEXT_BASE
2713 Address to relocate to. If unspecified, this is equal to
2714 CONFIG_SPL_TEXT_BASE (i.e. no relocation is done).
2716 CONFIG_SPL_BSS_START_ADDR
2717 Link address for the BSS within the SPL binary.
2719 CONFIG_SPL_BSS_MAX_SIZE
2720 Maximum binary size of the BSS section of the SPL binary.
2723 Adress of the start of the stack SPL will use
2725 CONFIG_SPL_RELOC_STACK
2726 Adress of the start of the stack SPL will use after
2727 relocation. If unspecified, this is equal to
2730 CONFIG_SYS_SPL_MALLOC_START
2731 Starting address of the malloc pool used in SPL.
2733 CONFIG_SYS_SPL_MALLOC_SIZE
2734 The size of the malloc pool used in SPL.
2736 CONFIG_SPL_FRAMEWORK
2737 Enable the SPL framework under common/. This framework
2738 supports MMC, NAND and YMODEM loading of U-Boot and NAND
2739 NAND loading of the Linux Kernel.
2741 CONFIG_SPL_DISPLAY_PRINT
2742 For ARM, enable an optional function to print more information
2743 about the running system.
2745 CONFIG_SPL_INIT_MINIMAL
2746 Arch init code should be built for a very small image
2748 CONFIG_SPL_LIBCOMMON_SUPPORT
2749 Support for common/libcommon.o in SPL binary
2751 CONFIG_SPL_LIBDISK_SUPPORT
2752 Support for disk/libdisk.o in SPL binary
2754 CONFIG_SPL_I2C_SUPPORT
2755 Support for drivers/i2c/libi2c.o in SPL binary
2757 CONFIG_SPL_GPIO_SUPPORT
2758 Support for drivers/gpio/libgpio.o in SPL binary
2760 CONFIG_SPL_MMC_SUPPORT
2761 Support for drivers/mmc/libmmc.o in SPL binary
2763 CONFIG_SYS_MMCSD_RAW_MODE_U_BOOT_SECTOR,
2764 CONFIG_SYS_U_BOOT_MAX_SIZE_SECTORS,
2765 CONFIG_SYS_MMC_SD_FAT_BOOT_PARTITION
2766 Address, size and partition on the MMC to load U-Boot from
2767 when the MMC is being used in raw mode.
2769 CONFIG_SPL_FAT_SUPPORT
2770 Support for fs/fat/libfat.o in SPL binary
2772 CONFIG_SPL_FAT_LOAD_PAYLOAD_NAME
2773 Filename to read to load U-Boot when reading from FAT
2775 CONFIG_SPL_NAND_BASE
2776 Include nand_base.c in the SPL. Requires
2777 CONFIG_SPL_NAND_DRIVERS.
2779 CONFIG_SPL_NAND_DRIVERS
2780 SPL uses normal NAND drivers, not minimal drivers.
2783 Include standard software ECC in the SPL
2785 CONFIG_SPL_NAND_SIMPLE
2786 Support for NAND boot using simple NAND drivers that
2787 expose the cmd_ctrl() interface.
2789 CONFIG_SYS_NAND_5_ADDR_CYCLE, CONFIG_SYS_NAND_PAGE_COUNT,
2790 CONFIG_SYS_NAND_PAGE_SIZE, CONFIG_SYS_NAND_OOBSIZE,
2791 CONFIG_SYS_NAND_BLOCK_SIZE, CONFIG_SYS_NAND_BAD_BLOCK_POS,
2792 CONFIG_SYS_NAND_ECCPOS, CONFIG_SYS_NAND_ECCSIZE,
2793 CONFIG_SYS_NAND_ECCBYTES
2794 Defines the size and behavior of the NAND that SPL uses
2797 CONFIG_SYS_NAND_U_BOOT_OFFS
2798 Location in NAND to read U-Boot from
2800 CONFIG_SYS_NAND_U_BOOT_DST
2801 Location in memory to load U-Boot to
2803 CONFIG_SYS_NAND_U_BOOT_SIZE
2804 Size of image to load
2806 CONFIG_SYS_NAND_U_BOOT_START
2807 Entry point in loaded image to jump to
2809 CONFIG_SYS_NAND_HW_ECC_OOBFIRST
2810 Define this if you need to first read the OOB and then the
2811 data. This is used for example on davinci plattforms.
2813 CONFIG_SPL_OMAP3_ID_NAND
2814 Support for an OMAP3-specific set of functions to return the
2815 ID and MFR of the first attached NAND chip, if present.
2817 CONFIG_SPL_SERIAL_SUPPORT
2818 Support for drivers/serial/libserial.o in SPL binary
2820 CONFIG_SPL_SPI_FLASH_SUPPORT
2821 Support for drivers/mtd/spi/libspi_flash.o in SPL binary
2823 CONFIG_SPL_SPI_SUPPORT
2824 Support for drivers/spi/libspi.o in SPL binary
2826 CONFIG_SPL_RAM_DEVICE
2827 Support for running image already present in ram, in SPL binary
2829 CONFIG_SPL_LIBGENERIC_SUPPORT
2830 Support for lib/libgeneric.o in SPL binary
2833 Final target image containing SPL and payload. Some SPLs
2834 use an arch-specific makefile fragment instead, for
2835 example if more than one image needs to be produced.
2840 [so far only for SMDK2400 boards]
2842 - Modem support enable:
2843 CONFIG_MODEM_SUPPORT
2845 - RTS/CTS Flow control enable:
2848 - Modem debug support:
2849 CONFIG_MODEM_SUPPORT_DEBUG
2851 Enables debugging stuff (char screen[1024], dbg())
2852 for modem support. Useful only with BDI2000.
2854 - Interrupt support (PPC):
2856 There are common interrupt_init() and timer_interrupt()
2857 for all PPC archs. interrupt_init() calls interrupt_init_cpu()
2858 for CPU specific initialization. interrupt_init_cpu()
2859 should set decrementer_count to appropriate value. If
2860 CPU resets decrementer automatically after interrupt
2861 (ppc4xx) it should set decrementer_count to zero.
2862 timer_interrupt() calls timer_interrupt_cpu() for CPU
2863 specific handling. If board has watchdog / status_led
2864 / other_activity_monitor it works automatically from
2865 general timer_interrupt().
2869 In the target system modem support is enabled when a
2870 specific key (key combination) is pressed during
2871 power-on. Otherwise U-Boot will boot normally
2872 (autoboot). The key_pressed() function is called from
2873 board_init(). Currently key_pressed() is a dummy
2874 function, returning 1 and thus enabling modem
2877 If there are no modem init strings in the
2878 environment, U-Boot proceed to autoboot; the
2879 previous output (banner, info printfs) will be
2882 See also: doc/README.Modem
2884 Board initialization settings:
2885 ------------------------------
2887 During Initialization u-boot calls a number of board specific functions
2888 to allow the preparation of board specific prerequisites, e.g. pin setup
2889 before drivers are initialized. To enable these callbacks the
2890 following configuration macros have to be defined. Currently this is
2891 architecture specific, so please check arch/your_architecture/lib/board.c
2892 typically in board_init_f() and board_init_r().
2894 - CONFIG_BOARD_EARLY_INIT_F: Call board_early_init_f()
2895 - CONFIG_BOARD_EARLY_INIT_R: Call board_early_init_r()
2896 - CONFIG_BOARD_LATE_INIT: Call board_late_init()
2897 - CONFIG_BOARD_POSTCLK_INIT: Call board_postclk_init()
2899 Configuration Settings:
2900 -----------------------
2902 - CONFIG_SYS_LONGHELP: Defined when you want long help messages included;
2903 undefine this when you're short of memory.
2905 - CONFIG_SYS_HELP_CMD_WIDTH: Defined when you want to override the default
2906 width of the commands listed in the 'help' command output.
2908 - CONFIG_SYS_PROMPT: This is what U-Boot prints on the console to
2909 prompt for user input.
2911 - CONFIG_SYS_CBSIZE: Buffer size for input from the Console
2913 - CONFIG_SYS_PBSIZE: Buffer size for Console output
2915 - CONFIG_SYS_MAXARGS: max. Number of arguments accepted for monitor commands
2917 - CONFIG_SYS_BARGSIZE: Buffer size for Boot Arguments which are passed to
2918 the application (usually a Linux kernel) when it is
2921 - CONFIG_SYS_BAUDRATE_TABLE:
2922 List of legal baudrate settings for this board.
2924 - CONFIG_SYS_CONSOLE_INFO_QUIET
2925 Suppress display of console information at boot.
2927 - CONFIG_SYS_CONSOLE_IS_IN_ENV
2928 If the board specific function
2929 extern int overwrite_console (void);
2930 returns 1, the stdin, stderr and stdout are switched to the
2931 serial port, else the settings in the environment are used.
2933 - CONFIG_SYS_CONSOLE_OVERWRITE_ROUTINE
2934 Enable the call to overwrite_console().
2936 - CONFIG_SYS_CONSOLE_ENV_OVERWRITE
2937 Enable overwrite of previous console environment settings.
2939 - CONFIG_SYS_MEMTEST_START, CONFIG_SYS_MEMTEST_END:
2940 Begin and End addresses of the area used by the
2943 - CONFIG_SYS_ALT_MEMTEST:
2944 Enable an alternate, more extensive memory test.
2946 - CONFIG_SYS_MEMTEST_SCRATCH:
2947 Scratch address used by the alternate memory test
2948 You only need to set this if address zero isn't writeable
2950 - CONFIG_SYS_MEM_TOP_HIDE (PPC only):
2951 If CONFIG_SYS_MEM_TOP_HIDE is defined in the board config header,
2952 this specified memory area will get subtracted from the top
2953 (end) of RAM and won't get "touched" at all by U-Boot. By
2954 fixing up gd->ram_size the Linux kernel should gets passed
2955 the now "corrected" memory size and won't touch it either.
2956 This should work for arch/ppc and arch/powerpc. Only Linux
2957 board ports in arch/powerpc with bootwrapper support that
2958 recalculate the memory size from the SDRAM controller setup
2959 will have to get fixed in Linux additionally.
2961 This option can be used as a workaround for the 440EPx/GRx
2962 CHIP 11 errata where the last 256 bytes in SDRAM shouldn't
2965 WARNING: Please make sure that this value is a multiple of
2966 the Linux page size (normally 4k). If this is not the case,
2967 then the end address of the Linux memory will be located at a
2968 non page size aligned address and this could cause major
2971 - CONFIG_SYS_TFTP_LOADADDR:
2972 Default load address for network file downloads
2974 - CONFIG_SYS_LOADS_BAUD_CHANGE:
2975 Enable temporary baudrate change while serial download
2977 - CONFIG_SYS_SDRAM_BASE:
2978 Physical start address of SDRAM. _Must_ be 0 here.
2980 - CONFIG_SYS_MBIO_BASE:
2981 Physical start address of Motherboard I/O (if using a
2984 - CONFIG_SYS_FLASH_BASE:
2985 Physical start address of Flash memory.
2987 - CONFIG_SYS_MONITOR_BASE:
2988 Physical start address of boot monitor code (set by
2989 make config files to be same as the text base address
2990 (CONFIG_SYS_TEXT_BASE) used when linking) - same as
2991 CONFIG_SYS_FLASH_BASE when booting from flash.
2993 - CONFIG_SYS_MONITOR_LEN:
2994 Size of memory reserved for monitor code, used to
2995 determine _at_compile_time_ (!) if the environment is
2996 embedded within the U-Boot image, or in a separate
2999 - CONFIG_SYS_MALLOC_LEN:
3000 Size of DRAM reserved for malloc() use.
3002 - CONFIG_SYS_BOOTM_LEN:
3003 Normally compressed uImages are limited to an
3004 uncompressed size of 8 MBytes. If this is not enough,
3005 you can define CONFIG_SYS_BOOTM_LEN in your board config file
3006 to adjust this setting to your needs.
3008 - CONFIG_SYS_BOOTMAPSZ:
3009 Maximum size of memory mapped by the startup code of
3010 the Linux kernel; all data that must be processed by
3011 the Linux kernel (bd_info, boot arguments, FDT blob if
3012 used) must be put below this limit, unless "bootm_low"
3013 enviroment variable is defined and non-zero. In such case
3014 all data for the Linux kernel must be between "bootm_low"
3015 and "bootm_low" + CONFIG_SYS_BOOTMAPSZ. The environment
3016 variable "bootm_mapsize" will override the value of
3017 CONFIG_SYS_BOOTMAPSZ. If CONFIG_SYS_BOOTMAPSZ is undefined,
3018 then the value in "bootm_size" will be used instead.
3020 - CONFIG_SYS_BOOT_RAMDISK_HIGH:
3021 Enable initrd_high functionality. If defined then the
3022 initrd_high feature is enabled and the bootm ramdisk subcommand
3025 - CONFIG_SYS_BOOT_GET_CMDLINE:
3026 Enables allocating and saving kernel cmdline in space between
3027 "bootm_low" and "bootm_low" + BOOTMAPSZ.
3029 - CONFIG_SYS_BOOT_GET_KBD:
3030 Enables allocating and saving a kernel copy of the bd_info in
3031 space between "bootm_low" and "bootm_low" + BOOTMAPSZ.
3033 - CONFIG_SYS_MAX_FLASH_BANKS:
3034 Max number of Flash memory banks
3036 - CONFIG_SYS_MAX_FLASH_SECT:
3037 Max number of sectors on a Flash chip
3039 - CONFIG_SYS_FLASH_ERASE_TOUT:
3040 Timeout for Flash erase operations (in ms)
3042 - CONFIG_SYS_FLASH_WRITE_TOUT:
3043 Timeout for Flash write operations (in ms)
3045 - CONFIG_SYS_FLASH_LOCK_TOUT
3046 Timeout for Flash set sector lock bit operation (in ms)
3048 - CONFIG_SYS_FLASH_UNLOCK_TOUT
3049 Timeout for Flash clear lock bits operation (in ms)
3051 - CONFIG_SYS_FLASH_PROTECTION
3052 If defined, hardware flash sectors protection is used
3053 instead of U-Boot software protection.
3055 - CONFIG_SYS_DIRECT_FLASH_TFTP:
3057 Enable TFTP transfers directly to flash memory;
3058 without this option such a download has to be
3059 performed in two steps: (1) download to RAM, and (2)
3060 copy from RAM to flash.
3062 The two-step approach is usually more reliable, since
3063 you can check if the download worked before you erase
3064 the flash, but in some situations (when system RAM is
3065 too limited to allow for a temporary copy of the
3066 downloaded image) this option may be very useful.
3068 - CONFIG_SYS_FLASH_CFI:
3069 Define if the flash driver uses extra elements in the
3070 common flash structure for storing flash geometry.
3072 - CONFIG_FLASH_CFI_DRIVER
3073 This option also enables the building of the cfi_flash driver
3074 in the drivers directory
3076 - CONFIG_FLASH_CFI_MTD
3077 This option enables the building of the cfi_mtd driver
3078 in the drivers directory. The driver exports CFI flash
3081 - CONFIG_SYS_FLASH_USE_BUFFER_WRITE
3082 Use buffered writes to flash.
3084 - CONFIG_FLASH_SPANSION_S29WS_N
3085 s29ws-n MirrorBit flash has non-standard addresses for buffered
3088 - CONFIG_SYS_FLASH_QUIET_TEST
3089 If this option is defined, the common CFI flash doesn't
3090 print it's warning upon not recognized FLASH banks. This
3091 is useful, if some of the configured banks are only
3092 optionally available.
3094 - CONFIG_FLASH_SHOW_PROGRESS
3095 If defined (must be an integer), print out countdown
3096 digits and dots. Recommended value: 45 (9..1) for 80
3097 column displays, 15 (3..1) for 40 column displays.
3099 - CONFIG_SYS_RX_ETH_BUFFER:
3100 Defines the number of Ethernet receive buffers. On some
3101 Ethernet controllers it is recommended to set this value
3102 to 8 or even higher (EEPRO100 or 405 EMAC), since all
3103 buffers can be full shortly after enabling the interface
3104 on high Ethernet traffic.
3105 Defaults to 4 if not defined.
3107 - CONFIG_ENV_MAX_ENTRIES
3109 Maximum number of entries in the hash table that is used
3110 internally to store the environment settings. The default
3111 setting is supposed to be generous and should work in most
3112 cases. This setting can be used to tune behaviour; see
3113 lib/hashtable.c for details.
3115 The following definitions that deal with the placement and management
3116 of environment data (variable area); in general, we support the
3117 following configurations:
3119 - CONFIG_BUILD_ENVCRC:
3121 Builds up envcrc with the target environment so that external utils
3122 may easily extract it and embed it in final U-Boot images.
3124 - CONFIG_ENV_IS_IN_FLASH:
3126 Define this if the environment is in flash memory.
3128 a) The environment occupies one whole flash sector, which is
3129 "embedded" in the text segment with the U-Boot code. This
3130 happens usually with "bottom boot sector" or "top boot
3131 sector" type flash chips, which have several smaller
3132 sectors at the start or the end. For instance, such a
3133 layout can have sector sizes of 8, 2x4, 16, Nx32 kB. In
3134 such a case you would place the environment in one of the
3135 4 kB sectors - with U-Boot code before and after it. With
3136 "top boot sector" type flash chips, you would put the
3137 environment in one of the last sectors, leaving a gap
3138 between U-Boot and the environment.
3140 - CONFIG_ENV_OFFSET:
3142 Offset of environment data (variable area) to the
3143 beginning of flash memory; for instance, with bottom boot
3144 type flash chips the second sector can be used: the offset
3145 for this sector is given here.
3147 CONFIG_ENV_OFFSET is used relative to CONFIG_SYS_FLASH_BASE.
3151 This is just another way to specify the start address of
3152 the flash sector containing the environment (instead of
3155 - CONFIG_ENV_SECT_SIZE:
3157 Size of the sector containing the environment.
3160 b) Sometimes flash chips have few, equal sized, BIG sectors.
3161 In such a case you don't want to spend a whole sector for
3166 If you use this in combination with CONFIG_ENV_IS_IN_FLASH
3167 and CONFIG_ENV_SECT_SIZE, you can specify to use only a part
3168 of this flash sector for the environment. This saves
3169 memory for the RAM copy of the environment.
3171 It may also save flash memory if you decide to use this
3172 when your environment is "embedded" within U-Boot code,
3173 since then the remainder of the flash sector could be used
3174 for U-Boot code. It should be pointed out that this is
3175 STRONGLY DISCOURAGED from a robustness point of view:
3176 updating the environment in flash makes it always
3177 necessary to erase the WHOLE sector. If something goes
3178 wrong before the contents has been restored from a copy in
3179 RAM, your target system will be dead.
3181 - CONFIG_ENV_ADDR_REDUND
3182 CONFIG_ENV_SIZE_REDUND
3184 These settings describe a second storage area used to hold
3185 a redundant copy of the environment data, so that there is
3186 a valid backup copy in case there is a power failure during
3187 a "saveenv" operation.
3189 BE CAREFUL! Any changes to the flash layout, and some changes to the
3190 source code will make it necessary to adapt <board>/u-boot.lds*
3194 - CONFIG_ENV_IS_IN_NVRAM:
3196 Define this if you have some non-volatile memory device
3197 (NVRAM, battery buffered SRAM) which you want to use for the
3203 These two #defines are used to determine the memory area you
3204 want to use for environment. It is assumed that this memory
3205 can just be read and written to, without any special
3208 BE CAREFUL! The first access to the environment happens quite early
3209 in U-Boot initalization (when we try to get the setting of for the
3210 console baudrate). You *MUST* have mapped your NVRAM area then, or
3213 Please note that even with NVRAM we still use a copy of the
3214 environment in RAM: we could work on NVRAM directly, but we want to
3215 keep settings there always unmodified except somebody uses "saveenv"
3216 to save the current settings.
3219 - CONFIG_ENV_IS_IN_EEPROM:
3221 Use this if you have an EEPROM or similar serial access
3222 device and a driver for it.
3224 - CONFIG_ENV_OFFSET:
3227 These two #defines specify the offset and size of the
3228 environment area within the total memory of your EEPROM.
3230 - CONFIG_SYS_I2C_EEPROM_ADDR:
3231 If defined, specified the chip address of the EEPROM device.
3232 The default address is zero.
3234 - CONFIG_SYS_EEPROM_PAGE_WRITE_BITS:
3235 If defined, the number of bits used to address bytes in a
3236 single page in the EEPROM device. A 64 byte page, for example
3237 would require six bits.
3239 - CONFIG_SYS_EEPROM_PAGE_WRITE_DELAY_MS:
3240 If defined, the number of milliseconds to delay between
3241 page writes. The default is zero milliseconds.
3243 - CONFIG_SYS_I2C_EEPROM_ADDR_LEN:
3244 The length in bytes of the EEPROM memory array address. Note
3245 that this is NOT the chip address length!
3247 - CONFIG_SYS_I2C_EEPROM_ADDR_OVERFLOW:
3248 EEPROM chips that implement "address overflow" are ones
3249 like Catalyst 24WC04/08/16 which has 9/10/11 bits of
3250 address and the extra bits end up in the "chip address" bit
3251 slots. This makes a 24WC08 (1Kbyte) chip look like four 256
3254 Note that we consider the length of the address field to
3255 still be one byte because the extra address bits are hidden
3256 in the chip address.
3258 - CONFIG_SYS_EEPROM_SIZE:
3259 The size in bytes of the EEPROM device.
3261 - CONFIG_ENV_EEPROM_IS_ON_I2C
3262 define this, if you have I2C and SPI activated, and your
3263 EEPROM, which holds the environment, is on the I2C bus.
3265 - CONFIG_I2C_ENV_EEPROM_BUS
3266 if you have an Environment on an EEPROM reached over
3267 I2C muxes, you can define here, how to reach this
3268 EEPROM. For example:
3270 #define CONFIG_I2C_ENV_EEPROM_BUS "pca9547:70:d\0"
3272 EEPROM which holds the environment, is reached over
3273 a pca9547 i2c mux with address 0x70, channel 3.
3275 - CONFIG_ENV_IS_IN_DATAFLASH:
3277 Define this if you have a DataFlash memory device which you
3278 want to use for the environment.
3280 - CONFIG_ENV_OFFSET:
3284 These three #defines specify the offset and size of the
3285 environment area within the total memory of your DataFlash placed
3286 at the specified address.
3288 - CONFIG_ENV_IS_IN_REMOTE:
3290 Define this if you have a remote memory space which you
3291 want to use for the local device's environment.
3296 These two #defines specify the address and size of the
3297 environment area within the remote memory space. The
3298 local device can get the environment from remote memory
3299 space by SRIO or PCIE links.
3301 BE CAREFUL! For some special cases, the local device can not use
3302 "saveenv" command. For example, the local device will get the
3303 environment stored in a remote NOR flash by SRIO or PCIE link,
3304 but it can not erase, write this NOR flash by SRIO or PCIE interface.
3306 - CONFIG_ENV_IS_IN_NAND:
3308 Define this if you have a NAND device which you want to use
3309 for the environment.
3311 - CONFIG_ENV_OFFSET:
3314 These two #defines specify the offset and size of the environment
3315 area within the first NAND device. CONFIG_ENV_OFFSET must be
3316 aligned to an erase block boundary.
3318 - CONFIG_ENV_OFFSET_REDUND (optional):
3320 This setting describes a second storage area of CONFIG_ENV_SIZE
3321 size used to hold a redundant copy of the environment data, so
3322 that there is a valid backup copy in case there is a power failure
3323 during a "saveenv" operation. CONFIG_ENV_OFFSET_RENDUND must be
3324 aligned to an erase block boundary.
3326 - CONFIG_ENV_RANGE (optional):
3328 Specifies the length of the region in which the environment
3329 can be written. This should be a multiple of the NAND device's
3330 block size. Specifying a range with more erase blocks than
3331 are needed to hold CONFIG_ENV_SIZE allows bad blocks within
3332 the range to be avoided.
3334 - CONFIG_ENV_OFFSET_OOB (optional):
3336 Enables support for dynamically retrieving the offset of the
3337 environment from block zero's out-of-band data. The
3338 "nand env.oob" command can be used to record this offset.
3339 Currently, CONFIG_ENV_OFFSET_REDUND is not supported when
3340 using CONFIG_ENV_OFFSET_OOB.
3342 - CONFIG_NAND_ENV_DST
3344 Defines address in RAM to which the nand_spl code should copy the
3345 environment. If redundant environment is used, it will be copied to
3346 CONFIG_NAND_ENV_DST + CONFIG_ENV_SIZE.
3348 - CONFIG_SYS_SPI_INIT_OFFSET
3350 Defines offset to the initial SPI buffer area in DPRAM. The
3351 area is used at an early stage (ROM part) if the environment
3352 is configured to reside in the SPI EEPROM: We need a 520 byte
3353 scratch DPRAM area. It is used between the two initialization
3354 calls (spi_init_f() and spi_init_r()). A value of 0xB00 seems
3355 to be a good choice since it makes it far enough from the
3356 start of the data area as well as from the stack pointer.
3358 Please note that the environment is read-only until the monitor
3359 has been relocated to RAM and a RAM copy of the environment has been
3360 created; also, when using EEPROM you will have to use getenv_f()
3361 until then to read environment variables.
3363 The environment is protected by a CRC32 checksum. Before the monitor
3364 is relocated into RAM, as a result of a bad CRC you will be working
3365 with the compiled-in default environment - *silently*!!! [This is
3366 necessary, because the first environment variable we need is the
3367 "baudrate" setting for the console - if we have a bad CRC, we don't
3368 have any device yet where we could complain.]
3370 Note: once the monitor has been relocated, then it will complain if
3371 the default environment is used; a new CRC is computed as soon as you
3372 use the "saveenv" command to store a valid environment.
3374 - CONFIG_SYS_FAULT_ECHO_LINK_DOWN:
3375 Echo the inverted Ethernet link state to the fault LED.
3377 Note: If this option is active, then CONFIG_SYS_FAULT_MII_ADDR
3378 also needs to be defined.
3380 - CONFIG_SYS_FAULT_MII_ADDR:
3381 MII address of the PHY to check for the Ethernet link state.
3383 - CONFIG_NS16550_MIN_FUNCTIONS:
3384 Define this if you desire to only have use of the NS16550_init
3385 and NS16550_putc functions for the serial driver located at
3386 drivers/serial/ns16550.c. This option is useful for saving
3387 space for already greatly restricted images, including but not
3388 limited to NAND_SPL configurations.
3390 Low Level (hardware related) configuration options:
3391 ---------------------------------------------------
3393 - CONFIG_SYS_CACHELINE_SIZE:
3394 Cache Line Size of the CPU.
3396 - CONFIG_SYS_DEFAULT_IMMR:
3397 Default address of the IMMR after system reset.
3399 Needed on some 8260 systems (MPC8260ADS, PQ2FADS-ZU,
3400 and RPXsuper) to be able to adjust the position of
3401 the IMMR register after a reset.
3403 - CONFIG_SYS_CCSRBAR_DEFAULT:
3404 Default (power-on reset) physical address of CCSR on Freescale
3407 - CONFIG_SYS_CCSRBAR:
3408 Virtual address of CCSR. On a 32-bit build, this is typically
3409 the same value as CONFIG_SYS_CCSRBAR_DEFAULT.
3411 CONFIG_SYS_DEFAULT_IMMR must also be set to this value,
3412 for cross-platform code that uses that macro instead.
3414 - CONFIG_SYS_CCSRBAR_PHYS:
3415 Physical address of CCSR. CCSR can be relocated to a new
3416 physical address, if desired. In this case, this macro should
3417 be set to that address. Otherwise, it should be set to the
3418 same value as CONFIG_SYS_CCSRBAR_DEFAULT. For example, CCSR
3419 is typically relocated on 36-bit builds. It is recommended
3420 that this macro be defined via the _HIGH and _LOW macros:
3422 #define CONFIG_SYS_CCSRBAR_PHYS ((CONFIG_SYS_CCSRBAR_PHYS_HIGH
3423 * 1ull) << 32 | CONFIG_SYS_CCSRBAR_PHYS_LOW)
3425 - CONFIG_SYS_CCSRBAR_PHYS_HIGH:
3426 Bits 33-36 of CONFIG_SYS_CCSRBAR_PHYS. This value is typically
3427 either 0 (32-bit build) or 0xF (36-bit build). This macro is
3428 used in assembly code, so it must not contain typecasts or
3429 integer size suffixes (e.g. "ULL").
3431 - CONFIG_SYS_CCSRBAR_PHYS_LOW:
3432 Lower 32-bits of CONFIG_SYS_CCSRBAR_PHYS. This macro is
3433 used in assembly code, so it must not contain typecasts or
3434 integer size suffixes (e.g. "ULL").
3436 - CONFIG_SYS_CCSR_DO_NOT_RELOCATE:
3437 If this macro is defined, then CONFIG_SYS_CCSRBAR_PHYS will be
3438 forced to a value that ensures that CCSR is not relocated.
3440 - Floppy Disk Support:
3441 CONFIG_SYS_FDC_DRIVE_NUMBER
3443 the default drive number (default value 0)
3445 CONFIG_SYS_ISA_IO_STRIDE
3447 defines the spacing between FDC chipset registers
3450 CONFIG_SYS_ISA_IO_OFFSET
3452 defines the offset of register from address. It
3453 depends on which part of the data bus is connected to
3454 the FDC chipset. (default value 0)
3456 If CONFIG_SYS_ISA_IO_STRIDE CONFIG_SYS_ISA_IO_OFFSET and
3457 CONFIG_SYS_FDC_DRIVE_NUMBER are undefined, they take their
3460 if CONFIG_SYS_FDC_HW_INIT is defined, then the function
3461 fdc_hw_init() is called at the beginning of the FDC
3462 setup. fdc_hw_init() must be provided by the board
3463 source code. It is used to make hardware dependant
3467 Most IDE controllers were designed to be connected with PCI
3468 interface. Only few of them were designed for AHB interface.
3469 When software is doing ATA command and data transfer to
3470 IDE devices through IDE-AHB controller, some additional
3471 registers accessing to these kind of IDE-AHB controller
3474 - CONFIG_SYS_IMMR: Physical address of the Internal Memory.
3475 DO NOT CHANGE unless you know exactly what you're
3476 doing! (11-4) [MPC8xx/82xx systems only]
3478 - CONFIG_SYS_INIT_RAM_ADDR:
3480 Start address of memory area that can be used for
3481 initial data and stack; please note that this must be
3482 writable memory that is working WITHOUT special
3483 initialization, i. e. you CANNOT use normal RAM which
3484 will become available only after programming the
3485 memory controller and running certain initialization
3488 U-Boot uses the following memory types:
3489 - MPC8xx and MPC8260: IMMR (internal memory of the CPU)
3490 - MPC824X: data cache
3491 - PPC4xx: data cache
3493 - CONFIG_SYS_GBL_DATA_OFFSET:
3495 Offset of the initial data structure in the memory
3496 area defined by CONFIG_SYS_INIT_RAM_ADDR. Usually
3497 CONFIG_SYS_GBL_DATA_OFFSET is chosen such that the initial
3498 data is located at the end of the available space
3499 (sometimes written as (CONFIG_SYS_INIT_RAM_SIZE -
3500 CONFIG_SYS_INIT_DATA_SIZE), and the initial stack is just
3501 below that area (growing from (CONFIG_SYS_INIT_RAM_ADDR +
3502 CONFIG_SYS_GBL_DATA_OFFSET) downward.
3505 On the MPC824X (or other systems that use the data
3506 cache for initial memory) the address chosen for
3507 CONFIG_SYS_INIT_RAM_ADDR is basically arbitrary - it must
3508 point to an otherwise UNUSED address space between
3509 the top of RAM and the start of the PCI space.
3511 - CONFIG_SYS_SIUMCR: SIU Module Configuration (11-6)
3513 - CONFIG_SYS_SYPCR: System Protection Control (11-9)
3515 - CONFIG_SYS_TBSCR: Time Base Status and Control (11-26)
3517 - CONFIG_SYS_PISCR: Periodic Interrupt Status and Control (11-31)
3519 - CONFIG_SYS_PLPRCR: PLL, Low-Power, and Reset Control Register (15-30)
3521 - CONFIG_SYS_SCCR: System Clock and reset Control Register (15-27)
3523 - CONFIG_SYS_OR_TIMING_SDRAM:
3526 - CONFIG_SYS_MAMR_PTA:
3527 periodic timer for refresh
3529 - CONFIG_SYS_DER: Debug Event Register (37-47)
3531 - FLASH_BASE0_PRELIM, FLASH_BASE1_PRELIM, CONFIG_SYS_REMAP_OR_AM,
3532 CONFIG_SYS_PRELIM_OR_AM, CONFIG_SYS_OR_TIMING_FLASH, CONFIG_SYS_OR0_REMAP,
3533 CONFIG_SYS_OR0_PRELIM, CONFIG_SYS_BR0_PRELIM, CONFIG_SYS_OR1_REMAP, CONFIG_SYS_OR1_PRELIM,
3534 CONFIG_SYS_BR1_PRELIM:
3535 Memory Controller Definitions: BR0/1 and OR0/1 (FLASH)
3537 - SDRAM_BASE2_PRELIM, SDRAM_BASE3_PRELIM, SDRAM_MAX_SIZE,
3538 CONFIG_SYS_OR_TIMING_SDRAM, CONFIG_SYS_OR2_PRELIM, CONFIG_SYS_BR2_PRELIM,
3539 CONFIG_SYS_OR3_PRELIM, CONFIG_SYS_BR3_PRELIM:
3540 Memory Controller Definitions: BR2/3 and OR2/3 (SDRAM)
3542 - CONFIG_SYS_MAMR_PTA, CONFIG_SYS_MPTPR_2BK_4K, CONFIG_SYS_MPTPR_1BK_4K, CONFIG_SYS_MPTPR_2BK_8K,
3543 CONFIG_SYS_MPTPR_1BK_8K, CONFIG_SYS_MAMR_8COL, CONFIG_SYS_MAMR_9COL:
3544 Machine Mode Register and Memory Periodic Timer
3545 Prescaler definitions (SDRAM timing)
3547 - CONFIG_SYS_I2C_UCODE_PATCH, CONFIG_SYS_I2C_DPMEM_OFFSET [0x1FC0]:
3548 enable I2C microcode relocation patch (MPC8xx);
3549 define relocation offset in DPRAM [DSP2]
3551 - CONFIG_SYS_SMC_UCODE_PATCH, CONFIG_SYS_SMC_DPMEM_OFFSET [0x1FC0]:
3552 enable SMC microcode relocation patch (MPC8xx);
3553 define relocation offset in DPRAM [SMC1]
3555 - CONFIG_SYS_SPI_UCODE_PATCH, CONFIG_SYS_SPI_DPMEM_OFFSET [0x1FC0]:
3556 enable SPI microcode relocation patch (MPC8xx);
3557 define relocation offset in DPRAM [SCC4]
3559 - CONFIG_SYS_USE_OSCCLK:
3560 Use OSCM clock mode on MBX8xx board. Be careful,
3561 wrong setting might damage your board. Read
3562 doc/README.MBX before setting this variable!
3564 - CONFIG_SYS_CPM_POST_WORD_ADDR: (MPC8xx, MPC8260 only)
3565 Offset of the bootmode word in DPRAM used by post
3566 (Power On Self Tests). This definition overrides
3567 #define'd default value in commproc.h resp.
3570 - CONFIG_SYS_PCI_SLV_MEM_LOCAL, CONFIG_SYS_PCI_SLV_MEM_BUS, CONFIG_SYS_PICMR0_MASK_ATTRIB,
3571 CONFIG_SYS_PCI_MSTR0_LOCAL, CONFIG_SYS_PCIMSK0_MASK, CONFIG_SYS_PCI_MSTR1_LOCAL,
3572 CONFIG_SYS_PCIMSK1_MASK, CONFIG_SYS_PCI_MSTR_MEM_LOCAL, CONFIG_SYS_PCI_MSTR_MEM_BUS,
3573 CONFIG_SYS_CPU_PCI_MEM_START, CONFIG_SYS_PCI_MSTR_MEM_SIZE, CONFIG_SYS_POCMR0_MASK_ATTRIB,
3574 CONFIG_SYS_PCI_MSTR_MEMIO_LOCAL, CONFIG_SYS_PCI_MSTR_MEMIO_BUS, CPU_PCI_MEMIO_START,
3575 CONFIG_SYS_PCI_MSTR_MEMIO_SIZE, CONFIG_SYS_POCMR1_MASK_ATTRIB, CONFIG_SYS_PCI_MSTR_IO_LOCAL,
3576 CONFIG_SYS_PCI_MSTR_IO_BUS, CONFIG_SYS_CPU_PCI_IO_START, CONFIG_SYS_PCI_MSTR_IO_SIZE,
3577 CONFIG_SYS_POCMR2_MASK_ATTRIB: (MPC826x only)
3578 Overrides the default PCI memory map in arch/powerpc/cpu/mpc8260/pci.c if set.
3580 - CONFIG_PCI_DISABLE_PCIE:
3581 Disable PCI-Express on systems where it is supported but not
3584 - CONFIG_PCI_ENUM_ONLY
3585 Only scan through and get the devices on the busses.
3586 Don't do any setup work, presumably because someone or
3587 something has already done it, and we don't need to do it
3588 a second time. Useful for platforms that are pre-booted
3589 by coreboot or similar.
3592 Chip has SRIO or not
3595 Board has SRIO 1 port available
3598 Board has SRIO 2 port available
3600 - CONFIG_SYS_SRIOn_MEM_VIRT:
3601 Virtual Address of SRIO port 'n' memory region
3603 - CONFIG_SYS_SRIOn_MEM_PHYS:
3604 Physical Address of SRIO port 'n' memory region
3606 - CONFIG_SYS_SRIOn_MEM_SIZE:
3607 Size of SRIO port 'n' memory region
3609 - CONFIG_SYS_NDFC_16
3610 Defined to tell the NDFC that the NAND chip is using a
3613 - CONFIG_SYS_NDFC_EBC0_CFG
3614 Sets the EBC0_CFG register for the NDFC. If not defined
3615 a default value will be used.
3618 Get DDR timing information from an I2C EEPROM. Common
3619 with pluggable memory modules such as SODIMMs
3622 I2C address of the SPD EEPROM
3624 - CONFIG_SYS_SPD_BUS_NUM
3625 If SPD EEPROM is on an I2C bus other than the first
3626 one, specify here. Note that the value must resolve
3627 to something your driver can deal with.
3629 - CONFIG_SYS_DDR_RAW_TIMING
3630 Get DDR timing information from other than SPD. Common with
3631 soldered DDR chips onboard without SPD. DDR raw timing
3632 parameters are extracted from datasheet and hard-coded into
3633 header files or board specific files.
3635 - CONFIG_FSL_DDR_INTERACTIVE
3636 Enable interactive DDR debugging. See doc/README.fsl-ddr.
3638 - CONFIG_SYS_83XX_DDR_USES_CS0
3639 Only for 83xx systems. If specified, then DDR should
3640 be configured using CS0 and CS1 instead of CS2 and CS3.
3642 - CONFIG_ETHER_ON_FEC[12]
3643 Define to enable FEC[12] on a 8xx series processor.
3645 - CONFIG_FEC[12]_PHY
3646 Define to the hardcoded PHY address which corresponds
3647 to the given FEC; i. e.
3648 #define CONFIG_FEC1_PHY 4
3649 means that the PHY with address 4 is connected to FEC1
3651 When set to -1, means to probe for first available.
3653 - CONFIG_FEC[12]_PHY_NORXERR
3654 The PHY does not have a RXERR line (RMII only).
3655 (so program the FEC to ignore it).
3658 Enable RMII mode for all FECs.
3659 Note that this is a global option, we can't
3660 have one FEC in standard MII mode and another in RMII mode.
3662 - CONFIG_CRC32_VERIFY
3663 Add a verify option to the crc32 command.
3666 => crc32 -v <address> <count> <crc32>
3668 Where address/count indicate a memory area
3669 and crc32 is the correct crc32 which the
3673 Add the "loopw" memory command. This only takes effect if
3674 the memory commands are activated globally (CONFIG_CMD_MEM).
3677 Add the "mdc" and "mwc" memory commands. These are cyclic
3682 This command will print 4 bytes (10,11,12,13) each 500 ms.
3684 => mwc.l 100 12345678 10
3685 This command will write 12345678 to address 100 all 10 ms.
3687 This only takes effect if the memory commands are activated
3688 globally (CONFIG_CMD_MEM).
3690 - CONFIG_SKIP_LOWLEVEL_INIT
3691 [ARM, NDS32, MIPS only] If this variable is defined, then certain
3692 low level initializations (like setting up the memory
3693 controller) are omitted and/or U-Boot does not
3694 relocate itself into RAM.
3696 Normally this variable MUST NOT be defined. The only
3697 exception is when U-Boot is loaded (to RAM) by some
3698 other boot loader or by a debugger which performs
3699 these initializations itself.
3702 Modifies the behaviour of start.S when compiling a loader
3703 that is executed before the actual U-Boot. E.g. when
3704 compiling a NAND SPL.
3706 - CONFIG_USE_ARCH_MEMCPY
3707 CONFIG_USE_ARCH_MEMSET
3708 If these options are used a optimized version of memcpy/memset will
3709 be used if available. These functions may be faster under some
3710 conditions but may increase the binary size.
3712 - CONFIG_X86_NO_RESET_VECTOR
3713 If defined, the x86 reset vector code is excluded. You will need
3714 to do this when U-Boot is running from Coreboot.
3716 - CONFIG_X86_NO_REAL_MODE
3717 If defined, x86 real mode code is omitted. This assumes a
3718 32-bit environment where such code is not needed. You will
3719 need to do this when U-Boot is running from Coreboot.
3722 Freescale QE/FMAN Firmware Support:
3723 -----------------------------------
3725 The Freescale QUICCEngine (QE) and Frame Manager (FMAN) both support the
3726 loading of "firmware", which is encoded in the QE firmware binary format.
3727 This firmware often needs to be loaded during U-Boot booting, so macros
3728 are used to identify the storage device (NOR flash, SPI, etc) and the address
3731 - CONFIG_SYS_QE_FMAN_FW_ADDR
3732 The address in the storage device where the firmware is located. The
3733 meaning of this address depends on which CONFIG_SYS_QE_FW_IN_xxx macro
3736 - CONFIG_SYS_QE_FMAN_FW_LENGTH
3737 The maximum possible size of the firmware. The firmware binary format
3738 has a field that specifies the actual size of the firmware, but it
3739 might not be possible to read any part of the firmware unless some
3740 local storage is allocated to hold the entire firmware first.
3742 - CONFIG_SYS_QE_FMAN_FW_IN_NOR
3743 Specifies that QE/FMAN firmware is located in NOR flash, mapped as
3744 normal addressable memory via the LBC. CONFIG_SYS_FMAN_FW_ADDR is the
3745 virtual address in NOR flash.
3747 - CONFIG_SYS_QE_FMAN_FW_IN_NAND
3748 Specifies that QE/FMAN firmware is located in NAND flash.
3749 CONFIG_SYS_FMAN_FW_ADDR is the offset within NAND flash.
3751 - CONFIG_SYS_QE_FMAN_FW_IN_MMC
3752 Specifies that QE/FMAN firmware is located on the primary SD/MMC
3753 device. CONFIG_SYS_FMAN_FW_ADDR is the byte offset on that device.
3755 - CONFIG_SYS_QE_FMAN_FW_IN_SPIFLASH
3756 Specifies that QE/FMAN firmware is located on the primary SPI
3757 device. CONFIG_SYS_FMAN_FW_ADDR is the byte offset on that device.
3759 - CONFIG_SYS_QE_FMAN_FW_IN_REMOTE
3760 Specifies that QE/FMAN firmware is located in the remote (master)
3761 memory space. CONFIG_SYS_FMAN_FW_ADDR is a virtual address which
3762 can be mapped from slave TLB->slave LAW->slave SRIO or PCIE outbound
3763 window->master inbound window->master LAW->the ucode address in
3764 master's memory space.
3766 Building the Software:
3767 ======================
3769 Building U-Boot has been tested in several native build environments
3770 and in many different cross environments. Of course we cannot support
3771 all possibly existing versions of cross development tools in all
3772 (potentially obsolete) versions. In case of tool chain problems we
3773 recommend to use the ELDK (see http://www.denx.de/wiki/DULG/ELDK)
3774 which is extensively used to build and test U-Boot.
3776 If you are not using a native environment, it is assumed that you
3777 have GNU cross compiling tools available in your path. In this case,
3778 you must set the environment variable CROSS_COMPILE in your shell.
3779 Note that no changes to the Makefile or any other source files are
3780 necessary. For example using the ELDK on a 4xx CPU, please enter:
3782 $ CROSS_COMPILE=ppc_4xx-
3783 $ export CROSS_COMPILE
3785 Note: If you wish to generate Windows versions of the utilities in
3786 the tools directory you can use the MinGW toolchain
3787 (http://www.mingw.org). Set your HOST tools to the MinGW
3788 toolchain and execute 'make tools'. For example:
3790 $ make HOSTCC=i586-mingw32msvc-gcc HOSTSTRIP=i586-mingw32msvc-strip tools
3792 Binaries such as tools/mkimage.exe will be created which can
3793 be executed on computers running Windows.
3795 U-Boot is intended to be simple to build. After installing the
3796 sources you must configure U-Boot for one specific board type. This
3801 where "NAME_config" is the name of one of the existing configu-
3802 rations; see boards.cfg for supported names.
3804 Note: for some board special configuration names may exist; check if
3805 additional information is available from the board vendor; for
3806 instance, the TQM823L systems are available without (standard)
3807 or with LCD support. You can select such additional "features"
3808 when choosing the configuration, i. e.
3811 - will configure for a plain TQM823L, i. e. no LCD support
3813 make TQM823L_LCD_config
3814 - will configure for a TQM823L with U-Boot console on LCD
3819 Finally, type "make all", and you should get some working U-Boot
3820 images ready for download to / installation on your system:
3822 - "u-boot.bin" is a raw binary image
3823 - "u-boot" is an image in ELF binary format
3824 - "u-boot.srec" is in Motorola S-Record format
3826 By default the build is performed locally and the objects are saved
3827 in the source directory. One of the two methods can be used to change
3828 this behavior and build U-Boot to some external directory:
3830 1. Add O= to the make command line invocations:
3832 make O=/tmp/build distclean
3833 make O=/tmp/build NAME_config
3834 make O=/tmp/build all
3836 2. Set environment variable BUILD_DIR to point to the desired location:
3838 export BUILD_DIR=/tmp/build
3843 Note that the command line "O=" setting overrides the BUILD_DIR environment
3847 Please be aware that the Makefiles assume you are using GNU make, so
3848 for instance on NetBSD you might need to use "gmake" instead of
3852 If the system board that you have is not listed, then you will need
3853 to port U-Boot to your hardware platform. To do this, follow these
3856 1. Add a new configuration option for your board to the toplevel
3857 "boards.cfg" file, using the existing entries as examples.
3858 Follow the instructions there to keep the boards in order.
3859 2. Create a new directory to hold your board specific code. Add any
3860 files you need. In your board directory, you will need at least
3861 the "Makefile", a "<board>.c", "flash.c" and "u-boot.lds".
3862 3. Create a new configuration file "include/configs/<board>.h" for
3864 3. If you're porting U-Boot to a new CPU, then also create a new
3865 directory to hold your CPU specific code. Add any files you need.
3866 4. Run "make <board>_config" with your new name.
3867 5. Type "make", and you should get a working "u-boot.srec" file
3868 to be installed on your target system.
3869 6. Debug and solve any problems that might arise.
3870 [Of course, this last step is much harder than it sounds.]
3873 Testing of U-Boot Modifications, Ports to New Hardware, etc.:
3874 ==============================================================
3876 If you have modified U-Boot sources (for instance added a new board
3877 or support for new devices, a new CPU, etc.) you are expected to
3878 provide feedback to the other developers. The feedback normally takes
3879 the form of a "patch", i. e. a context diff against a certain (latest
3880 official or latest in the git repository) version of U-Boot sources.
3882 But before you submit such a patch, please verify that your modifi-
3883 cation did not break existing code. At least make sure that *ALL* of
3884 the supported boards compile WITHOUT ANY compiler warnings. To do so,
3885 just run the "MAKEALL" script, which will configure and build U-Boot
3886 for ALL supported system. Be warned, this will take a while. You can
3887 select which (cross) compiler to use by passing a `CROSS_COMPILE'
3888 environment variable to the script, i. e. to use the ELDK cross tools
3891 CROSS_COMPILE=ppc_8xx- MAKEALL
3893 or to build on a native PowerPC system you can type
3895 CROSS_COMPILE=' ' MAKEALL
3897 When using the MAKEALL script, the default behaviour is to build
3898 U-Boot in the source directory. This location can be changed by
3899 setting the BUILD_DIR environment variable. Also, for each target
3900 built, the MAKEALL script saves two log files (<target>.ERR and
3901 <target>.MAKEALL) in the <source dir>/LOG directory. This default
3902 location can be changed by setting the MAKEALL_LOGDIR environment
3903 variable. For example:
3905 export BUILD_DIR=/tmp/build
3906 export MAKEALL_LOGDIR=/tmp/log
3907 CROSS_COMPILE=ppc_8xx- MAKEALL
3909 With the above settings build objects are saved in the /tmp/build,
3910 log files are saved in the /tmp/log and the source tree remains clean
3911 during the whole build process.
3914 See also "U-Boot Porting Guide" below.
3917 Monitor Commands - Overview:
3918 ============================
3920 go - start application at address 'addr'
3921 run - run commands in an environment variable
3922 bootm - boot application image from memory
3923 bootp - boot image via network using BootP/TFTP protocol
3924 bootz - boot zImage from memory
3925 tftpboot- boot image via network using TFTP protocol
3926 and env variables "ipaddr" and "serverip"
3927 (and eventually "gatewayip")
3928 tftpput - upload a file via network using TFTP protocol
3929 rarpboot- boot image via network using RARP/TFTP protocol
3930 diskboot- boot from IDE devicebootd - boot default, i.e., run 'bootcmd'
3931 loads - load S-Record file over serial line
3932 loadb - load binary file over serial line (kermit mode)
3934 mm - memory modify (auto-incrementing)
3935 nm - memory modify (constant address)
3936 mw - memory write (fill)
3938 cmp - memory compare
3939 crc32 - checksum calculation
3940 i2c - I2C sub-system
3941 sspi - SPI utility commands
3942 base - print or set address offset
3943 printenv- print environment variables
3944 setenv - set environment variables
3945 saveenv - save environment variables to persistent storage
3946 protect - enable or disable FLASH write protection
3947 erase - erase FLASH memory
3948 flinfo - print FLASH memory information
3949 nand - NAND memory operations (see doc/README.nand)
3950 bdinfo - print Board Info structure
3951 iminfo - print header information for application image
3952 coninfo - print console devices and informations
3953 ide - IDE sub-system
3954 loop - infinite loop on address range
3955 loopw - infinite write loop on address range
3956 mtest - simple RAM test
3957 icache - enable or disable instruction cache
3958 dcache - enable or disable data cache
3959 reset - Perform RESET of the CPU
3960 echo - echo args to console
3961 version - print monitor version
3962 help - print online help
3963 ? - alias for 'help'
3966 Monitor Commands - Detailed Description:
3967 ========================================
3971 For now: just type "help <command>".
3974 Environment Variables:
3975 ======================
3977 U-Boot supports user configuration using Environment Variables which
3978 can be made persistent by saving to Flash memory.
3980 Environment Variables are set using "setenv", printed using
3981 "printenv", and saved to Flash using "saveenv". Using "setenv"
3982 without a value can be used to delete a variable from the
3983 environment. As long as you don't save the environment you are
3984 working with an in-memory copy. In case the Flash area containing the
3985 environment is erased by accident, a default environment is provided.
3987 Some configuration options can be set using Environment Variables.
3989 List of environment variables (most likely not complete):
3991 baudrate - see CONFIG_BAUDRATE
3993 bootdelay - see CONFIG_BOOTDELAY
3995 bootcmd - see CONFIG_BOOTCOMMAND
3997 bootargs - Boot arguments when booting an RTOS image
3999 bootfile - Name of the image to load with TFTP
4001 bootm_low - Memory range available for image processing in the bootm
4002 command can be restricted. This variable is given as
4003 a hexadecimal number and defines lowest address allowed
4004 for use by the bootm command. See also "bootm_size"
4005 environment variable. Address defined by "bootm_low" is
4006 also the base of the initial memory mapping for the Linux
4007 kernel -- see the description of CONFIG_SYS_BOOTMAPSZ and
4010 bootm_mapsize - Size of the initial memory mapping for the Linux kernel.
4011 This variable is given as a hexadecimal number and it
4012 defines the size of the memory region starting at base
4013 address bootm_low that is accessible by the Linux kernel
4014 during early boot. If unset, CONFIG_SYS_BOOTMAPSZ is used
4015 as the default value if it is defined, and bootm_size is
4018 bootm_size - Memory range available for image processing in the bootm
4019 command can be restricted. This variable is given as
4020 a hexadecimal number and defines the size of the region
4021 allowed for use by the bootm command. See also "bootm_low"
4022 environment variable.
4024 updatefile - Location of the software update file on a TFTP server, used
4025 by the automatic software update feature. Please refer to
4026 documentation in doc/README.update for more details.
4028 autoload - if set to "no" (any string beginning with 'n'),
4029 "bootp" will just load perform a lookup of the
4030 configuration from the BOOTP server, but not try to
4031 load any image using TFTP
4033 autostart - if set to "yes", an image loaded using the "bootp",
4034 "rarpboot", "tftpboot" or "diskboot" commands will
4035 be automatically started (by internally calling
4038 If set to "no", a standalone image passed to the
4039 "bootm" command will be copied to the load address
4040 (and eventually uncompressed), but NOT be started.
4041 This can be used to load and uncompress arbitrary
4044 fdt_high - if set this restricts the maximum address that the
4045 flattened device tree will be copied into upon boot.
4046 For example, if you have a system with 1 GB memory
4047 at physical address 0x10000000, while Linux kernel
4048 only recognizes the first 704 MB as low memory, you
4049 may need to set fdt_high as 0x3C000000 to have the
4050 device tree blob be copied to the maximum address
4051 of the 704 MB low memory, so that Linux kernel can
4052 access it during the boot procedure.
4054 If this is set to the special value 0xFFFFFFFF then
4055 the fdt will not be copied at all on boot. For this
4056 to work it must reside in writable memory, have
4057 sufficient padding on the end of it for u-boot to
4058 add the information it needs into it, and the memory
4059 must be accessible by the kernel.
4061 fdtcontroladdr- if set this is the address of the control flattened
4062 device tree used by U-Boot when CONFIG_OF_CONTROL is
4065 i2cfast - (PPC405GP|PPC405EP only)
4066 if set to 'y' configures Linux I2C driver for fast
4067 mode (400kHZ). This environment variable is used in
4068 initialization code. So, for changes to be effective
4069 it must be saved and board must be reset.
4071 initrd_high - restrict positioning of initrd images:
4072 If this variable is not set, initrd images will be
4073 copied to the highest possible address in RAM; this
4074 is usually what you want since it allows for
4075 maximum initrd size. If for some reason you want to
4076 make sure that the initrd image is loaded below the
4077 CONFIG_SYS_BOOTMAPSZ limit, you can set this environment
4078 variable to a value of "no" or "off" or "0".
4079 Alternatively, you can set it to a maximum upper
4080 address to use (U-Boot will still check that it
4081 does not overwrite the U-Boot stack and data).
4083 For instance, when you have a system with 16 MB
4084 RAM, and want to reserve 4 MB from use by Linux,
4085 you can do this by adding "mem=12M" to the value of
4086 the "bootargs" variable. However, now you must make
4087 sure that the initrd image is placed in the first
4088 12 MB as well - this can be done with
4090 setenv initrd_high 00c00000
4092 If you set initrd_high to 0xFFFFFFFF, this is an
4093 indication to U-Boot that all addresses are legal
4094 for the Linux kernel, including addresses in flash
4095 memory. In this case U-Boot will NOT COPY the
4096 ramdisk at all. This may be useful to reduce the
4097 boot time on your system, but requires that this
4098 feature is supported by your Linux kernel.
4100 ipaddr - IP address; needed for tftpboot command
4102 loadaddr - Default load address for commands like "bootp",
4103 "rarpboot", "tftpboot", "loadb" or "diskboot"
4105 loads_echo - see CONFIG_LOADS_ECHO
4107 serverip - TFTP server IP address; needed for tftpboot command
4109 bootretry - see CONFIG_BOOT_RETRY_TIME
4111 bootdelaykey - see CONFIG_AUTOBOOT_DELAY_STR
4113 bootstopkey - see CONFIG_AUTOBOOT_STOP_STR
4115 ethprime - controls which interface is used first.
4117 ethact - controls which interface is currently active.
4118 For example you can do the following
4120 => setenv ethact FEC
4121 => ping 192.168.0.1 # traffic sent on FEC
4122 => setenv ethact SCC
4123 => ping 10.0.0.1 # traffic sent on SCC
4125 ethrotate - When set to "no" U-Boot does not go through all
4126 available network interfaces.
4127 It just stays at the currently selected interface.
4129 netretry - When set to "no" each network operation will
4130 either succeed or fail without retrying.
4131 When set to "once" the network operation will
4132 fail when all the available network interfaces
4133 are tried once without success.
4134 Useful on scripts which control the retry operation
4137 npe_ucode - set load address for the NPE microcode
4139 tftpsrcport - If this is set, the value is used for TFTP's
4142 tftpdstport - If this is set, the value is used for TFTP's UDP
4143 destination port instead of the Well Know Port 69.
4145 tftpblocksize - Block size to use for TFTP transfers; if not set,
4146 we use the TFTP server's default block size
4148 tftptimeout - Retransmission timeout for TFTP packets (in milli-
4149 seconds, minimum value is 1000 = 1 second). Defines
4150 when a packet is considered to be lost so it has to
4151 be retransmitted. The default is 5000 = 5 seconds.
4152 Lowering this value may make downloads succeed
4153 faster in networks with high packet loss rates or
4154 with unreliable TFTP servers.
4156 vlan - When set to a value < 4095 the traffic over
4157 Ethernet is encapsulated/received over 802.1q
4160 The following image location variables contain the location of images
4161 used in booting. The "Image" column gives the role of the image and is
4162 not an environment variable name. The other columns are environment
4163 variable names. "File Name" gives the name of the file on a TFTP
4164 server, "RAM Address" gives the location in RAM the image will be
4165 loaded to, and "Flash Location" gives the image's address in NOR
4166 flash or offset in NAND flash.
4168 *Note* - these variables don't have to be defined for all boards, some
4169 boards currenlty use other variables for these purposes, and some
4170 boards use these variables for other purposes.
4172 Image File Name RAM Address Flash Location
4173 ----- --------- ----------- --------------
4174 u-boot u-boot u-boot_addr_r u-boot_addr
4175 Linux kernel bootfile kernel_addr_r kernel_addr
4176 device tree blob fdtfile fdt_addr_r fdt_addr
4177 ramdisk ramdiskfile ramdisk_addr_r ramdisk_addr
4179 The following environment variables may be used and automatically
4180 updated by the network boot commands ("bootp" and "rarpboot"),
4181 depending the information provided by your boot server:
4183 bootfile - see above
4184 dnsip - IP address of your Domain Name Server
4185 dnsip2 - IP address of your secondary Domain Name Server
4186 gatewayip - IP address of the Gateway (Router) to use
4187 hostname - Target hostname
4189 netmask - Subnet Mask
4190 rootpath - Pathname of the root filesystem on the NFS server
4191 serverip - see above
4194 There are two special Environment Variables:
4196 serial# - contains hardware identification information such
4197 as type string and/or serial number
4198 ethaddr - Ethernet address
4200 These variables can be set only once (usually during manufacturing of
4201 the board). U-Boot refuses to delete or overwrite these variables
4202 once they have been set once.
4205 Further special Environment Variables:
4207 ver - Contains the U-Boot version string as printed
4208 with the "version" command. This variable is
4209 readonly (see CONFIG_VERSION_VARIABLE).
4212 Please note that changes to some configuration parameters may take
4213 only effect after the next boot (yes, that's just like Windoze :-).
4216 Command Line Parsing:
4217 =====================
4219 There are two different command line parsers available with U-Boot:
4220 the old "simple" one, and the much more powerful "hush" shell:
4222 Old, simple command line parser:
4223 --------------------------------
4225 - supports environment variables (through setenv / saveenv commands)
4226 - several commands on one line, separated by ';'
4227 - variable substitution using "... ${name} ..." syntax
4228 - special characters ('$', ';') can be escaped by prefixing with '\',
4230 setenv bootcmd bootm \${address}
4231 - You can also escape text by enclosing in single apostrophes, for example:
4232 setenv addip 'setenv bootargs $bootargs ip=$ipaddr:$serverip:$gatewayip:$netmask:$hostname::off'
4237 - similar to Bourne shell, with control structures like
4238 if...then...else...fi, for...do...done; while...do...done,
4239 until...do...done, ...
4240 - supports environment ("global") variables (through setenv / saveenv
4241 commands) and local shell variables (through standard shell syntax
4242 "name=value"); only environment variables can be used with "run"
4248 (1) If a command line (or an environment variable executed by a "run"
4249 command) contains several commands separated by semicolon, and
4250 one of these commands fails, then the remaining commands will be
4253 (2) If you execute several variables with one call to run (i. e.
4254 calling run with a list of variables as arguments), any failing
4255 command will cause "run" to terminate, i. e. the remaining
4256 variables are not executed.
4258 Note for Redundant Ethernet Interfaces:
4259 =======================================
4261 Some boards come with redundant Ethernet interfaces; U-Boot supports
4262 such configurations and is capable of automatic selection of a
4263 "working" interface when needed. MAC assignment works as follows:
4265 Network interfaces are numbered eth0, eth1, eth2, ... Corresponding
4266 MAC addresses can be stored in the environment as "ethaddr" (=>eth0),
4267 "eth1addr" (=>eth1), "eth2addr", ...
4269 If the network interface stores some valid MAC address (for instance
4270 in SROM), this is used as default address if there is NO correspon-
4271 ding setting in the environment; if the corresponding environment
4272 variable is set, this overrides the settings in the card; that means:
4274 o If the SROM has a valid MAC address, and there is no address in the
4275 environment, the SROM's address is used.
4277 o If there is no valid address in the SROM, and a definition in the
4278 environment exists, then the value from the environment variable is
4281 o If both the SROM and the environment contain a MAC address, and
4282 both addresses are the same, this MAC address is used.
4284 o If both the SROM and the environment contain a MAC address, and the
4285 addresses differ, the value from the environment is used and a
4288 o If neither SROM nor the environment contain a MAC address, an error
4291 If Ethernet drivers implement the 'write_hwaddr' function, valid MAC addresses
4292 will be programmed into hardware as part of the initialization process. This
4293 may be skipped by setting the appropriate 'ethmacskip' environment variable.
4294 The naming convention is as follows:
4295 "ethmacskip" (=>eth0), "eth1macskip" (=>eth1) etc.
4300 U-Boot is capable of booting (and performing other auxiliary operations on)
4301 images in two formats:
4303 New uImage format (FIT)
4304 -----------------------
4306 Flexible and powerful format based on Flattened Image Tree -- FIT (similar
4307 to Flattened Device Tree). It allows the use of images with multiple
4308 components (several kernels, ramdisks, etc.), with contents protected by
4309 SHA1, MD5 or CRC32. More details are found in the doc/uImage.FIT directory.
4315 Old image format is based on binary files which can be basically anything,
4316 preceded by a special header; see the definitions in include/image.h for
4317 details; basically, the header defines the following image properties:
4319 * Target Operating System (Provisions for OpenBSD, NetBSD, FreeBSD,
4320 4.4BSD, Linux, SVR4, Esix, Solaris, Irix, SCO, Dell, NCR, VxWorks,
4321 LynxOS, pSOS, QNX, RTEMS, INTEGRITY;
4322 Currently supported: Linux, NetBSD, VxWorks, QNX, RTEMS, LynxOS,
4324 * Target CPU Architecture (Provisions for Alpha, ARM, AVR32, Intel x86,
4325 IA64, MIPS, NDS32, Nios II, PowerPC, IBM S390, SuperH, Sparc, Sparc 64 Bit;
4326 Currently supported: ARM, AVR32, Intel x86, MIPS, NDS32, Nios II, PowerPC).
4327 * Compression Type (uncompressed, gzip, bzip2)
4333 The header is marked by a special Magic Number, and both the header
4334 and the data portions of the image are secured against corruption by
4341 Although U-Boot should support any OS or standalone application
4342 easily, the main focus has always been on Linux during the design of
4345 U-Boot includes many features that so far have been part of some
4346 special "boot loader" code within the Linux kernel. Also, any
4347 "initrd" images to be used are no longer part of one big Linux image;
4348 instead, kernel and "initrd" are separate images. This implementation
4349 serves several purposes:
4351 - the same features can be used for other OS or standalone
4352 applications (for instance: using compressed images to reduce the
4353 Flash memory footprint)
4355 - it becomes much easier to port new Linux kernel versions because
4356 lots of low-level, hardware dependent stuff are done by U-Boot
4358 - the same Linux kernel image can now be used with different "initrd"
4359 images; of course this also means that different kernel images can
4360 be run with the same "initrd". This makes testing easier (you don't
4361 have to build a new "zImage.initrd" Linux image when you just
4362 change a file in your "initrd"). Also, a field-upgrade of the
4363 software is easier now.
4369 Porting Linux to U-Boot based systems:
4370 ---------------------------------------
4372 U-Boot cannot save you from doing all the necessary modifications to
4373 configure the Linux device drivers for use with your target hardware
4374 (no, we don't intend to provide a full virtual machine interface to
4377 But now you can ignore ALL boot loader code (in arch/powerpc/mbxboot).
4379 Just make sure your machine specific header file (for instance
4380 include/asm-ppc/tqm8xx.h) includes the same definition of the Board
4381 Information structure as we define in include/asm-<arch>/u-boot.h,
4382 and make sure that your definition of IMAP_ADDR uses the same value
4383 as your U-Boot configuration in CONFIG_SYS_IMMR.
4386 Configuring the Linux kernel:
4387 -----------------------------
4389 No specific requirements for U-Boot. Make sure you have some root
4390 device (initial ramdisk, NFS) for your target system.
4393 Building a Linux Image:
4394 -----------------------
4396 With U-Boot, "normal" build targets like "zImage" or "bzImage" are
4397 not used. If you use recent kernel source, a new build target
4398 "uImage" will exist which automatically builds an image usable by
4399 U-Boot. Most older kernels also have support for a "pImage" target,
4400 which was introduced for our predecessor project PPCBoot and uses a
4401 100% compatible format.
4410 The "uImage" build target uses a special tool (in 'tools/mkimage') to
4411 encapsulate a compressed Linux kernel image with header information,
4412 CRC32 checksum etc. for use with U-Boot. This is what we are doing:
4414 * build a standard "vmlinux" kernel image (in ELF binary format):
4416 * convert the kernel into a raw binary image:
4418 ${CROSS_COMPILE}-objcopy -O binary \
4419 -R .note -R .comment \
4420 -S vmlinux linux.bin
4422 * compress the binary image:
4426 * package compressed binary image for U-Boot:
4428 mkimage -A ppc -O linux -T kernel -C gzip \
4429 -a 0 -e 0 -n "Linux Kernel Image" \
4430 -d linux.bin.gz uImage
4433 The "mkimage" tool can also be used to create ramdisk images for use
4434 with U-Boot, either separated from the Linux kernel image, or
4435 combined into one file. "mkimage" encapsulates the images with a 64
4436 byte header containing information about target architecture,
4437 operating system, image type, compression method, entry points, time
4438 stamp, CRC32 checksums, etc.
4440 "mkimage" can be called in two ways: to verify existing images and
4441 print the header information, or to build new images.
4443 In the first form (with "-l" option) mkimage lists the information
4444 contained in the header of an existing U-Boot image; this includes
4445 checksum verification:
4447 tools/mkimage -l image
4448 -l ==> list image header information
4450 The second form (with "-d" option) is used to build a U-Boot image
4451 from a "data file" which is used as image payload:
4453 tools/mkimage -A arch -O os -T type -C comp -a addr -e ep \
4454 -n name -d data_file image
4455 -A ==> set architecture to 'arch'
4456 -O ==> set operating system to 'os'
4457 -T ==> set image type to 'type'
4458 -C ==> set compression type 'comp'
4459 -a ==> set load address to 'addr' (hex)
4460 -e ==> set entry point to 'ep' (hex)
4461 -n ==> set image name to 'name'
4462 -d ==> use image data from 'datafile'
4464 Right now, all Linux kernels for PowerPC systems use the same load
4465 address (0x00000000), but the entry point address depends on the
4468 - 2.2.x kernels have the entry point at 0x0000000C,
4469 - 2.3.x and later kernels have the entry point at 0x00000000.
4471 So a typical call to build a U-Boot image would read:
4473 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \
4474 > -A ppc -O linux -T kernel -C gzip -a 0 -e 0 \
4475 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux.gz \
4476 > examples/uImage.TQM850L
4477 Image Name: 2.4.4 kernel for TQM850L
4478 Created: Wed Jul 19 02:34:59 2000
4479 Image Type: PowerPC Linux Kernel Image (gzip compressed)
4480 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB
4481 Load Address: 0x00000000
4482 Entry Point: 0x00000000
4484 To verify the contents of the image (or check for corruption):
4486 -> tools/mkimage -l examples/uImage.TQM850L
4487 Image Name: 2.4.4 kernel for TQM850L
4488 Created: Wed Jul 19 02:34:59 2000
4489 Image Type: PowerPC Linux Kernel Image (gzip compressed)
4490 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB
4491 Load Address: 0x00000000
4492 Entry Point: 0x00000000
4494 NOTE: for embedded systems where boot time is critical you can trade
4495 speed for memory and install an UNCOMPRESSED image instead: this
4496 needs more space in Flash, but boots much faster since it does not
4497 need to be uncompressed:
4499 -> gunzip /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux.gz
4500 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \
4501 > -A ppc -O linux -T kernel -C none -a 0 -e 0 \
4502 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux \
4503 > examples/uImage.TQM850L-uncompressed
4504 Image Name: 2.4.4 kernel for TQM850L
4505 Created: Wed Jul 19 02:34:59 2000
4506 Image Type: PowerPC Linux Kernel Image (uncompressed)
4507 Data Size: 792160 Bytes = 773.59 kB = 0.76 MB
4508 Load Address: 0x00000000
4509 Entry Point: 0x00000000
4512 Similar you can build U-Boot images from a 'ramdisk.image.gz' file
4513 when your kernel is intended to use an initial ramdisk:
4515 -> tools/mkimage -n 'Simple Ramdisk Image' \
4516 > -A ppc -O linux -T ramdisk -C gzip \
4517 > -d /LinuxPPC/images/SIMPLE-ramdisk.image.gz examples/simple-initrd
4518 Image Name: Simple Ramdisk Image
4519 Created: Wed Jan 12 14:01:50 2000
4520 Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
4521 Data Size: 566530 Bytes = 553.25 kB = 0.54 MB
4522 Load Address: 0x00000000
4523 Entry Point: 0x00000000
4526 Installing a Linux Image:
4527 -------------------------
4529 To downloading a U-Boot image over the serial (console) interface,
4530 you must convert the image to S-Record format:
4532 objcopy -I binary -O srec examples/image examples/image.srec
4534 The 'objcopy' does not understand the information in the U-Boot
4535 image header, so the resulting S-Record file will be relative to
4536 address 0x00000000. To load it to a given address, you need to
4537 specify the target address as 'offset' parameter with the 'loads'
4540 Example: install the image to address 0x40100000 (which on the
4541 TQM8xxL is in the first Flash bank):
4543 => erase 40100000 401FFFFF
4549 ## Ready for S-Record download ...
4550 ~>examples/image.srec
4551 1 2 3 4 5 6 7 8 9 10 11 12 13 ...
4553 15989 15990 15991 15992
4554 [file transfer complete]
4556 ## Start Addr = 0x00000000
4559 You can check the success of the download using the 'iminfo' command;
4560 this includes a checksum verification so you can be sure no data
4561 corruption happened:
4565 ## Checking Image at 40100000 ...
4566 Image Name: 2.2.13 for initrd on TQM850L
4567 Image Type: PowerPC Linux Kernel Image (gzip compressed)
4568 Data Size: 335725 Bytes = 327 kB = 0 MB
4569 Load Address: 00000000
4570 Entry Point: 0000000c
4571 Verifying Checksum ... OK
4577 The "bootm" command is used to boot an application that is stored in
4578 memory (RAM or Flash). In case of a Linux kernel image, the contents
4579 of the "bootargs" environment variable is passed to the kernel as
4580 parameters. You can check and modify this variable using the
4581 "printenv" and "setenv" commands:
4584 => printenv bootargs
4585 bootargs=root=/dev/ram
4587 => setenv bootargs root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
4589 => printenv bootargs
4590 bootargs=root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
4593 ## Booting Linux kernel at 40020000 ...
4594 Image Name: 2.2.13 for NFS on TQM850L
4595 Image Type: PowerPC Linux Kernel Image (gzip compressed)
4596 Data Size: 381681 Bytes = 372 kB = 0 MB
4597 Load Address: 00000000
4598 Entry Point: 0000000c
4599 Verifying Checksum ... OK
4600 Uncompressing Kernel Image ... OK
4601 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
4602 Boot arguments: root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
4603 time_init: decrementer frequency = 187500000/60
4604 Calibrating delay loop... 49.77 BogoMIPS
4605 Memory: 15208k available (700k kernel code, 444k data, 32k init) [c0000000,c1000000]
4608 If you want to boot a Linux kernel with initial RAM disk, you pass
4609 the memory addresses of both the kernel and the initrd image (PPBCOOT
4610 format!) to the "bootm" command:
4612 => imi 40100000 40200000
4614 ## Checking Image at 40100000 ...
4615 Image Name: 2.2.13 for initrd on TQM850L
4616 Image Type: PowerPC Linux Kernel Image (gzip compressed)
4617 Data Size: 335725 Bytes = 327 kB = 0 MB
4618 Load Address: 00000000
4619 Entry Point: 0000000c
4620 Verifying Checksum ... OK
4622 ## Checking Image at 40200000 ...
4623 Image Name: Simple Ramdisk Image
4624 Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
4625 Data Size: 566530 Bytes = 553 kB = 0 MB
4626 Load Address: 00000000
4627 Entry Point: 00000000
4628 Verifying Checksum ... OK
4630 => bootm 40100000 40200000
4631 ## Booting Linux kernel at 40100000 ...
4632 Image Name: 2.2.13 for initrd on TQM850L
4633 Image Type: PowerPC Linux Kernel Image (gzip compressed)
4634 Data Size: 335725 Bytes = 327 kB = 0 MB
4635 Load Address: 00000000
4636 Entry Point: 0000000c
4637 Verifying Checksum ... OK
4638 Uncompressing Kernel Image ... OK
4639 ## Loading RAMDisk Image at 40200000 ...
4640 Image Name: Simple Ramdisk Image
4641 Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
4642 Data Size: 566530 Bytes = 553 kB = 0 MB
4643 Load Address: 00000000
4644 Entry Point: 00000000
4645 Verifying Checksum ... OK
4646 Loading Ramdisk ... OK
4647 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
4648 Boot arguments: root=/dev/ram
4649 time_init: decrementer frequency = 187500000/60
4650 Calibrating delay loop... 49.77 BogoMIPS
4652 RAMDISK: Compressed image found at block 0
4653 VFS: Mounted root (ext2 filesystem).
4657 Boot Linux and pass a flat device tree:
4660 First, U-Boot must be compiled with the appropriate defines. See the section
4661 titled "Linux Kernel Interface" above for a more in depth explanation. The
4662 following is an example of how to start a kernel and pass an updated
4668 oft=oftrees/mpc8540ads.dtb
4669 => tftp $oftaddr $oft
4670 Speed: 1000, full duplex
4672 TFTP from server 192.168.1.1; our IP address is 192.168.1.101
4673 Filename 'oftrees/mpc8540ads.dtb'.
4674 Load address: 0x300000
4677 Bytes transferred = 4106 (100a hex)
4678 => tftp $loadaddr $bootfile
4679 Speed: 1000, full duplex
4681 TFTP from server 192.168.1.1; our IP address is 192.168.1.2
4683 Load address: 0x200000
4684 Loading:############
4686 Bytes transferred = 1029407 (fb51f hex)
4691 => bootm $loadaddr - $oftaddr
4692 ## Booting image at 00200000 ...
4693 Image Name: Linux-2.6.17-dirty
4694 Image Type: PowerPC Linux Kernel Image (gzip compressed)
4695 Data Size: 1029343 Bytes = 1005.2 kB
4696 Load Address: 00000000
4697 Entry Point: 00000000
4698 Verifying Checksum ... OK
4699 Uncompressing Kernel Image ... OK
4700 Booting using flat device tree at 0x300000
4701 Using MPC85xx ADS machine description
4702 Memory CAM mapping: CAM0=256Mb, CAM1=256Mb, CAM2=0Mb residual: 0Mb
4706 More About U-Boot Image Types:
4707 ------------------------------
4709 U-Boot supports the following image types:
4711 "Standalone Programs" are directly runnable in the environment
4712 provided by U-Boot; it is expected that (if they behave
4713 well) you can continue to work in U-Boot after return from
4714 the Standalone Program.
4715 "OS Kernel Images" are usually images of some Embedded OS which
4716 will take over control completely. Usually these programs
4717 will install their own set of exception handlers, device
4718 drivers, set up the MMU, etc. - this means, that you cannot
4719 expect to re-enter U-Boot except by resetting the CPU.
4720 "RAMDisk Images" are more or less just data blocks, and their
4721 parameters (address, size) are passed to an OS kernel that is
4723 "Multi-File Images" contain several images, typically an OS
4724 (Linux) kernel image and one or more data images like
4725 RAMDisks. This construct is useful for instance when you want
4726 to boot over the network using BOOTP etc., where the boot
4727 server provides just a single image file, but you want to get
4728 for instance an OS kernel and a RAMDisk image.
4730 "Multi-File Images" start with a list of image sizes, each
4731 image size (in bytes) specified by an "uint32_t" in network
4732 byte order. This list is terminated by an "(uint32_t)0".
4733 Immediately after the terminating 0 follow the images, one by
4734 one, all aligned on "uint32_t" boundaries (size rounded up to
4735 a multiple of 4 bytes).
4737 "Firmware Images" are binary images containing firmware (like
4738 U-Boot or FPGA images) which usually will be programmed to
4741 "Script files" are command sequences that will be executed by
4742 U-Boot's command interpreter; this feature is especially
4743 useful when you configure U-Boot to use a real shell (hush)
4744 as command interpreter.
4746 Booting the Linux zImage:
4747 -------------------------
4749 On some platforms, it's possible to boot Linux zImage. This is done
4750 using the "bootz" command. The syntax of "bootz" command is the same
4751 as the syntax of "bootm" command.
4753 Note, defining the CONFIG_SUPPORT_INITRD_RAW allows user to supply
4754 kernel with raw initrd images. The syntax is slightly different, the
4755 address of the initrd must be augmented by it's size, in the following
4756 format: "<initrd addres>:<initrd size>".
4762 One of the features of U-Boot is that you can dynamically load and
4763 run "standalone" applications, which can use some resources of
4764 U-Boot like console I/O functions or interrupt services.
4766 Two simple examples are included with the sources:
4771 'examples/hello_world.c' contains a small "Hello World" Demo
4772 application; it is automatically compiled when you build U-Boot.
4773 It's configured to run at address 0x00040004, so you can play with it
4777 ## Ready for S-Record download ...
4778 ~>examples/hello_world.srec
4779 1 2 3 4 5 6 7 8 9 10 11 ...
4780 [file transfer complete]
4782 ## Start Addr = 0x00040004
4784 => go 40004 Hello World! This is a test.
4785 ## Starting application at 0x00040004 ...
4796 Hit any key to exit ...
4798 ## Application terminated, rc = 0x0
4800 Another example, which demonstrates how to register a CPM interrupt
4801 handler with the U-Boot code, can be found in 'examples/timer.c'.
4802 Here, a CPM timer is set up to generate an interrupt every second.
4803 The interrupt service routine is trivial, just printing a '.'
4804 character, but this is just a demo program. The application can be
4805 controlled by the following keys:
4807 ? - print current values og the CPM Timer registers
4808 b - enable interrupts and start timer
4809 e - stop timer and disable interrupts
4810 q - quit application
4813 ## Ready for S-Record download ...
4814 ~>examples/timer.srec
4815 1 2 3 4 5 6 7 8 9 10 11 ...
4816 [file transfer complete]
4818 ## Start Addr = 0x00040004
4821 ## Starting application at 0x00040004 ...
4824 tgcr @ 0xfff00980, tmr @ 0xfff00990, trr @ 0xfff00994, tcr @ 0xfff00998, tcn @ 0xfff0099c, ter @ 0xfff009b0
4827 [q, b, e, ?] Set interval 1000000 us
4830 [q, b, e, ?] ........
4831 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0xef6, ter=0x0
4834 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x2ad4, ter=0x0
4837 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x1efc, ter=0x0
4840 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x169d, ter=0x0
4842 [q, b, e, ?] ...Stopping timer
4844 [q, b, e, ?] ## Application terminated, rc = 0x0
4850 Over time, many people have reported problems when trying to use the
4851 "minicom" terminal emulation program for serial download. I (wd)
4852 consider minicom to be broken, and recommend not to use it. Under
4853 Unix, I recommend to use C-Kermit for general purpose use (and
4854 especially for kermit binary protocol download ("loadb" command), and
4855 use "cu" for S-Record download ("loads" command). See
4856 http://www.denx.de/wiki/view/DULG/SystemSetup#Section_4.3.
4857 for help with kermit.
4860 Nevertheless, if you absolutely want to use it try adding this
4861 configuration to your "File transfer protocols" section:
4863 Name Program Name U/D FullScr IO-Red. Multi
4864 X kermit /usr/bin/kermit -i -l %l -s Y U Y N N
4865 Y kermit /usr/bin/kermit -i -l %l -r N D Y N N
4871 Starting at version 0.9.2, U-Boot supports NetBSD both as host
4872 (build U-Boot) and target system (boots NetBSD/mpc8xx).
4874 Building requires a cross environment; it is known to work on
4875 NetBSD/i386 with the cross-powerpc-netbsd-1.3 package (you will also
4876 need gmake since the Makefiles are not compatible with BSD make).
4877 Note that the cross-powerpc package does not install include files;
4878 attempting to build U-Boot will fail because <machine/ansi.h> is
4879 missing. This file has to be installed and patched manually:
4881 # cd /usr/pkg/cross/powerpc-netbsd/include
4883 # ln -s powerpc machine
4884 # cp /usr/src/sys/arch/powerpc/include/ansi.h powerpc/ansi.h
4885 # ${EDIT} powerpc/ansi.h ## must remove __va_list, _BSD_VA_LIST
4887 Native builds *don't* work due to incompatibilities between native
4888 and U-Boot include files.
4890 Booting assumes that (the first part of) the image booted is a
4891 stage-2 loader which in turn loads and then invokes the kernel
4892 proper. Loader sources will eventually appear in the NetBSD source
4893 tree (probably in sys/arc/mpc8xx/stand/u-boot_stage2/); in the
4894 meantime, see ftp://ftp.denx.de/pub/u-boot/ppcboot_stage2.tar.gz
4897 Implementation Internals:
4898 =========================
4900 The following is not intended to be a complete description of every
4901 implementation detail. However, it should help to understand the
4902 inner workings of U-Boot and make it easier to port it to custom
4906 Initial Stack, Global Data:
4907 ---------------------------
4909 The implementation of U-Boot is complicated by the fact that U-Boot
4910 starts running out of ROM (flash memory), usually without access to
4911 system RAM (because the memory controller is not initialized yet).
4912 This means that we don't have writable Data or BSS segments, and BSS
4913 is not initialized as zero. To be able to get a C environment working
4914 at all, we have to allocate at least a minimal stack. Implementation
4915 options for this are defined and restricted by the CPU used: Some CPU
4916 models provide on-chip memory (like the IMMR area on MPC8xx and
4917 MPC826x processors), on others (parts of) the data cache can be
4918 locked as (mis-) used as memory, etc.
4920 Chris Hallinan posted a good summary of these issues to the
4921 U-Boot mailing list:
4923 Subject: RE: [U-Boot-Users] RE: More On Memory Bank x (nothingness)?
4924 From: "Chris Hallinan" <clh@net1plus.com>
4925 Date: Mon, 10 Feb 2003 16:43:46 -0500 (22:43 MET)
4928 Correct me if I'm wrong, folks, but the way I understand it
4929 is this: Using DCACHE as initial RAM for Stack, etc, does not
4930 require any physical RAM backing up the cache. The cleverness
4931 is that the cache is being used as a temporary supply of
4932 necessary storage before the SDRAM controller is setup. It's
4933 beyond the scope of this list to explain the details, but you
4934 can see how this works by studying the cache architecture and
4935 operation in the architecture and processor-specific manuals.
4937 OCM is On Chip Memory, which I believe the 405GP has 4K. It
4938 is another option for the system designer to use as an
4939 initial stack/RAM area prior to SDRAM being available. Either
4940 option should work for you. Using CS 4 should be fine if your
4941 board designers haven't used it for something that would
4942 cause you grief during the initial boot! It is frequently not
4945 CONFIG_SYS_INIT_RAM_ADDR should be somewhere that won't interfere
4946 with your processor/board/system design. The default value
4947 you will find in any recent u-boot distribution in
4948 walnut.h should work for you. I'd set it to a value larger
4949 than your SDRAM module. If you have a 64MB SDRAM module, set
4950 it above 400_0000. Just make sure your board has no resources
4951 that are supposed to respond to that address! That code in
4952 start.S has been around a while and should work as is when
4953 you get the config right.
4958 It is essential to remember this, since it has some impact on the C
4959 code for the initialization procedures:
4961 * Initialized global data (data segment) is read-only. Do not attempt
4964 * Do not use any uninitialized global data (or implicitely initialized
4965 as zero data - BSS segment) at all - this is undefined, initiali-
4966 zation is performed later (when relocating to RAM).
4968 * Stack space is very limited. Avoid big data buffers or things like
4971 Having only the stack as writable memory limits means we cannot use
4972 normal global data to share information beween the code. But it
4973 turned out that the implementation of U-Boot can be greatly
4974 simplified by making a global data structure (gd_t) available to all
4975 functions. We could pass a pointer to this data as argument to _all_
4976 functions, but this would bloat the code. Instead we use a feature of
4977 the GCC compiler (Global Register Variables) to share the data: we
4978 place a pointer (gd) to the global data into a register which we
4979 reserve for this purpose.
4981 When choosing a register for such a purpose we are restricted by the
4982 relevant (E)ABI specifications for the current architecture, and by
4983 GCC's implementation.
4985 For PowerPC, the following registers have specific use:
4987 R2: reserved for system use
4988 R3-R4: parameter passing and return values
4989 R5-R10: parameter passing
4990 R13: small data area pointer
4994 (U-Boot also uses R12 as internal GOT pointer. r12
4995 is a volatile register so r12 needs to be reset when
4996 going back and forth between asm and C)
4998 ==> U-Boot will use R2 to hold a pointer to the global data
5000 Note: on PPC, we could use a static initializer (since the
5001 address of the global data structure is known at compile time),
5002 but it turned out that reserving a register results in somewhat
5003 smaller code - although the code savings are not that big (on
5004 average for all boards 752 bytes for the whole U-Boot image,
5005 624 text + 127 data).
5007 On Blackfin, the normal C ABI (except for P3) is followed as documented here:
5008 http://docs.blackfin.uclinux.org/doku.php?id=application_binary_interface
5010 ==> U-Boot will use P3 to hold a pointer to the global data
5012 On ARM, the following registers are used:
5014 R0: function argument word/integer result
5015 R1-R3: function argument word
5017 R10: stack limit (used only if stack checking if enabled)
5018 R11: argument (frame) pointer
5019 R12: temporary workspace
5022 R15: program counter
5024 ==> U-Boot will use R8 to hold a pointer to the global data
5026 On Nios II, the ABI is documented here:
5027 http://www.altera.com/literature/hb/nios2/n2cpu_nii51016.pdf
5029 ==> U-Boot will use gp to hold a pointer to the global data
5031 Note: on Nios II, we give "-G0" option to gcc and don't use gp
5032 to access small data sections, so gp is free.
5034 On NDS32, the following registers are used:
5036 R0-R1: argument/return
5038 R15: temporary register for assembler
5039 R16: trampoline register
5040 R28: frame pointer (FP)
5041 R29: global pointer (GP)
5042 R30: link register (LP)
5043 R31: stack pointer (SP)
5044 PC: program counter (PC)
5046 ==> U-Boot will use R10 to hold a pointer to the global data
5048 NOTE: DECLARE_GLOBAL_DATA_PTR must be used with file-global scope,
5049 or current versions of GCC may "optimize" the code too much.
5054 U-Boot runs in system state and uses physical addresses, i.e. the
5055 MMU is not used either for address mapping nor for memory protection.
5057 The available memory is mapped to fixed addresses using the memory
5058 controller. In this process, a contiguous block is formed for each
5059 memory type (Flash, SDRAM, SRAM), even when it consists of several
5060 physical memory banks.
5062 U-Boot is installed in the first 128 kB of the first Flash bank (on
5063 TQM8xxL modules this is the range 0x40000000 ... 0x4001FFFF). After
5064 booting and sizing and initializing DRAM, the code relocates itself
5065 to the upper end of DRAM. Immediately below the U-Boot code some
5066 memory is reserved for use by malloc() [see CONFIG_SYS_MALLOC_LEN
5067 configuration setting]. Below that, a structure with global Board
5068 Info data is placed, followed by the stack (growing downward).
5070 Additionally, some exception handler code is copied to the low 8 kB
5071 of DRAM (0x00000000 ... 0x00001FFF).
5073 So a typical memory configuration with 16 MB of DRAM could look like
5076 0x0000 0000 Exception Vector code
5079 0x0000 2000 Free for Application Use
5085 0x00FB FF20 Monitor Stack (Growing downward)
5086 0x00FB FFAC Board Info Data and permanent copy of global data
5087 0x00FC 0000 Malloc Arena
5090 0x00FE 0000 RAM Copy of Monitor Code
5091 ... eventually: LCD or video framebuffer
5092 ... eventually: pRAM (Protected RAM - unchanged by reset)
5093 0x00FF FFFF [End of RAM]
5096 System Initialization:
5097 ----------------------
5099 In the reset configuration, U-Boot starts at the reset entry point
5100 (on most PowerPC systems at address 0x00000100). Because of the reset
5101 configuration for CS0# this is a mirror of the onboard Flash memory.
5102 To be able to re-map memory U-Boot then jumps to its link address.
5103 To be able to implement the initialization code in C, a (small!)
5104 initial stack is set up in the internal Dual Ported RAM (in case CPUs
5105 which provide such a feature like MPC8xx or MPC8260), or in a locked
5106 part of the data cache. After that, U-Boot initializes the CPU core,
5107 the caches and the SIU.
5109 Next, all (potentially) available memory banks are mapped using a
5110 preliminary mapping. For example, we put them on 512 MB boundaries
5111 (multiples of 0x20000000: SDRAM on 0x00000000 and 0x20000000, Flash
5112 on 0x40000000 and 0x60000000, SRAM on 0x80000000). Then UPM A is
5113 programmed for SDRAM access. Using the temporary configuration, a
5114 simple memory test is run that determines the size of the SDRAM
5117 When there is more than one SDRAM bank, and the banks are of
5118 different size, the largest is mapped first. For equal size, the first
5119 bank (CS2#) is mapped first. The first mapping is always for address
5120 0x00000000, with any additional banks following immediately to create
5121 contiguous memory starting from 0.
5123 Then, the monitor installs itself at the upper end of the SDRAM area
5124 and allocates memory for use by malloc() and for the global Board
5125 Info data; also, the exception vector code is copied to the low RAM
5126 pages, and the final stack is set up.
5128 Only after this relocation will you have a "normal" C environment;
5129 until that you are restricted in several ways, mostly because you are
5130 running from ROM, and because the code will have to be relocated to a
5134 U-Boot Porting Guide:
5135 ----------------------
5137 [Based on messages by Jerry Van Baren in the U-Boot-Users mailing
5141 int main(int argc, char *argv[])
5143 sighandler_t no_more_time;
5145 signal(SIGALRM, no_more_time);
5146 alarm(PROJECT_DEADLINE - toSec (3 * WEEK));
5148 if (available_money > available_manpower) {
5149 Pay consultant to port U-Boot;
5153 Download latest U-Boot source;
5155 Subscribe to u-boot mailing list;
5158 email("Hi, I am new to U-Boot, how do I get started?");
5161 Read the README file in the top level directory;
5162 Read http://www.denx.de/twiki/bin/view/DULG/Manual;
5163 Read applicable doc/*.README;
5164 Read the source, Luke;
5165 /* find . -name "*.[chS]" | xargs grep -i <keyword> */
5168 if (available_money > toLocalCurrency ($2500))
5171 Add a lot of aggravation and time;
5173 if (a similar board exists) { /* hopefully... */
5174 cp -a board/<similar> board/<myboard>
5175 cp include/configs/<similar>.h include/configs/<myboard>.h
5177 Create your own board support subdirectory;
5178 Create your own board include/configs/<myboard>.h file;
5180 Edit new board/<myboard> files
5181 Edit new include/configs/<myboard>.h
5186 Add / modify source code;
5190 email("Hi, I am having problems...");
5192 Send patch file to the U-Boot email list;
5193 if (reasonable critiques)
5194 Incorporate improvements from email list code review;
5196 Defend code as written;
5202 void no_more_time (int sig)
5211 All contributions to U-Boot should conform to the Linux kernel
5212 coding style; see the file "Documentation/CodingStyle" and the script
5213 "scripts/Lindent" in your Linux kernel source directory.
5215 Source files originating from a different project (for example the
5216 MTD subsystem) are generally exempt from these guidelines and are not
5217 reformated to ease subsequent migration to newer versions of those
5220 Please note that U-Boot is implemented in C (and to some small parts in
5221 Assembler); no C++ is used, so please do not use C++ style comments (//)
5224 Please also stick to the following formatting rules:
5225 - remove any trailing white space
5226 - use TAB characters for indentation and vertical alignment, not spaces
5227 - make sure NOT to use DOS '\r\n' line feeds
5228 - do not add more than 2 consecutive empty lines to source files
5229 - do not add trailing empty lines to source files
5231 Submissions which do not conform to the standards may be returned
5232 with a request to reformat the changes.
5238 Since the number of patches for U-Boot is growing, we need to
5239 establish some rules. Submissions which do not conform to these rules
5240 may be rejected, even when they contain important and valuable stuff.
5242 Please see http://www.denx.de/wiki/U-Boot/Patches for details.
5244 Patches shall be sent to the u-boot mailing list <u-boot@lists.denx.de>;
5245 see http://lists.denx.de/mailman/listinfo/u-boot
5247 When you send a patch, please include the following information with
5250 * For bug fixes: a description of the bug and how your patch fixes
5251 this bug. Please try to include a way of demonstrating that the
5252 patch actually fixes something.
5254 * For new features: a description of the feature and your
5257 * A CHANGELOG entry as plaintext (separate from the patch)
5259 * For major contributions, your entry to the CREDITS file
5261 * When you add support for a new board, don't forget to add this
5262 board to the MAINTAINERS file, too.
5264 * If your patch adds new configuration options, don't forget to
5265 document these in the README file.
5267 * The patch itself. If you are using git (which is *strongly*
5268 recommended) you can easily generate the patch using the
5269 "git format-patch". If you then use "git send-email" to send it to
5270 the U-Boot mailing list, you will avoid most of the common problems
5271 with some other mail clients.
5273 If you cannot use git, use "diff -purN OLD NEW". If your version of
5274 diff does not support these options, then get the latest version of
5277 The current directory when running this command shall be the parent
5278 directory of the U-Boot source tree (i. e. please make sure that
5279 your patch includes sufficient directory information for the
5282 We prefer patches as plain text. MIME attachments are discouraged,
5283 and compressed attachments must not be used.
5285 * If one logical set of modifications affects or creates several
5286 files, all these changes shall be submitted in a SINGLE patch file.
5288 * Changesets that contain different, unrelated modifications shall be
5289 submitted as SEPARATE patches, one patch per changeset.
5294 * Before sending the patch, run the MAKEALL script on your patched
5295 source tree and make sure that no errors or warnings are reported
5296 for any of the boards.
5298 * Keep your modifications to the necessary minimum: A patch
5299 containing several unrelated changes or arbitrary reformats will be
5300 returned with a request to re-formatting / split it.
5302 * If you modify existing code, make sure that your new code does not
5303 add to the memory footprint of the code ;-) Small is beautiful!
5304 When adding new features, these should compile conditionally only
5305 (using #ifdef), and the resulting code with the new feature
5306 disabled must not need more memory than the old code without your
5309 * Remember that there is a size limit of 100 kB per message on the
5310 u-boot mailing list. Bigger patches will be moderated. If they are
5311 reasonable and not too big, they will be acknowledged. But patches
5312 bigger than the size limit should be avoided.
projects / karo-tx-uboot.git / blob