2 # (C) Copyright 2000 - 2011
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
61 In case you have questions about, problems with or contributions for
62 U-Boot you should send a message to the U-Boot mailing list at
63 <u-boot@lists.denx.de>. There is also an archive of previous traffic
64 on the mailing list - please search the archive before asking FAQ's.
65 Please see http://lists.denx.de/pipermail/u-boot and
66 http://dir.gmane.org/gmane.comp.boot-loaders.u-boot
69 Where to get source code:
70 =========================
72 The U-Boot source code is maintained in the git repository at
73 git://www.denx.de/git/u-boot.git ; you can browse it online at
74 http://www.denx.de/cgi-bin/gitweb.cgi?p=u-boot.git;a=summary
76 The "snapshot" links on this page allow you to download tarballs of
77 any version you might be interested in. Official releases are also
78 available for FTP download from the ftp://ftp.denx.de/pub/u-boot/
81 Pre-built (and tested) images are available from
82 ftp://ftp.denx.de/pub/u-boot/images/
88 - start from 8xxrom sources
89 - create PPCBoot project (http://sourceforge.net/projects/ppcboot)
91 - make it easier to add custom boards
92 - make it possible to add other [PowerPC] CPUs
93 - extend functions, especially:
94 * Provide extended interface to Linux boot loader
97 * PCMCIA / CompactFlash / ATA disk / SCSI ... boot
98 - create ARMBoot project (http://sourceforge.net/projects/armboot)
99 - add other CPU families (starting with ARM)
100 - create U-Boot project (http://sourceforge.net/projects/u-boot)
101 - current project page: see http://www.denx.de/wiki/U-Boot
107 The "official" name of this project is "Das U-Boot". The spelling
108 "U-Boot" shall be used in all written text (documentation, comments
109 in source files etc.). Example:
111 This is the README file for the U-Boot project.
113 File names etc. shall be based on the string "u-boot". Examples:
115 include/asm-ppc/u-boot.h
117 #include <asm/u-boot.h>
119 Variable names, preprocessor constants etc. shall be either based on
120 the string "u_boot" or on "U_BOOT". Example:
122 U_BOOT_VERSION u_boot_logo
123 IH_OS_U_BOOT u_boot_hush_start
129 Starting with the release in October 2008, the names of the releases
130 were changed from numerical release numbers without deeper meaning
131 into a time stamp based numbering. Regular releases are identified by
132 names consisting of the calendar year and month of the release date.
133 Additional fields (if present) indicate release candidates or bug fix
134 releases in "stable" maintenance trees.
137 U-Boot v2009.11 - Release November 2009
138 U-Boot v2009.11.1 - Release 1 in version November 2009 stable tree
139 U-Boot v2010.09-rc1 - Release candiate 1 for September 2010 release
145 /arch Architecture specific files
146 /arm Files generic to ARM architecture
147 /cpu CPU specific files
148 /arm720t Files specific to ARM 720 CPUs
149 /arm920t Files specific to ARM 920 CPUs
150 /at91rm9200 Files specific to Atmel AT91RM9200 CPU
151 /imx Files specific to Freescale MC9328 i.MX CPUs
152 /s3c24x0 Files specific to Samsung S3C24X0 CPUs
153 /arm925t Files specific to ARM 925 CPUs
154 /arm926ejs Files specific to ARM 926 CPUs
155 /arm1136 Files specific to ARM 1136 CPUs
156 /ixp Files specific to Intel XScale IXP CPUs
157 /pxa Files specific to Intel XScale PXA CPUs
158 /s3c44b0 Files specific to Samsung S3C44B0 CPUs
159 /sa1100 Files specific to Intel StrongARM SA1100 CPUs
160 /lib Architecture specific library files
161 /avr32 Files generic to AVR32 architecture
162 /cpu CPU specific files
163 /lib Architecture specific library files
164 /blackfin Files generic to Analog Devices Blackfin architecture
165 /cpu CPU specific files
166 /lib Architecture specific library files
167 /x86 Files generic to x86 architecture
168 /cpu CPU specific files
169 /lib Architecture specific library files
170 /m68k Files generic to m68k architecture
171 /cpu CPU specific files
172 /mcf52x2 Files specific to Freescale ColdFire MCF52x2 CPUs
173 /mcf5227x Files specific to Freescale ColdFire MCF5227x CPUs
174 /mcf532x Files specific to Freescale ColdFire MCF5329 CPUs
175 /mcf5445x Files specific to Freescale ColdFire MCF5445x CPUs
176 /mcf547x_8x Files specific to Freescale ColdFire MCF547x_8x CPUs
177 /lib Architecture specific library files
178 /microblaze Files generic to microblaze architecture
179 /cpu CPU specific files
180 /lib Architecture specific library files
181 /mips Files generic to MIPS architecture
182 /cpu CPU specific files
183 /lib Architecture specific library files
184 /nios2 Files generic to Altera NIOS2 architecture
185 /cpu CPU specific files
186 /lib Architecture specific library files
187 /powerpc Files generic to PowerPC architecture
188 /cpu CPU specific files
189 /74xx_7xx Files specific to Freescale MPC74xx and 7xx CPUs
190 /mpc5xx Files specific to Freescale MPC5xx CPUs
191 /mpc5xxx Files specific to Freescale MPC5xxx CPUs
192 /mpc8xx Files specific to Freescale MPC8xx CPUs
193 /mpc8220 Files specific to Freescale MPC8220 CPUs
194 /mpc824x Files specific to Freescale MPC824x CPUs
195 /mpc8260 Files specific to Freescale MPC8260 CPUs
196 /mpc85xx Files specific to Freescale MPC85xx CPUs
197 /ppc4xx Files specific to AMCC PowerPC 4xx CPUs
198 /lib Architecture specific library files
199 /sh Files generic to SH architecture
200 /cpu CPU specific files
201 /sh2 Files specific to sh2 CPUs
202 /sh3 Files specific to sh3 CPUs
203 /sh4 Files specific to sh4 CPUs
204 /lib Architecture specific library files
205 /sparc Files generic to SPARC architecture
206 /cpu CPU specific files
207 /leon2 Files specific to Gaisler LEON2 SPARC CPU
208 /leon3 Files specific to Gaisler LEON3 SPARC CPU
209 /lib Architecture specific library files
210 /api Machine/arch independent API for external apps
211 /board Board dependent files
212 /common Misc architecture independent functions
213 /disk Code for disk drive partition handling
214 /doc Documentation (don't expect too much)
215 /drivers Commonly used device drivers
216 /examples Example code for standalone applications, etc.
217 /fs Filesystem code (cramfs, ext2, jffs2, etc.)
218 /include Header Files
219 /lib Files generic to all architectures
220 /libfdt Library files to support flattened device trees
221 /lzma Library files to support LZMA decompression
222 /lzo Library files to support LZO decompression
224 /post Power On Self Test
225 /rtc Real Time Clock drivers
226 /tools Tools to build S-Record or U-Boot images, etc.
228 Software Configuration:
229 =======================
231 Configuration is usually done using C preprocessor defines; the
232 rationale behind that is to avoid dead code whenever possible.
234 There are two classes of configuration variables:
236 * Configuration _OPTIONS_:
237 These are selectable by the user and have names beginning with
240 * Configuration _SETTINGS_:
241 These depend on the hardware etc. and should not be meddled with if
242 you don't know what you're doing; they have names beginning with
245 Later we will add a configuration tool - probably similar to or even
246 identical to what's used for the Linux kernel. Right now, we have to
247 do the configuration by hand, which means creating some symbolic
248 links and editing some configuration files. We use the TQM8xxL boards
252 Selection of Processor Architecture and Board Type:
253 ---------------------------------------------------
255 For all supported boards there are ready-to-use default
256 configurations available; just type "make <board_name>_config".
258 Example: For a TQM823L module type:
263 For the Cogent platform, you need to specify the CPU type as well;
264 e.g. "make cogent_mpc8xx_config". And also configure the cogent
265 directory according to the instructions in cogent/README.
268 Configuration Options:
269 ----------------------
271 Configuration depends on the combination of board and CPU type; all
272 such information is kept in a configuration file
273 "include/configs/<board_name>.h".
275 Example: For a TQM823L module, all configuration settings are in
276 "include/configs/TQM823L.h".
279 Many of the options are named exactly as the corresponding Linux
280 kernel configuration options. The intention is to make it easier to
281 build a config tool - later.
284 The following options need to be configured:
286 - CPU Type: Define exactly one, e.g. CONFIG_MPC85XX.
288 - Board Type: Define exactly one, e.g. CONFIG_MPC8540ADS.
290 - CPU Daughterboard Type: (if CONFIG_ATSTK1000 is defined)
291 Define exactly one, e.g. CONFIG_ATSTK1002
293 - CPU Module Type: (if CONFIG_COGENT is defined)
294 Define exactly one of
296 --- FIXME --- not tested yet:
297 CONFIG_CMA286_60, CONFIG_CMA286_21, CONFIG_CMA286_60P,
298 CONFIG_CMA287_23, CONFIG_CMA287_50
300 - Motherboard Type: (if CONFIG_COGENT is defined)
301 Define exactly one of
302 CONFIG_CMA101, CONFIG_CMA102
304 - Motherboard I/O Modules: (if CONFIG_COGENT is defined)
305 Define one or more of
308 - Motherboard Options: (if CONFIG_CMA101 or CONFIG_CMA102 are defined)
309 Define one or more of
310 CONFIG_LCD_HEARTBEAT - update a character position on
311 the LCD display every second with
314 - Board flavour: (if CONFIG_MPC8260ADS is defined)
317 CONFIG_SYS_8260ADS - original MPC8260ADS
318 CONFIG_SYS_8266ADS - MPC8266ADS
319 CONFIG_SYS_PQ2FADS - PQ2FADS-ZU or PQ2FADS-VR
320 CONFIG_SYS_8272ADS - MPC8272ADS
322 - Marvell Family Member
323 CONFIG_SYS_MVFS - define it if you want to enable
324 multiple fs option at one time
325 for marvell soc family
327 - MPC824X Family Member (if CONFIG_MPC824X is defined)
328 Define exactly one of
329 CONFIG_MPC8240, CONFIG_MPC8245
331 - 8xx CPU Options: (if using an MPC8xx CPU)
332 CONFIG_8xx_GCLK_FREQ - deprecated: CPU clock if
333 get_gclk_freq() cannot work
334 e.g. if there is no 32KHz
335 reference PIT/RTC clock
336 CONFIG_8xx_OSCLK - PLL input clock (either EXTCLK
339 - 859/866/885 CPU options: (if using a MPC859 or MPC866 or MPC885 CPU):
340 CONFIG_SYS_8xx_CPUCLK_MIN
341 CONFIG_SYS_8xx_CPUCLK_MAX
342 CONFIG_8xx_CPUCLK_DEFAULT
343 See doc/README.MPC866
345 CONFIG_SYS_MEASURE_CPUCLK
347 Define this to measure the actual CPU clock instead
348 of relying on the correctness of the configured
349 values. Mostly useful for board bringup to make sure
350 the PLL is locked at the intended frequency. Note
351 that this requires a (stable) reference clock (32 kHz
352 RTC clock or CONFIG_SYS_8XX_XIN)
354 CONFIG_SYS_DELAYED_ICACHE
356 Define this option if you want to enable the
357 ICache only when Code runs from RAM.
360 CONFIG_SYS_FSL_TBCLK_DIV
362 Defines the core time base clock divider ratio compared to the
363 system clock. On most PQ3 devices this is 8, on newer QorIQ
364 devices it can be 16 or 32. The ratio varies from SoC to Soc.
366 CONFIG_SYS_FSL_PCIE_COMPAT
368 Defines the string to utilize when trying to match PCIe device
369 tree nodes for the given platform.
371 - Intel Monahans options:
372 CONFIG_SYS_MONAHANS_RUN_MODE_OSC_RATIO
374 Defines the Monahans run mode to oscillator
375 ratio. Valid values are 8, 16, 24, 31. The core
376 frequency is this value multiplied by 13 MHz.
378 CONFIG_SYS_MONAHANS_TURBO_RUN_MODE_RATIO
380 Defines the Monahans turbo mode to oscillator
381 ratio. Valid values are 1 (default if undefined) and
382 2. The core frequency as calculated above is multiplied
385 - Linux Kernel Interface:
388 U-Boot stores all clock information in Hz
389 internally. For binary compatibility with older Linux
390 kernels (which expect the clocks passed in the
391 bd_info data to be in MHz) the environment variable
392 "clocks_in_mhz" can be defined so that U-Boot
393 converts clock data to MHZ before passing it to the
395 When CONFIG_CLOCKS_IN_MHZ is defined, a definition of
396 "clocks_in_mhz=1" is automatically included in the
399 CONFIG_MEMSIZE_IN_BYTES [relevant for MIPS only]
401 When transferring memsize parameter to linux, some versions
402 expect it to be in bytes, others in MB.
403 Define CONFIG_MEMSIZE_IN_BYTES to make it in bytes.
407 New kernel versions are expecting firmware settings to be
408 passed using flattened device trees (based on open firmware
412 * New libfdt-based support
413 * Adds the "fdt" command
414 * The bootm command automatically updates the fdt
416 OF_CPU - The proper name of the cpus node (only required for
417 MPC512X and MPC5xxx based boards).
418 OF_SOC - The proper name of the soc node (only required for
419 MPC512X and MPC5xxx based boards).
420 OF_TBCLK - The timebase frequency.
421 OF_STDOUT_PATH - The path to the console device
423 boards with QUICC Engines require OF_QE to set UCC MAC
426 CONFIG_OF_BOARD_SETUP
428 Board code has addition modification that it wants to make
429 to the flat device tree before handing it off to the kernel
433 This define fills in the correct boot CPU in the boot
434 param header, the default value is zero if undefined.
438 U-Boot can detect if an IDE device is present or not.
439 If not, and this new config option is activated, U-Boot
440 removes the ATA node from the DTS before booting Linux,
441 so the Linux IDE driver does not probe the device and
442 crash. This is needed for buggy hardware (uc101) where
443 no pull down resistor is connected to the signal IDE5V_DD7.
445 - vxWorks boot parameters:
447 bootvx constructs a valid bootline using the following
448 environments variables: bootfile, ipaddr, serverip, hostname.
449 It loads the vxWorks image pointed bootfile.
451 CONFIG_SYS_VXWORKS_BOOT_DEVICE - The vxworks device name
452 CONFIG_SYS_VXWORKS_MAC_PTR - Ethernet 6 byte MA -address
453 CONFIG_SYS_VXWORKS_SERVERNAME - Name of the server
454 CONFIG_SYS_VXWORKS_BOOT_ADDR - Address of boot parameters
456 CONFIG_SYS_VXWORKS_ADD_PARAMS
458 Add it at the end of the bootline. E.g "u=username pw=secret"
460 Note: If a "bootargs" environment is defined, it will overwride
461 the defaults discussed just above.
466 Define this if you want support for Amba PrimeCell PL010 UARTs.
470 Define this if you want support for Amba PrimeCell PL011 UARTs.
474 If you have Amba PrimeCell PL011 UARTs, set this variable to
475 the clock speed of the UARTs.
479 If you have Amba PrimeCell PL010 or PL011 UARTs on your board,
480 define this to a list of base addresses for each (supported)
481 port. See e.g. include/configs/versatile.h
483 CONFIG_PL011_SERIAL_RLCR
485 Some vendor versions of PL011 serial ports (e.g. ST-Ericsson U8500)
486 have separate receive and transmit line control registers. Set
487 this variable to initialize the extra register.
489 CONFIG_PL011_SERIAL_FLUSH_ON_INIT
491 On some platforms (e.g. U8500) U-Boot is loaded by a second stage
492 boot loader that has already initialized the UART. Define this
493 variable to flush the UART at init time.
497 Depending on board, define exactly one serial port
498 (like CONFIG_8xx_CONS_SMC1, CONFIG_8xx_CONS_SMC2,
499 CONFIG_8xx_CONS_SCC1, ...), or switch off the serial
500 console by defining CONFIG_8xx_CONS_NONE
502 Note: if CONFIG_8xx_CONS_NONE is defined, the serial
503 port routines must be defined elsewhere
504 (i.e. serial_init(), serial_getc(), ...)
507 Enables console device for a color framebuffer. Needs following
508 defines (cf. smiLynxEM, i8042, board/eltec/bab7xx)
509 VIDEO_FB_LITTLE_ENDIAN graphic memory organisation
511 VIDEO_HW_RECTFILL graphic chip supports
514 VIDEO_HW_BITBLT graphic chip supports
515 bit-blit (cf. smiLynxEM)
516 VIDEO_VISIBLE_COLS visible pixel columns
518 VIDEO_VISIBLE_ROWS visible pixel rows
519 VIDEO_PIXEL_SIZE bytes per pixel
520 VIDEO_DATA_FORMAT graphic data format
521 (0-5, cf. cfb_console.c)
522 VIDEO_FB_ADRS framebuffer address
523 VIDEO_KBD_INIT_FCT keyboard int fct
524 (i.e. i8042_kbd_init())
525 VIDEO_TSTC_FCT test char fct
527 VIDEO_GETC_FCT get char fct
529 CONFIG_CONSOLE_CURSOR cursor drawing on/off
530 (requires blink timer
532 CONFIG_SYS_CONSOLE_BLINK_COUNT blink interval (cf. i8042.c)
533 CONFIG_CONSOLE_TIME display time/date info in
535 (requires CONFIG_CMD_DATE)
536 CONFIG_VIDEO_LOGO display Linux logo in
538 CONFIG_VIDEO_BMP_LOGO use bmp_logo.h instead of
539 linux_logo.h for logo.
540 Requires CONFIG_VIDEO_LOGO
541 CONFIG_CONSOLE_EXTRA_INFO
542 additional board info beside
545 When CONFIG_CFB_CONSOLE is defined, video console is
546 default i/o. Serial console can be forced with
547 environment 'console=serial'.
549 When CONFIG_SILENT_CONSOLE is defined, all console
550 messages (by U-Boot and Linux!) can be silenced with
551 the "silent" environment variable. See
552 doc/README.silent for more information.
555 CONFIG_BAUDRATE - in bps
556 Select one of the baudrates listed in
557 CONFIG_SYS_BAUDRATE_TABLE, see below.
558 CONFIG_SYS_BRGCLK_PRESCALE, baudrate prescale
560 - Console Rx buffer length
561 With CONFIG_SYS_SMC_RXBUFLEN it is possible to define
562 the maximum receive buffer length for the SMC.
563 This option is actual only for 82xx and 8xx possible.
564 If using CONFIG_SYS_SMC_RXBUFLEN also CONFIG_SYS_MAXIDLE
565 must be defined, to setup the maximum idle timeout for
568 - Boot Delay: CONFIG_BOOTDELAY - in seconds
569 Delay before automatically booting the default image;
570 set to -1 to disable autoboot.
572 See doc/README.autoboot for these options that
573 work with CONFIG_BOOTDELAY. None are required.
574 CONFIG_BOOT_RETRY_TIME
575 CONFIG_BOOT_RETRY_MIN
576 CONFIG_AUTOBOOT_KEYED
577 CONFIG_AUTOBOOT_PROMPT
578 CONFIG_AUTOBOOT_DELAY_STR
579 CONFIG_AUTOBOOT_STOP_STR
580 CONFIG_AUTOBOOT_DELAY_STR2
581 CONFIG_AUTOBOOT_STOP_STR2
582 CONFIG_ZERO_BOOTDELAY_CHECK
583 CONFIG_RESET_TO_RETRY
587 Only needed when CONFIG_BOOTDELAY is enabled;
588 define a command string that is automatically executed
589 when no character is read on the console interface
590 within "Boot Delay" after reset.
593 This can be used to pass arguments to the bootm
594 command. The value of CONFIG_BOOTARGS goes into the
595 environment value "bootargs".
597 CONFIG_RAMBOOT and CONFIG_NFSBOOT
598 The value of these goes into the environment as
599 "ramboot" and "nfsboot" respectively, and can be used
600 as a convenience, when switching between booting from
606 When this option is #defined, the existence of the
607 environment variable "preboot" will be checked
608 immediately before starting the CONFIG_BOOTDELAY
609 countdown and/or running the auto-boot command resp.
610 entering interactive mode.
612 This feature is especially useful when "preboot" is
613 automatically generated or modified. For an example
614 see the LWMON board specific code: here "preboot" is
615 modified when the user holds down a certain
616 combination of keys on the (special) keyboard when
619 - Serial Download Echo Mode:
621 If defined to 1, all characters received during a
622 serial download (using the "loads" command) are
623 echoed back. This might be needed by some terminal
624 emulations (like "cu"), but may as well just take
625 time on others. This setting #define's the initial
626 value of the "loads_echo" environment variable.
628 - Kgdb Serial Baudrate: (if CONFIG_CMD_KGDB is defined)
630 Select one of the baudrates listed in
631 CONFIG_SYS_BAUDRATE_TABLE, see below.
634 Monitor commands can be included or excluded
635 from the build by using the #include files
636 "config_cmd_all.h" and #undef'ing unwanted
637 commands, or using "config_cmd_default.h"
638 and augmenting with additional #define's
641 The default command configuration includes all commands
642 except those marked below with a "*".
644 CONFIG_CMD_ASKENV * ask for env variable
645 CONFIG_CMD_BDI bdinfo
646 CONFIG_CMD_BEDBUG * Include BedBug Debugger
647 CONFIG_CMD_BMP * BMP support
648 CONFIG_CMD_BSP * Board specific commands
649 CONFIG_CMD_BOOTD bootd
650 CONFIG_CMD_CACHE * icache, dcache
651 CONFIG_CMD_CONSOLE coninfo
652 CONFIG_CMD_CRC32 * crc32
653 CONFIG_CMD_DATE * support for RTC, date/time...
654 CONFIG_CMD_DHCP * DHCP support
655 CONFIG_CMD_DIAG * Diagnostics
656 CONFIG_CMD_DS4510 * ds4510 I2C gpio commands
657 CONFIG_CMD_DS4510_INFO * ds4510 I2C info command
658 CONFIG_CMD_DS4510_MEM * ds4510 I2C eeprom/sram commansd
659 CONFIG_CMD_DS4510_RST * ds4510 I2C rst command
660 CONFIG_CMD_DTT * Digital Therm and Thermostat
661 CONFIG_CMD_ECHO echo arguments
662 CONFIG_CMD_EDITENV edit env variable
663 CONFIG_CMD_EEPROM * EEPROM read/write support
664 CONFIG_CMD_ELF * bootelf, bootvx
665 CONFIG_CMD_EXPORTENV * export the environment
666 CONFIG_CMD_SAVEENV saveenv
667 CONFIG_CMD_FDC * Floppy Disk Support
668 CONFIG_CMD_FAT * FAT partition support
669 CONFIG_CMD_FDOS * Dos diskette Support
670 CONFIG_CMD_FLASH flinfo, erase, protect
671 CONFIG_CMD_FPGA FPGA device initialization support
672 CONFIG_CMD_GO * the 'go' command (exec code)
673 CONFIG_CMD_GREPENV * search environment
674 CONFIG_CMD_HWFLOW * RTS/CTS hw flow control
675 CONFIG_CMD_I2C * I2C serial bus support
676 CONFIG_CMD_IDE * IDE harddisk support
677 CONFIG_CMD_IMI iminfo
678 CONFIG_CMD_IMLS List all found images
679 CONFIG_CMD_IMMAP * IMMR dump support
680 CONFIG_CMD_IMPORTENV * import an environment
681 CONFIG_CMD_IRQ * irqinfo
682 CONFIG_CMD_ITEST Integer/string test of 2 values
683 CONFIG_CMD_JFFS2 * JFFS2 Support
684 CONFIG_CMD_KGDB * kgdb
685 CONFIG_CMD_LDRINFO ldrinfo (display Blackfin loader)
686 CONFIG_CMD_LOADB loadb
687 CONFIG_CMD_LOADS loads
688 CONFIG_CMD_MD5SUM print md5 message digest
689 (requires CONFIG_CMD_MEMORY and CONFIG_MD5)
690 CONFIG_CMD_MEMORY md, mm, nm, mw, cp, cmp, crc, base,
692 CONFIG_CMD_MISC Misc functions like sleep etc
693 CONFIG_CMD_MMC * MMC memory mapped support
694 CONFIG_CMD_MII * MII utility commands
695 CONFIG_CMD_MTDPARTS * MTD partition support
696 CONFIG_CMD_NAND * NAND support
697 CONFIG_CMD_NET bootp, tftpboot, rarpboot
698 CONFIG_CMD_PCA953X * PCA953x I2C gpio commands
699 CONFIG_CMD_PCA953X_INFO * PCA953x I2C gpio info command
700 CONFIG_CMD_PCI * pciinfo
701 CONFIG_CMD_PCMCIA * PCMCIA support
702 CONFIG_CMD_PING * send ICMP ECHO_REQUEST to network
704 CONFIG_CMD_PORTIO * Port I/O
705 CONFIG_CMD_REGINFO * Register dump
706 CONFIG_CMD_RUN run command in env variable
707 CONFIG_CMD_SAVES * save S record dump
708 CONFIG_CMD_SCSI * SCSI Support
709 CONFIG_CMD_SDRAM * print SDRAM configuration information
710 (requires CONFIG_CMD_I2C)
711 CONFIG_CMD_SETGETDCR Support for DCR Register access
713 CONFIG_CMD_SHA1SUM print sha1 memory digest
714 (requires CONFIG_CMD_MEMORY)
715 CONFIG_CMD_SOURCE "source" command Support
716 CONFIG_CMD_SPI * SPI serial bus support
717 CONFIG_CMD_TFTPSRV * TFTP transfer in server mode
718 CONFIG_CMD_USB * USB support
719 CONFIG_CMD_CDP * Cisco Discover Protocol support
720 CONFIG_CMD_FSL * Microblaze FSL support
723 EXAMPLE: If you want all functions except of network
724 support you can write:
726 #include "config_cmd_all.h"
727 #undef CONFIG_CMD_NET
730 fdt (flattened device tree) command: CONFIG_OF_LIBFDT
732 Note: Don't enable the "icache" and "dcache" commands
733 (configuration option CONFIG_CMD_CACHE) unless you know
734 what you (and your U-Boot users) are doing. Data
735 cache cannot be enabled on systems like the 8xx or
736 8260 (where accesses to the IMMR region must be
737 uncached), and it cannot be disabled on all other
738 systems where we (mis-) use the data cache to hold an
739 initial stack and some data.
742 XXX - this list needs to get updated!
746 If this variable is defined, it enables watchdog
747 support for the SoC. There must be support in the SoC
748 specific code for a watchdog. For the 8xx and 8260
749 CPUs, the SIU Watchdog feature is enabled in the SYPCR
750 register. When supported for a specific SoC is
751 available, then no further board specific code should
755 When using a watchdog circuitry external to the used
756 SoC, then define this variable and provide board
757 specific code for the "hw_watchdog_reset" function.
760 CONFIG_VERSION_VARIABLE
761 If this variable is defined, an environment variable
762 named "ver" is created by U-Boot showing the U-Boot
763 version as printed by the "version" command.
764 This variable is readonly.
768 When CONFIG_CMD_DATE is selected, the type of the RTC
769 has to be selected, too. Define exactly one of the
772 CONFIG_RTC_MPC8xx - use internal RTC of MPC8xx
773 CONFIG_RTC_PCF8563 - use Philips PCF8563 RTC
774 CONFIG_RTC_MC13783 - use MC13783 RTC
775 CONFIG_RTC_MC146818 - use MC146818 RTC
776 CONFIG_RTC_DS1307 - use Maxim, Inc. DS1307 RTC
777 CONFIG_RTC_DS1337 - use Maxim, Inc. DS1337 RTC
778 CONFIG_RTC_DS1338 - use Maxim, Inc. DS1338 RTC
779 CONFIG_RTC_DS164x - use Dallas DS164x RTC
780 CONFIG_RTC_ISL1208 - use Intersil ISL1208 RTC
781 CONFIG_RTC_MAX6900 - use Maxim, Inc. MAX6900 RTC
782 CONFIG_SYS_RTC_DS1337_NOOSC - Turn off the OSC output for DS1337
783 CONFIG_SYS_RV3029_TCR - enable trickle charger on
786 Note that if the RTC uses I2C, then the I2C interface
787 must also be configured. See I2C Support, below.
790 CONFIG_PCA953X - use NXP's PCA953X series I2C GPIO
791 CONFIG_PCA953X_INFO - enable pca953x info command
793 The CONFIG_SYS_I2C_PCA953X_WIDTH option specifies a list of
794 chip-ngpio pairs that tell the PCA953X driver the number of
795 pins supported by a particular chip.
797 Note that if the GPIO device uses I2C, then the I2C interface
798 must also be configured. See I2C Support, below.
802 When CONFIG_TIMESTAMP is selected, the timestamp
803 (date and time) of an image is printed by image
804 commands like bootm or iminfo. This option is
805 automatically enabled when you select CONFIG_CMD_DATE .
808 CONFIG_MAC_PARTITION and/or CONFIG_DOS_PARTITION
809 and/or CONFIG_ISO_PARTITION and/or CONFIG_EFI_PARTITION
811 If IDE or SCSI support is enabled (CONFIG_CMD_IDE or
812 CONFIG_CMD_SCSI) you must configure support for at
813 least one partition type as well.
816 CONFIG_IDE_RESET_ROUTINE - this is defined in several
817 board configurations files but used nowhere!
819 CONFIG_IDE_RESET - is this is defined, IDE Reset will
820 be performed by calling the function
821 ide_set_reset(int reset)
822 which has to be defined in a board specific file
827 Set this to enable ATAPI support.
832 Set this to enable support for disks larger than 137GB
833 Also look at CONFIG_SYS_64BIT_LBA.
834 Whithout these , LBA48 support uses 32bit variables and will 'only'
835 support disks up to 2.1TB.
837 CONFIG_SYS_64BIT_LBA:
838 When enabled, makes the IDE subsystem use 64bit sector addresses.
842 At the moment only there is only support for the
843 SYM53C8XX SCSI controller; define
844 CONFIG_SCSI_SYM53C8XX to enable it.
846 CONFIG_SYS_SCSI_MAX_LUN [8], CONFIG_SYS_SCSI_MAX_SCSI_ID [7] and
847 CONFIG_SYS_SCSI_MAX_DEVICE [CONFIG_SYS_SCSI_MAX_SCSI_ID *
848 CONFIG_SYS_SCSI_MAX_LUN] can be adjusted to define the
849 maximum numbers of LUNs, SCSI ID's and target
851 CONFIG_SYS_SCSI_SYM53C8XX_CCF to fix clock timing (80Mhz)
853 - NETWORK Support (PCI):
855 Support for Intel 8254x gigabit chips.
857 CONFIG_E1000_FALLBACK_MAC
858 default MAC for empty EEPROM after production.
861 Support for Intel 82557/82559/82559ER chips.
862 Optional CONFIG_EEPRO100_SROM_WRITE enables EEPROM
863 write routine for first time initialisation.
866 Support for Digital 2114x chips.
867 Optional CONFIG_TULIP_SELECT_MEDIA for board specific
868 modem chip initialisation (KS8761/QS6611).
871 Support for National dp83815 chips.
874 Support for National dp8382[01] gigabit chips.
876 - NETWORK Support (other):
878 CONFIG_DRIVER_AT91EMAC
879 Support for AT91RM9200 EMAC.
882 Define this to use reduced MII inteface
884 CONFIG_DRIVER_AT91EMAC_QUIET
885 If this defined, the driver is quiet.
886 The driver doen't show link status messages.
888 CONFIG_DRIVER_LAN91C96
889 Support for SMSC's LAN91C96 chips.
892 Define this to hold the physical address
893 of the LAN91C96's I/O space
895 CONFIG_LAN91C96_USE_32_BIT
896 Define this to enable 32 bit addressing
898 CONFIG_DRIVER_SMC91111
899 Support for SMSC's LAN91C111 chip
902 Define this to hold the physical address
903 of the device (I/O space)
905 CONFIG_SMC_USE_32_BIT
906 Define this if data bus is 32 bits
908 CONFIG_SMC_USE_IOFUNCS
909 Define this to use i/o functions instead of macros
910 (some hardware wont work with macros)
913 Support for Faraday's FTGMAC100 Gigabit SoC Ethernet
915 CONFIG_FTGMAC100_EGIGA
916 Define this to use GE link update with gigabit PHY.
917 Define this if FTGMAC100 is connected to gigabit PHY.
918 If your system has 10/100 PHY only, it might not occur
919 wrong behavior. Because PHY usually return timeout or
920 useless data when polling gigabit status and gigabit
921 control registers. This behavior won't affect the
922 correctnessof 10/100 link speed update.
925 Support for SMSC's LAN911x and LAN921x chips
928 Define this to hold the physical address
929 of the device (I/O space)
931 CONFIG_SMC911X_32_BIT
932 Define this if data bus is 32 bits
934 CONFIG_SMC911X_16_BIT
935 Define this if data bus is 16 bits. If your processor
936 automatically converts one 32 bit word to two 16 bit
937 words you may also try CONFIG_SMC911X_32_BIT.
940 Support for Renesas on-chip Ethernet controller
942 CONFIG_SH_ETHER_USE_PORT
943 Define the number of ports to be used
945 CONFIG_SH_ETHER_PHY_ADDR
946 Define the ETH PHY's address
948 CONFIG_SH_ETHER_CACHE_WRITEBACK
949 If this option is set, the driver enables cache flush.
952 At the moment only the UHCI host controller is
953 supported (PIP405, MIP405, MPC5200); define
954 CONFIG_USB_UHCI to enable it.
955 define CONFIG_USB_KEYBOARD to enable the USB Keyboard
956 and define CONFIG_USB_STORAGE to enable the USB
959 Supported are USB Keyboards and USB Floppy drives
961 MPC5200 USB requires additional defines:
963 for 528 MHz Clock: 0x0001bbbb
967 for differential drivers: 0x00001000
968 for single ended drivers: 0x00005000
969 for differential drivers on PSC3: 0x00000100
970 for single ended drivers on PSC3: 0x00004100
971 CONFIG_SYS_USB_EVENT_POLL
972 May be defined to allow interrupt polling
973 instead of using asynchronous interrupts
976 Define the below if you wish to use the USB console.
977 Once firmware is rebuilt from a serial console issue the
978 command "setenv stdin usbtty; setenv stdout usbtty" and
979 attach your USB cable. The Unix command "dmesg" should print
980 it has found a new device. The environment variable usbtty
981 can be set to gserial or cdc_acm to enable your device to
982 appear to a USB host as a Linux gserial device or a
983 Common Device Class Abstract Control Model serial device.
984 If you select usbtty = gserial you should be able to enumerate
986 # modprobe usbserial vendor=0xVendorID product=0xProductID
987 else if using cdc_acm, simply setting the environment
988 variable usbtty to be cdc_acm should suffice. The following
989 might be defined in YourBoardName.h
992 Define this to build a UDC device
995 Define this to have a tty type of device available to
996 talk to the UDC device
998 CONFIG_SYS_CONSOLE_IS_IN_ENV
999 Define this if you want stdin, stdout &/or stderr to
1003 CONFIG_SYS_USB_EXTC_CLK 0xBLAH
1004 Derive USB clock from external clock "blah"
1005 - CONFIG_SYS_USB_EXTC_CLK 0x02
1007 CONFIG_SYS_USB_BRG_CLK 0xBLAH
1008 Derive USB clock from brgclk
1009 - CONFIG_SYS_USB_BRG_CLK 0x04
1011 If you have a USB-IF assigned VendorID then you may wish to
1012 define your own vendor specific values either in BoardName.h
1013 or directly in usbd_vendor_info.h. If you don't define
1014 CONFIG_USBD_MANUFACTURER, CONFIG_USBD_PRODUCT_NAME,
1015 CONFIG_USBD_VENDORID and CONFIG_USBD_PRODUCTID, then U-Boot
1016 should pretend to be a Linux device to it's target host.
1018 CONFIG_USBD_MANUFACTURER
1019 Define this string as the name of your company for
1020 - CONFIG_USBD_MANUFACTURER "my company"
1022 CONFIG_USBD_PRODUCT_NAME
1023 Define this string as the name of your product
1024 - CONFIG_USBD_PRODUCT_NAME "acme usb device"
1026 CONFIG_USBD_VENDORID
1027 Define this as your assigned Vendor ID from the USB
1028 Implementors Forum. This *must* be a genuine Vendor ID
1029 to avoid polluting the USB namespace.
1030 - CONFIG_USBD_VENDORID 0xFFFF
1032 CONFIG_USBD_PRODUCTID
1033 Define this as the unique Product ID
1035 - CONFIG_USBD_PRODUCTID 0xFFFF
1039 The MMC controller on the Intel PXA is supported. To
1040 enable this define CONFIG_MMC. The MMC can be
1041 accessed from the boot prompt by mapping the device
1042 to physical memory similar to flash. Command line is
1043 enabled with CONFIG_CMD_MMC. The MMC driver also works with
1044 the FAT fs. This is enabled with CONFIG_CMD_FAT.
1046 - Journaling Flash filesystem support:
1047 CONFIG_JFFS2_NAND, CONFIG_JFFS2_NAND_OFF, CONFIG_JFFS2_NAND_SIZE,
1048 CONFIG_JFFS2_NAND_DEV
1049 Define these for a default partition on a NAND device
1051 CONFIG_SYS_JFFS2_FIRST_SECTOR,
1052 CONFIG_SYS_JFFS2_FIRST_BANK, CONFIG_SYS_JFFS2_NUM_BANKS
1053 Define these for a default partition on a NOR device
1055 CONFIG_SYS_JFFS_CUSTOM_PART
1056 Define this to create an own partition. You have to provide a
1057 function struct part_info* jffs2_part_info(int part_num)
1059 If you define only one JFFS2 partition you may also want to
1060 #define CONFIG_SYS_JFFS_SINGLE_PART 1
1061 to disable the command chpart. This is the default when you
1062 have not defined a custom partition
1067 Define this to enable standard (PC-Style) keyboard
1071 Standard PC keyboard driver with US (is default) and
1072 GERMAN key layout (switch via environment 'keymap=de') support.
1073 Export function i8042_kbd_init, i8042_tstc and i8042_getc
1074 for cfb_console. Supports cursor blinking.
1079 Define this to enable video support (for output to
1082 CONFIG_VIDEO_CT69000
1084 Enable Chips & Technologies 69000 Video chip
1086 CONFIG_VIDEO_SMI_LYNXEM
1087 Enable Silicon Motion SMI 712/710/810 Video chip. The
1088 video output is selected via environment 'videoout'
1089 (1 = LCD and 2 = CRT). If videoout is undefined, CRT is
1092 For the CT69000 and SMI_LYNXEM drivers, videomode is
1093 selected via environment 'videomode'. Two different ways
1095 - "videomode=num" 'num' is a standard LiLo mode numbers.
1096 Following standard modes are supported (* is default):
1098 Colors 640x480 800x600 1024x768 1152x864 1280x1024
1099 -------------+---------------------------------------------
1100 8 bits | 0x301* 0x303 0x305 0x161 0x307
1101 15 bits | 0x310 0x313 0x316 0x162 0x319
1102 16 bits | 0x311 0x314 0x317 0x163 0x31A
1103 24 bits | 0x312 0x315 0x318 ? 0x31B
1104 -------------+---------------------------------------------
1105 (i.e. setenv videomode 317; saveenv; reset;)
1107 - "videomode=bootargs" all the video parameters are parsed
1108 from the bootargs. (See drivers/video/videomodes.c)
1111 CONFIG_VIDEO_SED13806
1112 Enable Epson SED13806 driver. This driver supports 8bpp
1113 and 16bpp modes defined by CONFIG_VIDEO_SED13806_8BPP
1114 or CONFIG_VIDEO_SED13806_16BPP
1117 Enable the Freescale DIU video driver. Reference boards for
1118 SOCs that have a DIU should define this macro to enable DIU
1119 support, and should also define these other macros:
1125 CONFIG_VIDEO_SW_CURSOR
1126 CONFIG_VGA_AS_SINGLE_DEVICE
1128 CONFIG_VIDEO_BMP_LOGO
1130 The DIU driver will look for the 'video-mode' environment
1131 variable, and if defined, enable the DIU as a console during
1132 boot. See the documentation file README.video for a
1133 description of this variable.
1138 Define this to enable a custom keyboard support.
1139 This simply calls drv_keyboard_init() which must be
1140 defined in your board-specific files.
1141 The only board using this so far is RBC823.
1143 - LCD Support: CONFIG_LCD
1145 Define this to enable LCD support (for output to LCD
1146 display); also select one of the supported displays
1147 by defining one of these:
1151 HITACHI TX09D70VM1CCA, 3.5", 240x320.
1153 CONFIG_NEC_NL6448AC33:
1155 NEC NL6448AC33-18. Active, color, single scan.
1157 CONFIG_NEC_NL6448BC20
1159 NEC NL6448BC20-08. 6.5", 640x480.
1160 Active, color, single scan.
1162 CONFIG_NEC_NL6448BC33_54
1164 NEC NL6448BC33-54. 10.4", 640x480.
1165 Active, color, single scan.
1169 Sharp 320x240. Active, color, single scan.
1170 It isn't 16x9, and I am not sure what it is.
1172 CONFIG_SHARP_LQ64D341
1174 Sharp LQ64D341 display, 640x480.
1175 Active, color, single scan.
1179 HLD1045 display, 640x480.
1180 Active, color, single scan.
1184 Optrex CBL50840-2 NF-FW 99 22 M5
1186 Hitachi LMG6912RPFC-00T
1190 320x240. Black & white.
1192 Normally display is black on white background; define
1193 CONFIG_SYS_WHITE_ON_BLACK to get it inverted.
1195 - Splash Screen Support: CONFIG_SPLASH_SCREEN
1197 If this option is set, the environment is checked for
1198 a variable "splashimage". If found, the usual display
1199 of logo, copyright and system information on the LCD
1200 is suppressed and the BMP image at the address
1201 specified in "splashimage" is loaded instead. The
1202 console is redirected to the "nulldev", too. This
1203 allows for a "silent" boot where a splash screen is
1204 loaded very quickly after power-on.
1206 CONFIG_SPLASH_SCREEN_ALIGN
1208 If this option is set the splash image can be freely positioned
1209 on the screen. Environment variable "splashpos" specifies the
1210 position as "x,y". If a positive number is given it is used as
1211 number of pixel from left/top. If a negative number is given it
1212 is used as number of pixel from right/bottom. You can also
1213 specify 'm' for centering the image.
1216 setenv splashpos m,m
1217 => image at center of screen
1219 setenv splashpos 30,20
1220 => image at x = 30 and y = 20
1222 setenv splashpos -10,m
1223 => vertically centered image
1224 at x = dspWidth - bmpWidth - 9
1226 - Gzip compressed BMP image support: CONFIG_VIDEO_BMP_GZIP
1228 If this option is set, additionally to standard BMP
1229 images, gzipped BMP images can be displayed via the
1230 splashscreen support or the bmp command.
1232 - Run length encoded BMP image (RLE8) support: CONFIG_VIDEO_BMP_RLE8
1234 If this option is set, 8-bit RLE compressed BMP images
1235 can be displayed via the splashscreen support or the
1238 - Compression support:
1241 If this option is set, support for bzip2 compressed
1242 images is included. If not, only uncompressed and gzip
1243 compressed images are supported.
1245 NOTE: the bzip2 algorithm requires a lot of RAM, so
1246 the malloc area (as defined by CONFIG_SYS_MALLOC_LEN) should
1251 If this option is set, support for lzma compressed
1254 Note: The LZMA algorithm adds between 2 and 4KB of code and it
1255 requires an amount of dynamic memory that is given by the
1258 (1846 + 768 << (lc + lp)) * sizeof(uint16)
1260 Where lc and lp stand for, respectively, Literal context bits
1261 and Literal pos bits.
1263 This value is upper-bounded by 14MB in the worst case. Anyway,
1264 for a ~4MB large kernel image, we have lc=3 and lp=0 for a
1265 total amount of (1846 + 768 << (3 + 0)) * 2 = ~41KB... that is
1266 a very small buffer.
1268 Use the lzmainfo tool to determinate the lc and lp values and
1269 then calculate the amount of needed dynamic memory (ensuring
1270 the appropriate CONFIG_SYS_MALLOC_LEN value).
1275 The address of PHY on MII bus.
1277 CONFIG_PHY_CLOCK_FREQ (ppc4xx)
1279 The clock frequency of the MII bus
1283 If this option is set, support for speed/duplex
1284 detection of gigabit PHY is included.
1286 CONFIG_PHY_RESET_DELAY
1288 Some PHY like Intel LXT971A need extra delay after
1289 reset before any MII register access is possible.
1290 For such PHY, set this option to the usec delay
1291 required. (minimum 300usec for LXT971A)
1293 CONFIG_PHY_CMD_DELAY (ppc4xx)
1295 Some PHY like Intel LXT971A need extra delay after
1296 command issued before MII status register can be read
1306 Define a default value for Ethernet address to use
1307 for the respective Ethernet interface, in case this
1308 is not determined automatically.
1313 Define a default value for the IP address to use for
1314 the default Ethernet interface, in case this is not
1315 determined through e.g. bootp.
1317 - Server IP address:
1320 Defines a default value for the IP address of a TFTP
1321 server to contact when using the "tftboot" command.
1323 CONFIG_KEEP_SERVERADDR
1325 Keeps the server's MAC address, in the env 'serveraddr'
1326 for passing to bootargs (like Linux's netconsole option)
1328 - Multicast TFTP Mode:
1331 Defines whether you want to support multicast TFTP as per
1332 rfc-2090; for example to work with atftp. Lets lots of targets
1333 tftp down the same boot image concurrently. Note: the Ethernet
1334 driver in use must provide a function: mcast() to join/leave a
1337 - BOOTP Recovery Mode:
1338 CONFIG_BOOTP_RANDOM_DELAY
1340 If you have many targets in a network that try to
1341 boot using BOOTP, you may want to avoid that all
1342 systems send out BOOTP requests at precisely the same
1343 moment (which would happen for instance at recovery
1344 from a power failure, when all systems will try to
1345 boot, thus flooding the BOOTP server. Defining
1346 CONFIG_BOOTP_RANDOM_DELAY causes a random delay to be
1347 inserted before sending out BOOTP requests. The
1348 following delays are inserted then:
1350 1st BOOTP request: delay 0 ... 1 sec
1351 2nd BOOTP request: delay 0 ... 2 sec
1352 3rd BOOTP request: delay 0 ... 4 sec
1354 BOOTP requests: delay 0 ... 8 sec
1356 - DHCP Advanced Options:
1357 You can fine tune the DHCP functionality by defining
1358 CONFIG_BOOTP_* symbols:
1360 CONFIG_BOOTP_SUBNETMASK
1361 CONFIG_BOOTP_GATEWAY
1362 CONFIG_BOOTP_HOSTNAME
1363 CONFIG_BOOTP_NISDOMAIN
1364 CONFIG_BOOTP_BOOTPATH
1365 CONFIG_BOOTP_BOOTFILESIZE
1368 CONFIG_BOOTP_SEND_HOSTNAME
1369 CONFIG_BOOTP_NTPSERVER
1370 CONFIG_BOOTP_TIMEOFFSET
1371 CONFIG_BOOTP_VENDOREX
1373 CONFIG_BOOTP_SERVERIP - TFTP server will be the serverip
1374 environment variable, not the BOOTP server.
1376 CONFIG_BOOTP_DNS2 - If a DHCP client requests the DNS
1377 serverip from a DHCP server, it is possible that more
1378 than one DNS serverip is offered to the client.
1379 If CONFIG_BOOTP_DNS2 is enabled, the secondary DNS
1380 serverip will be stored in the additional environment
1381 variable "dnsip2". The first DNS serverip is always
1382 stored in the variable "dnsip", when CONFIG_BOOTP_DNS
1385 CONFIG_BOOTP_SEND_HOSTNAME - Some DHCP servers are capable
1386 to do a dynamic update of a DNS server. To do this, they
1387 need the hostname of the DHCP requester.
1388 If CONFIG_BOOTP_SEND_HOSTNAME is defined, the content
1389 of the "hostname" environment variable is passed as
1390 option 12 to the DHCP server.
1392 CONFIG_BOOTP_DHCP_REQUEST_DELAY
1394 A 32bit value in microseconds for a delay between
1395 receiving a "DHCP Offer" and sending the "DHCP Request".
1396 This fixes a problem with certain DHCP servers that don't
1397 respond 100% of the time to a "DHCP request". E.g. On an
1398 AT91RM9200 processor running at 180MHz, this delay needed
1399 to be *at least* 15,000 usec before a Windows Server 2003
1400 DHCP server would reply 100% of the time. I recommend at
1401 least 50,000 usec to be safe. The alternative is to hope
1402 that one of the retries will be successful but note that
1403 the DHCP timeout and retry process takes a longer than
1407 CONFIG_CDP_DEVICE_ID
1409 The device id used in CDP trigger frames.
1411 CONFIG_CDP_DEVICE_ID_PREFIX
1413 A two character string which is prefixed to the MAC address
1418 A printf format string which contains the ascii name of
1419 the port. Normally is set to "eth%d" which sets
1420 eth0 for the first Ethernet, eth1 for the second etc.
1422 CONFIG_CDP_CAPABILITIES
1424 A 32bit integer which indicates the device capabilities;
1425 0x00000010 for a normal host which does not forwards.
1429 An ascii string containing the version of the software.
1433 An ascii string containing the name of the platform.
1437 A 32bit integer sent on the trigger.
1439 CONFIG_CDP_POWER_CONSUMPTION
1441 A 16bit integer containing the power consumption of the
1442 device in .1 of milliwatts.
1444 CONFIG_CDP_APPLIANCE_VLAN_TYPE
1446 A byte containing the id of the VLAN.
1448 - Status LED: CONFIG_STATUS_LED
1450 Several configurations allow to display the current
1451 status using a LED. For instance, the LED will blink
1452 fast while running U-Boot code, stop blinking as
1453 soon as a reply to a BOOTP request was received, and
1454 start blinking slow once the Linux kernel is running
1455 (supported by a status LED driver in the Linux
1456 kernel). Defining CONFIG_STATUS_LED enables this
1459 - CAN Support: CONFIG_CAN_DRIVER
1461 Defining CONFIG_CAN_DRIVER enables CAN driver support
1462 on those systems that support this (optional)
1463 feature, like the TQM8xxL modules.
1465 - I2C Support: CONFIG_HARD_I2C | CONFIG_SOFT_I2C
1467 These enable I2C serial bus commands. Defining either of
1468 (but not both of) CONFIG_HARD_I2C or CONFIG_SOFT_I2C will
1469 include the appropriate I2C driver for the selected CPU.
1471 This will allow you to use i2c commands at the u-boot
1472 command line (as long as you set CONFIG_CMD_I2C in
1473 CONFIG_COMMANDS) and communicate with i2c based realtime
1474 clock chips. See common/cmd_i2c.c for a description of the
1475 command line interface.
1477 CONFIG_HARD_I2C selects a hardware I2C controller.
1479 CONFIG_SOFT_I2C configures u-boot to use a software (aka
1480 bit-banging) driver instead of CPM or similar hardware
1483 There are several other quantities that must also be
1484 defined when you define CONFIG_HARD_I2C or CONFIG_SOFT_I2C.
1486 In both cases you will need to define CONFIG_SYS_I2C_SPEED
1487 to be the frequency (in Hz) at which you wish your i2c bus
1488 to run and CONFIG_SYS_I2C_SLAVE to be the address of this node (ie
1489 the CPU's i2c node address).
1491 Now, the u-boot i2c code for the mpc8xx
1492 (arch/powerpc/cpu/mpc8xx/i2c.c) sets the CPU up as a master node
1493 and so its address should therefore be cleared to 0 (See,
1494 eg, MPC823e User's Manual p.16-473). So, set
1495 CONFIG_SYS_I2C_SLAVE to 0.
1497 CONFIG_SYS_I2C_INIT_MPC5XXX
1499 When a board is reset during an i2c bus transfer
1500 chips might think that the current transfer is still
1501 in progress. Reset the slave devices by sending start
1502 commands until the slave device responds.
1504 That's all that's required for CONFIG_HARD_I2C.
1506 If you use the software i2c interface (CONFIG_SOFT_I2C)
1507 then the following macros need to be defined (examples are
1508 from include/configs/lwmon.h):
1512 (Optional). Any commands necessary to enable the I2C
1513 controller or configure ports.
1515 eg: #define I2C_INIT (immr->im_cpm.cp_pbdir |= PB_SCL)
1519 (Only for MPC8260 CPU). The I/O port to use (the code
1520 assumes both bits are on the same port). Valid values
1521 are 0..3 for ports A..D.
1525 The code necessary to make the I2C data line active
1526 (driven). If the data line is open collector, this
1529 eg: #define I2C_ACTIVE (immr->im_cpm.cp_pbdir |= PB_SDA)
1533 The code necessary to make the I2C data line tri-stated
1534 (inactive). If the data line is open collector, this
1537 eg: #define I2C_TRISTATE (immr->im_cpm.cp_pbdir &= ~PB_SDA)
1541 Code that returns TRUE if the I2C data line is high,
1544 eg: #define I2C_READ ((immr->im_cpm.cp_pbdat & PB_SDA) != 0)
1548 If <bit> is TRUE, sets the I2C data line high. If it
1549 is FALSE, it clears it (low).
1551 eg: #define I2C_SDA(bit) \
1552 if(bit) immr->im_cpm.cp_pbdat |= PB_SDA; \
1553 else immr->im_cpm.cp_pbdat &= ~PB_SDA
1557 If <bit> is TRUE, sets the I2C clock line high. If it
1558 is FALSE, it clears it (low).
1560 eg: #define I2C_SCL(bit) \
1561 if(bit) immr->im_cpm.cp_pbdat |= PB_SCL; \
1562 else immr->im_cpm.cp_pbdat &= ~PB_SCL
1566 This delay is invoked four times per clock cycle so this
1567 controls the rate of data transfer. The data rate thus
1568 is 1 / (I2C_DELAY * 4). Often defined to be something
1571 #define I2C_DELAY udelay(2)
1573 CONFIG_SOFT_I2C_GPIO_SCL / CONFIG_SOFT_I2C_GPIO_SDA
1575 If your arch supports the generic GPIO framework (asm/gpio.h),
1576 then you may alternatively define the two GPIOs that are to be
1577 used as SCL / SDA. Any of the previous I2C_xxx macros will
1578 have GPIO-based defaults assigned to them as appropriate.
1580 You should define these to the GPIO value as given directly to
1581 the generic GPIO functions.
1583 CONFIG_SYS_I2C_INIT_BOARD
1585 When a board is reset during an i2c bus transfer
1586 chips might think that the current transfer is still
1587 in progress. On some boards it is possible to access
1588 the i2c SCLK line directly, either by using the
1589 processor pin as a GPIO or by having a second pin
1590 connected to the bus. If this option is defined a
1591 custom i2c_init_board() routine in boards/xxx/board.c
1592 is run early in the boot sequence.
1594 CONFIG_SYS_I2C_BOARD_LATE_INIT
1596 An alternative to CONFIG_SYS_I2C_INIT_BOARD. If this option is
1597 defined a custom i2c_board_late_init() routine in
1598 boards/xxx/board.c is run AFTER the operations in i2c_init()
1599 is completed. This callpoint can be used to unreset i2c bus
1600 using CPU i2c controller register accesses for CPUs whose i2c
1601 controller provide such a method. It is called at the end of
1602 i2c_init() to allow i2c_init operations to setup the i2c bus
1603 controller on the CPU (e.g. setting bus speed & slave address).
1605 CONFIG_I2CFAST (PPC405GP|PPC405EP only)
1607 This option enables configuration of bi_iic_fast[] flags
1608 in u-boot bd_info structure based on u-boot environment
1609 variable "i2cfast". (see also i2cfast)
1611 CONFIG_I2C_MULTI_BUS
1613 This option allows the use of multiple I2C buses, each of which
1614 must have a controller. At any point in time, only one bus is
1615 active. To switch to a different bus, use the 'i2c dev' command.
1616 Note that bus numbering is zero-based.
1618 CONFIG_SYS_I2C_NOPROBES
1620 This option specifies a list of I2C devices that will be skipped
1621 when the 'i2c probe' command is issued. If CONFIG_I2C_MULTI_BUS
1622 is set, specify a list of bus-device pairs. Otherwise, specify
1623 a 1D array of device addresses
1626 #undef CONFIG_I2C_MULTI_BUS
1627 #define CONFIG_SYS_I2C_NOPROBES {0x50,0x68}
1629 will skip addresses 0x50 and 0x68 on a board with one I2C bus
1631 #define CONFIG_I2C_MULTI_BUS
1632 #define CONFIG_SYS_I2C_MULTI_NOPROBES {{0,0x50},{0,0x68},{1,0x54}}
1634 will skip addresses 0x50 and 0x68 on bus 0 and address 0x54 on bus 1
1636 CONFIG_SYS_SPD_BUS_NUM
1638 If defined, then this indicates the I2C bus number for DDR SPD.
1639 If not defined, then U-Boot assumes that SPD is on I2C bus 0.
1641 CONFIG_SYS_RTC_BUS_NUM
1643 If defined, then this indicates the I2C bus number for the RTC.
1644 If not defined, then U-Boot assumes that RTC is on I2C bus 0.
1646 CONFIG_SYS_DTT_BUS_NUM
1648 If defined, then this indicates the I2C bus number for the DTT.
1649 If not defined, then U-Boot assumes that DTT is on I2C bus 0.
1651 CONFIG_SYS_I2C_DTT_ADDR:
1653 If defined, specifies the I2C address of the DTT device.
1654 If not defined, then U-Boot uses predefined value for
1655 specified DTT device.
1659 Define this option if you want to use Freescale's I2C driver in
1660 drivers/i2c/fsl_i2c.c.
1664 Define this option if you have I2C devices reached over 1 .. n
1665 I2C Muxes like the pca9544a. This option addes a new I2C
1666 Command "i2c bus [muxtype:muxaddr:muxchannel]" which adds a
1667 new I2C Bus to the existing I2C Busses. If you select the
1668 new Bus with "i2c dev", u-bbot sends first the commandos for
1669 the muxes to activate this new "bus".
1671 CONFIG_I2C_MULTI_BUS must be also defined, to use this
1675 Adding a new I2C Bus reached over 2 pca9544a muxes
1676 The First mux with address 70 and channel 6
1677 The Second mux with address 71 and channel 4
1679 => i2c bus pca9544a:70:6:pca9544a:71:4
1681 Use the "i2c bus" command without parameter, to get a list
1682 of I2C Busses with muxes:
1685 Busses reached over muxes:
1687 reached over Mux(es):
1690 reached over Mux(es):
1695 If you now switch to the new I2C Bus 3 with "i2c dev 3"
1696 u-boot sends First the Commando to the mux@70 to enable
1697 channel 6, and then the Commando to the mux@71 to enable
1700 After that, you can use the "normal" i2c commands as
1701 usual, to communicate with your I2C devices behind
1704 This option is actually implemented for the bitbanging
1705 algorithm in common/soft_i2c.c and for the Hardware I2C
1706 Bus on the MPC8260. But it should be not so difficult
1707 to add this option to other architectures.
1709 CONFIG_SOFT_I2C_READ_REPEATED_START
1711 defining this will force the i2c_read() function in
1712 the soft_i2c driver to perform an I2C repeated start
1713 between writing the address pointer and reading the
1714 data. If this define is omitted the default behaviour
1715 of doing a stop-start sequence will be used. Most I2C
1716 devices can use either method, but some require one or
1719 - SPI Support: CONFIG_SPI
1721 Enables SPI driver (so far only tested with
1722 SPI EEPROM, also an instance works with Crystal A/D and
1723 D/As on the SACSng board)
1727 Enables the driver for SPI controller on SuperH. Currently
1728 only SH7757 is supported.
1732 Enables extended (16-bit) SPI EEPROM addressing.
1733 (symmetrical to CONFIG_I2C_X)
1737 Enables a software (bit-bang) SPI driver rather than
1738 using hardware support. This is a general purpose
1739 driver that only requires three general I/O port pins
1740 (two outputs, one input) to function. If this is
1741 defined, the board configuration must define several
1742 SPI configuration items (port pins to use, etc). For
1743 an example, see include/configs/sacsng.h.
1747 Enables a hardware SPI driver for general-purpose reads
1748 and writes. As with CONFIG_SOFT_SPI, the board configuration
1749 must define a list of chip-select function pointers.
1750 Currently supported on some MPC8xxx processors. For an
1751 example, see include/configs/mpc8349emds.h.
1755 Enables the driver for the SPI controllers on i.MX and MXC
1756 SoCs. Currently only i.MX31 is supported.
1758 - FPGA Support: CONFIG_FPGA
1760 Enables FPGA subsystem.
1762 CONFIG_FPGA_<vendor>
1764 Enables support for specific chip vendors.
1767 CONFIG_FPGA_<family>
1769 Enables support for FPGA family.
1770 (SPARTAN2, SPARTAN3, VIRTEX2, CYCLONE2, ACEX1K, ACEX)
1774 Specify the number of FPGA devices to support.
1776 CONFIG_SYS_FPGA_PROG_FEEDBACK
1778 Enable printing of hash marks during FPGA configuration.
1780 CONFIG_SYS_FPGA_CHECK_BUSY
1782 Enable checks on FPGA configuration interface busy
1783 status by the configuration function. This option
1784 will require a board or device specific function to
1789 If defined, a function that provides delays in the FPGA
1790 configuration driver.
1792 CONFIG_SYS_FPGA_CHECK_CTRLC
1793 Allow Control-C to interrupt FPGA configuration
1795 CONFIG_SYS_FPGA_CHECK_ERROR
1797 Check for configuration errors during FPGA bitfile
1798 loading. For example, abort during Virtex II
1799 configuration if the INIT_B line goes low (which
1800 indicated a CRC error).
1802 CONFIG_SYS_FPGA_WAIT_INIT
1804 Maximum time to wait for the INIT_B line to deassert
1805 after PROB_B has been deasserted during a Virtex II
1806 FPGA configuration sequence. The default time is 500
1809 CONFIG_SYS_FPGA_WAIT_BUSY
1811 Maximum time to wait for BUSY to deassert during
1812 Virtex II FPGA configuration. The default is 5 ms.
1814 CONFIG_SYS_FPGA_WAIT_CONFIG
1816 Time to wait after FPGA configuration. The default is
1819 - Configuration Management:
1822 If defined, this string will be added to the U-Boot
1823 version information (U_BOOT_VERSION)
1825 - Vendor Parameter Protection:
1827 U-Boot considers the values of the environment
1828 variables "serial#" (Board Serial Number) and
1829 "ethaddr" (Ethernet Address) to be parameters that
1830 are set once by the board vendor / manufacturer, and
1831 protects these variables from casual modification by
1832 the user. Once set, these variables are read-only,
1833 and write or delete attempts are rejected. You can
1834 change this behaviour:
1836 If CONFIG_ENV_OVERWRITE is #defined in your config
1837 file, the write protection for vendor parameters is
1838 completely disabled. Anybody can change or delete
1841 Alternatively, if you #define _both_ CONFIG_ETHADDR
1842 _and_ CONFIG_OVERWRITE_ETHADDR_ONCE, a default
1843 Ethernet address is installed in the environment,
1844 which can be changed exactly ONCE by the user. [The
1845 serial# is unaffected by this, i. e. it remains
1851 Define this variable to enable the reservation of
1852 "protected RAM", i. e. RAM which is not overwritten
1853 by U-Boot. Define CONFIG_PRAM to hold the number of
1854 kB you want to reserve for pRAM. You can overwrite
1855 this default value by defining an environment
1856 variable "pram" to the number of kB you want to
1857 reserve. Note that the board info structure will
1858 still show the full amount of RAM. If pRAM is
1859 reserved, a new environment variable "mem" will
1860 automatically be defined to hold the amount of
1861 remaining RAM in a form that can be passed as boot
1862 argument to Linux, for instance like that:
1864 setenv bootargs ... mem=\${mem}
1867 This way you can tell Linux not to use this memory,
1868 either, which results in a memory region that will
1869 not be affected by reboots.
1871 *WARNING* If your board configuration uses automatic
1872 detection of the RAM size, you must make sure that
1873 this memory test is non-destructive. So far, the
1874 following board configurations are known to be
1877 ETX094, IVMS8, IVML24, SPD8xx, TQM8xxL,
1878 HERMES, IP860, RPXlite, LWMON, LANTEC,
1884 Define this variable to stop the system in case of a
1885 fatal error, so that you have to reset it manually.
1886 This is probably NOT a good idea for an embedded
1887 system where you want the system to reboot
1888 automatically as fast as possible, but it may be
1889 useful during development since you can try to debug
1890 the conditions that lead to the situation.
1892 CONFIG_NET_RETRY_COUNT
1894 This variable defines the number of retries for
1895 network operations like ARP, RARP, TFTP, or BOOTP
1896 before giving up the operation. If not defined, a
1897 default value of 5 is used.
1901 Timeout waiting for an ARP reply in milliseconds.
1903 - Command Interpreter:
1904 CONFIG_AUTO_COMPLETE
1906 Enable auto completion of commands using TAB.
1908 Note that this feature has NOT been implemented yet
1909 for the "hush" shell.
1912 CONFIG_SYS_HUSH_PARSER
1914 Define this variable to enable the "hush" shell (from
1915 Busybox) as command line interpreter, thus enabling
1916 powerful command line syntax like
1917 if...then...else...fi conditionals or `&&' and '||'
1918 constructs ("shell scripts").
1920 If undefined, you get the old, much simpler behaviour
1921 with a somewhat smaller memory footprint.
1924 CONFIG_SYS_PROMPT_HUSH_PS2
1926 This defines the secondary prompt string, which is
1927 printed when the command interpreter needs more input
1928 to complete a command. Usually "> ".
1932 In the current implementation, the local variables
1933 space and global environment variables space are
1934 separated. Local variables are those you define by
1935 simply typing `name=value'. To access a local
1936 variable later on, you have write `$name' or
1937 `${name}'; to execute the contents of a variable
1938 directly type `$name' at the command prompt.
1940 Global environment variables are those you use
1941 setenv/printenv to work with. To run a command stored
1942 in such a variable, you need to use the run command,
1943 and you must not use the '$' sign to access them.
1945 To store commands and special characters in a
1946 variable, please use double quotation marks
1947 surrounding the whole text of the variable, instead
1948 of the backslashes before semicolons and special
1951 - Commandline Editing and History:
1952 CONFIG_CMDLINE_EDITING
1954 Enable editing and History functions for interactive
1955 commandline input operations
1957 - Default Environment:
1958 CONFIG_EXTRA_ENV_SETTINGS
1960 Define this to contain any number of null terminated
1961 strings (variable = value pairs) that will be part of
1962 the default environment compiled into the boot image.
1964 For example, place something like this in your
1965 board's config file:
1967 #define CONFIG_EXTRA_ENV_SETTINGS \
1971 Warning: This method is based on knowledge about the
1972 internal format how the environment is stored by the
1973 U-Boot code. This is NOT an official, exported
1974 interface! Although it is unlikely that this format
1975 will change soon, there is no guarantee either.
1976 You better know what you are doing here.
1978 Note: overly (ab)use of the default environment is
1979 discouraged. Make sure to check other ways to preset
1980 the environment like the "source" command or the
1983 - DataFlash Support:
1984 CONFIG_HAS_DATAFLASH
1986 Defining this option enables DataFlash features and
1987 allows to read/write in Dataflash via the standard
1990 - SystemACE Support:
1993 Adding this option adds support for Xilinx SystemACE
1994 chips attached via some sort of local bus. The address
1995 of the chip must also be defined in the
1996 CONFIG_SYS_SYSTEMACE_BASE macro. For example:
1998 #define CONFIG_SYSTEMACE
1999 #define CONFIG_SYS_SYSTEMACE_BASE 0xf0000000
2001 When SystemACE support is added, the "ace" device type
2002 becomes available to the fat commands, i.e. fatls.
2004 - TFTP Fixed UDP Port:
2007 If this is defined, the environment variable tftpsrcp
2008 is used to supply the TFTP UDP source port value.
2009 If tftpsrcp isn't defined, the normal pseudo-random port
2010 number generator is used.
2012 Also, the environment variable tftpdstp is used to supply
2013 the TFTP UDP destination port value. If tftpdstp isn't
2014 defined, the normal port 69 is used.
2016 The purpose for tftpsrcp is to allow a TFTP server to
2017 blindly start the TFTP transfer using the pre-configured
2018 target IP address and UDP port. This has the effect of
2019 "punching through" the (Windows XP) firewall, allowing
2020 the remainder of the TFTP transfer to proceed normally.
2021 A better solution is to properly configure the firewall,
2022 but sometimes that is not allowed.
2024 - Show boot progress:
2025 CONFIG_SHOW_BOOT_PROGRESS
2027 Defining this option allows to add some board-
2028 specific code (calling a user-provided function
2029 "show_boot_progress(int)") that enables you to show
2030 the system's boot progress on some display (for
2031 example, some LED's) on your board. At the moment,
2032 the following checkpoints are implemented:
2034 - Standalone program support:
2035 CONFIG_STANDALONE_LOAD_ADDR
2037 This option allows to define board specific values
2038 for the address where standalone program gets loaded,
2039 thus overwriting the architecutre dependent default
2042 - Frame Buffer Address:
2045 Define CONFIG_FB_ADDR if you want to use specific address for
2047 Then system will reserve the frame buffer address to defined address
2048 instead of lcd_setmem (this function grab the memory for frame buffer
2051 Please see board_init_f function.
2053 If you want this config option then,
2054 please define it at your board config file
2056 Legacy uImage format:
2059 1 common/cmd_bootm.c before attempting to boot an image
2060 -1 common/cmd_bootm.c Image header has bad magic number
2061 2 common/cmd_bootm.c Image header has correct magic number
2062 -2 common/cmd_bootm.c Image header has bad checksum
2063 3 common/cmd_bootm.c Image header has correct checksum
2064 -3 common/cmd_bootm.c Image data has bad checksum
2065 4 common/cmd_bootm.c Image data has correct checksum
2066 -4 common/cmd_bootm.c Image is for unsupported architecture
2067 5 common/cmd_bootm.c Architecture check OK
2068 -5 common/cmd_bootm.c Wrong Image Type (not kernel, multi)
2069 6 common/cmd_bootm.c Image Type check OK
2070 -6 common/cmd_bootm.c gunzip uncompression error
2071 -7 common/cmd_bootm.c Unimplemented compression type
2072 7 common/cmd_bootm.c Uncompression OK
2073 8 common/cmd_bootm.c No uncompress/copy overwrite error
2074 -9 common/cmd_bootm.c Unsupported OS (not Linux, BSD, VxWorks, QNX)
2076 9 common/image.c Start initial ramdisk verification
2077 -10 common/image.c Ramdisk header has bad magic number
2078 -11 common/image.c Ramdisk header has bad checksum
2079 10 common/image.c Ramdisk header is OK
2080 -12 common/image.c Ramdisk data has bad checksum
2081 11 common/image.c Ramdisk data has correct checksum
2082 12 common/image.c Ramdisk verification complete, start loading
2083 -13 common/image.c Wrong Image Type (not PPC Linux ramdisk)
2084 13 common/image.c Start multifile image verification
2085 14 common/image.c No initial ramdisk, no multifile, continue.
2087 15 arch/<arch>/lib/bootm.c All preparation done, transferring control to OS
2089 -30 arch/powerpc/lib/board.c Fatal error, hang the system
2090 -31 post/post.c POST test failed, detected by post_output_backlog()
2091 -32 post/post.c POST test failed, detected by post_run_single()
2093 34 common/cmd_doc.c before loading a Image from a DOC device
2094 -35 common/cmd_doc.c Bad usage of "doc" command
2095 35 common/cmd_doc.c correct usage of "doc" command
2096 -36 common/cmd_doc.c No boot device
2097 36 common/cmd_doc.c correct boot device
2098 -37 common/cmd_doc.c Unknown Chip ID on boot device
2099 37 common/cmd_doc.c correct chip ID found, device available
2100 -38 common/cmd_doc.c Read Error on boot device
2101 38 common/cmd_doc.c reading Image header from DOC device OK
2102 -39 common/cmd_doc.c Image header has bad magic number
2103 39 common/cmd_doc.c Image header has correct magic number
2104 -40 common/cmd_doc.c Error reading Image from DOC device
2105 40 common/cmd_doc.c Image header has correct magic number
2106 41 common/cmd_ide.c before loading a Image from a IDE device
2107 -42 common/cmd_ide.c Bad usage of "ide" command
2108 42 common/cmd_ide.c correct usage of "ide" command
2109 -43 common/cmd_ide.c No boot device
2110 43 common/cmd_ide.c boot device found
2111 -44 common/cmd_ide.c Device not available
2112 44 common/cmd_ide.c Device available
2113 -45 common/cmd_ide.c wrong partition selected
2114 45 common/cmd_ide.c partition selected
2115 -46 common/cmd_ide.c Unknown partition table
2116 46 common/cmd_ide.c valid partition table found
2117 -47 common/cmd_ide.c Invalid partition type
2118 47 common/cmd_ide.c correct partition type
2119 -48 common/cmd_ide.c Error reading Image Header on boot device
2120 48 common/cmd_ide.c reading Image Header from IDE device OK
2121 -49 common/cmd_ide.c Image header has bad magic number
2122 49 common/cmd_ide.c Image header has correct magic number
2123 -50 common/cmd_ide.c Image header has bad checksum
2124 50 common/cmd_ide.c Image header has correct checksum
2125 -51 common/cmd_ide.c Error reading Image from IDE device
2126 51 common/cmd_ide.c reading Image from IDE device OK
2127 52 common/cmd_nand.c before loading a Image from a NAND device
2128 -53 common/cmd_nand.c Bad usage of "nand" command
2129 53 common/cmd_nand.c correct usage of "nand" command
2130 -54 common/cmd_nand.c No boot device
2131 54 common/cmd_nand.c boot device found
2132 -55 common/cmd_nand.c Unknown Chip ID on boot device
2133 55 common/cmd_nand.c correct chip ID found, device available
2134 -56 common/cmd_nand.c Error reading Image Header on boot device
2135 56 common/cmd_nand.c reading Image Header from NAND device OK
2136 -57 common/cmd_nand.c Image header has bad magic number
2137 57 common/cmd_nand.c Image header has correct magic number
2138 -58 common/cmd_nand.c Error reading Image from NAND device
2139 58 common/cmd_nand.c reading Image from NAND device OK
2141 -60 common/env_common.c Environment has a bad CRC, using default
2143 64 net/eth.c starting with Ethernet configuration.
2144 -64 net/eth.c no Ethernet found.
2145 65 net/eth.c Ethernet found.
2147 -80 common/cmd_net.c usage wrong
2148 80 common/cmd_net.c before calling NetLoop()
2149 -81 common/cmd_net.c some error in NetLoop() occurred
2150 81 common/cmd_net.c NetLoop() back without error
2151 -82 common/cmd_net.c size == 0 (File with size 0 loaded)
2152 82 common/cmd_net.c trying automatic boot
2153 83 common/cmd_net.c running "source" command
2154 -83 common/cmd_net.c some error in automatic boot or "source" command
2155 84 common/cmd_net.c end without errors
2160 100 common/cmd_bootm.c Kernel FIT Image has correct format
2161 -100 common/cmd_bootm.c Kernel FIT Image has incorrect format
2162 101 common/cmd_bootm.c No Kernel subimage unit name, using configuration
2163 -101 common/cmd_bootm.c Can't get configuration for kernel subimage
2164 102 common/cmd_bootm.c Kernel unit name specified
2165 -103 common/cmd_bootm.c Can't get kernel subimage node offset
2166 103 common/cmd_bootm.c Found configuration node
2167 104 common/cmd_bootm.c Got kernel subimage node offset
2168 -104 common/cmd_bootm.c Kernel subimage hash verification failed
2169 105 common/cmd_bootm.c Kernel subimage hash verification OK
2170 -105 common/cmd_bootm.c Kernel subimage is for unsupported architecture
2171 106 common/cmd_bootm.c Architecture check OK
2172 -106 common/cmd_bootm.c Kernel subimage has wrong type
2173 107 common/cmd_bootm.c Kernel subimage type OK
2174 -107 common/cmd_bootm.c Can't get kernel subimage data/size
2175 108 common/cmd_bootm.c Got kernel subimage data/size
2176 -108 common/cmd_bootm.c Wrong image type (not legacy, FIT)
2177 -109 common/cmd_bootm.c Can't get kernel subimage type
2178 -110 common/cmd_bootm.c Can't get kernel subimage comp
2179 -111 common/cmd_bootm.c Can't get kernel subimage os
2180 -112 common/cmd_bootm.c Can't get kernel subimage load address
2181 -113 common/cmd_bootm.c Image uncompress/copy overwrite error
2183 120 common/image.c Start initial ramdisk verification
2184 -120 common/image.c Ramdisk FIT image has incorrect format
2185 121 common/image.c Ramdisk FIT image has correct format
2186 122 common/image.c No ramdisk subimage unit name, using configuration
2187 -122 common/image.c Can't get configuration for ramdisk subimage
2188 123 common/image.c Ramdisk unit name specified
2189 -124 common/image.c Can't get ramdisk subimage node offset
2190 125 common/image.c Got ramdisk subimage node offset
2191 -125 common/image.c Ramdisk subimage hash verification failed
2192 126 common/image.c Ramdisk subimage hash verification OK
2193 -126 common/image.c Ramdisk subimage for unsupported architecture
2194 127 common/image.c Architecture check OK
2195 -127 common/image.c Can't get ramdisk subimage data/size
2196 128 common/image.c Got ramdisk subimage data/size
2197 129 common/image.c Can't get ramdisk load address
2198 -129 common/image.c Got ramdisk load address
2200 -130 common/cmd_doc.c Incorrect FIT image format
2201 131 common/cmd_doc.c FIT image format OK
2203 -140 common/cmd_ide.c Incorrect FIT image format
2204 141 common/cmd_ide.c FIT image format OK
2206 -150 common/cmd_nand.c Incorrect FIT image format
2207 151 common/cmd_nand.c FIT image format OK
2209 - Automatic software updates via TFTP server
2211 CONFIG_UPDATE_TFTP_CNT_MAX
2212 CONFIG_UPDATE_TFTP_MSEC_MAX
2214 These options enable and control the auto-update feature;
2215 for a more detailed description refer to doc/README.update.
2217 - MTD Support (mtdparts command, UBI support)
2220 Adds the MTD device infrastructure from the Linux kernel.
2221 Needed for mtdparts command support.
2223 CONFIG_MTD_PARTITIONS
2225 Adds the MTD partitioning infrastructure from the Linux
2226 kernel. Needed for UBI support.
2232 [so far only for SMDK2400 boards]
2234 - Modem support enable:
2235 CONFIG_MODEM_SUPPORT
2237 - RTS/CTS Flow control enable:
2240 - Modem debug support:
2241 CONFIG_MODEM_SUPPORT_DEBUG
2243 Enables debugging stuff (char screen[1024], dbg())
2244 for modem support. Useful only with BDI2000.
2246 - Interrupt support (PPC):
2248 There are common interrupt_init() and timer_interrupt()
2249 for all PPC archs. interrupt_init() calls interrupt_init_cpu()
2250 for CPU specific initialization. interrupt_init_cpu()
2251 should set decrementer_count to appropriate value. If
2252 CPU resets decrementer automatically after interrupt
2253 (ppc4xx) it should set decrementer_count to zero.
2254 timer_interrupt() calls timer_interrupt_cpu() for CPU
2255 specific handling. If board has watchdog / status_led
2256 / other_activity_monitor it works automatically from
2257 general timer_interrupt().
2261 In the target system modem support is enabled when a
2262 specific key (key combination) is pressed during
2263 power-on. Otherwise U-Boot will boot normally
2264 (autoboot). The key_pressed() function is called from
2265 board_init(). Currently key_pressed() is a dummy
2266 function, returning 1 and thus enabling modem
2269 If there are no modem init strings in the
2270 environment, U-Boot proceed to autoboot; the
2271 previous output (banner, info printfs) will be
2274 See also: doc/README.Modem
2277 Configuration Settings:
2278 -----------------------
2280 - CONFIG_SYS_LONGHELP: Defined when you want long help messages included;
2281 undefine this when you're short of memory.
2283 - CONFIG_SYS_HELP_CMD_WIDTH: Defined when you want to override the default
2284 width of the commands listed in the 'help' command output.
2286 - CONFIG_SYS_PROMPT: This is what U-Boot prints on the console to
2287 prompt for user input.
2289 - CONFIG_SYS_CBSIZE: Buffer size for input from the Console
2291 - CONFIG_SYS_PBSIZE: Buffer size for Console output
2293 - CONFIG_SYS_MAXARGS: max. Number of arguments accepted for monitor commands
2295 - CONFIG_SYS_BARGSIZE: Buffer size for Boot Arguments which are passed to
2296 the application (usually a Linux kernel) when it is
2299 - CONFIG_SYS_BAUDRATE_TABLE:
2300 List of legal baudrate settings for this board.
2302 - CONFIG_SYS_CONSOLE_INFO_QUIET
2303 Suppress display of console information at boot.
2305 - CONFIG_SYS_CONSOLE_IS_IN_ENV
2306 If the board specific function
2307 extern int overwrite_console (void);
2308 returns 1, the stdin, stderr and stdout are switched to the
2309 serial port, else the settings in the environment are used.
2311 - CONFIG_SYS_CONSOLE_OVERWRITE_ROUTINE
2312 Enable the call to overwrite_console().
2314 - CONFIG_SYS_CONSOLE_ENV_OVERWRITE
2315 Enable overwrite of previous console environment settings.
2317 - CONFIG_SYS_MEMTEST_START, CONFIG_SYS_MEMTEST_END:
2318 Begin and End addresses of the area used by the
2321 - CONFIG_SYS_ALT_MEMTEST:
2322 Enable an alternate, more extensive memory test.
2324 - CONFIG_SYS_MEMTEST_SCRATCH:
2325 Scratch address used by the alternate memory test
2326 You only need to set this if address zero isn't writeable
2328 - CONFIG_SYS_MEM_TOP_HIDE (PPC only):
2329 If CONFIG_SYS_MEM_TOP_HIDE is defined in the board config header,
2330 this specified memory area will get subtracted from the top
2331 (end) of RAM and won't get "touched" at all by U-Boot. By
2332 fixing up gd->ram_size the Linux kernel should gets passed
2333 the now "corrected" memory size and won't touch it either.
2334 This should work for arch/ppc and arch/powerpc. Only Linux
2335 board ports in arch/powerpc with bootwrapper support that
2336 recalculate the memory size from the SDRAM controller setup
2337 will have to get fixed in Linux additionally.
2339 This option can be used as a workaround for the 440EPx/GRx
2340 CHIP 11 errata where the last 256 bytes in SDRAM shouldn't
2343 WARNING: Please make sure that this value is a multiple of
2344 the Linux page size (normally 4k). If this is not the case,
2345 then the end address of the Linux memory will be located at a
2346 non page size aligned address and this could cause major
2349 - CONFIG_SYS_TFTP_LOADADDR:
2350 Default load address for network file downloads
2352 - CONFIG_SYS_LOADS_BAUD_CHANGE:
2353 Enable temporary baudrate change while serial download
2355 - CONFIG_SYS_SDRAM_BASE:
2356 Physical start address of SDRAM. _Must_ be 0 here.
2358 - CONFIG_SYS_MBIO_BASE:
2359 Physical start address of Motherboard I/O (if using a
2362 - CONFIG_SYS_FLASH_BASE:
2363 Physical start address of Flash memory.
2365 - CONFIG_SYS_MONITOR_BASE:
2366 Physical start address of boot monitor code (set by
2367 make config files to be same as the text base address
2368 (CONFIG_SYS_TEXT_BASE) used when linking) - same as
2369 CONFIG_SYS_FLASH_BASE when booting from flash.
2371 - CONFIG_SYS_MONITOR_LEN:
2372 Size of memory reserved for monitor code, used to
2373 determine _at_compile_time_ (!) if the environment is
2374 embedded within the U-Boot image, or in a separate
2377 - CONFIG_SYS_MALLOC_LEN:
2378 Size of DRAM reserved for malloc() use.
2380 - CONFIG_SYS_BOOTM_LEN:
2381 Normally compressed uImages are limited to an
2382 uncompressed size of 8 MBytes. If this is not enough,
2383 you can define CONFIG_SYS_BOOTM_LEN in your board config file
2384 to adjust this setting to your needs.
2386 - CONFIG_SYS_BOOTMAPSZ:
2387 Maximum size of memory mapped by the startup code of
2388 the Linux kernel; all data that must be processed by
2389 the Linux kernel (bd_info, boot arguments, FDT blob if
2390 used) must be put below this limit, unless "bootm_low"
2391 enviroment variable is defined and non-zero. In such case
2392 all data for the Linux kernel must be between "bootm_low"
2393 and "bootm_low" + CONFIG_SYS_BOOTMAPSZ. The environment
2394 variable "bootm_mapsize" will override the value of
2395 CONFIG_SYS_BOOTMAPSZ. If CONFIG_SYS_BOOTMAPSZ is undefined,
2396 then the value in "bootm_size" will be used instead.
2398 - CONFIG_SYS_BOOT_RAMDISK_HIGH:
2399 Enable initrd_high functionality. If defined then the
2400 initrd_high feature is enabled and the bootm ramdisk subcommand
2403 - CONFIG_SYS_BOOT_GET_CMDLINE:
2404 Enables allocating and saving kernel cmdline in space between
2405 "bootm_low" and "bootm_low" + BOOTMAPSZ.
2407 - CONFIG_SYS_BOOT_GET_KBD:
2408 Enables allocating and saving a kernel copy of the bd_info in
2409 space between "bootm_low" and "bootm_low" + BOOTMAPSZ.
2411 - CONFIG_SYS_MAX_FLASH_BANKS:
2412 Max number of Flash memory banks
2414 - CONFIG_SYS_MAX_FLASH_SECT:
2415 Max number of sectors on a Flash chip
2417 - CONFIG_SYS_FLASH_ERASE_TOUT:
2418 Timeout for Flash erase operations (in ms)
2420 - CONFIG_SYS_FLASH_WRITE_TOUT:
2421 Timeout for Flash write operations (in ms)
2423 - CONFIG_SYS_FLASH_LOCK_TOUT
2424 Timeout for Flash set sector lock bit operation (in ms)
2426 - CONFIG_SYS_FLASH_UNLOCK_TOUT
2427 Timeout for Flash clear lock bits operation (in ms)
2429 - CONFIG_SYS_FLASH_PROTECTION
2430 If defined, hardware flash sectors protection is used
2431 instead of U-Boot software protection.
2433 - CONFIG_SYS_DIRECT_FLASH_TFTP:
2435 Enable TFTP transfers directly to flash memory;
2436 without this option such a download has to be
2437 performed in two steps: (1) download to RAM, and (2)
2438 copy from RAM to flash.
2440 The two-step approach is usually more reliable, since
2441 you can check if the download worked before you erase
2442 the flash, but in some situations (when system RAM is
2443 too limited to allow for a temporary copy of the
2444 downloaded image) this option may be very useful.
2446 - CONFIG_SYS_FLASH_CFI:
2447 Define if the flash driver uses extra elements in the
2448 common flash structure for storing flash geometry.
2450 - CONFIG_FLASH_CFI_DRIVER
2451 This option also enables the building of the cfi_flash driver
2452 in the drivers directory
2454 - CONFIG_FLASH_CFI_MTD
2455 This option enables the building of the cfi_mtd driver
2456 in the drivers directory. The driver exports CFI flash
2459 - CONFIG_SYS_FLASH_USE_BUFFER_WRITE
2460 Use buffered writes to flash.
2462 - CONFIG_FLASH_SPANSION_S29WS_N
2463 s29ws-n MirrorBit flash has non-standard addresses for buffered
2466 - CONFIG_SYS_FLASH_QUIET_TEST
2467 If this option is defined, the common CFI flash doesn't
2468 print it's warning upon not recognized FLASH banks. This
2469 is useful, if some of the configured banks are only
2470 optionally available.
2472 - CONFIG_FLASH_SHOW_PROGRESS
2473 If defined (must be an integer), print out countdown
2474 digits and dots. Recommended value: 45 (9..1) for 80
2475 column displays, 15 (3..1) for 40 column displays.
2477 - CONFIG_SYS_RX_ETH_BUFFER:
2478 Defines the number of Ethernet receive buffers. On some
2479 Ethernet controllers it is recommended to set this value
2480 to 8 or even higher (EEPRO100 or 405 EMAC), since all
2481 buffers can be full shortly after enabling the interface
2482 on high Ethernet traffic.
2483 Defaults to 4 if not defined.
2485 - CONFIG_ENV_MAX_ENTRIES
2487 Maximum number of entries in the hash table that is used
2488 internally to store the environment settings. The default
2489 setting is supposed to be generous and should work in most
2490 cases. This setting can be used to tune behaviour; see
2491 lib/hashtable.c for details.
2493 The following definitions that deal with the placement and management
2494 of environment data (variable area); in general, we support the
2495 following configurations:
2497 - CONFIG_ENV_IS_IN_FLASH:
2499 Define this if the environment is in flash memory.
2501 a) The environment occupies one whole flash sector, which is
2502 "embedded" in the text segment with the U-Boot code. This
2503 happens usually with "bottom boot sector" or "top boot
2504 sector" type flash chips, which have several smaller
2505 sectors at the start or the end. For instance, such a
2506 layout can have sector sizes of 8, 2x4, 16, Nx32 kB. In
2507 such a case you would place the environment in one of the
2508 4 kB sectors - with U-Boot code before and after it. With
2509 "top boot sector" type flash chips, you would put the
2510 environment in one of the last sectors, leaving a gap
2511 between U-Boot and the environment.
2513 - CONFIG_ENV_OFFSET:
2515 Offset of environment data (variable area) to the
2516 beginning of flash memory; for instance, with bottom boot
2517 type flash chips the second sector can be used: the offset
2518 for this sector is given here.
2520 CONFIG_ENV_OFFSET is used relative to CONFIG_SYS_FLASH_BASE.
2524 This is just another way to specify the start address of
2525 the flash sector containing the environment (instead of
2528 - CONFIG_ENV_SECT_SIZE:
2530 Size of the sector containing the environment.
2533 b) Sometimes flash chips have few, equal sized, BIG sectors.
2534 In such a case you don't want to spend a whole sector for
2539 If you use this in combination with CONFIG_ENV_IS_IN_FLASH
2540 and CONFIG_ENV_SECT_SIZE, you can specify to use only a part
2541 of this flash sector for the environment. This saves
2542 memory for the RAM copy of the environment.
2544 It may also save flash memory if you decide to use this
2545 when your environment is "embedded" within U-Boot code,
2546 since then the remainder of the flash sector could be used
2547 for U-Boot code. It should be pointed out that this is
2548 STRONGLY DISCOURAGED from a robustness point of view:
2549 updating the environment in flash makes it always
2550 necessary to erase the WHOLE sector. If something goes
2551 wrong before the contents has been restored from a copy in
2552 RAM, your target system will be dead.
2554 - CONFIG_ENV_ADDR_REDUND
2555 CONFIG_ENV_SIZE_REDUND
2557 These settings describe a second storage area used to hold
2558 a redundant copy of the environment data, so that there is
2559 a valid backup copy in case there is a power failure during
2560 a "saveenv" operation.
2562 BE CAREFUL! Any changes to the flash layout, and some changes to the
2563 source code will make it necessary to adapt <board>/u-boot.lds*
2567 - CONFIG_ENV_IS_IN_NVRAM:
2569 Define this if you have some non-volatile memory device
2570 (NVRAM, battery buffered SRAM) which you want to use for the
2576 These two #defines are used to determine the memory area you
2577 want to use for environment. It is assumed that this memory
2578 can just be read and written to, without any special
2581 BE CAREFUL! The first access to the environment happens quite early
2582 in U-Boot initalization (when we try to get the setting of for the
2583 console baudrate). You *MUST* have mapped your NVRAM area then, or
2586 Please note that even with NVRAM we still use a copy of the
2587 environment in RAM: we could work on NVRAM directly, but we want to
2588 keep settings there always unmodified except somebody uses "saveenv"
2589 to save the current settings.
2592 - CONFIG_ENV_IS_IN_EEPROM:
2594 Use this if you have an EEPROM or similar serial access
2595 device and a driver for it.
2597 - CONFIG_ENV_OFFSET:
2600 These two #defines specify the offset and size of the
2601 environment area within the total memory of your EEPROM.
2603 - CONFIG_SYS_I2C_EEPROM_ADDR:
2604 If defined, specified the chip address of the EEPROM device.
2605 The default address is zero.
2607 - CONFIG_SYS_EEPROM_PAGE_WRITE_BITS:
2608 If defined, the number of bits used to address bytes in a
2609 single page in the EEPROM device. A 64 byte page, for example
2610 would require six bits.
2612 - CONFIG_SYS_EEPROM_PAGE_WRITE_DELAY_MS:
2613 If defined, the number of milliseconds to delay between
2614 page writes. The default is zero milliseconds.
2616 - CONFIG_SYS_I2C_EEPROM_ADDR_LEN:
2617 The length in bytes of the EEPROM memory array address. Note
2618 that this is NOT the chip address length!
2620 - CONFIG_SYS_I2C_EEPROM_ADDR_OVERFLOW:
2621 EEPROM chips that implement "address overflow" are ones
2622 like Catalyst 24WC04/08/16 which has 9/10/11 bits of
2623 address and the extra bits end up in the "chip address" bit
2624 slots. This makes a 24WC08 (1Kbyte) chip look like four 256
2627 Note that we consider the length of the address field to
2628 still be one byte because the extra address bits are hidden
2629 in the chip address.
2631 - CONFIG_SYS_EEPROM_SIZE:
2632 The size in bytes of the EEPROM device.
2634 - CONFIG_ENV_EEPROM_IS_ON_I2C
2635 define this, if you have I2C and SPI activated, and your
2636 EEPROM, which holds the environment, is on the I2C bus.
2638 - CONFIG_I2C_ENV_EEPROM_BUS
2639 if you have an Environment on an EEPROM reached over
2640 I2C muxes, you can define here, how to reach this
2641 EEPROM. For example:
2643 #define CONFIG_I2C_ENV_EEPROM_BUS "pca9547:70:d\0"
2645 EEPROM which holds the environment, is reached over
2646 a pca9547 i2c mux with address 0x70, channel 3.
2648 - CONFIG_ENV_IS_IN_DATAFLASH:
2650 Define this if you have a DataFlash memory device which you
2651 want to use for the environment.
2653 - CONFIG_ENV_OFFSET:
2657 These three #defines specify the offset and size of the
2658 environment area within the total memory of your DataFlash placed
2659 at the specified address.
2661 - CONFIG_ENV_IS_IN_NAND:
2663 Define this if you have a NAND device which you want to use
2664 for the environment.
2666 - CONFIG_ENV_OFFSET:
2669 These two #defines specify the offset and size of the environment
2670 area within the first NAND device. CONFIG_ENV_OFFSET must be
2671 aligned to an erase block boundary.
2673 - CONFIG_ENV_OFFSET_REDUND (optional):
2675 This setting describes a second storage area of CONFIG_ENV_SIZE
2676 size used to hold a redundant copy of the environment data, so
2677 that there is a valid backup copy in case there is a power failure
2678 during a "saveenv" operation. CONFIG_ENV_OFFSET_RENDUND must be
2679 aligned to an erase block boundary.
2681 - CONFIG_ENV_RANGE (optional):
2683 Specifies the length of the region in which the environment
2684 can be written. This should be a multiple of the NAND device's
2685 block size. Specifying a range with more erase blocks than
2686 are needed to hold CONFIG_ENV_SIZE allows bad blocks within
2687 the range to be avoided.
2689 - CONFIG_ENV_OFFSET_OOB (optional):
2691 Enables support for dynamically retrieving the offset of the
2692 environment from block zero's out-of-band data. The
2693 "nand env.oob" command can be used to record this offset.
2694 Currently, CONFIG_ENV_OFFSET_REDUND is not supported when
2695 using CONFIG_ENV_OFFSET_OOB.
2697 - CONFIG_NAND_ENV_DST
2699 Defines address in RAM to which the nand_spl code should copy the
2700 environment. If redundant environment is used, it will be copied to
2701 CONFIG_NAND_ENV_DST + CONFIG_ENV_SIZE.
2703 - CONFIG_SYS_SPI_INIT_OFFSET
2705 Defines offset to the initial SPI buffer area in DPRAM. The
2706 area is used at an early stage (ROM part) if the environment
2707 is configured to reside in the SPI EEPROM: We need a 520 byte
2708 scratch DPRAM area. It is used between the two initialization
2709 calls (spi_init_f() and spi_init_r()). A value of 0xB00 seems
2710 to be a good choice since it makes it far enough from the
2711 start of the data area as well as from the stack pointer.
2713 Please note that the environment is read-only until the monitor
2714 has been relocated to RAM and a RAM copy of the environment has been
2715 created; also, when using EEPROM you will have to use getenv_f()
2716 until then to read environment variables.
2718 The environment is protected by a CRC32 checksum. Before the monitor
2719 is relocated into RAM, as a result of a bad CRC you will be working
2720 with the compiled-in default environment - *silently*!!! [This is
2721 necessary, because the first environment variable we need is the
2722 "baudrate" setting for the console - if we have a bad CRC, we don't
2723 have any device yet where we could complain.]
2725 Note: once the monitor has been relocated, then it will complain if
2726 the default environment is used; a new CRC is computed as soon as you
2727 use the "saveenv" command to store a valid environment.
2729 - CONFIG_SYS_FAULT_ECHO_LINK_DOWN:
2730 Echo the inverted Ethernet link state to the fault LED.
2732 Note: If this option is active, then CONFIG_SYS_FAULT_MII_ADDR
2733 also needs to be defined.
2735 - CONFIG_SYS_FAULT_MII_ADDR:
2736 MII address of the PHY to check for the Ethernet link state.
2738 - CONFIG_NS16550_MIN_FUNCTIONS:
2739 Define this if you desire to only have use of the NS16550_init
2740 and NS16550_putc functions for the serial driver located at
2741 drivers/serial/ns16550.c. This option is useful for saving
2742 space for already greatly restricted images, including but not
2743 limited to NAND_SPL configurations.
2745 Low Level (hardware related) configuration options:
2746 ---------------------------------------------------
2748 - CONFIG_SYS_CACHELINE_SIZE:
2749 Cache Line Size of the CPU.
2751 - CONFIG_SYS_DEFAULT_IMMR:
2752 Default address of the IMMR after system reset.
2754 Needed on some 8260 systems (MPC8260ADS, PQ2FADS-ZU,
2755 and RPXsuper) to be able to adjust the position of
2756 the IMMR register after a reset.
2758 - Floppy Disk Support:
2759 CONFIG_SYS_FDC_DRIVE_NUMBER
2761 the default drive number (default value 0)
2763 CONFIG_SYS_ISA_IO_STRIDE
2765 defines the spacing between FDC chipset registers
2768 CONFIG_SYS_ISA_IO_OFFSET
2770 defines the offset of register from address. It
2771 depends on which part of the data bus is connected to
2772 the FDC chipset. (default value 0)
2774 If CONFIG_SYS_ISA_IO_STRIDE CONFIG_SYS_ISA_IO_OFFSET and
2775 CONFIG_SYS_FDC_DRIVE_NUMBER are undefined, they take their
2778 if CONFIG_SYS_FDC_HW_INIT is defined, then the function
2779 fdc_hw_init() is called at the beginning of the FDC
2780 setup. fdc_hw_init() must be provided by the board
2781 source code. It is used to make hardware dependant
2785 Most IDE controllers were designed to be connected with PCI
2786 interface. Only few of them were designed for AHB interface.
2787 When software is doing ATA command and data transfer to
2788 IDE devices through IDE-AHB controller, some additional
2789 registers accessing to these kind of IDE-AHB controller
2792 - CONFIG_SYS_IMMR: Physical address of the Internal Memory.
2793 DO NOT CHANGE unless you know exactly what you're
2794 doing! (11-4) [MPC8xx/82xx systems only]
2796 - CONFIG_SYS_INIT_RAM_ADDR:
2798 Start address of memory area that can be used for
2799 initial data and stack; please note that this must be
2800 writable memory that is working WITHOUT special
2801 initialization, i. e. you CANNOT use normal RAM which
2802 will become available only after programming the
2803 memory controller and running certain initialization
2806 U-Boot uses the following memory types:
2807 - MPC8xx and MPC8260: IMMR (internal memory of the CPU)
2808 - MPC824X: data cache
2809 - PPC4xx: data cache
2811 - CONFIG_SYS_GBL_DATA_OFFSET:
2813 Offset of the initial data structure in the memory
2814 area defined by CONFIG_SYS_INIT_RAM_ADDR. Usually
2815 CONFIG_SYS_GBL_DATA_OFFSET is chosen such that the initial
2816 data is located at the end of the available space
2817 (sometimes written as (CONFIG_SYS_INIT_RAM_SIZE -
2818 CONFIG_SYS_INIT_DATA_SIZE), and the initial stack is just
2819 below that area (growing from (CONFIG_SYS_INIT_RAM_ADDR +
2820 CONFIG_SYS_GBL_DATA_OFFSET) downward.
2823 On the MPC824X (or other systems that use the data
2824 cache for initial memory) the address chosen for
2825 CONFIG_SYS_INIT_RAM_ADDR is basically arbitrary - it must
2826 point to an otherwise UNUSED address space between
2827 the top of RAM and the start of the PCI space.
2829 - CONFIG_SYS_SIUMCR: SIU Module Configuration (11-6)
2831 - CONFIG_SYS_SYPCR: System Protection Control (11-9)
2833 - CONFIG_SYS_TBSCR: Time Base Status and Control (11-26)
2835 - CONFIG_SYS_PISCR: Periodic Interrupt Status and Control (11-31)
2837 - CONFIG_SYS_PLPRCR: PLL, Low-Power, and Reset Control Register (15-30)
2839 - CONFIG_SYS_SCCR: System Clock and reset Control Register (15-27)
2841 - CONFIG_SYS_OR_TIMING_SDRAM:
2844 - CONFIG_SYS_MAMR_PTA:
2845 periodic timer for refresh
2847 - CONFIG_SYS_DER: Debug Event Register (37-47)
2849 - FLASH_BASE0_PRELIM, FLASH_BASE1_PRELIM, CONFIG_SYS_REMAP_OR_AM,
2850 CONFIG_SYS_PRELIM_OR_AM, CONFIG_SYS_OR_TIMING_FLASH, CONFIG_SYS_OR0_REMAP,
2851 CONFIG_SYS_OR0_PRELIM, CONFIG_SYS_BR0_PRELIM, CONFIG_SYS_OR1_REMAP, CONFIG_SYS_OR1_PRELIM,
2852 CONFIG_SYS_BR1_PRELIM:
2853 Memory Controller Definitions: BR0/1 and OR0/1 (FLASH)
2855 - SDRAM_BASE2_PRELIM, SDRAM_BASE3_PRELIM, SDRAM_MAX_SIZE,
2856 CONFIG_SYS_OR_TIMING_SDRAM, CONFIG_SYS_OR2_PRELIM, CONFIG_SYS_BR2_PRELIM,
2857 CONFIG_SYS_OR3_PRELIM, CONFIG_SYS_BR3_PRELIM:
2858 Memory Controller Definitions: BR2/3 and OR2/3 (SDRAM)
2860 - CONFIG_SYS_MAMR_PTA, CONFIG_SYS_MPTPR_2BK_4K, CONFIG_SYS_MPTPR_1BK_4K, CONFIG_SYS_MPTPR_2BK_8K,
2861 CONFIG_SYS_MPTPR_1BK_8K, CONFIG_SYS_MAMR_8COL, CONFIG_SYS_MAMR_9COL:
2862 Machine Mode Register and Memory Periodic Timer
2863 Prescaler definitions (SDRAM timing)
2865 - CONFIG_SYS_I2C_UCODE_PATCH, CONFIG_SYS_I2C_DPMEM_OFFSET [0x1FC0]:
2866 enable I2C microcode relocation patch (MPC8xx);
2867 define relocation offset in DPRAM [DSP2]
2869 - CONFIG_SYS_SMC_UCODE_PATCH, CONFIG_SYS_SMC_DPMEM_OFFSET [0x1FC0]:
2870 enable SMC microcode relocation patch (MPC8xx);
2871 define relocation offset in DPRAM [SMC1]
2873 - CONFIG_SYS_SPI_UCODE_PATCH, CONFIG_SYS_SPI_DPMEM_OFFSET [0x1FC0]:
2874 enable SPI microcode relocation patch (MPC8xx);
2875 define relocation offset in DPRAM [SCC4]
2877 - CONFIG_SYS_USE_OSCCLK:
2878 Use OSCM clock mode on MBX8xx board. Be careful,
2879 wrong setting might damage your board. Read
2880 doc/README.MBX before setting this variable!
2882 - CONFIG_SYS_CPM_POST_WORD_ADDR: (MPC8xx, MPC8260 only)
2883 Offset of the bootmode word in DPRAM used by post
2884 (Power On Self Tests). This definition overrides
2885 #define'd default value in commproc.h resp.
2888 - CONFIG_SYS_PCI_SLV_MEM_LOCAL, CONFIG_SYS_PCI_SLV_MEM_BUS, CONFIG_SYS_PICMR0_MASK_ATTRIB,
2889 CONFIG_SYS_PCI_MSTR0_LOCAL, CONFIG_SYS_PCIMSK0_MASK, CONFIG_SYS_PCI_MSTR1_LOCAL,
2890 CONFIG_SYS_PCIMSK1_MASK, CONFIG_SYS_PCI_MSTR_MEM_LOCAL, CONFIG_SYS_PCI_MSTR_MEM_BUS,
2891 CONFIG_SYS_CPU_PCI_MEM_START, CONFIG_SYS_PCI_MSTR_MEM_SIZE, CONFIG_SYS_POCMR0_MASK_ATTRIB,
2892 CONFIG_SYS_PCI_MSTR_MEMIO_LOCAL, CONFIG_SYS_PCI_MSTR_MEMIO_BUS, CPU_PCI_MEMIO_START,
2893 CONFIG_SYS_PCI_MSTR_MEMIO_SIZE, CONFIG_SYS_POCMR1_MASK_ATTRIB, CONFIG_SYS_PCI_MSTR_IO_LOCAL,
2894 CONFIG_SYS_PCI_MSTR_IO_BUS, CONFIG_SYS_CPU_PCI_IO_START, CONFIG_SYS_PCI_MSTR_IO_SIZE,
2895 CONFIG_SYS_POCMR2_MASK_ATTRIB: (MPC826x only)
2896 Overrides the default PCI memory map in arch/powerpc/cpu/mpc8260/pci.c if set.
2898 - CONFIG_PCI_DISABLE_PCIE:
2899 Disable PCI-Express on systems where it is supported but not
2903 Chip has SRIO or not
2906 Board has SRIO 1 port available
2909 Board has SRIO 2 port available
2911 - CONFIG_SYS_SRIOn_MEM_VIRT:
2912 Virtual Address of SRIO port 'n' memory region
2914 - CONFIG_SYS_SRIOn_MEM_PHYS:
2915 Physical Address of SRIO port 'n' memory region
2917 - CONFIG_SYS_SRIOn_MEM_SIZE:
2918 Size of SRIO port 'n' memory region
2920 - CONFIG_SYS_NDFC_16
2921 Defined to tell the NDFC that the NAND chip is using a
2924 - CONFIG_SYS_NDFC_EBC0_CFG
2925 Sets the EBC0_CFG register for the NDFC. If not defined
2926 a default value will be used.
2929 Get DDR timing information from an I2C EEPROM. Common
2930 with pluggable memory modules such as SODIMMs
2933 I2C address of the SPD EEPROM
2935 - CONFIG_SYS_SPD_BUS_NUM
2936 If SPD EEPROM is on an I2C bus other than the first
2937 one, specify here. Note that the value must resolve
2938 to something your driver can deal with.
2940 - CONFIG_SYS_83XX_DDR_USES_CS0
2941 Only for 83xx systems. If specified, then DDR should
2942 be configured using CS0 and CS1 instead of CS2 and CS3.
2944 - CONFIG_ETHER_ON_FEC[12]
2945 Define to enable FEC[12] on a 8xx series processor.
2947 - CONFIG_FEC[12]_PHY
2948 Define to the hardcoded PHY address which corresponds
2949 to the given FEC; i. e.
2950 #define CONFIG_FEC1_PHY 4
2951 means that the PHY with address 4 is connected to FEC1
2953 When set to -1, means to probe for first available.
2955 - CONFIG_FEC[12]_PHY_NORXERR
2956 The PHY does not have a RXERR line (RMII only).
2957 (so program the FEC to ignore it).
2960 Enable RMII mode for all FECs.
2961 Note that this is a global option, we can't
2962 have one FEC in standard MII mode and another in RMII mode.
2964 - CONFIG_CRC32_VERIFY
2965 Add a verify option to the crc32 command.
2968 => crc32 -v <address> <count> <crc32>
2970 Where address/count indicate a memory area
2971 and crc32 is the correct crc32 which the
2975 Add the "loopw" memory command. This only takes effect if
2976 the memory commands are activated globally (CONFIG_CMD_MEM).
2979 Add the "mdc" and "mwc" memory commands. These are cyclic
2984 This command will print 4 bytes (10,11,12,13) each 500 ms.
2986 => mwc.l 100 12345678 10
2987 This command will write 12345678 to address 100 all 10 ms.
2989 This only takes effect if the memory commands are activated
2990 globally (CONFIG_CMD_MEM).
2992 - CONFIG_SKIP_LOWLEVEL_INIT
2993 [ARM only] If this variable is defined, then certain
2994 low level initializations (like setting up the memory
2995 controller) are omitted and/or U-Boot does not
2996 relocate itself into RAM.
2998 Normally this variable MUST NOT be defined. The only
2999 exception is when U-Boot is loaded (to RAM) by some
3000 other boot loader or by a debugger which performs
3001 these initializations itself.
3004 Modifies the behaviour of start.S when compiling a loader
3005 that is executed before the actual U-Boot. E.g. when
3006 compiling a NAND SPL.
3008 - CONFIG_USE_ARCH_MEMCPY
3009 CONFIG_USE_ARCH_MEMSET
3010 If these options are used a optimized version of memcpy/memset will
3011 be used if available. These functions may be faster under some
3012 conditions but may increase the binary size.
3014 Building the Software:
3015 ======================
3017 Building U-Boot has been tested in several native build environments
3018 and in many different cross environments. Of course we cannot support
3019 all possibly existing versions of cross development tools in all
3020 (potentially obsolete) versions. In case of tool chain problems we
3021 recommend to use the ELDK (see http://www.denx.de/wiki/DULG/ELDK)
3022 which is extensively used to build and test U-Boot.
3024 If you are not using a native environment, it is assumed that you
3025 have GNU cross compiling tools available in your path. In this case,
3026 you must set the environment variable CROSS_COMPILE in your shell.
3027 Note that no changes to the Makefile or any other source files are
3028 necessary. For example using the ELDK on a 4xx CPU, please enter:
3030 $ CROSS_COMPILE=ppc_4xx-
3031 $ export CROSS_COMPILE
3033 Note: If you wish to generate Windows versions of the utilities in
3034 the tools directory you can use the MinGW toolchain
3035 (http://www.mingw.org). Set your HOST tools to the MinGW
3036 toolchain and execute 'make tools'. For example:
3038 $ make HOSTCC=i586-mingw32msvc-gcc HOSTSTRIP=i586-mingw32msvc-strip tools
3040 Binaries such as tools/mkimage.exe will be created which can
3041 be executed on computers running Windows.
3043 U-Boot is intended to be simple to build. After installing the
3044 sources you must configure U-Boot for one specific board type. This
3049 where "NAME_config" is the name of one of the existing configu-
3050 rations; see the main Makefile for supported names.
3052 Note: for some board special configuration names may exist; check if
3053 additional information is available from the board vendor; for
3054 instance, the TQM823L systems are available without (standard)
3055 or with LCD support. You can select such additional "features"
3056 when choosing the configuration, i. e.
3059 - will configure for a plain TQM823L, i. e. no LCD support
3061 make TQM823L_LCD_config
3062 - will configure for a TQM823L with U-Boot console on LCD
3067 Finally, type "make all", and you should get some working U-Boot
3068 images ready for download to / installation on your system:
3070 - "u-boot.bin" is a raw binary image
3071 - "u-boot" is an image in ELF binary format
3072 - "u-boot.srec" is in Motorola S-Record format
3074 By default the build is performed locally and the objects are saved
3075 in the source directory. One of the two methods can be used to change
3076 this behavior and build U-Boot to some external directory:
3078 1. Add O= to the make command line invocations:
3080 make O=/tmp/build distclean
3081 make O=/tmp/build NAME_config
3082 make O=/tmp/build all
3084 2. Set environment variable BUILD_DIR to point to the desired location:
3086 export BUILD_DIR=/tmp/build
3091 Note that the command line "O=" setting overrides the BUILD_DIR environment
3095 Please be aware that the Makefiles assume you are using GNU make, so
3096 for instance on NetBSD you might need to use "gmake" instead of
3100 If the system board that you have is not listed, then you will need
3101 to port U-Boot to your hardware platform. To do this, follow these
3104 1. Add a new configuration option for your board to the toplevel
3105 "Makefile" and to the "MAKEALL" script, using the existing
3106 entries as examples. Note that here and at many other places
3107 boards and other names are listed in alphabetical sort order. Please
3109 2. Create a new directory to hold your board specific code. Add any
3110 files you need. In your board directory, you will need at least
3111 the "Makefile", a "<board>.c", "flash.c" and "u-boot.lds".
3112 3. Create a new configuration file "include/configs/<board>.h" for
3114 3. If you're porting U-Boot to a new CPU, then also create a new
3115 directory to hold your CPU specific code. Add any files you need.
3116 4. Run "make <board>_config" with your new name.
3117 5. Type "make", and you should get a working "u-boot.srec" file
3118 to be installed on your target system.
3119 6. Debug and solve any problems that might arise.
3120 [Of course, this last step is much harder than it sounds.]
3123 Testing of U-Boot Modifications, Ports to New Hardware, etc.:
3124 ==============================================================
3126 If you have modified U-Boot sources (for instance added a new board
3127 or support for new devices, a new CPU, etc.) you are expected to
3128 provide feedback to the other developers. The feedback normally takes
3129 the form of a "patch", i. e. a context diff against a certain (latest
3130 official or latest in the git repository) version of U-Boot sources.
3132 But before you submit such a patch, please verify that your modifi-
3133 cation did not break existing code. At least make sure that *ALL* of
3134 the supported boards compile WITHOUT ANY compiler warnings. To do so,
3135 just run the "MAKEALL" script, which will configure and build U-Boot
3136 for ALL supported system. Be warned, this will take a while. You can
3137 select which (cross) compiler to use by passing a `CROSS_COMPILE'
3138 environment variable to the script, i. e. to use the ELDK cross tools
3141 CROSS_COMPILE=ppc_8xx- MAKEALL
3143 or to build on a native PowerPC system you can type
3145 CROSS_COMPILE=' ' MAKEALL
3147 When using the MAKEALL script, the default behaviour is to build
3148 U-Boot in the source directory. This location can be changed by
3149 setting the BUILD_DIR environment variable. Also, for each target
3150 built, the MAKEALL script saves two log files (<target>.ERR and
3151 <target>.MAKEALL) in the <source dir>/LOG directory. This default
3152 location can be changed by setting the MAKEALL_LOGDIR environment
3153 variable. For example:
3155 export BUILD_DIR=/tmp/build
3156 export MAKEALL_LOGDIR=/tmp/log
3157 CROSS_COMPILE=ppc_8xx- MAKEALL
3159 With the above settings build objects are saved in the /tmp/build,
3160 log files are saved in the /tmp/log and the source tree remains clean
3161 during the whole build process.
3164 See also "U-Boot Porting Guide" below.
3167 Monitor Commands - Overview:
3168 ============================
3170 go - start application at address 'addr'
3171 run - run commands in an environment variable
3172 bootm - boot application image from memory
3173 bootp - boot image via network using BootP/TFTP protocol
3174 tftpboot- boot image via network using TFTP protocol
3175 and env variables "ipaddr" and "serverip"
3176 (and eventually "gatewayip")
3177 rarpboot- boot image via network using RARP/TFTP protocol
3178 diskboot- boot from IDE devicebootd - boot default, i.e., run 'bootcmd'
3179 loads - load S-Record file over serial line
3180 loadb - load binary file over serial line (kermit mode)
3182 mm - memory modify (auto-incrementing)
3183 nm - memory modify (constant address)
3184 mw - memory write (fill)
3186 cmp - memory compare
3187 crc32 - checksum calculation
3188 i2c - I2C sub-system
3189 sspi - SPI utility commands
3190 base - print or set address offset
3191 printenv- print environment variables
3192 setenv - set environment variables
3193 saveenv - save environment variables to persistent storage
3194 protect - enable or disable FLASH write protection
3195 erase - erase FLASH memory
3196 flinfo - print FLASH memory information
3197 bdinfo - print Board Info structure
3198 iminfo - print header information for application image
3199 coninfo - print console devices and informations
3200 ide - IDE sub-system
3201 loop - infinite loop on address range
3202 loopw - infinite write loop on address range
3203 mtest - simple RAM test
3204 icache - enable or disable instruction cache
3205 dcache - enable or disable data cache
3206 reset - Perform RESET of the CPU
3207 echo - echo args to console
3208 version - print monitor version
3209 help - print online help
3210 ? - alias for 'help'
3213 Monitor Commands - Detailed Description:
3214 ========================================
3218 For now: just type "help <command>".
3221 Environment Variables:
3222 ======================
3224 U-Boot supports user configuration using Environment Variables which
3225 can be made persistent by saving to Flash memory.
3227 Environment Variables are set using "setenv", printed using
3228 "printenv", and saved to Flash using "saveenv". Using "setenv"
3229 without a value can be used to delete a variable from the
3230 environment. As long as you don't save the environment you are
3231 working with an in-memory copy. In case the Flash area containing the
3232 environment is erased by accident, a default environment is provided.
3234 Some configuration options can be set using Environment Variables.
3236 List of environment variables (most likely not complete):
3238 baudrate - see CONFIG_BAUDRATE
3240 bootdelay - see CONFIG_BOOTDELAY
3242 bootcmd - see CONFIG_BOOTCOMMAND
3244 bootargs - Boot arguments when booting an RTOS image
3246 bootfile - Name of the image to load with TFTP
3248 bootm_low - Memory range available for image processing in the bootm
3249 command can be restricted. This variable is given as
3250 a hexadecimal number and defines lowest address allowed
3251 for use by the bootm command. See also "bootm_size"
3252 environment variable. Address defined by "bootm_low" is
3253 also the base of the initial memory mapping for the Linux
3254 kernel -- see the description of CONFIG_SYS_BOOTMAPSZ and
3257 bootm_mapsize - Size of the initial memory mapping for the Linux kernel.
3258 This variable is given as a hexadecimal number and it
3259 defines the size of the memory region starting at base
3260 address bootm_low that is accessible by the Linux kernel
3261 during early boot. If unset, CONFIG_SYS_BOOTMAPSZ is used
3262 as the default value if it is defined, and bootm_size is
3265 bootm_size - Memory range available for image processing in the bootm
3266 command can be restricted. This variable is given as
3267 a hexadecimal number and defines the size of the region
3268 allowed for use by the bootm command. See also "bootm_low"
3269 environment variable.
3271 updatefile - Location of the software update file on a TFTP server, used
3272 by the automatic software update feature. Please refer to
3273 documentation in doc/README.update for more details.
3275 autoload - if set to "no" (any string beginning with 'n'),
3276 "bootp" will just load perform a lookup of the
3277 configuration from the BOOTP server, but not try to
3278 load any image using TFTP
3280 autostart - if set to "yes", an image loaded using the "bootp",
3281 "rarpboot", "tftpboot" or "diskboot" commands will
3282 be automatically started (by internally calling
3285 If set to "no", a standalone image passed to the
3286 "bootm" command will be copied to the load address
3287 (and eventually uncompressed), but NOT be started.
3288 This can be used to load and uncompress arbitrary
3291 i2cfast - (PPC405GP|PPC405EP only)
3292 if set to 'y' configures Linux I2C driver for fast
3293 mode (400kHZ). This environment variable is used in
3294 initialization code. So, for changes to be effective
3295 it must be saved and board must be reset.
3297 initrd_high - restrict positioning of initrd images:
3298 If this variable is not set, initrd images will be
3299 copied to the highest possible address in RAM; this
3300 is usually what you want since it allows for
3301 maximum initrd size. If for some reason you want to
3302 make sure that the initrd image is loaded below the
3303 CONFIG_SYS_BOOTMAPSZ limit, you can set this environment
3304 variable to a value of "no" or "off" or "0".
3305 Alternatively, you can set it to a maximum upper
3306 address to use (U-Boot will still check that it
3307 does not overwrite the U-Boot stack and data).
3309 For instance, when you have a system with 16 MB
3310 RAM, and want to reserve 4 MB from use by Linux,
3311 you can do this by adding "mem=12M" to the value of
3312 the "bootargs" variable. However, now you must make
3313 sure that the initrd image is placed in the first
3314 12 MB as well - this can be done with
3316 setenv initrd_high 00c00000
3318 If you set initrd_high to 0xFFFFFFFF, this is an
3319 indication to U-Boot that all addresses are legal
3320 for the Linux kernel, including addresses in flash
3321 memory. In this case U-Boot will NOT COPY the
3322 ramdisk at all. This may be useful to reduce the
3323 boot time on your system, but requires that this
3324 feature is supported by your Linux kernel.
3326 ipaddr - IP address; needed for tftpboot command
3328 loadaddr - Default load address for commands like "bootp",
3329 "rarpboot", "tftpboot", "loadb" or "diskboot"
3331 loads_echo - see CONFIG_LOADS_ECHO
3333 serverip - TFTP server IP address; needed for tftpboot command
3335 bootretry - see CONFIG_BOOT_RETRY_TIME
3337 bootdelaykey - see CONFIG_AUTOBOOT_DELAY_STR
3339 bootstopkey - see CONFIG_AUTOBOOT_STOP_STR
3341 ethprime - When CONFIG_NET_MULTI is enabled controls which
3342 interface is used first.
3344 ethact - When CONFIG_NET_MULTI is enabled controls which
3345 interface is currently active. For example you
3346 can do the following
3348 => setenv ethact FEC
3349 => ping 192.168.0.1 # traffic sent on FEC
3350 => setenv ethact SCC
3351 => ping 10.0.0.1 # traffic sent on SCC
3353 ethrotate - When set to "no" U-Boot does not go through all
3354 available network interfaces.
3355 It just stays at the currently selected interface.
3357 netretry - When set to "no" each network operation will
3358 either succeed or fail without retrying.
3359 When set to "once" the network operation will
3360 fail when all the available network interfaces
3361 are tried once without success.
3362 Useful on scripts which control the retry operation
3365 npe_ucode - set load address for the NPE microcode
3367 tftpsrcport - If this is set, the value is used for TFTP's
3370 tftpdstport - If this is set, the value is used for TFTP's UDP
3371 destination port instead of the Well Know Port 69.
3373 tftpblocksize - Block size to use for TFTP transfers; if not set,
3374 we use the TFTP server's default block size
3376 tftptimeout - Retransmission timeout for TFTP packets (in milli-
3377 seconds, minimum value is 1000 = 1 second). Defines
3378 when a packet is considered to be lost so it has to
3379 be retransmitted. The default is 5000 = 5 seconds.
3380 Lowering this value may make downloads succeed
3381 faster in networks with high packet loss rates or
3382 with unreliable TFTP servers.
3384 vlan - When set to a value < 4095 the traffic over
3385 Ethernet is encapsulated/received over 802.1q
3388 The following environment variables may be used and automatically
3389 updated by the network boot commands ("bootp" and "rarpboot"),
3390 depending the information provided by your boot server:
3392 bootfile - see above
3393 dnsip - IP address of your Domain Name Server
3394 dnsip2 - IP address of your secondary Domain Name Server
3395 gatewayip - IP address of the Gateway (Router) to use
3396 hostname - Target hostname
3398 netmask - Subnet Mask
3399 rootpath - Pathname of the root filesystem on the NFS server
3400 serverip - see above
3403 There are two special Environment Variables:
3405 serial# - contains hardware identification information such
3406 as type string and/or serial number
3407 ethaddr - Ethernet address
3409 These variables can be set only once (usually during manufacturing of
3410 the board). U-Boot refuses to delete or overwrite these variables
3411 once they have been set once.
3414 Further special Environment Variables:
3416 ver - Contains the U-Boot version string as printed
3417 with the "version" command. This variable is
3418 readonly (see CONFIG_VERSION_VARIABLE).
3421 Please note that changes to some configuration parameters may take
3422 only effect after the next boot (yes, that's just like Windoze :-).
3425 Command Line Parsing:
3426 =====================
3428 There are two different command line parsers available with U-Boot:
3429 the old "simple" one, and the much more powerful "hush" shell:
3431 Old, simple command line parser:
3432 --------------------------------
3434 - supports environment variables (through setenv / saveenv commands)
3435 - several commands on one line, separated by ';'
3436 - variable substitution using "... ${name} ..." syntax
3437 - special characters ('$', ';') can be escaped by prefixing with '\',
3439 setenv bootcmd bootm \${address}
3440 - You can also escape text by enclosing in single apostrophes, for example:
3441 setenv addip 'setenv bootargs $bootargs ip=$ipaddr:$serverip:$gatewayip:$netmask:$hostname::off'
3446 - similar to Bourne shell, with control structures like
3447 if...then...else...fi, for...do...done; while...do...done,
3448 until...do...done, ...
3449 - supports environment ("global") variables (through setenv / saveenv
3450 commands) and local shell variables (through standard shell syntax
3451 "name=value"); only environment variables can be used with "run"
3457 (1) If a command line (or an environment variable executed by a "run"
3458 command) contains several commands separated by semicolon, and
3459 one of these commands fails, then the remaining commands will be
3462 (2) If you execute several variables with one call to run (i. e.
3463 calling run with a list of variables as arguments), any failing
3464 command will cause "run" to terminate, i. e. the remaining
3465 variables are not executed.
3467 Note for Redundant Ethernet Interfaces:
3468 =======================================
3470 Some boards come with redundant Ethernet interfaces; U-Boot supports
3471 such configurations and is capable of automatic selection of a
3472 "working" interface when needed. MAC assignment works as follows:
3474 Network interfaces are numbered eth0, eth1, eth2, ... Corresponding
3475 MAC addresses can be stored in the environment as "ethaddr" (=>eth0),
3476 "eth1addr" (=>eth1), "eth2addr", ...
3478 If the network interface stores some valid MAC address (for instance
3479 in SROM), this is used as default address if there is NO correspon-
3480 ding setting in the environment; if the corresponding environment
3481 variable is set, this overrides the settings in the card; that means:
3483 o If the SROM has a valid MAC address, and there is no address in the
3484 environment, the SROM's address is used.
3486 o If there is no valid address in the SROM, and a definition in the
3487 environment exists, then the value from the environment variable is
3490 o If both the SROM and the environment contain a MAC address, and
3491 both addresses are the same, this MAC address is used.
3493 o If both the SROM and the environment contain a MAC address, and the
3494 addresses differ, the value from the environment is used and a
3497 o If neither SROM nor the environment contain a MAC address, an error
3500 If Ethernet drivers implement the 'write_hwaddr' function, valid MAC addresses
3501 will be programmed into hardware as part of the initialization process. This
3502 may be skipped by setting the appropriate 'ethmacskip' environment variable.
3503 The naming convention is as follows:
3504 "ethmacskip" (=>eth0), "eth1macskip" (=>eth1) etc.
3509 U-Boot is capable of booting (and performing other auxiliary operations on)
3510 images in two formats:
3512 New uImage format (FIT)
3513 -----------------------
3515 Flexible and powerful format based on Flattened Image Tree -- FIT (similar
3516 to Flattened Device Tree). It allows the use of images with multiple
3517 components (several kernels, ramdisks, etc.), with contents protected by
3518 SHA1, MD5 or CRC32. More details are found in the doc/uImage.FIT directory.
3524 Old image format is based on binary files which can be basically anything,
3525 preceded by a special header; see the definitions in include/image.h for
3526 details; basically, the header defines the following image properties:
3528 * Target Operating System (Provisions for OpenBSD, NetBSD, FreeBSD,
3529 4.4BSD, Linux, SVR4, Esix, Solaris, Irix, SCO, Dell, NCR, VxWorks,
3530 LynxOS, pSOS, QNX, RTEMS, INTEGRITY;
3531 Currently supported: Linux, NetBSD, VxWorks, QNX, RTEMS, LynxOS,
3533 * Target CPU Architecture (Provisions for Alpha, ARM, AVR32, Intel x86,
3534 IA64, MIPS, Nios II, PowerPC, IBM S390, SuperH, Sparc, Sparc 64 Bit;
3535 Currently supported: ARM, AVR32, Intel x86, MIPS, Nios II, PowerPC).
3536 * Compression Type (uncompressed, gzip, bzip2)
3542 The header is marked by a special Magic Number, and both the header
3543 and the data portions of the image are secured against corruption by
3550 Although U-Boot should support any OS or standalone application
3551 easily, the main focus has always been on Linux during the design of
3554 U-Boot includes many features that so far have been part of some
3555 special "boot loader" code within the Linux kernel. Also, any
3556 "initrd" images to be used are no longer part of one big Linux image;
3557 instead, kernel and "initrd" are separate images. This implementation
3558 serves several purposes:
3560 - the same features can be used for other OS or standalone
3561 applications (for instance: using compressed images to reduce the
3562 Flash memory footprint)
3564 - it becomes much easier to port new Linux kernel versions because
3565 lots of low-level, hardware dependent stuff are done by U-Boot
3567 - the same Linux kernel image can now be used with different "initrd"
3568 images; of course this also means that different kernel images can
3569 be run with the same "initrd". This makes testing easier (you don't
3570 have to build a new "zImage.initrd" Linux image when you just
3571 change a file in your "initrd"). Also, a field-upgrade of the
3572 software is easier now.
3578 Porting Linux to U-Boot based systems:
3579 ---------------------------------------
3581 U-Boot cannot save you from doing all the necessary modifications to
3582 configure the Linux device drivers for use with your target hardware
3583 (no, we don't intend to provide a full virtual machine interface to
3586 But now you can ignore ALL boot loader code (in arch/powerpc/mbxboot).
3588 Just make sure your machine specific header file (for instance
3589 include/asm-ppc/tqm8xx.h) includes the same definition of the Board
3590 Information structure as we define in include/asm-<arch>/u-boot.h,
3591 and make sure that your definition of IMAP_ADDR uses the same value
3592 as your U-Boot configuration in CONFIG_SYS_IMMR.
3595 Configuring the Linux kernel:
3596 -----------------------------
3598 No specific requirements for U-Boot. Make sure you have some root
3599 device (initial ramdisk, NFS) for your target system.
3602 Building a Linux Image:
3603 -----------------------
3605 With U-Boot, "normal" build targets like "zImage" or "bzImage" are
3606 not used. If you use recent kernel source, a new build target
3607 "uImage" will exist which automatically builds an image usable by
3608 U-Boot. Most older kernels also have support for a "pImage" target,
3609 which was introduced for our predecessor project PPCBoot and uses a
3610 100% compatible format.
3619 The "uImage" build target uses a special tool (in 'tools/mkimage') to
3620 encapsulate a compressed Linux kernel image with header information,
3621 CRC32 checksum etc. for use with U-Boot. This is what we are doing:
3623 * build a standard "vmlinux" kernel image (in ELF binary format):
3625 * convert the kernel into a raw binary image:
3627 ${CROSS_COMPILE}-objcopy -O binary \
3628 -R .note -R .comment \
3629 -S vmlinux linux.bin
3631 * compress the binary image:
3635 * package compressed binary image for U-Boot:
3637 mkimage -A ppc -O linux -T kernel -C gzip \
3638 -a 0 -e 0 -n "Linux Kernel Image" \
3639 -d linux.bin.gz uImage
3642 The "mkimage" tool can also be used to create ramdisk images for use
3643 with U-Boot, either separated from the Linux kernel image, or
3644 combined into one file. "mkimage" encapsulates the images with a 64
3645 byte header containing information about target architecture,
3646 operating system, image type, compression method, entry points, time
3647 stamp, CRC32 checksums, etc.
3649 "mkimage" can be called in two ways: to verify existing images and
3650 print the header information, or to build new images.
3652 In the first form (with "-l" option) mkimage lists the information
3653 contained in the header of an existing U-Boot image; this includes
3654 checksum verification:
3656 tools/mkimage -l image
3657 -l ==> list image header information
3659 The second form (with "-d" option) is used to build a U-Boot image
3660 from a "data file" which is used as image payload:
3662 tools/mkimage -A arch -O os -T type -C comp -a addr -e ep \
3663 -n name -d data_file image
3664 -A ==> set architecture to 'arch'
3665 -O ==> set operating system to 'os'
3666 -T ==> set image type to 'type'
3667 -C ==> set compression type 'comp'
3668 -a ==> set load address to 'addr' (hex)
3669 -e ==> set entry point to 'ep' (hex)
3670 -n ==> set image name to 'name'
3671 -d ==> use image data from 'datafile'
3673 Right now, all Linux kernels for PowerPC systems use the same load
3674 address (0x00000000), but the entry point address depends on the
3677 - 2.2.x kernels have the entry point at 0x0000000C,
3678 - 2.3.x and later kernels have the entry point at 0x00000000.
3680 So a typical call to build a U-Boot image would read:
3682 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \
3683 > -A ppc -O linux -T kernel -C gzip -a 0 -e 0 \
3684 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux.gz \
3685 > examples/uImage.TQM850L
3686 Image Name: 2.4.4 kernel for TQM850L
3687 Created: Wed Jul 19 02:34:59 2000
3688 Image Type: PowerPC Linux Kernel Image (gzip compressed)
3689 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB
3690 Load Address: 0x00000000
3691 Entry Point: 0x00000000
3693 To verify the contents of the image (or check for corruption):
3695 -> tools/mkimage -l examples/uImage.TQM850L
3696 Image Name: 2.4.4 kernel for TQM850L
3697 Created: Wed Jul 19 02:34:59 2000
3698 Image Type: PowerPC Linux Kernel Image (gzip compressed)
3699 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB
3700 Load Address: 0x00000000
3701 Entry Point: 0x00000000
3703 NOTE: for embedded systems where boot time is critical you can trade
3704 speed for memory and install an UNCOMPRESSED image instead: this
3705 needs more space in Flash, but boots much faster since it does not
3706 need to be uncompressed:
3708 -> gunzip /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux.gz
3709 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \
3710 > -A ppc -O linux -T kernel -C none -a 0 -e 0 \
3711 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux \
3712 > examples/uImage.TQM850L-uncompressed
3713 Image Name: 2.4.4 kernel for TQM850L
3714 Created: Wed Jul 19 02:34:59 2000
3715 Image Type: PowerPC Linux Kernel Image (uncompressed)
3716 Data Size: 792160 Bytes = 773.59 kB = 0.76 MB
3717 Load Address: 0x00000000
3718 Entry Point: 0x00000000
3721 Similar you can build U-Boot images from a 'ramdisk.image.gz' file
3722 when your kernel is intended to use an initial ramdisk:
3724 -> tools/mkimage -n 'Simple Ramdisk Image' \
3725 > -A ppc -O linux -T ramdisk -C gzip \
3726 > -d /LinuxPPC/images/SIMPLE-ramdisk.image.gz examples/simple-initrd
3727 Image Name: Simple Ramdisk Image
3728 Created: Wed Jan 12 14:01:50 2000
3729 Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
3730 Data Size: 566530 Bytes = 553.25 kB = 0.54 MB
3731 Load Address: 0x00000000
3732 Entry Point: 0x00000000
3735 Installing a Linux Image:
3736 -------------------------
3738 To downloading a U-Boot image over the serial (console) interface,
3739 you must convert the image to S-Record format:
3741 objcopy -I binary -O srec examples/image examples/image.srec
3743 The 'objcopy' does not understand the information in the U-Boot
3744 image header, so the resulting S-Record file will be relative to
3745 address 0x00000000. To load it to a given address, you need to
3746 specify the target address as 'offset' parameter with the 'loads'
3749 Example: install the image to address 0x40100000 (which on the
3750 TQM8xxL is in the first Flash bank):
3752 => erase 40100000 401FFFFF
3758 ## Ready for S-Record download ...
3759 ~>examples/image.srec
3760 1 2 3 4 5 6 7 8 9 10 11 12 13 ...
3762 15989 15990 15991 15992
3763 [file transfer complete]
3765 ## Start Addr = 0x00000000
3768 You can check the success of the download using the 'iminfo' command;
3769 this includes a checksum verification so you can be sure no data
3770 corruption happened:
3774 ## Checking Image at 40100000 ...
3775 Image Name: 2.2.13 for initrd on TQM850L
3776 Image Type: PowerPC Linux Kernel Image (gzip compressed)
3777 Data Size: 335725 Bytes = 327 kB = 0 MB
3778 Load Address: 00000000
3779 Entry Point: 0000000c
3780 Verifying Checksum ... OK
3786 The "bootm" command is used to boot an application that is stored in
3787 memory (RAM or Flash). In case of a Linux kernel image, the contents
3788 of the "bootargs" environment variable is passed to the kernel as
3789 parameters. You can check and modify this variable using the
3790 "printenv" and "setenv" commands:
3793 => printenv bootargs
3794 bootargs=root=/dev/ram
3796 => setenv bootargs root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
3798 => printenv bootargs
3799 bootargs=root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
3802 ## Booting Linux kernel at 40020000 ...
3803 Image Name: 2.2.13 for NFS on TQM850L
3804 Image Type: PowerPC Linux Kernel Image (gzip compressed)
3805 Data Size: 381681 Bytes = 372 kB = 0 MB
3806 Load Address: 00000000
3807 Entry Point: 0000000c
3808 Verifying Checksum ... OK
3809 Uncompressing Kernel Image ... OK
3810 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
3811 Boot arguments: root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
3812 time_init: decrementer frequency = 187500000/60
3813 Calibrating delay loop... 49.77 BogoMIPS
3814 Memory: 15208k available (700k kernel code, 444k data, 32k init) [c0000000,c1000000]
3817 If you want to boot a Linux kernel with initial RAM disk, you pass
3818 the memory addresses of both the kernel and the initrd image (PPBCOOT
3819 format!) to the "bootm" command:
3821 => imi 40100000 40200000
3823 ## Checking Image at 40100000 ...
3824 Image Name: 2.2.13 for initrd on TQM850L
3825 Image Type: PowerPC Linux Kernel Image (gzip compressed)
3826 Data Size: 335725 Bytes = 327 kB = 0 MB
3827 Load Address: 00000000
3828 Entry Point: 0000000c
3829 Verifying Checksum ... OK
3831 ## Checking Image at 40200000 ...
3832 Image Name: Simple Ramdisk Image
3833 Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
3834 Data Size: 566530 Bytes = 553 kB = 0 MB
3835 Load Address: 00000000
3836 Entry Point: 00000000
3837 Verifying Checksum ... OK
3839 => bootm 40100000 40200000
3840 ## Booting Linux kernel at 40100000 ...
3841 Image Name: 2.2.13 for initrd on TQM850L
3842 Image Type: PowerPC Linux Kernel Image (gzip compressed)
3843 Data Size: 335725 Bytes = 327 kB = 0 MB
3844 Load Address: 00000000
3845 Entry Point: 0000000c
3846 Verifying Checksum ... OK
3847 Uncompressing Kernel Image ... OK
3848 ## Loading RAMDisk Image at 40200000 ...
3849 Image Name: Simple Ramdisk Image
3850 Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
3851 Data Size: 566530 Bytes = 553 kB = 0 MB
3852 Load Address: 00000000
3853 Entry Point: 00000000
3854 Verifying Checksum ... OK
3855 Loading Ramdisk ... OK
3856 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
3857 Boot arguments: root=/dev/ram
3858 time_init: decrementer frequency = 187500000/60
3859 Calibrating delay loop... 49.77 BogoMIPS
3861 RAMDISK: Compressed image found at block 0
3862 VFS: Mounted root (ext2 filesystem).
3866 Boot Linux and pass a flat device tree:
3869 First, U-Boot must be compiled with the appropriate defines. See the section
3870 titled "Linux Kernel Interface" above for a more in depth explanation. The
3871 following is an example of how to start a kernel and pass an updated
3877 oft=oftrees/mpc8540ads.dtb
3878 => tftp $oftaddr $oft
3879 Speed: 1000, full duplex
3881 TFTP from server 192.168.1.1; our IP address is 192.168.1.101
3882 Filename 'oftrees/mpc8540ads.dtb'.
3883 Load address: 0x300000
3886 Bytes transferred = 4106 (100a hex)
3887 => tftp $loadaddr $bootfile
3888 Speed: 1000, full duplex
3890 TFTP from server 192.168.1.1; our IP address is 192.168.1.2
3892 Load address: 0x200000
3893 Loading:############
3895 Bytes transferred = 1029407 (fb51f hex)
3900 => bootm $loadaddr - $oftaddr
3901 ## Booting image at 00200000 ...
3902 Image Name: Linux-2.6.17-dirty
3903 Image Type: PowerPC Linux Kernel Image (gzip compressed)
3904 Data Size: 1029343 Bytes = 1005.2 kB
3905 Load Address: 00000000
3906 Entry Point: 00000000
3907 Verifying Checksum ... OK
3908 Uncompressing Kernel Image ... OK
3909 Booting using flat device tree at 0x300000
3910 Using MPC85xx ADS machine description
3911 Memory CAM mapping: CAM0=256Mb, CAM1=256Mb, CAM2=0Mb residual: 0Mb
3915 More About U-Boot Image Types:
3916 ------------------------------
3918 U-Boot supports the following image types:
3920 "Standalone Programs" are directly runnable in the environment
3921 provided by U-Boot; it is expected that (if they behave
3922 well) you can continue to work in U-Boot after return from
3923 the Standalone Program.
3924 "OS Kernel Images" are usually images of some Embedded OS which
3925 will take over control completely. Usually these programs
3926 will install their own set of exception handlers, device
3927 drivers, set up the MMU, etc. - this means, that you cannot
3928 expect to re-enter U-Boot except by resetting the CPU.
3929 "RAMDisk Images" are more or less just data blocks, and their
3930 parameters (address, size) are passed to an OS kernel that is
3932 "Multi-File Images" contain several images, typically an OS
3933 (Linux) kernel image and one or more data images like
3934 RAMDisks. This construct is useful for instance when you want
3935 to boot over the network using BOOTP etc., where the boot
3936 server provides just a single image file, but you want to get
3937 for instance an OS kernel and a RAMDisk image.
3939 "Multi-File Images" start with a list of image sizes, each
3940 image size (in bytes) specified by an "uint32_t" in network
3941 byte order. This list is terminated by an "(uint32_t)0".
3942 Immediately after the terminating 0 follow the images, one by
3943 one, all aligned on "uint32_t" boundaries (size rounded up to
3944 a multiple of 4 bytes).
3946 "Firmware Images" are binary images containing firmware (like
3947 U-Boot or FPGA images) which usually will be programmed to
3950 "Script files" are command sequences that will be executed by
3951 U-Boot's command interpreter; this feature is especially
3952 useful when you configure U-Boot to use a real shell (hush)
3953 as command interpreter.
3959 One of the features of U-Boot is that you can dynamically load and
3960 run "standalone" applications, which can use some resources of
3961 U-Boot like console I/O functions or interrupt services.
3963 Two simple examples are included with the sources:
3968 'examples/hello_world.c' contains a small "Hello World" Demo
3969 application; it is automatically compiled when you build U-Boot.
3970 It's configured to run at address 0x00040004, so you can play with it
3974 ## Ready for S-Record download ...
3975 ~>examples/hello_world.srec
3976 1 2 3 4 5 6 7 8 9 10 11 ...
3977 [file transfer complete]
3979 ## Start Addr = 0x00040004
3981 => go 40004 Hello World! This is a test.
3982 ## Starting application at 0x00040004 ...
3993 Hit any key to exit ...
3995 ## Application terminated, rc = 0x0
3997 Another example, which demonstrates how to register a CPM interrupt
3998 handler with the U-Boot code, can be found in 'examples/timer.c'.
3999 Here, a CPM timer is set up to generate an interrupt every second.
4000 The interrupt service routine is trivial, just printing a '.'
4001 character, but this is just a demo program. The application can be
4002 controlled by the following keys:
4004 ? - print current values og the CPM Timer registers
4005 b - enable interrupts and start timer
4006 e - stop timer and disable interrupts
4007 q - quit application
4010 ## Ready for S-Record download ...
4011 ~>examples/timer.srec
4012 1 2 3 4 5 6 7 8 9 10 11 ...
4013 [file transfer complete]
4015 ## Start Addr = 0x00040004
4018 ## Starting application at 0x00040004 ...
4021 tgcr @ 0xfff00980, tmr @ 0xfff00990, trr @ 0xfff00994, tcr @ 0xfff00998, tcn @ 0xfff0099c, ter @ 0xfff009b0
4024 [q, b, e, ?] Set interval 1000000 us
4027 [q, b, e, ?] ........
4028 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0xef6, ter=0x0
4031 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x2ad4, ter=0x0
4034 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x1efc, ter=0x0
4037 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x169d, ter=0x0
4039 [q, b, e, ?] ...Stopping timer
4041 [q, b, e, ?] ## Application terminated, rc = 0x0
4047 Over time, many people have reported problems when trying to use the
4048 "minicom" terminal emulation program for serial download. I (wd)
4049 consider minicom to be broken, and recommend not to use it. Under
4050 Unix, I recommend to use C-Kermit for general purpose use (and
4051 especially for kermit binary protocol download ("loadb" command), and
4052 use "cu" for S-Record download ("loads" command).
4054 Nevertheless, if you absolutely want to use it try adding this
4055 configuration to your "File transfer protocols" section:
4057 Name Program Name U/D FullScr IO-Red. Multi
4058 X kermit /usr/bin/kermit -i -l %l -s Y U Y N N
4059 Y kermit /usr/bin/kermit -i -l %l -r N D Y N N
4065 Starting at version 0.9.2, U-Boot supports NetBSD both as host
4066 (build U-Boot) and target system (boots NetBSD/mpc8xx).
4068 Building requires a cross environment; it is known to work on
4069 NetBSD/i386 with the cross-powerpc-netbsd-1.3 package (you will also
4070 need gmake since the Makefiles are not compatible with BSD make).
4071 Note that the cross-powerpc package does not install include files;
4072 attempting to build U-Boot will fail because <machine/ansi.h> is
4073 missing. This file has to be installed and patched manually:
4075 # cd /usr/pkg/cross/powerpc-netbsd/include
4077 # ln -s powerpc machine
4078 # cp /usr/src/sys/arch/powerpc/include/ansi.h powerpc/ansi.h
4079 # ${EDIT} powerpc/ansi.h ## must remove __va_list, _BSD_VA_LIST
4081 Native builds *don't* work due to incompatibilities between native
4082 and U-Boot include files.
4084 Booting assumes that (the first part of) the image booted is a
4085 stage-2 loader which in turn loads and then invokes the kernel
4086 proper. Loader sources will eventually appear in the NetBSD source
4087 tree (probably in sys/arc/mpc8xx/stand/u-boot_stage2/); in the
4088 meantime, see ftp://ftp.denx.de/pub/u-boot/ppcboot_stage2.tar.gz
4091 Implementation Internals:
4092 =========================
4094 The following is not intended to be a complete description of every
4095 implementation detail. However, it should help to understand the
4096 inner workings of U-Boot and make it easier to port it to custom
4100 Initial Stack, Global Data:
4101 ---------------------------
4103 The implementation of U-Boot is complicated by the fact that U-Boot
4104 starts running out of ROM (flash memory), usually without access to
4105 system RAM (because the memory controller is not initialized yet).
4106 This means that we don't have writable Data or BSS segments, and BSS
4107 is not initialized as zero. To be able to get a C environment working
4108 at all, we have to allocate at least a minimal stack. Implementation
4109 options for this are defined and restricted by the CPU used: Some CPU
4110 models provide on-chip memory (like the IMMR area on MPC8xx and
4111 MPC826x processors), on others (parts of) the data cache can be
4112 locked as (mis-) used as memory, etc.
4114 Chris Hallinan posted a good summary of these issues to the
4115 U-Boot mailing list:
4117 Subject: RE: [U-Boot-Users] RE: More On Memory Bank x (nothingness)?
4118 From: "Chris Hallinan" <clh@net1plus.com>
4119 Date: Mon, 10 Feb 2003 16:43:46 -0500 (22:43 MET)
4122 Correct me if I'm wrong, folks, but the way I understand it
4123 is this: Using DCACHE as initial RAM for Stack, etc, does not
4124 require any physical RAM backing up the cache. The cleverness
4125 is that the cache is being used as a temporary supply of
4126 necessary storage before the SDRAM controller is setup. It's
4127 beyond the scope of this list to explain the details, but you
4128 can see how this works by studying the cache architecture and
4129 operation in the architecture and processor-specific manuals.
4131 OCM is On Chip Memory, which I believe the 405GP has 4K. It
4132 is another option for the system designer to use as an
4133 initial stack/RAM area prior to SDRAM being available. Either
4134 option should work for you. Using CS 4 should be fine if your
4135 board designers haven't used it for something that would
4136 cause you grief during the initial boot! It is frequently not
4139 CONFIG_SYS_INIT_RAM_ADDR should be somewhere that won't interfere
4140 with your processor/board/system design. The default value
4141 you will find in any recent u-boot distribution in
4142 walnut.h should work for you. I'd set it to a value larger
4143 than your SDRAM module. If you have a 64MB SDRAM module, set
4144 it above 400_0000. Just make sure your board has no resources
4145 that are supposed to respond to that address! That code in
4146 start.S has been around a while and should work as is when
4147 you get the config right.
4152 It is essential to remember this, since it has some impact on the C
4153 code for the initialization procedures:
4155 * Initialized global data (data segment) is read-only. Do not attempt
4158 * Do not use any uninitialized global data (or implicitely initialized
4159 as zero data - BSS segment) at all - this is undefined, initiali-
4160 zation is performed later (when relocating to RAM).
4162 * Stack space is very limited. Avoid big data buffers or things like
4165 Having only the stack as writable memory limits means we cannot use
4166 normal global data to share information beween the code. But it
4167 turned out that the implementation of U-Boot can be greatly
4168 simplified by making a global data structure (gd_t) available to all
4169 functions. We could pass a pointer to this data as argument to _all_
4170 functions, but this would bloat the code. Instead we use a feature of
4171 the GCC compiler (Global Register Variables) to share the data: we
4172 place a pointer (gd) to the global data into a register which we
4173 reserve for this purpose.
4175 When choosing a register for such a purpose we are restricted by the
4176 relevant (E)ABI specifications for the current architecture, and by
4177 GCC's implementation.
4179 For PowerPC, the following registers have specific use:
4181 R2: reserved for system use
4182 R3-R4: parameter passing and return values
4183 R5-R10: parameter passing
4184 R13: small data area pointer
4188 (U-Boot also uses R12 as internal GOT pointer. r12
4189 is a volatile register so r12 needs to be reset when
4190 going back and forth between asm and C)
4192 ==> U-Boot will use R2 to hold a pointer to the global data
4194 Note: on PPC, we could use a static initializer (since the
4195 address of the global data structure is known at compile time),
4196 but it turned out that reserving a register results in somewhat
4197 smaller code - although the code savings are not that big (on
4198 average for all boards 752 bytes for the whole U-Boot image,
4199 624 text + 127 data).
4201 On Blackfin, the normal C ABI (except for P3) is followed as documented here:
4202 http://docs.blackfin.uclinux.org/doku.php?id=application_binary_interface
4204 ==> U-Boot will use P3 to hold a pointer to the global data
4206 On ARM, the following registers are used:
4208 R0: function argument word/integer result
4209 R1-R3: function argument word
4211 R10: stack limit (used only if stack checking if enabled)
4212 R11: argument (frame) pointer
4213 R12: temporary workspace
4216 R15: program counter
4218 ==> U-Boot will use R8 to hold a pointer to the global data
4220 On Nios II, the ABI is documented here:
4221 http://www.altera.com/literature/hb/nios2/n2cpu_nii51016.pdf
4223 ==> U-Boot will use gp to hold a pointer to the global data
4225 Note: on Nios II, we give "-G0" option to gcc and don't use gp
4226 to access small data sections, so gp is free.
4228 NOTE: DECLARE_GLOBAL_DATA_PTR must be used with file-global scope,
4229 or current versions of GCC may "optimize" the code too much.
4234 U-Boot runs in system state and uses physical addresses, i.e. the
4235 MMU is not used either for address mapping nor for memory protection.
4237 The available memory is mapped to fixed addresses using the memory
4238 controller. In this process, a contiguous block is formed for each
4239 memory type (Flash, SDRAM, SRAM), even when it consists of several
4240 physical memory banks.
4242 U-Boot is installed in the first 128 kB of the first Flash bank (on
4243 TQM8xxL modules this is the range 0x40000000 ... 0x4001FFFF). After
4244 booting and sizing and initializing DRAM, the code relocates itself
4245 to the upper end of DRAM. Immediately below the U-Boot code some
4246 memory is reserved for use by malloc() [see CONFIG_SYS_MALLOC_LEN
4247 configuration setting]. Below that, a structure with global Board
4248 Info data is placed, followed by the stack (growing downward).
4250 Additionally, some exception handler code is copied to the low 8 kB
4251 of DRAM (0x00000000 ... 0x00001FFF).
4253 So a typical memory configuration with 16 MB of DRAM could look like
4256 0x0000 0000 Exception Vector code
4259 0x0000 2000 Free for Application Use
4265 0x00FB FF20 Monitor Stack (Growing downward)
4266 0x00FB FFAC Board Info Data and permanent copy of global data
4267 0x00FC 0000 Malloc Arena
4270 0x00FE 0000 RAM Copy of Monitor Code
4271 ... eventually: LCD or video framebuffer
4272 ... eventually: pRAM (Protected RAM - unchanged by reset)
4273 0x00FF FFFF [End of RAM]
4276 System Initialization:
4277 ----------------------
4279 In the reset configuration, U-Boot starts at the reset entry point
4280 (on most PowerPC systems at address 0x00000100). Because of the reset
4281 configuration for CS0# this is a mirror of the onboard Flash memory.
4282 To be able to re-map memory U-Boot then jumps to its link address.
4283 To be able to implement the initialization code in C, a (small!)
4284 initial stack is set up in the internal Dual Ported RAM (in case CPUs
4285 which provide such a feature like MPC8xx or MPC8260), or in a locked
4286 part of the data cache. After that, U-Boot initializes the CPU core,
4287 the caches and the SIU.
4289 Next, all (potentially) available memory banks are mapped using a
4290 preliminary mapping. For example, we put them on 512 MB boundaries
4291 (multiples of 0x20000000: SDRAM on 0x00000000 and 0x20000000, Flash
4292 on 0x40000000 and 0x60000000, SRAM on 0x80000000). Then UPM A is
4293 programmed for SDRAM access. Using the temporary configuration, a
4294 simple memory test is run that determines the size of the SDRAM
4297 When there is more than one SDRAM bank, and the banks are of
4298 different size, the largest is mapped first. For equal size, the first
4299 bank (CS2#) is mapped first. The first mapping is always for address
4300 0x00000000, with any additional banks following immediately to create
4301 contiguous memory starting from 0.
4303 Then, the monitor installs itself at the upper end of the SDRAM area
4304 and allocates memory for use by malloc() and for the global Board
4305 Info data; also, the exception vector code is copied to the low RAM
4306 pages, and the final stack is set up.
4308 Only after this relocation will you have a "normal" C environment;
4309 until that you are restricted in several ways, mostly because you are
4310 running from ROM, and because the code will have to be relocated to a
4314 U-Boot Porting Guide:
4315 ----------------------
4317 [Based on messages by Jerry Van Baren in the U-Boot-Users mailing
4321 int main(int argc, char *argv[])
4323 sighandler_t no_more_time;
4325 signal(SIGALRM, no_more_time);
4326 alarm(PROJECT_DEADLINE - toSec (3 * WEEK));
4328 if (available_money > available_manpower) {
4329 Pay consultant to port U-Boot;
4333 Download latest U-Boot source;
4335 Subscribe to u-boot mailing list;
4338 email("Hi, I am new to U-Boot, how do I get started?");
4341 Read the README file in the top level directory;
4342 Read http://www.denx.de/twiki/bin/view/DULG/Manual;
4343 Read applicable doc/*.README;
4344 Read the source, Luke;
4345 /* find . -name "*.[chS]" | xargs grep -i <keyword> */
4348 if (available_money > toLocalCurrency ($2500))
4351 Add a lot of aggravation and time;
4353 if (a similar board exists) { /* hopefully... */
4354 cp -a board/<similar> board/<myboard>
4355 cp include/configs/<similar>.h include/configs/<myboard>.h
4357 Create your own board support subdirectory;
4358 Create your own board include/configs/<myboard>.h file;
4360 Edit new board/<myboard> files
4361 Edit new include/configs/<myboard>.h
4366 Add / modify source code;
4370 email("Hi, I am having problems...");
4372 Send patch file to the U-Boot email list;
4373 if (reasonable critiques)
4374 Incorporate improvements from email list code review;
4376 Defend code as written;
4382 void no_more_time (int sig)
4391 All contributions to U-Boot should conform to the Linux kernel
4392 coding style; see the file "Documentation/CodingStyle" and the script
4393 "scripts/Lindent" in your Linux kernel source directory. In sources
4394 originating from U-Boot a style corresponding to "Lindent -pcs" (adding
4395 spaces before parameters to function calls) is actually used.
4397 Source files originating from a different project (for example the
4398 MTD subsystem) are generally exempt from these guidelines and are not
4399 reformated to ease subsequent migration to newer versions of those
4402 Please note that U-Boot is implemented in C (and to some small parts in
4403 Assembler); no C++ is used, so please do not use C++ style comments (//)
4406 Please also stick to the following formatting rules:
4407 - remove any trailing white space
4408 - use TAB characters for indentation, not spaces
4409 - make sure NOT to use DOS '\r\n' line feeds
4410 - do not add more than 2 empty lines to source files
4411 - do not add trailing empty lines to source files
4413 Submissions which do not conform to the standards may be returned
4414 with a request to reformat the changes.
4420 Since the number of patches for U-Boot is growing, we need to
4421 establish some rules. Submissions which do not conform to these rules
4422 may be rejected, even when they contain important and valuable stuff.
4424 Please see http://www.denx.de/wiki/U-Boot/Patches for details.
4426 Patches shall be sent to the u-boot mailing list <u-boot@lists.denx.de>;
4427 see http://lists.denx.de/mailman/listinfo/u-boot
4429 When you send a patch, please include the following information with
4432 * For bug fixes: a description of the bug and how your patch fixes
4433 this bug. Please try to include a way of demonstrating that the
4434 patch actually fixes something.
4436 * For new features: a description of the feature and your
4439 * A CHANGELOG entry as plaintext (separate from the patch)
4441 * For major contributions, your entry to the CREDITS file
4443 * When you add support for a new board, don't forget to add this
4444 board to the MAKEALL script, too.
4446 * If your patch adds new configuration options, don't forget to
4447 document these in the README file.
4449 * The patch itself. If you are using git (which is *strongly*
4450 recommended) you can easily generate the patch using the
4451 "git-format-patch". If you then use "git-send-email" to send it to
4452 the U-Boot mailing list, you will avoid most of the common problems
4453 with some other mail clients.
4455 If you cannot use git, use "diff -purN OLD NEW". If your version of
4456 diff does not support these options, then get the latest version of
4459 The current directory when running this command shall be the parent
4460 directory of the U-Boot source tree (i. e. please make sure that
4461 your patch includes sufficient directory information for the
4464 We prefer patches as plain text. MIME attachments are discouraged,
4465 and compressed attachments must not be used.
4467 * If one logical set of modifications affects or creates several
4468 files, all these changes shall be submitted in a SINGLE patch file.
4470 * Changesets that contain different, unrelated modifications shall be
4471 submitted as SEPARATE patches, one patch per changeset.
4476 * Before sending the patch, run the MAKEALL script on your patched
4477 source tree and make sure that no errors or warnings are reported
4478 for any of the boards.
4480 * Keep your modifications to the necessary minimum: A patch
4481 containing several unrelated changes or arbitrary reformats will be
4482 returned with a request to re-formatting / split it.
4484 * If you modify existing code, make sure that your new code does not
4485 add to the memory footprint of the code ;-) Small is beautiful!
4486 When adding new features, these should compile conditionally only
4487 (using #ifdef), and the resulting code with the new feature
4488 disabled must not need more memory than the old code without your
4491 * Remember that there is a size limit of 100 kB per message on the
4492 u-boot mailing list. Bigger patches will be moderated. If they are
4493 reasonable and not too big, they will be acknowledged. But patches
4494 bigger than the size limit should be avoided.
projects / karo-tx-uboot.git / blob