2 # (C) Copyright 2000 - 2005
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.
60 In case you have questions about, problems with or contributions for
61 U-Boot you should send a message to the U-Boot mailing list at
62 <u-boot-users@lists.sourceforge.net>. There is also an archive of
63 previous traffic on the mailing list - please search the archive
64 before asking FAQ's. Please see
65 http://lists.sourceforge.net/lists/listinfo/u-boot-users/
71 - start from 8xxrom sources
72 - create PPCBoot project (http://sourceforge.net/projects/ppcboot)
74 - make it easier to add custom boards
75 - make it possible to add other [PowerPC] CPUs
76 - extend functions, especially:
77 * Provide extended interface to Linux boot loader
80 * PCMCIA / CompactFLash / ATA disk / SCSI ... boot
81 - create ARMBoot project (http://sourceforge.net/projects/armboot)
82 - add other CPU families (starting with ARM)
83 - create U-Boot project (http://sourceforge.net/projects/u-boot)
89 The "official" name of this project is "Das U-Boot". The spelling
90 "U-Boot" shall be used in all written text (documentation, comments
91 in source files etc.). Example:
93 This is the README file for the U-Boot project.
95 File names etc. shall be based on the string "u-boot". Examples:
97 include/asm-ppc/u-boot.h
99 #include <asm/u-boot.h>
101 Variable names, preprocessor constants etc. shall be either based on
102 the string "u_boot" or on "U_BOOT". Example:
104 U_BOOT_VERSION u_boot_logo
105 IH_OS_U_BOOT u_boot_hush_start
111 U-Boot uses a 3 level version number containing a version, a
112 sub-version, and a patchlevel: "U-Boot-2.34.5" means version "2",
113 sub-version "34", and patchlevel "4".
115 The patchlevel is used to indicate certain stages of development
116 between released versions, i. e. officially released versions of
117 U-Boot will always have a patchlevel of "0".
123 - board Board dependent files
124 - common Misc architecture independent functions
125 - cpu CPU specific files
126 - 74xx_7xx Files specific to Freescale MPC74xx and 7xx CPUs
127 - arm720t Files specific to ARM 720 CPUs
128 - arm920t Files specific to ARM 920 CPUs
129 - at91rm9200 Files specific to Atmel AT91RM9200 CPU
130 - imx Files specific to Freescale MC9328 i.MX CPUs
131 - s3c24x0 Files specific to Samsung S3C24X0 CPUs
132 - arm925t Files specific to ARM 925 CPUs
133 - arm926ejs Files specific to ARM 926 CPUs
134 - arm1136 Files specific to ARM 1136 CPUs
135 - i386 Files specific to i386 CPUs
136 - ixp Files specific to Intel XScale IXP CPUs
137 - mcf52x2 Files specific to Freescale ColdFire MCF52x2 CPUs
138 - mips Files specific to MIPS CPUs
139 - mpc5xx Files specific to Freescale MPC5xx CPUs
140 - mpc5xxx Files specific to Freescale MPC5xxx CPUs
141 - mpc8xx Files specific to Freescale MPC8xx CPUs
142 - mpc8220 Files specific to Freescale MPC8220 CPUs
143 - mpc824x Files specific to Freescale MPC824x CPUs
144 - mpc8260 Files specific to Freescale MPC8260 CPUs
145 - mpc85xx Files specific to Freescale MPC85xx CPUs
146 - nios Files specific to Altera NIOS CPUs
147 - nios2 Files specific to Altera Nios-II CPUs
148 - ppc4xx Files specific to IBM PowerPC 4xx CPUs
149 - pxa Files specific to Intel XScale PXA CPUs
150 - s3c44b0 Files specific to Samsung S3C44B0 CPUs
151 - sa1100 Files specific to Intel StrongARM SA1100 CPUs
152 - disk Code for disk drive partition handling
153 - doc Documentation (don't expect too much)
154 - drivers Commonly used device drivers
155 - dtt Digital Thermometer and Thermostat drivers
156 - examples Example code for standalone applications, etc.
157 - include Header Files
158 - lib_arm Files generic to ARM architecture
159 - lib_generic Files generic to all architectures
160 - lib_i386 Files generic to i386 architecture
161 - lib_m68k Files generic to m68k architecture
162 - lib_mips Files generic to MIPS architecture
163 - lib_nios Files generic to NIOS architecture
164 - lib_ppc Files generic to PowerPC architecture
165 - net Networking code
166 - post Power On Self Test
167 - rtc Real Time Clock drivers
168 - tools Tools to build S-Record or U-Boot images, etc.
170 Software Configuration:
171 =======================
173 Configuration is usually done using C preprocessor defines; the
174 rationale behind that is to avoid dead code whenever possible.
176 There are two classes of configuration variables:
178 * Configuration _OPTIONS_:
179 These are selectable by the user and have names beginning with
182 * Configuration _SETTINGS_:
183 These depend on the hardware etc. and should not be meddled with if
184 you don't know what you're doing; they have names beginning with
187 Later we will add a configuration tool - probably similar to or even
188 identical to what's used for the Linux kernel. Right now, we have to
189 do the configuration by hand, which means creating some symbolic
190 links and editing some configuration files. We use the TQM8xxL boards
194 Selection of Processor Architecture and Board Type:
195 ---------------------------------------------------
197 For all supported boards there are ready-to-use default
198 configurations available; just type "make <board_name>_config".
200 Example: For a TQM823L module type:
205 For the Cogent platform, you need to specify the cpu type as well;
206 e.g. "make cogent_mpc8xx_config". And also configure the cogent
207 directory according to the instructions in cogent/README.
210 Configuration Options:
211 ----------------------
213 Configuration depends on the combination of board and CPU type; all
214 such information is kept in a configuration file
215 "include/configs/<board_name>.h".
217 Example: For a TQM823L module, all configuration settings are in
218 "include/configs/TQM823L.h".
221 Many of the options are named exactly as the corresponding Linux
222 kernel configuration options. The intention is to make it easier to
223 build a config tool - later.
226 The following options need to be configured:
228 - CPU Type: Define exactly one of
232 CONFIG_MPC823, CONFIG_MPC850, CONFIG_MPC855, CONFIG_MPC860
235 or CONFIG_MPC824X, CONFIG_MPC8260
250 MicroBlaze based CPUs:
251 ----------------------
255 ----------------------
259 - Board Type: Define exactly one of
261 PowerPC based boards:
262 ---------------------
264 CONFIG_ADCIOP CONFIG_GEN860T CONFIG_PCI405
265 CONFIG_ADS860 CONFIG_GENIETV CONFIG_PCIPPC2
266 CONFIG_AMX860 CONFIG_GTH CONFIG_PCIPPC6
267 CONFIG_AR405 CONFIG_gw8260 CONFIG_pcu_e
268 CONFIG_BAB7xx CONFIG_hermes CONFIG_PIP405
269 CONFIG_c2mon CONFIG_hymod CONFIG_PM826
270 CONFIG_CANBT CONFIG_IAD210 CONFIG_ppmc8260
271 CONFIG_CCM CONFIG_ICU862 CONFIG_QS823
272 CONFIG_CMI CONFIG_IP860 CONFIG_QS850
273 CONFIG_cogent_mpc8260 CONFIG_IPHASE4539 CONFIG_QS860T
274 CONFIG_cogent_mpc8xx CONFIG_IVML24 CONFIG_RBC823
275 CONFIG_CPCI405 CONFIG_IVML24_128 CONFIG_RPXClassic
276 CONFIG_CPCI4052 CONFIG_IVML24_256 CONFIG_RPXlite
277 CONFIG_CPCIISER4 CONFIG_IVMS8 CONFIG_RPXsuper
278 CONFIG_CPU86 CONFIG_IVMS8_128 CONFIG_rsdproto
279 CONFIG_CRAYL1 CONFIG_IVMS8_256 CONFIG_sacsng
280 CONFIG_CSB272 CONFIG_JSE CONFIG_Sandpoint8240
281 CONFIG_CU824 CONFIG_LANTEC CONFIG_Sandpoint8245
282 CONFIG_DASA_SIM CONFIG_lwmon CONFIG_sbc8260
283 CONFIG_DB64360 CONFIG_MBX CONFIG_sbc8560
284 CONFIG_DB64460 CONFIG_MBX860T CONFIG_SM850
285 CONFIG_DU405 CONFIG_MHPC CONFIG_SPD823TS
286 CONFIG_DUET_ADS CONFIG_MIP405 CONFIG_STXGP3
287 CONFIG_EBONY CONFIG_MOUSSE CONFIG_SXNI855T
288 CONFIG_ELPPC CONFIG_MPC8260ADS CONFIG_TQM823L
289 CONFIG_ELPT860 CONFIG_MPC8540ADS CONFIG_TQM8260
290 CONFIG_ep8260 CONFIG_MPC8540EVAL CONFIG_TQM850L
291 CONFIG_ERIC CONFIG_MPC8560ADS CONFIG_TQM855L
292 CONFIG_ESTEEM192E CONFIG_MUSENKI CONFIG_TQM860L
293 CONFIG_ETX094 CONFIG_MVS1 CONFIG_TTTech
294 CONFIG_EVB64260 CONFIG_NETPHONE CONFIG_UTX8245
295 CONFIG_FADS823 CONFIG_NETTA CONFIG_V37
296 CONFIG_FADS850SAR CONFIG_NETVIA CONFIG_W7OLMC
297 CONFIG_FADS860T CONFIG_NX823 CONFIG_W7OLMG
298 CONFIG_FLAGADM CONFIG_OCRTC CONFIG_WALNUT
299 CONFIG_FPS850L CONFIG_ORSG CONFIG_ZPC1900
300 CONFIG_FPS860L CONFIG_OXC CONFIG_ZUMA
305 CONFIG_AT91RM9200DK, CONFIG_CERF250, CONFIG_DNP1110,
306 CONFIG_EP7312, CONFIG_H2_OMAP1610, CONFIG_HHP_CRADLE,
307 CONFIG_IMPA7, CONFIG_INNOVATOROMAP1510, CONFIG_INNOVATOROMAP1610,
308 CONFIG_LART, CONFIG_LPD7A400 CONFIG_LUBBOCK,
309 CONFIG_OSK_OMAP5912, CONFIG_OMAP2420H4, CONFIG_SHANNON,
310 CONFIG_P2_OMAP730, CONFIG_SMDK2400, CONFIG_SMDK2410,
311 CONFIG_TRAB, CONFIG_VCMA9
313 MicroBlaze based boards:
314 ------------------------
319 ------------------------
321 CONFIG_PCI5441 CONFIG_PK1C20
324 - CPU Module Type: (if CONFIG_COGENT is defined)
325 Define exactly one of
327 --- FIXME --- not tested yet:
328 CONFIG_CMA286_60, CONFIG_CMA286_21, CONFIG_CMA286_60P,
329 CONFIG_CMA287_23, CONFIG_CMA287_50
331 - Motherboard Type: (if CONFIG_COGENT is defined)
332 Define exactly one of
333 CONFIG_CMA101, CONFIG_CMA102
335 - Motherboard I/O Modules: (if CONFIG_COGENT is defined)
336 Define one or more of
339 - Motherboard Options: (if CONFIG_CMA101 or CONFIG_CMA102 are defined)
340 Define one or more of
341 CONFIG_LCD_HEARTBEAT - update a character position on
342 the lcd display every second with
345 - Board flavour: (if CONFIG_MPC8260ADS is defined)
348 CFG_8260ADS - original MPC8260ADS
349 CFG_8266ADS - MPC8266ADS
350 CFG_PQ2FADS - PQ2FADS-ZU or PQ2FADS-VR
351 CFG_8272ADS - MPC8272ADS
353 - MPC824X Family Member (if CONFIG_MPC824X is defined)
354 Define exactly one of
355 CONFIG_MPC8240, CONFIG_MPC8245
357 - 8xx CPU Options: (if using an MPC8xx cpu)
358 CONFIG_8xx_GCLK_FREQ - deprecated: CPU clock if
359 get_gclk_freq() cannot work
360 e.g. if there is no 32KHz
361 reference PIT/RTC clock
362 CONFIG_8xx_OSCLK - PLL input clock (either EXTCLK
365 - 859/866/885 CPU options: (if using a MPC859 or MPC866 or MPC885 CPU):
368 CONFIG_8xx_CPUCLK_DEFAULT
369 See doc/README.MPC866
373 Define this to measure the actual CPU clock instead
374 of relying on the correctness of the configured
375 values. Mostly useful for board bringup to make sure
376 the PLL is locked at the intended frequency. Note
377 that this requires a (stable) reference clock (32 kHz
378 RTC clock or CFG_8XX_XIN)
380 - Linux Kernel Interface:
383 U-Boot stores all clock information in Hz
384 internally. For binary compatibility with older Linux
385 kernels (which expect the clocks passed in the
386 bd_info data to be in MHz) the environment variable
387 "clocks_in_mhz" can be defined so that U-Boot
388 converts clock data to MHZ before passing it to the
390 When CONFIG_CLOCKS_IN_MHZ is defined, a definition of
391 "clocks_in_mhz=1" is automatically included in the
394 CONFIG_MEMSIZE_IN_BYTES [relevant for MIPS only]
396 When transfering memsize parameter to linux, some versions
397 expect it to be in bytes, others in MB.
398 Define CONFIG_MEMSIZE_IN_BYTES to make it in bytes.
403 Define this if you want support for Amba PrimeCell PL010 UARTs.
407 Define this if you want support for Amba PrimeCell PL011 UARTs.
411 If you have Amba PrimeCell PL011 UARTs, set this variable to
412 the clock speed of the UARTs.
416 If you have Amba PrimeCell PL010 or PL011 UARTs on your board,
417 define this to a list of base addresses for each (supported)
418 port. See e.g. include/configs/versatile.h
422 Depending on board, define exactly one serial port
423 (like CONFIG_8xx_CONS_SMC1, CONFIG_8xx_CONS_SMC2,
424 CONFIG_8xx_CONS_SCC1, ...), or switch off the serial
425 console by defining CONFIG_8xx_CONS_NONE
427 Note: if CONFIG_8xx_CONS_NONE is defined, the serial
428 port routines must be defined elsewhere
429 (i.e. serial_init(), serial_getc(), ...)
432 Enables console device for a color framebuffer. Needs following
433 defines (cf. smiLynxEM, i8042, board/eltec/bab7xx)
434 VIDEO_FB_LITTLE_ENDIAN graphic memory organisation
436 VIDEO_HW_RECTFILL graphic chip supports
439 VIDEO_HW_BITBLT graphic chip supports
440 bit-blit (cf. smiLynxEM)
441 VIDEO_VISIBLE_COLS visible pixel columns
443 VIDEO_VISIBLE_ROWS visible pixel rows
444 VIDEO_PIXEL_SIZE bytes per pixel
445 VIDEO_DATA_FORMAT graphic data format
446 (0-5, cf. cfb_console.c)
447 VIDEO_FB_ADRS framebuffer address
448 VIDEO_KBD_INIT_FCT keyboard int fct
449 (i.e. i8042_kbd_init())
450 VIDEO_TSTC_FCT test char fct
452 VIDEO_GETC_FCT get char fct
454 CONFIG_CONSOLE_CURSOR cursor drawing on/off
455 (requires blink timer
457 CFG_CONSOLE_BLINK_COUNT blink interval (cf. i8042.c)
458 CONFIG_CONSOLE_TIME display time/date info in
460 (requires CFG_CMD_DATE)
461 CONFIG_VIDEO_LOGO display Linux logo in
463 CONFIG_VIDEO_BMP_LOGO use bmp_logo.h instead of
464 linux_logo.h for logo.
465 Requires CONFIG_VIDEO_LOGO
466 CONFIG_CONSOLE_EXTRA_INFO
467 addional board info beside
470 When CONFIG_CFB_CONSOLE is defined, video console is
471 default i/o. Serial console can be forced with
472 environment 'console=serial'.
474 When CONFIG_SILENT_CONSOLE is defined, all console
475 messages (by U-Boot and Linux!) can be silenced with
476 the "silent" environment variable. See
477 doc/README.silent for more information.
480 CONFIG_BAUDRATE - in bps
481 Select one of the baudrates listed in
482 CFG_BAUDRATE_TABLE, see below.
483 CFG_BRGCLK_PRESCALE, baudrate prescale
485 - Interrupt driven serial port input:
486 CONFIG_SERIAL_SOFTWARE_FIFO
489 Use an interrupt handler for receiving data on the
490 serial port. It also enables using hardware handshake
491 (RTS/CTS) and UART's built-in FIFO. Set the number of
492 bytes the interrupt driven input buffer should have.
494 Leave undefined to disable this feature, including
495 disable the buffer and hardware handshake.
497 - Console UART Number:
501 If defined internal UART1 (and not UART0) is used
502 as default U-Boot console.
504 - Boot Delay: CONFIG_BOOTDELAY - in seconds
505 Delay before automatically booting the default image;
506 set to -1 to disable autoboot.
508 See doc/README.autoboot for these options that
509 work with CONFIG_BOOTDELAY. None are required.
510 CONFIG_BOOT_RETRY_TIME
511 CONFIG_BOOT_RETRY_MIN
512 CONFIG_AUTOBOOT_KEYED
513 CONFIG_AUTOBOOT_PROMPT
514 CONFIG_AUTOBOOT_DELAY_STR
515 CONFIG_AUTOBOOT_STOP_STR
516 CONFIG_AUTOBOOT_DELAY_STR2
517 CONFIG_AUTOBOOT_STOP_STR2
518 CONFIG_ZERO_BOOTDELAY_CHECK
519 CONFIG_RESET_TO_RETRY
523 Only needed when CONFIG_BOOTDELAY is enabled;
524 define a command string that is automatically executed
525 when no character is read on the console interface
526 within "Boot Delay" after reset.
529 This can be used to pass arguments to the bootm
530 command. The value of CONFIG_BOOTARGS goes into the
531 environment value "bootargs".
533 CONFIG_RAMBOOT and CONFIG_NFSBOOT
534 The value of these goes into the environment as
535 "ramboot" and "nfsboot" respectively, and can be used
536 as a convenience, when switching between booting from
542 When this option is #defined, the existence of the
543 environment variable "preboot" will be checked
544 immediately before starting the CONFIG_BOOTDELAY
545 countdown and/or running the auto-boot command resp.
546 entering interactive mode.
548 This feature is especially useful when "preboot" is
549 automatically generated or modified. For an example
550 see the LWMON board specific code: here "preboot" is
551 modified when the user holds down a certain
552 combination of keys on the (special) keyboard when
555 - Serial Download Echo Mode:
557 If defined to 1, all characters received during a
558 serial download (using the "loads" command) are
559 echoed back. This might be needed by some terminal
560 emulations (like "cu"), but may as well just take
561 time on others. This setting #define's the initial
562 value of the "loads_echo" environment variable.
564 - Kgdb Serial Baudrate: (if CFG_CMD_KGDB is defined)
566 Select one of the baudrates listed in
567 CFG_BAUDRATE_TABLE, see below.
571 Most monitor functions can be selected (or
572 de-selected) by adjusting the definition of
573 CONFIG_COMMANDS; to select individual functions,
574 #define CONFIG_COMMANDS by "OR"ing any of the
577 #define enables commands:
578 -------------------------
579 CFG_CMD_ASKENV * ask for env variable
580 CFG_CMD_AUTOSCRIPT Autoscript Support
582 CFG_CMD_BEDBUG * Include BedBug Debugger
583 CFG_CMD_BMP * BMP support
584 CFG_CMD_BSP * Board specific commands
586 CFG_CMD_CACHE * icache, dcache
587 CFG_CMD_CONSOLE coninfo
588 CFG_CMD_DATE * support for RTC, date/time...
589 CFG_CMD_DHCP * DHCP support
590 CFG_CMD_DIAG * Diagnostics
591 CFG_CMD_DOC * Disk-On-Chip Support
592 CFG_CMD_DTT * Digital Therm and Thermostat
593 CFG_CMD_ECHO * echo arguments
594 CFG_CMD_EEPROM * EEPROM read/write support
595 CFG_CMD_ELF * bootelf, bootvx
597 CFG_CMD_FDC * Floppy Disk Support
598 CFG_CMD_FAT * FAT partition support
599 CFG_CMD_FDOS * Dos diskette Support
600 CFG_CMD_FLASH flinfo, erase, protect
601 CFG_CMD_FPGA FPGA device initialization support
602 CFG_CMD_HWFLOW * RTS/CTS hw flow control
603 CFG_CMD_I2C * I2C serial bus support
604 CFG_CMD_IDE * IDE harddisk support
606 CFG_CMD_IMLS List all found images
607 CFG_CMD_IMMAP * IMMR dump support
608 CFG_CMD_IRQ * irqinfo
609 CFG_CMD_ITEST Integer/string test of 2 values
610 CFG_CMD_JFFS2 * JFFS2 Support
614 CFG_CMD_MEMORY md, mm, nm, mw, cp, cmp, crc, base,
616 CFG_CMD_MISC Misc functions like sleep etc
617 CFG_CMD_MMC * MMC memory mapped support
618 CFG_CMD_MII * MII utility commands
619 CFG_CMD_NAND * NAND support
620 CFG_CMD_NET bootp, tftpboot, rarpboot
621 CFG_CMD_PCI * pciinfo
622 CFG_CMD_PCMCIA * PCMCIA support
623 CFG_CMD_PING * send ICMP ECHO_REQUEST to network host
624 CFG_CMD_PORTIO * Port I/O
625 CFG_CMD_REGINFO * Register dump
626 CFG_CMD_RUN run command in env variable
627 CFG_CMD_SAVES * save S record dump
628 CFG_CMD_SCSI * SCSI Support
629 CFG_CMD_SDRAM * print SDRAM configuration information
630 (requires CFG_CMD_I2C)
631 CFG_CMD_SETGETDCR Support for DCR Register access (4xx only)
632 CFG_CMD_SPI * SPI serial bus support
633 CFG_CMD_USB * USB support
634 CFG_CMD_VFD * VFD support (TRAB)
635 CFG_CMD_BSP * Board SPecific functions
636 CFG_CMD_CDP * Cisco Discover Protocol support
637 -----------------------------------------------
640 CONFIG_CMD_DFL Default configuration; at the moment
641 this is includes all commands, except
642 the ones marked with "*" in the list
645 If you don't define CONFIG_COMMANDS it defaults to
646 CONFIG_CMD_DFL in include/cmd_confdefs.h. A board can
647 override the default settings in the respective
650 EXAMPLE: If you want all functions except of network
651 support you can write:
653 #define CONFIG_COMMANDS (CFG_CMD_ALL & ~CFG_CMD_NET)
656 Note: Don't enable the "icache" and "dcache" commands
657 (configuration option CFG_CMD_CACHE) unless you know
658 what you (and your U-Boot users) are doing. Data
659 cache cannot be enabled on systems like the 8xx or
660 8260 (where accesses to the IMMR region must be
661 uncached), and it cannot be disabled on all other
662 systems where we (mis-) use the data cache to hold an
663 initial stack and some data.
666 XXX - this list needs to get updated!
670 If this variable is defined, it enables watchdog
671 support. There must be support in the platform specific
672 code for a watchdog. For the 8xx and 8260 CPUs, the
673 SIU Watchdog feature is enabled in the SYPCR
677 CONFIG_VERSION_VARIABLE
678 If this variable is defined, an environment variable
679 named "ver" is created by U-Boot showing the U-Boot
680 version as printed by the "version" command.
681 This variable is readonly.
685 When CFG_CMD_DATE is selected, the type of the RTC
686 has to be selected, too. Define exactly one of the
689 CONFIG_RTC_MPC8xx - use internal RTC of MPC8xx
690 CONFIG_RTC_PCF8563 - use Philips PCF8563 RTC
691 CONFIG_RTC_MC146818 - use MC146818 RTC
692 CONFIG_RTC_DS1307 - use Maxim, Inc. DS1307 RTC
693 CONFIG_RTC_DS1337 - use Maxim, Inc. DS1337 RTC
694 CONFIG_RTC_DS1338 - use Maxim, Inc. DS1338 RTC
695 CONFIG_RTC_DS164x - use Dallas DS164x RTC
696 CONFIG_RTC_MAX6900 - use Maxim, Inc. MAX6900 RTC
698 Note that if the RTC uses I2C, then the I2C interface
699 must also be configured. See I2C Support, below.
703 When CONFIG_TIMESTAMP is selected, the timestamp
704 (date and time) of an image is printed by image
705 commands like bootm or iminfo. This option is
706 automatically enabled when you select CFG_CMD_DATE .
709 CONFIG_MAC_PARTITION and/or CONFIG_DOS_PARTITION
710 and/or CONFIG_ISO_PARTITION
712 If IDE or SCSI support is enabled (CFG_CMD_IDE or
713 CFG_CMD_SCSI) you must configure support for at least
714 one partition type as well.
717 CONFIG_IDE_RESET_ROUTINE - this is defined in several
718 board configurations files but used nowhere!
720 CONFIG_IDE_RESET - is this is defined, IDE Reset will
721 be performed by calling the function
722 ide_set_reset(int reset)
723 which has to be defined in a board specific file
728 Set this to enable ATAPI support.
733 Set this to enable support for disks larger than 137GB
734 Also look at CFG_64BIT_LBA ,CFG_64BIT_VSPRINTF and CFG_64BIT_STRTOUL
735 Whithout these , LBA48 support uses 32bit variables and will 'only'
736 support disks up to 2.1TB.
739 When enabled, makes the IDE subsystem use 64bit sector addresses.
743 At the moment only there is only support for the
744 SYM53C8XX SCSI controller; define
745 CONFIG_SCSI_SYM53C8XX to enable it.
747 CFG_SCSI_MAX_LUN [8], CFG_SCSI_MAX_SCSI_ID [7] and
748 CFG_SCSI_MAX_DEVICE [CFG_SCSI_MAX_SCSI_ID *
749 CFG_SCSI_MAX_LUN] can be adjusted to define the
750 maximum numbers of LUNs, SCSI ID's and target
752 CFG_SCSI_SYM53C8XX_CCF to fix clock timing (80Mhz)
754 - NETWORK Support (PCI):
756 Support for Intel 8254x gigabit chips.
759 Support for Intel 82557/82559/82559ER chips.
760 Optional CONFIG_EEPRO100_SROM_WRITE enables eeprom
761 write routine for first time initialisation.
764 Support for Digital 2114x chips.
765 Optional CONFIG_TULIP_SELECT_MEDIA for board specific
766 modem chip initialisation (KS8761/QS6611).
769 Support for National dp83815 chips.
772 Support for National dp8382[01] gigabit chips.
774 - NETWORK Support (other):
776 CONFIG_DRIVER_LAN91C96
777 Support for SMSC's LAN91C96 chips.
780 Define this to hold the physical address
781 of the LAN91C96's I/O space
783 CONFIG_LAN91C96_USE_32_BIT
784 Define this to enable 32 bit addressing
786 CONFIG_DRIVER_SMC91111
787 Support for SMSC's LAN91C111 chip
790 Define this to hold the physical address
791 of the device (I/O space)
793 CONFIG_SMC_USE_32_BIT
794 Define this if data bus is 32 bits
796 CONFIG_SMC_USE_IOFUNCS
797 Define this to use i/o functions instead of macros
798 (some hardware wont work with macros)
801 At the moment only the UHCI host controller is
802 supported (PIP405, MIP405, MPC5200); define
803 CONFIG_USB_UHCI to enable it.
804 define CONFIG_USB_KEYBOARD to enable the USB Keyboard
805 and define CONFIG_USB_STORAGE to enable the USB
808 Supported are USB Keyboards and USB Floppy drives
810 MPC5200 USB requires additional defines:
812 for 528 MHz Clock: 0x0001bbbb
814 for differential drivers: 0x00001000
815 for single ended drivers: 0x00005000
819 The MMC controller on the Intel PXA is supported. To
820 enable this define CONFIG_MMC. The MMC can be
821 accessed from the boot prompt by mapping the device
822 to physical memory similar to flash. Command line is
823 enabled with CFG_CMD_MMC. The MMC driver also works with
824 the FAT fs. This is enabled with CFG_CMD_FAT.
826 - Journaling Flash filesystem support:
827 CONFIG_JFFS2_NAND, CONFIG_JFFS2_NAND_OFF, CONFIG_JFFS2_NAND_SIZE,
828 CONFIG_JFFS2_NAND_DEV
829 Define these for a default partition on a NAND device
831 CFG_JFFS2_FIRST_SECTOR,
832 CFG_JFFS2_FIRST_BANK, CFG_JFFS2_NUM_BANKS
833 Define these for a default partition on a NOR device
836 Define this to create an own partition. You have to provide a
837 function struct part_info* jffs2_part_info(int part_num)
839 If you define only one JFFS2 partition you may also want to
840 #define CFG_JFFS_SINGLE_PART 1
841 to disable the command chpart. This is the default when you
842 have not defined a custom partition
847 Define this to enable standard (PC-Style) keyboard
851 Standard PC keyboard driver with US (is default) and
852 GERMAN key layout (switch via environment 'keymap=de') support.
853 Export function i8042_kbd_init, i8042_tstc and i8042_getc
854 for cfb_console. Supports cursor blinking.
859 Define this to enable video support (for output to
864 Enable Chips & Technologies 69000 Video chip
866 CONFIG_VIDEO_SMI_LYNXEM
867 Enable Silicon Motion SMI 712/710/810 Video chip. The
868 video output is selected via environment 'videoout'
869 (1 = LCD and 2 = CRT). If videoout is undefined, CRT is
872 For the CT69000 and SMI_LYNXEM drivers, videomode is
873 selected via environment 'videomode'. Two diferent ways
875 - "videomode=num" 'num' is a standard LiLo mode numbers.
876 Following standard modes are supported (* is default):
878 Colors 640x480 800x600 1024x768 1152x864 1280x1024
879 -------------+---------------------------------------------
880 8 bits | 0x301* 0x303 0x305 0x161 0x307
881 15 bits | 0x310 0x313 0x316 0x162 0x319
882 16 bits | 0x311 0x314 0x317 0x163 0x31A
883 24 bits | 0x312 0x315 0x318 ? 0x31B
884 -------------+---------------------------------------------
885 (i.e. setenv videomode 317; saveenv; reset;)
887 - "videomode=bootargs" all the video parameters are parsed
888 from the bootargs. (See drivers/videomodes.c)
891 CONFIG_VIDEO_SED13806
892 Enable Epson SED13806 driver. This driver supports 8bpp
893 and 16bpp modes defined by CONFIG_VIDEO_SED13806_8BPP
894 or CONFIG_VIDEO_SED13806_16BPP
899 Define this to enable a custom keyboard support.
900 This simply calls drv_keyboard_init() which must be
901 defined in your board-specific files.
902 The only board using this so far is RBC823.
904 - LCD Support: CONFIG_LCD
906 Define this to enable LCD support (for output to LCD
907 display); also select one of the supported displays
908 by defining one of these:
910 CONFIG_NEC_NL6448AC33:
912 NEC NL6448AC33-18. Active, color, single scan.
914 CONFIG_NEC_NL6448BC20
916 NEC NL6448BC20-08. 6.5", 640x480.
917 Active, color, single scan.
919 CONFIG_NEC_NL6448BC33_54
921 NEC NL6448BC33-54. 10.4", 640x480.
922 Active, color, single scan.
926 Sharp 320x240. Active, color, single scan.
927 It isn't 16x9, and I am not sure what it is.
929 CONFIG_SHARP_LQ64D341
931 Sharp LQ64D341 display, 640x480.
932 Active, color, single scan.
936 HLD1045 display, 640x480.
937 Active, color, single scan.
941 Optrex CBL50840-2 NF-FW 99 22 M5
943 Hitachi LMG6912RPFC-00T
947 320x240. Black & white.
949 Normally display is black on white background; define
950 CFG_WHITE_ON_BLACK to get it inverted.
952 - Splash Screen Support: CONFIG_SPLASH_SCREEN
954 If this option is set, the environment is checked for
955 a variable "splashimage". If found, the usual display
956 of logo, copyright and system information on the LCD
957 is suppressed and the BMP image at the address
958 specified in "splashimage" is loaded instead. The
959 console is redirected to the "nulldev", too. This
960 allows for a "silent" boot where a splash screen is
961 loaded very quickly after power-on.
963 - Gzip compressed BMP image support: CONFIG_VIDEO_BMP_GZIP
965 If this option is set, additionally to standard BMP
966 images, gzipped BMP images can be displayed via the
967 splashscreen support or the bmp command.
969 - Compression support:
972 If this option is set, support for bzip2 compressed
973 images is included. If not, only uncompressed and gzip
974 compressed images are supported.
976 NOTE: the bzip2 algorithm requires a lot of RAM, so
977 the malloc area (as defined by CFG_MALLOC_LEN) should
983 The address of PHY on MII bus.
985 CONFIG_PHY_CLOCK_FREQ (ppc4xx)
987 The clock frequency of the MII bus
991 If this option is set, support for speed/duplex
992 detection of Gigabit PHY is included.
994 CONFIG_PHY_RESET_DELAY
996 Some PHY like Intel LXT971A need extra delay after
997 reset before any MII register access is possible.
998 For such PHY, set this option to the usec delay
999 required. (minimum 300usec for LXT971A)
1001 CONFIG_PHY_CMD_DELAY (ppc4xx)
1003 Some PHY like Intel LXT971A need extra delay after
1004 command issued before MII status register can be read
1011 Define a default value for ethernet address to use
1012 for the respective ethernet interface, in case this
1013 is not determined automatically.
1018 Define a default value for the IP address to use for
1019 the default ethernet interface, in case this is not
1020 determined through e.g. bootp.
1022 - Server IP address:
1025 Defines a default value for theIP address of a TFTP
1026 server to contact when using the "tftboot" command.
1028 - BOOTP Recovery Mode:
1029 CONFIG_BOOTP_RANDOM_DELAY
1031 If you have many targets in a network that try to
1032 boot using BOOTP, you may want to avoid that all
1033 systems send out BOOTP requests at precisely the same
1034 moment (which would happen for instance at recovery
1035 from a power failure, when all systems will try to
1036 boot, thus flooding the BOOTP server. Defining
1037 CONFIG_BOOTP_RANDOM_DELAY causes a random delay to be
1038 inserted before sending out BOOTP requests. The
1039 following delays are insterted then:
1041 1st BOOTP request: delay 0 ... 1 sec
1042 2nd BOOTP request: delay 0 ... 2 sec
1043 3rd BOOTP request: delay 0 ... 4 sec
1045 BOOTP requests: delay 0 ... 8 sec
1047 - DHCP Advanced Options:
1050 You can fine tune the DHCP functionality by adding
1051 these flags to the CONFIG_BOOTP_MASK define:
1053 CONFIG_BOOTP_DNS2 - If a DHCP client requests the DNS
1054 serverip from a DHCP server, it is possible that more
1055 than one DNS serverip is offered to the client.
1056 If CONFIG_BOOTP_DNS2 is enabled, the secondary DNS
1057 serverip will be stored in the additional environment
1058 variable "dnsip2". The first DNS serverip is always
1059 stored in the variable "dnsip", when CONFIG_BOOTP_DNS
1060 is added to the CONFIG_BOOTP_MASK.
1062 CONFIG_BOOTP_SEND_HOSTNAME - Some DHCP servers are capable
1063 to do a dynamic update of a DNS server. To do this, they
1064 need the hostname of the DHCP requester.
1065 If CONFIG_BOOP_SEND_HOSTNAME is added to the
1066 CONFIG_BOOTP_MASK, the content of the "hostname"
1067 environment variable is passed as option 12 to
1071 CONFIG_CDP_DEVICE_ID
1073 The device id used in CDP trigger frames.
1075 CONFIG_CDP_DEVICE_ID_PREFIX
1077 A two character string which is prefixed to the MAC address
1082 A printf format string which contains the ascii name of
1083 the port. Normally is set to "eth%d" which sets
1084 eth0 for the first ethernet, eth1 for the second etc.
1086 CONFIG_CDP_CAPABILITIES
1088 A 32bit integer which indicates the device capabilities;
1089 0x00000010 for a normal host which does not forwards.
1093 An ascii string containing the version of the software.
1097 An ascii string containing the name of the platform.
1101 A 32bit integer sent on the trigger.
1103 CONFIG_CDP_POWER_CONSUMPTION
1105 A 16bit integer containing the power consumption of the
1106 device in .1 of milliwatts.
1108 CONFIG_CDP_APPLIANCE_VLAN_TYPE
1110 A byte containing the id of the VLAN.
1112 - Status LED: CONFIG_STATUS_LED
1114 Several configurations allow to display the current
1115 status using a LED. For instance, the LED will blink
1116 fast while running U-Boot code, stop blinking as
1117 soon as a reply to a BOOTP request was received, and
1118 start blinking slow once the Linux kernel is running
1119 (supported by a status LED driver in the Linux
1120 kernel). Defining CONFIG_STATUS_LED enables this
1123 - CAN Support: CONFIG_CAN_DRIVER
1125 Defining CONFIG_CAN_DRIVER enables CAN driver support
1126 on those systems that support this (optional)
1127 feature, like the TQM8xxL modules.
1129 - I2C Support: CONFIG_HARD_I2C | CONFIG_SOFT_I2C
1131 These enable I2C serial bus commands. Defining either of
1132 (but not both of) CONFIG_HARD_I2C or CONFIG_SOFT_I2C will
1133 include the appropriate I2C driver for the selected cpu.
1135 This will allow you to use i2c commands at the u-boot
1136 command line (as long as you set CFG_CMD_I2C in
1137 CONFIG_COMMANDS) and communicate with i2c based realtime
1138 clock chips. See common/cmd_i2c.c for a description of the
1139 command line interface.
1141 CONFIG_HARD_I2C selects the CPM hardware driver for I2C.
1143 CONFIG_SOFT_I2C configures u-boot to use a software (aka
1144 bit-banging) driver instead of CPM or similar hardware
1147 There are several other quantities that must also be
1148 defined when you define CONFIG_HARD_I2C or CONFIG_SOFT_I2C.
1150 In both cases you will need to define CFG_I2C_SPEED
1151 to be the frequency (in Hz) at which you wish your i2c bus
1152 to run and CFG_I2C_SLAVE to be the address of this node (ie
1153 the cpu's i2c node address).
1155 Now, the u-boot i2c code for the mpc8xx (cpu/mpc8xx/i2c.c)
1156 sets the cpu up as a master node and so its address should
1157 therefore be cleared to 0 (See, eg, MPC823e User's Manual
1158 p.16-473). So, set CFG_I2C_SLAVE to 0.
1160 That's all that's required for CONFIG_HARD_I2C.
1162 If you use the software i2c interface (CONFIG_SOFT_I2C)
1163 then the following macros need to be defined (examples are
1164 from include/configs/lwmon.h):
1168 (Optional). Any commands necessary to enable the I2C
1169 controller or configure ports.
1171 eg: #define I2C_INIT (immr->im_cpm.cp_pbdir |= PB_SCL)
1175 (Only for MPC8260 CPU). The I/O port to use (the code
1176 assumes both bits are on the same port). Valid values
1177 are 0..3 for ports A..D.
1181 The code necessary to make the I2C data line active
1182 (driven). If the data line is open collector, this
1185 eg: #define I2C_ACTIVE (immr->im_cpm.cp_pbdir |= PB_SDA)
1189 The code necessary to make the I2C data line tri-stated
1190 (inactive). If the data line is open collector, this
1193 eg: #define I2C_TRISTATE (immr->im_cpm.cp_pbdir &= ~PB_SDA)
1197 Code that returns TRUE if the I2C data line is high,
1200 eg: #define I2C_READ ((immr->im_cpm.cp_pbdat & PB_SDA) != 0)
1204 If <bit> is TRUE, sets the I2C data line high. If it
1205 is FALSE, it clears it (low).
1207 eg: #define I2C_SDA(bit) \
1208 if(bit) immr->im_cpm.cp_pbdat |= PB_SDA; \
1209 else immr->im_cpm.cp_pbdat &= ~PB_SDA
1213 If <bit> is TRUE, sets the I2C clock line high. If it
1214 is FALSE, it clears it (low).
1216 eg: #define I2C_SCL(bit) \
1217 if(bit) immr->im_cpm.cp_pbdat |= PB_SCL; \
1218 else immr->im_cpm.cp_pbdat &= ~PB_SCL
1222 This delay is invoked four times per clock cycle so this
1223 controls the rate of data transfer. The data rate thus
1224 is 1 / (I2C_DELAY * 4). Often defined to be something
1227 #define I2C_DELAY udelay(2)
1231 When a board is reset during an i2c bus transfer
1232 chips might think that the current transfer is still
1233 in progress. On some boards it is possible to access
1234 the i2c SCLK line directly, either by using the
1235 processor pin as a GPIO or by having a second pin
1236 connected to the bus. If this option is defined a
1237 custom i2c_init_board() routine in boards/xxx/board.c
1238 is run early in the boot sequence.
1240 CONFIG_I2CFAST (PPC405GP|PPC405EP only)
1242 This option enables configuration of bi_iic_fast[] flags
1243 in u-boot bd_info structure based on u-boot environment
1244 variable "i2cfast". (see also i2cfast)
1246 - SPI Support: CONFIG_SPI
1248 Enables SPI driver (so far only tested with
1249 SPI EEPROM, also an instance works with Crystal A/D and
1250 D/As on the SACSng board)
1254 Enables extended (16-bit) SPI EEPROM addressing.
1255 (symmetrical to CONFIG_I2C_X)
1259 Enables a software (bit-bang) SPI driver rather than
1260 using hardware support. This is a general purpose
1261 driver that only requires three general I/O port pins
1262 (two outputs, one input) to function. If this is
1263 defined, the board configuration must define several
1264 SPI configuration items (port pins to use, etc). For
1265 an example, see include/configs/sacsng.h.
1267 - FPGA Support: CONFIG_FPGA_COUNT
1269 Specify the number of FPGA devices to support.
1273 Used to specify the types of FPGA devices. For example,
1274 #define CONFIG_FPGA CFG_XILINX_VIRTEX2
1276 CFG_FPGA_PROG_FEEDBACK
1278 Enable printing of hash marks during FPGA configuration.
1282 Enable checks on FPGA configuration interface busy
1283 status by the configuration function. This option
1284 will require a board or device specific function to
1289 If defined, a function that provides delays in the FPGA
1290 configuration driver.
1292 CFG_FPGA_CHECK_CTRLC
1293 Allow Control-C to interrupt FPGA configuration
1295 CFG_FPGA_CHECK_ERROR
1297 Check for configuration errors during FPGA bitfile
1298 loading. For example, abort during Virtex II
1299 configuration if the INIT_B line goes low (which
1300 indicated a CRC error).
1304 Maximum time to wait for the INIT_B line to deassert
1305 after PROB_B has been deasserted during a Virtex II
1306 FPGA configuration sequence. The default time is 500
1311 Maximum time to wait for BUSY to deassert during
1312 Virtex II FPGA configuration. The default is 5 mS.
1314 CFG_FPGA_WAIT_CONFIG
1316 Time to wait after FPGA configuration. The default is
1319 - Configuration Management:
1322 If defined, this string will be added to the U-Boot
1323 version information (U_BOOT_VERSION)
1325 - Vendor Parameter Protection:
1327 U-Boot considers the values of the environment
1328 variables "serial#" (Board Serial Number) and
1329 "ethaddr" (Ethernet Address) to be parameters that
1330 are set once by the board vendor / manufacturer, and
1331 protects these variables from casual modification by
1332 the user. Once set, these variables are read-only,
1333 and write or delete attempts are rejected. You can
1334 change this behviour:
1336 If CONFIG_ENV_OVERWRITE is #defined in your config
1337 file, the write protection for vendor parameters is
1338 completely disabled. Anybody can change or delete
1341 Alternatively, if you #define _both_ CONFIG_ETHADDR
1342 _and_ CONFIG_OVERWRITE_ETHADDR_ONCE, a default
1343 ethernet address is installed in the environment,
1344 which can be changed exactly ONCE by the user. [The
1345 serial# is unaffected by this, i. e. it remains
1351 Define this variable to enable the reservation of
1352 "protected RAM", i. e. RAM which is not overwritten
1353 by U-Boot. Define CONFIG_PRAM to hold the number of
1354 kB you want to reserve for pRAM. You can overwrite
1355 this default value by defining an environment
1356 variable "pram" to the number of kB you want to
1357 reserve. Note that the board info structure will
1358 still show the full amount of RAM. If pRAM is
1359 reserved, a new environment variable "mem" will
1360 automatically be defined to hold the amount of
1361 remaining RAM in a form that can be passed as boot
1362 argument to Linux, for instance like that:
1364 setenv bootargs ... mem=\$(mem)
1367 This way you can tell Linux not to use this memory,
1368 either, which results in a memory region that will
1369 not be affected by reboots.
1371 *WARNING* If your board configuration uses automatic
1372 detection of the RAM size, you must make sure that
1373 this memory test is non-destructive. So far, the
1374 following board configurations are known to be
1377 ETX094, IVMS8, IVML24, SPD8xx, TQM8xxL,
1378 HERMES, IP860, RPXlite, LWMON, LANTEC,
1379 PCU_E, FLAGADM, TQM8260
1384 Define this variable to stop the system in case of a
1385 fatal error, so that you have to reset it manually.
1386 This is probably NOT a good idea for an embedded
1387 system where you want to system to reboot
1388 automatically as fast as possible, but it may be
1389 useful during development since you can try to debug
1390 the conditions that lead to the situation.
1392 CONFIG_NET_RETRY_COUNT
1394 This variable defines the number of retries for
1395 network operations like ARP, RARP, TFTP, or BOOTP
1396 before giving up the operation. If not defined, a
1397 default value of 5 is used.
1399 - Command Interpreter:
1402 Enable auto completion of commands using TAB.
1406 Define this variable to enable the "hush" shell (from
1407 Busybox) as command line interpreter, thus enabling
1408 powerful command line syntax like
1409 if...then...else...fi conditionals or `&&' and '||'
1410 constructs ("shell scripts").
1412 If undefined, you get the old, much simpler behaviour
1413 with a somewhat smaller memory footprint.
1418 This defines the secondary prompt string, which is
1419 printed when the command interpreter needs more input
1420 to complete a command. Usually "> ".
1424 In the current implementation, the local variables
1425 space and global environment variables space are
1426 separated. Local variables are those you define by
1427 simply typing `name=value'. To access a local
1428 variable later on, you have write `$name' or
1429 `${name}'; to execute the contents of a variable
1430 directly type `$name' at the command prompt.
1432 Global environment variables are those you use
1433 setenv/printenv to work with. To run a command stored
1434 in such a variable, you need to use the run command,
1435 and you must not use the '$' sign to access them.
1437 To store commands and special characters in a
1438 variable, please use double quotation marks
1439 surrounding the whole text of the variable, instead
1440 of the backslashes before semicolons and special
1443 - Default Environment:
1444 CONFIG_EXTRA_ENV_SETTINGS
1446 Define this to contain any number of null terminated
1447 strings (variable = value pairs) that will be part of
1448 the default environment compiled into the boot image.
1450 For example, place something like this in your
1451 board's config file:
1453 #define CONFIG_EXTRA_ENV_SETTINGS \
1457 Warning: This method is based on knowledge about the
1458 internal format how the environment is stored by the
1459 U-Boot code. This is NOT an official, exported
1460 interface! Although it is unlikely that this format
1461 will change soon, there is no guarantee either.
1462 You better know what you are doing here.
1464 Note: overly (ab)use of the default environment is
1465 discouraged. Make sure to check other ways to preset
1466 the environment like the autoscript function or the
1469 - DataFlash Support:
1470 CONFIG_HAS_DATAFLASH
1472 Defining this option enables DataFlash features and
1473 allows to read/write in Dataflash via the standard
1476 - SystemACE Support:
1479 Adding this option adds support for Xilinx SystemACE
1480 chips attached via some sort of local bus. The address
1481 of the chip must alsh be defined in the
1482 CFG_SYSTEMACE_BASE macro. For example:
1484 #define CONFIG_SYSTEMACE
1485 #define CFG_SYSTEMACE_BASE 0xf0000000
1487 When SystemACE support is added, the "ace" device type
1488 becomes available to the fat commands, i.e. fatls.
1490 - Show boot progress:
1491 CONFIG_SHOW_BOOT_PROGRESS
1493 Defining this option allows to add some board-
1494 specific code (calling a user-provided function
1495 "show_boot_progress(int)") that enables you to show
1496 the system's boot progress on some display (for
1497 example, some LED's) on your board. At the moment,
1498 the following checkpoints are implemented:
1501 1 common/cmd_bootm.c before attempting to boot an image
1502 -1 common/cmd_bootm.c Image header has bad magic number
1503 2 common/cmd_bootm.c Image header has correct magic number
1504 -2 common/cmd_bootm.c Image header has bad checksum
1505 3 common/cmd_bootm.c Image header has correct checksum
1506 -3 common/cmd_bootm.c Image data has bad checksum
1507 4 common/cmd_bootm.c Image data has correct checksum
1508 -4 common/cmd_bootm.c Image is for unsupported architecture
1509 5 common/cmd_bootm.c Architecture check OK
1510 -5 common/cmd_bootm.c Wrong Image Type (not kernel, multi, standalone)
1511 6 common/cmd_bootm.c Image Type check OK
1512 -6 common/cmd_bootm.c gunzip uncompression error
1513 -7 common/cmd_bootm.c Unimplemented compression type
1514 7 common/cmd_bootm.c Uncompression OK
1515 -8 common/cmd_bootm.c Wrong Image Type (not kernel, multi, standalone)
1516 8 common/cmd_bootm.c Image Type check OK
1517 -9 common/cmd_bootm.c Unsupported OS (not Linux, BSD, VxWorks, QNX)
1518 9 common/cmd_bootm.c Start initial ramdisk verification
1519 -10 common/cmd_bootm.c Ramdisk header has bad magic number
1520 -11 common/cmd_bootm.c Ramdisk header has bad checksum
1521 10 common/cmd_bootm.c Ramdisk header is OK
1522 -12 common/cmd_bootm.c Ramdisk data has bad checksum
1523 11 common/cmd_bootm.c Ramdisk data has correct checksum
1524 12 common/cmd_bootm.c Ramdisk verification complete, start loading
1525 -13 common/cmd_bootm.c Wrong Image Type (not PPC Linux Ramdisk)
1526 13 common/cmd_bootm.c Start multifile image verification
1527 14 common/cmd_bootm.c No initial ramdisk, no multifile, continue.
1528 15 common/cmd_bootm.c All preparation done, transferring control to OS
1530 -30 lib_ppc/board.c Fatal error, hang the system
1531 -31 post/post.c POST test failed, detected by post_output_backlog()
1532 -32 post/post.c POST test failed, detected by post_run_single()
1534 -1 common/cmd_doc.c Bad usage of "doc" command
1535 -1 common/cmd_doc.c No boot device
1536 -1 common/cmd_doc.c Unknown Chip ID on boot device
1537 -1 common/cmd_doc.c Read Error on boot device
1538 -1 common/cmd_doc.c Image header has bad magic number
1540 -1 common/cmd_ide.c Bad usage of "ide" command
1541 -1 common/cmd_ide.c No boot device
1542 -1 common/cmd_ide.c Unknown boot device
1543 -1 common/cmd_ide.c Unknown partition table
1544 -1 common/cmd_ide.c Invalid partition type
1545 -1 common/cmd_ide.c Read Error on boot device
1546 -1 common/cmd_ide.c Image header has bad magic number
1548 -1 common/cmd_nand.c Bad usage of "nand" command
1549 -1 common/cmd_nand.c No boot device
1550 -1 common/cmd_nand.c Unknown Chip ID on boot device
1551 -1 common/cmd_nand.c Read Error on boot device
1552 -1 common/cmd_nand.c Image header has bad magic number
1554 -1 common/env_common.c Environment has a bad CRC, using default
1560 [so far only for SMDK2400 and TRAB boards]
1562 - Modem support endable:
1563 CONFIG_MODEM_SUPPORT
1565 - RTS/CTS Flow control enable:
1568 - Modem debug support:
1569 CONFIG_MODEM_SUPPORT_DEBUG
1571 Enables debugging stuff (char screen[1024], dbg())
1572 for modem support. Useful only with BDI2000.
1574 - Interrupt support (PPC):
1576 There are common interrupt_init() and timer_interrupt()
1577 for all PPC archs. interrupt_init() calls interrupt_init_cpu()
1578 for cpu specific initialization. interrupt_init_cpu()
1579 should set decrementer_count to appropriate value. If
1580 cpu resets decrementer automatically after interrupt
1581 (ppc4xx) it should set decrementer_count to zero.
1582 timer_interrupt() calls timer_interrupt_cpu() for cpu
1583 specific handling. If board has watchdog / status_led
1584 / other_activity_monitor it works automatically from
1585 general timer_interrupt().
1589 In the target system modem support is enabled when a
1590 specific key (key combination) is pressed during
1591 power-on. Otherwise U-Boot will boot normally
1592 (autoboot). The key_pressed() fuction is called from
1593 board_init(). Currently key_pressed() is a dummy
1594 function, returning 1 and thus enabling modem
1597 If there are no modem init strings in the
1598 environment, U-Boot proceed to autoboot; the
1599 previous output (banner, info printfs) will be
1602 See also: doc/README.Modem
1605 Configuration Settings:
1606 -----------------------
1608 - CFG_LONGHELP: Defined when you want long help messages included;
1609 undefine this when you're short of memory.
1611 - CFG_PROMPT: This is what U-Boot prints on the console to
1612 prompt for user input.
1614 - CFG_CBSIZE: Buffer size for input from the Console
1616 - CFG_PBSIZE: Buffer size for Console output
1618 - CFG_MAXARGS: max. Number of arguments accepted for monitor commands
1620 - CFG_BARGSIZE: Buffer size for Boot Arguments which are passed to
1621 the application (usually a Linux kernel) when it is
1624 - CFG_BAUDRATE_TABLE:
1625 List of legal baudrate settings for this board.
1627 - CFG_CONSOLE_INFO_QUIET
1628 Suppress display of console information at boot.
1630 - CFG_CONSOLE_IS_IN_ENV
1631 If the board specific function
1632 extern int overwrite_console (void);
1633 returns 1, the stdin, stderr and stdout are switched to the
1634 serial port, else the settings in the environment are used.
1636 - CFG_CONSOLE_OVERWRITE_ROUTINE
1637 Enable the call to overwrite_console().
1639 - CFG_CONSOLE_ENV_OVERWRITE
1640 Enable overwrite of previous console environment settings.
1642 - CFG_MEMTEST_START, CFG_MEMTEST_END:
1643 Begin and End addresses of the area used by the
1647 Enable an alternate, more extensive memory test.
1649 - CFG_MEMTEST_SCRATCH:
1650 Scratch address used by the alternate memory test
1651 You only need to set this if address zero isn't writeable
1653 - CFG_TFTP_LOADADDR:
1654 Default load address for network file downloads
1656 - CFG_LOADS_BAUD_CHANGE:
1657 Enable temporary baudrate change while serial download
1660 Physical start address of SDRAM. _Must_ be 0 here.
1663 Physical start address of Motherboard I/O (if using a
1667 Physical start address of Flash memory.
1670 Physical start address of boot monitor code (set by
1671 make config files to be same as the text base address
1672 (TEXT_BASE) used when linking) - same as
1673 CFG_FLASH_BASE when booting from flash.
1676 Size of memory reserved for monitor code, used to
1677 determine _at_compile_time_ (!) if the environment is
1678 embedded within the U-Boot image, or in a separate
1682 Size of DRAM reserved for malloc() use.
1685 Maximum size of memory mapped by the startup code of
1686 the Linux kernel; all data that must be processed by
1687 the Linux kernel (bd_info, boot arguments, eventually
1688 initrd image) must be put below this limit.
1690 - CFG_MAX_FLASH_BANKS:
1691 Max number of Flash memory banks
1693 - CFG_MAX_FLASH_SECT:
1694 Max number of sectors on a Flash chip
1696 - CFG_FLASH_ERASE_TOUT:
1697 Timeout for Flash erase operations (in ms)
1699 - CFG_FLASH_WRITE_TOUT:
1700 Timeout for Flash write operations (in ms)
1702 - CFG_FLASH_LOCK_TOUT
1703 Timeout for Flash set sector lock bit operation (in ms)
1705 - CFG_FLASH_UNLOCK_TOUT
1706 Timeout for Flash clear lock bits operation (in ms)
1708 - CFG_FLASH_PROTECTION
1709 If defined, hardware flash sectors protection is used
1710 instead of U-Boot software protection.
1712 - CFG_DIRECT_FLASH_TFTP:
1714 Enable TFTP transfers directly to flash memory;
1715 without this option such a download has to be
1716 performed in two steps: (1) download to RAM, and (2)
1717 copy from RAM to flash.
1719 The two-step approach is usually more reliable, since
1720 you can check if the download worked before you erase
1721 the flash, but in some situations (when sytem RAM is
1722 too limited to allow for a tempory copy of the
1723 downloaded image) this option may be very useful.
1726 Define if the flash driver uses extra elements in the
1727 common flash structure for storing flash geometry.
1729 - CFG_FLASH_CFI_DRIVER
1730 This option also enables the building of the cfi_flash driver
1731 in the drivers directory
1733 - CFG_RX_ETH_BUFFER:
1734 Defines the number of ethernet receive buffers. On some
1735 ethernet controllers it is recommended to set this value
1736 to 8 or even higher (EEPRO100 or 405 EMAC), since all
1737 buffers can be full shortly after enabling the interface
1738 on high ethernet traffic.
1739 Defaults to 4 if not defined.
1741 The following definitions that deal with the placement and management
1742 of environment data (variable area); in general, we support the
1743 following configurations:
1745 - CFG_ENV_IS_IN_FLASH:
1747 Define this if the environment is in flash memory.
1749 a) The environment occupies one whole flash sector, which is
1750 "embedded" in the text segment with the U-Boot code. This
1751 happens usually with "bottom boot sector" or "top boot
1752 sector" type flash chips, which have several smaller
1753 sectors at the start or the end. For instance, such a
1754 layout can have sector sizes of 8, 2x4, 16, Nx32 kB. In
1755 such a case you would place the environment in one of the
1756 4 kB sectors - with U-Boot code before and after it. With
1757 "top boot sector" type flash chips, you would put the
1758 environment in one of the last sectors, leaving a gap
1759 between U-Boot and the environment.
1763 Offset of environment data (variable area) to the
1764 beginning of flash memory; for instance, with bottom boot
1765 type flash chips the second sector can be used: the offset
1766 for this sector is given here.
1768 CFG_ENV_OFFSET is used relative to CFG_FLASH_BASE.
1772 This is just another way to specify the start address of
1773 the flash sector containing the environment (instead of
1776 - CFG_ENV_SECT_SIZE:
1778 Size of the sector containing the environment.
1781 b) Sometimes flash chips have few, equal sized, BIG sectors.
1782 In such a case you don't want to spend a whole sector for
1787 If you use this in combination with CFG_ENV_IS_IN_FLASH
1788 and CFG_ENV_SECT_SIZE, you can specify to use only a part
1789 of this flash sector for the environment. This saves
1790 memory for the RAM copy of the environment.
1792 It may also save flash memory if you decide to use this
1793 when your environment is "embedded" within U-Boot code,
1794 since then the remainder of the flash sector could be used
1795 for U-Boot code. It should be pointed out that this is
1796 STRONGLY DISCOURAGED from a robustness point of view:
1797 updating the environment in flash makes it always
1798 necessary to erase the WHOLE sector. If something goes
1799 wrong before the contents has been restored from a copy in
1800 RAM, your target system will be dead.
1802 - CFG_ENV_ADDR_REDUND
1805 These settings describe a second storage area used to hold
1806 a redundand copy of the environment data, so that there is
1807 a valid backup copy in case there is a power failure during
1808 a "saveenv" operation.
1810 BE CAREFUL! Any changes to the flash layout, and some changes to the
1811 source code will make it necessary to adapt <board>/u-boot.lds*
1815 - CFG_ENV_IS_IN_NVRAM:
1817 Define this if you have some non-volatile memory device
1818 (NVRAM, battery buffered SRAM) which you want to use for the
1824 These two #defines are used to determin the memory area you
1825 want to use for environment. It is assumed that this memory
1826 can just be read and written to, without any special
1829 BE CAREFUL! The first access to the environment happens quite early
1830 in U-Boot initalization (when we try to get the setting of for the
1831 console baudrate). You *MUST* have mappend your NVRAM area then, or
1834 Please note that even with NVRAM we still use a copy of the
1835 environment in RAM: we could work on NVRAM directly, but we want to
1836 keep settings there always unmodified except somebody uses "saveenv"
1837 to save the current settings.
1840 - CFG_ENV_IS_IN_EEPROM:
1842 Use this if you have an EEPROM or similar serial access
1843 device and a driver for it.
1848 These two #defines specify the offset and size of the
1849 environment area within the total memory of your EEPROM.
1851 - CFG_I2C_EEPROM_ADDR:
1852 If defined, specified the chip address of the EEPROM device.
1853 The default address is zero.
1855 - CFG_EEPROM_PAGE_WRITE_BITS:
1856 If defined, the number of bits used to address bytes in a
1857 single page in the EEPROM device. A 64 byte page, for example
1858 would require six bits.
1860 - CFG_EEPROM_PAGE_WRITE_DELAY_MS:
1861 If defined, the number of milliseconds to delay between
1862 page writes. The default is zero milliseconds.
1864 - CFG_I2C_EEPROM_ADDR_LEN:
1865 The length in bytes of the EEPROM memory array address. Note
1866 that this is NOT the chip address length!
1868 - CFG_I2C_EEPROM_ADDR_OVERFLOW:
1869 EEPROM chips that implement "address overflow" are ones
1870 like Catalyst 24WC04/08/16 which has 9/10/11 bits of
1871 address and the extra bits end up in the "chip address" bit
1872 slots. This makes a 24WC08 (1Kbyte) chip look like four 256
1875 Note that we consider the length of the address field to
1876 still be one byte because the extra address bits are hidden
1877 in the chip address.
1880 The size in bytes of the EEPROM device.
1883 - CFG_ENV_IS_IN_DATAFLASH:
1885 Define this if you have a DataFlash memory device which you
1886 want to use for the environment.
1892 These three #defines specify the offset and size of the
1893 environment area within the total memory of your DataFlash placed
1894 at the specified address.
1896 - CFG_ENV_IS_IN_NAND:
1898 Define this if you have a NAND device which you want to use
1899 for the environment.
1904 These two #defines specify the offset and size of the environment
1905 area within the first NAND device.
1907 - CFG_SPI_INIT_OFFSET
1909 Defines offset to the initial SPI buffer area in DPRAM. The
1910 area is used at an early stage (ROM part) if the environment
1911 is configured to reside in the SPI EEPROM: We need a 520 byte
1912 scratch DPRAM area. It is used between the two initialization
1913 calls (spi_init_f() and spi_init_r()). A value of 0xB00 seems
1914 to be a good choice since it makes it far enough from the
1915 start of the data area as well as from the stack pointer.
1917 Please note that the environment is read-only as long as the monitor
1918 has been relocated to RAM and a RAM copy of the environment has been
1919 created; also, when using EEPROM you will have to use getenv_r()
1920 until then to read environment variables.
1922 The environment is protected by a CRC32 checksum. Before the monitor
1923 is relocated into RAM, as a result of a bad CRC you will be working
1924 with the compiled-in default environment - *silently*!!! [This is
1925 necessary, because the first environment variable we need is the
1926 "baudrate" setting for the console - if we have a bad CRC, we don't
1927 have any device yet where we could complain.]
1929 Note: once the monitor has been relocated, then it will complain if
1930 the default environment is used; a new CRC is computed as soon as you
1931 use the "saveenv" command to store a valid environment.
1933 - CFG_FAULT_ECHO_LINK_DOWN:
1934 Echo the inverted Ethernet link state to the fault LED.
1936 Note: If this option is active, then CFG_FAULT_MII_ADDR
1937 also needs to be defined.
1939 - CFG_FAULT_MII_ADDR:
1940 MII address of the PHY to check for the Ethernet link state.
1942 - CFG_64BIT_VSPRINTF:
1943 Makes vsprintf (and all *printf functions) support printing
1944 of 64bit values by using the L quantifier
1946 - CFG_64BIT_STRTOUL:
1947 Adds simple_strtoull that returns a 64bit value
1949 Low Level (hardware related) configuration options:
1950 ---------------------------------------------------
1952 - CFG_CACHELINE_SIZE:
1953 Cache Line Size of the CPU.
1956 Default address of the IMMR after system reset.
1958 Needed on some 8260 systems (MPC8260ADS, PQ2FADS-ZU,
1959 and RPXsuper) to be able to adjust the position of
1960 the IMMR register after a reset.
1962 - Floppy Disk Support:
1963 CFG_FDC_DRIVE_NUMBER
1965 the default drive number (default value 0)
1969 defines the spacing between fdc chipset registers
1974 defines the offset of register from address. It
1975 depends on which part of the data bus is connected to
1976 the fdc chipset. (default value 0)
1978 If CFG_ISA_IO_STRIDE CFG_ISA_IO_OFFSET and
1979 CFG_FDC_DRIVE_NUMBER are undefined, they take their
1982 if CFG_FDC_HW_INIT is defined, then the function
1983 fdc_hw_init() is called at the beginning of the FDC
1984 setup. fdc_hw_init() must be provided by the board
1985 source code. It is used to make hardware dependant
1988 - CFG_IMMR: Physical address of the Internal Memory.
1989 DO NOT CHANGE unless you know exactly what you're
1990 doing! (11-4) [MPC8xx/82xx systems only]
1992 - CFG_INIT_RAM_ADDR:
1994 Start address of memory area that can be used for
1995 initial data and stack; please note that this must be
1996 writable memory that is working WITHOUT special
1997 initialization, i. e. you CANNOT use normal RAM which
1998 will become available only after programming the
1999 memory controller and running certain initialization
2002 U-Boot uses the following memory types:
2003 - MPC8xx and MPC8260: IMMR (internal memory of the CPU)
2004 - MPC824X: data cache
2005 - PPC4xx: data cache
2007 - CFG_GBL_DATA_OFFSET:
2009 Offset of the initial data structure in the memory
2010 area defined by CFG_INIT_RAM_ADDR. Usually
2011 CFG_GBL_DATA_OFFSET is chosen such that the initial
2012 data is located at the end of the available space
2013 (sometimes written as (CFG_INIT_RAM_END -
2014 CFG_INIT_DATA_SIZE), and the initial stack is just
2015 below that area (growing from (CFG_INIT_RAM_ADDR +
2016 CFG_GBL_DATA_OFFSET) downward.
2019 On the MPC824X (or other systems that use the data
2020 cache for initial memory) the address chosen for
2021 CFG_INIT_RAM_ADDR is basically arbitrary - it must
2022 point to an otherwise UNUSED address space between
2023 the top of RAM and the start of the PCI space.
2025 - CFG_SIUMCR: SIU Module Configuration (11-6)
2027 - CFG_SYPCR: System Protection Control (11-9)
2029 - CFG_TBSCR: Time Base Status and Control (11-26)
2031 - CFG_PISCR: Periodic Interrupt Status and Control (11-31)
2033 - CFG_PLPRCR: PLL, Low-Power, and Reset Control Register (15-30)
2035 - CFG_SCCR: System Clock and reset Control Register (15-27)
2037 - CFG_OR_TIMING_SDRAM:
2041 periodic timer for refresh
2043 - CFG_DER: Debug Event Register (37-47)
2045 - FLASH_BASE0_PRELIM, FLASH_BASE1_PRELIM, CFG_REMAP_OR_AM,
2046 CFG_PRELIM_OR_AM, CFG_OR_TIMING_FLASH, CFG_OR0_REMAP,
2047 CFG_OR0_PRELIM, CFG_BR0_PRELIM, CFG_OR1_REMAP, CFG_OR1_PRELIM,
2049 Memory Controller Definitions: BR0/1 and OR0/1 (FLASH)
2051 - SDRAM_BASE2_PRELIM, SDRAM_BASE3_PRELIM, SDRAM_MAX_SIZE,
2052 CFG_OR_TIMING_SDRAM, CFG_OR2_PRELIM, CFG_BR2_PRELIM,
2053 CFG_OR3_PRELIM, CFG_BR3_PRELIM:
2054 Memory Controller Definitions: BR2/3 and OR2/3 (SDRAM)
2056 - CFG_MAMR_PTA, CFG_MPTPR_2BK_4K, CFG_MPTPR_1BK_4K, CFG_MPTPR_2BK_8K,
2057 CFG_MPTPR_1BK_8K, CFG_MAMR_8COL, CFG_MAMR_9COL:
2058 Machine Mode Register and Memory Periodic Timer
2059 Prescaler definitions (SDRAM timing)
2061 - CFG_I2C_UCODE_PATCH, CFG_I2C_DPMEM_OFFSET [0x1FC0]:
2062 enable I2C microcode relocation patch (MPC8xx);
2063 define relocation offset in DPRAM [DSP2]
2065 - CFG_SPI_UCODE_PATCH, CFG_SPI_DPMEM_OFFSET [0x1FC0]:
2066 enable SPI microcode relocation patch (MPC8xx);
2067 define relocation offset in DPRAM [SCC4]
2070 Use OSCM clock mode on MBX8xx board. Be careful,
2071 wrong setting might damage your board. Read
2072 doc/README.MBX before setting this variable!
2074 - CFG_CPM_POST_WORD_ADDR: (MPC8xx, MPC8260 only)
2075 Offset of the bootmode word in DPRAM used by post
2076 (Power On Self Tests). This definition overrides
2077 #define'd default value in commproc.h resp.
2080 - CFG_PCI_SLV_MEM_LOCAL, CFG_PCI_SLV_MEM_BUS, CFG_PICMR0_MASK_ATTRIB,
2081 CFG_PCI_MSTR0_LOCAL, CFG_PCIMSK0_MASK, CFG_PCI_MSTR1_LOCAL,
2082 CFG_PCIMSK1_MASK, CFG_PCI_MSTR_MEM_LOCAL, CFG_PCI_MSTR_MEM_BUS,
2083 CFG_CPU_PCI_MEM_START, CFG_PCI_MSTR_MEM_SIZE, CFG_POCMR0_MASK_ATTRIB,
2084 CFG_PCI_MSTR_MEMIO_LOCAL, CFG_PCI_MSTR_MEMIO_BUS, CPU_PCI_MEMIO_START,
2085 CFG_PCI_MSTR_MEMIO_SIZE, CFG_POCMR1_MASK_ATTRIB, CFG_PCI_MSTR_IO_LOCAL,
2086 CFG_PCI_MSTR_IO_BUS, CFG_CPU_PCI_IO_START, CFG_PCI_MSTR_IO_SIZE,
2087 CFG_POCMR2_MASK_ATTRIB: (MPC826x only)
2088 Overrides the default PCI memory map in cpu/mpc8260/pci.c if set.
2090 - CONFIG_ETHER_ON_FEC[12]
2091 Define to enable FEC[12] on a 8xx series processor.
2093 - CONFIG_FEC[12]_PHY
2094 Define to the hardcoded PHY address which corresponds
2095 to the given FEC; i. e.
2096 #define CONFIG_FEC1_PHY 4
2097 means that the PHY with address 4 is connected to FEC1
2099 When set to -1, means to probe for first available.
2101 - CONFIG_FEC[12]_PHY_NORXERR
2102 The PHY does not have a RXERR line (RMII only).
2103 (so program the FEC to ignore it).
2106 Enable RMII mode for all FECs.
2107 Note that this is a global option, we can't
2108 have one FEC in standard MII mode and another in RMII mode.
2110 - CONFIG_CRC32_VERIFY
2111 Add a verify option to the crc32 command.
2114 => crc32 -v <address> <count> <crc32>
2116 Where address/count indicate a memory area
2117 and crc32 is the correct crc32 which the
2121 Add the "loopw" memory command. This only takes effect if
2122 the memory commands are activated globally (CFG_CMD_MEM).
2125 Add the "mdc" and "mwc" memory commands. These are cyclic
2130 This command will print 4 bytes (10,11,12,13) each 500 ms.
2132 => mwc.l 100 12345678 10
2133 This command will write 12345678 to address 100 all 10 ms.
2135 This only takes effect if the memory commands are activated
2136 globally (CFG_CMD_MEM).
2138 - CONFIG_SKIP_LOWLEVEL_INIT
2139 - CONFIG_SKIP_RELOCATE_UBOOT
2141 [ARM only] If these variables are defined, then
2142 certain low level initializations (like setting up
2143 the memory controller) are omitted and/or U-Boot does
2144 not relocate itself into RAM.
2145 Normally these variables MUST NOT be defined. The
2146 only exception is when U-Boot is loaded (to RAM) by
2147 some other boot loader or by a debugger which
2148 performs these intializations itself.
2151 Building the Software:
2152 ======================
2154 Building U-Boot has been tested in native PPC environments (on a
2155 PowerBook G3 running LinuxPPC 2000) and in cross environments
2156 (running RedHat 6.x and 7.x Linux on x86, Solaris 2.6 on a SPARC, and
2159 If you are not using a native PPC environment, it is assumed that you
2160 have the GNU cross compiling tools available in your path and named
2161 with a prefix of "powerpc-linux-". If this is not the case, (e.g. if
2162 you are using Monta Vista's Hard Hat Linux CDK 1.2) you must change
2163 the definition of CROSS_COMPILE in Makefile. For HHL on a 4xx CPU,
2166 CROSS_COMPILE = ppc_4xx-
2169 U-Boot is intended to be simple to build. After installing the
2170 sources you must configure U-Boot for one specific board type. This
2175 where "NAME_config" is the name of one of the existing
2176 configurations; the following names are supported:
2178 ADCIOP_config FPS860L_config omap730p2_config
2179 ADS860_config GEN860T_config pcu_e_config
2181 AR405_config GENIETV_config PIP405_config
2182 at91rm9200dk_config GTH_config QS823_config
2183 CANBT_config hermes_config QS850_config
2184 cmi_mpc5xx_config hymod_config QS860T_config
2185 cogent_common_config IP860_config RPXlite_config
2186 cogent_mpc8260_config IVML24_config RPXlite_DW_config
2187 cogent_mpc8xx_config IVMS8_config RPXsuper_config
2188 CPCI405_config JSE_config rsdproto_config
2189 CPCIISER4_config LANTEC_config Sandpoint8240_config
2190 csb272_config lwmon_config sbc8260_config
2191 CU824_config MBX860T_config sbc8560_33_config
2192 DUET_ADS_config MBX_config sbc8560_66_config
2193 EBONY_config MPC8260ADS_config SM850_config
2194 ELPT860_config MPC8540ADS_config SPD823TS_config
2195 ESTEEM192E_config MPC8540EVAL_config stxgp3_config
2196 ETX094_config MPC8560ADS_config SXNI855T_config
2197 FADS823_config NETVIA_config TQM823L_config
2198 FADS850SAR_config omap1510inn_config TQM850L_config
2199 FADS860T_config omap1610h2_config TQM855L_config
2200 FPS850L_config omap1610inn_config TQM860L_config
2201 omap5912osk_config walnut_config
2202 omap2420h4_config Yukon8220_config
2205 Note: for some board special configuration names may exist; check if
2206 additional information is available from the board vendor; for
2207 instance, the TQM823L systems are available without (standard)
2208 or with LCD support. You can select such additional "features"
2209 when chosing the configuration, i. e.
2212 - will configure for a plain TQM823L, i. e. no LCD support
2214 make TQM823L_LCD_config
2215 - will configure for a TQM823L with U-Boot console on LCD
2220 Finally, type "make all", and you should get some working U-Boot
2221 images ready for download to / installation on your system:
2223 - "u-boot.bin" is a raw binary image
2224 - "u-boot" is an image in ELF binary format
2225 - "u-boot.srec" is in Motorola S-Record format
2228 Please be aware that the Makefiles assume you are using GNU make, so
2229 for instance on NetBSD you might need to use "gmake" instead of
2233 If the system board that you have is not listed, then you will need
2234 to port U-Boot to your hardware platform. To do this, follow these
2237 1. Add a new configuration option for your board to the toplevel
2238 "Makefile" and to the "MAKEALL" script, using the existing
2239 entries as examples. Note that here and at many other places
2240 boards and other names are listed in alphabetical sort order. Please
2242 2. Create a new directory to hold your board specific code. Add any
2243 files you need. In your board directory, you will need at least
2244 the "Makefile", a "<board>.c", "flash.c" and "u-boot.lds".
2245 3. Create a new configuration file "include/configs/<board>.h" for
2247 3. If you're porting U-Boot to a new CPU, then also create a new
2248 directory to hold your CPU specific code. Add any files you need.
2249 4. Run "make <board>_config" with your new name.
2250 5. Type "make", and you should get a working "u-boot.srec" file
2251 to be installed on your target system.
2252 6. Debug and solve any problems that might arise.
2253 [Of course, this last step is much harder than it sounds.]
2256 Testing of U-Boot Modifications, Ports to New Hardware, etc.:
2257 ==============================================================
2259 If you have modified U-Boot sources (for instance added a new board
2260 or support for new devices, a new CPU, etc.) you are expected to
2261 provide feedback to the other developers. The feedback normally takes
2262 the form of a "patch", i. e. a context diff against a certain (latest
2263 official or latest in CVS) version of U-Boot sources.
2265 But before you submit such a patch, please verify that your modifi-
2266 cation did not break existing code. At least make sure that *ALL* of
2267 the supported boards compile WITHOUT ANY compiler warnings. To do so,
2268 just run the "MAKEALL" script, which will configure and build U-Boot
2269 for ALL supported system. Be warned, this will take a while. You can
2270 select which (cross) compiler to use by passing a `CROSS_COMPILE'
2271 environment variable to the script, i. e. to use the cross tools from
2272 MontaVista's Hard Hat Linux you can type
2274 CROSS_COMPILE=ppc_8xx- MAKEALL
2276 or to build on a native PowerPC system you can type
2278 CROSS_COMPILE=' ' MAKEALL
2280 See also "U-Boot Porting Guide" below.
2283 Monitor Commands - Overview:
2284 ============================
2286 go - start application at address 'addr'
2287 run - run commands in an environment variable
2288 bootm - boot application image from memory
2289 bootp - boot image via network using BootP/TFTP protocol
2290 tftpboot- boot image via network using TFTP protocol
2291 and env variables "ipaddr" and "serverip"
2292 (and eventually "gatewayip")
2293 rarpboot- boot image via network using RARP/TFTP protocol
2294 diskboot- boot from IDE devicebootd - boot default, i.e., run 'bootcmd'
2295 loads - load S-Record file over serial line
2296 loadb - load binary file over serial line (kermit mode)
2298 mm - memory modify (auto-incrementing)
2299 nm - memory modify (constant address)
2300 mw - memory write (fill)
2302 cmp - memory compare
2303 crc32 - checksum calculation
2304 imd - i2c memory display
2305 imm - i2c memory modify (auto-incrementing)
2306 inm - i2c memory modify (constant address)
2307 imw - i2c memory write (fill)
2308 icrc32 - i2c checksum calculation
2309 iprobe - probe to discover valid I2C chip addresses
2310 iloop - infinite loop on address range
2311 isdram - print SDRAM configuration information
2312 sspi - SPI utility commands
2313 base - print or set address offset
2314 printenv- print environment variables
2315 setenv - set environment variables
2316 saveenv - save environment variables to persistent storage
2317 protect - enable or disable FLASH write protection
2318 erase - erase FLASH memory
2319 flinfo - print FLASH memory information
2320 bdinfo - print Board Info structure
2321 iminfo - print header information for application image
2322 coninfo - print console devices and informations
2323 ide - IDE sub-system
2324 loop - infinite loop on address range
2325 loopw - infinite write loop on address range
2326 mtest - simple RAM test
2327 icache - enable or disable instruction cache
2328 dcache - enable or disable data cache
2329 reset - Perform RESET of the CPU
2330 echo - echo args to console
2331 version - print monitor version
2332 help - print online help
2333 ? - alias for 'help'
2336 Monitor Commands - Detailed Description:
2337 ========================================
2341 For now: just type "help <command>".
2344 Environment Variables:
2345 ======================
2347 U-Boot supports user configuration using Environment Variables which
2348 can be made persistent by saving to Flash memory.
2350 Environment Variables are set using "setenv", printed using
2351 "printenv", and saved to Flash using "saveenv". Using "setenv"
2352 without a value can be used to delete a variable from the
2353 environment. As long as you don't save the environment you are
2354 working with an in-memory copy. In case the Flash area containing the
2355 environment is erased by accident, a default environment is provided.
2357 Some configuration options can be set using Environment Variables:
2359 baudrate - see CONFIG_BAUDRATE
2361 bootdelay - see CONFIG_BOOTDELAY
2363 bootcmd - see CONFIG_BOOTCOMMAND
2365 bootargs - Boot arguments when booting an RTOS image
2367 bootfile - Name of the image to load with TFTP
2369 autoload - if set to "no" (any string beginning with 'n'),
2370 "bootp" will just load perform a lookup of the
2371 configuration from the BOOTP server, but not try to
2372 load any image using TFTP
2374 autostart - if set to "yes", an image loaded using the "bootp",
2375 "rarpboot", "tftpboot" or "diskboot" commands will
2376 be automatically started (by internally calling
2379 If set to "no", a standalone image passed to the
2380 "bootm" command will be copied to the load address
2381 (and eventually uncompressed), but NOT be started.
2382 This can be used to load and uncompress arbitrary
2385 i2cfast - (PPC405GP|PPC405EP only)
2386 if set to 'y' configures Linux I2C driver for fast
2387 mode (400kHZ). This environment variable is used in
2388 initialization code. So, for changes to be effective
2389 it must be saved and board must be reset.
2391 initrd_high - restrict positioning of initrd images:
2392 If this variable is not set, initrd images will be
2393 copied to the highest possible address in RAM; this
2394 is usually what you want since it allows for
2395 maximum initrd size. If for some reason you want to
2396 make sure that the initrd image is loaded below the
2397 CFG_BOOTMAPSZ limit, you can set this environment
2398 variable to a value of "no" or "off" or "0".
2399 Alternatively, you can set it to a maximum upper
2400 address to use (U-Boot will still check that it
2401 does not overwrite the U-Boot stack and data).
2403 For instance, when you have a system with 16 MB
2404 RAM, and want to reserve 4 MB from use by Linux,
2405 you can do this by adding "mem=12M" to the value of
2406 the "bootargs" variable. However, now you must make
2407 sure that the initrd image is placed in the first
2408 12 MB as well - this can be done with
2410 setenv initrd_high 00c00000
2412 If you set initrd_high to 0xFFFFFFFF, this is an
2413 indication to U-Boot that all addresses are legal
2414 for the Linux kernel, including addresses in flash
2415 memory. In this case U-Boot will NOT COPY the
2416 ramdisk at all. This may be useful to reduce the
2417 boot time on your system, but requires that this
2418 feature is supported by your Linux kernel.
2420 ipaddr - IP address; needed for tftpboot command
2422 loadaddr - Default load address for commands like "bootp",
2423 "rarpboot", "tftpboot", "loadb" or "diskboot"
2425 loads_echo - see CONFIG_LOADS_ECHO
2427 serverip - TFTP server IP address; needed for tftpboot command
2429 bootretry - see CONFIG_BOOT_RETRY_TIME
2431 bootdelaykey - see CONFIG_AUTOBOOT_DELAY_STR
2433 bootstopkey - see CONFIG_AUTOBOOT_STOP_STR
2435 ethprime - When CONFIG_NET_MULTI is enabled controls which
2436 interface is used first.
2438 ethact - When CONFIG_NET_MULTI is enabled controls which
2439 interface is currently active. For example you
2440 can do the following
2442 => setenv ethact FEC ETHERNET
2443 => ping 192.168.0.1 # traffic sent on FEC ETHERNET
2444 => setenv ethact SCC ETHERNET
2445 => ping 10.0.0.1 # traffic sent on SCC ETHERNET
2447 netretry - When set to "no" each network operation will
2448 either succeed or fail without retrying.
2449 When set to "once" the network operation will
2450 fail when all the available network interfaces
2451 are tried once without success.
2452 Useful on scripts which control the retry operation
2455 vlan - When set to a value < 4095 the traffic over
2456 ethernet is encapsulated/received over 802.1q
2459 The following environment variables may be used and automatically
2460 updated by the network boot commands ("bootp" and "rarpboot"),
2461 depending the information provided by your boot server:
2463 bootfile - see above
2464 dnsip - IP address of your Domain Name Server
2465 dnsip2 - IP address of your secondary Domain Name Server
2466 gatewayip - IP address of the Gateway (Router) to use
2467 hostname - Target hostname
2469 netmask - Subnet Mask
2470 rootpath - Pathname of the root filesystem on the NFS server
2471 serverip - see above
2474 There are two special Environment Variables:
2476 serial# - contains hardware identification information such
2477 as type string and/or serial number
2478 ethaddr - Ethernet address
2480 These variables can be set only once (usually during manufacturing of
2481 the board). U-Boot refuses to delete or overwrite these variables
2482 once they have been set once.
2485 Further special Environment Variables:
2487 ver - Contains the U-Boot version string as printed
2488 with the "version" command. This variable is
2489 readonly (see CONFIG_VERSION_VARIABLE).
2492 Please note that changes to some configuration parameters may take
2493 only effect after the next boot (yes, that's just like Windoze :-).
2496 Command Line Parsing:
2497 =====================
2499 There are two different command line parsers available with U-Boot:
2500 the old "simple" one, and the much more powerful "hush" shell:
2502 Old, simple command line parser:
2503 --------------------------------
2505 - supports environment variables (through setenv / saveenv commands)
2506 - several commands on one line, separated by ';'
2507 - variable substitution using "... $(name) ..." syntax
2508 - special characters ('$', ';') can be escaped by prefixing with '\',
2510 setenv bootcmd bootm \$(address)
2511 - You can also escape text by enclosing in single apostrophes, for example:
2512 setenv addip 'setenv bootargs $bootargs ip=$ipaddr:$serverip:$gatewayip:$netmask:$hostname::off'
2517 - similar to Bourne shell, with control structures like
2518 if...then...else...fi, for...do...done; while...do...done,
2519 until...do...done, ...
2520 - supports environment ("global") variables (through setenv / saveenv
2521 commands) and local shell variables (through standard shell syntax
2522 "name=value"); only environment variables can be used with "run"
2528 (1) If a command line (or an environment variable executed by a "run"
2529 command) contains several commands separated by semicolon, and
2530 one of these commands fails, then the remaining commands will be
2533 (2) If you execute several variables with one call to run (i. e.
2534 calling run with a list af variables as arguments), any failing
2535 command will cause "run" to terminate, i. e. the remaining
2536 variables are not executed.
2538 Note for Redundant Ethernet Interfaces:
2539 =======================================
2541 Some boards come with redundant ethernet interfaces; U-Boot supports
2542 such configurations and is capable of automatic selection of a
2543 "working" interface when needed. MAC assignment works as follows:
2545 Network interfaces are numbered eth0, eth1, eth2, ... Corresponding
2546 MAC addresses can be stored in the environment as "ethaddr" (=>eth0),
2547 "eth1addr" (=>eth1), "eth2addr", ...
2549 If the network interface stores some valid MAC address (for instance
2550 in SROM), this is used as default address if there is NO correspon-
2551 ding setting in the environment; if the corresponding environment
2552 variable is set, this overrides the settings in the card; that means:
2554 o If the SROM has a valid MAC address, and there is no address in the
2555 environment, the SROM's address is used.
2557 o If there is no valid address in the SROM, and a definition in the
2558 environment exists, then the value from the environment variable is
2561 o If both the SROM and the environment contain a MAC address, and
2562 both addresses are the same, this MAC address is used.
2564 o If both the SROM and the environment contain a MAC address, and the
2565 addresses differ, the value from the environment is used and a
2568 o If neither SROM nor the environment contain a MAC address, an error
2575 The "boot" commands of this monitor operate on "image" files which
2576 can be basicly anything, preceeded by a special header; see the
2577 definitions in include/image.h for details; basicly, the header
2578 defines the following image properties:
2580 * Target Operating System (Provisions for OpenBSD, NetBSD, FreeBSD,
2581 4.4BSD, Linux, SVR4, Esix, Solaris, Irix, SCO, Dell, NCR, VxWorks,
2582 LynxOS, pSOS, QNX, RTEMS, ARTOS;
2583 Currently supported: Linux, NetBSD, VxWorks, QNX, RTEMS, ARTOS, LynxOS).
2584 * Target CPU Architecture (Provisions for Alpha, ARM, Intel x86,
2585 IA64, MIPS, NIOS, PowerPC, IBM S390, SuperH, Sparc, Sparc 64 Bit;
2586 Currently supported: ARM, Intel x86, MIPS, NIOS, PowerPC).
2587 * Compression Type (uncompressed, gzip, bzip2)
2593 The header is marked by a special Magic Number, and both the header
2594 and the data portions of the image are secured against corruption by
2601 Although U-Boot should support any OS or standalone application
2602 easily, the main focus has always been on Linux during the design of
2605 U-Boot includes many features that so far have been part of some
2606 special "boot loader" code within the Linux kernel. Also, any
2607 "initrd" images to be used are no longer part of one big Linux image;
2608 instead, kernel and "initrd" are separate images. This implementation
2609 serves several purposes:
2611 - the same features can be used for other OS or standalone
2612 applications (for instance: using compressed images to reduce the
2613 Flash memory footprint)
2615 - it becomes much easier to port new Linux kernel versions because
2616 lots of low-level, hardware dependent stuff are done by U-Boot
2618 - the same Linux kernel image can now be used with different "initrd"
2619 images; of course this also means that different kernel images can
2620 be run with the same "initrd". This makes testing easier (you don't
2621 have to build a new "zImage.initrd" Linux image when you just
2622 change a file in your "initrd"). Also, a field-upgrade of the
2623 software is easier now.
2629 Porting Linux to U-Boot based systems:
2630 ---------------------------------------
2632 U-Boot cannot save you from doing all the necessary modifications to
2633 configure the Linux device drivers for use with your target hardware
2634 (no, we don't intend to provide a full virtual machine interface to
2637 But now you can ignore ALL boot loader code (in arch/ppc/mbxboot).
2639 Just make sure your machine specific header file (for instance
2640 include/asm-ppc/tqm8xx.h) includes the same definition of the Board
2641 Information structure as we define in include/u-boot.h, and make
2642 sure that your definition of IMAP_ADDR uses the same value as your
2643 U-Boot configuration in CFG_IMMR.
2646 Configuring the Linux kernel:
2647 -----------------------------
2649 No specific requirements for U-Boot. Make sure you have some root
2650 device (initial ramdisk, NFS) for your target system.
2653 Building a Linux Image:
2654 -----------------------
2656 With U-Boot, "normal" build targets like "zImage" or "bzImage" are
2657 not used. If you use recent kernel source, a new build target
2658 "uImage" will exist which automatically builds an image usable by
2659 U-Boot. Most older kernels also have support for a "pImage" target,
2660 which was introduced for our predecessor project PPCBoot and uses a
2661 100% compatible format.
2670 The "uImage" build target uses a special tool (in 'tools/mkimage') to
2671 encapsulate a compressed Linux kernel image with header information,
2672 CRC32 checksum etc. for use with U-Boot. This is what we are doing:
2674 * build a standard "vmlinux" kernel image (in ELF binary format):
2676 * convert the kernel into a raw binary image:
2678 ${CROSS_COMPILE}-objcopy -O binary \
2679 -R .note -R .comment \
2680 -S vmlinux linux.bin
2682 * compress the binary image:
2686 * package compressed binary image for U-Boot:
2688 mkimage -A ppc -O linux -T kernel -C gzip \
2689 -a 0 -e 0 -n "Linux Kernel Image" \
2690 -d linux.bin.gz uImage
2693 The "mkimage" tool can also be used to create ramdisk images for use
2694 with U-Boot, either separated from the Linux kernel image, or
2695 combined into one file. "mkimage" encapsulates the images with a 64
2696 byte header containing information about target architecture,
2697 operating system, image type, compression method, entry points, time
2698 stamp, CRC32 checksums, etc.
2700 "mkimage" can be called in two ways: to verify existing images and
2701 print the header information, or to build new images.
2703 In the first form (with "-l" option) mkimage lists the information
2704 contained in the header of an existing U-Boot image; this includes
2705 checksum verification:
2707 tools/mkimage -l image
2708 -l ==> list image header information
2710 The second form (with "-d" option) is used to build a U-Boot image
2711 from a "data file" which is used as image payload:
2713 tools/mkimage -A arch -O os -T type -C comp -a addr -e ep \
2714 -n name -d data_file image
2715 -A ==> set architecture to 'arch'
2716 -O ==> set operating system to 'os'
2717 -T ==> set image type to 'type'
2718 -C ==> set compression type 'comp'
2719 -a ==> set load address to 'addr' (hex)
2720 -e ==> set entry point to 'ep' (hex)
2721 -n ==> set image name to 'name'
2722 -d ==> use image data from 'datafile'
2724 Right now, all Linux kernels for PowerPC systems use the same load
2725 address (0x00000000), but the entry point address depends on the
2728 - 2.2.x kernels have the entry point at 0x0000000C,
2729 - 2.3.x and later kernels have the entry point at 0x00000000.
2731 So a typical call to build a U-Boot image would read:
2733 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \
2734 > -A ppc -O linux -T kernel -C gzip -a 0 -e 0 \
2735 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/ppc/coffboot/vmlinux.gz \
2736 > examples/uImage.TQM850L
2737 Image Name: 2.4.4 kernel for TQM850L
2738 Created: Wed Jul 19 02:34:59 2000
2739 Image Type: PowerPC Linux Kernel Image (gzip compressed)
2740 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB
2741 Load Address: 0x00000000
2742 Entry Point: 0x00000000
2744 To verify the contents of the image (or check for corruption):
2746 -> tools/mkimage -l examples/uImage.TQM850L
2747 Image Name: 2.4.4 kernel for TQM850L
2748 Created: Wed Jul 19 02:34:59 2000
2749 Image Type: PowerPC Linux Kernel Image (gzip compressed)
2750 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB
2751 Load Address: 0x00000000
2752 Entry Point: 0x00000000
2754 NOTE: for embedded systems where boot time is critical you can trade
2755 speed for memory and install an UNCOMPRESSED image instead: this
2756 needs more space in Flash, but boots much faster since it does not
2757 need to be uncompressed:
2759 -> gunzip /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/ppc/coffboot/vmlinux.gz
2760 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \
2761 > -A ppc -O linux -T kernel -C none -a 0 -e 0 \
2762 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/ppc/coffboot/vmlinux \
2763 > examples/uImage.TQM850L-uncompressed
2764 Image Name: 2.4.4 kernel for TQM850L
2765 Created: Wed Jul 19 02:34:59 2000
2766 Image Type: PowerPC Linux Kernel Image (uncompressed)
2767 Data Size: 792160 Bytes = 773.59 kB = 0.76 MB
2768 Load Address: 0x00000000
2769 Entry Point: 0x00000000
2772 Similar you can build U-Boot images from a 'ramdisk.image.gz' file
2773 when your kernel is intended to use an initial ramdisk:
2775 -> tools/mkimage -n 'Simple Ramdisk Image' \
2776 > -A ppc -O linux -T ramdisk -C gzip \
2777 > -d /LinuxPPC/images/SIMPLE-ramdisk.image.gz examples/simple-initrd
2778 Image Name: Simple Ramdisk Image
2779 Created: Wed Jan 12 14:01:50 2000
2780 Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
2781 Data Size: 566530 Bytes = 553.25 kB = 0.54 MB
2782 Load Address: 0x00000000
2783 Entry Point: 0x00000000
2786 Installing a Linux Image:
2787 -------------------------
2789 To downloading a U-Boot image over the serial (console) interface,
2790 you must convert the image to S-Record format:
2792 objcopy -I binary -O srec examples/image examples/image.srec
2794 The 'objcopy' does not understand the information in the U-Boot
2795 image header, so the resulting S-Record file will be relative to
2796 address 0x00000000. To load it to a given address, you need to
2797 specify the target address as 'offset' parameter with the 'loads'
2800 Example: install the image to address 0x40100000 (which on the
2801 TQM8xxL is in the first Flash bank):
2803 => erase 40100000 401FFFFF
2809 ## Ready for S-Record download ...
2810 ~>examples/image.srec
2811 1 2 3 4 5 6 7 8 9 10 11 12 13 ...
2813 15989 15990 15991 15992
2814 [file transfer complete]
2816 ## Start Addr = 0x00000000
2819 You can check the success of the download using the 'iminfo' command;
2820 this includes a checksum verification so you can be sure no data
2821 corruption happened:
2825 ## Checking Image at 40100000 ...
2826 Image Name: 2.2.13 for initrd on TQM850L
2827 Image Type: PowerPC Linux Kernel Image (gzip compressed)
2828 Data Size: 335725 Bytes = 327 kB = 0 MB
2829 Load Address: 00000000
2830 Entry Point: 0000000c
2831 Verifying Checksum ... OK
2837 The "bootm" command is used to boot an application that is stored in
2838 memory (RAM or Flash). In case of a Linux kernel image, the contents
2839 of the "bootargs" environment variable is passed to the kernel as
2840 parameters. You can check and modify this variable using the
2841 "printenv" and "setenv" commands:
2844 => printenv bootargs
2845 bootargs=root=/dev/ram
2847 => setenv bootargs root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
2849 => printenv bootargs
2850 bootargs=root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
2853 ## Booting Linux kernel at 40020000 ...
2854 Image Name: 2.2.13 for NFS on TQM850L
2855 Image Type: PowerPC Linux Kernel Image (gzip compressed)
2856 Data Size: 381681 Bytes = 372 kB = 0 MB
2857 Load Address: 00000000
2858 Entry Point: 0000000c
2859 Verifying Checksum ... OK
2860 Uncompressing Kernel Image ... OK
2861 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
2862 Boot arguments: root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
2863 time_init: decrementer frequency = 187500000/60
2864 Calibrating delay loop... 49.77 BogoMIPS
2865 Memory: 15208k available (700k kernel code, 444k data, 32k init) [c0000000,c1000000]
2868 If you want to boot a Linux kernel with initial ram disk, you pass
2869 the memory addresses of both the kernel and the initrd image (PPBCOOT
2870 format!) to the "bootm" command:
2872 => imi 40100000 40200000
2874 ## Checking Image at 40100000 ...
2875 Image Name: 2.2.13 for initrd on TQM850L
2876 Image Type: PowerPC Linux Kernel Image (gzip compressed)
2877 Data Size: 335725 Bytes = 327 kB = 0 MB
2878 Load Address: 00000000
2879 Entry Point: 0000000c
2880 Verifying Checksum ... OK
2882 ## Checking Image at 40200000 ...
2883 Image Name: Simple Ramdisk Image
2884 Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
2885 Data Size: 566530 Bytes = 553 kB = 0 MB
2886 Load Address: 00000000
2887 Entry Point: 00000000
2888 Verifying Checksum ... OK
2890 => bootm 40100000 40200000
2891 ## Booting Linux kernel at 40100000 ...
2892 Image Name: 2.2.13 for initrd on TQM850L
2893 Image Type: PowerPC Linux Kernel Image (gzip compressed)
2894 Data Size: 335725 Bytes = 327 kB = 0 MB
2895 Load Address: 00000000
2896 Entry Point: 0000000c
2897 Verifying Checksum ... OK
2898 Uncompressing Kernel Image ... OK
2899 ## Loading RAMDisk Image at 40200000 ...
2900 Image Name: Simple Ramdisk Image
2901 Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
2902 Data Size: 566530 Bytes = 553 kB = 0 MB
2903 Load Address: 00000000
2904 Entry Point: 00000000
2905 Verifying Checksum ... OK
2906 Loading Ramdisk ... OK
2907 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
2908 Boot arguments: root=/dev/ram
2909 time_init: decrementer frequency = 187500000/60
2910 Calibrating delay loop... 49.77 BogoMIPS
2912 RAMDISK: Compressed image found at block 0
2913 VFS: Mounted root (ext2 filesystem).
2917 More About U-Boot Image Types:
2918 ------------------------------
2920 U-Boot supports the following image types:
2922 "Standalone Programs" are directly runnable in the environment
2923 provided by U-Boot; it is expected that (if they behave
2924 well) you can continue to work in U-Boot after return from
2925 the Standalone Program.
2926 "OS Kernel Images" are usually images of some Embedded OS which
2927 will take over control completely. Usually these programs
2928 will install their own set of exception handlers, device
2929 drivers, set up the MMU, etc. - this means, that you cannot
2930 expect to re-enter U-Boot except by resetting the CPU.
2931 "RAMDisk Images" are more or less just data blocks, and their
2932 parameters (address, size) are passed to an OS kernel that is
2934 "Multi-File Images" contain several images, typically an OS
2935 (Linux) kernel image and one or more data images like
2936 RAMDisks. This construct is useful for instance when you want
2937 to boot over the network using BOOTP etc., where the boot
2938 server provides just a single image file, but you want to get
2939 for instance an OS kernel and a RAMDisk image.
2941 "Multi-File Images" start with a list of image sizes, each
2942 image size (in bytes) specified by an "uint32_t" in network
2943 byte order. This list is terminated by an "(uint32_t)0".
2944 Immediately after the terminating 0 follow the images, one by
2945 one, all aligned on "uint32_t" boundaries (size rounded up to
2946 a multiple of 4 bytes).
2948 "Firmware Images" are binary images containing firmware (like
2949 U-Boot or FPGA images) which usually will be programmed to
2952 "Script files" are command sequences that will be executed by
2953 U-Boot's command interpreter; this feature is especially
2954 useful when you configure U-Boot to use a real shell (hush)
2955 as command interpreter.
2961 One of the features of U-Boot is that you can dynamically load and
2962 run "standalone" applications, which can use some resources of
2963 U-Boot like console I/O functions or interrupt services.
2965 Two simple examples are included with the sources:
2970 'examples/hello_world.c' contains a small "Hello World" Demo
2971 application; it is automatically compiled when you build U-Boot.
2972 It's configured to run at address 0x00040004, so you can play with it
2976 ## Ready for S-Record download ...
2977 ~>examples/hello_world.srec
2978 1 2 3 4 5 6 7 8 9 10 11 ...
2979 [file transfer complete]
2981 ## Start Addr = 0x00040004
2983 => go 40004 Hello World! This is a test.
2984 ## Starting application at 0x00040004 ...
2995 Hit any key to exit ...
2997 ## Application terminated, rc = 0x0
2999 Another example, which demonstrates how to register a CPM interrupt
3000 handler with the U-Boot code, can be found in 'examples/timer.c'.
3001 Here, a CPM timer is set up to generate an interrupt every second.
3002 The interrupt service routine is trivial, just printing a '.'
3003 character, but this is just a demo program. The application can be
3004 controlled by the following keys:
3006 ? - print current values og the CPM Timer registers
3007 b - enable interrupts and start timer
3008 e - stop timer and disable interrupts
3009 q - quit application
3012 ## Ready for S-Record download ...
3013 ~>examples/timer.srec
3014 1 2 3 4 5 6 7 8 9 10 11 ...
3015 [file transfer complete]
3017 ## Start Addr = 0x00040004
3020 ## Starting application at 0x00040004 ...
3023 tgcr @ 0xfff00980, tmr @ 0xfff00990, trr @ 0xfff00994, tcr @ 0xfff00998, tcn @ 0xfff0099c, ter @ 0xfff009b0
3026 [q, b, e, ?] Set interval 1000000 us
3029 [q, b, e, ?] ........
3030 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0xef6, ter=0x0
3033 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x2ad4, ter=0x0
3036 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x1efc, ter=0x0
3039 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x169d, ter=0x0
3041 [q, b, e, ?] ...Stopping timer
3043 [q, b, e, ?] ## Application terminated, rc = 0x0
3049 Over time, many people have reported problems when trying to use the
3050 "minicom" terminal emulation program for serial download. I (wd)
3051 consider minicom to be broken, and recommend not to use it. Under
3052 Unix, I recommend to use C-Kermit for general purpose use (and
3053 especially for kermit binary protocol download ("loadb" command), and
3054 use "cu" for S-Record download ("loads" command).
3056 Nevertheless, if you absolutely want to use it try adding this
3057 configuration to your "File transfer protocols" section:
3059 Name Program Name U/D FullScr IO-Red. Multi
3060 X kermit /usr/bin/kermit -i -l %l -s Y U Y N N
3061 Y kermit /usr/bin/kermit -i -l %l -r N D Y N N
3067 Starting at version 0.9.2, U-Boot supports NetBSD both as host
3068 (build U-Boot) and target system (boots NetBSD/mpc8xx).
3070 Building requires a cross environment; it is known to work on
3071 NetBSD/i386 with the cross-powerpc-netbsd-1.3 package (you will also
3072 need gmake since the Makefiles are not compatible with BSD make).
3073 Note that the cross-powerpc package does not install include files;
3074 attempting to build U-Boot will fail because <machine/ansi.h> is
3075 missing. This file has to be installed and patched manually:
3077 # cd /usr/pkg/cross/powerpc-netbsd/include
3079 # ln -s powerpc machine
3080 # cp /usr/src/sys/arch/powerpc/include/ansi.h powerpc/ansi.h
3081 # ${EDIT} powerpc/ansi.h ## must remove __va_list, _BSD_VA_LIST
3083 Native builds *don't* work due to incompatibilities between native
3084 and U-Boot include files.
3086 Booting assumes that (the first part of) the image booted is a
3087 stage-2 loader which in turn loads and then invokes the kernel
3088 proper. Loader sources will eventually appear in the NetBSD source
3089 tree (probably in sys/arc/mpc8xx/stand/u-boot_stage2/); in the
3090 meantime, see ftp://ftp.denx.de/pub/u-boot/ppcboot_stage2.tar.gz
3093 Implementation Internals:
3094 =========================
3096 The following is not intended to be a complete description of every
3097 implementation detail. However, it should help to understand the
3098 inner workings of U-Boot and make it easier to port it to custom
3102 Initial Stack, Global Data:
3103 ---------------------------
3105 The implementation of U-Boot is complicated by the fact that U-Boot
3106 starts running out of ROM (flash memory), usually without access to
3107 system RAM (because the memory controller is not initialized yet).
3108 This means that we don't have writable Data or BSS segments, and BSS
3109 is not initialized as zero. To be able to get a C environment working
3110 at all, we have to allocate at least a minimal stack. Implementation
3111 options for this are defined and restricted by the CPU used: Some CPU
3112 models provide on-chip memory (like the IMMR area on MPC8xx and
3113 MPC826x processors), on others (parts of) the data cache can be
3114 locked as (mis-) used as memory, etc.
3116 Chris Hallinan posted a good summary of these issues to the
3117 u-boot-users mailing list:
3119 Subject: RE: [U-Boot-Users] RE: More On Memory Bank x (nothingness)?
3120 From: "Chris Hallinan" <clh@net1plus.com>
3121 Date: Mon, 10 Feb 2003 16:43:46 -0500 (22:43 MET)
3124 Correct me if I'm wrong, folks, but the way I understand it
3125 is this: Using DCACHE as initial RAM for Stack, etc, does not
3126 require any physical RAM backing up the cache. The cleverness
3127 is that the cache is being used as a temporary supply of
3128 necessary storage before the SDRAM controller is setup. It's
3129 beyond the scope of this list to expain the details, but you
3130 can see how this works by studying the cache architecture and
3131 operation in the architecture and processor-specific manuals.
3133 OCM is On Chip Memory, which I believe the 405GP has 4K. It
3134 is another option for the system designer to use as an
3135 initial stack/ram area prior to SDRAM being available. Either
3136 option should work for you. Using CS 4 should be fine if your
3137 board designers haven't used it for something that would
3138 cause you grief during the initial boot! It is frequently not
3141 CFG_INIT_RAM_ADDR should be somewhere that won't interfere
3142 with your processor/board/system design. The default value
3143 you will find in any recent u-boot distribution in
3144 walnut.h should work for you. I'd set it to a value larger
3145 than your SDRAM module. If you have a 64MB SDRAM module, set
3146 it above 400_0000. Just make sure your board has no resources
3147 that are supposed to respond to that address! That code in
3148 start.S has been around a while and should work as is when
3149 you get the config right.
3154 It is essential to remember this, since it has some impact on the C
3155 code for the initialization procedures:
3157 * Initialized global data (data segment) is read-only. Do not attempt
3160 * Do not use any unitialized global data (or implicitely initialized
3161 as zero data - BSS segment) at all - this is undefined, initiali-
3162 zation is performed later (when relocating to RAM).
3164 * Stack space is very limited. Avoid big data buffers or things like
3167 Having only the stack as writable memory limits means we cannot use
3168 normal global data to share information beween the code. But it
3169 turned out that the implementation of U-Boot can be greatly
3170 simplified by making a global data structure (gd_t) available to all
3171 functions. We could pass a pointer to this data as argument to _all_
3172 functions, but this would bloat the code. Instead we use a feature of
3173 the GCC compiler (Global Register Variables) to share the data: we
3174 place a pointer (gd) to the global data into a register which we
3175 reserve for this purpose.
3177 When choosing a register for such a purpose we are restricted by the
3178 relevant (E)ABI specifications for the current architecture, and by
3179 GCC's implementation.
3181 For PowerPC, the following registers have specific use:
3184 R3-R4: parameter passing and return values
3185 R5-R10: parameter passing
3186 R13: small data area pointer
3190 (U-Boot also uses R14 as internal GOT pointer.)
3192 ==> U-Boot will use R29 to hold a pointer to the global data
3194 Note: on PPC, we could use a static initializer (since the
3195 address of the global data structure is known at compile time),
3196 but it turned out that reserving a register results in somewhat
3197 smaller code - although the code savings are not that big (on
3198 average for all boards 752 bytes for the whole U-Boot image,
3199 624 text + 127 data).
3201 On ARM, the following registers are used:
3203 R0: function argument word/integer result
3204 R1-R3: function argument word
3206 R10: stack limit (used only if stack checking if enabled)
3207 R11: argument (frame) pointer
3208 R12: temporary workspace
3211 R15: program counter
3213 ==> U-Boot will use R8 to hold a pointer to the global data
3219 U-Boot runs in system state and uses physical addresses, i.e. the
3220 MMU is not used either for address mapping nor for memory protection.
3222 The available memory is mapped to fixed addresses using the memory
3223 controller. In this process, a contiguous block is formed for each
3224 memory type (Flash, SDRAM, SRAM), even when it consists of several
3225 physical memory banks.
3227 U-Boot is installed in the first 128 kB of the first Flash bank (on
3228 TQM8xxL modules this is the range 0x40000000 ... 0x4001FFFF). After
3229 booting and sizing and initializing DRAM, the code relocates itself
3230 to the upper end of DRAM. Immediately below the U-Boot code some
3231 memory is reserved for use by malloc() [see CFG_MALLOC_LEN
3232 configuration setting]. Below that, a structure with global Board
3233 Info data is placed, followed by the stack (growing downward).
3235 Additionally, some exception handler code is copied to the low 8 kB
3236 of DRAM (0x00000000 ... 0x00001FFF).
3238 So a typical memory configuration with 16 MB of DRAM could look like
3241 0x0000 0000 Exception Vector code
3244 0x0000 2000 Free for Application Use
3250 0x00FB FF20 Monitor Stack (Growing downward)
3251 0x00FB FFAC Board Info Data and permanent copy of global data
3252 0x00FC 0000 Malloc Arena
3255 0x00FE 0000 RAM Copy of Monitor Code
3256 ... eventually: LCD or video framebuffer
3257 ... eventually: pRAM (Protected RAM - unchanged by reset)
3258 0x00FF FFFF [End of RAM]
3261 System Initialization:
3262 ----------------------
3264 In the reset configuration, U-Boot starts at the reset entry point
3265 (on most PowerPC systens at address 0x00000100). Because of the reset
3266 configuration for CS0# this is a mirror of the onboard Flash memory.
3267 To be able to re-map memory U-Boot then jumps to its link address.
3268 To be able to implement the initialization code in C, a (small!)
3269 initial stack is set up in the internal Dual Ported RAM (in case CPUs
3270 which provide such a feature like MPC8xx or MPC8260), or in a locked
3271 part of the data cache. After that, U-Boot initializes the CPU core,
3272 the caches and the SIU.
3274 Next, all (potentially) available memory banks are mapped using a
3275 preliminary mapping. For example, we put them on 512 MB boundaries
3276 (multiples of 0x20000000: SDRAM on 0x00000000 and 0x20000000, Flash
3277 on 0x40000000 and 0x60000000, SRAM on 0x80000000). Then UPM A is
3278 programmed for SDRAM access. Using the temporary configuration, a
3279 simple memory test is run that determines the size of the SDRAM
3282 When there is more than one SDRAM bank, and the banks are of
3283 different size, the largest is mapped first. For equal size, the first
3284 bank (CS2#) is mapped first. The first mapping is always for address
3285 0x00000000, with any additional banks following immediately to create
3286 contiguous memory starting from 0.
3288 Then, the monitor installs itself at the upper end of the SDRAM area
3289 and allocates memory for use by malloc() and for the global Board
3290 Info data; also, the exception vector code is copied to the low RAM
3291 pages, and the final stack is set up.
3293 Only after this relocation will you have a "normal" C environment;
3294 until that you are restricted in several ways, mostly because you are
3295 running from ROM, and because the code will have to be relocated to a
3299 U-Boot Porting Guide:
3300 ----------------------
3302 [Based on messages by Jerry Van Baren in the U-Boot-Users mailing
3306 int main (int argc, char *argv[])
3308 sighandler_t no_more_time;
3310 signal (SIGALRM, no_more_time);
3311 alarm (PROJECT_DEADLINE - toSec (3 * WEEK));
3313 if (available_money > available_manpower) {
3314 pay consultant to port U-Boot;
3318 Download latest U-Boot source;
3320 Subscribe to u-boot-users mailing list;
3323 email ("Hi, I am new to U-Boot, how do I get started?");
3327 Read the README file in the top level directory;
3328 Read http://www.denx.de/twiki/bin/view/DULG/Manual ;
3329 Read the source, Luke;
3332 if (available_money > toLocalCurrency ($2500)) {
3335 Add a lot of aggravation and time;
3338 Create your own board support subdirectory;
3340 Create your own board config file;
3344 Add / modify source code;
3348 email ("Hi, I am having problems...");
3350 Send patch file to Wolfgang;
3355 void no_more_time (int sig)
3364 All contributions to U-Boot should conform to the Linux kernel
3365 coding style; see the file "Documentation/CodingStyle" in your Linux
3366 kernel source directory.
3368 Please note that U-Boot is implemented in C (and to some small parts
3369 in Assembler); no C++ is used, so please do not use C++ style
3370 comments (//) in your code.
3372 Please also stick to the following formatting rules:
3373 - remove any trailing white space
3374 - use TAB characters for indentation, not spaces
3375 - make sure NOT to use DOS '\r\n' line feeds
3376 - do not add more than 2 empty lines to source files
3377 - do not add trailing empty lines to source files
3379 Submissions which do not conform to the standards may be returned
3380 with a request to reformat the changes.
3386 Since the number of patches for U-Boot is growing, we need to
3387 establish some rules. Submissions which do not conform to these rules
3388 may be rejected, even when they contain important and valuable stuff.
3390 Patches shall be sent to the u-boot-users mailing list.
3392 When you send a patch, please include the following information with
3395 * For bug fixes: a description of the bug and how your patch fixes
3396 this bug. Please try to include a way of demonstrating that the
3397 patch actually fixes something.
3399 * For new features: a description of the feature and your
3402 * A CHANGELOG entry as plaintext (separate from the patch)
3404 * For major contributions, your entry to the CREDITS file
3406 * When you add support for a new board, don't forget to add this
3407 board to the MAKEALL script, too.
3409 * If your patch adds new configuration options, don't forget to
3410 document these in the README file.
3412 * The patch itself. If you are accessing the CVS repository use "cvs
3413 update; cvs diff -puRN"; else, use "diff -purN OLD NEW". If your
3414 version of diff does not support these options, then get the latest
3415 version of GNU diff.
3417 The current directory when running this command shall be the top
3418 level directory of the U-Boot source tree, or it's parent directory
3419 (i. e. please make sure that your patch includes sufficient
3420 directory information for the affected files).
3422 We accept patches as plain text, MIME attachments or as uuencoded
3425 * If one logical set of modifications affects or creates several
3426 files, all these changes shall be submitted in a SINGLE patch file.
3428 * Changesets that contain different, unrelated modifications shall be
3429 submitted as SEPARATE patches, one patch per changeset.
3434 * Before sending the patch, run the MAKEALL script on your patched
3435 source tree and make sure that no errors or warnings are reported
3436 for any of the boards.
3438 * Keep your modifications to the necessary minimum: A patch
3439 containing several unrelated changes or arbitrary reformats will be
3440 returned with a request to re-formatting / split it.
3442 * If you modify existing code, make sure that your new code does not
3443 add to the memory footprint of the code ;-) Small is beautiful!
3444 When adding new features, these should compile conditionally only
3445 (using #ifdef), and the resulting code with the new feature
3446 disabled must not need more memory than the old code without your
3449 * Remember that there is a size limit of 40 kB per message on the
3450 u-boot-users mailing list. Compression may help.
projects / platform / kernel / u-boot.git / blob