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 - imx Files specific to Freescale MC9328 i.MX CPUs
130 - s3c24x0 Files specific to Samsung S3C24X0 CPUs
131 - arm925t Files specific to ARM 925 CPUs
132 - arm926ejs Files specific to ARM 926 CPUs
133 - arm1136 Files specific to ARM 1136 CPUs
134 - at91rm9200 Files specific to Atmel AT91RM9200 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_MPC8560ADS CONFIG_TQM850L
291 CONFIG_ERIC CONFIG_MUSENKI CONFIG_TQM855L
292 CONFIG_ESTEEM192E CONFIG_MVS1 CONFIG_TQM860L
293 CONFIG_ETX094 CONFIG_NETPHONE CONFIG_TTTech
294 CONFIG_EVB64260 CONFIG_NETTA CONFIG_UTX8245
295 CONFIG_FADS823 CONFIG_NETVIA CONFIG_V37
296 CONFIG_FADS850SAR CONFIG_NX823 CONFIG_W7OLMC
297 CONFIG_FADS860T CONFIG_OCRTC CONFIG_W7OLMG
298 CONFIG_FLAGADM CONFIG_ORSG CONFIG_WALNUT405
299 CONFIG_FPS850L CONFIG_OXC CONFIG_ZPC1900
300 CONFIG_FPS860L 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 CFG_CMD_SETGETDCR Support for DCR Register access (4xx only)
631 CFG_CMD_SPI * SPI serial bus support
632 CFG_CMD_USB * USB support
633 CFG_CMD_VFD * VFD support (TRAB)
634 CFG_CMD_BSP * Board SPecific functions
635 CFG_CMD_CDP * Cisco Discover Protocol support
636 -----------------------------------------------
639 CONFIG_CMD_DFL Default configuration; at the moment
640 this is includes all commands, except
641 the ones marked with "*" in the list
644 If you don't define CONFIG_COMMANDS it defaults to
645 CONFIG_CMD_DFL in include/cmd_confdefs.h. A board can
646 override the default settings in the respective
649 EXAMPLE: If you want all functions except of network
650 support you can write:
652 #define CONFIG_COMMANDS (CFG_CMD_ALL & ~CFG_CMD_NET)
655 Note: Don't enable the "icache" and "dcache" commands
656 (configuration option CFG_CMD_CACHE) unless you know
657 what you (and your U-Boot users) are doing. Data
658 cache cannot be enabled on systems like the 8xx or
659 8260 (where accesses to the IMMR region must be
660 uncached), and it cannot be disabled on all other
661 systems where we (mis-) use the data cache to hold an
662 initial stack and some data.
665 XXX - this list needs to get updated!
669 If this variable is defined, it enables watchdog
670 support. There must be support in the platform specific
671 code for a watchdog. For the 8xx and 8260 CPUs, the
672 SIU Watchdog feature is enabled in the SYPCR
676 CONFIG_VERSION_VARIABLE
677 If this variable is defined, an environment variable
678 named "ver" is created by U-Boot showing the U-Boot
679 version as printed by the "version" command.
680 This variable is readonly.
684 When CFG_CMD_DATE is selected, the type of the RTC
685 has to be selected, too. Define exactly one of the
688 CONFIG_RTC_MPC8xx - use internal RTC of MPC8xx
689 CONFIG_RTC_PCF8563 - use Philips PCF8563 RTC
690 CONFIG_RTC_MC146818 - use MC146818 RTC
691 CONFIG_RTC_DS1307 - use Maxim, Inc. DS1307 RTC
692 CONFIG_RTC_DS1337 - use Maxim, Inc. DS1337 RTC
693 CONFIG_RTC_DS1338 - use Maxim, Inc. DS1338 RTC
694 CONFIG_RTC_DS164x - use Dallas DS164x RTC
695 CONFIG_RTC_MAX6900 - use Maxim, Inc. MAX6900 RTC
697 Note that if the RTC uses I2C, then the I2C interface
698 must also be configured. See I2C Support, below.
702 When CONFIG_TIMESTAMP is selected, the timestamp
703 (date and time) of an image is printed by image
704 commands like bootm or iminfo. This option is
705 automatically enabled when you select CFG_CMD_DATE .
708 CONFIG_MAC_PARTITION and/or CONFIG_DOS_PARTITION
709 and/or CONFIG_ISO_PARTITION
711 If IDE or SCSI support is enabled (CFG_CMD_IDE or
712 CFG_CMD_SCSI) you must configure support for at least
713 one partition type as well.
716 CONFIG_IDE_RESET_ROUTINE - this is defined in several
717 board configurations files but used nowhere!
719 CONFIG_IDE_RESET - is this is defined, IDE Reset will
720 be performed by calling the function
721 ide_set_reset(int reset)
722 which has to be defined in a board specific file
727 Set this to enable ATAPI support.
732 Set this to enable support for disks larger than 137GB
733 Also look at CFG_64BIT_LBA ,CFG_64BIT_VSPRINTF and CFG_64BIT_STRTOUL
734 Whithout these , LBA48 support uses 32bit variables and will 'only'
735 support disks up to 2.1TB.
738 When enabled, makes the IDE subsystem use 64bit sector addresses.
742 At the moment only there is only support for the
743 SYM53C8XX SCSI controller; define
744 CONFIG_SCSI_SYM53C8XX to enable it.
746 CFG_SCSI_MAX_LUN [8], CFG_SCSI_MAX_SCSI_ID [7] and
747 CFG_SCSI_MAX_DEVICE [CFG_SCSI_MAX_SCSI_ID *
748 CFG_SCSI_MAX_LUN] can be adjusted to define the
749 maximum numbers of LUNs, SCSI ID's and target
751 CFG_SCSI_SYM53C8XX_CCF to fix clock timing (80Mhz)
753 - NETWORK Support (PCI):
755 Support for Intel 8254x gigabit chips.
758 Support for Intel 82557/82559/82559ER chips.
759 Optional CONFIG_EEPRO100_SROM_WRITE enables eeprom
760 write routine for first time initialisation.
763 Support for Digital 2114x chips.
764 Optional CONFIG_TULIP_SELECT_MEDIA for board specific
765 modem chip initialisation (KS8761/QS6611).
768 Support for National dp83815 chips.
771 Support for National dp8382[01] gigabit chips.
773 - NETWORK Support (other):
775 CONFIG_DRIVER_LAN91C96
776 Support for SMSC's LAN91C96 chips.
779 Define this to hold the physical address
780 of the LAN91C96's I/O space
782 CONFIG_LAN91C96_USE_32_BIT
783 Define this to enable 32 bit addressing
785 CONFIG_DRIVER_SMC91111
786 Support for SMSC's LAN91C111 chip
789 Define this to hold the physical address
790 of the device (I/O space)
792 CONFIG_SMC_USE_32_BIT
793 Define this if data bus is 32 bits
795 CONFIG_SMC_USE_IOFUNCS
796 Define this to use i/o functions instead of macros
797 (some hardware wont work with macros)
800 At the moment only the UHCI host controller is
801 supported (PIP405, MIP405, MPC5200); define
802 CONFIG_USB_UHCI to enable it.
803 define CONFIG_USB_KEYBOARD to enable the USB Keyboard
804 and define CONFIG_USB_STORAGE to enable the USB
807 Supported are USB Keyboards and USB Floppy drives
809 MPC5200 USB requires additional defines:
811 for 528 MHz Clock: 0x0001bbbb
813 for differential drivers: 0x00001000
814 for single ended drivers: 0x00005000
818 The MMC controller on the Intel PXA is supported. To
819 enable this define CONFIG_MMC. The MMC can be
820 accessed from the boot prompt by mapping the device
821 to physical memory similar to flash. Command line is
822 enabled with CFG_CMD_MMC. The MMC driver also works with
823 the FAT fs. This is enabled with CFG_CMD_FAT.
825 - Journaling Flash filesystem support:
826 CONFIG_JFFS2_NAND, CONFIG_JFFS2_NAND_OFF, CONFIG_JFFS2_NAND_SIZE,
827 CONFIG_JFFS2_NAND_DEV
828 Define these for a default partition on a NAND device
830 CFG_JFFS2_FIRST_SECTOR,
831 CFG_JFFS2_FIRST_BANK, CFG_JFFS2_NUM_BANKS
832 Define these for a default partition on a NOR device
835 Define this to create an own partition. You have to provide a
836 function struct part_info* jffs2_part_info(int part_num)
838 If you define only one JFFS2 partition you may also want to
839 #define CFG_JFFS_SINGLE_PART 1
840 to disable the command chpart. This is the default when you
841 have not defined a custom partition
846 Define this to enable standard (PC-Style) keyboard
850 Standard PC keyboard driver with US (is default) and
851 GERMAN key layout (switch via environment 'keymap=de') support.
852 Export function i8042_kbd_init, i8042_tstc and i8042_getc
853 for cfb_console. Supports cursor blinking.
858 Define this to enable video support (for output to
863 Enable Chips & Technologies 69000 Video chip
865 CONFIG_VIDEO_SMI_LYNXEM
866 Enable Silicon Motion SMI 712/710/810 Video chip. The
867 video output is selected via environment 'videoout'
868 (1 = LCD and 2 = CRT). If videoout is undefined, CRT is
871 For the CT69000 and SMI_LYNXEM drivers, videomode is
872 selected via environment 'videomode'. Two diferent ways
874 - "videomode=num" 'num' is a standard LiLo mode numbers.
875 Following standard modes are supported (* is default):
877 Colors 640x480 800x600 1024x768 1152x864 1280x1024
878 -------------+---------------------------------------------
879 8 bits | 0x301* 0x303 0x305 0x161 0x307
880 15 bits | 0x310 0x313 0x316 0x162 0x319
881 16 bits | 0x311 0x314 0x317 0x163 0x31A
882 24 bits | 0x312 0x315 0x318 ? 0x31B
883 -------------+---------------------------------------------
884 (i.e. setenv videomode 317; saveenv; reset;)
886 - "videomode=bootargs" all the video parameters are parsed
887 from the bootargs. (See drivers/videomodes.c)
890 CONFIG_VIDEO_SED13806
891 Enable Epson SED13806 driver. This driver supports 8bpp
892 and 16bpp modes defined by CONFIG_VIDEO_SED13806_8BPP
893 or CONFIG_VIDEO_SED13806_16BPP
898 Define this to enable a custom keyboard support.
899 This simply calls drv_keyboard_init() which must be
900 defined in your board-specific files.
901 The only board using this so far is RBC823.
903 - LCD Support: CONFIG_LCD
905 Define this to enable LCD support (for output to LCD
906 display); also select one of the supported displays
907 by defining one of these:
909 CONFIG_NEC_NL6448AC33:
911 NEC NL6448AC33-18. Active, color, single scan.
913 CONFIG_NEC_NL6448BC20
915 NEC NL6448BC20-08. 6.5", 640x480.
916 Active, color, single scan.
918 CONFIG_NEC_NL6448BC33_54
920 NEC NL6448BC33-54. 10.4", 640x480.
921 Active, color, single scan.
925 Sharp 320x240. Active, color, single scan.
926 It isn't 16x9, and I am not sure what it is.
928 CONFIG_SHARP_LQ64D341
930 Sharp LQ64D341 display, 640x480.
931 Active, color, single scan.
935 HLD1045 display, 640x480.
936 Active, color, single scan.
940 Optrex CBL50840-2 NF-FW 99 22 M5
942 Hitachi LMG6912RPFC-00T
946 320x240. Black & white.
948 Normally display is black on white background; define
949 CFG_WHITE_ON_BLACK to get it inverted.
951 - Splash Screen Support: CONFIG_SPLASH_SCREEN
953 If this option is set, the environment is checked for
954 a variable "splashimage". If found, the usual display
955 of logo, copyright and system information on the LCD
956 is suppressed and the BMP image at the address
957 specified in "splashimage" is loaded instead. The
958 console is redirected to the "nulldev", too. This
959 allows for a "silent" boot where a splash screen is
960 loaded very quickly after power-on.
962 - Compression support:
965 If this option is set, support for bzip2 compressed
966 images is included. If not, only uncompressed and gzip
967 compressed images are supported.
969 NOTE: the bzip2 algorithm requires a lot of RAM, so
970 the malloc area (as defined by CFG_MALLOC_LEN) should
976 The address of PHY on MII bus.
978 CONFIG_PHY_CLOCK_FREQ (ppc4xx)
980 The clock frequency of the MII bus
984 If this option is set, support for speed/duplex
985 detection of Gigabit PHY is included.
987 CONFIG_PHY_RESET_DELAY
989 Some PHY like Intel LXT971A need extra delay after
990 reset before any MII register access is possible.
991 For such PHY, set this option to the usec delay
992 required. (minimum 300usec for LXT971A)
994 CONFIG_PHY_CMD_DELAY (ppc4xx)
996 Some PHY like Intel LXT971A need extra delay after
997 command issued before MII status register can be read
1004 Define a default value for ethernet address to use
1005 for the respective ethernet interface, in case this
1006 is not determined automatically.
1011 Define a default value for the IP address to use for
1012 the default ethernet interface, in case this is not
1013 determined through e.g. bootp.
1015 - Server IP address:
1018 Defines a default value for theIP address of a TFTP
1019 server to contact when using the "tftboot" command.
1021 - BOOTP Recovery Mode:
1022 CONFIG_BOOTP_RANDOM_DELAY
1024 If you have many targets in a network that try to
1025 boot using BOOTP, you may want to avoid that all
1026 systems send out BOOTP requests at precisely the same
1027 moment (which would happen for instance at recovery
1028 from a power failure, when all systems will try to
1029 boot, thus flooding the BOOTP server. Defining
1030 CONFIG_BOOTP_RANDOM_DELAY causes a random delay to be
1031 inserted before sending out BOOTP requests. The
1032 following delays are insterted then:
1034 1st BOOTP request: delay 0 ... 1 sec
1035 2nd BOOTP request: delay 0 ... 2 sec
1036 3rd BOOTP request: delay 0 ... 4 sec
1038 BOOTP requests: delay 0 ... 8 sec
1040 - DHCP Advanced Options:
1043 You can fine tune the DHCP functionality by adding
1044 these flags to the CONFIG_BOOTP_MASK define:
1046 CONFIG_BOOTP_DNS2 - If a DHCP client requests the DNS
1047 serverip from a DHCP server, it is possible that more
1048 than one DNS serverip is offered to the client.
1049 If CONFIG_BOOTP_DNS2 is enabled, the secondary DNS
1050 serverip will be stored in the additional environment
1051 variable "dnsip2". The first DNS serverip is always
1052 stored in the variable "dnsip", when CONFIG_BOOTP_DNS
1053 is added to the CONFIG_BOOTP_MASK.
1055 CONFIG_BOOTP_SEND_HOSTNAME - Some DHCP servers are capable
1056 to do a dynamic update of a DNS server. To do this, they
1057 need the hostname of the DHCP requester.
1058 If CONFIG_BOOP_SEND_HOSTNAME is added to the
1059 CONFIG_BOOTP_MASK, the content of the "hostname"
1060 environment variable is passed as option 12 to
1064 CONFIG_CDP_DEVICE_ID
1066 The device id used in CDP trigger frames.
1068 CONFIG_CDP_DEVICE_ID_PREFIX
1070 A two character string which is prefixed to the MAC address
1075 A printf format string which contains the ascii name of
1076 the port. Normally is set to "eth%d" which sets
1077 eth0 for the first ethernet, eth1 for the second etc.
1079 CONFIG_CDP_CAPABILITIES
1081 A 32bit integer which indicates the device capabilities;
1082 0x00000010 for a normal host which does not forwards.
1086 An ascii string containing the version of the software.
1090 An ascii string containing the name of the platform.
1094 A 32bit integer sent on the trigger.
1096 CONFIG_CDP_POWER_CONSUMPTION
1098 A 16bit integer containing the power consumption of the
1099 device in .1 of milliwatts.
1101 CONFIG_CDP_APPLIANCE_VLAN_TYPE
1103 A byte containing the id of the VLAN.
1105 - Status LED: CONFIG_STATUS_LED
1107 Several configurations allow to display the current
1108 status using a LED. For instance, the LED will blink
1109 fast while running U-Boot code, stop blinking as
1110 soon as a reply to a BOOTP request was received, and
1111 start blinking slow once the Linux kernel is running
1112 (supported by a status LED driver in the Linux
1113 kernel). Defining CONFIG_STATUS_LED enables this
1116 - CAN Support: CONFIG_CAN_DRIVER
1118 Defining CONFIG_CAN_DRIVER enables CAN driver support
1119 on those systems that support this (optional)
1120 feature, like the TQM8xxL modules.
1122 - I2C Support: CONFIG_HARD_I2C | CONFIG_SOFT_I2C
1124 These enable I2C serial bus commands. Defining either of
1125 (but not both of) CONFIG_HARD_I2C or CONFIG_SOFT_I2C will
1126 include the appropriate I2C driver for the selected cpu.
1128 This will allow you to use i2c commands at the u-boot
1129 command line (as long as you set CFG_CMD_I2C in
1130 CONFIG_COMMANDS) and communicate with i2c based realtime
1131 clock chips. See common/cmd_i2c.c for a description of the
1132 command line interface.
1134 CONFIG_HARD_I2C selects the CPM hardware driver for I2C.
1136 CONFIG_SOFT_I2C configures u-boot to use a software (aka
1137 bit-banging) driver instead of CPM or similar hardware
1140 There are several other quantities that must also be
1141 defined when you define CONFIG_HARD_I2C or CONFIG_SOFT_I2C.
1143 In both cases you will need to define CFG_I2C_SPEED
1144 to be the frequency (in Hz) at which you wish your i2c bus
1145 to run and CFG_I2C_SLAVE to be the address of this node (ie
1146 the cpu's i2c node address).
1148 Now, the u-boot i2c code for the mpc8xx (cpu/mpc8xx/i2c.c)
1149 sets the cpu up as a master node and so its address should
1150 therefore be cleared to 0 (See, eg, MPC823e User's Manual
1151 p.16-473). So, set CFG_I2C_SLAVE to 0.
1153 That's all that's required for CONFIG_HARD_I2C.
1155 If you use the software i2c interface (CONFIG_SOFT_I2C)
1156 then the following macros need to be defined (examples are
1157 from include/configs/lwmon.h):
1161 (Optional). Any commands necessary to enable the I2C
1162 controller or configure ports.
1164 eg: #define I2C_INIT (immr->im_cpm.cp_pbdir |= PB_SCL)
1168 (Only for MPC8260 CPU). The I/O port to use (the code
1169 assumes both bits are on the same port). Valid values
1170 are 0..3 for ports A..D.
1174 The code necessary to make the I2C data line active
1175 (driven). If the data line is open collector, this
1178 eg: #define I2C_ACTIVE (immr->im_cpm.cp_pbdir |= PB_SDA)
1182 The code necessary to make the I2C data line tri-stated
1183 (inactive). If the data line is open collector, this
1186 eg: #define I2C_TRISTATE (immr->im_cpm.cp_pbdir &= ~PB_SDA)
1190 Code that returns TRUE if the I2C data line is high,
1193 eg: #define I2C_READ ((immr->im_cpm.cp_pbdat & PB_SDA) != 0)
1197 If <bit> is TRUE, sets the I2C data line high. If it
1198 is FALSE, it clears it (low).
1200 eg: #define I2C_SDA(bit) \
1201 if(bit) immr->im_cpm.cp_pbdat |= PB_SDA; \
1202 else immr->im_cpm.cp_pbdat &= ~PB_SDA
1206 If <bit> is TRUE, sets the I2C clock line high. If it
1207 is FALSE, it clears it (low).
1209 eg: #define I2C_SCL(bit) \
1210 if(bit) immr->im_cpm.cp_pbdat |= PB_SCL; \
1211 else immr->im_cpm.cp_pbdat &= ~PB_SCL
1215 This delay is invoked four times per clock cycle so this
1216 controls the rate of data transfer. The data rate thus
1217 is 1 / (I2C_DELAY * 4). Often defined to be something
1220 #define I2C_DELAY udelay(2)
1224 When a board is reset during an i2c bus transfer
1225 chips might think that the current transfer is still
1226 in progress. On some boards it is possible to access
1227 the i2c SCLK line directly, either by using the
1228 processor pin as a GPIO or by having a second pin
1229 connected to the bus. If this option is defined a
1230 custom i2c_init_board() routine in boards/xxx/board.c
1231 is run early in the boot sequence.
1233 CONFIG_I2CFAST (PPC405GP|PPC405EP only)
1235 This option enables configuration of bi_iic_fast[] flags
1236 in u-boot bd_info structure based on u-boot environment
1237 variable "i2cfast". (see also i2cfast)
1239 - SPI Support: CONFIG_SPI
1241 Enables SPI driver (so far only tested with
1242 SPI EEPROM, also an instance works with Crystal A/D and
1243 D/As on the SACSng board)
1247 Enables extended (16-bit) SPI EEPROM addressing.
1248 (symmetrical to CONFIG_I2C_X)
1252 Enables a software (bit-bang) SPI driver rather than
1253 using hardware support. This is a general purpose
1254 driver that only requires three general I/O port pins
1255 (two outputs, one input) to function. If this is
1256 defined, the board configuration must define several
1257 SPI configuration items (port pins to use, etc). For
1258 an example, see include/configs/sacsng.h.
1260 - FPGA Support: CONFIG_FPGA_COUNT
1262 Specify the number of FPGA devices to support.
1266 Used to specify the types of FPGA devices. For example,
1267 #define CONFIG_FPGA CFG_XILINX_VIRTEX2
1269 CFG_FPGA_PROG_FEEDBACK
1271 Enable printing of hash marks during FPGA configuration.
1275 Enable checks on FPGA configuration interface busy
1276 status by the configuration function. This option
1277 will require a board or device specific function to
1282 If defined, a function that provides delays in the FPGA
1283 configuration driver.
1285 CFG_FPGA_CHECK_CTRLC
1286 Allow Control-C to interrupt FPGA configuration
1288 CFG_FPGA_CHECK_ERROR
1290 Check for configuration errors during FPGA bitfile
1291 loading. For example, abort during Virtex II
1292 configuration if the INIT_B line goes low (which
1293 indicated a CRC error).
1297 Maximum time to wait for the INIT_B line to deassert
1298 after PROB_B has been deasserted during a Virtex II
1299 FPGA configuration sequence. The default time is 500
1304 Maximum time to wait for BUSY to deassert during
1305 Virtex II FPGA configuration. The default is 5 mS.
1307 CFG_FPGA_WAIT_CONFIG
1309 Time to wait after FPGA configuration. The default is
1312 - Configuration Management:
1315 If defined, this string will be added to the U-Boot
1316 version information (U_BOOT_VERSION)
1318 - Vendor Parameter Protection:
1320 U-Boot considers the values of the environment
1321 variables "serial#" (Board Serial Number) and
1322 "ethaddr" (Ethernet Address) to be parameters that
1323 are set once by the board vendor / manufacturer, and
1324 protects these variables from casual modification by
1325 the user. Once set, these variables are read-only,
1326 and write or delete attempts are rejected. You can
1327 change this behviour:
1329 If CONFIG_ENV_OVERWRITE is #defined in your config
1330 file, the write protection for vendor parameters is
1331 completely disabled. Anybody can change or delete
1334 Alternatively, if you #define _both_ CONFIG_ETHADDR
1335 _and_ CONFIG_OVERWRITE_ETHADDR_ONCE, a default
1336 ethernet address is installed in the environment,
1337 which can be changed exactly ONCE by the user. [The
1338 serial# is unaffected by this, i. e. it remains
1344 Define this variable to enable the reservation of
1345 "protected RAM", i. e. RAM which is not overwritten
1346 by U-Boot. Define CONFIG_PRAM to hold the number of
1347 kB you want to reserve for pRAM. You can overwrite
1348 this default value by defining an environment
1349 variable "pram" to the number of kB you want to
1350 reserve. Note that the board info structure will
1351 still show the full amount of RAM. If pRAM is
1352 reserved, a new environment variable "mem" will
1353 automatically be defined to hold the amount of
1354 remaining RAM in a form that can be passed as boot
1355 argument to Linux, for instance like that:
1357 setenv bootargs ... mem=\$(mem)
1360 This way you can tell Linux not to use this memory,
1361 either, which results in a memory region that will
1362 not be affected by reboots.
1364 *WARNING* If your board configuration uses automatic
1365 detection of the RAM size, you must make sure that
1366 this memory test is non-destructive. So far, the
1367 following board configurations are known to be
1370 ETX094, IVMS8, IVML24, SPD8xx, TQM8xxL,
1371 HERMES, IP860, RPXlite, LWMON, LANTEC,
1372 PCU_E, FLAGADM, TQM8260
1377 Define this variable to stop the system in case of a
1378 fatal error, so that you have to reset it manually.
1379 This is probably NOT a good idea for an embedded
1380 system where you want to system to reboot
1381 automatically as fast as possible, but it may be
1382 useful during development since you can try to debug
1383 the conditions that lead to the situation.
1385 CONFIG_NET_RETRY_COUNT
1387 This variable defines the number of retries for
1388 network operations like ARP, RARP, TFTP, or BOOTP
1389 before giving up the operation. If not defined, a
1390 default value of 5 is used.
1392 - Command Interpreter:
1395 Enable auto completion of commands using TAB.
1399 Define this variable to enable the "hush" shell (from
1400 Busybox) as command line interpreter, thus enabling
1401 powerful command line syntax like
1402 if...then...else...fi conditionals or `&&' and '||'
1403 constructs ("shell scripts").
1405 If undefined, you get the old, much simpler behaviour
1406 with a somewhat smaller memory footprint.
1411 This defines the secondary prompt string, which is
1412 printed when the command interpreter needs more input
1413 to complete a command. Usually "> ".
1417 In the current implementation, the local variables
1418 space and global environment variables space are
1419 separated. Local variables are those you define by
1420 simply typing `name=value'. To access a local
1421 variable later on, you have write `$name' or
1422 `${name}'; to execute the contents of a variable
1423 directly type `$name' at the command prompt.
1425 Global environment variables are those you use
1426 setenv/printenv to work with. To run a command stored
1427 in such a variable, you need to use the run command,
1428 and you must not use the '$' sign to access them.
1430 To store commands and special characters in a
1431 variable, please use double quotation marks
1432 surrounding the whole text of the variable, instead
1433 of the backslashes before semicolons and special
1436 - Default Environment:
1437 CONFIG_EXTRA_ENV_SETTINGS
1439 Define this to contain any number of null terminated
1440 strings (variable = value pairs) that will be part of
1441 the default environment compiled into the boot image.
1443 For example, place something like this in your
1444 board's config file:
1446 #define CONFIG_EXTRA_ENV_SETTINGS \
1450 Warning: This method is based on knowledge about the
1451 internal format how the environment is stored by the
1452 U-Boot code. This is NOT an official, exported
1453 interface! Although it is unlikely that this format
1454 will change soon, there is no guarantee either.
1455 You better know what you are doing here.
1457 Note: overly (ab)use of the default environment is
1458 discouraged. Make sure to check other ways to preset
1459 the environment like the autoscript function or the
1462 - DataFlash Support:
1463 CONFIG_HAS_DATAFLASH
1465 Defining this option enables DataFlash features and
1466 allows to read/write in Dataflash via the standard
1469 - SystemACE Support:
1472 Adding this option adds support for Xilinx SystemACE
1473 chips attached via some sort of local bus. The address
1474 of the chip must alsh be defined in the
1475 CFG_SYSTEMACE_BASE macro. For example:
1477 #define CONFIG_SYSTEMACE
1478 #define CFG_SYSTEMACE_BASE 0xf0000000
1480 When SystemACE support is added, the "ace" device type
1481 becomes available to the fat commands, i.e. fatls.
1483 - Show boot progress:
1484 CONFIG_SHOW_BOOT_PROGRESS
1486 Defining this option allows to add some board-
1487 specific code (calling a user-provided function
1488 "show_boot_progress(int)") that enables you to show
1489 the system's boot progress on some display (for
1490 example, some LED's) on your board. At the moment,
1491 the following checkpoints are implemented:
1494 1 common/cmd_bootm.c before attempting to boot an image
1495 -1 common/cmd_bootm.c Image header has bad magic number
1496 2 common/cmd_bootm.c Image header has correct magic number
1497 -2 common/cmd_bootm.c Image header has bad checksum
1498 3 common/cmd_bootm.c Image header has correct checksum
1499 -3 common/cmd_bootm.c Image data has bad checksum
1500 4 common/cmd_bootm.c Image data has correct checksum
1501 -4 common/cmd_bootm.c Image is for unsupported architecture
1502 5 common/cmd_bootm.c Architecture check OK
1503 -5 common/cmd_bootm.c Wrong Image Type (not kernel, multi, standalone)
1504 6 common/cmd_bootm.c Image Type check OK
1505 -6 common/cmd_bootm.c gunzip uncompression error
1506 -7 common/cmd_bootm.c Unimplemented compression type
1507 7 common/cmd_bootm.c Uncompression OK
1508 -8 common/cmd_bootm.c Wrong Image Type (not kernel, multi, standalone)
1509 8 common/cmd_bootm.c Image Type check OK
1510 -9 common/cmd_bootm.c Unsupported OS (not Linux, BSD, VxWorks, QNX)
1511 9 common/cmd_bootm.c Start initial ramdisk verification
1512 -10 common/cmd_bootm.c Ramdisk header has bad magic number
1513 -11 common/cmd_bootm.c Ramdisk header has bad checksum
1514 10 common/cmd_bootm.c Ramdisk header is OK
1515 -12 common/cmd_bootm.c Ramdisk data has bad checksum
1516 11 common/cmd_bootm.c Ramdisk data has correct checksum
1517 12 common/cmd_bootm.c Ramdisk verification complete, start loading
1518 -13 common/cmd_bootm.c Wrong Image Type (not PPC Linux Ramdisk)
1519 13 common/cmd_bootm.c Start multifile image verification
1520 14 common/cmd_bootm.c No initial ramdisk, no multifile, continue.
1521 15 common/cmd_bootm.c All preparation done, transferring control to OS
1523 -30 lib_ppc/board.c Fatal error, hang the system
1524 -31 post/post.c POST test failed, detected by post_output_backlog()
1525 -32 post/post.c POST test failed, detected by post_run_single()
1527 -1 common/cmd_doc.c Bad usage of "doc" command
1528 -1 common/cmd_doc.c No boot device
1529 -1 common/cmd_doc.c Unknown Chip ID on boot device
1530 -1 common/cmd_doc.c Read Error on boot device
1531 -1 common/cmd_doc.c Image header has bad magic number
1533 -1 common/cmd_ide.c Bad usage of "ide" command
1534 -1 common/cmd_ide.c No boot device
1535 -1 common/cmd_ide.c Unknown boot device
1536 -1 common/cmd_ide.c Unknown partition table
1537 -1 common/cmd_ide.c Invalid partition type
1538 -1 common/cmd_ide.c Read Error on boot device
1539 -1 common/cmd_ide.c Image header has bad magic number
1541 -1 common/cmd_nand.c Bad usage of "nand" command
1542 -1 common/cmd_nand.c No boot device
1543 -1 common/cmd_nand.c Unknown Chip ID on boot device
1544 -1 common/cmd_nand.c Read Error on boot device
1545 -1 common/cmd_nand.c Image header has bad magic number
1547 -1 common/env_common.c Environment has a bad CRC, using default
1553 [so far only for SMDK2400 and TRAB boards]
1555 - Modem support endable:
1556 CONFIG_MODEM_SUPPORT
1558 - RTS/CTS Flow control enable:
1561 - Modem debug support:
1562 CONFIG_MODEM_SUPPORT_DEBUG
1564 Enables debugging stuff (char screen[1024], dbg())
1565 for modem support. Useful only with BDI2000.
1567 - Interrupt support (PPC):
1569 There are common interrupt_init() and timer_interrupt()
1570 for all PPC archs. interrupt_init() calls interrupt_init_cpu()
1571 for cpu specific initialization. interrupt_init_cpu()
1572 should set decrementer_count to appropriate value. If
1573 cpu resets decrementer automatically after interrupt
1574 (ppc4xx) it should set decrementer_count to zero.
1575 timer_interrupt() calls timer_interrupt_cpu() for cpu
1576 specific handling. If board has watchdog / status_led
1577 / other_activity_monitor it works automatically from
1578 general timer_interrupt().
1582 In the target system modem support is enabled when a
1583 specific key (key combination) is pressed during
1584 power-on. Otherwise U-Boot will boot normally
1585 (autoboot). The key_pressed() fuction is called from
1586 board_init(). Currently key_pressed() is a dummy
1587 function, returning 1 and thus enabling modem
1590 If there are no modem init strings in the
1591 environment, U-Boot proceed to autoboot; the
1592 previous output (banner, info printfs) will be
1595 See also: doc/README.Modem
1598 Configuration Settings:
1599 -----------------------
1601 - CFG_LONGHELP: Defined when you want long help messages included;
1602 undefine this when you're short of memory.
1604 - CFG_PROMPT: This is what U-Boot prints on the console to
1605 prompt for user input.
1607 - CFG_CBSIZE: Buffer size for input from the Console
1609 - CFG_PBSIZE: Buffer size for Console output
1611 - CFG_MAXARGS: max. Number of arguments accepted for monitor commands
1613 - CFG_BARGSIZE: Buffer size for Boot Arguments which are passed to
1614 the application (usually a Linux kernel) when it is
1617 - CFG_BAUDRATE_TABLE:
1618 List of legal baudrate settings for this board.
1620 - CFG_CONSOLE_INFO_QUIET
1621 Suppress display of console information at boot.
1623 - CFG_CONSOLE_IS_IN_ENV
1624 If the board specific function
1625 extern int overwrite_console (void);
1626 returns 1, the stdin, stderr and stdout are switched to the
1627 serial port, else the settings in the environment are used.
1629 - CFG_CONSOLE_OVERWRITE_ROUTINE
1630 Enable the call to overwrite_console().
1632 - CFG_CONSOLE_ENV_OVERWRITE
1633 Enable overwrite of previous console environment settings.
1635 - CFG_MEMTEST_START, CFG_MEMTEST_END:
1636 Begin and End addresses of the area used by the
1640 Enable an alternate, more extensive memory test.
1642 - CFG_MEMTEST_SCRATCH:
1643 Scratch address used by the alternate memory test
1644 You only need to set this if address zero isn't writeable
1646 - CFG_TFTP_LOADADDR:
1647 Default load address for network file downloads
1649 - CFG_LOADS_BAUD_CHANGE:
1650 Enable temporary baudrate change while serial download
1653 Physical start address of SDRAM. _Must_ be 0 here.
1656 Physical start address of Motherboard I/O (if using a
1660 Physical start address of Flash memory.
1663 Physical start address of boot monitor code (set by
1664 make config files to be same as the text base address
1665 (TEXT_BASE) used when linking) - same as
1666 CFG_FLASH_BASE when booting from flash.
1669 Size of memory reserved for monitor code, used to
1670 determine _at_compile_time_ (!) if the environment is
1671 embedded within the U-Boot image, or in a separate
1675 Size of DRAM reserved for malloc() use.
1678 Maximum size of memory mapped by the startup code of
1679 the Linux kernel; all data that must be processed by
1680 the Linux kernel (bd_info, boot arguments, eventually
1681 initrd image) must be put below this limit.
1683 - CFG_MAX_FLASH_BANKS:
1684 Max number of Flash memory banks
1686 - CFG_MAX_FLASH_SECT:
1687 Max number of sectors on a Flash chip
1689 - CFG_FLASH_ERASE_TOUT:
1690 Timeout for Flash erase operations (in ms)
1692 - CFG_FLASH_WRITE_TOUT:
1693 Timeout for Flash write operations (in ms)
1695 - CFG_FLASH_LOCK_TOUT
1696 Timeout for Flash set sector lock bit operation (in ms)
1698 - CFG_FLASH_UNLOCK_TOUT
1699 Timeout for Flash clear lock bits operation (in ms)
1701 - CFG_FLASH_PROTECTION
1702 If defined, hardware flash sectors protection is used
1703 instead of U-Boot software protection.
1705 - CFG_DIRECT_FLASH_TFTP:
1707 Enable TFTP transfers directly to flash memory;
1708 without this option such a download has to be
1709 performed in two steps: (1) download to RAM, and (2)
1710 copy from RAM to flash.
1712 The two-step approach is usually more reliable, since
1713 you can check if the download worked before you erase
1714 the flash, but in some situations (when sytem RAM is
1715 too limited to allow for a tempory copy of the
1716 downloaded image) this option may be very useful.
1719 Define if the flash driver uses extra elements in the
1720 common flash structure for storing flash geometry.
1722 - CFG_FLASH_CFI_DRIVER
1723 This option also enables the building of the cfi_flash driver
1724 in the drivers directory
1726 - CFG_RX_ETH_BUFFER:
1727 Defines the number of ethernet receive buffers. On some
1728 ethernet controllers it is recommended to set this value
1729 to 8 or even higher (EEPRO100 or 405 EMAC), since all
1730 buffers can be full shortly after enabling the interface
1731 on high ethernet traffic.
1732 Defaults to 4 if not defined.
1734 The following definitions that deal with the placement and management
1735 of environment data (variable area); in general, we support the
1736 following configurations:
1738 - CFG_ENV_IS_IN_FLASH:
1740 Define this if the environment is in flash memory.
1742 a) The environment occupies one whole flash sector, which is
1743 "embedded" in the text segment with the U-Boot code. This
1744 happens usually with "bottom boot sector" or "top boot
1745 sector" type flash chips, which have several smaller
1746 sectors at the start or the end. For instance, such a
1747 layout can have sector sizes of 8, 2x4, 16, Nx32 kB. In
1748 such a case you would place the environment in one of the
1749 4 kB sectors - with U-Boot code before and after it. With
1750 "top boot sector" type flash chips, you would put the
1751 environment in one of the last sectors, leaving a gap
1752 between U-Boot and the environment.
1756 Offset of environment data (variable area) to the
1757 beginning of flash memory; for instance, with bottom boot
1758 type flash chips the second sector can be used: the offset
1759 for this sector is given here.
1761 CFG_ENV_OFFSET is used relative to CFG_FLASH_BASE.
1765 This is just another way to specify the start address of
1766 the flash sector containing the environment (instead of
1769 - CFG_ENV_SECT_SIZE:
1771 Size of the sector containing the environment.
1774 b) Sometimes flash chips have few, equal sized, BIG sectors.
1775 In such a case you don't want to spend a whole sector for
1780 If you use this in combination with CFG_ENV_IS_IN_FLASH
1781 and CFG_ENV_SECT_SIZE, you can specify to use only a part
1782 of this flash sector for the environment. This saves
1783 memory for the RAM copy of the environment.
1785 It may also save flash memory if you decide to use this
1786 when your environment is "embedded" within U-Boot code,
1787 since then the remainder of the flash sector could be used
1788 for U-Boot code. It should be pointed out that this is
1789 STRONGLY DISCOURAGED from a robustness point of view:
1790 updating the environment in flash makes it always
1791 necessary to erase the WHOLE sector. If something goes
1792 wrong before the contents has been restored from a copy in
1793 RAM, your target system will be dead.
1795 - CFG_ENV_ADDR_REDUND
1798 These settings describe a second storage area used to hold
1799 a redundand copy of the environment data, so that there is
1800 a valid backup copy in case there is a power failure during
1801 a "saveenv" operation.
1803 BE CAREFUL! Any changes to the flash layout, and some changes to the
1804 source code will make it necessary to adapt <board>/u-boot.lds*
1808 - CFG_ENV_IS_IN_NVRAM:
1810 Define this if you have some non-volatile memory device
1811 (NVRAM, battery buffered SRAM) which you want to use for the
1817 These two #defines are used to determin the memory area you
1818 want to use for environment. It is assumed that this memory
1819 can just be read and written to, without any special
1822 BE CAREFUL! The first access to the environment happens quite early
1823 in U-Boot initalization (when we try to get the setting of for the
1824 console baudrate). You *MUST* have mappend your NVRAM area then, or
1827 Please note that even with NVRAM we still use a copy of the
1828 environment in RAM: we could work on NVRAM directly, but we want to
1829 keep settings there always unmodified except somebody uses "saveenv"
1830 to save the current settings.
1833 - CFG_ENV_IS_IN_EEPROM:
1835 Use this if you have an EEPROM or similar serial access
1836 device and a driver for it.
1841 These two #defines specify the offset and size of the
1842 environment area within the total memory of your EEPROM.
1844 - CFG_I2C_EEPROM_ADDR:
1845 If defined, specified the chip address of the EEPROM device.
1846 The default address is zero.
1848 - CFG_EEPROM_PAGE_WRITE_BITS:
1849 If defined, the number of bits used to address bytes in a
1850 single page in the EEPROM device. A 64 byte page, for example
1851 would require six bits.
1853 - CFG_EEPROM_PAGE_WRITE_DELAY_MS:
1854 If defined, the number of milliseconds to delay between
1855 page writes. The default is zero milliseconds.
1857 - CFG_I2C_EEPROM_ADDR_LEN:
1858 The length in bytes of the EEPROM memory array address. Note
1859 that this is NOT the chip address length!
1861 - CFG_I2C_EEPROM_ADDR_OVERFLOW:
1862 EEPROM chips that implement "address overflow" are ones
1863 like Catalyst 24WC04/08/16 which has 9/10/11 bits of
1864 address and the extra bits end up in the "chip address" bit
1865 slots. This makes a 24WC08 (1Kbyte) chip look like four 256
1868 Note that we consider the length of the address field to
1869 still be one byte because the extra address bits are hidden
1870 in the chip address.
1873 The size in bytes of the EEPROM device.
1876 - CFG_ENV_IS_IN_DATAFLASH:
1878 Define this if you have a DataFlash memory device which you
1879 want to use for the environment.
1885 These three #defines specify the offset and size of the
1886 environment area within the total memory of your DataFlash placed
1887 at the specified address.
1889 - CFG_ENV_IS_IN_NAND:
1891 Define this if you have a NAND device which you want to use
1892 for the environment.
1897 These two #defines specify the offset and size of the environment
1898 area within the first NAND device.
1900 - CFG_SPI_INIT_OFFSET
1902 Defines offset to the initial SPI buffer area in DPRAM. The
1903 area is used at an early stage (ROM part) if the environment
1904 is configured to reside in the SPI EEPROM: We need a 520 byte
1905 scratch DPRAM area. It is used between the two initialization
1906 calls (spi_init_f() and spi_init_r()). A value of 0xB00 seems
1907 to be a good choice since it makes it far enough from the
1908 start of the data area as well as from the stack pointer.
1910 Please note that the environment is read-only as long as the monitor
1911 has been relocated to RAM and a RAM copy of the environment has been
1912 created; also, when using EEPROM you will have to use getenv_r()
1913 until then to read environment variables.
1915 The environment is protected by a CRC32 checksum. Before the monitor
1916 is relocated into RAM, as a result of a bad CRC you will be working
1917 with the compiled-in default environment - *silently*!!! [This is
1918 necessary, because the first environment variable we need is the
1919 "baudrate" setting for the console - if we have a bad CRC, we don't
1920 have any device yet where we could complain.]
1922 Note: once the monitor has been relocated, then it will complain if
1923 the default environment is used; a new CRC is computed as soon as you
1924 use the "saveenv" command to store a valid environment.
1926 - CFG_FAULT_ECHO_LINK_DOWN:
1927 Echo the inverted Ethernet link state to the fault LED.
1929 Note: If this option is active, then CFG_FAULT_MII_ADDR
1930 also needs to be defined.
1932 - CFG_FAULT_MII_ADDR:
1933 MII address of the PHY to check for the Ethernet link state.
1935 - CFG_64BIT_VSPRINTF:
1936 Makes vsprintf (and all *printf functions) support printing
1937 of 64bit values by using the L quantifier
1939 - CFG_64BIT_STRTOUL:
1940 Adds simple_strtoull that returns a 64bit value
1942 Low Level (hardware related) configuration options:
1943 ---------------------------------------------------
1945 - CFG_CACHELINE_SIZE:
1946 Cache Line Size of the CPU.
1949 Default address of the IMMR after system reset.
1951 Needed on some 8260 systems (MPC8260ADS, PQ2FADS-ZU,
1952 and RPXsuper) to be able to adjust the position of
1953 the IMMR register after a reset.
1955 - Floppy Disk Support:
1956 CFG_FDC_DRIVE_NUMBER
1958 the default drive number (default value 0)
1962 defines the spacing between fdc chipset registers
1967 defines the offset of register from address. It
1968 depends on which part of the data bus is connected to
1969 the fdc chipset. (default value 0)
1971 If CFG_ISA_IO_STRIDE CFG_ISA_IO_OFFSET and
1972 CFG_FDC_DRIVE_NUMBER are undefined, they take their
1975 if CFG_FDC_HW_INIT is defined, then the function
1976 fdc_hw_init() is called at the beginning of the FDC
1977 setup. fdc_hw_init() must be provided by the board
1978 source code. It is used to make hardware dependant
1981 - CFG_IMMR: Physical address of the Internal Memory.
1982 DO NOT CHANGE unless you know exactly what you're
1983 doing! (11-4) [MPC8xx/82xx systems only]
1985 - CFG_INIT_RAM_ADDR:
1987 Start address of memory area that can be used for
1988 initial data and stack; please note that this must be
1989 writable memory that is working WITHOUT special
1990 initialization, i. e. you CANNOT use normal RAM which
1991 will become available only after programming the
1992 memory controller and running certain initialization
1995 U-Boot uses the following memory types:
1996 - MPC8xx and MPC8260: IMMR (internal memory of the CPU)
1997 - MPC824X: data cache
1998 - PPC4xx: data cache
2000 - CFG_GBL_DATA_OFFSET:
2002 Offset of the initial data structure in the memory
2003 area defined by CFG_INIT_RAM_ADDR. Usually
2004 CFG_GBL_DATA_OFFSET is chosen such that the initial
2005 data is located at the end of the available space
2006 (sometimes written as (CFG_INIT_RAM_END -
2007 CFG_INIT_DATA_SIZE), and the initial stack is just
2008 below that area (growing from (CFG_INIT_RAM_ADDR +
2009 CFG_GBL_DATA_OFFSET) downward.
2012 On the MPC824X (or other systems that use the data
2013 cache for initial memory) the address chosen for
2014 CFG_INIT_RAM_ADDR is basically arbitrary - it must
2015 point to an otherwise UNUSED address space between
2016 the top of RAM and the start of the PCI space.
2018 - CFG_SIUMCR: SIU Module Configuration (11-6)
2020 - CFG_SYPCR: System Protection Control (11-9)
2022 - CFG_TBSCR: Time Base Status and Control (11-26)
2024 - CFG_PISCR: Periodic Interrupt Status and Control (11-31)
2026 - CFG_PLPRCR: PLL, Low-Power, and Reset Control Register (15-30)
2028 - CFG_SCCR: System Clock and reset Control Register (15-27)
2030 - CFG_OR_TIMING_SDRAM:
2034 periodic timer for refresh
2036 - CFG_DER: Debug Event Register (37-47)
2038 - FLASH_BASE0_PRELIM, FLASH_BASE1_PRELIM, CFG_REMAP_OR_AM,
2039 CFG_PRELIM_OR_AM, CFG_OR_TIMING_FLASH, CFG_OR0_REMAP,
2040 CFG_OR0_PRELIM, CFG_BR0_PRELIM, CFG_OR1_REMAP, CFG_OR1_PRELIM,
2042 Memory Controller Definitions: BR0/1 and OR0/1 (FLASH)
2044 - SDRAM_BASE2_PRELIM, SDRAM_BASE3_PRELIM, SDRAM_MAX_SIZE,
2045 CFG_OR_TIMING_SDRAM, CFG_OR2_PRELIM, CFG_BR2_PRELIM,
2046 CFG_OR3_PRELIM, CFG_BR3_PRELIM:
2047 Memory Controller Definitions: BR2/3 and OR2/3 (SDRAM)
2049 - CFG_MAMR_PTA, CFG_MPTPR_2BK_4K, CFG_MPTPR_1BK_4K, CFG_MPTPR_2BK_8K,
2050 CFG_MPTPR_1BK_8K, CFG_MAMR_8COL, CFG_MAMR_9COL:
2051 Machine Mode Register and Memory Periodic Timer
2052 Prescaler definitions (SDRAM timing)
2054 - CFG_I2C_UCODE_PATCH, CFG_I2C_DPMEM_OFFSET [0x1FC0]:
2055 enable I2C microcode relocation patch (MPC8xx);
2056 define relocation offset in DPRAM [DSP2]
2058 - CFG_SPI_UCODE_PATCH, CFG_SPI_DPMEM_OFFSET [0x1FC0]:
2059 enable SPI microcode relocation patch (MPC8xx);
2060 define relocation offset in DPRAM [SCC4]
2063 Use OSCM clock mode on MBX8xx board. Be careful,
2064 wrong setting might damage your board. Read
2065 doc/README.MBX before setting this variable!
2067 - CFG_CPM_POST_WORD_ADDR: (MPC8xx, MPC8260 only)
2068 Offset of the bootmode word in DPRAM used by post
2069 (Power On Self Tests). This definition overrides
2070 #define'd default value in commproc.h resp.
2073 - CFG_PCI_SLV_MEM_LOCAL, CFG_PCI_SLV_MEM_BUS, CFG_PICMR0_MASK_ATTRIB,
2074 CFG_PCI_MSTR0_LOCAL, CFG_PCIMSK0_MASK, CFG_PCI_MSTR1_LOCAL,
2075 CFG_PCIMSK1_MASK, CFG_PCI_MSTR_MEM_LOCAL, CFG_PCI_MSTR_MEM_BUS,
2076 CFG_CPU_PCI_MEM_START, CFG_PCI_MSTR_MEM_SIZE, CFG_POCMR0_MASK_ATTRIB,
2077 CFG_PCI_MSTR_MEMIO_LOCAL, CFG_PCI_MSTR_MEMIO_BUS, CPU_PCI_MEMIO_START,
2078 CFG_PCI_MSTR_MEMIO_SIZE, CFG_POCMR1_MASK_ATTRIB, CFG_PCI_MSTR_IO_LOCAL,
2079 CFG_PCI_MSTR_IO_BUS, CFG_CPU_PCI_IO_START, CFG_PCI_MSTR_IO_SIZE,
2080 CFG_POCMR2_MASK_ATTRIB: (MPC826x only)
2081 Overrides the default PCI memory map in cpu/mpc8260/pci.c if set.
2083 - CONFIG_ETHER_ON_FEC[12]
2084 Define to enable FEC[12] on a 8xx series processor.
2086 - CONFIG_FEC[12]_PHY
2087 Define to the hardcoded PHY address which corresponds
2088 to the given FEC; i. e.
2089 #define CONFIG_FEC1_PHY 4
2090 means that the PHY with address 4 is connected to FEC1
2092 When set to -1, means to probe for first available.
2094 - CONFIG_FEC[12]_PHY_NORXERR
2095 The PHY does not have a RXERR line (RMII only).
2096 (so program the FEC to ignore it).
2099 Enable RMII mode for all FECs.
2100 Note that this is a global option, we can't
2101 have one FEC in standard MII mode and another in RMII mode.
2103 - CONFIG_CRC32_VERIFY
2104 Add a verify option to the crc32 command.
2107 => crc32 -v <address> <count> <crc32>
2109 Where address/count indicate a memory area
2110 and crc32 is the correct crc32 which the
2114 Add the "loopw" memory command. This only takes effect if
2115 the memory commands are activated globally (CFG_CMD_MEM).
2118 Add the "mdc" and "mwc" memory commands. These are cyclic
2123 This command will print 4 bytes (10,11,12,13) each 500 ms.
2125 => mwc.l 100 12345678 10
2126 This command will write 12345678 to address 100 all 10 ms.
2128 This only takes effect if the memory commands are activated
2129 globally (CFG_CMD_MEM).
2131 - CONFIG_INIT_CRITICAL
2132 [ARM only] If this variable is NOT defined, then
2133 certain critical initializations (like setting up the
2134 memory controller) are omitted. Normally this
2135 variable MUST be defined for all boards. The only
2136 exception is when U-Boot is loaded (to RAM) by some
2137 other boot loader or by a debugger which performs
2138 these intializations itself.
2140 Building the Software:
2141 ======================
2143 Building U-Boot has been tested in native PPC environments (on a
2144 PowerBook G3 running LinuxPPC 2000) and in cross environments
2145 (running RedHat 6.x and 7.x Linux on x86, Solaris 2.6 on a SPARC, and
2148 If you are not using a native PPC environment, it is assumed that you
2149 have the GNU cross compiling tools available in your path and named
2150 with a prefix of "powerpc-linux-". If this is not the case, (e.g. if
2151 you are using Monta Vista's Hard Hat Linux CDK 1.2) you must change
2152 the definition of CROSS_COMPILE in Makefile. For HHL on a 4xx CPU,
2155 CROSS_COMPILE = ppc_4xx-
2158 U-Boot is intended to be simple to build. After installing the
2159 sources you must configure U-Boot for one specific board type. This
2164 where "NAME_config" is the name of one of the existing
2165 configurations; the following names are supported:
2167 ADCIOP_config FPS860L_config omap730p2_config
2168 ADS860_config GEN860T_config pcu_e_config
2170 AR405_config GENIETV_config PIP405_config
2171 at91rm9200dk_config GTH_config QS823_config
2172 CANBT_config hermes_config QS850_config
2173 cmi_mpc5xx_config hymod_config QS860T_config
2174 cogent_common_config IP860_config RPXlite_config
2175 cogent_mpc8260_config IVML24_config RPXlite_DW_config
2176 cogent_mpc8xx_config IVMS8_config RPXsuper_config
2177 CPCI405_config JSE_config rsdproto_config
2178 CPCIISER4_config LANTEC_config Sandpoint8240_config
2179 csb272_config lwmon_config sbc8260_config
2180 CU824_config MBX860T_config sbc8560_33_config
2181 DUET_ADS_config MBX_config sbc8560_66_config
2182 EBONY_config MPC8260ADS_config SM850_config
2183 ELPT860_config MPC8540ADS_config SPD823TS_config
2184 ESTEEM192E_config MPC8560ADS_config stxgp3_config
2185 ETX094_config NETVIA_config SXNI855T_config
2186 FADS823_config omap1510inn_config TQM823L_config
2187 FADS850SAR_config omap1610h2_config TQM850L_config
2188 FADS860T_config omap1610inn_config TQM855L_config
2189 FPS850L_config omap5912osk_config TQM860L_config
2190 omap2420h4_config WALNUT405_config
2194 Note: for some board special configuration names may exist; check if
2195 additional information is available from the board vendor; for
2196 instance, the TQM823L systems are available without (standard)
2197 or with LCD support. You can select such additional "features"
2198 when chosing the configuration, i. e.
2201 - will configure for a plain TQM823L, i. e. no LCD support
2203 make TQM823L_LCD_config
2204 - will configure for a TQM823L with U-Boot console on LCD
2209 Finally, type "make all", and you should get some working U-Boot
2210 images ready for download to / installation on your system:
2212 - "u-boot.bin" is a raw binary image
2213 - "u-boot" is an image in ELF binary format
2214 - "u-boot.srec" is in Motorola S-Record format
2217 Please be aware that the Makefiles assume you are using GNU make, so
2218 for instance on NetBSD you might need to use "gmake" instead of
2222 If the system board that you have is not listed, then you will need
2223 to port U-Boot to your hardware platform. To do this, follow these
2226 1. Add a new configuration option for your board to the toplevel
2227 "Makefile" and to the "MAKEALL" script, using the existing
2228 entries as examples. Note that here and at many other places
2229 boards and other names are listed in alphabetical sort order. Please
2231 2. Create a new directory to hold your board specific code. Add any
2232 files you need. In your board directory, you will need at least
2233 the "Makefile", a "<board>.c", "flash.c" and "u-boot.lds".
2234 3. Create a new configuration file "include/configs/<board>.h" for
2236 3. If you're porting U-Boot to a new CPU, then also create a new
2237 directory to hold your CPU specific code. Add any files you need.
2238 4. Run "make <board>_config" with your new name.
2239 5. Type "make", and you should get a working "u-boot.srec" file
2240 to be installed on your target system.
2241 6. Debug and solve any problems that might arise.
2242 [Of course, this last step is much harder than it sounds.]
2245 Testing of U-Boot Modifications, Ports to New Hardware, etc.:
2246 ==============================================================
2248 If you have modified U-Boot sources (for instance added a new board
2249 or support for new devices, a new CPU, etc.) you are expected to
2250 provide feedback to the other developers. The feedback normally takes
2251 the form of a "patch", i. e. a context diff against a certain (latest
2252 official or latest in CVS) version of U-Boot sources.
2254 But before you submit such a patch, please verify that your modifi-
2255 cation did not break existing code. At least make sure that *ALL* of
2256 the supported boards compile WITHOUT ANY compiler warnings. To do so,
2257 just run the "MAKEALL" script, which will configure and build U-Boot
2258 for ALL supported system. Be warned, this will take a while. You can
2259 select which (cross) compiler to use by passing a `CROSS_COMPILE'
2260 environment variable to the script, i. e. to use the cross tools from
2261 MontaVista's Hard Hat Linux you can type
2263 CROSS_COMPILE=ppc_8xx- MAKEALL
2265 or to build on a native PowerPC system you can type
2267 CROSS_COMPILE=' ' MAKEALL
2269 See also "U-Boot Porting Guide" below.
2272 Monitor Commands - Overview:
2273 ============================
2275 go - start application at address 'addr'
2276 run - run commands in an environment variable
2277 bootm - boot application image from memory
2278 bootp - boot image via network using BootP/TFTP protocol
2279 tftpboot- boot image via network using TFTP protocol
2280 and env variables "ipaddr" and "serverip"
2281 (and eventually "gatewayip")
2282 rarpboot- boot image via network using RARP/TFTP protocol
2283 diskboot- boot from IDE devicebootd - boot default, i.e., run 'bootcmd'
2284 loads - load S-Record file over serial line
2285 loadb - load binary file over serial line (kermit mode)
2287 mm - memory modify (auto-incrementing)
2288 nm - memory modify (constant address)
2289 mw - memory write (fill)
2291 cmp - memory compare
2292 crc32 - checksum calculation
2293 imd - i2c memory display
2294 imm - i2c memory modify (auto-incrementing)
2295 inm - i2c memory modify (constant address)
2296 imw - i2c memory write (fill)
2297 icrc32 - i2c checksum calculation
2298 iprobe - probe to discover valid I2C chip addresses
2299 iloop - infinite loop on address range
2300 isdram - print SDRAM configuration information
2301 sspi - SPI utility commands
2302 base - print or set address offset
2303 printenv- print environment variables
2304 setenv - set environment variables
2305 saveenv - save environment variables to persistent storage
2306 protect - enable or disable FLASH write protection
2307 erase - erase FLASH memory
2308 flinfo - print FLASH memory information
2309 bdinfo - print Board Info structure
2310 iminfo - print header information for application image
2311 coninfo - print console devices and informations
2312 ide - IDE sub-system
2313 loop - infinite loop on address range
2314 loopw - infinite write loop on address range
2315 mtest - simple RAM test
2316 icache - enable or disable instruction cache
2317 dcache - enable or disable data cache
2318 reset - Perform RESET of the CPU
2319 echo - echo args to console
2320 version - print monitor version
2321 help - print online help
2322 ? - alias for 'help'
2325 Monitor Commands - Detailed Description:
2326 ========================================
2330 For now: just type "help <command>".
2333 Environment Variables:
2334 ======================
2336 U-Boot supports user configuration using Environment Variables which
2337 can be made persistent by saving to Flash memory.
2339 Environment Variables are set using "setenv", printed using
2340 "printenv", and saved to Flash using "saveenv". Using "setenv"
2341 without a value can be used to delete a variable from the
2342 environment. As long as you don't save the environment you are
2343 working with an in-memory copy. In case the Flash area containing the
2344 environment is erased by accident, a default environment is provided.
2346 Some configuration options can be set using Environment Variables:
2348 baudrate - see CONFIG_BAUDRATE
2350 bootdelay - see CONFIG_BOOTDELAY
2352 bootcmd - see CONFIG_BOOTCOMMAND
2354 bootargs - Boot arguments when booting an RTOS image
2356 bootfile - Name of the image to load with TFTP
2358 autoload - if set to "no" (any string beginning with 'n'),
2359 "bootp" will just load perform a lookup of the
2360 configuration from the BOOTP server, but not try to
2361 load any image using TFTP
2363 autostart - if set to "yes", an image loaded using the "bootp",
2364 "rarpboot", "tftpboot" or "diskboot" commands will
2365 be automatically started (by internally calling
2368 If set to "no", a standalone image passed to the
2369 "bootm" command will be copied to the load address
2370 (and eventually uncompressed), but NOT be started.
2371 This can be used to load and uncompress arbitrary
2374 i2cfast - (PPC405GP|PPC405EP only)
2375 if set to 'y' configures Linux I2C driver for fast
2376 mode (400kHZ). This environment variable is used in
2377 initialization code. So, for changes to be effective
2378 it must be saved and board must be reset.
2380 initrd_high - restrict positioning of initrd images:
2381 If this variable is not set, initrd images will be
2382 copied to the highest possible address in RAM; this
2383 is usually what you want since it allows for
2384 maximum initrd size. If for some reason you want to
2385 make sure that the initrd image is loaded below the
2386 CFG_BOOTMAPSZ limit, you can set this environment
2387 variable to a value of "no" or "off" or "0".
2388 Alternatively, you can set it to a maximum upper
2389 address to use (U-Boot will still check that it
2390 does not overwrite the U-Boot stack and data).
2392 For instance, when you have a system with 16 MB
2393 RAM, and want to reserve 4 MB from use by Linux,
2394 you can do this by adding "mem=12M" to the value of
2395 the "bootargs" variable. However, now you must make
2396 sure that the initrd image is placed in the first
2397 12 MB as well - this can be done with
2399 setenv initrd_high 00c00000
2401 If you set initrd_high to 0xFFFFFFFF, this is an
2402 indication to U-Boot that all addresses are legal
2403 for the Linux kernel, including addresses in flash
2404 memory. In this case U-Boot will NOT COPY the
2405 ramdisk at all. This may be useful to reduce the
2406 boot time on your system, but requires that this
2407 feature is supported by your Linux kernel.
2409 ipaddr - IP address; needed for tftpboot command
2411 loadaddr - Default load address for commands like "bootp",
2412 "rarpboot", "tftpboot", "loadb" or "diskboot"
2414 loads_echo - see CONFIG_LOADS_ECHO
2416 serverip - TFTP server IP address; needed for tftpboot command
2418 bootretry - see CONFIG_BOOT_RETRY_TIME
2420 bootdelaykey - see CONFIG_AUTOBOOT_DELAY_STR
2422 bootstopkey - see CONFIG_AUTOBOOT_STOP_STR
2424 ethprime - When CONFIG_NET_MULTI is enabled controls which
2425 interface is used first.
2427 ethact - When CONFIG_NET_MULTI is enabled controls which
2428 interface is currently active. For example you
2429 can do the following
2431 => setenv ethact FEC ETHERNET
2432 => ping 192.168.0.1 # traffic sent on FEC ETHERNET
2433 => setenv ethact SCC ETHERNET
2434 => ping 10.0.0.1 # traffic sent on SCC ETHERNET
2436 netretry - When set to "no" each network operation will
2437 either succeed or fail without retrying.
2438 When set to "once" the network operation will
2439 fail when all the available network interfaces
2440 are tried once without success.
2441 Useful on scripts which control the retry operation
2444 vlan - When set to a value < 4095 the traffic over
2445 ethernet is encapsulated/received over 802.1q
2448 The following environment variables may be used and automatically
2449 updated by the network boot commands ("bootp" and "rarpboot"),
2450 depending the information provided by your boot server:
2452 bootfile - see above
2453 dnsip - IP address of your Domain Name Server
2454 dnsip2 - IP address of your secondary Domain Name Server
2455 gatewayip - IP address of the Gateway (Router) to use
2456 hostname - Target hostname
2458 netmask - Subnet Mask
2459 rootpath - Pathname of the root filesystem on the NFS server
2460 serverip - see above
2463 There are two special Environment Variables:
2465 serial# - contains hardware identification information such
2466 as type string and/or serial number
2467 ethaddr - Ethernet address
2469 These variables can be set only once (usually during manufacturing of
2470 the board). U-Boot refuses to delete or overwrite these variables
2471 once they have been set once.
2474 Further special Environment Variables:
2476 ver - Contains the U-Boot version string as printed
2477 with the "version" command. This variable is
2478 readonly (see CONFIG_VERSION_VARIABLE).
2481 Please note that changes to some configuration parameters may take
2482 only effect after the next boot (yes, that's just like Windoze :-).
2485 Command Line Parsing:
2486 =====================
2488 There are two different command line parsers available with U-Boot:
2489 the old "simple" one, and the much more powerful "hush" shell:
2491 Old, simple command line parser:
2492 --------------------------------
2494 - supports environment variables (through setenv / saveenv commands)
2495 - several commands on one line, separated by ';'
2496 - variable substitution using "... $(name) ..." syntax
2497 - special characters ('$', ';') can be escaped by prefixing with '\',
2499 setenv bootcmd bootm \$(address)
2500 - You can also escape text by enclosing in single apostrophes, for example:
2501 setenv addip 'setenv bootargs $bootargs ip=$ipaddr:$serverip:$gatewayip:$netmask:$hostname::off'
2506 - similar to Bourne shell, with control structures like
2507 if...then...else...fi, for...do...done; while...do...done,
2508 until...do...done, ...
2509 - supports environment ("global") variables (through setenv / saveenv
2510 commands) and local shell variables (through standard shell syntax
2511 "name=value"); only environment variables can be used with "run"
2517 (1) If a command line (or an environment variable executed by a "run"
2518 command) contains several commands separated by semicolon, and
2519 one of these commands fails, then the remaining commands will be
2522 (2) If you execute several variables with one call to run (i. e.
2523 calling run with a list af variables as arguments), any failing
2524 command will cause "run" to terminate, i. e. the remaining
2525 variables are not executed.
2527 Note for Redundant Ethernet Interfaces:
2528 =======================================
2530 Some boards come with redundant ethernet interfaces; U-Boot supports
2531 such configurations and is capable of automatic selection of a
2532 "working" interface when needed. MAC assignment works as follows:
2534 Network interfaces are numbered eth0, eth1, eth2, ... Corresponding
2535 MAC addresses can be stored in the environment as "ethaddr" (=>eth0),
2536 "eth1addr" (=>eth1), "eth2addr", ...
2538 If the network interface stores some valid MAC address (for instance
2539 in SROM), this is used as default address if there is NO correspon-
2540 ding setting in the environment; if the corresponding environment
2541 variable is set, this overrides the settings in the card; that means:
2543 o If the SROM has a valid MAC address, and there is no address in the
2544 environment, the SROM's address is used.
2546 o If there is no valid address in the SROM, and a definition in the
2547 environment exists, then the value from the environment variable is
2550 o If both the SROM and the environment contain a MAC address, and
2551 both addresses are the same, this MAC address is used.
2553 o If both the SROM and the environment contain a MAC address, and the
2554 addresses differ, the value from the environment is used and a
2557 o If neither SROM nor the environment contain a MAC address, an error
2564 The "boot" commands of this monitor operate on "image" files which
2565 can be basicly anything, preceeded by a special header; see the
2566 definitions in include/image.h for details; basicly, the header
2567 defines the following image properties:
2569 * Target Operating System (Provisions for OpenBSD, NetBSD, FreeBSD,
2570 4.4BSD, Linux, SVR4, Esix, Solaris, Irix, SCO, Dell, NCR, VxWorks,
2571 LynxOS, pSOS, QNX, RTEMS, ARTOS;
2572 Currently supported: Linux, NetBSD, VxWorks, QNX, RTEMS, ARTOS, LynxOS).
2573 * Target CPU Architecture (Provisions for Alpha, ARM, Intel x86,
2574 IA64, MIPS, NIOS, PowerPC, IBM S390, SuperH, Sparc, Sparc 64 Bit;
2575 Currently supported: ARM, Intel x86, MIPS, NIOS, PowerPC).
2576 * Compression Type (uncompressed, gzip, bzip2)
2582 The header is marked by a special Magic Number, and both the header
2583 and the data portions of the image are secured against corruption by
2590 Although U-Boot should support any OS or standalone application
2591 easily, the main focus has always been on Linux during the design of
2594 U-Boot includes many features that so far have been part of some
2595 special "boot loader" code within the Linux kernel. Also, any
2596 "initrd" images to be used are no longer part of one big Linux image;
2597 instead, kernel and "initrd" are separate images. This implementation
2598 serves several purposes:
2600 - the same features can be used for other OS or standalone
2601 applications (for instance: using compressed images to reduce the
2602 Flash memory footprint)
2604 - it becomes much easier to port new Linux kernel versions because
2605 lots of low-level, hardware dependent stuff are done by U-Boot
2607 - the same Linux kernel image can now be used with different "initrd"
2608 images; of course this also means that different kernel images can
2609 be run with the same "initrd". This makes testing easier (you don't
2610 have to build a new "zImage.initrd" Linux image when you just
2611 change a file in your "initrd"). Also, a field-upgrade of the
2612 software is easier now.
2618 Porting Linux to U-Boot based systems:
2619 ---------------------------------------
2621 U-Boot cannot save you from doing all the necessary modifications to
2622 configure the Linux device drivers for use with your target hardware
2623 (no, we don't intend to provide a full virtual machine interface to
2626 But now you can ignore ALL boot loader code (in arch/ppc/mbxboot).
2628 Just make sure your machine specific header file (for instance
2629 include/asm-ppc/tqm8xx.h) includes the same definition of the Board
2630 Information structure as we define in include/u-boot.h, and make
2631 sure that your definition of IMAP_ADDR uses the same value as your
2632 U-Boot configuration in CFG_IMMR.
2635 Configuring the Linux kernel:
2636 -----------------------------
2638 No specific requirements for U-Boot. Make sure you have some root
2639 device (initial ramdisk, NFS) for your target system.
2642 Building a Linux Image:
2643 -----------------------
2645 With U-Boot, "normal" build targets like "zImage" or "bzImage" are
2646 not used. If you use recent kernel source, a new build target
2647 "uImage" will exist which automatically builds an image usable by
2648 U-Boot. Most older kernels also have support for a "pImage" target,
2649 which was introduced for our predecessor project PPCBoot and uses a
2650 100% compatible format.
2659 The "uImage" build target uses a special tool (in 'tools/mkimage') to
2660 encapsulate a compressed Linux kernel image with header information,
2661 CRC32 checksum etc. for use with U-Boot. This is what we are doing:
2663 * build a standard "vmlinux" kernel image (in ELF binary format):
2665 * convert the kernel into a raw binary image:
2667 ${CROSS_COMPILE}-objcopy -O binary \
2668 -R .note -R .comment \
2669 -S vmlinux linux.bin
2671 * compress the binary image:
2675 * package compressed binary image for U-Boot:
2677 mkimage -A ppc -O linux -T kernel -C gzip \
2678 -a 0 -e 0 -n "Linux Kernel Image" \
2679 -d linux.bin.gz uImage
2682 The "mkimage" tool can also be used to create ramdisk images for use
2683 with U-Boot, either separated from the Linux kernel image, or
2684 combined into one file. "mkimage" encapsulates the images with a 64
2685 byte header containing information about target architecture,
2686 operating system, image type, compression method, entry points, time
2687 stamp, CRC32 checksums, etc.
2689 "mkimage" can be called in two ways: to verify existing images and
2690 print the header information, or to build new images.
2692 In the first form (with "-l" option) mkimage lists the information
2693 contained in the header of an existing U-Boot image; this includes
2694 checksum verification:
2696 tools/mkimage -l image
2697 -l ==> list image header information
2699 The second form (with "-d" option) is used to build a U-Boot image
2700 from a "data file" which is used as image payload:
2702 tools/mkimage -A arch -O os -T type -C comp -a addr -e ep \
2703 -n name -d data_file image
2704 -A ==> set architecture to 'arch'
2705 -O ==> set operating system to 'os'
2706 -T ==> set image type to 'type'
2707 -C ==> set compression type 'comp'
2708 -a ==> set load address to 'addr' (hex)
2709 -e ==> set entry point to 'ep' (hex)
2710 -n ==> set image name to 'name'
2711 -d ==> use image data from 'datafile'
2713 Right now, all Linux kernels for PowerPC systems use the same load
2714 address (0x00000000), but the entry point address depends on the
2717 - 2.2.x kernels have the entry point at 0x0000000C,
2718 - 2.3.x and later kernels have the entry point at 0x00000000.
2720 So a typical call to build a U-Boot image would read:
2722 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \
2723 > -A ppc -O linux -T kernel -C gzip -a 0 -e 0 \
2724 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/ppc/coffboot/vmlinux.gz \
2725 > examples/uImage.TQM850L
2726 Image Name: 2.4.4 kernel for TQM850L
2727 Created: Wed Jul 19 02:34:59 2000
2728 Image Type: PowerPC Linux Kernel Image (gzip compressed)
2729 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB
2730 Load Address: 0x00000000
2731 Entry Point: 0x00000000
2733 To verify the contents of the image (or check for corruption):
2735 -> tools/mkimage -l examples/uImage.TQM850L
2736 Image Name: 2.4.4 kernel for TQM850L
2737 Created: Wed Jul 19 02:34:59 2000
2738 Image Type: PowerPC Linux Kernel Image (gzip compressed)
2739 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB
2740 Load Address: 0x00000000
2741 Entry Point: 0x00000000
2743 NOTE: for embedded systems where boot time is critical you can trade
2744 speed for memory and install an UNCOMPRESSED image instead: this
2745 needs more space in Flash, but boots much faster since it does not
2746 need to be uncompressed:
2748 -> gunzip /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/ppc/coffboot/vmlinux.gz
2749 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \
2750 > -A ppc -O linux -T kernel -C none -a 0 -e 0 \
2751 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/ppc/coffboot/vmlinux \
2752 > examples/uImage.TQM850L-uncompressed
2753 Image Name: 2.4.4 kernel for TQM850L
2754 Created: Wed Jul 19 02:34:59 2000
2755 Image Type: PowerPC Linux Kernel Image (uncompressed)
2756 Data Size: 792160 Bytes = 773.59 kB = 0.76 MB
2757 Load Address: 0x00000000
2758 Entry Point: 0x00000000
2761 Similar you can build U-Boot images from a 'ramdisk.image.gz' file
2762 when your kernel is intended to use an initial ramdisk:
2764 -> tools/mkimage -n 'Simple Ramdisk Image' \
2765 > -A ppc -O linux -T ramdisk -C gzip \
2766 > -d /LinuxPPC/images/SIMPLE-ramdisk.image.gz examples/simple-initrd
2767 Image Name: Simple Ramdisk Image
2768 Created: Wed Jan 12 14:01:50 2000
2769 Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
2770 Data Size: 566530 Bytes = 553.25 kB = 0.54 MB
2771 Load Address: 0x00000000
2772 Entry Point: 0x00000000
2775 Installing a Linux Image:
2776 -------------------------
2778 To downloading a U-Boot image over the serial (console) interface,
2779 you must convert the image to S-Record format:
2781 objcopy -I binary -O srec examples/image examples/image.srec
2783 The 'objcopy' does not understand the information in the U-Boot
2784 image header, so the resulting S-Record file will be relative to
2785 address 0x00000000. To load it to a given address, you need to
2786 specify the target address as 'offset' parameter with the 'loads'
2789 Example: install the image to address 0x40100000 (which on the
2790 TQM8xxL is in the first Flash bank):
2792 => erase 40100000 401FFFFF
2798 ## Ready for S-Record download ...
2799 ~>examples/image.srec
2800 1 2 3 4 5 6 7 8 9 10 11 12 13 ...
2802 15989 15990 15991 15992
2803 [file transfer complete]
2805 ## Start Addr = 0x00000000
2808 You can check the success of the download using the 'iminfo' command;
2809 this includes a checksum verification so you can be sure no data
2810 corruption happened:
2814 ## Checking Image at 40100000 ...
2815 Image Name: 2.2.13 for initrd on TQM850L
2816 Image Type: PowerPC Linux Kernel Image (gzip compressed)
2817 Data Size: 335725 Bytes = 327 kB = 0 MB
2818 Load Address: 00000000
2819 Entry Point: 0000000c
2820 Verifying Checksum ... OK
2826 The "bootm" command is used to boot an application that is stored in
2827 memory (RAM or Flash). In case of a Linux kernel image, the contents
2828 of the "bootargs" environment variable is passed to the kernel as
2829 parameters. You can check and modify this variable using the
2830 "printenv" and "setenv" commands:
2833 => printenv bootargs
2834 bootargs=root=/dev/ram
2836 => setenv bootargs root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
2838 => printenv bootargs
2839 bootargs=root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
2842 ## Booting Linux kernel at 40020000 ...
2843 Image Name: 2.2.13 for NFS on TQM850L
2844 Image Type: PowerPC Linux Kernel Image (gzip compressed)
2845 Data Size: 381681 Bytes = 372 kB = 0 MB
2846 Load Address: 00000000
2847 Entry Point: 0000000c
2848 Verifying Checksum ... OK
2849 Uncompressing Kernel Image ... OK
2850 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
2851 Boot arguments: root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2
2852 time_init: decrementer frequency = 187500000/60
2853 Calibrating delay loop... 49.77 BogoMIPS
2854 Memory: 15208k available (700k kernel code, 444k data, 32k init) [c0000000,c1000000]
2857 If you want to boot a Linux kernel with initial ram disk, you pass
2858 the memory addresses of both the kernel and the initrd image (PPBCOOT
2859 format!) to the "bootm" command:
2861 => imi 40100000 40200000
2863 ## Checking Image at 40100000 ...
2864 Image Name: 2.2.13 for initrd on TQM850L
2865 Image Type: PowerPC Linux Kernel Image (gzip compressed)
2866 Data Size: 335725 Bytes = 327 kB = 0 MB
2867 Load Address: 00000000
2868 Entry Point: 0000000c
2869 Verifying Checksum ... OK
2871 ## Checking Image at 40200000 ...
2872 Image Name: Simple Ramdisk Image
2873 Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
2874 Data Size: 566530 Bytes = 553 kB = 0 MB
2875 Load Address: 00000000
2876 Entry Point: 00000000
2877 Verifying Checksum ... OK
2879 => bootm 40100000 40200000
2880 ## Booting Linux kernel at 40100000 ...
2881 Image Name: 2.2.13 for initrd on TQM850L
2882 Image Type: PowerPC Linux Kernel Image (gzip compressed)
2883 Data Size: 335725 Bytes = 327 kB = 0 MB
2884 Load Address: 00000000
2885 Entry Point: 0000000c
2886 Verifying Checksum ... OK
2887 Uncompressing Kernel Image ... OK
2888 ## Loading RAMDisk Image at 40200000 ...
2889 Image Name: Simple Ramdisk Image
2890 Image Type: PowerPC Linux RAMDisk Image (gzip compressed)
2891 Data Size: 566530 Bytes = 553 kB = 0 MB
2892 Load Address: 00000000
2893 Entry Point: 00000000
2894 Verifying Checksum ... OK
2895 Loading Ramdisk ... OK
2896 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
2897 Boot arguments: root=/dev/ram
2898 time_init: decrementer frequency = 187500000/60
2899 Calibrating delay loop... 49.77 BogoMIPS
2901 RAMDISK: Compressed image found at block 0
2902 VFS: Mounted root (ext2 filesystem).
2906 More About U-Boot Image Types:
2907 ------------------------------
2909 U-Boot supports the following image types:
2911 "Standalone Programs" are directly runnable in the environment
2912 provided by U-Boot; it is expected that (if they behave
2913 well) you can continue to work in U-Boot after return from
2914 the Standalone Program.
2915 "OS Kernel Images" are usually images of some Embedded OS which
2916 will take over control completely. Usually these programs
2917 will install their own set of exception handlers, device
2918 drivers, set up the MMU, etc. - this means, that you cannot
2919 expect to re-enter U-Boot except by resetting the CPU.
2920 "RAMDisk Images" are more or less just data blocks, and their
2921 parameters (address, size) are passed to an OS kernel that is
2923 "Multi-File Images" contain several images, typically an OS
2924 (Linux) kernel image and one or more data images like
2925 RAMDisks. This construct is useful for instance when you want
2926 to boot over the network using BOOTP etc., where the boot
2927 server provides just a single image file, but you want to get
2928 for instance an OS kernel and a RAMDisk image.
2930 "Multi-File Images" start with a list of image sizes, each
2931 image size (in bytes) specified by an "uint32_t" in network
2932 byte order. This list is terminated by an "(uint32_t)0".
2933 Immediately after the terminating 0 follow the images, one by
2934 one, all aligned on "uint32_t" boundaries (size rounded up to
2935 a multiple of 4 bytes).
2937 "Firmware Images" are binary images containing firmware (like
2938 U-Boot or FPGA images) which usually will be programmed to
2941 "Script files" are command sequences that will be executed by
2942 U-Boot's command interpreter; this feature is especially
2943 useful when you configure U-Boot to use a real shell (hush)
2944 as command interpreter.
2950 One of the features of U-Boot is that you can dynamically load and
2951 run "standalone" applications, which can use some resources of
2952 U-Boot like console I/O functions or interrupt services.
2954 Two simple examples are included with the sources:
2959 'examples/hello_world.c' contains a small "Hello World" Demo
2960 application; it is automatically compiled when you build U-Boot.
2961 It's configured to run at address 0x00040004, so you can play with it
2965 ## Ready for S-Record download ...
2966 ~>examples/hello_world.srec
2967 1 2 3 4 5 6 7 8 9 10 11 ...
2968 [file transfer complete]
2970 ## Start Addr = 0x00040004
2972 => go 40004 Hello World! This is a test.
2973 ## Starting application at 0x00040004 ...
2984 Hit any key to exit ...
2986 ## Application terminated, rc = 0x0
2988 Another example, which demonstrates how to register a CPM interrupt
2989 handler with the U-Boot code, can be found in 'examples/timer.c'.
2990 Here, a CPM timer is set up to generate an interrupt every second.
2991 The interrupt service routine is trivial, just printing a '.'
2992 character, but this is just a demo program. The application can be
2993 controlled by the following keys:
2995 ? - print current values og the CPM Timer registers
2996 b - enable interrupts and start timer
2997 e - stop timer and disable interrupts
2998 q - quit application
3001 ## Ready for S-Record download ...
3002 ~>examples/timer.srec
3003 1 2 3 4 5 6 7 8 9 10 11 ...
3004 [file transfer complete]
3006 ## Start Addr = 0x00040004
3009 ## Starting application at 0x00040004 ...
3012 tgcr @ 0xfff00980, tmr @ 0xfff00990, trr @ 0xfff00994, tcr @ 0xfff00998, tcn @ 0xfff0099c, ter @ 0xfff009b0
3015 [q, b, e, ?] Set interval 1000000 us
3018 [q, b, e, ?] ........
3019 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0xef6, ter=0x0
3022 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x2ad4, ter=0x0
3025 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x1efc, ter=0x0
3028 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x169d, ter=0x0
3030 [q, b, e, ?] ...Stopping timer
3032 [q, b, e, ?] ## Application terminated, rc = 0x0
3038 Over time, many people have reported problems when trying to use the
3039 "minicom" terminal emulation program for serial download. I (wd)
3040 consider minicom to be broken, and recommend not to use it. Under
3041 Unix, I recommend to use C-Kermit for general purpose use (and
3042 especially for kermit binary protocol download ("loadb" command), and
3043 use "cu" for S-Record download ("loads" command).
3045 Nevertheless, if you absolutely want to use it try adding this
3046 configuration to your "File transfer protocols" section:
3048 Name Program Name U/D FullScr IO-Red. Multi
3049 X kermit /usr/bin/kermit -i -l %l -s Y U Y N N
3050 Y kermit /usr/bin/kermit -i -l %l -r N D Y N N
3056 Starting at version 0.9.2, U-Boot supports NetBSD both as host
3057 (build U-Boot) and target system (boots NetBSD/mpc8xx).
3059 Building requires a cross environment; it is known to work on
3060 NetBSD/i386 with the cross-powerpc-netbsd-1.3 package (you will also
3061 need gmake since the Makefiles are not compatible with BSD make).
3062 Note that the cross-powerpc package does not install include files;
3063 attempting to build U-Boot will fail because <machine/ansi.h> is
3064 missing. This file has to be installed and patched manually:
3066 # cd /usr/pkg/cross/powerpc-netbsd/include
3068 # ln -s powerpc machine
3069 # cp /usr/src/sys/arch/powerpc/include/ansi.h powerpc/ansi.h
3070 # ${EDIT} powerpc/ansi.h ## must remove __va_list, _BSD_VA_LIST
3072 Native builds *don't* work due to incompatibilities between native
3073 and U-Boot include files.
3075 Booting assumes that (the first part of) the image booted is a
3076 stage-2 loader which in turn loads and then invokes the kernel
3077 proper. Loader sources will eventually appear in the NetBSD source
3078 tree (probably in sys/arc/mpc8xx/stand/u-boot_stage2/); in the
3079 meantime, send mail to bruno@exet-ag.de and/or wd@denx.de for
3083 Implementation Internals:
3084 =========================
3086 The following is not intended to be a complete description of every
3087 implementation detail. However, it should help to understand the
3088 inner workings of U-Boot and make it easier to port it to custom
3092 Initial Stack, Global Data:
3093 ---------------------------
3095 The implementation of U-Boot is complicated by the fact that U-Boot
3096 starts running out of ROM (flash memory), usually without access to
3097 system RAM (because the memory controller is not initialized yet).
3098 This means that we don't have writable Data or BSS segments, and BSS
3099 is not initialized as zero. To be able to get a C environment working
3100 at all, we have to allocate at least a minimal stack. Implementation
3101 options for this are defined and restricted by the CPU used: Some CPU
3102 models provide on-chip memory (like the IMMR area on MPC8xx and
3103 MPC826x processors), on others (parts of) the data cache can be
3104 locked as (mis-) used as memory, etc.
3106 Chris Hallinan posted a good summary of these issues to the
3107 u-boot-users mailing list:
3109 Subject: RE: [U-Boot-Users] RE: More On Memory Bank x (nothingness)?
3110 From: "Chris Hallinan" <clh@net1plus.com>
3111 Date: Mon, 10 Feb 2003 16:43:46 -0500 (22:43 MET)
3114 Correct me if I'm wrong, folks, but the way I understand it
3115 is this: Using DCACHE as initial RAM for Stack, etc, does not
3116 require any physical RAM backing up the cache. The cleverness
3117 is that the cache is being used as a temporary supply of
3118 necessary storage before the SDRAM controller is setup. It's
3119 beyond the scope of this list to expain the details, but you
3120 can see how this works by studying the cache architecture and
3121 operation in the architecture and processor-specific manuals.
3123 OCM is On Chip Memory, which I believe the 405GP has 4K. It
3124 is another option for the system designer to use as an
3125 initial stack/ram area prior to SDRAM being available. Either
3126 option should work for you. Using CS 4 should be fine if your
3127 board designers haven't used it for something that would
3128 cause you grief during the initial boot! It is frequently not
3131 CFG_INIT_RAM_ADDR should be somewhere that won't interfere
3132 with your processor/board/system design. The default value
3133 you will find in any recent u-boot distribution in
3134 Walnut405.h should work for you. I'd set it to a value larger
3135 than your SDRAM module. If you have a 64MB SDRAM module, set
3136 it above 400_0000. Just make sure your board has no resources
3137 that are supposed to respond to that address! That code in
3138 start.S has been around a while and should work as is when
3139 you get the config right.
3144 It is essential to remember this, since it has some impact on the C
3145 code for the initialization procedures:
3147 * Initialized global data (data segment) is read-only. Do not attempt
3150 * Do not use any unitialized global data (or implicitely initialized
3151 as zero data - BSS segment) at all - this is undefined, initiali-
3152 zation is performed later (when relocating to RAM).
3154 * Stack space is very limited. Avoid big data buffers or things like
3157 Having only the stack as writable memory limits means we cannot use
3158 normal global data to share information beween the code. But it
3159 turned out that the implementation of U-Boot can be greatly
3160 simplified by making a global data structure (gd_t) available to all
3161 functions. We could pass a pointer to this data as argument to _all_
3162 functions, but this would bloat the code. Instead we use a feature of
3163 the GCC compiler (Global Register Variables) to share the data: we
3164 place a pointer (gd) to the global data into a register which we
3165 reserve for this purpose.
3167 When choosing a register for such a purpose we are restricted by the
3168 relevant (E)ABI specifications for the current architecture, and by
3169 GCC's implementation.
3171 For PowerPC, the following registers have specific use:
3174 R3-R4: parameter passing and return values
3175 R5-R10: parameter passing
3176 R13: small data area pointer
3180 (U-Boot also uses R14 as internal GOT pointer.)
3182 ==> U-Boot will use R29 to hold a pointer to the global data
3184 Note: on PPC, we could use a static initializer (since the
3185 address of the global data structure is known at compile time),
3186 but it turned out that reserving a register results in somewhat
3187 smaller code - although the code savings are not that big (on
3188 average for all boards 752 bytes for the whole U-Boot image,
3189 624 text + 127 data).
3191 On ARM, the following registers are used:
3193 R0: function argument word/integer result
3194 R1-R3: function argument word
3196 R10: stack limit (used only if stack checking if enabled)
3197 R11: argument (frame) pointer
3198 R12: temporary workspace
3201 R15: program counter
3203 ==> U-Boot will use R8 to hold a pointer to the global data
3209 U-Boot runs in system state and uses physical addresses, i.e. the
3210 MMU is not used either for address mapping nor for memory protection.
3212 The available memory is mapped to fixed addresses using the memory
3213 controller. In this process, a contiguous block is formed for each
3214 memory type (Flash, SDRAM, SRAM), even when it consists of several
3215 physical memory banks.
3217 U-Boot is installed in the first 128 kB of the first Flash bank (on
3218 TQM8xxL modules this is the range 0x40000000 ... 0x4001FFFF). After
3219 booting and sizing and initializing DRAM, the code relocates itself
3220 to the upper end of DRAM. Immediately below the U-Boot code some
3221 memory is reserved for use by malloc() [see CFG_MALLOC_LEN
3222 configuration setting]. Below that, a structure with global Board
3223 Info data is placed, followed by the stack (growing downward).
3225 Additionally, some exception handler code is copied to the low 8 kB
3226 of DRAM (0x00000000 ... 0x00001FFF).
3228 So a typical memory configuration with 16 MB of DRAM could look like
3231 0x0000 0000 Exception Vector code
3234 0x0000 2000 Free for Application Use
3240 0x00FB FF20 Monitor Stack (Growing downward)
3241 0x00FB FFAC Board Info Data and permanent copy of global data
3242 0x00FC 0000 Malloc Arena
3245 0x00FE 0000 RAM Copy of Monitor Code
3246 ... eventually: LCD or video framebuffer
3247 ... eventually: pRAM (Protected RAM - unchanged by reset)
3248 0x00FF FFFF [End of RAM]
3251 System Initialization:
3252 ----------------------
3254 In the reset configuration, U-Boot starts at the reset entry point
3255 (on most PowerPC systens at address 0x00000100). Because of the reset
3256 configuration for CS0# this is a mirror of the onboard Flash memory.
3257 To be able to re-map memory U-Boot then jumps to its link address.
3258 To be able to implement the initialization code in C, a (small!)
3259 initial stack is set up in the internal Dual Ported RAM (in case CPUs
3260 which provide such a feature like MPC8xx or MPC8260), or in a locked
3261 part of the data cache. After that, U-Boot initializes the CPU core,
3262 the caches and the SIU.
3264 Next, all (potentially) available memory banks are mapped using a
3265 preliminary mapping. For example, we put them on 512 MB boundaries
3266 (multiples of 0x20000000: SDRAM on 0x00000000 and 0x20000000, Flash
3267 on 0x40000000 and 0x60000000, SRAM on 0x80000000). Then UPM A is
3268 programmed for SDRAM access. Using the temporary configuration, a
3269 simple memory test is run that determines the size of the SDRAM
3272 When there is more than one SDRAM bank, and the banks are of
3273 different size, the largest is mapped first. For equal size, the first
3274 bank (CS2#) is mapped first. The first mapping is always for address
3275 0x00000000, with any additional banks following immediately to create
3276 contiguous memory starting from 0.
3278 Then, the monitor installs itself at the upper end of the SDRAM area
3279 and allocates memory for use by malloc() and for the global Board
3280 Info data; also, the exception vector code is copied to the low RAM
3281 pages, and the final stack is set up.
3283 Only after this relocation will you have a "normal" C environment;
3284 until that you are restricted in several ways, mostly because you are
3285 running from ROM, and because the code will have to be relocated to a
3289 U-Boot Porting Guide:
3290 ----------------------
3292 [Based on messages by Jerry Van Baren in the U-Boot-Users mailing
3296 int main (int argc, char *argv[])
3298 sighandler_t no_more_time;
3300 signal (SIGALRM, no_more_time);
3301 alarm (PROJECT_DEADLINE - toSec (3 * WEEK));
3303 if (available_money > available_manpower) {
3304 pay consultant to port U-Boot;
3308 Download latest U-Boot source;
3310 Subscribe to u-boot-users mailing list;
3313 email ("Hi, I am new to U-Boot, how do I get started?");
3317 Read the README file in the top level directory;
3318 Read http://www.denx.de/twiki/bin/view/DULG/Manual ;
3319 Read the source, Luke;
3322 if (available_money > toLocalCurrency ($2500)) {
3325 Add a lot of aggravation and time;
3328 Create your own board support subdirectory;
3330 Create your own board config file;
3334 Add / modify source code;
3338 email ("Hi, I am having problems...");
3340 Send patch file to Wolfgang;
3345 void no_more_time (int sig)
3354 All contributions to U-Boot should conform to the Linux kernel
3355 coding style; see the file "Documentation/CodingStyle" in your Linux
3356 kernel source directory.
3358 Please note that U-Boot is implemented in C (and to some small parts
3359 in Assembler); no C++ is used, so please do not use C++ style
3360 comments (//) in your code.
3362 Please also stick to the following formatting rules:
3363 - remove any trailing white space
3364 - use TAB characters for indentation, not spaces
3365 - make sure NOT to use DOS '\r\n' line feeds
3366 - do not add more than 2 empty lines to source files
3367 - do not add trailing empty lines to source files
3369 Submissions which do not conform to the standards may be returned
3370 with a request to reformat the changes.
3376 Since the number of patches for U-Boot is growing, we need to
3377 establish some rules. Submissions which do not conform to these rules
3378 may be rejected, even when they contain important and valuable stuff.
3381 When you send a patch, please include the following information with
3384 * For bug fixes: a description of the bug and how your patch fixes
3385 this bug. Please try to include a way of demonstrating that the
3386 patch actually fixes something.
3388 * For new features: a description of the feature and your
3391 * A CHANGELOG entry as plaintext (separate from the patch)
3393 * For major contributions, your entry to the CREDITS file
3395 * When you add support for a new board, don't forget to add this
3396 board to the MAKEALL script, too.
3398 * If your patch adds new configuration options, don't forget to
3399 document these in the README file.
3401 * The patch itself. If you are accessing the CVS repository use "cvs
3402 update; cvs diff -puRN"; else, use "diff -purN OLD NEW". If your
3403 version of diff does not support these options, then get the latest
3404 version of GNU diff.
3406 The current directory when running this command shall be the top
3407 level directory of the U-Boot source tree, or it's parent directory
3408 (i. e. please make sure that your patch includes sufficient
3409 directory information for the affected files).
3411 We accept patches as plain text, MIME attachments or as uuencoded
3414 * If one logical set of modifications affects or creates several
3415 files, all these changes shall be submitted in a SINGLE patch file.
3417 * Changesets that contain different, unrelated modifications shall be
3418 submitted as SEPARATE patches, one patch per changeset.
3423 * Before sending the patch, run the MAKEALL script on your patched
3424 source tree and make sure that no errors or warnings are reported
3425 for any of the boards.
3427 * Keep your modifications to the necessary minimum: A patch
3428 containing several unrelated changes or arbitrary reformats will be
3429 returned with a request to re-formatting / split it.
3431 * If you modify existing code, make sure that your new code does not
3432 add to the memory footprint of the code ;-) Small is beautiful!
3433 When adding new features, these should compile conditionally only
3434 (using #ifdef), and the resulting code with the new feature
3435 disabled must not need more memory than the old code without your
projects / u-boot / blob