1# 2# (C) Copyright 2000 - 2008 3# Wolfgang Denk, DENX Software Engineering, wd@denx.de. 4# 5# See file CREDITS for list of people who contributed to this 6# project. 7# 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. 12# 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. 17# 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, 21# MA 02111-1307 USA 22# 23 24Summary: 25======== 26 27This directory contains the source code for U-Boot, a boot loader for 28Embedded boards based on PowerPC, ARM, MIPS and several other 29processors, which can be installed in a boot ROM and used to 30initialize and test the hardware or to download and run application 31code. 32 33The development of U-Boot is closely related to Linux: some parts of 34the source code originate in the Linux source tree, we have some 35header files in common, and special provision has been made to 36support booting of Linux images. 37 38Some attention has been paid to make this software easily 39configurable and extendable. For instance, all monitor commands are 40implemented with the same call interface, so that it's very easy to 41add new commands. Also, instead of permanently adding rarely used 42code (for instance hardware test utilities) to the monitor, you can 43load and run it dynamically. 44 45 46Status: 47======= 48 49In general, all boards for which a configuration option exists in the 50Makefile have been tested to some extent and can be considered 51"working". In fact, many of them are used in production systems. 52 53In case of problems see the CHANGELOG and CREDITS files to find out 54who contributed the specific port. The MAINTAINERS file lists board 55maintainers. 56 57 58Where to get help: 59================== 60 61In case you have questions about, problems with or contributions for 62U-Boot you should send a message to the U-Boot mailing list at 63<u-boot-users@lists.sourceforge.net>. There is also an archive of 64previous traffic on the mailing list - please search the archive 65before asking FAQ's. Please see 66http://lists.sourceforge.net/lists/listinfo/u-boot-users/ 67 68 69Where to get source code: 70========================= 71 72The U-Boot source code is maintained in the git repository at 73git://www.denx.de/git/u-boot.git ; you can browse it online at 74http://www.denx.de/cgi-bin/gitweb.cgi?p=u-boot.git;a=summary 75 76The "snapshot" links on this page allow you to download tarballs of 77any version you might be interested in. Ofifcial releases are also 78available for FTP download from the ftp://ftp.denx.de/pub/u-boot/ 79directory. 80 81Pre-built (and tested) images are available from 82ftp://ftp.denx.de/pub/u-boot/images/ 83 84 85Where we come from: 86=================== 87 88- start from 8xxrom sources 89- create PPCBoot project (http://sourceforge.net/projects/ppcboot) 90- clean up code 91- make it easier to add custom boards 92- make it possible to add other [PowerPC] CPUs 93- extend functions, especially: 94 * Provide extended interface to Linux boot loader 95 * S-Record download 96 * network boot 97 * PCMCIA / CompactFLash / ATA disk / SCSI ... boot 98- create ARMBoot project (http://sourceforge.net/projects/armboot) 99- add other CPU families (starting with ARM) 100- create U-Boot project (http://sourceforge.net/projects/u-boot) 101- current project page: see http://www.denx.de/wiki/UBoot 102 103 104Names and Spelling: 105=================== 106 107The "official" name of this project is "Das U-Boot". The spelling 108"U-Boot" shall be used in all written text (documentation, comments 109in source files etc.). Example: 110 111 This is the README file for the U-Boot project. 112 113File names etc. shall be based on the string "u-boot". Examples: 114 115 include/asm-ppc/u-boot.h 116 117 #include <asm/u-boot.h> 118 119Variable names, preprocessor constants etc. shall be either based on 120the string "u_boot" or on "U_BOOT". Example: 121 122 U_BOOT_VERSION u_boot_logo 123 IH_OS_U_BOOT u_boot_hush_start 124 125 126Versioning: 127=========== 128 129U-Boot uses a 3 level version number containing a version, a 130sub-version, and a patchlevel: "U-Boot-2.34.5" means version "2", 131sub-version "34", and patchlevel "4". 132 133The patchlevel is used to indicate certain stages of development 134between released versions, i. e. officially released versions of 135U-Boot will always have a patchlevel of "0". 136 137 138Directory Hierarchy: 139==================== 140 141- board Board dependent files 142- common Misc architecture independent functions 143- cpu CPU specific files 144 - 74xx_7xx Files specific to Freescale MPC74xx and 7xx CPUs 145 - arm720t Files specific to ARM 720 CPUs 146 - arm920t Files specific to ARM 920 CPUs 147 - at91rm9200 Files specific to Atmel AT91RM9200 CPU 148 - imx Files specific to Freescale MC9328 i.MX CPUs 149 - s3c24x0 Files specific to Samsung S3C24X0 CPUs 150 - arm925t Files specific to ARM 925 CPUs 151 - arm926ejs Files specific to ARM 926 CPUs 152 - arm1136 Files specific to ARM 1136 CPUs 153 - at32ap Files specific to Atmel AVR32 AP CPUs 154 - i386 Files specific to i386 CPUs 155 - ixp Files specific to Intel XScale IXP CPUs 156 - leon2 Files specific to Gaisler LEON2 SPARC CPU 157 - leon3 Files specific to Gaisler LEON3 SPARC CPU 158 - mcf52x2 Files specific to Freescale ColdFire MCF52x2 CPUs 159 - mcf5227x Files specific to Freescale ColdFire MCF5227x CPUs 160 - mcf532x Files specific to Freescale ColdFire MCF5329 CPUs 161 - mcf5445x Files specific to Freescale ColdFire MCF5445x CPUs 162 - mcf547x_8x Files specific to Freescale ColdFire MCF547x_8x CPUs 163 - mips Files specific to MIPS CPUs 164 - mpc5xx Files specific to Freescale MPC5xx CPUs 165 - mpc5xxx Files specific to Freescale MPC5xxx CPUs 166 - mpc8xx Files specific to Freescale MPC8xx CPUs 167 - mpc8220 Files specific to Freescale MPC8220 CPUs 168 - mpc824x Files specific to Freescale MPC824x CPUs 169 - mpc8260 Files specific to Freescale MPC8260 CPUs 170 - mpc85xx Files specific to Freescale MPC85xx CPUs 171 - nios Files specific to Altera NIOS CPUs 172 - nios2 Files specific to Altera Nios-II CPUs 173 - ppc4xx Files specific to AMCC PowerPC 4xx CPUs 174 - pxa Files specific to Intel XScale PXA CPUs 175 - s3c44b0 Files specific to Samsung S3C44B0 CPUs 176 - sa1100 Files specific to Intel StrongARM SA1100 CPUs 177- disk Code for disk drive partition handling 178- doc Documentation (don't expect too much) 179- drivers Commonly used device drivers 180- dtt Digital Thermometer and Thermostat drivers 181- examples Example code for standalone applications, etc. 182- include Header Files 183- lib_arm Files generic to ARM architecture 184- lib_avr32 Files generic to AVR32 architecture 185- lib_generic Files generic to all architectures 186- lib_i386 Files generic to i386 architecture 187- lib_m68k Files generic to m68k architecture 188- lib_mips Files generic to MIPS architecture 189- lib_nios Files generic to NIOS architecture 190- lib_ppc Files generic to PowerPC architecture 191- lib_sparc Files generic to SPARC architecture 192- libfdt Library files to support flattened device trees 193- net Networking code 194- post Power On Self Test 195- rtc Real Time Clock drivers 196- tools Tools to build S-Record or U-Boot images, etc. 197 198Software Configuration: 199======================= 200 201Configuration is usually done using C preprocessor defines; the 202rationale behind that is to avoid dead code whenever possible. 203 204There are two classes of configuration variables: 205 206* Configuration _OPTIONS_: 207 These are selectable by the user and have names beginning with 208 "CONFIG_". 209 210* Configuration _SETTINGS_: 211 These depend on the hardware etc. and should not be meddled with if 212 you don't know what you're doing; they have names beginning with 213 "CFG_". 214 215Later we will add a configuration tool - probably similar to or even 216identical to what's used for the Linux kernel. Right now, we have to 217do the configuration by hand, which means creating some symbolic 218links and editing some configuration files. We use the TQM8xxL boards 219as an example here. 220 221 222Selection of Processor Architecture and Board Type: 223--------------------------------------------------- 224 225For all supported boards there are ready-to-use default 226configurations available; just type "make <board_name>_config". 227 228Example: For a TQM823L module type: 229 230 cd u-boot 231 make TQM823L_config 232 233For the Cogent platform, you need to specify the cpu type as well; 234e.g. "make cogent_mpc8xx_config". And also configure the cogent 235directory according to the instructions in cogent/README. 236 237 238Configuration Options: 239---------------------- 240 241Configuration depends on the combination of board and CPU type; all 242such information is kept in a configuration file 243"include/configs/<board_name>.h". 244 245Example: For a TQM823L module, all configuration settings are in 246"include/configs/TQM823L.h". 247 248 249Many of the options are named exactly as the corresponding Linux 250kernel configuration options. The intention is to make it easier to 251build a config tool - later. 252 253 254The following options need to be configured: 255 256- CPU Type: Define exactly one, e.g. CONFIG_MPC85XX. 257 258- Board Type: Define exactly one, e.g. CONFIG_MPC8540ADS. 259 260- CPU Daughterboard Type: (if CONFIG_ATSTK1000 is defined) 261 Define exactly one, e.g. CONFIG_ATSTK1002 262 263- CPU Module Type: (if CONFIG_COGENT is defined) 264 Define exactly one of 265 CONFIG_CMA286_60_OLD 266--- FIXME --- not tested yet: 267 CONFIG_CMA286_60, CONFIG_CMA286_21, CONFIG_CMA286_60P, 268 CONFIG_CMA287_23, CONFIG_CMA287_50 269 270- Motherboard Type: (if CONFIG_COGENT is defined) 271 Define exactly one of 272 CONFIG_CMA101, CONFIG_CMA102 273 274- Motherboard I/O Modules: (if CONFIG_COGENT is defined) 275 Define one or more of 276 CONFIG_CMA302 277 278- Motherboard Options: (if CONFIG_CMA101 or CONFIG_CMA102 are defined) 279 Define one or more of 280 CONFIG_LCD_HEARTBEAT - update a character position on 281 the lcd display every second with 282 a "rotator" |\-/|\-/ 283 284- Board flavour: (if CONFIG_MPC8260ADS is defined) 285 CONFIG_ADSTYPE 286 Possible values are: 287 CFG_8260ADS - original MPC8260ADS 288 CFG_8266ADS - MPC8266ADS 289 CFG_PQ2FADS - PQ2FADS-ZU or PQ2FADS-VR 290 CFG_8272ADS - MPC8272ADS 291 292- MPC824X Family Member (if CONFIG_MPC824X is defined) 293 Define exactly one of 294 CONFIG_MPC8240, CONFIG_MPC8245 295 296- 8xx CPU Options: (if using an MPC8xx cpu) 297 CONFIG_8xx_GCLK_FREQ - deprecated: CPU clock if 298 get_gclk_freq() cannot work 299 e.g. if there is no 32KHz 300 reference PIT/RTC clock 301 CONFIG_8xx_OSCLK - PLL input clock (either EXTCLK 302 or XTAL/EXTAL) 303 304- 859/866/885 CPU options: (if using a MPC859 or MPC866 or MPC885 CPU): 305 CFG_8xx_CPUCLK_MIN 306 CFG_8xx_CPUCLK_MAX 307 CONFIG_8xx_CPUCLK_DEFAULT 308 See doc/README.MPC866 309 310 CFG_MEASURE_CPUCLK 311 312 Define this to measure the actual CPU clock instead 313 of relying on the correctness of the configured 314 values. Mostly useful for board bringup to make sure 315 the PLL is locked at the intended frequency. Note 316 that this requires a (stable) reference clock (32 kHz 317 RTC clock or CFG_8XX_XIN) 318 319- Intel Monahans options: 320 CFG_MONAHANS_RUN_MODE_OSC_RATIO 321 322 Defines the Monahans run mode to oscillator 323 ratio. Valid values are 8, 16, 24, 31. The core 324 frequency is this value multiplied by 13 MHz. 325 326 CFG_MONAHANS_TURBO_RUN_MODE_RATIO 327 328 Defines the Monahans turbo mode to oscillator 329 ratio. Valid values are 1 (default if undefined) and 330 2. The core frequency as calculated above is multiplied 331 by this value. 332 333- Linux Kernel Interface: 334 CONFIG_CLOCKS_IN_MHZ 335 336 U-Boot stores all clock information in Hz 337 internally. For binary compatibility with older Linux 338 kernels (which expect the clocks passed in the 339 bd_info data to be in MHz) the environment variable 340 "clocks_in_mhz" can be defined so that U-Boot 341 converts clock data to MHZ before passing it to the 342 Linux kernel. 343 When CONFIG_CLOCKS_IN_MHZ is defined, a definition of 344 "clocks_in_mhz=1" is automatically included in the 345 default environment. 346 347 CONFIG_MEMSIZE_IN_BYTES [relevant for MIPS only] 348 349 When transfering memsize parameter to linux, some versions 350 expect it to be in bytes, others in MB. 351 Define CONFIG_MEMSIZE_IN_BYTES to make it in bytes. 352 353 CONFIG_OF_LIBFDT / CONFIG_OF_FLAT_TREE 354 355 New kernel versions are expecting firmware settings to be 356 passed using flattened device trees (based on open firmware 357 concepts). 358 359 CONFIG_OF_LIBFDT 360 * New libfdt-based support 361 * Adds the "fdt" command 362 * The bootm command automatically updates the fdt 363 364 CONFIG_OF_FLAT_TREE 365 * Deprecated, see CONFIG_OF_LIBFDT 366 * Original ft_build.c-based support 367 * Automatically modifies the dft as part of the bootm command 368 * The environment variable "disable_of", when set, 369 disables this functionality. 370 371 OF_CPU - The proper name of the cpus node. 372 OF_SOC - The proper name of the soc node. 373 OF_TBCLK - The timebase frequency. 374 OF_STDOUT_PATH - The path to the console device 375 376 boards with QUICC Engines require OF_QE to set UCC mac addresses 377 378 CONFIG_OF_BOARD_SETUP 379 380 Board code has addition modification that it wants to make 381 to the flat device tree before handing it off to the kernel 382 383 CONFIG_OF_BOOT_CPU 384 385 This define fills in the correct boot cpu in the boot 386 param header, the default value is zero if undefined. 387 388- Serial Ports: 389 CFG_PL010_SERIAL 390 391 Define this if you want support for Amba PrimeCell PL010 UARTs. 392 393 CFG_PL011_SERIAL 394 395 Define this if you want support for Amba PrimeCell PL011 UARTs. 396 397 CONFIG_PL011_CLOCK 398 399 If you have Amba PrimeCell PL011 UARTs, set this variable to 400 the clock speed of the UARTs. 401 402 CONFIG_PL01x_PORTS 403 404 If you have Amba PrimeCell PL010 or PL011 UARTs on your board, 405 define this to a list of base addresses for each (supported) 406 port. See e.g. include/configs/versatile.h 407 408 409- Console Interface: 410 Depending on board, define exactly one serial port 411 (like CONFIG_8xx_CONS_SMC1, CONFIG_8xx_CONS_SMC2, 412 CONFIG_8xx_CONS_SCC1, ...), or switch off the serial 413 console by defining CONFIG_8xx_CONS_NONE 414 415 Note: if CONFIG_8xx_CONS_NONE is defined, the serial 416 port routines must be defined elsewhere 417 (i.e. serial_init(), serial_getc(), ...) 418 419 CONFIG_CFB_CONSOLE 420 Enables console device for a color framebuffer. Needs following 421 defines (cf. smiLynxEM, i8042, board/eltec/bab7xx) 422 VIDEO_FB_LITTLE_ENDIAN graphic memory organisation 423 (default big endian) 424 VIDEO_HW_RECTFILL graphic chip supports 425 rectangle fill 426 (cf. smiLynxEM) 427 VIDEO_HW_BITBLT graphic chip supports 428 bit-blit (cf. smiLynxEM) 429 VIDEO_VISIBLE_COLS visible pixel columns 430 (cols=pitch) 431 VIDEO_VISIBLE_ROWS visible pixel rows 432 VIDEO_PIXEL_SIZE bytes per pixel 433 VIDEO_DATA_FORMAT graphic data format 434 (0-5, cf. cfb_console.c) 435 VIDEO_FB_ADRS framebuffer address 436 VIDEO_KBD_INIT_FCT keyboard int fct 437 (i.e. i8042_kbd_init()) 438 VIDEO_TSTC_FCT test char fct 439 (i.e. i8042_tstc) 440 VIDEO_GETC_FCT get char fct 441 (i.e. i8042_getc) 442 CONFIG_CONSOLE_CURSOR cursor drawing on/off 443 (requires blink timer 444 cf. i8042.c) 445 CFG_CONSOLE_BLINK_COUNT blink interval (cf. i8042.c) 446 CONFIG_CONSOLE_TIME display time/date info in 447 upper right corner 448 (requires CONFIG_CMD_DATE) 449 CONFIG_VIDEO_LOGO display Linux logo in 450 upper left corner 451 CONFIG_VIDEO_BMP_LOGO use bmp_logo.h instead of 452 linux_logo.h for logo. 453 Requires CONFIG_VIDEO_LOGO 454 CONFIG_CONSOLE_EXTRA_INFO 455 addional board info beside 456 the logo 457 458 When CONFIG_CFB_CONSOLE is defined, video console is 459 default i/o. Serial console can be forced with 460 environment 'console=serial'. 461 462 When CONFIG_SILENT_CONSOLE is defined, all console 463 messages (by U-Boot and Linux!) can be silenced with 464 the "silent" environment variable. See 465 doc/README.silent for more information. 466 467- Console Baudrate: 468 CONFIG_BAUDRATE - in bps 469 Select one of the baudrates listed in 470 CFG_BAUDRATE_TABLE, see below. 471 CFG_BRGCLK_PRESCALE, baudrate prescale 472 473- Interrupt driven serial port input: 474 CONFIG_SERIAL_SOFTWARE_FIFO 475 476 PPC405GP only. 477 Use an interrupt handler for receiving data on the 478 serial port. It also enables using hardware handshake 479 (RTS/CTS) and UART's built-in FIFO. Set the number of 480 bytes the interrupt driven input buffer should have. 481 482 Leave undefined to disable this feature, including 483 disable the buffer and hardware handshake. 484 485- Console UART Number: 486 CONFIG_UART1_CONSOLE 487 488 AMCC PPC4xx only. 489 If defined internal UART1 (and not UART0) is used 490 as default U-Boot console. 491 492- Boot Delay: CONFIG_BOOTDELAY - in seconds 493 Delay before automatically booting the default image; 494 set to -1 to disable autoboot. 495 496 See doc/README.autoboot for these options that 497 work with CONFIG_BOOTDELAY. None are required. 498 CONFIG_BOOT_RETRY_TIME 499 CONFIG_BOOT_RETRY_MIN 500 CONFIG_AUTOBOOT_KEYED 501 CONFIG_AUTOBOOT_PROMPT 502 CONFIG_AUTOBOOT_DELAY_STR 503 CONFIG_AUTOBOOT_STOP_STR 504 CONFIG_AUTOBOOT_DELAY_STR2 505 CONFIG_AUTOBOOT_STOP_STR2 506 CONFIG_ZERO_BOOTDELAY_CHECK 507 CONFIG_RESET_TO_RETRY 508 509- Autoboot Command: 510 CONFIG_BOOTCOMMAND 511 Only needed when CONFIG_BOOTDELAY is enabled; 512 define a command string that is automatically executed 513 when no character is read on the console interface 514 within "Boot Delay" after reset. 515 516 CONFIG_BOOTARGS 517 This can be used to pass arguments to the bootm 518 command. The value of CONFIG_BOOTARGS goes into the 519 environment value "bootargs". 520 521 CONFIG_RAMBOOT and CONFIG_NFSBOOT 522 The value of these goes into the environment as 523 "ramboot" and "nfsboot" respectively, and can be used 524 as a convenience, when switching between booting from 525 ram and nfs. 526 527- Pre-Boot Commands: 528 CONFIG_PREBOOT 529 530 When this option is #defined, the existence of the 531 environment variable "preboot" will be checked 532 immediately before starting the CONFIG_BOOTDELAY 533 countdown and/or running the auto-boot command resp. 534 entering interactive mode. 535 536 This feature is especially useful when "preboot" is 537 automatically generated or modified. For an example 538 see the LWMON board specific code: here "preboot" is 539 modified when the user holds down a certain 540 combination of keys on the (special) keyboard when 541 booting the systems 542 543- Serial Download Echo Mode: 544 CONFIG_LOADS_ECHO 545 If defined to 1, all characters received during a 546 serial download (using the "loads" command) are 547 echoed back. This might be needed by some terminal 548 emulations (like "cu"), but may as well just take 549 time on others. This setting #define's the initial 550 value of the "loads_echo" environment variable. 551 552- Kgdb Serial Baudrate: (if CONFIG_CMD_KGDB is defined) 553 CONFIG_KGDB_BAUDRATE 554 Select one of the baudrates listed in 555 CFG_BAUDRATE_TABLE, see below. 556 557- Monitor Functions: 558 Monitor commands can be included or excluded 559 from the build by using the #include files 560 "config_cmd_all.h" and #undef'ing unwanted 561 commands, or using "config_cmd_default.h" 562 and augmenting with additional #define's 563 for wanted commands. 564 565 The default command configuration includes all commands 566 except those marked below with a "*". 567 568 CONFIG_CMD_ASKENV * ask for env variable 569 CONFIG_CMD_AUTOSCRIPT Autoscript Support 570 CONFIG_CMD_BDI bdinfo 571 CONFIG_CMD_BEDBUG * Include BedBug Debugger 572 CONFIG_CMD_BMP * BMP support 573 CONFIG_CMD_BSP * Board specific commands 574 CONFIG_CMD_BOOTD bootd 575 CONFIG_CMD_CACHE * icache, dcache 576 CONFIG_CMD_CONSOLE coninfo 577 CONFIG_CMD_DATE * support for RTC, date/time... 578 CONFIG_CMD_DHCP * DHCP support 579 CONFIG_CMD_DIAG * Diagnostics 580 CONFIG_CMD_DOC * Disk-On-Chip Support 581 CONFIG_CMD_DTT * Digital Therm and Thermostat 582 CONFIG_CMD_ECHO echo arguments 583 CONFIG_CMD_EEPROM * EEPROM read/write support 584 CONFIG_CMD_ELF * bootelf, bootvx 585 CONFIG_CMD_ENV saveenv 586 CONFIG_CMD_FDC * Floppy Disk Support 587 CONFIG_CMD_FAT * FAT partition support 588 CONFIG_CMD_FDOS * Dos diskette Support 589 CONFIG_CMD_FLASH flinfo, erase, protect 590 CONFIG_CMD_FPGA FPGA device initialization support 591 CONFIG_CMD_HWFLOW * RTS/CTS hw flow control 592 CONFIG_CMD_I2C * I2C serial bus support 593 CONFIG_CMD_IDE * IDE harddisk support 594 CONFIG_CMD_IMI iminfo 595 CONFIG_CMD_IMLS List all found images 596 CONFIG_CMD_IMMAP * IMMR dump support 597 CONFIG_CMD_IRQ * irqinfo 598 CONFIG_CMD_ITEST Integer/string test of 2 values 599 CONFIG_CMD_JFFS2 * JFFS2 Support 600 CONFIG_CMD_KGDB * kgdb 601 CONFIG_CMD_LOADB loadb 602 CONFIG_CMD_LOADS loads 603 CONFIG_CMD_MEMORY md, mm, nm, mw, cp, cmp, crc, base, 604 loop, loopw, mtest 605 CONFIG_CMD_MISC Misc functions like sleep etc 606 CONFIG_CMD_MMC * MMC memory mapped support 607 CONFIG_CMD_MII * MII utility commands 608 CONFIG_CMD_NAND * NAND support 609 CONFIG_CMD_NET bootp, tftpboot, rarpboot 610 CONFIG_CMD_PCI * pciinfo 611 CONFIG_CMD_PCMCIA * PCMCIA support 612 CONFIG_CMD_PING * send ICMP ECHO_REQUEST to network 613 host 614 CONFIG_CMD_PORTIO * Port I/O 615 CONFIG_CMD_REGINFO * Register dump 616 CONFIG_CMD_RUN run command in env variable 617 CONFIG_CMD_SAVES * save S record dump 618 CONFIG_CMD_SCSI * SCSI Support 619 CONFIG_CMD_SDRAM * print SDRAM configuration information 620 (requires CONFIG_CMD_I2C) 621 CONFIG_CMD_SETGETDCR Support for DCR Register access 622 (4xx only) 623 CONFIG_CMD_SPI * SPI serial bus support 624 CONFIG_CMD_USB * USB support 625 CONFIG_CMD_VFD * VFD support (TRAB) 626 CONFIG_CMD_BSP * Board SPecific functions 627 CONFIG_CMD_CDP * Cisco Discover Protocol support 628 CONFIG_CMD_FSL * Microblaze FSL support 629 630 631 EXAMPLE: If you want all functions except of network 632 support you can write: 633 634 #include "config_cmd_all.h" 635 #undef CONFIG_CMD_NET 636 637 Other Commands: 638 fdt (flattened device tree) command: CONFIG_OF_LIBFDT 639 640 Note: Don't enable the "icache" and "dcache" commands 641 (configuration option CONFIG_CMD_CACHE) unless you know 642 what you (and your U-Boot users) are doing. Data 643 cache cannot be enabled on systems like the 8xx or 644 8260 (where accesses to the IMMR region must be 645 uncached), and it cannot be disabled on all other 646 systems where we (mis-) use the data cache to hold an 647 initial stack and some data. 648 649 650 XXX - this list needs to get updated! 651 652- Watchdog: 653 CONFIG_WATCHDOG 654 If this variable is defined, it enables watchdog 655 support. There must be support in the platform specific 656 code for a watchdog. For the 8xx and 8260 CPUs, the 657 SIU Watchdog feature is enabled in the SYPCR 658 register. 659 660- U-Boot Version: 661 CONFIG_VERSION_VARIABLE 662 If this variable is defined, an environment variable 663 named "ver" is created by U-Boot showing the U-Boot 664 version as printed by the "version" command. 665 This variable is readonly. 666 667- Real-Time Clock: 668 669 When CONFIG_CMD_DATE is selected, the type of the RTC 670 has to be selected, too. Define exactly one of the 671 following options: 672 673 CONFIG_RTC_MPC8xx - use internal RTC of MPC8xx 674 CONFIG_RTC_PCF8563 - use Philips PCF8563 RTC 675 CONFIG_RTC_MC13783 - use MC13783 RTC 676 CONFIG_RTC_MC146818 - use MC146818 RTC 677 CONFIG_RTC_DS1307 - use Maxim, Inc. DS1307 RTC 678 CONFIG_RTC_DS1337 - use Maxim, Inc. DS1337 RTC 679 CONFIG_RTC_DS1338 - use Maxim, Inc. DS1338 RTC 680 CONFIG_RTC_DS164x - use Dallas DS164x RTC 681 CONFIG_RTC_ISL1208 - use Intersil ISL1208 RTC 682 CONFIG_RTC_MAX6900 - use Maxim, Inc. MAX6900 RTC 683 CFG_RTC_DS1337_NOOSC - Turn off the OSC output for DS1337 684 685 Note that if the RTC uses I2C, then the I2C interface 686 must also be configured. See I2C Support, below. 687 688- Timestamp Support: 689 690 When CONFIG_TIMESTAMP is selected, the timestamp 691 (date and time) of an image is printed by image 692 commands like bootm or iminfo. This option is 693 automatically enabled when you select CONFIG_CMD_DATE . 694 695- Partition Support: 696 CONFIG_MAC_PARTITION and/or CONFIG_DOS_PARTITION 697 and/or CONFIG_ISO_PARTITION 698 699 If IDE or SCSI support is enabled (CONFIG_CMD_IDE or 700 CONFIG_CMD_SCSI) you must configure support for at 701 least one partition type as well. 702 703- IDE Reset method: 704 CONFIG_IDE_RESET_ROUTINE - this is defined in several 705 board configurations files but used nowhere! 706 707 CONFIG_IDE_RESET - is this is defined, IDE Reset will 708 be performed by calling the function 709 ide_set_reset(int reset) 710 which has to be defined in a board specific file 711 712- ATAPI Support: 713 CONFIG_ATAPI 714 715 Set this to enable ATAPI support. 716 717- LBA48 Support 718 CONFIG_LBA48 719 720 Set this to enable support for disks larger than 137GB 721 Also look at CFG_64BIT_LBA ,CFG_64BIT_VSPRINTF and CFG_64BIT_STRTOUL 722 Whithout these , LBA48 support uses 32bit variables and will 'only' 723 support disks up to 2.1TB. 724 725 CFG_64BIT_LBA: 726 When enabled, makes the IDE subsystem use 64bit sector addresses. 727 Default is 32bit. 728 729- SCSI Support: 730 At the moment only there is only support for the 731 SYM53C8XX SCSI controller; define 732 CONFIG_SCSI_SYM53C8XX to enable it. 733 734 CFG_SCSI_MAX_LUN [8], CFG_SCSI_MAX_SCSI_ID [7] and 735 CFG_SCSI_MAX_DEVICE [CFG_SCSI_MAX_SCSI_ID * 736 CFG_SCSI_MAX_LUN] can be adjusted to define the 737 maximum numbers of LUNs, SCSI ID's and target 738 devices. 739 CFG_SCSI_SYM53C8XX_CCF to fix clock timing (80Mhz) 740 741- NETWORK Support (PCI): 742 CONFIG_E1000 743 Support for Intel 8254x gigabit chips. 744 745 CONFIG_E1000_FALLBACK_MAC 746 default MAC for empty eeprom after production. 747 748 CONFIG_EEPRO100 749 Support for Intel 82557/82559/82559ER chips. 750 Optional CONFIG_EEPRO100_SROM_WRITE enables eeprom 751 write routine for first time initialisation. 752 753 CONFIG_TULIP 754 Support for Digital 2114x chips. 755 Optional CONFIG_TULIP_SELECT_MEDIA for board specific 756 modem chip initialisation (KS8761/QS6611). 757 758 CONFIG_NATSEMI 759 Support for National dp83815 chips. 760 761 CONFIG_NS8382X 762 Support for National dp8382[01] gigabit chips. 763 764- NETWORK Support (other): 765 766 CONFIG_DRIVER_LAN91C96 767 Support for SMSC's LAN91C96 chips. 768 769 CONFIG_LAN91C96_BASE 770 Define this to hold the physical address 771 of the LAN91C96's I/O space 772 773 CONFIG_LAN91C96_USE_32_BIT 774 Define this to enable 32 bit addressing 775 776 CONFIG_DRIVER_SMC91111 777 Support for SMSC's LAN91C111 chip 778 779 CONFIG_SMC91111_BASE 780 Define this to hold the physical address 781 of the device (I/O space) 782 783 CONFIG_SMC_USE_32_BIT 784 Define this if data bus is 32 bits 785 786 CONFIG_SMC_USE_IOFUNCS 787 Define this to use i/o functions instead of macros 788 (some hardware wont work with macros) 789 790- USB Support: 791 At the moment only the UHCI host controller is 792 supported (PIP405, MIP405, MPC5200); define 793 CONFIG_USB_UHCI to enable it. 794 define CONFIG_USB_KEYBOARD to enable the USB Keyboard 795 and define CONFIG_USB_STORAGE to enable the USB 796 storage devices. 797 Note: 798 Supported are USB Keyboards and USB Floppy drives 799 (TEAC FD-05PUB). 800 MPC5200 USB requires additional defines: 801 CONFIG_USB_CLOCK 802 for 528 MHz Clock: 0x0001bbbb 803 CONFIG_USB_CONFIG 804 for differential drivers: 0x00001000 805 for single ended drivers: 0x00005000 806 CFG_USB_EVENT_POLL 807 May be defined to allow interrupt polling 808 instead of using asynchronous interrupts 809 810- USB Device: 811 Define the below if you wish to use the USB console. 812 Once firmware is rebuilt from a serial console issue the 813 command "setenv stdin usbtty; setenv stdout usbtty" and 814 attach your usb cable. The Unix command "dmesg" should print 815 it has found a new device. The environment variable usbtty 816 can be set to gserial or cdc_acm to enable your device to 817 appear to a USB host as a Linux gserial device or a 818 Common Device Class Abstract Control Model serial device. 819 If you select usbtty = gserial you should be able to enumerate 820 a Linux host by 821 # modprobe usbserial vendor=0xVendorID product=0xProductID 822 else if using cdc_acm, simply setting the environment 823 variable usbtty to be cdc_acm should suffice. The following 824 might be defined in YourBoardName.h 825 826 CONFIG_USB_DEVICE 827 Define this to build a UDC device 828 829 CONFIG_USB_TTY 830 Define this to have a tty type of device available to 831 talk to the UDC device 832 833 CFG_CONSOLE_IS_IN_ENV 834 Define this if you want stdin, stdout &/or stderr to 835 be set to usbtty. 836 837 mpc8xx: 838 CFG_USB_EXTC_CLK 0xBLAH 839 Derive USB clock from external clock "blah" 840 - CFG_USB_EXTC_CLK 0x02 841 842 CFG_USB_BRG_CLK 0xBLAH 843 Derive USB clock from brgclk 844 - CFG_USB_BRG_CLK 0x04 845 846 If you have a USB-IF assigned VendorID then you may wish to 847 define your own vendor specific values either in BoardName.h 848 or directly in usbd_vendor_info.h. If you don't define 849 CONFIG_USBD_MANUFACTURER, CONFIG_USBD_PRODUCT_NAME, 850 CONFIG_USBD_VENDORID and CONFIG_USBD_PRODUCTID, then U-Boot 851 should pretend to be a Linux device to it's target host. 852 853 CONFIG_USBD_MANUFACTURER 854 Define this string as the name of your company for 855 - CONFIG_USBD_MANUFACTURER "my company" 856 857 CONFIG_USBD_PRODUCT_NAME 858 Define this string as the name of your product 859 - CONFIG_USBD_PRODUCT_NAME "acme usb device" 860 861 CONFIG_USBD_VENDORID 862 Define this as your assigned Vendor ID from the USB 863 Implementors Forum. This *must* be a genuine Vendor ID 864 to avoid polluting the USB namespace. 865 - CONFIG_USBD_VENDORID 0xFFFF 866 867 CONFIG_USBD_PRODUCTID 868 Define this as the unique Product ID 869 for your device 870 - CONFIG_USBD_PRODUCTID 0xFFFF 871 872 873- MMC Support: 874 The MMC controller on the Intel PXA is supported. To 875 enable this define CONFIG_MMC. The MMC can be 876 accessed from the boot prompt by mapping the device 877 to physical memory similar to flash. Command line is 878 enabled with CONFIG_CMD_MMC. The MMC driver also works with 879 the FAT fs. This is enabled with CONFIG_CMD_FAT. 880 881- Journaling Flash filesystem support: 882 CONFIG_JFFS2_NAND, CONFIG_JFFS2_NAND_OFF, CONFIG_JFFS2_NAND_SIZE, 883 CONFIG_JFFS2_NAND_DEV 884 Define these for a default partition on a NAND device 885 886 CFG_JFFS2_FIRST_SECTOR, 887 CFG_JFFS2_FIRST_BANK, CFG_JFFS2_NUM_BANKS 888 Define these for a default partition on a NOR device 889 890 CFG_JFFS_CUSTOM_PART 891 Define this to create an own partition. You have to provide a 892 function struct part_info* jffs2_part_info(int part_num) 893 894 If you define only one JFFS2 partition you may also want to 895 #define CFG_JFFS_SINGLE_PART 1 896 to disable the command chpart. This is the default when you 897 have not defined a custom partition 898 899- Keyboard Support: 900 CONFIG_ISA_KEYBOARD 901 902 Define this to enable standard (PC-Style) keyboard 903 support 904 905 CONFIG_I8042_KBD 906 Standard PC keyboard driver with US (is default) and 907 GERMAN key layout (switch via environment 'keymap=de') support. 908 Export function i8042_kbd_init, i8042_tstc and i8042_getc 909 for cfb_console. Supports cursor blinking. 910 911- Video support: 912 CONFIG_VIDEO 913 914 Define this to enable video support (for output to 915 video). 916 917 CONFIG_VIDEO_CT69000 918 919 Enable Chips & Technologies 69000 Video chip 920 921 CONFIG_VIDEO_SMI_LYNXEM 922 Enable Silicon Motion SMI 712/710/810 Video chip. The 923 video output is selected via environment 'videoout' 924 (1 = LCD and 2 = CRT). If videoout is undefined, CRT is 925 assumed. 926 927 For the CT69000 and SMI_LYNXEM drivers, videomode is 928 selected via environment 'videomode'. Two diferent ways 929 are possible: 930 - "videomode=num" 'num' is a standard LiLo mode numbers. 931 Following standard modes are supported (* is default): 932 933 Colors 640x480 800x600 1024x768 1152x864 1280x1024 934 -------------+--------------------------------------------- 935 8 bits | 0x301* 0x303 0x305 0x161 0x307 936 15 bits | 0x310 0x313 0x316 0x162 0x319 937 16 bits | 0x311 0x314 0x317 0x163 0x31A 938 24 bits | 0x312 0x315 0x318 ? 0x31B 939 -------------+--------------------------------------------- 940 (i.e. setenv videomode 317; saveenv; reset;) 941 942 - "videomode=bootargs" all the video parameters are parsed 943 from the bootargs. (See drivers/video/videomodes.c) 944 945 946 CONFIG_VIDEO_SED13806 947 Enable Epson SED13806 driver. This driver supports 8bpp 948 and 16bpp modes defined by CONFIG_VIDEO_SED13806_8BPP 949 or CONFIG_VIDEO_SED13806_16BPP 950 951- Keyboard Support: 952 CONFIG_KEYBOARD 953 954 Define this to enable a custom keyboard support. 955 This simply calls drv_keyboard_init() which must be 956 defined in your board-specific files. 957 The only board using this so far is RBC823. 958 959- LCD Support: CONFIG_LCD 960 961 Define this to enable LCD support (for output to LCD 962 display); also select one of the supported displays 963 by defining one of these: 964 965 CONFIG_ATMEL_LCD: 966 967 HITACHI TX09D70VM1CCA, 3.5", 240x320. 968 969 CONFIG_NEC_NL6448AC33: 970 971 NEC NL6448AC33-18. Active, color, single scan. 972 973 CONFIG_NEC_NL6448BC20 974 975 NEC NL6448BC20-08. 6.5", 640x480. 976 Active, color, single scan. 977 978 CONFIG_NEC_NL6448BC33_54 979 980 NEC NL6448BC33-54. 10.4", 640x480. 981 Active, color, single scan. 982 983 CONFIG_SHARP_16x9 984 985 Sharp 320x240. Active, color, single scan. 986 It isn't 16x9, and I am not sure what it is. 987 988 CONFIG_SHARP_LQ64D341 989 990 Sharp LQ64D341 display, 640x480. 991 Active, color, single scan. 992 993 CONFIG_HLD1045 994 995 HLD1045 display, 640x480. 996 Active, color, single scan. 997 998 CONFIG_OPTREX_BW 999 1000 Optrex CBL50840-2 NF-FW 99 22 M5 1001 or 1002 Hitachi LMG6912RPFC-00T 1003 or 1004 Hitachi SP14Q002 1005 1006 320x240. Black & white. 1007 1008 Normally display is black on white background; define 1009 CFG_WHITE_ON_BLACK to get it inverted. 1010 1011- Splash Screen Support: CONFIG_SPLASH_SCREEN 1012 1013 If this option is set, the environment is checked for 1014 a variable "splashimage". If found, the usual display 1015 of logo, copyright and system information on the LCD 1016 is suppressed and the BMP image at the address 1017 specified in "splashimage" is loaded instead. The 1018 console is redirected to the "nulldev", too. This 1019 allows for a "silent" boot where a splash screen is 1020 loaded very quickly after power-on. 1021 1022- Gzip compressed BMP image support: CONFIG_VIDEO_BMP_GZIP 1023 1024 If this option is set, additionally to standard BMP 1025 images, gzipped BMP images can be displayed via the 1026 splashscreen support or the bmp command. 1027 1028- Compression support: 1029 CONFIG_BZIP2 1030 1031 If this option is set, support for bzip2 compressed 1032 images is included. If not, only uncompressed and gzip 1033 compressed images are supported. 1034 1035 NOTE: the bzip2 algorithm requires a lot of RAM, so 1036 the malloc area (as defined by CFG_MALLOC_LEN) should 1037 be at least 4MB. 1038 1039- MII/PHY support: 1040 CONFIG_PHY_ADDR 1041 1042 The address of PHY on MII bus. 1043 1044 CONFIG_PHY_CLOCK_FREQ (ppc4xx) 1045 1046 The clock frequency of the MII bus 1047 1048 CONFIG_PHY_GIGE 1049 1050 If this option is set, support for speed/duplex 1051 detection of Gigabit PHY is included. 1052 1053 CONFIG_PHY_RESET_DELAY 1054 1055 Some PHY like Intel LXT971A need extra delay after 1056 reset before any MII register access is possible. 1057 For such PHY, set this option to the usec delay 1058 required. (minimum 300usec for LXT971A) 1059 1060 CONFIG_PHY_CMD_DELAY (ppc4xx) 1061 1062 Some PHY like Intel LXT971A need extra delay after 1063 command issued before MII status register can be read 1064 1065- Ethernet address: 1066 CONFIG_ETHADDR 1067 CONFIG_ETH2ADDR 1068 CONFIG_ETH3ADDR 1069 1070 Define a default value for ethernet address to use 1071 for the respective ethernet interface, in case this 1072 is not determined automatically. 1073 1074- IP address: 1075 CONFIG_IPADDR 1076 1077 Define a default value for the IP address to use for 1078 the default ethernet interface, in case this is not 1079 determined through e.g. bootp. 1080 1081- Server IP address: 1082 CONFIG_SERVERIP 1083 1084 Defines a default value for theIP address of a TFTP 1085 server to contact when using the "tftboot" command. 1086 1087- Multicast TFTP Mode: 1088 CONFIG_MCAST_TFTP 1089 1090 Defines whether you want to support multicast TFTP as per 1091 rfc-2090; for example to work with atftp. Lets lots of targets 1092 tftp down the same boot image concurrently. Note: the ethernet 1093 driver in use must provide a function: mcast() to join/leave a 1094 multicast group. 1095 1096 CONFIG_BOOTP_RANDOM_DELAY 1097- BOOTP Recovery Mode: 1098 CONFIG_BOOTP_RANDOM_DELAY 1099 1100 If you have many targets in a network that try to 1101 boot using BOOTP, you may want to avoid that all 1102 systems send out BOOTP requests at precisely the same 1103 moment (which would happen for instance at recovery 1104 from a power failure, when all systems will try to 1105 boot, thus flooding the BOOTP server. Defining 1106 CONFIG_BOOTP_RANDOM_DELAY causes a random delay to be 1107 inserted before sending out BOOTP requests. The 1108 following delays are inserted then: 1109 1110 1st BOOTP request: delay 0 ... 1 sec 1111 2nd BOOTP request: delay 0 ... 2 sec 1112 3rd BOOTP request: delay 0 ... 4 sec 1113 4th and following 1114 BOOTP requests: delay 0 ... 8 sec 1115 1116- DHCP Advanced Options: 1117 You can fine tune the DHCP functionality by defining 1118 CONFIG_BOOTP_* symbols: 1119 1120 CONFIG_BOOTP_SUBNETMASK 1121 CONFIG_BOOTP_GATEWAY 1122 CONFIG_BOOTP_HOSTNAME 1123 CONFIG_BOOTP_NISDOMAIN 1124 CONFIG_BOOTP_BOOTPATH 1125 CONFIG_BOOTP_BOOTFILESIZE 1126 CONFIG_BOOTP_DNS 1127 CONFIG_BOOTP_DNS2 1128 CONFIG_BOOTP_SEND_HOSTNAME 1129 CONFIG_BOOTP_NTPSERVER 1130 CONFIG_BOOTP_TIMEOFFSET 1131 CONFIG_BOOTP_VENDOREX 1132 1133 CONFIG_BOOTP_SERVERIP - TFTP server will be the serverip 1134 environment variable, not the BOOTP server. 1135 1136 CONFIG_BOOTP_DNS2 - If a DHCP client requests the DNS 1137 serverip from a DHCP server, it is possible that more 1138 than one DNS serverip is offered to the client. 1139 If CONFIG_BOOTP_DNS2 is enabled, the secondary DNS 1140 serverip will be stored in the additional environment 1141 variable "dnsip2". The first DNS serverip is always 1142 stored in the variable "dnsip", when CONFIG_BOOTP_DNS 1143 is defined. 1144 1145 CONFIG_BOOTP_SEND_HOSTNAME - Some DHCP servers are capable 1146 to do a dynamic update of a DNS server. To do this, they 1147 need the hostname of the DHCP requester. 1148 If CONFIG_BOOTP_SEND_HOSTNAME is defined, the content 1149 of the "hostname" environment variable is passed as 1150 option 12 to the DHCP server. 1151 1152 CONFIG_BOOTP_DHCP_REQUEST_DELAY 1153 1154 A 32bit value in microseconds for a delay between 1155 receiving a "DHCP Offer" and sending the "DHCP Request". 1156 This fixes a problem with certain DHCP servers that don't 1157 respond 100% of the time to a "DHCP request". E.g. On an 1158 AT91RM9200 processor running at 180MHz, this delay needed 1159 to be *at least* 15,000 usec before a Windows Server 2003 1160 DHCP server would reply 100% of the time. I recommend at 1161 least 50,000 usec to be safe. The alternative is to hope 1162 that one of the retries will be successful but note that 1163 the DHCP timeout and retry process takes a longer than 1164 this delay. 1165 1166 - CDP Options: 1167 CONFIG_CDP_DEVICE_ID 1168 1169 The device id used in CDP trigger frames. 1170 1171 CONFIG_CDP_DEVICE_ID_PREFIX 1172 1173 A two character string which is prefixed to the MAC address 1174 of the device. 1175 1176 CONFIG_CDP_PORT_ID 1177 1178 A printf format string which contains the ascii name of 1179 the port. Normally is set to "eth%d" which sets 1180 eth0 for the first ethernet, eth1 for the second etc. 1181 1182 CONFIG_CDP_CAPABILITIES 1183 1184 A 32bit integer which indicates the device capabilities; 1185 0x00000010 for a normal host which does not forwards. 1186 1187 CONFIG_CDP_VERSION 1188 1189 An ascii string containing the version of the software. 1190 1191 CONFIG_CDP_PLATFORM 1192 1193 An ascii string containing the name of the platform. 1194 1195 CONFIG_CDP_TRIGGER 1196 1197 A 32bit integer sent on the trigger. 1198 1199 CONFIG_CDP_POWER_CONSUMPTION 1200 1201 A 16bit integer containing the power consumption of the 1202 device in .1 of milliwatts. 1203 1204 CONFIG_CDP_APPLIANCE_VLAN_TYPE 1205 1206 A byte containing the id of the VLAN. 1207 1208- Status LED: CONFIG_STATUS_LED 1209 1210 Several configurations allow to display the current 1211 status using a LED. For instance, the LED will blink 1212 fast while running U-Boot code, stop blinking as 1213 soon as a reply to a BOOTP request was received, and 1214 start blinking slow once the Linux kernel is running 1215 (supported by a status LED driver in the Linux 1216 kernel). Defining CONFIG_STATUS_LED enables this 1217 feature in U-Boot. 1218 1219- CAN Support: CONFIG_CAN_DRIVER 1220 1221 Defining CONFIG_CAN_DRIVER enables CAN driver support 1222 on those systems that support this (optional) 1223 feature, like the TQM8xxL modules. 1224 1225- I2C Support: CONFIG_HARD_I2C | CONFIG_SOFT_I2C 1226 1227 These enable I2C serial bus commands. Defining either of 1228 (but not both of) CONFIG_HARD_I2C or CONFIG_SOFT_I2C will 1229 include the appropriate I2C driver for the selected cpu. 1230 1231 This will allow you to use i2c commands at the u-boot 1232 command line (as long as you set CONFIG_CMD_I2C in 1233 CONFIG_COMMANDS) and communicate with i2c based realtime 1234 clock chips. See common/cmd_i2c.c for a description of the 1235 command line interface. 1236 1237 CONFIG_I2C_CMD_TREE is a recommended option that places 1238 all I2C commands under a single 'i2c' root command. The 1239 older 'imm', 'imd', 'iprobe' etc. commands are considered 1240 deprecated and may disappear in the future. 1241 1242 CONFIG_HARD_I2C selects a hardware I2C controller. 1243 1244 CONFIG_SOFT_I2C configures u-boot to use a software (aka 1245 bit-banging) driver instead of CPM or similar hardware 1246 support for I2C. 1247 1248 There are several other quantities that must also be 1249 defined when you define CONFIG_HARD_I2C or CONFIG_SOFT_I2C. 1250 1251 In both cases you will need to define CFG_I2C_SPEED 1252 to be the frequency (in Hz) at which you wish your i2c bus 1253 to run and CFG_I2C_SLAVE to be the address of this node (ie 1254 the cpu's i2c node address). 1255 1256 Now, the u-boot i2c code for the mpc8xx (cpu/mpc8xx/i2c.c) 1257 sets the cpu up as a master node and so its address should 1258 therefore be cleared to 0 (See, eg, MPC823e User's Manual 1259 p.16-473). So, set CFG_I2C_SLAVE to 0. 1260 1261 That's all that's required for CONFIG_HARD_I2C. 1262 1263 If you use the software i2c interface (CONFIG_SOFT_I2C) 1264 then the following macros need to be defined (examples are 1265 from include/configs/lwmon.h): 1266 1267 I2C_INIT 1268 1269 (Optional). Any commands necessary to enable the I2C 1270 controller or configure ports. 1271 1272 eg: #define I2C_INIT (immr->im_cpm.cp_pbdir |= PB_SCL) 1273 1274 I2C_PORT 1275 1276 (Only for MPC8260 CPU). The I/O port to use (the code 1277 assumes both bits are on the same port). Valid values 1278 are 0..3 for ports A..D. 1279 1280 I2C_ACTIVE 1281 1282 The code necessary to make the I2C data line active 1283 (driven). If the data line is open collector, this 1284 define can be null. 1285 1286 eg: #define I2C_ACTIVE (immr->im_cpm.cp_pbdir |= PB_SDA) 1287 1288 I2C_TRISTATE 1289 1290 The code necessary to make the I2C data line tri-stated 1291 (inactive). If the data line is open collector, this 1292 define can be null. 1293 1294 eg: #define I2C_TRISTATE (immr->im_cpm.cp_pbdir &= ~PB_SDA) 1295 1296 I2C_READ 1297 1298 Code that returns TRUE if the I2C data line is high, 1299 FALSE if it is low. 1300 1301 eg: #define I2C_READ ((immr->im_cpm.cp_pbdat & PB_SDA) != 0) 1302 1303 I2C_SDA(bit) 1304 1305 If <bit> is TRUE, sets the I2C data line high. If it 1306 is FALSE, it clears it (low). 1307 1308 eg: #define I2C_SDA(bit) \ 1309 if(bit) immr->im_cpm.cp_pbdat |= PB_SDA; \ 1310 else immr->im_cpm.cp_pbdat &= ~PB_SDA 1311 1312 I2C_SCL(bit) 1313 1314 If <bit> is TRUE, sets the I2C clock line high. If it 1315 is FALSE, it clears it (low). 1316 1317 eg: #define I2C_SCL(bit) \ 1318 if(bit) immr->im_cpm.cp_pbdat |= PB_SCL; \ 1319 else immr->im_cpm.cp_pbdat &= ~PB_SCL 1320 1321 I2C_DELAY 1322 1323 This delay is invoked four times per clock cycle so this 1324 controls the rate of data transfer. The data rate thus 1325 is 1 / (I2C_DELAY * 4). Often defined to be something 1326 like: 1327 1328 #define I2C_DELAY udelay(2) 1329 1330 CFG_I2C_INIT_BOARD 1331 1332 When a board is reset during an i2c bus transfer 1333 chips might think that the current transfer is still 1334 in progress. On some boards it is possible to access 1335 the i2c SCLK line directly, either by using the 1336 processor pin as a GPIO or by having a second pin 1337 connected to the bus. If this option is defined a 1338 custom i2c_init_board() routine in boards/xxx/board.c 1339 is run early in the boot sequence. 1340 1341 CONFIG_I2CFAST (PPC405GP|PPC405EP only) 1342 1343 This option enables configuration of bi_iic_fast[] flags 1344 in u-boot bd_info structure based on u-boot environment 1345 variable "i2cfast". (see also i2cfast) 1346 1347 CONFIG_I2C_MULTI_BUS 1348 1349 This option allows the use of multiple I2C buses, each of which 1350 must have a controller. At any point in time, only one bus is 1351 active. To switch to a different bus, use the 'i2c dev' command. 1352 Note that bus numbering is zero-based. 1353 1354 CFG_I2C_NOPROBES 1355 1356 This option specifies a list of I2C devices that will be skipped 1357 when the 'i2c probe' command is issued (or 'iprobe' using the legacy 1358 command). If CONFIG_I2C_MULTI_BUS is set, specify a list of bus-device 1359 pairs. Otherwise, specify a 1D array of device addresses 1360 1361 e.g. 1362 #undef CONFIG_I2C_MULTI_BUS 1363 #define CFG_I2C_NOPROBES {0x50,0x68} 1364 1365 will skip addresses 0x50 and 0x68 on a board with one I2C bus 1366 1367 #define CONFIG_I2C_MULTI_BUS 1368 #define CFG_I2C_MULTI_NOPROBES {{0,0x50},{0,0x68},{1,0x54}} 1369 1370 will skip addresses 0x50 and 0x68 on bus 0 and address 0x54 on bus 1 1371 1372 CFG_SPD_BUS_NUM 1373 1374 If defined, then this indicates the I2C bus number for DDR SPD. 1375 If not defined, then U-Boot assumes that SPD is on I2C bus 0. 1376 1377 CFG_RTC_BUS_NUM 1378 1379 If defined, then this indicates the I2C bus number for the RTC. 1380 If not defined, then U-Boot assumes that RTC is on I2C bus 0. 1381 1382 CFG_DTT_BUS_NUM 1383 1384 If defined, then this indicates the I2C bus number for the DTT. 1385 If not defined, then U-Boot assumes that DTT is on I2C bus 0. 1386 1387 CONFIG_FSL_I2C 1388 1389 Define this option if you want to use Freescale's I2C driver in 1390 drivers/i2c/fsl_i2c.c. 1391 1392 1393- SPI Support: CONFIG_SPI 1394 1395 Enables SPI driver (so far only tested with 1396 SPI EEPROM, also an instance works with Crystal A/D and 1397 D/As on the SACSng board) 1398 1399 CONFIG_SPI_X 1400 1401 Enables extended (16-bit) SPI EEPROM addressing. 1402 (symmetrical to CONFIG_I2C_X) 1403 1404 CONFIG_SOFT_SPI 1405 1406 Enables a software (bit-bang) SPI driver rather than 1407 using hardware support. This is a general purpose 1408 driver that only requires three general I/O port pins 1409 (two outputs, one input) to function. If this is 1410 defined, the board configuration must define several 1411 SPI configuration items (port pins to use, etc). For 1412 an example, see include/configs/sacsng.h. 1413 1414 CONFIG_HARD_SPI 1415 1416 Enables a hardware SPI driver for general-purpose reads 1417 and writes. As with CONFIG_SOFT_SPI, the board configuration 1418 must define a list of chip-select function pointers. 1419 Currently supported on some MPC8xxx processors. For an 1420 example, see include/configs/mpc8349emds.h. 1421 1422 CONFIG_MXC_SPI 1423 1424 Enables the driver for the SPI controllers on i.MX and MXC 1425 SoCs. Currently only i.MX31 is supported. 1426 1427- FPGA Support: CONFIG_FPGA 1428 1429 Enables FPGA subsystem. 1430 1431 CONFIG_FPGA_<vendor> 1432 1433 Enables support for specific chip vendors. 1434 (ALTERA, XILINX) 1435 1436 CONFIG_FPGA_<family> 1437 1438 Enables support for FPGA family. 1439 (SPARTAN2, SPARTAN3, VIRTEX2, CYCLONE2, ACEX1K, ACEX) 1440 1441 CONFIG_FPGA_COUNT 1442 1443 Specify the number of FPGA devices to support. 1444 1445 CFG_FPGA_PROG_FEEDBACK 1446 1447 Enable printing of hash marks during FPGA configuration. 1448 1449 CFG_FPGA_CHECK_BUSY 1450 1451 Enable checks on FPGA configuration interface busy 1452 status by the configuration function. This option 1453 will require a board or device specific function to 1454 be written. 1455 1456 CONFIG_FPGA_DELAY 1457 1458 If defined, a function that provides delays in the FPGA 1459 configuration driver. 1460 1461 CFG_FPGA_CHECK_CTRLC 1462 Allow Control-C to interrupt FPGA configuration 1463 1464 CFG_FPGA_CHECK_ERROR 1465 1466 Check for configuration errors during FPGA bitfile 1467 loading. For example, abort during Virtex II 1468 configuration if the INIT_B line goes low (which 1469 indicated a CRC error). 1470 1471 CFG_FPGA_WAIT_INIT 1472 1473 Maximum time to wait for the INIT_B line to deassert 1474 after PROB_B has been deasserted during a Virtex II 1475 FPGA configuration sequence. The default time is 500 1476 mS. 1477 1478 CFG_FPGA_WAIT_BUSY 1479 1480 Maximum time to wait for BUSY to deassert during 1481 Virtex II FPGA configuration. The default is 5 mS. 1482 1483 CFG_FPGA_WAIT_CONFIG 1484 1485 Time to wait after FPGA configuration. The default is 1486 200 mS. 1487 1488- Configuration Management: 1489 CONFIG_IDENT_STRING 1490 1491 If defined, this string will be added to the U-Boot 1492 version information (U_BOOT_VERSION) 1493 1494- Vendor Parameter Protection: 1495 1496 U-Boot considers the values of the environment 1497 variables "serial#" (Board Serial Number) and 1498 "ethaddr" (Ethernet Address) to be parameters that 1499 are set once by the board vendor / manufacturer, and 1500 protects these variables from casual modification by 1501 the user. Once set, these variables are read-only, 1502 and write or delete attempts are rejected. You can 1503 change this behviour: 1504 1505 If CONFIG_ENV_OVERWRITE is #defined in your config 1506 file, the write protection for vendor parameters is 1507 completely disabled. Anybody can change or delete 1508 these parameters. 1509 1510 Alternatively, if you #define _both_ CONFIG_ETHADDR 1511 _and_ CONFIG_OVERWRITE_ETHADDR_ONCE, a default 1512 ethernet address is installed in the environment, 1513 which can be changed exactly ONCE by the user. [The 1514 serial# is unaffected by this, i. e. it remains 1515 read-only.] 1516 1517- Protected RAM: 1518 CONFIG_PRAM 1519 1520 Define this variable to enable the reservation of 1521 "protected RAM", i. e. RAM which is not overwritten 1522 by U-Boot. Define CONFIG_PRAM to hold the number of 1523 kB you want to reserve for pRAM. You can overwrite 1524 this default value by defining an environment 1525 variable "pram" to the number of kB you want to 1526 reserve. Note that the board info structure will 1527 still show the full amount of RAM. If pRAM is 1528 reserved, a new environment variable "mem" will 1529 automatically be defined to hold the amount of 1530 remaining RAM in a form that can be passed as boot 1531 argument to Linux, for instance like that: 1532 1533 setenv bootargs ... mem=\${mem} 1534 saveenv 1535 1536 This way you can tell Linux not to use this memory, 1537 either, which results in a memory region that will 1538 not be affected by reboots. 1539 1540 *WARNING* If your board configuration uses automatic 1541 detection of the RAM size, you must make sure that 1542 this memory test is non-destructive. So far, the 1543 following board configurations are known to be 1544 "pRAM-clean": 1545 1546 ETX094, IVMS8, IVML24, SPD8xx, TQM8xxL, 1547 HERMES, IP860, RPXlite, LWMON, LANTEC, 1548 PCU_E, FLAGADM, TQM8260 1549 1550- Error Recovery: 1551 CONFIG_PANIC_HANG 1552 1553 Define this variable to stop the system in case of a 1554 fatal error, so that you have to reset it manually. 1555 This is probably NOT a good idea for an embedded 1556 system where you want to system to reboot 1557 automatically as fast as possible, but it may be 1558 useful during development since you can try to debug 1559 the conditions that lead to the situation. 1560 1561 CONFIG_NET_RETRY_COUNT 1562 1563 This variable defines the number of retries for 1564 network operations like ARP, RARP, TFTP, or BOOTP 1565 before giving up the operation. If not defined, a 1566 default value of 5 is used. 1567 1568 CONFIG_ARP_TIMEOUT 1569 1570 Timeout waiting for an ARP reply in milliseconds. 1571 1572- Command Interpreter: 1573 CONFIG_AUTO_COMPLETE 1574 1575 Enable auto completion of commands using TAB. 1576 1577 Note that this feature has NOT been implemented yet 1578 for the "hush" shell. 1579 1580 1581 CFG_HUSH_PARSER 1582 1583 Define this variable to enable the "hush" shell (from 1584 Busybox) as command line interpreter, thus enabling 1585 powerful command line syntax like 1586 if...then...else...fi conditionals or `&&' and '||' 1587 constructs ("shell scripts"). 1588 1589 If undefined, you get the old, much simpler behaviour 1590 with a somewhat smaller memory footprint. 1591 1592 1593 CFG_PROMPT_HUSH_PS2 1594 1595 This defines the secondary prompt string, which is 1596 printed when the command interpreter needs more input 1597 to complete a command. Usually "> ". 1598 1599 Note: 1600 1601 In the current implementation, the local variables 1602 space and global environment variables space are 1603 separated. Local variables are those you define by 1604 simply typing `name=value'. To access a local 1605 variable later on, you have write `$name' or 1606 `${name}'; to execute the contents of a variable 1607 directly type `$name' at the command prompt. 1608 1609 Global environment variables are those you use 1610 setenv/printenv to work with. To run a command stored 1611 in such a variable, you need to use the run command, 1612 and you must not use the '$' sign to access them. 1613 1614 To store commands and special characters in a 1615 variable, please use double quotation marks 1616 surrounding the whole text of the variable, instead 1617 of the backslashes before semicolons and special 1618 symbols. 1619 1620- Commandline Editing and History: 1621 CONFIG_CMDLINE_EDITING 1622 1623 Enable editiong and History functions for interactive 1624 commandline input operations 1625 1626- Default Environment: 1627 CONFIG_EXTRA_ENV_SETTINGS 1628 1629 Define this to contain any number of null terminated 1630 strings (variable = value pairs) that will be part of 1631 the default environment compiled into the boot image. 1632 1633 For example, place something like this in your 1634 board's config file: 1635 1636 #define CONFIG_EXTRA_ENV_SETTINGS \ 1637 "myvar1=value1\0" \ 1638 "myvar2=value2\0" 1639 1640 Warning: This method is based on knowledge about the 1641 internal format how the environment is stored by the 1642 U-Boot code. This is NOT an official, exported 1643 interface! Although it is unlikely that this format 1644 will change soon, there is no guarantee either. 1645 You better know what you are doing here. 1646 1647 Note: overly (ab)use of the default environment is 1648 discouraged. Make sure to check other ways to preset 1649 the environment like the autoscript function or the 1650 boot command first. 1651 1652- DataFlash Support: 1653 CONFIG_HAS_DATAFLASH 1654 1655 Defining this option enables DataFlash features and 1656 allows to read/write in Dataflash via the standard 1657 commands cp, md... 1658 1659- SystemACE Support: 1660 CONFIG_SYSTEMACE 1661 1662 Adding this option adds support for Xilinx SystemACE 1663 chips attached via some sort of local bus. The address 1664 of the chip must alsh be defined in the 1665 CFG_SYSTEMACE_BASE macro. For example: 1666 1667 #define CONFIG_SYSTEMACE 1668 #define CFG_SYSTEMACE_BASE 0xf0000000 1669 1670 When SystemACE support is added, the "ace" device type 1671 becomes available to the fat commands, i.e. fatls. 1672 1673- TFTP Fixed UDP Port: 1674 CONFIG_TFTP_PORT 1675 1676 If this is defined, the environment variable tftpsrcp 1677 is used to supply the TFTP UDP source port value. 1678 If tftpsrcp isn't defined, the normal pseudo-random port 1679 number generator is used. 1680 1681 Also, the environment variable tftpdstp is used to supply 1682 the TFTP UDP destination port value. If tftpdstp isn't 1683 defined, the normal port 69 is used. 1684 1685 The purpose for tftpsrcp is to allow a TFTP server to 1686 blindly start the TFTP transfer using the pre-configured 1687 target IP address and UDP port. This has the effect of 1688 "punching through" the (Windows XP) firewall, allowing 1689 the remainder of the TFTP transfer to proceed normally. 1690 A better solution is to properly configure the firewall, 1691 but sometimes that is not allowed. 1692 1693- Show boot progress: 1694 CONFIG_SHOW_BOOT_PROGRESS 1695 1696 Defining this option allows to add some board- 1697 specific code (calling a user-provided function 1698 "show_boot_progress(int)") that enables you to show 1699 the system's boot progress on some display (for 1700 example, some LED's) on your board. At the moment, 1701 the following checkpoints are implemented: 1702 1703Legacy uImage format: 1704 1705 Arg Where When 1706 1 common/cmd_bootm.c before attempting to boot an image 1707 -1 common/cmd_bootm.c Image header has bad magic number 1708 2 common/cmd_bootm.c Image header has correct magic number 1709 -2 common/cmd_bootm.c Image header has bad checksum 1710 3 common/cmd_bootm.c Image header has correct checksum 1711 -3 common/cmd_bootm.c Image data has bad checksum 1712 4 common/cmd_bootm.c Image data has correct checksum 1713 -4 common/cmd_bootm.c Image is for unsupported architecture 1714 5 common/cmd_bootm.c Architecture check OK 1715 -5 common/cmd_bootm.c Wrong Image Type (not kernel, multi) 1716 6 common/cmd_bootm.c Image Type check OK 1717 -6 common/cmd_bootm.c gunzip uncompression error 1718 -7 common/cmd_bootm.c Unimplemented compression type 1719 7 common/cmd_bootm.c Uncompression OK 1720 8 common/cmd_bootm.c No uncompress/copy overwrite error 1721 -9 common/cmd_bootm.c Unsupported OS (not Linux, BSD, VxWorks, QNX) 1722 1723 9 common/image.c Start initial ramdisk verification 1724 -10 common/image.c Ramdisk header has bad magic number 1725 -11 common/image.c Ramdisk header has bad checksum 1726 10 common/image.c Ramdisk header is OK 1727 -12 common/image.c Ramdisk data has bad checksum 1728 11 common/image.c Ramdisk data has correct checksum 1729 12 common/image.c Ramdisk verification complete, start loading 1730 -13 common/image.c Wrong Image Type (not PPC Linux Ramdisk) 1731 13 common/image.c Start multifile image verification 1732 14 common/image.c No initial ramdisk, no multifile, continue. 1733 1734 15 lib_<arch>/bootm.c All preparation done, transferring control to OS 1735 1736 -30 lib_ppc/board.c Fatal error, hang the system 1737 -31 post/post.c POST test failed, detected by post_output_backlog() 1738 -32 post/post.c POST test failed, detected by post_run_single() 1739 1740 34 common/cmd_doc.c before loading a Image from a DOC device 1741 -35 common/cmd_doc.c Bad usage of "doc" command 1742 35 common/cmd_doc.c correct usage of "doc" command 1743 -36 common/cmd_doc.c No boot device 1744 36 common/cmd_doc.c correct boot device 1745 -37 common/cmd_doc.c Unknown Chip ID on boot device 1746 37 common/cmd_doc.c correct chip ID found, device available 1747 -38 common/cmd_doc.c Read Error on boot device 1748 38 common/cmd_doc.c reading Image header from DOC device OK 1749 -39 common/cmd_doc.c Image header has bad magic number 1750 39 common/cmd_doc.c Image header has correct magic number 1751 -40 common/cmd_doc.c Error reading Image from DOC device 1752 40 common/cmd_doc.c Image header has correct magic number 1753 41 common/cmd_ide.c before loading a Image from a IDE device 1754 -42 common/cmd_ide.c Bad usage of "ide" command 1755 42 common/cmd_ide.c correct usage of "ide" command 1756 -43 common/cmd_ide.c No boot device 1757 43 common/cmd_ide.c boot device found 1758 -44 common/cmd_ide.c Device not available 1759 44 common/cmd_ide.c Device available 1760 -45 common/cmd_ide.c wrong partition selected 1761 45 common/cmd_ide.c partition selected 1762 -46 common/cmd_ide.c Unknown partition table 1763 46 common/cmd_ide.c valid partition table found 1764 -47 common/cmd_ide.c Invalid partition type 1765 47 common/cmd_ide.c correct partition type 1766 -48 common/cmd_ide.c Error reading Image Header on boot device 1767 48 common/cmd_ide.c reading Image Header from IDE device OK 1768 -49 common/cmd_ide.c Image header has bad magic number 1769 49 common/cmd_ide.c Image header has correct magic number 1770 -50 common/cmd_ide.c Image header has bad checksum 1771 50 common/cmd_ide.c Image header has correct checksum 1772 -51 common/cmd_ide.c Error reading Image from IDE device 1773 51 common/cmd_ide.c reading Image from IDE device OK 1774 52 common/cmd_nand.c before loading a Image from a NAND device 1775 -53 common/cmd_nand.c Bad usage of "nand" command 1776 53 common/cmd_nand.c correct usage of "nand" command 1777 -54 common/cmd_nand.c No boot device 1778 54 common/cmd_nand.c boot device found 1779 -55 common/cmd_nand.c Unknown Chip ID on boot device 1780 55 common/cmd_nand.c correct chip ID found, device available 1781 -56 common/cmd_nand.c Error reading Image Header on boot device 1782 56 common/cmd_nand.c reading Image Header from NAND device OK 1783 -57 common/cmd_nand.c Image header has bad magic number 1784 57 common/cmd_nand.c Image header has correct magic number 1785 -58 common/cmd_nand.c Error reading Image from NAND device 1786 58 common/cmd_nand.c reading Image from NAND device OK 1787 1788 -60 common/env_common.c Environment has a bad CRC, using default 1789 1790 64 net/eth.c starting with Ethernetconfiguration. 1791 -64 net/eth.c no Ethernet found. 1792 65 net/eth.c Ethernet found. 1793 1794 -80 common/cmd_net.c usage wrong 1795 80 common/cmd_net.c before calling NetLoop() 1796 -81 common/cmd_net.c some error in NetLoop() occured 1797 81 common/cmd_net.c NetLoop() back without error 1798 -82 common/cmd_net.c size == 0 (File with size 0 loaded) 1799 82 common/cmd_net.c trying automatic boot 1800 83 common/cmd_net.c running autoscript 1801 -83 common/cmd_net.c some error in automatic boot or autoscript 1802 84 common/cmd_net.c end without errors 1803 1804FIT uImage format: 1805 1806 Arg Where When 1807 100 common/cmd_bootm.c Kernel FIT Image has correct format 1808 -100 common/cmd_bootm.c Kernel FIT Image has incorrect format 1809 101 common/cmd_bootm.c No Kernel subimage unit name, using configuration 1810 -101 common/cmd_bootm.c Can't get configuration for kernel subimage 1811 102 common/cmd_bootm.c Kernel unit name specified 1812 -103 common/cmd_bootm.c Can't get kernel subimage node offset 1813 103 common/cmd_bootm.c Found configuration node 1814 104 common/cmd_bootm.c Got kernel subimage node offset 1815 -104 common/cmd_bootm.c Kernel subimage hash verification failed 1816 105 common/cmd_bootm.c Kernel subimage hash verification OK 1817 -105 common/cmd_bootm.c Kernel subimage is for unsupported architecture 1818 106 common/cmd_bootm.c Architecture check OK 1819 -106 common/cmd_bootm.c Kernel subimage has wrong typea 1820 107 common/cmd_bootm.c Kernel subimge type OK 1821 -107 common/cmd_bootm.c Can't get kernel subimage data/size 1822 108 common/cmd_bootm.c Got kernel subimage data/size 1823 -108 common/cmd_bootm.c Wrong image type (not legacy, FIT) 1824 -109 common/cmd_bootm.c Can't get kernel subimage type 1825 -110 common/cmd_bootm.c Can't get kernel subimage comp 1826 -111 common/cmd_bootm.c Can't get kernel subimage os 1827 -112 common/cmd_bootm.c Can't get kernel subimage load address 1828 -113 common/cmd_bootm.c Image uncompress/copy overwrite error 1829 1830 120 common/image.c Start initial ramdisk verification 1831 -120 common/image.c Ramdisk FIT image has incorrect format 1832 121 common/image.c Ramdisk FIT image has correct format 1833 122 common/image.c No Ramdisk subimage unit name, using configuration 1834 -122 common/image.c Can't get configuration for ramdisk subimage 1835 123 common/image.c Ramdisk unit name specified 1836 -124 common/image.c Can't get ramdisk subimage node offset 1837 125 common/image.c Got ramdisk subimage node offset 1838 -125 common/image.c Ramdisk subimage hash verification failed 1839 126 common/image.c Ramdisk subimage hash verification OK 1840 -126 common/image.c Ramdisk subimage for unsupported architecture 1841 127 common/image.c Architecture check OK 1842 -127 common/image.c Can't get ramdisk subimage data/size 1843 128 common/image.c Got ramdisk subimage data/size 1844 129 common/image.c Can't get ramdisk load address 1845 -129 common/image.c Got ramdisk load address 1846 1847 -130 common/cmd_doc.c Icorrect FIT image format 1848 131 common/cmd_doc.c FIT image format OK 1849 1850 -140 common/cmd_ide.c Icorrect FIT image format 1851 141 common/cmd_ide.c FIT image format OK 1852 1853 -150 common/cmd_nand.c Icorrect FIT image format 1854 151 common/cmd_nand.c FIT image format OK 1855 1856 1857Modem Support: 1858-------------- 1859 1860[so far only for SMDK2400 and TRAB boards] 1861 1862- Modem support endable: 1863 CONFIG_MODEM_SUPPORT 1864 1865- RTS/CTS Flow control enable: 1866 CONFIG_HWFLOW 1867 1868- Modem debug support: 1869 CONFIG_MODEM_SUPPORT_DEBUG 1870 1871 Enables debugging stuff (char screen[1024], dbg()) 1872 for modem support. Useful only with BDI2000. 1873 1874- Interrupt support (PPC): 1875 1876 There are common interrupt_init() and timer_interrupt() 1877 for all PPC archs. interrupt_init() calls interrupt_init_cpu() 1878 for cpu specific initialization. interrupt_init_cpu() 1879 should set decrementer_count to appropriate value. If 1880 cpu resets decrementer automatically after interrupt 1881 (ppc4xx) it should set decrementer_count to zero. 1882 timer_interrupt() calls timer_interrupt_cpu() for cpu 1883 specific handling. If board has watchdog / status_led 1884 / other_activity_monitor it works automatically from 1885 general timer_interrupt(). 1886 1887- General: 1888 1889 In the target system modem support is enabled when a 1890 specific key (key combination) is pressed during 1891 power-on. Otherwise U-Boot will boot normally 1892 (autoboot). The key_pressed() fuction is called from 1893 board_init(). Currently key_pressed() is a dummy 1894 function, returning 1 and thus enabling modem 1895 initialization. 1896 1897 If there are no modem init strings in the 1898 environment, U-Boot proceed to autoboot; the 1899 previous output (banner, info printfs) will be 1900 supressed, though. 1901 1902 See also: doc/README.Modem 1903 1904 1905Configuration Settings: 1906----------------------- 1907 1908- CFG_LONGHELP: Defined when you want long help messages included; 1909 undefine this when you're short of memory. 1910 1911- CFG_PROMPT: This is what U-Boot prints on the console to 1912 prompt for user input. 1913 1914- CFG_CBSIZE: Buffer size for input from the Console 1915 1916- CFG_PBSIZE: Buffer size for Console output 1917 1918- CFG_MAXARGS: max. Number of arguments accepted for monitor commands 1919 1920- CFG_BARGSIZE: Buffer size for Boot Arguments which are passed to 1921 the application (usually a Linux kernel) when it is 1922 booted 1923 1924- CFG_BAUDRATE_TABLE: 1925 List of legal baudrate settings for this board. 1926 1927- CFG_CONSOLE_INFO_QUIET 1928 Suppress display of console information at boot. 1929 1930- CFG_CONSOLE_IS_IN_ENV 1931 If the board specific function 1932 extern int overwrite_console (void); 1933 returns 1, the stdin, stderr and stdout are switched to the 1934 serial port, else the settings in the environment are used. 1935 1936- CFG_CONSOLE_OVERWRITE_ROUTINE 1937 Enable the call to overwrite_console(). 1938 1939- CFG_CONSOLE_ENV_OVERWRITE 1940 Enable overwrite of previous console environment settings. 1941 1942- CFG_MEMTEST_START, CFG_MEMTEST_END: 1943 Begin and End addresses of the area used by the 1944 simple memory test. 1945 1946- CFG_ALT_MEMTEST: 1947 Enable an alternate, more extensive memory test. 1948 1949- CFG_MEMTEST_SCRATCH: 1950 Scratch address used by the alternate memory test 1951 You only need to set this if address zero isn't writeable 1952 1953- CFG_MEM_TOP_HIDE (PPC only): 1954 If CFG_MEM_TOP_HIDE is defined in the board config header, 1955 this specified memory area will get subtracted from the top 1956 (end) of ram and won't get "touched" at all by U-Boot. By 1957 fixing up gd->ram_size the Linux kernel should gets passed 1958 the now "corrected" memory size and won't touch it either. 1959 This should work for arch/ppc and arch/powerpc. Only Linux 1960 board ports in arch/powerpc with bootwrapper support that 1961 recalculate the memory size from the SDRAM controller setup 1962 will have to get fixed in Linux additionally. 1963 1964 This option can be used as a workaround for the 440EPx/GRx 1965 CHIP 11 errata where the last 256 bytes in SDRAM shouldn't 1966 be touched. 1967 1968 WARNING: Please make sure that this value is a multiple of 1969 the Linux page size (normally 4k). If this is not the case, 1970 then the end address of the Linux memory will be located at a 1971 non page size aligned address and this could cause major 1972 problems. 1973 1974- CFG_TFTP_LOADADDR: 1975 Default load address for network file downloads 1976 1977- CFG_LOADS_BAUD_CHANGE: 1978 Enable temporary baudrate change while serial download 1979 1980- CFG_SDRAM_BASE: 1981 Physical start address of SDRAM. _Must_ be 0 here. 1982 1983- CFG_MBIO_BASE: 1984 Physical start address of Motherboard I/O (if using a 1985 Cogent motherboard) 1986 1987- CFG_FLASH_BASE: 1988 Physical start address of Flash memory. 1989 1990- CFG_MONITOR_BASE: 1991 Physical start address of boot monitor code (set by 1992 make config files to be same as the text base address 1993 (TEXT_BASE) used when linking) - same as 1994 CFG_FLASH_BASE when booting from flash. 1995 1996- CFG_MONITOR_LEN: 1997 Size of memory reserved for monitor code, used to 1998 determine _at_compile_time_ (!) if the environment is 1999 embedded within the U-Boot image, or in a separate 2000 flash sector. 2001 2002- CFG_MALLOC_LEN: 2003 Size of DRAM reserved for malloc() use. 2004 2005- CFG_BOOTM_LEN: 2006 Normally compressed uImages are limited to an 2007 uncompressed size of 8 MBytes. If this is not enough, 2008 you can define CFG_BOOTM_LEN in your board config file 2009 to adjust this setting to your needs. 2010 2011- CFG_BOOTMAPSZ: 2012 Maximum size of memory mapped by the startup code of 2013 the Linux kernel; all data that must be processed by 2014 the Linux kernel (bd_info, boot arguments, FDT blob if 2015 used) must be put below this limit, unless "bootm_low" 2016 enviroment variable is defined and non-zero. In such case 2017 all data for the Linux kernel must be between "bootm_low" 2018 and "bootm_low" + CFG_BOOTMAPSZ. 2019 2020- CFG_MAX_FLASH_BANKS: 2021 Max number of Flash memory banks 2022 2023- CFG_MAX_FLASH_SECT: 2024 Max number of sectors on a Flash chip 2025 2026- CFG_FLASH_ERASE_TOUT: 2027 Timeout for Flash erase operations (in ms) 2028 2029- CFG_FLASH_WRITE_TOUT: 2030 Timeout for Flash write operations (in ms) 2031 2032- CFG_FLASH_LOCK_TOUT 2033 Timeout for Flash set sector lock bit operation (in ms) 2034 2035- CFG_FLASH_UNLOCK_TOUT 2036 Timeout for Flash clear lock bits operation (in ms) 2037 2038- CFG_FLASH_PROTECTION 2039 If defined, hardware flash sectors protection is used 2040 instead of U-Boot software protection. 2041 2042- CFG_DIRECT_FLASH_TFTP: 2043 2044 Enable TFTP transfers directly to flash memory; 2045 without this option such a download has to be 2046 performed in two steps: (1) download to RAM, and (2) 2047 copy from RAM to flash. 2048 2049 The two-step approach is usually more reliable, since 2050 you can check if the download worked before you erase 2051 the flash, but in some situations (when sytem RAM is 2052 too limited to allow for a tempory copy of the 2053 downloaded image) this option may be very useful. 2054 2055- CFG_FLASH_CFI: 2056 Define if the flash driver uses extra elements in the 2057 common flash structure for storing flash geometry. 2058 2059- CFG_FLASH_CFI_DRIVER 2060 This option also enables the building of the cfi_flash driver 2061 in the drivers directory 2062 2063- CFG_FLASH_USE_BUFFER_WRITE 2064 Use buffered writes to flash. 2065 2066- CONFIG_FLASH_SPANSION_S29WS_N 2067 s29ws-n MirrorBit flash has non-standard addresses for buffered 2068 write commands. 2069 2070- CFG_FLASH_QUIET_TEST 2071 If this option is defined, the common CFI flash doesn't 2072 print it's warning upon not recognized FLASH banks. This 2073 is useful, if some of the configured banks are only 2074 optionally available. 2075 2076- CONFIG_FLASH_SHOW_PROGRESS 2077 If defined (must be an integer), print out countdown 2078 digits and dots. Recommended value: 45 (9..1) for 80 2079 column displays, 15 (3..1) for 40 column displays. 2080 2081- CFG_RX_ETH_BUFFER: 2082 Defines the number of ethernet receive buffers. On some 2083 ethernet controllers it is recommended to set this value 2084 to 8 or even higher (EEPRO100 or 405 EMAC), since all 2085 buffers can be full shortly after enabling the interface 2086 on high ethernet traffic. 2087 Defaults to 4 if not defined. 2088 2089The following definitions that deal with the placement and management 2090of environment data (variable area); in general, we support the 2091following configurations: 2092 2093- CFG_ENV_IS_IN_FLASH: 2094 2095 Define this if the environment is in flash memory. 2096 2097 a) The environment occupies one whole flash sector, which is 2098 "embedded" in the text segment with the U-Boot code. This 2099 happens usually with "bottom boot sector" or "top boot 2100 sector" type flash chips, which have several smaller 2101 sectors at the start or the end. For instance, such a 2102 layout can have sector sizes of 8, 2x4, 16, Nx32 kB. In 2103 such a case you would place the environment in one of the 2104 4 kB sectors - with U-Boot code before and after it. With 2105 "top boot sector" type flash chips, you would put the 2106 environment in one of the last sectors, leaving a gap 2107 between U-Boot and the environment. 2108 2109 - CFG_ENV_OFFSET: 2110 2111 Offset of environment data (variable area) to the 2112 beginning of flash memory; for instance, with bottom boot 2113 type flash chips the second sector can be used: the offset 2114 for this sector is given here. 2115 2116 CFG_ENV_OFFSET is used relative to CFG_FLASH_BASE. 2117 2118 - CFG_ENV_ADDR: 2119 2120 This is just another way to specify the start address of 2121 the flash sector containing the environment (instead of 2122 CFG_ENV_OFFSET). 2123 2124 - CFG_ENV_SECT_SIZE: 2125 2126 Size of the sector containing the environment. 2127 2128 2129 b) Sometimes flash chips have few, equal sized, BIG sectors. 2130 In such a case you don't want to spend a whole sector for 2131 the environment. 2132 2133 - CFG_ENV_SIZE: 2134 2135 If you use this in combination with CFG_ENV_IS_IN_FLASH 2136 and CFG_ENV_SECT_SIZE, you can specify to use only a part 2137 of this flash sector for the environment. This saves 2138 memory for the RAM copy of the environment. 2139 2140 It may also save flash memory if you decide to use this 2141 when your environment is "embedded" within U-Boot code, 2142 since then the remainder of the flash sector could be used 2143 for U-Boot code. It should be pointed out that this is 2144 STRONGLY DISCOURAGED from a robustness point of view: 2145 updating the environment in flash makes it always 2146 necessary to erase the WHOLE sector. If something goes 2147 wrong before the contents has been restored from a copy in 2148 RAM, your target system will be dead. 2149 2150 - CFG_ENV_ADDR_REDUND 2151 CFG_ENV_SIZE_REDUND 2152 2153 These settings describe a second storage area used to hold 2154 a redundand copy of the environment data, so that there is 2155 a valid backup copy in case there is a power failure during 2156 a "saveenv" operation. 2157 2158BE CAREFUL! Any changes to the flash layout, and some changes to the 2159source code will make it necessary to adapt <board>/u-boot.lds* 2160accordingly! 2161 2162 2163- CFG_ENV_IS_IN_NVRAM: 2164 2165 Define this if you have some non-volatile memory device 2166 (NVRAM, battery buffered SRAM) which you want to use for the 2167 environment. 2168 2169 - CFG_ENV_ADDR: 2170 - CFG_ENV_SIZE: 2171 2172 These two #defines are used to determin the memory area you 2173 want to use for environment. It is assumed that this memory 2174 can just be read and written to, without any special 2175 provision. 2176 2177BE CAREFUL! The first access to the environment happens quite early 2178in U-Boot initalization (when we try to get the setting of for the 2179console baudrate). You *MUST* have mappend your NVRAM area then, or 2180U-Boot will hang. 2181 2182Please note that even with NVRAM we still use a copy of the 2183environment in RAM: we could work on NVRAM directly, but we want to 2184keep settings there always unmodified except somebody uses "saveenv" 2185to save the current settings. 2186 2187 2188- CFG_ENV_IS_IN_EEPROM: 2189 2190 Use this if you have an EEPROM or similar serial access 2191 device and a driver for it. 2192 2193 - CFG_ENV_OFFSET: 2194 - CFG_ENV_SIZE: 2195 2196 These two #defines specify the offset and size of the 2197 environment area within the total memory of your EEPROM. 2198 2199 - CFG_I2C_EEPROM_ADDR: 2200 If defined, specified the chip address of the EEPROM device. 2201 The default address is zero. 2202 2203 - CFG_EEPROM_PAGE_WRITE_BITS: 2204 If defined, the number of bits used to address bytes in a 2205 single page in the EEPROM device. A 64 byte page, for example 2206 would require six bits. 2207 2208 - CFG_EEPROM_PAGE_WRITE_DELAY_MS: 2209 If defined, the number of milliseconds to delay between 2210 page writes. The default is zero milliseconds. 2211 2212 - CFG_I2C_EEPROM_ADDR_LEN: 2213 The length in bytes of the EEPROM memory array address. Note 2214 that this is NOT the chip address length! 2215 2216 - CFG_I2C_EEPROM_ADDR_OVERFLOW: 2217 EEPROM chips that implement "address overflow" are ones 2218 like Catalyst 24WC04/08/16 which has 9/10/11 bits of 2219 address and the extra bits end up in the "chip address" bit 2220 slots. This makes a 24WC08 (1Kbyte) chip look like four 256 2221 byte chips. 2222 2223 Note that we consider the length of the address field to 2224 still be one byte because the extra address bits are hidden 2225 in the chip address. 2226 2227 - CFG_EEPROM_SIZE: 2228 The size in bytes of the EEPROM device. 2229 2230 2231- CFG_ENV_IS_IN_DATAFLASH: 2232 2233 Define this if you have a DataFlash memory device which you 2234 want to use for the environment. 2235 2236 - CFG_ENV_OFFSET: 2237 - CFG_ENV_ADDR: 2238 - CFG_ENV_SIZE: 2239 2240 These three #defines specify the offset and size of the 2241 environment area within the total memory of your DataFlash placed 2242 at the specified address. 2243 2244- CFG_ENV_IS_IN_NAND: 2245 2246 Define this if you have a NAND device which you want to use 2247 for the environment. 2248 2249 - CFG_ENV_OFFSET: 2250 - CFG_ENV_SIZE: 2251 2252 These two #defines specify the offset and size of the environment 2253 area within the first NAND device. 2254 2255 - CFG_ENV_OFFSET_REDUND 2256 2257 This setting describes a second storage area of CFG_ENV_SIZE 2258 size used to hold a redundant copy of the environment data, 2259 so that there is a valid backup copy in case there is a 2260 power failure during a "saveenv" operation. 2261 2262 Note: CFG_ENV_OFFSET and CFG_ENV_OFFSET_REDUND must be aligned 2263 to a block boundary, and CFG_ENV_SIZE must be a multiple of 2264 the NAND devices block size. 2265 2266- CFG_SPI_INIT_OFFSET 2267 2268 Defines offset to the initial SPI buffer area in DPRAM. The 2269 area is used at an early stage (ROM part) if the environment 2270 is configured to reside in the SPI EEPROM: We need a 520 byte 2271 scratch DPRAM area. It is used between the two initialization 2272 calls (spi_init_f() and spi_init_r()). A value of 0xB00 seems 2273 to be a good choice since it makes it far enough from the 2274 start of the data area as well as from the stack pointer. 2275 2276Please note that the environment is read-only until the monitor 2277has been relocated to RAM and a RAM copy of the environment has been 2278created; also, when using EEPROM you will have to use getenv_r() 2279until then to read environment variables. 2280 2281The environment is protected by a CRC32 checksum. Before the monitor 2282is relocated into RAM, as a result of a bad CRC you will be working 2283with the compiled-in default environment - *silently*!!! [This is 2284necessary, because the first environment variable we need is the 2285"baudrate" setting for the console - if we have a bad CRC, we don't 2286have any device yet where we could complain.] 2287 2288Note: once the monitor has been relocated, then it will complain if 2289the default environment is used; a new CRC is computed as soon as you 2290use the "saveenv" command to store a valid environment. 2291 2292- CFG_FAULT_ECHO_LINK_DOWN: 2293 Echo the inverted Ethernet link state to the fault LED. 2294 2295 Note: If this option is active, then CFG_FAULT_MII_ADDR 2296 also needs to be defined. 2297 2298- CFG_FAULT_MII_ADDR: 2299 MII address of the PHY to check for the Ethernet link state. 2300 2301- CFG_64BIT_VSPRINTF: 2302 Makes vsprintf (and all *printf functions) support printing 2303 of 64bit values by using the L quantifier 2304 2305- CFG_64BIT_STRTOUL: 2306 Adds simple_strtoull that returns a 64bit value 2307 2308Low Level (hardware related) configuration options: 2309--------------------------------------------------- 2310 2311- CFG_CACHELINE_SIZE: 2312 Cache Line Size of the CPU. 2313 2314- CFG_DEFAULT_IMMR: 2315 Default address of the IMMR after system reset. 2316 2317 Needed on some 8260 systems (MPC8260ADS, PQ2FADS-ZU, 2318 and RPXsuper) to be able to adjust the position of 2319 the IMMR register after a reset. 2320 2321- Floppy Disk Support: 2322 CFG_FDC_DRIVE_NUMBER 2323 2324 the default drive number (default value 0) 2325 2326 CFG_ISA_IO_STRIDE 2327 2328 defines the spacing between fdc chipset registers 2329 (default value 1) 2330 2331 CFG_ISA_IO_OFFSET 2332 2333 defines the offset of register from address. It 2334 depends on which part of the data bus is connected to 2335 the fdc chipset. (default value 0) 2336 2337 If CFG_ISA_IO_STRIDE CFG_ISA_IO_OFFSET and 2338 CFG_FDC_DRIVE_NUMBER are undefined, they take their 2339 default value. 2340 2341 if CFG_FDC_HW_INIT is defined, then the function 2342 fdc_hw_init() is called at the beginning of the FDC 2343 setup. fdc_hw_init() must be provided by the board 2344 source code. It is used to make hardware dependant 2345 initializations. 2346 2347- CFG_IMMR: Physical address of the Internal Memory. 2348 DO NOT CHANGE unless you know exactly what you're 2349 doing! (11-4) [MPC8xx/82xx systems only] 2350 2351- CFG_INIT_RAM_ADDR: 2352 2353 Start address of memory area that can be used for 2354 initial data and stack; please note that this must be 2355 writable memory that is working WITHOUT special 2356 initialization, i. e. you CANNOT use normal RAM which 2357 will become available only after programming the 2358 memory controller and running certain initialization 2359 sequences. 2360 2361 U-Boot uses the following memory types: 2362 - MPC8xx and MPC8260: IMMR (internal memory of the CPU) 2363 - MPC824X: data cache 2364 - PPC4xx: data cache 2365 2366- CFG_GBL_DATA_OFFSET: 2367 2368 Offset of the initial data structure in the memory 2369 area defined by CFG_INIT_RAM_ADDR. Usually 2370 CFG_GBL_DATA_OFFSET is chosen such that the initial 2371 data is located at the end of the available space 2372 (sometimes written as (CFG_INIT_RAM_END - 2373 CFG_INIT_DATA_SIZE), and the initial stack is just 2374 below that area (growing from (CFG_INIT_RAM_ADDR + 2375 CFG_GBL_DATA_OFFSET) downward. 2376 2377 Note: 2378 On the MPC824X (or other systems that use the data 2379 cache for initial memory) the address chosen for 2380 CFG_INIT_RAM_ADDR is basically arbitrary - it must 2381 point to an otherwise UNUSED address space between 2382 the top of RAM and the start of the PCI space. 2383 2384- CFG_SIUMCR: SIU Module Configuration (11-6) 2385 2386- CFG_SYPCR: System Protection Control (11-9) 2387 2388- CFG_TBSCR: Time Base Status and Control (11-26) 2389 2390- CFG_PISCR: Periodic Interrupt Status and Control (11-31) 2391 2392- CFG_PLPRCR: PLL, Low-Power, and Reset Control Register (15-30) 2393 2394- CFG_SCCR: System Clock and reset Control Register (15-27) 2395 2396- CFG_OR_TIMING_SDRAM: 2397 SDRAM timing 2398 2399- CFG_MAMR_PTA: 2400 periodic timer for refresh 2401 2402- CFG_DER: Debug Event Register (37-47) 2403 2404- FLASH_BASE0_PRELIM, FLASH_BASE1_PRELIM, CFG_REMAP_OR_AM, 2405 CFG_PRELIM_OR_AM, CFG_OR_TIMING_FLASH, CFG_OR0_REMAP, 2406 CFG_OR0_PRELIM, CFG_BR0_PRELIM, CFG_OR1_REMAP, CFG_OR1_PRELIM, 2407 CFG_BR1_PRELIM: 2408 Memory Controller Definitions: BR0/1 and OR0/1 (FLASH) 2409 2410- SDRAM_BASE2_PRELIM, SDRAM_BASE3_PRELIM, SDRAM_MAX_SIZE, 2411 CFG_OR_TIMING_SDRAM, CFG_OR2_PRELIM, CFG_BR2_PRELIM, 2412 CFG_OR3_PRELIM, CFG_BR3_PRELIM: 2413 Memory Controller Definitions: BR2/3 and OR2/3 (SDRAM) 2414 2415- CFG_MAMR_PTA, CFG_MPTPR_2BK_4K, CFG_MPTPR_1BK_4K, CFG_MPTPR_2BK_8K, 2416 CFG_MPTPR_1BK_8K, CFG_MAMR_8COL, CFG_MAMR_9COL: 2417 Machine Mode Register and Memory Periodic Timer 2418 Prescaler definitions (SDRAM timing) 2419 2420- CFG_I2C_UCODE_PATCH, CFG_I2C_DPMEM_OFFSET [0x1FC0]: 2421 enable I2C microcode relocation patch (MPC8xx); 2422 define relocation offset in DPRAM [DSP2] 2423 2424- CFG_SMC_UCODE_PATCH, CFG_SMC_DPMEM_OFFSET [0x1FC0]: 2425 enable SMC microcode relocation patch (MPC8xx); 2426 define relocation offset in DPRAM [SMC1] 2427 2428- CFG_SPI_UCODE_PATCH, CFG_SPI_DPMEM_OFFSET [0x1FC0]: 2429 enable SPI microcode relocation patch (MPC8xx); 2430 define relocation offset in DPRAM [SCC4] 2431 2432- CFG_USE_OSCCLK: 2433 Use OSCM clock mode on MBX8xx board. Be careful, 2434 wrong setting might damage your board. Read 2435 doc/README.MBX before setting this variable! 2436 2437- CFG_CPM_POST_WORD_ADDR: (MPC8xx, MPC8260 only) 2438 Offset of the bootmode word in DPRAM used by post 2439 (Power On Self Tests). This definition overrides 2440 #define'd default value in commproc.h resp. 2441 cpm_8260.h. 2442 2443- CFG_PCI_SLV_MEM_LOCAL, CFG_PCI_SLV_MEM_BUS, CFG_PICMR0_MASK_ATTRIB, 2444 CFG_PCI_MSTR0_LOCAL, CFG_PCIMSK0_MASK, CFG_PCI_MSTR1_LOCAL, 2445 CFG_PCIMSK1_MASK, CFG_PCI_MSTR_MEM_LOCAL, CFG_PCI_MSTR_MEM_BUS, 2446 CFG_CPU_PCI_MEM_START, CFG_PCI_MSTR_MEM_SIZE, CFG_POCMR0_MASK_ATTRIB, 2447 CFG_PCI_MSTR_MEMIO_LOCAL, CFG_PCI_MSTR_MEMIO_BUS, CPU_PCI_MEMIO_START, 2448 CFG_PCI_MSTR_MEMIO_SIZE, CFG_POCMR1_MASK_ATTRIB, CFG_PCI_MSTR_IO_LOCAL, 2449 CFG_PCI_MSTR_IO_BUS, CFG_CPU_PCI_IO_START, CFG_PCI_MSTR_IO_SIZE, 2450 CFG_POCMR2_MASK_ATTRIB: (MPC826x only) 2451 Overrides the default PCI memory map in cpu/mpc8260/pci.c if set. 2452 2453- CONFIG_SPD_EEPROM 2454 Get DDR timing information from an I2C EEPROM. Common 2455 with pluggable memory modules such as SODIMMs 2456 2457 SPD_EEPROM_ADDRESS 2458 I2C address of the SPD EEPROM 2459 2460- CFG_SPD_BUS_NUM 2461 If SPD EEPROM is on an I2C bus other than the first 2462 one, specify here. Note that the value must resolve 2463 to something your driver can deal with. 2464 2465- CFG_83XX_DDR_USES_CS0 2466 Only for 83xx systems. If specified, then DDR should 2467 be configured using CS0 and CS1 instead of CS2 and CS3. 2468 2469- CFG_83XX_DDR_USES_CS0 2470 Only for 83xx systems. If specified, then DDR should 2471 be configured using CS0 and CS1 instead of CS2 and CS3. 2472 2473- CONFIG_ETHER_ON_FEC[12] 2474 Define to enable FEC[12] on a 8xx series processor. 2475 2476- CONFIG_FEC[12]_PHY 2477 Define to the hardcoded PHY address which corresponds 2478 to the given FEC; i. e. 2479 #define CONFIG_FEC1_PHY 4 2480 means that the PHY with address 4 is connected to FEC1 2481 2482 When set to -1, means to probe for first available. 2483 2484- CONFIG_FEC[12]_PHY_NORXERR 2485 The PHY does not have a RXERR line (RMII only). 2486 (so program the FEC to ignore it). 2487 2488- CONFIG_RMII 2489 Enable RMII mode for all FECs. 2490 Note that this is a global option, we can't 2491 have one FEC in standard MII mode and another in RMII mode. 2492 2493- CONFIG_CRC32_VERIFY 2494 Add a verify option to the crc32 command. 2495 The syntax is: 2496 2497 => crc32 -v <address> <count> <crc32> 2498 2499 Where address/count indicate a memory area 2500 and crc32 is the correct crc32 which the 2501 area should have. 2502 2503- CONFIG_LOOPW 2504 Add the "loopw" memory command. This only takes effect if 2505 the memory commands are activated globally (CONFIG_CMD_MEM). 2506 2507- CONFIG_MX_CYCLIC 2508 Add the "mdc" and "mwc" memory commands. These are cyclic 2509 "md/mw" commands. 2510 Examples: 2511 2512 => mdc.b 10 4 500 2513 This command will print 4 bytes (10,11,12,13) each 500 ms. 2514 2515 => mwc.l 100 12345678 10 2516 This command will write 12345678 to address 100 all 10 ms. 2517 2518 This only takes effect if the memory commands are activated 2519 globally (CONFIG_CMD_MEM). 2520 2521- CONFIG_SKIP_LOWLEVEL_INIT 2522- CONFIG_SKIP_RELOCATE_UBOOT 2523 2524 [ARM only] If these variables are defined, then 2525 certain low level initializations (like setting up 2526 the memory controller) are omitted and/or U-Boot does 2527 not relocate itself into RAM. 2528 Normally these variables MUST NOT be defined. The 2529 only exception is when U-Boot is loaded (to RAM) by 2530 some other boot loader or by a debugger which 2531 performs these intializations itself. 2532 2533 2534Building the Software: 2535====================== 2536 2537Building U-Boot has been tested in several native build environments 2538and in many different cross environments. Of course we cannot support 2539all possibly existing versions of cross development tools in all 2540(potentially obsolete) versions. In case of tool chain problems we 2541recommend to use the ELDK (see http://www.denx.de/wiki/DULG/ELDK) 2542which is extensively used to build and test U-Boot. 2543 2544If you are not using a native environment, it is assumed that you 2545have GNU cross compiling tools available in your path. In this case, 2546you must set the environment variable CROSS_COMPILE in your shell. 2547Note that no changes to the Makefile or any other source files are 2548necessary. For example using the ELDK on a 4xx CPU, please enter: 2549 2550 $ CROSS_COMPILE=ppc_4xx- 2551 $ export CROSS_COMPILE 2552 2553U-Boot is intended to be simple to build. After installing the 2554sources you must configure U-Boot for one specific board type. This 2555is done by typing: 2556 2557 make NAME_config 2558 2559where "NAME_config" is the name of one of the existing configu- 2560rations; see the main Makefile for supported names. 2561 2562Note: for some board special configuration names may exist; check if 2563 additional information is available from the board vendor; for 2564 instance, the TQM823L systems are available without (standard) 2565 or with LCD support. You can select such additional "features" 2566 when chosing the configuration, i. e. 2567 2568 make TQM823L_config 2569 - will configure for a plain TQM823L, i. e. no LCD support 2570 2571 make TQM823L_LCD_config 2572 - will configure for a TQM823L with U-Boot console on LCD 2573 2574 etc. 2575 2576 2577Finally, type "make all", and you should get some working U-Boot 2578images ready for download to / installation on your system: 2579 2580- "u-boot.bin" is a raw binary image 2581- "u-boot" is an image in ELF binary format 2582- "u-boot.srec" is in Motorola S-Record format 2583 2584By default the build is performed locally and the objects are saved 2585in the source directory. One of the two methods can be used to change 2586this behavior and build U-Boot to some external directory: 2587 25881. Add O= to the make command line invocations: 2589 2590 make O=/tmp/build distclean 2591 make O=/tmp/build NAME_config 2592 make O=/tmp/build all 2593 25942. Set environment variable BUILD_DIR to point to the desired location: 2595 2596 export BUILD_DIR=/tmp/build 2597 make distclean 2598 make NAME_config 2599 make all 2600 2601Note that the command line "O=" setting overrides the BUILD_DIR environment 2602variable. 2603 2604 2605Please be aware that the Makefiles assume you are using GNU make, so 2606for instance on NetBSD you might need to use "gmake" instead of 2607native "make". 2608 2609 2610If the system board that you have is not listed, then you will need 2611to port U-Boot to your hardware platform. To do this, follow these 2612steps: 2613 26141. Add a new configuration option for your board to the toplevel 2615 "Makefile" and to the "MAKEALL" script, using the existing 2616 entries as examples. Note that here and at many other places 2617 boards and other names are listed in alphabetical sort order. Please 2618 keep this order. 26192. Create a new directory to hold your board specific code. Add any 2620 files you need. In your board directory, you will need at least 2621 the "Makefile", a "<board>.c", "flash.c" and "u-boot.lds". 26223. Create a new configuration file "include/configs/<board>.h" for 2623 your board 26243. If you're porting U-Boot to a new CPU, then also create a new 2625 directory to hold your CPU specific code. Add any files you need. 26264. Run "make <board>_config" with your new name. 26275. Type "make", and you should get a working "u-boot.srec" file 2628 to be installed on your target system. 26296. Debug and solve any problems that might arise. 2630 [Of course, this last step is much harder than it sounds.] 2631 2632 2633Testing of U-Boot Modifications, Ports to New Hardware, etc.: 2634============================================================== 2635 2636If you have modified U-Boot sources (for instance added a new board 2637or support for new devices, a new CPU, etc.) you are expected to 2638provide feedback to the other developers. The feedback normally takes 2639the form of a "patch", i. e. a context diff against a certain (latest 2640official or latest in the git repository) version of U-Boot sources. 2641 2642But before you submit such a patch, please verify that your modifi- 2643cation did not break existing code. At least make sure that *ALL* of 2644the supported boards compile WITHOUT ANY compiler warnings. To do so, 2645just run the "MAKEALL" script, which will configure and build U-Boot 2646for ALL supported system. Be warned, this will take a while. You can 2647select which (cross) compiler to use by passing a `CROSS_COMPILE' 2648environment variable to the script, i. e. to use the ELDK cross tools 2649you can type 2650 2651 CROSS_COMPILE=ppc_8xx- MAKEALL 2652 2653or to build on a native PowerPC system you can type 2654 2655 CROSS_COMPILE=' ' MAKEALL 2656 2657When using the MAKEALL script, the default behaviour is to build 2658U-Boot in the source directory. This location can be changed by 2659setting the BUILD_DIR environment variable. Also, for each target 2660built, the MAKEALL script saves two log files (<target>.ERR and 2661<target>.MAKEALL) in the <source dir>/LOG directory. This default 2662location can be changed by setting the MAKEALL_LOGDIR environment 2663variable. For example: 2664 2665 export BUILD_DIR=/tmp/build 2666 export MAKEALL_LOGDIR=/tmp/log 2667 CROSS_COMPILE=ppc_8xx- MAKEALL 2668 2669With the above settings build objects are saved in the /tmp/build, 2670log files are saved in the /tmp/log and the source tree remains clean 2671during the whole build process. 2672 2673 2674See also "U-Boot Porting Guide" below. 2675 2676 2677Monitor Commands - Overview: 2678============================ 2679 2680go - start application at address 'addr' 2681run - run commands in an environment variable 2682bootm - boot application image from memory 2683bootp - boot image via network using BootP/TFTP protocol 2684tftpboot- boot image via network using TFTP protocol 2685 and env variables "ipaddr" and "serverip" 2686 (and eventually "gatewayip") 2687rarpboot- boot image via network using RARP/TFTP protocol 2688diskboot- boot from IDE devicebootd - boot default, i.e., run 'bootcmd' 2689loads - load S-Record file over serial line 2690loadb - load binary file over serial line (kermit mode) 2691md - memory display 2692mm - memory modify (auto-incrementing) 2693nm - memory modify (constant address) 2694mw - memory write (fill) 2695cp - memory copy 2696cmp - memory compare 2697crc32 - checksum calculation 2698imd - i2c memory display 2699imm - i2c memory modify (auto-incrementing) 2700inm - i2c memory modify (constant address) 2701imw - i2c memory write (fill) 2702icrc32 - i2c checksum calculation 2703iprobe - probe to discover valid I2C chip addresses 2704iloop - infinite loop on address range 2705isdram - print SDRAM configuration information 2706sspi - SPI utility commands 2707base - print or set address offset 2708printenv- print environment variables 2709setenv - set environment variables 2710saveenv - save environment variables to persistent storage 2711protect - enable or disable FLASH write protection 2712erase - erase FLASH memory 2713flinfo - print FLASH memory information 2714bdinfo - print Board Info structure 2715iminfo - print header information for application image 2716coninfo - print console devices and informations 2717ide - IDE sub-system 2718loop - infinite loop on address range 2719loopw - infinite write loop on address range 2720mtest - simple RAM test 2721icache - enable or disable instruction cache 2722dcache - enable or disable data cache 2723reset - Perform RESET of the CPU 2724echo - echo args to console 2725version - print monitor version 2726help - print online help 2727? - alias for 'help' 2728 2729 2730Monitor Commands - Detailed Description: 2731======================================== 2732 2733TODO. 2734 2735For now: just type "help <command>". 2736 2737 2738Environment Variables: 2739====================== 2740 2741U-Boot supports user configuration using Environment Variables which 2742can be made persistent by saving to Flash memory. 2743 2744Environment Variables are set using "setenv", printed using 2745"printenv", and saved to Flash using "saveenv". Using "setenv" 2746without a value can be used to delete a variable from the 2747environment. As long as you don't save the environment you are 2748working with an in-memory copy. In case the Flash area containing the 2749environment is erased by accident, a default environment is provided. 2750 2751Some configuration options can be set using Environment Variables: 2752 2753 baudrate - see CONFIG_BAUDRATE 2754 2755 bootdelay - see CONFIG_BOOTDELAY 2756 2757 bootcmd - see CONFIG_BOOTCOMMAND 2758 2759 bootargs - Boot arguments when booting an RTOS image 2760 2761 bootfile - Name of the image to load with TFTP 2762 2763 bootm_low - Memory range available for image processing in the bootm 2764 command can be restricted. This variable is given as 2765 a hexadecimal number and defines lowest address allowed 2766 for use by the bootm command. See also "bootm_size" 2767 environment variable. Address defined by "bootm_low" is 2768 also the base of the initial memory mapping for the Linux 2769 kernel -- see the descripton of CFG_BOOTMAPSZ. 2770 2771 bootm_size - Memory range available for image processing in the bootm 2772 command can be restricted. This variable is given as 2773 a hexadecimal number and defines the size of the region 2774 allowed for use by the bootm command. See also "bootm_low" 2775 environment variable. 2776 2777 autoload - if set to "no" (any string beginning with 'n'), 2778 "bootp" will just load perform a lookup of the 2779 configuration from the BOOTP server, but not try to 2780 load any image using TFTP 2781 2782 autoscript - if set to "yes" commands like "loadb", "loady", 2783 "bootp", "tftpb", "rarpboot" and "nfs" will attempt 2784 to automatically run script images (by internally 2785 calling "autoscript"). 2786 2787 autoscript_uname - if script image is in a format (FIT) this 2788 variable is used to get script subimage unit name. 2789 2790 autostart - if set to "yes", an image loaded using the "bootp", 2791 "rarpboot", "tftpboot" or "diskboot" commands will 2792 be automatically started (by internally calling 2793 "bootm") 2794 2795 If set to "no", a standalone image passed to the 2796 "bootm" command will be copied to the load address 2797 (and eventually uncompressed), but NOT be started. 2798 This can be used to load and uncompress arbitrary 2799 data. 2800 2801 i2cfast - (PPC405GP|PPC405EP only) 2802 if set to 'y' configures Linux I2C driver for fast 2803 mode (400kHZ). This environment variable is used in 2804 initialization code. So, for changes to be effective 2805 it must be saved and board must be reset. 2806 2807 initrd_high - restrict positioning of initrd images: 2808 If this variable is not set, initrd images will be 2809 copied to the highest possible address in RAM; this 2810 is usually what you want since it allows for 2811 maximum initrd size. If for some reason you want to 2812 make sure that the initrd image is loaded below the 2813 CFG_BOOTMAPSZ limit, you can set this environment 2814 variable to a value of "no" or "off" or "0". 2815 Alternatively, you can set it to a maximum upper 2816 address to use (U-Boot will still check that it 2817 does not overwrite the U-Boot stack and data). 2818 2819 For instance, when you have a system with 16 MB 2820 RAM, and want to reserve 4 MB from use by Linux, 2821 you can do this by adding "mem=12M" to the value of 2822 the "bootargs" variable. However, now you must make 2823 sure that the initrd image is placed in the first 2824 12 MB as well - this can be done with 2825 2826 setenv initrd_high 00c00000 2827 2828 If you set initrd_high to 0xFFFFFFFF, this is an 2829 indication to U-Boot that all addresses are legal 2830 for the Linux kernel, including addresses in flash 2831 memory. In this case U-Boot will NOT COPY the 2832 ramdisk at all. This may be useful to reduce the 2833 boot time on your system, but requires that this 2834 feature is supported by your Linux kernel. 2835 2836 ipaddr - IP address; needed for tftpboot command 2837 2838 loadaddr - Default load address for commands like "bootp", 2839 "rarpboot", "tftpboot", "loadb" or "diskboot" 2840 2841 loads_echo - see CONFIG_LOADS_ECHO 2842 2843 serverip - TFTP server IP address; needed for tftpboot command 2844 2845 bootretry - see CONFIG_BOOT_RETRY_TIME 2846 2847 bootdelaykey - see CONFIG_AUTOBOOT_DELAY_STR 2848 2849 bootstopkey - see CONFIG_AUTOBOOT_STOP_STR 2850 2851 ethprime - When CONFIG_NET_MULTI is enabled controls which 2852 interface is used first. 2853 2854 ethact - When CONFIG_NET_MULTI is enabled controls which 2855 interface is currently active. For example you 2856 can do the following 2857 2858 => setenv ethact FEC ETHERNET 2859 => ping 192.168.0.1 # traffic sent on FEC ETHERNET 2860 => setenv ethact SCC ETHERNET 2861 => ping 10.0.0.1 # traffic sent on SCC ETHERNET 2862 2863 ethrotate - When set to "no" U-Boot does not go through all 2864 available network interfaces. 2865 It just stays at the currently selected interface. 2866 2867 netretry - When set to "no" each network operation will 2868 either succeed or fail without retrying. 2869 When set to "once" the network operation will 2870 fail when all the available network interfaces 2871 are tried once without success. 2872 Useful on scripts which control the retry operation 2873 themselves. 2874 2875 npe_ucode - see CONFIG_IXP4XX_NPE_EXT_UCOD 2876 if set load address for the npe microcode 2877 2878 tftpsrcport - If this is set, the value is used for TFTP's 2879 UDP source port. 2880 2881 tftpdstport - If this is set, the value is used for TFTP's UDP 2882 destination port instead of the Well Know Port 69. 2883 2884 vlan - When set to a value < 4095 the traffic over 2885 ethernet is encapsulated/received over 802.1q 2886 VLAN tagged frames. 2887 2888The following environment variables may be used and automatically 2889updated by the network boot commands ("bootp" and "rarpboot"), 2890depending the information provided by your boot server: 2891 2892 bootfile - see above 2893 dnsip - IP address of your Domain Name Server 2894 dnsip2 - IP address of your secondary Domain Name Server 2895 gatewayip - IP address of the Gateway (Router) to use 2896 hostname - Target hostname 2897 ipaddr - see above 2898 netmask - Subnet Mask 2899 rootpath - Pathname of the root filesystem on the NFS server 2900 serverip - see above 2901 2902 2903There are two special Environment Variables: 2904 2905 serial# - contains hardware identification information such 2906 as type string and/or serial number 2907 ethaddr - Ethernet address 2908 2909These variables can be set only once (usually during manufacturing of 2910the board). U-Boot refuses to delete or overwrite these variables 2911once they have been set once. 2912 2913 2914Further special Environment Variables: 2915 2916 ver - Contains the U-Boot version string as printed 2917 with the "version" command. This variable is 2918 readonly (see CONFIG_VERSION_VARIABLE). 2919 2920 2921Please note that changes to some configuration parameters may take 2922only effect after the next boot (yes, that's just like Windoze :-). 2923 2924 2925Command Line Parsing: 2926===================== 2927 2928There are two different command line parsers available with U-Boot: 2929the old "simple" one, and the much more powerful "hush" shell: 2930 2931Old, simple command line parser: 2932-------------------------------- 2933 2934- supports environment variables (through setenv / saveenv commands) 2935- several commands on one line, separated by ';' 2936- variable substitution using "... ${name} ..." syntax 2937- special characters ('$', ';') can be escaped by prefixing with '\', 2938 for example: 2939 setenv bootcmd bootm \${address} 2940- You can also escape text by enclosing in single apostrophes, for example: 2941 setenv addip 'setenv bootargs $bootargs ip=$ipaddr:$serverip:$gatewayip:$netmask:$hostname::off' 2942 2943Hush shell: 2944----------- 2945 2946- similar to Bourne shell, with control structures like 2947 if...then...else...fi, for...do...done; while...do...done, 2948 until...do...done, ... 2949- supports environment ("global") variables (through setenv / saveenv 2950 commands) and local shell variables (through standard shell syntax 2951 "name=value"); only environment variables can be used with "run" 2952 command 2953 2954General rules: 2955-------------- 2956 2957(1) If a command line (or an environment variable executed by a "run" 2958 command) contains several commands separated by semicolon, and 2959 one of these commands fails, then the remaining commands will be 2960 executed anyway. 2961 2962(2) If you execute several variables with one call to run (i. e. 2963 calling run with a list af variables as arguments), any failing 2964 command will cause "run" to terminate, i. e. the remaining 2965 variables are not executed. 2966 2967Note for Redundant Ethernet Interfaces: 2968======================================= 2969 2970Some boards come with redundant ethernet interfaces; U-Boot supports 2971such configurations and is capable of automatic selection of a 2972"working" interface when needed. MAC assignment works as follows: 2973 2974Network interfaces are numbered eth0, eth1, eth2, ... Corresponding 2975MAC addresses can be stored in the environment as "ethaddr" (=>eth0), 2976"eth1addr" (=>eth1), "eth2addr", ... 2977 2978If the network interface stores some valid MAC address (for instance 2979in SROM), this is used as default address if there is NO correspon- 2980ding setting in the environment; if the corresponding environment 2981variable is set, this overrides the settings in the card; that means: 2982 2983o If the SROM has a valid MAC address, and there is no address in the 2984 environment, the SROM's address is used. 2985 2986o If there is no valid address in the SROM, and a definition in the 2987 environment exists, then the value from the environment variable is 2988 used. 2989 2990o If both the SROM and the environment contain a MAC address, and 2991 both addresses are the same, this MAC address is used. 2992 2993o If both the SROM and the environment contain a MAC address, and the 2994 addresses differ, the value from the environment is used and a 2995 warning is printed. 2996 2997o If neither SROM nor the environment contain a MAC address, an error 2998 is raised. 2999 3000 3001Image Formats: 3002============== 3003 3004U-Boot is capable of booting (and performing other auxiliary operations on) 3005images in two formats: 3006 3007New uImage format (FIT) 3008----------------------- 3009 3010Flexible and powerful format based on Flattened Image Tree -- FIT (similar 3011to Flattened Device Tree). It allows the use of images with multiple 3012components (several kernels, ramdisks, etc.), with contents protected by 3013SHA1, MD5 or CRC32. More details are found in the doc/uImage.FIT directory. 3014 3015 3016Old uImage format 3017----------------- 3018 3019Old image format is based on binary files which can be basically anything, 3020preceded by a special header; see the definitions in include/image.h for 3021details; basically, the header defines the following image properties: 3022 3023* Target Operating System (Provisions for OpenBSD, NetBSD, FreeBSD, 3024 4.4BSD, Linux, SVR4, Esix, Solaris, Irix, SCO, Dell, NCR, VxWorks, 3025 LynxOS, pSOS, QNX, RTEMS, ARTOS; 3026 Currently supported: Linux, NetBSD, VxWorks, QNX, RTEMS, ARTOS, LynxOS). 3027* Target CPU Architecture (Provisions for Alpha, ARM, AVR32, Intel x86, 3028 IA64, MIPS, NIOS, PowerPC, IBM S390, SuperH, Sparc, Sparc 64 Bit; 3029 Currently supported: ARM, AVR32, Intel x86, MIPS, NIOS, PowerPC). 3030* Compression Type (uncompressed, gzip, bzip2) 3031* Load Address 3032* Entry Point 3033* Image Name 3034* Image Timestamp 3035 3036The header is marked by a special Magic Number, and both the header 3037and the data portions of the image are secured against corruption by 3038CRC32 checksums. 3039 3040 3041Linux Support: 3042============== 3043 3044Although U-Boot should support any OS or standalone application 3045easily, the main focus has always been on Linux during the design of 3046U-Boot. 3047 3048U-Boot includes many features that so far have been part of some 3049special "boot loader" code within the Linux kernel. Also, any 3050"initrd" images to be used are no longer part of one big Linux image; 3051instead, kernel and "initrd" are separate images. This implementation 3052serves several purposes: 3053 3054- the same features can be used for other OS or standalone 3055 applications (for instance: using compressed images to reduce the 3056 Flash memory footprint) 3057 3058- it becomes much easier to port new Linux kernel versions because 3059 lots of low-level, hardware dependent stuff are done by U-Boot 3060 3061- the same Linux kernel image can now be used with different "initrd" 3062 images; of course this also means that different kernel images can 3063 be run with the same "initrd". This makes testing easier (you don't 3064 have to build a new "zImage.initrd" Linux image when you just 3065 change a file in your "initrd"). Also, a field-upgrade of the 3066 software is easier now. 3067 3068 3069Linux HOWTO: 3070============ 3071 3072Porting Linux to U-Boot based systems: 3073--------------------------------------- 3074 3075U-Boot cannot save you from doing all the necessary modifications to 3076configure the Linux device drivers for use with your target hardware 3077(no, we don't intend to provide a full virtual machine interface to 3078Linux :-). 3079 3080But now you can ignore ALL boot loader code (in arch/ppc/mbxboot). 3081 3082Just make sure your machine specific header file (for instance 3083include/asm-ppc/tqm8xx.h) includes the same definition of the Board 3084Information structure as we define in include/u-boot.h, and make 3085sure that your definition of IMAP_ADDR uses the same value as your 3086U-Boot configuration in CFG_IMMR. 3087 3088 3089Configuring the Linux kernel: 3090----------------------------- 3091 3092No specific requirements for U-Boot. Make sure you have some root 3093device (initial ramdisk, NFS) for your target system. 3094 3095 3096Building a Linux Image: 3097----------------------- 3098 3099With U-Boot, "normal" build targets like "zImage" or "bzImage" are 3100not used. If you use recent kernel source, a new build target 3101"uImage" will exist which automatically builds an image usable by 3102U-Boot. Most older kernels also have support for a "pImage" target, 3103which was introduced for our predecessor project PPCBoot and uses a 3104100% compatible format. 3105 3106Example: 3107 3108 make TQM850L_config 3109 make oldconfig 3110 make dep 3111 make uImage 3112 3113The "uImage" build target uses a special tool (in 'tools/mkimage') to 3114encapsulate a compressed Linux kernel image with header information, 3115CRC32 checksum etc. for use with U-Boot. This is what we are doing: 3116 3117* build a standard "vmlinux" kernel image (in ELF binary format): 3118 3119* convert the kernel into a raw binary image: 3120 3121 ${CROSS_COMPILE}-objcopy -O binary \ 3122 -R .note -R .comment \ 3123 -S vmlinux linux.bin 3124 3125* compress the binary image: 3126 3127 gzip -9 linux.bin 3128 3129* package compressed binary image for U-Boot: 3130 3131 mkimage -A ppc -O linux -T kernel -C gzip \ 3132 -a 0 -e 0 -n "Linux Kernel Image" \ 3133 -d linux.bin.gz uImage 3134 3135 3136The "mkimage" tool can also be used to create ramdisk images for use 3137with U-Boot, either separated from the Linux kernel image, or 3138combined into one file. "mkimage" encapsulates the images with a 64 3139byte header containing information about target architecture, 3140operating system, image type, compression method, entry points, time 3141stamp, CRC32 checksums, etc. 3142 3143"mkimage" can be called in two ways: to verify existing images and 3144print the header information, or to build new images. 3145 3146In the first form (with "-l" option) mkimage lists the information 3147contained in the header of an existing U-Boot image; this includes 3148checksum verification: 3149 3150 tools/mkimage -l image 3151 -l ==> list image header information 3152 3153The second form (with "-d" option) is used to build a U-Boot image 3154from a "data file" which is used as image payload: 3155 3156 tools/mkimage -A arch -O os -T type -C comp -a addr -e ep \ 3157 -n name -d data_file image 3158 -A ==> set architecture to 'arch' 3159 -O ==> set operating system to 'os' 3160 -T ==> set image type to 'type' 3161 -C ==> set compression type 'comp' 3162 -a ==> set load address to 'addr' (hex) 3163 -e ==> set entry point to 'ep' (hex) 3164 -n ==> set image name to 'name' 3165 -d ==> use image data from 'datafile' 3166 3167Right now, all Linux kernels for PowerPC systems use the same load 3168address (0x00000000), but the entry point address depends on the 3169kernel version: 3170 3171- 2.2.x kernels have the entry point at 0x0000000C, 3172- 2.3.x and later kernels have the entry point at 0x00000000. 3173 3174So a typical call to build a U-Boot image would read: 3175 3176 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \ 3177 > -A ppc -O linux -T kernel -C gzip -a 0 -e 0 \ 3178 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/ppc/coffboot/vmlinux.gz \ 3179 > examples/uImage.TQM850L 3180 Image Name: 2.4.4 kernel for TQM850L 3181 Created: Wed Jul 19 02:34:59 2000 3182 Image Type: PowerPC Linux Kernel Image (gzip compressed) 3183 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB 3184 Load Address: 0x00000000 3185 Entry Point: 0x00000000 3186 3187To verify the contents of the image (or check for corruption): 3188 3189 -> tools/mkimage -l examples/uImage.TQM850L 3190 Image Name: 2.4.4 kernel for TQM850L 3191 Created: Wed Jul 19 02:34:59 2000 3192 Image Type: PowerPC Linux Kernel Image (gzip compressed) 3193 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB 3194 Load Address: 0x00000000 3195 Entry Point: 0x00000000 3196 3197NOTE: for embedded systems where boot time is critical you can trade 3198speed for memory and install an UNCOMPRESSED image instead: this 3199needs more space in Flash, but boots much faster since it does not 3200need to be uncompressed: 3201 3202 -> gunzip /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/ppc/coffboot/vmlinux.gz 3203 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \ 3204 > -A ppc -O linux -T kernel -C none -a 0 -e 0 \ 3205 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/ppc/coffboot/vmlinux \ 3206 > examples/uImage.TQM850L-uncompressed 3207 Image Name: 2.4.4 kernel for TQM850L 3208 Created: Wed Jul 19 02:34:59 2000 3209 Image Type: PowerPC Linux Kernel Image (uncompressed) 3210 Data Size: 792160 Bytes = 773.59 kB = 0.76 MB 3211 Load Address: 0x00000000 3212 Entry Point: 0x00000000 3213 3214 3215Similar you can build U-Boot images from a 'ramdisk.image.gz' file 3216when your kernel is intended to use an initial ramdisk: 3217 3218 -> tools/mkimage -n 'Simple Ramdisk Image' \ 3219 > -A ppc -O linux -T ramdisk -C gzip \ 3220 > -d /LinuxPPC/images/SIMPLE-ramdisk.image.gz examples/simple-initrd 3221 Image Name: Simple Ramdisk Image 3222 Created: Wed Jan 12 14:01:50 2000 3223 Image Type: PowerPC Linux RAMDisk Image (gzip compressed) 3224 Data Size: 566530 Bytes = 553.25 kB = 0.54 MB 3225 Load Address: 0x00000000 3226 Entry Point: 0x00000000 3227 3228 3229Installing a Linux Image: 3230------------------------- 3231 3232To downloading a U-Boot image over the serial (console) interface, 3233you must convert the image to S-Record format: 3234 3235 objcopy -I binary -O srec examples/image examples/image.srec 3236 3237The 'objcopy' does not understand the information in the U-Boot 3238image header, so the resulting S-Record file will be relative to 3239address 0x00000000. To load it to a given address, you need to 3240specify the target address as 'offset' parameter with the 'loads' 3241command. 3242 3243Example: install the image to address 0x40100000 (which on the 3244TQM8xxL is in the first Flash bank): 3245 3246 => erase 40100000 401FFFFF 3247 3248 .......... done 3249 Erased 8 sectors 3250 3251 => loads 40100000 3252 ## Ready for S-Record download ... 3253 ~>examples/image.srec 3254 1 2 3 4 5 6 7 8 9 10 11 12 13 ... 3255 ... 3256 15989 15990 15991 15992 3257 [file transfer complete] 3258 [connected] 3259 ## Start Addr = 0x00000000 3260 3261 3262You can check the success of the download using the 'iminfo' command; 3263this includes a checksum verification so you can be sure no data 3264corruption happened: 3265 3266 => imi 40100000 3267 3268 ## Checking Image at 40100000 ... 3269 Image Name: 2.2.13 for initrd on TQM850L 3270 Image Type: PowerPC Linux Kernel Image (gzip compressed) 3271 Data Size: 335725 Bytes = 327 kB = 0 MB 3272 Load Address: 00000000 3273 Entry Point: 0000000c 3274 Verifying Checksum ... OK 3275 3276 3277Boot Linux: 3278----------- 3279 3280The "bootm" command is used to boot an application that is stored in 3281memory (RAM or Flash). In case of a Linux kernel image, the contents 3282of the "bootargs" environment variable is passed to the kernel as 3283parameters. You can check and modify this variable using the 3284"printenv" and "setenv" commands: 3285 3286 3287 => printenv bootargs 3288 bootargs=root=/dev/ram 3289 3290 => setenv bootargs root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2 3291 3292 => printenv bootargs 3293 bootargs=root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2 3294 3295 => bootm 40020000 3296 ## Booting Linux kernel at 40020000 ... 3297 Image Name: 2.2.13 for NFS on TQM850L 3298 Image Type: PowerPC Linux Kernel Image (gzip compressed) 3299 Data Size: 381681 Bytes = 372 kB = 0 MB 3300 Load Address: 00000000 3301 Entry Point: 0000000c 3302 Verifying Checksum ... OK 3303 Uncompressing Kernel Image ... OK 3304 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 3305 Boot arguments: root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2 3306 time_init: decrementer frequency = 187500000/60 3307 Calibrating delay loop... 49.77 BogoMIPS 3308 Memory: 15208k available (700k kernel code, 444k data, 32k init) [c0000000,c1000000] 3309 ... 3310 3311If you want to boot a Linux kernel with initial ram disk, you pass 3312the memory addresses of both the kernel and the initrd image (PPBCOOT 3313format!) to the "bootm" command: 3314 3315 => imi 40100000 40200000 3316 3317 ## Checking Image at 40100000 ... 3318 Image Name: 2.2.13 for initrd on TQM850L 3319 Image Type: PowerPC Linux Kernel Image (gzip compressed) 3320 Data Size: 335725 Bytes = 327 kB = 0 MB 3321 Load Address: 00000000 3322 Entry Point: 0000000c 3323 Verifying Checksum ... OK 3324 3325 ## Checking Image at 40200000 ... 3326 Image Name: Simple Ramdisk Image 3327 Image Type: PowerPC Linux RAMDisk Image (gzip compressed) 3328 Data Size: 566530 Bytes = 553 kB = 0 MB 3329 Load Address: 00000000 3330 Entry Point: 00000000 3331 Verifying Checksum ... OK 3332 3333 => bootm 40100000 40200000 3334 ## Booting Linux kernel at 40100000 ... 3335 Image Name: 2.2.13 for initrd on TQM850L 3336 Image Type: PowerPC Linux Kernel Image (gzip compressed) 3337 Data Size: 335725 Bytes = 327 kB = 0 MB 3338 Load Address: 00000000 3339 Entry Point: 0000000c 3340 Verifying Checksum ... OK 3341 Uncompressing Kernel Image ... OK 3342 ## Loading RAMDisk Image at 40200000 ... 3343 Image Name: Simple Ramdisk Image 3344 Image Type: PowerPC Linux RAMDisk Image (gzip compressed) 3345 Data Size: 566530 Bytes = 553 kB = 0 MB 3346 Load Address: 00000000 3347 Entry Point: 00000000 3348 Verifying Checksum ... OK 3349 Loading Ramdisk ... OK 3350 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 3351 Boot arguments: root=/dev/ram 3352 time_init: decrementer frequency = 187500000/60 3353 Calibrating delay loop... 49.77 BogoMIPS 3354 ... 3355 RAMDISK: Compressed image found at block 0 3356 VFS: Mounted root (ext2 filesystem). 3357 3358 bash# 3359 3360Boot Linux and pass a flat device tree: 3361----------- 3362 3363First, U-Boot must be compiled with the appropriate defines. See the section 3364titled "Linux Kernel Interface" above for a more in depth explanation. The 3365following is an example of how to start a kernel and pass an updated 3366flat device tree: 3367 3368=> print oftaddr 3369oftaddr=0x300000 3370=> print oft 3371oft=oftrees/mpc8540ads.dtb 3372=> tftp $oftaddr $oft 3373Speed: 1000, full duplex 3374Using TSEC0 device 3375TFTP from server 192.168.1.1; our IP address is 192.168.1.101 3376Filename 'oftrees/mpc8540ads.dtb'. 3377Load address: 0x300000 3378Loading: # 3379done 3380Bytes transferred = 4106 (100a hex) 3381=> tftp $loadaddr $bootfile 3382Speed: 1000, full duplex 3383Using TSEC0 device 3384TFTP from server 192.168.1.1; our IP address is 192.168.1.2 3385Filename 'uImage'. 3386Load address: 0x200000 3387Loading:############ 3388done 3389Bytes transferred = 1029407 (fb51f hex) 3390=> print loadaddr 3391loadaddr=200000 3392=> print oftaddr 3393oftaddr=0x300000 3394=> bootm $loadaddr - $oftaddr 3395## Booting image at 00200000 ... 3396 Image Name: Linux-2.6.17-dirty 3397 Image Type: PowerPC Linux Kernel Image (gzip compressed) 3398 Data Size: 1029343 Bytes = 1005.2 kB 3399 Load Address: 00000000 3400 Entry Point: 00000000 3401 Verifying Checksum ... OK 3402 Uncompressing Kernel Image ... OK 3403Booting using flat device tree at 0x300000 3404Using MPC85xx ADS machine description 3405Memory CAM mapping: CAM0=256Mb, CAM1=256Mb, CAM2=0Mb residual: 0Mb 3406[snip] 3407 3408 3409More About U-Boot Image Types: 3410------------------------------ 3411 3412U-Boot supports the following image types: 3413 3414 "Standalone Programs" are directly runnable in the environment 3415 provided by U-Boot; it is expected that (if they behave 3416 well) you can continue to work in U-Boot after return from 3417 the Standalone Program. 3418 "OS Kernel Images" are usually images of some Embedded OS which 3419 will take over control completely. Usually these programs 3420 will install their own set of exception handlers, device 3421 drivers, set up the MMU, etc. - this means, that you cannot 3422 expect to re-enter U-Boot except by resetting the CPU. 3423 "RAMDisk Images" are more or less just data blocks, and their 3424 parameters (address, size) are passed to an OS kernel that is 3425 being started. 3426 "Multi-File Images" contain several images, typically an OS 3427 (Linux) kernel image and one or more data images like 3428 RAMDisks. This construct is useful for instance when you want 3429 to boot over the network using BOOTP etc., where the boot 3430 server provides just a single image file, but you want to get 3431 for instance an OS kernel and a RAMDisk image. 3432 3433 "Multi-File Images" start with a list of image sizes, each 3434 image size (in bytes) specified by an "uint32_t" in network 3435 byte order. This list is terminated by an "(uint32_t)0". 3436 Immediately after the terminating 0 follow the images, one by 3437 one, all aligned on "uint32_t" boundaries (size rounded up to 3438 a multiple of 4 bytes). 3439 3440 "Firmware Images" are binary images containing firmware (like 3441 U-Boot or FPGA images) which usually will be programmed to 3442 flash memory. 3443 3444 "Script files" are command sequences that will be executed by 3445 U-Boot's command interpreter; this feature is especially 3446 useful when you configure U-Boot to use a real shell (hush) 3447 as command interpreter. 3448 3449 3450Standalone HOWTO: 3451================= 3452 3453One of the features of U-Boot is that you can dynamically load and 3454run "standalone" applications, which can use some resources of 3455U-Boot like console I/O functions or interrupt services. 3456 3457Two simple examples are included with the sources: 3458 3459"Hello World" Demo: 3460------------------- 3461 3462'examples/hello_world.c' contains a small "Hello World" Demo 3463application; it is automatically compiled when you build U-Boot. 3464It's configured to run at address 0x00040004, so you can play with it 3465like that: 3466 3467 => loads 3468 ## Ready for S-Record download ... 3469 ~>examples/hello_world.srec 3470 1 2 3 4 5 6 7 8 9 10 11 ... 3471 [file transfer complete] 3472 [connected] 3473 ## Start Addr = 0x00040004 3474 3475 => go 40004 Hello World! This is a test. 3476 ## Starting application at 0x00040004 ... 3477 Hello World 3478 argc = 7 3479 argv[0] = "40004" 3480 argv[1] = "Hello" 3481 argv[2] = "World!" 3482 argv[3] = "This" 3483 argv[4] = "is" 3484 argv[5] = "a" 3485 argv[6] = "test." 3486 argv[7] = "<NULL>" 3487 Hit any key to exit ... 3488 3489 ## Application terminated, rc = 0x0 3490 3491Another example, which demonstrates how to register a CPM interrupt 3492handler with the U-Boot code, can be found in 'examples/timer.c'. 3493Here, a CPM timer is set up to generate an interrupt every second. 3494The interrupt service routine is trivial, just printing a '.' 3495character, but this is just a demo program. The application can be 3496controlled by the following keys: 3497 3498 ? - print current values og the CPM Timer registers 3499 b - enable interrupts and start timer 3500 e - stop timer and disable interrupts 3501 q - quit application 3502 3503 => loads 3504 ## Ready for S-Record download ... 3505 ~>examples/timer.srec 3506 1 2 3 4 5 6 7 8 9 10 11 ... 3507 [file transfer complete] 3508 [connected] 3509 ## Start Addr = 0x00040004 3510 3511 => go 40004 3512 ## Starting application at 0x00040004 ... 3513 TIMERS=0xfff00980 3514 Using timer 1 3515 tgcr @ 0xfff00980, tmr @ 0xfff00990, trr @ 0xfff00994, tcr @ 0xfff00998, tcn @ 0xfff0099c, ter @ 0xfff009b0 3516 3517Hit 'b': 3518 [q, b, e, ?] Set interval 1000000 us 3519 Enabling timer 3520Hit '?': 3521 [q, b, e, ?] ........ 3522 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0xef6, ter=0x0 3523Hit '?': 3524 [q, b, e, ?] . 3525 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x2ad4, ter=0x0 3526Hit '?': 3527 [q, b, e, ?] . 3528 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x1efc, ter=0x0 3529Hit '?': 3530 [q, b, e, ?] . 3531 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x169d, ter=0x0 3532Hit 'e': 3533 [q, b, e, ?] ...Stopping timer 3534Hit 'q': 3535 [q, b, e, ?] ## Application terminated, rc = 0x0 3536 3537 3538Minicom warning: 3539================ 3540 3541Over time, many people have reported problems when trying to use the 3542"minicom" terminal emulation program for serial download. I (wd) 3543consider minicom to be broken, and recommend not to use it. Under 3544Unix, I recommend to use C-Kermit for general purpose use (and 3545especially for kermit binary protocol download ("loadb" command), and 3546use "cu" for S-Record download ("loads" command). 3547 3548Nevertheless, if you absolutely want to use it try adding this 3549configuration to your "File transfer protocols" section: 3550 3551 Name Program Name U/D FullScr IO-Red. Multi 3552 X kermit /usr/bin/kermit -i -l %l -s Y U Y N N 3553 Y kermit /usr/bin/kermit -i -l %l -r N D Y N N 3554 3555 3556NetBSD Notes: 3557============= 3558 3559Starting at version 0.9.2, U-Boot supports NetBSD both as host 3560(build U-Boot) and target system (boots NetBSD/mpc8xx). 3561 3562Building requires a cross environment; it is known to work on 3563NetBSD/i386 with the cross-powerpc-netbsd-1.3 package (you will also 3564need gmake since the Makefiles are not compatible with BSD make). 3565Note that the cross-powerpc package does not install include files; 3566attempting to build U-Boot will fail because <machine/ansi.h> is 3567missing. This file has to be installed and patched manually: 3568 3569 # cd /usr/pkg/cross/powerpc-netbsd/include 3570 # mkdir powerpc 3571 # ln -s powerpc machine 3572 # cp /usr/src/sys/arch/powerpc/include/ansi.h powerpc/ansi.h 3573 # ${EDIT} powerpc/ansi.h ## must remove __va_list, _BSD_VA_LIST 3574 3575Native builds *don't* work due to incompatibilities between native 3576and U-Boot include files. 3577 3578Booting assumes that (the first part of) the image booted is a 3579stage-2 loader which in turn loads and then invokes the kernel 3580proper. Loader sources will eventually appear in the NetBSD source 3581tree (probably in sys/arc/mpc8xx/stand/u-boot_stage2/); in the 3582meantime, see ftp://ftp.denx.de/pub/u-boot/ppcboot_stage2.tar.gz 3583 3584 3585Implementation Internals: 3586========================= 3587 3588The following is not intended to be a complete description of every 3589implementation detail. However, it should help to understand the 3590inner workings of U-Boot and make it easier to port it to custom 3591hardware. 3592 3593 3594Initial Stack, Global Data: 3595--------------------------- 3596 3597The implementation of U-Boot is complicated by the fact that U-Boot 3598starts running out of ROM (flash memory), usually without access to 3599system RAM (because the memory controller is not initialized yet). 3600This means that we don't have writable Data or BSS segments, and BSS 3601is not initialized as zero. To be able to get a C environment working 3602at all, we have to allocate at least a minimal stack. Implementation 3603options for this are defined and restricted by the CPU used: Some CPU 3604models provide on-chip memory (like the IMMR area on MPC8xx and 3605MPC826x processors), on others (parts of) the data cache can be 3606locked as (mis-) used as memory, etc. 3607 3608 Chris Hallinan posted a good summary of these issues to the 3609 u-boot-users mailing list: 3610 3611 Subject: RE: [U-Boot-Users] RE: More On Memory Bank x (nothingness)? 3612 From: "Chris Hallinan" <clh@net1plus.com> 3613 Date: Mon, 10 Feb 2003 16:43:46 -0500 (22:43 MET) 3614 ... 3615 3616 Correct me if I'm wrong, folks, but the way I understand it 3617 is this: Using DCACHE as initial RAM for Stack, etc, does not 3618 require any physical RAM backing up the cache. The cleverness 3619 is that the cache is being used as a temporary supply of 3620 necessary storage before the SDRAM controller is setup. It's 3621 beyond the scope of this list to expain the details, but you 3622 can see how this works by studying the cache architecture and 3623 operation in the architecture and processor-specific manuals. 3624 3625 OCM is On Chip Memory, which I believe the 405GP has 4K. It 3626 is another option for the system designer to use as an 3627 initial stack/ram area prior to SDRAM being available. Either 3628 option should work for you. Using CS 4 should be fine if your 3629 board designers haven't used it for something that would 3630 cause you grief during the initial boot! It is frequently not 3631 used. 3632 3633 CFG_INIT_RAM_ADDR should be somewhere that won't interfere 3634 with your processor/board/system design. The default value 3635 you will find in any recent u-boot distribution in 3636 walnut.h should work for you. I'd set it to a value larger 3637 than your SDRAM module. If you have a 64MB SDRAM module, set 3638 it above 400_0000. Just make sure your board has no resources 3639 that are supposed to respond to that address! That code in 3640 start.S has been around a while and should work as is when 3641 you get the config right. 3642 3643 -Chris Hallinan 3644 DS4.COM, Inc. 3645 3646It is essential to remember this, since it has some impact on the C 3647code for the initialization procedures: 3648 3649* Initialized global data (data segment) is read-only. Do not attempt 3650 to write it. 3651 3652* Do not use any unitialized global data (or implicitely initialized 3653 as zero data - BSS segment) at all - this is undefined, initiali- 3654 zation is performed later (when relocating to RAM). 3655 3656* Stack space is very limited. Avoid big data buffers or things like 3657 that. 3658 3659Having only the stack as writable memory limits means we cannot use 3660normal global data to share information beween the code. But it 3661turned out that the implementation of U-Boot can be greatly 3662simplified by making a global data structure (gd_t) available to all 3663functions. We could pass a pointer to this data as argument to _all_ 3664functions, but this would bloat the code. Instead we use a feature of 3665the GCC compiler (Global Register Variables) to share the data: we 3666place a pointer (gd) to the global data into a register which we 3667reserve for this purpose. 3668 3669When choosing a register for such a purpose we are restricted by the 3670relevant (E)ABI specifications for the current architecture, and by 3671GCC's implementation. 3672 3673For PowerPC, the following registers have specific use: 3674 R1: stack pointer 3675 R2: reserved for system use 3676 R3-R4: parameter passing and return values 3677 R5-R10: parameter passing 3678 R13: small data area pointer 3679 R30: GOT pointer 3680 R31: frame pointer 3681 3682 (U-Boot also uses R14 as internal GOT pointer.) 3683 3684 ==> U-Boot will use R2 to hold a pointer to the global data 3685 3686 Note: on PPC, we could use a static initializer (since the 3687 address of the global data structure is known at compile time), 3688 but it turned out that reserving a register results in somewhat 3689 smaller code - although the code savings are not that big (on 3690 average for all boards 752 bytes for the whole U-Boot image, 3691 624 text + 127 data). 3692 3693On Blackfin, the normal C ABI (except for P5) is followed as documented here: 3694 http://docs.blackfin.uclinux.org/doku.php?id=application_binary_interface 3695 3696 ==> U-Boot will use P5 to hold a pointer to the global data 3697 3698On ARM, the following registers are used: 3699 3700 R0: function argument word/integer result 3701 R1-R3: function argument word 3702 R9: GOT pointer 3703 R10: stack limit (used only if stack checking if enabled) 3704 R11: argument (frame) pointer 3705 R12: temporary workspace 3706 R13: stack pointer 3707 R14: link register 3708 R15: program counter 3709 3710 ==> U-Boot will use R8 to hold a pointer to the global data 3711 3712NOTE: DECLARE_GLOBAL_DATA_PTR must be used with file-global scope, 3713or current versions of GCC may "optimize" the code too much. 3714 3715Memory Management: 3716------------------ 3717 3718U-Boot runs in system state and uses physical addresses, i.e. the 3719MMU is not used either for address mapping nor for memory protection. 3720 3721The available memory is mapped to fixed addresses using the memory 3722controller. In this process, a contiguous block is formed for each 3723memory type (Flash, SDRAM, SRAM), even when it consists of several 3724physical memory banks. 3725 3726U-Boot is installed in the first 128 kB of the first Flash bank (on 3727TQM8xxL modules this is the range 0x40000000 ... 0x4001FFFF). After 3728booting and sizing and initializing DRAM, the code relocates itself 3729to the upper end of DRAM. Immediately below the U-Boot code some 3730memory is reserved for use by malloc() [see CFG_MALLOC_LEN 3731configuration setting]. Below that, a structure with global Board 3732Info data is placed, followed by the stack (growing downward). 3733 3734Additionally, some exception handler code is copied to the low 8 kB 3735of DRAM (0x00000000 ... 0x00001FFF). 3736 3737So a typical memory configuration with 16 MB of DRAM could look like 3738this: 3739 3740 0x0000 0000 Exception Vector code 3741 : 3742 0x0000 1FFF 3743 0x0000 2000 Free for Application Use 3744 : 3745 : 3746 3747 : 3748 : 3749 0x00FB FF20 Monitor Stack (Growing downward) 3750 0x00FB FFAC Board Info Data and permanent copy of global data 3751 0x00FC 0000 Malloc Arena 3752 : 3753 0x00FD FFFF 3754 0x00FE 0000 RAM Copy of Monitor Code 3755 ... eventually: LCD or video framebuffer 3756 ... eventually: pRAM (Protected RAM - unchanged by reset) 3757 0x00FF FFFF [End of RAM] 3758 3759 3760System Initialization: 3761---------------------- 3762 3763In the reset configuration, U-Boot starts at the reset entry point 3764(on most PowerPC systens at address 0x00000100). Because of the reset 3765configuration for CS0# this is a mirror of the onboard Flash memory. 3766To be able to re-map memory U-Boot then jumps to its link address. 3767To be able to implement the initialization code in C, a (small!) 3768initial stack is set up in the internal Dual Ported RAM (in case CPUs 3769which provide such a feature like MPC8xx or MPC8260), or in a locked 3770part of the data cache. After that, U-Boot initializes the CPU core, 3771the caches and the SIU. 3772 3773Next, all (potentially) available memory banks are mapped using a 3774preliminary mapping. For example, we put them on 512 MB boundaries 3775(multiples of 0x20000000: SDRAM on 0x00000000 and 0x20000000, Flash 3776on 0x40000000 and 0x60000000, SRAM on 0x80000000). Then UPM A is 3777programmed for SDRAM access. Using the temporary configuration, a 3778simple memory test is run that determines the size of the SDRAM 3779banks. 3780 3781When there is more than one SDRAM bank, and the banks are of 3782different size, the largest is mapped first. For equal size, the first 3783bank (CS2#) is mapped first. The first mapping is always for address 37840x00000000, with any additional banks following immediately to create 3785contiguous memory starting from 0. 3786 3787Then, the monitor installs itself at the upper end of the SDRAM area 3788and allocates memory for use by malloc() and for the global Board 3789Info data; also, the exception vector code is copied to the low RAM 3790pages, and the final stack is set up. 3791 3792Only after this relocation will you have a "normal" C environment; 3793until that you are restricted in several ways, mostly because you are 3794running from ROM, and because the code will have to be relocated to a 3795new address in RAM. 3796 3797 3798U-Boot Porting Guide: 3799---------------------- 3800 3801[Based on messages by Jerry Van Baren in the U-Boot-Users mailing 3802list, October 2002] 3803 3804 3805int main (int argc, char *argv[]) 3806{ 3807 sighandler_t no_more_time; 3808 3809 signal (SIGALRM, no_more_time); 3810 alarm (PROJECT_DEADLINE - toSec (3 * WEEK)); 3811 3812 if (available_money > available_manpower) { 3813 pay consultant to port U-Boot; 3814 return 0; 3815 } 3816 3817 Download latest U-Boot source; 3818 3819 Subscribe to u-boot-users mailing list; 3820 3821 if (clueless) { 3822 email ("Hi, I am new to U-Boot, how do I get started?"); 3823 } 3824 3825 while (learning) { 3826 Read the README file in the top level directory; 3827 Read http://www.denx.de/twiki/bin/view/DULG/Manual ; 3828 Read the source, Luke; 3829 } 3830 3831 if (available_money > toLocalCurrency ($2500)) { 3832 Buy a BDI2000; 3833 } else { 3834 Add a lot of aggravation and time; 3835 } 3836 3837 Create your own board support subdirectory; 3838 3839 Create your own board config file; 3840 3841 while (!running) { 3842 do { 3843 Add / modify source code; 3844 } until (compiles); 3845 Debug; 3846 if (clueless) 3847 email ("Hi, I am having problems..."); 3848 } 3849 Send patch file to Wolfgang; 3850 3851 return 0; 3852} 3853 3854void no_more_time (int sig) 3855{ 3856 hire_a_guru(); 3857} 3858 3859 3860Coding Standards: 3861----------------- 3862 3863All contributions to U-Boot should conform to the Linux kernel 3864coding style; see the file "Documentation/CodingStyle" and the script 3865"scripts/Lindent" in your Linux kernel source directory. In sources 3866originating from U-Boot a style corresponding to "Lindent -pcs" (adding 3867spaces before parameters to function calls) is actually used. 3868 3869Source files originating from a different project (for example the 3870MTD subsystem) are generally exempt from these guidelines and are not 3871reformated to ease subsequent migration to newer versions of those 3872sources. 3873 3874Please note that U-Boot is implemented in C (and to some small parts in 3875Assembler); no C++ is used, so please do not use C++ style comments (//) 3876in your code. 3877 3878Please also stick to the following formatting rules: 3879- remove any trailing white space 3880- use TAB characters for indentation, not spaces 3881- make sure NOT to use DOS '\r\n' line feeds 3882- do not add more than 2 empty lines to source files 3883- do not add trailing empty lines to source files 3884 3885Submissions which do not conform to the standards may be returned 3886with a request to reformat the changes. 3887 3888 3889Submitting Patches: 3890------------------- 3891 3892Since the number of patches for U-Boot is growing, we need to 3893establish some rules. Submissions which do not conform to these rules 3894may be rejected, even when they contain important and valuable stuff. 3895 3896Patches shall be sent to the u-boot-users mailing list. 3897 3898Please see http://www.denx.de/wiki/UBoot/Patches for details. 3899 3900When you send a patch, please include the following information with 3901it: 3902 3903* For bug fixes: a description of the bug and how your patch fixes 3904 this bug. Please try to include a way of demonstrating that the 3905 patch actually fixes something. 3906 3907* For new features: a description of the feature and your 3908 implementation. 3909 3910* A CHANGELOG entry as plaintext (separate from the patch) 3911 3912* For major contributions, your entry to the CREDITS file 3913 3914* When you add support for a new board, don't forget to add this 3915 board to the MAKEALL script, too. 3916 3917* If your patch adds new configuration options, don't forget to 3918 document these in the README file. 3919 3920* The patch itself. If you are using git (which is *strongly* 3921 recommended) you can easily generate the patch using the 3922 "git-format-patch". If you then use "git-send-email" to send it to 3923 the U-Boot mailing list, you will avoid most of the common problems 3924 with some other mail clients. 3925 3926 If you cannot use git, use "diff -purN OLD NEW". If your version of 3927 diff does not support these options, then get the latest version of 3928 GNU diff. 3929 3930 The current directory when running this command shall be the parent 3931 directory of the U-Boot source tree (i. e. please make sure that 3932 your patch includes sufficient directory information for the 3933 affected files). 3934 3935 We prefer patches as plain text. MIME attachments are discouraged, 3936 and compressed attachments must not be used. 3937 3938* If one logical set of modifications affects or creates several 3939 files, all these changes shall be submitted in a SINGLE patch file. 3940 3941* Changesets that contain different, unrelated modifications shall be 3942 submitted as SEPARATE patches, one patch per changeset. 3943 3944 3945Notes: 3946 3947* Before sending the patch, run the MAKEALL script on your patched 3948 source tree and make sure that no errors or warnings are reported 3949 for any of the boards. 3950 3951* Keep your modifications to the necessary minimum: A patch 3952 containing several unrelated changes or arbitrary reformats will be 3953 returned with a request to re-formatting / split it. 3954 3955* If you modify existing code, make sure that your new code does not 3956 add to the memory footprint of the code ;-) Small is beautiful! 3957 When adding new features, these should compile conditionally only 3958 (using #ifdef), and the resulting code with the new feature 3959 disabled must not need more memory than the old code without your 3960 modification. 3961 3962* Remember that there is a size limit of 40 kB per message on the 3963 u-boot-users mailing list. Bigger patches will be moderated. If 3964 they are reasonable and not bigger than 100 kB, they will be 3965 acknowledged. Even bigger patches should be avoided. 3966