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_MC146818 - use MC146818 RTC 676 CONFIG_RTC_DS1307 - use Maxim, Inc. DS1307 RTC 677 CONFIG_RTC_DS1337 - use Maxim, Inc. DS1337 RTC 678 CONFIG_RTC_DS1338 - use Maxim, Inc. DS1338 RTC 679 CONFIG_RTC_DS164x - use Dallas DS164x RTC 680 CONFIG_RTC_ISL1208 - use Intersil ISL1208 RTC 681 CONFIG_RTC_MAX6900 - use Maxim, Inc. MAX6900 RTC 682 CFG_RTC_DS1337_NOOSC - Turn off the OSC output for DS1337 683 684 Note that if the RTC uses I2C, then the I2C interface 685 must also be configured. See I2C Support, below. 686 687- Timestamp Support: 688 689 When CONFIG_TIMESTAMP is selected, the timestamp 690 (date and time) of an image is printed by image 691 commands like bootm or iminfo. This option is 692 automatically enabled when you select CONFIG_CMD_DATE . 693 694- Partition Support: 695 CONFIG_MAC_PARTITION and/or CONFIG_DOS_PARTITION 696 and/or CONFIG_ISO_PARTITION 697 698 If IDE or SCSI support is enabled (CONFIG_CMD_IDE or 699 CONFIG_CMD_SCSI) you must configure support for at 700 least one partition type as well. 701 702- IDE Reset method: 703 CONFIG_IDE_RESET_ROUTINE - this is defined in several 704 board configurations files but used nowhere! 705 706 CONFIG_IDE_RESET - is this is defined, IDE Reset will 707 be performed by calling the function 708 ide_set_reset(int reset) 709 which has to be defined in a board specific file 710 711- ATAPI Support: 712 CONFIG_ATAPI 713 714 Set this to enable ATAPI support. 715 716- LBA48 Support 717 CONFIG_LBA48 718 719 Set this to enable support for disks larger than 137GB 720 Also look at CFG_64BIT_LBA ,CFG_64BIT_VSPRINTF and CFG_64BIT_STRTOUL 721 Whithout these , LBA48 support uses 32bit variables and will 'only' 722 support disks up to 2.1TB. 723 724 CFG_64BIT_LBA: 725 When enabled, makes the IDE subsystem use 64bit sector addresses. 726 Default is 32bit. 727 728- SCSI Support: 729 At the moment only there is only support for the 730 SYM53C8XX SCSI controller; define 731 CONFIG_SCSI_SYM53C8XX to enable it. 732 733 CFG_SCSI_MAX_LUN [8], CFG_SCSI_MAX_SCSI_ID [7] and 734 CFG_SCSI_MAX_DEVICE [CFG_SCSI_MAX_SCSI_ID * 735 CFG_SCSI_MAX_LUN] can be adjusted to define the 736 maximum numbers of LUNs, SCSI ID's and target 737 devices. 738 CFG_SCSI_SYM53C8XX_CCF to fix clock timing (80Mhz) 739 740- NETWORK Support (PCI): 741 CONFIG_E1000 742 Support for Intel 8254x gigabit chips. 743 744 CONFIG_E1000_FALLBACK_MAC 745 default MAC for empty eeprom after production. 746 747 CONFIG_EEPRO100 748 Support for Intel 82557/82559/82559ER chips. 749 Optional CONFIG_EEPRO100_SROM_WRITE enables eeprom 750 write routine for first time initialisation. 751 752 CONFIG_TULIP 753 Support for Digital 2114x chips. 754 Optional CONFIG_TULIP_SELECT_MEDIA for board specific 755 modem chip initialisation (KS8761/QS6611). 756 757 CONFIG_NATSEMI 758 Support for National dp83815 chips. 759 760 CONFIG_NS8382X 761 Support for National dp8382[01] gigabit chips. 762 763- NETWORK Support (other): 764 765 CONFIG_DRIVER_LAN91C96 766 Support for SMSC's LAN91C96 chips. 767 768 CONFIG_LAN91C96_BASE 769 Define this to hold the physical address 770 of the LAN91C96's I/O space 771 772 CONFIG_LAN91C96_USE_32_BIT 773 Define this to enable 32 bit addressing 774 775 CONFIG_DRIVER_SMC91111 776 Support for SMSC's LAN91C111 chip 777 778 CONFIG_SMC91111_BASE 779 Define this to hold the physical address 780 of the device (I/O space) 781 782 CONFIG_SMC_USE_32_BIT 783 Define this if data bus is 32 bits 784 785 CONFIG_SMC_USE_IOFUNCS 786 Define this to use i/o functions instead of macros 787 (some hardware wont work with macros) 788 789- USB Support: 790 At the moment only the UHCI host controller is 791 supported (PIP405, MIP405, MPC5200); define 792 CONFIG_USB_UHCI to enable it. 793 define CONFIG_USB_KEYBOARD to enable the USB Keyboard 794 and define CONFIG_USB_STORAGE to enable the USB 795 storage devices. 796 Note: 797 Supported are USB Keyboards and USB Floppy drives 798 (TEAC FD-05PUB). 799 MPC5200 USB requires additional defines: 800 CONFIG_USB_CLOCK 801 for 528 MHz Clock: 0x0001bbbb 802 CONFIG_USB_CONFIG 803 for differential drivers: 0x00001000 804 for single ended drivers: 0x00005000 805 CFG_USB_EVENT_POLL 806 May be defined to allow interrupt polling 807 instead of using asynchronous interrupts 808 809- USB Device: 810 Define the below if you wish to use the USB console. 811 Once firmware is rebuilt from a serial console issue the 812 command "setenv stdin usbtty; setenv stdout usbtty" and 813 attach your usb cable. The Unix command "dmesg" should print 814 it has found a new device. The environment variable usbtty 815 can be set to gserial or cdc_acm to enable your device to 816 appear to a USB host as a Linux gserial device or a 817 Common Device Class Abstract Control Model serial device. 818 If you select usbtty = gserial you should be able to enumerate 819 a Linux host by 820 # modprobe usbserial vendor=0xVendorID product=0xProductID 821 else if using cdc_acm, simply setting the environment 822 variable usbtty to be cdc_acm should suffice. The following 823 might be defined in YourBoardName.h 824 825 CONFIG_USB_DEVICE 826 Define this to build a UDC device 827 828 CONFIG_USB_TTY 829 Define this to have a tty type of device available to 830 talk to the UDC device 831 832 CFG_CONSOLE_IS_IN_ENV 833 Define this if you want stdin, stdout &/or stderr to 834 be set to usbtty. 835 836 mpc8xx: 837 CFG_USB_EXTC_CLK 0xBLAH 838 Derive USB clock from external clock "blah" 839 - CFG_USB_EXTC_CLK 0x02 840 841 CFG_USB_BRG_CLK 0xBLAH 842 Derive USB clock from brgclk 843 - CFG_USB_BRG_CLK 0x04 844 845 If you have a USB-IF assigned VendorID then you may wish to 846 define your own vendor specific values either in BoardName.h 847 or directly in usbd_vendor_info.h. If you don't define 848 CONFIG_USBD_MANUFACTURER, CONFIG_USBD_PRODUCT_NAME, 849 CONFIG_USBD_VENDORID and CONFIG_USBD_PRODUCTID, then U-Boot 850 should pretend to be a Linux device to it's target host. 851 852 CONFIG_USBD_MANUFACTURER 853 Define this string as the name of your company for 854 - CONFIG_USBD_MANUFACTURER "my company" 855 856 CONFIG_USBD_PRODUCT_NAME 857 Define this string as the name of your product 858 - CONFIG_USBD_PRODUCT_NAME "acme usb device" 859 860 CONFIG_USBD_VENDORID 861 Define this as your assigned Vendor ID from the USB 862 Implementors Forum. This *must* be a genuine Vendor ID 863 to avoid polluting the USB namespace. 864 - CONFIG_USBD_VENDORID 0xFFFF 865 866 CONFIG_USBD_PRODUCTID 867 Define this as the unique Product ID 868 for your device 869 - CONFIG_USBD_PRODUCTID 0xFFFF 870 871 872- MMC Support: 873 The MMC controller on the Intel PXA is supported. To 874 enable this define CONFIG_MMC. The MMC can be 875 accessed from the boot prompt by mapping the device 876 to physical memory similar to flash. Command line is 877 enabled with CONFIG_CMD_MMC. The MMC driver also works with 878 the FAT fs. This is enabled with CONFIG_CMD_FAT. 879 880- Journaling Flash filesystem support: 881 CONFIG_JFFS2_NAND, CONFIG_JFFS2_NAND_OFF, CONFIG_JFFS2_NAND_SIZE, 882 CONFIG_JFFS2_NAND_DEV 883 Define these for a default partition on a NAND device 884 885 CFG_JFFS2_FIRST_SECTOR, 886 CFG_JFFS2_FIRST_BANK, CFG_JFFS2_NUM_BANKS 887 Define these for a default partition on a NOR device 888 889 CFG_JFFS_CUSTOM_PART 890 Define this to create an own partition. You have to provide a 891 function struct part_info* jffs2_part_info(int part_num) 892 893 If you define only one JFFS2 partition you may also want to 894 #define CFG_JFFS_SINGLE_PART 1 895 to disable the command chpart. This is the default when you 896 have not defined a custom partition 897 898- Keyboard Support: 899 CONFIG_ISA_KEYBOARD 900 901 Define this to enable standard (PC-Style) keyboard 902 support 903 904 CONFIG_I8042_KBD 905 Standard PC keyboard driver with US (is default) and 906 GERMAN key layout (switch via environment 'keymap=de') support. 907 Export function i8042_kbd_init, i8042_tstc and i8042_getc 908 for cfb_console. Supports cursor blinking. 909 910- Video support: 911 CONFIG_VIDEO 912 913 Define this to enable video support (for output to 914 video). 915 916 CONFIG_VIDEO_CT69000 917 918 Enable Chips & Technologies 69000 Video chip 919 920 CONFIG_VIDEO_SMI_LYNXEM 921 Enable Silicon Motion SMI 712/710/810 Video chip. The 922 video output is selected via environment 'videoout' 923 (1 = LCD and 2 = CRT). If videoout is undefined, CRT is 924 assumed. 925 926 For the CT69000 and SMI_LYNXEM drivers, videomode is 927 selected via environment 'videomode'. Two diferent ways 928 are possible: 929 - "videomode=num" 'num' is a standard LiLo mode numbers. 930 Following standard modes are supported (* is default): 931 932 Colors 640x480 800x600 1024x768 1152x864 1280x1024 933 -------------+--------------------------------------------- 934 8 bits | 0x301* 0x303 0x305 0x161 0x307 935 15 bits | 0x310 0x313 0x316 0x162 0x319 936 16 bits | 0x311 0x314 0x317 0x163 0x31A 937 24 bits | 0x312 0x315 0x318 ? 0x31B 938 -------------+--------------------------------------------- 939 (i.e. setenv videomode 317; saveenv; reset;) 940 941 - "videomode=bootargs" all the video parameters are parsed 942 from the bootargs. (See drivers/video/videomodes.c) 943 944 945 CONFIG_VIDEO_SED13806 946 Enable Epson SED13806 driver. This driver supports 8bpp 947 and 16bpp modes defined by CONFIG_VIDEO_SED13806_8BPP 948 or CONFIG_VIDEO_SED13806_16BPP 949 950- Keyboard Support: 951 CONFIG_KEYBOARD 952 953 Define this to enable a custom keyboard support. 954 This simply calls drv_keyboard_init() which must be 955 defined in your board-specific files. 956 The only board using this so far is RBC823. 957 958- LCD Support: CONFIG_LCD 959 960 Define this to enable LCD support (for output to LCD 961 display); also select one of the supported displays 962 by defining one of these: 963 964 CONFIG_NEC_NL6448AC33: 965 966 NEC NL6448AC33-18. Active, color, single scan. 967 968 CONFIG_NEC_NL6448BC20 969 970 NEC NL6448BC20-08. 6.5", 640x480. 971 Active, color, single scan. 972 973 CONFIG_NEC_NL6448BC33_54 974 975 NEC NL6448BC33-54. 10.4", 640x480. 976 Active, color, single scan. 977 978 CONFIG_SHARP_16x9 979 980 Sharp 320x240. Active, color, single scan. 981 It isn't 16x9, and I am not sure what it is. 982 983 CONFIG_SHARP_LQ64D341 984 985 Sharp LQ64D341 display, 640x480. 986 Active, color, single scan. 987 988 CONFIG_HLD1045 989 990 HLD1045 display, 640x480. 991 Active, color, single scan. 992 993 CONFIG_OPTREX_BW 994 995 Optrex CBL50840-2 NF-FW 99 22 M5 996 or 997 Hitachi LMG6912RPFC-00T 998 or 999 Hitachi SP14Q002 1000 1001 320x240. Black & white. 1002 1003 Normally display is black on white background; define 1004 CFG_WHITE_ON_BLACK to get it inverted. 1005 1006- Splash Screen Support: CONFIG_SPLASH_SCREEN 1007 1008 If this option is set, the environment is checked for 1009 a variable "splashimage". If found, the usual display 1010 of logo, copyright and system information on the LCD 1011 is suppressed and the BMP image at the address 1012 specified in "splashimage" is loaded instead. The 1013 console is redirected to the "nulldev", too. This 1014 allows for a "silent" boot where a splash screen is 1015 loaded very quickly after power-on. 1016 1017- Gzip compressed BMP image support: CONFIG_VIDEO_BMP_GZIP 1018 1019 If this option is set, additionally to standard BMP 1020 images, gzipped BMP images can be displayed via the 1021 splashscreen support or the bmp command. 1022 1023- Compression support: 1024 CONFIG_BZIP2 1025 1026 If this option is set, support for bzip2 compressed 1027 images is included. If not, only uncompressed and gzip 1028 compressed images are supported. 1029 1030 NOTE: the bzip2 algorithm requires a lot of RAM, so 1031 the malloc area (as defined by CFG_MALLOC_LEN) should 1032 be at least 4MB. 1033 1034- MII/PHY support: 1035 CONFIG_PHY_ADDR 1036 1037 The address of PHY on MII bus. 1038 1039 CONFIG_PHY_CLOCK_FREQ (ppc4xx) 1040 1041 The clock frequency of the MII bus 1042 1043 CONFIG_PHY_GIGE 1044 1045 If this option is set, support for speed/duplex 1046 detection of Gigabit PHY is included. 1047 1048 CONFIG_PHY_RESET_DELAY 1049 1050 Some PHY like Intel LXT971A need extra delay after 1051 reset before any MII register access is possible. 1052 For such PHY, set this option to the usec delay 1053 required. (minimum 300usec for LXT971A) 1054 1055 CONFIG_PHY_CMD_DELAY (ppc4xx) 1056 1057 Some PHY like Intel LXT971A need extra delay after 1058 command issued before MII status register can be read 1059 1060- Ethernet address: 1061 CONFIG_ETHADDR 1062 CONFIG_ETH2ADDR 1063 CONFIG_ETH3ADDR 1064 1065 Define a default value for ethernet address to use 1066 for the respective ethernet interface, in case this 1067 is not determined automatically. 1068 1069- IP address: 1070 CONFIG_IPADDR 1071 1072 Define a default value for the IP address to use for 1073 the default ethernet interface, in case this is not 1074 determined through e.g. bootp. 1075 1076- Server IP address: 1077 CONFIG_SERVERIP 1078 1079 Defines a default value for theIP address of a TFTP 1080 server to contact when using the "tftboot" command. 1081 1082- Multicast TFTP Mode: 1083 CONFIG_MCAST_TFTP 1084 1085 Defines whether you want to support multicast TFTP as per 1086 rfc-2090; for example to work with atftp. Lets lots of targets 1087 tftp down the same boot image concurrently. Note: the ethernet 1088 driver in use must provide a function: mcast() to join/leave a 1089 multicast group. 1090 1091 CONFIG_BOOTP_RANDOM_DELAY 1092- BOOTP Recovery Mode: 1093 CONFIG_BOOTP_RANDOM_DELAY 1094 1095 If you have many targets in a network that try to 1096 boot using BOOTP, you may want to avoid that all 1097 systems send out BOOTP requests at precisely the same 1098 moment (which would happen for instance at recovery 1099 from a power failure, when all systems will try to 1100 boot, thus flooding the BOOTP server. Defining 1101 CONFIG_BOOTP_RANDOM_DELAY causes a random delay to be 1102 inserted before sending out BOOTP requests. The 1103 following delays are inserted then: 1104 1105 1st BOOTP request: delay 0 ... 1 sec 1106 2nd BOOTP request: delay 0 ... 2 sec 1107 3rd BOOTP request: delay 0 ... 4 sec 1108 4th and following 1109 BOOTP requests: delay 0 ... 8 sec 1110 1111- DHCP Advanced Options: 1112 You can fine tune the DHCP functionality by defining 1113 CONFIG_BOOTP_* symbols: 1114 1115 CONFIG_BOOTP_SUBNETMASK 1116 CONFIG_BOOTP_GATEWAY 1117 CONFIG_BOOTP_HOSTNAME 1118 CONFIG_BOOTP_NISDOMAIN 1119 CONFIG_BOOTP_BOOTPATH 1120 CONFIG_BOOTP_BOOTFILESIZE 1121 CONFIG_BOOTP_DNS 1122 CONFIG_BOOTP_DNS2 1123 CONFIG_BOOTP_SEND_HOSTNAME 1124 CONFIG_BOOTP_NTPSERVER 1125 CONFIG_BOOTP_TIMEOFFSET 1126 CONFIG_BOOTP_VENDOREX 1127 1128 CONFIG_BOOTP_SERVERIP - TFTP server will be the serverip 1129 environment variable, not the BOOTP server. 1130 1131 CONFIG_BOOTP_DNS2 - If a DHCP client requests the DNS 1132 serverip from a DHCP server, it is possible that more 1133 than one DNS serverip is offered to the client. 1134 If CONFIG_BOOTP_DNS2 is enabled, the secondary DNS 1135 serverip will be stored in the additional environment 1136 variable "dnsip2". The first DNS serverip is always 1137 stored in the variable "dnsip", when CONFIG_BOOTP_DNS 1138 is defined. 1139 1140 CONFIG_BOOTP_SEND_HOSTNAME - Some DHCP servers are capable 1141 to do a dynamic update of a DNS server. To do this, they 1142 need the hostname of the DHCP requester. 1143 If CONFIG_BOOTP_SEND_HOSTNAME is defined, the content 1144 of the "hostname" environment variable is passed as 1145 option 12 to the DHCP server. 1146 1147 CONFIG_BOOTP_DHCP_REQUEST_DELAY 1148 1149 A 32bit value in microseconds for a delay between 1150 receiving a "DHCP Offer" and sending the "DHCP Request". 1151 This fixes a problem with certain DHCP servers that don't 1152 respond 100% of the time to a "DHCP request". E.g. On an 1153 AT91RM9200 processor running at 180MHz, this delay needed 1154 to be *at least* 15,000 usec before a Windows Server 2003 1155 DHCP server would reply 100% of the time. I recommend at 1156 least 50,000 usec to be safe. The alternative is to hope 1157 that one of the retries will be successful but note that 1158 the DHCP timeout and retry process takes a longer than 1159 this delay. 1160 1161 - CDP Options: 1162 CONFIG_CDP_DEVICE_ID 1163 1164 The device id used in CDP trigger frames. 1165 1166 CONFIG_CDP_DEVICE_ID_PREFIX 1167 1168 A two character string which is prefixed to the MAC address 1169 of the device. 1170 1171 CONFIG_CDP_PORT_ID 1172 1173 A printf format string which contains the ascii name of 1174 the port. Normally is set to "eth%d" which sets 1175 eth0 for the first ethernet, eth1 for the second etc. 1176 1177 CONFIG_CDP_CAPABILITIES 1178 1179 A 32bit integer which indicates the device capabilities; 1180 0x00000010 for a normal host which does not forwards. 1181 1182 CONFIG_CDP_VERSION 1183 1184 An ascii string containing the version of the software. 1185 1186 CONFIG_CDP_PLATFORM 1187 1188 An ascii string containing the name of the platform. 1189 1190 CONFIG_CDP_TRIGGER 1191 1192 A 32bit integer sent on the trigger. 1193 1194 CONFIG_CDP_POWER_CONSUMPTION 1195 1196 A 16bit integer containing the power consumption of the 1197 device in .1 of milliwatts. 1198 1199 CONFIG_CDP_APPLIANCE_VLAN_TYPE 1200 1201 A byte containing the id of the VLAN. 1202 1203- Status LED: CONFIG_STATUS_LED 1204 1205 Several configurations allow to display the current 1206 status using a LED. For instance, the LED will blink 1207 fast while running U-Boot code, stop blinking as 1208 soon as a reply to a BOOTP request was received, and 1209 start blinking slow once the Linux kernel is running 1210 (supported by a status LED driver in the Linux 1211 kernel). Defining CONFIG_STATUS_LED enables this 1212 feature in U-Boot. 1213 1214- CAN Support: CONFIG_CAN_DRIVER 1215 1216 Defining CONFIG_CAN_DRIVER enables CAN driver support 1217 on those systems that support this (optional) 1218 feature, like the TQM8xxL modules. 1219 1220- I2C Support: CONFIG_HARD_I2C | CONFIG_SOFT_I2C 1221 1222 These enable I2C serial bus commands. Defining either of 1223 (but not both of) CONFIG_HARD_I2C or CONFIG_SOFT_I2C will 1224 include the appropriate I2C driver for the selected cpu. 1225 1226 This will allow you to use i2c commands at the u-boot 1227 command line (as long as you set CONFIG_CMD_I2C in 1228 CONFIG_COMMANDS) and communicate with i2c based realtime 1229 clock chips. See common/cmd_i2c.c for a description of the 1230 command line interface. 1231 1232 CONFIG_I2C_CMD_TREE is a recommended option that places 1233 all I2C commands under a single 'i2c' root command. The 1234 older 'imm', 'imd', 'iprobe' etc. commands are considered 1235 deprecated and may disappear in the future. 1236 1237 CONFIG_HARD_I2C selects a hardware I2C controller. 1238 1239 CONFIG_SOFT_I2C configures u-boot to use a software (aka 1240 bit-banging) driver instead of CPM or similar hardware 1241 support for I2C. 1242 1243 There are several other quantities that must also be 1244 defined when you define CONFIG_HARD_I2C or CONFIG_SOFT_I2C. 1245 1246 In both cases you will need to define CFG_I2C_SPEED 1247 to be the frequency (in Hz) at which you wish your i2c bus 1248 to run and CFG_I2C_SLAVE to be the address of this node (ie 1249 the cpu's i2c node address). 1250 1251 Now, the u-boot i2c code for the mpc8xx (cpu/mpc8xx/i2c.c) 1252 sets the cpu up as a master node and so its address should 1253 therefore be cleared to 0 (See, eg, MPC823e User's Manual 1254 p.16-473). So, set CFG_I2C_SLAVE to 0. 1255 1256 That's all that's required for CONFIG_HARD_I2C. 1257 1258 If you use the software i2c interface (CONFIG_SOFT_I2C) 1259 then the following macros need to be defined (examples are 1260 from include/configs/lwmon.h): 1261 1262 I2C_INIT 1263 1264 (Optional). Any commands necessary to enable the I2C 1265 controller or configure ports. 1266 1267 eg: #define I2C_INIT (immr->im_cpm.cp_pbdir |= PB_SCL) 1268 1269 I2C_PORT 1270 1271 (Only for MPC8260 CPU). The I/O port to use (the code 1272 assumes both bits are on the same port). Valid values 1273 are 0..3 for ports A..D. 1274 1275 I2C_ACTIVE 1276 1277 The code necessary to make the I2C data line active 1278 (driven). If the data line is open collector, this 1279 define can be null. 1280 1281 eg: #define I2C_ACTIVE (immr->im_cpm.cp_pbdir |= PB_SDA) 1282 1283 I2C_TRISTATE 1284 1285 The code necessary to make the I2C data line tri-stated 1286 (inactive). If the data line is open collector, this 1287 define can be null. 1288 1289 eg: #define I2C_TRISTATE (immr->im_cpm.cp_pbdir &= ~PB_SDA) 1290 1291 I2C_READ 1292 1293 Code that returns TRUE if the I2C data line is high, 1294 FALSE if it is low. 1295 1296 eg: #define I2C_READ ((immr->im_cpm.cp_pbdat & PB_SDA) != 0) 1297 1298 I2C_SDA(bit) 1299 1300 If <bit> is TRUE, sets the I2C data line high. If it 1301 is FALSE, it clears it (low). 1302 1303 eg: #define I2C_SDA(bit) \ 1304 if(bit) immr->im_cpm.cp_pbdat |= PB_SDA; \ 1305 else immr->im_cpm.cp_pbdat &= ~PB_SDA 1306 1307 I2C_SCL(bit) 1308 1309 If <bit> is TRUE, sets the I2C clock line high. If it 1310 is FALSE, it clears it (low). 1311 1312 eg: #define I2C_SCL(bit) \ 1313 if(bit) immr->im_cpm.cp_pbdat |= PB_SCL; \ 1314 else immr->im_cpm.cp_pbdat &= ~PB_SCL 1315 1316 I2C_DELAY 1317 1318 This delay is invoked four times per clock cycle so this 1319 controls the rate of data transfer. The data rate thus 1320 is 1 / (I2C_DELAY * 4). Often defined to be something 1321 like: 1322 1323 #define I2C_DELAY udelay(2) 1324 1325 CFG_I2C_INIT_BOARD 1326 1327 When a board is reset during an i2c bus transfer 1328 chips might think that the current transfer is still 1329 in progress. On some boards it is possible to access 1330 the i2c SCLK line directly, either by using the 1331 processor pin as a GPIO or by having a second pin 1332 connected to the bus. If this option is defined a 1333 custom i2c_init_board() routine in boards/xxx/board.c 1334 is run early in the boot sequence. 1335 1336 CONFIG_I2CFAST (PPC405GP|PPC405EP only) 1337 1338 This option enables configuration of bi_iic_fast[] flags 1339 in u-boot bd_info structure based on u-boot environment 1340 variable "i2cfast". (see also i2cfast) 1341 1342 CONFIG_I2C_MULTI_BUS 1343 1344 This option allows the use of multiple I2C buses, each of which 1345 must have a controller. At any point in time, only one bus is 1346 active. To switch to a different bus, use the 'i2c dev' command. 1347 Note that bus numbering is zero-based. 1348 1349 CFG_I2C_NOPROBES 1350 1351 This option specifies a list of I2C devices that will be skipped 1352 when the 'i2c probe' command is issued (or 'iprobe' using the legacy 1353 command). If CONFIG_I2C_MULTI_BUS is set, specify a list of bus-device 1354 pairs. Otherwise, specify a 1D array of device addresses 1355 1356 e.g. 1357 #undef CONFIG_I2C_MULTI_BUS 1358 #define CFG_I2C_NOPROBES {0x50,0x68} 1359 1360 will skip addresses 0x50 and 0x68 on a board with one I2C bus 1361 1362 #define CONFIG_I2C_MULTI_BUS 1363 #define CFG_I2C_MULTI_NOPROBES {{0,0x50},{0,0x68},{1,0x54}} 1364 1365 will skip addresses 0x50 and 0x68 on bus 0 and address 0x54 on bus 1 1366 1367 CFG_SPD_BUS_NUM 1368 1369 If defined, then this indicates the I2C bus number for DDR SPD. 1370 If not defined, then U-Boot assumes that SPD is on I2C bus 0. 1371 1372 CFG_RTC_BUS_NUM 1373 1374 If defined, then this indicates the I2C bus number for the RTC. 1375 If not defined, then U-Boot assumes that RTC is on I2C bus 0. 1376 1377 CFG_DTT_BUS_NUM 1378 1379 If defined, then this indicates the I2C bus number for the DTT. 1380 If not defined, then U-Boot assumes that DTT is on I2C bus 0. 1381 1382 CONFIG_FSL_I2C 1383 1384 Define this option if you want to use Freescale's I2C driver in 1385 drivers/i2c/fsl_i2c.c. 1386 1387 1388- SPI Support: CONFIG_SPI 1389 1390 Enables SPI driver (so far only tested with 1391 SPI EEPROM, also an instance works with Crystal A/D and 1392 D/As on the SACSng board) 1393 1394 CONFIG_SPI_X 1395 1396 Enables extended (16-bit) SPI EEPROM addressing. 1397 (symmetrical to CONFIG_I2C_X) 1398 1399 CONFIG_SOFT_SPI 1400 1401 Enables a software (bit-bang) SPI driver rather than 1402 using hardware support. This is a general purpose 1403 driver that only requires three general I/O port pins 1404 (two outputs, one input) to function. If this is 1405 defined, the board configuration must define several 1406 SPI configuration items (port pins to use, etc). For 1407 an example, see include/configs/sacsng.h. 1408 1409 CONFIG_HARD_SPI 1410 1411 Enables a hardware SPI driver for general-purpose reads 1412 and writes. As with CONFIG_SOFT_SPI, the board configuration 1413 must define a list of chip-select function pointers. 1414 Currently supported on some MPC8xxx processors. For an 1415 example, see include/configs/mpc8349emds.h. 1416 1417 CONFIG_MXC_SPI 1418 1419 Enables the driver for the SPI controllers on i.MX and MXC 1420 SoCs. Currently only i.MX31 is supported. 1421 1422- FPGA Support: CONFIG_FPGA 1423 1424 Enables FPGA subsystem. 1425 1426 CONFIG_FPGA_<vendor> 1427 1428 Enables support for specific chip vendors. 1429 (ALTERA, XILINX) 1430 1431 CONFIG_FPGA_<family> 1432 1433 Enables support for FPGA family. 1434 (SPARTAN2, SPARTAN3, VIRTEX2, CYCLONE2, ACEX1K, ACEX) 1435 1436 CONFIG_FPGA_COUNT 1437 1438 Specify the number of FPGA devices to support. 1439 1440 CFG_FPGA_PROG_FEEDBACK 1441 1442 Enable printing of hash marks during FPGA configuration. 1443 1444 CFG_FPGA_CHECK_BUSY 1445 1446 Enable checks on FPGA configuration interface busy 1447 status by the configuration function. This option 1448 will require a board or device specific function to 1449 be written. 1450 1451 CONFIG_FPGA_DELAY 1452 1453 If defined, a function that provides delays in the FPGA 1454 configuration driver. 1455 1456 CFG_FPGA_CHECK_CTRLC 1457 Allow Control-C to interrupt FPGA configuration 1458 1459 CFG_FPGA_CHECK_ERROR 1460 1461 Check for configuration errors during FPGA bitfile 1462 loading. For example, abort during Virtex II 1463 configuration if the INIT_B line goes low (which 1464 indicated a CRC error). 1465 1466 CFG_FPGA_WAIT_INIT 1467 1468 Maximum time to wait for the INIT_B line to deassert 1469 after PROB_B has been deasserted during a Virtex II 1470 FPGA configuration sequence. The default time is 500 1471 mS. 1472 1473 CFG_FPGA_WAIT_BUSY 1474 1475 Maximum time to wait for BUSY to deassert during 1476 Virtex II FPGA configuration. The default is 5 mS. 1477 1478 CFG_FPGA_WAIT_CONFIG 1479 1480 Time to wait after FPGA configuration. The default is 1481 200 mS. 1482 1483- Configuration Management: 1484 CONFIG_IDENT_STRING 1485 1486 If defined, this string will be added to the U-Boot 1487 version information (U_BOOT_VERSION) 1488 1489- Vendor Parameter Protection: 1490 1491 U-Boot considers the values of the environment 1492 variables "serial#" (Board Serial Number) and 1493 "ethaddr" (Ethernet Address) to be parameters that 1494 are set once by the board vendor / manufacturer, and 1495 protects these variables from casual modification by 1496 the user. Once set, these variables are read-only, 1497 and write or delete attempts are rejected. You can 1498 change this behviour: 1499 1500 If CONFIG_ENV_OVERWRITE is #defined in your config 1501 file, the write protection for vendor parameters is 1502 completely disabled. Anybody can change or delete 1503 these parameters. 1504 1505 Alternatively, if you #define _both_ CONFIG_ETHADDR 1506 _and_ CONFIG_OVERWRITE_ETHADDR_ONCE, a default 1507 ethernet address is installed in the environment, 1508 which can be changed exactly ONCE by the user. [The 1509 serial# is unaffected by this, i. e. it remains 1510 read-only.] 1511 1512- Protected RAM: 1513 CONFIG_PRAM 1514 1515 Define this variable to enable the reservation of 1516 "protected RAM", i. e. RAM which is not overwritten 1517 by U-Boot. Define CONFIG_PRAM to hold the number of 1518 kB you want to reserve for pRAM. You can overwrite 1519 this default value by defining an environment 1520 variable "pram" to the number of kB you want to 1521 reserve. Note that the board info structure will 1522 still show the full amount of RAM. If pRAM is 1523 reserved, a new environment variable "mem" will 1524 automatically be defined to hold the amount of 1525 remaining RAM in a form that can be passed as boot 1526 argument to Linux, for instance like that: 1527 1528 setenv bootargs ... mem=\${mem} 1529 saveenv 1530 1531 This way you can tell Linux not to use this memory, 1532 either, which results in a memory region that will 1533 not be affected by reboots. 1534 1535 *WARNING* If your board configuration uses automatic 1536 detection of the RAM size, you must make sure that 1537 this memory test is non-destructive. So far, the 1538 following board configurations are known to be 1539 "pRAM-clean": 1540 1541 ETX094, IVMS8, IVML24, SPD8xx, TQM8xxL, 1542 HERMES, IP860, RPXlite, LWMON, LANTEC, 1543 PCU_E, FLAGADM, TQM8260 1544 1545- Error Recovery: 1546 CONFIG_PANIC_HANG 1547 1548 Define this variable to stop the system in case of a 1549 fatal error, so that you have to reset it manually. 1550 This is probably NOT a good idea for an embedded 1551 system where you want to system to reboot 1552 automatically as fast as possible, but it may be 1553 useful during development since you can try to debug 1554 the conditions that lead to the situation. 1555 1556 CONFIG_NET_RETRY_COUNT 1557 1558 This variable defines the number of retries for 1559 network operations like ARP, RARP, TFTP, or BOOTP 1560 before giving up the operation. If not defined, a 1561 default value of 5 is used. 1562 1563- Command Interpreter: 1564 CONFIG_AUTO_COMPLETE 1565 1566 Enable auto completion of commands using TAB. 1567 1568 Note that this feature has NOT been implemented yet 1569 for the "hush" shell. 1570 1571 1572 CFG_HUSH_PARSER 1573 1574 Define this variable to enable the "hush" shell (from 1575 Busybox) as command line interpreter, thus enabling 1576 powerful command line syntax like 1577 if...then...else...fi conditionals or `&&' and '||' 1578 constructs ("shell scripts"). 1579 1580 If undefined, you get the old, much simpler behaviour 1581 with a somewhat smaller memory footprint. 1582 1583 1584 CFG_PROMPT_HUSH_PS2 1585 1586 This defines the secondary prompt string, which is 1587 printed when the command interpreter needs more input 1588 to complete a command. Usually "> ". 1589 1590 Note: 1591 1592 In the current implementation, the local variables 1593 space and global environment variables space are 1594 separated. Local variables are those you define by 1595 simply typing `name=value'. To access a local 1596 variable later on, you have write `$name' or 1597 `${name}'; to execute the contents of a variable 1598 directly type `$name' at the command prompt. 1599 1600 Global environment variables are those you use 1601 setenv/printenv to work with. To run a command stored 1602 in such a variable, you need to use the run command, 1603 and you must not use the '$' sign to access them. 1604 1605 To store commands and special characters in a 1606 variable, please use double quotation marks 1607 surrounding the whole text of the variable, instead 1608 of the backslashes before semicolons and special 1609 symbols. 1610 1611- Commandline Editing and History: 1612 CONFIG_CMDLINE_EDITING 1613 1614 Enable editiong and History functions for interactive 1615 commandline input operations 1616 1617- Default Environment: 1618 CONFIG_EXTRA_ENV_SETTINGS 1619 1620 Define this to contain any number of null terminated 1621 strings (variable = value pairs) that will be part of 1622 the default environment compiled into the boot image. 1623 1624 For example, place something like this in your 1625 board's config file: 1626 1627 #define CONFIG_EXTRA_ENV_SETTINGS \ 1628 "myvar1=value1\0" \ 1629 "myvar2=value2\0" 1630 1631 Warning: This method is based on knowledge about the 1632 internal format how the environment is stored by the 1633 U-Boot code. This is NOT an official, exported 1634 interface! Although it is unlikely that this format 1635 will change soon, there is no guarantee either. 1636 You better know what you are doing here. 1637 1638 Note: overly (ab)use of the default environment is 1639 discouraged. Make sure to check other ways to preset 1640 the environment like the autoscript function or the 1641 boot command first. 1642 1643- DataFlash Support: 1644 CONFIG_HAS_DATAFLASH 1645 1646 Defining this option enables DataFlash features and 1647 allows to read/write in Dataflash via the standard 1648 commands cp, md... 1649 1650- SystemACE Support: 1651 CONFIG_SYSTEMACE 1652 1653 Adding this option adds support for Xilinx SystemACE 1654 chips attached via some sort of local bus. The address 1655 of the chip must alsh be defined in the 1656 CFG_SYSTEMACE_BASE macro. For example: 1657 1658 #define CONFIG_SYSTEMACE 1659 #define CFG_SYSTEMACE_BASE 0xf0000000 1660 1661 When SystemACE support is added, the "ace" device type 1662 becomes available to the fat commands, i.e. fatls. 1663 1664- TFTP Fixed UDP Port: 1665 CONFIG_TFTP_PORT 1666 1667 If this is defined, the environment variable tftpsrcp 1668 is used to supply the TFTP UDP source port value. 1669 If tftpsrcp isn't defined, the normal pseudo-random port 1670 number generator is used. 1671 1672 Also, the environment variable tftpdstp is used to supply 1673 the TFTP UDP destination port value. If tftpdstp isn't 1674 defined, the normal port 69 is used. 1675 1676 The purpose for tftpsrcp is to allow a TFTP server to 1677 blindly start the TFTP transfer using the pre-configured 1678 target IP address and UDP port. This has the effect of 1679 "punching through" the (Windows XP) firewall, allowing 1680 the remainder of the TFTP transfer to proceed normally. 1681 A better solution is to properly configure the firewall, 1682 but sometimes that is not allowed. 1683 1684- Show boot progress: 1685 CONFIG_SHOW_BOOT_PROGRESS 1686 1687 Defining this option allows to add some board- 1688 specific code (calling a user-provided function 1689 "show_boot_progress(int)") that enables you to show 1690 the system's boot progress on some display (for 1691 example, some LED's) on your board. At the moment, 1692 the following checkpoints are implemented: 1693 1694Legacy uImage format: 1695 1696 Arg Where When 1697 1 common/cmd_bootm.c before attempting to boot an image 1698 -1 common/cmd_bootm.c Image header has bad magic number 1699 2 common/cmd_bootm.c Image header has correct magic number 1700 -2 common/cmd_bootm.c Image header has bad checksum 1701 3 common/cmd_bootm.c Image header has correct checksum 1702 -3 common/cmd_bootm.c Image data has bad checksum 1703 4 common/cmd_bootm.c Image data has correct checksum 1704 -4 common/cmd_bootm.c Image is for unsupported architecture 1705 5 common/cmd_bootm.c Architecture check OK 1706 -5 common/cmd_bootm.c Wrong Image Type (not kernel, multi) 1707 6 common/cmd_bootm.c Image Type check OK 1708 -6 common/cmd_bootm.c gunzip uncompression error 1709 -7 common/cmd_bootm.c Unimplemented compression type 1710 7 common/cmd_bootm.c Uncompression OK 1711 8 common/cmd_bootm.c No uncompress/copy overwrite error 1712 -9 common/cmd_bootm.c Unsupported OS (not Linux, BSD, VxWorks, QNX) 1713 1714 9 common/image.c Start initial ramdisk verification 1715 -10 common/image.c Ramdisk header has bad magic number 1716 -11 common/image.c Ramdisk header has bad checksum 1717 10 common/image.c Ramdisk header is OK 1718 -12 common/image.c Ramdisk data has bad checksum 1719 11 common/image.c Ramdisk data has correct checksum 1720 12 common/image.c Ramdisk verification complete, start loading 1721 -13 common/image.c Wrong Image Type (not PPC Linux Ramdisk) 1722 13 common/image.c Start multifile image verification 1723 14 common/image.c No initial ramdisk, no multifile, continue. 1724 1725 15 lib_<arch>/bootm.c All preparation done, transferring control to OS 1726 1727 -30 lib_ppc/board.c Fatal error, hang the system 1728 -31 post/post.c POST test failed, detected by post_output_backlog() 1729 -32 post/post.c POST test failed, detected by post_run_single() 1730 1731 34 common/cmd_doc.c before loading a Image from a DOC device 1732 -35 common/cmd_doc.c Bad usage of "doc" command 1733 35 common/cmd_doc.c correct usage of "doc" command 1734 -36 common/cmd_doc.c No boot device 1735 36 common/cmd_doc.c correct boot device 1736 -37 common/cmd_doc.c Unknown Chip ID on boot device 1737 37 common/cmd_doc.c correct chip ID found, device available 1738 -38 common/cmd_doc.c Read Error on boot device 1739 38 common/cmd_doc.c reading Image header from DOC device OK 1740 -39 common/cmd_doc.c Image header has bad magic number 1741 39 common/cmd_doc.c Image header has correct magic number 1742 -40 common/cmd_doc.c Error reading Image from DOC device 1743 40 common/cmd_doc.c Image header has correct magic number 1744 41 common/cmd_ide.c before loading a Image from a IDE device 1745 -42 common/cmd_ide.c Bad usage of "ide" command 1746 42 common/cmd_ide.c correct usage of "ide" command 1747 -43 common/cmd_ide.c No boot device 1748 43 common/cmd_ide.c boot device found 1749 -44 common/cmd_ide.c Device not available 1750 44 common/cmd_ide.c Device available 1751 -45 common/cmd_ide.c wrong partition selected 1752 45 common/cmd_ide.c partition selected 1753 -46 common/cmd_ide.c Unknown partition table 1754 46 common/cmd_ide.c valid partition table found 1755 -47 common/cmd_ide.c Invalid partition type 1756 47 common/cmd_ide.c correct partition type 1757 -48 common/cmd_ide.c Error reading Image Header on boot device 1758 48 common/cmd_ide.c reading Image Header from IDE device OK 1759 -49 common/cmd_ide.c Image header has bad magic number 1760 49 common/cmd_ide.c Image header has correct magic number 1761 -50 common/cmd_ide.c Image header has bad checksum 1762 50 common/cmd_ide.c Image header has correct checksum 1763 -51 common/cmd_ide.c Error reading Image from IDE device 1764 51 common/cmd_ide.c reading Image from IDE device OK 1765 52 common/cmd_nand.c before loading a Image from a NAND device 1766 -53 common/cmd_nand.c Bad usage of "nand" command 1767 53 common/cmd_nand.c correct usage of "nand" command 1768 -54 common/cmd_nand.c No boot device 1769 54 common/cmd_nand.c boot device found 1770 -55 common/cmd_nand.c Unknown Chip ID on boot device 1771 55 common/cmd_nand.c correct chip ID found, device available 1772 -56 common/cmd_nand.c Error reading Image Header on boot device 1773 56 common/cmd_nand.c reading Image Header from NAND device OK 1774 -57 common/cmd_nand.c Image header has bad magic number 1775 57 common/cmd_nand.c Image header has correct magic number 1776 -58 common/cmd_nand.c Error reading Image from NAND device 1777 58 common/cmd_nand.c reading Image from NAND device OK 1778 1779 -60 common/env_common.c Environment has a bad CRC, using default 1780 1781 64 net/eth.c starting with Ethernetconfiguration. 1782 -64 net/eth.c no Ethernet found. 1783 65 net/eth.c Ethernet found. 1784 1785 -80 common/cmd_net.c usage wrong 1786 80 common/cmd_net.c before calling NetLoop() 1787 -81 common/cmd_net.c some error in NetLoop() occured 1788 81 common/cmd_net.c NetLoop() back without error 1789 -82 common/cmd_net.c size == 0 (File with size 0 loaded) 1790 82 common/cmd_net.c trying automatic boot 1791 83 common/cmd_net.c running autoscript 1792 -83 common/cmd_net.c some error in automatic boot or autoscript 1793 84 common/cmd_net.c end without errors 1794 1795FIT uImage format: 1796 1797 Arg Where When 1798 100 common/cmd_bootm.c Kernel FIT Image has correct format 1799 -100 common/cmd_bootm.c Kernel FIT Image has incorrect format 1800 101 common/cmd_bootm.c No Kernel subimage unit name, using configuration 1801 -101 common/cmd_bootm.c Can't get configuration for kernel subimage 1802 102 common/cmd_bootm.c Kernel unit name specified 1803 -103 common/cmd_bootm.c Can't get kernel subimage node offset 1804 103 common/cmd_bootm.c Found configuration node 1805 104 common/cmd_bootm.c Got kernel subimage node offset 1806 -104 common/cmd_bootm.c Kernel subimage hash verification failed 1807 105 common/cmd_bootm.c Kernel subimage hash verification OK 1808 -105 common/cmd_bootm.c Kernel subimage is for unsupported architecture 1809 106 common/cmd_bootm.c Architecture check OK 1810 -106 common/cmd_bootm.c Kernel subimage has wrong typea 1811 107 common/cmd_bootm.c Kernel subimge type OK 1812 -107 common/cmd_bootm.c Can't get kernel subimage data/size 1813 108 common/cmd_bootm.c Got kernel subimage data/size 1814 -108 common/cmd_bootm.c Wrong image type (not legacy, FIT) 1815 -109 common/cmd_bootm.c Can't get kernel subimage type 1816 -110 common/cmd_bootm.c Can't get kernel subimage comp 1817 -111 common/cmd_bootm.c Can't get kernel subimage os 1818 -112 common/cmd_bootm.c Can't get kernel subimage load address 1819 -113 common/cmd_bootm.c Image uncompress/copy overwrite error 1820 1821 120 common/image.c Start initial ramdisk verification 1822 -120 common/image.c Ramdisk FIT image has incorrect format 1823 121 common/image.c Ramdisk FIT image has correct format 1824 122 common/image.c No Ramdisk subimage unit name, using configuration 1825 -122 common/image.c Can't get configuration for ramdisk subimage 1826 123 common/image.c Ramdisk unit name specified 1827 -124 common/image.c Can't get ramdisk subimage node offset 1828 125 common/image.c Got ramdisk subimage node offset 1829 -125 common/image.c Ramdisk subimage hash verification failed 1830 126 common/image.c Ramdisk subimage hash verification OK 1831 -126 common/image.c Ramdisk subimage for unsupported architecture 1832 127 common/image.c Architecture check OK 1833 -127 common/image.c Can't get ramdisk subimage data/size 1834 128 common/image.c Got ramdisk subimage data/size 1835 129 common/image.c Can't get ramdisk load address 1836 -129 common/image.c Got ramdisk load address 1837 1838 -130 common/cmd_doc.c Icorrect FIT image format 1839 131 common/cmd_doc.c FIT image format OK 1840 1841 -140 common/cmd_ide.c Icorrect FIT image format 1842 141 common/cmd_ide.c FIT image format OK 1843 1844 -150 common/cmd_nand.c Icorrect FIT image format 1845 151 common/cmd_nand.c FIT image format OK 1846 1847 1848Modem Support: 1849-------------- 1850 1851[so far only for SMDK2400 and TRAB boards] 1852 1853- Modem support endable: 1854 CONFIG_MODEM_SUPPORT 1855 1856- RTS/CTS Flow control enable: 1857 CONFIG_HWFLOW 1858 1859- Modem debug support: 1860 CONFIG_MODEM_SUPPORT_DEBUG 1861 1862 Enables debugging stuff (char screen[1024], dbg()) 1863 for modem support. Useful only with BDI2000. 1864 1865- Interrupt support (PPC): 1866 1867 There are common interrupt_init() and timer_interrupt() 1868 for all PPC archs. interrupt_init() calls interrupt_init_cpu() 1869 for cpu specific initialization. interrupt_init_cpu() 1870 should set decrementer_count to appropriate value. If 1871 cpu resets decrementer automatically after interrupt 1872 (ppc4xx) it should set decrementer_count to zero. 1873 timer_interrupt() calls timer_interrupt_cpu() for cpu 1874 specific handling. If board has watchdog / status_led 1875 / other_activity_monitor it works automatically from 1876 general timer_interrupt(). 1877 1878- General: 1879 1880 In the target system modem support is enabled when a 1881 specific key (key combination) is pressed during 1882 power-on. Otherwise U-Boot will boot normally 1883 (autoboot). The key_pressed() fuction is called from 1884 board_init(). Currently key_pressed() is a dummy 1885 function, returning 1 and thus enabling modem 1886 initialization. 1887 1888 If there are no modem init strings in the 1889 environment, U-Boot proceed to autoboot; the 1890 previous output (banner, info printfs) will be 1891 supressed, though. 1892 1893 See also: doc/README.Modem 1894 1895 1896Configuration Settings: 1897----------------------- 1898 1899- CFG_LONGHELP: Defined when you want long help messages included; 1900 undefine this when you're short of memory. 1901 1902- CFG_PROMPT: This is what U-Boot prints on the console to 1903 prompt for user input. 1904 1905- CFG_CBSIZE: Buffer size for input from the Console 1906 1907- CFG_PBSIZE: Buffer size for Console output 1908 1909- CFG_MAXARGS: max. Number of arguments accepted for monitor commands 1910 1911- CFG_BARGSIZE: Buffer size for Boot Arguments which are passed to 1912 the application (usually a Linux kernel) when it is 1913 booted 1914 1915- CFG_BAUDRATE_TABLE: 1916 List of legal baudrate settings for this board. 1917 1918- CFG_CONSOLE_INFO_QUIET 1919 Suppress display of console information at boot. 1920 1921- CFG_CONSOLE_IS_IN_ENV 1922 If the board specific function 1923 extern int overwrite_console (void); 1924 returns 1, the stdin, stderr and stdout are switched to the 1925 serial port, else the settings in the environment are used. 1926 1927- CFG_CONSOLE_OVERWRITE_ROUTINE 1928 Enable the call to overwrite_console(). 1929 1930- CFG_CONSOLE_ENV_OVERWRITE 1931 Enable overwrite of previous console environment settings. 1932 1933- CFG_MEMTEST_START, CFG_MEMTEST_END: 1934 Begin and End addresses of the area used by the 1935 simple memory test. 1936 1937- CFG_ALT_MEMTEST: 1938 Enable an alternate, more extensive memory test. 1939 1940- CFG_MEMTEST_SCRATCH: 1941 Scratch address used by the alternate memory test 1942 You only need to set this if address zero isn't writeable 1943 1944- CFG_MEM_TOP_HIDE (PPC only): 1945 If CFG_MEM_TOP_HIDE is defined in the board config header, 1946 this specified memory area will get subtracted from the top 1947 (end) of ram and won't get "touched" at all by U-Boot. By 1948 fixing up gd->ram_size the Linux kernel should gets passed 1949 the now "corrected" memory size and won't touch it either. 1950 This should work for arch/ppc and arch/powerpc. Only Linux 1951 board ports in arch/powerpc with bootwrapper support that 1952 recalculate the memory size from the SDRAM controller setup 1953 will have to get fixed in Linux additionally. 1954 1955 This option can be used as a workaround for the 440EPx/GRx 1956 CHIP 11 errata where the last 256 bytes in SDRAM shouldn't 1957 be touched. 1958 1959 WARNING: Please make sure that this value is a multiple of 1960 the Linux page size (normally 4k). If this is not the case, 1961 then the end address of the Linux memory will be located at a 1962 non page size aligned address and this could cause major 1963 problems. 1964 1965- CFG_TFTP_LOADADDR: 1966 Default load address for network file downloads 1967 1968- CFG_LOADS_BAUD_CHANGE: 1969 Enable temporary baudrate change while serial download 1970 1971- CFG_SDRAM_BASE: 1972 Physical start address of SDRAM. _Must_ be 0 here. 1973 1974- CFG_MBIO_BASE: 1975 Physical start address of Motherboard I/O (if using a 1976 Cogent motherboard) 1977 1978- CFG_FLASH_BASE: 1979 Physical start address of Flash memory. 1980 1981- CFG_MONITOR_BASE: 1982 Physical start address of boot monitor code (set by 1983 make config files to be same as the text base address 1984 (TEXT_BASE) used when linking) - same as 1985 CFG_FLASH_BASE when booting from flash. 1986 1987- CFG_MONITOR_LEN: 1988 Size of memory reserved for monitor code, used to 1989 determine _at_compile_time_ (!) if the environment is 1990 embedded within the U-Boot image, or in a separate 1991 flash sector. 1992 1993- CFG_MALLOC_LEN: 1994 Size of DRAM reserved for malloc() use. 1995 1996- CFG_BOOTM_LEN: 1997 Normally compressed uImages are limited to an 1998 uncompressed size of 8 MBytes. If this is not enough, 1999 you can define CFG_BOOTM_LEN in your board config file 2000 to adjust this setting to your needs. 2001 2002- CFG_BOOTMAPSZ: 2003 Maximum size of memory mapped by the startup code of 2004 the Linux kernel; all data that must be processed by 2005 the Linux kernel (bd_info, boot arguments, FDT blob if 2006 used) must be put below this limit, unless "bootm_low" 2007 enviroment variable is defined and non-zero. In such case 2008 all data for the Linux kernel must be between "bootm_low" 2009 and "bootm_low" + CFG_BOOTMAPSZ. 2010 2011- CFG_MAX_FLASH_BANKS: 2012 Max number of Flash memory banks 2013 2014- CFG_MAX_FLASH_SECT: 2015 Max number of sectors on a Flash chip 2016 2017- CFG_FLASH_ERASE_TOUT: 2018 Timeout for Flash erase operations (in ms) 2019 2020- CFG_FLASH_WRITE_TOUT: 2021 Timeout for Flash write operations (in ms) 2022 2023- CFG_FLASH_LOCK_TOUT 2024 Timeout for Flash set sector lock bit operation (in ms) 2025 2026- CFG_FLASH_UNLOCK_TOUT 2027 Timeout for Flash clear lock bits operation (in ms) 2028 2029- CFG_FLASH_PROTECTION 2030 If defined, hardware flash sectors protection is used 2031 instead of U-Boot software protection. 2032 2033- CFG_DIRECT_FLASH_TFTP: 2034 2035 Enable TFTP transfers directly to flash memory; 2036 without this option such a download has to be 2037 performed in two steps: (1) download to RAM, and (2) 2038 copy from RAM to flash. 2039 2040 The two-step approach is usually more reliable, since 2041 you can check if the download worked before you erase 2042 the flash, but in some situations (when sytem RAM is 2043 too limited to allow for a tempory copy of the 2044 downloaded image) this option may be very useful. 2045 2046- CFG_FLASH_CFI: 2047 Define if the flash driver uses extra elements in the 2048 common flash structure for storing flash geometry. 2049 2050- CFG_FLASH_CFI_DRIVER 2051 This option also enables the building of the cfi_flash driver 2052 in the drivers directory 2053 2054- CFG_FLASH_USE_BUFFER_WRITE 2055 Use buffered writes to flash. 2056 2057- CONFIG_FLASH_SPANSION_S29WS_N 2058 s29ws-n MirrorBit flash has non-standard addresses for buffered 2059 write commands. 2060 2061- CFG_FLASH_QUIET_TEST 2062 If this option is defined, the common CFI flash doesn't 2063 print it's warning upon not recognized FLASH banks. This 2064 is useful, if some of the configured banks are only 2065 optionally available. 2066 2067- CONFIG_FLASH_SHOW_PROGRESS 2068 If defined (must be an integer), print out countdown 2069 digits and dots. Recommended value: 45 (9..1) for 80 2070 column displays, 15 (3..1) for 40 column displays. 2071 2072- CFG_RX_ETH_BUFFER: 2073 Defines the number of ethernet receive buffers. On some 2074 ethernet controllers it is recommended to set this value 2075 to 8 or even higher (EEPRO100 or 405 EMAC), since all 2076 buffers can be full shortly after enabling the interface 2077 on high ethernet traffic. 2078 Defaults to 4 if not defined. 2079 2080The following definitions that deal with the placement and management 2081of environment data (variable area); in general, we support the 2082following configurations: 2083 2084- CFG_ENV_IS_IN_FLASH: 2085 2086 Define this if the environment is in flash memory. 2087 2088 a) The environment occupies one whole flash sector, which is 2089 "embedded" in the text segment with the U-Boot code. This 2090 happens usually with "bottom boot sector" or "top boot 2091 sector" type flash chips, which have several smaller 2092 sectors at the start or the end. For instance, such a 2093 layout can have sector sizes of 8, 2x4, 16, Nx32 kB. In 2094 such a case you would place the environment in one of the 2095 4 kB sectors - with U-Boot code before and after it. With 2096 "top boot sector" type flash chips, you would put the 2097 environment in one of the last sectors, leaving a gap 2098 between U-Boot and the environment. 2099 2100 - CFG_ENV_OFFSET: 2101 2102 Offset of environment data (variable area) to the 2103 beginning of flash memory; for instance, with bottom boot 2104 type flash chips the second sector can be used: the offset 2105 for this sector is given here. 2106 2107 CFG_ENV_OFFSET is used relative to CFG_FLASH_BASE. 2108 2109 - CFG_ENV_ADDR: 2110 2111 This is just another way to specify the start address of 2112 the flash sector containing the environment (instead of 2113 CFG_ENV_OFFSET). 2114 2115 - CFG_ENV_SECT_SIZE: 2116 2117 Size of the sector containing the environment. 2118 2119 2120 b) Sometimes flash chips have few, equal sized, BIG sectors. 2121 In such a case you don't want to spend a whole sector for 2122 the environment. 2123 2124 - CFG_ENV_SIZE: 2125 2126 If you use this in combination with CFG_ENV_IS_IN_FLASH 2127 and CFG_ENV_SECT_SIZE, you can specify to use only a part 2128 of this flash sector for the environment. This saves 2129 memory for the RAM copy of the environment. 2130 2131 It may also save flash memory if you decide to use this 2132 when your environment is "embedded" within U-Boot code, 2133 since then the remainder of the flash sector could be used 2134 for U-Boot code. It should be pointed out that this is 2135 STRONGLY DISCOURAGED from a robustness point of view: 2136 updating the environment in flash makes it always 2137 necessary to erase the WHOLE sector. If something goes 2138 wrong before the contents has been restored from a copy in 2139 RAM, your target system will be dead. 2140 2141 - CFG_ENV_ADDR_REDUND 2142 CFG_ENV_SIZE_REDUND 2143 2144 These settings describe a second storage area used to hold 2145 a redundand copy of the environment data, so that there is 2146 a valid backup copy in case there is a power failure during 2147 a "saveenv" operation. 2148 2149BE CAREFUL! Any changes to the flash layout, and some changes to the 2150source code will make it necessary to adapt <board>/u-boot.lds* 2151accordingly! 2152 2153 2154- CFG_ENV_IS_IN_NVRAM: 2155 2156 Define this if you have some non-volatile memory device 2157 (NVRAM, battery buffered SRAM) which you want to use for the 2158 environment. 2159 2160 - CFG_ENV_ADDR: 2161 - CFG_ENV_SIZE: 2162 2163 These two #defines are used to determin the memory area you 2164 want to use for environment. It is assumed that this memory 2165 can just be read and written to, without any special 2166 provision. 2167 2168BE CAREFUL! The first access to the environment happens quite early 2169in U-Boot initalization (when we try to get the setting of for the 2170console baudrate). You *MUST* have mappend your NVRAM area then, or 2171U-Boot will hang. 2172 2173Please note that even with NVRAM we still use a copy of the 2174environment in RAM: we could work on NVRAM directly, but we want to 2175keep settings there always unmodified except somebody uses "saveenv" 2176to save the current settings. 2177 2178 2179- CFG_ENV_IS_IN_EEPROM: 2180 2181 Use this if you have an EEPROM or similar serial access 2182 device and a driver for it. 2183 2184 - CFG_ENV_OFFSET: 2185 - CFG_ENV_SIZE: 2186 2187 These two #defines specify the offset and size of the 2188 environment area within the total memory of your EEPROM. 2189 2190 - CFG_I2C_EEPROM_ADDR: 2191 If defined, specified the chip address of the EEPROM device. 2192 The default address is zero. 2193 2194 - CFG_EEPROM_PAGE_WRITE_BITS: 2195 If defined, the number of bits used to address bytes in a 2196 single page in the EEPROM device. A 64 byte page, for example 2197 would require six bits. 2198 2199 - CFG_EEPROM_PAGE_WRITE_DELAY_MS: 2200 If defined, the number of milliseconds to delay between 2201 page writes. The default is zero milliseconds. 2202 2203 - CFG_I2C_EEPROM_ADDR_LEN: 2204 The length in bytes of the EEPROM memory array address. Note 2205 that this is NOT the chip address length! 2206 2207 - CFG_I2C_EEPROM_ADDR_OVERFLOW: 2208 EEPROM chips that implement "address overflow" are ones 2209 like Catalyst 24WC04/08/16 which has 9/10/11 bits of 2210 address and the extra bits end up in the "chip address" bit 2211 slots. This makes a 24WC08 (1Kbyte) chip look like four 256 2212 byte chips. 2213 2214 Note that we consider the length of the address field to 2215 still be one byte because the extra address bits are hidden 2216 in the chip address. 2217 2218 - CFG_EEPROM_SIZE: 2219 The size in bytes of the EEPROM device. 2220 2221 2222- CFG_ENV_IS_IN_DATAFLASH: 2223 2224 Define this if you have a DataFlash memory device which you 2225 want to use for the environment. 2226 2227 - CFG_ENV_OFFSET: 2228 - CFG_ENV_ADDR: 2229 - CFG_ENV_SIZE: 2230 2231 These three #defines specify the offset and size of the 2232 environment area within the total memory of your DataFlash placed 2233 at the specified address. 2234 2235- CFG_ENV_IS_IN_NAND: 2236 2237 Define this if you have a NAND device which you want to use 2238 for the environment. 2239 2240 - CFG_ENV_OFFSET: 2241 - CFG_ENV_SIZE: 2242 2243 These two #defines specify the offset and size of the environment 2244 area within the first NAND device. 2245 2246 - CFG_ENV_OFFSET_REDUND 2247 2248 This setting describes a second storage area of CFG_ENV_SIZE 2249 size used to hold a redundant copy of the environment data, 2250 so that there is a valid backup copy in case there is a 2251 power failure during a "saveenv" operation. 2252 2253 Note: CFG_ENV_OFFSET and CFG_ENV_OFFSET_REDUND must be aligned 2254 to a block boundary, and CFG_ENV_SIZE must be a multiple of 2255 the NAND devices block size. 2256 2257- CFG_SPI_INIT_OFFSET 2258 2259 Defines offset to the initial SPI buffer area in DPRAM. The 2260 area is used at an early stage (ROM part) if the environment 2261 is configured to reside in the SPI EEPROM: We need a 520 byte 2262 scratch DPRAM area. It is used between the two initialization 2263 calls (spi_init_f() and spi_init_r()). A value of 0xB00 seems 2264 to be a good choice since it makes it far enough from the 2265 start of the data area as well as from the stack pointer. 2266 2267Please note that the environment is read-only until the monitor 2268has been relocated to RAM and a RAM copy of the environment has been 2269created; also, when using EEPROM you will have to use getenv_r() 2270until then to read environment variables. 2271 2272The environment is protected by a CRC32 checksum. Before the monitor 2273is relocated into RAM, as a result of a bad CRC you will be working 2274with the compiled-in default environment - *silently*!!! [This is 2275necessary, because the first environment variable we need is the 2276"baudrate" setting for the console - if we have a bad CRC, we don't 2277have any device yet where we could complain.] 2278 2279Note: once the monitor has been relocated, then it will complain if 2280the default environment is used; a new CRC is computed as soon as you 2281use the "saveenv" command to store a valid environment. 2282 2283- CFG_FAULT_ECHO_LINK_DOWN: 2284 Echo the inverted Ethernet link state to the fault LED. 2285 2286 Note: If this option is active, then CFG_FAULT_MII_ADDR 2287 also needs to be defined. 2288 2289- CFG_FAULT_MII_ADDR: 2290 MII address of the PHY to check for the Ethernet link state. 2291 2292- CFG_64BIT_VSPRINTF: 2293 Makes vsprintf (and all *printf functions) support printing 2294 of 64bit values by using the L quantifier 2295 2296- CFG_64BIT_STRTOUL: 2297 Adds simple_strtoull that returns a 64bit value 2298 2299Low Level (hardware related) configuration options: 2300--------------------------------------------------- 2301 2302- CFG_CACHELINE_SIZE: 2303 Cache Line Size of the CPU. 2304 2305- CFG_DEFAULT_IMMR: 2306 Default address of the IMMR after system reset. 2307 2308 Needed on some 8260 systems (MPC8260ADS, PQ2FADS-ZU, 2309 and RPXsuper) to be able to adjust the position of 2310 the IMMR register after a reset. 2311 2312- Floppy Disk Support: 2313 CFG_FDC_DRIVE_NUMBER 2314 2315 the default drive number (default value 0) 2316 2317 CFG_ISA_IO_STRIDE 2318 2319 defines the spacing between fdc chipset registers 2320 (default value 1) 2321 2322 CFG_ISA_IO_OFFSET 2323 2324 defines the offset of register from address. It 2325 depends on which part of the data bus is connected to 2326 the fdc chipset. (default value 0) 2327 2328 If CFG_ISA_IO_STRIDE CFG_ISA_IO_OFFSET and 2329 CFG_FDC_DRIVE_NUMBER are undefined, they take their 2330 default value. 2331 2332 if CFG_FDC_HW_INIT is defined, then the function 2333 fdc_hw_init() is called at the beginning of the FDC 2334 setup. fdc_hw_init() must be provided by the board 2335 source code. It is used to make hardware dependant 2336 initializations. 2337 2338- CFG_IMMR: Physical address of the Internal Memory. 2339 DO NOT CHANGE unless you know exactly what you're 2340 doing! (11-4) [MPC8xx/82xx systems only] 2341 2342- CFG_INIT_RAM_ADDR: 2343 2344 Start address of memory area that can be used for 2345 initial data and stack; please note that this must be 2346 writable memory that is working WITHOUT special 2347 initialization, i. e. you CANNOT use normal RAM which 2348 will become available only after programming the 2349 memory controller and running certain initialization 2350 sequences. 2351 2352 U-Boot uses the following memory types: 2353 - MPC8xx and MPC8260: IMMR (internal memory of the CPU) 2354 - MPC824X: data cache 2355 - PPC4xx: data cache 2356 2357- CFG_GBL_DATA_OFFSET: 2358 2359 Offset of the initial data structure in the memory 2360 area defined by CFG_INIT_RAM_ADDR. Usually 2361 CFG_GBL_DATA_OFFSET is chosen such that the initial 2362 data is located at the end of the available space 2363 (sometimes written as (CFG_INIT_RAM_END - 2364 CFG_INIT_DATA_SIZE), and the initial stack is just 2365 below that area (growing from (CFG_INIT_RAM_ADDR + 2366 CFG_GBL_DATA_OFFSET) downward. 2367 2368 Note: 2369 On the MPC824X (or other systems that use the data 2370 cache for initial memory) the address chosen for 2371 CFG_INIT_RAM_ADDR is basically arbitrary - it must 2372 point to an otherwise UNUSED address space between 2373 the top of RAM and the start of the PCI space. 2374 2375- CFG_SIUMCR: SIU Module Configuration (11-6) 2376 2377- CFG_SYPCR: System Protection Control (11-9) 2378 2379- CFG_TBSCR: Time Base Status and Control (11-26) 2380 2381- CFG_PISCR: Periodic Interrupt Status and Control (11-31) 2382 2383- CFG_PLPRCR: PLL, Low-Power, and Reset Control Register (15-30) 2384 2385- CFG_SCCR: System Clock and reset Control Register (15-27) 2386 2387- CFG_OR_TIMING_SDRAM: 2388 SDRAM timing 2389 2390- CFG_MAMR_PTA: 2391 periodic timer for refresh 2392 2393- CFG_DER: Debug Event Register (37-47) 2394 2395- FLASH_BASE0_PRELIM, FLASH_BASE1_PRELIM, CFG_REMAP_OR_AM, 2396 CFG_PRELIM_OR_AM, CFG_OR_TIMING_FLASH, CFG_OR0_REMAP, 2397 CFG_OR0_PRELIM, CFG_BR0_PRELIM, CFG_OR1_REMAP, CFG_OR1_PRELIM, 2398 CFG_BR1_PRELIM: 2399 Memory Controller Definitions: BR0/1 and OR0/1 (FLASH) 2400 2401- SDRAM_BASE2_PRELIM, SDRAM_BASE3_PRELIM, SDRAM_MAX_SIZE, 2402 CFG_OR_TIMING_SDRAM, CFG_OR2_PRELIM, CFG_BR2_PRELIM, 2403 CFG_OR3_PRELIM, CFG_BR3_PRELIM: 2404 Memory Controller Definitions: BR2/3 and OR2/3 (SDRAM) 2405 2406- CFG_MAMR_PTA, CFG_MPTPR_2BK_4K, CFG_MPTPR_1BK_4K, CFG_MPTPR_2BK_8K, 2407 CFG_MPTPR_1BK_8K, CFG_MAMR_8COL, CFG_MAMR_9COL: 2408 Machine Mode Register and Memory Periodic Timer 2409 Prescaler definitions (SDRAM timing) 2410 2411- CFG_I2C_UCODE_PATCH, CFG_I2C_DPMEM_OFFSET [0x1FC0]: 2412 enable I2C microcode relocation patch (MPC8xx); 2413 define relocation offset in DPRAM [DSP2] 2414 2415- CFG_SMC_UCODE_PATCH, CFG_SMC_DPMEM_OFFSET [0x1FC0]: 2416 enable SMC microcode relocation patch (MPC8xx); 2417 define relocation offset in DPRAM [SMC1] 2418 2419- CFG_SPI_UCODE_PATCH, CFG_SPI_DPMEM_OFFSET [0x1FC0]: 2420 enable SPI microcode relocation patch (MPC8xx); 2421 define relocation offset in DPRAM [SCC4] 2422 2423- CFG_USE_OSCCLK: 2424 Use OSCM clock mode on MBX8xx board. Be careful, 2425 wrong setting might damage your board. Read 2426 doc/README.MBX before setting this variable! 2427 2428- CFG_CPM_POST_WORD_ADDR: (MPC8xx, MPC8260 only) 2429 Offset of the bootmode word in DPRAM used by post 2430 (Power On Self Tests). This definition overrides 2431 #define'd default value in commproc.h resp. 2432 cpm_8260.h. 2433 2434- CFG_PCI_SLV_MEM_LOCAL, CFG_PCI_SLV_MEM_BUS, CFG_PICMR0_MASK_ATTRIB, 2435 CFG_PCI_MSTR0_LOCAL, CFG_PCIMSK0_MASK, CFG_PCI_MSTR1_LOCAL, 2436 CFG_PCIMSK1_MASK, CFG_PCI_MSTR_MEM_LOCAL, CFG_PCI_MSTR_MEM_BUS, 2437 CFG_CPU_PCI_MEM_START, CFG_PCI_MSTR_MEM_SIZE, CFG_POCMR0_MASK_ATTRIB, 2438 CFG_PCI_MSTR_MEMIO_LOCAL, CFG_PCI_MSTR_MEMIO_BUS, CPU_PCI_MEMIO_START, 2439 CFG_PCI_MSTR_MEMIO_SIZE, CFG_POCMR1_MASK_ATTRIB, CFG_PCI_MSTR_IO_LOCAL, 2440 CFG_PCI_MSTR_IO_BUS, CFG_CPU_PCI_IO_START, CFG_PCI_MSTR_IO_SIZE, 2441 CFG_POCMR2_MASK_ATTRIB: (MPC826x only) 2442 Overrides the default PCI memory map in cpu/mpc8260/pci.c if set. 2443 2444- CONFIG_SPD_EEPROM 2445 Get DDR timing information from an I2C EEPROM. Common 2446 with pluggable memory modules such as SODIMMs 2447 2448 SPD_EEPROM_ADDRESS 2449 I2C address of the SPD EEPROM 2450 2451- CFG_SPD_BUS_NUM 2452 If SPD EEPROM is on an I2C bus other than the first 2453 one, specify here. Note that the value must resolve 2454 to something your driver can deal with. 2455 2456- CFG_83XX_DDR_USES_CS0 2457 Only for 83xx systems. If specified, then DDR should 2458 be configured using CS0 and CS1 instead of CS2 and CS3. 2459 2460- CFG_83XX_DDR_USES_CS0 2461 Only for 83xx systems. If specified, then DDR should 2462 be configured using CS0 and CS1 instead of CS2 and CS3. 2463 2464- CONFIG_ETHER_ON_FEC[12] 2465 Define to enable FEC[12] on a 8xx series processor. 2466 2467- CONFIG_FEC[12]_PHY 2468 Define to the hardcoded PHY address which corresponds 2469 to the given FEC; i. e. 2470 #define CONFIG_FEC1_PHY 4 2471 means that the PHY with address 4 is connected to FEC1 2472 2473 When set to -1, means to probe for first available. 2474 2475- CONFIG_FEC[12]_PHY_NORXERR 2476 The PHY does not have a RXERR line (RMII only). 2477 (so program the FEC to ignore it). 2478 2479- CONFIG_RMII 2480 Enable RMII mode for all FECs. 2481 Note that this is a global option, we can't 2482 have one FEC in standard MII mode and another in RMII mode. 2483 2484- CONFIG_CRC32_VERIFY 2485 Add a verify option to the crc32 command. 2486 The syntax is: 2487 2488 => crc32 -v <address> <count> <crc32> 2489 2490 Where address/count indicate a memory area 2491 and crc32 is the correct crc32 which the 2492 area should have. 2493 2494- CONFIG_LOOPW 2495 Add the "loopw" memory command. This only takes effect if 2496 the memory commands are activated globally (CONFIG_CMD_MEM). 2497 2498- CONFIG_MX_CYCLIC 2499 Add the "mdc" and "mwc" memory commands. These are cyclic 2500 "md/mw" commands. 2501 Examples: 2502 2503 => mdc.b 10 4 500 2504 This command will print 4 bytes (10,11,12,13) each 500 ms. 2505 2506 => mwc.l 100 12345678 10 2507 This command will write 12345678 to address 100 all 10 ms. 2508 2509 This only takes effect if the memory commands are activated 2510 globally (CONFIG_CMD_MEM). 2511 2512- CONFIG_SKIP_LOWLEVEL_INIT 2513- CONFIG_SKIP_RELOCATE_UBOOT 2514 2515 [ARM only] If these variables are defined, then 2516 certain low level initializations (like setting up 2517 the memory controller) are omitted and/or U-Boot does 2518 not relocate itself into RAM. 2519 Normally these variables MUST NOT be defined. The 2520 only exception is when U-Boot is loaded (to RAM) by 2521 some other boot loader or by a debugger which 2522 performs these intializations itself. 2523 2524 2525Building the Software: 2526====================== 2527 2528Building U-Boot has been tested in several native build environments 2529and in many different cross environments. Of course we cannot support 2530all possibly existing versions of cross development tools in all 2531(potentially obsolete) versions. In case of tool chain problems we 2532recommend to use the ELDK (see http://www.denx.de/wiki/DULG/ELDK) 2533which is extensively used to build and test U-Boot. 2534 2535If you are not using a native environment, it is assumed that you 2536have GNU cross compiling tools available in your path. In this case, 2537you must set the environment variable CROSS_COMPILE in your shell. 2538Note that no changes to the Makefile or any other source files are 2539necessary. For example using the ELDK on a 4xx CPU, please enter: 2540 2541 $ CROSS_COMPILE=ppc_4xx- 2542 $ export CROSS_COMPILE 2543 2544U-Boot is intended to be simple to build. After installing the 2545sources you must configure U-Boot for one specific board type. This 2546is done by typing: 2547 2548 make NAME_config 2549 2550where "NAME_config" is the name of one of the existing configu- 2551rations; see the main Makefile for supported names. 2552 2553Note: for some board special configuration names may exist; check if 2554 additional information is available from the board vendor; for 2555 instance, the TQM823L systems are available without (standard) 2556 or with LCD support. You can select such additional "features" 2557 when chosing the configuration, i. e. 2558 2559 make TQM823L_config 2560 - will configure for a plain TQM823L, i. e. no LCD support 2561 2562 make TQM823L_LCD_config 2563 - will configure for a TQM823L with U-Boot console on LCD 2564 2565 etc. 2566 2567 2568Finally, type "make all", and you should get some working U-Boot 2569images ready for download to / installation on your system: 2570 2571- "u-boot.bin" is a raw binary image 2572- "u-boot" is an image in ELF binary format 2573- "u-boot.srec" is in Motorola S-Record format 2574 2575By default the build is performed locally and the objects are saved 2576in the source directory. One of the two methods can be used to change 2577this behavior and build U-Boot to some external directory: 2578 25791. Add O= to the make command line invocations: 2580 2581 make O=/tmp/build distclean 2582 make O=/tmp/build NAME_config 2583 make O=/tmp/build all 2584 25852. Set environment variable BUILD_DIR to point to the desired location: 2586 2587 export BUILD_DIR=/tmp/build 2588 make distclean 2589 make NAME_config 2590 make all 2591 2592Note that the command line "O=" setting overrides the BUILD_DIR environment 2593variable. 2594 2595 2596Please be aware that the Makefiles assume you are using GNU make, so 2597for instance on NetBSD you might need to use "gmake" instead of 2598native "make". 2599 2600 2601If the system board that you have is not listed, then you will need 2602to port U-Boot to your hardware platform. To do this, follow these 2603steps: 2604 26051. Add a new configuration option for your board to the toplevel 2606 "Makefile" and to the "MAKEALL" script, using the existing 2607 entries as examples. Note that here and at many other places 2608 boards and other names are listed in alphabetical sort order. Please 2609 keep this order. 26102. Create a new directory to hold your board specific code. Add any 2611 files you need. In your board directory, you will need at least 2612 the "Makefile", a "<board>.c", "flash.c" and "u-boot.lds". 26133. Create a new configuration file "include/configs/<board>.h" for 2614 your board 26153. If you're porting U-Boot to a new CPU, then also create a new 2616 directory to hold your CPU specific code. Add any files you need. 26174. Run "make <board>_config" with your new name. 26185. Type "make", and you should get a working "u-boot.srec" file 2619 to be installed on your target system. 26206. Debug and solve any problems that might arise. 2621 [Of course, this last step is much harder than it sounds.] 2622 2623 2624Testing of U-Boot Modifications, Ports to New Hardware, etc.: 2625============================================================== 2626 2627If you have modified U-Boot sources (for instance added a new board 2628or support for new devices, a new CPU, etc.) you are expected to 2629provide feedback to the other developers. The feedback normally takes 2630the form of a "patch", i. e. a context diff against a certain (latest 2631official or latest in the git repository) version of U-Boot sources. 2632 2633But before you submit such a patch, please verify that your modifi- 2634cation did not break existing code. At least make sure that *ALL* of 2635the supported boards compile WITHOUT ANY compiler warnings. To do so, 2636just run the "MAKEALL" script, which will configure and build U-Boot 2637for ALL supported system. Be warned, this will take a while. You can 2638select which (cross) compiler to use by passing a `CROSS_COMPILE' 2639environment variable to the script, i. e. to use the ELDK cross tools 2640you can type 2641 2642 CROSS_COMPILE=ppc_8xx- MAKEALL 2643 2644or to build on a native PowerPC system you can type 2645 2646 CROSS_COMPILE=' ' MAKEALL 2647 2648When using the MAKEALL script, the default behaviour is to build 2649U-Boot in the source directory. This location can be changed by 2650setting the BUILD_DIR environment variable. Also, for each target 2651built, the MAKEALL script saves two log files (<target>.ERR and 2652<target>.MAKEALL) in the <source dir>/LOG directory. This default 2653location can be changed by setting the MAKEALL_LOGDIR environment 2654variable. For example: 2655 2656 export BUILD_DIR=/tmp/build 2657 export MAKEALL_LOGDIR=/tmp/log 2658 CROSS_COMPILE=ppc_8xx- MAKEALL 2659 2660With the above settings build objects are saved in the /tmp/build, 2661log files are saved in the /tmp/log and the source tree remains clean 2662during the whole build process. 2663 2664 2665See also "U-Boot Porting Guide" below. 2666 2667 2668Monitor Commands - Overview: 2669============================ 2670 2671go - start application at address 'addr' 2672run - run commands in an environment variable 2673bootm - boot application image from memory 2674bootp - boot image via network using BootP/TFTP protocol 2675tftpboot- boot image via network using TFTP protocol 2676 and env variables "ipaddr" and "serverip" 2677 (and eventually "gatewayip") 2678rarpboot- boot image via network using RARP/TFTP protocol 2679diskboot- boot from IDE devicebootd - boot default, i.e., run 'bootcmd' 2680loads - load S-Record file over serial line 2681loadb - load binary file over serial line (kermit mode) 2682md - memory display 2683mm - memory modify (auto-incrementing) 2684nm - memory modify (constant address) 2685mw - memory write (fill) 2686cp - memory copy 2687cmp - memory compare 2688crc32 - checksum calculation 2689imd - i2c memory display 2690imm - i2c memory modify (auto-incrementing) 2691inm - i2c memory modify (constant address) 2692imw - i2c memory write (fill) 2693icrc32 - i2c checksum calculation 2694iprobe - probe to discover valid I2C chip addresses 2695iloop - infinite loop on address range 2696isdram - print SDRAM configuration information 2697sspi - SPI utility commands 2698base - print or set address offset 2699printenv- print environment variables 2700setenv - set environment variables 2701saveenv - save environment variables to persistent storage 2702protect - enable or disable FLASH write protection 2703erase - erase FLASH memory 2704flinfo - print FLASH memory information 2705bdinfo - print Board Info structure 2706iminfo - print header information for application image 2707coninfo - print console devices and informations 2708ide - IDE sub-system 2709loop - infinite loop on address range 2710loopw - infinite write loop on address range 2711mtest - simple RAM test 2712icache - enable or disable instruction cache 2713dcache - enable or disable data cache 2714reset - Perform RESET of the CPU 2715echo - echo args to console 2716version - print monitor version 2717help - print online help 2718? - alias for 'help' 2719 2720 2721Monitor Commands - Detailed Description: 2722======================================== 2723 2724TODO. 2725 2726For now: just type "help <command>". 2727 2728 2729Environment Variables: 2730====================== 2731 2732U-Boot supports user configuration using Environment Variables which 2733can be made persistent by saving to Flash memory. 2734 2735Environment Variables are set using "setenv", printed using 2736"printenv", and saved to Flash using "saveenv". Using "setenv" 2737without a value can be used to delete a variable from the 2738environment. As long as you don't save the environment you are 2739working with an in-memory copy. In case the Flash area containing the 2740environment is erased by accident, a default environment is provided. 2741 2742Some configuration options can be set using Environment Variables: 2743 2744 baudrate - see CONFIG_BAUDRATE 2745 2746 bootdelay - see CONFIG_BOOTDELAY 2747 2748 bootcmd - see CONFIG_BOOTCOMMAND 2749 2750 bootargs - Boot arguments when booting an RTOS image 2751 2752 bootfile - Name of the image to load with TFTP 2753 2754 bootm_low - Memory range available for image processing in the bootm 2755 command can be restricted. This variable is given as 2756 a hexadecimal number and defines lowest address allowed 2757 for use by the bootm command. See also "bootm_size" 2758 environment variable. Address defined by "bootm_low" is 2759 also the base of the initial memory mapping for the Linux 2760 kernel -- see the descripton of CFG_BOOTMAPSZ. 2761 2762 bootm_size - Memory range available for image processing in the bootm 2763 command can be restricted. This variable is given as 2764 a hexadecimal number and defines the size of the region 2765 allowed for use by the bootm command. See also "bootm_low" 2766 environment variable. 2767 2768 autoload - if set to "no" (any string beginning with 'n'), 2769 "bootp" will just load perform a lookup of the 2770 configuration from the BOOTP server, but not try to 2771 load any image using TFTP 2772 2773 autoscript - if set to "yes" commands like "loadb", "loady", 2774 "bootp", "tftpb", "rarpboot" and "nfs" will attempt 2775 to automatically run script images (by internally 2776 calling "autoscript"). 2777 2778 autoscript_uname - if script image is in a format (FIT) this 2779 variable is used to get script subimage unit name. 2780 2781 autostart - if set to "yes", an image loaded using the "bootp", 2782 "rarpboot", "tftpboot" or "diskboot" commands will 2783 be automatically started (by internally calling 2784 "bootm") 2785 2786 If set to "no", a standalone image passed to the 2787 "bootm" command will be copied to the load address 2788 (and eventually uncompressed), but NOT be started. 2789 This can be used to load and uncompress arbitrary 2790 data. 2791 2792 i2cfast - (PPC405GP|PPC405EP only) 2793 if set to 'y' configures Linux I2C driver for fast 2794 mode (400kHZ). This environment variable is used in 2795 initialization code. So, for changes to be effective 2796 it must be saved and board must be reset. 2797 2798 initrd_high - restrict positioning of initrd images: 2799 If this variable is not set, initrd images will be 2800 copied to the highest possible address in RAM; this 2801 is usually what you want since it allows for 2802 maximum initrd size. If for some reason you want to 2803 make sure that the initrd image is loaded below the 2804 CFG_BOOTMAPSZ limit, you can set this environment 2805 variable to a value of "no" or "off" or "0". 2806 Alternatively, you can set it to a maximum upper 2807 address to use (U-Boot will still check that it 2808 does not overwrite the U-Boot stack and data). 2809 2810 For instance, when you have a system with 16 MB 2811 RAM, and want to reserve 4 MB from use by Linux, 2812 you can do this by adding "mem=12M" to the value of 2813 the "bootargs" variable. However, now you must make 2814 sure that the initrd image is placed in the first 2815 12 MB as well - this can be done with 2816 2817 setenv initrd_high 00c00000 2818 2819 If you set initrd_high to 0xFFFFFFFF, this is an 2820 indication to U-Boot that all addresses are legal 2821 for the Linux kernel, including addresses in flash 2822 memory. In this case U-Boot will NOT COPY the 2823 ramdisk at all. This may be useful to reduce the 2824 boot time on your system, but requires that this 2825 feature is supported by your Linux kernel. 2826 2827 ipaddr - IP address; needed for tftpboot command 2828 2829 loadaddr - Default load address for commands like "bootp", 2830 "rarpboot", "tftpboot", "loadb" or "diskboot" 2831 2832 loads_echo - see CONFIG_LOADS_ECHO 2833 2834 serverip - TFTP server IP address; needed for tftpboot command 2835 2836 bootretry - see CONFIG_BOOT_RETRY_TIME 2837 2838 bootdelaykey - see CONFIG_AUTOBOOT_DELAY_STR 2839 2840 bootstopkey - see CONFIG_AUTOBOOT_STOP_STR 2841 2842 ethprime - When CONFIG_NET_MULTI is enabled controls which 2843 interface is used first. 2844 2845 ethact - When CONFIG_NET_MULTI is enabled controls which 2846 interface is currently active. For example you 2847 can do the following 2848 2849 => setenv ethact FEC ETHERNET 2850 => ping 192.168.0.1 # traffic sent on FEC ETHERNET 2851 => setenv ethact SCC ETHERNET 2852 => ping 10.0.0.1 # traffic sent on SCC ETHERNET 2853 2854 ethrotate - When set to "no" U-Boot does not go through all 2855 available network interfaces. 2856 It just stays at the currently selected interface. 2857 2858 netretry - When set to "no" each network operation will 2859 either succeed or fail without retrying. 2860 When set to "once" the network operation will 2861 fail when all the available network interfaces 2862 are tried once without success. 2863 Useful on scripts which control the retry operation 2864 themselves. 2865 2866 npe_ucode - see CONFIG_IXP4XX_NPE_EXT_UCOD 2867 if set load address for the npe microcode 2868 2869 tftpsrcport - If this is set, the value is used for TFTP's 2870 UDP source port. 2871 2872 tftpdstport - If this is set, the value is used for TFTP's UDP 2873 destination port instead of the Well Know Port 69. 2874 2875 vlan - When set to a value < 4095 the traffic over 2876 ethernet is encapsulated/received over 802.1q 2877 VLAN tagged frames. 2878 2879The following environment variables may be used and automatically 2880updated by the network boot commands ("bootp" and "rarpboot"), 2881depending the information provided by your boot server: 2882 2883 bootfile - see above 2884 dnsip - IP address of your Domain Name Server 2885 dnsip2 - IP address of your secondary Domain Name Server 2886 gatewayip - IP address of the Gateway (Router) to use 2887 hostname - Target hostname 2888 ipaddr - see above 2889 netmask - Subnet Mask 2890 rootpath - Pathname of the root filesystem on the NFS server 2891 serverip - see above 2892 2893 2894There are two special Environment Variables: 2895 2896 serial# - contains hardware identification information such 2897 as type string and/or serial number 2898 ethaddr - Ethernet address 2899 2900These variables can be set only once (usually during manufacturing of 2901the board). U-Boot refuses to delete or overwrite these variables 2902once they have been set once. 2903 2904 2905Further special Environment Variables: 2906 2907 ver - Contains the U-Boot version string as printed 2908 with the "version" command. This variable is 2909 readonly (see CONFIG_VERSION_VARIABLE). 2910 2911 2912Please note that changes to some configuration parameters may take 2913only effect after the next boot (yes, that's just like Windoze :-). 2914 2915 2916Command Line Parsing: 2917===================== 2918 2919There are two different command line parsers available with U-Boot: 2920the old "simple" one, and the much more powerful "hush" shell: 2921 2922Old, simple command line parser: 2923-------------------------------- 2924 2925- supports environment variables (through setenv / saveenv commands) 2926- several commands on one line, separated by ';' 2927- variable substitution using "... ${name} ..." syntax 2928- special characters ('$', ';') can be escaped by prefixing with '\', 2929 for example: 2930 setenv bootcmd bootm \${address} 2931- You can also escape text by enclosing in single apostrophes, for example: 2932 setenv addip 'setenv bootargs $bootargs ip=$ipaddr:$serverip:$gatewayip:$netmask:$hostname::off' 2933 2934Hush shell: 2935----------- 2936 2937- similar to Bourne shell, with control structures like 2938 if...then...else...fi, for...do...done; while...do...done, 2939 until...do...done, ... 2940- supports environment ("global") variables (through setenv / saveenv 2941 commands) and local shell variables (through standard shell syntax 2942 "name=value"); only environment variables can be used with "run" 2943 command 2944 2945General rules: 2946-------------- 2947 2948(1) If a command line (or an environment variable executed by a "run" 2949 command) contains several commands separated by semicolon, and 2950 one of these commands fails, then the remaining commands will be 2951 executed anyway. 2952 2953(2) If you execute several variables with one call to run (i. e. 2954 calling run with a list af variables as arguments), any failing 2955 command will cause "run" to terminate, i. e. the remaining 2956 variables are not executed. 2957 2958Note for Redundant Ethernet Interfaces: 2959======================================= 2960 2961Some boards come with redundant ethernet interfaces; U-Boot supports 2962such configurations and is capable of automatic selection of a 2963"working" interface when needed. MAC assignment works as follows: 2964 2965Network interfaces are numbered eth0, eth1, eth2, ... Corresponding 2966MAC addresses can be stored in the environment as "ethaddr" (=>eth0), 2967"eth1addr" (=>eth1), "eth2addr", ... 2968 2969If the network interface stores some valid MAC address (for instance 2970in SROM), this is used as default address if there is NO correspon- 2971ding setting in the environment; if the corresponding environment 2972variable is set, this overrides the settings in the card; that means: 2973 2974o If the SROM has a valid MAC address, and there is no address in the 2975 environment, the SROM's address is used. 2976 2977o If there is no valid address in the SROM, and a definition in the 2978 environment exists, then the value from the environment variable is 2979 used. 2980 2981o If both the SROM and the environment contain a MAC address, and 2982 both addresses are the same, this MAC address is used. 2983 2984o If both the SROM and the environment contain a MAC address, and the 2985 addresses differ, the value from the environment is used and a 2986 warning is printed. 2987 2988o If neither SROM nor the environment contain a MAC address, an error 2989 is raised. 2990 2991 2992Image Formats: 2993============== 2994 2995U-Boot is capable of booting (and performing other auxiliary operations on) 2996images in two formats: 2997 2998New uImage format (FIT) 2999----------------------- 3000 3001Flexible and powerful format based on Flattened Image Tree -- FIT (similar 3002to Flattened Device Tree). It allows the use of images with multiple 3003components (several kernels, ramdisks, etc.), with contents protected by 3004SHA1, MD5 or CRC32. More details are found in the doc/uImage.FIT directory. 3005 3006 3007Old uImage format 3008----------------- 3009 3010Old image format is based on binary files which can be basically anything, 3011preceded by a special header; see the definitions in include/image.h for 3012details; basically, the header defines the following image properties: 3013 3014* Target Operating System (Provisions for OpenBSD, NetBSD, FreeBSD, 3015 4.4BSD, Linux, SVR4, Esix, Solaris, Irix, SCO, Dell, NCR, VxWorks, 3016 LynxOS, pSOS, QNX, RTEMS, ARTOS; 3017 Currently supported: Linux, NetBSD, VxWorks, QNX, RTEMS, ARTOS, LynxOS). 3018* Target CPU Architecture (Provisions for Alpha, ARM, AVR32, Intel x86, 3019 IA64, MIPS, NIOS, PowerPC, IBM S390, SuperH, Sparc, Sparc 64 Bit; 3020 Currently supported: ARM, AVR32, Intel x86, MIPS, NIOS, PowerPC). 3021* Compression Type (uncompressed, gzip, bzip2) 3022* Load Address 3023* Entry Point 3024* Image Name 3025* Image Timestamp 3026 3027The header is marked by a special Magic Number, and both the header 3028and the data portions of the image are secured against corruption by 3029CRC32 checksums. 3030 3031 3032Linux Support: 3033============== 3034 3035Although U-Boot should support any OS or standalone application 3036easily, the main focus has always been on Linux during the design of 3037U-Boot. 3038 3039U-Boot includes many features that so far have been part of some 3040special "boot loader" code within the Linux kernel. Also, any 3041"initrd" images to be used are no longer part of one big Linux image; 3042instead, kernel and "initrd" are separate images. This implementation 3043serves several purposes: 3044 3045- the same features can be used for other OS or standalone 3046 applications (for instance: using compressed images to reduce the 3047 Flash memory footprint) 3048 3049- it becomes much easier to port new Linux kernel versions because 3050 lots of low-level, hardware dependent stuff are done by U-Boot 3051 3052- the same Linux kernel image can now be used with different "initrd" 3053 images; of course this also means that different kernel images can 3054 be run with the same "initrd". This makes testing easier (you don't 3055 have to build a new "zImage.initrd" Linux image when you just 3056 change a file in your "initrd"). Also, a field-upgrade of the 3057 software is easier now. 3058 3059 3060Linux HOWTO: 3061============ 3062 3063Porting Linux to U-Boot based systems: 3064--------------------------------------- 3065 3066U-Boot cannot save you from doing all the necessary modifications to 3067configure the Linux device drivers for use with your target hardware 3068(no, we don't intend to provide a full virtual machine interface to 3069Linux :-). 3070 3071But now you can ignore ALL boot loader code (in arch/ppc/mbxboot). 3072 3073Just make sure your machine specific header file (for instance 3074include/asm-ppc/tqm8xx.h) includes the same definition of the Board 3075Information structure as we define in include/u-boot.h, and make 3076sure that your definition of IMAP_ADDR uses the same value as your 3077U-Boot configuration in CFG_IMMR. 3078 3079 3080Configuring the Linux kernel: 3081----------------------------- 3082 3083No specific requirements for U-Boot. Make sure you have some root 3084device (initial ramdisk, NFS) for your target system. 3085 3086 3087Building a Linux Image: 3088----------------------- 3089 3090With U-Boot, "normal" build targets like "zImage" or "bzImage" are 3091not used. If you use recent kernel source, a new build target 3092"uImage" will exist which automatically builds an image usable by 3093U-Boot. Most older kernels also have support for a "pImage" target, 3094which was introduced for our predecessor project PPCBoot and uses a 3095100% compatible format. 3096 3097Example: 3098 3099 make TQM850L_config 3100 make oldconfig 3101 make dep 3102 make uImage 3103 3104The "uImage" build target uses a special tool (in 'tools/mkimage') to 3105encapsulate a compressed Linux kernel image with header information, 3106CRC32 checksum etc. for use with U-Boot. This is what we are doing: 3107 3108* build a standard "vmlinux" kernel image (in ELF binary format): 3109 3110* convert the kernel into a raw binary image: 3111 3112 ${CROSS_COMPILE}-objcopy -O binary \ 3113 -R .note -R .comment \ 3114 -S vmlinux linux.bin 3115 3116* compress the binary image: 3117 3118 gzip -9 linux.bin 3119 3120* package compressed binary image for U-Boot: 3121 3122 mkimage -A ppc -O linux -T kernel -C gzip \ 3123 -a 0 -e 0 -n "Linux Kernel Image" \ 3124 -d linux.bin.gz uImage 3125 3126 3127The "mkimage" tool can also be used to create ramdisk images for use 3128with U-Boot, either separated from the Linux kernel image, or 3129combined into one file. "mkimage" encapsulates the images with a 64 3130byte header containing information about target architecture, 3131operating system, image type, compression method, entry points, time 3132stamp, CRC32 checksums, etc. 3133 3134"mkimage" can be called in two ways: to verify existing images and 3135print the header information, or to build new images. 3136 3137In the first form (with "-l" option) mkimage lists the information 3138contained in the header of an existing U-Boot image; this includes 3139checksum verification: 3140 3141 tools/mkimage -l image 3142 -l ==> list image header information 3143 3144The second form (with "-d" option) is used to build a U-Boot image 3145from a "data file" which is used as image payload: 3146 3147 tools/mkimage -A arch -O os -T type -C comp -a addr -e ep \ 3148 -n name -d data_file image 3149 -A ==> set architecture to 'arch' 3150 -O ==> set operating system to 'os' 3151 -T ==> set image type to 'type' 3152 -C ==> set compression type 'comp' 3153 -a ==> set load address to 'addr' (hex) 3154 -e ==> set entry point to 'ep' (hex) 3155 -n ==> set image name to 'name' 3156 -d ==> use image data from 'datafile' 3157 3158Right now, all Linux kernels for PowerPC systems use the same load 3159address (0x00000000), but the entry point address depends on the 3160kernel version: 3161 3162- 2.2.x kernels have the entry point at 0x0000000C, 3163- 2.3.x and later kernels have the entry point at 0x00000000. 3164 3165So a typical call to build a U-Boot image would read: 3166 3167 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \ 3168 > -A ppc -O linux -T kernel -C gzip -a 0 -e 0 \ 3169 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/ppc/coffboot/vmlinux.gz \ 3170 > examples/uImage.TQM850L 3171 Image Name: 2.4.4 kernel for TQM850L 3172 Created: Wed Jul 19 02:34:59 2000 3173 Image Type: PowerPC Linux Kernel Image (gzip compressed) 3174 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB 3175 Load Address: 0x00000000 3176 Entry Point: 0x00000000 3177 3178To verify the contents of the image (or check for corruption): 3179 3180 -> tools/mkimage -l examples/uImage.TQM850L 3181 Image Name: 2.4.4 kernel for TQM850L 3182 Created: Wed Jul 19 02:34:59 2000 3183 Image Type: PowerPC Linux Kernel Image (gzip compressed) 3184 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB 3185 Load Address: 0x00000000 3186 Entry Point: 0x00000000 3187 3188NOTE: for embedded systems where boot time is critical you can trade 3189speed for memory and install an UNCOMPRESSED image instead: this 3190needs more space in Flash, but boots much faster since it does not 3191need to be uncompressed: 3192 3193 -> gunzip /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/ppc/coffboot/vmlinux.gz 3194 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \ 3195 > -A ppc -O linux -T kernel -C none -a 0 -e 0 \ 3196 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/ppc/coffboot/vmlinux \ 3197 > examples/uImage.TQM850L-uncompressed 3198 Image Name: 2.4.4 kernel for TQM850L 3199 Created: Wed Jul 19 02:34:59 2000 3200 Image Type: PowerPC Linux Kernel Image (uncompressed) 3201 Data Size: 792160 Bytes = 773.59 kB = 0.76 MB 3202 Load Address: 0x00000000 3203 Entry Point: 0x00000000 3204 3205 3206Similar you can build U-Boot images from a 'ramdisk.image.gz' file 3207when your kernel is intended to use an initial ramdisk: 3208 3209 -> tools/mkimage -n 'Simple Ramdisk Image' \ 3210 > -A ppc -O linux -T ramdisk -C gzip \ 3211 > -d /LinuxPPC/images/SIMPLE-ramdisk.image.gz examples/simple-initrd 3212 Image Name: Simple Ramdisk Image 3213 Created: Wed Jan 12 14:01:50 2000 3214 Image Type: PowerPC Linux RAMDisk Image (gzip compressed) 3215 Data Size: 566530 Bytes = 553.25 kB = 0.54 MB 3216 Load Address: 0x00000000 3217 Entry Point: 0x00000000 3218 3219 3220Installing a Linux Image: 3221------------------------- 3222 3223To downloading a U-Boot image over the serial (console) interface, 3224you must convert the image to S-Record format: 3225 3226 objcopy -I binary -O srec examples/image examples/image.srec 3227 3228The 'objcopy' does not understand the information in the U-Boot 3229image header, so the resulting S-Record file will be relative to 3230address 0x00000000. To load it to a given address, you need to 3231specify the target address as 'offset' parameter with the 'loads' 3232command. 3233 3234Example: install the image to address 0x40100000 (which on the 3235TQM8xxL is in the first Flash bank): 3236 3237 => erase 40100000 401FFFFF 3238 3239 .......... done 3240 Erased 8 sectors 3241 3242 => loads 40100000 3243 ## Ready for S-Record download ... 3244 ~>examples/image.srec 3245 1 2 3 4 5 6 7 8 9 10 11 12 13 ... 3246 ... 3247 15989 15990 15991 15992 3248 [file transfer complete] 3249 [connected] 3250 ## Start Addr = 0x00000000 3251 3252 3253You can check the success of the download using the 'iminfo' command; 3254this includes a checksum verification so you can be sure no data 3255corruption happened: 3256 3257 => imi 40100000 3258 3259 ## Checking Image at 40100000 ... 3260 Image Name: 2.2.13 for initrd on TQM850L 3261 Image Type: PowerPC Linux Kernel Image (gzip compressed) 3262 Data Size: 335725 Bytes = 327 kB = 0 MB 3263 Load Address: 00000000 3264 Entry Point: 0000000c 3265 Verifying Checksum ... OK 3266 3267 3268Boot Linux: 3269----------- 3270 3271The "bootm" command is used to boot an application that is stored in 3272memory (RAM or Flash). In case of a Linux kernel image, the contents 3273of the "bootargs" environment variable is passed to the kernel as 3274parameters. You can check and modify this variable using the 3275"printenv" and "setenv" commands: 3276 3277 3278 => printenv bootargs 3279 bootargs=root=/dev/ram 3280 3281 => setenv bootargs root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2 3282 3283 => printenv bootargs 3284 bootargs=root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2 3285 3286 => bootm 40020000 3287 ## Booting Linux kernel at 40020000 ... 3288 Image Name: 2.2.13 for NFS on TQM850L 3289 Image Type: PowerPC Linux Kernel Image (gzip compressed) 3290 Data Size: 381681 Bytes = 372 kB = 0 MB 3291 Load Address: 00000000 3292 Entry Point: 0000000c 3293 Verifying Checksum ... OK 3294 Uncompressing Kernel Image ... OK 3295 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 3296 Boot arguments: root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2 3297 time_init: decrementer frequency = 187500000/60 3298 Calibrating delay loop... 49.77 BogoMIPS 3299 Memory: 15208k available (700k kernel code, 444k data, 32k init) [c0000000,c1000000] 3300 ... 3301 3302If you want to boot a Linux kernel with initial ram disk, you pass 3303the memory addresses of both the kernel and the initrd image (PPBCOOT 3304format!) to the "bootm" command: 3305 3306 => imi 40100000 40200000 3307 3308 ## Checking Image at 40100000 ... 3309 Image Name: 2.2.13 for initrd on TQM850L 3310 Image Type: PowerPC Linux Kernel Image (gzip compressed) 3311 Data Size: 335725 Bytes = 327 kB = 0 MB 3312 Load Address: 00000000 3313 Entry Point: 0000000c 3314 Verifying Checksum ... OK 3315 3316 ## Checking Image at 40200000 ... 3317 Image Name: Simple Ramdisk Image 3318 Image Type: PowerPC Linux RAMDisk Image (gzip compressed) 3319 Data Size: 566530 Bytes = 553 kB = 0 MB 3320 Load Address: 00000000 3321 Entry Point: 00000000 3322 Verifying Checksum ... OK 3323 3324 => bootm 40100000 40200000 3325 ## Booting Linux kernel at 40100000 ... 3326 Image Name: 2.2.13 for initrd on TQM850L 3327 Image Type: PowerPC Linux Kernel Image (gzip compressed) 3328 Data Size: 335725 Bytes = 327 kB = 0 MB 3329 Load Address: 00000000 3330 Entry Point: 0000000c 3331 Verifying Checksum ... OK 3332 Uncompressing Kernel Image ... OK 3333 ## Loading RAMDisk Image at 40200000 ... 3334 Image Name: Simple Ramdisk Image 3335 Image Type: PowerPC Linux RAMDisk Image (gzip compressed) 3336 Data Size: 566530 Bytes = 553 kB = 0 MB 3337 Load Address: 00000000 3338 Entry Point: 00000000 3339 Verifying Checksum ... OK 3340 Loading Ramdisk ... OK 3341 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 3342 Boot arguments: root=/dev/ram 3343 time_init: decrementer frequency = 187500000/60 3344 Calibrating delay loop... 49.77 BogoMIPS 3345 ... 3346 RAMDISK: Compressed image found at block 0 3347 VFS: Mounted root (ext2 filesystem). 3348 3349 bash# 3350 3351Boot Linux and pass a flat device tree: 3352----------- 3353 3354First, U-Boot must be compiled with the appropriate defines. See the section 3355titled "Linux Kernel Interface" above for a more in depth explanation. The 3356following is an example of how to start a kernel and pass an updated 3357flat device tree: 3358 3359=> print oftaddr 3360oftaddr=0x300000 3361=> print oft 3362oft=oftrees/mpc8540ads.dtb 3363=> tftp $oftaddr $oft 3364Speed: 1000, full duplex 3365Using TSEC0 device 3366TFTP from server 192.168.1.1; our IP address is 192.168.1.101 3367Filename 'oftrees/mpc8540ads.dtb'. 3368Load address: 0x300000 3369Loading: # 3370done 3371Bytes transferred = 4106 (100a hex) 3372=> tftp $loadaddr $bootfile 3373Speed: 1000, full duplex 3374Using TSEC0 device 3375TFTP from server 192.168.1.1; our IP address is 192.168.1.2 3376Filename 'uImage'. 3377Load address: 0x200000 3378Loading:############ 3379done 3380Bytes transferred = 1029407 (fb51f hex) 3381=> print loadaddr 3382loadaddr=200000 3383=> print oftaddr 3384oftaddr=0x300000 3385=> bootm $loadaddr - $oftaddr 3386## Booting image at 00200000 ... 3387 Image Name: Linux-2.6.17-dirty 3388 Image Type: PowerPC Linux Kernel Image (gzip compressed) 3389 Data Size: 1029343 Bytes = 1005.2 kB 3390 Load Address: 00000000 3391 Entry Point: 00000000 3392 Verifying Checksum ... OK 3393 Uncompressing Kernel Image ... OK 3394Booting using flat device tree at 0x300000 3395Using MPC85xx ADS machine description 3396Memory CAM mapping: CAM0=256Mb, CAM1=256Mb, CAM2=0Mb residual: 0Mb 3397[snip] 3398 3399 3400More About U-Boot Image Types: 3401------------------------------ 3402 3403U-Boot supports the following image types: 3404 3405 "Standalone Programs" are directly runnable in the environment 3406 provided by U-Boot; it is expected that (if they behave 3407 well) you can continue to work in U-Boot after return from 3408 the Standalone Program. 3409 "OS Kernel Images" are usually images of some Embedded OS which 3410 will take over control completely. Usually these programs 3411 will install their own set of exception handlers, device 3412 drivers, set up the MMU, etc. - this means, that you cannot 3413 expect to re-enter U-Boot except by resetting the CPU. 3414 "RAMDisk Images" are more or less just data blocks, and their 3415 parameters (address, size) are passed to an OS kernel that is 3416 being started. 3417 "Multi-File Images" contain several images, typically an OS 3418 (Linux) kernel image and one or more data images like 3419 RAMDisks. This construct is useful for instance when you want 3420 to boot over the network using BOOTP etc., where the boot 3421 server provides just a single image file, but you want to get 3422 for instance an OS kernel and a RAMDisk image. 3423 3424 "Multi-File Images" start with a list of image sizes, each 3425 image size (in bytes) specified by an "uint32_t" in network 3426 byte order. This list is terminated by an "(uint32_t)0". 3427 Immediately after the terminating 0 follow the images, one by 3428 one, all aligned on "uint32_t" boundaries (size rounded up to 3429 a multiple of 4 bytes). 3430 3431 "Firmware Images" are binary images containing firmware (like 3432 U-Boot or FPGA images) which usually will be programmed to 3433 flash memory. 3434 3435 "Script files" are command sequences that will be executed by 3436 U-Boot's command interpreter; this feature is especially 3437 useful when you configure U-Boot to use a real shell (hush) 3438 as command interpreter. 3439 3440 3441Standalone HOWTO: 3442================= 3443 3444One of the features of U-Boot is that you can dynamically load and 3445run "standalone" applications, which can use some resources of 3446U-Boot like console I/O functions or interrupt services. 3447 3448Two simple examples are included with the sources: 3449 3450"Hello World" Demo: 3451------------------- 3452 3453'examples/hello_world.c' contains a small "Hello World" Demo 3454application; it is automatically compiled when you build U-Boot. 3455It's configured to run at address 0x00040004, so you can play with it 3456like that: 3457 3458 => loads 3459 ## Ready for S-Record download ... 3460 ~>examples/hello_world.srec 3461 1 2 3 4 5 6 7 8 9 10 11 ... 3462 [file transfer complete] 3463 [connected] 3464 ## Start Addr = 0x00040004 3465 3466 => go 40004 Hello World! This is a test. 3467 ## Starting application at 0x00040004 ... 3468 Hello World 3469 argc = 7 3470 argv[0] = "40004" 3471 argv[1] = "Hello" 3472 argv[2] = "World!" 3473 argv[3] = "This" 3474 argv[4] = "is" 3475 argv[5] = "a" 3476 argv[6] = "test." 3477 argv[7] = "<NULL>" 3478 Hit any key to exit ... 3479 3480 ## Application terminated, rc = 0x0 3481 3482Another example, which demonstrates how to register a CPM interrupt 3483handler with the U-Boot code, can be found in 'examples/timer.c'. 3484Here, a CPM timer is set up to generate an interrupt every second. 3485The interrupt service routine is trivial, just printing a '.' 3486character, but this is just a demo program. The application can be 3487controlled by the following keys: 3488 3489 ? - print current values og the CPM Timer registers 3490 b - enable interrupts and start timer 3491 e - stop timer and disable interrupts 3492 q - quit application 3493 3494 => loads 3495 ## Ready for S-Record download ... 3496 ~>examples/timer.srec 3497 1 2 3 4 5 6 7 8 9 10 11 ... 3498 [file transfer complete] 3499 [connected] 3500 ## Start Addr = 0x00040004 3501 3502 => go 40004 3503 ## Starting application at 0x00040004 ... 3504 TIMERS=0xfff00980 3505 Using timer 1 3506 tgcr @ 0xfff00980, tmr @ 0xfff00990, trr @ 0xfff00994, tcr @ 0xfff00998, tcn @ 0xfff0099c, ter @ 0xfff009b0 3507 3508Hit 'b': 3509 [q, b, e, ?] Set interval 1000000 us 3510 Enabling timer 3511Hit '?': 3512 [q, b, e, ?] ........ 3513 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0xef6, ter=0x0 3514Hit '?': 3515 [q, b, e, ?] . 3516 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x2ad4, ter=0x0 3517Hit '?': 3518 [q, b, e, ?] . 3519 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x1efc, ter=0x0 3520Hit '?': 3521 [q, b, e, ?] . 3522 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x169d, ter=0x0 3523Hit 'e': 3524 [q, b, e, ?] ...Stopping timer 3525Hit 'q': 3526 [q, b, e, ?] ## Application terminated, rc = 0x0 3527 3528 3529Minicom warning: 3530================ 3531 3532Over time, many people have reported problems when trying to use the 3533"minicom" terminal emulation program for serial download. I (wd) 3534consider minicom to be broken, and recommend not to use it. Under 3535Unix, I recommend to use C-Kermit for general purpose use (and 3536especially for kermit binary protocol download ("loadb" command), and 3537use "cu" for S-Record download ("loads" command). 3538 3539Nevertheless, if you absolutely want to use it try adding this 3540configuration to your "File transfer protocols" section: 3541 3542 Name Program Name U/D FullScr IO-Red. Multi 3543 X kermit /usr/bin/kermit -i -l %l -s Y U Y N N 3544 Y kermit /usr/bin/kermit -i -l %l -r N D Y N N 3545 3546 3547NetBSD Notes: 3548============= 3549 3550Starting at version 0.9.2, U-Boot supports NetBSD both as host 3551(build U-Boot) and target system (boots NetBSD/mpc8xx). 3552 3553Building requires a cross environment; it is known to work on 3554NetBSD/i386 with the cross-powerpc-netbsd-1.3 package (you will also 3555need gmake since the Makefiles are not compatible with BSD make). 3556Note that the cross-powerpc package does not install include files; 3557attempting to build U-Boot will fail because <machine/ansi.h> is 3558missing. This file has to be installed and patched manually: 3559 3560 # cd /usr/pkg/cross/powerpc-netbsd/include 3561 # mkdir powerpc 3562 # ln -s powerpc machine 3563 # cp /usr/src/sys/arch/powerpc/include/ansi.h powerpc/ansi.h 3564 # ${EDIT} powerpc/ansi.h ## must remove __va_list, _BSD_VA_LIST 3565 3566Native builds *don't* work due to incompatibilities between native 3567and U-Boot include files. 3568 3569Booting assumes that (the first part of) the image booted is a 3570stage-2 loader which in turn loads and then invokes the kernel 3571proper. Loader sources will eventually appear in the NetBSD source 3572tree (probably in sys/arc/mpc8xx/stand/u-boot_stage2/); in the 3573meantime, see ftp://ftp.denx.de/pub/u-boot/ppcboot_stage2.tar.gz 3574 3575 3576Implementation Internals: 3577========================= 3578 3579The following is not intended to be a complete description of every 3580implementation detail. However, it should help to understand the 3581inner workings of U-Boot and make it easier to port it to custom 3582hardware. 3583 3584 3585Initial Stack, Global Data: 3586--------------------------- 3587 3588The implementation of U-Boot is complicated by the fact that U-Boot 3589starts running out of ROM (flash memory), usually without access to 3590system RAM (because the memory controller is not initialized yet). 3591This means that we don't have writable Data or BSS segments, and BSS 3592is not initialized as zero. To be able to get a C environment working 3593at all, we have to allocate at least a minimal stack. Implementation 3594options for this are defined and restricted by the CPU used: Some CPU 3595models provide on-chip memory (like the IMMR area on MPC8xx and 3596MPC826x processors), on others (parts of) the data cache can be 3597locked as (mis-) used as memory, etc. 3598 3599 Chris Hallinan posted a good summary of these issues to the 3600 u-boot-users mailing list: 3601 3602 Subject: RE: [U-Boot-Users] RE: More On Memory Bank x (nothingness)? 3603 From: "Chris Hallinan" <clh@net1plus.com> 3604 Date: Mon, 10 Feb 2003 16:43:46 -0500 (22:43 MET) 3605 ... 3606 3607 Correct me if I'm wrong, folks, but the way I understand it 3608 is this: Using DCACHE as initial RAM for Stack, etc, does not 3609 require any physical RAM backing up the cache. The cleverness 3610 is that the cache is being used as a temporary supply of 3611 necessary storage before the SDRAM controller is setup. It's 3612 beyond the scope of this list to expain the details, but you 3613 can see how this works by studying the cache architecture and 3614 operation in the architecture and processor-specific manuals. 3615 3616 OCM is On Chip Memory, which I believe the 405GP has 4K. It 3617 is another option for the system designer to use as an 3618 initial stack/ram area prior to SDRAM being available. Either 3619 option should work for you. Using CS 4 should be fine if your 3620 board designers haven't used it for something that would 3621 cause you grief during the initial boot! It is frequently not 3622 used. 3623 3624 CFG_INIT_RAM_ADDR should be somewhere that won't interfere 3625 with your processor/board/system design. The default value 3626 you will find in any recent u-boot distribution in 3627 walnut.h should work for you. I'd set it to a value larger 3628 than your SDRAM module. If you have a 64MB SDRAM module, set 3629 it above 400_0000. Just make sure your board has no resources 3630 that are supposed to respond to that address! That code in 3631 start.S has been around a while and should work as is when 3632 you get the config right. 3633 3634 -Chris Hallinan 3635 DS4.COM, Inc. 3636 3637It is essential to remember this, since it has some impact on the C 3638code for the initialization procedures: 3639 3640* Initialized global data (data segment) is read-only. Do not attempt 3641 to write it. 3642 3643* Do not use any unitialized global data (or implicitely initialized 3644 as zero data - BSS segment) at all - this is undefined, initiali- 3645 zation is performed later (when relocating to RAM). 3646 3647* Stack space is very limited. Avoid big data buffers or things like 3648 that. 3649 3650Having only the stack as writable memory limits means we cannot use 3651normal global data to share information beween the code. But it 3652turned out that the implementation of U-Boot can be greatly 3653simplified by making a global data structure (gd_t) available to all 3654functions. We could pass a pointer to this data as argument to _all_ 3655functions, but this would bloat the code. Instead we use a feature of 3656the GCC compiler (Global Register Variables) to share the data: we 3657place a pointer (gd) to the global data into a register which we 3658reserve for this purpose. 3659 3660When choosing a register for such a purpose we are restricted by the 3661relevant (E)ABI specifications for the current architecture, and by 3662GCC's implementation. 3663 3664For PowerPC, the following registers have specific use: 3665 R1: stack pointer 3666 R2: reserved for system use 3667 R3-R4: parameter passing and return values 3668 R5-R10: parameter passing 3669 R13: small data area pointer 3670 R30: GOT pointer 3671 R31: frame pointer 3672 3673 (U-Boot also uses R14 as internal GOT pointer.) 3674 3675 ==> U-Boot will use R2 to hold a pointer to the global data 3676 3677 Note: on PPC, we could use a static initializer (since the 3678 address of the global data structure is known at compile time), 3679 but it turned out that reserving a register results in somewhat 3680 smaller code - although the code savings are not that big (on 3681 average for all boards 752 bytes for the whole U-Boot image, 3682 624 text + 127 data). 3683 3684On Blackfin, the normal C ABI (except for P5) is followed as documented here: 3685 http://docs.blackfin.uclinux.org/doku.php?id=application_binary_interface 3686 3687 ==> U-Boot will use P5 to hold a pointer to the global data 3688 3689On ARM, the following registers are used: 3690 3691 R0: function argument word/integer result 3692 R1-R3: function argument word 3693 R9: GOT pointer 3694 R10: stack limit (used only if stack checking if enabled) 3695 R11: argument (frame) pointer 3696 R12: temporary workspace 3697 R13: stack pointer 3698 R14: link register 3699 R15: program counter 3700 3701 ==> U-Boot will use R8 to hold a pointer to the global data 3702 3703NOTE: DECLARE_GLOBAL_DATA_PTR must be used with file-global scope, 3704or current versions of GCC may "optimize" the code too much. 3705 3706Memory Management: 3707------------------ 3708 3709U-Boot runs in system state and uses physical addresses, i.e. the 3710MMU is not used either for address mapping nor for memory protection. 3711 3712The available memory is mapped to fixed addresses using the memory 3713controller. In this process, a contiguous block is formed for each 3714memory type (Flash, SDRAM, SRAM), even when it consists of several 3715physical memory banks. 3716 3717U-Boot is installed in the first 128 kB of the first Flash bank (on 3718TQM8xxL modules this is the range 0x40000000 ... 0x4001FFFF). After 3719booting and sizing and initializing DRAM, the code relocates itself 3720to the upper end of DRAM. Immediately below the U-Boot code some 3721memory is reserved for use by malloc() [see CFG_MALLOC_LEN 3722configuration setting]. Below that, a structure with global Board 3723Info data is placed, followed by the stack (growing downward). 3724 3725Additionally, some exception handler code is copied to the low 8 kB 3726of DRAM (0x00000000 ... 0x00001FFF). 3727 3728So a typical memory configuration with 16 MB of DRAM could look like 3729this: 3730 3731 0x0000 0000 Exception Vector code 3732 : 3733 0x0000 1FFF 3734 0x0000 2000 Free for Application Use 3735 : 3736 : 3737 3738 : 3739 : 3740 0x00FB FF20 Monitor Stack (Growing downward) 3741 0x00FB FFAC Board Info Data and permanent copy of global data 3742 0x00FC 0000 Malloc Arena 3743 : 3744 0x00FD FFFF 3745 0x00FE 0000 RAM Copy of Monitor Code 3746 ... eventually: LCD or video framebuffer 3747 ... eventually: pRAM (Protected RAM - unchanged by reset) 3748 0x00FF FFFF [End of RAM] 3749 3750 3751System Initialization: 3752---------------------- 3753 3754In the reset configuration, U-Boot starts at the reset entry point 3755(on most PowerPC systens at address 0x00000100). Because of the reset 3756configuration for CS0# this is a mirror of the onboard Flash memory. 3757To be able to re-map memory U-Boot then jumps to its link address. 3758To be able to implement the initialization code in C, a (small!) 3759initial stack is set up in the internal Dual Ported RAM (in case CPUs 3760which provide such a feature like MPC8xx or MPC8260), or in a locked 3761part of the data cache. After that, U-Boot initializes the CPU core, 3762the caches and the SIU. 3763 3764Next, all (potentially) available memory banks are mapped using a 3765preliminary mapping. For example, we put them on 512 MB boundaries 3766(multiples of 0x20000000: SDRAM on 0x00000000 and 0x20000000, Flash 3767on 0x40000000 and 0x60000000, SRAM on 0x80000000). Then UPM A is 3768programmed for SDRAM access. Using the temporary configuration, a 3769simple memory test is run that determines the size of the SDRAM 3770banks. 3771 3772When there is more than one SDRAM bank, and the banks are of 3773different size, the largest is mapped first. For equal size, the first 3774bank (CS2#) is mapped first. The first mapping is always for address 37750x00000000, with any additional banks following immediately to create 3776contiguous memory starting from 0. 3777 3778Then, the monitor installs itself at the upper end of the SDRAM area 3779and allocates memory for use by malloc() and for the global Board 3780Info data; also, the exception vector code is copied to the low RAM 3781pages, and the final stack is set up. 3782 3783Only after this relocation will you have a "normal" C environment; 3784until that you are restricted in several ways, mostly because you are 3785running from ROM, and because the code will have to be relocated to a 3786new address in RAM. 3787 3788 3789U-Boot Porting Guide: 3790---------------------- 3791 3792[Based on messages by Jerry Van Baren in the U-Boot-Users mailing 3793list, October 2002] 3794 3795 3796int main (int argc, char *argv[]) 3797{ 3798 sighandler_t no_more_time; 3799 3800 signal (SIGALRM, no_more_time); 3801 alarm (PROJECT_DEADLINE - toSec (3 * WEEK)); 3802 3803 if (available_money > available_manpower) { 3804 pay consultant to port U-Boot; 3805 return 0; 3806 } 3807 3808 Download latest U-Boot source; 3809 3810 Subscribe to u-boot-users mailing list; 3811 3812 if (clueless) { 3813 email ("Hi, I am new to U-Boot, how do I get started?"); 3814 } 3815 3816 while (learning) { 3817 Read the README file in the top level directory; 3818 Read http://www.denx.de/twiki/bin/view/DULG/Manual ; 3819 Read the source, Luke; 3820 } 3821 3822 if (available_money > toLocalCurrency ($2500)) { 3823 Buy a BDI2000; 3824 } else { 3825 Add a lot of aggravation and time; 3826 } 3827 3828 Create your own board support subdirectory; 3829 3830 Create your own board config file; 3831 3832 while (!running) { 3833 do { 3834 Add / modify source code; 3835 } until (compiles); 3836 Debug; 3837 if (clueless) 3838 email ("Hi, I am having problems..."); 3839 } 3840 Send patch file to Wolfgang; 3841 3842 return 0; 3843} 3844 3845void no_more_time (int sig) 3846{ 3847 hire_a_guru(); 3848} 3849 3850 3851Coding Standards: 3852----------------- 3853 3854All contributions to U-Boot should conform to the Linux kernel 3855coding style; see the file "Documentation/CodingStyle" and the script 3856"scripts/Lindent" in your Linux kernel source directory. In sources 3857originating from U-Boot a style corresponding to "Lindent -pcs" (adding 3858spaces before parameters to function calls) is actually used. 3859 3860Source files originating from a different project (for example the 3861MTD subsystem) are generally exempt from these guidelines and are not 3862reformated to ease subsequent migration to newer versions of those 3863sources. 3864 3865Please note that U-Boot is implemented in C (and to some small parts in 3866Assembler); no C++ is used, so please do not use C++ style comments (//) 3867in your code. 3868 3869Please also stick to the following formatting rules: 3870- remove any trailing white space 3871- use TAB characters for indentation, not spaces 3872- make sure NOT to use DOS '\r\n' line feeds 3873- do not add more than 2 empty lines to source files 3874- do not add trailing empty lines to source files 3875 3876Submissions which do not conform to the standards may be returned 3877with a request to reformat the changes. 3878 3879 3880Submitting Patches: 3881------------------- 3882 3883Since the number of patches for U-Boot is growing, we need to 3884establish some rules. Submissions which do not conform to these rules 3885may be rejected, even when they contain important and valuable stuff. 3886 3887Patches shall be sent to the u-boot-users mailing list. 3888 3889Please see http://www.denx.de/wiki/UBoot/Patches for details. 3890 3891When you send a patch, please include the following information with 3892it: 3893 3894* For bug fixes: a description of the bug and how your patch fixes 3895 this bug. Please try to include a way of demonstrating that the 3896 patch actually fixes something. 3897 3898* For new features: a description of the feature and your 3899 implementation. 3900 3901* A CHANGELOG entry as plaintext (separate from the patch) 3902 3903* For major contributions, your entry to the CREDITS file 3904 3905* When you add support for a new board, don't forget to add this 3906 board to the MAKEALL script, too. 3907 3908* If your patch adds new configuration options, don't forget to 3909 document these in the README file. 3910 3911* The patch itself. If you are using git (which is *strongly* 3912 recommended) you can easily generate the patch using the 3913 "git-format-patch". If you then use "git-send-email" to send it to 3914 the U-Boot mailing list, you will avoid most of the common problems 3915 with some other mail clients. 3916 3917 If you cannot use git, use "diff -purN OLD NEW". If your version of 3918 diff does not support these options, then get the latest version of 3919 GNU diff. 3920 3921 The current directory when running this command shall be the parent 3922 directory of the U-Boot source tree (i. e. please make sure that 3923 your patch includes sufficient directory information for the 3924 affected files). 3925 3926 We prefer patches as plain text. MIME attachments are discouraged, 3927 and compressed attachments must not be used. 3928 3929* If one logical set of modifications affects or creates several 3930 files, all these changes shall be submitted in a SINGLE patch file. 3931 3932* Changesets that contain different, unrelated modifications shall be 3933 submitted as SEPARATE patches, one patch per changeset. 3934 3935 3936Notes: 3937 3938* Before sending the patch, run the MAKEALL script on your patched 3939 source tree and make sure that no errors or warnings are reported 3940 for any of the boards. 3941 3942* Keep your modifications to the necessary minimum: A patch 3943 containing several unrelated changes or arbitrary reformats will be 3944 returned with a request to re-formatting / split it. 3945 3946* If you modify existing code, make sure that your new code does not 3947 add to the memory footprint of the code ;-) Small is beautiful! 3948 When adding new features, these should compile conditionally only 3949 (using #ifdef), and the resulting code with the new feature 3950 disabled must not need more memory than the old code without your 3951 modification. 3952 3953* Remember that there is a size limit of 40 kB per message on the 3954 u-boot-users mailing list. Bigger patches will be moderated. If 3955 they are reasonable and not bigger than 100 kB, they will be 3956 acknowledged. Even bigger patches should be avoided. 3957