1# 2# (C) Copyright 2000 - 2013 3# Wolfgang Denk, DENX Software Engineering, wd@denx.de. 4# 5# SPDX-License-Identifier: GPL-2.0+ 6# 7 8Summary: 9======== 10 11This directory contains the source code for U-Boot, a boot loader for 12Embedded boards based on PowerPC, ARM, MIPS and several other 13processors, which can be installed in a boot ROM and used to 14initialize and test the hardware or to download and run application 15code. 16 17The development of U-Boot is closely related to Linux: some parts of 18the source code originate in the Linux source tree, we have some 19header files in common, and special provision has been made to 20support booting of Linux images. 21 22Some attention has been paid to make this software easily 23configurable and extendable. For instance, all monitor commands are 24implemented with the same call interface, so that it's very easy to 25add new commands. Also, instead of permanently adding rarely used 26code (for instance hardware test utilities) to the monitor, you can 27load and run it dynamically. 28 29 30Status: 31======= 32 33In general, all boards for which a configuration option exists in the 34Makefile have been tested to some extent and can be considered 35"working". In fact, many of them are used in production systems. 36 37In case of problems see the CHANGELOG and CREDITS files to find out 38who contributed the specific port. The boards.cfg file lists board 39maintainers. 40 41Note: There is no CHANGELOG file in the actual U-Boot source tree; 42it can be created dynamically from the Git log using: 43 44 make CHANGELOG 45 46 47Where to get help: 48================== 49 50In case you have questions about, problems with or contributions for 51U-Boot you should send a message to the U-Boot mailing list at 52<u-boot@lists.denx.de>. There is also an archive of previous traffic 53on the mailing list - please search the archive before asking FAQ's. 54Please see http://lists.denx.de/pipermail/u-boot and 55http://dir.gmane.org/gmane.comp.boot-loaders.u-boot 56 57 58Where to get source code: 59========================= 60 61The U-Boot source code is maintained in the git repository at 62git://www.denx.de/git/u-boot.git ; you can browse it online at 63http://www.denx.de/cgi-bin/gitweb.cgi?p=u-boot.git;a=summary 64 65The "snapshot" links on this page allow you to download tarballs of 66any version you might be interested in. Official releases are also 67available for FTP download from the ftp://ftp.denx.de/pub/u-boot/ 68directory. 69 70Pre-built (and tested) images are available from 71ftp://ftp.denx.de/pub/u-boot/images/ 72 73 74Where we come from: 75=================== 76 77- start from 8xxrom sources 78- create PPCBoot project (http://sourceforge.net/projects/ppcboot) 79- clean up code 80- make it easier to add custom boards 81- make it possible to add other [PowerPC] CPUs 82- extend functions, especially: 83 * Provide extended interface to Linux boot loader 84 * S-Record download 85 * network boot 86 * PCMCIA / CompactFlash / ATA disk / SCSI ... boot 87- create ARMBoot project (http://sourceforge.net/projects/armboot) 88- add other CPU families (starting with ARM) 89- create U-Boot project (http://sourceforge.net/projects/u-boot) 90- current project page: see http://www.denx.de/wiki/U-Boot 91 92 93Names and Spelling: 94=================== 95 96The "official" name of this project is "Das U-Boot". The spelling 97"U-Boot" shall be used in all written text (documentation, comments 98in source files etc.). Example: 99 100 This is the README file for the U-Boot project. 101 102File names etc. shall be based on the string "u-boot". Examples: 103 104 include/asm-ppc/u-boot.h 105 106 #include <asm/u-boot.h> 107 108Variable names, preprocessor constants etc. shall be either based on 109the string "u_boot" or on "U_BOOT". Example: 110 111 U_BOOT_VERSION u_boot_logo 112 IH_OS_U_BOOT u_boot_hush_start 113 114 115Versioning: 116=========== 117 118Starting with the release in October 2008, the names of the releases 119were changed from numerical release numbers without deeper meaning 120into a time stamp based numbering. Regular releases are identified by 121names consisting of the calendar year and month of the release date. 122Additional fields (if present) indicate release candidates or bug fix 123releases in "stable" maintenance trees. 124 125Examples: 126 U-Boot v2009.11 - Release November 2009 127 U-Boot v2009.11.1 - Release 1 in version November 2009 stable tree 128 U-Boot v2010.09-rc1 - Release candiate 1 for September 2010 release 129 130 131Directory Hierarchy: 132==================== 133 134/arch Architecture specific files 135 /arc Files generic to ARC architecture 136 /cpu CPU specific files 137 /arc700 Files specific to ARC 700 CPUs 138 /lib Architecture specific library files 139 /arm Files generic to ARM architecture 140 /cpu CPU specific files 141 /arm720t Files specific to ARM 720 CPUs 142 /arm920t Files specific to ARM 920 CPUs 143 /at91 Files specific to Atmel AT91RM9200 CPU 144 /imx Files specific to Freescale MC9328 i.MX CPUs 145 /s3c24x0 Files specific to Samsung S3C24X0 CPUs 146 /arm926ejs Files specific to ARM 926 CPUs 147 /arm1136 Files specific to ARM 1136 CPUs 148 /pxa Files specific to Intel XScale PXA CPUs 149 /sa1100 Files specific to Intel StrongARM SA1100 CPUs 150 /lib Architecture specific library files 151 /avr32 Files generic to AVR32 architecture 152 /cpu CPU specific files 153 /lib Architecture specific library files 154 /blackfin Files generic to Analog Devices Blackfin architecture 155 /cpu CPU specific files 156 /lib Architecture specific library files 157 /m68k Files generic to m68k architecture 158 /cpu CPU specific files 159 /mcf52x2 Files specific to Freescale ColdFire MCF52x2 CPUs 160 /mcf5227x Files specific to Freescale ColdFire MCF5227x CPUs 161 /mcf532x Files specific to Freescale ColdFire MCF5329 CPUs 162 /mcf5445x Files specific to Freescale ColdFire MCF5445x CPUs 163 /mcf547x_8x Files specific to Freescale ColdFire MCF547x_8x CPUs 164 /lib Architecture specific library files 165 /microblaze Files generic to microblaze architecture 166 /cpu CPU specific files 167 /lib Architecture specific library files 168 /mips Files generic to MIPS architecture 169 /cpu CPU specific files 170 /mips32 Files specific to MIPS32 CPUs 171 /mips64 Files specific to MIPS64 CPUs 172 /lib Architecture specific library files 173 /nds32 Files generic to NDS32 architecture 174 /cpu CPU specific files 175 /n1213 Files specific to Andes Technology N1213 CPUs 176 /lib Architecture specific library files 177 /nios2 Files generic to Altera NIOS2 architecture 178 /cpu CPU specific files 179 /lib Architecture specific library files 180 /openrisc Files generic to OpenRISC architecture 181 /cpu CPU specific files 182 /lib Architecture specific library files 183 /powerpc Files generic to PowerPC architecture 184 /cpu CPU specific files 185 /mpc5xx Files specific to Freescale MPC5xx CPUs 186 /mpc5xxx Files specific to Freescale MPC5xxx CPUs 187 /mpc8xx Files specific to Freescale MPC8xx CPUs 188 /mpc8260 Files specific to Freescale MPC8260 CPUs 189 /mpc85xx Files specific to Freescale MPC85xx CPUs 190 /ppc4xx Files specific to AMCC PowerPC 4xx CPUs 191 /lib Architecture specific library files 192 /sh Files generic to SH architecture 193 /cpu CPU specific files 194 /sh2 Files specific to sh2 CPUs 195 /sh3 Files specific to sh3 CPUs 196 /sh4 Files specific to sh4 CPUs 197 /lib Architecture specific library files 198 /sparc Files generic to SPARC architecture 199 /cpu CPU specific files 200 /leon2 Files specific to Gaisler LEON2 SPARC CPU 201 /leon3 Files specific to Gaisler LEON3 SPARC CPU 202 /lib Architecture specific library files 203 /x86 Files generic to x86 architecture 204 /cpu CPU specific files 205 /lib Architecture specific library files 206/api Machine/arch independent API for external apps 207/board Board dependent files 208/common Misc architecture independent functions 209/disk Code for disk drive partition handling 210/doc Documentation (don't expect too much) 211/drivers Commonly used device drivers 212/dts Contains Makefile for building internal U-Boot fdt. 213/examples Example code for standalone applications, etc. 214/fs Filesystem code (cramfs, ext2, jffs2, etc.) 215/include Header Files 216/lib Files generic to all architectures 217 /libfdt Library files to support flattened device trees 218 /lzma Library files to support LZMA decompression 219 /lzo Library files to support LZO decompression 220/net Networking code 221/post Power On Self Test 222/spl Secondary Program Loader framework 223/tools Tools to build S-Record or U-Boot images, etc. 224 225Software Configuration: 226======================= 227 228Configuration is usually done using C preprocessor defines; the 229rationale behind that is to avoid dead code whenever possible. 230 231There are two classes of configuration variables: 232 233* Configuration _OPTIONS_: 234 These are selectable by the user and have names beginning with 235 "CONFIG_". 236 237* Configuration _SETTINGS_: 238 These depend on the hardware etc. and should not be meddled with if 239 you don't know what you're doing; they have names beginning with 240 "CONFIG_SYS_". 241 242Later we will add a configuration tool - probably similar to or even 243identical to what's used for the Linux kernel. Right now, we have to 244do the configuration by hand, which means creating some symbolic 245links and editing some configuration files. We use the TQM8xxL boards 246as an example here. 247 248 249Selection of Processor Architecture and Board Type: 250--------------------------------------------------- 251 252For all supported boards there are ready-to-use default 253configurations available; just type "make <board_name>_defconfig". 254 255Example: For a TQM823L module type: 256 257 cd u-boot 258 make TQM823L_defconfig 259 260For the Cogent platform, you need to specify the CPU type as well; 261e.g. "make cogent_mpc8xx_defconfig". And also configure the cogent 262directory according to the instructions in cogent/README. 263 264 265Sandbox Environment: 266-------------------- 267 268U-Boot can be built natively to run on a Linux host using the 'sandbox' 269board. This allows feature development which is not board- or architecture- 270specific to be undertaken on a native platform. The sandbox is also used to 271run some of U-Boot's tests. 272 273See board/sandbox/README.sandbox for more details. 274 275 276Board Initialisation Flow: 277-------------------------- 278 279This is the intended start-up flow for boards. This should apply for both 280SPL and U-Boot proper (i.e. they both follow the same rules). At present SPL 281mostly uses a separate code path, but the funtion names and roles of each 282function are the same. Some boards or architectures may not conform to this. 283At least most ARM boards which use CONFIG_SPL_FRAMEWORK conform to this. 284 285Execution starts with start.S with three functions called during init after 286that. The purpose and limitations of each is described below. 287 288lowlevel_init(): 289 - purpose: essential init to permit execution to reach board_init_f() 290 - no global_data or BSS 291 - there is no stack (ARMv7 may have one but it will soon be removed) 292 - must not set up SDRAM or use console 293 - must only do the bare minimum to allow execution to continue to 294 board_init_f() 295 - this is almost never needed 296 - return normally from this function 297 298board_init_f(): 299 - purpose: set up the machine ready for running board_init_r(): 300 i.e. SDRAM and serial UART 301 - global_data is available 302 - stack is in SRAM 303 - BSS is not available, so you cannot use global/static variables, 304 only stack variables and global_data 305 306 Non-SPL-specific notes: 307 - dram_init() is called to set up DRAM. If already done in SPL this 308 can do nothing 309 310 SPL-specific notes: 311 - you can override the entire board_init_f() function with your own 312 version as needed. 313 - preloader_console_init() can be called here in extremis 314 - should set up SDRAM, and anything needed to make the UART work 315 - these is no need to clear BSS, it will be done by crt0.S 316 - must return normally from this function (don't call board_init_r() 317 directly) 318 319Here the BSS is cleared. For SPL, if CONFIG_SPL_STACK_R is defined, then at 320this point the stack and global_data are relocated to below 321CONFIG_SPL_STACK_R_ADDR. For non-SPL, U-Boot is relocated to run at the top of 322memory. 323 324board_init_r(): 325 - purpose: main execution, common code 326 - global_data is available 327 - SDRAM is available 328 - BSS is available, all static/global variables can be used 329 - execution eventually continues to main_loop() 330 331 Non-SPL-specific notes: 332 - U-Boot is relocated to the top of memory and is now running from 333 there. 334 335 SPL-specific notes: 336 - stack is optionally in SDRAM, if CONFIG_SPL_STACK_R is defined and 337 CONFIG_SPL_STACK_R_ADDR points into SDRAM 338 - preloader_console_init() can be called here - typically this is 339 done by defining CONFIG_SPL_BOARD_INIT and then supplying a 340 spl_board_init() function containing this call 341 - loads U-Boot or (in falcon mode) Linux 342 343 344 345Configuration Options: 346---------------------- 347 348Configuration depends on the combination of board and CPU type; all 349such information is kept in a configuration file 350"include/configs/<board_name>.h". 351 352Example: For a TQM823L module, all configuration settings are in 353"include/configs/TQM823L.h". 354 355 356Many of the options are named exactly as the corresponding Linux 357kernel configuration options. The intention is to make it easier to 358build a config tool - later. 359 360 361The following options need to be configured: 362 363- CPU Type: Define exactly one, e.g. CONFIG_MPC85XX. 364 365- Board Type: Define exactly one, e.g. CONFIG_MPC8540ADS. 366 367- CPU Daughterboard Type: (if CONFIG_ATSTK1000 is defined) 368 Define exactly one, e.g. CONFIG_ATSTK1002 369 370- CPU Module Type: (if CONFIG_COGENT is defined) 371 Define exactly one of 372 CONFIG_CMA286_60_OLD 373--- FIXME --- not tested yet: 374 CONFIG_CMA286_60, CONFIG_CMA286_21, CONFIG_CMA286_60P, 375 CONFIG_CMA287_23, CONFIG_CMA287_50 376 377- Motherboard Type: (if CONFIG_COGENT is defined) 378 Define exactly one of 379 CONFIG_CMA101, CONFIG_CMA102 380 381- Motherboard I/O Modules: (if CONFIG_COGENT is defined) 382 Define one or more of 383 CONFIG_CMA302 384 385- Motherboard Options: (if CONFIG_CMA101 or CONFIG_CMA102 are defined) 386 Define one or more of 387 CONFIG_LCD_HEARTBEAT - update a character position on 388 the LCD display every second with 389 a "rotator" |\-/|\-/ 390 391- Marvell Family Member 392 CONFIG_SYS_MVFS - define it if you want to enable 393 multiple fs option at one time 394 for marvell soc family 395 396- 8xx CPU Options: (if using an MPC8xx CPU) 397 CONFIG_8xx_GCLK_FREQ - deprecated: CPU clock if 398 get_gclk_freq() cannot work 399 e.g. if there is no 32KHz 400 reference PIT/RTC clock 401 CONFIG_8xx_OSCLK - PLL input clock (either EXTCLK 402 or XTAL/EXTAL) 403 404- 859/866/885 CPU options: (if using a MPC859 or MPC866 or MPC885 CPU): 405 CONFIG_SYS_8xx_CPUCLK_MIN 406 CONFIG_SYS_8xx_CPUCLK_MAX 407 CONFIG_8xx_CPUCLK_DEFAULT 408 See doc/README.MPC866 409 410 CONFIG_SYS_MEASURE_CPUCLK 411 412 Define this to measure the actual CPU clock instead 413 of relying on the correctness of the configured 414 values. Mostly useful for board bringup to make sure 415 the PLL is locked at the intended frequency. Note 416 that this requires a (stable) reference clock (32 kHz 417 RTC clock or CONFIG_SYS_8XX_XIN) 418 419 CONFIG_SYS_DELAYED_ICACHE 420 421 Define this option if you want to enable the 422 ICache only when Code runs from RAM. 423 424- 85xx CPU Options: 425 CONFIG_SYS_PPC64 426 427 Specifies that the core is a 64-bit PowerPC implementation (implements 428 the "64" category of the Power ISA). This is necessary for ePAPR 429 compliance, among other possible reasons. 430 431 CONFIG_SYS_FSL_TBCLK_DIV 432 433 Defines the core time base clock divider ratio compared to the 434 system clock. On most PQ3 devices this is 8, on newer QorIQ 435 devices it can be 16 or 32. The ratio varies from SoC to Soc. 436 437 CONFIG_SYS_FSL_PCIE_COMPAT 438 439 Defines the string to utilize when trying to match PCIe device 440 tree nodes for the given platform. 441 442 CONFIG_SYS_PPC_E500_DEBUG_TLB 443 444 Enables a temporary TLB entry to be used during boot to work 445 around limitations in e500v1 and e500v2 external debugger 446 support. This reduces the portions of the boot code where 447 breakpoints and single stepping do not work. The value of this 448 symbol should be set to the TLB1 entry to be used for this 449 purpose. 450 451 CONFIG_SYS_FSL_ERRATUM_A004510 452 453 Enables a workaround for erratum A004510. If set, 454 then CONFIG_SYS_FSL_ERRATUM_A004510_SVR_REV and 455 CONFIG_SYS_FSL_CORENET_SNOOPVEC_COREONLY must be set. 456 457 CONFIG_SYS_FSL_ERRATUM_A004510_SVR_REV 458 CONFIG_SYS_FSL_ERRATUM_A004510_SVR_REV2 (optional) 459 460 Defines one or two SoC revisions (low 8 bits of SVR) 461 for which the A004510 workaround should be applied. 462 463 The rest of SVR is either not relevant to the decision 464 of whether the erratum is present (e.g. p2040 versus 465 p2041) or is implied by the build target, which controls 466 whether CONFIG_SYS_FSL_ERRATUM_A004510 is set. 467 468 See Freescale App Note 4493 for more information about 469 this erratum. 470 471 CONFIG_A003399_NOR_WORKAROUND 472 Enables a workaround for IFC erratum A003399. It is only 473 required during NOR boot. 474 475 CONFIG_A008044_WORKAROUND 476 Enables a workaround for T1040/T1042 erratum A008044. It is only 477 required during NAND boot and valid for Rev 1.0 SoC revision 478 479 CONFIG_SYS_FSL_CORENET_SNOOPVEC_COREONLY 480 481 This is the value to write into CCSR offset 0x18600 482 according to the A004510 workaround. 483 484 CONFIG_SYS_FSL_DSP_DDR_ADDR 485 This value denotes start offset of DDR memory which is 486 connected exclusively to the DSP cores. 487 488 CONFIG_SYS_FSL_DSP_M2_RAM_ADDR 489 This value denotes start offset of M2 memory 490 which is directly connected to the DSP core. 491 492 CONFIG_SYS_FSL_DSP_M3_RAM_ADDR 493 This value denotes start offset of M3 memory which is directly 494 connected to the DSP core. 495 496 CONFIG_SYS_FSL_DSP_CCSRBAR_DEFAULT 497 This value denotes start offset of DSP CCSR space. 498 499 CONFIG_SYS_FSL_SINGLE_SOURCE_CLK 500 Single Source Clock is clocking mode present in some of FSL SoC's. 501 In this mode, a single differential clock is used to supply 502 clocks to the sysclock, ddrclock and usbclock. 503 504 CONFIG_SYS_CPC_REINIT_F 505 This CONFIG is defined when the CPC is configured as SRAM at the 506 time of U-boot entry and is required to be re-initialized. 507 508 CONFIG_DEEP_SLEEP 509 Indicates this SoC supports deep sleep feature. If deep sleep is 510 supported, core will start to execute uboot when wakes up. 511 512- Generic CPU options: 513 CONFIG_SYS_GENERIC_GLOBAL_DATA 514 Defines global data is initialized in generic board board_init_f(). 515 If this macro is defined, global data is created and cleared in 516 generic board board_init_f(). Without this macro, architecture/board 517 should initialize global data before calling board_init_f(). 518 519 CONFIG_SYS_BIG_ENDIAN, CONFIG_SYS_LITTLE_ENDIAN 520 521 Defines the endianess of the CPU. Implementation of those 522 values is arch specific. 523 524 CONFIG_SYS_FSL_DDR 525 Freescale DDR driver in use. This type of DDR controller is 526 found in mpc83xx, mpc85xx, mpc86xx as well as some ARM core 527 SoCs. 528 529 CONFIG_SYS_FSL_DDR_ADDR 530 Freescale DDR memory-mapped register base. 531 532 CONFIG_SYS_FSL_DDR_EMU 533 Specify emulator support for DDR. Some DDR features such as 534 deskew training are not available. 535 536 CONFIG_SYS_FSL_DDRC_GEN1 537 Freescale DDR1 controller. 538 539 CONFIG_SYS_FSL_DDRC_GEN2 540 Freescale DDR2 controller. 541 542 CONFIG_SYS_FSL_DDRC_GEN3 543 Freescale DDR3 controller. 544 545 CONFIG_SYS_FSL_DDRC_GEN4 546 Freescale DDR4 controller. 547 548 CONFIG_SYS_FSL_DDRC_ARM_GEN3 549 Freescale DDR3 controller for ARM-based SoCs. 550 551 CONFIG_SYS_FSL_DDR1 552 Board config to use DDR1. It can be enabled for SoCs with 553 Freescale DDR1 or DDR2 controllers, depending on the board 554 implemetation. 555 556 CONFIG_SYS_FSL_DDR2 557 Board config to use DDR2. It can be eanbeld for SoCs with 558 Freescale DDR2 or DDR3 controllers, depending on the board 559 implementation. 560 561 CONFIG_SYS_FSL_DDR3 562 Board config to use DDR3. It can be enabled for SoCs with 563 Freescale DDR3 or DDR3L controllers. 564 565 CONFIG_SYS_FSL_DDR3L 566 Board config to use DDR3L. It can be enabled for SoCs with 567 DDR3L controllers. 568 569 CONFIG_SYS_FSL_DDR4 570 Board config to use DDR4. It can be enabled for SoCs with 571 DDR4 controllers. 572 573 CONFIG_SYS_FSL_IFC_BE 574 Defines the IFC controller register space as Big Endian 575 576 CONFIG_SYS_FSL_IFC_LE 577 Defines the IFC controller register space as Little Endian 578 579 CONFIG_SYS_FSL_PBL_PBI 580 It enables addition of RCW (Power on reset configuration) in built image. 581 Please refer doc/README.pblimage for more details 582 583 CONFIG_SYS_FSL_PBL_RCW 584 It adds PBI(pre-boot instructions) commands in u-boot build image. 585 PBI commands can be used to configure SoC before it starts the execution. 586 Please refer doc/README.pblimage for more details 587 588 CONFIG_SPL_FSL_PBL 589 It adds a target to create boot binary having SPL binary in PBI format 590 concatenated with u-boot binary. 591 592 CONFIG_SYS_FSL_DDR_BE 593 Defines the DDR controller register space as Big Endian 594 595 CONFIG_SYS_FSL_DDR_LE 596 Defines the DDR controller register space as Little Endian 597 598 CONFIG_SYS_FSL_DDR_SDRAM_BASE_PHY 599 Physical address from the view of DDR controllers. It is the 600 same as CONFIG_SYS_DDR_SDRAM_BASE for all Power SoCs. But 601 it could be different for ARM SoCs. 602 603 CONFIG_SYS_FSL_DDR_INTLV_256B 604 DDR controller interleaving on 256-byte. This is a special 605 interleaving mode, handled by Dickens for Freescale layerscape 606 SoCs with ARM core. 607 608 CONFIG_SYS_FSL_DDR_MAIN_NUM_CTRLS 609 Number of controllers used as main memory. 610 611 CONFIG_SYS_FSL_OTHER_DDR_NUM_CTRLS 612 Number of controllers used for other than main memory. 613 614 CONFIG_SYS_FSL_SEC_BE 615 Defines the SEC controller register space as Big Endian 616 617 CONFIG_SYS_FSL_SEC_LE 618 Defines the SEC controller register space as Little Endian 619 620- Intel Monahans options: 621 CONFIG_SYS_MONAHANS_RUN_MODE_OSC_RATIO 622 623 Defines the Monahans run mode to oscillator 624 ratio. Valid values are 8, 16, 24, 31. The core 625 frequency is this value multiplied by 13 MHz. 626 627 CONFIG_SYS_MONAHANS_TURBO_RUN_MODE_RATIO 628 629 Defines the Monahans turbo mode to oscillator 630 ratio. Valid values are 1 (default if undefined) and 631 2. The core frequency as calculated above is multiplied 632 by this value. 633 634- MIPS CPU options: 635 CONFIG_SYS_INIT_SP_OFFSET 636 637 Offset relative to CONFIG_SYS_SDRAM_BASE for initial stack 638 pointer. This is needed for the temporary stack before 639 relocation. 640 641 CONFIG_SYS_MIPS_CACHE_MODE 642 643 Cache operation mode for the MIPS CPU. 644 See also arch/mips/include/asm/mipsregs.h. 645 Possible values are: 646 CONF_CM_CACHABLE_NO_WA 647 CONF_CM_CACHABLE_WA 648 CONF_CM_UNCACHED 649 CONF_CM_CACHABLE_NONCOHERENT 650 CONF_CM_CACHABLE_CE 651 CONF_CM_CACHABLE_COW 652 CONF_CM_CACHABLE_CUW 653 CONF_CM_CACHABLE_ACCELERATED 654 655 CONFIG_SYS_XWAY_EBU_BOOTCFG 656 657 Special option for Lantiq XWAY SoCs for booting from NOR flash. 658 See also arch/mips/cpu/mips32/start.S. 659 660 CONFIG_XWAY_SWAP_BYTES 661 662 Enable compilation of tools/xway-swap-bytes needed for Lantiq 663 XWAY SoCs for booting from NOR flash. The U-Boot image needs to 664 be swapped if a flash programmer is used. 665 666- ARM options: 667 CONFIG_SYS_EXCEPTION_VECTORS_HIGH 668 669 Select high exception vectors of the ARM core, e.g., do not 670 clear the V bit of the c1 register of CP15. 671 672 CONFIG_SYS_THUMB_BUILD 673 674 Use this flag to build U-Boot using the Thumb instruction 675 set for ARM architectures. Thumb instruction set provides 676 better code density. For ARM architectures that support 677 Thumb2 this flag will result in Thumb2 code generated by 678 GCC. 679 680 CONFIG_ARM_ERRATA_716044 681 CONFIG_ARM_ERRATA_742230 682 CONFIG_ARM_ERRATA_743622 683 CONFIG_ARM_ERRATA_751472 684 CONFIG_ARM_ERRATA_794072 685 CONFIG_ARM_ERRATA_761320 686 687 If set, the workarounds for these ARM errata are applied early 688 during U-Boot startup. Note that these options force the 689 workarounds to be applied; no CPU-type/version detection 690 exists, unlike the similar options in the Linux kernel. Do not 691 set these options unless they apply! 692 693 COUNTER_FREQUENCY 694 Generic timer clock source frequency. 695 696 COUNTER_FREQUENCY_REAL 697 Generic timer clock source frequency if the real clock is 698 different from COUNTER_FREQUENCY, and can only be determined 699 at run time. 700 701 NOTE: The following can be machine specific errata. These 702 do have ability to provide rudimentary version and machine 703 specific checks, but expect no product checks. 704 CONFIG_ARM_ERRATA_430973 705 CONFIG_ARM_ERRATA_454179 706 CONFIG_ARM_ERRATA_621766 707 CONFIG_ARM_ERRATA_798870 708 CONFIG_ARM_ERRATA_801819 709 710- Tegra SoC options: 711 CONFIG_TEGRA_SUPPORT_NON_SECURE 712 713 Support executing U-Boot in non-secure (NS) mode. Certain 714 impossible actions will be skipped if the CPU is in NS mode, 715 such as ARM architectural timer initialization. 716 717- Linux Kernel Interface: 718 CONFIG_CLOCKS_IN_MHZ 719 720 U-Boot stores all clock information in Hz 721 internally. For binary compatibility with older Linux 722 kernels (which expect the clocks passed in the 723 bd_info data to be in MHz) the environment variable 724 "clocks_in_mhz" can be defined so that U-Boot 725 converts clock data to MHZ before passing it to the 726 Linux kernel. 727 When CONFIG_CLOCKS_IN_MHZ is defined, a definition of 728 "clocks_in_mhz=1" is automatically included in the 729 default environment. 730 731 CONFIG_MEMSIZE_IN_BYTES [relevant for MIPS only] 732 733 When transferring memsize parameter to Linux, some versions 734 expect it to be in bytes, others in MB. 735 Define CONFIG_MEMSIZE_IN_BYTES to make it in bytes. 736 737 CONFIG_OF_LIBFDT 738 739 New kernel versions are expecting firmware settings to be 740 passed using flattened device trees (based on open firmware 741 concepts). 742 743 CONFIG_OF_LIBFDT 744 * New libfdt-based support 745 * Adds the "fdt" command 746 * The bootm command automatically updates the fdt 747 748 OF_CPU - The proper name of the cpus node (only required for 749 MPC512X and MPC5xxx based boards). 750 OF_SOC - The proper name of the soc node (only required for 751 MPC512X and MPC5xxx based boards). 752 OF_TBCLK - The timebase frequency. 753 OF_STDOUT_PATH - The path to the console device 754 755 boards with QUICC Engines require OF_QE to set UCC MAC 756 addresses 757 758 CONFIG_OF_BOARD_SETUP 759 760 Board code has addition modification that it wants to make 761 to the flat device tree before handing it off to the kernel 762 763 CONFIG_OF_SYSTEM_SETUP 764 765 Other code has addition modification that it wants to make 766 to the flat device tree before handing it off to the kernel. 767 This causes ft_system_setup() to be called before booting 768 the kernel. 769 770 CONFIG_OF_BOOT_CPU 771 772 This define fills in the correct boot CPU in the boot 773 param header, the default value is zero if undefined. 774 775 CONFIG_OF_IDE_FIXUP 776 777 U-Boot can detect if an IDE device is present or not. 778 If not, and this new config option is activated, U-Boot 779 removes the ATA node from the DTS before booting Linux, 780 so the Linux IDE driver does not probe the device and 781 crash. This is needed for buggy hardware (uc101) where 782 no pull down resistor is connected to the signal IDE5V_DD7. 783 784 CONFIG_MACH_TYPE [relevant for ARM only][mandatory] 785 786 This setting is mandatory for all boards that have only one 787 machine type and must be used to specify the machine type 788 number as it appears in the ARM machine registry 789 (see http://www.arm.linux.org.uk/developer/machines/). 790 Only boards that have multiple machine types supported 791 in a single configuration file and the machine type is 792 runtime discoverable, do not have to use this setting. 793 794- vxWorks boot parameters: 795 796 bootvx constructs a valid bootline using the following 797 environments variables: bootfile, ipaddr, serverip, hostname. 798 It loads the vxWorks image pointed bootfile. 799 800 CONFIG_SYS_VXWORKS_BOOT_DEVICE - The vxworks device name 801 CONFIG_SYS_VXWORKS_MAC_PTR - Ethernet 6 byte MA -address 802 CONFIG_SYS_VXWORKS_SERVERNAME - Name of the server 803 CONFIG_SYS_VXWORKS_BOOT_ADDR - Address of boot parameters 804 805 CONFIG_SYS_VXWORKS_ADD_PARAMS 806 807 Add it at the end of the bootline. E.g "u=username pw=secret" 808 809 Note: If a "bootargs" environment is defined, it will overwride 810 the defaults discussed just above. 811 812- Cache Configuration: 813 CONFIG_SYS_ICACHE_OFF - Do not enable instruction cache in U-Boot 814 CONFIG_SYS_DCACHE_OFF - Do not enable data cache in U-Boot 815 CONFIG_SYS_L2CACHE_OFF- Do not enable L2 cache in U-Boot 816 817- Cache Configuration for ARM: 818 CONFIG_SYS_L2_PL310 - Enable support for ARM PL310 L2 cache 819 controller 820 CONFIG_SYS_PL310_BASE - Physical base address of PL310 821 controller register space 822 823- Serial Ports: 824 CONFIG_PL010_SERIAL 825 826 Define this if you want support for Amba PrimeCell PL010 UARTs. 827 828 CONFIG_PL011_SERIAL 829 830 Define this if you want support for Amba PrimeCell PL011 UARTs. 831 832 CONFIG_PL011_CLOCK 833 834 If you have Amba PrimeCell PL011 UARTs, set this variable to 835 the clock speed of the UARTs. 836 837 CONFIG_PL01x_PORTS 838 839 If you have Amba PrimeCell PL010 or PL011 UARTs on your board, 840 define this to a list of base addresses for each (supported) 841 port. See e.g. include/configs/versatile.h 842 843 CONFIG_SERIAL_HW_FLOW_CONTROL 844 845 Define this variable to enable hw flow control in serial driver. 846 Current user of this option is drivers/serial/nsl16550.c driver 847 848- Console Interface: 849 Depending on board, define exactly one serial port 850 (like CONFIG_8xx_CONS_SMC1, CONFIG_8xx_CONS_SMC2, 851 CONFIG_8xx_CONS_SCC1, ...), or switch off the serial 852 console by defining CONFIG_8xx_CONS_NONE 853 854 Note: if CONFIG_8xx_CONS_NONE is defined, the serial 855 port routines must be defined elsewhere 856 (i.e. serial_init(), serial_getc(), ...) 857 858 CONFIG_CFB_CONSOLE 859 Enables console device for a color framebuffer. Needs following 860 defines (cf. smiLynxEM, i8042) 861 VIDEO_FB_LITTLE_ENDIAN graphic memory organisation 862 (default big endian) 863 VIDEO_HW_RECTFILL graphic chip supports 864 rectangle fill 865 (cf. smiLynxEM) 866 VIDEO_HW_BITBLT graphic chip supports 867 bit-blit (cf. smiLynxEM) 868 VIDEO_VISIBLE_COLS visible pixel columns 869 (cols=pitch) 870 VIDEO_VISIBLE_ROWS visible pixel rows 871 VIDEO_PIXEL_SIZE bytes per pixel 872 VIDEO_DATA_FORMAT graphic data format 873 (0-5, cf. cfb_console.c) 874 VIDEO_FB_ADRS framebuffer address 875 VIDEO_KBD_INIT_FCT keyboard int fct 876 (i.e. i8042_kbd_init()) 877 VIDEO_TSTC_FCT test char fct 878 (i.e. i8042_tstc) 879 VIDEO_GETC_FCT get char fct 880 (i.e. i8042_getc) 881 CONFIG_CONSOLE_CURSOR cursor drawing on/off 882 (requires blink timer 883 cf. i8042.c) 884 CONFIG_SYS_CONSOLE_BLINK_COUNT blink interval (cf. i8042.c) 885 CONFIG_CONSOLE_TIME display time/date info in 886 upper right corner 887 (requires CONFIG_CMD_DATE) 888 CONFIG_VIDEO_LOGO display Linux logo in 889 upper left corner 890 CONFIG_VIDEO_BMP_LOGO use bmp_logo.h instead of 891 linux_logo.h for logo. 892 Requires CONFIG_VIDEO_LOGO 893 CONFIG_CONSOLE_EXTRA_INFO 894 additional board info beside 895 the logo 896 897 When CONFIG_CFB_CONSOLE_ANSI is defined, console will support 898 a limited number of ANSI escape sequences (cursor control, 899 erase functions and limited graphics rendition control). 900 901 When CONFIG_CFB_CONSOLE is defined, video console is 902 default i/o. Serial console can be forced with 903 environment 'console=serial'. 904 905 When CONFIG_SILENT_CONSOLE is defined, all console 906 messages (by U-Boot and Linux!) can be silenced with 907 the "silent" environment variable. See 908 doc/README.silent for more information. 909 910 CONFIG_SYS_CONSOLE_BG_COL: define the backgroundcolor, default 911 is 0x00. 912 CONFIG_SYS_CONSOLE_FG_COL: define the foregroundcolor, default 913 is 0xa0. 914 915- Console Baudrate: 916 CONFIG_BAUDRATE - in bps 917 Select one of the baudrates listed in 918 CONFIG_SYS_BAUDRATE_TABLE, see below. 919 CONFIG_SYS_BRGCLK_PRESCALE, baudrate prescale 920 921- Console Rx buffer length 922 With CONFIG_SYS_SMC_RXBUFLEN it is possible to define 923 the maximum receive buffer length for the SMC. 924 This option is actual only for 82xx and 8xx possible. 925 If using CONFIG_SYS_SMC_RXBUFLEN also CONFIG_SYS_MAXIDLE 926 must be defined, to setup the maximum idle timeout for 927 the SMC. 928 929- Pre-Console Buffer: 930 Prior to the console being initialised (i.e. serial UART 931 initialised etc) all console output is silently discarded. 932 Defining CONFIG_PRE_CONSOLE_BUFFER will cause U-Boot to 933 buffer any console messages prior to the console being 934 initialised to a buffer of size CONFIG_PRE_CON_BUF_SZ 935 bytes located at CONFIG_PRE_CON_BUF_ADDR. The buffer is 936 a circular buffer, so if more than CONFIG_PRE_CON_BUF_SZ 937 bytes are output before the console is initialised, the 938 earlier bytes are discarded. 939 940 Note that when printing the buffer a copy is made on the 941 stack so CONFIG_PRE_CON_BUF_SZ must fit on the stack. 942 943 'Sane' compilers will generate smaller code if 944 CONFIG_PRE_CON_BUF_SZ is a power of 2 945 946- Safe printf() functions 947 Define CONFIG_SYS_VSNPRINTF to compile in safe versions of 948 the printf() functions. These are defined in 949 include/vsprintf.h and include snprintf(), vsnprintf() and 950 so on. Code size increase is approximately 300-500 bytes. 951 If this option is not given then these functions will 952 silently discard their buffer size argument - this means 953 you are not getting any overflow checking in this case. 954 955- Boot Delay: CONFIG_BOOTDELAY - in seconds 956 Delay before automatically booting the default image; 957 set to -1 to disable autoboot. 958 set to -2 to autoboot with no delay and not check for abort 959 (even when CONFIG_ZERO_BOOTDELAY_CHECK is defined). 960 961 See doc/README.autoboot for these options that 962 work with CONFIG_BOOTDELAY. None are required. 963 CONFIG_BOOT_RETRY_TIME 964 CONFIG_BOOT_RETRY_MIN 965 CONFIG_AUTOBOOT_KEYED 966 CONFIG_AUTOBOOT_PROMPT 967 CONFIG_AUTOBOOT_DELAY_STR 968 CONFIG_AUTOBOOT_STOP_STR 969 CONFIG_ZERO_BOOTDELAY_CHECK 970 CONFIG_RESET_TO_RETRY 971 972- Autoboot Command: 973 CONFIG_BOOTCOMMAND 974 Only needed when CONFIG_BOOTDELAY is enabled; 975 define a command string that is automatically executed 976 when no character is read on the console interface 977 within "Boot Delay" after reset. 978 979 CONFIG_BOOTARGS 980 This can be used to pass arguments to the bootm 981 command. The value of CONFIG_BOOTARGS goes into the 982 environment value "bootargs". 983 984 CONFIG_RAMBOOT and CONFIG_NFSBOOT 985 The value of these goes into the environment as 986 "ramboot" and "nfsboot" respectively, and can be used 987 as a convenience, when switching between booting from 988 RAM and NFS. 989 990- Bootcount: 991 CONFIG_BOOTCOUNT_LIMIT 992 Implements a mechanism for detecting a repeating reboot 993 cycle, see: 994 http://www.denx.de/wiki/view/DULG/UBootBootCountLimit 995 996 CONFIG_BOOTCOUNT_ENV 997 If no softreset save registers are found on the hardware 998 "bootcount" is stored in the environment. To prevent a 999 saveenv on all reboots, the environment variable 1000 "upgrade_available" is used. If "upgrade_available" is 1001 0, "bootcount" is always 0, if "upgrade_available" is 1002 1 "bootcount" is incremented in the environment. 1003 So the Userspace Applikation must set the "upgrade_available" 1004 and "bootcount" variable to 0, if a boot was successfully. 1005 1006- Pre-Boot Commands: 1007 CONFIG_PREBOOT 1008 1009 When this option is #defined, the existence of the 1010 environment variable "preboot" will be checked 1011 immediately before starting the CONFIG_BOOTDELAY 1012 countdown and/or running the auto-boot command resp. 1013 entering interactive mode. 1014 1015 This feature is especially useful when "preboot" is 1016 automatically generated or modified. For an example 1017 see the LWMON board specific code: here "preboot" is 1018 modified when the user holds down a certain 1019 combination of keys on the (special) keyboard when 1020 booting the systems 1021 1022- Serial Download Echo Mode: 1023 CONFIG_LOADS_ECHO 1024 If defined to 1, all characters received during a 1025 serial download (using the "loads" command) are 1026 echoed back. This might be needed by some terminal 1027 emulations (like "cu"), but may as well just take 1028 time on others. This setting #define's the initial 1029 value of the "loads_echo" environment variable. 1030 1031- Kgdb Serial Baudrate: (if CONFIG_CMD_KGDB is defined) 1032 CONFIG_KGDB_BAUDRATE 1033 Select one of the baudrates listed in 1034 CONFIG_SYS_BAUDRATE_TABLE, see below. 1035 1036- Monitor Functions: 1037 Monitor commands can be included or excluded 1038 from the build by using the #include files 1039 <config_cmd_all.h> and #undef'ing unwanted 1040 commands, or adding #define's for wanted commands. 1041 1042 The default command configuration includes all commands 1043 except those marked below with a "*". 1044 1045 CONFIG_CMD_AES AES 128 CBC encrypt/decrypt 1046 CONFIG_CMD_ASKENV * ask for env variable 1047 CONFIG_CMD_BDI bdinfo 1048 CONFIG_CMD_BEDBUG * Include BedBug Debugger 1049 CONFIG_CMD_BMP * BMP support 1050 CONFIG_CMD_BSP * Board specific commands 1051 CONFIG_CMD_BOOTD bootd 1052 CONFIG_CMD_BOOTI * ARM64 Linux kernel Image support 1053 CONFIG_CMD_CACHE * icache, dcache 1054 CONFIG_CMD_CLK * clock command support 1055 CONFIG_CMD_CONSOLE coninfo 1056 CONFIG_CMD_CRC32 * crc32 1057 CONFIG_CMD_DATE * support for RTC, date/time... 1058 CONFIG_CMD_DHCP * DHCP support 1059 CONFIG_CMD_DIAG * Diagnostics 1060 CONFIG_CMD_DS4510 * ds4510 I2C gpio commands 1061 CONFIG_CMD_DS4510_INFO * ds4510 I2C info command 1062 CONFIG_CMD_DS4510_MEM * ds4510 I2C eeprom/sram commansd 1063 CONFIG_CMD_DS4510_RST * ds4510 I2C rst command 1064 CONFIG_CMD_DTT * Digital Therm and Thermostat 1065 CONFIG_CMD_ECHO echo arguments 1066 CONFIG_CMD_EDITENV edit env variable 1067 CONFIG_CMD_EEPROM * EEPROM read/write support 1068 CONFIG_CMD_ELF * bootelf, bootvx 1069 CONFIG_CMD_ENV_CALLBACK * display details about env callbacks 1070 CONFIG_CMD_ENV_FLAGS * display details about env flags 1071 CONFIG_CMD_ENV_EXISTS * check existence of env variable 1072 CONFIG_CMD_EXPORTENV * export the environment 1073 CONFIG_CMD_EXT2 * ext2 command support 1074 CONFIG_CMD_EXT4 * ext4 command support 1075 CONFIG_CMD_FS_GENERIC * filesystem commands (e.g. load, ls) 1076 that work for multiple fs types 1077 CONFIG_CMD_FS_UUID * Look up a filesystem UUID 1078 CONFIG_CMD_SAVEENV saveenv 1079 CONFIG_CMD_FDC * Floppy Disk Support 1080 CONFIG_CMD_FAT * FAT command support 1081 CONFIG_CMD_FLASH flinfo, erase, protect 1082 CONFIG_CMD_FPGA FPGA device initialization support 1083 CONFIG_CMD_FUSE * Device fuse support 1084 CONFIG_CMD_GETTIME * Get time since boot 1085 CONFIG_CMD_GO * the 'go' command (exec code) 1086 CONFIG_CMD_GREPENV * search environment 1087 CONFIG_CMD_HASH * calculate hash / digest 1088 CONFIG_CMD_HWFLOW * RTS/CTS hw flow control 1089 CONFIG_CMD_I2C * I2C serial bus support 1090 CONFIG_CMD_IDE * IDE harddisk support 1091 CONFIG_CMD_IMI iminfo 1092 CONFIG_CMD_IMLS List all images found in NOR flash 1093 CONFIG_CMD_IMLS_NAND * List all images found in NAND flash 1094 CONFIG_CMD_IMMAP * IMMR dump support 1095 CONFIG_CMD_IOTRACE * I/O tracing for debugging 1096 CONFIG_CMD_IMPORTENV * import an environment 1097 CONFIG_CMD_INI * import data from an ini file into the env 1098 CONFIG_CMD_IRQ * irqinfo 1099 CONFIG_CMD_ITEST Integer/string test of 2 values 1100 CONFIG_CMD_JFFS2 * JFFS2 Support 1101 CONFIG_CMD_KGDB * kgdb 1102 CONFIG_CMD_LDRINFO * ldrinfo (display Blackfin loader) 1103 CONFIG_CMD_LINK_LOCAL * link-local IP address auto-configuration 1104 (169.254.*.*) 1105 CONFIG_CMD_LOADB loadb 1106 CONFIG_CMD_LOADS loads 1107 CONFIG_CMD_MD5SUM * print md5 message digest 1108 (requires CONFIG_CMD_MEMORY and CONFIG_MD5) 1109 CONFIG_CMD_MEMINFO * Display detailed memory information 1110 CONFIG_CMD_MEMORY md, mm, nm, mw, cp, cmp, crc, base, 1111 loop, loopw 1112 CONFIG_CMD_MEMTEST * mtest 1113 CONFIG_CMD_MISC Misc functions like sleep etc 1114 CONFIG_CMD_MMC * MMC memory mapped support 1115 CONFIG_CMD_MII * MII utility commands 1116 CONFIG_CMD_MTDPARTS * MTD partition support 1117 CONFIG_CMD_NAND * NAND support 1118 CONFIG_CMD_NET bootp, tftpboot, rarpboot 1119 CONFIG_CMD_NFS NFS support 1120 CONFIG_CMD_PCA953X * PCA953x I2C gpio commands 1121 CONFIG_CMD_PCA953X_INFO * PCA953x I2C gpio info command 1122 CONFIG_CMD_PCI * pciinfo 1123 CONFIG_CMD_PCMCIA * PCMCIA support 1124 CONFIG_CMD_PING * send ICMP ECHO_REQUEST to network 1125 host 1126 CONFIG_CMD_PORTIO * Port I/O 1127 CONFIG_CMD_READ * Read raw data from partition 1128 CONFIG_CMD_REGINFO * Register dump 1129 CONFIG_CMD_RUN run command in env variable 1130 CONFIG_CMD_SANDBOX * sb command to access sandbox features 1131 CONFIG_CMD_SAVES * save S record dump 1132 CONFIG_CMD_SCSI * SCSI Support 1133 CONFIG_CMD_SDRAM * print SDRAM configuration information 1134 (requires CONFIG_CMD_I2C) 1135 CONFIG_CMD_SETGETDCR Support for DCR Register access 1136 (4xx only) 1137 CONFIG_CMD_SF * Read/write/erase SPI NOR flash 1138 CONFIG_CMD_SHA1SUM * print sha1 memory digest 1139 (requires CONFIG_CMD_MEMORY) 1140 CONFIG_CMD_SOFTSWITCH * Soft switch setting command for BF60x 1141 CONFIG_CMD_SOURCE "source" command Support 1142 CONFIG_CMD_SPI * SPI serial bus support 1143 CONFIG_CMD_TFTPSRV * TFTP transfer in server mode 1144 CONFIG_CMD_TFTPPUT * TFTP put command (upload) 1145 CONFIG_CMD_TIME * run command and report execution time (ARM specific) 1146 CONFIG_CMD_TIMER * access to the system tick timer 1147 CONFIG_CMD_USB * USB support 1148 CONFIG_CMD_CDP * Cisco Discover Protocol support 1149 CONFIG_CMD_MFSL * Microblaze FSL support 1150 CONFIG_CMD_XIMG Load part of Multi Image 1151 CONFIG_CMD_UUID * Generate random UUID or GUID string 1152 1153 EXAMPLE: If you want all functions except of network 1154 support you can write: 1155 1156 #include "config_cmd_all.h" 1157 #undef CONFIG_CMD_NET 1158 1159 Other Commands: 1160 fdt (flattened device tree) command: CONFIG_OF_LIBFDT 1161 1162 Note: Don't enable the "icache" and "dcache" commands 1163 (configuration option CONFIG_CMD_CACHE) unless you know 1164 what you (and your U-Boot users) are doing. Data 1165 cache cannot be enabled on systems like the 8xx or 1166 8260 (where accesses to the IMMR region must be 1167 uncached), and it cannot be disabled on all other 1168 systems where we (mis-) use the data cache to hold an 1169 initial stack and some data. 1170 1171 1172 XXX - this list needs to get updated! 1173 1174- Regular expression support: 1175 CONFIG_REGEX 1176 If this variable is defined, U-Boot is linked against 1177 the SLRE (Super Light Regular Expression) library, 1178 which adds regex support to some commands, as for 1179 example "env grep" and "setexpr". 1180 1181- Device tree: 1182 CONFIG_OF_CONTROL 1183 If this variable is defined, U-Boot will use a device tree 1184 to configure its devices, instead of relying on statically 1185 compiled #defines in the board file. This option is 1186 experimental and only available on a few boards. The device 1187 tree is available in the global data as gd->fdt_blob. 1188 1189 U-Boot needs to get its device tree from somewhere. This can 1190 be done using one of the two options below: 1191 1192 CONFIG_OF_EMBED 1193 If this variable is defined, U-Boot will embed a device tree 1194 binary in its image. This device tree file should be in the 1195 board directory and called <soc>-<board>.dts. The binary file 1196 is then picked up in board_init_f() and made available through 1197 the global data structure as gd->blob. 1198 1199 CONFIG_OF_SEPARATE 1200 If this variable is defined, U-Boot will build a device tree 1201 binary. It will be called u-boot.dtb. Architecture-specific 1202 code will locate it at run-time. Generally this works by: 1203 1204 cat u-boot.bin u-boot.dtb >image.bin 1205 1206 and in fact, U-Boot does this for you, creating a file called 1207 u-boot-dtb.bin which is useful in the common case. You can 1208 still use the individual files if you need something more 1209 exotic. 1210 1211- Watchdog: 1212 CONFIG_WATCHDOG 1213 If this variable is defined, it enables watchdog 1214 support for the SoC. There must be support in the SoC 1215 specific code for a watchdog. For the 8xx and 8260 1216 CPUs, the SIU Watchdog feature is enabled in the SYPCR 1217 register. When supported for a specific SoC is 1218 available, then no further board specific code should 1219 be needed to use it. 1220 1221 CONFIG_HW_WATCHDOG 1222 When using a watchdog circuitry external to the used 1223 SoC, then define this variable and provide board 1224 specific code for the "hw_watchdog_reset" function. 1225 1226 CONFIG_AT91_HW_WDT_TIMEOUT 1227 specify the timeout in seconds. default 2 seconds. 1228 1229- U-Boot Version: 1230 CONFIG_VERSION_VARIABLE 1231 If this variable is defined, an environment variable 1232 named "ver" is created by U-Boot showing the U-Boot 1233 version as printed by the "version" command. 1234 Any change to this variable will be reverted at the 1235 next reset. 1236 1237- Real-Time Clock: 1238 1239 When CONFIG_CMD_DATE is selected, the type of the RTC 1240 has to be selected, too. Define exactly one of the 1241 following options: 1242 1243 CONFIG_RTC_MPC8xx - use internal RTC of MPC8xx 1244 CONFIG_RTC_PCF8563 - use Philips PCF8563 RTC 1245 CONFIG_RTC_MC13XXX - use MC13783 or MC13892 RTC 1246 CONFIG_RTC_MC146818 - use MC146818 RTC 1247 CONFIG_RTC_DS1307 - use Maxim, Inc. DS1307 RTC 1248 CONFIG_RTC_DS1337 - use Maxim, Inc. DS1337 RTC 1249 CONFIG_RTC_DS1338 - use Maxim, Inc. DS1338 RTC 1250 CONFIG_RTC_DS1339 - use Maxim, Inc. DS1339 RTC 1251 CONFIG_RTC_DS164x - use Dallas DS164x RTC 1252 CONFIG_RTC_ISL1208 - use Intersil ISL1208 RTC 1253 CONFIG_RTC_MAX6900 - use Maxim, Inc. MAX6900 RTC 1254 CONFIG_SYS_RTC_DS1337_NOOSC - Turn off the OSC output for DS1337 1255 CONFIG_SYS_RV3029_TCR - enable trickle charger on 1256 RV3029 RTC. 1257 1258 Note that if the RTC uses I2C, then the I2C interface 1259 must also be configured. See I2C Support, below. 1260 1261- GPIO Support: 1262 CONFIG_PCA953X - use NXP's PCA953X series I2C GPIO 1263 1264 The CONFIG_SYS_I2C_PCA953X_WIDTH option specifies a list of 1265 chip-ngpio pairs that tell the PCA953X driver the number of 1266 pins supported by a particular chip. 1267 1268 Note that if the GPIO device uses I2C, then the I2C interface 1269 must also be configured. See I2C Support, below. 1270 1271- I/O tracing: 1272 When CONFIG_IO_TRACE is selected, U-Boot intercepts all I/O 1273 accesses and can checksum them or write a list of them out 1274 to memory. See the 'iotrace' command for details. This is 1275 useful for testing device drivers since it can confirm that 1276 the driver behaves the same way before and after a code 1277 change. Currently this is supported on sandbox and arm. To 1278 add support for your architecture, add '#include <iotrace.h>' 1279 to the bottom of arch/<arch>/include/asm/io.h and test. 1280 1281 Example output from the 'iotrace stats' command is below. 1282 Note that if the trace buffer is exhausted, the checksum will 1283 still continue to operate. 1284 1285 iotrace is enabled 1286 Start: 10000000 (buffer start address) 1287 Size: 00010000 (buffer size) 1288 Offset: 00000120 (current buffer offset) 1289 Output: 10000120 (start + offset) 1290 Count: 00000018 (number of trace records) 1291 CRC32: 9526fb66 (CRC32 of all trace records) 1292 1293- Timestamp Support: 1294 1295 When CONFIG_TIMESTAMP is selected, the timestamp 1296 (date and time) of an image is printed by image 1297 commands like bootm or iminfo. This option is 1298 automatically enabled when you select CONFIG_CMD_DATE . 1299 1300- Partition Labels (disklabels) Supported: 1301 Zero or more of the following: 1302 CONFIG_MAC_PARTITION Apple's MacOS partition table. 1303 CONFIG_DOS_PARTITION MS Dos partition table, traditional on the 1304 Intel architecture, USB sticks, etc. 1305 CONFIG_ISO_PARTITION ISO partition table, used on CDROM etc. 1306 CONFIG_EFI_PARTITION GPT partition table, common when EFI is the 1307 bootloader. Note 2TB partition limit; see 1308 disk/part_efi.c 1309 CONFIG_MTD_PARTITIONS Memory Technology Device partition table. 1310 1311 If IDE or SCSI support is enabled (CONFIG_CMD_IDE or 1312 CONFIG_CMD_SCSI) you must configure support for at 1313 least one non-MTD partition type as well. 1314 1315- IDE Reset method: 1316 CONFIG_IDE_RESET_ROUTINE - this is defined in several 1317 board configurations files but used nowhere! 1318 1319 CONFIG_IDE_RESET - is this is defined, IDE Reset will 1320 be performed by calling the function 1321 ide_set_reset(int reset) 1322 which has to be defined in a board specific file 1323 1324- ATAPI Support: 1325 CONFIG_ATAPI 1326 1327 Set this to enable ATAPI support. 1328 1329- LBA48 Support 1330 CONFIG_LBA48 1331 1332 Set this to enable support for disks larger than 137GB 1333 Also look at CONFIG_SYS_64BIT_LBA. 1334 Whithout these , LBA48 support uses 32bit variables and will 'only' 1335 support disks up to 2.1TB. 1336 1337 CONFIG_SYS_64BIT_LBA: 1338 When enabled, makes the IDE subsystem use 64bit sector addresses. 1339 Default is 32bit. 1340 1341- SCSI Support: 1342 At the moment only there is only support for the 1343 SYM53C8XX SCSI controller; define 1344 CONFIG_SCSI_SYM53C8XX to enable it. 1345 1346 CONFIG_SYS_SCSI_MAX_LUN [8], CONFIG_SYS_SCSI_MAX_SCSI_ID [7] and 1347 CONFIG_SYS_SCSI_MAX_DEVICE [CONFIG_SYS_SCSI_MAX_SCSI_ID * 1348 CONFIG_SYS_SCSI_MAX_LUN] can be adjusted to define the 1349 maximum numbers of LUNs, SCSI ID's and target 1350 devices. 1351 CONFIG_SYS_SCSI_SYM53C8XX_CCF to fix clock timing (80Mhz) 1352 1353 The environment variable 'scsidevs' is set to the number of 1354 SCSI devices found during the last scan. 1355 1356- NETWORK Support (PCI): 1357 CONFIG_E1000 1358 Support for Intel 8254x/8257x gigabit chips. 1359 1360 CONFIG_E1000_SPI 1361 Utility code for direct access to the SPI bus on Intel 8257x. 1362 This does not do anything useful unless you set at least one 1363 of CONFIG_CMD_E1000 or CONFIG_E1000_SPI_GENERIC. 1364 1365 CONFIG_E1000_SPI_GENERIC 1366 Allow generic access to the SPI bus on the Intel 8257x, for 1367 example with the "sspi" command. 1368 1369 CONFIG_CMD_E1000 1370 Management command for E1000 devices. When used on devices 1371 with SPI support you can reprogram the EEPROM from U-Boot. 1372 1373 CONFIG_EEPRO100 1374 Support for Intel 82557/82559/82559ER chips. 1375 Optional CONFIG_EEPRO100_SROM_WRITE enables EEPROM 1376 write routine for first time initialisation. 1377 1378 CONFIG_TULIP 1379 Support for Digital 2114x chips. 1380 Optional CONFIG_TULIP_SELECT_MEDIA for board specific 1381 modem chip initialisation (KS8761/QS6611). 1382 1383 CONFIG_NATSEMI 1384 Support for National dp83815 chips. 1385 1386 CONFIG_NS8382X 1387 Support for National dp8382[01] gigabit chips. 1388 1389- NETWORK Support (other): 1390 1391 CONFIG_DRIVER_AT91EMAC 1392 Support for AT91RM9200 EMAC. 1393 1394 CONFIG_RMII 1395 Define this to use reduced MII inteface 1396 1397 CONFIG_DRIVER_AT91EMAC_QUIET 1398 If this defined, the driver is quiet. 1399 The driver doen't show link status messages. 1400 1401 CONFIG_CALXEDA_XGMAC 1402 Support for the Calxeda XGMAC device 1403 1404 CONFIG_LAN91C96 1405 Support for SMSC's LAN91C96 chips. 1406 1407 CONFIG_LAN91C96_BASE 1408 Define this to hold the physical address 1409 of the LAN91C96's I/O space 1410 1411 CONFIG_LAN91C96_USE_32_BIT 1412 Define this to enable 32 bit addressing 1413 1414 CONFIG_SMC91111 1415 Support for SMSC's LAN91C111 chip 1416 1417 CONFIG_SMC91111_BASE 1418 Define this to hold the physical address 1419 of the device (I/O space) 1420 1421 CONFIG_SMC_USE_32_BIT 1422 Define this if data bus is 32 bits 1423 1424 CONFIG_SMC_USE_IOFUNCS 1425 Define this to use i/o functions instead of macros 1426 (some hardware wont work with macros) 1427 1428 CONFIG_DRIVER_TI_EMAC 1429 Support for davinci emac 1430 1431 CONFIG_SYS_DAVINCI_EMAC_PHY_COUNT 1432 Define this if you have more then 3 PHYs. 1433 1434 CONFIG_FTGMAC100 1435 Support for Faraday's FTGMAC100 Gigabit SoC Ethernet 1436 1437 CONFIG_FTGMAC100_EGIGA 1438 Define this to use GE link update with gigabit PHY. 1439 Define this if FTGMAC100 is connected to gigabit PHY. 1440 If your system has 10/100 PHY only, it might not occur 1441 wrong behavior. Because PHY usually return timeout or 1442 useless data when polling gigabit status and gigabit 1443 control registers. This behavior won't affect the 1444 correctnessof 10/100 link speed update. 1445 1446 CONFIG_SMC911X 1447 Support for SMSC's LAN911x and LAN921x chips 1448 1449 CONFIG_SMC911X_BASE 1450 Define this to hold the physical address 1451 of the device (I/O space) 1452 1453 CONFIG_SMC911X_32_BIT 1454 Define this if data bus is 32 bits 1455 1456 CONFIG_SMC911X_16_BIT 1457 Define this if data bus is 16 bits. If your processor 1458 automatically converts one 32 bit word to two 16 bit 1459 words you may also try CONFIG_SMC911X_32_BIT. 1460 1461 CONFIG_SH_ETHER 1462 Support for Renesas on-chip Ethernet controller 1463 1464 CONFIG_SH_ETHER_USE_PORT 1465 Define the number of ports to be used 1466 1467 CONFIG_SH_ETHER_PHY_ADDR 1468 Define the ETH PHY's address 1469 1470 CONFIG_SH_ETHER_CACHE_WRITEBACK 1471 If this option is set, the driver enables cache flush. 1472 1473- PWM Support: 1474 CONFIG_PWM_IMX 1475 Support for PWM modul on the imx6. 1476 1477- TPM Support: 1478 CONFIG_TPM 1479 Support TPM devices. 1480 1481 CONFIG_TPM_TIS_I2C 1482 Support for i2c bus TPM devices. Only one device 1483 per system is supported at this time. 1484 1485 CONFIG_TPM_TIS_I2C_BURST_LIMITATION 1486 Define the burst count bytes upper limit 1487 1488 CONFIG_TPM_ATMEL_TWI 1489 Support for Atmel TWI TPM device. Requires I2C support. 1490 1491 CONFIG_TPM_TIS_LPC 1492 Support for generic parallel port TPM devices. Only one device 1493 per system is supported at this time. 1494 1495 CONFIG_TPM_TIS_BASE_ADDRESS 1496 Base address where the generic TPM device is mapped 1497 to. Contemporary x86 systems usually map it at 1498 0xfed40000. 1499 1500 CONFIG_CMD_TPM 1501 Add tpm monitor functions. 1502 Requires CONFIG_TPM. If CONFIG_TPM_AUTH_SESSIONS is set, also 1503 provides monitor access to authorized functions. 1504 1505 CONFIG_TPM 1506 Define this to enable the TPM support library which provides 1507 functional interfaces to some TPM commands. 1508 Requires support for a TPM device. 1509 1510 CONFIG_TPM_AUTH_SESSIONS 1511 Define this to enable authorized functions in the TPM library. 1512 Requires CONFIG_TPM and CONFIG_SHA1. 1513 1514- USB Support: 1515 At the moment only the UHCI host controller is 1516 supported (PIP405, MIP405, MPC5200); define 1517 CONFIG_USB_UHCI to enable it. 1518 define CONFIG_USB_KEYBOARD to enable the USB Keyboard 1519 and define CONFIG_USB_STORAGE to enable the USB 1520 storage devices. 1521 Note: 1522 Supported are USB Keyboards and USB Floppy drives 1523 (TEAC FD-05PUB). 1524 MPC5200 USB requires additional defines: 1525 CONFIG_USB_CLOCK 1526 for 528 MHz Clock: 0x0001bbbb 1527 CONFIG_PSC3_USB 1528 for USB on PSC3 1529 CONFIG_USB_CONFIG 1530 for differential drivers: 0x00001000 1531 for single ended drivers: 0x00005000 1532 for differential drivers on PSC3: 0x00000100 1533 for single ended drivers on PSC3: 0x00004100 1534 CONFIG_SYS_USB_EVENT_POLL 1535 May be defined to allow interrupt polling 1536 instead of using asynchronous interrupts 1537 1538 CONFIG_USB_EHCI_TXFIFO_THRESH enables setting of the 1539 txfilltuning field in the EHCI controller on reset. 1540 1541 CONFIG_USB_DWC2_REG_ADDR the physical CPU address of the DWC2 1542 HW module registers. 1543 1544- USB Device: 1545 Define the below if you wish to use the USB console. 1546 Once firmware is rebuilt from a serial console issue the 1547 command "setenv stdin usbtty; setenv stdout usbtty" and 1548 attach your USB cable. The Unix command "dmesg" should print 1549 it has found a new device. The environment variable usbtty 1550 can be set to gserial or cdc_acm to enable your device to 1551 appear to a USB host as a Linux gserial device or a 1552 Common Device Class Abstract Control Model serial device. 1553 If you select usbtty = gserial you should be able to enumerate 1554 a Linux host by 1555 # modprobe usbserial vendor=0xVendorID product=0xProductID 1556 else if using cdc_acm, simply setting the environment 1557 variable usbtty to be cdc_acm should suffice. The following 1558 might be defined in YourBoardName.h 1559 1560 CONFIG_USB_DEVICE 1561 Define this to build a UDC device 1562 1563 CONFIG_USB_TTY 1564 Define this to have a tty type of device available to 1565 talk to the UDC device 1566 1567 CONFIG_USBD_HS 1568 Define this to enable the high speed support for usb 1569 device and usbtty. If this feature is enabled, a routine 1570 int is_usbd_high_speed(void) 1571 also needs to be defined by the driver to dynamically poll 1572 whether the enumeration has succeded at high speed or full 1573 speed. 1574 1575 CONFIG_SYS_CONSOLE_IS_IN_ENV 1576 Define this if you want stdin, stdout &/or stderr to 1577 be set to usbtty. 1578 1579 mpc8xx: 1580 CONFIG_SYS_USB_EXTC_CLK 0xBLAH 1581 Derive USB clock from external clock "blah" 1582 - CONFIG_SYS_USB_EXTC_CLK 0x02 1583 1584 CONFIG_SYS_USB_BRG_CLK 0xBLAH 1585 Derive USB clock from brgclk 1586 - CONFIG_SYS_USB_BRG_CLK 0x04 1587 1588 If you have a USB-IF assigned VendorID then you may wish to 1589 define your own vendor specific values either in BoardName.h 1590 or directly in usbd_vendor_info.h. If you don't define 1591 CONFIG_USBD_MANUFACTURER, CONFIG_USBD_PRODUCT_NAME, 1592 CONFIG_USBD_VENDORID and CONFIG_USBD_PRODUCTID, then U-Boot 1593 should pretend to be a Linux device to it's target host. 1594 1595 CONFIG_USBD_MANUFACTURER 1596 Define this string as the name of your company for 1597 - CONFIG_USBD_MANUFACTURER "my company" 1598 1599 CONFIG_USBD_PRODUCT_NAME 1600 Define this string as the name of your product 1601 - CONFIG_USBD_PRODUCT_NAME "acme usb device" 1602 1603 CONFIG_USBD_VENDORID 1604 Define this as your assigned Vendor ID from the USB 1605 Implementors Forum. This *must* be a genuine Vendor ID 1606 to avoid polluting the USB namespace. 1607 - CONFIG_USBD_VENDORID 0xFFFF 1608 1609 CONFIG_USBD_PRODUCTID 1610 Define this as the unique Product ID 1611 for your device 1612 - CONFIG_USBD_PRODUCTID 0xFFFF 1613 1614- ULPI Layer Support: 1615 The ULPI (UTMI Low Pin (count) Interface) PHYs are supported via 1616 the generic ULPI layer. The generic layer accesses the ULPI PHY 1617 via the platform viewport, so you need both the genric layer and 1618 the viewport enabled. Currently only Chipidea/ARC based 1619 viewport is supported. 1620 To enable the ULPI layer support, define CONFIG_USB_ULPI and 1621 CONFIG_USB_ULPI_VIEWPORT in your board configuration file. 1622 If your ULPI phy needs a different reference clock than the 1623 standard 24 MHz then you have to define CONFIG_ULPI_REF_CLK to 1624 the appropriate value in Hz. 1625 1626- MMC Support: 1627 The MMC controller on the Intel PXA is supported. To 1628 enable this define CONFIG_MMC. The MMC can be 1629 accessed from the boot prompt by mapping the device 1630 to physical memory similar to flash. Command line is 1631 enabled with CONFIG_CMD_MMC. The MMC driver also works with 1632 the FAT fs. This is enabled with CONFIG_CMD_FAT. 1633 1634 CONFIG_SH_MMCIF 1635 Support for Renesas on-chip MMCIF controller 1636 1637 CONFIG_SH_MMCIF_ADDR 1638 Define the base address of MMCIF registers 1639 1640 CONFIG_SH_MMCIF_CLK 1641 Define the clock frequency for MMCIF 1642 1643 CONFIG_GENERIC_MMC 1644 Enable the generic MMC driver 1645 1646 CONFIG_SUPPORT_EMMC_BOOT 1647 Enable some additional features of the eMMC boot partitions. 1648 1649 CONFIG_SUPPORT_EMMC_RPMB 1650 Enable the commands for reading, writing and programming the 1651 key for the Replay Protection Memory Block partition in eMMC. 1652 1653- USB Device Firmware Update (DFU) class support: 1654 CONFIG_USB_FUNCTION_DFU 1655 This enables the USB portion of the DFU USB class 1656 1657 CONFIG_CMD_DFU 1658 This enables the command "dfu" which is used to have 1659 U-Boot create a DFU class device via USB. This command 1660 requires that the "dfu_alt_info" environment variable be 1661 set and define the alt settings to expose to the host. 1662 1663 CONFIG_DFU_MMC 1664 This enables support for exposing (e)MMC devices via DFU. 1665 1666 CONFIG_DFU_NAND 1667 This enables support for exposing NAND devices via DFU. 1668 1669 CONFIG_DFU_RAM 1670 This enables support for exposing RAM via DFU. 1671 Note: DFU spec refer to non-volatile memory usage, but 1672 allow usages beyond the scope of spec - here RAM usage, 1673 one that would help mostly the developer. 1674 1675 CONFIG_SYS_DFU_DATA_BUF_SIZE 1676 Dfu transfer uses a buffer before writing data to the 1677 raw storage device. Make the size (in bytes) of this buffer 1678 configurable. The size of this buffer is also configurable 1679 through the "dfu_bufsiz" environment variable. 1680 1681 CONFIG_SYS_DFU_MAX_FILE_SIZE 1682 When updating files rather than the raw storage device, 1683 we use a static buffer to copy the file into and then write 1684 the buffer once we've been given the whole file. Define 1685 this to the maximum filesize (in bytes) for the buffer. 1686 Default is 4 MiB if undefined. 1687 1688 DFU_DEFAULT_POLL_TIMEOUT 1689 Poll timeout [ms], is the timeout a device can send to the 1690 host. The host must wait for this timeout before sending 1691 a subsequent DFU_GET_STATUS request to the device. 1692 1693 DFU_MANIFEST_POLL_TIMEOUT 1694 Poll timeout [ms], which the device sends to the host when 1695 entering dfuMANIFEST state. Host waits this timeout, before 1696 sending again an USB request to the device. 1697 1698- USB Device Android Fastboot support: 1699 CONFIG_USB_FUNCTION_FASTBOOT 1700 This enables the USB part of the fastboot gadget 1701 1702 CONFIG_CMD_FASTBOOT 1703 This enables the command "fastboot" which enables the Android 1704 fastboot mode for the platform's USB device. Fastboot is a USB 1705 protocol for downloading images, flashing and device control 1706 used on Android devices. 1707 See doc/README.android-fastboot for more information. 1708 1709 CONFIG_ANDROID_BOOT_IMAGE 1710 This enables support for booting images which use the Android 1711 image format header. 1712 1713 CONFIG_FASTBOOT_BUF_ADDR 1714 The fastboot protocol requires a large memory buffer for 1715 downloads. Define this to the starting RAM address to use for 1716 downloaded images. 1717 1718 CONFIG_FASTBOOT_BUF_SIZE 1719 The fastboot protocol requires a large memory buffer for 1720 downloads. This buffer should be as large as possible for a 1721 platform. Define this to the size available RAM for fastboot. 1722 1723 CONFIG_FASTBOOT_FLASH 1724 The fastboot protocol includes a "flash" command for writing 1725 the downloaded image to a non-volatile storage device. Define 1726 this to enable the "fastboot flash" command. 1727 1728 CONFIG_FASTBOOT_FLASH_MMC_DEV 1729 The fastboot "flash" command requires additional information 1730 regarding the non-volatile storage device. Define this to 1731 the eMMC device that fastboot should use to store the image. 1732 1733 CONFIG_FASTBOOT_GPT_NAME 1734 The fastboot "flash" command supports writing the downloaded 1735 image to the Protective MBR and the Primary GUID Partition 1736 Table. (Additionally, this downloaded image is post-processed 1737 to generate and write the Backup GUID Partition Table.) 1738 This occurs when the specified "partition name" on the 1739 "fastboot flash" command line matches this value. 1740 Default is GPT_ENTRY_NAME (currently "gpt") if undefined. 1741 1742- Journaling Flash filesystem support: 1743 CONFIG_JFFS2_NAND, CONFIG_JFFS2_NAND_OFF, CONFIG_JFFS2_NAND_SIZE, 1744 CONFIG_JFFS2_NAND_DEV 1745 Define these for a default partition on a NAND device 1746 1747 CONFIG_SYS_JFFS2_FIRST_SECTOR, 1748 CONFIG_SYS_JFFS2_FIRST_BANK, CONFIG_SYS_JFFS2_NUM_BANKS 1749 Define these for a default partition on a NOR device 1750 1751 CONFIG_SYS_JFFS_CUSTOM_PART 1752 Define this to create an own partition. You have to provide a 1753 function struct part_info* jffs2_part_info(int part_num) 1754 1755 If you define only one JFFS2 partition you may also want to 1756 #define CONFIG_SYS_JFFS_SINGLE_PART 1 1757 to disable the command chpart. This is the default when you 1758 have not defined a custom partition 1759 1760- FAT(File Allocation Table) filesystem write function support: 1761 CONFIG_FAT_WRITE 1762 1763 Define this to enable support for saving memory data as a 1764 file in FAT formatted partition. 1765 1766 This will also enable the command "fatwrite" enabling the 1767 user to write files to FAT. 1768 1769CBFS (Coreboot Filesystem) support 1770 CONFIG_CMD_CBFS 1771 1772 Define this to enable support for reading from a Coreboot 1773 filesystem. Available commands are cbfsinit, cbfsinfo, cbfsls 1774 and cbfsload. 1775 1776- FAT(File Allocation Table) filesystem cluster size: 1777 CONFIG_FS_FAT_MAX_CLUSTSIZE 1778 1779 Define the max cluster size for fat operations else 1780 a default value of 65536 will be defined. 1781 1782- Keyboard Support: 1783 CONFIG_ISA_KEYBOARD 1784 1785 Define this to enable standard (PC-Style) keyboard 1786 support 1787 1788 CONFIG_I8042_KBD 1789 Standard PC keyboard driver with US (is default) and 1790 GERMAN key layout (switch via environment 'keymap=de') support. 1791 Export function i8042_kbd_init, i8042_tstc and i8042_getc 1792 for cfb_console. Supports cursor blinking. 1793 1794 CONFIG_CROS_EC_KEYB 1795 Enables a Chrome OS keyboard using the CROS_EC interface. 1796 This uses CROS_EC to communicate with a second microcontroller 1797 which provides key scans on request. 1798 1799- Video support: 1800 CONFIG_VIDEO 1801 1802 Define this to enable video support (for output to 1803 video). 1804 1805 CONFIG_VIDEO_CT69000 1806 1807 Enable Chips & Technologies 69000 Video chip 1808 1809 CONFIG_VIDEO_SMI_LYNXEM 1810 Enable Silicon Motion SMI 712/710/810 Video chip. The 1811 video output is selected via environment 'videoout' 1812 (1 = LCD and 2 = CRT). If videoout is undefined, CRT is 1813 assumed. 1814 1815 For the CT69000 and SMI_LYNXEM drivers, videomode is 1816 selected via environment 'videomode'. Two different ways 1817 are possible: 1818 - "videomode=num" 'num' is a standard LiLo mode numbers. 1819 Following standard modes are supported (* is default): 1820 1821 Colors 640x480 800x600 1024x768 1152x864 1280x1024 1822 -------------+--------------------------------------------- 1823 8 bits | 0x301* 0x303 0x305 0x161 0x307 1824 15 bits | 0x310 0x313 0x316 0x162 0x319 1825 16 bits | 0x311 0x314 0x317 0x163 0x31A 1826 24 bits | 0x312 0x315 0x318 ? 0x31B 1827 -------------+--------------------------------------------- 1828 (i.e. setenv videomode 317; saveenv; reset;) 1829 1830 - "videomode=bootargs" all the video parameters are parsed 1831 from the bootargs. (See drivers/video/videomodes.c) 1832 1833 1834 CONFIG_VIDEO_SED13806 1835 Enable Epson SED13806 driver. This driver supports 8bpp 1836 and 16bpp modes defined by CONFIG_VIDEO_SED13806_8BPP 1837 or CONFIG_VIDEO_SED13806_16BPP 1838 1839 CONFIG_FSL_DIU_FB 1840 Enable the Freescale DIU video driver. Reference boards for 1841 SOCs that have a DIU should define this macro to enable DIU 1842 support, and should also define these other macros: 1843 1844 CONFIG_SYS_DIU_ADDR 1845 CONFIG_VIDEO 1846 CONFIG_CMD_BMP 1847 CONFIG_CFB_CONSOLE 1848 CONFIG_VIDEO_SW_CURSOR 1849 CONFIG_VGA_AS_SINGLE_DEVICE 1850 CONFIG_VIDEO_LOGO 1851 CONFIG_VIDEO_BMP_LOGO 1852 1853 The DIU driver will look for the 'video-mode' environment 1854 variable, and if defined, enable the DIU as a console during 1855 boot. See the documentation file README.video for a 1856 description of this variable. 1857 1858 1859- Keyboard Support: 1860 CONFIG_KEYBOARD 1861 1862 Define this to enable a custom keyboard support. 1863 This simply calls drv_keyboard_init() which must be 1864 defined in your board-specific files. 1865 The only board using this so far is RBC823. 1866 1867- LCD Support: CONFIG_LCD 1868 1869 Define this to enable LCD support (for output to LCD 1870 display); also select one of the supported displays 1871 by defining one of these: 1872 1873 CONFIG_ATMEL_LCD: 1874 1875 HITACHI TX09D70VM1CCA, 3.5", 240x320. 1876 1877 CONFIG_NEC_NL6448AC33: 1878 1879 NEC NL6448AC33-18. Active, color, single scan. 1880 1881 CONFIG_NEC_NL6448BC20 1882 1883 NEC NL6448BC20-08. 6.5", 640x480. 1884 Active, color, single scan. 1885 1886 CONFIG_NEC_NL6448BC33_54 1887 1888 NEC NL6448BC33-54. 10.4", 640x480. 1889 Active, color, single scan. 1890 1891 CONFIG_SHARP_16x9 1892 1893 Sharp 320x240. Active, color, single scan. 1894 It isn't 16x9, and I am not sure what it is. 1895 1896 CONFIG_SHARP_LQ64D341 1897 1898 Sharp LQ64D341 display, 640x480. 1899 Active, color, single scan. 1900 1901 CONFIG_HLD1045 1902 1903 HLD1045 display, 640x480. 1904 Active, color, single scan. 1905 1906 CONFIG_OPTREX_BW 1907 1908 Optrex CBL50840-2 NF-FW 99 22 M5 1909 or 1910 Hitachi LMG6912RPFC-00T 1911 or 1912 Hitachi SP14Q002 1913 1914 320x240. Black & white. 1915 1916 Normally display is black on white background; define 1917 CONFIG_SYS_WHITE_ON_BLACK to get it inverted. 1918 1919 CONFIG_LCD_ALIGNMENT 1920 1921 Normally the LCD is page-aligned (typically 4KB). If this is 1922 defined then the LCD will be aligned to this value instead. 1923 For ARM it is sometimes useful to use MMU_SECTION_SIZE 1924 here, since it is cheaper to change data cache settings on 1925 a per-section basis. 1926 1927 CONFIG_CONSOLE_SCROLL_LINES 1928 1929 When the console need to be scrolled, this is the number of 1930 lines to scroll by. It defaults to 1. Increasing this makes 1931 the console jump but can help speed up operation when scrolling 1932 is slow. 1933 1934 CONFIG_LCD_ROTATION 1935 1936 Sometimes, for example if the display is mounted in portrait 1937 mode or even if it's mounted landscape but rotated by 180degree, 1938 we need to rotate our content of the display relative to the 1939 framebuffer, so that user can read the messages which are 1940 printed out. 1941 Once CONFIG_LCD_ROTATION is defined, the lcd_console will be 1942 initialized with a given rotation from "vl_rot" out of 1943 "vidinfo_t" which is provided by the board specific code. 1944 The value for vl_rot is coded as following (matching to 1945 fbcon=rotate:<n> linux-kernel commandline): 1946 0 = no rotation respectively 0 degree 1947 1 = 90 degree rotation 1948 2 = 180 degree rotation 1949 3 = 270 degree rotation 1950 1951 If CONFIG_LCD_ROTATION is not defined, the console will be 1952 initialized with 0degree rotation. 1953 1954 CONFIG_LCD_BMP_RLE8 1955 1956 Support drawing of RLE8-compressed bitmaps on the LCD. 1957 1958 CONFIG_I2C_EDID 1959 1960 Enables an 'i2c edid' command which can read EDID 1961 information over I2C from an attached LCD display. 1962 1963- Splash Screen Support: CONFIG_SPLASH_SCREEN 1964 1965 If this option is set, the environment is checked for 1966 a variable "splashimage". If found, the usual display 1967 of logo, copyright and system information on the LCD 1968 is suppressed and the BMP image at the address 1969 specified in "splashimage" is loaded instead. The 1970 console is redirected to the "nulldev", too. This 1971 allows for a "silent" boot where a splash screen is 1972 loaded very quickly after power-on. 1973 1974 CONFIG_SPLASHIMAGE_GUARD 1975 1976 If this option is set, then U-Boot will prevent the environment 1977 variable "splashimage" from being set to a problematic address 1978 (see README.displaying-bmps). 1979 This option is useful for targets where, due to alignment 1980 restrictions, an improperly aligned BMP image will cause a data 1981 abort. If you think you will not have problems with unaligned 1982 accesses (for example because your toolchain prevents them) 1983 there is no need to set this option. 1984 1985 CONFIG_SPLASH_SCREEN_ALIGN 1986 1987 If this option is set the splash image can be freely positioned 1988 on the screen. Environment variable "splashpos" specifies the 1989 position as "x,y". If a positive number is given it is used as 1990 number of pixel from left/top. If a negative number is given it 1991 is used as number of pixel from right/bottom. You can also 1992 specify 'm' for centering the image. 1993 1994 Example: 1995 setenv splashpos m,m 1996 => image at center of screen 1997 1998 setenv splashpos 30,20 1999 => image at x = 30 and y = 20 2000 2001 setenv splashpos -10,m 2002 => vertically centered image 2003 at x = dspWidth - bmpWidth - 9 2004 2005- Gzip compressed BMP image support: CONFIG_VIDEO_BMP_GZIP 2006 2007 If this option is set, additionally to standard BMP 2008 images, gzipped BMP images can be displayed via the 2009 splashscreen support or the bmp command. 2010 2011- Run length encoded BMP image (RLE8) support: CONFIG_VIDEO_BMP_RLE8 2012 2013 If this option is set, 8-bit RLE compressed BMP images 2014 can be displayed via the splashscreen support or the 2015 bmp command. 2016 2017- Do compressing for memory range: 2018 CONFIG_CMD_ZIP 2019 2020 If this option is set, it would use zlib deflate method 2021 to compress the specified memory at its best effort. 2022 2023- Compression support: 2024 CONFIG_GZIP 2025 2026 Enabled by default to support gzip compressed images. 2027 2028 CONFIG_BZIP2 2029 2030 If this option is set, support for bzip2 compressed 2031 images is included. If not, only uncompressed and gzip 2032 compressed images are supported. 2033 2034 NOTE: the bzip2 algorithm requires a lot of RAM, so 2035 the malloc area (as defined by CONFIG_SYS_MALLOC_LEN) should 2036 be at least 4MB. 2037 2038 CONFIG_LZMA 2039 2040 If this option is set, support for lzma compressed 2041 images is included. 2042 2043 Note: The LZMA algorithm adds between 2 and 4KB of code and it 2044 requires an amount of dynamic memory that is given by the 2045 formula: 2046 2047 (1846 + 768 << (lc + lp)) * sizeof(uint16) 2048 2049 Where lc and lp stand for, respectively, Literal context bits 2050 and Literal pos bits. 2051 2052 This value is upper-bounded by 14MB in the worst case. Anyway, 2053 for a ~4MB large kernel image, we have lc=3 and lp=0 for a 2054 total amount of (1846 + 768 << (3 + 0)) * 2 = ~41KB... that is 2055 a very small buffer. 2056 2057 Use the lzmainfo tool to determinate the lc and lp values and 2058 then calculate the amount of needed dynamic memory (ensuring 2059 the appropriate CONFIG_SYS_MALLOC_LEN value). 2060 2061 CONFIG_LZO 2062 2063 If this option is set, support for LZO compressed images 2064 is included. 2065 2066- MII/PHY support: 2067 CONFIG_PHY_ADDR 2068 2069 The address of PHY on MII bus. 2070 2071 CONFIG_PHY_CLOCK_FREQ (ppc4xx) 2072 2073 The clock frequency of the MII bus 2074 2075 CONFIG_PHY_GIGE 2076 2077 If this option is set, support for speed/duplex 2078 detection of gigabit PHY is included. 2079 2080 CONFIG_PHY_RESET_DELAY 2081 2082 Some PHY like Intel LXT971A need extra delay after 2083 reset before any MII register access is possible. 2084 For such PHY, set this option to the usec delay 2085 required. (minimum 300usec for LXT971A) 2086 2087 CONFIG_PHY_CMD_DELAY (ppc4xx) 2088 2089 Some PHY like Intel LXT971A need extra delay after 2090 command issued before MII status register can be read 2091 2092- IP address: 2093 CONFIG_IPADDR 2094 2095 Define a default value for the IP address to use for 2096 the default Ethernet interface, in case this is not 2097 determined through e.g. bootp. 2098 (Environment variable "ipaddr") 2099 2100- Server IP address: 2101 CONFIG_SERVERIP 2102 2103 Defines a default value for the IP address of a TFTP 2104 server to contact when using the "tftboot" command. 2105 (Environment variable "serverip") 2106 2107 CONFIG_KEEP_SERVERADDR 2108 2109 Keeps the server's MAC address, in the env 'serveraddr' 2110 for passing to bootargs (like Linux's netconsole option) 2111 2112- Gateway IP address: 2113 CONFIG_GATEWAYIP 2114 2115 Defines a default value for the IP address of the 2116 default router where packets to other networks are 2117 sent to. 2118 (Environment variable "gatewayip") 2119 2120- Subnet mask: 2121 CONFIG_NETMASK 2122 2123 Defines a default value for the subnet mask (or 2124 routing prefix) which is used to determine if an IP 2125 address belongs to the local subnet or needs to be 2126 forwarded through a router. 2127 (Environment variable "netmask") 2128 2129- Multicast TFTP Mode: 2130 CONFIG_MCAST_TFTP 2131 2132 Defines whether you want to support multicast TFTP as per 2133 rfc-2090; for example to work with atftp. Lets lots of targets 2134 tftp down the same boot image concurrently. Note: the Ethernet 2135 driver in use must provide a function: mcast() to join/leave a 2136 multicast group. 2137 2138- BOOTP Recovery Mode: 2139 CONFIG_BOOTP_RANDOM_DELAY 2140 2141 If you have many targets in a network that try to 2142 boot using BOOTP, you may want to avoid that all 2143 systems send out BOOTP requests at precisely the same 2144 moment (which would happen for instance at recovery 2145 from a power failure, when all systems will try to 2146 boot, thus flooding the BOOTP server. Defining 2147 CONFIG_BOOTP_RANDOM_DELAY causes a random delay to be 2148 inserted before sending out BOOTP requests. The 2149 following delays are inserted then: 2150 2151 1st BOOTP request: delay 0 ... 1 sec 2152 2nd BOOTP request: delay 0 ... 2 sec 2153 3rd BOOTP request: delay 0 ... 4 sec 2154 4th and following 2155 BOOTP requests: delay 0 ... 8 sec 2156 2157 CONFIG_BOOTP_ID_CACHE_SIZE 2158 2159 BOOTP packets are uniquely identified using a 32-bit ID. The 2160 server will copy the ID from client requests to responses and 2161 U-Boot will use this to determine if it is the destination of 2162 an incoming response. Some servers will check that addresses 2163 aren't in use before handing them out (usually using an ARP 2164 ping) and therefore take up to a few hundred milliseconds to 2165 respond. Network congestion may also influence the time it 2166 takes for a response to make it back to the client. If that 2167 time is too long, U-Boot will retransmit requests. In order 2168 to allow earlier responses to still be accepted after these 2169 retransmissions, U-Boot's BOOTP client keeps a small cache of 2170 IDs. The CONFIG_BOOTP_ID_CACHE_SIZE controls the size of this 2171 cache. The default is to keep IDs for up to four outstanding 2172 requests. Increasing this will allow U-Boot to accept offers 2173 from a BOOTP client in networks with unusually high latency. 2174 2175- DHCP Advanced Options: 2176 You can fine tune the DHCP functionality by defining 2177 CONFIG_BOOTP_* symbols: 2178 2179 CONFIG_BOOTP_SUBNETMASK 2180 CONFIG_BOOTP_GATEWAY 2181 CONFIG_BOOTP_HOSTNAME 2182 CONFIG_BOOTP_NISDOMAIN 2183 CONFIG_BOOTP_BOOTPATH 2184 CONFIG_BOOTP_BOOTFILESIZE 2185 CONFIG_BOOTP_DNS 2186 CONFIG_BOOTP_DNS2 2187 CONFIG_BOOTP_SEND_HOSTNAME 2188 CONFIG_BOOTP_NTPSERVER 2189 CONFIG_BOOTP_TIMEOFFSET 2190 CONFIG_BOOTP_VENDOREX 2191 CONFIG_BOOTP_MAY_FAIL 2192 2193 CONFIG_BOOTP_SERVERIP - TFTP server will be the serverip 2194 environment variable, not the BOOTP server. 2195 2196 CONFIG_BOOTP_MAY_FAIL - If the DHCP server is not found 2197 after the configured retry count, the call will fail 2198 instead of starting over. This can be used to fail over 2199 to Link-local IP address configuration if the DHCP server 2200 is not available. 2201 2202 CONFIG_BOOTP_DNS2 - If a DHCP client requests the DNS 2203 serverip from a DHCP server, it is possible that more 2204 than one DNS serverip is offered to the client. 2205 If CONFIG_BOOTP_DNS2 is enabled, the secondary DNS 2206 serverip will be stored in the additional environment 2207 variable "dnsip2". The first DNS serverip is always 2208 stored in the variable "dnsip", when CONFIG_BOOTP_DNS 2209 is defined. 2210 2211 CONFIG_BOOTP_SEND_HOSTNAME - Some DHCP servers are capable 2212 to do a dynamic update of a DNS server. To do this, they 2213 need the hostname of the DHCP requester. 2214 If CONFIG_BOOTP_SEND_HOSTNAME is defined, the content 2215 of the "hostname" environment variable is passed as 2216 option 12 to the DHCP server. 2217 2218 CONFIG_BOOTP_DHCP_REQUEST_DELAY 2219 2220 A 32bit value in microseconds for a delay between 2221 receiving a "DHCP Offer" and sending the "DHCP Request". 2222 This fixes a problem with certain DHCP servers that don't 2223 respond 100% of the time to a "DHCP request". E.g. On an 2224 AT91RM9200 processor running at 180MHz, this delay needed 2225 to be *at least* 15,000 usec before a Windows Server 2003 2226 DHCP server would reply 100% of the time. I recommend at 2227 least 50,000 usec to be safe. The alternative is to hope 2228 that one of the retries will be successful but note that 2229 the DHCP timeout and retry process takes a longer than 2230 this delay. 2231 2232 - Link-local IP address negotiation: 2233 Negotiate with other link-local clients on the local network 2234 for an address that doesn't require explicit configuration. 2235 This is especially useful if a DHCP server cannot be guaranteed 2236 to exist in all environments that the device must operate. 2237 2238 See doc/README.link-local for more information. 2239 2240 - CDP Options: 2241 CONFIG_CDP_DEVICE_ID 2242 2243 The device id used in CDP trigger frames. 2244 2245 CONFIG_CDP_DEVICE_ID_PREFIX 2246 2247 A two character string which is prefixed to the MAC address 2248 of the device. 2249 2250 CONFIG_CDP_PORT_ID 2251 2252 A printf format string which contains the ascii name of 2253 the port. Normally is set to "eth%d" which sets 2254 eth0 for the first Ethernet, eth1 for the second etc. 2255 2256 CONFIG_CDP_CAPABILITIES 2257 2258 A 32bit integer which indicates the device capabilities; 2259 0x00000010 for a normal host which does not forwards. 2260 2261 CONFIG_CDP_VERSION 2262 2263 An ascii string containing the version of the software. 2264 2265 CONFIG_CDP_PLATFORM 2266 2267 An ascii string containing the name of the platform. 2268 2269 CONFIG_CDP_TRIGGER 2270 2271 A 32bit integer sent on the trigger. 2272 2273 CONFIG_CDP_POWER_CONSUMPTION 2274 2275 A 16bit integer containing the power consumption of the 2276 device in .1 of milliwatts. 2277 2278 CONFIG_CDP_APPLIANCE_VLAN_TYPE 2279 2280 A byte containing the id of the VLAN. 2281 2282- Status LED: CONFIG_STATUS_LED 2283 2284 Several configurations allow to display the current 2285 status using a LED. For instance, the LED will blink 2286 fast while running U-Boot code, stop blinking as 2287 soon as a reply to a BOOTP request was received, and 2288 start blinking slow once the Linux kernel is running 2289 (supported by a status LED driver in the Linux 2290 kernel). Defining CONFIG_STATUS_LED enables this 2291 feature in U-Boot. 2292 2293 Additional options: 2294 2295 CONFIG_GPIO_LED 2296 The status LED can be connected to a GPIO pin. 2297 In such cases, the gpio_led driver can be used as a 2298 status LED backend implementation. Define CONFIG_GPIO_LED 2299 to include the gpio_led driver in the U-Boot binary. 2300 2301 CONFIG_GPIO_LED_INVERTED_TABLE 2302 Some GPIO connected LEDs may have inverted polarity in which 2303 case the GPIO high value corresponds to LED off state and 2304 GPIO low value corresponds to LED on state. 2305 In such cases CONFIG_GPIO_LED_INVERTED_TABLE may be defined 2306 with a list of GPIO LEDs that have inverted polarity. 2307 2308- CAN Support: CONFIG_CAN_DRIVER 2309 2310 Defining CONFIG_CAN_DRIVER enables CAN driver support 2311 on those systems that support this (optional) 2312 feature, like the TQM8xxL modules. 2313 2314- I2C Support: CONFIG_SYS_I2C 2315 2316 This enable the NEW i2c subsystem, and will allow you to use 2317 i2c commands at the u-boot command line (as long as you set 2318 CONFIG_CMD_I2C in CONFIG_COMMANDS) and communicate with i2c 2319 based realtime clock chips or other i2c devices. See 2320 common/cmd_i2c.c for a description of the command line 2321 interface. 2322 2323 ported i2c driver to the new framework: 2324 - drivers/i2c/soft_i2c.c: 2325 - activate first bus with CONFIG_SYS_I2C_SOFT define 2326 CONFIG_SYS_I2C_SOFT_SPEED and CONFIG_SYS_I2C_SOFT_SLAVE 2327 for defining speed and slave address 2328 - activate second bus with I2C_SOFT_DECLARATIONS2 define 2329 CONFIG_SYS_I2C_SOFT_SPEED_2 and CONFIG_SYS_I2C_SOFT_SLAVE_2 2330 for defining speed and slave address 2331 - activate third bus with I2C_SOFT_DECLARATIONS3 define 2332 CONFIG_SYS_I2C_SOFT_SPEED_3 and CONFIG_SYS_I2C_SOFT_SLAVE_3 2333 for defining speed and slave address 2334 - activate fourth bus with I2C_SOFT_DECLARATIONS4 define 2335 CONFIG_SYS_I2C_SOFT_SPEED_4 and CONFIG_SYS_I2C_SOFT_SLAVE_4 2336 for defining speed and slave address 2337 2338 - drivers/i2c/fsl_i2c.c: 2339 - activate i2c driver with CONFIG_SYS_I2C_FSL 2340 define CONFIG_SYS_FSL_I2C_OFFSET for setting the register 2341 offset CONFIG_SYS_FSL_I2C_SPEED for the i2c speed and 2342 CONFIG_SYS_FSL_I2C_SLAVE for the slave addr of the first 2343 bus. 2344 - If your board supports a second fsl i2c bus, define 2345 CONFIG_SYS_FSL_I2C2_OFFSET for the register offset 2346 CONFIG_SYS_FSL_I2C2_SPEED for the speed and 2347 CONFIG_SYS_FSL_I2C2_SLAVE for the slave address of the 2348 second bus. 2349 2350 - drivers/i2c/tegra_i2c.c: 2351 - activate this driver with CONFIG_SYS_I2C_TEGRA 2352 - This driver adds 4 i2c buses with a fix speed from 2353 100000 and the slave addr 0! 2354 2355 - drivers/i2c/ppc4xx_i2c.c 2356 - activate this driver with CONFIG_SYS_I2C_PPC4XX 2357 - CONFIG_SYS_I2C_PPC4XX_CH0 activate hardware channel 0 2358 - CONFIG_SYS_I2C_PPC4XX_CH1 activate hardware channel 1 2359 2360 - drivers/i2c/i2c_mxc.c 2361 - activate this driver with CONFIG_SYS_I2C_MXC 2362 - enable bus 1 with CONFIG_SYS_I2C_MXC_I2C1 2363 - enable bus 2 with CONFIG_SYS_I2C_MXC_I2C2 2364 - enable bus 3 with CONFIG_SYS_I2C_MXC_I2C3 2365 - enable bus 4 with CONFIG_SYS_I2C_MXC_I2C4 2366 - define speed for bus 1 with CONFIG_SYS_MXC_I2C1_SPEED 2367 - define slave for bus 1 with CONFIG_SYS_MXC_I2C1_SLAVE 2368 - define speed for bus 2 with CONFIG_SYS_MXC_I2C2_SPEED 2369 - define slave for bus 2 with CONFIG_SYS_MXC_I2C2_SLAVE 2370 - define speed for bus 3 with CONFIG_SYS_MXC_I2C3_SPEED 2371 - define slave for bus 3 with CONFIG_SYS_MXC_I2C3_SLAVE 2372 - define speed for bus 4 with CONFIG_SYS_MXC_I2C4_SPEED 2373 - define slave for bus 4 with CONFIG_SYS_MXC_I2C4_SLAVE 2374 If those defines are not set, default value is 100000 2375 for speed, and 0 for slave. 2376 2377 - drivers/i2c/rcar_i2c.c: 2378 - activate this driver with CONFIG_SYS_I2C_RCAR 2379 - This driver adds 4 i2c buses 2380 2381 - CONFIG_SYS_RCAR_I2C0_BASE for setting the register channel 0 2382 - CONFIG_SYS_RCAR_I2C0_SPEED for for the speed channel 0 2383 - CONFIG_SYS_RCAR_I2C1_BASE for setting the register channel 1 2384 - CONFIG_SYS_RCAR_I2C1_SPEED for for the speed channel 1 2385 - CONFIG_SYS_RCAR_I2C2_BASE for setting the register channel 2 2386 - CONFIG_SYS_RCAR_I2C2_SPEED for for the speed channel 2 2387 - CONFIG_SYS_RCAR_I2C3_BASE for setting the register channel 3 2388 - CONFIG_SYS_RCAR_I2C3_SPEED for for the speed channel 3 2389 - CONFIF_SYS_RCAR_I2C_NUM_CONTROLLERS for number of i2c buses 2390 2391 - drivers/i2c/sh_i2c.c: 2392 - activate this driver with CONFIG_SYS_I2C_SH 2393 - This driver adds from 2 to 5 i2c buses 2394 2395 - CONFIG_SYS_I2C_SH_BASE0 for setting the register channel 0 2396 - CONFIG_SYS_I2C_SH_SPEED0 for for the speed channel 0 2397 - CONFIG_SYS_I2C_SH_BASE1 for setting the register channel 1 2398 - CONFIG_SYS_I2C_SH_SPEED1 for for the speed channel 1 2399 - CONFIG_SYS_I2C_SH_BASE2 for setting the register channel 2 2400 - CONFIG_SYS_I2C_SH_SPEED2 for for the speed channel 2 2401 - CONFIG_SYS_I2C_SH_BASE3 for setting the register channel 3 2402 - CONFIG_SYS_I2C_SH_SPEED3 for for the speed channel 3 2403 - CONFIG_SYS_I2C_SH_BASE4 for setting the register channel 4 2404 - CONFIG_SYS_I2C_SH_SPEED4 for for the speed channel 4 2405 - CONFIG_SYS_I2C_SH_BASE5 for setting the register channel 5 2406 - CONFIG_SYS_I2C_SH_SPEED5 for for the speed channel 5 2407 - CONFIG_SYS_I2C_SH_NUM_CONTROLLERS for number of i2c buses 2408 2409 - drivers/i2c/omap24xx_i2c.c 2410 - activate this driver with CONFIG_SYS_I2C_OMAP24XX 2411 - CONFIG_SYS_OMAP24_I2C_SPEED speed channel 0 2412 - CONFIG_SYS_OMAP24_I2C_SLAVE slave addr channel 0 2413 - CONFIG_SYS_OMAP24_I2C_SPEED1 speed channel 1 2414 - CONFIG_SYS_OMAP24_I2C_SLAVE1 slave addr channel 1 2415 - CONFIG_SYS_OMAP24_I2C_SPEED2 speed channel 2 2416 - CONFIG_SYS_OMAP24_I2C_SLAVE2 slave addr channel 2 2417 - CONFIG_SYS_OMAP24_I2C_SPEED3 speed channel 3 2418 - CONFIG_SYS_OMAP24_I2C_SLAVE3 slave addr channel 3 2419 - CONFIG_SYS_OMAP24_I2C_SPEED4 speed channel 4 2420 - CONFIG_SYS_OMAP24_I2C_SLAVE4 slave addr channel 4 2421 2422 - drivers/i2c/zynq_i2c.c 2423 - activate this driver with CONFIG_SYS_I2C_ZYNQ 2424 - set CONFIG_SYS_I2C_ZYNQ_SPEED for speed setting 2425 - set CONFIG_SYS_I2C_ZYNQ_SLAVE for slave addr 2426 2427 - drivers/i2c/s3c24x0_i2c.c: 2428 - activate this driver with CONFIG_SYS_I2C_S3C24X0 2429 - This driver adds i2c buses (11 for Exynos5250, Exynos5420 2430 9 i2c buses for Exynos4 and 1 for S3C24X0 SoCs from Samsung) 2431 with a fix speed from 100000 and the slave addr 0! 2432 2433 - drivers/i2c/ihs_i2c.c 2434 - activate this driver with CONFIG_SYS_I2C_IHS 2435 - CONFIG_SYS_I2C_IHS_CH0 activate hardware channel 0 2436 - CONFIG_SYS_I2C_IHS_SPEED_0 speed channel 0 2437 - CONFIG_SYS_I2C_IHS_SLAVE_0 slave addr channel 0 2438 - CONFIG_SYS_I2C_IHS_CH1 activate hardware channel 1 2439 - CONFIG_SYS_I2C_IHS_SPEED_1 speed channel 1 2440 - CONFIG_SYS_I2C_IHS_SLAVE_1 slave addr channel 1 2441 - CONFIG_SYS_I2C_IHS_CH2 activate hardware channel 2 2442 - CONFIG_SYS_I2C_IHS_SPEED_2 speed channel 2 2443 - CONFIG_SYS_I2C_IHS_SLAVE_2 slave addr channel 2 2444 - CONFIG_SYS_I2C_IHS_CH3 activate hardware channel 3 2445 - CONFIG_SYS_I2C_IHS_SPEED_3 speed channel 3 2446 - CONFIG_SYS_I2C_IHS_SLAVE_3 slave addr channel 3 2447 2448 additional defines: 2449 2450 CONFIG_SYS_NUM_I2C_BUSES 2451 Hold the number of i2c buses you want to use. If you 2452 don't use/have i2c muxes on your i2c bus, this 2453 is equal to CONFIG_SYS_NUM_I2C_ADAPTERS, and you can 2454 omit this define. 2455 2456 CONFIG_SYS_I2C_DIRECT_BUS 2457 define this, if you don't use i2c muxes on your hardware. 2458 if CONFIG_SYS_I2C_MAX_HOPS is not defined or == 0 you can 2459 omit this define. 2460 2461 CONFIG_SYS_I2C_MAX_HOPS 2462 define how many muxes are maximal consecutively connected 2463 on one i2c bus. If you not use i2c muxes, omit this 2464 define. 2465 2466 CONFIG_SYS_I2C_BUSES 2467 hold a list of buses you want to use, only used if 2468 CONFIG_SYS_I2C_DIRECT_BUS is not defined, for example 2469 a board with CONFIG_SYS_I2C_MAX_HOPS = 1 and 2470 CONFIG_SYS_NUM_I2C_BUSES = 9: 2471 2472 CONFIG_SYS_I2C_BUSES {{0, {I2C_NULL_HOP}}, \ 2473 {0, {{I2C_MUX_PCA9547, 0x70, 1}}}, \ 2474 {0, {{I2C_MUX_PCA9547, 0x70, 2}}}, \ 2475 {0, {{I2C_MUX_PCA9547, 0x70, 3}}}, \ 2476 {0, {{I2C_MUX_PCA9547, 0x70, 4}}}, \ 2477 {0, {{I2C_MUX_PCA9547, 0x70, 5}}}, \ 2478 {1, {I2C_NULL_HOP}}, \ 2479 {1, {{I2C_MUX_PCA9544, 0x72, 1}}}, \ 2480 {1, {{I2C_MUX_PCA9544, 0x72, 2}}}, \ 2481 } 2482 2483 which defines 2484 bus 0 on adapter 0 without a mux 2485 bus 1 on adapter 0 with a PCA9547 on address 0x70 port 1 2486 bus 2 on adapter 0 with a PCA9547 on address 0x70 port 2 2487 bus 3 on adapter 0 with a PCA9547 on address 0x70 port 3 2488 bus 4 on adapter 0 with a PCA9547 on address 0x70 port 4 2489 bus 5 on adapter 0 with a PCA9547 on address 0x70 port 5 2490 bus 6 on adapter 1 without a mux 2491 bus 7 on adapter 1 with a PCA9544 on address 0x72 port 1 2492 bus 8 on adapter 1 with a PCA9544 on address 0x72 port 2 2493 2494 If you do not have i2c muxes on your board, omit this define. 2495 2496- Legacy I2C Support: CONFIG_HARD_I2C 2497 2498 NOTE: It is intended to move drivers to CONFIG_SYS_I2C which 2499 provides the following compelling advantages: 2500 2501 - more than one i2c adapter is usable 2502 - approved multibus support 2503 - better i2c mux support 2504 2505 ** Please consider updating your I2C driver now. ** 2506 2507 These enable legacy I2C serial bus commands. Defining 2508 CONFIG_HARD_I2C will include the appropriate I2C driver 2509 for the selected CPU. 2510 2511 This will allow you to use i2c commands at the u-boot 2512 command line (as long as you set CONFIG_CMD_I2C in 2513 CONFIG_COMMANDS) and communicate with i2c based realtime 2514 clock chips. See common/cmd_i2c.c for a description of the 2515 command line interface. 2516 2517 CONFIG_HARD_I2C selects a hardware I2C controller. 2518 2519 There are several other quantities that must also be 2520 defined when you define CONFIG_HARD_I2C. 2521 2522 In both cases you will need to define CONFIG_SYS_I2C_SPEED 2523 to be the frequency (in Hz) at which you wish your i2c bus 2524 to run and CONFIG_SYS_I2C_SLAVE to be the address of this node (ie 2525 the CPU's i2c node address). 2526 2527 Now, the u-boot i2c code for the mpc8xx 2528 (arch/powerpc/cpu/mpc8xx/i2c.c) sets the CPU up as a master node 2529 and so its address should therefore be cleared to 0 (See, 2530 eg, MPC823e User's Manual p.16-473). So, set 2531 CONFIG_SYS_I2C_SLAVE to 0. 2532 2533 CONFIG_SYS_I2C_INIT_MPC5XXX 2534 2535 When a board is reset during an i2c bus transfer 2536 chips might think that the current transfer is still 2537 in progress. Reset the slave devices by sending start 2538 commands until the slave device responds. 2539 2540 That's all that's required for CONFIG_HARD_I2C. 2541 2542 If you use the software i2c interface (CONFIG_SYS_I2C_SOFT) 2543 then the following macros need to be defined (examples are 2544 from include/configs/lwmon.h): 2545 2546 I2C_INIT 2547 2548 (Optional). Any commands necessary to enable the I2C 2549 controller or configure ports. 2550 2551 eg: #define I2C_INIT (immr->im_cpm.cp_pbdir |= PB_SCL) 2552 2553 I2C_PORT 2554 2555 (Only for MPC8260 CPU). The I/O port to use (the code 2556 assumes both bits are on the same port). Valid values 2557 are 0..3 for ports A..D. 2558 2559 I2C_ACTIVE 2560 2561 The code necessary to make the I2C data line active 2562 (driven). If the data line is open collector, this 2563 define can be null. 2564 2565 eg: #define I2C_ACTIVE (immr->im_cpm.cp_pbdir |= PB_SDA) 2566 2567 I2C_TRISTATE 2568 2569 The code necessary to make the I2C data line tri-stated 2570 (inactive). If the data line is open collector, this 2571 define can be null. 2572 2573 eg: #define I2C_TRISTATE (immr->im_cpm.cp_pbdir &= ~PB_SDA) 2574 2575 I2C_READ 2576 2577 Code that returns true if the I2C data line is high, 2578 false if it is low. 2579 2580 eg: #define I2C_READ ((immr->im_cpm.cp_pbdat & PB_SDA) != 0) 2581 2582 I2C_SDA(bit) 2583 2584 If <bit> is true, sets the I2C data line high. If it 2585 is false, it clears it (low). 2586 2587 eg: #define I2C_SDA(bit) \ 2588 if(bit) immr->im_cpm.cp_pbdat |= PB_SDA; \ 2589 else immr->im_cpm.cp_pbdat &= ~PB_SDA 2590 2591 I2C_SCL(bit) 2592 2593 If <bit> is true, sets the I2C clock line high. If it 2594 is false, it clears it (low). 2595 2596 eg: #define I2C_SCL(bit) \ 2597 if(bit) immr->im_cpm.cp_pbdat |= PB_SCL; \ 2598 else immr->im_cpm.cp_pbdat &= ~PB_SCL 2599 2600 I2C_DELAY 2601 2602 This delay is invoked four times per clock cycle so this 2603 controls the rate of data transfer. The data rate thus 2604 is 1 / (I2C_DELAY * 4). Often defined to be something 2605 like: 2606 2607 #define I2C_DELAY udelay(2) 2608 2609 CONFIG_SOFT_I2C_GPIO_SCL / CONFIG_SOFT_I2C_GPIO_SDA 2610 2611 If your arch supports the generic GPIO framework (asm/gpio.h), 2612 then you may alternatively define the two GPIOs that are to be 2613 used as SCL / SDA. Any of the previous I2C_xxx macros will 2614 have GPIO-based defaults assigned to them as appropriate. 2615 2616 You should define these to the GPIO value as given directly to 2617 the generic GPIO functions. 2618 2619 CONFIG_SYS_I2C_INIT_BOARD 2620 2621 When a board is reset during an i2c bus transfer 2622 chips might think that the current transfer is still 2623 in progress. On some boards it is possible to access 2624 the i2c SCLK line directly, either by using the 2625 processor pin as a GPIO or by having a second pin 2626 connected to the bus. If this option is defined a 2627 custom i2c_init_board() routine in boards/xxx/board.c 2628 is run early in the boot sequence. 2629 2630 CONFIG_SYS_I2C_BOARD_LATE_INIT 2631 2632 An alternative to CONFIG_SYS_I2C_INIT_BOARD. If this option is 2633 defined a custom i2c_board_late_init() routine in 2634 boards/xxx/board.c is run AFTER the operations in i2c_init() 2635 is completed. This callpoint can be used to unreset i2c bus 2636 using CPU i2c controller register accesses for CPUs whose i2c 2637 controller provide such a method. It is called at the end of 2638 i2c_init() to allow i2c_init operations to setup the i2c bus 2639 controller on the CPU (e.g. setting bus speed & slave address). 2640 2641 CONFIG_I2CFAST (PPC405GP|PPC405EP only) 2642 2643 This option enables configuration of bi_iic_fast[] flags 2644 in u-boot bd_info structure based on u-boot environment 2645 variable "i2cfast". (see also i2cfast) 2646 2647 CONFIG_I2C_MULTI_BUS 2648 2649 This option allows the use of multiple I2C buses, each of which 2650 must have a controller. At any point in time, only one bus is 2651 active. To switch to a different bus, use the 'i2c dev' command. 2652 Note that bus numbering is zero-based. 2653 2654 CONFIG_SYS_I2C_NOPROBES 2655 2656 This option specifies a list of I2C devices that will be skipped 2657 when the 'i2c probe' command is issued. If CONFIG_I2C_MULTI_BUS 2658 is set, specify a list of bus-device pairs. Otherwise, specify 2659 a 1D array of device addresses 2660 2661 e.g. 2662 #undef CONFIG_I2C_MULTI_BUS 2663 #define CONFIG_SYS_I2C_NOPROBES {0x50,0x68} 2664 2665 will skip addresses 0x50 and 0x68 on a board with one I2C bus 2666 2667 #define CONFIG_I2C_MULTI_BUS 2668 #define CONFIG_SYS_I2C_MULTI_NOPROBES {{0,0x50},{0,0x68},{1,0x54}} 2669 2670 will skip addresses 0x50 and 0x68 on bus 0 and address 0x54 on bus 1 2671 2672 CONFIG_SYS_SPD_BUS_NUM 2673 2674 If defined, then this indicates the I2C bus number for DDR SPD. 2675 If not defined, then U-Boot assumes that SPD is on I2C bus 0. 2676 2677 CONFIG_SYS_RTC_BUS_NUM 2678 2679 If defined, then this indicates the I2C bus number for the RTC. 2680 If not defined, then U-Boot assumes that RTC is on I2C bus 0. 2681 2682 CONFIG_SYS_DTT_BUS_NUM 2683 2684 If defined, then this indicates the I2C bus number for the DTT. 2685 If not defined, then U-Boot assumes that DTT is on I2C bus 0. 2686 2687 CONFIG_SYS_I2C_DTT_ADDR: 2688 2689 If defined, specifies the I2C address of the DTT device. 2690 If not defined, then U-Boot uses predefined value for 2691 specified DTT device. 2692 2693 CONFIG_SOFT_I2C_READ_REPEATED_START 2694 2695 defining this will force the i2c_read() function in 2696 the soft_i2c driver to perform an I2C repeated start 2697 between writing the address pointer and reading the 2698 data. If this define is omitted the default behaviour 2699 of doing a stop-start sequence will be used. Most I2C 2700 devices can use either method, but some require one or 2701 the other. 2702 2703- SPI Support: CONFIG_SPI 2704 2705 Enables SPI driver (so far only tested with 2706 SPI EEPROM, also an instance works with Crystal A/D and 2707 D/As on the SACSng board) 2708 2709 CONFIG_SH_SPI 2710 2711 Enables the driver for SPI controller on SuperH. Currently 2712 only SH7757 is supported. 2713 2714 CONFIG_SPI_X 2715 2716 Enables extended (16-bit) SPI EEPROM addressing. 2717 (symmetrical to CONFIG_I2C_X) 2718 2719 CONFIG_SOFT_SPI 2720 2721 Enables a software (bit-bang) SPI driver rather than 2722 using hardware support. This is a general purpose 2723 driver that only requires three general I/O port pins 2724 (two outputs, one input) to function. If this is 2725 defined, the board configuration must define several 2726 SPI configuration items (port pins to use, etc). For 2727 an example, see include/configs/sacsng.h. 2728 2729 CONFIG_HARD_SPI 2730 2731 Enables a hardware SPI driver for general-purpose reads 2732 and writes. As with CONFIG_SOFT_SPI, the board configuration 2733 must define a list of chip-select function pointers. 2734 Currently supported on some MPC8xxx processors. For an 2735 example, see include/configs/mpc8349emds.h. 2736 2737 CONFIG_MXC_SPI 2738 2739 Enables the driver for the SPI controllers on i.MX and MXC 2740 SoCs. Currently i.MX31/35/51 are supported. 2741 2742 CONFIG_SYS_SPI_MXC_WAIT 2743 Timeout for waiting until spi transfer completed. 2744 default: (CONFIG_SYS_HZ/100) /* 10 ms */ 2745 2746- FPGA Support: CONFIG_FPGA 2747 2748 Enables FPGA subsystem. 2749 2750 CONFIG_FPGA_<vendor> 2751 2752 Enables support for specific chip vendors. 2753 (ALTERA, XILINX) 2754 2755 CONFIG_FPGA_<family> 2756 2757 Enables support for FPGA family. 2758 (SPARTAN2, SPARTAN3, VIRTEX2, CYCLONE2, ACEX1K, ACEX) 2759 2760 CONFIG_FPGA_COUNT 2761 2762 Specify the number of FPGA devices to support. 2763 2764 CONFIG_CMD_FPGA_LOADMK 2765 2766 Enable support for fpga loadmk command 2767 2768 CONFIG_CMD_FPGA_LOADP 2769 2770 Enable support for fpga loadp command - load partial bitstream 2771 2772 CONFIG_CMD_FPGA_LOADBP 2773 2774 Enable support for fpga loadbp command - load partial bitstream 2775 (Xilinx only) 2776 2777 CONFIG_SYS_FPGA_PROG_FEEDBACK 2778 2779 Enable printing of hash marks during FPGA configuration. 2780 2781 CONFIG_SYS_FPGA_CHECK_BUSY 2782 2783 Enable checks on FPGA configuration interface busy 2784 status by the configuration function. This option 2785 will require a board or device specific function to 2786 be written. 2787 2788 CONFIG_FPGA_DELAY 2789 2790 If defined, a function that provides delays in the FPGA 2791 configuration driver. 2792 2793 CONFIG_SYS_FPGA_CHECK_CTRLC 2794 Allow Control-C to interrupt FPGA configuration 2795 2796 CONFIG_SYS_FPGA_CHECK_ERROR 2797 2798 Check for configuration errors during FPGA bitfile 2799 loading. For example, abort during Virtex II 2800 configuration if the INIT_B line goes low (which 2801 indicated a CRC error). 2802 2803 CONFIG_SYS_FPGA_WAIT_INIT 2804 2805 Maximum time to wait for the INIT_B line to de-assert 2806 after PROB_B has been de-asserted during a Virtex II 2807 FPGA configuration sequence. The default time is 500 2808 ms. 2809 2810 CONFIG_SYS_FPGA_WAIT_BUSY 2811 2812 Maximum time to wait for BUSY to de-assert during 2813 Virtex II FPGA configuration. The default is 5 ms. 2814 2815 CONFIG_SYS_FPGA_WAIT_CONFIG 2816 2817 Time to wait after FPGA configuration. The default is 2818 200 ms. 2819 2820- Configuration Management: 2821 CONFIG_BUILD_TARGET 2822 2823 Some SoCs need special image types (e.g. U-Boot binary 2824 with a special header) as build targets. By defining 2825 CONFIG_BUILD_TARGET in the SoC / board header, this 2826 special image will be automatically built upon calling 2827 make / MAKEALL. 2828 2829 CONFIG_IDENT_STRING 2830 2831 If defined, this string will be added to the U-Boot 2832 version information (U_BOOT_VERSION) 2833 2834- Vendor Parameter Protection: 2835 2836 U-Boot considers the values of the environment 2837 variables "serial#" (Board Serial Number) and 2838 "ethaddr" (Ethernet Address) to be parameters that 2839 are set once by the board vendor / manufacturer, and 2840 protects these variables from casual modification by 2841 the user. Once set, these variables are read-only, 2842 and write or delete attempts are rejected. You can 2843 change this behaviour: 2844 2845 If CONFIG_ENV_OVERWRITE is #defined in your config 2846 file, the write protection for vendor parameters is 2847 completely disabled. Anybody can change or delete 2848 these parameters. 2849 2850 Alternatively, if you define _both_ an ethaddr in the 2851 default env _and_ CONFIG_OVERWRITE_ETHADDR_ONCE, a default 2852 Ethernet address is installed in the environment, 2853 which can be changed exactly ONCE by the user. [The 2854 serial# is unaffected by this, i. e. it remains 2855 read-only.] 2856 2857 The same can be accomplished in a more flexible way 2858 for any variable by configuring the type of access 2859 to allow for those variables in the ".flags" variable 2860 or define CONFIG_ENV_FLAGS_LIST_STATIC. 2861 2862- Protected RAM: 2863 CONFIG_PRAM 2864 2865 Define this variable to enable the reservation of 2866 "protected RAM", i. e. RAM which is not overwritten 2867 by U-Boot. Define CONFIG_PRAM to hold the number of 2868 kB you want to reserve for pRAM. You can overwrite 2869 this default value by defining an environment 2870 variable "pram" to the number of kB you want to 2871 reserve. Note that the board info structure will 2872 still show the full amount of RAM. If pRAM is 2873 reserved, a new environment variable "mem" will 2874 automatically be defined to hold the amount of 2875 remaining RAM in a form that can be passed as boot 2876 argument to Linux, for instance like that: 2877 2878 setenv bootargs ... mem=\${mem} 2879 saveenv 2880 2881 This way you can tell Linux not to use this memory, 2882 either, which results in a memory region that will 2883 not be affected by reboots. 2884 2885 *WARNING* If your board configuration uses automatic 2886 detection of the RAM size, you must make sure that 2887 this memory test is non-destructive. So far, the 2888 following board configurations are known to be 2889 "pRAM-clean": 2890 2891 IVMS8, IVML24, SPD8xx, TQM8xxL, 2892 HERMES, IP860, RPXlite, LWMON, 2893 FLAGADM, TQM8260 2894 2895- Access to physical memory region (> 4GB) 2896 Some basic support is provided for operations on memory not 2897 normally accessible to U-Boot - e.g. some architectures 2898 support access to more than 4GB of memory on 32-bit 2899 machines using physical address extension or similar. 2900 Define CONFIG_PHYSMEM to access this basic support, which 2901 currently only supports clearing the memory. 2902 2903- Error Recovery: 2904 CONFIG_PANIC_HANG 2905 2906 Define this variable to stop the system in case of a 2907 fatal error, so that you have to reset it manually. 2908 This is probably NOT a good idea for an embedded 2909 system where you want the system to reboot 2910 automatically as fast as possible, but it may be 2911 useful during development since you can try to debug 2912 the conditions that lead to the situation. 2913 2914 CONFIG_NET_RETRY_COUNT 2915 2916 This variable defines the number of retries for 2917 network operations like ARP, RARP, TFTP, or BOOTP 2918 before giving up the operation. If not defined, a 2919 default value of 5 is used. 2920 2921 CONFIG_ARP_TIMEOUT 2922 2923 Timeout waiting for an ARP reply in milliseconds. 2924 2925 CONFIG_NFS_TIMEOUT 2926 2927 Timeout in milliseconds used in NFS protocol. 2928 If you encounter "ERROR: Cannot umount" in nfs command, 2929 try longer timeout such as 2930 #define CONFIG_NFS_TIMEOUT 10000UL 2931 2932- Command Interpreter: 2933 CONFIG_AUTO_COMPLETE 2934 2935 Enable auto completion of commands using TAB. 2936 2937 CONFIG_SYS_PROMPT_HUSH_PS2 2938 2939 This defines the secondary prompt string, which is 2940 printed when the command interpreter needs more input 2941 to complete a command. Usually "> ". 2942 2943 Note: 2944 2945 In the current implementation, the local variables 2946 space and global environment variables space are 2947 separated. Local variables are those you define by 2948 simply typing `name=value'. To access a local 2949 variable later on, you have write `$name' or 2950 `${name}'; to execute the contents of a variable 2951 directly type `$name' at the command prompt. 2952 2953 Global environment variables are those you use 2954 setenv/printenv to work with. To run a command stored 2955 in such a variable, you need to use the run command, 2956 and you must not use the '$' sign to access them. 2957 2958 To store commands and special characters in a 2959 variable, please use double quotation marks 2960 surrounding the whole text of the variable, instead 2961 of the backslashes before semicolons and special 2962 symbols. 2963 2964- Command Line Editing and History: 2965 CONFIG_CMDLINE_EDITING 2966 2967 Enable editing and History functions for interactive 2968 command line input operations 2969 2970- Default Environment: 2971 CONFIG_EXTRA_ENV_SETTINGS 2972 2973 Define this to contain any number of null terminated 2974 strings (variable = value pairs) that will be part of 2975 the default environment compiled into the boot image. 2976 2977 For example, place something like this in your 2978 board's config file: 2979 2980 #define CONFIG_EXTRA_ENV_SETTINGS \ 2981 "myvar1=value1\0" \ 2982 "myvar2=value2\0" 2983 2984 Warning: This method is based on knowledge about the 2985 internal format how the environment is stored by the 2986 U-Boot code. This is NOT an official, exported 2987 interface! Although it is unlikely that this format 2988 will change soon, there is no guarantee either. 2989 You better know what you are doing here. 2990 2991 Note: overly (ab)use of the default environment is 2992 discouraged. Make sure to check other ways to preset 2993 the environment like the "source" command or the 2994 boot command first. 2995 2996 CONFIG_ENV_VARS_UBOOT_CONFIG 2997 2998 Define this in order to add variables describing the 2999 U-Boot build configuration to the default environment. 3000 These will be named arch, cpu, board, vendor, and soc. 3001 3002 Enabling this option will cause the following to be defined: 3003 3004 - CONFIG_SYS_ARCH 3005 - CONFIG_SYS_CPU 3006 - CONFIG_SYS_BOARD 3007 - CONFIG_SYS_VENDOR 3008 - CONFIG_SYS_SOC 3009 3010 CONFIG_ENV_VARS_UBOOT_RUNTIME_CONFIG 3011 3012 Define this in order to add variables describing certain 3013 run-time determined information about the hardware to the 3014 environment. These will be named board_name, board_rev. 3015 3016 CONFIG_DELAY_ENVIRONMENT 3017 3018 Normally the environment is loaded when the board is 3019 initialised so that it is available to U-Boot. This inhibits 3020 that so that the environment is not available until 3021 explicitly loaded later by U-Boot code. With CONFIG_OF_CONTROL 3022 this is instead controlled by the value of 3023 /config/load-environment. 3024 3025- Parallel Flash support: 3026 CONFIG_SYS_NO_FLASH 3027 3028 Traditionally U-boot was run on systems with parallel NOR 3029 flash. This option is used to disable support for parallel NOR 3030 flash. This option should be defined if the board does not have 3031 parallel flash. 3032 3033 If this option is not defined one of the generic flash drivers 3034 (e.g. CONFIG_FLASH_CFI_DRIVER or CONFIG_ST_SMI) must be 3035 selected or the board must provide an implementation of the 3036 flash API (see include/flash.h). 3037 3038- DataFlash Support: 3039 CONFIG_HAS_DATAFLASH 3040 3041 Defining this option enables DataFlash features and 3042 allows to read/write in Dataflash via the standard 3043 commands cp, md... 3044 3045- Serial Flash support 3046 CONFIG_CMD_SF 3047 3048 Defining this option enables SPI flash commands 3049 'sf probe/read/write/erase/update'. 3050 3051 Usage requires an initial 'probe' to define the serial 3052 flash parameters, followed by read/write/erase/update 3053 commands. 3054 3055 The following defaults may be provided by the platform 3056 to handle the common case when only a single serial 3057 flash is present on the system. 3058 3059 CONFIG_SF_DEFAULT_BUS Bus identifier 3060 CONFIG_SF_DEFAULT_CS Chip-select 3061 CONFIG_SF_DEFAULT_MODE (see include/spi.h) 3062 CONFIG_SF_DEFAULT_SPEED in Hz 3063 3064 CONFIG_CMD_SF_TEST 3065 3066 Define this option to include a destructive SPI flash 3067 test ('sf test'). 3068 3069 CONFIG_SF_DUAL_FLASH Dual flash memories 3070 3071 Define this option to use dual flash support where two flash 3072 memories can be connected with a given cs line. 3073 Currently Xilinx Zynq qspi supports these type of connections. 3074 3075- SystemACE Support: 3076 CONFIG_SYSTEMACE 3077 3078 Adding this option adds support for Xilinx SystemACE 3079 chips attached via some sort of local bus. The address 3080 of the chip must also be defined in the 3081 CONFIG_SYS_SYSTEMACE_BASE macro. For example: 3082 3083 #define CONFIG_SYSTEMACE 3084 #define CONFIG_SYS_SYSTEMACE_BASE 0xf0000000 3085 3086 When SystemACE support is added, the "ace" device type 3087 becomes available to the fat commands, i.e. fatls. 3088 3089- TFTP Fixed UDP Port: 3090 CONFIG_TFTP_PORT 3091 3092 If this is defined, the environment variable tftpsrcp 3093 is used to supply the TFTP UDP source port value. 3094 If tftpsrcp isn't defined, the normal pseudo-random port 3095 number generator is used. 3096 3097 Also, the environment variable tftpdstp is used to supply 3098 the TFTP UDP destination port value. If tftpdstp isn't 3099 defined, the normal port 69 is used. 3100 3101 The purpose for tftpsrcp is to allow a TFTP server to 3102 blindly start the TFTP transfer using the pre-configured 3103 target IP address and UDP port. This has the effect of 3104 "punching through" the (Windows XP) firewall, allowing 3105 the remainder of the TFTP transfer to proceed normally. 3106 A better solution is to properly configure the firewall, 3107 but sometimes that is not allowed. 3108 3109- Hashing support: 3110 CONFIG_CMD_HASH 3111 3112 This enables a generic 'hash' command which can produce 3113 hashes / digests from a few algorithms (e.g. SHA1, SHA256). 3114 3115 CONFIG_HASH_VERIFY 3116 3117 Enable the hash verify command (hash -v). This adds to code 3118 size a little. 3119 3120 CONFIG_SHA1 - This option enables support of hashing using SHA1 3121 algorithm. The hash is calculated in software. 3122 CONFIG_SHA256 - This option enables support of hashing using 3123 SHA256 algorithm. The hash is calculated in software. 3124 CONFIG_SHA_HW_ACCEL - This option enables hardware acceleration 3125 for SHA1/SHA256 hashing. 3126 This affects the 'hash' command and also the 3127 hash_lookup_algo() function. 3128 CONFIG_SHA_PROG_HW_ACCEL - This option enables 3129 hardware-acceleration for SHA1/SHA256 progressive hashing. 3130 Data can be streamed in a block at a time and the hashing 3131 is performed in hardware. 3132 3133 Note: There is also a sha1sum command, which should perhaps 3134 be deprecated in favour of 'hash sha1'. 3135 3136- Freescale i.MX specific commands: 3137 CONFIG_CMD_HDMIDETECT 3138 This enables 'hdmidet' command which returns true if an 3139 HDMI monitor is detected. This command is i.MX 6 specific. 3140 3141 CONFIG_CMD_BMODE 3142 This enables the 'bmode' (bootmode) command for forcing 3143 a boot from specific media. 3144 3145 This is useful for forcing the ROM's usb downloader to 3146 activate upon a watchdog reset which is nice when iterating 3147 on U-Boot. Using the reset button or running bmode normal 3148 will set it back to normal. This command currently 3149 supports i.MX53 and i.MX6. 3150 3151- Signing support: 3152 CONFIG_RSA 3153 3154 This enables the RSA algorithm used for FIT image verification 3155 in U-Boot. See doc/uImage.FIT/signature.txt for more information. 3156 3157 The Modular Exponentiation algorithm in RSA is implemented using 3158 driver model. So CONFIG_DM needs to be enabled by default for this 3159 library to function. 3160 3161 The signing part is build into mkimage regardless of this 3162 option. The software based modular exponentiation is built into 3163 mkimage irrespective of this option. 3164 3165- bootcount support: 3166 CONFIG_BOOTCOUNT_LIMIT 3167 3168 This enables the bootcounter support, see: 3169 http://www.denx.de/wiki/DULG/UBootBootCountLimit 3170 3171 CONFIG_AT91SAM9XE 3172 enable special bootcounter support on at91sam9xe based boards. 3173 CONFIG_BLACKFIN 3174 enable special bootcounter support on blackfin based boards. 3175 CONFIG_SOC_DA8XX 3176 enable special bootcounter support on da850 based boards. 3177 CONFIG_BOOTCOUNT_RAM 3178 enable support for the bootcounter in RAM 3179 CONFIG_BOOTCOUNT_I2C 3180 enable support for the bootcounter on an i2c (like RTC) device. 3181 CONFIG_SYS_I2C_RTC_ADDR = i2c chip address 3182 CONFIG_SYS_BOOTCOUNT_ADDR = i2c addr which is used for 3183 the bootcounter. 3184 CONFIG_BOOTCOUNT_ALEN = address len 3185 3186- Show boot progress: 3187 CONFIG_SHOW_BOOT_PROGRESS 3188 3189 Defining this option allows to add some board- 3190 specific code (calling a user-provided function 3191 "show_boot_progress(int)") that enables you to show 3192 the system's boot progress on some display (for 3193 example, some LED's) on your board. At the moment, 3194 the following checkpoints are implemented: 3195 3196 3197Legacy uImage format: 3198 3199 Arg Where When 3200 1 common/cmd_bootm.c before attempting to boot an image 3201 -1 common/cmd_bootm.c Image header has bad magic number 3202 2 common/cmd_bootm.c Image header has correct magic number 3203 -2 common/cmd_bootm.c Image header has bad checksum 3204 3 common/cmd_bootm.c Image header has correct checksum 3205 -3 common/cmd_bootm.c Image data has bad checksum 3206 4 common/cmd_bootm.c Image data has correct checksum 3207 -4 common/cmd_bootm.c Image is for unsupported architecture 3208 5 common/cmd_bootm.c Architecture check OK 3209 -5 common/cmd_bootm.c Wrong Image Type (not kernel, multi) 3210 6 common/cmd_bootm.c Image Type check OK 3211 -6 common/cmd_bootm.c gunzip uncompression error 3212 -7 common/cmd_bootm.c Unimplemented compression type 3213 7 common/cmd_bootm.c Uncompression OK 3214 8 common/cmd_bootm.c No uncompress/copy overwrite error 3215 -9 common/cmd_bootm.c Unsupported OS (not Linux, BSD, VxWorks, QNX) 3216 3217 9 common/image.c Start initial ramdisk verification 3218 -10 common/image.c Ramdisk header has bad magic number 3219 -11 common/image.c Ramdisk header has bad checksum 3220 10 common/image.c Ramdisk header is OK 3221 -12 common/image.c Ramdisk data has bad checksum 3222 11 common/image.c Ramdisk data has correct checksum 3223 12 common/image.c Ramdisk verification complete, start loading 3224 -13 common/image.c Wrong Image Type (not PPC Linux ramdisk) 3225 13 common/image.c Start multifile image verification 3226 14 common/image.c No initial ramdisk, no multifile, continue. 3227 3228 15 arch/<arch>/lib/bootm.c All preparation done, transferring control to OS 3229 3230 -30 arch/powerpc/lib/board.c Fatal error, hang the system 3231 -31 post/post.c POST test failed, detected by post_output_backlog() 3232 -32 post/post.c POST test failed, detected by post_run_single() 3233 3234 34 common/cmd_doc.c before loading a Image from a DOC device 3235 -35 common/cmd_doc.c Bad usage of "doc" command 3236 35 common/cmd_doc.c correct usage of "doc" command 3237 -36 common/cmd_doc.c No boot device 3238 36 common/cmd_doc.c correct boot device 3239 -37 common/cmd_doc.c Unknown Chip ID on boot device 3240 37 common/cmd_doc.c correct chip ID found, device available 3241 -38 common/cmd_doc.c Read Error on boot device 3242 38 common/cmd_doc.c reading Image header from DOC device OK 3243 -39 common/cmd_doc.c Image header has bad magic number 3244 39 common/cmd_doc.c Image header has correct magic number 3245 -40 common/cmd_doc.c Error reading Image from DOC device 3246 40 common/cmd_doc.c Image header has correct magic number 3247 41 common/cmd_ide.c before loading a Image from a IDE device 3248 -42 common/cmd_ide.c Bad usage of "ide" command 3249 42 common/cmd_ide.c correct usage of "ide" command 3250 -43 common/cmd_ide.c No boot device 3251 43 common/cmd_ide.c boot device found 3252 -44 common/cmd_ide.c Device not available 3253 44 common/cmd_ide.c Device available 3254 -45 common/cmd_ide.c wrong partition selected 3255 45 common/cmd_ide.c partition selected 3256 -46 common/cmd_ide.c Unknown partition table 3257 46 common/cmd_ide.c valid partition table found 3258 -47 common/cmd_ide.c Invalid partition type 3259 47 common/cmd_ide.c correct partition type 3260 -48 common/cmd_ide.c Error reading Image Header on boot device 3261 48 common/cmd_ide.c reading Image Header from IDE device OK 3262 -49 common/cmd_ide.c Image header has bad magic number 3263 49 common/cmd_ide.c Image header has correct magic number 3264 -50 common/cmd_ide.c Image header has bad checksum 3265 50 common/cmd_ide.c Image header has correct checksum 3266 -51 common/cmd_ide.c Error reading Image from IDE device 3267 51 common/cmd_ide.c reading Image from IDE device OK 3268 52 common/cmd_nand.c before loading a Image from a NAND device 3269 -53 common/cmd_nand.c Bad usage of "nand" command 3270 53 common/cmd_nand.c correct usage of "nand" command 3271 -54 common/cmd_nand.c No boot device 3272 54 common/cmd_nand.c boot device found 3273 -55 common/cmd_nand.c Unknown Chip ID on boot device 3274 55 common/cmd_nand.c correct chip ID found, device available 3275 -56 common/cmd_nand.c Error reading Image Header on boot device 3276 56 common/cmd_nand.c reading Image Header from NAND device OK 3277 -57 common/cmd_nand.c Image header has bad magic number 3278 57 common/cmd_nand.c Image header has correct magic number 3279 -58 common/cmd_nand.c Error reading Image from NAND device 3280 58 common/cmd_nand.c reading Image from NAND device OK 3281 3282 -60 common/env_common.c Environment has a bad CRC, using default 3283 3284 64 net/eth.c starting with Ethernet configuration. 3285 -64 net/eth.c no Ethernet found. 3286 65 net/eth.c Ethernet found. 3287 3288 -80 common/cmd_net.c usage wrong 3289 80 common/cmd_net.c before calling net_loop() 3290 -81 common/cmd_net.c some error in net_loop() occurred 3291 81 common/cmd_net.c net_loop() back without error 3292 -82 common/cmd_net.c size == 0 (File with size 0 loaded) 3293 82 common/cmd_net.c trying automatic boot 3294 83 common/cmd_net.c running "source" command 3295 -83 common/cmd_net.c some error in automatic boot or "source" command 3296 84 common/cmd_net.c end without errors 3297 3298FIT uImage format: 3299 3300 Arg Where When 3301 100 common/cmd_bootm.c Kernel FIT Image has correct format 3302 -100 common/cmd_bootm.c Kernel FIT Image has incorrect format 3303 101 common/cmd_bootm.c No Kernel subimage unit name, using configuration 3304 -101 common/cmd_bootm.c Can't get configuration for kernel subimage 3305 102 common/cmd_bootm.c Kernel unit name specified 3306 -103 common/cmd_bootm.c Can't get kernel subimage node offset 3307 103 common/cmd_bootm.c Found configuration node 3308 104 common/cmd_bootm.c Got kernel subimage node offset 3309 -104 common/cmd_bootm.c Kernel subimage hash verification failed 3310 105 common/cmd_bootm.c Kernel subimage hash verification OK 3311 -105 common/cmd_bootm.c Kernel subimage is for unsupported architecture 3312 106 common/cmd_bootm.c Architecture check OK 3313 -106 common/cmd_bootm.c Kernel subimage has wrong type 3314 107 common/cmd_bootm.c Kernel subimage type OK 3315 -107 common/cmd_bootm.c Can't get kernel subimage data/size 3316 108 common/cmd_bootm.c Got kernel subimage data/size 3317 -108 common/cmd_bootm.c Wrong image type (not legacy, FIT) 3318 -109 common/cmd_bootm.c Can't get kernel subimage type 3319 -110 common/cmd_bootm.c Can't get kernel subimage comp 3320 -111 common/cmd_bootm.c Can't get kernel subimage os 3321 -112 common/cmd_bootm.c Can't get kernel subimage load address 3322 -113 common/cmd_bootm.c Image uncompress/copy overwrite error 3323 3324 120 common/image.c Start initial ramdisk verification 3325 -120 common/image.c Ramdisk FIT image has incorrect format 3326 121 common/image.c Ramdisk FIT image has correct format 3327 122 common/image.c No ramdisk subimage unit name, using configuration 3328 -122 common/image.c Can't get configuration for ramdisk subimage 3329 123 common/image.c Ramdisk unit name specified 3330 -124 common/image.c Can't get ramdisk subimage node offset 3331 125 common/image.c Got ramdisk subimage node offset 3332 -125 common/image.c Ramdisk subimage hash verification failed 3333 126 common/image.c Ramdisk subimage hash verification OK 3334 -126 common/image.c Ramdisk subimage for unsupported architecture 3335 127 common/image.c Architecture check OK 3336 -127 common/image.c Can't get ramdisk subimage data/size 3337 128 common/image.c Got ramdisk subimage data/size 3338 129 common/image.c Can't get ramdisk load address 3339 -129 common/image.c Got ramdisk load address 3340 3341 -130 common/cmd_doc.c Incorrect FIT image format 3342 131 common/cmd_doc.c FIT image format OK 3343 3344 -140 common/cmd_ide.c Incorrect FIT image format 3345 141 common/cmd_ide.c FIT image format OK 3346 3347 -150 common/cmd_nand.c Incorrect FIT image format 3348 151 common/cmd_nand.c FIT image format OK 3349 3350- legacy image format: 3351 CONFIG_IMAGE_FORMAT_LEGACY 3352 enables the legacy image format support in U-Boot. 3353 3354 Default: 3355 enabled if CONFIG_FIT_SIGNATURE is not defined. 3356 3357 CONFIG_DISABLE_IMAGE_LEGACY 3358 disable the legacy image format 3359 3360 This define is introduced, as the legacy image format is 3361 enabled per default for backward compatibility. 3362 3363- FIT image support: 3364 CONFIG_FIT 3365 Enable support for the FIT uImage format. 3366 3367 CONFIG_FIT_BEST_MATCH 3368 When no configuration is explicitly selected, default to the 3369 one whose fdt's compatibility field best matches that of 3370 U-Boot itself. A match is considered "best" if it matches the 3371 most specific compatibility entry of U-Boot's fdt's root node. 3372 The order of entries in the configuration's fdt is ignored. 3373 3374 CONFIG_FIT_SIGNATURE 3375 This option enables signature verification of FIT uImages, 3376 using a hash signed and verified using RSA. If 3377 CONFIG_SHA_PROG_HW_ACCEL is defined, i.e support for progressive 3378 hashing is available using hardware, RSA library will use it. 3379 See doc/uImage.FIT/signature.txt for more details. 3380 3381 WARNING: When relying on signed FIT images with required 3382 signature check the legacy image format is default 3383 disabled. If a board need legacy image format support 3384 enable this through CONFIG_IMAGE_FORMAT_LEGACY 3385 3386 CONFIG_FIT_DISABLE_SHA256 3387 Supporting SHA256 hashes has quite an impact on binary size. 3388 For constrained systems sha256 hash support can be disabled 3389 with this option. 3390 3391- Standalone program support: 3392 CONFIG_STANDALONE_LOAD_ADDR 3393 3394 This option defines a board specific value for the 3395 address where standalone program gets loaded, thus 3396 overwriting the architecture dependent default 3397 settings. 3398 3399- Frame Buffer Address: 3400 CONFIG_FB_ADDR 3401 3402 Define CONFIG_FB_ADDR if you want to use specific 3403 address for frame buffer. This is typically the case 3404 when using a graphics controller has separate video 3405 memory. U-Boot will then place the frame buffer at 3406 the given address instead of dynamically reserving it 3407 in system RAM by calling lcd_setmem(), which grabs 3408 the memory for the frame buffer depending on the 3409 configured panel size. 3410 3411 Please see board_init_f function. 3412 3413- Automatic software updates via TFTP server 3414 CONFIG_UPDATE_TFTP 3415 CONFIG_UPDATE_TFTP_CNT_MAX 3416 CONFIG_UPDATE_TFTP_MSEC_MAX 3417 3418 These options enable and control the auto-update feature; 3419 for a more detailed description refer to doc/README.update. 3420 3421- MTD Support (mtdparts command, UBI support) 3422 CONFIG_MTD_DEVICE 3423 3424 Adds the MTD device infrastructure from the Linux kernel. 3425 Needed for mtdparts command support. 3426 3427 CONFIG_MTD_PARTITIONS 3428 3429 Adds the MTD partitioning infrastructure from the Linux 3430 kernel. Needed for UBI support. 3431 3432- UBI support 3433 CONFIG_CMD_UBI 3434 3435 Adds commands for interacting with MTD partitions formatted 3436 with the UBI flash translation layer 3437 3438 Requires also defining CONFIG_RBTREE 3439 3440 CONFIG_UBI_SILENCE_MSG 3441 3442 Make the verbose messages from UBI stop printing. This leaves 3443 warnings and errors enabled. 3444 3445 3446 CONFIG_MTD_UBI_WL_THRESHOLD 3447 This parameter defines the maximum difference between the highest 3448 erase counter value and the lowest erase counter value of eraseblocks 3449 of UBI devices. When this threshold is exceeded, UBI starts performing 3450 wear leveling by means of moving data from eraseblock with low erase 3451 counter to eraseblocks with high erase counter. 3452 3453 The default value should be OK for SLC NAND flashes, NOR flashes and 3454 other flashes which have eraseblock life-cycle 100000 or more. 3455 However, in case of MLC NAND flashes which typically have eraseblock 3456 life-cycle less than 10000, the threshold should be lessened (e.g., 3457 to 128 or 256, although it does not have to be power of 2). 3458 3459 default: 4096 3460 3461 CONFIG_MTD_UBI_BEB_LIMIT 3462 This option specifies the maximum bad physical eraseblocks UBI 3463 expects on the MTD device (per 1024 eraseblocks). If the 3464 underlying flash does not admit of bad eraseblocks (e.g. NOR 3465 flash), this value is ignored. 3466 3467 NAND datasheets often specify the minimum and maximum NVM 3468 (Number of Valid Blocks) for the flashes' endurance lifetime. 3469 The maximum expected bad eraseblocks per 1024 eraseblocks 3470 then can be calculated as "1024 * (1 - MinNVB / MaxNVB)", 3471 which gives 20 for most NANDs (MaxNVB is basically the total 3472 count of eraseblocks on the chip). 3473 3474 To put it differently, if this value is 20, UBI will try to 3475 reserve about 1.9% of physical eraseblocks for bad blocks 3476 handling. And that will be 1.9% of eraseblocks on the entire 3477 NAND chip, not just the MTD partition UBI attaches. This means 3478 that if you have, say, a NAND flash chip admits maximum 40 bad 3479 eraseblocks, and it is split on two MTD partitions of the same 3480 size, UBI will reserve 40 eraseblocks when attaching a 3481 partition. 3482 3483 default: 20 3484 3485 CONFIG_MTD_UBI_FASTMAP 3486 Fastmap is a mechanism which allows attaching an UBI device 3487 in nearly constant time. Instead of scanning the whole MTD device it 3488 only has to locate a checkpoint (called fastmap) on the device. 3489 The on-flash fastmap contains all information needed to attach 3490 the device. Using fastmap makes only sense on large devices where 3491 attaching by scanning takes long. UBI will not automatically install 3492 a fastmap on old images, but you can set the UBI parameter 3493 CONFIG_MTD_UBI_FASTMAP_AUTOCONVERT to 1 if you want so. Please note 3494 that fastmap-enabled images are still usable with UBI implementations 3495 without fastmap support. On typical flash devices the whole fastmap 3496 fits into one PEB. UBI will reserve PEBs to hold two fastmaps. 3497 3498 CONFIG_MTD_UBI_FASTMAP_AUTOCONVERT 3499 Set this parameter to enable fastmap automatically on images 3500 without a fastmap. 3501 default: 0 3502 3503- UBIFS support 3504 CONFIG_CMD_UBIFS 3505 3506 Adds commands for interacting with UBI volumes formatted as 3507 UBIFS. UBIFS is read-only in u-boot. 3508 3509 Requires UBI support as well as CONFIG_LZO 3510 3511 CONFIG_UBIFS_SILENCE_MSG 3512 3513 Make the verbose messages from UBIFS stop printing. This leaves 3514 warnings and errors enabled. 3515 3516- SPL framework 3517 CONFIG_SPL 3518 Enable building of SPL globally. 3519 3520 CONFIG_SPL_LDSCRIPT 3521 LDSCRIPT for linking the SPL binary. 3522 3523 CONFIG_SPL_MAX_FOOTPRINT 3524 Maximum size in memory allocated to the SPL, BSS included. 3525 When defined, the linker checks that the actual memory 3526 used by SPL from _start to __bss_end does not exceed it. 3527 CONFIG_SPL_MAX_FOOTPRINT and CONFIG_SPL_BSS_MAX_SIZE 3528 must not be both defined at the same time. 3529 3530 CONFIG_SPL_MAX_SIZE 3531 Maximum size of the SPL image (text, data, rodata, and 3532 linker lists sections), BSS excluded. 3533 When defined, the linker checks that the actual size does 3534 not exceed it. 3535 3536 CONFIG_SPL_TEXT_BASE 3537 TEXT_BASE for linking the SPL binary. 3538 3539 CONFIG_SPL_RELOC_TEXT_BASE 3540 Address to relocate to. If unspecified, this is equal to 3541 CONFIG_SPL_TEXT_BASE (i.e. no relocation is done). 3542 3543 CONFIG_SPL_BSS_START_ADDR 3544 Link address for the BSS within the SPL binary. 3545 3546 CONFIG_SPL_BSS_MAX_SIZE 3547 Maximum size in memory allocated to the SPL BSS. 3548 When defined, the linker checks that the actual memory used 3549 by SPL from __bss_start to __bss_end does not exceed it. 3550 CONFIG_SPL_MAX_FOOTPRINT and CONFIG_SPL_BSS_MAX_SIZE 3551 must not be both defined at the same time. 3552 3553 CONFIG_SPL_STACK 3554 Adress of the start of the stack SPL will use 3555 3556 CONFIG_SPL_PANIC_ON_RAW_IMAGE 3557 When defined, SPL will panic() if the image it has 3558 loaded does not have a signature. 3559 Defining this is useful when code which loads images 3560 in SPL cannot guarantee that absolutely all read errors 3561 will be caught. 3562 An example is the LPC32XX MLC NAND driver, which will 3563 consider that a completely unreadable NAND block is bad, 3564 and thus should be skipped silently. 3565 3566 CONFIG_SPL_RELOC_STACK 3567 Adress of the start of the stack SPL will use after 3568 relocation. If unspecified, this is equal to 3569 CONFIG_SPL_STACK. 3570 3571 CONFIG_SYS_SPL_MALLOC_START 3572 Starting address of the malloc pool used in SPL. 3573 3574 CONFIG_SYS_SPL_MALLOC_SIZE 3575 The size of the malloc pool used in SPL. 3576 3577 CONFIG_SPL_FRAMEWORK 3578 Enable the SPL framework under common/. This framework 3579 supports MMC, NAND and YMODEM loading of U-Boot and NAND 3580 NAND loading of the Linux Kernel. 3581 3582 CONFIG_SPL_OS_BOOT 3583 Enable booting directly to an OS from SPL. 3584 See also: doc/README.falcon 3585 3586 CONFIG_SPL_DISPLAY_PRINT 3587 For ARM, enable an optional function to print more information 3588 about the running system. 3589 3590 CONFIG_SPL_INIT_MINIMAL 3591 Arch init code should be built for a very small image 3592 3593 CONFIG_SPL_LIBCOMMON_SUPPORT 3594 Support for common/libcommon.o in SPL binary 3595 3596 CONFIG_SPL_LIBDISK_SUPPORT 3597 Support for disk/libdisk.o in SPL binary 3598 3599 CONFIG_SPL_I2C_SUPPORT 3600 Support for drivers/i2c/libi2c.o in SPL binary 3601 3602 CONFIG_SPL_GPIO_SUPPORT 3603 Support for drivers/gpio/libgpio.o in SPL binary 3604 3605 CONFIG_SPL_MMC_SUPPORT 3606 Support for drivers/mmc/libmmc.o in SPL binary 3607 3608 CONFIG_SYS_MMCSD_RAW_MODE_U_BOOT_SECTOR, 3609 CONFIG_SYS_U_BOOT_MAX_SIZE_SECTORS, 3610 Address and partition on the MMC to load U-Boot from 3611 when the MMC is being used in raw mode. 3612 3613 CONFIG_SYS_MMCSD_RAW_MODE_U_BOOT_PARTITION 3614 Partition on the MMC to load U-Boot from when the MMC is being 3615 used in raw mode 3616 3617 CONFIG_SYS_MMCSD_RAW_MODE_KERNEL_SECTOR 3618 Sector to load kernel uImage from when MMC is being 3619 used in raw mode (for Falcon mode) 3620 3621 CONFIG_SYS_MMCSD_RAW_MODE_ARGS_SECTOR, 3622 CONFIG_SYS_MMCSD_RAW_MODE_ARGS_SECTORS 3623 Sector and number of sectors to load kernel argument 3624 parameters from when MMC is being used in raw mode 3625 (for falcon mode) 3626 3627 CONFIG_SYS_MMCSD_FS_BOOT_PARTITION 3628 Partition on the MMC to load U-Boot from when the MMC is being 3629 used in fs mode 3630 3631 CONFIG_SPL_FAT_SUPPORT 3632 Support for fs/fat/libfat.o in SPL binary 3633 3634 CONFIG_SPL_EXT_SUPPORT 3635 Support for EXT filesystem in SPL binary 3636 3637 CONFIG_SPL_FS_LOAD_PAYLOAD_NAME 3638 Filename to read to load U-Boot when reading from filesystem 3639 3640 CONFIG_SPL_FS_LOAD_KERNEL_NAME 3641 Filename to read to load kernel uImage when reading 3642 from filesystem (for Falcon mode) 3643 3644 CONFIG_SPL_FS_LOAD_ARGS_NAME 3645 Filename to read to load kernel argument parameters 3646 when reading from filesystem (for Falcon mode) 3647 3648 CONFIG_SPL_MPC83XX_WAIT_FOR_NAND 3649 Set this for NAND SPL on PPC mpc83xx targets, so that 3650 start.S waits for the rest of the SPL to load before 3651 continuing (the hardware starts execution after just 3652 loading the first page rather than the full 4K). 3653 3654 CONFIG_SPL_SKIP_RELOCATE 3655 Avoid SPL relocation 3656 3657 CONFIG_SPL_NAND_BASE 3658 Include nand_base.c in the SPL. Requires 3659 CONFIG_SPL_NAND_DRIVERS. 3660 3661 CONFIG_SPL_NAND_DRIVERS 3662 SPL uses normal NAND drivers, not minimal drivers. 3663 3664 CONFIG_SPL_NAND_ECC 3665 Include standard software ECC in the SPL 3666 3667 CONFIG_SPL_NAND_SIMPLE 3668 Support for NAND boot using simple NAND drivers that 3669 expose the cmd_ctrl() interface. 3670 3671 CONFIG_SPL_MTD_SUPPORT 3672 Support for the MTD subsystem within SPL. Useful for 3673 environment on NAND support within SPL. 3674 3675 CONFIG_SPL_NAND_RAW_ONLY 3676 Support to boot only raw u-boot.bin images. Use this only 3677 if you need to save space. 3678 3679 CONFIG_SPL_MPC8XXX_INIT_DDR_SUPPORT 3680 Set for the SPL on PPC mpc8xxx targets, support for 3681 drivers/ddr/fsl/libddr.o in SPL binary. 3682 3683 CONFIG_SPL_COMMON_INIT_DDR 3684 Set for common ddr init with serial presence detect in 3685 SPL binary. 3686 3687 CONFIG_SYS_NAND_5_ADDR_CYCLE, CONFIG_SYS_NAND_PAGE_COUNT, 3688 CONFIG_SYS_NAND_PAGE_SIZE, CONFIG_SYS_NAND_OOBSIZE, 3689 CONFIG_SYS_NAND_BLOCK_SIZE, CONFIG_SYS_NAND_BAD_BLOCK_POS, 3690 CONFIG_SYS_NAND_ECCPOS, CONFIG_SYS_NAND_ECCSIZE, 3691 CONFIG_SYS_NAND_ECCBYTES 3692 Defines the size and behavior of the NAND that SPL uses 3693 to read U-Boot 3694 3695 CONFIG_SPL_NAND_BOOT 3696 Add support NAND boot 3697 3698 CONFIG_SYS_NAND_U_BOOT_OFFS 3699 Location in NAND to read U-Boot from 3700 3701 CONFIG_SYS_NAND_U_BOOT_DST 3702 Location in memory to load U-Boot to 3703 3704 CONFIG_SYS_NAND_U_BOOT_SIZE 3705 Size of image to load 3706 3707 CONFIG_SYS_NAND_U_BOOT_START 3708 Entry point in loaded image to jump to 3709 3710 CONFIG_SYS_NAND_HW_ECC_OOBFIRST 3711 Define this if you need to first read the OOB and then the 3712 data. This is used, for example, on davinci platforms. 3713 3714 CONFIG_SPL_OMAP3_ID_NAND 3715 Support for an OMAP3-specific set of functions to return the 3716 ID and MFR of the first attached NAND chip, if present. 3717 3718 CONFIG_SPL_SERIAL_SUPPORT 3719 Support for drivers/serial/libserial.o in SPL binary 3720 3721 CONFIG_SPL_SPI_FLASH_SUPPORT 3722 Support for drivers/mtd/spi/libspi_flash.o in SPL binary 3723 3724 CONFIG_SPL_SPI_SUPPORT 3725 Support for drivers/spi/libspi.o in SPL binary 3726 3727 CONFIG_SPL_RAM_DEVICE 3728 Support for running image already present in ram, in SPL binary 3729 3730 CONFIG_SPL_LIBGENERIC_SUPPORT 3731 Support for lib/libgeneric.o in SPL binary 3732 3733 CONFIG_SPL_ENV_SUPPORT 3734 Support for the environment operating in SPL binary 3735 3736 CONFIG_SPL_NET_SUPPORT 3737 Support for the net/libnet.o in SPL binary. 3738 It conflicts with SPL env from storage medium specified by 3739 CONFIG_ENV_IS_xxx but CONFIG_ENV_IS_NOWHERE 3740 3741 CONFIG_SPL_PAD_TO 3742 Image offset to which the SPL should be padded before appending 3743 the SPL payload. By default, this is defined as 3744 CONFIG_SPL_MAX_SIZE, or 0 if CONFIG_SPL_MAX_SIZE is undefined. 3745 CONFIG_SPL_PAD_TO must be either 0, meaning to append the SPL 3746 payload without any padding, or >= CONFIG_SPL_MAX_SIZE. 3747 3748 CONFIG_SPL_TARGET 3749 Final target image containing SPL and payload. Some SPLs 3750 use an arch-specific makefile fragment instead, for 3751 example if more than one image needs to be produced. 3752 3753 CONFIG_FIT_SPL_PRINT 3754 Printing information about a FIT image adds quite a bit of 3755 code to SPL. So this is normally disabled in SPL. Use this 3756 option to re-enable it. This will affect the output of the 3757 bootm command when booting a FIT image. 3758 3759- TPL framework 3760 CONFIG_TPL 3761 Enable building of TPL globally. 3762 3763 CONFIG_TPL_PAD_TO 3764 Image offset to which the TPL should be padded before appending 3765 the TPL payload. By default, this is defined as 3766 CONFIG_SPL_MAX_SIZE, or 0 if CONFIG_SPL_MAX_SIZE is undefined. 3767 CONFIG_SPL_PAD_TO must be either 0, meaning to append the SPL 3768 payload without any padding, or >= CONFIG_SPL_MAX_SIZE. 3769 3770Modem Support: 3771-------------- 3772 3773[so far only for SMDK2400 boards] 3774 3775- Modem support enable: 3776 CONFIG_MODEM_SUPPORT 3777 3778- RTS/CTS Flow control enable: 3779 CONFIG_HWFLOW 3780 3781- Modem debug support: 3782 CONFIG_MODEM_SUPPORT_DEBUG 3783 3784 Enables debugging stuff (char screen[1024], dbg()) 3785 for modem support. Useful only with BDI2000. 3786 3787- Interrupt support (PPC): 3788 3789 There are common interrupt_init() and timer_interrupt() 3790 for all PPC archs. interrupt_init() calls interrupt_init_cpu() 3791 for CPU specific initialization. interrupt_init_cpu() 3792 should set decrementer_count to appropriate value. If 3793 CPU resets decrementer automatically after interrupt 3794 (ppc4xx) it should set decrementer_count to zero. 3795 timer_interrupt() calls timer_interrupt_cpu() for CPU 3796 specific handling. If board has watchdog / status_led 3797 / other_activity_monitor it works automatically from 3798 general timer_interrupt(). 3799 3800- General: 3801 3802 In the target system modem support is enabled when a 3803 specific key (key combination) is pressed during 3804 power-on. Otherwise U-Boot will boot normally 3805 (autoboot). The key_pressed() function is called from 3806 board_init(). Currently key_pressed() is a dummy 3807 function, returning 1 and thus enabling modem 3808 initialization. 3809 3810 If there are no modem init strings in the 3811 environment, U-Boot proceed to autoboot; the 3812 previous output (banner, info printfs) will be 3813 suppressed, though. 3814 3815 See also: doc/README.Modem 3816 3817Board initialization settings: 3818------------------------------ 3819 3820During Initialization u-boot calls a number of board specific functions 3821to allow the preparation of board specific prerequisites, e.g. pin setup 3822before drivers are initialized. To enable these callbacks the 3823following configuration macros have to be defined. Currently this is 3824architecture specific, so please check arch/your_architecture/lib/board.c 3825typically in board_init_f() and board_init_r(). 3826 3827- CONFIG_BOARD_EARLY_INIT_F: Call board_early_init_f() 3828- CONFIG_BOARD_EARLY_INIT_R: Call board_early_init_r() 3829- CONFIG_BOARD_LATE_INIT: Call board_late_init() 3830- CONFIG_BOARD_POSTCLK_INIT: Call board_postclk_init() 3831 3832Configuration Settings: 3833----------------------- 3834 3835- CONFIG_SYS_SUPPORT_64BIT_DATA: Defined automatically if compiled as 64-bit. 3836 Optionally it can be defined to support 64-bit memory commands. 3837 3838- CONFIG_SYS_LONGHELP: Defined when you want long help messages included; 3839 undefine this when you're short of memory. 3840 3841- CONFIG_SYS_HELP_CMD_WIDTH: Defined when you want to override the default 3842 width of the commands listed in the 'help' command output. 3843 3844- CONFIG_SYS_PROMPT: This is what U-Boot prints on the console to 3845 prompt for user input. 3846 3847- CONFIG_SYS_CBSIZE: Buffer size for input from the Console 3848 3849- CONFIG_SYS_PBSIZE: Buffer size for Console output 3850 3851- CONFIG_SYS_MAXARGS: max. Number of arguments accepted for monitor commands 3852 3853- CONFIG_SYS_BARGSIZE: Buffer size for Boot Arguments which are passed to 3854 the application (usually a Linux kernel) when it is 3855 booted 3856 3857- CONFIG_SYS_BAUDRATE_TABLE: 3858 List of legal baudrate settings for this board. 3859 3860- CONFIG_SYS_CONSOLE_INFO_QUIET 3861 Suppress display of console information at boot. 3862 3863- CONFIG_SYS_CONSOLE_IS_IN_ENV 3864 If the board specific function 3865 extern int overwrite_console (void); 3866 returns 1, the stdin, stderr and stdout are switched to the 3867 serial port, else the settings in the environment are used. 3868 3869- CONFIG_SYS_CONSOLE_OVERWRITE_ROUTINE 3870 Enable the call to overwrite_console(). 3871 3872- CONFIG_SYS_CONSOLE_ENV_OVERWRITE 3873 Enable overwrite of previous console environment settings. 3874 3875- CONFIG_SYS_MEMTEST_START, CONFIG_SYS_MEMTEST_END: 3876 Begin and End addresses of the area used by the 3877 simple memory test. 3878 3879- CONFIG_SYS_ALT_MEMTEST: 3880 Enable an alternate, more extensive memory test. 3881 3882- CONFIG_SYS_MEMTEST_SCRATCH: 3883 Scratch address used by the alternate memory test 3884 You only need to set this if address zero isn't writeable 3885 3886- CONFIG_SYS_MEM_TOP_HIDE (PPC only): 3887 If CONFIG_SYS_MEM_TOP_HIDE is defined in the board config header, 3888 this specified memory area will get subtracted from the top 3889 (end) of RAM and won't get "touched" at all by U-Boot. By 3890 fixing up gd->ram_size the Linux kernel should gets passed 3891 the now "corrected" memory size and won't touch it either. 3892 This should work for arch/ppc and arch/powerpc. Only Linux 3893 board ports in arch/powerpc with bootwrapper support that 3894 recalculate the memory size from the SDRAM controller setup 3895 will have to get fixed in Linux additionally. 3896 3897 This option can be used as a workaround for the 440EPx/GRx 3898 CHIP 11 errata where the last 256 bytes in SDRAM shouldn't 3899 be touched. 3900 3901 WARNING: Please make sure that this value is a multiple of 3902 the Linux page size (normally 4k). If this is not the case, 3903 then the end address of the Linux memory will be located at a 3904 non page size aligned address and this could cause major 3905 problems. 3906 3907- CONFIG_SYS_LOADS_BAUD_CHANGE: 3908 Enable temporary baudrate change while serial download 3909 3910- CONFIG_SYS_SDRAM_BASE: 3911 Physical start address of SDRAM. _Must_ be 0 here. 3912 3913- CONFIG_SYS_MBIO_BASE: 3914 Physical start address of Motherboard I/O (if using a 3915 Cogent motherboard) 3916 3917- CONFIG_SYS_FLASH_BASE: 3918 Physical start address of Flash memory. 3919 3920- CONFIG_SYS_MONITOR_BASE: 3921 Physical start address of boot monitor code (set by 3922 make config files to be same as the text base address 3923 (CONFIG_SYS_TEXT_BASE) used when linking) - same as 3924 CONFIG_SYS_FLASH_BASE when booting from flash. 3925 3926- CONFIG_SYS_MONITOR_LEN: 3927 Size of memory reserved for monitor code, used to 3928 determine _at_compile_time_ (!) if the environment is 3929 embedded within the U-Boot image, or in a separate 3930 flash sector. 3931 3932- CONFIG_SYS_MALLOC_LEN: 3933 Size of DRAM reserved for malloc() use. 3934 3935- CONFIG_SYS_MALLOC_F_LEN 3936 Size of the malloc() pool for use before relocation. If 3937 this is defined, then a very simple malloc() implementation 3938 will become available before relocation. The address is just 3939 below the global data, and the stack is moved down to make 3940 space. 3941 3942 This feature allocates regions with increasing addresses 3943 within the region. calloc() is supported, but realloc() 3944 is not available. free() is supported but does nothing. 3945 The memory will be freed (or in fact just forgotten) when 3946 U-Boot relocates itself. 3947 3948 Pre-relocation malloc() is only supported on ARM and sandbox 3949 at present but is fairly easy to enable for other archs. 3950 3951- CONFIG_SYS_MALLOC_SIMPLE 3952 Provides a simple and small malloc() and calloc() for those 3953 boards which do not use the full malloc in SPL (which is 3954 enabled with CONFIG_SYS_SPL_MALLOC_START). 3955 3956- CONFIG_SYS_NONCACHED_MEMORY: 3957 Size of non-cached memory area. This area of memory will be 3958 typically located right below the malloc() area and mapped 3959 uncached in the MMU. This is useful for drivers that would 3960 otherwise require a lot of explicit cache maintenance. For 3961 some drivers it's also impossible to properly maintain the 3962 cache. For example if the regions that need to be flushed 3963 are not a multiple of the cache-line size, *and* padding 3964 cannot be allocated between the regions to align them (i.e. 3965 if the HW requires a contiguous array of regions, and the 3966 size of each region is not cache-aligned), then a flush of 3967 one region may result in overwriting data that hardware has 3968 written to another region in the same cache-line. This can 3969 happen for example in network drivers where descriptors for 3970 buffers are typically smaller than the CPU cache-line (e.g. 3971 16 bytes vs. 32 or 64 bytes). 3972 3973 Non-cached memory is only supported on 32-bit ARM at present. 3974 3975- CONFIG_SYS_BOOTM_LEN: 3976 Normally compressed uImages are limited to an 3977 uncompressed size of 8 MBytes. If this is not enough, 3978 you can define CONFIG_SYS_BOOTM_LEN in your board config file 3979 to adjust this setting to your needs. 3980 3981- CONFIG_SYS_BOOTMAPSZ: 3982 Maximum size of memory mapped by the startup code of 3983 the Linux kernel; all data that must be processed by 3984 the Linux kernel (bd_info, boot arguments, FDT blob if 3985 used) must be put below this limit, unless "bootm_low" 3986 environment variable is defined and non-zero. In such case 3987 all data for the Linux kernel must be between "bootm_low" 3988 and "bootm_low" + CONFIG_SYS_BOOTMAPSZ. The environment 3989 variable "bootm_mapsize" will override the value of 3990 CONFIG_SYS_BOOTMAPSZ. If CONFIG_SYS_BOOTMAPSZ is undefined, 3991 then the value in "bootm_size" will be used instead. 3992 3993- CONFIG_SYS_BOOT_RAMDISK_HIGH: 3994 Enable initrd_high functionality. If defined then the 3995 initrd_high feature is enabled and the bootm ramdisk subcommand 3996 is enabled. 3997 3998- CONFIG_SYS_BOOT_GET_CMDLINE: 3999 Enables allocating and saving kernel cmdline in space between 4000 "bootm_low" and "bootm_low" + BOOTMAPSZ. 4001 4002- CONFIG_SYS_BOOT_GET_KBD: 4003 Enables allocating and saving a kernel copy of the bd_info in 4004 space between "bootm_low" and "bootm_low" + BOOTMAPSZ. 4005 4006- CONFIG_SYS_MAX_FLASH_BANKS: 4007 Max number of Flash memory banks 4008 4009- CONFIG_SYS_MAX_FLASH_SECT: 4010 Max number of sectors on a Flash chip 4011 4012- CONFIG_SYS_FLASH_ERASE_TOUT: 4013 Timeout for Flash erase operations (in ms) 4014 4015- CONFIG_SYS_FLASH_WRITE_TOUT: 4016 Timeout for Flash write operations (in ms) 4017 4018- CONFIG_SYS_FLASH_LOCK_TOUT 4019 Timeout for Flash set sector lock bit operation (in ms) 4020 4021- CONFIG_SYS_FLASH_UNLOCK_TOUT 4022 Timeout for Flash clear lock bits operation (in ms) 4023 4024- CONFIG_SYS_FLASH_PROTECTION 4025 If defined, hardware flash sectors protection is used 4026 instead of U-Boot software protection. 4027 4028- CONFIG_SYS_DIRECT_FLASH_TFTP: 4029 4030 Enable TFTP transfers directly to flash memory; 4031 without this option such a download has to be 4032 performed in two steps: (1) download to RAM, and (2) 4033 copy from RAM to flash. 4034 4035 The two-step approach is usually more reliable, since 4036 you can check if the download worked before you erase 4037 the flash, but in some situations (when system RAM is 4038 too limited to allow for a temporary copy of the 4039 downloaded image) this option may be very useful. 4040 4041- CONFIG_SYS_FLASH_CFI: 4042 Define if the flash driver uses extra elements in the 4043 common flash structure for storing flash geometry. 4044 4045- CONFIG_FLASH_CFI_DRIVER 4046 This option also enables the building of the cfi_flash driver 4047 in the drivers directory 4048 4049- CONFIG_FLASH_CFI_MTD 4050 This option enables the building of the cfi_mtd driver 4051 in the drivers directory. The driver exports CFI flash 4052 to the MTD layer. 4053 4054- CONFIG_SYS_FLASH_USE_BUFFER_WRITE 4055 Use buffered writes to flash. 4056 4057- CONFIG_FLASH_SPANSION_S29WS_N 4058 s29ws-n MirrorBit flash has non-standard addresses for buffered 4059 write commands. 4060 4061- CONFIG_SYS_FLASH_QUIET_TEST 4062 If this option is defined, the common CFI flash doesn't 4063 print it's warning upon not recognized FLASH banks. This 4064 is useful, if some of the configured banks are only 4065 optionally available. 4066 4067- CONFIG_FLASH_SHOW_PROGRESS 4068 If defined (must be an integer), print out countdown 4069 digits and dots. Recommended value: 45 (9..1) for 80 4070 column displays, 15 (3..1) for 40 column displays. 4071 4072- CONFIG_FLASH_VERIFY 4073 If defined, the content of the flash (destination) is compared 4074 against the source after the write operation. An error message 4075 will be printed when the contents are not identical. 4076 Please note that this option is useless in nearly all cases, 4077 since such flash programming errors usually are detected earlier 4078 while unprotecting/erasing/programming. Please only enable 4079 this option if you really know what you are doing. 4080 4081- CONFIG_SYS_RX_ETH_BUFFER: 4082 Defines the number of Ethernet receive buffers. On some 4083 Ethernet controllers it is recommended to set this value 4084 to 8 or even higher (EEPRO100 or 405 EMAC), since all 4085 buffers can be full shortly after enabling the interface 4086 on high Ethernet traffic. 4087 Defaults to 4 if not defined. 4088 4089- CONFIG_ENV_MAX_ENTRIES 4090 4091 Maximum number of entries in the hash table that is used 4092 internally to store the environment settings. The default 4093 setting is supposed to be generous and should work in most 4094 cases. This setting can be used to tune behaviour; see 4095 lib/hashtable.c for details. 4096 4097- CONFIG_ENV_FLAGS_LIST_DEFAULT 4098- CONFIG_ENV_FLAGS_LIST_STATIC 4099 Enable validation of the values given to environment variables when 4100 calling env set. Variables can be restricted to only decimal, 4101 hexadecimal, or boolean. If CONFIG_CMD_NET is also defined, 4102 the variables can also be restricted to IP address or MAC address. 4103 4104 The format of the list is: 4105 type_attribute = [s|d|x|b|i|m] 4106 access_attribute = [a|r|o|c] 4107 attributes = type_attribute[access_attribute] 4108 entry = variable_name[:attributes] 4109 list = entry[,list] 4110 4111 The type attributes are: 4112 s - String (default) 4113 d - Decimal 4114 x - Hexadecimal 4115 b - Boolean ([1yYtT|0nNfF]) 4116 i - IP address 4117 m - MAC address 4118 4119 The access attributes are: 4120 a - Any (default) 4121 r - Read-only 4122 o - Write-once 4123 c - Change-default 4124 4125 - CONFIG_ENV_FLAGS_LIST_DEFAULT 4126 Define this to a list (string) to define the ".flags" 4127 environment variable in the default or embedded environment. 4128 4129 - CONFIG_ENV_FLAGS_LIST_STATIC 4130 Define this to a list (string) to define validation that 4131 should be done if an entry is not found in the ".flags" 4132 environment variable. To override a setting in the static 4133 list, simply add an entry for the same variable name to the 4134 ".flags" variable. 4135 4136 If CONFIG_REGEX is defined, the variable_name above is evaluated as a 4137 regular expression. This allows multiple variables to define the same 4138 flags without explicitly listing them for each variable. 4139 4140- CONFIG_ENV_ACCESS_IGNORE_FORCE 4141 If defined, don't allow the -f switch to env set override variable 4142 access flags. 4143 4144- CONFIG_SYS_GENERIC_BOARD 4145 This selects the architecture-generic board system instead of the 4146 architecture-specific board files. It is intended to move boards 4147 to this new framework over time. Defining this will disable the 4148 arch/foo/lib/board.c file and use common/board_f.c and 4149 common/board_r.c instead. To use this option your architecture 4150 must support it (i.e. must select HAVE_GENERIC_BOARD in arch/Kconfig). 4151 If you find problems enabling this option on your board please report 4152 the problem and send patches! 4153 4154- CONFIG_OMAP_PLATFORM_RESET_TIME_MAX_USEC (OMAP only) 4155 This is set by OMAP boards for the max time that reset should 4156 be asserted. See doc/README.omap-reset-time for details on how 4157 the value can be calculated on a given board. 4158 4159- CONFIG_USE_STDINT 4160 If stdint.h is available with your toolchain you can define this 4161 option to enable it. You can provide option 'USE_STDINT=1' when 4162 building U-Boot to enable this. 4163 4164The following definitions that deal with the placement and management 4165of environment data (variable area); in general, we support the 4166following configurations: 4167 4168- CONFIG_BUILD_ENVCRC: 4169 4170 Builds up envcrc with the target environment so that external utils 4171 may easily extract it and embed it in final U-Boot images. 4172 4173- CONFIG_ENV_IS_IN_FLASH: 4174 4175 Define this if the environment is in flash memory. 4176 4177 a) The environment occupies one whole flash sector, which is 4178 "embedded" in the text segment with the U-Boot code. This 4179 happens usually with "bottom boot sector" or "top boot 4180 sector" type flash chips, which have several smaller 4181 sectors at the start or the end. For instance, such a 4182 layout can have sector sizes of 8, 2x4, 16, Nx32 kB. In 4183 such a case you would place the environment in one of the 4184 4 kB sectors - with U-Boot code before and after it. With 4185 "top boot sector" type flash chips, you would put the 4186 environment in one of the last sectors, leaving a gap 4187 between U-Boot and the environment. 4188 4189 - CONFIG_ENV_OFFSET: 4190 4191 Offset of environment data (variable area) to the 4192 beginning of flash memory; for instance, with bottom boot 4193 type flash chips the second sector can be used: the offset 4194 for this sector is given here. 4195 4196 CONFIG_ENV_OFFSET is used relative to CONFIG_SYS_FLASH_BASE. 4197 4198 - CONFIG_ENV_ADDR: 4199 4200 This is just another way to specify the start address of 4201 the flash sector containing the environment (instead of 4202 CONFIG_ENV_OFFSET). 4203 4204 - CONFIG_ENV_SECT_SIZE: 4205 4206 Size of the sector containing the environment. 4207 4208 4209 b) Sometimes flash chips have few, equal sized, BIG sectors. 4210 In such a case you don't want to spend a whole sector for 4211 the environment. 4212 4213 - CONFIG_ENV_SIZE: 4214 4215 If you use this in combination with CONFIG_ENV_IS_IN_FLASH 4216 and CONFIG_ENV_SECT_SIZE, you can specify to use only a part 4217 of this flash sector for the environment. This saves 4218 memory for the RAM copy of the environment. 4219 4220 It may also save flash memory if you decide to use this 4221 when your environment is "embedded" within U-Boot code, 4222 since then the remainder of the flash sector could be used 4223 for U-Boot code. It should be pointed out that this is 4224 STRONGLY DISCOURAGED from a robustness point of view: 4225 updating the environment in flash makes it always 4226 necessary to erase the WHOLE sector. If something goes 4227 wrong before the contents has been restored from a copy in 4228 RAM, your target system will be dead. 4229 4230 - CONFIG_ENV_ADDR_REDUND 4231 CONFIG_ENV_SIZE_REDUND 4232 4233 These settings describe a second storage area used to hold 4234 a redundant copy of the environment data, so that there is 4235 a valid backup copy in case there is a power failure during 4236 a "saveenv" operation. 4237 4238BE CAREFUL! Any changes to the flash layout, and some changes to the 4239source code will make it necessary to adapt <board>/u-boot.lds* 4240accordingly! 4241 4242 4243- CONFIG_ENV_IS_IN_NVRAM: 4244 4245 Define this if you have some non-volatile memory device 4246 (NVRAM, battery buffered SRAM) which you want to use for the 4247 environment. 4248 4249 - CONFIG_ENV_ADDR: 4250 - CONFIG_ENV_SIZE: 4251 4252 These two #defines are used to determine the memory area you 4253 want to use for environment. It is assumed that this memory 4254 can just be read and written to, without any special 4255 provision. 4256 4257BE CAREFUL! The first access to the environment happens quite early 4258in U-Boot initialization (when we try to get the setting of for the 4259console baudrate). You *MUST* have mapped your NVRAM area then, or 4260U-Boot will hang. 4261 4262Please note that even with NVRAM we still use a copy of the 4263environment in RAM: we could work on NVRAM directly, but we want to 4264keep settings there always unmodified except somebody uses "saveenv" 4265to save the current settings. 4266 4267 4268- CONFIG_ENV_IS_IN_EEPROM: 4269 4270 Use this if you have an EEPROM or similar serial access 4271 device and a driver for it. 4272 4273 - CONFIG_ENV_OFFSET: 4274 - CONFIG_ENV_SIZE: 4275 4276 These two #defines specify the offset and size of the 4277 environment area within the total memory of your EEPROM. 4278 4279 - CONFIG_SYS_I2C_EEPROM_ADDR: 4280 If defined, specified the chip address of the EEPROM device. 4281 The default address is zero. 4282 4283 - CONFIG_SYS_I2C_EEPROM_BUS: 4284 If defined, specified the i2c bus of the EEPROM device. 4285 4286 - CONFIG_SYS_EEPROM_PAGE_WRITE_BITS: 4287 If defined, the number of bits used to address bytes in a 4288 single page in the EEPROM device. A 64 byte page, for example 4289 would require six bits. 4290 4291 - CONFIG_SYS_EEPROM_PAGE_WRITE_DELAY_MS: 4292 If defined, the number of milliseconds to delay between 4293 page writes. The default is zero milliseconds. 4294 4295 - CONFIG_SYS_I2C_EEPROM_ADDR_LEN: 4296 The length in bytes of the EEPROM memory array address. Note 4297 that this is NOT the chip address length! 4298 4299 - CONFIG_SYS_I2C_EEPROM_ADDR_OVERFLOW: 4300 EEPROM chips that implement "address overflow" are ones 4301 like Catalyst 24WC04/08/16 which has 9/10/11 bits of 4302 address and the extra bits end up in the "chip address" bit 4303 slots. This makes a 24WC08 (1Kbyte) chip look like four 256 4304 byte chips. 4305 4306 Note that we consider the length of the address field to 4307 still be one byte because the extra address bits are hidden 4308 in the chip address. 4309 4310 - CONFIG_SYS_EEPROM_SIZE: 4311 The size in bytes of the EEPROM device. 4312 4313 - CONFIG_ENV_EEPROM_IS_ON_I2C 4314 define this, if you have I2C and SPI activated, and your 4315 EEPROM, which holds the environment, is on the I2C bus. 4316 4317 - CONFIG_I2C_ENV_EEPROM_BUS 4318 if you have an Environment on an EEPROM reached over 4319 I2C muxes, you can define here, how to reach this 4320 EEPROM. For example: 4321 4322 #define CONFIG_I2C_ENV_EEPROM_BUS 1 4323 4324 EEPROM which holds the environment, is reached over 4325 a pca9547 i2c mux with address 0x70, channel 3. 4326 4327- CONFIG_ENV_IS_IN_DATAFLASH: 4328 4329 Define this if you have a DataFlash memory device which you 4330 want to use for the environment. 4331 4332 - CONFIG_ENV_OFFSET: 4333 - CONFIG_ENV_ADDR: 4334 - CONFIG_ENV_SIZE: 4335 4336 These three #defines specify the offset and size of the 4337 environment area within the total memory of your DataFlash placed 4338 at the specified address. 4339 4340- CONFIG_ENV_IS_IN_SPI_FLASH: 4341 4342 Define this if you have a SPI Flash memory device which you 4343 want to use for the environment. 4344 4345 - CONFIG_ENV_OFFSET: 4346 - CONFIG_ENV_SIZE: 4347 4348 These two #defines specify the offset and size of the 4349 environment area within the SPI Flash. CONFIG_ENV_OFFSET must be 4350 aligned to an erase sector boundary. 4351 4352 - CONFIG_ENV_SECT_SIZE: 4353 4354 Define the SPI flash's sector size. 4355 4356 - CONFIG_ENV_OFFSET_REDUND (optional): 4357 4358 This setting describes a second storage area of CONFIG_ENV_SIZE 4359 size used to hold a redundant copy of the environment data, so 4360 that there is a valid backup copy in case there is a power failure 4361 during a "saveenv" operation. CONFIG_ENV_OFFSET_RENDUND must be 4362 aligned to an erase sector boundary. 4363 4364 - CONFIG_ENV_SPI_BUS (optional): 4365 - CONFIG_ENV_SPI_CS (optional): 4366 4367 Define the SPI bus and chip select. If not defined they will be 0. 4368 4369 - CONFIG_ENV_SPI_MAX_HZ (optional): 4370 4371 Define the SPI max work clock. If not defined then use 1MHz. 4372 4373 - CONFIG_ENV_SPI_MODE (optional): 4374 4375 Define the SPI work mode. If not defined then use SPI_MODE_3. 4376 4377- CONFIG_ENV_IS_IN_REMOTE: 4378 4379 Define this if you have a remote memory space which you 4380 want to use for the local device's environment. 4381 4382 - CONFIG_ENV_ADDR: 4383 - CONFIG_ENV_SIZE: 4384 4385 These two #defines specify the address and size of the 4386 environment area within the remote memory space. The 4387 local device can get the environment from remote memory 4388 space by SRIO or PCIE links. 4389 4390BE CAREFUL! For some special cases, the local device can not use 4391"saveenv" command. For example, the local device will get the 4392environment stored in a remote NOR flash by SRIO or PCIE link, 4393but it can not erase, write this NOR flash by SRIO or PCIE interface. 4394 4395- CONFIG_ENV_IS_IN_NAND: 4396 4397 Define this if you have a NAND device which you want to use 4398 for the environment. 4399 4400 - CONFIG_ENV_OFFSET: 4401 - CONFIG_ENV_SIZE: 4402 4403 These two #defines specify the offset and size of the environment 4404 area within the first NAND device. CONFIG_ENV_OFFSET must be 4405 aligned to an erase block boundary. 4406 4407 - CONFIG_ENV_OFFSET_REDUND (optional): 4408 4409 This setting describes a second storage area of CONFIG_ENV_SIZE 4410 size used to hold a redundant copy of the environment data, so 4411 that there is a valid backup copy in case there is a power failure 4412 during a "saveenv" operation. CONFIG_ENV_OFFSET_RENDUND must be 4413 aligned to an erase block boundary. 4414 4415 - CONFIG_ENV_RANGE (optional): 4416 4417 Specifies the length of the region in which the environment 4418 can be written. This should be a multiple of the NAND device's 4419 block size. Specifying a range with more erase blocks than 4420 are needed to hold CONFIG_ENV_SIZE allows bad blocks within 4421 the range to be avoided. 4422 4423 - CONFIG_ENV_OFFSET_OOB (optional): 4424 4425 Enables support for dynamically retrieving the offset of the 4426 environment from block zero's out-of-band data. The 4427 "nand env.oob" command can be used to record this offset. 4428 Currently, CONFIG_ENV_OFFSET_REDUND is not supported when 4429 using CONFIG_ENV_OFFSET_OOB. 4430 4431- CONFIG_NAND_ENV_DST 4432 4433 Defines address in RAM to which the nand_spl code should copy the 4434 environment. If redundant environment is used, it will be copied to 4435 CONFIG_NAND_ENV_DST + CONFIG_ENV_SIZE. 4436 4437- CONFIG_ENV_IS_IN_UBI: 4438 4439 Define this if you have an UBI volume that you want to use for the 4440 environment. This has the benefit of wear-leveling the environment 4441 accesses, which is important on NAND. 4442 4443 - CONFIG_ENV_UBI_PART: 4444 4445 Define this to a string that is the mtd partition containing the UBI. 4446 4447 - CONFIG_ENV_UBI_VOLUME: 4448 4449 Define this to the name of the volume that you want to store the 4450 environment in. 4451 4452 - CONFIG_ENV_UBI_VOLUME_REDUND: 4453 4454 Define this to the name of another volume to store a second copy of 4455 the environment in. This will enable redundant environments in UBI. 4456 It is assumed that both volumes are in the same MTD partition. 4457 4458 - CONFIG_UBI_SILENCE_MSG 4459 - CONFIG_UBIFS_SILENCE_MSG 4460 4461 You will probably want to define these to avoid a really noisy system 4462 when storing the env in UBI. 4463 4464- CONFIG_ENV_IS_IN_FAT: 4465 Define this if you want to use the FAT file system for the environment. 4466 4467 - FAT_ENV_INTERFACE: 4468 4469 Define this to a string that is the name of the block device. 4470 4471 - FAT_ENV_DEV_AND_PART: 4472 4473 Define this to a string to specify the partition of the device. It can 4474 be as following: 4475 4476 "D:P", "D:0", "D", "D:" or "D:auto" (D, P are integers. And P >= 1) 4477 - "D:P": device D partition P. Error occurs if device D has no 4478 partition table. 4479 - "D:0": device D. 4480 - "D" or "D:": device D partition 1 if device D has partition 4481 table, or the whole device D if has no partition 4482 table. 4483 - "D:auto": first partition in device D with bootable flag set. 4484 If none, first valid partition in device D. If no 4485 partition table then means device D. 4486 4487 - FAT_ENV_FILE: 4488 4489 It's a string of the FAT file name. This file use to store the 4490 environment. 4491 4492 - CONFIG_FAT_WRITE: 4493 This should be defined. Otherwise it cannot save the environment file. 4494 4495- CONFIG_ENV_IS_IN_MMC: 4496 4497 Define this if you have an MMC device which you want to use for the 4498 environment. 4499 4500 - CONFIG_SYS_MMC_ENV_DEV: 4501 4502 Specifies which MMC device the environment is stored in. 4503 4504 - CONFIG_SYS_MMC_ENV_PART (optional): 4505 4506 Specifies which MMC partition the environment is stored in. If not 4507 set, defaults to partition 0, the user area. Common values might be 4508 1 (first MMC boot partition), 2 (second MMC boot partition). 4509 4510 - CONFIG_ENV_OFFSET: 4511 - CONFIG_ENV_SIZE: 4512 4513 These two #defines specify the offset and size of the environment 4514 area within the specified MMC device. 4515 4516 If offset is positive (the usual case), it is treated as relative to 4517 the start of the MMC partition. If offset is negative, it is treated 4518 as relative to the end of the MMC partition. This can be useful if 4519 your board may be fitted with different MMC devices, which have 4520 different sizes for the MMC partitions, and you always want the 4521 environment placed at the very end of the partition, to leave the 4522 maximum possible space before it, to store other data. 4523 4524 These two values are in units of bytes, but must be aligned to an 4525 MMC sector boundary. 4526 4527 - CONFIG_ENV_OFFSET_REDUND (optional): 4528 4529 Specifies a second storage area, of CONFIG_ENV_SIZE size, used to 4530 hold a redundant copy of the environment data. This provides a 4531 valid backup copy in case the other copy is corrupted, e.g. due 4532 to a power failure during a "saveenv" operation. 4533 4534 This value may also be positive or negative; this is handled in the 4535 same way as CONFIG_ENV_OFFSET. 4536 4537 This value is also in units of bytes, but must also be aligned to 4538 an MMC sector boundary. 4539 4540 - CONFIG_ENV_SIZE_REDUND (optional): 4541 4542 This value need not be set, even when CONFIG_ENV_OFFSET_REDUND is 4543 set. If this value is set, it must be set to the same value as 4544 CONFIG_ENV_SIZE. 4545 4546- CONFIG_SYS_SPI_INIT_OFFSET 4547 4548 Defines offset to the initial SPI buffer area in DPRAM. The 4549 area is used at an early stage (ROM part) if the environment 4550 is configured to reside in the SPI EEPROM: We need a 520 byte 4551 scratch DPRAM area. It is used between the two initialization 4552 calls (spi_init_f() and spi_init_r()). A value of 0xB00 seems 4553 to be a good choice since it makes it far enough from the 4554 start of the data area as well as from the stack pointer. 4555 4556Please note that the environment is read-only until the monitor 4557has been relocated to RAM and a RAM copy of the environment has been 4558created; also, when using EEPROM you will have to use getenv_f() 4559until then to read environment variables. 4560 4561The environment is protected by a CRC32 checksum. Before the monitor 4562is relocated into RAM, as a result of a bad CRC you will be working 4563with the compiled-in default environment - *silently*!!! [This is 4564necessary, because the first environment variable we need is the 4565"baudrate" setting for the console - if we have a bad CRC, we don't 4566have any device yet where we could complain.] 4567 4568Note: once the monitor has been relocated, then it will complain if 4569the default environment is used; a new CRC is computed as soon as you 4570use the "saveenv" command to store a valid environment. 4571 4572- CONFIG_SYS_FAULT_ECHO_LINK_DOWN: 4573 Echo the inverted Ethernet link state to the fault LED. 4574 4575 Note: If this option is active, then CONFIG_SYS_FAULT_MII_ADDR 4576 also needs to be defined. 4577 4578- CONFIG_SYS_FAULT_MII_ADDR: 4579 MII address of the PHY to check for the Ethernet link state. 4580 4581- CONFIG_NS16550_MIN_FUNCTIONS: 4582 Define this if you desire to only have use of the NS16550_init 4583 and NS16550_putc functions for the serial driver located at 4584 drivers/serial/ns16550.c. This option is useful for saving 4585 space for already greatly restricted images, including but not 4586 limited to NAND_SPL configurations. 4587 4588- CONFIG_DISPLAY_BOARDINFO 4589 Display information about the board that U-Boot is running on 4590 when U-Boot starts up. The board function checkboard() is called 4591 to do this. 4592 4593- CONFIG_DISPLAY_BOARDINFO_LATE 4594 Similar to the previous option, but display this information 4595 later, once stdio is running and output goes to the LCD, if 4596 present. 4597 4598- CONFIG_BOARD_SIZE_LIMIT: 4599 Maximum size of the U-Boot image. When defined, the 4600 build system checks that the actual size does not 4601 exceed it. 4602 4603Low Level (hardware related) configuration options: 4604--------------------------------------------------- 4605 4606- CONFIG_SYS_CACHELINE_SIZE: 4607 Cache Line Size of the CPU. 4608 4609- CONFIG_SYS_DEFAULT_IMMR: 4610 Default address of the IMMR after system reset. 4611 4612 Needed on some 8260 systems (MPC8260ADS, PQ2FADS-ZU, 4613 and RPXsuper) to be able to adjust the position of 4614 the IMMR register after a reset. 4615 4616- CONFIG_SYS_CCSRBAR_DEFAULT: 4617 Default (power-on reset) physical address of CCSR on Freescale 4618 PowerPC SOCs. 4619 4620- CONFIG_SYS_CCSRBAR: 4621 Virtual address of CCSR. On a 32-bit build, this is typically 4622 the same value as CONFIG_SYS_CCSRBAR_DEFAULT. 4623 4624 CONFIG_SYS_DEFAULT_IMMR must also be set to this value, 4625 for cross-platform code that uses that macro instead. 4626 4627- CONFIG_SYS_CCSRBAR_PHYS: 4628 Physical address of CCSR. CCSR can be relocated to a new 4629 physical address, if desired. In this case, this macro should 4630 be set to that address. Otherwise, it should be set to the 4631 same value as CONFIG_SYS_CCSRBAR_DEFAULT. For example, CCSR 4632 is typically relocated on 36-bit builds. It is recommended 4633 that this macro be defined via the _HIGH and _LOW macros: 4634 4635 #define CONFIG_SYS_CCSRBAR_PHYS ((CONFIG_SYS_CCSRBAR_PHYS_HIGH 4636 * 1ull) << 32 | CONFIG_SYS_CCSRBAR_PHYS_LOW) 4637 4638- CONFIG_SYS_CCSRBAR_PHYS_HIGH: 4639 Bits 33-36 of CONFIG_SYS_CCSRBAR_PHYS. This value is typically 4640 either 0 (32-bit build) or 0xF (36-bit build). This macro is 4641 used in assembly code, so it must not contain typecasts or 4642 integer size suffixes (e.g. "ULL"). 4643 4644- CONFIG_SYS_CCSRBAR_PHYS_LOW: 4645 Lower 32-bits of CONFIG_SYS_CCSRBAR_PHYS. This macro is 4646 used in assembly code, so it must not contain typecasts or 4647 integer size suffixes (e.g. "ULL"). 4648 4649- CONFIG_SYS_CCSR_DO_NOT_RELOCATE: 4650 If this macro is defined, then CONFIG_SYS_CCSRBAR_PHYS will be 4651 forced to a value that ensures that CCSR is not relocated. 4652 4653- Floppy Disk Support: 4654 CONFIG_SYS_FDC_DRIVE_NUMBER 4655 4656 the default drive number (default value 0) 4657 4658 CONFIG_SYS_ISA_IO_STRIDE 4659 4660 defines the spacing between FDC chipset registers 4661 (default value 1) 4662 4663 CONFIG_SYS_ISA_IO_OFFSET 4664 4665 defines the offset of register from address. It 4666 depends on which part of the data bus is connected to 4667 the FDC chipset. (default value 0) 4668 4669 If CONFIG_SYS_ISA_IO_STRIDE CONFIG_SYS_ISA_IO_OFFSET and 4670 CONFIG_SYS_FDC_DRIVE_NUMBER are undefined, they take their 4671 default value. 4672 4673 if CONFIG_SYS_FDC_HW_INIT is defined, then the function 4674 fdc_hw_init() is called at the beginning of the FDC 4675 setup. fdc_hw_init() must be provided by the board 4676 source code. It is used to make hardware-dependent 4677 initializations. 4678 4679- CONFIG_IDE_AHB: 4680 Most IDE controllers were designed to be connected with PCI 4681 interface. Only few of them were designed for AHB interface. 4682 When software is doing ATA command and data transfer to 4683 IDE devices through IDE-AHB controller, some additional 4684 registers accessing to these kind of IDE-AHB controller 4685 is required. 4686 4687- CONFIG_SYS_IMMR: Physical address of the Internal Memory. 4688 DO NOT CHANGE unless you know exactly what you're 4689 doing! (11-4) [MPC8xx/82xx systems only] 4690 4691- CONFIG_SYS_INIT_RAM_ADDR: 4692 4693 Start address of memory area that can be used for 4694 initial data and stack; please note that this must be 4695 writable memory that is working WITHOUT special 4696 initialization, i. e. you CANNOT use normal RAM which 4697 will become available only after programming the 4698 memory controller and running certain initialization 4699 sequences. 4700 4701 U-Boot uses the following memory types: 4702 - MPC8xx and MPC8260: IMMR (internal memory of the CPU) 4703 - MPC824X: data cache 4704 - PPC4xx: data cache 4705 4706- CONFIG_SYS_GBL_DATA_OFFSET: 4707 4708 Offset of the initial data structure in the memory 4709 area defined by CONFIG_SYS_INIT_RAM_ADDR. Usually 4710 CONFIG_SYS_GBL_DATA_OFFSET is chosen such that the initial 4711 data is located at the end of the available space 4712 (sometimes written as (CONFIG_SYS_INIT_RAM_SIZE - 4713 CONFIG_SYS_INIT_DATA_SIZE), and the initial stack is just 4714 below that area (growing from (CONFIG_SYS_INIT_RAM_ADDR + 4715 CONFIG_SYS_GBL_DATA_OFFSET) downward. 4716 4717 Note: 4718 On the MPC824X (or other systems that use the data 4719 cache for initial memory) the address chosen for 4720 CONFIG_SYS_INIT_RAM_ADDR is basically arbitrary - it must 4721 point to an otherwise UNUSED address space between 4722 the top of RAM and the start of the PCI space. 4723 4724- CONFIG_SYS_SIUMCR: SIU Module Configuration (11-6) 4725 4726- CONFIG_SYS_SYPCR: System Protection Control (11-9) 4727 4728- CONFIG_SYS_TBSCR: Time Base Status and Control (11-26) 4729 4730- CONFIG_SYS_PISCR: Periodic Interrupt Status and Control (11-31) 4731 4732- CONFIG_SYS_PLPRCR: PLL, Low-Power, and Reset Control Register (15-30) 4733 4734- CONFIG_SYS_SCCR: System Clock and reset Control Register (15-27) 4735 4736- CONFIG_SYS_OR_TIMING_SDRAM: 4737 SDRAM timing 4738 4739- CONFIG_SYS_MAMR_PTA: 4740 periodic timer for refresh 4741 4742- CONFIG_SYS_DER: Debug Event Register (37-47) 4743 4744- FLASH_BASE0_PRELIM, FLASH_BASE1_PRELIM, CONFIG_SYS_REMAP_OR_AM, 4745 CONFIG_SYS_PRELIM_OR_AM, CONFIG_SYS_OR_TIMING_FLASH, CONFIG_SYS_OR0_REMAP, 4746 CONFIG_SYS_OR0_PRELIM, CONFIG_SYS_BR0_PRELIM, CONFIG_SYS_OR1_REMAP, CONFIG_SYS_OR1_PRELIM, 4747 CONFIG_SYS_BR1_PRELIM: 4748 Memory Controller Definitions: BR0/1 and OR0/1 (FLASH) 4749 4750- SDRAM_BASE2_PRELIM, SDRAM_BASE3_PRELIM, SDRAM_MAX_SIZE, 4751 CONFIG_SYS_OR_TIMING_SDRAM, CONFIG_SYS_OR2_PRELIM, CONFIG_SYS_BR2_PRELIM, 4752 CONFIG_SYS_OR3_PRELIM, CONFIG_SYS_BR3_PRELIM: 4753 Memory Controller Definitions: BR2/3 and OR2/3 (SDRAM) 4754 4755- CONFIG_SYS_MAMR_PTA, CONFIG_SYS_MPTPR_2BK_4K, CONFIG_SYS_MPTPR_1BK_4K, CONFIG_SYS_MPTPR_2BK_8K, 4756 CONFIG_SYS_MPTPR_1BK_8K, CONFIG_SYS_MAMR_8COL, CONFIG_SYS_MAMR_9COL: 4757 Machine Mode Register and Memory Periodic Timer 4758 Prescaler definitions (SDRAM timing) 4759 4760- CONFIG_SYS_I2C_UCODE_PATCH, CONFIG_SYS_I2C_DPMEM_OFFSET [0x1FC0]: 4761 enable I2C microcode relocation patch (MPC8xx); 4762 define relocation offset in DPRAM [DSP2] 4763 4764- CONFIG_SYS_SMC_UCODE_PATCH, CONFIG_SYS_SMC_DPMEM_OFFSET [0x1FC0]: 4765 enable SMC microcode relocation patch (MPC8xx); 4766 define relocation offset in DPRAM [SMC1] 4767 4768- CONFIG_SYS_SPI_UCODE_PATCH, CONFIG_SYS_SPI_DPMEM_OFFSET [0x1FC0]: 4769 enable SPI microcode relocation patch (MPC8xx); 4770 define relocation offset in DPRAM [SCC4] 4771 4772- CONFIG_SYS_USE_OSCCLK: 4773 Use OSCM clock mode on MBX8xx board. Be careful, 4774 wrong setting might damage your board. Read 4775 doc/README.MBX before setting this variable! 4776 4777- CONFIG_SYS_CPM_POST_WORD_ADDR: (MPC8xx, MPC8260 only) 4778 Offset of the bootmode word in DPRAM used by post 4779 (Power On Self Tests). This definition overrides 4780 #define'd default value in commproc.h resp. 4781 cpm_8260.h. 4782 4783- CONFIG_SYS_PCI_SLV_MEM_LOCAL, CONFIG_SYS_PCI_SLV_MEM_BUS, CONFIG_SYS_PICMR0_MASK_ATTRIB, 4784 CONFIG_SYS_PCI_MSTR0_LOCAL, CONFIG_SYS_PCIMSK0_MASK, CONFIG_SYS_PCI_MSTR1_LOCAL, 4785 CONFIG_SYS_PCIMSK1_MASK, CONFIG_SYS_PCI_MSTR_MEM_LOCAL, CONFIG_SYS_PCI_MSTR_MEM_BUS, 4786 CONFIG_SYS_CPU_PCI_MEM_START, CONFIG_SYS_PCI_MSTR_MEM_SIZE, CONFIG_SYS_POCMR0_MASK_ATTRIB, 4787 CONFIG_SYS_PCI_MSTR_MEMIO_LOCAL, CONFIG_SYS_PCI_MSTR_MEMIO_BUS, CPU_PCI_MEMIO_START, 4788 CONFIG_SYS_PCI_MSTR_MEMIO_SIZE, CONFIG_SYS_POCMR1_MASK_ATTRIB, CONFIG_SYS_PCI_MSTR_IO_LOCAL, 4789 CONFIG_SYS_PCI_MSTR_IO_BUS, CONFIG_SYS_CPU_PCI_IO_START, CONFIG_SYS_PCI_MSTR_IO_SIZE, 4790 CONFIG_SYS_POCMR2_MASK_ATTRIB: (MPC826x only) 4791 Overrides the default PCI memory map in arch/powerpc/cpu/mpc8260/pci.c if set. 4792 4793- CONFIG_PCI_DISABLE_PCIE: 4794 Disable PCI-Express on systems where it is supported but not 4795 required. 4796 4797- CONFIG_PCI_ENUM_ONLY 4798 Only scan through and get the devices on the buses. 4799 Don't do any setup work, presumably because someone or 4800 something has already done it, and we don't need to do it 4801 a second time. Useful for platforms that are pre-booted 4802 by coreboot or similar. 4803 4804- CONFIG_PCI_INDIRECT_BRIDGE: 4805 Enable support for indirect PCI bridges. 4806 4807- CONFIG_SYS_SRIO: 4808 Chip has SRIO or not 4809 4810- CONFIG_SRIO1: 4811 Board has SRIO 1 port available 4812 4813- CONFIG_SRIO2: 4814 Board has SRIO 2 port available 4815 4816- CONFIG_SRIO_PCIE_BOOT_MASTER 4817 Board can support master function for Boot from SRIO and PCIE 4818 4819- CONFIG_SYS_SRIOn_MEM_VIRT: 4820 Virtual Address of SRIO port 'n' memory region 4821 4822- CONFIG_SYS_SRIOn_MEM_PHYS: 4823 Physical Address of SRIO port 'n' memory region 4824 4825- CONFIG_SYS_SRIOn_MEM_SIZE: 4826 Size of SRIO port 'n' memory region 4827 4828- CONFIG_SYS_NAND_BUSWIDTH_16BIT 4829 Defined to tell the NAND controller that the NAND chip is using 4830 a 16 bit bus. 4831 Not all NAND drivers use this symbol. 4832 Example of drivers that use it: 4833 - drivers/mtd/nand/ndfc.c 4834 - drivers/mtd/nand/mxc_nand.c 4835 4836- CONFIG_SYS_NDFC_EBC0_CFG 4837 Sets the EBC0_CFG register for the NDFC. If not defined 4838 a default value will be used. 4839 4840- CONFIG_SPD_EEPROM 4841 Get DDR timing information from an I2C EEPROM. Common 4842 with pluggable memory modules such as SODIMMs 4843 4844 SPD_EEPROM_ADDRESS 4845 I2C address of the SPD EEPROM 4846 4847- CONFIG_SYS_SPD_BUS_NUM 4848 If SPD EEPROM is on an I2C bus other than the first 4849 one, specify here. Note that the value must resolve 4850 to something your driver can deal with. 4851 4852- CONFIG_SYS_DDR_RAW_TIMING 4853 Get DDR timing information from other than SPD. Common with 4854 soldered DDR chips onboard without SPD. DDR raw timing 4855 parameters are extracted from datasheet and hard-coded into 4856 header files or board specific files. 4857 4858- CONFIG_FSL_DDR_INTERACTIVE 4859 Enable interactive DDR debugging. See doc/README.fsl-ddr. 4860 4861- CONFIG_FSL_DDR_SYNC_REFRESH 4862 Enable sync of refresh for multiple controllers. 4863 4864- CONFIG_FSL_DDR_BIST 4865 Enable built-in memory test for Freescale DDR controllers. 4866 4867- CONFIG_SYS_83XX_DDR_USES_CS0 4868 Only for 83xx systems. If specified, then DDR should 4869 be configured using CS0 and CS1 instead of CS2 and CS3. 4870 4871- CONFIG_ETHER_ON_FEC[12] 4872 Define to enable FEC[12] on a 8xx series processor. 4873 4874- CONFIG_FEC[12]_PHY 4875 Define to the hardcoded PHY address which corresponds 4876 to the given FEC; i. e. 4877 #define CONFIG_FEC1_PHY 4 4878 means that the PHY with address 4 is connected to FEC1 4879 4880 When set to -1, means to probe for first available. 4881 4882- CONFIG_FEC[12]_PHY_NORXERR 4883 The PHY does not have a RXERR line (RMII only). 4884 (so program the FEC to ignore it). 4885 4886- CONFIG_RMII 4887 Enable RMII mode for all FECs. 4888 Note that this is a global option, we can't 4889 have one FEC in standard MII mode and another in RMII mode. 4890 4891- CONFIG_CRC32_VERIFY 4892 Add a verify option to the crc32 command. 4893 The syntax is: 4894 4895 => crc32 -v <address> <count> <crc32> 4896 4897 Where address/count indicate a memory area 4898 and crc32 is the correct crc32 which the 4899 area should have. 4900 4901- CONFIG_LOOPW 4902 Add the "loopw" memory command. This only takes effect if 4903 the memory commands are activated globally (CONFIG_CMD_MEM). 4904 4905- CONFIG_MX_CYCLIC 4906 Add the "mdc" and "mwc" memory commands. These are cyclic 4907 "md/mw" commands. 4908 Examples: 4909 4910 => mdc.b 10 4 500 4911 This command will print 4 bytes (10,11,12,13) each 500 ms. 4912 4913 => mwc.l 100 12345678 10 4914 This command will write 12345678 to address 100 all 10 ms. 4915 4916 This only takes effect if the memory commands are activated 4917 globally (CONFIG_CMD_MEM). 4918 4919- CONFIG_SKIP_LOWLEVEL_INIT 4920 [ARM, NDS32, MIPS only] If this variable is defined, then certain 4921 low level initializations (like setting up the memory 4922 controller) are omitted and/or U-Boot does not 4923 relocate itself into RAM. 4924 4925 Normally this variable MUST NOT be defined. The only 4926 exception is when U-Boot is loaded (to RAM) by some 4927 other boot loader or by a debugger which performs 4928 these initializations itself. 4929 4930- CONFIG_SPL_BUILD 4931 Modifies the behaviour of start.S when compiling a loader 4932 that is executed before the actual U-Boot. E.g. when 4933 compiling a NAND SPL. 4934 4935- CONFIG_TPL_BUILD 4936 Modifies the behaviour of start.S when compiling a loader 4937 that is executed after the SPL and before the actual U-Boot. 4938 It is loaded by the SPL. 4939 4940- CONFIG_SYS_MPC85XX_NO_RESETVEC 4941 Only for 85xx systems. If this variable is specified, the section 4942 .resetvec is not kept and the section .bootpg is placed in the 4943 previous 4k of the .text section. 4944 4945- CONFIG_ARCH_MAP_SYSMEM 4946 Generally U-Boot (and in particular the md command) uses 4947 effective address. It is therefore not necessary to regard 4948 U-Boot address as virtual addresses that need to be translated 4949 to physical addresses. However, sandbox requires this, since 4950 it maintains its own little RAM buffer which contains all 4951 addressable memory. This option causes some memory accesses 4952 to be mapped through map_sysmem() / unmap_sysmem(). 4953 4954- CONFIG_USE_ARCH_MEMCPY 4955 CONFIG_USE_ARCH_MEMSET 4956 If these options are used a optimized version of memcpy/memset will 4957 be used if available. These functions may be faster under some 4958 conditions but may increase the binary size. 4959 4960- CONFIG_X86_RESET_VECTOR 4961 If defined, the x86 reset vector code is included. This is not 4962 needed when U-Boot is running from Coreboot. 4963 4964- CONFIG_SYS_MPUCLK 4965 Defines the MPU clock speed (in MHz). 4966 4967 NOTE : currently only supported on AM335x platforms. 4968 4969- CONFIG_SPL_AM33XX_ENABLE_RTC32K_OSC: 4970 Enables the RTC32K OSC on AM33xx based plattforms 4971 4972- CONFIG_SYS_NAND_NO_SUBPAGE_WRITE 4973 Option to disable subpage write in NAND driver 4974 driver that uses this: 4975 drivers/mtd/nand/davinci_nand.c 4976 4977Freescale QE/FMAN Firmware Support: 4978----------------------------------- 4979 4980The Freescale QUICCEngine (QE) and Frame Manager (FMAN) both support the 4981loading of "firmware", which is encoded in the QE firmware binary format. 4982This firmware often needs to be loaded during U-Boot booting, so macros 4983are used to identify the storage device (NOR flash, SPI, etc) and the address 4984within that device. 4985 4986- CONFIG_SYS_FMAN_FW_ADDR 4987 The address in the storage device where the FMAN microcode is located. The 4988 meaning of this address depends on which CONFIG_SYS_QE_FW_IN_xxx macro 4989 is also specified. 4990 4991- CONFIG_SYS_QE_FW_ADDR 4992 The address in the storage device where the QE microcode is located. The 4993 meaning of this address depends on which CONFIG_SYS_QE_FW_IN_xxx macro 4994 is also specified. 4995 4996- CONFIG_SYS_QE_FMAN_FW_LENGTH 4997 The maximum possible size of the firmware. The firmware binary format 4998 has a field that specifies the actual size of the firmware, but it 4999 might not be possible to read any part of the firmware unless some 5000 local storage is allocated to hold the entire firmware first. 5001 5002- CONFIG_SYS_QE_FMAN_FW_IN_NOR 5003 Specifies that QE/FMAN firmware is located in NOR flash, mapped as 5004 normal addressable memory via the LBC. CONFIG_SYS_FMAN_FW_ADDR is the 5005 virtual address in NOR flash. 5006 5007- CONFIG_SYS_QE_FMAN_FW_IN_NAND 5008 Specifies that QE/FMAN firmware is located in NAND flash. 5009 CONFIG_SYS_FMAN_FW_ADDR is the offset within NAND flash. 5010 5011- CONFIG_SYS_QE_FMAN_FW_IN_MMC 5012 Specifies that QE/FMAN firmware is located on the primary SD/MMC 5013 device. CONFIG_SYS_FMAN_FW_ADDR is the byte offset on that device. 5014 5015- CONFIG_SYS_QE_FMAN_FW_IN_SPIFLASH 5016 Specifies that QE/FMAN firmware is located on the primary SPI 5017 device. CONFIG_SYS_FMAN_FW_ADDR is the byte offset on that device. 5018 5019- CONFIG_SYS_QE_FMAN_FW_IN_REMOTE 5020 Specifies that QE/FMAN firmware is located in the remote (master) 5021 memory space. CONFIG_SYS_FMAN_FW_ADDR is a virtual address which 5022 can be mapped from slave TLB->slave LAW->slave SRIO or PCIE outbound 5023 window->master inbound window->master LAW->the ucode address in 5024 master's memory space. 5025 5026Freescale Layerscape Management Complex Firmware Support: 5027--------------------------------------------------------- 5028The Freescale Layerscape Management Complex (MC) supports the loading of 5029"firmware". 5030This firmware often needs to be loaded during U-Boot booting, so macros 5031are used to identify the storage device (NOR flash, SPI, etc) and the address 5032within that device. 5033 5034- CONFIG_FSL_MC_ENET 5035 Enable the MC driver for Layerscape SoCs. 5036 5037- CONFIG_SYS_LS_MC_FW_ADDR 5038 The address in the storage device where the firmware is located. The 5039 meaning of this address depends on which CONFIG_SYS_LS_MC_FW_IN_xxx macro 5040 is also specified. 5041 5042- CONFIG_SYS_LS_MC_FW_LENGTH 5043 The maximum possible size of the firmware. The firmware binary format 5044 has a field that specifies the actual size of the firmware, but it 5045 might not be possible to read any part of the firmware unless some 5046 local storage is allocated to hold the entire firmware first. 5047 5048- CONFIG_SYS_LS_MC_FW_IN_NOR 5049 Specifies that MC firmware is located in NOR flash, mapped as 5050 normal addressable memory via the LBC. CONFIG_SYS_LS_MC_FW_ADDR is the 5051 virtual address in NOR flash. 5052 5053Freescale Layerscape Debug Server Support: 5054------------------------------------------- 5055The Freescale Layerscape Debug Server Support supports the loading of 5056"Debug Server firmware" and triggering SP boot-rom. 5057This firmware often needs to be loaded during U-Boot booting. 5058 5059- CONFIG_FSL_DEBUG_SERVER 5060 Enable the Debug Server for Layerscape SoCs. 5061 5062- CONFIG_SYS_DEBUG_SERVER_DRAM_BLOCK_MIN_SIZE 5063 Define minimum DDR size required for debug server image 5064 5065- CONFIG_SYS_MEM_TOP_HIDE_MIN 5066 Define minimum DDR size to be hided from top of the DDR memory 5067 5068Reproducible builds 5069------------------- 5070 5071In order to achieve reproducible builds, timestamps used in the U-Boot build 5072process have to be set to a fixed value. 5073 5074This is done using the SOURCE_DATE_EPOCH environment variable. 5075SOURCE_DATE_EPOCH is to be set on the build host's shell, not as a configuration 5076option for U-Boot or an environment variable in U-Boot. 5077 5078SOURCE_DATE_EPOCH should be set to a number of seconds since the epoch, in UTC. 5079 5080Building the Software: 5081====================== 5082 5083Building U-Boot has been tested in several native build environments 5084and in many different cross environments. Of course we cannot support 5085all possibly existing versions of cross development tools in all 5086(potentially obsolete) versions. In case of tool chain problems we 5087recommend to use the ELDK (see http://www.denx.de/wiki/DULG/ELDK) 5088which is extensively used to build and test U-Boot. 5089 5090If you are not using a native environment, it is assumed that you 5091have GNU cross compiling tools available in your path. In this case, 5092you must set the environment variable CROSS_COMPILE in your shell. 5093Note that no changes to the Makefile or any other source files are 5094necessary. For example using the ELDK on a 4xx CPU, please enter: 5095 5096 $ CROSS_COMPILE=ppc_4xx- 5097 $ export CROSS_COMPILE 5098 5099Note: If you wish to generate Windows versions of the utilities in 5100 the tools directory you can use the MinGW toolchain 5101 (http://www.mingw.org). Set your HOST tools to the MinGW 5102 toolchain and execute 'make tools'. For example: 5103 5104 $ make HOSTCC=i586-mingw32msvc-gcc HOSTSTRIP=i586-mingw32msvc-strip tools 5105 5106 Binaries such as tools/mkimage.exe will be created which can 5107 be executed on computers running Windows. 5108 5109U-Boot is intended to be simple to build. After installing the 5110sources you must configure U-Boot for one specific board type. This 5111is done by typing: 5112 5113 make NAME_defconfig 5114 5115where "NAME_defconfig" is the name of one of the existing configu- 5116rations; see boards.cfg for supported names. 5117 5118Note: for some board special configuration names may exist; check if 5119 additional information is available from the board vendor; for 5120 instance, the TQM823L systems are available without (standard) 5121 or with LCD support. You can select such additional "features" 5122 when choosing the configuration, i. e. 5123 5124 make TQM823L_defconfig 5125 - will configure for a plain TQM823L, i. e. no LCD support 5126 5127 make TQM823L_LCD_defconfig 5128 - will configure for a TQM823L with U-Boot console on LCD 5129 5130 etc. 5131 5132 5133Finally, type "make all", and you should get some working U-Boot 5134images ready for download to / installation on your system: 5135 5136- "u-boot.bin" is a raw binary image 5137- "u-boot" is an image in ELF binary format 5138- "u-boot.srec" is in Motorola S-Record format 5139 5140By default the build is performed locally and the objects are saved 5141in the source directory. One of the two methods can be used to change 5142this behavior and build U-Boot to some external directory: 5143 51441. Add O= to the make command line invocations: 5145 5146 make O=/tmp/build distclean 5147 make O=/tmp/build NAME_defconfig 5148 make O=/tmp/build all 5149 51502. Set environment variable KBUILD_OUTPUT to point to the desired location: 5151 5152 export KBUILD_OUTPUT=/tmp/build 5153 make distclean 5154 make NAME_defconfig 5155 make all 5156 5157Note that the command line "O=" setting overrides the KBUILD_OUTPUT environment 5158variable. 5159 5160 5161Please be aware that the Makefiles assume you are using GNU make, so 5162for instance on NetBSD you might need to use "gmake" instead of 5163native "make". 5164 5165 5166If the system board that you have is not listed, then you will need 5167to port U-Boot to your hardware platform. To do this, follow these 5168steps: 5169 51701. Add a new configuration option for your board to the toplevel 5171 "boards.cfg" file, using the existing entries as examples. 5172 Follow the instructions there to keep the boards in order. 51732. Create a new directory to hold your board specific code. Add any 5174 files you need. In your board directory, you will need at least 5175 the "Makefile", a "<board>.c", "flash.c" and "u-boot.lds". 51763. Create a new configuration file "include/configs/<board>.h" for 5177 your board 51783. If you're porting U-Boot to a new CPU, then also create a new 5179 directory to hold your CPU specific code. Add any files you need. 51804. Run "make <board>_defconfig" with your new name. 51815. Type "make", and you should get a working "u-boot.srec" file 5182 to be installed on your target system. 51836. Debug and solve any problems that might arise. 5184 [Of course, this last step is much harder than it sounds.] 5185 5186 5187Testing of U-Boot Modifications, Ports to New Hardware, etc.: 5188============================================================== 5189 5190If you have modified U-Boot sources (for instance added a new board 5191or support for new devices, a new CPU, etc.) you are expected to 5192provide feedback to the other developers. The feedback normally takes 5193the form of a "patch", i. e. a context diff against a certain (latest 5194official or latest in the git repository) version of U-Boot sources. 5195 5196But before you submit such a patch, please verify that your modifi- 5197cation did not break existing code. At least make sure that *ALL* of 5198the supported boards compile WITHOUT ANY compiler warnings. To do so, 5199just run the "MAKEALL" script, which will configure and build U-Boot 5200for ALL supported system. Be warned, this will take a while. You can 5201select which (cross) compiler to use by passing a `CROSS_COMPILE' 5202environment variable to the script, i. e. to use the ELDK cross tools 5203you can type 5204 5205 CROSS_COMPILE=ppc_8xx- MAKEALL 5206 5207or to build on a native PowerPC system you can type 5208 5209 CROSS_COMPILE=' ' MAKEALL 5210 5211When using the MAKEALL script, the default behaviour is to build 5212U-Boot in the source directory. This location can be changed by 5213setting the BUILD_DIR environment variable. Also, for each target 5214built, the MAKEALL script saves two log files (<target>.ERR and 5215<target>.MAKEALL) in the <source dir>/LOG directory. This default 5216location can be changed by setting the MAKEALL_LOGDIR environment 5217variable. For example: 5218 5219 export BUILD_DIR=/tmp/build 5220 export MAKEALL_LOGDIR=/tmp/log 5221 CROSS_COMPILE=ppc_8xx- MAKEALL 5222 5223With the above settings build objects are saved in the /tmp/build, 5224log files are saved in the /tmp/log and the source tree remains clean 5225during the whole build process. 5226 5227 5228See also "U-Boot Porting Guide" below. 5229 5230 5231Monitor Commands - Overview: 5232============================ 5233 5234go - start application at address 'addr' 5235run - run commands in an environment variable 5236bootm - boot application image from memory 5237bootp - boot image via network using BootP/TFTP protocol 5238bootz - boot zImage from memory 5239tftpboot- boot image via network using TFTP protocol 5240 and env variables "ipaddr" and "serverip" 5241 (and eventually "gatewayip") 5242tftpput - upload a file via network using TFTP protocol 5243rarpboot- boot image via network using RARP/TFTP protocol 5244diskboot- boot from IDE devicebootd - boot default, i.e., run 'bootcmd' 5245loads - load S-Record file over serial line 5246loadb - load binary file over serial line (kermit mode) 5247md - memory display 5248mm - memory modify (auto-incrementing) 5249nm - memory modify (constant address) 5250mw - memory write (fill) 5251cp - memory copy 5252cmp - memory compare 5253crc32 - checksum calculation 5254i2c - I2C sub-system 5255sspi - SPI utility commands 5256base - print or set address offset 5257printenv- print environment variables 5258setenv - set environment variables 5259saveenv - save environment variables to persistent storage 5260protect - enable or disable FLASH write protection 5261erase - erase FLASH memory 5262flinfo - print FLASH memory information 5263nand - NAND memory operations (see doc/README.nand) 5264bdinfo - print Board Info structure 5265iminfo - print header information for application image 5266coninfo - print console devices and informations 5267ide - IDE sub-system 5268loop - infinite loop on address range 5269loopw - infinite write loop on address range 5270mtest - simple RAM test 5271icache - enable or disable instruction cache 5272dcache - enable or disable data cache 5273reset - Perform RESET of the CPU 5274echo - echo args to console 5275version - print monitor version 5276help - print online help 5277? - alias for 'help' 5278 5279 5280Monitor Commands - Detailed Description: 5281======================================== 5282 5283TODO. 5284 5285For now: just type "help <command>". 5286 5287 5288Environment Variables: 5289====================== 5290 5291U-Boot supports user configuration using Environment Variables which 5292can be made persistent by saving to Flash memory. 5293 5294Environment Variables are set using "setenv", printed using 5295"printenv", and saved to Flash using "saveenv". Using "setenv" 5296without a value can be used to delete a variable from the 5297environment. As long as you don't save the environment you are 5298working with an in-memory copy. In case the Flash area containing the 5299environment is erased by accident, a default environment is provided. 5300 5301Some configuration options can be set using Environment Variables. 5302 5303List of environment variables (most likely not complete): 5304 5305 baudrate - see CONFIG_BAUDRATE 5306 5307 bootdelay - see CONFIG_BOOTDELAY 5308 5309 bootcmd - see CONFIG_BOOTCOMMAND 5310 5311 bootargs - Boot arguments when booting an RTOS image 5312 5313 bootfile - Name of the image to load with TFTP 5314 5315 bootm_low - Memory range available for image processing in the bootm 5316 command can be restricted. This variable is given as 5317 a hexadecimal number and defines lowest address allowed 5318 for use by the bootm command. See also "bootm_size" 5319 environment variable. Address defined by "bootm_low" is 5320 also the base of the initial memory mapping for the Linux 5321 kernel -- see the description of CONFIG_SYS_BOOTMAPSZ and 5322 bootm_mapsize. 5323 5324 bootm_mapsize - Size of the initial memory mapping for the Linux kernel. 5325 This variable is given as a hexadecimal number and it 5326 defines the size of the memory region starting at base 5327 address bootm_low that is accessible by the Linux kernel 5328 during early boot. If unset, CONFIG_SYS_BOOTMAPSZ is used 5329 as the default value if it is defined, and bootm_size is 5330 used otherwise. 5331 5332 bootm_size - Memory range available for image processing in the bootm 5333 command can be restricted. This variable is given as 5334 a hexadecimal number and defines the size of the region 5335 allowed for use by the bootm command. See also "bootm_low" 5336 environment variable. 5337 5338 updatefile - Location of the software update file on a TFTP server, used 5339 by the automatic software update feature. Please refer to 5340 documentation in doc/README.update for more details. 5341 5342 autoload - if set to "no" (any string beginning with 'n'), 5343 "bootp" will just load perform a lookup of the 5344 configuration from the BOOTP server, but not try to 5345 load any image using TFTP 5346 5347 autostart - if set to "yes", an image loaded using the "bootp", 5348 "rarpboot", "tftpboot" or "diskboot" commands will 5349 be automatically started (by internally calling 5350 "bootm") 5351 5352 If set to "no", a standalone image passed to the 5353 "bootm" command will be copied to the load address 5354 (and eventually uncompressed), but NOT be started. 5355 This can be used to load and uncompress arbitrary 5356 data. 5357 5358 fdt_high - if set this restricts the maximum address that the 5359 flattened device tree will be copied into upon boot. 5360 For example, if you have a system with 1 GB memory 5361 at physical address 0x10000000, while Linux kernel 5362 only recognizes the first 704 MB as low memory, you 5363 may need to set fdt_high as 0x3C000000 to have the 5364 device tree blob be copied to the maximum address 5365 of the 704 MB low memory, so that Linux kernel can 5366 access it during the boot procedure. 5367 5368 If this is set to the special value 0xFFFFFFFF then 5369 the fdt will not be copied at all on boot. For this 5370 to work it must reside in writable memory, have 5371 sufficient padding on the end of it for u-boot to 5372 add the information it needs into it, and the memory 5373 must be accessible by the kernel. 5374 5375 fdtcontroladdr- if set this is the address of the control flattened 5376 device tree used by U-Boot when CONFIG_OF_CONTROL is 5377 defined. 5378 5379 i2cfast - (PPC405GP|PPC405EP only) 5380 if set to 'y' configures Linux I2C driver for fast 5381 mode (400kHZ). This environment variable is used in 5382 initialization code. So, for changes to be effective 5383 it must be saved and board must be reset. 5384 5385 initrd_high - restrict positioning of initrd images: 5386 If this variable is not set, initrd images will be 5387 copied to the highest possible address in RAM; this 5388 is usually what you want since it allows for 5389 maximum initrd size. If for some reason you want to 5390 make sure that the initrd image is loaded below the 5391 CONFIG_SYS_BOOTMAPSZ limit, you can set this environment 5392 variable to a value of "no" or "off" or "0". 5393 Alternatively, you can set it to a maximum upper 5394 address to use (U-Boot will still check that it 5395 does not overwrite the U-Boot stack and data). 5396 5397 For instance, when you have a system with 16 MB 5398 RAM, and want to reserve 4 MB from use by Linux, 5399 you can do this by adding "mem=12M" to the value of 5400 the "bootargs" variable. However, now you must make 5401 sure that the initrd image is placed in the first 5402 12 MB as well - this can be done with 5403 5404 setenv initrd_high 00c00000 5405 5406 If you set initrd_high to 0xFFFFFFFF, this is an 5407 indication to U-Boot that all addresses are legal 5408 for the Linux kernel, including addresses in flash 5409 memory. In this case U-Boot will NOT COPY the 5410 ramdisk at all. This may be useful to reduce the 5411 boot time on your system, but requires that this 5412 feature is supported by your Linux kernel. 5413 5414 ipaddr - IP address; needed for tftpboot command 5415 5416 loadaddr - Default load address for commands like "bootp", 5417 "rarpboot", "tftpboot", "loadb" or "diskboot" 5418 5419 loads_echo - see CONFIG_LOADS_ECHO 5420 5421 serverip - TFTP server IP address; needed for tftpboot command 5422 5423 bootretry - see CONFIG_BOOT_RETRY_TIME 5424 5425 bootdelaykey - see CONFIG_AUTOBOOT_DELAY_STR 5426 5427 bootstopkey - see CONFIG_AUTOBOOT_STOP_STR 5428 5429 ethprime - controls which interface is used first. 5430 5431 ethact - controls which interface is currently active. 5432 For example you can do the following 5433 5434 => setenv ethact FEC 5435 => ping 192.168.0.1 # traffic sent on FEC 5436 => setenv ethact SCC 5437 => ping 10.0.0.1 # traffic sent on SCC 5438 5439 ethrotate - When set to "no" U-Boot does not go through all 5440 available network interfaces. 5441 It just stays at the currently selected interface. 5442 5443 netretry - When set to "no" each network operation will 5444 either succeed or fail without retrying. 5445 When set to "once" the network operation will 5446 fail when all the available network interfaces 5447 are tried once without success. 5448 Useful on scripts which control the retry operation 5449 themselves. 5450 5451 npe_ucode - set load address for the NPE microcode 5452 5453 silent_linux - If set then Linux will be told to boot silently, by 5454 changing the console to be empty. If "yes" it will be 5455 made silent. If "no" it will not be made silent. If 5456 unset, then it will be made silent if the U-Boot console 5457 is silent. 5458 5459 tftpsrcport - If this is set, the value is used for TFTP's 5460 UDP source port. 5461 5462 tftpdstport - If this is set, the value is used for TFTP's UDP 5463 destination port instead of the Well Know Port 69. 5464 5465 tftpblocksize - Block size to use for TFTP transfers; if not set, 5466 we use the TFTP server's default block size 5467 5468 tftptimeout - Retransmission timeout for TFTP packets (in milli- 5469 seconds, minimum value is 1000 = 1 second). Defines 5470 when a packet is considered to be lost so it has to 5471 be retransmitted. The default is 5000 = 5 seconds. 5472 Lowering this value may make downloads succeed 5473 faster in networks with high packet loss rates or 5474 with unreliable TFTP servers. 5475 5476 vlan - When set to a value < 4095 the traffic over 5477 Ethernet is encapsulated/received over 802.1q 5478 VLAN tagged frames. 5479 5480The following image location variables contain the location of images 5481used in booting. The "Image" column gives the role of the image and is 5482not an environment variable name. The other columns are environment 5483variable names. "File Name" gives the name of the file on a TFTP 5484server, "RAM Address" gives the location in RAM the image will be 5485loaded to, and "Flash Location" gives the image's address in NOR 5486flash or offset in NAND flash. 5487 5488*Note* - these variables don't have to be defined for all boards, some 5489boards currently use other variables for these purposes, and some 5490boards use these variables for other purposes. 5491 5492Image File Name RAM Address Flash Location 5493----- --------- ----------- -------------- 5494u-boot u-boot u-boot_addr_r u-boot_addr 5495Linux kernel bootfile kernel_addr_r kernel_addr 5496device tree blob fdtfile fdt_addr_r fdt_addr 5497ramdisk ramdiskfile ramdisk_addr_r ramdisk_addr 5498 5499The following environment variables may be used and automatically 5500updated by the network boot commands ("bootp" and "rarpboot"), 5501depending the information provided by your boot server: 5502 5503 bootfile - see above 5504 dnsip - IP address of your Domain Name Server 5505 dnsip2 - IP address of your secondary Domain Name Server 5506 gatewayip - IP address of the Gateway (Router) to use 5507 hostname - Target hostname 5508 ipaddr - see above 5509 netmask - Subnet Mask 5510 rootpath - Pathname of the root filesystem on the NFS server 5511 serverip - see above 5512 5513 5514There are two special Environment Variables: 5515 5516 serial# - contains hardware identification information such 5517 as type string and/or serial number 5518 ethaddr - Ethernet address 5519 5520These variables can be set only once (usually during manufacturing of 5521the board). U-Boot refuses to delete or overwrite these variables 5522once they have been set once. 5523 5524 5525Further special Environment Variables: 5526 5527 ver - Contains the U-Boot version string as printed 5528 with the "version" command. This variable is 5529 readonly (see CONFIG_VERSION_VARIABLE). 5530 5531 5532Please note that changes to some configuration parameters may take 5533only effect after the next boot (yes, that's just like Windoze :-). 5534 5535 5536Callback functions for environment variables: 5537--------------------------------------------- 5538 5539For some environment variables, the behavior of u-boot needs to change 5540when their values are changed. This functionality allows functions to 5541be associated with arbitrary variables. On creation, overwrite, or 5542deletion, the callback will provide the opportunity for some side 5543effect to happen or for the change to be rejected. 5544 5545The callbacks are named and associated with a function using the 5546U_BOOT_ENV_CALLBACK macro in your board or driver code. 5547 5548These callbacks are associated with variables in one of two ways. The 5549static list can be added to by defining CONFIG_ENV_CALLBACK_LIST_STATIC 5550in the board configuration to a string that defines a list of 5551associations. The list must be in the following format: 5552 5553 entry = variable_name[:callback_name] 5554 list = entry[,list] 5555 5556If the callback name is not specified, then the callback is deleted. 5557Spaces are also allowed anywhere in the list. 5558 5559Callbacks can also be associated by defining the ".callbacks" variable 5560with the same list format above. Any association in ".callbacks" will 5561override any association in the static list. You can define 5562CONFIG_ENV_CALLBACK_LIST_DEFAULT to a list (string) to define the 5563".callbacks" environment variable in the default or embedded environment. 5564 5565If CONFIG_REGEX is defined, the variable_name above is evaluated as a 5566regular expression. This allows multiple variables to be connected to 5567the same callback without explicitly listing them all out. 5568 5569 5570Command Line Parsing: 5571===================== 5572 5573There are two different command line parsers available with U-Boot: 5574the old "simple" one, and the much more powerful "hush" shell: 5575 5576Old, simple command line parser: 5577-------------------------------- 5578 5579- supports environment variables (through setenv / saveenv commands) 5580- several commands on one line, separated by ';' 5581- variable substitution using "... ${name} ..." syntax 5582- special characters ('$', ';') can be escaped by prefixing with '\', 5583 for example: 5584 setenv bootcmd bootm \${address} 5585- You can also escape text by enclosing in single apostrophes, for example: 5586 setenv addip 'setenv bootargs $bootargs ip=$ipaddr:$serverip:$gatewayip:$netmask:$hostname::off' 5587 5588Hush shell: 5589----------- 5590 5591- similar to Bourne shell, with control structures like 5592 if...then...else...fi, for...do...done; while...do...done, 5593 until...do...done, ... 5594- supports environment ("global") variables (through setenv / saveenv 5595 commands) and local shell variables (through standard shell syntax 5596 "name=value"); only environment variables can be used with "run" 5597 command 5598 5599General rules: 5600-------------- 5601 5602(1) If a command line (or an environment variable executed by a "run" 5603 command) contains several commands separated by semicolon, and 5604 one of these commands fails, then the remaining commands will be 5605 executed anyway. 5606 5607(2) If you execute several variables with one call to run (i. e. 5608 calling run with a list of variables as arguments), any failing 5609 command will cause "run" to terminate, i. e. the remaining 5610 variables are not executed. 5611 5612Note for Redundant Ethernet Interfaces: 5613======================================= 5614 5615Some boards come with redundant Ethernet interfaces; U-Boot supports 5616such configurations and is capable of automatic selection of a 5617"working" interface when needed. MAC assignment works as follows: 5618 5619Network interfaces are numbered eth0, eth1, eth2, ... Corresponding 5620MAC addresses can be stored in the environment as "ethaddr" (=>eth0), 5621"eth1addr" (=>eth1), "eth2addr", ... 5622 5623If the network interface stores some valid MAC address (for instance 5624in SROM), this is used as default address if there is NO correspon- 5625ding setting in the environment; if the corresponding environment 5626variable is set, this overrides the settings in the card; that means: 5627 5628o If the SROM has a valid MAC address, and there is no address in the 5629 environment, the SROM's address is used. 5630 5631o If there is no valid address in the SROM, and a definition in the 5632 environment exists, then the value from the environment variable is 5633 used. 5634 5635o If both the SROM and the environment contain a MAC address, and 5636 both addresses are the same, this MAC address is used. 5637 5638o If both the SROM and the environment contain a MAC address, and the 5639 addresses differ, the value from the environment is used and a 5640 warning is printed. 5641 5642o If neither SROM nor the environment contain a MAC address, an error 5643 is raised. If CONFIG_NET_RANDOM_ETHADDR is defined, then in this case 5644 a random, locally-assigned MAC is used. 5645 5646If Ethernet drivers implement the 'write_hwaddr' function, valid MAC addresses 5647will be programmed into hardware as part of the initialization process. This 5648may be skipped by setting the appropriate 'ethmacskip' environment variable. 5649The naming convention is as follows: 5650"ethmacskip" (=>eth0), "eth1macskip" (=>eth1) etc. 5651 5652Image Formats: 5653============== 5654 5655U-Boot is capable of booting (and performing other auxiliary operations on) 5656images in two formats: 5657 5658New uImage format (FIT) 5659----------------------- 5660 5661Flexible and powerful format based on Flattened Image Tree -- FIT (similar 5662to Flattened Device Tree). It allows the use of images with multiple 5663components (several kernels, ramdisks, etc.), with contents protected by 5664SHA1, MD5 or CRC32. More details are found in the doc/uImage.FIT directory. 5665 5666 5667Old uImage format 5668----------------- 5669 5670Old image format is based on binary files which can be basically anything, 5671preceded by a special header; see the definitions in include/image.h for 5672details; basically, the header defines the following image properties: 5673 5674* Target Operating System (Provisions for OpenBSD, NetBSD, FreeBSD, 5675 4.4BSD, Linux, SVR4, Esix, Solaris, Irix, SCO, Dell, NCR, VxWorks, 5676 LynxOS, pSOS, QNX, RTEMS, INTEGRITY; 5677 Currently supported: Linux, NetBSD, VxWorks, QNX, RTEMS, LynxOS, 5678 INTEGRITY). 5679* Target CPU Architecture (Provisions for Alpha, ARM, AVR32, Intel x86, 5680 IA64, MIPS, NDS32, Nios II, PowerPC, IBM S390, SuperH, Sparc, Sparc 64 Bit; 5681 Currently supported: ARM, AVR32, Intel x86, MIPS, NDS32, Nios II, PowerPC). 5682* Compression Type (uncompressed, gzip, bzip2) 5683* Load Address 5684* Entry Point 5685* Image Name 5686* Image Timestamp 5687 5688The header is marked by a special Magic Number, and both the header 5689and the data portions of the image are secured against corruption by 5690CRC32 checksums. 5691 5692 5693Linux Support: 5694============== 5695 5696Although U-Boot should support any OS or standalone application 5697easily, the main focus has always been on Linux during the design of 5698U-Boot. 5699 5700U-Boot includes many features that so far have been part of some 5701special "boot loader" code within the Linux kernel. Also, any 5702"initrd" images to be used are no longer part of one big Linux image; 5703instead, kernel and "initrd" are separate images. This implementation 5704serves several purposes: 5705 5706- the same features can be used for other OS or standalone 5707 applications (for instance: using compressed images to reduce the 5708 Flash memory footprint) 5709 5710- it becomes much easier to port new Linux kernel versions because 5711 lots of low-level, hardware dependent stuff are done by U-Boot 5712 5713- the same Linux kernel image can now be used with different "initrd" 5714 images; of course this also means that different kernel images can 5715 be run with the same "initrd". This makes testing easier (you don't 5716 have to build a new "zImage.initrd" Linux image when you just 5717 change a file in your "initrd"). Also, a field-upgrade of the 5718 software is easier now. 5719 5720 5721Linux HOWTO: 5722============ 5723 5724Porting Linux to U-Boot based systems: 5725--------------------------------------- 5726 5727U-Boot cannot save you from doing all the necessary modifications to 5728configure the Linux device drivers for use with your target hardware 5729(no, we don't intend to provide a full virtual machine interface to 5730Linux :-). 5731 5732But now you can ignore ALL boot loader code (in arch/powerpc/mbxboot). 5733 5734Just make sure your machine specific header file (for instance 5735include/asm-ppc/tqm8xx.h) includes the same definition of the Board 5736Information structure as we define in include/asm-<arch>/u-boot.h, 5737and make sure that your definition of IMAP_ADDR uses the same value 5738as your U-Boot configuration in CONFIG_SYS_IMMR. 5739 5740Note that U-Boot now has a driver model, a unified model for drivers. 5741If you are adding a new driver, plumb it into driver model. If there 5742is no uclass available, you are encouraged to create one. See 5743doc/driver-model. 5744 5745 5746Configuring the Linux kernel: 5747----------------------------- 5748 5749No specific requirements for U-Boot. Make sure you have some root 5750device (initial ramdisk, NFS) for your target system. 5751 5752 5753Building a Linux Image: 5754----------------------- 5755 5756With U-Boot, "normal" build targets like "zImage" or "bzImage" are 5757not used. If you use recent kernel source, a new build target 5758"uImage" will exist which automatically builds an image usable by 5759U-Boot. Most older kernels also have support for a "pImage" target, 5760which was introduced for our predecessor project PPCBoot and uses a 5761100% compatible format. 5762 5763Example: 5764 5765 make TQM850L_defconfig 5766 make oldconfig 5767 make dep 5768 make uImage 5769 5770The "uImage" build target uses a special tool (in 'tools/mkimage') to 5771encapsulate a compressed Linux kernel image with header information, 5772CRC32 checksum etc. for use with U-Boot. This is what we are doing: 5773 5774* build a standard "vmlinux" kernel image (in ELF binary format): 5775 5776* convert the kernel into a raw binary image: 5777 5778 ${CROSS_COMPILE}-objcopy -O binary \ 5779 -R .note -R .comment \ 5780 -S vmlinux linux.bin 5781 5782* compress the binary image: 5783 5784 gzip -9 linux.bin 5785 5786* package compressed binary image for U-Boot: 5787 5788 mkimage -A ppc -O linux -T kernel -C gzip \ 5789 -a 0 -e 0 -n "Linux Kernel Image" \ 5790 -d linux.bin.gz uImage 5791 5792 5793The "mkimage" tool can also be used to create ramdisk images for use 5794with U-Boot, either separated from the Linux kernel image, or 5795combined into one file. "mkimage" encapsulates the images with a 64 5796byte header containing information about target architecture, 5797operating system, image type, compression method, entry points, time 5798stamp, CRC32 checksums, etc. 5799 5800"mkimage" can be called in two ways: to verify existing images and 5801print the header information, or to build new images. 5802 5803In the first form (with "-l" option) mkimage lists the information 5804contained in the header of an existing U-Boot image; this includes 5805checksum verification: 5806 5807 tools/mkimage -l image 5808 -l ==> list image header information 5809 5810The second form (with "-d" option) is used to build a U-Boot image 5811from a "data file" which is used as image payload: 5812 5813 tools/mkimage -A arch -O os -T type -C comp -a addr -e ep \ 5814 -n name -d data_file image 5815 -A ==> set architecture to 'arch' 5816 -O ==> set operating system to 'os' 5817 -T ==> set image type to 'type' 5818 -C ==> set compression type 'comp' 5819 -a ==> set load address to 'addr' (hex) 5820 -e ==> set entry point to 'ep' (hex) 5821 -n ==> set image name to 'name' 5822 -d ==> use image data from 'datafile' 5823 5824Right now, all Linux kernels for PowerPC systems use the same load 5825address (0x00000000), but the entry point address depends on the 5826kernel version: 5827 5828- 2.2.x kernels have the entry point at 0x0000000C, 5829- 2.3.x and later kernels have the entry point at 0x00000000. 5830 5831So a typical call to build a U-Boot image would read: 5832 5833 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \ 5834 > -A ppc -O linux -T kernel -C gzip -a 0 -e 0 \ 5835 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux.gz \ 5836 > examples/uImage.TQM850L 5837 Image Name: 2.4.4 kernel for TQM850L 5838 Created: Wed Jul 19 02:34:59 2000 5839 Image Type: PowerPC Linux Kernel Image (gzip compressed) 5840 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB 5841 Load Address: 0x00000000 5842 Entry Point: 0x00000000 5843 5844To verify the contents of the image (or check for corruption): 5845 5846 -> tools/mkimage -l examples/uImage.TQM850L 5847 Image Name: 2.4.4 kernel for TQM850L 5848 Created: Wed Jul 19 02:34:59 2000 5849 Image Type: PowerPC Linux Kernel Image (gzip compressed) 5850 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB 5851 Load Address: 0x00000000 5852 Entry Point: 0x00000000 5853 5854NOTE: for embedded systems where boot time is critical you can trade 5855speed for memory and install an UNCOMPRESSED image instead: this 5856needs more space in Flash, but boots much faster since it does not 5857need to be uncompressed: 5858 5859 -> gunzip /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux.gz 5860 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \ 5861 > -A ppc -O linux -T kernel -C none -a 0 -e 0 \ 5862 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux \ 5863 > examples/uImage.TQM850L-uncompressed 5864 Image Name: 2.4.4 kernel for TQM850L 5865 Created: Wed Jul 19 02:34:59 2000 5866 Image Type: PowerPC Linux Kernel Image (uncompressed) 5867 Data Size: 792160 Bytes = 773.59 kB = 0.76 MB 5868 Load Address: 0x00000000 5869 Entry Point: 0x00000000 5870 5871 5872Similar you can build U-Boot images from a 'ramdisk.image.gz' file 5873when your kernel is intended to use an initial ramdisk: 5874 5875 -> tools/mkimage -n 'Simple Ramdisk Image' \ 5876 > -A ppc -O linux -T ramdisk -C gzip \ 5877 > -d /LinuxPPC/images/SIMPLE-ramdisk.image.gz examples/simple-initrd 5878 Image Name: Simple Ramdisk Image 5879 Created: Wed Jan 12 14:01:50 2000 5880 Image Type: PowerPC Linux RAMDisk Image (gzip compressed) 5881 Data Size: 566530 Bytes = 553.25 kB = 0.54 MB 5882 Load Address: 0x00000000 5883 Entry Point: 0x00000000 5884 5885The "dumpimage" is a tool to disassemble images built by mkimage. Its "-i" 5886option performs the converse operation of the mkimage's second form (the "-d" 5887option). Given an image built by mkimage, the dumpimage extracts a "data file" 5888from the image: 5889 5890 tools/dumpimage -i image -T type -p position data_file 5891 -i ==> extract from the 'image' a specific 'data_file' 5892 -T ==> set image type to 'type' 5893 -p ==> 'position' (starting at 0) of the 'data_file' inside the 'image' 5894 5895 5896Installing a Linux Image: 5897------------------------- 5898 5899To downloading a U-Boot image over the serial (console) interface, 5900you must convert the image to S-Record format: 5901 5902 objcopy -I binary -O srec examples/image examples/image.srec 5903 5904The 'objcopy' does not understand the information in the U-Boot 5905image header, so the resulting S-Record file will be relative to 5906address 0x00000000. To load it to a given address, you need to 5907specify the target address as 'offset' parameter with the 'loads' 5908command. 5909 5910Example: install the image to address 0x40100000 (which on the 5911TQM8xxL is in the first Flash bank): 5912 5913 => erase 40100000 401FFFFF 5914 5915 .......... done 5916 Erased 8 sectors 5917 5918 => loads 40100000 5919 ## Ready for S-Record download ... 5920 ~>examples/image.srec 5921 1 2 3 4 5 6 7 8 9 10 11 12 13 ... 5922 ... 5923 15989 15990 15991 15992 5924 [file transfer complete] 5925 [connected] 5926 ## Start Addr = 0x00000000 5927 5928 5929You can check the success of the download using the 'iminfo' command; 5930this includes a checksum verification so you can be sure no data 5931corruption happened: 5932 5933 => imi 40100000 5934 5935 ## Checking Image at 40100000 ... 5936 Image Name: 2.2.13 for initrd on TQM850L 5937 Image Type: PowerPC Linux Kernel Image (gzip compressed) 5938 Data Size: 335725 Bytes = 327 kB = 0 MB 5939 Load Address: 00000000 5940 Entry Point: 0000000c 5941 Verifying Checksum ... OK 5942 5943 5944Boot Linux: 5945----------- 5946 5947The "bootm" command is used to boot an application that is stored in 5948memory (RAM or Flash). In case of a Linux kernel image, the contents 5949of the "bootargs" environment variable is passed to the kernel as 5950parameters. You can check and modify this variable using the 5951"printenv" and "setenv" commands: 5952 5953 5954 => printenv bootargs 5955 bootargs=root=/dev/ram 5956 5957 => setenv bootargs root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2 5958 5959 => printenv bootargs 5960 bootargs=root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2 5961 5962 => bootm 40020000 5963 ## Booting Linux kernel at 40020000 ... 5964 Image Name: 2.2.13 for NFS on TQM850L 5965 Image Type: PowerPC Linux Kernel Image (gzip compressed) 5966 Data Size: 381681 Bytes = 372 kB = 0 MB 5967 Load Address: 00000000 5968 Entry Point: 0000000c 5969 Verifying Checksum ... OK 5970 Uncompressing Kernel Image ... OK 5971 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 5972 Boot arguments: root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2 5973 time_init: decrementer frequency = 187500000/60 5974 Calibrating delay loop... 49.77 BogoMIPS 5975 Memory: 15208k available (700k kernel code, 444k data, 32k init) [c0000000,c1000000] 5976 ... 5977 5978If you want to boot a Linux kernel with initial RAM disk, you pass 5979the memory addresses of both the kernel and the initrd image (PPBCOOT 5980format!) to the "bootm" command: 5981 5982 => imi 40100000 40200000 5983 5984 ## Checking Image at 40100000 ... 5985 Image Name: 2.2.13 for initrd on TQM850L 5986 Image Type: PowerPC Linux Kernel Image (gzip compressed) 5987 Data Size: 335725 Bytes = 327 kB = 0 MB 5988 Load Address: 00000000 5989 Entry Point: 0000000c 5990 Verifying Checksum ... OK 5991 5992 ## Checking Image at 40200000 ... 5993 Image Name: Simple Ramdisk Image 5994 Image Type: PowerPC Linux RAMDisk Image (gzip compressed) 5995 Data Size: 566530 Bytes = 553 kB = 0 MB 5996 Load Address: 00000000 5997 Entry Point: 00000000 5998 Verifying Checksum ... OK 5999 6000 => bootm 40100000 40200000 6001 ## Booting Linux kernel at 40100000 ... 6002 Image Name: 2.2.13 for initrd on TQM850L 6003 Image Type: PowerPC Linux Kernel Image (gzip compressed) 6004 Data Size: 335725 Bytes = 327 kB = 0 MB 6005 Load Address: 00000000 6006 Entry Point: 0000000c 6007 Verifying Checksum ... OK 6008 Uncompressing Kernel Image ... OK 6009 ## Loading RAMDisk Image at 40200000 ... 6010 Image Name: Simple Ramdisk Image 6011 Image Type: PowerPC Linux RAMDisk Image (gzip compressed) 6012 Data Size: 566530 Bytes = 553 kB = 0 MB 6013 Load Address: 00000000 6014 Entry Point: 00000000 6015 Verifying Checksum ... OK 6016 Loading Ramdisk ... OK 6017 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 6018 Boot arguments: root=/dev/ram 6019 time_init: decrementer frequency = 187500000/60 6020 Calibrating delay loop... 49.77 BogoMIPS 6021 ... 6022 RAMDISK: Compressed image found at block 0 6023 VFS: Mounted root (ext2 filesystem). 6024 6025 bash# 6026 6027Boot Linux and pass a flat device tree: 6028----------- 6029 6030First, U-Boot must be compiled with the appropriate defines. See the section 6031titled "Linux Kernel Interface" above for a more in depth explanation. The 6032following is an example of how to start a kernel and pass an updated 6033flat device tree: 6034 6035=> print oftaddr 6036oftaddr=0x300000 6037=> print oft 6038oft=oftrees/mpc8540ads.dtb 6039=> tftp $oftaddr $oft 6040Speed: 1000, full duplex 6041Using TSEC0 device 6042TFTP from server 192.168.1.1; our IP address is 192.168.1.101 6043Filename 'oftrees/mpc8540ads.dtb'. 6044Load address: 0x300000 6045Loading: # 6046done 6047Bytes transferred = 4106 (100a hex) 6048=> tftp $loadaddr $bootfile 6049Speed: 1000, full duplex 6050Using TSEC0 device 6051TFTP from server 192.168.1.1; our IP address is 192.168.1.2 6052Filename 'uImage'. 6053Load address: 0x200000 6054Loading:############ 6055done 6056Bytes transferred = 1029407 (fb51f hex) 6057=> print loadaddr 6058loadaddr=200000 6059=> print oftaddr 6060oftaddr=0x300000 6061=> bootm $loadaddr - $oftaddr 6062## Booting image at 00200000 ... 6063 Image Name: Linux-2.6.17-dirty 6064 Image Type: PowerPC Linux Kernel Image (gzip compressed) 6065 Data Size: 1029343 Bytes = 1005.2 kB 6066 Load Address: 00000000 6067 Entry Point: 00000000 6068 Verifying Checksum ... OK 6069 Uncompressing Kernel Image ... OK 6070Booting using flat device tree at 0x300000 6071Using MPC85xx ADS machine description 6072Memory CAM mapping: CAM0=256Mb, CAM1=256Mb, CAM2=0Mb residual: 0Mb 6073[snip] 6074 6075 6076More About U-Boot Image Types: 6077------------------------------ 6078 6079U-Boot supports the following image types: 6080 6081 "Standalone Programs" are directly runnable in the environment 6082 provided by U-Boot; it is expected that (if they behave 6083 well) you can continue to work in U-Boot after return from 6084 the Standalone Program. 6085 "OS Kernel Images" are usually images of some Embedded OS which 6086 will take over control completely. Usually these programs 6087 will install their own set of exception handlers, device 6088 drivers, set up the MMU, etc. - this means, that you cannot 6089 expect to re-enter U-Boot except by resetting the CPU. 6090 "RAMDisk Images" are more or less just data blocks, and their 6091 parameters (address, size) are passed to an OS kernel that is 6092 being started. 6093 "Multi-File Images" contain several images, typically an OS 6094 (Linux) kernel image and one or more data images like 6095 RAMDisks. This construct is useful for instance when you want 6096 to boot over the network using BOOTP etc., where the boot 6097 server provides just a single image file, but you want to get 6098 for instance an OS kernel and a RAMDisk image. 6099 6100 "Multi-File Images" start with a list of image sizes, each 6101 image size (in bytes) specified by an "uint32_t" in network 6102 byte order. This list is terminated by an "(uint32_t)0". 6103 Immediately after the terminating 0 follow the images, one by 6104 one, all aligned on "uint32_t" boundaries (size rounded up to 6105 a multiple of 4 bytes). 6106 6107 "Firmware Images" are binary images containing firmware (like 6108 U-Boot or FPGA images) which usually will be programmed to 6109 flash memory. 6110 6111 "Script files" are command sequences that will be executed by 6112 U-Boot's command interpreter; this feature is especially 6113 useful when you configure U-Boot to use a real shell (hush) 6114 as command interpreter. 6115 6116Booting the Linux zImage: 6117------------------------- 6118 6119On some platforms, it's possible to boot Linux zImage. This is done 6120using the "bootz" command. The syntax of "bootz" command is the same 6121as the syntax of "bootm" command. 6122 6123Note, defining the CONFIG_SUPPORT_RAW_INITRD allows user to supply 6124kernel with raw initrd images. The syntax is slightly different, the 6125address of the initrd must be augmented by it's size, in the following 6126format: "<initrd addres>:<initrd size>". 6127 6128 6129Standalone HOWTO: 6130================= 6131 6132One of the features of U-Boot is that you can dynamically load and 6133run "standalone" applications, which can use some resources of 6134U-Boot like console I/O functions or interrupt services. 6135 6136Two simple examples are included with the sources: 6137 6138"Hello World" Demo: 6139------------------- 6140 6141'examples/hello_world.c' contains a small "Hello World" Demo 6142application; it is automatically compiled when you build U-Boot. 6143It's configured to run at address 0x00040004, so you can play with it 6144like that: 6145 6146 => loads 6147 ## Ready for S-Record download ... 6148 ~>examples/hello_world.srec 6149 1 2 3 4 5 6 7 8 9 10 11 ... 6150 [file transfer complete] 6151 [connected] 6152 ## Start Addr = 0x00040004 6153 6154 => go 40004 Hello World! This is a test. 6155 ## Starting application at 0x00040004 ... 6156 Hello World 6157 argc = 7 6158 argv[0] = "40004" 6159 argv[1] = "Hello" 6160 argv[2] = "World!" 6161 argv[3] = "This" 6162 argv[4] = "is" 6163 argv[5] = "a" 6164 argv[6] = "test." 6165 argv[7] = "<NULL>" 6166 Hit any key to exit ... 6167 6168 ## Application terminated, rc = 0x0 6169 6170Another example, which demonstrates how to register a CPM interrupt 6171handler with the U-Boot code, can be found in 'examples/timer.c'. 6172Here, a CPM timer is set up to generate an interrupt every second. 6173The interrupt service routine is trivial, just printing a '.' 6174character, but this is just a demo program. The application can be 6175controlled by the following keys: 6176 6177 ? - print current values og the CPM Timer registers 6178 b - enable interrupts and start timer 6179 e - stop timer and disable interrupts 6180 q - quit application 6181 6182 => loads 6183 ## Ready for S-Record download ... 6184 ~>examples/timer.srec 6185 1 2 3 4 5 6 7 8 9 10 11 ... 6186 [file transfer complete] 6187 [connected] 6188 ## Start Addr = 0x00040004 6189 6190 => go 40004 6191 ## Starting application at 0x00040004 ... 6192 TIMERS=0xfff00980 6193 Using timer 1 6194 tgcr @ 0xfff00980, tmr @ 0xfff00990, trr @ 0xfff00994, tcr @ 0xfff00998, tcn @ 0xfff0099c, ter @ 0xfff009b0 6195 6196Hit 'b': 6197 [q, b, e, ?] Set interval 1000000 us 6198 Enabling timer 6199Hit '?': 6200 [q, b, e, ?] ........ 6201 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0xef6, ter=0x0 6202Hit '?': 6203 [q, b, e, ?] . 6204 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x2ad4, ter=0x0 6205Hit '?': 6206 [q, b, e, ?] . 6207 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x1efc, ter=0x0 6208Hit '?': 6209 [q, b, e, ?] . 6210 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x169d, ter=0x0 6211Hit 'e': 6212 [q, b, e, ?] ...Stopping timer 6213Hit 'q': 6214 [q, b, e, ?] ## Application terminated, rc = 0x0 6215 6216 6217Minicom warning: 6218================ 6219 6220Over time, many people have reported problems when trying to use the 6221"minicom" terminal emulation program for serial download. I (wd) 6222consider minicom to be broken, and recommend not to use it. Under 6223Unix, I recommend to use C-Kermit for general purpose use (and 6224especially for kermit binary protocol download ("loadb" command), and 6225use "cu" for S-Record download ("loads" command). See 6226http://www.denx.de/wiki/view/DULG/SystemSetup#Section_4.3. 6227for help with kermit. 6228 6229 6230Nevertheless, if you absolutely want to use it try adding this 6231configuration to your "File transfer protocols" section: 6232 6233 Name Program Name U/D FullScr IO-Red. Multi 6234 X kermit /usr/bin/kermit -i -l %l -s Y U Y N N 6235 Y kermit /usr/bin/kermit -i -l %l -r N D Y N N 6236 6237 6238NetBSD Notes: 6239============= 6240 6241Starting at version 0.9.2, U-Boot supports NetBSD both as host 6242(build U-Boot) and target system (boots NetBSD/mpc8xx). 6243 6244Building requires a cross environment; it is known to work on 6245NetBSD/i386 with the cross-powerpc-netbsd-1.3 package (you will also 6246need gmake since the Makefiles are not compatible with BSD make). 6247Note that the cross-powerpc package does not install include files; 6248attempting to build U-Boot will fail because <machine/ansi.h> is 6249missing. This file has to be installed and patched manually: 6250 6251 # cd /usr/pkg/cross/powerpc-netbsd/include 6252 # mkdir powerpc 6253 # ln -s powerpc machine 6254 # cp /usr/src/sys/arch/powerpc/include/ansi.h powerpc/ansi.h 6255 # ${EDIT} powerpc/ansi.h ## must remove __va_list, _BSD_VA_LIST 6256 6257Native builds *don't* work due to incompatibilities between native 6258and U-Boot include files. 6259 6260Booting assumes that (the first part of) the image booted is a 6261stage-2 loader which in turn loads and then invokes the kernel 6262proper. Loader sources will eventually appear in the NetBSD source 6263tree (probably in sys/arc/mpc8xx/stand/u-boot_stage2/); in the 6264meantime, see ftp://ftp.denx.de/pub/u-boot/ppcboot_stage2.tar.gz 6265 6266 6267Implementation Internals: 6268========================= 6269 6270The following is not intended to be a complete description of every 6271implementation detail. However, it should help to understand the 6272inner workings of U-Boot and make it easier to port it to custom 6273hardware. 6274 6275 6276Initial Stack, Global Data: 6277--------------------------- 6278 6279The implementation of U-Boot is complicated by the fact that U-Boot 6280starts running out of ROM (flash memory), usually without access to 6281system RAM (because the memory controller is not initialized yet). 6282This means that we don't have writable Data or BSS segments, and BSS 6283is not initialized as zero. To be able to get a C environment working 6284at all, we have to allocate at least a minimal stack. Implementation 6285options for this are defined and restricted by the CPU used: Some CPU 6286models provide on-chip memory (like the IMMR area on MPC8xx and 6287MPC826x processors), on others (parts of) the data cache can be 6288locked as (mis-) used as memory, etc. 6289 6290 Chris Hallinan posted a good summary of these issues to the 6291 U-Boot mailing list: 6292 6293 Subject: RE: [U-Boot-Users] RE: More On Memory Bank x (nothingness)? 6294 From: "Chris Hallinan" <clh@net1plus.com> 6295 Date: Mon, 10 Feb 2003 16:43:46 -0500 (22:43 MET) 6296 ... 6297 6298 Correct me if I'm wrong, folks, but the way I understand it 6299 is this: Using DCACHE as initial RAM for Stack, etc, does not 6300 require any physical RAM backing up the cache. The cleverness 6301 is that the cache is being used as a temporary supply of 6302 necessary storage before the SDRAM controller is setup. It's 6303 beyond the scope of this list to explain the details, but you 6304 can see how this works by studying the cache architecture and 6305 operation in the architecture and processor-specific manuals. 6306 6307 OCM is On Chip Memory, which I believe the 405GP has 4K. It 6308 is another option for the system designer to use as an 6309 initial stack/RAM area prior to SDRAM being available. Either 6310 option should work for you. Using CS 4 should be fine if your 6311 board designers haven't used it for something that would 6312 cause you grief during the initial boot! It is frequently not 6313 used. 6314 6315 CONFIG_SYS_INIT_RAM_ADDR should be somewhere that won't interfere 6316 with your processor/board/system design. The default value 6317 you will find in any recent u-boot distribution in 6318 walnut.h should work for you. I'd set it to a value larger 6319 than your SDRAM module. If you have a 64MB SDRAM module, set 6320 it above 400_0000. Just make sure your board has no resources 6321 that are supposed to respond to that address! That code in 6322 start.S has been around a while and should work as is when 6323 you get the config right. 6324 6325 -Chris Hallinan 6326 DS4.COM, Inc. 6327 6328It is essential to remember this, since it has some impact on the C 6329code for the initialization procedures: 6330 6331* Initialized global data (data segment) is read-only. Do not attempt 6332 to write it. 6333 6334* Do not use any uninitialized global data (or implicitly initialized 6335 as zero data - BSS segment) at all - this is undefined, initiali- 6336 zation is performed later (when relocating to RAM). 6337 6338* Stack space is very limited. Avoid big data buffers or things like 6339 that. 6340 6341Having only the stack as writable memory limits means we cannot use 6342normal global data to share information between the code. But it 6343turned out that the implementation of U-Boot can be greatly 6344simplified by making a global data structure (gd_t) available to all 6345functions. We could pass a pointer to this data as argument to _all_ 6346functions, but this would bloat the code. Instead we use a feature of 6347the GCC compiler (Global Register Variables) to share the data: we 6348place a pointer (gd) to the global data into a register which we 6349reserve for this purpose. 6350 6351When choosing a register for such a purpose we are restricted by the 6352relevant (E)ABI specifications for the current architecture, and by 6353GCC's implementation. 6354 6355For PowerPC, the following registers have specific use: 6356 R1: stack pointer 6357 R2: reserved for system use 6358 R3-R4: parameter passing and return values 6359 R5-R10: parameter passing 6360 R13: small data area pointer 6361 R30: GOT pointer 6362 R31: frame pointer 6363 6364 (U-Boot also uses R12 as internal GOT pointer. r12 6365 is a volatile register so r12 needs to be reset when 6366 going back and forth between asm and C) 6367 6368 ==> U-Boot will use R2 to hold a pointer to the global data 6369 6370 Note: on PPC, we could use a static initializer (since the 6371 address of the global data structure is known at compile time), 6372 but it turned out that reserving a register results in somewhat 6373 smaller code - although the code savings are not that big (on 6374 average for all boards 752 bytes for the whole U-Boot image, 6375 624 text + 127 data). 6376 6377On Blackfin, the normal C ABI (except for P3) is followed as documented here: 6378 http://docs.blackfin.uclinux.org/doku.php?id=application_binary_interface 6379 6380 ==> U-Boot will use P3 to hold a pointer to the global data 6381 6382On ARM, the following registers are used: 6383 6384 R0: function argument word/integer result 6385 R1-R3: function argument word 6386 R9: platform specific 6387 R10: stack limit (used only if stack checking is enabled) 6388 R11: argument (frame) pointer 6389 R12: temporary workspace 6390 R13: stack pointer 6391 R14: link register 6392 R15: program counter 6393 6394 ==> U-Boot will use R9 to hold a pointer to the global data 6395 6396 Note: on ARM, only R_ARM_RELATIVE relocations are supported. 6397 6398On Nios II, the ABI is documented here: 6399 http://www.altera.com/literature/hb/nios2/n2cpu_nii51016.pdf 6400 6401 ==> U-Boot will use gp to hold a pointer to the global data 6402 6403 Note: on Nios II, we give "-G0" option to gcc and don't use gp 6404 to access small data sections, so gp is free. 6405 6406On NDS32, the following registers are used: 6407 6408 R0-R1: argument/return 6409 R2-R5: argument 6410 R15: temporary register for assembler 6411 R16: trampoline register 6412 R28: frame pointer (FP) 6413 R29: global pointer (GP) 6414 R30: link register (LP) 6415 R31: stack pointer (SP) 6416 PC: program counter (PC) 6417 6418 ==> U-Boot will use R10 to hold a pointer to the global data 6419 6420NOTE: DECLARE_GLOBAL_DATA_PTR must be used with file-global scope, 6421or current versions of GCC may "optimize" the code too much. 6422 6423Memory Management: 6424------------------ 6425 6426U-Boot runs in system state and uses physical addresses, i.e. the 6427MMU is not used either for address mapping nor for memory protection. 6428 6429The available memory is mapped to fixed addresses using the memory 6430controller. In this process, a contiguous block is formed for each 6431memory type (Flash, SDRAM, SRAM), even when it consists of several 6432physical memory banks. 6433 6434U-Boot is installed in the first 128 kB of the first Flash bank (on 6435TQM8xxL modules this is the range 0x40000000 ... 0x4001FFFF). After 6436booting and sizing and initializing DRAM, the code relocates itself 6437to the upper end of DRAM. Immediately below the U-Boot code some 6438memory is reserved for use by malloc() [see CONFIG_SYS_MALLOC_LEN 6439configuration setting]. Below that, a structure with global Board 6440Info data is placed, followed by the stack (growing downward). 6441 6442Additionally, some exception handler code is copied to the low 8 kB 6443of DRAM (0x00000000 ... 0x00001FFF). 6444 6445So a typical memory configuration with 16 MB of DRAM could look like 6446this: 6447 6448 0x0000 0000 Exception Vector code 6449 : 6450 0x0000 1FFF 6451 0x0000 2000 Free for Application Use 6452 : 6453 : 6454 6455 : 6456 : 6457 0x00FB FF20 Monitor Stack (Growing downward) 6458 0x00FB FFAC Board Info Data and permanent copy of global data 6459 0x00FC 0000 Malloc Arena 6460 : 6461 0x00FD FFFF 6462 0x00FE 0000 RAM Copy of Monitor Code 6463 ... eventually: LCD or video framebuffer 6464 ... eventually: pRAM (Protected RAM - unchanged by reset) 6465 0x00FF FFFF [End of RAM] 6466 6467 6468System Initialization: 6469---------------------- 6470 6471In the reset configuration, U-Boot starts at the reset entry point 6472(on most PowerPC systems at address 0x00000100). Because of the reset 6473configuration for CS0# this is a mirror of the on board Flash memory. 6474To be able to re-map memory U-Boot then jumps to its link address. 6475To be able to implement the initialization code in C, a (small!) 6476initial stack is set up in the internal Dual Ported RAM (in case CPUs 6477which provide such a feature like MPC8xx or MPC8260), or in a locked 6478part of the data cache. After that, U-Boot initializes the CPU core, 6479the caches and the SIU. 6480 6481Next, all (potentially) available memory banks are mapped using a 6482preliminary mapping. For example, we put them on 512 MB boundaries 6483(multiples of 0x20000000: SDRAM on 0x00000000 and 0x20000000, Flash 6484on 0x40000000 and 0x60000000, SRAM on 0x80000000). Then UPM A is 6485programmed for SDRAM access. Using the temporary configuration, a 6486simple memory test is run that determines the size of the SDRAM 6487banks. 6488 6489When there is more than one SDRAM bank, and the banks are of 6490different size, the largest is mapped first. For equal size, the first 6491bank (CS2#) is mapped first. The first mapping is always for address 64920x00000000, with any additional banks following immediately to create 6493contiguous memory starting from 0. 6494 6495Then, the monitor installs itself at the upper end of the SDRAM area 6496and allocates memory for use by malloc() and for the global Board 6497Info data; also, the exception vector code is copied to the low RAM 6498pages, and the final stack is set up. 6499 6500Only after this relocation will you have a "normal" C environment; 6501until that you are restricted in several ways, mostly because you are 6502running from ROM, and because the code will have to be relocated to a 6503new address in RAM. 6504 6505 6506U-Boot Porting Guide: 6507---------------------- 6508 6509[Based on messages by Jerry Van Baren in the U-Boot-Users mailing 6510list, October 2002] 6511 6512 6513int main(int argc, char *argv[]) 6514{ 6515 sighandler_t no_more_time; 6516 6517 signal(SIGALRM, no_more_time); 6518 alarm(PROJECT_DEADLINE - toSec (3 * WEEK)); 6519 6520 if (available_money > available_manpower) { 6521 Pay consultant to port U-Boot; 6522 return 0; 6523 } 6524 6525 Download latest U-Boot source; 6526 6527 Subscribe to u-boot mailing list; 6528 6529 if (clueless) 6530 email("Hi, I am new to U-Boot, how do I get started?"); 6531 6532 while (learning) { 6533 Read the README file in the top level directory; 6534 Read http://www.denx.de/twiki/bin/view/DULG/Manual; 6535 Read applicable doc/*.README; 6536 Read the source, Luke; 6537 /* find . -name "*.[chS]" | xargs grep -i <keyword> */ 6538 } 6539 6540 if (available_money > toLocalCurrency ($2500)) 6541 Buy a BDI3000; 6542 else 6543 Add a lot of aggravation and time; 6544 6545 if (a similar board exists) { /* hopefully... */ 6546 cp -a board/<similar> board/<myboard> 6547 cp include/configs/<similar>.h include/configs/<myboard>.h 6548 } else { 6549 Create your own board support subdirectory; 6550 Create your own board include/configs/<myboard>.h file; 6551 } 6552 Edit new board/<myboard> files 6553 Edit new include/configs/<myboard>.h 6554 6555 while (!accepted) { 6556 while (!running) { 6557 do { 6558 Add / modify source code; 6559 } until (compiles); 6560 Debug; 6561 if (clueless) 6562 email("Hi, I am having problems..."); 6563 } 6564 Send patch file to the U-Boot email list; 6565 if (reasonable critiques) 6566 Incorporate improvements from email list code review; 6567 else 6568 Defend code as written; 6569 } 6570 6571 return 0; 6572} 6573 6574void no_more_time (int sig) 6575{ 6576 hire_a_guru(); 6577} 6578 6579 6580Coding Standards: 6581----------------- 6582 6583All contributions to U-Boot should conform to the Linux kernel 6584coding style; see the file "Documentation/CodingStyle" and the script 6585"scripts/Lindent" in your Linux kernel source directory. 6586 6587Source files originating from a different project (for example the 6588MTD subsystem) are generally exempt from these guidelines and are not 6589reformatted to ease subsequent migration to newer versions of those 6590sources. 6591 6592Please note that U-Boot is implemented in C (and to some small parts in 6593Assembler); no C++ is used, so please do not use C++ style comments (//) 6594in your code. 6595 6596Please also stick to the following formatting rules: 6597- remove any trailing white space 6598- use TAB characters for indentation and vertical alignment, not spaces 6599- make sure NOT to use DOS '\r\n' line feeds 6600- do not add more than 2 consecutive empty lines to source files 6601- do not add trailing empty lines to source files 6602 6603Submissions which do not conform to the standards may be returned 6604with a request to reformat the changes. 6605 6606 6607Submitting Patches: 6608------------------- 6609 6610Since the number of patches for U-Boot is growing, we need to 6611establish some rules. Submissions which do not conform to these rules 6612may be rejected, even when they contain important and valuable stuff. 6613 6614Please see http://www.denx.de/wiki/U-Boot/Patches for details. 6615 6616Patches shall be sent to the u-boot mailing list <u-boot@lists.denx.de>; 6617see http://lists.denx.de/mailman/listinfo/u-boot 6618 6619When you send a patch, please include the following information with 6620it: 6621 6622* For bug fixes: a description of the bug and how your patch fixes 6623 this bug. Please try to include a way of demonstrating that the 6624 patch actually fixes something. 6625 6626* For new features: a description of the feature and your 6627 implementation. 6628 6629* A CHANGELOG entry as plaintext (separate from the patch) 6630 6631* For major contributions, your entry to the CREDITS file 6632 6633* When you add support for a new board, don't forget to add a 6634 maintainer e-mail address to the boards.cfg file, too. 6635 6636* If your patch adds new configuration options, don't forget to 6637 document these in the README file. 6638 6639* The patch itself. If you are using git (which is *strongly* 6640 recommended) you can easily generate the patch using the 6641 "git format-patch". If you then use "git send-email" to send it to 6642 the U-Boot mailing list, you will avoid most of the common problems 6643 with some other mail clients. 6644 6645 If you cannot use git, use "diff -purN OLD NEW". If your version of 6646 diff does not support these options, then get the latest version of 6647 GNU diff. 6648 6649 The current directory when running this command shall be the parent 6650 directory of the U-Boot source tree (i. e. please make sure that 6651 your patch includes sufficient directory information for the 6652 affected files). 6653 6654 We prefer patches as plain text. MIME attachments are discouraged, 6655 and compressed attachments must not be used. 6656 6657* If one logical set of modifications affects or creates several 6658 files, all these changes shall be submitted in a SINGLE patch file. 6659 6660* Changesets that contain different, unrelated modifications shall be 6661 submitted as SEPARATE patches, one patch per changeset. 6662 6663 6664Notes: 6665 6666* Before sending the patch, run the MAKEALL script on your patched 6667 source tree and make sure that no errors or warnings are reported 6668 for any of the boards. 6669 6670* Keep your modifications to the necessary minimum: A patch 6671 containing several unrelated changes or arbitrary reformats will be 6672 returned with a request to re-formatting / split it. 6673 6674* If you modify existing code, make sure that your new code does not 6675 add to the memory footprint of the code ;-) Small is beautiful! 6676 When adding new features, these should compile conditionally only 6677 (using #ifdef), and the resulting code with the new feature 6678 disabled must not need more memory than the old code without your 6679 modification. 6680 6681* Remember that there is a size limit of 100 kB per message on the 6682 u-boot mailing list. Bigger patches will be moderated. If they are 6683 reasonable and not too big, they will be acknowledged. But patches 6684 bigger than the size limit should be avoided. 6685