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 NOTE: The following can be machine specific errata. These 694 do have ability to provide rudimentary version and machine 695 specific checks, but expect no product checks. 696 CONFIG_ARM_ERRATA_430973 697 CONFIG_ARM_ERRATA_454179 698 CONFIG_ARM_ERRATA_621766 699 CONFIG_ARM_ERRATA_798870 700 701- Tegra SoC options: 702 CONFIG_TEGRA_SUPPORT_NON_SECURE 703 704 Support executing U-Boot in non-secure (NS) mode. Certain 705 impossible actions will be skipped if the CPU is in NS mode, 706 such as ARM architectural timer initialization. 707 708- Linux Kernel Interface: 709 CONFIG_CLOCKS_IN_MHZ 710 711 U-Boot stores all clock information in Hz 712 internally. For binary compatibility with older Linux 713 kernels (which expect the clocks passed in the 714 bd_info data to be in MHz) the environment variable 715 "clocks_in_mhz" can be defined so that U-Boot 716 converts clock data to MHZ before passing it to the 717 Linux kernel. 718 When CONFIG_CLOCKS_IN_MHZ is defined, a definition of 719 "clocks_in_mhz=1" is automatically included in the 720 default environment. 721 722 CONFIG_MEMSIZE_IN_BYTES [relevant for MIPS only] 723 724 When transferring memsize parameter to Linux, some versions 725 expect it to be in bytes, others in MB. 726 Define CONFIG_MEMSIZE_IN_BYTES to make it in bytes. 727 728 CONFIG_OF_LIBFDT 729 730 New kernel versions are expecting firmware settings to be 731 passed using flattened device trees (based on open firmware 732 concepts). 733 734 CONFIG_OF_LIBFDT 735 * New libfdt-based support 736 * Adds the "fdt" command 737 * The bootm command automatically updates the fdt 738 739 OF_CPU - The proper name of the cpus node (only required for 740 MPC512X and MPC5xxx based boards). 741 OF_SOC - The proper name of the soc node (only required for 742 MPC512X and MPC5xxx based boards). 743 OF_TBCLK - The timebase frequency. 744 OF_STDOUT_PATH - The path to the console device 745 746 boards with QUICC Engines require OF_QE to set UCC MAC 747 addresses 748 749 CONFIG_OF_BOARD_SETUP 750 751 Board code has addition modification that it wants to make 752 to the flat device tree before handing it off to the kernel 753 754 CONFIG_OF_SYSTEM_SETUP 755 756 Other code has addition modification that it wants to make 757 to the flat device tree before handing it off to the kernel. 758 This causes ft_system_setup() to be called before booting 759 the kernel. 760 761 CONFIG_OF_BOOT_CPU 762 763 This define fills in the correct boot CPU in the boot 764 param header, the default value is zero if undefined. 765 766 CONFIG_OF_IDE_FIXUP 767 768 U-Boot can detect if an IDE device is present or not. 769 If not, and this new config option is activated, U-Boot 770 removes the ATA node from the DTS before booting Linux, 771 so the Linux IDE driver does not probe the device and 772 crash. This is needed for buggy hardware (uc101) where 773 no pull down resistor is connected to the signal IDE5V_DD7. 774 775 CONFIG_MACH_TYPE [relevant for ARM only][mandatory] 776 777 This setting is mandatory for all boards that have only one 778 machine type and must be used to specify the machine type 779 number as it appears in the ARM machine registry 780 (see http://www.arm.linux.org.uk/developer/machines/). 781 Only boards that have multiple machine types supported 782 in a single configuration file and the machine type is 783 runtime discoverable, do not have to use this setting. 784 785- vxWorks boot parameters: 786 787 bootvx constructs a valid bootline using the following 788 environments variables: bootfile, ipaddr, serverip, hostname. 789 It loads the vxWorks image pointed bootfile. 790 791 CONFIG_SYS_VXWORKS_BOOT_DEVICE - The vxworks device name 792 CONFIG_SYS_VXWORKS_MAC_PTR - Ethernet 6 byte MA -address 793 CONFIG_SYS_VXWORKS_SERVERNAME - Name of the server 794 CONFIG_SYS_VXWORKS_BOOT_ADDR - Address of boot parameters 795 796 CONFIG_SYS_VXWORKS_ADD_PARAMS 797 798 Add it at the end of the bootline. E.g "u=username pw=secret" 799 800 Note: If a "bootargs" environment is defined, it will overwride 801 the defaults discussed just above. 802 803- Cache Configuration: 804 CONFIG_SYS_ICACHE_OFF - Do not enable instruction cache in U-Boot 805 CONFIG_SYS_DCACHE_OFF - Do not enable data cache in U-Boot 806 CONFIG_SYS_L2CACHE_OFF- Do not enable L2 cache in U-Boot 807 808- Cache Configuration for ARM: 809 CONFIG_SYS_L2_PL310 - Enable support for ARM PL310 L2 cache 810 controller 811 CONFIG_SYS_PL310_BASE - Physical base address of PL310 812 controller register space 813 814- Serial Ports: 815 CONFIG_PL010_SERIAL 816 817 Define this if you want support for Amba PrimeCell PL010 UARTs. 818 819 CONFIG_PL011_SERIAL 820 821 Define this if you want support for Amba PrimeCell PL011 UARTs. 822 823 CONFIG_PL011_CLOCK 824 825 If you have Amba PrimeCell PL011 UARTs, set this variable to 826 the clock speed of the UARTs. 827 828 CONFIG_PL01x_PORTS 829 830 If you have Amba PrimeCell PL010 or PL011 UARTs on your board, 831 define this to a list of base addresses for each (supported) 832 port. See e.g. include/configs/versatile.h 833 834 CONFIG_PL011_SERIAL_RLCR 835 836 Some vendor versions of PL011 serial ports (e.g. ST-Ericsson U8500) 837 have separate receive and transmit line control registers. Set 838 this variable to initialize the extra register. 839 840 CONFIG_PL011_SERIAL_FLUSH_ON_INIT 841 842 On some platforms (e.g. U8500) U-Boot is loaded by a second stage 843 boot loader that has already initialized the UART. Define this 844 variable to flush the UART at init time. 845 846 CONFIG_SERIAL_HW_FLOW_CONTROL 847 848 Define this variable to enable hw flow control in serial driver. 849 Current user of this option is drivers/serial/nsl16550.c driver 850 851- Console Interface: 852 Depending on board, define exactly one serial port 853 (like CONFIG_8xx_CONS_SMC1, CONFIG_8xx_CONS_SMC2, 854 CONFIG_8xx_CONS_SCC1, ...), or switch off the serial 855 console by defining CONFIG_8xx_CONS_NONE 856 857 Note: if CONFIG_8xx_CONS_NONE is defined, the serial 858 port routines must be defined elsewhere 859 (i.e. serial_init(), serial_getc(), ...) 860 861 CONFIG_CFB_CONSOLE 862 Enables console device for a color framebuffer. Needs following 863 defines (cf. smiLynxEM, i8042) 864 VIDEO_FB_LITTLE_ENDIAN graphic memory organisation 865 (default big endian) 866 VIDEO_HW_RECTFILL graphic chip supports 867 rectangle fill 868 (cf. smiLynxEM) 869 VIDEO_HW_BITBLT graphic chip supports 870 bit-blit (cf. smiLynxEM) 871 VIDEO_VISIBLE_COLS visible pixel columns 872 (cols=pitch) 873 VIDEO_VISIBLE_ROWS visible pixel rows 874 VIDEO_PIXEL_SIZE bytes per pixel 875 VIDEO_DATA_FORMAT graphic data format 876 (0-5, cf. cfb_console.c) 877 VIDEO_FB_ADRS framebuffer address 878 VIDEO_KBD_INIT_FCT keyboard int fct 879 (i.e. i8042_kbd_init()) 880 VIDEO_TSTC_FCT test char fct 881 (i.e. i8042_tstc) 882 VIDEO_GETC_FCT get char fct 883 (i.e. i8042_getc) 884 CONFIG_CONSOLE_CURSOR cursor drawing on/off 885 (requires blink timer 886 cf. i8042.c) 887 CONFIG_SYS_CONSOLE_BLINK_COUNT blink interval (cf. i8042.c) 888 CONFIG_CONSOLE_TIME display time/date info in 889 upper right corner 890 (requires CONFIG_CMD_DATE) 891 CONFIG_VIDEO_LOGO display Linux logo in 892 upper left corner 893 CONFIG_VIDEO_BMP_LOGO use bmp_logo.h instead of 894 linux_logo.h for logo. 895 Requires CONFIG_VIDEO_LOGO 896 CONFIG_CONSOLE_EXTRA_INFO 897 additional board info beside 898 the logo 899 900 When CONFIG_CFB_CONSOLE_ANSI is defined, console will support 901 a limited number of ANSI escape sequences (cursor control, 902 erase functions and limited graphics rendition control). 903 904 When CONFIG_CFB_CONSOLE is defined, video console is 905 default i/o. Serial console can be forced with 906 environment 'console=serial'. 907 908 When CONFIG_SILENT_CONSOLE is defined, all console 909 messages (by U-Boot and Linux!) can be silenced with 910 the "silent" environment variable. See 911 doc/README.silent for more information. 912 913 CONFIG_SYS_CONSOLE_BG_COL: define the backgroundcolor, default 914 is 0x00. 915 CONFIG_SYS_CONSOLE_FG_COL: define the foregroundcolor, default 916 is 0xa0. 917 918- Console Baudrate: 919 CONFIG_BAUDRATE - in bps 920 Select one of the baudrates listed in 921 CONFIG_SYS_BAUDRATE_TABLE, see below. 922 CONFIG_SYS_BRGCLK_PRESCALE, baudrate prescale 923 924- Console Rx buffer length 925 With CONFIG_SYS_SMC_RXBUFLEN it is possible to define 926 the maximum receive buffer length for the SMC. 927 This option is actual only for 82xx and 8xx possible. 928 If using CONFIG_SYS_SMC_RXBUFLEN also CONFIG_SYS_MAXIDLE 929 must be defined, to setup the maximum idle timeout for 930 the SMC. 931 932- Pre-Console Buffer: 933 Prior to the console being initialised (i.e. serial UART 934 initialised etc) all console output is silently discarded. 935 Defining CONFIG_PRE_CONSOLE_BUFFER will cause U-Boot to 936 buffer any console messages prior to the console being 937 initialised to a buffer of size CONFIG_PRE_CON_BUF_SZ 938 bytes located at CONFIG_PRE_CON_BUF_ADDR. The buffer is 939 a circular buffer, so if more than CONFIG_PRE_CON_BUF_SZ 940 bytes are output before the console is initialised, the 941 earlier bytes are discarded. 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_AUTOBOOT_DELAY_STR2 970 CONFIG_AUTOBOOT_STOP_STR2 971 CONFIG_ZERO_BOOTDELAY_CHECK 972 CONFIG_RESET_TO_RETRY 973 974- Autoboot Command: 975 CONFIG_BOOTCOMMAND 976 Only needed when CONFIG_BOOTDELAY is enabled; 977 define a command string that is automatically executed 978 when no character is read on the console interface 979 within "Boot Delay" after reset. 980 981 CONFIG_BOOTARGS 982 This can be used to pass arguments to the bootm 983 command. The value of CONFIG_BOOTARGS goes into the 984 environment value "bootargs". 985 986 CONFIG_RAMBOOT and CONFIG_NFSBOOT 987 The value of these goes into the environment as 988 "ramboot" and "nfsboot" respectively, and can be used 989 as a convenience, when switching between booting from 990 RAM and NFS. 991 992- Bootcount: 993 CONFIG_BOOTCOUNT_LIMIT 994 Implements a mechanism for detecting a repeating reboot 995 cycle, see: 996 http://www.denx.de/wiki/view/DULG/UBootBootCountLimit 997 998 CONFIG_BOOTCOUNT_ENV 999 If no softreset save registers are found on the hardware 1000 "bootcount" is stored in the environment. To prevent a 1001 saveenv on all reboots, the environment variable 1002 "upgrade_available" is used. If "upgrade_available" is 1003 0, "bootcount" is always 0, if "upgrade_available" is 1004 1 "bootcount" is incremented in the environment. 1005 So the Userspace Applikation must set the "upgrade_available" 1006 and "bootcount" variable to 0, if a boot was successfully. 1007 1008- Pre-Boot Commands: 1009 CONFIG_PREBOOT 1010 1011 When this option is #defined, the existence of the 1012 environment variable "preboot" will be checked 1013 immediately before starting the CONFIG_BOOTDELAY 1014 countdown and/or running the auto-boot command resp. 1015 entering interactive mode. 1016 1017 This feature is especially useful when "preboot" is 1018 automatically generated or modified. For an example 1019 see the LWMON board specific code: here "preboot" is 1020 modified when the user holds down a certain 1021 combination of keys on the (special) keyboard when 1022 booting the systems 1023 1024- Serial Download Echo Mode: 1025 CONFIG_LOADS_ECHO 1026 If defined to 1, all characters received during a 1027 serial download (using the "loads" command) are 1028 echoed back. This might be needed by some terminal 1029 emulations (like "cu"), but may as well just take 1030 time on others. This setting #define's the initial 1031 value of the "loads_echo" environment variable. 1032 1033- Kgdb Serial Baudrate: (if CONFIG_CMD_KGDB is defined) 1034 CONFIG_KGDB_BAUDRATE 1035 Select one of the baudrates listed in 1036 CONFIG_SYS_BAUDRATE_TABLE, see below. 1037 1038- Monitor Functions: 1039 Monitor commands can be included or excluded 1040 from the build by using the #include files 1041 <config_cmd_all.h> and #undef'ing unwanted 1042 commands, or using <config_cmd_default.h> 1043 and augmenting with additional #define's 1044 for wanted commands. 1045 1046 The default command configuration includes all commands 1047 except those marked below with a "*". 1048 1049 CONFIG_CMD_AES AES 128 CBC encrypt/decrypt 1050 CONFIG_CMD_ASKENV * ask for env variable 1051 CONFIG_CMD_BDI bdinfo 1052 CONFIG_CMD_BEDBUG * Include BedBug Debugger 1053 CONFIG_CMD_BMP * BMP support 1054 CONFIG_CMD_BSP * Board specific commands 1055 CONFIG_CMD_BOOTD bootd 1056 CONFIG_CMD_BOOTI * ARM64 Linux kernel Image support 1057 CONFIG_CMD_CACHE * icache, dcache 1058 CONFIG_CMD_CLK * clock command support 1059 CONFIG_CMD_CONSOLE coninfo 1060 CONFIG_CMD_CRC32 * crc32 1061 CONFIG_CMD_DATE * support for RTC, date/time... 1062 CONFIG_CMD_DHCP * DHCP support 1063 CONFIG_CMD_DIAG * Diagnostics 1064 CONFIG_CMD_DS4510 * ds4510 I2C gpio commands 1065 CONFIG_CMD_DS4510_INFO * ds4510 I2C info command 1066 CONFIG_CMD_DS4510_MEM * ds4510 I2C eeprom/sram commansd 1067 CONFIG_CMD_DS4510_RST * ds4510 I2C rst command 1068 CONFIG_CMD_DTT * Digital Therm and Thermostat 1069 CONFIG_CMD_ECHO echo arguments 1070 CONFIG_CMD_EDITENV edit env variable 1071 CONFIG_CMD_EEPROM * EEPROM read/write support 1072 CONFIG_CMD_ELF * bootelf, bootvx 1073 CONFIG_CMD_ENV_CALLBACK * display details about env callbacks 1074 CONFIG_CMD_ENV_FLAGS * display details about env flags 1075 CONFIG_CMD_ENV_EXISTS * check existence of env variable 1076 CONFIG_CMD_EXPORTENV * export the environment 1077 CONFIG_CMD_EXT2 * ext2 command support 1078 CONFIG_CMD_EXT4 * ext4 command support 1079 CONFIG_CMD_FS_GENERIC * filesystem commands (e.g. load, ls) 1080 that work for multiple fs types 1081 CONFIG_CMD_FS_UUID * Look up a filesystem UUID 1082 CONFIG_CMD_SAVEENV saveenv 1083 CONFIG_CMD_FDC * Floppy Disk Support 1084 CONFIG_CMD_FAT * FAT command support 1085 CONFIG_CMD_FLASH flinfo, erase, protect 1086 CONFIG_CMD_FPGA FPGA device initialization support 1087 CONFIG_CMD_FUSE * Device fuse support 1088 CONFIG_CMD_GETTIME * Get time since boot 1089 CONFIG_CMD_GO * the 'go' command (exec code) 1090 CONFIG_CMD_GREPENV * search environment 1091 CONFIG_CMD_HASH * calculate hash / digest 1092 CONFIG_CMD_HWFLOW * RTS/CTS hw flow control 1093 CONFIG_CMD_I2C * I2C serial bus support 1094 CONFIG_CMD_IDE * IDE harddisk support 1095 CONFIG_CMD_IMI iminfo 1096 CONFIG_CMD_IMLS List all images found in NOR flash 1097 CONFIG_CMD_IMLS_NAND * List all images found in NAND flash 1098 CONFIG_CMD_IMMAP * IMMR dump support 1099 CONFIG_CMD_IOTRACE * I/O tracing for debugging 1100 CONFIG_CMD_IMPORTENV * import an environment 1101 CONFIG_CMD_INI * import data from an ini file into the env 1102 CONFIG_CMD_IRQ * irqinfo 1103 CONFIG_CMD_ITEST Integer/string test of 2 values 1104 CONFIG_CMD_JFFS2 * JFFS2 Support 1105 CONFIG_CMD_KGDB * kgdb 1106 CONFIG_CMD_LDRINFO * ldrinfo (display Blackfin loader) 1107 CONFIG_CMD_LINK_LOCAL * link-local IP address auto-configuration 1108 (169.254.*.*) 1109 CONFIG_CMD_LOADB loadb 1110 CONFIG_CMD_LOADS loads 1111 CONFIG_CMD_MD5SUM * print md5 message digest 1112 (requires CONFIG_CMD_MEMORY and CONFIG_MD5) 1113 CONFIG_CMD_MEMINFO * Display detailed memory information 1114 CONFIG_CMD_MEMORY md, mm, nm, mw, cp, cmp, crc, base, 1115 loop, loopw 1116 CONFIG_CMD_MEMTEST * mtest 1117 CONFIG_CMD_MISC Misc functions like sleep etc 1118 CONFIG_CMD_MMC * MMC memory mapped support 1119 CONFIG_CMD_MII * MII utility commands 1120 CONFIG_CMD_MTDPARTS * MTD partition support 1121 CONFIG_CMD_NAND * NAND support 1122 CONFIG_CMD_NET bootp, tftpboot, rarpboot 1123 CONFIG_CMD_NFS NFS support 1124 CONFIG_CMD_PCA953X * PCA953x I2C gpio commands 1125 CONFIG_CMD_PCA953X_INFO * PCA953x I2C gpio info command 1126 CONFIG_CMD_PCI * pciinfo 1127 CONFIG_CMD_PCMCIA * PCMCIA support 1128 CONFIG_CMD_PING * send ICMP ECHO_REQUEST to network 1129 host 1130 CONFIG_CMD_PORTIO * Port I/O 1131 CONFIG_CMD_READ * Read raw data from partition 1132 CONFIG_CMD_REGINFO * Register dump 1133 CONFIG_CMD_RUN run command in env variable 1134 CONFIG_CMD_SANDBOX * sb command to access sandbox features 1135 CONFIG_CMD_SAVES * save S record dump 1136 CONFIG_CMD_SCSI * SCSI Support 1137 CONFIG_CMD_SDRAM * print SDRAM configuration information 1138 (requires CONFIG_CMD_I2C) 1139 CONFIG_CMD_SETGETDCR Support for DCR Register access 1140 (4xx only) 1141 CONFIG_CMD_SF * Read/write/erase SPI NOR flash 1142 CONFIG_CMD_SHA1SUM * print sha1 memory digest 1143 (requires CONFIG_CMD_MEMORY) 1144 CONFIG_CMD_SOFTSWITCH * Soft switch setting command for BF60x 1145 CONFIG_CMD_SOURCE "source" command Support 1146 CONFIG_CMD_SPI * SPI serial bus support 1147 CONFIG_CMD_TFTPSRV * TFTP transfer in server mode 1148 CONFIG_CMD_TFTPPUT * TFTP put command (upload) 1149 CONFIG_CMD_TIME * run command and report execution time (ARM specific) 1150 CONFIG_CMD_TIMER * access to the system tick timer 1151 CONFIG_CMD_USB * USB support 1152 CONFIG_CMD_CDP * Cisco Discover Protocol support 1153 CONFIG_CMD_MFSL * Microblaze FSL support 1154 CONFIG_CMD_XIMG Load part of Multi Image 1155 CONFIG_CMD_UUID * Generate random UUID or GUID string 1156 1157 EXAMPLE: If you want all functions except of network 1158 support you can write: 1159 1160 #include "config_cmd_all.h" 1161 #undef CONFIG_CMD_NET 1162 1163 Other Commands: 1164 fdt (flattened device tree) command: CONFIG_OF_LIBFDT 1165 1166 Note: Don't enable the "icache" and "dcache" commands 1167 (configuration option CONFIG_CMD_CACHE) unless you know 1168 what you (and your U-Boot users) are doing. Data 1169 cache cannot be enabled on systems like the 8xx or 1170 8260 (where accesses to the IMMR region must be 1171 uncached), and it cannot be disabled on all other 1172 systems where we (mis-) use the data cache to hold an 1173 initial stack and some data. 1174 1175 1176 XXX - this list needs to get updated! 1177 1178- Regular expression support: 1179 CONFIG_REGEX 1180 If this variable is defined, U-Boot is linked against 1181 the SLRE (Super Light Regular Expression) library, 1182 which adds regex support to some commands, as for 1183 example "env grep" and "setexpr". 1184 1185- Device tree: 1186 CONFIG_OF_CONTROL 1187 If this variable is defined, U-Boot will use a device tree 1188 to configure its devices, instead of relying on statically 1189 compiled #defines in the board file. This option is 1190 experimental and only available on a few boards. The device 1191 tree is available in the global data as gd->fdt_blob. 1192 1193 U-Boot needs to get its device tree from somewhere. This can 1194 be done using one of the two options below: 1195 1196 CONFIG_OF_EMBED 1197 If this variable is defined, U-Boot will embed a device tree 1198 binary in its image. This device tree file should be in the 1199 board directory and called <soc>-<board>.dts. The binary file 1200 is then picked up in board_init_f() and made available through 1201 the global data structure as gd->blob. 1202 1203 CONFIG_OF_SEPARATE 1204 If this variable is defined, U-Boot will build a device tree 1205 binary. It will be called u-boot.dtb. Architecture-specific 1206 code will locate it at run-time. Generally this works by: 1207 1208 cat u-boot.bin u-boot.dtb >image.bin 1209 1210 and in fact, U-Boot does this for you, creating a file called 1211 u-boot-dtb.bin which is useful in the common case. You can 1212 still use the individual files if you need something more 1213 exotic. 1214 1215- Watchdog: 1216 CONFIG_WATCHDOG 1217 If this variable is defined, it enables watchdog 1218 support for the SoC. There must be support in the SoC 1219 specific code for a watchdog. For the 8xx and 8260 1220 CPUs, the SIU Watchdog feature is enabled in the SYPCR 1221 register. When supported for a specific SoC is 1222 available, then no further board specific code should 1223 be needed to use it. 1224 1225 CONFIG_HW_WATCHDOG 1226 When using a watchdog circuitry external to the used 1227 SoC, then define this variable and provide board 1228 specific code for the "hw_watchdog_reset" function. 1229 1230 CONFIG_AT91_HW_WDT_TIMEOUT 1231 specify the timeout in seconds. default 2 seconds. 1232 1233- U-Boot Version: 1234 CONFIG_VERSION_VARIABLE 1235 If this variable is defined, an environment variable 1236 named "ver" is created by U-Boot showing the U-Boot 1237 version as printed by the "version" command. 1238 Any change to this variable will be reverted at the 1239 next reset. 1240 1241- Real-Time Clock: 1242 1243 When CONFIG_CMD_DATE is selected, the type of the RTC 1244 has to be selected, too. Define exactly one of the 1245 following options: 1246 1247 CONFIG_RTC_MPC8xx - use internal RTC of MPC8xx 1248 CONFIG_RTC_PCF8563 - use Philips PCF8563 RTC 1249 CONFIG_RTC_MC13XXX - use MC13783 or MC13892 RTC 1250 CONFIG_RTC_MC146818 - use MC146818 RTC 1251 CONFIG_RTC_DS1307 - use Maxim, Inc. DS1307 RTC 1252 CONFIG_RTC_DS1337 - use Maxim, Inc. DS1337 RTC 1253 CONFIG_RTC_DS1338 - use Maxim, Inc. DS1338 RTC 1254 CONFIG_RTC_DS1339 - use Maxim, Inc. DS1339 RTC 1255 CONFIG_RTC_DS164x - use Dallas DS164x RTC 1256 CONFIG_RTC_ISL1208 - use Intersil ISL1208 RTC 1257 CONFIG_RTC_MAX6900 - use Maxim, Inc. MAX6900 RTC 1258 CONFIG_SYS_RTC_DS1337_NOOSC - Turn off the OSC output for DS1337 1259 CONFIG_SYS_RV3029_TCR - enable trickle charger on 1260 RV3029 RTC. 1261 1262 Note that if the RTC uses I2C, then the I2C interface 1263 must also be configured. See I2C Support, below. 1264 1265- GPIO Support: 1266 CONFIG_PCA953X - use NXP's PCA953X series I2C GPIO 1267 1268 The CONFIG_SYS_I2C_PCA953X_WIDTH option specifies a list of 1269 chip-ngpio pairs that tell the PCA953X driver the number of 1270 pins supported by a particular chip. 1271 1272 Note that if the GPIO device uses I2C, then the I2C interface 1273 must also be configured. See I2C Support, below. 1274 1275- I/O tracing: 1276 When CONFIG_IO_TRACE is selected, U-Boot intercepts all I/O 1277 accesses and can checksum them or write a list of them out 1278 to memory. See the 'iotrace' command for details. This is 1279 useful for testing device drivers since it can confirm that 1280 the driver behaves the same way before and after a code 1281 change. Currently this is supported on sandbox and arm. To 1282 add support for your architecture, add '#include <iotrace.h>' 1283 to the bottom of arch/<arch>/include/asm/io.h and test. 1284 1285 Example output from the 'iotrace stats' command is below. 1286 Note that if the trace buffer is exhausted, the checksum will 1287 still continue to operate. 1288 1289 iotrace is enabled 1290 Start: 10000000 (buffer start address) 1291 Size: 00010000 (buffer size) 1292 Offset: 00000120 (current buffer offset) 1293 Output: 10000120 (start + offset) 1294 Count: 00000018 (number of trace records) 1295 CRC32: 9526fb66 (CRC32 of all trace records) 1296 1297- Timestamp Support: 1298 1299 When CONFIG_TIMESTAMP is selected, the timestamp 1300 (date and time) of an image is printed by image 1301 commands like bootm or iminfo. This option is 1302 automatically enabled when you select CONFIG_CMD_DATE . 1303 1304- Partition Labels (disklabels) Supported: 1305 Zero or more of the following: 1306 CONFIG_MAC_PARTITION Apple's MacOS partition table. 1307 CONFIG_DOS_PARTITION MS Dos partition table, traditional on the 1308 Intel architecture, USB sticks, etc. 1309 CONFIG_ISO_PARTITION ISO partition table, used on CDROM etc. 1310 CONFIG_EFI_PARTITION GPT partition table, common when EFI is the 1311 bootloader. Note 2TB partition limit; see 1312 disk/part_efi.c 1313 CONFIG_MTD_PARTITIONS Memory Technology Device partition table. 1314 1315 If IDE or SCSI support is enabled (CONFIG_CMD_IDE or 1316 CONFIG_CMD_SCSI) you must configure support for at 1317 least one non-MTD partition type as well. 1318 1319- IDE Reset method: 1320 CONFIG_IDE_RESET_ROUTINE - this is defined in several 1321 board configurations files but used nowhere! 1322 1323 CONFIG_IDE_RESET - is this is defined, IDE Reset will 1324 be performed by calling the function 1325 ide_set_reset(int reset) 1326 which has to be defined in a board specific file 1327 1328- ATAPI Support: 1329 CONFIG_ATAPI 1330 1331 Set this to enable ATAPI support. 1332 1333- LBA48 Support 1334 CONFIG_LBA48 1335 1336 Set this to enable support for disks larger than 137GB 1337 Also look at CONFIG_SYS_64BIT_LBA. 1338 Whithout these , LBA48 support uses 32bit variables and will 'only' 1339 support disks up to 2.1TB. 1340 1341 CONFIG_SYS_64BIT_LBA: 1342 When enabled, makes the IDE subsystem use 64bit sector addresses. 1343 Default is 32bit. 1344 1345- SCSI Support: 1346 At the moment only there is only support for the 1347 SYM53C8XX SCSI controller; define 1348 CONFIG_SCSI_SYM53C8XX to enable it. 1349 1350 CONFIG_SYS_SCSI_MAX_LUN [8], CONFIG_SYS_SCSI_MAX_SCSI_ID [7] and 1351 CONFIG_SYS_SCSI_MAX_DEVICE [CONFIG_SYS_SCSI_MAX_SCSI_ID * 1352 CONFIG_SYS_SCSI_MAX_LUN] can be adjusted to define the 1353 maximum numbers of LUNs, SCSI ID's and target 1354 devices. 1355 CONFIG_SYS_SCSI_SYM53C8XX_CCF to fix clock timing (80Mhz) 1356 1357 The environment variable 'scsidevs' is set to the number of 1358 SCSI devices found during the last scan. 1359 1360- NETWORK Support (PCI): 1361 CONFIG_E1000 1362 Support for Intel 8254x/8257x gigabit chips. 1363 1364 CONFIG_E1000_SPI 1365 Utility code for direct access to the SPI bus on Intel 8257x. 1366 This does not do anything useful unless you set at least one 1367 of CONFIG_CMD_E1000 or CONFIG_E1000_SPI_GENERIC. 1368 1369 CONFIG_E1000_SPI_GENERIC 1370 Allow generic access to the SPI bus on the Intel 8257x, for 1371 example with the "sspi" command. 1372 1373 CONFIG_CMD_E1000 1374 Management command for E1000 devices. When used on devices 1375 with SPI support you can reprogram the EEPROM from U-Boot. 1376 1377 CONFIG_E1000_FALLBACK_MAC 1378 default MAC for empty EEPROM after production. 1379 1380 CONFIG_EEPRO100 1381 Support for Intel 82557/82559/82559ER chips. 1382 Optional CONFIG_EEPRO100_SROM_WRITE enables EEPROM 1383 write routine for first time initialisation. 1384 1385 CONFIG_TULIP 1386 Support for Digital 2114x chips. 1387 Optional CONFIG_TULIP_SELECT_MEDIA for board specific 1388 modem chip initialisation (KS8761/QS6611). 1389 1390 CONFIG_NATSEMI 1391 Support for National dp83815 chips. 1392 1393 CONFIG_NS8382X 1394 Support for National dp8382[01] gigabit chips. 1395 1396- NETWORK Support (other): 1397 1398 CONFIG_DRIVER_AT91EMAC 1399 Support for AT91RM9200 EMAC. 1400 1401 CONFIG_RMII 1402 Define this to use reduced MII inteface 1403 1404 CONFIG_DRIVER_AT91EMAC_QUIET 1405 If this defined, the driver is quiet. 1406 The driver doen't show link status messages. 1407 1408 CONFIG_CALXEDA_XGMAC 1409 Support for the Calxeda XGMAC device 1410 1411 CONFIG_LAN91C96 1412 Support for SMSC's LAN91C96 chips. 1413 1414 CONFIG_LAN91C96_BASE 1415 Define this to hold the physical address 1416 of the LAN91C96's I/O space 1417 1418 CONFIG_LAN91C96_USE_32_BIT 1419 Define this to enable 32 bit addressing 1420 1421 CONFIG_SMC91111 1422 Support for SMSC's LAN91C111 chip 1423 1424 CONFIG_SMC91111_BASE 1425 Define this to hold the physical address 1426 of the device (I/O space) 1427 1428 CONFIG_SMC_USE_32_BIT 1429 Define this if data bus is 32 bits 1430 1431 CONFIG_SMC_USE_IOFUNCS 1432 Define this to use i/o functions instead of macros 1433 (some hardware wont work with macros) 1434 1435 CONFIG_DRIVER_TI_EMAC 1436 Support for davinci emac 1437 1438 CONFIG_SYS_DAVINCI_EMAC_PHY_COUNT 1439 Define this if you have more then 3 PHYs. 1440 1441 CONFIG_FTGMAC100 1442 Support for Faraday's FTGMAC100 Gigabit SoC Ethernet 1443 1444 CONFIG_FTGMAC100_EGIGA 1445 Define this to use GE link update with gigabit PHY. 1446 Define this if FTGMAC100 is connected to gigabit PHY. 1447 If your system has 10/100 PHY only, it might not occur 1448 wrong behavior. Because PHY usually return timeout or 1449 useless data when polling gigabit status and gigabit 1450 control registers. This behavior won't affect the 1451 correctnessof 10/100 link speed update. 1452 1453 CONFIG_SMC911X 1454 Support for SMSC's LAN911x and LAN921x chips 1455 1456 CONFIG_SMC911X_BASE 1457 Define this to hold the physical address 1458 of the device (I/O space) 1459 1460 CONFIG_SMC911X_32_BIT 1461 Define this if data bus is 32 bits 1462 1463 CONFIG_SMC911X_16_BIT 1464 Define this if data bus is 16 bits. If your processor 1465 automatically converts one 32 bit word to two 16 bit 1466 words you may also try CONFIG_SMC911X_32_BIT. 1467 1468 CONFIG_SH_ETHER 1469 Support for Renesas on-chip Ethernet controller 1470 1471 CONFIG_SH_ETHER_USE_PORT 1472 Define the number of ports to be used 1473 1474 CONFIG_SH_ETHER_PHY_ADDR 1475 Define the ETH PHY's address 1476 1477 CONFIG_SH_ETHER_CACHE_WRITEBACK 1478 If this option is set, the driver enables cache flush. 1479 1480- PWM Support: 1481 CONFIG_PWM_IMX 1482 Support for PWM modul on the imx6. 1483 1484- TPM Support: 1485 CONFIG_TPM 1486 Support TPM devices. 1487 1488 CONFIG_TPM_TIS_I2C 1489 Support for i2c bus TPM devices. Only one device 1490 per system is supported at this time. 1491 1492 CONFIG_TPM_TIS_I2C_BUS_NUMBER 1493 Define the the i2c bus number for the TPM device 1494 1495 CONFIG_TPM_TIS_I2C_SLAVE_ADDRESS 1496 Define the TPM's address on the i2c bus 1497 1498 CONFIG_TPM_TIS_I2C_BURST_LIMITATION 1499 Define the burst count bytes upper limit 1500 1501 CONFIG_TPM_ATMEL_TWI 1502 Support for Atmel TWI TPM device. Requires I2C support. 1503 1504 CONFIG_TPM_TIS_LPC 1505 Support for generic parallel port TPM devices. Only one device 1506 per system is supported at this time. 1507 1508 CONFIG_TPM_TIS_BASE_ADDRESS 1509 Base address where the generic TPM device is mapped 1510 to. Contemporary x86 systems usually map it at 1511 0xfed40000. 1512 1513 CONFIG_CMD_TPM 1514 Add tpm monitor functions. 1515 Requires CONFIG_TPM. If CONFIG_TPM_AUTH_SESSIONS is set, also 1516 provides monitor access to authorized functions. 1517 1518 CONFIG_TPM 1519 Define this to enable the TPM support library which provides 1520 functional interfaces to some TPM commands. 1521 Requires support for a TPM device. 1522 1523 CONFIG_TPM_AUTH_SESSIONS 1524 Define this to enable authorized functions in the TPM library. 1525 Requires CONFIG_TPM and CONFIG_SHA1. 1526 1527- USB Support: 1528 At the moment only the UHCI host controller is 1529 supported (PIP405, MIP405, MPC5200); define 1530 CONFIG_USB_UHCI to enable it. 1531 define CONFIG_USB_KEYBOARD to enable the USB Keyboard 1532 and define CONFIG_USB_STORAGE to enable the USB 1533 storage devices. 1534 Note: 1535 Supported are USB Keyboards and USB Floppy drives 1536 (TEAC FD-05PUB). 1537 MPC5200 USB requires additional defines: 1538 CONFIG_USB_CLOCK 1539 for 528 MHz Clock: 0x0001bbbb 1540 CONFIG_PSC3_USB 1541 for USB on PSC3 1542 CONFIG_USB_CONFIG 1543 for differential drivers: 0x00001000 1544 for single ended drivers: 0x00005000 1545 for differential drivers on PSC3: 0x00000100 1546 for single ended drivers on PSC3: 0x00004100 1547 CONFIG_SYS_USB_EVENT_POLL 1548 May be defined to allow interrupt polling 1549 instead of using asynchronous interrupts 1550 1551 CONFIG_USB_EHCI_TXFIFO_THRESH enables setting of the 1552 txfilltuning field in the EHCI controller on reset. 1553 1554 CONFIG_USB_DWC2_REG_ADDR the physical CPU address of the DWC2 1555 HW module registers. 1556 1557- USB Device: 1558 Define the below if you wish to use the USB console. 1559 Once firmware is rebuilt from a serial console issue the 1560 command "setenv stdin usbtty; setenv stdout usbtty" and 1561 attach your USB cable. The Unix command "dmesg" should print 1562 it has found a new device. The environment variable usbtty 1563 can be set to gserial or cdc_acm to enable your device to 1564 appear to a USB host as a Linux gserial device or a 1565 Common Device Class Abstract Control Model serial device. 1566 If you select usbtty = gserial you should be able to enumerate 1567 a Linux host by 1568 # modprobe usbserial vendor=0xVendorID product=0xProductID 1569 else if using cdc_acm, simply setting the environment 1570 variable usbtty to be cdc_acm should suffice. The following 1571 might be defined in YourBoardName.h 1572 1573 CONFIG_USB_DEVICE 1574 Define this to build a UDC device 1575 1576 CONFIG_USB_TTY 1577 Define this to have a tty type of device available to 1578 talk to the UDC device 1579 1580 CONFIG_USBD_HS 1581 Define this to enable the high speed support for usb 1582 device and usbtty. If this feature is enabled, a routine 1583 int is_usbd_high_speed(void) 1584 also needs to be defined by the driver to dynamically poll 1585 whether the enumeration has succeded at high speed or full 1586 speed. 1587 1588 CONFIG_SYS_CONSOLE_IS_IN_ENV 1589 Define this if you want stdin, stdout &/or stderr to 1590 be set to usbtty. 1591 1592 mpc8xx: 1593 CONFIG_SYS_USB_EXTC_CLK 0xBLAH 1594 Derive USB clock from external clock "blah" 1595 - CONFIG_SYS_USB_EXTC_CLK 0x02 1596 1597 CONFIG_SYS_USB_BRG_CLK 0xBLAH 1598 Derive USB clock from brgclk 1599 - CONFIG_SYS_USB_BRG_CLK 0x04 1600 1601 If you have a USB-IF assigned VendorID then you may wish to 1602 define your own vendor specific values either in BoardName.h 1603 or directly in usbd_vendor_info.h. If you don't define 1604 CONFIG_USBD_MANUFACTURER, CONFIG_USBD_PRODUCT_NAME, 1605 CONFIG_USBD_VENDORID and CONFIG_USBD_PRODUCTID, then U-Boot 1606 should pretend to be a Linux device to it's target host. 1607 1608 CONFIG_USBD_MANUFACTURER 1609 Define this string as the name of your company for 1610 - CONFIG_USBD_MANUFACTURER "my company" 1611 1612 CONFIG_USBD_PRODUCT_NAME 1613 Define this string as the name of your product 1614 - CONFIG_USBD_PRODUCT_NAME "acme usb device" 1615 1616 CONFIG_USBD_VENDORID 1617 Define this as your assigned Vendor ID from the USB 1618 Implementors Forum. This *must* be a genuine Vendor ID 1619 to avoid polluting the USB namespace. 1620 - CONFIG_USBD_VENDORID 0xFFFF 1621 1622 CONFIG_USBD_PRODUCTID 1623 Define this as the unique Product ID 1624 for your device 1625 - CONFIG_USBD_PRODUCTID 0xFFFF 1626 1627- ULPI Layer Support: 1628 The ULPI (UTMI Low Pin (count) Interface) PHYs are supported via 1629 the generic ULPI layer. The generic layer accesses the ULPI PHY 1630 via the platform viewport, so you need both the genric layer and 1631 the viewport enabled. Currently only Chipidea/ARC based 1632 viewport is supported. 1633 To enable the ULPI layer support, define CONFIG_USB_ULPI and 1634 CONFIG_USB_ULPI_VIEWPORT in your board configuration file. 1635 If your ULPI phy needs a different reference clock than the 1636 standard 24 MHz then you have to define CONFIG_ULPI_REF_CLK to 1637 the appropriate value in Hz. 1638 1639- MMC Support: 1640 The MMC controller on the Intel PXA is supported. To 1641 enable this define CONFIG_MMC. The MMC can be 1642 accessed from the boot prompt by mapping the device 1643 to physical memory similar to flash. Command line is 1644 enabled with CONFIG_CMD_MMC. The MMC driver also works with 1645 the FAT fs. This is enabled with CONFIG_CMD_FAT. 1646 1647 CONFIG_SH_MMCIF 1648 Support for Renesas on-chip MMCIF controller 1649 1650 CONFIG_SH_MMCIF_ADDR 1651 Define the base address of MMCIF registers 1652 1653 CONFIG_SH_MMCIF_CLK 1654 Define the clock frequency for MMCIF 1655 1656 CONFIG_GENERIC_MMC 1657 Enable the generic MMC driver 1658 1659 CONFIG_SUPPORT_EMMC_BOOT 1660 Enable some additional features of the eMMC boot partitions. 1661 1662 CONFIG_SUPPORT_EMMC_RPMB 1663 Enable the commands for reading, writing and programming the 1664 key for the Replay Protection Memory Block partition in eMMC. 1665 1666- USB Device Firmware Update (DFU) class support: 1667 CONFIG_DFU_FUNCTION 1668 This enables the USB portion of the DFU USB class 1669 1670 CONFIG_CMD_DFU 1671 This enables the command "dfu" which is used to have 1672 U-Boot create a DFU class device via USB. This command 1673 requires that the "dfu_alt_info" environment variable be 1674 set and define the alt settings to expose to the host. 1675 1676 CONFIG_DFU_MMC 1677 This enables support for exposing (e)MMC devices via DFU. 1678 1679 CONFIG_DFU_NAND 1680 This enables support for exposing NAND devices via DFU. 1681 1682 CONFIG_DFU_RAM 1683 This enables support for exposing RAM via DFU. 1684 Note: DFU spec refer to non-volatile memory usage, but 1685 allow usages beyond the scope of spec - here RAM usage, 1686 one that would help mostly the developer. 1687 1688 CONFIG_SYS_DFU_DATA_BUF_SIZE 1689 Dfu transfer uses a buffer before writing data to the 1690 raw storage device. Make the size (in bytes) of this buffer 1691 configurable. The size of this buffer is also configurable 1692 through the "dfu_bufsiz" environment variable. 1693 1694 CONFIG_SYS_DFU_MAX_FILE_SIZE 1695 When updating files rather than the raw storage device, 1696 we use a static buffer to copy the file into and then write 1697 the buffer once we've been given the whole file. Define 1698 this to the maximum filesize (in bytes) for the buffer. 1699 Default is 4 MiB if undefined. 1700 1701 DFU_DEFAULT_POLL_TIMEOUT 1702 Poll timeout [ms], is the timeout a device can send to the 1703 host. The host must wait for this timeout before sending 1704 a subsequent DFU_GET_STATUS request to the device. 1705 1706 DFU_MANIFEST_POLL_TIMEOUT 1707 Poll timeout [ms], which the device sends to the host when 1708 entering dfuMANIFEST state. Host waits this timeout, before 1709 sending again an USB request to the device. 1710 1711- USB Device Android Fastboot support: 1712 CONFIG_CMD_FASTBOOT 1713 This enables the command "fastboot" which enables the Android 1714 fastboot mode for the platform's USB device. Fastboot is a USB 1715 protocol for downloading images, flashing and device control 1716 used on Android devices. 1717 See doc/README.android-fastboot for more information. 1718 1719 CONFIG_ANDROID_BOOT_IMAGE 1720 This enables support for booting images which use the Android 1721 image format header. 1722 1723 CONFIG_USB_FASTBOOT_BUF_ADDR 1724 The fastboot protocol requires a large memory buffer for 1725 downloads. Define this to the starting RAM address to use for 1726 downloaded images. 1727 1728 CONFIG_USB_FASTBOOT_BUF_SIZE 1729 The fastboot protocol requires a large memory buffer for 1730 downloads. This buffer should be as large as possible for a 1731 platform. Define this to the size available RAM for fastboot. 1732 1733 CONFIG_FASTBOOT_FLASH 1734 The fastboot protocol includes a "flash" command for writing 1735 the downloaded image to a non-volatile storage device. Define 1736 this to enable the "fastboot flash" command. 1737 1738 CONFIG_FASTBOOT_FLASH_MMC_DEV 1739 The fastboot "flash" command requires additional information 1740 regarding the non-volatile storage device. Define this to 1741 the eMMC device that fastboot should use to store the image. 1742 1743 CONFIG_FASTBOOT_GPT_NAME 1744 The fastboot "flash" command supports writing the downloaded 1745 image to the Protective MBR and the Primary GUID Partition 1746 Table. (Additionally, this downloaded image is post-processed 1747 to generate and write the Backup GUID Partition Table.) 1748 This occurs when the specified "partition name" on the 1749 "fastboot flash" command line matches this value. 1750 Default is GPT_ENTRY_NAME (currently "gpt") if undefined. 1751 1752- Journaling Flash filesystem support: 1753 CONFIG_JFFS2_NAND, CONFIG_JFFS2_NAND_OFF, CONFIG_JFFS2_NAND_SIZE, 1754 CONFIG_JFFS2_NAND_DEV 1755 Define these for a default partition on a NAND device 1756 1757 CONFIG_SYS_JFFS2_FIRST_SECTOR, 1758 CONFIG_SYS_JFFS2_FIRST_BANK, CONFIG_SYS_JFFS2_NUM_BANKS 1759 Define these for a default partition on a NOR device 1760 1761 CONFIG_SYS_JFFS_CUSTOM_PART 1762 Define this to create an own partition. You have to provide a 1763 function struct part_info* jffs2_part_info(int part_num) 1764 1765 If you define only one JFFS2 partition you may also want to 1766 #define CONFIG_SYS_JFFS_SINGLE_PART 1 1767 to disable the command chpart. This is the default when you 1768 have not defined a custom partition 1769 1770- FAT(File Allocation Table) filesystem write function support: 1771 CONFIG_FAT_WRITE 1772 1773 Define this to enable support for saving memory data as a 1774 file in FAT formatted partition. 1775 1776 This will also enable the command "fatwrite" enabling the 1777 user to write files to FAT. 1778 1779CBFS (Coreboot Filesystem) support 1780 CONFIG_CMD_CBFS 1781 1782 Define this to enable support for reading from a Coreboot 1783 filesystem. Available commands are cbfsinit, cbfsinfo, cbfsls 1784 and cbfsload. 1785 1786- FAT(File Allocation Table) filesystem cluster size: 1787 CONFIG_FS_FAT_MAX_CLUSTSIZE 1788 1789 Define the max cluster size for fat operations else 1790 a default value of 65536 will be defined. 1791 1792- Keyboard Support: 1793 CONFIG_ISA_KEYBOARD 1794 1795 Define this to enable standard (PC-Style) keyboard 1796 support 1797 1798 CONFIG_I8042_KBD 1799 Standard PC keyboard driver with US (is default) and 1800 GERMAN key layout (switch via environment 'keymap=de') support. 1801 Export function i8042_kbd_init, i8042_tstc and i8042_getc 1802 for cfb_console. Supports cursor blinking. 1803 1804 CONFIG_CROS_EC_KEYB 1805 Enables a Chrome OS keyboard using the CROS_EC interface. 1806 This uses CROS_EC to communicate with a second microcontroller 1807 which provides key scans on request. 1808 1809- Video support: 1810 CONFIG_VIDEO 1811 1812 Define this to enable video support (for output to 1813 video). 1814 1815 CONFIG_VIDEO_CT69000 1816 1817 Enable Chips & Technologies 69000 Video chip 1818 1819 CONFIG_VIDEO_SMI_LYNXEM 1820 Enable Silicon Motion SMI 712/710/810 Video chip. The 1821 video output is selected via environment 'videoout' 1822 (1 = LCD and 2 = CRT). If videoout is undefined, CRT is 1823 assumed. 1824 1825 For the CT69000 and SMI_LYNXEM drivers, videomode is 1826 selected via environment 'videomode'. Two different ways 1827 are possible: 1828 - "videomode=num" 'num' is a standard LiLo mode numbers. 1829 Following standard modes are supported (* is default): 1830 1831 Colors 640x480 800x600 1024x768 1152x864 1280x1024 1832 -------------+--------------------------------------------- 1833 8 bits | 0x301* 0x303 0x305 0x161 0x307 1834 15 bits | 0x310 0x313 0x316 0x162 0x319 1835 16 bits | 0x311 0x314 0x317 0x163 0x31A 1836 24 bits | 0x312 0x315 0x318 ? 0x31B 1837 -------------+--------------------------------------------- 1838 (i.e. setenv videomode 317; saveenv; reset;) 1839 1840 - "videomode=bootargs" all the video parameters are parsed 1841 from the bootargs. (See drivers/video/videomodes.c) 1842 1843 1844 CONFIG_VIDEO_SED13806 1845 Enable Epson SED13806 driver. This driver supports 8bpp 1846 and 16bpp modes defined by CONFIG_VIDEO_SED13806_8BPP 1847 or CONFIG_VIDEO_SED13806_16BPP 1848 1849 CONFIG_FSL_DIU_FB 1850 Enable the Freescale DIU video driver. Reference boards for 1851 SOCs that have a DIU should define this macro to enable DIU 1852 support, and should also define these other macros: 1853 1854 CONFIG_SYS_DIU_ADDR 1855 CONFIG_VIDEO 1856 CONFIG_CMD_BMP 1857 CONFIG_CFB_CONSOLE 1858 CONFIG_VIDEO_SW_CURSOR 1859 CONFIG_VGA_AS_SINGLE_DEVICE 1860 CONFIG_VIDEO_LOGO 1861 CONFIG_VIDEO_BMP_LOGO 1862 1863 The DIU driver will look for the 'video-mode' environment 1864 variable, and if defined, enable the DIU as a console during 1865 boot. See the documentation file README.video for a 1866 description of this variable. 1867 1868 CONFIG_VIDEO_VGA 1869 1870 Enable the VGA video / BIOS for x86. The alternative if you 1871 are using coreboot is to use the coreboot frame buffer 1872 driver. 1873 1874 1875- Keyboard Support: 1876 CONFIG_KEYBOARD 1877 1878 Define this to enable a custom keyboard support. 1879 This simply calls drv_keyboard_init() which must be 1880 defined in your board-specific files. 1881 The only board using this so far is RBC823. 1882 1883- LCD Support: CONFIG_LCD 1884 1885 Define this to enable LCD support (for output to LCD 1886 display); also select one of the supported displays 1887 by defining one of these: 1888 1889 CONFIG_ATMEL_LCD: 1890 1891 HITACHI TX09D70VM1CCA, 3.5", 240x320. 1892 1893 CONFIG_NEC_NL6448AC33: 1894 1895 NEC NL6448AC33-18. Active, color, single scan. 1896 1897 CONFIG_NEC_NL6448BC20 1898 1899 NEC NL6448BC20-08. 6.5", 640x480. 1900 Active, color, single scan. 1901 1902 CONFIG_NEC_NL6448BC33_54 1903 1904 NEC NL6448BC33-54. 10.4", 640x480. 1905 Active, color, single scan. 1906 1907 CONFIG_SHARP_16x9 1908 1909 Sharp 320x240. Active, color, single scan. 1910 It isn't 16x9, and I am not sure what it is. 1911 1912 CONFIG_SHARP_LQ64D341 1913 1914 Sharp LQ64D341 display, 640x480. 1915 Active, color, single scan. 1916 1917 CONFIG_HLD1045 1918 1919 HLD1045 display, 640x480. 1920 Active, color, single scan. 1921 1922 CONFIG_OPTREX_BW 1923 1924 Optrex CBL50840-2 NF-FW 99 22 M5 1925 or 1926 Hitachi LMG6912RPFC-00T 1927 or 1928 Hitachi SP14Q002 1929 1930 320x240. Black & white. 1931 1932 Normally display is black on white background; define 1933 CONFIG_SYS_WHITE_ON_BLACK to get it inverted. 1934 1935 CONFIG_LCD_ALIGNMENT 1936 1937 Normally the LCD is page-aligned (typically 4KB). If this is 1938 defined then the LCD will be aligned to this value instead. 1939 For ARM it is sometimes useful to use MMU_SECTION_SIZE 1940 here, since it is cheaper to change data cache settings on 1941 a per-section basis. 1942 1943 CONFIG_CONSOLE_SCROLL_LINES 1944 1945 When the console need to be scrolled, this is the number of 1946 lines to scroll by. It defaults to 1. Increasing this makes 1947 the console jump but can help speed up operation when scrolling 1948 is slow. 1949 1950 CONFIG_LCD_BMP_RLE8 1951 1952 Support drawing of RLE8-compressed bitmaps on the LCD. 1953 1954 CONFIG_I2C_EDID 1955 1956 Enables an 'i2c edid' command which can read EDID 1957 information over I2C from an attached LCD display. 1958 1959- Splash Screen Support: CONFIG_SPLASH_SCREEN 1960 1961 If this option is set, the environment is checked for 1962 a variable "splashimage". If found, the usual display 1963 of logo, copyright and system information on the LCD 1964 is suppressed and the BMP image at the address 1965 specified in "splashimage" is loaded instead. The 1966 console is redirected to the "nulldev", too. This 1967 allows for a "silent" boot where a splash screen is 1968 loaded very quickly after power-on. 1969 1970 CONFIG_SPLASHIMAGE_GUARD 1971 1972 If this option is set, then U-Boot will prevent the environment 1973 variable "splashimage" from being set to a problematic address 1974 (see README.displaying-bmps). 1975 This option is useful for targets where, due to alignment 1976 restrictions, an improperly aligned BMP image will cause a data 1977 abort. If you think you will not have problems with unaligned 1978 accesses (for example because your toolchain prevents them) 1979 there is no need to set this option. 1980 1981 CONFIG_SPLASH_SCREEN_ALIGN 1982 1983 If this option is set the splash image can be freely positioned 1984 on the screen. Environment variable "splashpos" specifies the 1985 position as "x,y". If a positive number is given it is used as 1986 number of pixel from left/top. If a negative number is given it 1987 is used as number of pixel from right/bottom. You can also 1988 specify 'm' for centering the image. 1989 1990 Example: 1991 setenv splashpos m,m 1992 => image at center of screen 1993 1994 setenv splashpos 30,20 1995 => image at x = 30 and y = 20 1996 1997 setenv splashpos -10,m 1998 => vertically centered image 1999 at x = dspWidth - bmpWidth - 9 2000 2001- Gzip compressed BMP image support: CONFIG_VIDEO_BMP_GZIP 2002 2003 If this option is set, additionally to standard BMP 2004 images, gzipped BMP images can be displayed via the 2005 splashscreen support or the bmp command. 2006 2007- Run length encoded BMP image (RLE8) support: CONFIG_VIDEO_BMP_RLE8 2008 2009 If this option is set, 8-bit RLE compressed BMP images 2010 can be displayed via the splashscreen support or the 2011 bmp command. 2012 2013- Do compressing for memory range: 2014 CONFIG_CMD_ZIP 2015 2016 If this option is set, it would use zlib deflate method 2017 to compress the specified memory at its best effort. 2018 2019- Compression support: 2020 CONFIG_GZIP 2021 2022 Enabled by default to support gzip compressed images. 2023 2024 CONFIG_BZIP2 2025 2026 If this option is set, support for bzip2 compressed 2027 images is included. If not, only uncompressed and gzip 2028 compressed images are supported. 2029 2030 NOTE: the bzip2 algorithm requires a lot of RAM, so 2031 the malloc area (as defined by CONFIG_SYS_MALLOC_LEN) should 2032 be at least 4MB. 2033 2034 CONFIG_LZMA 2035 2036 If this option is set, support for lzma compressed 2037 images is included. 2038 2039 Note: The LZMA algorithm adds between 2 and 4KB of code and it 2040 requires an amount of dynamic memory that is given by the 2041 formula: 2042 2043 (1846 + 768 << (lc + lp)) * sizeof(uint16) 2044 2045 Where lc and lp stand for, respectively, Literal context bits 2046 and Literal pos bits. 2047 2048 This value is upper-bounded by 14MB in the worst case. Anyway, 2049 for a ~4MB large kernel image, we have lc=3 and lp=0 for a 2050 total amount of (1846 + 768 << (3 + 0)) * 2 = ~41KB... that is 2051 a very small buffer. 2052 2053 Use the lzmainfo tool to determinate the lc and lp values and 2054 then calculate the amount of needed dynamic memory (ensuring 2055 the appropriate CONFIG_SYS_MALLOC_LEN value). 2056 2057 CONFIG_LZO 2058 2059 If this option is set, support for LZO compressed images 2060 is included. 2061 2062- MII/PHY support: 2063 CONFIG_PHY_ADDR 2064 2065 The address of PHY on MII bus. 2066 2067 CONFIG_PHY_CLOCK_FREQ (ppc4xx) 2068 2069 The clock frequency of the MII bus 2070 2071 CONFIG_PHY_GIGE 2072 2073 If this option is set, support for speed/duplex 2074 detection of gigabit PHY is included. 2075 2076 CONFIG_PHY_RESET_DELAY 2077 2078 Some PHY like Intel LXT971A need extra delay after 2079 reset before any MII register access is possible. 2080 For such PHY, set this option to the usec delay 2081 required. (minimum 300usec for LXT971A) 2082 2083 CONFIG_PHY_CMD_DELAY (ppc4xx) 2084 2085 Some PHY like Intel LXT971A need extra delay after 2086 command issued before MII status register can be read 2087 2088- Ethernet address: 2089 CONFIG_ETHADDR 2090 CONFIG_ETH1ADDR 2091 CONFIG_ETH2ADDR 2092 CONFIG_ETH3ADDR 2093 CONFIG_ETH4ADDR 2094 CONFIG_ETH5ADDR 2095 2096 Define a default value for Ethernet address to use 2097 for the respective Ethernet interface, in case this 2098 is not determined automatically. 2099 2100- IP address: 2101 CONFIG_IPADDR 2102 2103 Define a default value for the IP address to use for 2104 the default Ethernet interface, in case this is not 2105 determined through e.g. bootp. 2106 (Environment variable "ipaddr") 2107 2108- Server IP address: 2109 CONFIG_SERVERIP 2110 2111 Defines a default value for the IP address of a TFTP 2112 server to contact when using the "tftboot" command. 2113 (Environment variable "serverip") 2114 2115 CONFIG_KEEP_SERVERADDR 2116 2117 Keeps the server's MAC address, in the env 'serveraddr' 2118 for passing to bootargs (like Linux's netconsole option) 2119 2120- Gateway IP address: 2121 CONFIG_GATEWAYIP 2122 2123 Defines a default value for the IP address of the 2124 default router where packets to other networks are 2125 sent to. 2126 (Environment variable "gatewayip") 2127 2128- Subnet mask: 2129 CONFIG_NETMASK 2130 2131 Defines a default value for the subnet mask (or 2132 routing prefix) which is used to determine if an IP 2133 address belongs to the local subnet or needs to be 2134 forwarded through a router. 2135 (Environment variable "netmask") 2136 2137- Multicast TFTP Mode: 2138 CONFIG_MCAST_TFTP 2139 2140 Defines whether you want to support multicast TFTP as per 2141 rfc-2090; for example to work with atftp. Lets lots of targets 2142 tftp down the same boot image concurrently. Note: the Ethernet 2143 driver in use must provide a function: mcast() to join/leave a 2144 multicast group. 2145 2146- BOOTP Recovery Mode: 2147 CONFIG_BOOTP_RANDOM_DELAY 2148 2149 If you have many targets in a network that try to 2150 boot using BOOTP, you may want to avoid that all 2151 systems send out BOOTP requests at precisely the same 2152 moment (which would happen for instance at recovery 2153 from a power failure, when all systems will try to 2154 boot, thus flooding the BOOTP server. Defining 2155 CONFIG_BOOTP_RANDOM_DELAY causes a random delay to be 2156 inserted before sending out BOOTP requests. The 2157 following delays are inserted then: 2158 2159 1st BOOTP request: delay 0 ... 1 sec 2160 2nd BOOTP request: delay 0 ... 2 sec 2161 3rd BOOTP request: delay 0 ... 4 sec 2162 4th and following 2163 BOOTP requests: delay 0 ... 8 sec 2164 2165 CONFIG_BOOTP_ID_CACHE_SIZE 2166 2167 BOOTP packets are uniquely identified using a 32-bit ID. The 2168 server will copy the ID from client requests to responses and 2169 U-Boot will use this to determine if it is the destination of 2170 an incoming response. Some servers will check that addresses 2171 aren't in use before handing them out (usually using an ARP 2172 ping) and therefore take up to a few hundred milliseconds to 2173 respond. Network congestion may also influence the time it 2174 takes for a response to make it back to the client. If that 2175 time is too long, U-Boot will retransmit requests. In order 2176 to allow earlier responses to still be accepted after these 2177 retransmissions, U-Boot's BOOTP client keeps a small cache of 2178 IDs. The CONFIG_BOOTP_ID_CACHE_SIZE controls the size of this 2179 cache. The default is to keep IDs for up to four outstanding 2180 requests. Increasing this will allow U-Boot to accept offers 2181 from a BOOTP client in networks with unusually high latency. 2182 2183- DHCP Advanced Options: 2184 You can fine tune the DHCP functionality by defining 2185 CONFIG_BOOTP_* symbols: 2186 2187 CONFIG_BOOTP_SUBNETMASK 2188 CONFIG_BOOTP_GATEWAY 2189 CONFIG_BOOTP_HOSTNAME 2190 CONFIG_BOOTP_NISDOMAIN 2191 CONFIG_BOOTP_BOOTPATH 2192 CONFIG_BOOTP_BOOTFILESIZE 2193 CONFIG_BOOTP_DNS 2194 CONFIG_BOOTP_DNS2 2195 CONFIG_BOOTP_SEND_HOSTNAME 2196 CONFIG_BOOTP_NTPSERVER 2197 CONFIG_BOOTP_TIMEOFFSET 2198 CONFIG_BOOTP_VENDOREX 2199 CONFIG_BOOTP_MAY_FAIL 2200 2201 CONFIG_BOOTP_SERVERIP - TFTP server will be the serverip 2202 environment variable, not the BOOTP server. 2203 2204 CONFIG_BOOTP_MAY_FAIL - If the DHCP server is not found 2205 after the configured retry count, the call will fail 2206 instead of starting over. This can be used to fail over 2207 to Link-local IP address configuration if the DHCP server 2208 is not available. 2209 2210 CONFIG_BOOTP_DNS2 - If a DHCP client requests the DNS 2211 serverip from a DHCP server, it is possible that more 2212 than one DNS serverip is offered to the client. 2213 If CONFIG_BOOTP_DNS2 is enabled, the secondary DNS 2214 serverip will be stored in the additional environment 2215 variable "dnsip2". The first DNS serverip is always 2216 stored in the variable "dnsip", when CONFIG_BOOTP_DNS 2217 is defined. 2218 2219 CONFIG_BOOTP_SEND_HOSTNAME - Some DHCP servers are capable 2220 to do a dynamic update of a DNS server. To do this, they 2221 need the hostname of the DHCP requester. 2222 If CONFIG_BOOTP_SEND_HOSTNAME is defined, the content 2223 of the "hostname" environment variable is passed as 2224 option 12 to the DHCP server. 2225 2226 CONFIG_BOOTP_DHCP_REQUEST_DELAY 2227 2228 A 32bit value in microseconds for a delay between 2229 receiving a "DHCP Offer" and sending the "DHCP Request". 2230 This fixes a problem with certain DHCP servers that don't 2231 respond 100% of the time to a "DHCP request". E.g. On an 2232 AT91RM9200 processor running at 180MHz, this delay needed 2233 to be *at least* 15,000 usec before a Windows Server 2003 2234 DHCP server would reply 100% of the time. I recommend at 2235 least 50,000 usec to be safe. The alternative is to hope 2236 that one of the retries will be successful but note that 2237 the DHCP timeout and retry process takes a longer than 2238 this delay. 2239 2240 - Link-local IP address negotiation: 2241 Negotiate with other link-local clients on the local network 2242 for an address that doesn't require explicit configuration. 2243 This is especially useful if a DHCP server cannot be guaranteed 2244 to exist in all environments that the device must operate. 2245 2246 See doc/README.link-local for more information. 2247 2248 - CDP Options: 2249 CONFIG_CDP_DEVICE_ID 2250 2251 The device id used in CDP trigger frames. 2252 2253 CONFIG_CDP_DEVICE_ID_PREFIX 2254 2255 A two character string which is prefixed to the MAC address 2256 of the device. 2257 2258 CONFIG_CDP_PORT_ID 2259 2260 A printf format string which contains the ascii name of 2261 the port. Normally is set to "eth%d" which sets 2262 eth0 for the first Ethernet, eth1 for the second etc. 2263 2264 CONFIG_CDP_CAPABILITIES 2265 2266 A 32bit integer which indicates the device capabilities; 2267 0x00000010 for a normal host which does not forwards. 2268 2269 CONFIG_CDP_VERSION 2270 2271 An ascii string containing the version of the software. 2272 2273 CONFIG_CDP_PLATFORM 2274 2275 An ascii string containing the name of the platform. 2276 2277 CONFIG_CDP_TRIGGER 2278 2279 A 32bit integer sent on the trigger. 2280 2281 CONFIG_CDP_POWER_CONSUMPTION 2282 2283 A 16bit integer containing the power consumption of the 2284 device in .1 of milliwatts. 2285 2286 CONFIG_CDP_APPLIANCE_VLAN_TYPE 2287 2288 A byte containing the id of the VLAN. 2289 2290- Status LED: CONFIG_STATUS_LED 2291 2292 Several configurations allow to display the current 2293 status using a LED. For instance, the LED will blink 2294 fast while running U-Boot code, stop blinking as 2295 soon as a reply to a BOOTP request was received, and 2296 start blinking slow once the Linux kernel is running 2297 (supported by a status LED driver in the Linux 2298 kernel). Defining CONFIG_STATUS_LED enables this 2299 feature in U-Boot. 2300 2301 Additional options: 2302 2303 CONFIG_GPIO_LED 2304 The status LED can be connected to a GPIO pin. 2305 In such cases, the gpio_led driver can be used as a 2306 status LED backend implementation. Define CONFIG_GPIO_LED 2307 to include the gpio_led driver in the U-Boot binary. 2308 2309 CONFIG_GPIO_LED_INVERTED_TABLE 2310 Some GPIO connected LEDs may have inverted polarity in which 2311 case the GPIO high value corresponds to LED off state and 2312 GPIO low value corresponds to LED on state. 2313 In such cases CONFIG_GPIO_LED_INVERTED_TABLE may be defined 2314 with a list of GPIO LEDs that have inverted polarity. 2315 2316- CAN Support: CONFIG_CAN_DRIVER 2317 2318 Defining CONFIG_CAN_DRIVER enables CAN driver support 2319 on those systems that support this (optional) 2320 feature, like the TQM8xxL modules. 2321 2322- I2C Support: CONFIG_SYS_I2C 2323 2324 This enable the NEW i2c subsystem, and will allow you to use 2325 i2c commands at the u-boot command line (as long as you set 2326 CONFIG_CMD_I2C in CONFIG_COMMANDS) and communicate with i2c 2327 based realtime clock chips or other i2c devices. See 2328 common/cmd_i2c.c for a description of the command line 2329 interface. 2330 2331 ported i2c driver to the new framework: 2332 - drivers/i2c/soft_i2c.c: 2333 - activate first bus with CONFIG_SYS_I2C_SOFT define 2334 CONFIG_SYS_I2C_SOFT_SPEED and CONFIG_SYS_I2C_SOFT_SLAVE 2335 for defining speed and slave address 2336 - activate second bus with I2C_SOFT_DECLARATIONS2 define 2337 CONFIG_SYS_I2C_SOFT_SPEED_2 and CONFIG_SYS_I2C_SOFT_SLAVE_2 2338 for defining speed and slave address 2339 - activate third bus with I2C_SOFT_DECLARATIONS3 define 2340 CONFIG_SYS_I2C_SOFT_SPEED_3 and CONFIG_SYS_I2C_SOFT_SLAVE_3 2341 for defining speed and slave address 2342 - activate fourth bus with I2C_SOFT_DECLARATIONS4 define 2343 CONFIG_SYS_I2C_SOFT_SPEED_4 and CONFIG_SYS_I2C_SOFT_SLAVE_4 2344 for defining speed and slave address 2345 2346 - drivers/i2c/fsl_i2c.c: 2347 - activate i2c driver with CONFIG_SYS_I2C_FSL 2348 define CONFIG_SYS_FSL_I2C_OFFSET for setting the register 2349 offset CONFIG_SYS_FSL_I2C_SPEED for the i2c speed and 2350 CONFIG_SYS_FSL_I2C_SLAVE for the slave addr of the first 2351 bus. 2352 - If your board supports a second fsl i2c bus, define 2353 CONFIG_SYS_FSL_I2C2_OFFSET for the register offset 2354 CONFIG_SYS_FSL_I2C2_SPEED for the speed and 2355 CONFIG_SYS_FSL_I2C2_SLAVE for the slave address of the 2356 second bus. 2357 2358 - drivers/i2c/tegra_i2c.c: 2359 - activate this driver with CONFIG_SYS_I2C_TEGRA 2360 - This driver adds 4 i2c buses with a fix speed from 2361 100000 and the slave addr 0! 2362 2363 - drivers/i2c/ppc4xx_i2c.c 2364 - activate this driver with CONFIG_SYS_I2C_PPC4XX 2365 - CONFIG_SYS_I2C_PPC4XX_CH0 activate hardware channel 0 2366 - CONFIG_SYS_I2C_PPC4XX_CH1 activate hardware channel 1 2367 2368 - drivers/i2c/i2c_mxc.c 2369 - activate this driver with CONFIG_SYS_I2C_MXC 2370 - define speed for bus 1 with CONFIG_SYS_MXC_I2C1_SPEED 2371 - define slave for bus 1 with CONFIG_SYS_MXC_I2C1_SLAVE 2372 - define speed for bus 2 with CONFIG_SYS_MXC_I2C2_SPEED 2373 - define slave for bus 2 with CONFIG_SYS_MXC_I2C2_SLAVE 2374 - define speed for bus 3 with CONFIG_SYS_MXC_I2C3_SPEED 2375 - define slave for bus 3 with CONFIG_SYS_MXC_I2C3_SLAVE 2376 If those defines are not set, default value is 100000 2377 for speed, and 0 for slave. 2378 2379 - drivers/i2c/rcar_i2c.c: 2380 - activate this driver with CONFIG_SYS_I2C_RCAR 2381 - This driver adds 4 i2c buses 2382 2383 - CONFIG_SYS_RCAR_I2C0_BASE for setting the register channel 0 2384 - CONFIG_SYS_RCAR_I2C0_SPEED for for the speed channel 0 2385 - CONFIG_SYS_RCAR_I2C1_BASE for setting the register channel 1 2386 - CONFIG_SYS_RCAR_I2C1_SPEED for for the speed channel 1 2387 - CONFIG_SYS_RCAR_I2C2_BASE for setting the register channel 2 2388 - CONFIG_SYS_RCAR_I2C2_SPEED for for the speed channel 2 2389 - CONFIG_SYS_RCAR_I2C3_BASE for setting the register channel 3 2390 - CONFIG_SYS_RCAR_I2C3_SPEED for for the speed channel 3 2391 - CONFIF_SYS_RCAR_I2C_NUM_CONTROLLERS for number of i2c buses 2392 2393 - drivers/i2c/sh_i2c.c: 2394 - activate this driver with CONFIG_SYS_I2C_SH 2395 - This driver adds from 2 to 5 i2c buses 2396 2397 - CONFIG_SYS_I2C_SH_BASE0 for setting the register channel 0 2398 - CONFIG_SYS_I2C_SH_SPEED0 for for the speed channel 0 2399 - CONFIG_SYS_I2C_SH_BASE1 for setting the register channel 1 2400 - CONFIG_SYS_I2C_SH_SPEED1 for for the speed channel 1 2401 - CONFIG_SYS_I2C_SH_BASE2 for setting the register channel 2 2402 - CONFIG_SYS_I2C_SH_SPEED2 for for the speed channel 2 2403 - CONFIG_SYS_I2C_SH_BASE3 for setting the register channel 3 2404 - CONFIG_SYS_I2C_SH_SPEED3 for for the speed channel 3 2405 - CONFIG_SYS_I2C_SH_BASE4 for setting the register channel 4 2406 - CONFIG_SYS_I2C_SH_SPEED4 for for the speed channel 4 2407 - CONFIG_SYS_I2C_SH_BASE5 for setting the register channel 5 2408 - CONFIG_SYS_I2C_SH_SPEED5 for for the speed channel 5 2409 - CONFIG_SYS_I2C_SH_NUM_CONTROLLERS for number of i2c buses 2410 2411 - drivers/i2c/omap24xx_i2c.c 2412 - activate this driver with CONFIG_SYS_I2C_OMAP24XX 2413 - CONFIG_SYS_OMAP24_I2C_SPEED speed channel 0 2414 - CONFIG_SYS_OMAP24_I2C_SLAVE slave addr channel 0 2415 - CONFIG_SYS_OMAP24_I2C_SPEED1 speed channel 1 2416 - CONFIG_SYS_OMAP24_I2C_SLAVE1 slave addr channel 1 2417 - CONFIG_SYS_OMAP24_I2C_SPEED2 speed channel 2 2418 - CONFIG_SYS_OMAP24_I2C_SLAVE2 slave addr channel 2 2419 - CONFIG_SYS_OMAP24_I2C_SPEED3 speed channel 3 2420 - CONFIG_SYS_OMAP24_I2C_SLAVE3 slave addr channel 3 2421 - CONFIG_SYS_OMAP24_I2C_SPEED4 speed channel 4 2422 - CONFIG_SYS_OMAP24_I2C_SLAVE4 slave addr channel 4 2423 2424 - drivers/i2c/zynq_i2c.c 2425 - activate this driver with CONFIG_SYS_I2C_ZYNQ 2426 - set CONFIG_SYS_I2C_ZYNQ_SPEED for speed setting 2427 - set CONFIG_SYS_I2C_ZYNQ_SLAVE for slave addr 2428 2429 - drivers/i2c/s3c24x0_i2c.c: 2430 - activate this driver with CONFIG_SYS_I2C_S3C24X0 2431 - This driver adds i2c buses (11 for Exynos5250, Exynos5420 2432 9 i2c buses for Exynos4 and 1 for S3C24X0 SoCs from Samsung) 2433 with a fix speed from 100000 and the slave addr 0! 2434 2435 - drivers/i2c/ihs_i2c.c 2436 - activate this driver with CONFIG_SYS_I2C_IHS 2437 - CONFIG_SYS_I2C_IHS_CH0 activate hardware channel 0 2438 - CONFIG_SYS_I2C_IHS_SPEED_0 speed channel 0 2439 - CONFIG_SYS_I2C_IHS_SLAVE_0 slave addr channel 0 2440 - CONFIG_SYS_I2C_IHS_CH1 activate hardware channel 1 2441 - CONFIG_SYS_I2C_IHS_SPEED_1 speed channel 1 2442 - CONFIG_SYS_I2C_IHS_SLAVE_1 slave addr channel 1 2443 - CONFIG_SYS_I2C_IHS_CH2 activate hardware channel 2 2444 - CONFIG_SYS_I2C_IHS_SPEED_2 speed channel 2 2445 - CONFIG_SYS_I2C_IHS_SLAVE_2 slave addr channel 2 2446 - CONFIG_SYS_I2C_IHS_CH3 activate hardware channel 3 2447 - CONFIG_SYS_I2C_IHS_SPEED_3 speed channel 3 2448 - CONFIG_SYS_I2C_IHS_SLAVE_3 slave addr channel 3 2449 2450 additional defines: 2451 2452 CONFIG_SYS_NUM_I2C_BUSES 2453 Hold the number of i2c buses you want to use. If you 2454 don't use/have i2c muxes on your i2c bus, this 2455 is equal to CONFIG_SYS_NUM_I2C_ADAPTERS, and you can 2456 omit this define. 2457 2458 CONFIG_SYS_I2C_DIRECT_BUS 2459 define this, if you don't use i2c muxes on your hardware. 2460 if CONFIG_SYS_I2C_MAX_HOPS is not defined or == 0 you can 2461 omit this define. 2462 2463 CONFIG_SYS_I2C_MAX_HOPS 2464 define how many muxes are maximal consecutively connected 2465 on one i2c bus. If you not use i2c muxes, omit this 2466 define. 2467 2468 CONFIG_SYS_I2C_BUSES 2469 hold a list of buses you want to use, only used if 2470 CONFIG_SYS_I2C_DIRECT_BUS is not defined, for example 2471 a board with CONFIG_SYS_I2C_MAX_HOPS = 1 and 2472 CONFIG_SYS_NUM_I2C_BUSES = 9: 2473 2474 CONFIG_SYS_I2C_BUSES {{0, {I2C_NULL_HOP}}, \ 2475 {0, {{I2C_MUX_PCA9547, 0x70, 1}}}, \ 2476 {0, {{I2C_MUX_PCA9547, 0x70, 2}}}, \ 2477 {0, {{I2C_MUX_PCA9547, 0x70, 3}}}, \ 2478 {0, {{I2C_MUX_PCA9547, 0x70, 4}}}, \ 2479 {0, {{I2C_MUX_PCA9547, 0x70, 5}}}, \ 2480 {1, {I2C_NULL_HOP}}, \ 2481 {1, {{I2C_MUX_PCA9544, 0x72, 1}}}, \ 2482 {1, {{I2C_MUX_PCA9544, 0x72, 2}}}, \ 2483 } 2484 2485 which defines 2486 bus 0 on adapter 0 without a mux 2487 bus 1 on adapter 0 with a PCA9547 on address 0x70 port 1 2488 bus 2 on adapter 0 with a PCA9547 on address 0x70 port 2 2489 bus 3 on adapter 0 with a PCA9547 on address 0x70 port 3 2490 bus 4 on adapter 0 with a PCA9547 on address 0x70 port 4 2491 bus 5 on adapter 0 with a PCA9547 on address 0x70 port 5 2492 bus 6 on adapter 1 without a mux 2493 bus 7 on adapter 1 with a PCA9544 on address 0x72 port 1 2494 bus 8 on adapter 1 with a PCA9544 on address 0x72 port 2 2495 2496 If you do not have i2c muxes on your board, omit this define. 2497 2498- Legacy I2C Support: CONFIG_HARD_I2C 2499 2500 NOTE: It is intended to move drivers to CONFIG_SYS_I2C which 2501 provides the following compelling advantages: 2502 2503 - more than one i2c adapter is usable 2504 - approved multibus support 2505 - better i2c mux support 2506 2507 ** Please consider updating your I2C driver now. ** 2508 2509 These enable legacy I2C serial bus commands. Defining 2510 CONFIG_HARD_I2C will include the appropriate I2C driver 2511 for the selected CPU. 2512 2513 This will allow you to use i2c commands at the u-boot 2514 command line (as long as you set CONFIG_CMD_I2C in 2515 CONFIG_COMMANDS) and communicate with i2c based realtime 2516 clock chips. See common/cmd_i2c.c for a description of the 2517 command line interface. 2518 2519 CONFIG_HARD_I2C selects a hardware I2C controller. 2520 2521 There are several other quantities that must also be 2522 defined when you define CONFIG_HARD_I2C. 2523 2524 In both cases you will need to define CONFIG_SYS_I2C_SPEED 2525 to be the frequency (in Hz) at which you wish your i2c bus 2526 to run and CONFIG_SYS_I2C_SLAVE to be the address of this node (ie 2527 the CPU's i2c node address). 2528 2529 Now, the u-boot i2c code for the mpc8xx 2530 (arch/powerpc/cpu/mpc8xx/i2c.c) sets the CPU up as a master node 2531 and so its address should therefore be cleared to 0 (See, 2532 eg, MPC823e User's Manual p.16-473). So, set 2533 CONFIG_SYS_I2C_SLAVE to 0. 2534 2535 CONFIG_SYS_I2C_INIT_MPC5XXX 2536 2537 When a board is reset during an i2c bus transfer 2538 chips might think that the current transfer is still 2539 in progress. Reset the slave devices by sending start 2540 commands until the slave device responds. 2541 2542 That's all that's required for CONFIG_HARD_I2C. 2543 2544 If you use the software i2c interface (CONFIG_SYS_I2C_SOFT) 2545 then the following macros need to be defined (examples are 2546 from include/configs/lwmon.h): 2547 2548 I2C_INIT 2549 2550 (Optional). Any commands necessary to enable the I2C 2551 controller or configure ports. 2552 2553 eg: #define I2C_INIT (immr->im_cpm.cp_pbdir |= PB_SCL) 2554 2555 I2C_PORT 2556 2557 (Only for MPC8260 CPU). The I/O port to use (the code 2558 assumes both bits are on the same port). Valid values 2559 are 0..3 for ports A..D. 2560 2561 I2C_ACTIVE 2562 2563 The code necessary to make the I2C data line active 2564 (driven). If the data line is open collector, this 2565 define can be null. 2566 2567 eg: #define I2C_ACTIVE (immr->im_cpm.cp_pbdir |= PB_SDA) 2568 2569 I2C_TRISTATE 2570 2571 The code necessary to make the I2C data line tri-stated 2572 (inactive). If the data line is open collector, this 2573 define can be null. 2574 2575 eg: #define I2C_TRISTATE (immr->im_cpm.cp_pbdir &= ~PB_SDA) 2576 2577 I2C_READ 2578 2579 Code that returns true if the I2C data line is high, 2580 false if it is low. 2581 2582 eg: #define I2C_READ ((immr->im_cpm.cp_pbdat & PB_SDA) != 0) 2583 2584 I2C_SDA(bit) 2585 2586 If <bit> is true, sets the I2C data line high. If it 2587 is false, it clears it (low). 2588 2589 eg: #define I2C_SDA(bit) \ 2590 if(bit) immr->im_cpm.cp_pbdat |= PB_SDA; \ 2591 else immr->im_cpm.cp_pbdat &= ~PB_SDA 2592 2593 I2C_SCL(bit) 2594 2595 If <bit> is true, sets the I2C clock line high. If it 2596 is false, it clears it (low). 2597 2598 eg: #define I2C_SCL(bit) \ 2599 if(bit) immr->im_cpm.cp_pbdat |= PB_SCL; \ 2600 else immr->im_cpm.cp_pbdat &= ~PB_SCL 2601 2602 I2C_DELAY 2603 2604 This delay is invoked four times per clock cycle so this 2605 controls the rate of data transfer. The data rate thus 2606 is 1 / (I2C_DELAY * 4). Often defined to be something 2607 like: 2608 2609 #define I2C_DELAY udelay(2) 2610 2611 CONFIG_SOFT_I2C_GPIO_SCL / CONFIG_SOFT_I2C_GPIO_SDA 2612 2613 If your arch supports the generic GPIO framework (asm/gpio.h), 2614 then you may alternatively define the two GPIOs that are to be 2615 used as SCL / SDA. Any of the previous I2C_xxx macros will 2616 have GPIO-based defaults assigned to them as appropriate. 2617 2618 You should define these to the GPIO value as given directly to 2619 the generic GPIO functions. 2620 2621 CONFIG_SYS_I2C_INIT_BOARD 2622 2623 When a board is reset during an i2c bus transfer 2624 chips might think that the current transfer is still 2625 in progress. On some boards it is possible to access 2626 the i2c SCLK line directly, either by using the 2627 processor pin as a GPIO or by having a second pin 2628 connected to the bus. If this option is defined a 2629 custom i2c_init_board() routine in boards/xxx/board.c 2630 is run early in the boot sequence. 2631 2632 CONFIG_SYS_I2C_BOARD_LATE_INIT 2633 2634 An alternative to CONFIG_SYS_I2C_INIT_BOARD. If this option is 2635 defined a custom i2c_board_late_init() routine in 2636 boards/xxx/board.c is run AFTER the operations in i2c_init() 2637 is completed. This callpoint can be used to unreset i2c bus 2638 using CPU i2c controller register accesses for CPUs whose i2c 2639 controller provide such a method. It is called at the end of 2640 i2c_init() to allow i2c_init operations to setup the i2c bus 2641 controller on the CPU (e.g. setting bus speed & slave address). 2642 2643 CONFIG_I2CFAST (PPC405GP|PPC405EP only) 2644 2645 This option enables configuration of bi_iic_fast[] flags 2646 in u-boot bd_info structure based on u-boot environment 2647 variable "i2cfast". (see also i2cfast) 2648 2649 CONFIG_I2C_MULTI_BUS 2650 2651 This option allows the use of multiple I2C buses, each of which 2652 must have a controller. At any point in time, only one bus is 2653 active. To switch to a different bus, use the 'i2c dev' command. 2654 Note that bus numbering is zero-based. 2655 2656 CONFIG_SYS_I2C_NOPROBES 2657 2658 This option specifies a list of I2C devices that will be skipped 2659 when the 'i2c probe' command is issued. If CONFIG_I2C_MULTI_BUS 2660 is set, specify a list of bus-device pairs. Otherwise, specify 2661 a 1D array of device addresses 2662 2663 e.g. 2664 #undef CONFIG_I2C_MULTI_BUS 2665 #define CONFIG_SYS_I2C_NOPROBES {0x50,0x68} 2666 2667 will skip addresses 0x50 and 0x68 on a board with one I2C bus 2668 2669 #define CONFIG_I2C_MULTI_BUS 2670 #define CONFIG_SYS_I2C_MULTI_NOPROBES {{0,0x50},{0,0x68},{1,0x54}} 2671 2672 will skip addresses 0x50 and 0x68 on bus 0 and address 0x54 on bus 1 2673 2674 CONFIG_SYS_SPD_BUS_NUM 2675 2676 If defined, then this indicates the I2C bus number for DDR SPD. 2677 If not defined, then U-Boot assumes that SPD is on I2C bus 0. 2678 2679 CONFIG_SYS_RTC_BUS_NUM 2680 2681 If defined, then this indicates the I2C bus number for the RTC. 2682 If not defined, then U-Boot assumes that RTC is on I2C bus 0. 2683 2684 CONFIG_SYS_DTT_BUS_NUM 2685 2686 If defined, then this indicates the I2C bus number for the DTT. 2687 If not defined, then U-Boot assumes that DTT is on I2C bus 0. 2688 2689 CONFIG_SYS_I2C_DTT_ADDR: 2690 2691 If defined, specifies the I2C address of the DTT device. 2692 If not defined, then U-Boot uses predefined value for 2693 specified DTT device. 2694 2695 CONFIG_SOFT_I2C_READ_REPEATED_START 2696 2697 defining this will force the i2c_read() function in 2698 the soft_i2c driver to perform an I2C repeated start 2699 between writing the address pointer and reading the 2700 data. If this define is omitted the default behaviour 2701 of doing a stop-start sequence will be used. Most I2C 2702 devices can use either method, but some require one or 2703 the other. 2704 2705- SPI Support: CONFIG_SPI 2706 2707 Enables SPI driver (so far only tested with 2708 SPI EEPROM, also an instance works with Crystal A/D and 2709 D/As on the SACSng board) 2710 2711 CONFIG_SH_SPI 2712 2713 Enables the driver for SPI controller on SuperH. Currently 2714 only SH7757 is supported. 2715 2716 CONFIG_SPI_X 2717 2718 Enables extended (16-bit) SPI EEPROM addressing. 2719 (symmetrical to CONFIG_I2C_X) 2720 2721 CONFIG_SOFT_SPI 2722 2723 Enables a software (bit-bang) SPI driver rather than 2724 using hardware support. This is a general purpose 2725 driver that only requires three general I/O port pins 2726 (two outputs, one input) to function. If this is 2727 defined, the board configuration must define several 2728 SPI configuration items (port pins to use, etc). For 2729 an example, see include/configs/sacsng.h. 2730 2731 CONFIG_HARD_SPI 2732 2733 Enables a hardware SPI driver for general-purpose reads 2734 and writes. As with CONFIG_SOFT_SPI, the board configuration 2735 must define a list of chip-select function pointers. 2736 Currently supported on some MPC8xxx processors. For an 2737 example, see include/configs/mpc8349emds.h. 2738 2739 CONFIG_MXC_SPI 2740 2741 Enables the driver for the SPI controllers on i.MX and MXC 2742 SoCs. Currently i.MX31/35/51 are supported. 2743 2744 CONFIG_SYS_SPI_MXC_WAIT 2745 Timeout for waiting until spi transfer completed. 2746 default: (CONFIG_SYS_HZ/100) /* 10 ms */ 2747 2748- FPGA Support: CONFIG_FPGA 2749 2750 Enables FPGA subsystem. 2751 2752 CONFIG_FPGA_<vendor> 2753 2754 Enables support for specific chip vendors. 2755 (ALTERA, XILINX) 2756 2757 CONFIG_FPGA_<family> 2758 2759 Enables support for FPGA family. 2760 (SPARTAN2, SPARTAN3, VIRTEX2, CYCLONE2, ACEX1K, ACEX) 2761 2762 CONFIG_FPGA_COUNT 2763 2764 Specify the number of FPGA devices to support. 2765 2766 CONFIG_CMD_FPGA_LOADMK 2767 2768 Enable support for fpga loadmk command 2769 2770 CONFIG_CMD_FPGA_LOADP 2771 2772 Enable support for fpga loadp command - load partial bitstream 2773 2774 CONFIG_CMD_FPGA_LOADBP 2775 2776 Enable support for fpga loadbp command - load partial bitstream 2777 (Xilinx only) 2778 2779 CONFIG_SYS_FPGA_PROG_FEEDBACK 2780 2781 Enable printing of hash marks during FPGA configuration. 2782 2783 CONFIG_SYS_FPGA_CHECK_BUSY 2784 2785 Enable checks on FPGA configuration interface busy 2786 status by the configuration function. This option 2787 will require a board or device specific function to 2788 be written. 2789 2790 CONFIG_FPGA_DELAY 2791 2792 If defined, a function that provides delays in the FPGA 2793 configuration driver. 2794 2795 CONFIG_SYS_FPGA_CHECK_CTRLC 2796 Allow Control-C to interrupt FPGA configuration 2797 2798 CONFIG_SYS_FPGA_CHECK_ERROR 2799 2800 Check for configuration errors during FPGA bitfile 2801 loading. For example, abort during Virtex II 2802 configuration if the INIT_B line goes low (which 2803 indicated a CRC error). 2804 2805 CONFIG_SYS_FPGA_WAIT_INIT 2806 2807 Maximum time to wait for the INIT_B line to de-assert 2808 after PROB_B has been de-asserted during a Virtex II 2809 FPGA configuration sequence. The default time is 500 2810 ms. 2811 2812 CONFIG_SYS_FPGA_WAIT_BUSY 2813 2814 Maximum time to wait for BUSY to de-assert during 2815 Virtex II FPGA configuration. The default is 5 ms. 2816 2817 CONFIG_SYS_FPGA_WAIT_CONFIG 2818 2819 Time to wait after FPGA configuration. The default is 2820 200 ms. 2821 2822- Configuration Management: 2823 CONFIG_BUILD_TARGET 2824 2825 Some SoCs need special image types (e.g. U-Boot binary 2826 with a special header) as build targets. By defining 2827 CONFIG_BUILD_TARGET in the SoC / board header, this 2828 special image will be automatically built upon calling 2829 make / MAKEALL. 2830 2831 CONFIG_IDENT_STRING 2832 2833 If defined, this string will be added to the U-Boot 2834 version information (U_BOOT_VERSION) 2835 2836- Vendor Parameter Protection: 2837 2838 U-Boot considers the values of the environment 2839 variables "serial#" (Board Serial Number) and 2840 "ethaddr" (Ethernet Address) to be parameters that 2841 are set once by the board vendor / manufacturer, and 2842 protects these variables from casual modification by 2843 the user. Once set, these variables are read-only, 2844 and write or delete attempts are rejected. You can 2845 change this behaviour: 2846 2847 If CONFIG_ENV_OVERWRITE is #defined in your config 2848 file, the write protection for vendor parameters is 2849 completely disabled. Anybody can change or delete 2850 these parameters. 2851 2852 Alternatively, if you #define _both_ CONFIG_ETHADDR 2853 _and_ CONFIG_OVERWRITE_ETHADDR_ONCE, a default 2854 Ethernet address is installed in the environment, 2855 which can be changed exactly ONCE by the user. [The 2856 serial# is unaffected by this, i. e. it remains 2857 read-only.] 2858 2859 The same can be accomplished in a more flexible way 2860 for any variable by configuring the type of access 2861 to allow for those variables in the ".flags" variable 2862 or define CONFIG_ENV_FLAGS_LIST_STATIC. 2863 2864- Protected RAM: 2865 CONFIG_PRAM 2866 2867 Define this variable to enable the reservation of 2868 "protected RAM", i. e. RAM which is not overwritten 2869 by U-Boot. Define CONFIG_PRAM to hold the number of 2870 kB you want to reserve for pRAM. You can overwrite 2871 this default value by defining an environment 2872 variable "pram" to the number of kB you want to 2873 reserve. Note that the board info structure will 2874 still show the full amount of RAM. If pRAM is 2875 reserved, a new environment variable "mem" will 2876 automatically be defined to hold the amount of 2877 remaining RAM in a form that can be passed as boot 2878 argument to Linux, for instance like that: 2879 2880 setenv bootargs ... mem=\${mem} 2881 saveenv 2882 2883 This way you can tell Linux not to use this memory, 2884 either, which results in a memory region that will 2885 not be affected by reboots. 2886 2887 *WARNING* If your board configuration uses automatic 2888 detection of the RAM size, you must make sure that 2889 this memory test is non-destructive. So far, the 2890 following board configurations are known to be 2891 "pRAM-clean": 2892 2893 IVMS8, IVML24, SPD8xx, TQM8xxL, 2894 HERMES, IP860, RPXlite, LWMON, 2895 FLAGADM, TQM8260 2896 2897- Access to physical memory region (> 4GB) 2898 Some basic support is provided for operations on memory not 2899 normally accessible to U-Boot - e.g. some architectures 2900 support access to more than 4GB of memory on 32-bit 2901 machines using physical address extension or similar. 2902 Define CONFIG_PHYSMEM to access this basic support, which 2903 currently only supports clearing the memory. 2904 2905- Error Recovery: 2906 CONFIG_PANIC_HANG 2907 2908 Define this variable to stop the system in case of a 2909 fatal error, so that you have to reset it manually. 2910 This is probably NOT a good idea for an embedded 2911 system where you want the system to reboot 2912 automatically as fast as possible, but it may be 2913 useful during development since you can try to debug 2914 the conditions that lead to the situation. 2915 2916 CONFIG_NET_RETRY_COUNT 2917 2918 This variable defines the number of retries for 2919 network operations like ARP, RARP, TFTP, or BOOTP 2920 before giving up the operation. If not defined, a 2921 default value of 5 is used. 2922 2923 CONFIG_ARP_TIMEOUT 2924 2925 Timeout waiting for an ARP reply in milliseconds. 2926 2927 CONFIG_NFS_TIMEOUT 2928 2929 Timeout in milliseconds used in NFS protocol. 2930 If you encounter "ERROR: Cannot umount" in nfs command, 2931 try longer timeout such as 2932 #define CONFIG_NFS_TIMEOUT 10000UL 2933 2934- Command Interpreter: 2935 CONFIG_AUTO_COMPLETE 2936 2937 Enable auto completion of commands using TAB. 2938 2939 CONFIG_SYS_PROMPT_HUSH_PS2 2940 2941 This defines the secondary prompt string, which is 2942 printed when the command interpreter needs more input 2943 to complete a command. Usually "> ". 2944 2945 Note: 2946 2947 In the current implementation, the local variables 2948 space and global environment variables space are 2949 separated. Local variables are those you define by 2950 simply typing `name=value'. To access a local 2951 variable later on, you have write `$name' or 2952 `${name}'; to execute the contents of a variable 2953 directly type `$name' at the command prompt. 2954 2955 Global environment variables are those you use 2956 setenv/printenv to work with. To run a command stored 2957 in such a variable, you need to use the run command, 2958 and you must not use the '$' sign to access them. 2959 2960 To store commands and special characters in a 2961 variable, please use double quotation marks 2962 surrounding the whole text of the variable, instead 2963 of the backslashes before semicolons and special 2964 symbols. 2965 2966- Command Line Editing and History: 2967 CONFIG_CMDLINE_EDITING 2968 2969 Enable editing and History functions for interactive 2970 command line input operations 2971 2972- Default Environment: 2973 CONFIG_EXTRA_ENV_SETTINGS 2974 2975 Define this to contain any number of null terminated 2976 strings (variable = value pairs) that will be part of 2977 the default environment compiled into the boot image. 2978 2979 For example, place something like this in your 2980 board's config file: 2981 2982 #define CONFIG_EXTRA_ENV_SETTINGS \ 2983 "myvar1=value1\0" \ 2984 "myvar2=value2\0" 2985 2986 Warning: This method is based on knowledge about the 2987 internal format how the environment is stored by the 2988 U-Boot code. This is NOT an official, exported 2989 interface! Although it is unlikely that this format 2990 will change soon, there is no guarantee either. 2991 You better know what you are doing here. 2992 2993 Note: overly (ab)use of the default environment is 2994 discouraged. Make sure to check other ways to preset 2995 the environment like the "source" command or the 2996 boot command first. 2997 2998 CONFIG_ENV_VARS_UBOOT_CONFIG 2999 3000 Define this in order to add variables describing the 3001 U-Boot build configuration to the default environment. 3002 These will be named arch, cpu, board, vendor, and soc. 3003 3004 Enabling this option will cause the following to be defined: 3005 3006 - CONFIG_SYS_ARCH 3007 - CONFIG_SYS_CPU 3008 - CONFIG_SYS_BOARD 3009 - CONFIG_SYS_VENDOR 3010 - CONFIG_SYS_SOC 3011 3012 CONFIG_ENV_VARS_UBOOT_RUNTIME_CONFIG 3013 3014 Define this in order to add variables describing certain 3015 run-time determined information about the hardware to the 3016 environment. These will be named board_name, board_rev. 3017 3018 CONFIG_DELAY_ENVIRONMENT 3019 3020 Normally the environment is loaded when the board is 3021 initialised so that it is available to U-Boot. This inhibits 3022 that so that the environment is not available until 3023 explicitly loaded later by U-Boot code. With CONFIG_OF_CONTROL 3024 this is instead controlled by the value of 3025 /config/load-environment. 3026 3027- DataFlash Support: 3028 CONFIG_HAS_DATAFLASH 3029 3030 Defining this option enables DataFlash features and 3031 allows to read/write in Dataflash via the standard 3032 commands cp, md... 3033 3034- Serial Flash support 3035 CONFIG_CMD_SF 3036 3037 Defining this option enables SPI flash commands 3038 'sf probe/read/write/erase/update'. 3039 3040 Usage requires an initial 'probe' to define the serial 3041 flash parameters, followed by read/write/erase/update 3042 commands. 3043 3044 The following defaults may be provided by the platform 3045 to handle the common case when only a single serial 3046 flash is present on the system. 3047 3048 CONFIG_SF_DEFAULT_BUS Bus identifier 3049 CONFIG_SF_DEFAULT_CS Chip-select 3050 CONFIG_SF_DEFAULT_MODE (see include/spi.h) 3051 CONFIG_SF_DEFAULT_SPEED in Hz 3052 3053 CONFIG_CMD_SF_TEST 3054 3055 Define this option to include a destructive SPI flash 3056 test ('sf test'). 3057 3058 CONFIG_SPI_FLASH_BAR Ban/Extended Addr Reg 3059 3060 Define this option to use the Bank addr/Extended addr 3061 support on SPI flashes which has size > 16Mbytes. 3062 3063 CONFIG_SF_DUAL_FLASH Dual flash memories 3064 3065 Define this option to use dual flash support where two flash 3066 memories can be connected with a given cs line. 3067 Currently Xilinx Zynq qspi supports these type of connections. 3068 3069 CONFIG_SYS_SPI_ST_ENABLE_WP_PIN 3070 enable the W#/Vpp signal to disable writing to the status 3071 register on ST MICRON flashes like the N25Q128. 3072 The status register write enable/disable bit, combined with 3073 the W#/VPP signal provides hardware data protection for the 3074 device as follows: When the enable/disable bit is set to 1, 3075 and the W#/VPP signal is driven LOW, the status register 3076 nonvolatile bits become read-only and the WRITE STATUS REGISTER 3077 operation will not execute. The only way to exit this 3078 hardware-protected mode is to drive W#/VPP HIGH. 3079 3080- SystemACE Support: 3081 CONFIG_SYSTEMACE 3082 3083 Adding this option adds support for Xilinx SystemACE 3084 chips attached via some sort of local bus. The address 3085 of the chip must also be defined in the 3086 CONFIG_SYS_SYSTEMACE_BASE macro. For example: 3087 3088 #define CONFIG_SYSTEMACE 3089 #define CONFIG_SYS_SYSTEMACE_BASE 0xf0000000 3090 3091 When SystemACE support is added, the "ace" device type 3092 becomes available to the fat commands, i.e. fatls. 3093 3094- TFTP Fixed UDP Port: 3095 CONFIG_TFTP_PORT 3096 3097 If this is defined, the environment variable tftpsrcp 3098 is used to supply the TFTP UDP source port value. 3099 If tftpsrcp isn't defined, the normal pseudo-random port 3100 number generator is used. 3101 3102 Also, the environment variable tftpdstp is used to supply 3103 the TFTP UDP destination port value. If tftpdstp isn't 3104 defined, the normal port 69 is used. 3105 3106 The purpose for tftpsrcp is to allow a TFTP server to 3107 blindly start the TFTP transfer using the pre-configured 3108 target IP address and UDP port. This has the effect of 3109 "punching through" the (Windows XP) firewall, allowing 3110 the remainder of the TFTP transfer to proceed normally. 3111 A better solution is to properly configure the firewall, 3112 but sometimes that is not allowed. 3113 3114- Hashing support: 3115 CONFIG_CMD_HASH 3116 3117 This enables a generic 'hash' command which can produce 3118 hashes / digests from a few algorithms (e.g. SHA1, SHA256). 3119 3120 CONFIG_HASH_VERIFY 3121 3122 Enable the hash verify command (hash -v). This adds to code 3123 size a little. 3124 3125 CONFIG_SHA1 - This option enables support of hashing using SHA1 3126 algorithm. The hash is calculated in software. 3127 CONFIG_SHA256 - This option enables support of hashing using 3128 SHA256 algorithm. The hash is calculated in software. 3129 CONFIG_SHA_HW_ACCEL - This option enables hardware acceleration 3130 for SHA1/SHA256 hashing. 3131 This affects the 'hash' command and also the 3132 hash_lookup_algo() function. 3133 CONFIG_SHA_PROG_HW_ACCEL - This option enables 3134 hardware-acceleration for SHA1/SHA256 progressive hashing. 3135 Data can be streamed in a block at a time and the hashing 3136 is performed in hardware. 3137 3138 Note: There is also a sha1sum command, which should perhaps 3139 be deprecated in favour of 'hash sha1'. 3140 3141- Freescale i.MX specific commands: 3142 CONFIG_CMD_HDMIDETECT 3143 This enables 'hdmidet' command which returns true if an 3144 HDMI monitor is detected. This command is i.MX 6 specific. 3145 3146 CONFIG_CMD_BMODE 3147 This enables the 'bmode' (bootmode) command for forcing 3148 a boot from specific media. 3149 3150 This is useful for forcing the ROM's usb downloader to 3151 activate upon a watchdog reset which is nice when iterating 3152 on U-Boot. Using the reset button or running bmode normal 3153 will set it back to normal. This command currently 3154 supports i.MX53 and i.MX6. 3155 3156- Signing support: 3157 CONFIG_RSA 3158 3159 This enables the RSA algorithm used for FIT image verification 3160 in U-Boot. See doc/uImage.FIT/signature.txt for more information. 3161 3162 The Modular Exponentiation algorithm in RSA is implemented using 3163 driver model. So CONFIG_DM needs to be enabled by default for this 3164 library to function. 3165 3166 The signing part is build into mkimage regardless of this 3167 option. The software based modular exponentiation is built into 3168 mkimage irrespective of this option. 3169 3170- bootcount support: 3171 CONFIG_BOOTCOUNT_LIMIT 3172 3173 This enables the bootcounter support, see: 3174 http://www.denx.de/wiki/DULG/UBootBootCountLimit 3175 3176 CONFIG_AT91SAM9XE 3177 enable special bootcounter support on at91sam9xe based boards. 3178 CONFIG_BLACKFIN 3179 enable special bootcounter support on blackfin based boards. 3180 CONFIG_SOC_DA8XX 3181 enable special bootcounter support on da850 based boards. 3182 CONFIG_BOOTCOUNT_RAM 3183 enable support for the bootcounter in RAM 3184 CONFIG_BOOTCOUNT_I2C 3185 enable support for the bootcounter on an i2c (like RTC) device. 3186 CONFIG_SYS_I2C_RTC_ADDR = i2c chip address 3187 CONFIG_SYS_BOOTCOUNT_ADDR = i2c addr which is used for 3188 the bootcounter. 3189 CONFIG_BOOTCOUNT_ALEN = address len 3190 3191- Show boot progress: 3192 CONFIG_SHOW_BOOT_PROGRESS 3193 3194 Defining this option allows to add some board- 3195 specific code (calling a user-provided function 3196 "show_boot_progress(int)") that enables you to show 3197 the system's boot progress on some display (for 3198 example, some LED's) on your board. At the moment, 3199 the following checkpoints are implemented: 3200 3201- Detailed boot stage timing 3202 CONFIG_BOOTSTAGE 3203 Define this option to get detailed timing of each stage 3204 of the boot process. 3205 3206 CONFIG_BOOTSTAGE_USER_COUNT 3207 This is the number of available user bootstage records. 3208 Each time you call bootstage_mark(BOOTSTAGE_ID_ALLOC, ...) 3209 a new ID will be allocated from this stash. If you exceed 3210 the limit, recording will stop. 3211 3212 CONFIG_BOOTSTAGE_REPORT 3213 Define this to print a report before boot, similar to this: 3214 3215 Timer summary in microseconds: 3216 Mark Elapsed Stage 3217 0 0 reset 3218 3,575,678 3,575,678 board_init_f start 3219 3,575,695 17 arch_cpu_init A9 3220 3,575,777 82 arch_cpu_init done 3221 3,659,598 83,821 board_init_r start 3222 3,910,375 250,777 main_loop 3223 29,916,167 26,005,792 bootm_start 3224 30,361,327 445,160 start_kernel 3225 3226 CONFIG_CMD_BOOTSTAGE 3227 Add a 'bootstage' command which supports printing a report 3228 and un/stashing of bootstage data. 3229 3230 CONFIG_BOOTSTAGE_FDT 3231 Stash the bootstage information in the FDT. A root 'bootstage' 3232 node is created with each bootstage id as a child. Each child 3233 has a 'name' property and either 'mark' containing the 3234 mark time in microsecond, or 'accum' containing the 3235 accumulated time for that bootstage id in microseconds. 3236 For example: 3237 3238 bootstage { 3239 154 { 3240 name = "board_init_f"; 3241 mark = <3575678>; 3242 }; 3243 170 { 3244 name = "lcd"; 3245 accum = <33482>; 3246 }; 3247 }; 3248 3249 Code in the Linux kernel can find this in /proc/devicetree. 3250 3251Legacy uImage format: 3252 3253 Arg Where When 3254 1 common/cmd_bootm.c before attempting to boot an image 3255 -1 common/cmd_bootm.c Image header has bad magic number 3256 2 common/cmd_bootm.c Image header has correct magic number 3257 -2 common/cmd_bootm.c Image header has bad checksum 3258 3 common/cmd_bootm.c Image header has correct checksum 3259 -3 common/cmd_bootm.c Image data has bad checksum 3260 4 common/cmd_bootm.c Image data has correct checksum 3261 -4 common/cmd_bootm.c Image is for unsupported architecture 3262 5 common/cmd_bootm.c Architecture check OK 3263 -5 common/cmd_bootm.c Wrong Image Type (not kernel, multi) 3264 6 common/cmd_bootm.c Image Type check OK 3265 -6 common/cmd_bootm.c gunzip uncompression error 3266 -7 common/cmd_bootm.c Unimplemented compression type 3267 7 common/cmd_bootm.c Uncompression OK 3268 8 common/cmd_bootm.c No uncompress/copy overwrite error 3269 -9 common/cmd_bootm.c Unsupported OS (not Linux, BSD, VxWorks, QNX) 3270 3271 9 common/image.c Start initial ramdisk verification 3272 -10 common/image.c Ramdisk header has bad magic number 3273 -11 common/image.c Ramdisk header has bad checksum 3274 10 common/image.c Ramdisk header is OK 3275 -12 common/image.c Ramdisk data has bad checksum 3276 11 common/image.c Ramdisk data has correct checksum 3277 12 common/image.c Ramdisk verification complete, start loading 3278 -13 common/image.c Wrong Image Type (not PPC Linux ramdisk) 3279 13 common/image.c Start multifile image verification 3280 14 common/image.c No initial ramdisk, no multifile, continue. 3281 3282 15 arch/<arch>/lib/bootm.c All preparation done, transferring control to OS 3283 3284 -30 arch/powerpc/lib/board.c Fatal error, hang the system 3285 -31 post/post.c POST test failed, detected by post_output_backlog() 3286 -32 post/post.c POST test failed, detected by post_run_single() 3287 3288 34 common/cmd_doc.c before loading a Image from a DOC device 3289 -35 common/cmd_doc.c Bad usage of "doc" command 3290 35 common/cmd_doc.c correct usage of "doc" command 3291 -36 common/cmd_doc.c No boot device 3292 36 common/cmd_doc.c correct boot device 3293 -37 common/cmd_doc.c Unknown Chip ID on boot device 3294 37 common/cmd_doc.c correct chip ID found, device available 3295 -38 common/cmd_doc.c Read Error on boot device 3296 38 common/cmd_doc.c reading Image header from DOC device OK 3297 -39 common/cmd_doc.c Image header has bad magic number 3298 39 common/cmd_doc.c Image header has correct magic number 3299 -40 common/cmd_doc.c Error reading Image from DOC device 3300 40 common/cmd_doc.c Image header has correct magic number 3301 41 common/cmd_ide.c before loading a Image from a IDE device 3302 -42 common/cmd_ide.c Bad usage of "ide" command 3303 42 common/cmd_ide.c correct usage of "ide" command 3304 -43 common/cmd_ide.c No boot device 3305 43 common/cmd_ide.c boot device found 3306 -44 common/cmd_ide.c Device not available 3307 44 common/cmd_ide.c Device available 3308 -45 common/cmd_ide.c wrong partition selected 3309 45 common/cmd_ide.c partition selected 3310 -46 common/cmd_ide.c Unknown partition table 3311 46 common/cmd_ide.c valid partition table found 3312 -47 common/cmd_ide.c Invalid partition type 3313 47 common/cmd_ide.c correct partition type 3314 -48 common/cmd_ide.c Error reading Image Header on boot device 3315 48 common/cmd_ide.c reading Image Header from IDE device OK 3316 -49 common/cmd_ide.c Image header has bad magic number 3317 49 common/cmd_ide.c Image header has correct magic number 3318 -50 common/cmd_ide.c Image header has bad checksum 3319 50 common/cmd_ide.c Image header has correct checksum 3320 -51 common/cmd_ide.c Error reading Image from IDE device 3321 51 common/cmd_ide.c reading Image from IDE device OK 3322 52 common/cmd_nand.c before loading a Image from a NAND device 3323 -53 common/cmd_nand.c Bad usage of "nand" command 3324 53 common/cmd_nand.c correct usage of "nand" command 3325 -54 common/cmd_nand.c No boot device 3326 54 common/cmd_nand.c boot device found 3327 -55 common/cmd_nand.c Unknown Chip ID on boot device 3328 55 common/cmd_nand.c correct chip ID found, device available 3329 -56 common/cmd_nand.c Error reading Image Header on boot device 3330 56 common/cmd_nand.c reading Image Header from NAND device OK 3331 -57 common/cmd_nand.c Image header has bad magic number 3332 57 common/cmd_nand.c Image header has correct magic number 3333 -58 common/cmd_nand.c Error reading Image from NAND device 3334 58 common/cmd_nand.c reading Image from NAND device OK 3335 3336 -60 common/env_common.c Environment has a bad CRC, using default 3337 3338 64 net/eth.c starting with Ethernet configuration. 3339 -64 net/eth.c no Ethernet found. 3340 65 net/eth.c Ethernet found. 3341 3342 -80 common/cmd_net.c usage wrong 3343 80 common/cmd_net.c before calling NetLoop() 3344 -81 common/cmd_net.c some error in NetLoop() occurred 3345 81 common/cmd_net.c NetLoop() back without error 3346 -82 common/cmd_net.c size == 0 (File with size 0 loaded) 3347 82 common/cmd_net.c trying automatic boot 3348 83 common/cmd_net.c running "source" command 3349 -83 common/cmd_net.c some error in automatic boot or "source" command 3350 84 common/cmd_net.c end without errors 3351 3352FIT uImage format: 3353 3354 Arg Where When 3355 100 common/cmd_bootm.c Kernel FIT Image has correct format 3356 -100 common/cmd_bootm.c Kernel FIT Image has incorrect format 3357 101 common/cmd_bootm.c No Kernel subimage unit name, using configuration 3358 -101 common/cmd_bootm.c Can't get configuration for kernel subimage 3359 102 common/cmd_bootm.c Kernel unit name specified 3360 -103 common/cmd_bootm.c Can't get kernel subimage node offset 3361 103 common/cmd_bootm.c Found configuration node 3362 104 common/cmd_bootm.c Got kernel subimage node offset 3363 -104 common/cmd_bootm.c Kernel subimage hash verification failed 3364 105 common/cmd_bootm.c Kernel subimage hash verification OK 3365 -105 common/cmd_bootm.c Kernel subimage is for unsupported architecture 3366 106 common/cmd_bootm.c Architecture check OK 3367 -106 common/cmd_bootm.c Kernel subimage has wrong type 3368 107 common/cmd_bootm.c Kernel subimage type OK 3369 -107 common/cmd_bootm.c Can't get kernel subimage data/size 3370 108 common/cmd_bootm.c Got kernel subimage data/size 3371 -108 common/cmd_bootm.c Wrong image type (not legacy, FIT) 3372 -109 common/cmd_bootm.c Can't get kernel subimage type 3373 -110 common/cmd_bootm.c Can't get kernel subimage comp 3374 -111 common/cmd_bootm.c Can't get kernel subimage os 3375 -112 common/cmd_bootm.c Can't get kernel subimage load address 3376 -113 common/cmd_bootm.c Image uncompress/copy overwrite error 3377 3378 120 common/image.c Start initial ramdisk verification 3379 -120 common/image.c Ramdisk FIT image has incorrect format 3380 121 common/image.c Ramdisk FIT image has correct format 3381 122 common/image.c No ramdisk subimage unit name, using configuration 3382 -122 common/image.c Can't get configuration for ramdisk subimage 3383 123 common/image.c Ramdisk unit name specified 3384 -124 common/image.c Can't get ramdisk subimage node offset 3385 125 common/image.c Got ramdisk subimage node offset 3386 -125 common/image.c Ramdisk subimage hash verification failed 3387 126 common/image.c Ramdisk subimage hash verification OK 3388 -126 common/image.c Ramdisk subimage for unsupported architecture 3389 127 common/image.c Architecture check OK 3390 -127 common/image.c Can't get ramdisk subimage data/size 3391 128 common/image.c Got ramdisk subimage data/size 3392 129 common/image.c Can't get ramdisk load address 3393 -129 common/image.c Got ramdisk load address 3394 3395 -130 common/cmd_doc.c Incorrect FIT image format 3396 131 common/cmd_doc.c FIT image format OK 3397 3398 -140 common/cmd_ide.c Incorrect FIT image format 3399 141 common/cmd_ide.c FIT image format OK 3400 3401 -150 common/cmd_nand.c Incorrect FIT image format 3402 151 common/cmd_nand.c FIT image format OK 3403 3404- legacy image format: 3405 CONFIG_IMAGE_FORMAT_LEGACY 3406 enables the legacy image format support in U-Boot. 3407 3408 Default: 3409 enabled if CONFIG_FIT_SIGNATURE is not defined. 3410 3411 CONFIG_DISABLE_IMAGE_LEGACY 3412 disable the legacy image format 3413 3414 This define is introduced, as the legacy image format is 3415 enabled per default for backward compatibility. 3416 3417- FIT image support: 3418 CONFIG_FIT 3419 Enable support for the FIT uImage format. 3420 3421 CONFIG_FIT_BEST_MATCH 3422 When no configuration is explicitly selected, default to the 3423 one whose fdt's compatibility field best matches that of 3424 U-Boot itself. A match is considered "best" if it matches the 3425 most specific compatibility entry of U-Boot's fdt's root node. 3426 The order of entries in the configuration's fdt is ignored. 3427 3428 CONFIG_FIT_SIGNATURE 3429 This option enables signature verification of FIT uImages, 3430 using a hash signed and verified using RSA. If 3431 CONFIG_SHA_PROG_HW_ACCEL is defined, i.e support for progressive 3432 hashing is available using hardware, RSA library will use it. 3433 See doc/uImage.FIT/signature.txt for more details. 3434 3435 WARNING: When relying on signed FIT images with required 3436 signature check the legacy image format is default 3437 disabled. If a board need legacy image format support 3438 enable this through CONFIG_IMAGE_FORMAT_LEGACY 3439 3440 CONFIG_FIT_DISABLE_SHA256 3441 Supporting SHA256 hashes has quite an impact on binary size. 3442 For constrained systems sha256 hash support can be disabled 3443 with this option. 3444 3445- Standalone program support: 3446 CONFIG_STANDALONE_LOAD_ADDR 3447 3448 This option defines a board specific value for the 3449 address where standalone program gets loaded, thus 3450 overwriting the architecture dependent default 3451 settings. 3452 3453- Frame Buffer Address: 3454 CONFIG_FB_ADDR 3455 3456 Define CONFIG_FB_ADDR if you want to use specific 3457 address for frame buffer. This is typically the case 3458 when using a graphics controller has separate video 3459 memory. U-Boot will then place the frame buffer at 3460 the given address instead of dynamically reserving it 3461 in system RAM by calling lcd_setmem(), which grabs 3462 the memory for the frame buffer depending on the 3463 configured panel size. 3464 3465 Please see board_init_f function. 3466 3467- Automatic software updates via TFTP server 3468 CONFIG_UPDATE_TFTP 3469 CONFIG_UPDATE_TFTP_CNT_MAX 3470 CONFIG_UPDATE_TFTP_MSEC_MAX 3471 3472 These options enable and control the auto-update feature; 3473 for a more detailed description refer to doc/README.update. 3474 3475- MTD Support (mtdparts command, UBI support) 3476 CONFIG_MTD_DEVICE 3477 3478 Adds the MTD device infrastructure from the Linux kernel. 3479 Needed for mtdparts command support. 3480 3481 CONFIG_MTD_PARTITIONS 3482 3483 Adds the MTD partitioning infrastructure from the Linux 3484 kernel. Needed for UBI support. 3485 3486- UBI support 3487 CONFIG_CMD_UBI 3488 3489 Adds commands for interacting with MTD partitions formatted 3490 with the UBI flash translation layer 3491 3492 Requires also defining CONFIG_RBTREE 3493 3494 CONFIG_UBI_SILENCE_MSG 3495 3496 Make the verbose messages from UBI stop printing. This leaves 3497 warnings and errors enabled. 3498 3499 3500 CONFIG_MTD_UBI_WL_THRESHOLD 3501 This parameter defines the maximum difference between the highest 3502 erase counter value and the lowest erase counter value of eraseblocks 3503 of UBI devices. When this threshold is exceeded, UBI starts performing 3504 wear leveling by means of moving data from eraseblock with low erase 3505 counter to eraseblocks with high erase counter. 3506 3507 The default value should be OK for SLC NAND flashes, NOR flashes and 3508 other flashes which have eraseblock life-cycle 100000 or more. 3509 However, in case of MLC NAND flashes which typically have eraseblock 3510 life-cycle less than 10000, the threshold should be lessened (e.g., 3511 to 128 or 256, although it does not have to be power of 2). 3512 3513 default: 4096 3514 3515 CONFIG_MTD_UBI_BEB_LIMIT 3516 This option specifies the maximum bad physical eraseblocks UBI 3517 expects on the MTD device (per 1024 eraseblocks). If the 3518 underlying flash does not admit of bad eraseblocks (e.g. NOR 3519 flash), this value is ignored. 3520 3521 NAND datasheets often specify the minimum and maximum NVM 3522 (Number of Valid Blocks) for the flashes' endurance lifetime. 3523 The maximum expected bad eraseblocks per 1024 eraseblocks 3524 then can be calculated as "1024 * (1 - MinNVB / MaxNVB)", 3525 which gives 20 for most NANDs (MaxNVB is basically the total 3526 count of eraseblocks on the chip). 3527 3528 To put it differently, if this value is 20, UBI will try to 3529 reserve about 1.9% of physical eraseblocks for bad blocks 3530 handling. And that will be 1.9% of eraseblocks on the entire 3531 NAND chip, not just the MTD partition UBI attaches. This means 3532 that if you have, say, a NAND flash chip admits maximum 40 bad 3533 eraseblocks, and it is split on two MTD partitions of the same 3534 size, UBI will reserve 40 eraseblocks when attaching a 3535 partition. 3536 3537 default: 20 3538 3539 CONFIG_MTD_UBI_FASTMAP 3540 Fastmap is a mechanism which allows attaching an UBI device 3541 in nearly constant time. Instead of scanning the whole MTD device it 3542 only has to locate a checkpoint (called fastmap) on the device. 3543 The on-flash fastmap contains all information needed to attach 3544 the device. Using fastmap makes only sense on large devices where 3545 attaching by scanning takes long. UBI will not automatically install 3546 a fastmap on old images, but you can set the UBI parameter 3547 CONFIG_MTD_UBI_FASTMAP_AUTOCONVERT to 1 if you want so. Please note 3548 that fastmap-enabled images are still usable with UBI implementations 3549 without fastmap support. On typical flash devices the whole fastmap 3550 fits into one PEB. UBI will reserve PEBs to hold two fastmaps. 3551 3552 CONFIG_MTD_UBI_FASTMAP_AUTOCONVERT 3553 Set this parameter to enable fastmap automatically on images 3554 without a fastmap. 3555 default: 0 3556 3557- UBIFS support 3558 CONFIG_CMD_UBIFS 3559 3560 Adds commands for interacting with UBI volumes formatted as 3561 UBIFS. UBIFS is read-only in u-boot. 3562 3563 Requires UBI support as well as CONFIG_LZO 3564 3565 CONFIG_UBIFS_SILENCE_MSG 3566 3567 Make the verbose messages from UBIFS stop printing. This leaves 3568 warnings and errors enabled. 3569 3570- SPL framework 3571 CONFIG_SPL 3572 Enable building of SPL globally. 3573 3574 CONFIG_SPL_LDSCRIPT 3575 LDSCRIPT for linking the SPL binary. 3576 3577 CONFIG_SPL_MAX_FOOTPRINT 3578 Maximum size in memory allocated to the SPL, BSS included. 3579 When defined, the linker checks that the actual memory 3580 used by SPL from _start to __bss_end does not exceed it. 3581 CONFIG_SPL_MAX_FOOTPRINT and CONFIG_SPL_BSS_MAX_SIZE 3582 must not be both defined at the same time. 3583 3584 CONFIG_SPL_MAX_SIZE 3585 Maximum size of the SPL image (text, data, rodata, and 3586 linker lists sections), BSS excluded. 3587 When defined, the linker checks that the actual size does 3588 not exceed it. 3589 3590 CONFIG_SPL_TEXT_BASE 3591 TEXT_BASE for linking the SPL binary. 3592 3593 CONFIG_SPL_RELOC_TEXT_BASE 3594 Address to relocate to. If unspecified, this is equal to 3595 CONFIG_SPL_TEXT_BASE (i.e. no relocation is done). 3596 3597 CONFIG_SPL_BSS_START_ADDR 3598 Link address for the BSS within the SPL binary. 3599 3600 CONFIG_SPL_BSS_MAX_SIZE 3601 Maximum size in memory allocated to the SPL BSS. 3602 When defined, the linker checks that the actual memory used 3603 by SPL from __bss_start to __bss_end does not exceed it. 3604 CONFIG_SPL_MAX_FOOTPRINT and CONFIG_SPL_BSS_MAX_SIZE 3605 must not be both defined at the same time. 3606 3607 CONFIG_SPL_STACK 3608 Adress of the start of the stack SPL will use 3609 3610 CONFIG_SPL_RELOC_STACK 3611 Adress of the start of the stack SPL will use after 3612 relocation. If unspecified, this is equal to 3613 CONFIG_SPL_STACK. 3614 3615 CONFIG_SYS_SPL_MALLOC_START 3616 Starting address of the malloc pool used in SPL. 3617 3618 CONFIG_SYS_SPL_MALLOC_SIZE 3619 The size of the malloc pool used in SPL. 3620 3621 CONFIG_SPL_FRAMEWORK 3622 Enable the SPL framework under common/. This framework 3623 supports MMC, NAND and YMODEM loading of U-Boot and NAND 3624 NAND loading of the Linux Kernel. 3625 3626 CONFIG_SPL_OS_BOOT 3627 Enable booting directly to an OS from SPL. 3628 See also: doc/README.falcon 3629 3630 CONFIG_SPL_DISPLAY_PRINT 3631 For ARM, enable an optional function to print more information 3632 about the running system. 3633 3634 CONFIG_SPL_INIT_MINIMAL 3635 Arch init code should be built for a very small image 3636 3637 CONFIG_SPL_LIBCOMMON_SUPPORT 3638 Support for common/libcommon.o in SPL binary 3639 3640 CONFIG_SPL_LIBDISK_SUPPORT 3641 Support for disk/libdisk.o in SPL binary 3642 3643 CONFIG_SPL_I2C_SUPPORT 3644 Support for drivers/i2c/libi2c.o in SPL binary 3645 3646 CONFIG_SPL_GPIO_SUPPORT 3647 Support for drivers/gpio/libgpio.o in SPL binary 3648 3649 CONFIG_SPL_MMC_SUPPORT 3650 Support for drivers/mmc/libmmc.o in SPL binary 3651 3652 CONFIG_SYS_MMCSD_RAW_MODE_U_BOOT_SECTOR, 3653 CONFIG_SYS_U_BOOT_MAX_SIZE_SECTORS, 3654 Address and partition on the MMC to load U-Boot from 3655 when the MMC is being used in raw mode. 3656 3657 CONFIG_SYS_MMCSD_RAW_MODE_U_BOOT_PARTITION 3658 Partition on the MMC to load U-Boot from when the MMC is being 3659 used in raw mode 3660 3661 CONFIG_SYS_MMCSD_RAW_MODE_KERNEL_SECTOR 3662 Sector to load kernel uImage from when MMC is being 3663 used in raw mode (for Falcon mode) 3664 3665 CONFIG_SYS_MMCSD_RAW_MODE_ARGS_SECTOR, 3666 CONFIG_SYS_MMCSD_RAW_MODE_ARGS_SECTORS 3667 Sector and number of sectors to load kernel argument 3668 parameters from when MMC is being used in raw mode 3669 (for falcon mode) 3670 3671 CONFIG_SYS_MMCSD_FS_BOOT_PARTITION 3672 Partition on the MMC to load U-Boot from when the MMC is being 3673 used in fs mode 3674 3675 CONFIG_SPL_FAT_SUPPORT 3676 Support for fs/fat/libfat.o in SPL binary 3677 3678 CONFIG_SPL_EXT_SUPPORT 3679 Support for EXT filesystem in SPL binary 3680 3681 CONFIG_SPL_FS_LOAD_PAYLOAD_NAME 3682 Filename to read to load U-Boot when reading from filesystem 3683 3684 CONFIG_SPL_FS_LOAD_KERNEL_NAME 3685 Filename to read to load kernel uImage when reading 3686 from filesystem (for Falcon mode) 3687 3688 CONFIG_SPL_FS_LOAD_ARGS_NAME 3689 Filename to read to load kernel argument parameters 3690 when reading from filesystem (for Falcon mode) 3691 3692 CONFIG_SPL_MPC83XX_WAIT_FOR_NAND 3693 Set this for NAND SPL on PPC mpc83xx targets, so that 3694 start.S waits for the rest of the SPL to load before 3695 continuing (the hardware starts execution after just 3696 loading the first page rather than the full 4K). 3697 3698 CONFIG_SPL_SKIP_RELOCATE 3699 Avoid SPL relocation 3700 3701 CONFIG_SPL_NAND_BASE 3702 Include nand_base.c in the SPL. Requires 3703 CONFIG_SPL_NAND_DRIVERS. 3704 3705 CONFIG_SPL_NAND_DRIVERS 3706 SPL uses normal NAND drivers, not minimal drivers. 3707 3708 CONFIG_SPL_NAND_ECC 3709 Include standard software ECC in the SPL 3710 3711 CONFIG_SPL_NAND_SIMPLE 3712 Support for NAND boot using simple NAND drivers that 3713 expose the cmd_ctrl() interface. 3714 3715 CONFIG_SPL_MTD_SUPPORT 3716 Support for the MTD subsystem within SPL. Useful for 3717 environment on NAND support within SPL. 3718 3719 CONFIG_SPL_NAND_RAW_ONLY 3720 Support to boot only raw u-boot.bin images. Use this only 3721 if you need to save space. 3722 3723 CONFIG_SPL_MPC8XXX_INIT_DDR_SUPPORT 3724 Set for the SPL on PPC mpc8xxx targets, support for 3725 drivers/ddr/fsl/libddr.o in SPL binary. 3726 3727 CONFIG_SPL_COMMON_INIT_DDR 3728 Set for common ddr init with serial presence detect in 3729 SPL binary. 3730 3731 CONFIG_SYS_NAND_5_ADDR_CYCLE, CONFIG_SYS_NAND_PAGE_COUNT, 3732 CONFIG_SYS_NAND_PAGE_SIZE, CONFIG_SYS_NAND_OOBSIZE, 3733 CONFIG_SYS_NAND_BLOCK_SIZE, CONFIG_SYS_NAND_BAD_BLOCK_POS, 3734 CONFIG_SYS_NAND_ECCPOS, CONFIG_SYS_NAND_ECCSIZE, 3735 CONFIG_SYS_NAND_ECCBYTES 3736 Defines the size and behavior of the NAND that SPL uses 3737 to read U-Boot 3738 3739 CONFIG_SPL_NAND_BOOT 3740 Add support NAND boot 3741 3742 CONFIG_SYS_NAND_U_BOOT_OFFS 3743 Location in NAND to read U-Boot from 3744 3745 CONFIG_SYS_NAND_U_BOOT_DST 3746 Location in memory to load U-Boot to 3747 3748 CONFIG_SYS_NAND_U_BOOT_SIZE 3749 Size of image to load 3750 3751 CONFIG_SYS_NAND_U_BOOT_START 3752 Entry point in loaded image to jump to 3753 3754 CONFIG_SYS_NAND_HW_ECC_OOBFIRST 3755 Define this if you need to first read the OOB and then the 3756 data. This is used, for example, on davinci platforms. 3757 3758 CONFIG_SPL_OMAP3_ID_NAND 3759 Support for an OMAP3-specific set of functions to return the 3760 ID and MFR of the first attached NAND chip, if present. 3761 3762 CONFIG_SPL_SERIAL_SUPPORT 3763 Support for drivers/serial/libserial.o in SPL binary 3764 3765 CONFIG_SPL_SPI_FLASH_SUPPORT 3766 Support for drivers/mtd/spi/libspi_flash.o in SPL binary 3767 3768 CONFIG_SPL_SPI_SUPPORT 3769 Support for drivers/spi/libspi.o in SPL binary 3770 3771 CONFIG_SPL_RAM_DEVICE 3772 Support for running image already present in ram, in SPL binary 3773 3774 CONFIG_SPL_LIBGENERIC_SUPPORT 3775 Support for lib/libgeneric.o in SPL binary 3776 3777 CONFIG_SPL_ENV_SUPPORT 3778 Support for the environment operating in SPL binary 3779 3780 CONFIG_SPL_NET_SUPPORT 3781 Support for the net/libnet.o in SPL binary. 3782 It conflicts with SPL env from storage medium specified by 3783 CONFIG_ENV_IS_xxx but CONFIG_ENV_IS_NOWHERE 3784 3785 CONFIG_SPL_PAD_TO 3786 Image offset to which the SPL should be padded before appending 3787 the SPL payload. By default, this is defined as 3788 CONFIG_SPL_MAX_SIZE, or 0 if CONFIG_SPL_MAX_SIZE is undefined. 3789 CONFIG_SPL_PAD_TO must be either 0, meaning to append the SPL 3790 payload without any padding, or >= CONFIG_SPL_MAX_SIZE. 3791 3792 CONFIG_SPL_TARGET 3793 Final target image containing SPL and payload. Some SPLs 3794 use an arch-specific makefile fragment instead, for 3795 example if more than one image needs to be produced. 3796 3797 CONFIG_FIT_SPL_PRINT 3798 Printing information about a FIT image adds quite a bit of 3799 code to SPL. So this is normally disabled in SPL. Use this 3800 option to re-enable it. This will affect the output of the 3801 bootm command when booting a FIT image. 3802 3803- TPL framework 3804 CONFIG_TPL 3805 Enable building of TPL globally. 3806 3807 CONFIG_TPL_PAD_TO 3808 Image offset to which the TPL should be padded before appending 3809 the TPL payload. By default, this is defined as 3810 CONFIG_SPL_MAX_SIZE, or 0 if CONFIG_SPL_MAX_SIZE is undefined. 3811 CONFIG_SPL_PAD_TO must be either 0, meaning to append the SPL 3812 payload without any padding, or >= CONFIG_SPL_MAX_SIZE. 3813 3814Modem Support: 3815-------------- 3816 3817[so far only for SMDK2400 boards] 3818 3819- Modem support enable: 3820 CONFIG_MODEM_SUPPORT 3821 3822- RTS/CTS Flow control enable: 3823 CONFIG_HWFLOW 3824 3825- Modem debug support: 3826 CONFIG_MODEM_SUPPORT_DEBUG 3827 3828 Enables debugging stuff (char screen[1024], dbg()) 3829 for modem support. Useful only with BDI2000. 3830 3831- Interrupt support (PPC): 3832 3833 There are common interrupt_init() and timer_interrupt() 3834 for all PPC archs. interrupt_init() calls interrupt_init_cpu() 3835 for CPU specific initialization. interrupt_init_cpu() 3836 should set decrementer_count to appropriate value. If 3837 CPU resets decrementer automatically after interrupt 3838 (ppc4xx) it should set decrementer_count to zero. 3839 timer_interrupt() calls timer_interrupt_cpu() for CPU 3840 specific handling. If board has watchdog / status_led 3841 / other_activity_monitor it works automatically from 3842 general timer_interrupt(). 3843 3844- General: 3845 3846 In the target system modem support is enabled when a 3847 specific key (key combination) is pressed during 3848 power-on. Otherwise U-Boot will boot normally 3849 (autoboot). The key_pressed() function is called from 3850 board_init(). Currently key_pressed() is a dummy 3851 function, returning 1 and thus enabling modem 3852 initialization. 3853 3854 If there are no modem init strings in the 3855 environment, U-Boot proceed to autoboot; the 3856 previous output (banner, info printfs) will be 3857 suppressed, though. 3858 3859 See also: doc/README.Modem 3860 3861Board initialization settings: 3862------------------------------ 3863 3864During Initialization u-boot calls a number of board specific functions 3865to allow the preparation of board specific prerequisites, e.g. pin setup 3866before drivers are initialized. To enable these callbacks the 3867following configuration macros have to be defined. Currently this is 3868architecture specific, so please check arch/your_architecture/lib/board.c 3869typically in board_init_f() and board_init_r(). 3870 3871- CONFIG_BOARD_EARLY_INIT_F: Call board_early_init_f() 3872- CONFIG_BOARD_EARLY_INIT_R: Call board_early_init_r() 3873- CONFIG_BOARD_LATE_INIT: Call board_late_init() 3874- CONFIG_BOARD_POSTCLK_INIT: Call board_postclk_init() 3875 3876Configuration Settings: 3877----------------------- 3878 3879- CONFIG_SYS_SUPPORT_64BIT_DATA: Defined automatically if compiled as 64-bit. 3880 Optionally it can be defined to support 64-bit memory commands. 3881 3882- CONFIG_SYS_LONGHELP: Defined when you want long help messages included; 3883 undefine this when you're short of memory. 3884 3885- CONFIG_SYS_HELP_CMD_WIDTH: Defined when you want to override the default 3886 width of the commands listed in the 'help' command output. 3887 3888- CONFIG_SYS_PROMPT: This is what U-Boot prints on the console to 3889 prompt for user input. 3890 3891- CONFIG_SYS_CBSIZE: Buffer size for input from the Console 3892 3893- CONFIG_SYS_PBSIZE: Buffer size for Console output 3894 3895- CONFIG_SYS_MAXARGS: max. Number of arguments accepted for monitor commands 3896 3897- CONFIG_SYS_BARGSIZE: Buffer size for Boot Arguments which are passed to 3898 the application (usually a Linux kernel) when it is 3899 booted 3900 3901- CONFIG_SYS_BAUDRATE_TABLE: 3902 List of legal baudrate settings for this board. 3903 3904- CONFIG_SYS_CONSOLE_INFO_QUIET 3905 Suppress display of console information at boot. 3906 3907- CONFIG_SYS_CONSOLE_IS_IN_ENV 3908 If the board specific function 3909 extern int overwrite_console (void); 3910 returns 1, the stdin, stderr and stdout are switched to the 3911 serial port, else the settings in the environment are used. 3912 3913- CONFIG_SYS_CONSOLE_OVERWRITE_ROUTINE 3914 Enable the call to overwrite_console(). 3915 3916- CONFIG_SYS_CONSOLE_ENV_OVERWRITE 3917 Enable overwrite of previous console environment settings. 3918 3919- CONFIG_SYS_MEMTEST_START, CONFIG_SYS_MEMTEST_END: 3920 Begin and End addresses of the area used by the 3921 simple memory test. 3922 3923- CONFIG_SYS_ALT_MEMTEST: 3924 Enable an alternate, more extensive memory test. 3925 3926- CONFIG_SYS_MEMTEST_SCRATCH: 3927 Scratch address used by the alternate memory test 3928 You only need to set this if address zero isn't writeable 3929 3930- CONFIG_SYS_MEM_TOP_HIDE (PPC only): 3931 If CONFIG_SYS_MEM_TOP_HIDE is defined in the board config header, 3932 this specified memory area will get subtracted from the top 3933 (end) of RAM and won't get "touched" at all by U-Boot. By 3934 fixing up gd->ram_size the Linux kernel should gets passed 3935 the now "corrected" memory size and won't touch it either. 3936 This should work for arch/ppc and arch/powerpc. Only Linux 3937 board ports in arch/powerpc with bootwrapper support that 3938 recalculate the memory size from the SDRAM controller setup 3939 will have to get fixed in Linux additionally. 3940 3941 This option can be used as a workaround for the 440EPx/GRx 3942 CHIP 11 errata where the last 256 bytes in SDRAM shouldn't 3943 be touched. 3944 3945 WARNING: Please make sure that this value is a multiple of 3946 the Linux page size (normally 4k). If this is not the case, 3947 then the end address of the Linux memory will be located at a 3948 non page size aligned address and this could cause major 3949 problems. 3950 3951- CONFIG_SYS_LOADS_BAUD_CHANGE: 3952 Enable temporary baudrate change while serial download 3953 3954- CONFIG_SYS_SDRAM_BASE: 3955 Physical start address of SDRAM. _Must_ be 0 here. 3956 3957- CONFIG_SYS_MBIO_BASE: 3958 Physical start address of Motherboard I/O (if using a 3959 Cogent motherboard) 3960 3961- CONFIG_SYS_FLASH_BASE: 3962 Physical start address of Flash memory. 3963 3964- CONFIG_SYS_MONITOR_BASE: 3965 Physical start address of boot monitor code (set by 3966 make config files to be same as the text base address 3967 (CONFIG_SYS_TEXT_BASE) used when linking) - same as 3968 CONFIG_SYS_FLASH_BASE when booting from flash. 3969 3970- CONFIG_SYS_MONITOR_LEN: 3971 Size of memory reserved for monitor code, used to 3972 determine _at_compile_time_ (!) if the environment is 3973 embedded within the U-Boot image, or in a separate 3974 flash sector. 3975 3976- CONFIG_SYS_MALLOC_LEN: 3977 Size of DRAM reserved for malloc() use. 3978 3979- CONFIG_SYS_MALLOC_F_LEN 3980 Size of the malloc() pool for use before relocation. If 3981 this is defined, then a very simple malloc() implementation 3982 will become available before relocation. The address is just 3983 below the global data, and the stack is moved down to make 3984 space. 3985 3986 This feature allocates regions with increasing addresses 3987 within the region. calloc() is supported, but realloc() 3988 is not available. free() is supported but does nothing. 3989 The memory will be freed (or in fact just forgotten) when 3990 U-Boot relocates itself. 3991 3992 Pre-relocation malloc() is only supported on ARM and sandbox 3993 at present but is fairly easy to enable for other archs. 3994 3995- CONFIG_SYS_MALLOC_SIMPLE 3996 Provides a simple and small malloc() and calloc() for those 3997 boards which do not use the full malloc in SPL (which is 3998 enabled with CONFIG_SYS_SPL_MALLOC_START). 3999 4000- CONFIG_SYS_NONCACHED_MEMORY: 4001 Size of non-cached memory area. This area of memory will be 4002 typically located right below the malloc() area and mapped 4003 uncached in the MMU. This is useful for drivers that would 4004 otherwise require a lot of explicit cache maintenance. For 4005 some drivers it's also impossible to properly maintain the 4006 cache. For example if the regions that need to be flushed 4007 are not a multiple of the cache-line size, *and* padding 4008 cannot be allocated between the regions to align them (i.e. 4009 if the HW requires a contiguous array of regions, and the 4010 size of each region is not cache-aligned), then a flush of 4011 one region may result in overwriting data that hardware has 4012 written to another region in the same cache-line. This can 4013 happen for example in network drivers where descriptors for 4014 buffers are typically smaller than the CPU cache-line (e.g. 4015 16 bytes vs. 32 or 64 bytes). 4016 4017 Non-cached memory is only supported on 32-bit ARM at present. 4018 4019- CONFIG_SYS_BOOTM_LEN: 4020 Normally compressed uImages are limited to an 4021 uncompressed size of 8 MBytes. If this is not enough, 4022 you can define CONFIG_SYS_BOOTM_LEN in your board config file 4023 to adjust this setting to your needs. 4024 4025- CONFIG_SYS_BOOTMAPSZ: 4026 Maximum size of memory mapped by the startup code of 4027 the Linux kernel; all data that must be processed by 4028 the Linux kernel (bd_info, boot arguments, FDT blob if 4029 used) must be put below this limit, unless "bootm_low" 4030 environment variable is defined and non-zero. In such case 4031 all data for the Linux kernel must be between "bootm_low" 4032 and "bootm_low" + CONFIG_SYS_BOOTMAPSZ. The environment 4033 variable "bootm_mapsize" will override the value of 4034 CONFIG_SYS_BOOTMAPSZ. If CONFIG_SYS_BOOTMAPSZ is undefined, 4035 then the value in "bootm_size" will be used instead. 4036 4037- CONFIG_SYS_BOOT_RAMDISK_HIGH: 4038 Enable initrd_high functionality. If defined then the 4039 initrd_high feature is enabled and the bootm ramdisk subcommand 4040 is enabled. 4041 4042- CONFIG_SYS_BOOT_GET_CMDLINE: 4043 Enables allocating and saving kernel cmdline in space between 4044 "bootm_low" and "bootm_low" + BOOTMAPSZ. 4045 4046- CONFIG_SYS_BOOT_GET_KBD: 4047 Enables allocating and saving a kernel copy of the bd_info in 4048 space between "bootm_low" and "bootm_low" + BOOTMAPSZ. 4049 4050- CONFIG_SYS_MAX_FLASH_BANKS: 4051 Max number of Flash memory banks 4052 4053- CONFIG_SYS_MAX_FLASH_SECT: 4054 Max number of sectors on a Flash chip 4055 4056- CONFIG_SYS_FLASH_ERASE_TOUT: 4057 Timeout for Flash erase operations (in ms) 4058 4059- CONFIG_SYS_FLASH_WRITE_TOUT: 4060 Timeout for Flash write operations (in ms) 4061 4062- CONFIG_SYS_FLASH_LOCK_TOUT 4063 Timeout for Flash set sector lock bit operation (in ms) 4064 4065- CONFIG_SYS_FLASH_UNLOCK_TOUT 4066 Timeout for Flash clear lock bits operation (in ms) 4067 4068- CONFIG_SYS_FLASH_PROTECTION 4069 If defined, hardware flash sectors protection is used 4070 instead of U-Boot software protection. 4071 4072- CONFIG_SYS_DIRECT_FLASH_TFTP: 4073 4074 Enable TFTP transfers directly to flash memory; 4075 without this option such a download has to be 4076 performed in two steps: (1) download to RAM, and (2) 4077 copy from RAM to flash. 4078 4079 The two-step approach is usually more reliable, since 4080 you can check if the download worked before you erase 4081 the flash, but in some situations (when system RAM is 4082 too limited to allow for a temporary copy of the 4083 downloaded image) this option may be very useful. 4084 4085- CONFIG_SYS_FLASH_CFI: 4086 Define if the flash driver uses extra elements in the 4087 common flash structure for storing flash geometry. 4088 4089- CONFIG_FLASH_CFI_DRIVER 4090 This option also enables the building of the cfi_flash driver 4091 in the drivers directory 4092 4093- CONFIG_FLASH_CFI_MTD 4094 This option enables the building of the cfi_mtd driver 4095 in the drivers directory. The driver exports CFI flash 4096 to the MTD layer. 4097 4098- CONFIG_SYS_FLASH_USE_BUFFER_WRITE 4099 Use buffered writes to flash. 4100 4101- CONFIG_FLASH_SPANSION_S29WS_N 4102 s29ws-n MirrorBit flash has non-standard addresses for buffered 4103 write commands. 4104 4105- CONFIG_SYS_FLASH_QUIET_TEST 4106 If this option is defined, the common CFI flash doesn't 4107 print it's warning upon not recognized FLASH banks. This 4108 is useful, if some of the configured banks are only 4109 optionally available. 4110 4111- CONFIG_FLASH_SHOW_PROGRESS 4112 If defined (must be an integer), print out countdown 4113 digits and dots. Recommended value: 45 (9..1) for 80 4114 column displays, 15 (3..1) for 40 column displays. 4115 4116- CONFIG_FLASH_VERIFY 4117 If defined, the content of the flash (destination) is compared 4118 against the source after the write operation. An error message 4119 will be printed when the contents are not identical. 4120 Please note that this option is useless in nearly all cases, 4121 since such flash programming errors usually are detected earlier 4122 while unprotecting/erasing/programming. Please only enable 4123 this option if you really know what you are doing. 4124 4125- CONFIG_SYS_RX_ETH_BUFFER: 4126 Defines the number of Ethernet receive buffers. On some 4127 Ethernet controllers it is recommended to set this value 4128 to 8 or even higher (EEPRO100 or 405 EMAC), since all 4129 buffers can be full shortly after enabling the interface 4130 on high Ethernet traffic. 4131 Defaults to 4 if not defined. 4132 4133- CONFIG_ENV_MAX_ENTRIES 4134 4135 Maximum number of entries in the hash table that is used 4136 internally to store the environment settings. The default 4137 setting is supposed to be generous and should work in most 4138 cases. This setting can be used to tune behaviour; see 4139 lib/hashtable.c for details. 4140 4141- CONFIG_ENV_FLAGS_LIST_DEFAULT 4142- CONFIG_ENV_FLAGS_LIST_STATIC 4143 Enable validation of the values given to environment variables when 4144 calling env set. Variables can be restricted to only decimal, 4145 hexadecimal, or boolean. If CONFIG_CMD_NET is also defined, 4146 the variables can also be restricted to IP address or MAC address. 4147 4148 The format of the list is: 4149 type_attribute = [s|d|x|b|i|m] 4150 access_attribute = [a|r|o|c] 4151 attributes = type_attribute[access_attribute] 4152 entry = variable_name[:attributes] 4153 list = entry[,list] 4154 4155 The type attributes are: 4156 s - String (default) 4157 d - Decimal 4158 x - Hexadecimal 4159 b - Boolean ([1yYtT|0nNfF]) 4160 i - IP address 4161 m - MAC address 4162 4163 The access attributes are: 4164 a - Any (default) 4165 r - Read-only 4166 o - Write-once 4167 c - Change-default 4168 4169 - CONFIG_ENV_FLAGS_LIST_DEFAULT 4170 Define this to a list (string) to define the ".flags" 4171 environment variable in the default or embedded environment. 4172 4173 - CONFIG_ENV_FLAGS_LIST_STATIC 4174 Define this to a list (string) to define validation that 4175 should be done if an entry is not found in the ".flags" 4176 environment variable. To override a setting in the static 4177 list, simply add an entry for the same variable name to the 4178 ".flags" variable. 4179 4180- CONFIG_ENV_ACCESS_IGNORE_FORCE 4181 If defined, don't allow the -f switch to env set override variable 4182 access flags. 4183 4184- CONFIG_SYS_GENERIC_BOARD 4185 This selects the architecture-generic board system instead of the 4186 architecture-specific board files. It is intended to move boards 4187 to this new framework over time. Defining this will disable the 4188 arch/foo/lib/board.c file and use common/board_f.c and 4189 common/board_r.c instead. To use this option your architecture 4190 must support it (i.e. must select HAVE_GENERIC_BOARD in arch/Kconfig). 4191 If you find problems enabling this option on your board please report 4192 the problem and send patches! 4193 4194- CONFIG_OMAP_PLATFORM_RESET_TIME_MAX_USEC (OMAP only) 4195 This is set by OMAP boards for the max time that reset should 4196 be asserted. See doc/README.omap-reset-time for details on how 4197 the value can be calculated on a given board. 4198 4199- CONFIG_USE_STDINT 4200 If stdint.h is available with your toolchain you can define this 4201 option to enable it. You can provide option 'USE_STDINT=1' when 4202 building U-Boot to enable this. 4203 4204The following definitions that deal with the placement and management 4205of environment data (variable area); in general, we support the 4206following configurations: 4207 4208- CONFIG_BUILD_ENVCRC: 4209 4210 Builds up envcrc with the target environment so that external utils 4211 may easily extract it and embed it in final U-Boot images. 4212 4213- CONFIG_ENV_IS_IN_FLASH: 4214 4215 Define this if the environment is in flash memory. 4216 4217 a) The environment occupies one whole flash sector, which is 4218 "embedded" in the text segment with the U-Boot code. This 4219 happens usually with "bottom boot sector" or "top boot 4220 sector" type flash chips, which have several smaller 4221 sectors at the start or the end. For instance, such a 4222 layout can have sector sizes of 8, 2x4, 16, Nx32 kB. In 4223 such a case you would place the environment in one of the 4224 4 kB sectors - with U-Boot code before and after it. With 4225 "top boot sector" type flash chips, you would put the 4226 environment in one of the last sectors, leaving a gap 4227 between U-Boot and the environment. 4228 4229 - CONFIG_ENV_OFFSET: 4230 4231 Offset of environment data (variable area) to the 4232 beginning of flash memory; for instance, with bottom boot 4233 type flash chips the second sector can be used: the offset 4234 for this sector is given here. 4235 4236 CONFIG_ENV_OFFSET is used relative to CONFIG_SYS_FLASH_BASE. 4237 4238 - CONFIG_ENV_ADDR: 4239 4240 This is just another way to specify the start address of 4241 the flash sector containing the environment (instead of 4242 CONFIG_ENV_OFFSET). 4243 4244 - CONFIG_ENV_SECT_SIZE: 4245 4246 Size of the sector containing the environment. 4247 4248 4249 b) Sometimes flash chips have few, equal sized, BIG sectors. 4250 In such a case you don't want to spend a whole sector for 4251 the environment. 4252 4253 - CONFIG_ENV_SIZE: 4254 4255 If you use this in combination with CONFIG_ENV_IS_IN_FLASH 4256 and CONFIG_ENV_SECT_SIZE, you can specify to use only a part 4257 of this flash sector for the environment. This saves 4258 memory for the RAM copy of the environment. 4259 4260 It may also save flash memory if you decide to use this 4261 when your environment is "embedded" within U-Boot code, 4262 since then the remainder of the flash sector could be used 4263 for U-Boot code. It should be pointed out that this is 4264 STRONGLY DISCOURAGED from a robustness point of view: 4265 updating the environment in flash makes it always 4266 necessary to erase the WHOLE sector. If something goes 4267 wrong before the contents has been restored from a copy in 4268 RAM, your target system will be dead. 4269 4270 - CONFIG_ENV_ADDR_REDUND 4271 CONFIG_ENV_SIZE_REDUND 4272 4273 These settings describe a second storage area used to hold 4274 a redundant copy of the environment data, so that there is 4275 a valid backup copy in case there is a power failure during 4276 a "saveenv" operation. 4277 4278BE CAREFUL! Any changes to the flash layout, and some changes to the 4279source code will make it necessary to adapt <board>/u-boot.lds* 4280accordingly! 4281 4282 4283- CONFIG_ENV_IS_IN_NVRAM: 4284 4285 Define this if you have some non-volatile memory device 4286 (NVRAM, battery buffered SRAM) which you want to use for the 4287 environment. 4288 4289 - CONFIG_ENV_ADDR: 4290 - CONFIG_ENV_SIZE: 4291 4292 These two #defines are used to determine the memory area you 4293 want to use for environment. It is assumed that this memory 4294 can just be read and written to, without any special 4295 provision. 4296 4297BE CAREFUL! The first access to the environment happens quite early 4298in U-Boot initialization (when we try to get the setting of for the 4299console baudrate). You *MUST* have mapped your NVRAM area then, or 4300U-Boot will hang. 4301 4302Please note that even with NVRAM we still use a copy of the 4303environment in RAM: we could work on NVRAM directly, but we want to 4304keep settings there always unmodified except somebody uses "saveenv" 4305to save the current settings. 4306 4307 4308- CONFIG_ENV_IS_IN_EEPROM: 4309 4310 Use this if you have an EEPROM or similar serial access 4311 device and a driver for it. 4312 4313 - CONFIG_ENV_OFFSET: 4314 - CONFIG_ENV_SIZE: 4315 4316 These two #defines specify the offset and size of the 4317 environment area within the total memory of your EEPROM. 4318 4319 - CONFIG_SYS_I2C_EEPROM_ADDR: 4320 If defined, specified the chip address of the EEPROM device. 4321 The default address is zero. 4322 4323 - CONFIG_SYS_I2C_EEPROM_BUS: 4324 If defined, specified the i2c bus of the EEPROM device. 4325 4326 - CONFIG_SYS_EEPROM_PAGE_WRITE_BITS: 4327 If defined, the number of bits used to address bytes in a 4328 single page in the EEPROM device. A 64 byte page, for example 4329 would require six bits. 4330 4331 - CONFIG_SYS_EEPROM_PAGE_WRITE_DELAY_MS: 4332 If defined, the number of milliseconds to delay between 4333 page writes. The default is zero milliseconds. 4334 4335 - CONFIG_SYS_I2C_EEPROM_ADDR_LEN: 4336 The length in bytes of the EEPROM memory array address. Note 4337 that this is NOT the chip address length! 4338 4339 - CONFIG_SYS_I2C_EEPROM_ADDR_OVERFLOW: 4340 EEPROM chips that implement "address overflow" are ones 4341 like Catalyst 24WC04/08/16 which has 9/10/11 bits of 4342 address and the extra bits end up in the "chip address" bit 4343 slots. This makes a 24WC08 (1Kbyte) chip look like four 256 4344 byte chips. 4345 4346 Note that we consider the length of the address field to 4347 still be one byte because the extra address bits are hidden 4348 in the chip address. 4349 4350 - CONFIG_SYS_EEPROM_SIZE: 4351 The size in bytes of the EEPROM device. 4352 4353 - CONFIG_ENV_EEPROM_IS_ON_I2C 4354 define this, if you have I2C and SPI activated, and your 4355 EEPROM, which holds the environment, is on the I2C bus. 4356 4357 - CONFIG_I2C_ENV_EEPROM_BUS 4358 if you have an Environment on an EEPROM reached over 4359 I2C muxes, you can define here, how to reach this 4360 EEPROM. For example: 4361 4362 #define CONFIG_I2C_ENV_EEPROM_BUS 1 4363 4364 EEPROM which holds the environment, is reached over 4365 a pca9547 i2c mux with address 0x70, channel 3. 4366 4367- CONFIG_ENV_IS_IN_DATAFLASH: 4368 4369 Define this if you have a DataFlash memory device which you 4370 want to use for the environment. 4371 4372 - CONFIG_ENV_OFFSET: 4373 - CONFIG_ENV_ADDR: 4374 - CONFIG_ENV_SIZE: 4375 4376 These three #defines specify the offset and size of the 4377 environment area within the total memory of your DataFlash placed 4378 at the specified address. 4379 4380- CONFIG_ENV_IS_IN_SPI_FLASH: 4381 4382 Define this if you have a SPI Flash memory device which you 4383 want to use for the environment. 4384 4385 - CONFIG_ENV_OFFSET: 4386 - CONFIG_ENV_SIZE: 4387 4388 These two #defines specify the offset and size of the 4389 environment area within the SPI Flash. CONFIG_ENV_OFFSET must be 4390 aligned to an erase sector boundary. 4391 4392 - CONFIG_ENV_SECT_SIZE: 4393 4394 Define the SPI flash's sector size. 4395 4396 - CONFIG_ENV_OFFSET_REDUND (optional): 4397 4398 This setting describes a second storage area of CONFIG_ENV_SIZE 4399 size used to hold a redundant copy of the environment data, so 4400 that there is a valid backup copy in case there is a power failure 4401 during a "saveenv" operation. CONFIG_ENV_OFFSET_RENDUND must be 4402 aligned to an erase sector boundary. 4403 4404 - CONFIG_ENV_SPI_BUS (optional): 4405 - CONFIG_ENV_SPI_CS (optional): 4406 4407 Define the SPI bus and chip select. If not defined they will be 0. 4408 4409 - CONFIG_ENV_SPI_MAX_HZ (optional): 4410 4411 Define the SPI max work clock. If not defined then use 1MHz. 4412 4413 - CONFIG_ENV_SPI_MODE (optional): 4414 4415 Define the SPI work mode. If not defined then use SPI_MODE_3. 4416 4417- CONFIG_ENV_IS_IN_REMOTE: 4418 4419 Define this if you have a remote memory space which you 4420 want to use for the local device's environment. 4421 4422 - CONFIG_ENV_ADDR: 4423 - CONFIG_ENV_SIZE: 4424 4425 These two #defines specify the address and size of the 4426 environment area within the remote memory space. The 4427 local device can get the environment from remote memory 4428 space by SRIO or PCIE links. 4429 4430BE CAREFUL! For some special cases, the local device can not use 4431"saveenv" command. For example, the local device will get the 4432environment stored in a remote NOR flash by SRIO or PCIE link, 4433but it can not erase, write this NOR flash by SRIO or PCIE interface. 4434 4435- CONFIG_ENV_IS_IN_NAND: 4436 4437 Define this if you have a NAND device which you want to use 4438 for the environment. 4439 4440 - CONFIG_ENV_OFFSET: 4441 - CONFIG_ENV_SIZE: 4442 4443 These two #defines specify the offset and size of the environment 4444 area within the first NAND device. CONFIG_ENV_OFFSET must be 4445 aligned to an erase block boundary. 4446 4447 - CONFIG_ENV_OFFSET_REDUND (optional): 4448 4449 This setting describes a second storage area of CONFIG_ENV_SIZE 4450 size used to hold a redundant copy of the environment data, so 4451 that there is a valid backup copy in case there is a power failure 4452 during a "saveenv" operation. CONFIG_ENV_OFFSET_RENDUND must be 4453 aligned to an erase block boundary. 4454 4455 - CONFIG_ENV_RANGE (optional): 4456 4457 Specifies the length of the region in which the environment 4458 can be written. This should be a multiple of the NAND device's 4459 block size. Specifying a range with more erase blocks than 4460 are needed to hold CONFIG_ENV_SIZE allows bad blocks within 4461 the range to be avoided. 4462 4463 - CONFIG_ENV_OFFSET_OOB (optional): 4464 4465 Enables support for dynamically retrieving the offset of the 4466 environment from block zero's out-of-band data. The 4467 "nand env.oob" command can be used to record this offset. 4468 Currently, CONFIG_ENV_OFFSET_REDUND is not supported when 4469 using CONFIG_ENV_OFFSET_OOB. 4470 4471- CONFIG_NAND_ENV_DST 4472 4473 Defines address in RAM to which the nand_spl code should copy the 4474 environment. If redundant environment is used, it will be copied to 4475 CONFIG_NAND_ENV_DST + CONFIG_ENV_SIZE. 4476 4477- CONFIG_ENV_IS_IN_UBI: 4478 4479 Define this if you have an UBI volume that you want to use for the 4480 environment. This has the benefit of wear-leveling the environment 4481 accesses, which is important on NAND. 4482 4483 - CONFIG_ENV_UBI_PART: 4484 4485 Define this to a string that is the mtd partition containing the UBI. 4486 4487 - CONFIG_ENV_UBI_VOLUME: 4488 4489 Define this to the name of the volume that you want to store the 4490 environment in. 4491 4492 - CONFIG_ENV_UBI_VOLUME_REDUND: 4493 4494 Define this to the name of another volume to store a second copy of 4495 the environment in. This will enable redundant environments in UBI. 4496 It is assumed that both volumes are in the same MTD partition. 4497 4498 - CONFIG_UBI_SILENCE_MSG 4499 - CONFIG_UBIFS_SILENCE_MSG 4500 4501 You will probably want to define these to avoid a really noisy system 4502 when storing the env in UBI. 4503 4504- CONFIG_ENV_IS_IN_FAT: 4505 Define this if you want to use the FAT file system for the environment. 4506 4507 - FAT_ENV_INTERFACE: 4508 4509 Define this to a string that is the name of the block device. 4510 4511 - FAT_ENV_DEV_AND_PART: 4512 4513 Define this to a string to specify the partition of the device. It can 4514 be as following: 4515 4516 "D:P", "D:0", "D", "D:" or "D:auto" (D, P are integers. And P >= 1) 4517 - "D:P": device D partition P. Error occurs if device D has no 4518 partition table. 4519 - "D:0": device D. 4520 - "D" or "D:": device D partition 1 if device D has partition 4521 table, or the whole device D if has no partition 4522 table. 4523 - "D:auto": first partition in device D with bootable flag set. 4524 If none, first valid partition in device D. If no 4525 partition table then means device D. 4526 4527 - FAT_ENV_FILE: 4528 4529 It's a string of the FAT file name. This file use to store the 4530 environment. 4531 4532 - CONFIG_FAT_WRITE: 4533 This should be defined. Otherwise it cannot save the environment file. 4534 4535- CONFIG_ENV_IS_IN_MMC: 4536 4537 Define this if you have an MMC device which you want to use for the 4538 environment. 4539 4540 - CONFIG_SYS_MMC_ENV_DEV: 4541 4542 Specifies which MMC device the environment is stored in. 4543 4544 - CONFIG_SYS_MMC_ENV_PART (optional): 4545 4546 Specifies which MMC partition the environment is stored in. If not 4547 set, defaults to partition 0, the user area. Common values might be 4548 1 (first MMC boot partition), 2 (second MMC boot partition). 4549 4550 - CONFIG_ENV_OFFSET: 4551 - CONFIG_ENV_SIZE: 4552 4553 These two #defines specify the offset and size of the environment 4554 area within the specified MMC device. 4555 4556 If offset is positive (the usual case), it is treated as relative to 4557 the start of the MMC partition. If offset is negative, it is treated 4558 as relative to the end of the MMC partition. This can be useful if 4559 your board may be fitted with different MMC devices, which have 4560 different sizes for the MMC partitions, and you always want the 4561 environment placed at the very end of the partition, to leave the 4562 maximum possible space before it, to store other data. 4563 4564 These two values are in units of bytes, but must be aligned to an 4565 MMC sector boundary. 4566 4567 - CONFIG_ENV_OFFSET_REDUND (optional): 4568 4569 Specifies a second storage area, of CONFIG_ENV_SIZE size, used to 4570 hold a redundant copy of the environment data. This provides a 4571 valid backup copy in case the other copy is corrupted, e.g. due 4572 to a power failure during a "saveenv" operation. 4573 4574 This value may also be positive or negative; this is handled in the 4575 same way as CONFIG_ENV_OFFSET. 4576 4577 This value is also in units of bytes, but must also be aligned to 4578 an MMC sector boundary. 4579 4580 - CONFIG_ENV_SIZE_REDUND (optional): 4581 4582 This value need not be set, even when CONFIG_ENV_OFFSET_REDUND is 4583 set. If this value is set, it must be set to the same value as 4584 CONFIG_ENV_SIZE. 4585 4586- CONFIG_SYS_SPI_INIT_OFFSET 4587 4588 Defines offset to the initial SPI buffer area in DPRAM. The 4589 area is used at an early stage (ROM part) if the environment 4590 is configured to reside in the SPI EEPROM: We need a 520 byte 4591 scratch DPRAM area. It is used between the two initialization 4592 calls (spi_init_f() and spi_init_r()). A value of 0xB00 seems 4593 to be a good choice since it makes it far enough from the 4594 start of the data area as well as from the stack pointer. 4595 4596Please note that the environment is read-only until the monitor 4597has been relocated to RAM and a RAM copy of the environment has been 4598created; also, when using EEPROM you will have to use getenv_f() 4599until then to read environment variables. 4600 4601The environment is protected by a CRC32 checksum. Before the monitor 4602is relocated into RAM, as a result of a bad CRC you will be working 4603with the compiled-in default environment - *silently*!!! [This is 4604necessary, because the first environment variable we need is the 4605"baudrate" setting for the console - if we have a bad CRC, we don't 4606have any device yet where we could complain.] 4607 4608Note: once the monitor has been relocated, then it will complain if 4609the default environment is used; a new CRC is computed as soon as you 4610use the "saveenv" command to store a valid environment. 4611 4612- CONFIG_SYS_FAULT_ECHO_LINK_DOWN: 4613 Echo the inverted Ethernet link state to the fault LED. 4614 4615 Note: If this option is active, then CONFIG_SYS_FAULT_MII_ADDR 4616 also needs to be defined. 4617 4618- CONFIG_SYS_FAULT_MII_ADDR: 4619 MII address of the PHY to check for the Ethernet link state. 4620 4621- CONFIG_NS16550_MIN_FUNCTIONS: 4622 Define this if you desire to only have use of the NS16550_init 4623 and NS16550_putc functions for the serial driver located at 4624 drivers/serial/ns16550.c. This option is useful for saving 4625 space for already greatly restricted images, including but not 4626 limited to NAND_SPL configurations. 4627 4628- CONFIG_DISPLAY_BOARDINFO 4629 Display information about the board that U-Boot is running on 4630 when U-Boot starts up. The board function checkboard() is called 4631 to do this. 4632 4633- CONFIG_DISPLAY_BOARDINFO_LATE 4634 Similar to the previous option, but display this information 4635 later, once stdio is running and output goes to the LCD, if 4636 present. 4637 4638- CONFIG_BOARD_SIZE_LIMIT: 4639 Maximum size of the U-Boot image. When defined, the 4640 build system checks that the actual size does not 4641 exceed it. 4642 4643Low Level (hardware related) configuration options: 4644--------------------------------------------------- 4645 4646- CONFIG_SYS_CACHELINE_SIZE: 4647 Cache Line Size of the CPU. 4648 4649- CONFIG_SYS_DEFAULT_IMMR: 4650 Default address of the IMMR after system reset. 4651 4652 Needed on some 8260 systems (MPC8260ADS, PQ2FADS-ZU, 4653 and RPXsuper) to be able to adjust the position of 4654 the IMMR register after a reset. 4655 4656- CONFIG_SYS_CCSRBAR_DEFAULT: 4657 Default (power-on reset) physical address of CCSR on Freescale 4658 PowerPC SOCs. 4659 4660- CONFIG_SYS_CCSRBAR: 4661 Virtual address of CCSR. On a 32-bit build, this is typically 4662 the same value as CONFIG_SYS_CCSRBAR_DEFAULT. 4663 4664 CONFIG_SYS_DEFAULT_IMMR must also be set to this value, 4665 for cross-platform code that uses that macro instead. 4666 4667- CONFIG_SYS_CCSRBAR_PHYS: 4668 Physical address of CCSR. CCSR can be relocated to a new 4669 physical address, if desired. In this case, this macro should 4670 be set to that address. Otherwise, it should be set to the 4671 same value as CONFIG_SYS_CCSRBAR_DEFAULT. For example, CCSR 4672 is typically relocated on 36-bit builds. It is recommended 4673 that this macro be defined via the _HIGH and _LOW macros: 4674 4675 #define CONFIG_SYS_CCSRBAR_PHYS ((CONFIG_SYS_CCSRBAR_PHYS_HIGH 4676 * 1ull) << 32 | CONFIG_SYS_CCSRBAR_PHYS_LOW) 4677 4678- CONFIG_SYS_CCSRBAR_PHYS_HIGH: 4679 Bits 33-36 of CONFIG_SYS_CCSRBAR_PHYS. This value is typically 4680 either 0 (32-bit build) or 0xF (36-bit build). This macro is 4681 used in assembly code, so it must not contain typecasts or 4682 integer size suffixes (e.g. "ULL"). 4683 4684- CONFIG_SYS_CCSRBAR_PHYS_LOW: 4685 Lower 32-bits of CONFIG_SYS_CCSRBAR_PHYS. This macro is 4686 used in assembly code, so it must not contain typecasts or 4687 integer size suffixes (e.g. "ULL"). 4688 4689- CONFIG_SYS_CCSR_DO_NOT_RELOCATE: 4690 If this macro is defined, then CONFIG_SYS_CCSRBAR_PHYS will be 4691 forced to a value that ensures that CCSR is not relocated. 4692 4693- Floppy Disk Support: 4694 CONFIG_SYS_FDC_DRIVE_NUMBER 4695 4696 the default drive number (default value 0) 4697 4698 CONFIG_SYS_ISA_IO_STRIDE 4699 4700 defines the spacing between FDC chipset registers 4701 (default value 1) 4702 4703 CONFIG_SYS_ISA_IO_OFFSET 4704 4705 defines the offset of register from address. It 4706 depends on which part of the data bus is connected to 4707 the FDC chipset. (default value 0) 4708 4709 If CONFIG_SYS_ISA_IO_STRIDE CONFIG_SYS_ISA_IO_OFFSET and 4710 CONFIG_SYS_FDC_DRIVE_NUMBER are undefined, they take their 4711 default value. 4712 4713 if CONFIG_SYS_FDC_HW_INIT is defined, then the function 4714 fdc_hw_init() is called at the beginning of the FDC 4715 setup. fdc_hw_init() must be provided by the board 4716 source code. It is used to make hardware-dependent 4717 initializations. 4718 4719- CONFIG_IDE_AHB: 4720 Most IDE controllers were designed to be connected with PCI 4721 interface. Only few of them were designed for AHB interface. 4722 When software is doing ATA command and data transfer to 4723 IDE devices through IDE-AHB controller, some additional 4724 registers accessing to these kind of IDE-AHB controller 4725 is required. 4726 4727- CONFIG_SYS_IMMR: Physical address of the Internal Memory. 4728 DO NOT CHANGE unless you know exactly what you're 4729 doing! (11-4) [MPC8xx/82xx systems only] 4730 4731- CONFIG_SYS_INIT_RAM_ADDR: 4732 4733 Start address of memory area that can be used for 4734 initial data and stack; please note that this must be 4735 writable memory that is working WITHOUT special 4736 initialization, i. e. you CANNOT use normal RAM which 4737 will become available only after programming the 4738 memory controller and running certain initialization 4739 sequences. 4740 4741 U-Boot uses the following memory types: 4742 - MPC8xx and MPC8260: IMMR (internal memory of the CPU) 4743 - MPC824X: data cache 4744 - PPC4xx: data cache 4745 4746- CONFIG_SYS_GBL_DATA_OFFSET: 4747 4748 Offset of the initial data structure in the memory 4749 area defined by CONFIG_SYS_INIT_RAM_ADDR. Usually 4750 CONFIG_SYS_GBL_DATA_OFFSET is chosen such that the initial 4751 data is located at the end of the available space 4752 (sometimes written as (CONFIG_SYS_INIT_RAM_SIZE - 4753 CONFIG_SYS_INIT_DATA_SIZE), and the initial stack is just 4754 below that area (growing from (CONFIG_SYS_INIT_RAM_ADDR + 4755 CONFIG_SYS_GBL_DATA_OFFSET) downward. 4756 4757 Note: 4758 On the MPC824X (or other systems that use the data 4759 cache for initial memory) the address chosen for 4760 CONFIG_SYS_INIT_RAM_ADDR is basically arbitrary - it must 4761 point to an otherwise UNUSED address space between 4762 the top of RAM and the start of the PCI space. 4763 4764- CONFIG_SYS_SIUMCR: SIU Module Configuration (11-6) 4765 4766- CONFIG_SYS_SYPCR: System Protection Control (11-9) 4767 4768- CONFIG_SYS_TBSCR: Time Base Status and Control (11-26) 4769 4770- CONFIG_SYS_PISCR: Periodic Interrupt Status and Control (11-31) 4771 4772- CONFIG_SYS_PLPRCR: PLL, Low-Power, and Reset Control Register (15-30) 4773 4774- CONFIG_SYS_SCCR: System Clock and reset Control Register (15-27) 4775 4776- CONFIG_SYS_OR_TIMING_SDRAM: 4777 SDRAM timing 4778 4779- CONFIG_SYS_MAMR_PTA: 4780 periodic timer for refresh 4781 4782- CONFIG_SYS_DER: Debug Event Register (37-47) 4783 4784- FLASH_BASE0_PRELIM, FLASH_BASE1_PRELIM, CONFIG_SYS_REMAP_OR_AM, 4785 CONFIG_SYS_PRELIM_OR_AM, CONFIG_SYS_OR_TIMING_FLASH, CONFIG_SYS_OR0_REMAP, 4786 CONFIG_SYS_OR0_PRELIM, CONFIG_SYS_BR0_PRELIM, CONFIG_SYS_OR1_REMAP, CONFIG_SYS_OR1_PRELIM, 4787 CONFIG_SYS_BR1_PRELIM: 4788 Memory Controller Definitions: BR0/1 and OR0/1 (FLASH) 4789 4790- SDRAM_BASE2_PRELIM, SDRAM_BASE3_PRELIM, SDRAM_MAX_SIZE, 4791 CONFIG_SYS_OR_TIMING_SDRAM, CONFIG_SYS_OR2_PRELIM, CONFIG_SYS_BR2_PRELIM, 4792 CONFIG_SYS_OR3_PRELIM, CONFIG_SYS_BR3_PRELIM: 4793 Memory Controller Definitions: BR2/3 and OR2/3 (SDRAM) 4794 4795- CONFIG_SYS_MAMR_PTA, CONFIG_SYS_MPTPR_2BK_4K, CONFIG_SYS_MPTPR_1BK_4K, CONFIG_SYS_MPTPR_2BK_8K, 4796 CONFIG_SYS_MPTPR_1BK_8K, CONFIG_SYS_MAMR_8COL, CONFIG_SYS_MAMR_9COL: 4797 Machine Mode Register and Memory Periodic Timer 4798 Prescaler definitions (SDRAM timing) 4799 4800- CONFIG_SYS_I2C_UCODE_PATCH, CONFIG_SYS_I2C_DPMEM_OFFSET [0x1FC0]: 4801 enable I2C microcode relocation patch (MPC8xx); 4802 define relocation offset in DPRAM [DSP2] 4803 4804- CONFIG_SYS_SMC_UCODE_PATCH, CONFIG_SYS_SMC_DPMEM_OFFSET [0x1FC0]: 4805 enable SMC microcode relocation patch (MPC8xx); 4806 define relocation offset in DPRAM [SMC1] 4807 4808- CONFIG_SYS_SPI_UCODE_PATCH, CONFIG_SYS_SPI_DPMEM_OFFSET [0x1FC0]: 4809 enable SPI microcode relocation patch (MPC8xx); 4810 define relocation offset in DPRAM [SCC4] 4811 4812- CONFIG_SYS_USE_OSCCLK: 4813 Use OSCM clock mode on MBX8xx board. Be careful, 4814 wrong setting might damage your board. Read 4815 doc/README.MBX before setting this variable! 4816 4817- CONFIG_SYS_CPM_POST_WORD_ADDR: (MPC8xx, MPC8260 only) 4818 Offset of the bootmode word in DPRAM used by post 4819 (Power On Self Tests). This definition overrides 4820 #define'd default value in commproc.h resp. 4821 cpm_8260.h. 4822 4823- CONFIG_SYS_PCI_SLV_MEM_LOCAL, CONFIG_SYS_PCI_SLV_MEM_BUS, CONFIG_SYS_PICMR0_MASK_ATTRIB, 4824 CONFIG_SYS_PCI_MSTR0_LOCAL, CONFIG_SYS_PCIMSK0_MASK, CONFIG_SYS_PCI_MSTR1_LOCAL, 4825 CONFIG_SYS_PCIMSK1_MASK, CONFIG_SYS_PCI_MSTR_MEM_LOCAL, CONFIG_SYS_PCI_MSTR_MEM_BUS, 4826 CONFIG_SYS_CPU_PCI_MEM_START, CONFIG_SYS_PCI_MSTR_MEM_SIZE, CONFIG_SYS_POCMR0_MASK_ATTRIB, 4827 CONFIG_SYS_PCI_MSTR_MEMIO_LOCAL, CONFIG_SYS_PCI_MSTR_MEMIO_BUS, CPU_PCI_MEMIO_START, 4828 CONFIG_SYS_PCI_MSTR_MEMIO_SIZE, CONFIG_SYS_POCMR1_MASK_ATTRIB, CONFIG_SYS_PCI_MSTR_IO_LOCAL, 4829 CONFIG_SYS_PCI_MSTR_IO_BUS, CONFIG_SYS_CPU_PCI_IO_START, CONFIG_SYS_PCI_MSTR_IO_SIZE, 4830 CONFIG_SYS_POCMR2_MASK_ATTRIB: (MPC826x only) 4831 Overrides the default PCI memory map in arch/powerpc/cpu/mpc8260/pci.c if set. 4832 4833- CONFIG_PCI_DISABLE_PCIE: 4834 Disable PCI-Express on systems where it is supported but not 4835 required. 4836 4837- CONFIG_PCI_ENUM_ONLY 4838 Only scan through and get the devices on the buses. 4839 Don't do any setup work, presumably because someone or 4840 something has already done it, and we don't need to do it 4841 a second time. Useful for platforms that are pre-booted 4842 by coreboot or similar. 4843 4844- CONFIG_PCI_INDIRECT_BRIDGE: 4845 Enable support for indirect PCI bridges. 4846 4847- CONFIG_SYS_SRIO: 4848 Chip has SRIO or not 4849 4850- CONFIG_SRIO1: 4851 Board has SRIO 1 port available 4852 4853- CONFIG_SRIO2: 4854 Board has SRIO 2 port available 4855 4856- CONFIG_SRIO_PCIE_BOOT_MASTER 4857 Board can support master function for Boot from SRIO and PCIE 4858 4859- CONFIG_SYS_SRIOn_MEM_VIRT: 4860 Virtual Address of SRIO port 'n' memory region 4861 4862- CONFIG_SYS_SRIOn_MEM_PHYS: 4863 Physical Address of SRIO port 'n' memory region 4864 4865- CONFIG_SYS_SRIOn_MEM_SIZE: 4866 Size of SRIO port 'n' memory region 4867 4868- CONFIG_SYS_NAND_BUSWIDTH_16BIT 4869 Defined to tell the NAND controller that the NAND chip is using 4870 a 16 bit bus. 4871 Not all NAND drivers use this symbol. 4872 Example of drivers that use it: 4873 - drivers/mtd/nand/ndfc.c 4874 - drivers/mtd/nand/mxc_nand.c 4875 4876- CONFIG_SYS_NDFC_EBC0_CFG 4877 Sets the EBC0_CFG register for the NDFC. If not defined 4878 a default value will be used. 4879 4880- CONFIG_SPD_EEPROM 4881 Get DDR timing information from an I2C EEPROM. Common 4882 with pluggable memory modules such as SODIMMs 4883 4884 SPD_EEPROM_ADDRESS 4885 I2C address of the SPD EEPROM 4886 4887- CONFIG_SYS_SPD_BUS_NUM 4888 If SPD EEPROM is on an I2C bus other than the first 4889 one, specify here. Note that the value must resolve 4890 to something your driver can deal with. 4891 4892- CONFIG_SYS_DDR_RAW_TIMING 4893 Get DDR timing information from other than SPD. Common with 4894 soldered DDR chips onboard without SPD. DDR raw timing 4895 parameters are extracted from datasheet and hard-coded into 4896 header files or board specific files. 4897 4898- CONFIG_FSL_DDR_INTERACTIVE 4899 Enable interactive DDR debugging. See doc/README.fsl-ddr. 4900 4901- CONFIG_FSL_DDR_SYNC_REFRESH 4902 Enable sync of refresh for multiple controllers. 4903 4904- CONFIG_SYS_83XX_DDR_USES_CS0 4905 Only for 83xx systems. If specified, then DDR should 4906 be configured using CS0 and CS1 instead of CS2 and CS3. 4907 4908- CONFIG_ETHER_ON_FEC[12] 4909 Define to enable FEC[12] on a 8xx series processor. 4910 4911- CONFIG_FEC[12]_PHY 4912 Define to the hardcoded PHY address which corresponds 4913 to the given FEC; i. e. 4914 #define CONFIG_FEC1_PHY 4 4915 means that the PHY with address 4 is connected to FEC1 4916 4917 When set to -1, means to probe for first available. 4918 4919- CONFIG_FEC[12]_PHY_NORXERR 4920 The PHY does not have a RXERR line (RMII only). 4921 (so program the FEC to ignore it). 4922 4923- CONFIG_RMII 4924 Enable RMII mode for all FECs. 4925 Note that this is a global option, we can't 4926 have one FEC in standard MII mode and another in RMII mode. 4927 4928- CONFIG_CRC32_VERIFY 4929 Add a verify option to the crc32 command. 4930 The syntax is: 4931 4932 => crc32 -v <address> <count> <crc32> 4933 4934 Where address/count indicate a memory area 4935 and crc32 is the correct crc32 which the 4936 area should have. 4937 4938- CONFIG_LOOPW 4939 Add the "loopw" memory command. This only takes effect if 4940 the memory commands are activated globally (CONFIG_CMD_MEM). 4941 4942- CONFIG_MX_CYCLIC 4943 Add the "mdc" and "mwc" memory commands. These are cyclic 4944 "md/mw" commands. 4945 Examples: 4946 4947 => mdc.b 10 4 500 4948 This command will print 4 bytes (10,11,12,13) each 500 ms. 4949 4950 => mwc.l 100 12345678 10 4951 This command will write 12345678 to address 100 all 10 ms. 4952 4953 This only takes effect if the memory commands are activated 4954 globally (CONFIG_CMD_MEM). 4955 4956- CONFIG_SKIP_LOWLEVEL_INIT 4957 [ARM, NDS32, MIPS only] If this variable is defined, then certain 4958 low level initializations (like setting up the memory 4959 controller) are omitted and/or U-Boot does not 4960 relocate itself into RAM. 4961 4962 Normally this variable MUST NOT be defined. The only 4963 exception is when U-Boot is loaded (to RAM) by some 4964 other boot loader or by a debugger which performs 4965 these initializations itself. 4966 4967- CONFIG_SPL_BUILD 4968 Modifies the behaviour of start.S when compiling a loader 4969 that is executed before the actual U-Boot. E.g. when 4970 compiling a NAND SPL. 4971 4972- CONFIG_TPL_BUILD 4973 Modifies the behaviour of start.S when compiling a loader 4974 that is executed after the SPL and before the actual U-Boot. 4975 It is loaded by the SPL. 4976 4977- CONFIG_SYS_MPC85XX_NO_RESETVEC 4978 Only for 85xx systems. If this variable is specified, the section 4979 .resetvec is not kept and the section .bootpg is placed in the 4980 previous 4k of the .text section. 4981 4982- CONFIG_ARCH_MAP_SYSMEM 4983 Generally U-Boot (and in particular the md command) uses 4984 effective address. It is therefore not necessary to regard 4985 U-Boot address as virtual addresses that need to be translated 4986 to physical addresses. However, sandbox requires this, since 4987 it maintains its own little RAM buffer which contains all 4988 addressable memory. This option causes some memory accesses 4989 to be mapped through map_sysmem() / unmap_sysmem(). 4990 4991- CONFIG_USE_ARCH_MEMCPY 4992 CONFIG_USE_ARCH_MEMSET 4993 If these options are used a optimized version of memcpy/memset will 4994 be used if available. These functions may be faster under some 4995 conditions but may increase the binary size. 4996 4997- CONFIG_X86_RESET_VECTOR 4998 If defined, the x86 reset vector code is included. This is not 4999 needed when U-Boot is running from Coreboot. 5000 5001- CONFIG_SYS_MPUCLK 5002 Defines the MPU clock speed (in MHz). 5003 5004 NOTE : currently only supported on AM335x platforms. 5005 5006- CONFIG_SPL_AM33XX_ENABLE_RTC32K_OSC: 5007 Enables the RTC32K OSC on AM33xx based plattforms 5008 5009- CONFIG_SYS_NAND_NO_SUBPAGE_WRITE 5010 Option to disable subpage write in NAND driver 5011 driver that uses this: 5012 drivers/mtd/nand/davinci_nand.c 5013 5014Freescale QE/FMAN Firmware Support: 5015----------------------------------- 5016 5017The Freescale QUICCEngine (QE) and Frame Manager (FMAN) both support the 5018loading of "firmware", which is encoded in the QE firmware binary format. 5019This firmware often needs to be loaded during U-Boot booting, so macros 5020are used to identify the storage device (NOR flash, SPI, etc) and the address 5021within that device. 5022 5023- CONFIG_SYS_FMAN_FW_ADDR 5024 The address in the storage device where the FMAN microcode is located. The 5025 meaning of this address depends on which CONFIG_SYS_QE_FW_IN_xxx macro 5026 is also specified. 5027 5028- CONFIG_SYS_QE_FW_ADDR 5029 The address in the storage device where the QE microcode is located. The 5030 meaning of this address depends on which CONFIG_SYS_QE_FW_IN_xxx macro 5031 is also specified. 5032 5033- CONFIG_SYS_QE_FMAN_FW_LENGTH 5034 The maximum possible size of the firmware. The firmware binary format 5035 has a field that specifies the actual size of the firmware, but it 5036 might not be possible to read any part of the firmware unless some 5037 local storage is allocated to hold the entire firmware first. 5038 5039- CONFIG_SYS_QE_FMAN_FW_IN_NOR 5040 Specifies that QE/FMAN firmware is located in NOR flash, mapped as 5041 normal addressable memory via the LBC. CONFIG_SYS_FMAN_FW_ADDR is the 5042 virtual address in NOR flash. 5043 5044- CONFIG_SYS_QE_FMAN_FW_IN_NAND 5045 Specifies that QE/FMAN firmware is located in NAND flash. 5046 CONFIG_SYS_FMAN_FW_ADDR is the offset within NAND flash. 5047 5048- CONFIG_SYS_QE_FMAN_FW_IN_MMC 5049 Specifies that QE/FMAN firmware is located on the primary SD/MMC 5050 device. CONFIG_SYS_FMAN_FW_ADDR is the byte offset on that device. 5051 5052- CONFIG_SYS_QE_FMAN_FW_IN_SPIFLASH 5053 Specifies that QE/FMAN firmware is located on the primary SPI 5054 device. CONFIG_SYS_FMAN_FW_ADDR is the byte offset on that device. 5055 5056- CONFIG_SYS_QE_FMAN_FW_IN_REMOTE 5057 Specifies that QE/FMAN firmware is located in the remote (master) 5058 memory space. CONFIG_SYS_FMAN_FW_ADDR is a virtual address which 5059 can be mapped from slave TLB->slave LAW->slave SRIO or PCIE outbound 5060 window->master inbound window->master LAW->the ucode address in 5061 master's memory space. 5062 5063Freescale Layerscape Management Complex Firmware Support: 5064--------------------------------------------------------- 5065The Freescale Layerscape Management Complex (MC) supports the loading of 5066"firmware". 5067This firmware often needs to be loaded during U-Boot booting, so macros 5068are used to identify the storage device (NOR flash, SPI, etc) and the address 5069within that device. 5070 5071- CONFIG_FSL_MC_ENET 5072 Enable the MC driver for Layerscape SoCs. 5073 5074- CONFIG_SYS_LS_MC_FW_ADDR 5075 The address in the storage device where the firmware is located. The 5076 meaning of this address depends on which CONFIG_SYS_LS_MC_FW_IN_xxx macro 5077 is also specified. 5078 5079- CONFIG_SYS_LS_MC_FW_LENGTH 5080 The maximum possible size of the firmware. The firmware binary format 5081 has a field that specifies the actual size of the firmware, but it 5082 might not be possible to read any part of the firmware unless some 5083 local storage is allocated to hold the entire firmware first. 5084 5085- CONFIG_SYS_LS_MC_FW_IN_NOR 5086 Specifies that MC firmware is located in NOR flash, mapped as 5087 normal addressable memory via the LBC. CONFIG_SYS_LS_MC_FW_ADDR is the 5088 virtual address in NOR flash. 5089 5090Building the Software: 5091====================== 5092 5093Building U-Boot has been tested in several native build environments 5094and in many different cross environments. Of course we cannot support 5095all possibly existing versions of cross development tools in all 5096(potentially obsolete) versions. In case of tool chain problems we 5097recommend to use the ELDK (see http://www.denx.de/wiki/DULG/ELDK) 5098which is extensively used to build and test U-Boot. 5099 5100If you are not using a native environment, it is assumed that you 5101have GNU cross compiling tools available in your path. In this case, 5102you must set the environment variable CROSS_COMPILE in your shell. 5103Note that no changes to the Makefile or any other source files are 5104necessary. For example using the ELDK on a 4xx CPU, please enter: 5105 5106 $ CROSS_COMPILE=ppc_4xx- 5107 $ export CROSS_COMPILE 5108 5109Note: If you wish to generate Windows versions of the utilities in 5110 the tools directory you can use the MinGW toolchain 5111 (http://www.mingw.org). Set your HOST tools to the MinGW 5112 toolchain and execute 'make tools'. For example: 5113 5114 $ make HOSTCC=i586-mingw32msvc-gcc HOSTSTRIP=i586-mingw32msvc-strip tools 5115 5116 Binaries such as tools/mkimage.exe will be created which can 5117 be executed on computers running Windows. 5118 5119U-Boot is intended to be simple to build. After installing the 5120sources you must configure U-Boot for one specific board type. This 5121is done by typing: 5122 5123 make NAME_defconfig 5124 5125where "NAME_defconfig" is the name of one of the existing configu- 5126rations; see boards.cfg for supported names. 5127 5128Note: for some board special configuration names may exist; check if 5129 additional information is available from the board vendor; for 5130 instance, the TQM823L systems are available without (standard) 5131 or with LCD support. You can select such additional "features" 5132 when choosing the configuration, i. e. 5133 5134 make TQM823L_defconfig 5135 - will configure for a plain TQM823L, i. e. no LCD support 5136 5137 make TQM823L_LCD_defconfig 5138 - will configure for a TQM823L with U-Boot console on LCD 5139 5140 etc. 5141 5142 5143Finally, type "make all", and you should get some working U-Boot 5144images ready for download to / installation on your system: 5145 5146- "u-boot.bin" is a raw binary image 5147- "u-boot" is an image in ELF binary format 5148- "u-boot.srec" is in Motorola S-Record format 5149 5150By default the build is performed locally and the objects are saved 5151in the source directory. One of the two methods can be used to change 5152this behavior and build U-Boot to some external directory: 5153 51541. Add O= to the make command line invocations: 5155 5156 make O=/tmp/build distclean 5157 make O=/tmp/build NAME_defconfig 5158 make O=/tmp/build all 5159 51602. Set environment variable KBUILD_OUTPUT to point to the desired location: 5161 5162 export KBUILD_OUTPUT=/tmp/build 5163 make distclean 5164 make NAME_defconfig 5165 make all 5166 5167Note that the command line "O=" setting overrides the KBUILD_OUTPUT environment 5168variable. 5169 5170 5171Please be aware that the Makefiles assume you are using GNU make, so 5172for instance on NetBSD you might need to use "gmake" instead of 5173native "make". 5174 5175 5176If the system board that you have is not listed, then you will need 5177to port U-Boot to your hardware platform. To do this, follow these 5178steps: 5179 51801. Add a new configuration option for your board to the toplevel 5181 "boards.cfg" file, using the existing entries as examples. 5182 Follow the instructions there to keep the boards in order. 51832. Create a new directory to hold your board specific code. Add any 5184 files you need. In your board directory, you will need at least 5185 the "Makefile", a "<board>.c", "flash.c" and "u-boot.lds". 51863. Create a new configuration file "include/configs/<board>.h" for 5187 your board 51883. If you're porting U-Boot to a new CPU, then also create a new 5189 directory to hold your CPU specific code. Add any files you need. 51904. Run "make <board>_defconfig" with your new name. 51915. Type "make", and you should get a working "u-boot.srec" file 5192 to be installed on your target system. 51936. Debug and solve any problems that might arise. 5194 [Of course, this last step is much harder than it sounds.] 5195 5196 5197Testing of U-Boot Modifications, Ports to New Hardware, etc.: 5198============================================================== 5199 5200If you have modified U-Boot sources (for instance added a new board 5201or support for new devices, a new CPU, etc.) you are expected to 5202provide feedback to the other developers. The feedback normally takes 5203the form of a "patch", i. e. a context diff against a certain (latest 5204official or latest in the git repository) version of U-Boot sources. 5205 5206But before you submit such a patch, please verify that your modifi- 5207cation did not break existing code. At least make sure that *ALL* of 5208the supported boards compile WITHOUT ANY compiler warnings. To do so, 5209just run the "MAKEALL" script, which will configure and build U-Boot 5210for ALL supported system. Be warned, this will take a while. You can 5211select which (cross) compiler to use by passing a `CROSS_COMPILE' 5212environment variable to the script, i. e. to use the ELDK cross tools 5213you can type 5214 5215 CROSS_COMPILE=ppc_8xx- MAKEALL 5216 5217or to build on a native PowerPC system you can type 5218 5219 CROSS_COMPILE=' ' MAKEALL 5220 5221When using the MAKEALL script, the default behaviour is to build 5222U-Boot in the source directory. This location can be changed by 5223setting the BUILD_DIR environment variable. Also, for each target 5224built, the MAKEALL script saves two log files (<target>.ERR and 5225<target>.MAKEALL) in the <source dir>/LOG directory. This default 5226location can be changed by setting the MAKEALL_LOGDIR environment 5227variable. For example: 5228 5229 export BUILD_DIR=/tmp/build 5230 export MAKEALL_LOGDIR=/tmp/log 5231 CROSS_COMPILE=ppc_8xx- MAKEALL 5232 5233With the above settings build objects are saved in the /tmp/build, 5234log files are saved in the /tmp/log and the source tree remains clean 5235during the whole build process. 5236 5237 5238See also "U-Boot Porting Guide" below. 5239 5240 5241Monitor Commands - Overview: 5242============================ 5243 5244go - start application at address 'addr' 5245run - run commands in an environment variable 5246bootm - boot application image from memory 5247bootp - boot image via network using BootP/TFTP protocol 5248bootz - boot zImage from memory 5249tftpboot- boot image via network using TFTP protocol 5250 and env variables "ipaddr" and "serverip" 5251 (and eventually "gatewayip") 5252tftpput - upload a file via network using TFTP protocol 5253rarpboot- boot image via network using RARP/TFTP protocol 5254diskboot- boot from IDE devicebootd - boot default, i.e., run 'bootcmd' 5255loads - load S-Record file over serial line 5256loadb - load binary file over serial line (kermit mode) 5257md - memory display 5258mm - memory modify (auto-incrementing) 5259nm - memory modify (constant address) 5260mw - memory write (fill) 5261cp - memory copy 5262cmp - memory compare 5263crc32 - checksum calculation 5264i2c - I2C sub-system 5265sspi - SPI utility commands 5266base - print or set address offset 5267printenv- print environment variables 5268setenv - set environment variables 5269saveenv - save environment variables to persistent storage 5270protect - enable or disable FLASH write protection 5271erase - erase FLASH memory 5272flinfo - print FLASH memory information 5273nand - NAND memory operations (see doc/README.nand) 5274bdinfo - print Board Info structure 5275iminfo - print header information for application image 5276coninfo - print console devices and informations 5277ide - IDE sub-system 5278loop - infinite loop on address range 5279loopw - infinite write loop on address range 5280mtest - simple RAM test 5281icache - enable or disable instruction cache 5282dcache - enable or disable data cache 5283reset - Perform RESET of the CPU 5284echo - echo args to console 5285version - print monitor version 5286help - print online help 5287? - alias for 'help' 5288 5289 5290Monitor Commands - Detailed Description: 5291======================================== 5292 5293TODO. 5294 5295For now: just type "help <command>". 5296 5297 5298Environment Variables: 5299====================== 5300 5301U-Boot supports user configuration using Environment Variables which 5302can be made persistent by saving to Flash memory. 5303 5304Environment Variables are set using "setenv", printed using 5305"printenv", and saved to Flash using "saveenv". Using "setenv" 5306without a value can be used to delete a variable from the 5307environment. As long as you don't save the environment you are 5308working with an in-memory copy. In case the Flash area containing the 5309environment is erased by accident, a default environment is provided. 5310 5311Some configuration options can be set using Environment Variables. 5312 5313List of environment variables (most likely not complete): 5314 5315 baudrate - see CONFIG_BAUDRATE 5316 5317 bootdelay - see CONFIG_BOOTDELAY 5318 5319 bootcmd - see CONFIG_BOOTCOMMAND 5320 5321 bootargs - Boot arguments when booting an RTOS image 5322 5323 bootfile - Name of the image to load with TFTP 5324 5325 bootm_low - Memory range available for image processing in the bootm 5326 command can be restricted. This variable is given as 5327 a hexadecimal number and defines lowest address allowed 5328 for use by the bootm command. See also "bootm_size" 5329 environment variable. Address defined by "bootm_low" is 5330 also the base of the initial memory mapping for the Linux 5331 kernel -- see the description of CONFIG_SYS_BOOTMAPSZ and 5332 bootm_mapsize. 5333 5334 bootm_mapsize - Size of the initial memory mapping for the Linux kernel. 5335 This variable is given as a hexadecimal number and it 5336 defines the size of the memory region starting at base 5337 address bootm_low that is accessible by the Linux kernel 5338 during early boot. If unset, CONFIG_SYS_BOOTMAPSZ is used 5339 as the default value if it is defined, and bootm_size is 5340 used otherwise. 5341 5342 bootm_size - Memory range available for image processing in the bootm 5343 command can be restricted. This variable is given as 5344 a hexadecimal number and defines the size of the region 5345 allowed for use by the bootm command. See also "bootm_low" 5346 environment variable. 5347 5348 updatefile - Location of the software update file on a TFTP server, used 5349 by the automatic software update feature. Please refer to 5350 documentation in doc/README.update for more details. 5351 5352 autoload - if set to "no" (any string beginning with 'n'), 5353 "bootp" will just load perform a lookup of the 5354 configuration from the BOOTP server, but not try to 5355 load any image using TFTP 5356 5357 autostart - if set to "yes", an image loaded using the "bootp", 5358 "rarpboot", "tftpboot" or "diskboot" commands will 5359 be automatically started (by internally calling 5360 "bootm") 5361 5362 If set to "no", a standalone image passed to the 5363 "bootm" command will be copied to the load address 5364 (and eventually uncompressed), but NOT be started. 5365 This can be used to load and uncompress arbitrary 5366 data. 5367 5368 fdt_high - if set this restricts the maximum address that the 5369 flattened device tree will be copied into upon boot. 5370 For example, if you have a system with 1 GB memory 5371 at physical address 0x10000000, while Linux kernel 5372 only recognizes the first 704 MB as low memory, you 5373 may need to set fdt_high as 0x3C000000 to have the 5374 device tree blob be copied to the maximum address 5375 of the 704 MB low memory, so that Linux kernel can 5376 access it during the boot procedure. 5377 5378 If this is set to the special value 0xFFFFFFFF then 5379 the fdt will not be copied at all on boot. For this 5380 to work it must reside in writable memory, have 5381 sufficient padding on the end of it for u-boot to 5382 add the information it needs into it, and the memory 5383 must be accessible by the kernel. 5384 5385 fdtcontroladdr- if set this is the address of the control flattened 5386 device tree used by U-Boot when CONFIG_OF_CONTROL is 5387 defined. 5388 5389 i2cfast - (PPC405GP|PPC405EP only) 5390 if set to 'y' configures Linux I2C driver for fast 5391 mode (400kHZ). This environment variable is used in 5392 initialization code. So, for changes to be effective 5393 it must be saved and board must be reset. 5394 5395 initrd_high - restrict positioning of initrd images: 5396 If this variable is not set, initrd images will be 5397 copied to the highest possible address in RAM; this 5398 is usually what you want since it allows for 5399 maximum initrd size. If for some reason you want to 5400 make sure that the initrd image is loaded below the 5401 CONFIG_SYS_BOOTMAPSZ limit, you can set this environment 5402 variable to a value of "no" or "off" or "0". 5403 Alternatively, you can set it to a maximum upper 5404 address to use (U-Boot will still check that it 5405 does not overwrite the U-Boot stack and data). 5406 5407 For instance, when you have a system with 16 MB 5408 RAM, and want to reserve 4 MB from use by Linux, 5409 you can do this by adding "mem=12M" to the value of 5410 the "bootargs" variable. However, now you must make 5411 sure that the initrd image is placed in the first 5412 12 MB as well - this can be done with 5413 5414 setenv initrd_high 00c00000 5415 5416 If you set initrd_high to 0xFFFFFFFF, this is an 5417 indication to U-Boot that all addresses are legal 5418 for the Linux kernel, including addresses in flash 5419 memory. In this case U-Boot will NOT COPY the 5420 ramdisk at all. This may be useful to reduce the 5421 boot time on your system, but requires that this 5422 feature is supported by your Linux kernel. 5423 5424 ipaddr - IP address; needed for tftpboot command 5425 5426 loadaddr - Default load address for commands like "bootp", 5427 "rarpboot", "tftpboot", "loadb" or "diskboot" 5428 5429 loads_echo - see CONFIG_LOADS_ECHO 5430 5431 serverip - TFTP server IP address; needed for tftpboot command 5432 5433 bootretry - see CONFIG_BOOT_RETRY_TIME 5434 5435 bootdelaykey - see CONFIG_AUTOBOOT_DELAY_STR 5436 5437 bootstopkey - see CONFIG_AUTOBOOT_STOP_STR 5438 5439 ethprime - controls which interface is used first. 5440 5441 ethact - controls which interface is currently active. 5442 For example you can do the following 5443 5444 => setenv ethact FEC 5445 => ping 192.168.0.1 # traffic sent on FEC 5446 => setenv ethact SCC 5447 => ping 10.0.0.1 # traffic sent on SCC 5448 5449 ethrotate - When set to "no" U-Boot does not go through all 5450 available network interfaces. 5451 It just stays at the currently selected interface. 5452 5453 netretry - When set to "no" each network operation will 5454 either succeed or fail without retrying. 5455 When set to "once" the network operation will 5456 fail when all the available network interfaces 5457 are tried once without success. 5458 Useful on scripts which control the retry operation 5459 themselves. 5460 5461 npe_ucode - set load address for the NPE microcode 5462 5463 silent_linux - If set then Linux will be told to boot silently, by 5464 changing the console to be empty. If "yes" it will be 5465 made silent. If "no" it will not be made silent. If 5466 unset, then it will be made silent if the U-Boot console 5467 is silent. 5468 5469 tftpsrcport - If this is set, the value is used for TFTP's 5470 UDP source port. 5471 5472 tftpdstport - If this is set, the value is used for TFTP's UDP 5473 destination port instead of the Well Know Port 69. 5474 5475 tftpblocksize - Block size to use for TFTP transfers; if not set, 5476 we use the TFTP server's default block size 5477 5478 tftptimeout - Retransmission timeout for TFTP packets (in milli- 5479 seconds, minimum value is 1000 = 1 second). Defines 5480 when a packet is considered to be lost so it has to 5481 be retransmitted. The default is 5000 = 5 seconds. 5482 Lowering this value may make downloads succeed 5483 faster in networks with high packet loss rates or 5484 with unreliable TFTP servers. 5485 5486 vlan - When set to a value < 4095 the traffic over 5487 Ethernet is encapsulated/received over 802.1q 5488 VLAN tagged frames. 5489 5490The following image location variables contain the location of images 5491used in booting. The "Image" column gives the role of the image and is 5492not an environment variable name. The other columns are environment 5493variable names. "File Name" gives the name of the file on a TFTP 5494server, "RAM Address" gives the location in RAM the image will be 5495loaded to, and "Flash Location" gives the image's address in NOR 5496flash or offset in NAND flash. 5497 5498*Note* - these variables don't have to be defined for all boards, some 5499boards currenlty use other variables for these purposes, and some 5500boards use these variables for other purposes. 5501 5502Image File Name RAM Address Flash Location 5503----- --------- ----------- -------------- 5504u-boot u-boot u-boot_addr_r u-boot_addr 5505Linux kernel bootfile kernel_addr_r kernel_addr 5506device tree blob fdtfile fdt_addr_r fdt_addr 5507ramdisk ramdiskfile ramdisk_addr_r ramdisk_addr 5508 5509The following environment variables may be used and automatically 5510updated by the network boot commands ("bootp" and "rarpboot"), 5511depending the information provided by your boot server: 5512 5513 bootfile - see above 5514 dnsip - IP address of your Domain Name Server 5515 dnsip2 - IP address of your secondary Domain Name Server 5516 gatewayip - IP address of the Gateway (Router) to use 5517 hostname - Target hostname 5518 ipaddr - see above 5519 netmask - Subnet Mask 5520 rootpath - Pathname of the root filesystem on the NFS server 5521 serverip - see above 5522 5523 5524There are two special Environment Variables: 5525 5526 serial# - contains hardware identification information such 5527 as type string and/or serial number 5528 ethaddr - Ethernet address 5529 5530These variables can be set only once (usually during manufacturing of 5531the board). U-Boot refuses to delete or overwrite these variables 5532once they have been set once. 5533 5534 5535Further special Environment Variables: 5536 5537 ver - Contains the U-Boot version string as printed 5538 with the "version" command. This variable is 5539 readonly (see CONFIG_VERSION_VARIABLE). 5540 5541 5542Please note that changes to some configuration parameters may take 5543only effect after the next boot (yes, that's just like Windoze :-). 5544 5545 5546Callback functions for environment variables: 5547--------------------------------------------- 5548 5549For some environment variables, the behavior of u-boot needs to change 5550when their values are changed. This functionality allows functions to 5551be associated with arbitrary variables. On creation, overwrite, or 5552deletion, the callback will provide the opportunity for some side 5553effect to happen or for the change to be rejected. 5554 5555The callbacks are named and associated with a function using the 5556U_BOOT_ENV_CALLBACK macro in your board or driver code. 5557 5558These callbacks are associated with variables in one of two ways. The 5559static list can be added to by defining CONFIG_ENV_CALLBACK_LIST_STATIC 5560in the board configuration to a string that defines a list of 5561associations. The list must be in the following format: 5562 5563 entry = variable_name[:callback_name] 5564 list = entry[,list] 5565 5566If the callback name is not specified, then the callback is deleted. 5567Spaces are also allowed anywhere in the list. 5568 5569Callbacks can also be associated by defining the ".callbacks" variable 5570with the same list format above. Any association in ".callbacks" will 5571override any association in the static list. You can define 5572CONFIG_ENV_CALLBACK_LIST_DEFAULT to a list (string) to define the 5573".callbacks" environment variable in the default or embedded environment. 5574 5575 5576Command Line Parsing: 5577===================== 5578 5579There are two different command line parsers available with U-Boot: 5580the old "simple" one, and the much more powerful "hush" shell: 5581 5582Old, simple command line parser: 5583-------------------------------- 5584 5585- supports environment variables (through setenv / saveenv commands) 5586- several commands on one line, separated by ';' 5587- variable substitution using "... ${name} ..." syntax 5588- special characters ('$', ';') can be escaped by prefixing with '\', 5589 for example: 5590 setenv bootcmd bootm \${address} 5591- You can also escape text by enclosing in single apostrophes, for example: 5592 setenv addip 'setenv bootargs $bootargs ip=$ipaddr:$serverip:$gatewayip:$netmask:$hostname::off' 5593 5594Hush shell: 5595----------- 5596 5597- similar to Bourne shell, with control structures like 5598 if...then...else...fi, for...do...done; while...do...done, 5599 until...do...done, ... 5600- supports environment ("global") variables (through setenv / saveenv 5601 commands) and local shell variables (through standard shell syntax 5602 "name=value"); only environment variables can be used with "run" 5603 command 5604 5605General rules: 5606-------------- 5607 5608(1) If a command line (or an environment variable executed by a "run" 5609 command) contains several commands separated by semicolon, and 5610 one of these commands fails, then the remaining commands will be 5611 executed anyway. 5612 5613(2) If you execute several variables with one call to run (i. e. 5614 calling run with a list of variables as arguments), any failing 5615 command will cause "run" to terminate, i. e. the remaining 5616 variables are not executed. 5617 5618Note for Redundant Ethernet Interfaces: 5619======================================= 5620 5621Some boards come with redundant Ethernet interfaces; U-Boot supports 5622such configurations and is capable of automatic selection of a 5623"working" interface when needed. MAC assignment works as follows: 5624 5625Network interfaces are numbered eth0, eth1, eth2, ... Corresponding 5626MAC addresses can be stored in the environment as "ethaddr" (=>eth0), 5627"eth1addr" (=>eth1), "eth2addr", ... 5628 5629If the network interface stores some valid MAC address (for instance 5630in SROM), this is used as default address if there is NO correspon- 5631ding setting in the environment; if the corresponding environment 5632variable is set, this overrides the settings in the card; that means: 5633 5634o If the SROM has a valid MAC address, and there is no address in the 5635 environment, the SROM's address is used. 5636 5637o If there is no valid address in the SROM, and a definition in the 5638 environment exists, then the value from the environment variable is 5639 used. 5640 5641o If both the SROM and the environment contain a MAC address, and 5642 both addresses are the same, this MAC address is used. 5643 5644o If both the SROM and the environment contain a MAC address, and the 5645 addresses differ, the value from the environment is used and a 5646 warning is printed. 5647 5648o If neither SROM nor the environment contain a MAC address, an error 5649 is raised. 5650 5651If Ethernet drivers implement the 'write_hwaddr' function, valid MAC addresses 5652will be programmed into hardware as part of the initialization process. This 5653may be skipped by setting the appropriate 'ethmacskip' environment variable. 5654The naming convention is as follows: 5655"ethmacskip" (=>eth0), "eth1macskip" (=>eth1) etc. 5656 5657Image Formats: 5658============== 5659 5660U-Boot is capable of booting (and performing other auxiliary operations on) 5661images in two formats: 5662 5663New uImage format (FIT) 5664----------------------- 5665 5666Flexible and powerful format based on Flattened Image Tree -- FIT (similar 5667to Flattened Device Tree). It allows the use of images with multiple 5668components (several kernels, ramdisks, etc.), with contents protected by 5669SHA1, MD5 or CRC32. More details are found in the doc/uImage.FIT directory. 5670 5671 5672Old uImage format 5673----------------- 5674 5675Old image format is based on binary files which can be basically anything, 5676preceded by a special header; see the definitions in include/image.h for 5677details; basically, the header defines the following image properties: 5678 5679* Target Operating System (Provisions for OpenBSD, NetBSD, FreeBSD, 5680 4.4BSD, Linux, SVR4, Esix, Solaris, Irix, SCO, Dell, NCR, VxWorks, 5681 LynxOS, pSOS, QNX, RTEMS, INTEGRITY; 5682 Currently supported: Linux, NetBSD, VxWorks, QNX, RTEMS, LynxOS, 5683 INTEGRITY). 5684* Target CPU Architecture (Provisions for Alpha, ARM, AVR32, Intel x86, 5685 IA64, MIPS, NDS32, Nios II, PowerPC, IBM S390, SuperH, Sparc, Sparc 64 Bit; 5686 Currently supported: ARM, AVR32, Intel x86, MIPS, NDS32, Nios II, PowerPC). 5687* Compression Type (uncompressed, gzip, bzip2) 5688* Load Address 5689* Entry Point 5690* Image Name 5691* Image Timestamp 5692 5693The header is marked by a special Magic Number, and both the header 5694and the data portions of the image are secured against corruption by 5695CRC32 checksums. 5696 5697 5698Linux Support: 5699============== 5700 5701Although U-Boot should support any OS or standalone application 5702easily, the main focus has always been on Linux during the design of 5703U-Boot. 5704 5705U-Boot includes many features that so far have been part of some 5706special "boot loader" code within the Linux kernel. Also, any 5707"initrd" images to be used are no longer part of one big Linux image; 5708instead, kernel and "initrd" are separate images. This implementation 5709serves several purposes: 5710 5711- the same features can be used for other OS or standalone 5712 applications (for instance: using compressed images to reduce the 5713 Flash memory footprint) 5714 5715- it becomes much easier to port new Linux kernel versions because 5716 lots of low-level, hardware dependent stuff are done by U-Boot 5717 5718- the same Linux kernel image can now be used with different "initrd" 5719 images; of course this also means that different kernel images can 5720 be run with the same "initrd". This makes testing easier (you don't 5721 have to build a new "zImage.initrd" Linux image when you just 5722 change a file in your "initrd"). Also, a field-upgrade of the 5723 software is easier now. 5724 5725 5726Linux HOWTO: 5727============ 5728 5729Porting Linux to U-Boot based systems: 5730--------------------------------------- 5731 5732U-Boot cannot save you from doing all the necessary modifications to 5733configure the Linux device drivers for use with your target hardware 5734(no, we don't intend to provide a full virtual machine interface to 5735Linux :-). 5736 5737But now you can ignore ALL boot loader code (in arch/powerpc/mbxboot). 5738 5739Just make sure your machine specific header file (for instance 5740include/asm-ppc/tqm8xx.h) includes the same definition of the Board 5741Information structure as we define in include/asm-<arch>/u-boot.h, 5742and make sure that your definition of IMAP_ADDR uses the same value 5743as your U-Boot configuration in CONFIG_SYS_IMMR. 5744 5745Note that U-Boot now has a driver model, a unified model for drivers. 5746If you are adding a new driver, plumb it into driver model. If there 5747is no uclass available, you are encouraged to create one. See 5748doc/driver-model. 5749 5750 5751Configuring the Linux kernel: 5752----------------------------- 5753 5754No specific requirements for U-Boot. Make sure you have some root 5755device (initial ramdisk, NFS) for your target system. 5756 5757 5758Building a Linux Image: 5759----------------------- 5760 5761With U-Boot, "normal" build targets like "zImage" or "bzImage" are 5762not used. If you use recent kernel source, a new build target 5763"uImage" will exist which automatically builds an image usable by 5764U-Boot. Most older kernels also have support for a "pImage" target, 5765which was introduced for our predecessor project PPCBoot and uses a 5766100% compatible format. 5767 5768Example: 5769 5770 make TQM850L_defconfig 5771 make oldconfig 5772 make dep 5773 make uImage 5774 5775The "uImage" build target uses a special tool (in 'tools/mkimage') to 5776encapsulate a compressed Linux kernel image with header information, 5777CRC32 checksum etc. for use with U-Boot. This is what we are doing: 5778 5779* build a standard "vmlinux" kernel image (in ELF binary format): 5780 5781* convert the kernel into a raw binary image: 5782 5783 ${CROSS_COMPILE}-objcopy -O binary \ 5784 -R .note -R .comment \ 5785 -S vmlinux linux.bin 5786 5787* compress the binary image: 5788 5789 gzip -9 linux.bin 5790 5791* package compressed binary image for U-Boot: 5792 5793 mkimage -A ppc -O linux -T kernel -C gzip \ 5794 -a 0 -e 0 -n "Linux Kernel Image" \ 5795 -d linux.bin.gz uImage 5796 5797 5798The "mkimage" tool can also be used to create ramdisk images for use 5799with U-Boot, either separated from the Linux kernel image, or 5800combined into one file. "mkimage" encapsulates the images with a 64 5801byte header containing information about target architecture, 5802operating system, image type, compression method, entry points, time 5803stamp, CRC32 checksums, etc. 5804 5805"mkimage" can be called in two ways: to verify existing images and 5806print the header information, or to build new images. 5807 5808In the first form (with "-l" option) mkimage lists the information 5809contained in the header of an existing U-Boot image; this includes 5810checksum verification: 5811 5812 tools/mkimage -l image 5813 -l ==> list image header information 5814 5815The second form (with "-d" option) is used to build a U-Boot image 5816from a "data file" which is used as image payload: 5817 5818 tools/mkimage -A arch -O os -T type -C comp -a addr -e ep \ 5819 -n name -d data_file image 5820 -A ==> set architecture to 'arch' 5821 -O ==> set operating system to 'os' 5822 -T ==> set image type to 'type' 5823 -C ==> set compression type 'comp' 5824 -a ==> set load address to 'addr' (hex) 5825 -e ==> set entry point to 'ep' (hex) 5826 -n ==> set image name to 'name' 5827 -d ==> use image data from 'datafile' 5828 5829Right now, all Linux kernels for PowerPC systems use the same load 5830address (0x00000000), but the entry point address depends on the 5831kernel version: 5832 5833- 2.2.x kernels have the entry point at 0x0000000C, 5834- 2.3.x and later kernels have the entry point at 0x00000000. 5835 5836So a typical call to build a U-Boot image would read: 5837 5838 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \ 5839 > -A ppc -O linux -T kernel -C gzip -a 0 -e 0 \ 5840 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux.gz \ 5841 > examples/uImage.TQM850L 5842 Image Name: 2.4.4 kernel for TQM850L 5843 Created: Wed Jul 19 02:34:59 2000 5844 Image Type: PowerPC Linux Kernel Image (gzip compressed) 5845 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB 5846 Load Address: 0x00000000 5847 Entry Point: 0x00000000 5848 5849To verify the contents of the image (or check for corruption): 5850 5851 -> tools/mkimage -l examples/uImage.TQM850L 5852 Image Name: 2.4.4 kernel for TQM850L 5853 Created: Wed Jul 19 02:34:59 2000 5854 Image Type: PowerPC Linux Kernel Image (gzip compressed) 5855 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB 5856 Load Address: 0x00000000 5857 Entry Point: 0x00000000 5858 5859NOTE: for embedded systems where boot time is critical you can trade 5860speed for memory and install an UNCOMPRESSED image instead: this 5861needs more space in Flash, but boots much faster since it does not 5862need to be uncompressed: 5863 5864 -> gunzip /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux.gz 5865 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \ 5866 > -A ppc -O linux -T kernel -C none -a 0 -e 0 \ 5867 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux \ 5868 > examples/uImage.TQM850L-uncompressed 5869 Image Name: 2.4.4 kernel for TQM850L 5870 Created: Wed Jul 19 02:34:59 2000 5871 Image Type: PowerPC Linux Kernel Image (uncompressed) 5872 Data Size: 792160 Bytes = 773.59 kB = 0.76 MB 5873 Load Address: 0x00000000 5874 Entry Point: 0x00000000 5875 5876 5877Similar you can build U-Boot images from a 'ramdisk.image.gz' file 5878when your kernel is intended to use an initial ramdisk: 5879 5880 -> tools/mkimage -n 'Simple Ramdisk Image' \ 5881 > -A ppc -O linux -T ramdisk -C gzip \ 5882 > -d /LinuxPPC/images/SIMPLE-ramdisk.image.gz examples/simple-initrd 5883 Image Name: Simple Ramdisk Image 5884 Created: Wed Jan 12 14:01:50 2000 5885 Image Type: PowerPC Linux RAMDisk Image (gzip compressed) 5886 Data Size: 566530 Bytes = 553.25 kB = 0.54 MB 5887 Load Address: 0x00000000 5888 Entry Point: 0x00000000 5889 5890The "dumpimage" is a tool to disassemble images built by mkimage. Its "-i" 5891option performs the converse operation of the mkimage's second form (the "-d" 5892option). Given an image built by mkimage, the dumpimage extracts a "data file" 5893from the image: 5894 5895 tools/dumpimage -i image -T type -p position data_file 5896 -i ==> extract from the 'image' a specific 'data_file' 5897 -T ==> set image type to 'type' 5898 -p ==> 'position' (starting at 0) of the 'data_file' inside the 'image' 5899 5900 5901Installing a Linux Image: 5902------------------------- 5903 5904To downloading a U-Boot image over the serial (console) interface, 5905you must convert the image to S-Record format: 5906 5907 objcopy -I binary -O srec examples/image examples/image.srec 5908 5909The 'objcopy' does not understand the information in the U-Boot 5910image header, so the resulting S-Record file will be relative to 5911address 0x00000000. To load it to a given address, you need to 5912specify the target address as 'offset' parameter with the 'loads' 5913command. 5914 5915Example: install the image to address 0x40100000 (which on the 5916TQM8xxL is in the first Flash bank): 5917 5918 => erase 40100000 401FFFFF 5919 5920 .......... done 5921 Erased 8 sectors 5922 5923 => loads 40100000 5924 ## Ready for S-Record download ... 5925 ~>examples/image.srec 5926 1 2 3 4 5 6 7 8 9 10 11 12 13 ... 5927 ... 5928 15989 15990 15991 15992 5929 [file transfer complete] 5930 [connected] 5931 ## Start Addr = 0x00000000 5932 5933 5934You can check the success of the download using the 'iminfo' command; 5935this includes a checksum verification so you can be sure no data 5936corruption happened: 5937 5938 => imi 40100000 5939 5940 ## Checking Image at 40100000 ... 5941 Image Name: 2.2.13 for initrd on TQM850L 5942 Image Type: PowerPC Linux Kernel Image (gzip compressed) 5943 Data Size: 335725 Bytes = 327 kB = 0 MB 5944 Load Address: 00000000 5945 Entry Point: 0000000c 5946 Verifying Checksum ... OK 5947 5948 5949Boot Linux: 5950----------- 5951 5952The "bootm" command is used to boot an application that is stored in 5953memory (RAM or Flash). In case of a Linux kernel image, the contents 5954of the "bootargs" environment variable is passed to the kernel as 5955parameters. You can check and modify this variable using the 5956"printenv" and "setenv" commands: 5957 5958 5959 => printenv bootargs 5960 bootargs=root=/dev/ram 5961 5962 => setenv bootargs root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2 5963 5964 => printenv bootargs 5965 bootargs=root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2 5966 5967 => bootm 40020000 5968 ## Booting Linux kernel at 40020000 ... 5969 Image Name: 2.2.13 for NFS on TQM850L 5970 Image Type: PowerPC Linux Kernel Image (gzip compressed) 5971 Data Size: 381681 Bytes = 372 kB = 0 MB 5972 Load Address: 00000000 5973 Entry Point: 0000000c 5974 Verifying Checksum ... OK 5975 Uncompressing Kernel Image ... OK 5976 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 5977 Boot arguments: root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2 5978 time_init: decrementer frequency = 187500000/60 5979 Calibrating delay loop... 49.77 BogoMIPS 5980 Memory: 15208k available (700k kernel code, 444k data, 32k init) [c0000000,c1000000] 5981 ... 5982 5983If you want to boot a Linux kernel with initial RAM disk, you pass 5984the memory addresses of both the kernel and the initrd image (PPBCOOT 5985format!) to the "bootm" command: 5986 5987 => imi 40100000 40200000 5988 5989 ## Checking Image at 40100000 ... 5990 Image Name: 2.2.13 for initrd on TQM850L 5991 Image Type: PowerPC Linux Kernel Image (gzip compressed) 5992 Data Size: 335725 Bytes = 327 kB = 0 MB 5993 Load Address: 00000000 5994 Entry Point: 0000000c 5995 Verifying Checksum ... OK 5996 5997 ## Checking Image at 40200000 ... 5998 Image Name: Simple Ramdisk Image 5999 Image Type: PowerPC Linux RAMDisk Image (gzip compressed) 6000 Data Size: 566530 Bytes = 553 kB = 0 MB 6001 Load Address: 00000000 6002 Entry Point: 00000000 6003 Verifying Checksum ... OK 6004 6005 => bootm 40100000 40200000 6006 ## Booting Linux kernel at 40100000 ... 6007 Image Name: 2.2.13 for initrd on TQM850L 6008 Image Type: PowerPC Linux Kernel Image (gzip compressed) 6009 Data Size: 335725 Bytes = 327 kB = 0 MB 6010 Load Address: 00000000 6011 Entry Point: 0000000c 6012 Verifying Checksum ... OK 6013 Uncompressing Kernel Image ... OK 6014 ## Loading RAMDisk Image at 40200000 ... 6015 Image Name: Simple Ramdisk Image 6016 Image Type: PowerPC Linux RAMDisk Image (gzip compressed) 6017 Data Size: 566530 Bytes = 553 kB = 0 MB 6018 Load Address: 00000000 6019 Entry Point: 00000000 6020 Verifying Checksum ... OK 6021 Loading Ramdisk ... OK 6022 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 6023 Boot arguments: root=/dev/ram 6024 time_init: decrementer frequency = 187500000/60 6025 Calibrating delay loop... 49.77 BogoMIPS 6026 ... 6027 RAMDISK: Compressed image found at block 0 6028 VFS: Mounted root (ext2 filesystem). 6029 6030 bash# 6031 6032Boot Linux and pass a flat device tree: 6033----------- 6034 6035First, U-Boot must be compiled with the appropriate defines. See the section 6036titled "Linux Kernel Interface" above for a more in depth explanation. The 6037following is an example of how to start a kernel and pass an updated 6038flat device tree: 6039 6040=> print oftaddr 6041oftaddr=0x300000 6042=> print oft 6043oft=oftrees/mpc8540ads.dtb 6044=> tftp $oftaddr $oft 6045Speed: 1000, full duplex 6046Using TSEC0 device 6047TFTP from server 192.168.1.1; our IP address is 192.168.1.101 6048Filename 'oftrees/mpc8540ads.dtb'. 6049Load address: 0x300000 6050Loading: # 6051done 6052Bytes transferred = 4106 (100a hex) 6053=> tftp $loadaddr $bootfile 6054Speed: 1000, full duplex 6055Using TSEC0 device 6056TFTP from server 192.168.1.1; our IP address is 192.168.1.2 6057Filename 'uImage'. 6058Load address: 0x200000 6059Loading:############ 6060done 6061Bytes transferred = 1029407 (fb51f hex) 6062=> print loadaddr 6063loadaddr=200000 6064=> print oftaddr 6065oftaddr=0x300000 6066=> bootm $loadaddr - $oftaddr 6067## Booting image at 00200000 ... 6068 Image Name: Linux-2.6.17-dirty 6069 Image Type: PowerPC Linux Kernel Image (gzip compressed) 6070 Data Size: 1029343 Bytes = 1005.2 kB 6071 Load Address: 00000000 6072 Entry Point: 00000000 6073 Verifying Checksum ... OK 6074 Uncompressing Kernel Image ... OK 6075Booting using flat device tree at 0x300000 6076Using MPC85xx ADS machine description 6077Memory CAM mapping: CAM0=256Mb, CAM1=256Mb, CAM2=0Mb residual: 0Mb 6078[snip] 6079 6080 6081More About U-Boot Image Types: 6082------------------------------ 6083 6084U-Boot supports the following image types: 6085 6086 "Standalone Programs" are directly runnable in the environment 6087 provided by U-Boot; it is expected that (if they behave 6088 well) you can continue to work in U-Boot after return from 6089 the Standalone Program. 6090 "OS Kernel Images" are usually images of some Embedded OS which 6091 will take over control completely. Usually these programs 6092 will install their own set of exception handlers, device 6093 drivers, set up the MMU, etc. - this means, that you cannot 6094 expect to re-enter U-Boot except by resetting the CPU. 6095 "RAMDisk Images" are more or less just data blocks, and their 6096 parameters (address, size) are passed to an OS kernel that is 6097 being started. 6098 "Multi-File Images" contain several images, typically an OS 6099 (Linux) kernel image and one or more data images like 6100 RAMDisks. This construct is useful for instance when you want 6101 to boot over the network using BOOTP etc., where the boot 6102 server provides just a single image file, but you want to get 6103 for instance an OS kernel and a RAMDisk image. 6104 6105 "Multi-File Images" start with a list of image sizes, each 6106 image size (in bytes) specified by an "uint32_t" in network 6107 byte order. This list is terminated by an "(uint32_t)0". 6108 Immediately after the terminating 0 follow the images, one by 6109 one, all aligned on "uint32_t" boundaries (size rounded up to 6110 a multiple of 4 bytes). 6111 6112 "Firmware Images" are binary images containing firmware (like 6113 U-Boot or FPGA images) which usually will be programmed to 6114 flash memory. 6115 6116 "Script files" are command sequences that will be executed by 6117 U-Boot's command interpreter; this feature is especially 6118 useful when you configure U-Boot to use a real shell (hush) 6119 as command interpreter. 6120 6121Booting the Linux zImage: 6122------------------------- 6123 6124On some platforms, it's possible to boot Linux zImage. This is done 6125using the "bootz" command. The syntax of "bootz" command is the same 6126as the syntax of "bootm" command. 6127 6128Note, defining the CONFIG_SUPPORT_RAW_INITRD allows user to supply 6129kernel with raw initrd images. The syntax is slightly different, the 6130address of the initrd must be augmented by it's size, in the following 6131format: "<initrd addres>:<initrd size>". 6132 6133 6134Standalone HOWTO: 6135================= 6136 6137One of the features of U-Boot is that you can dynamically load and 6138run "standalone" applications, which can use some resources of 6139U-Boot like console I/O functions or interrupt services. 6140 6141Two simple examples are included with the sources: 6142 6143"Hello World" Demo: 6144------------------- 6145 6146'examples/hello_world.c' contains a small "Hello World" Demo 6147application; it is automatically compiled when you build U-Boot. 6148It's configured to run at address 0x00040004, so you can play with it 6149like that: 6150 6151 => loads 6152 ## Ready for S-Record download ... 6153 ~>examples/hello_world.srec 6154 1 2 3 4 5 6 7 8 9 10 11 ... 6155 [file transfer complete] 6156 [connected] 6157 ## Start Addr = 0x00040004 6158 6159 => go 40004 Hello World! This is a test. 6160 ## Starting application at 0x00040004 ... 6161 Hello World 6162 argc = 7 6163 argv[0] = "40004" 6164 argv[1] = "Hello" 6165 argv[2] = "World!" 6166 argv[3] = "This" 6167 argv[4] = "is" 6168 argv[5] = "a" 6169 argv[6] = "test." 6170 argv[7] = "<NULL>" 6171 Hit any key to exit ... 6172 6173 ## Application terminated, rc = 0x0 6174 6175Another example, which demonstrates how to register a CPM interrupt 6176handler with the U-Boot code, can be found in 'examples/timer.c'. 6177Here, a CPM timer is set up to generate an interrupt every second. 6178The interrupt service routine is trivial, just printing a '.' 6179character, but this is just a demo program. The application can be 6180controlled by the following keys: 6181 6182 ? - print current values og the CPM Timer registers 6183 b - enable interrupts and start timer 6184 e - stop timer and disable interrupts 6185 q - quit application 6186 6187 => loads 6188 ## Ready for S-Record download ... 6189 ~>examples/timer.srec 6190 1 2 3 4 5 6 7 8 9 10 11 ... 6191 [file transfer complete] 6192 [connected] 6193 ## Start Addr = 0x00040004 6194 6195 => go 40004 6196 ## Starting application at 0x00040004 ... 6197 TIMERS=0xfff00980 6198 Using timer 1 6199 tgcr @ 0xfff00980, tmr @ 0xfff00990, trr @ 0xfff00994, tcr @ 0xfff00998, tcn @ 0xfff0099c, ter @ 0xfff009b0 6200 6201Hit 'b': 6202 [q, b, e, ?] Set interval 1000000 us 6203 Enabling timer 6204Hit '?': 6205 [q, b, e, ?] ........ 6206 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0xef6, ter=0x0 6207Hit '?': 6208 [q, b, e, ?] . 6209 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x2ad4, ter=0x0 6210Hit '?': 6211 [q, b, e, ?] . 6212 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x1efc, ter=0x0 6213Hit '?': 6214 [q, b, e, ?] . 6215 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x169d, ter=0x0 6216Hit 'e': 6217 [q, b, e, ?] ...Stopping timer 6218Hit 'q': 6219 [q, b, e, ?] ## Application terminated, rc = 0x0 6220 6221 6222Minicom warning: 6223================ 6224 6225Over time, many people have reported problems when trying to use the 6226"minicom" terminal emulation program for serial download. I (wd) 6227consider minicom to be broken, and recommend not to use it. Under 6228Unix, I recommend to use C-Kermit for general purpose use (and 6229especially for kermit binary protocol download ("loadb" command), and 6230use "cu" for S-Record download ("loads" command). See 6231http://www.denx.de/wiki/view/DULG/SystemSetup#Section_4.3. 6232for help with kermit. 6233 6234 6235Nevertheless, if you absolutely want to use it try adding this 6236configuration to your "File transfer protocols" section: 6237 6238 Name Program Name U/D FullScr IO-Red. Multi 6239 X kermit /usr/bin/kermit -i -l %l -s Y U Y N N 6240 Y kermit /usr/bin/kermit -i -l %l -r N D Y N N 6241 6242 6243NetBSD Notes: 6244============= 6245 6246Starting at version 0.9.2, U-Boot supports NetBSD both as host 6247(build U-Boot) and target system (boots NetBSD/mpc8xx). 6248 6249Building requires a cross environment; it is known to work on 6250NetBSD/i386 with the cross-powerpc-netbsd-1.3 package (you will also 6251need gmake since the Makefiles are not compatible with BSD make). 6252Note that the cross-powerpc package does not install include files; 6253attempting to build U-Boot will fail because <machine/ansi.h> is 6254missing. This file has to be installed and patched manually: 6255 6256 # cd /usr/pkg/cross/powerpc-netbsd/include 6257 # mkdir powerpc 6258 # ln -s powerpc machine 6259 # cp /usr/src/sys/arch/powerpc/include/ansi.h powerpc/ansi.h 6260 # ${EDIT} powerpc/ansi.h ## must remove __va_list, _BSD_VA_LIST 6261 6262Native builds *don't* work due to incompatibilities between native 6263and U-Boot include files. 6264 6265Booting assumes that (the first part of) the image booted is a 6266stage-2 loader which in turn loads and then invokes the kernel 6267proper. Loader sources will eventually appear in the NetBSD source 6268tree (probably in sys/arc/mpc8xx/stand/u-boot_stage2/); in the 6269meantime, see ftp://ftp.denx.de/pub/u-boot/ppcboot_stage2.tar.gz 6270 6271 6272Implementation Internals: 6273========================= 6274 6275The following is not intended to be a complete description of every 6276implementation detail. However, it should help to understand the 6277inner workings of U-Boot and make it easier to port it to custom 6278hardware. 6279 6280 6281Initial Stack, Global Data: 6282--------------------------- 6283 6284The implementation of U-Boot is complicated by the fact that U-Boot 6285starts running out of ROM (flash memory), usually without access to 6286system RAM (because the memory controller is not initialized yet). 6287This means that we don't have writable Data or BSS segments, and BSS 6288is not initialized as zero. To be able to get a C environment working 6289at all, we have to allocate at least a minimal stack. Implementation 6290options for this are defined and restricted by the CPU used: Some CPU 6291models provide on-chip memory (like the IMMR area on MPC8xx and 6292MPC826x processors), on others (parts of) the data cache can be 6293locked as (mis-) used as memory, etc. 6294 6295 Chris Hallinan posted a good summary of these issues to the 6296 U-Boot mailing list: 6297 6298 Subject: RE: [U-Boot-Users] RE: More On Memory Bank x (nothingness)? 6299 From: "Chris Hallinan" <clh@net1plus.com> 6300 Date: Mon, 10 Feb 2003 16:43:46 -0500 (22:43 MET) 6301 ... 6302 6303 Correct me if I'm wrong, folks, but the way I understand it 6304 is this: Using DCACHE as initial RAM for Stack, etc, does not 6305 require any physical RAM backing up the cache. The cleverness 6306 is that the cache is being used as a temporary supply of 6307 necessary storage before the SDRAM controller is setup. It's 6308 beyond the scope of this list to explain the details, but you 6309 can see how this works by studying the cache architecture and 6310 operation in the architecture and processor-specific manuals. 6311 6312 OCM is On Chip Memory, which I believe the 405GP has 4K. It 6313 is another option for the system designer to use as an 6314 initial stack/RAM area prior to SDRAM being available. Either 6315 option should work for you. Using CS 4 should be fine if your 6316 board designers haven't used it for something that would 6317 cause you grief during the initial boot! It is frequently not 6318 used. 6319 6320 CONFIG_SYS_INIT_RAM_ADDR should be somewhere that won't interfere 6321 with your processor/board/system design. The default value 6322 you will find in any recent u-boot distribution in 6323 walnut.h should work for you. I'd set it to a value larger 6324 than your SDRAM module. If you have a 64MB SDRAM module, set 6325 it above 400_0000. Just make sure your board has no resources 6326 that are supposed to respond to that address! That code in 6327 start.S has been around a while and should work as is when 6328 you get the config right. 6329 6330 -Chris Hallinan 6331 DS4.COM, Inc. 6332 6333It is essential to remember this, since it has some impact on the C 6334code for the initialization procedures: 6335 6336* Initialized global data (data segment) is read-only. Do not attempt 6337 to write it. 6338 6339* Do not use any uninitialized global data (or implicitly initialized 6340 as zero data - BSS segment) at all - this is undefined, initiali- 6341 zation is performed later (when relocating to RAM). 6342 6343* Stack space is very limited. Avoid big data buffers or things like 6344 that. 6345 6346Having only the stack as writable memory limits means we cannot use 6347normal global data to share information between the code. But it 6348turned out that the implementation of U-Boot can be greatly 6349simplified by making a global data structure (gd_t) available to all 6350functions. We could pass a pointer to this data as argument to _all_ 6351functions, but this would bloat the code. Instead we use a feature of 6352the GCC compiler (Global Register Variables) to share the data: we 6353place a pointer (gd) to the global data into a register which we 6354reserve for this purpose. 6355 6356When choosing a register for such a purpose we are restricted by the 6357relevant (E)ABI specifications for the current architecture, and by 6358GCC's implementation. 6359 6360For PowerPC, the following registers have specific use: 6361 R1: stack pointer 6362 R2: reserved for system use 6363 R3-R4: parameter passing and return values 6364 R5-R10: parameter passing 6365 R13: small data area pointer 6366 R30: GOT pointer 6367 R31: frame pointer 6368 6369 (U-Boot also uses R12 as internal GOT pointer. r12 6370 is a volatile register so r12 needs to be reset when 6371 going back and forth between asm and C) 6372 6373 ==> U-Boot will use R2 to hold a pointer to the global data 6374 6375 Note: on PPC, we could use a static initializer (since the 6376 address of the global data structure is known at compile time), 6377 but it turned out that reserving a register results in somewhat 6378 smaller code - although the code savings are not that big (on 6379 average for all boards 752 bytes for the whole U-Boot image, 6380 624 text + 127 data). 6381 6382On Blackfin, the normal C ABI (except for P3) is followed as documented here: 6383 http://docs.blackfin.uclinux.org/doku.php?id=application_binary_interface 6384 6385 ==> U-Boot will use P3 to hold a pointer to the global data 6386 6387On ARM, the following registers are used: 6388 6389 R0: function argument word/integer result 6390 R1-R3: function argument word 6391 R9: platform specific 6392 R10: stack limit (used only if stack checking is enabled) 6393 R11: argument (frame) pointer 6394 R12: temporary workspace 6395 R13: stack pointer 6396 R14: link register 6397 R15: program counter 6398 6399 ==> U-Boot will use R9 to hold a pointer to the global data 6400 6401 Note: on ARM, only R_ARM_RELATIVE relocations are supported. 6402 6403On Nios II, the ABI is documented here: 6404 http://www.altera.com/literature/hb/nios2/n2cpu_nii51016.pdf 6405 6406 ==> U-Boot will use gp to hold a pointer to the global data 6407 6408 Note: on Nios II, we give "-G0" option to gcc and don't use gp 6409 to access small data sections, so gp is free. 6410 6411On NDS32, the following registers are used: 6412 6413 R0-R1: argument/return 6414 R2-R5: argument 6415 R15: temporary register for assembler 6416 R16: trampoline register 6417 R28: frame pointer (FP) 6418 R29: global pointer (GP) 6419 R30: link register (LP) 6420 R31: stack pointer (SP) 6421 PC: program counter (PC) 6422 6423 ==> U-Boot will use R10 to hold a pointer to the global data 6424 6425NOTE: DECLARE_GLOBAL_DATA_PTR must be used with file-global scope, 6426or current versions of GCC may "optimize" the code too much. 6427 6428Memory Management: 6429------------------ 6430 6431U-Boot runs in system state and uses physical addresses, i.e. the 6432MMU is not used either for address mapping nor for memory protection. 6433 6434The available memory is mapped to fixed addresses using the memory 6435controller. In this process, a contiguous block is formed for each 6436memory type (Flash, SDRAM, SRAM), even when it consists of several 6437physical memory banks. 6438 6439U-Boot is installed in the first 128 kB of the first Flash bank (on 6440TQM8xxL modules this is the range 0x40000000 ... 0x4001FFFF). After 6441booting and sizing and initializing DRAM, the code relocates itself 6442to the upper end of DRAM. Immediately below the U-Boot code some 6443memory is reserved for use by malloc() [see CONFIG_SYS_MALLOC_LEN 6444configuration setting]. Below that, a structure with global Board 6445Info data is placed, followed by the stack (growing downward). 6446 6447Additionally, some exception handler code is copied to the low 8 kB 6448of DRAM (0x00000000 ... 0x00001FFF). 6449 6450So a typical memory configuration with 16 MB of DRAM could look like 6451this: 6452 6453 0x0000 0000 Exception Vector code 6454 : 6455 0x0000 1FFF 6456 0x0000 2000 Free for Application Use 6457 : 6458 : 6459 6460 : 6461 : 6462 0x00FB FF20 Monitor Stack (Growing downward) 6463 0x00FB FFAC Board Info Data and permanent copy of global data 6464 0x00FC 0000 Malloc Arena 6465 : 6466 0x00FD FFFF 6467 0x00FE 0000 RAM Copy of Monitor Code 6468 ... eventually: LCD or video framebuffer 6469 ... eventually: pRAM (Protected RAM - unchanged by reset) 6470 0x00FF FFFF [End of RAM] 6471 6472 6473System Initialization: 6474---------------------- 6475 6476In the reset configuration, U-Boot starts at the reset entry point 6477(on most PowerPC systems at address 0x00000100). Because of the reset 6478configuration for CS0# this is a mirror of the on board Flash memory. 6479To be able to re-map memory U-Boot then jumps to its link address. 6480To be able to implement the initialization code in C, a (small!) 6481initial stack is set up in the internal Dual Ported RAM (in case CPUs 6482which provide such a feature like MPC8xx or MPC8260), or in a locked 6483part of the data cache. After that, U-Boot initializes the CPU core, 6484the caches and the SIU. 6485 6486Next, all (potentially) available memory banks are mapped using a 6487preliminary mapping. For example, we put them on 512 MB boundaries 6488(multiples of 0x20000000: SDRAM on 0x00000000 and 0x20000000, Flash 6489on 0x40000000 and 0x60000000, SRAM on 0x80000000). Then UPM A is 6490programmed for SDRAM access. Using the temporary configuration, a 6491simple memory test is run that determines the size of the SDRAM 6492banks. 6493 6494When there is more than one SDRAM bank, and the banks are of 6495different size, the largest is mapped first. For equal size, the first 6496bank (CS2#) is mapped first. The first mapping is always for address 64970x00000000, with any additional banks following immediately to create 6498contiguous memory starting from 0. 6499 6500Then, the monitor installs itself at the upper end of the SDRAM area 6501and allocates memory for use by malloc() and for the global Board 6502Info data; also, the exception vector code is copied to the low RAM 6503pages, and the final stack is set up. 6504 6505Only after this relocation will you have a "normal" C environment; 6506until that you are restricted in several ways, mostly because you are 6507running from ROM, and because the code will have to be relocated to a 6508new address in RAM. 6509 6510 6511U-Boot Porting Guide: 6512---------------------- 6513 6514[Based on messages by Jerry Van Baren in the U-Boot-Users mailing 6515list, October 2002] 6516 6517 6518int main(int argc, char *argv[]) 6519{ 6520 sighandler_t no_more_time; 6521 6522 signal(SIGALRM, no_more_time); 6523 alarm(PROJECT_DEADLINE - toSec (3 * WEEK)); 6524 6525 if (available_money > available_manpower) { 6526 Pay consultant to port U-Boot; 6527 return 0; 6528 } 6529 6530 Download latest U-Boot source; 6531 6532 Subscribe to u-boot mailing list; 6533 6534 if (clueless) 6535 email("Hi, I am new to U-Boot, how do I get started?"); 6536 6537 while (learning) { 6538 Read the README file in the top level directory; 6539 Read http://www.denx.de/twiki/bin/view/DULG/Manual; 6540 Read applicable doc/*.README; 6541 Read the source, Luke; 6542 /* find . -name "*.[chS]" | xargs grep -i <keyword> */ 6543 } 6544 6545 if (available_money > toLocalCurrency ($2500)) 6546 Buy a BDI3000; 6547 else 6548 Add a lot of aggravation and time; 6549 6550 if (a similar board exists) { /* hopefully... */ 6551 cp -a board/<similar> board/<myboard> 6552 cp include/configs/<similar>.h include/configs/<myboard>.h 6553 } else { 6554 Create your own board support subdirectory; 6555 Create your own board include/configs/<myboard>.h file; 6556 } 6557 Edit new board/<myboard> files 6558 Edit new include/configs/<myboard>.h 6559 6560 while (!accepted) { 6561 while (!running) { 6562 do { 6563 Add / modify source code; 6564 } until (compiles); 6565 Debug; 6566 if (clueless) 6567 email("Hi, I am having problems..."); 6568 } 6569 Send patch file to the U-Boot email list; 6570 if (reasonable critiques) 6571 Incorporate improvements from email list code review; 6572 else 6573 Defend code as written; 6574 } 6575 6576 return 0; 6577} 6578 6579void no_more_time (int sig) 6580{ 6581 hire_a_guru(); 6582} 6583 6584 6585Coding Standards: 6586----------------- 6587 6588All contributions to U-Boot should conform to the Linux kernel 6589coding style; see the file "Documentation/CodingStyle" and the script 6590"scripts/Lindent" in your Linux kernel source directory. 6591 6592Source files originating from a different project (for example the 6593MTD subsystem) are generally exempt from these guidelines and are not 6594reformatted to ease subsequent migration to newer versions of those 6595sources. 6596 6597Please note that U-Boot is implemented in C (and to some small parts in 6598Assembler); no C++ is used, so please do not use C++ style comments (//) 6599in your code. 6600 6601Please also stick to the following formatting rules: 6602- remove any trailing white space 6603- use TAB characters for indentation and vertical alignment, not spaces 6604- make sure NOT to use DOS '\r\n' line feeds 6605- do not add more than 2 consecutive empty lines to source files 6606- do not add trailing empty lines to source files 6607 6608Submissions which do not conform to the standards may be returned 6609with a request to reformat the changes. 6610 6611 6612Submitting Patches: 6613------------------- 6614 6615Since the number of patches for U-Boot is growing, we need to 6616establish some rules. Submissions which do not conform to these rules 6617may be rejected, even when they contain important and valuable stuff. 6618 6619Please see http://www.denx.de/wiki/U-Boot/Patches for details. 6620 6621Patches shall be sent to the u-boot mailing list <u-boot@lists.denx.de>; 6622see http://lists.denx.de/mailman/listinfo/u-boot 6623 6624When you send a patch, please include the following information with 6625it: 6626 6627* For bug fixes: a description of the bug and how your patch fixes 6628 this bug. Please try to include a way of demonstrating that the 6629 patch actually fixes something. 6630 6631* For new features: a description of the feature and your 6632 implementation. 6633 6634* A CHANGELOG entry as plaintext (separate from the patch) 6635 6636* For major contributions, your entry to the CREDITS file 6637 6638* When you add support for a new board, don't forget to add a 6639 maintainer e-mail address to the boards.cfg file, too. 6640 6641* If your patch adds new configuration options, don't forget to 6642 document these in the README file. 6643 6644* The patch itself. If you are using git (which is *strongly* 6645 recommended) you can easily generate the patch using the 6646 "git format-patch". If you then use "git send-email" to send it to 6647 the U-Boot mailing list, you will avoid most of the common problems 6648 with some other mail clients. 6649 6650 If you cannot use git, use "diff -purN OLD NEW". If your version of 6651 diff does not support these options, then get the latest version of 6652 GNU diff. 6653 6654 The current directory when running this command shall be the parent 6655 directory of the U-Boot source tree (i. e. please make sure that 6656 your patch includes sufficient directory information for the 6657 affected files). 6658 6659 We prefer patches as plain text. MIME attachments are discouraged, 6660 and compressed attachments must not be used. 6661 6662* If one logical set of modifications affects or creates several 6663 files, all these changes shall be submitted in a SINGLE patch file. 6664 6665* Changesets that contain different, unrelated modifications shall be 6666 submitted as SEPARATE patches, one patch per changeset. 6667 6668 6669Notes: 6670 6671* Before sending the patch, run the MAKEALL script on your patched 6672 source tree and make sure that no errors or warnings are reported 6673 for any of the boards. 6674 6675* Keep your modifications to the necessary minimum: A patch 6676 containing several unrelated changes or arbitrary reformats will be 6677 returned with a request to re-formatting / split it. 6678 6679* If you modify existing code, make sure that your new code does not 6680 add to the memory footprint of the code ;-) Small is beautiful! 6681 When adding new features, these should compile conditionally only 6682 (using #ifdef), and the resulting code with the new feature 6683 disabled must not need more memory than the old code without your 6684 modification. 6685 6686* Remember that there is a size limit of 100 kB per message on the 6687 u-boot mailing list. Bigger patches will be moderated. If they are 6688 reasonable and not too big, they will be acknowledged. But patches 6689 bigger than the size limit should be avoided. 6690