1Binman Entry Documentation 2=========================== 3 4This file describes the entry types supported by binman. These entry types can 5be placed in an image one by one to build up a final firmware image. It is 6fairly easy to create new entry types. Just add a new file to the 'etype' 7directory. You can use the existing entries as examples. 8 9Note that some entries are subclasses of others, using and extending their 10features to produce new behaviours. 11 12 13 14Entry: blob: Entry containing an arbitrary binary blob 15------------------------------------------------------ 16 17Note: This should not be used by itself. It is normally used as a parent 18class by other entry types. 19 20Properties / Entry arguments: 21 - filename: Filename of file to read into entry 22 - compress: Compression algorithm to use: 23 none: No compression 24 lz4: Use lz4 compression (via 'lz4' command-line utility) 25 26This entry reads data from a file and places it in the entry. The 27default filename is often specified specified by the subclass. See for 28example the 'u_boot' entry which provides the filename 'u-boot.bin'. 29 30If compression is enabled, an extra 'uncomp-size' property is written to 31the node (if enabled with -u) which provides the uncompressed size of the 32data. 33 34 35 36Entry: blob-dtb: A blob that holds a device tree 37------------------------------------------------ 38 39This is a blob containing a device tree. The contents of the blob are 40obtained from the list of available device-tree files, managed by the 41'state' module. 42 43 44 45Entry: blob-named-by-arg: A blob entry which gets its filename property from its subclass 46----------------------------------------------------------------------------------------- 47 48Properties / Entry arguments: 49 - <xxx>-path: Filename containing the contents of this entry (optional, 50 defaults to 0) 51 52where <xxx> is the blob_fname argument to the constructor. 53 54This entry cannot be used directly. Instead, it is used as a parent class 55for another entry, which defined blob_fname. This parameter is used to 56set the entry-arg or property containing the filename. The entry-arg or 57property is in turn used to set the actual filename. 58 59See cros_ec_rw for an example of this. 60 61 62 63Entry: cros-ec-rw: A blob entry which contains a Chromium OS read-write EC image 64-------------------------------------------------------------------------------- 65 66Properties / Entry arguments: 67 - cros-ec-rw-path: Filename containing the EC image 68 69This entry holds a Chromium OS EC (embedded controller) image, for use in 70updating the EC on startup via software sync. 71 72 73 74Entry: files: Entry containing a set of files 75--------------------------------------------- 76 77Properties / Entry arguments: 78 - pattern: Filename pattern to match the files to include 79 - compress: Compression algorithm to use: 80 none: No compression 81 lz4: Use lz4 compression (via 'lz4' command-line utility) 82 83This entry reads a number of files and places each in a separate sub-entry 84within this entry. To access these you need to enable device-tree updates 85at run-time so you can obtain the file positions. 86 87 88 89Entry: fill: An entry which is filled to a particular byte value 90---------------------------------------------------------------- 91 92Properties / Entry arguments: 93 - fill-byte: Byte to use to fill the entry 94 95Note that the size property must be set since otherwise this entry does not 96know how large it should be. 97 98You can often achieve the same effect using the pad-byte property of the 99overall image, in that the space between entries will then be padded with 100that byte. But this entry is sometimes useful for explicitly setting the 101byte value of a region. 102 103 104 105Entry: fmap: An entry which contains an Fmap section 106---------------------------------------------------- 107 108Properties / Entry arguments: 109 None 110 111FMAP is a simple format used by flashrom, an open-source utility for 112reading and writing the SPI flash, typically on x86 CPUs. The format 113provides flashrom with a list of areas, so it knows what it in the flash. 114It can then read or write just a single area, instead of the whole flash. 115 116The format is defined by the flashrom project, in the file lib/fmap.h - 117see www.flashrom.org/Flashrom for more information. 118 119When used, this entry will be populated with an FMAP which reflects the 120entries in the current image. Note that any hierarchy is squashed, since 121FMAP does not support this. 122 123 124 125Entry: gbb: An entry which contains a Chromium OS Google Binary Block 126--------------------------------------------------------------------- 127 128Properties / Entry arguments: 129 - hardware-id: Hardware ID to use for this build (a string) 130 - keydir: Directory containing the public keys to use 131 - bmpblk: Filename containing images used by recovery 132 133Chromium OS uses a GBB to store various pieces of information, in particular 134the root and recovery keys that are used to verify the boot process. Some 135more details are here: 136 137 https://www.chromium.org/chromium-os/firmware-porting-guide/2-concepts 138 139but note that the page dates from 2013 so is quite out of date. See 140README.chromium for how to obtain the required keys and tools. 141 142 143 144Entry: intel-cmc: Entry containing an Intel Chipset Micro Code (CMC) file 145------------------------------------------------------------------------- 146 147Properties / Entry arguments: 148 - filename: Filename of file to read into entry 149 150This file contains microcode for some devices in a special format. An 151example filename is 'Microcode/C0_22211.BIN'. 152 153See README.x86 for information about x86 binary blobs. 154 155 156 157Entry: intel-descriptor: Intel flash descriptor block (4KB) 158----------------------------------------------------------- 159 160Properties / Entry arguments: 161 filename: Filename of file containing the descriptor. This is typically 162 a 4KB binary file, sometimes called 'descriptor.bin' 163 164This entry is placed at the start of flash and provides information about 165the SPI flash regions. In particular it provides the base address and 166size of the ME (Management Engine) region, allowing us to place the ME 167binary in the right place. 168 169With this entry in your image, the position of the 'intel-me' entry will be 170fixed in the image, which avoids you needed to specify an offset for that 171region. This is useful, because it is not possible to change the position 172of the ME region without updating the descriptor. 173 174See README.x86 for information about x86 binary blobs. 175 176 177 178Entry: intel-fsp: Entry containing an Intel Firmware Support Package (FSP) file 179------------------------------------------------------------------------------- 180 181Properties / Entry arguments: 182 - filename: Filename of file to read into entry 183 184This file contains binary blobs which are used on some devices to make the 185platform work. U-Boot executes this code since it is not possible to set up 186the hardware using U-Boot open-source code. Documentation is typically not 187available in sufficient detail to allow this. 188 189An example filename is 'FSP/QUEENSBAY_FSP_GOLD_001_20-DECEMBER-2013.fd' 190 191See README.x86 for information about x86 binary blobs. 192 193 194 195Entry: intel-me: Entry containing an Intel Management Engine (ME) file 196---------------------------------------------------------------------- 197 198Properties / Entry arguments: 199 - filename: Filename of file to read into entry 200 201This file contains code used by the SoC that is required to make it work. 202The Management Engine is like a background task that runs things that are 203not clearly documented, but may include keyboard, deplay and network 204access. For platform that use ME it is not possible to disable it. U-Boot 205does not directly execute code in the ME binary. 206 207A typical filename is 'me.bin'. 208 209See README.x86 for information about x86 binary blobs. 210 211 212 213Entry: intel-mrc: Entry containing an Intel Memory Reference Code (MRC) file 214---------------------------------------------------------------------------- 215 216Properties / Entry arguments: 217 - filename: Filename of file to read into entry 218 219This file contains code for setting up the SDRAM on some Intel systems. This 220is executed by U-Boot when needed early during startup. A typical filename 221is 'mrc.bin'. 222 223See README.x86 for information about x86 binary blobs. 224 225 226 227Entry: intel-vbt: Entry containing an Intel Video BIOS Table (VBT) file 228----------------------------------------------------------------------- 229 230Properties / Entry arguments: 231 - filename: Filename of file to read into entry 232 233This file contains code that sets up the integrated graphics subsystem on 234some Intel SoCs. U-Boot executes this when the display is started up. 235 236See README.x86 for information about Intel binary blobs. 237 238 239 240Entry: intel-vga: Entry containing an Intel Video Graphics Adaptor (VGA) file 241----------------------------------------------------------------------------- 242 243Properties / Entry arguments: 244 - filename: Filename of file to read into entry 245 246This file contains code that sets up the integrated graphics subsystem on 247some Intel SoCs. U-Boot executes this when the display is started up. 248 249This is similar to the VBT file but in a different format. 250 251See README.x86 for information about Intel binary blobs. 252 253 254 255Entry: powerpc-mpc85xx-bootpg-resetvec: PowerPC mpc85xx bootpg + resetvec code for U-Boot 256----------------------------------------------------------------------------------------- 257 258Properties / Entry arguments: 259 - filename: Filename of u-boot-br.bin (default 'u-boot-br.bin') 260 261This enrty is valid for PowerPC mpc85xx cpus. This entry holds 262'bootpg + resetvec' code for PowerPC mpc85xx CPUs which needs to be 263placed at offset 'RESET_VECTOR_ADDRESS - 0xffc'. 264 265 266 267Entry: section: Entry that contains other entries 268------------------------------------------------- 269 270Properties / Entry arguments: (see binman README for more information) 271 - size: Size of section in bytes 272 - align-size: Align size to a particular power of two 273 - pad-before: Add padding before the entry 274 - pad-after: Add padding after the entry 275 - pad-byte: Pad byte to use when padding 276 - sort-by-offset: Reorder the entries by offset 277 - end-at-4gb: Used to build an x86 ROM which ends at 4GB (2^32) 278 - name-prefix: Adds a prefix to the name of every entry in the section 279 when writing out the map 280 281A section is an entry which can contain other entries, thus allowing 282hierarchical images to be created. See 'Sections and hierarchical images' 283in the binman README for more information. 284 285 286 287Entry: text: An entry which contains text 288----------------------------------------- 289 290The text can be provided either in the node itself or by a command-line 291argument. There is a level of indirection to allow multiple text strings 292and sharing of text. 293 294Properties / Entry arguments: 295 text-label: The value of this string indicates the property / entry-arg 296 that contains the string to place in the entry 297 <xxx> (actual name is the value of text-label): contains the string to 298 place in the entry. 299 300Example node: 301 302 text { 303 size = <50>; 304 text-label = "message"; 305 }; 306 307You can then use: 308 309 binman -amessage="this is my message" 310 311and binman will insert that string into the entry. 312 313It is also possible to put the string directly in the node: 314 315 text { 316 size = <8>; 317 text-label = "message"; 318 message = "a message directly in the node" 319 }; 320 321The text is not itself nul-terminated. This can be achieved, if required, 322by setting the size of the entry to something larger than the text. 323 324 325 326Entry: u-boot: U-Boot flat binary 327--------------------------------- 328 329Properties / Entry arguments: 330 - filename: Filename of u-boot.bin (default 'u-boot.bin') 331 332This is the U-Boot binary, containing relocation information to allow it 333to relocate itself at runtime. The binary typically includes a device tree 334blob at the end of it. Use u_boot_nodtb if you want to package the device 335tree separately. 336 337U-Boot can access binman symbols at runtime. See: 338 339 'Access to binman entry offsets at run time (fdt)' 340 341in the binman README for more information. 342 343 344 345Entry: u-boot-dtb: U-Boot device tree 346------------------------------------- 347 348Properties / Entry arguments: 349 - filename: Filename of u-boot.dtb (default 'u-boot.dtb') 350 351This is the U-Boot device tree, containing configuration information for 352U-Boot. U-Boot needs this to know what devices are present and which drivers 353to activate. 354 355Note: This is mostly an internal entry type, used by others. This allows 356binman to know which entries contain a device tree. 357 358 359 360Entry: u-boot-dtb-with-ucode: A U-Boot device tree file, with the microcode removed 361----------------------------------------------------------------------------------- 362 363Properties / Entry arguments: 364 - filename: Filename of u-boot.dtb (default 'u-boot.dtb') 365 366See Entry_u_boot_ucode for full details of the three entries involved in 367this process. This entry provides the U-Boot device-tree file, which 368contains the microcode. If the microcode is not being collated into one 369place then the offset and size of the microcode is recorded by this entry, 370for use by u_boot_with_ucode_ptr. If it is being collated, then this 371entry deletes the microcode from the device tree (to save space) and makes 372it available to u_boot_ucode. 373 374 375 376Entry: u-boot-elf: U-Boot ELF image 377----------------------------------- 378 379Properties / Entry arguments: 380 - filename: Filename of u-boot (default 'u-boot') 381 382This is the U-Boot ELF image. It does not include a device tree but can be 383relocated to any address for execution. 384 385 386 387Entry: u-boot-img: U-Boot legacy image 388-------------------------------------- 389 390Properties / Entry arguments: 391 - filename: Filename of u-boot.img (default 'u-boot.img') 392 393This is the U-Boot binary as a packaged image, in legacy format. It has a 394header which allows it to be loaded at the correct address for execution. 395 396You should use FIT (Flat Image Tree) instead of the legacy image for new 397applications. 398 399 400 401Entry: u-boot-nodtb: U-Boot flat binary without device tree appended 402-------------------------------------------------------------------- 403 404Properties / Entry arguments: 405 - filename: Filename of u-boot.bin (default 'u-boot-nodtb.bin') 406 407This is the U-Boot binary, containing relocation information to allow it 408to relocate itself at runtime. It does not include a device tree blob at 409the end of it so normally cannot work without it. You can add a u_boot_dtb 410entry after this one, or use a u_boot entry instead (which contains both 411U-Boot and the device tree). 412 413 414 415Entry: u-boot-spl: U-Boot SPL binary 416------------------------------------ 417 418Properties / Entry arguments: 419 - filename: Filename of u-boot-spl.bin (default 'spl/u-boot-spl.bin') 420 421This is the U-Boot SPL (Secondary Program Loader) binary. This is a small 422binary which loads before U-Boot proper, typically into on-chip SRAM. It is 423responsible for locating, loading and jumping to U-Boot. Note that SPL is 424not relocatable so must be loaded to the correct address in SRAM, or written 425to run from the correct address if direct flash execution is possible (e.g. 426on x86 devices). 427 428SPL can access binman symbols at runtime. See: 429 430 'Access to binman entry offsets at run time (symbols)' 431 432in the binman README for more information. 433 434The ELF file 'spl/u-boot-spl' must also be available for this to work, since 435binman uses that to look up symbols to write into the SPL binary. 436 437 438 439Entry: u-boot-spl-bss-pad: U-Boot SPL binary padded with a BSS region 440--------------------------------------------------------------------- 441 442Properties / Entry arguments: 443 None 444 445This is similar to u_boot_spl except that padding is added after the SPL 446binary to cover the BSS (Block Started by Symbol) region. This region holds 447the various used by SPL. It is set to 0 by SPL when it starts up. If you 448want to append data to the SPL image (such as a device tree file), you must 449pad out the BSS region to avoid the data overlapping with U-Boot variables. 450This entry is useful in that case. It automatically pads out the entry size 451to cover both the code, data and BSS. 452 453The ELF file 'spl/u-boot-spl' must also be available for this to work, since 454binman uses that to look up the BSS address. 455 456 457 458Entry: u-boot-spl-dtb: U-Boot SPL device tree 459--------------------------------------------- 460 461Properties / Entry arguments: 462 - filename: Filename of u-boot.dtb (default 'spl/u-boot-spl.dtb') 463 464This is the SPL device tree, containing configuration information for 465SPL. SPL needs this to know what devices are present and which drivers 466to activate. 467 468 469 470Entry: u-boot-spl-elf: U-Boot SPL ELF image 471------------------------------------------- 472 473Properties / Entry arguments: 474 - filename: Filename of SPL u-boot (default 'spl/u-boot') 475 476This is the U-Boot SPL ELF image. It does not include a device tree but can 477be relocated to any address for execution. 478 479 480 481Entry: u-boot-spl-nodtb: SPL binary without device tree appended 482---------------------------------------------------------------- 483 484Properties / Entry arguments: 485 - filename: Filename of spl/u-boot-spl-nodtb.bin (default 486 'spl/u-boot-spl-nodtb.bin') 487 488This is the U-Boot SPL binary, It does not include a device tree blob at 489the end of it so may not be able to work without it, assuming SPL needs 490a device tree to operation on your platform. You can add a u_boot_spl_dtb 491entry after this one, or use a u_boot_spl entry instead (which contains 492both SPL and the device tree). 493 494 495 496Entry: u-boot-spl-with-ucode-ptr: U-Boot SPL with embedded microcode pointer 497---------------------------------------------------------------------------- 498 499This is used when SPL must set up the microcode for U-Boot. 500 501See Entry_u_boot_ucode for full details of the entries involved in this 502process. 503 504 505 506Entry: u-boot-tpl: U-Boot TPL binary 507------------------------------------ 508 509Properties / Entry arguments: 510 - filename: Filename of u-boot-tpl.bin (default 'tpl/u-boot-tpl.bin') 511 512This is the U-Boot TPL (Tertiary Program Loader) binary. This is a small 513binary which loads before SPL, typically into on-chip SRAM. It is 514responsible for locating, loading and jumping to SPL, the next-stage 515loader. Note that SPL is not relocatable so must be loaded to the correct 516address in SRAM, or written to run from the correct address if direct 517flash execution is possible (e.g. on x86 devices). 518 519SPL can access binman symbols at runtime. See: 520 521 'Access to binman entry offsets at run time (symbols)' 522 523in the binman README for more information. 524 525The ELF file 'tpl/u-boot-tpl' must also be available for this to work, since 526binman uses that to look up symbols to write into the TPL binary. 527 528 529 530Entry: u-boot-tpl-dtb: U-Boot TPL device tree 531--------------------------------------------- 532 533Properties / Entry arguments: 534 - filename: Filename of u-boot.dtb (default 'tpl/u-boot-tpl.dtb') 535 536This is the TPL device tree, containing configuration information for 537TPL. TPL needs this to know what devices are present and which drivers 538to activate. 539 540 541 542Entry: u-boot-tpl-dtb-with-ucode: U-Boot TPL with embedded microcode pointer 543---------------------------------------------------------------------------- 544 545This is used when TPL must set up the microcode for U-Boot. 546 547See Entry_u_boot_ucode for full details of the entries involved in this 548process. 549 550 551 552Entry: u-boot-tpl-with-ucode-ptr: U-Boot TPL with embedded microcode pointer 553---------------------------------------------------------------------------- 554 555See Entry_u_boot_ucode for full details of the entries involved in this 556process. 557 558 559 560Entry: u-boot-ucode: U-Boot microcode block 561------------------------------------------- 562 563Properties / Entry arguments: 564 None 565 566The contents of this entry are filled in automatically by other entries 567which must also be in the image. 568 569U-Boot on x86 needs a single block of microcode. This is collected from 570the various microcode update nodes in the device tree. It is also unable 571to read the microcode from the device tree on platforms that use FSP 572(Firmware Support Package) binaries, because the API requires that the 573microcode is supplied before there is any SRAM available to use (i.e. 574the FSP sets up the SRAM / cache-as-RAM but does so in the call that 575requires the microcode!). To keep things simple, all x86 platforms handle 576microcode the same way in U-Boot (even non-FSP platforms). This is that 577a table is placed at _dt_ucode_base_size containing the base address and 578size of the microcode. This is either passed to the FSP (for FSP 579platforms), or used to set up the microcode (for non-FSP platforms). 580This all happens in the build system since it is the only way to get 581the microcode into a single blob and accessible without SRAM. 582 583There are two cases to handle. If there is only one microcode blob in 584the device tree, then the ucode pointer it set to point to that. This 585entry (u-boot-ucode) is empty. If there is more than one update, then 586this entry holds the concatenation of all updates, and the device tree 587entry (u-boot-dtb-with-ucode) is updated to remove the microcode. This 588last step ensures that that the microcode appears in one contiguous 589block in the image and is not unnecessarily duplicated in the device 590tree. It is referred to as 'collation' here. 591 592Entry types that have a part to play in handling microcode: 593 594 Entry_u_boot_with_ucode_ptr: 595 Contains u-boot-nodtb.bin (i.e. U-Boot without the device tree). 596 It updates it with the address and size of the microcode so that 597 U-Boot can find it early on start-up. 598 Entry_u_boot_dtb_with_ucode: 599 Contains u-boot.dtb. It stores the microcode in a 600 'self.ucode_data' property, which is then read by this class to 601 obtain the microcode if needed. If collation is performed, it 602 removes the microcode from the device tree. 603 Entry_u_boot_ucode: 604 This class. If collation is enabled it reads the microcode from 605 the Entry_u_boot_dtb_with_ucode entry, and uses it as the 606 contents of this entry. 607 608 609 610Entry: u-boot-with-ucode-ptr: U-Boot with embedded microcode pointer 611-------------------------------------------------------------------- 612 613Properties / Entry arguments: 614 - filename: Filename of u-boot-nodtb.dtb (default 'u-boot-nodtb.dtb') 615 - optional-ucode: boolean property to make microcode optional. If the 616 u-boot.bin image does not include microcode, no error will 617 be generated. 618 619See Entry_u_boot_ucode for full details of the three entries involved in 620this process. This entry updates U-Boot with the offset and size of the 621microcode, to allow early x86 boot code to find it without doing anything 622complicated. Otherwise it is the same as the u_boot entry. 623 624 625 626Entry: vblock: An entry which contains a Chromium OS verified boot block 627------------------------------------------------------------------------ 628 629Properties / Entry arguments: 630 - keydir: Directory containing the public keys to use 631 - keyblock: Name of the key file to use (inside keydir) 632 - signprivate: Name of provide key file to use (inside keydir) 633 - version: Version number of the vblock (typically 1) 634 - kernelkey: Name of the kernel key to use (inside keydir) 635 - preamble-flags: Value of the vboot preamble flags (typically 0) 636 637Output files: 638 - input.<unique_name> - input file passed to futility 639 - vblock.<unique_name> - output file generated by futility (which is 640 used as the entry contents) 641 642Chromium OS signs the read-write firmware and kernel, writing the signature 643in this block. This allows U-Boot to verify that the next firmware stage 644and kernel are genuine. 645 646 647 648Entry: x86-start16: x86 16-bit start-up code for U-Boot 649------------------------------------------------------- 650 651Properties / Entry arguments: 652 - filename: Filename of u-boot-x86-16bit.bin (default 653 'u-boot-x86-16bit.bin') 654 655x86 CPUs start up in 16-bit mode, even if they are 32-bit CPUs. This code 656must be placed at a particular address. This entry holds that code. It is 657typically placed at offset CONFIG_SYS_X86_START16. The code is responsible 658for changing to 32-bit mode and jumping to U-Boot's entry point, which 659requires 32-bit mode (for 32-bit U-Boot). 660 661For 64-bit U-Boot, the 'x86_start16_spl' entry type is used instead. 662 663 664 665Entry: x86-start16-spl: x86 16-bit start-up code for SPL 666-------------------------------------------------------- 667 668Properties / Entry arguments: 669 - filename: Filename of spl/u-boot-x86-16bit-spl.bin (default 670 'spl/u-boot-x86-16bit-spl.bin') 671 672x86 CPUs start up in 16-bit mode, even if they are 64-bit CPUs. This code 673must be placed at a particular address. This entry holds that code. It is 674typically placed at offset CONFIG_SYS_X86_START16. The code is responsible 675for changing to 32-bit mode and starting SPL, which in turn changes to 67664-bit mode and jumps to U-Boot (for 64-bit U-Boot). 677 678For 32-bit U-Boot, the 'x86_start16' entry type is used instead. 679 680 681 682Entry: x86-start16-tpl: x86 16-bit start-up code for TPL 683-------------------------------------------------------- 684 685Properties / Entry arguments: 686 - filename: Filename of tpl/u-boot-x86-16bit-tpl.bin (default 687 'tpl/u-boot-x86-16bit-tpl.bin') 688 689x86 CPUs start up in 16-bit mode, even if they are 64-bit CPUs. This code 690must be placed at a particular address. This entry holds that code. It is 691typically placed at offset CONFIG_SYS_X86_START16. The code is responsible 692for changing to 32-bit mode and starting TPL, which in turn jumps to SPL. 693 694If TPL is not being used, the 'x86_start16_spl or 'x86_start16' entry types 695may be used instead. 696 697 698 699