1 Binman Entry Documentation
2 ===========================
4 This file describes the entry types supported by binman. These entry types can
5 be placed in an image one by one to build up a final firmware image. It is
6 fairly easy to create new entry types. Just add a new file to the 'etype'
7 directory. You can use the existing entries as examples.
9 Note that some entries are subclasses of others, using and extending their
10 features to produce new behaviours.
14 Entry: atf-bl31: Entry containing an ARM Trusted Firmware (ATF) BL31 blob
15 -------------------------------------------------------------------------
17 Properties / Entry arguments:
18 - atf-bl31-path: Filename of file to read into entry. This is typically
19 called bl31.bin or bl31.elf
21 This entry holds the run-time firmware, typically started by U-Boot SPL.
22 See the U-Boot README for your architecture or board for how to use it. See
23 https://github.com/ARM-software/arm-trusted-firmware for more information
28 Entry: blob: Entry containing an arbitrary binary blob
29 ------------------------------------------------------
31 Note: This should not be used by itself. It is normally used as a parent
32 class by other entry types.
34 Properties / Entry arguments:
35 - filename: Filename of file to read into entry
36 - compress: Compression algorithm to use:
38 lz4: Use lz4 compression (via 'lz4' command-line utility)
40 This entry reads data from a file and places it in the entry. The
41 default filename is often specified specified by the subclass. See for
42 example the 'u_boot' entry which provides the filename 'u-boot.bin'.
44 If compression is enabled, an extra 'uncomp-size' property is written to
45 the node (if enabled with -u) which provides the uncompressed size of the
50 Entry: blob-dtb: A blob that holds a device tree
51 ------------------------------------------------
53 This is a blob containing a device tree. The contents of the blob are
54 obtained from the list of available device-tree files, managed by the
59 Entry: blob-ext: Entry containing an externally built binary blob
60 -----------------------------------------------------------------
62 Note: This should not be used by itself. It is normally used as a parent
63 class by other entry types.
65 If the file providing this blob is missing, binman can optionally ignore it
66 and produce a broken image with a warning.
68 See 'blob' for Properties / Entry arguments.
72 Entry: blob-named-by-arg: A blob entry which gets its filename property from its subclass
73 -----------------------------------------------------------------------------------------
75 Properties / Entry arguments:
76 - <xxx>-path: Filename containing the contents of this entry (optional,
79 where <xxx> is the blob_fname argument to the constructor.
81 This entry cannot be used directly. Instead, it is used as a parent class
82 for another entry, which defined blob_fname. This parameter is used to
83 set the entry-arg or property containing the filename. The entry-arg or
84 property is in turn used to set the actual filename.
86 See cros_ec_rw for an example of this.
90 Entry: cbfs: Entry containing a Coreboot Filesystem (CBFS)
91 ----------------------------------------------------------
93 A CBFS provides a way to group files into a group. It has a simple directory
94 structure and allows the position of individual files to be set, since it is
95 designed to support execute-in-place in an x86 SPI-flash device. Where XIP
96 is not used, it supports compression and storing ELF files.
98 CBFS is used by coreboot as its way of orgnanising SPI-flash contents.
100 The contents of the CBFS are defined by subnodes of the cbfs entry, e.g.:
112 This creates a CBFS 1MB in size two files in it: u-boot.bin and u-boot.dtb.
113 Note that the size is required since binman does not support calculating it.
114 The contents of each entry is just what binman would normally provide if it
115 were not a CBFS node. A blob type can be used to import arbitrary files as
116 with the second subnode below:
127 filename = "u-boot.dtb";
129 cbfs-compress = "lz4";
130 cbfs-offset = <0x100000>;
134 This creates a CBFS 1MB in size with u-boot.bin (named "BOOT") and
135 u-boot.dtb (named "dtb") and compressed with the lz4 algorithm.
138 Properties supported in the top-level CBFS node:
141 Defaults to "x86", but you can specify the architecture if needed.
144 Properties supported in the CBFS entry subnodes:
147 This is the name of the file created in CBFS. It defaults to the entry
148 name (which is the node name), but you can override it with this
152 This is the CBFS file type. The following are supported:
155 This is a 'raw' file, although compression is supported. It can be
156 used to store any file in CBFS.
159 This is an ELF file that has been loaded (i.e. mapped to memory), so
160 appears in the CBFS as a flat binary. The input file must be an ELF
161 image, for example this puts "u-boot" (the ELF image) into a 'stage'
172 You can use your own ELF file with something like:
178 filename = "cbfs-stage.elf";
183 As mentioned, the file is converted to a flat binary, so it is
184 equivalent to adding "u-boot.bin", for example, but with the load and
185 start addresses specified by the ELF. At present there is no option
186 to add a flat binary with a load/start address, similar to the
187 'add-flat-binary' option in cbfstool.
190 This is the offset of the file's data within the CBFS. It is used to
191 specify where the file should be placed in cases where a fixed position
192 is needed. Typical uses are for code which is not relocatable and must
193 execute in-place from a particular address. This works because SPI flash
194 is generally mapped into memory on x86 devices. The file header is
195 placed before this offset so that the data start lines up exactly with
196 the chosen offset. If this property is not provided, then the file is
197 placed in the next available spot.
199 The current implementation supports only a subset of CBFS features. It does
200 not support other file types (e.g. payload), adding multiple files (like the
201 'files' entry with a pattern supported by binman), putting files at a
202 particular offset in the CBFS and a few other things.
204 Of course binman can create images containing multiple CBFSs, simply by
205 defining these in the binman config:
232 filename = "image.jpg";
237 This creates an 8MB image with two CBFSs, one at offset 1MB, one at 7MB,
242 Entry: cros-ec-rw: A blob entry which contains a Chromium OS read-write EC image
243 --------------------------------------------------------------------------------
245 Properties / Entry arguments:
246 - cros-ec-rw-path: Filename containing the EC image
248 This entry holds a Chromium OS EC (embedded controller) image, for use in
249 updating the EC on startup via software sync.
253 Entry: fdtmap: An entry which contains an FDT map
254 -------------------------------------------------
256 Properties / Entry arguments:
259 An FDT map is just a header followed by an FDT containing a list of all the
260 entries in the image. The root node corresponds to the image node in the
261 original FDT, and an image-name property indicates the image name in that
264 The header is the string _FDTMAP_ followed by 8 unused bytes.
266 When used, this entry will be populated with an FDT map which reflects the
267 entries in the current image. Hierarchy is preserved, and all offsets and
270 Note that the -u option must be provided to ensure that binman updates the
271 FDT with the position of each entry.
273 Example output for a simple image with U-Boot and an FDT map:
276 image-name = "binman";
278 image-pos = <0x00000000>;
279 offset = <0x00000000>;
282 image-pos = <0x00000000>;
283 offset = <0x00000000>;
287 image-pos = <0x00000004>;
288 offset = <0x00000004>;
292 If allow-repack is used then 'orig-offset' and 'orig-size' properties are
293 added as necessary. See the binman README.
297 Entry: files: Entry containing a set of files
298 ---------------------------------------------
300 Properties / Entry arguments:
301 - pattern: Filename pattern to match the files to include
302 - compress: Compression algorithm to use:
304 lz4: Use lz4 compression (via 'lz4' command-line utility)
306 This entry reads a number of files and places each in a separate sub-entry
307 within this entry. To access these you need to enable device-tree updates
308 at run-time so you can obtain the file positions.
312 Entry: fill: An entry which is filled to a particular byte value
313 ----------------------------------------------------------------
315 Properties / Entry arguments:
316 - fill-byte: Byte to use to fill the entry
318 Note that the size property must be set since otherwise this entry does not
319 know how large it should be.
321 You can often achieve the same effect using the pad-byte property of the
322 overall image, in that the space between entries will then be padded with
323 that byte. But this entry is sometimes useful for explicitly setting the
324 byte value of a region.
328 Entry: fit: Entry containing a FIT
329 ----------------------------------
331 This calls mkimage to create a FIT (U-Boot Flat Image Tree) based on the
334 Nodes for the FIT should be written out in the binman configuration just as
335 they would be in a file passed to mkimage.
337 For example, this creates an image containing a FIT with U-Boot SPL:
341 description = "Test FIT";
342 fit,fdt-list = "of-list";
350 compression = "none";
361 U-Boot supports creating fdt and config nodes automatically. To do this,
362 pass an of-list property (e.g. -a of-list=file1 file2). This tells binman
363 that you want to generates nodes for two files: file1.dtb and file2.dtb
364 The fit,fdt-list property (see above) indicates that of-list should be used.
365 If the property is missing you will get an error.
367 Then add a 'generator node', a node with a name starting with '@':
371 description = "fdt-NAME";
373 compression = "none";
377 This tells binman to create nodes fdt-1 and fdt-2 for each of your two
378 files. All the properties you specify will be included in the node. This
379 node acts like a template to generate the nodes. The generator node itself
380 does not appear in the output - it is replaced with what binman generates.
382 You can create config nodes in a similar way:
385 default = "@config-DEFAULT-SEQ";
387 description = "NAME";
394 This tells binman to create nodes config-1 and config-2, i.e. a config for
395 each of your two files.
397 Available substitutions for '@' nodes are:
399 SEQ Sequence number of the generated fdt (1, 2, ...)
400 NAME Name of the dtb as provided (i.e. without adding '.dtb')
402 Note that if no devicetree files are provided (with '-a of-list' as above)
403 then no nodes will be generated.
405 The 'default' property, if present, will be automatically set to the name
406 if of configuration whose devicetree matches the 'default-dt' entry
407 argument, e.g. with '-a default-dt=sun50i-a64-pine64-lts'.
410 Properties (in the 'fit' node itself):
411 fit,external-offset: Indicates that the contents of the FIT are external
412 and provides the external offset. This is passsed to mkimage via
418 Entry: fmap: An entry which contains an Fmap section
419 ----------------------------------------------------
421 Properties / Entry arguments:
424 FMAP is a simple format used by flashrom, an open-source utility for
425 reading and writing the SPI flash, typically on x86 CPUs. The format
426 provides flashrom with a list of areas, so it knows what it in the flash.
427 It can then read or write just a single area, instead of the whole flash.
429 The format is defined by the flashrom project, in the file lib/fmap.h -
430 see www.flashrom.org/Flashrom for more information.
432 When used, this entry will be populated with an FMAP which reflects the
433 entries in the current image. Note that any hierarchy is squashed, since
434 FMAP does not support this. Also, CBFS entries appear as a single entry -
435 the sub-entries are ignored.
439 Entry: gbb: An entry which contains a Chromium OS Google Binary Block
440 ---------------------------------------------------------------------
442 Properties / Entry arguments:
443 - hardware-id: Hardware ID to use for this build (a string)
444 - keydir: Directory containing the public keys to use
445 - bmpblk: Filename containing images used by recovery
447 Chromium OS uses a GBB to store various pieces of information, in particular
448 the root and recovery keys that are used to verify the boot process. Some
449 more details are here:
451 https://www.chromium.org/chromium-os/firmware-porting-guide/2-concepts
453 but note that the page dates from 2013 so is quite out of date. See
454 README.chromium for how to obtain the required keys and tools.
458 Entry: image-header: An entry which contains a pointer to the FDT map
459 ---------------------------------------------------------------------
461 Properties / Entry arguments:
462 location: Location of header ("start" or "end" of image). This is
463 optional. If omitted then the entry must have an offset property.
465 This adds an 8-byte entry to the start or end of the image, pointing to the
466 location of the FDT map. The format is a magic number followed by an offset
467 from the start or end of the image, in twos-compliment format.
469 This entry must be in the top-level part of the image.
471 NOTE: If the location is at the start/end, you will probably need to specify
472 sort-by-offset for the image, unless you actually put the image header
473 first/last in the entry list.
477 Entry: intel-cmc: Entry containing an Intel Chipset Micro Code (CMC) file
478 -------------------------------------------------------------------------
480 Properties / Entry arguments:
481 - filename: Filename of file to read into entry
483 This file contains microcode for some devices in a special format. An
484 example filename is 'Microcode/C0_22211.BIN'.
486 See README.x86 for information about x86 binary blobs.
490 Entry: intel-descriptor: Intel flash descriptor block (4KB)
491 -----------------------------------------------------------
493 Properties / Entry arguments:
494 filename: Filename of file containing the descriptor. This is typically
495 a 4KB binary file, sometimes called 'descriptor.bin'
497 This entry is placed at the start of flash and provides information about
498 the SPI flash regions. In particular it provides the base address and
499 size of the ME (Management Engine) region, allowing us to place the ME
500 binary in the right place.
502 With this entry in your image, the position of the 'intel-me' entry will be
503 fixed in the image, which avoids you needed to specify an offset for that
504 region. This is useful, because it is not possible to change the position
505 of the ME region without updating the descriptor.
507 See README.x86 for information about x86 binary blobs.
511 Entry: intel-fit: Intel Firmware Image Table (FIT)
512 --------------------------------------------------
514 This entry contains a dummy FIT as required by recent Intel CPUs. The FIT
515 contains information about the firmware and microcode available in the
518 At present binman only supports a basic FIT with no microcode.
522 Entry: intel-fit-ptr: Intel Firmware Image Table (FIT) pointer
523 --------------------------------------------------------------
525 This entry contains a pointer to the FIT. It is required to be at address
526 0xffffffc0 in the image.
530 Entry: intel-fsp: Entry containing an Intel Firmware Support Package (FSP) file
531 -------------------------------------------------------------------------------
533 Properties / Entry arguments:
534 - filename: Filename of file to read into entry
536 This file contains binary blobs which are used on some devices to make the
537 platform work. U-Boot executes this code since it is not possible to set up
538 the hardware using U-Boot open-source code. Documentation is typically not
539 available in sufficient detail to allow this.
541 An example filename is 'FSP/QUEENSBAY_FSP_GOLD_001_20-DECEMBER-2013.fd'
543 See README.x86 for information about x86 binary blobs.
547 Entry: intel-fsp-m: Entry containing Intel Firmware Support Package (FSP) memory init
548 -------------------------------------------------------------------------------------
550 Properties / Entry arguments:
551 - filename: Filename of file to read into entry
553 This file contains a binary blob which is used on some devices to set up
554 SDRAM. U-Boot executes this code in SPL so that it can make full use of
555 memory. Documentation is typically not available in sufficient detail to
556 allow U-Boot do this this itself..
558 An example filename is 'fsp_m.bin'
560 See README.x86 for information about x86 binary blobs.
564 Entry: intel-fsp-s: Entry containing Intel Firmware Support Package (FSP) silicon init
565 --------------------------------------------------------------------------------------
567 Properties / Entry arguments:
568 - filename: Filename of file to read into entry
570 This file contains a binary blob which is used on some devices to set up
571 the silicon. U-Boot executes this code in U-Boot proper after SDRAM is
572 running, so that it can make full use of memory. Documentation is typically
573 not available in sufficient detail to allow U-Boot do this this itself.
575 An example filename is 'fsp_s.bin'
577 See README.x86 for information about x86 binary blobs.
581 Entry: intel-fsp-t: Entry containing Intel Firmware Support Package (FSP) temp ram init
582 ---------------------------------------------------------------------------------------
584 Properties / Entry arguments:
585 - filename: Filename of file to read into entry
587 This file contains a binary blob which is used on some devices to set up
588 temporary memory (Cache-as-RAM or CAR). U-Boot executes this code in TPL so
589 that it has access to memory for its stack and initial storage.
591 An example filename is 'fsp_t.bin'
593 See README.x86 for information about x86 binary blobs.
597 Entry: intel-ifwi: Entry containing an Intel Integrated Firmware Image (IFWI) file
598 ----------------------------------------------------------------------------------
600 Properties / Entry arguments:
601 - filename: Filename of file to read into entry. This is either the
602 IFWI file itself, or a file that can be converted into one using a
604 - convert-fit: If present this indicates that the ifwitool should be
605 used to convert the provided file into a IFWI.
607 This file contains code and data used by the SoC that is required to make
608 it work. It includes U-Boot TPL, microcode, things related to the CSE
609 (Converged Security Engine, the microcontroller that loads all the firmware)
610 and other items beyond the wit of man.
612 A typical filename is 'ifwi.bin' for an IFWI file, or 'fitimage.bin' for a
613 file that will be converted to an IFWI.
615 The position of this entry is generally set by the intel-descriptor entry.
617 The contents of the IFWI are specified by the subnodes of the IFWI node.
618 Each subnode describes an entry which is placed into the IFWFI with a given
619 sub-partition (and optional entry name).
621 Properties for subnodes:
622 ifwi-subpart - sub-parition to put this entry into, e.g. "IBBP"
623 ifwi-entry - entry name t use, e.g. "IBBL"
624 ifwi-replace - if present, indicates that the item should be replaced
625 in the IFWI. Otherwise it is added.
627 See README.x86 for information about x86 binary blobs.
631 Entry: intel-me: Entry containing an Intel Management Engine (ME) file
632 ----------------------------------------------------------------------
634 Properties / Entry arguments:
635 - filename: Filename of file to read into entry
637 This file contains code used by the SoC that is required to make it work.
638 The Management Engine is like a background task that runs things that are
639 not clearly documented, but may include keyboard, display and network
640 access. For platform that use ME it is not possible to disable it. U-Boot
641 does not directly execute code in the ME binary.
643 A typical filename is 'me.bin'.
645 The position of this entry is generally set by the intel-descriptor entry.
647 See README.x86 for information about x86 binary blobs.
651 Entry: intel-mrc: Entry containing an Intel Memory Reference Code (MRC) file
652 ----------------------------------------------------------------------------
654 Properties / Entry arguments:
655 - filename: Filename of file to read into entry
657 This file contains code for setting up the SDRAM on some Intel systems. This
658 is executed by U-Boot when needed early during startup. A typical filename
661 See README.x86 for information about x86 binary blobs.
665 Entry: intel-refcode: Entry containing an Intel Reference Code file
666 -------------------------------------------------------------------
668 Properties / Entry arguments:
669 - filename: Filename of file to read into entry
671 This file contains code for setting up the platform on some Intel systems.
672 This is executed by U-Boot when needed early during startup. A typical
673 filename is 'refcode.bin'.
675 See README.x86 for information about x86 binary blobs.
679 Entry: intel-vbt: Entry containing an Intel Video BIOS Table (VBT) file
680 -----------------------------------------------------------------------
682 Properties / Entry arguments:
683 - filename: Filename of file to read into entry
685 This file contains code that sets up the integrated graphics subsystem on
686 some Intel SoCs. U-Boot executes this when the display is started up.
688 See README.x86 for information about Intel binary blobs.
692 Entry: intel-vga: Entry containing an Intel Video Graphics Adaptor (VGA) file
693 -----------------------------------------------------------------------------
695 Properties / Entry arguments:
696 - filename: Filename of file to read into entry
698 This file contains code that sets up the integrated graphics subsystem on
699 some Intel SoCs. U-Boot executes this when the display is started up.
701 This is similar to the VBT file but in a different format.
703 See README.x86 for information about Intel binary blobs.
707 Entry: mkimage: Entry containing a binary produced by mkimage
708 -------------------------------------------------------------
710 Properties / Entry arguments:
711 - datafile: Filename for -d argument
712 - args: Other arguments to pass
714 The data passed to mkimage is collected from subnodes of the mkimage node,
718 args = "-n test -T imximage";
724 This calls mkimage to create an imximage with u-boot-spl.bin as the input
725 file. The output from mkimage then becomes part of the image produced by
730 Entry: powerpc-mpc85xx-bootpg-resetvec: PowerPC mpc85xx bootpg + resetvec code for U-Boot
731 -----------------------------------------------------------------------------------------
733 Properties / Entry arguments:
734 - filename: Filename of u-boot-br.bin (default 'u-boot-br.bin')
736 This entry is valid for PowerPC mpc85xx cpus. This entry holds
737 'bootpg + resetvec' code for PowerPC mpc85xx CPUs which needs to be
738 placed at offset 'RESET_VECTOR_ADDRESS - 0xffc'.
742 Entry: section: Entry that contains other entries
743 -------------------------------------------------
745 Properties / Entry arguments: (see binman README for more information)
746 pad-byte: Pad byte to use when padding
747 sort-by-offset: True if entries should be sorted by offset, False if
748 they must be in-order in the device tree description
749 end-at-4gb: Used to build an x86 ROM which ends at 4GB (2^32)
750 skip-at-start: Number of bytes before the first entry starts. These
751 effectively adjust the starting offset of entries. For example,
752 if this is 16, then the first entry would start at 16. An entry
753 with offset = 20 would in fact be written at offset 4 in the image
754 file, since the first 16 bytes are skipped when writing.
755 name-prefix: Adds a prefix to the name of every entry in the section
756 when writing out the map
759 allow_missing: True if this section permits external blobs to be
760 missing their contents. The second will produce an image but of
761 course it will not work.
763 Since a section is also an entry, it inherits all the properies of entries
766 A section is an entry which can contain other entries, thus allowing
767 hierarchical images to be created. See 'Sections and hierarchical images'
768 in the binman README for more information.
772 Entry: text: An entry which contains text
773 -----------------------------------------
775 The text can be provided either in the node itself or by a command-line
776 argument. There is a level of indirection to allow multiple text strings
779 Properties / Entry arguments:
780 text-label: The value of this string indicates the property / entry-arg
781 that contains the string to place in the entry
782 <xxx> (actual name is the value of text-label): contains the string to
784 <text>: The text to place in the entry (overrides the above mechanism).
785 This is useful when the text is constant.
791 text-label = "message";
796 binman -amessage="this is my message"
798 and binman will insert that string into the entry.
800 It is also possible to put the string directly in the node:
804 text-label = "message";
805 message = "a message directly in the node"
812 text = "some text directly in the node"
815 The text is not itself nul-terminated. This can be achieved, if required,
816 by setting the size of the entry to something larger than the text.
820 Entry: u-boot: U-Boot flat binary
821 ---------------------------------
823 Properties / Entry arguments:
824 - filename: Filename of u-boot.bin (default 'u-boot.bin')
826 This is the U-Boot binary, containing relocation information to allow it
827 to relocate itself at runtime. The binary typically includes a device tree
828 blob at the end of it. Use u_boot_nodtb if you want to package the device
831 U-Boot can access binman symbols at runtime. See:
833 'Access to binman entry offsets at run time (fdt)'
835 in the binman README for more information.
839 Entry: u-boot-dtb: U-Boot device tree
840 -------------------------------------
842 Properties / Entry arguments:
843 - filename: Filename of u-boot.dtb (default 'u-boot.dtb')
845 This is the U-Boot device tree, containing configuration information for
846 U-Boot. U-Boot needs this to know what devices are present and which drivers
849 Note: This is mostly an internal entry type, used by others. This allows
850 binman to know which entries contain a device tree.
854 Entry: u-boot-dtb-with-ucode: A U-Boot device tree file, with the microcode removed
855 -----------------------------------------------------------------------------------
857 Properties / Entry arguments:
858 - filename: Filename of u-boot.dtb (default 'u-boot.dtb')
860 See Entry_u_boot_ucode for full details of the three entries involved in
861 this process. This entry provides the U-Boot device-tree file, which
862 contains the microcode. If the microcode is not being collated into one
863 place then the offset and size of the microcode is recorded by this entry,
864 for use by u_boot_with_ucode_ptr. If it is being collated, then this
865 entry deletes the microcode from the device tree (to save space) and makes
866 it available to u_boot_ucode.
870 Entry: u-boot-elf: U-Boot ELF image
871 -----------------------------------
873 Properties / Entry arguments:
874 - filename: Filename of u-boot (default 'u-boot')
876 This is the U-Boot ELF image. It does not include a device tree but can be
877 relocated to any address for execution.
881 Entry: u-boot-img: U-Boot legacy image
882 --------------------------------------
884 Properties / Entry arguments:
885 - filename: Filename of u-boot.img (default 'u-boot.img')
887 This is the U-Boot binary as a packaged image, in legacy format. It has a
888 header which allows it to be loaded at the correct address for execution.
890 You should use FIT (Flat Image Tree) instead of the legacy image for new
895 Entry: u-boot-nodtb: U-Boot flat binary without device tree appended
896 --------------------------------------------------------------------
898 Properties / Entry arguments:
899 - filename: Filename of u-boot.bin (default 'u-boot-nodtb.bin')
901 This is the U-Boot binary, containing relocation information to allow it
902 to relocate itself at runtime. It does not include a device tree blob at
903 the end of it so normally cannot work without it. You can add a u_boot_dtb
904 entry after this one, or use a u_boot entry instead (which contains both
905 U-Boot and the device tree).
909 Entry: u-boot-spl: U-Boot SPL binary
910 ------------------------------------
912 Properties / Entry arguments:
913 - filename: Filename of u-boot-spl.bin (default 'spl/u-boot-spl.bin')
915 This is the U-Boot SPL (Secondary Program Loader) binary. This is a small
916 binary which loads before U-Boot proper, typically into on-chip SRAM. It is
917 responsible for locating, loading and jumping to U-Boot. Note that SPL is
918 not relocatable so must be loaded to the correct address in SRAM, or written
919 to run from the correct address if direct flash execution is possible (e.g.
922 SPL can access binman symbols at runtime. See:
924 'Access to binman entry offsets at run time (symbols)'
926 in the binman README for more information.
928 The ELF file 'spl/u-boot-spl' must also be available for this to work, since
929 binman uses that to look up symbols to write into the SPL binary.
933 Entry: u-boot-spl-bss-pad: U-Boot SPL binary padded with a BSS region
934 ---------------------------------------------------------------------
936 Properties / Entry arguments:
939 This is similar to u_boot_spl except that padding is added after the SPL
940 binary to cover the BSS (Block Started by Symbol) region. This region holds
941 the various used by SPL. It is set to 0 by SPL when it starts up. If you
942 want to append data to the SPL image (such as a device tree file), you must
943 pad out the BSS region to avoid the data overlapping with U-Boot variables.
944 This entry is useful in that case. It automatically pads out the entry size
945 to cover both the code, data and BSS.
947 The ELF file 'spl/u-boot-spl' must also be available for this to work, since
948 binman uses that to look up the BSS address.
952 Entry: u-boot-spl-dtb: U-Boot SPL device tree
953 ---------------------------------------------
955 Properties / Entry arguments:
956 - filename: Filename of u-boot.dtb (default 'spl/u-boot-spl.dtb')
958 This is the SPL device tree, containing configuration information for
959 SPL. SPL needs this to know what devices are present and which drivers
964 Entry: u-boot-spl-elf: U-Boot SPL ELF image
965 -------------------------------------------
967 Properties / Entry arguments:
968 - filename: Filename of SPL u-boot (default 'spl/u-boot-spl')
970 This is the U-Boot SPL ELF image. It does not include a device tree but can
971 be relocated to any address for execution.
975 Entry: u-boot-spl-nodtb: SPL binary without device tree appended
976 ----------------------------------------------------------------
978 Properties / Entry arguments:
979 - filename: Filename of spl/u-boot-spl-nodtb.bin (default
980 'spl/u-boot-spl-nodtb.bin')
982 This is the U-Boot SPL binary, It does not include a device tree blob at
983 the end of it so may not be able to work without it, assuming SPL needs
984 a device tree to operation on your platform. You can add a u_boot_spl_dtb
985 entry after this one, or use a u_boot_spl entry instead (which contains
986 both SPL and the device tree).
990 Entry: u-boot-spl-with-ucode-ptr: U-Boot SPL with embedded microcode pointer
991 ----------------------------------------------------------------------------
993 This is used when SPL must set up the microcode for U-Boot.
995 See Entry_u_boot_ucode for full details of the entries involved in this
1000 Entry: u-boot-tpl: U-Boot TPL binary
1001 ------------------------------------
1003 Properties / Entry arguments:
1004 - filename: Filename of u-boot-tpl.bin (default 'tpl/u-boot-tpl.bin')
1006 This is the U-Boot TPL (Tertiary Program Loader) binary. This is a small
1007 binary which loads before SPL, typically into on-chip SRAM. It is
1008 responsible for locating, loading and jumping to SPL, the next-stage
1009 loader. Note that SPL is not relocatable so must be loaded to the correct
1010 address in SRAM, or written to run from the correct address if direct
1011 flash execution is possible (e.g. on x86 devices).
1013 SPL can access binman symbols at runtime. See:
1015 'Access to binman entry offsets at run time (symbols)'
1017 in the binman README for more information.
1019 The ELF file 'tpl/u-boot-tpl' must also be available for this to work, since
1020 binman uses that to look up symbols to write into the TPL binary.
1024 Entry: u-boot-tpl-dtb: U-Boot TPL device tree
1025 ---------------------------------------------
1027 Properties / Entry arguments:
1028 - filename: Filename of u-boot.dtb (default 'tpl/u-boot-tpl.dtb')
1030 This is the TPL device tree, containing configuration information for
1031 TPL. TPL needs this to know what devices are present and which drivers
1036 Entry: u-boot-tpl-dtb-with-ucode: U-Boot TPL with embedded microcode pointer
1037 ----------------------------------------------------------------------------
1039 This is used when TPL must set up the microcode for U-Boot.
1041 See Entry_u_boot_ucode for full details of the entries involved in this
1046 Entry: u-boot-tpl-elf: U-Boot TPL ELF image
1047 -------------------------------------------
1049 Properties / Entry arguments:
1050 - filename: Filename of TPL u-boot (default 'tpl/u-boot-tpl')
1052 This is the U-Boot TPL ELF image. It does not include a device tree but can
1053 be relocated to any address for execution.
1057 Entry: u-boot-tpl-with-ucode-ptr: U-Boot TPL with embedded microcode pointer
1058 ----------------------------------------------------------------------------
1060 See Entry_u_boot_ucode for full details of the entries involved in this
1065 Entry: u-boot-ucode: U-Boot microcode block
1066 -------------------------------------------
1068 Properties / Entry arguments:
1071 The contents of this entry are filled in automatically by other entries
1072 which must also be in the image.
1074 U-Boot on x86 needs a single block of microcode. This is collected from
1075 the various microcode update nodes in the device tree. It is also unable
1076 to read the microcode from the device tree on platforms that use FSP
1077 (Firmware Support Package) binaries, because the API requires that the
1078 microcode is supplied before there is any SRAM available to use (i.e.
1079 the FSP sets up the SRAM / cache-as-RAM but does so in the call that
1080 requires the microcode!). To keep things simple, all x86 platforms handle
1081 microcode the same way in U-Boot (even non-FSP platforms). This is that
1082 a table is placed at _dt_ucode_base_size containing the base address and
1083 size of the microcode. This is either passed to the FSP (for FSP
1084 platforms), or used to set up the microcode (for non-FSP platforms).
1085 This all happens in the build system since it is the only way to get
1086 the microcode into a single blob and accessible without SRAM.
1088 There are two cases to handle. If there is only one microcode blob in
1089 the device tree, then the ucode pointer it set to point to that. This
1090 entry (u-boot-ucode) is empty. If there is more than one update, then
1091 this entry holds the concatenation of all updates, and the device tree
1092 entry (u-boot-dtb-with-ucode) is updated to remove the microcode. This
1093 last step ensures that that the microcode appears in one contiguous
1094 block in the image and is not unnecessarily duplicated in the device
1095 tree. It is referred to as 'collation' here.
1097 Entry types that have a part to play in handling microcode:
1099 Entry_u_boot_with_ucode_ptr:
1100 Contains u-boot-nodtb.bin (i.e. U-Boot without the device tree).
1101 It updates it with the address and size of the microcode so that
1102 U-Boot can find it early on start-up.
1103 Entry_u_boot_dtb_with_ucode:
1104 Contains u-boot.dtb. It stores the microcode in a
1105 'self.ucode_data' property, which is then read by this class to
1106 obtain the microcode if needed. If collation is performed, it
1107 removes the microcode from the device tree.
1109 This class. If collation is enabled it reads the microcode from
1110 the Entry_u_boot_dtb_with_ucode entry, and uses it as the
1111 contents of this entry.
1115 Entry: u-boot-with-ucode-ptr: U-Boot with embedded microcode pointer
1116 --------------------------------------------------------------------
1118 Properties / Entry arguments:
1119 - filename: Filename of u-boot-nodtb.bin (default 'u-boot-nodtb.bin')
1120 - optional-ucode: boolean property to make microcode optional. If the
1121 u-boot.bin image does not include microcode, no error will
1124 See Entry_u_boot_ucode for full details of the three entries involved in
1125 this process. This entry updates U-Boot with the offset and size of the
1126 microcode, to allow early x86 boot code to find it without doing anything
1127 complicated. Otherwise it is the same as the u_boot entry.
1131 Entry: vblock: An entry which contains a Chromium OS verified boot block
1132 ------------------------------------------------------------------------
1134 Properties / Entry arguments:
1135 - content: List of phandles to entries to sign
1136 - keydir: Directory containing the public keys to use
1137 - keyblock: Name of the key file to use (inside keydir)
1138 - signprivate: Name of provide key file to use (inside keydir)
1139 - version: Version number of the vblock (typically 1)
1140 - kernelkey: Name of the kernel key to use (inside keydir)
1141 - preamble-flags: Value of the vboot preamble flags (typically 0)
1144 - input.<unique_name> - input file passed to futility
1145 - vblock.<unique_name> - output file generated by futility (which is
1146 used as the entry contents)
1148 Chromium OS signs the read-write firmware and kernel, writing the signature
1149 in this block. This allows U-Boot to verify that the next firmware stage
1150 and kernel are genuine.
1154 Entry: x86-reset16: x86 16-bit reset code for U-Boot
1155 ----------------------------------------------------
1157 Properties / Entry arguments:
1158 - filename: Filename of u-boot-x86-reset16.bin (default
1159 'u-boot-x86-reset16.bin')
1161 x86 CPUs start up in 16-bit mode, even if they are 32-bit CPUs. This code
1162 must be placed at a particular address. This entry holds that code. It is
1163 typically placed at offset CONFIG_RESET_VEC_LOC. The code is responsible
1164 for jumping to the x86-start16 code, which continues execution.
1166 For 64-bit U-Boot, the 'x86_reset16_spl' entry type is used instead.
1170 Entry: x86-reset16-spl: x86 16-bit reset code for U-Boot
1171 --------------------------------------------------------
1173 Properties / Entry arguments:
1174 - filename: Filename of u-boot-x86-reset16.bin (default
1175 'u-boot-x86-reset16.bin')
1177 x86 CPUs start up in 16-bit mode, even if they are 32-bit CPUs. This code
1178 must be placed at a particular address. This entry holds that code. It is
1179 typically placed at offset CONFIG_RESET_VEC_LOC. The code is responsible
1180 for jumping to the x86-start16 code, which continues execution.
1182 For 32-bit U-Boot, the 'x86_reset_spl' entry type is used instead.
1186 Entry: x86-reset16-tpl: x86 16-bit reset code for U-Boot
1187 --------------------------------------------------------
1189 Properties / Entry arguments:
1190 - filename: Filename of u-boot-x86-reset16.bin (default
1191 'u-boot-x86-reset16.bin')
1193 x86 CPUs start up in 16-bit mode, even if they are 32-bit CPUs. This code
1194 must be placed at a particular address. This entry holds that code. It is
1195 typically placed at offset CONFIG_RESET_VEC_LOC. The code is responsible
1196 for jumping to the x86-start16 code, which continues execution.
1198 For 32-bit U-Boot, the 'x86_reset_tpl' entry type is used instead.
1202 Entry: x86-start16: x86 16-bit start-up code for U-Boot
1203 -------------------------------------------------------
1205 Properties / Entry arguments:
1206 - filename: Filename of u-boot-x86-start16.bin (default
1207 'u-boot-x86-start16.bin')
1209 x86 CPUs start up in 16-bit mode, even if they are 32-bit CPUs. This code
1210 must be placed in the top 64KB of the ROM. The reset code jumps to it. This
1211 entry holds that code. It is typically placed at offset
1212 CONFIG_SYS_X86_START16. The code is responsible for changing to 32-bit mode
1213 and jumping to U-Boot's entry point, which requires 32-bit mode (for 32-bit
1216 For 64-bit U-Boot, the 'x86_start16_spl' entry type is used instead.
1220 Entry: x86-start16-spl: x86 16-bit start-up code for SPL
1221 --------------------------------------------------------
1223 Properties / Entry arguments:
1224 - filename: Filename of spl/u-boot-x86-start16-spl.bin (default
1225 'spl/u-boot-x86-start16-spl.bin')
1227 x86 CPUs start up in 16-bit mode, even if they are 32-bit CPUs. This code
1228 must be placed in the top 64KB of the ROM. The reset code jumps to it. This
1229 entry holds that code. It is typically placed at offset
1230 CONFIG_SYS_X86_START16. The code is responsible for changing to 32-bit mode
1231 and jumping to U-Boot's entry point, which requires 32-bit mode (for 32-bit
1234 For 32-bit U-Boot, the 'x86-start16' entry type is used instead.
1238 Entry: x86-start16-tpl: x86 16-bit start-up code for TPL
1239 --------------------------------------------------------
1241 Properties / Entry arguments:
1242 - filename: Filename of tpl/u-boot-x86-start16-tpl.bin (default
1243 'tpl/u-boot-x86-start16-tpl.bin')
1245 x86 CPUs start up in 16-bit mode, even if they are 32-bit CPUs. This code
1246 must be placed in the top 64KB of the ROM. The reset code jumps to it. This
1247 entry holds that code. It is typically placed at offset
1248 CONFIG_SYS_X86_START16. The code is responsible for changing to 32-bit mode
1249 and jumping to U-Boot's entry point, which requires 32-bit mode (for 32-bit
1252 If TPL is not being used, the 'x86-start16-spl or 'x86-start16' entry types
1253 may be used instead.