25 Jul, 2019
3 commits
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These have been reported by Simon in [1] and fixed in [2].
However, since [1] has already been pushed to u-boot/master, the
improvements incorporated in [2] are now extracted and resubmitted.The changes are in the area of coding style and best practices:
* s/field/fieldp/, s/size/sizep/, to convey that the variables return
an output to the caller
* s/err_1/err_read_fail/, s/err_2/err_too_small/, to be more descriptive
* Made sure 'static int do_bcb_load' appears on the same line
* Placed a `/*` on top of multi-line comment[1] https://patchwork.ozlabs.org/patch/1104244/#2200259
[2] https://patchwork.ozlabs.org/cover/1128661/
("[v4,0/4] Add 'bcb' command to read/modify/write Android BCB")Fixes: db7b7a05b267 ("cmd: Add 'bcb' command to read/modify/write BCB fields")
Reported-by: Simon Glass
Signed-off-by: Eugeniu Rosca
Reviewed-by: Sam Protsenko -
Quote from https://patchwork.ozlabs.org/patch/1104244/#2210814:
----------8
Signed-off-by: Eugeniu Rosca
Reviewed-by: Sam Protsenko
Reviewed-by: Igor Opaniuk -
Fix warning V1037 reported by PVS-Studio Static Analyzer:
Two or more case-branches perform the same actions. Check lines: 49, 53Fixes: db7b7a05b267 ("cmd: Add 'bcb' command to read/modify/write BCB fields")
Signed-off-by: Eugeniu Rosca
Reviewed-by: Igor Opaniuk
Reviewed-by: Sam Protsenko
12 Jul, 2019
1 commit
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'Bootloader Control Block' (BCB) is a well established term/acronym in
the Android namespace which refers to a location in a dedicated raw
(i.e. FS-unaware) flash (e.g. eMMC) partition, usually called "misc",
which is used as media for exchanging messages between Android userspace
(particularly recovery [1]) and an Android-capable bootloader.On higher level, this allows implementing a subset of Android Bootloader
Requirements [2], amongst which is the Android-specific bootloader
flow [3]. Regardless how the latter is implemented in U-Boot ([3] being
the most memorable example), reading/writing/dumping the BCB fields in
the development process from inside the U-Boot is a convenient feature.
Hence, make it available to the users.Some usage examples of the new command recorded on R-Car H3ULCB-KF
('>>>' is an overlay on top of the original console output):=> bcb
bcb - Load/set/clear/test/dump/store Android BCB fieldsUsage:
bcb load - load BCB from mmc :
bcb set - set BCB to
bcb clear [] - clear BCB or all fields
bcb test - test BCB against
bcb dump - dump BCB
bcb store - store BCB back to mmcLegend:
- MMC device index containing the BCB partition
- MMC partition index or name containing the BCB
- one of {command,status,recovery,stage,reserved}
- the binary operator used in 'bcb test':
'=' returns true if matches the string stored in
'~' returns true if matches a subset of 's string
- string/text provided as input to bcb {set,test}
NOTE: any ':' character in will be replaced by line feed
during 'bcb set' and used as separator by upper layers=> bcb dump command
Error: Please, load BCB first!
>>> Users must specify mmc device and partition before any other call=> bcb load 1 misc
=> bcb load 1 1
>>> The two calls are equivalent (assuming "misc" has index 1)=> bcb dump command
00000000: 62 6f 6f 74 6f 6e 63 65 2d 73 68 65 6c 6c 00 72 bootonce-shell.r
00000010: 79 00 72 00 00 00 00 00 00 00 00 00 00 00 00 00 y.r.............
>>> The output is in binary/string format for convenience
>>> The output size matches the size of inspected BCB field
>>> (32 bytes in case of 'command')=> bcb test command = bootonce-shell && echo true
true
=> bcb test command = bootonce-shell- && echo true
=> bcb test command = bootonce-shel && echo true
>>> The '=' operator returns 'true' on perfect match=> bcb test command ~ bootonce-shel && echo true
true
=> bcb test command ~ bootonce-shell && echo true
true
>>> The '~' operator returns 'true' on substring match=> bcb set command recovery
=> bcb dump command
00000000: 72 65 63 6f 76 65 72 79 00 73 68 65 6c 6c 00 72 recovery.shell.r
00000010: 79 00 72 00 00 00 00 00 00 00 00 00 00 00 00 00 y.r.............
>>> The new value is NULL-terminated and stored in the BCB field=> bcb set recovery "msg1:msg2:msg3"
=> bcb dump recovery
00000040: 6d 73 67 31 0a 6d 73 67 32 0a 6d 73 67 33 00 00 msg1.msg2.msg3..
00000050: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
00000060: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
>>> --- snip ---
>>> Every ':' is replaced by line-feed '\n' (0xA). The latter is used
>>> as separator between individual commands by Android userspace=> bcb store
>>> Flush/store the BCB structure to MMC[1] https://android.googlesource.com/platform/bootable/recovery
[2] https://source.android.com/devices/bootloader
[3] https://patchwork.ozlabs.org/patch/746835/
("[U-Boot,5/6] Initial support for the Android Bootloader flow")Signed-off-by: Eugeniu Rosca
