[U-Boot] [PATCH 0/7] android: Implement A/B boot process
Sam Protsenko
semen.protsenko at linaro.org
Wed Nov 28 14:38:45 UTC 2018
Hi Ruslan,
On Tue, Nov 27, 2018 at 9:57 PM Ruslan Trofymenko
<ruslan.trofymenko at linaro.org> wrote:
>
> This patch series adds support for Android A/B boot process [1].
> Main steps of A/B boot process are:
> - A/B metadata integrity check
> - looking for the current slot (where the system should be
> booting from)
> - getting the name of the current boot partition (boot_a or boot_b)
> and loading the corresponding Android boot image
> - getting the name of the current system partition (system_a or
> system_b) and passing of its full name via kernel command line
> (like 'root=/dev/mmcblk1p11')
> - passing current slot via kernel command line (like
> 'androidboot.slot_suffix=_a') and via A/B metadata (e.g. via
> misc partition)
> - A/B metadata processing: setting the boot success flag for
> current slot, handling the retry counter, etc
>
> A/B metadata is organized according to Android reference [2] and stored
> on 'misc' partition. On the first A/B boot process, when 'misc'
> partition doesn't contain required data, default A/B metadata will be
> created and stored in 'misc' partition. In the end of the Android boot,
> 'update_verifier' and 'update_engine' services are processing the
> A/B metadata through the Boot Control HAL. To confirm the boot was
> successful using current slot, "boot success" flag must be set on
> Android side.
>
> To enable Android A/B support in U-Boot:
> 1. Set the following config options:
>
> CONFIG_ANDROID_AB=y
> CONFIG_CMD_ANDROID_AB_SELECT=y
>
> 2. Change the disk layout so that it has sloted boot partitions.
> E.g. instead of 'boot' and 'system' partitions there should be
> 'boot_a', 'boot_b', 'system_a' and 'system_b' partitions.
>
> To be able to actually test this patch series, the A/B features must
> be implemented and enabled in Android as well (see [1] for details).
>
> Documentation and corresponding test for A/B boot is present here. The
> last patch in this series integrates A/B boot support on AM57xx based
> boards (though it's not enabled by default). Future users of A/B boot
> feature can use it as a reference.
>
> This series is a part of previous submission [3] by Alex Deymo. It
> contains only A/B feature that was stripped out from there with some
> modifications for using with "bootm" command preferred in upstream.
>
> [1] https://source.android.com/devices/tech/ota/ab/ab_implement
> [2] bootable/recovery/bootloader_message/include/bootloader_message/bootloader_message.h
> [3] https://lists.denx.de/pipermail/u-boot/2017-April/285841.html
>
> Ruslan Trofymenko (7):
> cmd: part: Add 'number' sub-command
> disk: part: Extend API to get partition info
> common: Implement A/B metadata
> cmd: Add 'android_ab_select' command
> test/py: Add base test case for A/B updates
> doc: android: Add simple guide for A/B updates
> env: am57xx: Implement A/B boot process
>
> cmd/Kconfig | 11 ++
> cmd/Makefile | 1 +
> cmd/android_ab_select.c | 53 +++++++
> cmd/part.c | 16 +-
> common/Kconfig | 10 ++
> common/Makefile | 1 +
> common/android_ab.c | 278 +++++++++++++++++++++++++++++++++++
> configs/sandbox_defconfig | 2 +
> disk/part.c | 68 +++++++++
> doc/README.android-ab | 67 +++++++++
> include/android_ab.h | 34 +++++
> include/android_bootloader_message.h | 164 +++++++++++++++++++++
> include/environment/ti/boot.h | 44 +++++-
> include/part.h | 21 +++
> test/py/tests/test_ab.py | 74 ++++++++++
> 15 files changed, 839 insertions(+), 5 deletions(-)
> create mode 100644 cmd/android_ab_select.c
> create mode 100644 common/android_ab.c
> create mode 100644 doc/README.android-ab
> create mode 100644 include/android_ab.h
> create mode 100644 include/android_bootloader_message.h
> create mode 100644 test/py/tests/test_ab.py
>
> --
> 2.7.4
>
For the whole series:
Reviewed-by: Sam Protsenko <semen.protsenko at linaro.org>
Thanks.
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