On Mon, 18 Feb 2019 at 09:22, Igor Opaniuk <igor.opan...@linaro.org> wrote: > > From: Ruslan Trofymenko <ruslan.trofyme...@linaro.org> > > Add support for A/B boot process on AM57xx based boards: > > 1. Define 'slot_suffix' variable (using 'ab_select' command) > 2. Extend 'emmc_android_boot' boot command (add commands for A/B boot > process) > > 'ab_select' command is used to decide which slot should be used for > booting up. A/B metadata resides in 'misc' partition. > > To activate the A/B boot process, the following config options must be > set: > > CONFIG_ANDROID_AB=y > CONFIG_CMD_AB_SELECT=y > > For successful A/B boot, the corresponding A/B infrastructure must be > involved on Android side [1] (including mounting system as root), and > disk must be partitioned accordingly. > > When A/B boot is enabled, there are some known limitations currently > exist (not related to A/B patches, need to be implemented later): > > 1. The 'Verified Boot' sequence is not supported > 2. dev path to system partition (system_a or system_b) is passed via > 'bootargs' as 'root=' argument like 'root=/dev/mmcblk1p12', but > further we'll need to rework it with respect to dm-verity > requirements [2] > > In case when A/B partitions are not present in system (and A/B boot is > enabled), boot up process will be terminated and next message will be > shown: > > "boot_a(b) partition not found" > > [1] https://source.android.com/devices/tech/ota/ab > [2] https://source.android.com/devices/tech/ota/ab/ab_implement#kernel > > Signed-off-by: Ruslan Trofymenko <ruslan.trofyme...@linaro.org> > Signed-off-by: Igor Opaniuk <igor.opan...@linaro.org> > Reviewed-by: Alistair Strachan <astrac...@google.com> > Reviewed-by: Sam Protsenko <semen.protse...@linaro.org> > --- > > Changes in v3: None > > Changes in v2: > * Add changes related to command renaming (android_ab_select -> ab_select). > * Slotted sections (e.g. system_a and system_b) are added to the > default sections if CONFIG_CMD_AB_SELECT flag is defined > * Rebased on top of master > * system partitions sizes increased to 1024 MiB (to be consistent with > recent changes to boot.h file) > > include/environment/ti/boot.h | 58 > ++++++++++++++++++++++++++++++++++++++----- > 1 file changed, 52 insertions(+), 6 deletions(-)
Reviewed-by: Simon Glass <s...@chromium.org> _______________________________________________ U-Boot mailing list U-Boot@lists.denx.de https://lists.denx.de/listinfo/u-boot