From d65e8da92ee7d594226aeee04eb0bef5d60f8bda Mon Sep 17 00:00:00 2001 From: Ruslan Trofymenko Date: Fri, 5 Jul 2019 15:37:32 +0300 Subject: common: Implement A/B metadata This patch determines the A/B-specific bootloader message structure that is the basis for implementation of recovery and A/B update functions. A/B metadata is stored in this structure and used to decide which slot should we use to boot the device. Also some basic functions for A/B metadata manipulation are implemented (like slot selection). The patch was extracted from commits [1], [2] with some coding style fixes. [1] https://android-review.googlesource.com/c/platform/external/u-boot/+/729878/2 [2] https://android-review.googlesource.com/c/platform/external/u-boot/+/729880/2 Signed-off-by: Ruslan Trofymenko Signed-off-by: Igor Opaniuk Reviewed-by: Sam Protsenko Reviewed-by: Simon Glass --- include/android_ab.h | 34 ++++++++++++++++++++++++++++++++++ 1 file changed, 34 insertions(+) create mode 100644 include/android_ab.h (limited to 'include/android_ab.h') diff --git a/include/android_ab.h b/include/android_ab.h new file mode 100644 index 0000000000..810906d22b --- /dev/null +++ b/include/android_ab.h @@ -0,0 +1,34 @@ +/* SPDX-License-Identifier: BSD-2-Clause */ +/* + * Copyright (C) 2017 The Android Open Source Project + */ + +#ifndef __ANDROID_AB_H +#define __ANDROID_AB_H + +#include + +/* Android standard boot slot names are 'a', 'b', 'c', ... */ +#define BOOT_SLOT_NAME(slot_num) ('a' + (slot_num)) + +/* Number of slots */ +#define NUM_SLOTS 2 + +/** + * Select the slot where to boot from. + * + * On Android devices with more than one boot slot (multiple copies of the + * kernel and system images) selects which slot should be used to boot from and + * registers the boot attempt. This is used in by the new A/B update model where + * one slot is updated in the background while running from the other slot. If + * the selected slot did not successfully boot in the past, a boot attempt is + * registered before returning from this function so it isn't selected + * indefinitely. + * + * @param[in] dev_desc Place to store the device description pointer + * @param[in] part_info Place to store the partition information + * @return The slot number (>= 0) on success, or a negative on error + */ +int ab_select_slot(struct blk_desc *dev_desc, disk_partition_t *part_info); + +#endif /* __ANDROID_AB_H */ -- cgit v1.2.3