1 /* 2 * Copyright (C) 2017 The Android Open Source Project 3 * 4 * SPDX-License-Identifier: BSD-2-Clause 5 */ 6 7 #ifndef __ANDROID_AB_H 8 #define __ANDROID_AB_H 9 10 #include <common.h> 11 12 /* Android standard boot slot names are 'a', 'b', 'c', ... */ 13 #define ANDROID_BOOT_SLOT_NAME(slot_num) ('a' + (slot_num)) 14 15 /* Number of slots */ 16 #define ANDROID_NUM_SLOTS 2 17 18 /** android_ab_select - Select the slot where to boot from. 19 * On Android devices with more than one boot slot (multiple copies of the 20 * kernel and system images) selects which slot should be used to boot from and 21 * registers the boot attempt. This is used in by the new A/B update model where 22 * one slot is updated in the background while running from the other slot. If 23 * the selected slot did not successfully boot in the past, a boot attempt is 24 * registered before returning from this function so it isn't selected 25 * indefinitely. 26 * 27 * @dev_desc: Place to store the device description pointer. 28 * @part_info: Place to store the partition information. 29 * @return the slot number (0-based) on success, or -1 on error. 30 */ 31 int android_ab_select(struct blk_desc *dev_desc, disk_partition_t *part_info); 32 33 #endif 34