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 #define ENUM_MERGE_STATUS_NONE (0) 16 #define ENUM_MERGE_STATUS_UNKNOWN (1) 17 #define ENUM_MERGE_STATUS_SNAPSHOTTED (2) 18 #define ENUM_MERGE_STATUS_MERGING (3) 19 #define ENUM_MERGE_STATUS_CANCELLED (4) 20 #define MISC_VIRTUAL_AB_MAGIC_HEADER (0x56740AB0) 21 22 struct misc_virtual_ab_message { 23 u8 version; 24 u32 magic; 25 u8 merge_status; 26 u8 source_slot; 27 u8 reserved[57]; 28 u8 reserved2[448]; 29 } __packed; 30 31 /** android_ab_select - Select the slot where to boot from. 32 * On Android devices with more than one boot slot (multiple copies of the 33 * kernel and system images) selects which slot should be used to boot from and 34 * registers the boot attempt. This is used in by the new A/B update model where 35 * one slot is updated in the background while running from the other slot. If 36 * the selected slot did not successfully boot in the past, a boot attempt is 37 * registered before returning from this function so it isn't selected 38 * indefinitely. 39 * 40 * @dev_desc: Place to store the device description pointer. 41 * @part_info: Place to store the partition information. 42 * @return the slot number (0-based) on success, or -1 on error. 43 */ 44 int android_ab_select(struct blk_desc *dev_desc, disk_partition_t *part_info); 45 46 /* Read or write the Virtual A/B message from 32KB offset in /misc.*/ 47 int read_misc_virtual_ab_message(struct misc_virtual_ab_message *message); 48 int write_misc_virtual_ab_message(struct misc_virtual_ab_message *message); 49 50 void ab_update_root_partition(void); 51 int ab_get_slot_suffix(char *slot_suffix); 52 int ab_is_support_dynamic_partition(struct blk_desc *dev_desc); 53 int ab_decrease_tries(void); 54 bool ab_can_find_recovery_part(void); 55 56 #endif 57