1 /* 2 * Copyright (C) 2008 The Android Open Source Project 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17 #ifndef _RECOVERY_BOOTLOADER_H 18 #define _RECOVERY_BOOTLOADER_H 19 20 #include "common.h" 21 22 static const int BOOTLOADER_MESSAGE_OFFSET_IN_MISC = 16 * 1024; 23 #define MISC_OFFSET 2048 //A,B 结构体在偏移2K 的位置 24 #define MISC_OFFSET_CMDLINE 6144 //擦除命令，在偏移4K 的位置，配合挂载脚本使用 25 #define MISC_OFFSET_CUSTOM (10 * 1024) //CUSTOM, 8K (10K), length 1K 26 27 #define MISC_PAGES_AB 2 // A,B 结构体存在 2 PAGE内 28 #define MISC_COMMAND_PAGE_AB 1 // A,B 结构体存在 1 PAGE处，即2k 29 30 #define AB_SLOT_NUM 2 31 32 /* Magic for the A/B struct when serialized. */ 33 #define AVB_AB_MAGIC "\0AB0" 34 #define AVB_AB_MAGIC_LEN 4 35 36 /* Versioning for the on-disk A/B metadata - keep in sync with avbtool. */ 37 #define AVB_AB_MAJOR_VERSION 1 38 #define AVB_AB_MINOR_VERSION 0 39 40 /* Size of AvbABData struct. */ 41 #define AVB_AB_DATA_SIZE 32 42 43 /* Maximum values for slot data */ 44 #define AVB_AB_MAX_PRIORITY 15 45 #define AVB_AB_MAX_TRIES_REMAINING 7 46 47 #define CMD_WIPE_USERDATA "cmd_wipe_userdata" 48 49 /* Bootloader Message 50 * 51 * This structure describes the content of a block in flash 52 * that is used for recovery and the bootloader to talk to 53 * each other. 54 * 55 * The command field is updated by linux when it wants to 56 * reboot into recovery or to update radio or bootloader firmware. 57 * It is also updated by the bootloader when firmware update 58 * is complete (to boot into recovery for any final cleanup) 59 * 60 * The status field is written by the bootloader after the 61 * completion of an "update-radio" or "update-hboot" command. 62 * 63 * The recovery field is only written by linux and used 64 * for the system to send a message to recovery or the 65 * other way around. 66 * 67 * The systemFlag field is used for the system to send a message to recovery. 68 */ 69 struct bootloader_message { 70 char command[32]; 71 char status[32]; 72 char recovery[768]; 73 char needupdate[4]; 74 char systemFlag[252]; 75 }; 76 77 /* Read and write the bootloader command from the "misc" partition. 78 * These return zero on success. 79 */ 80 int get_bootloader_message(struct bootloader_message *out); 81 int set_bootloader_message(const struct bootloader_message *in); 82 83 typedef struct AvbABSlotData { 84 /* Slot priority. Valid values range from 0 to AVB_AB_MAX_PRIORITY, 85 * both inclusive with 1 being the lowest and AVB_AB_MAX_PRIORITY 86 * being the highest. The special value 0 is used to indicate the 87 * slot is unbootable. 88 */ 89 unsigned char priority;//0,14,15 90 91 /* Number of times left attempting to boot this slot ranging from 0 92 * to AVB_AB_MAX_TRIES_REMAINING. 93 */ 94 unsigned char tries_remaining;//7--,成功启动，设为0 95 96 /* Non-zero if this slot has booted successfully, 0 otherwise. */ 97 unsigned char successful_boot;//0,1 98 99 /* Reserved for future use. */ 100 unsigned char reserved[1]; 101 } AvbABSlotData; 102 103 /* Struct used for recording A/B metadata. 104 * 105 * When serialized, data is stored in network byte-order. 106 */ 107 typedef struct AvbABData { 108 /* Magic number used for identification - see AVB_AB_MAGIC. */ 109 unsigned char magic[AVB_AB_MAGIC_LEN]; 110 111 /* Version of on-disk struct - see AVB_AB_{MAJOR,MINOR}_VERSION. */ 112 unsigned char version_major; //AVB_AB_MAJOR_VERSION 113 unsigned char version_minor; //AVB_AB_MINOR_VERSION 114 115 /* Padding to ensure |slots| field start eight bytes in. */ 116 unsigned char reserved1[2]; 117 118 /* Per-slot metadata. */ 119 AvbABSlotData slots[2]; 120 121 /* Reserved for future use. */ 122 unsigned char last_boot;//默认a，上一次成功启动slot的标志位，0-->a，1-->b 123 unsigned char reserved2[11]; 124 125 /* CRC32 of all 28 bytes preceding this field. */ 126 unsigned int crc32; 127 } AvbABData; 128 129 int setSlotActivity(); 130 int setSlotSucceed(); 131 void miscDisplay() ; 132 int wipe_userdata(int auto_reboot); 133 int writeCustomMiscCmdline(void); 134 int readCustomMiscCmdline(void); 135 int cleanCustomMiscCmdline(void); 136 137 //bool wipe_userdata(bool auto_reboot); 138 139 #endif 140