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 /* Bootloader Message 21 * 22 * This structure describes the content of a block in flash 23 * that is used for recovery and the bootloader to talk to 24 * each other. 25 * 26 * The command field is updated by linux when it wants to 27 * reboot into recovery or to update radio or bootloader firmware. 28 * It is also updated by the bootloader when firmware update 29 * is complete (to boot into recovery for any final cleanup) 30 * 31 * The status field is written by the bootloader after the 32 * completion of an "update-radio" or "update-hboot" command. 33 * 34 * The recovery field is only written by linux and used 35 * for the system to send a message to recovery or the 36 * other way around. 37 * 38 * The stage field is written by packages which restart themselves 39 * multiple times, so that the UI can reflect which invocation of the 40 * package it is. If the value is of the format "#/#" (eg, "1/3"), 41 * the UI will add a simple indicator of that status. 42 * 43 * The slot_suffix field is used for A/B implementations where the 44 * bootloader does not set the androidboot.ro.boot.slot_suffix kernel 45 * commandline parameter. This is used by fs_mgr to mount /system and 46 * other partitions with the slotselect flag set in fstab. A/B 47 * implementations are free to use all 32 bytes and may store private 48 * data past the first NUL-byte in this field. 49 */ 50 struct bootloader_message { 51 char command[32]; 52 char status[32]; 53 char recovery[768]; 54 55 // The 'recovery' field used to be 1024 bytes. It has only ever 56 // been used to store the recovery command line, so 768 bytes 57 // should be plenty. We carve off the last 256 bytes to store the 58 // stage string (for multistage packages) and possible future 59 // expansion. 60 char stage[32]; 61 char slot_suffix[32]; 62 char reserved[192]; 63 }; 64 65 /* Read and write the bootloader command from the "misc" partition. 66 * These return zero on success. 67 */ 68 int get_bootloader_message(struct bootloader_message *out); 69 int set_bootloader_message(const struct bootloader_message *in); 70 71 #endif 72