1 /* SPDX-License-Identifier: BSD-3-Clause */ 2 /* 3 * This is from the Android Project, 4 * Repository: https://android.googlesource.com/platform/system/tools/mkbootimg 5 * File: include/bootimg/bootimg.h 6 * Commit: e55998a0f2b61b685d5eb4a486ca3a0c680b1a2f 7 * 8 * Copyright (C) 2007 The Android Open Source Project 9 */ 10 11 #ifndef _ANDROID_IMAGE_H_ 12 #define _ANDROID_IMAGE_H_ 13 14 #define ANDR_BOOT_MAGIC "ANDROID!" 15 #define ANDR_BOOT_MAGIC_SIZE 8 16 #define ANDR_BOOT_NAME_SIZE 16 17 #define ANDR_BOOT_ARGS_SIZE 512 18 #define ANDR_BOOT_EXTRA_ARGS_SIZE 1024 19 20 /* 21 * It is expected that callers would explicitly specify which version of the 22 * boot image header they need to use. 23 */ 24 typedef struct andr_img_hdr andr_img_hdr; 25 26 /* The bootloader expects the structure of andr_img_hdr with header 27 * version 0 to be as follows: */ 28 struct andr_img_hdr { 29 /* Must be ANDR_BOOT_MAGIC. */ 30 char magic[ANDR_BOOT_MAGIC_SIZE]; 31 32 u32 kernel_size; /* size in bytes */ 33 u32 kernel_addr; /* physical load addr */ 34 35 u32 ramdisk_size; /* size in bytes */ 36 u32 ramdisk_addr; /* physical load addr */ 37 38 u32 second_size; /* size in bytes */ 39 u32 second_addr; /* physical load addr */ 40 41 u32 tags_addr; /* physical addr for kernel tags */ 42 u32 page_size; /* flash page size we assume */ 43 44 /* Version of the boot image header. */ 45 u32 header_version; 46 47 /* Operating system version and security patch level. 48 * For version "A.B.C" and patch level "Y-M-D": 49 * (7 bits for each of A, B, C; 7 bits for (Y-2000), 4 bits for M) 50 * os_version = A[31:25] B[24:18] C[17:11] (Y-2000)[10:4] M[3:0] */ 51 u32 os_version; 52 53 char name[ANDR_BOOT_NAME_SIZE]; /* asciiz product name */ 54 55 char cmdline[ANDR_BOOT_ARGS_SIZE]; 56 57 u32 id[8]; /* timestamp / checksum / sha1 / etc */ 58 59 /* Supplemental command line data; kept here to maintain 60 * binary compatibility with older versions of mkbootimg. */ 61 char extra_cmdline[ANDR_BOOT_EXTRA_ARGS_SIZE]; 62 63 /* Fields in boot_img_hdr_v1 and newer. */ 64 u32 recovery_dtbo_size; /* size in bytes for recovery DTBO/ACPIO image */ 65 u64 recovery_dtbo_offset; /* offset to recovery dtbo/acpio in boot image */ 66 u32 header_size; 67 68 /* Fields in boot_img_hdr_v2 and newer. */ 69 u32 dtb_size; /* size in bytes for DTB image */ 70 u64 dtb_addr; /* physical load address for DTB image */ 71 } __attribute__((packed)); 72 73 /* When a boot header is of version 0, the structure of boot image is as 74 * follows: 75 * 76 * +-----------------+ 77 * | boot header | 1 page 78 * +-----------------+ 79 * | kernel | n pages 80 * +-----------------+ 81 * | ramdisk | m pages 82 * +-----------------+ 83 * | second stage | o pages 84 * +-----------------+ 85 * 86 * n = (kernel_size + page_size - 1) / page_size 87 * m = (ramdisk_size + page_size - 1) / page_size 88 * o = (second_size + page_size - 1) / page_size 89 * 90 * 0. all entities are page_size aligned in flash 91 * 1. kernel and ramdisk are required (size != 0) 92 * 2. second is optional (second_size == 0 -> no second) 93 * 3. load each element (kernel, ramdisk, second) at 94 * the specified physical address (kernel_addr, etc) 95 * 4. prepare tags at tag_addr. kernel_args[] is 96 * appended to the kernel commandline in the tags. 97 * 5. r0 = 0, r1 = MACHINE_TYPE, r2 = tags_addr 98 * 6. if second_size != 0: jump to second_addr 99 * else: jump to kernel_addr 100 */ 101 102 /* When the boot image header has a version of 2, the structure of the boot 103 * image is as follows: 104 * 105 * +---------------------+ 106 * | boot header | 1 page 107 * +---------------------+ 108 * | kernel | n pages 109 * +---------------------+ 110 * | ramdisk | m pages 111 * +---------------------+ 112 * | second stage | o pages 113 * +---------------------+ 114 * | recovery dtbo/acpio | p pages 115 * +---------------------+ 116 * | dtb | q pages 117 * +---------------------+ 118 119 * n = (kernel_size + page_size - 1) / page_size 120 * m = (ramdisk_size + page_size - 1) / page_size 121 * o = (second_size + page_size - 1) / page_size 122 * p = (recovery_dtbo_size + page_size - 1) / page_size 123 * q = (dtb_size + page_size - 1) / page_size 124 * 125 * 0. all entities are page_size aligned in flash 126 * 1. kernel, ramdisk and DTB are required (size != 0) 127 * 2. recovery_dtbo/recovery_acpio is required for recovery.img in non-A/B 128 * devices(recovery_dtbo_size != 0) 129 * 3. second is optional (second_size == 0 -> no second) 130 * 4. load each element (kernel, ramdisk, second, dtb) at 131 * the specified physical address (kernel_addr, etc) 132 * 5. If booting to recovery mode in a non-A/B device, extract recovery 133 * dtbo/acpio and apply the correct set of overlays on the base device tree 134 * depending on the hardware/product revision. 135 * 6. prepare tags at tag_addr. kernel_args[] is 136 * appended to the kernel commandline in the tags. 137 * 7. r0 = 0, r1 = MACHINE_TYPE, r2 = tags_addr 138 * 8. if second_size != 0: jump to second_addr 139 * else: jump to kernel_addr 140 */ 141 142 #endif 143