1 /* 2 * This is from the Android Project, 3 * Repository: https://android.googlesource.com/platform/system/core/ 4 * File: mkbootimg/bootimg.h 5 * Commit: d162828814b08ada310846a33205befb69ef5799 6 * 7 * Copyright (C) 2008 The Android Open Source Project 8 * 9 * SPDX-License-Identifier: BSD-2-Clause 10 */ 11 12 #ifndef _ANDROID_IMAGE_H_ 13 #define _ANDROID_IMAGE_H_ 14 15 typedef struct andr_img_hdr andr_img_hdr; 16 17 #define ANDR_BOOT_MAGIC "ANDROID!" 18 #define ANDR_BOOT_MAGIC_SIZE 8 19 #define ANDR_BOOT_NAME_SIZE 16 20 #define ANDR_BOOT_ARGS_SIZE 512 21 #define ANDR_BOOT_EXTRA_ARGS_SIZE 1024 22 23 struct andr_img_hdr { 24 char magic[ANDR_BOOT_MAGIC_SIZE]; 25 26 u32 kernel_size; /* size in bytes */ 27 u32 kernel_addr; /* physical load addr */ 28 29 u32 ramdisk_size; /* size in bytes */ 30 u32 ramdisk_addr; /* physical load addr */ 31 32 u32 second_size; /* size in bytes */ 33 u32 second_addr; /* physical load addr */ 34 35 u32 tags_addr; /* physical addr for kernel tags */ 36 u32 page_size; /* flash page size we assume */ 37 u32 unused; /* reserved for future expansion: MUST be 0 */ 38 39 /* operating system version and security patch level; for 40 * version "A.B.C" and patch level "Y-M-D": 41 * ver = A << 14 | B << 7 | C (7 bits for each of A, B, C) 42 * lvl = ((Y - 2000) & 127) << 4 | M (7 bits for Y, 4 bits for M) 43 * os_version = ver << 11 | lvl */ 44 u32 os_version; 45 46 char name[ANDR_BOOT_NAME_SIZE]; /* asciiz product name */ 47 48 char cmdline[ANDR_BOOT_ARGS_SIZE]; 49 50 u32 id[8]; /* timestamp / checksum / sha1 / etc */ 51 52 /* Supplemental command line data; kept here to maintain 53 * binary compatibility with older versions of mkbootimg */ 54 char extra_cmdline[ANDR_BOOT_EXTRA_ARGS_SIZE]; 55 } __attribute__((packed)); 56 57 /* 58 * +-----------------+ 59 * | boot header | 1 page 60 * +-----------------+ 61 * | kernel | n pages 62 * +-----------------+ 63 * | ramdisk | m pages 64 * +-----------------+ 65 * | second stage | o pages 66 * +-----------------+ 67 * 68 * n = (kernel_size + page_size - 1) / page_size 69 * m = (ramdisk_size + page_size - 1) / page_size 70 * o = (second_size + page_size - 1) / page_size 71 * 72 * 0. all entities are page_size aligned in flash 73 * 1. kernel and ramdisk are required (size != 0) 74 * 2. second is optional (second_size == 0 -> no second) 75 * 3. load each element (kernel, ramdisk, second) at 76 * the specified physical address (kernel_addr, etc) 77 * 4. prepare tags at tag_addr. kernel_args[] is 78 * appended to the kernel commandline in the tags. 79 * 5. r0 = 0, r1 = MACHINE_TYPE, r2 = tags_addr 80 * 6. if second_size != 0: jump to second_addr 81 * else: jump to kernel_addr 82 */ 83 #endif 84