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