1 /* 2 * (C) Copyright 2007-2011 3 * Allwinner Technology Co., Ltd. <www.allwinnertech.com> 4 * Tom Cubie <tangliang@allwinnertech.com> 5 * 6 * a simple tool to generate bootable image for sunxi platform. 7 * 8 * SPDX-License-Identifier: GPL-2.0+ 9 */ 10 #include <fcntl.h> 11 #include <stdio.h> 12 #include <unistd.h> 13 #include <stdlib.h> 14 #include <string.h> 15 #include <errno.h> 16 #include <sys/types.h> 17 #include <sys/stat.h> 18 19 /* boot head definition from sun4i boot code */ 20 struct boot_file_head { 21 uint32_t b_instruction; /* one intruction jumping to real code */ 22 uint8_t magic[8]; /* ="eGON.BT0" or "eGON.BT1", not C-style str */ 23 uint32_t check_sum; /* generated by PC */ 24 uint32_t length; /* generated by PC */ 25 /* 26 * We use a simplified header, only filling in what is needed 27 * by the boot ROM. To be compatible with Allwinner tools we 28 * would need to implement the proper fields here instead of 29 * padding. 30 */ 31 uint8_t pad[12]; /* align to 32 bytes */ 32 }; 33 34 #define BOOT0_MAGIC "eGON.BT0" 35 #define STAMP_VALUE 0x5F0A6C39 36 37 /* check sum functon from sun4i boot code */ 38 int gen_check_sum(struct boot_file_head *head_p) 39 { 40 uint32_t length; 41 uint32_t *buf; 42 uint32_t loop; 43 uint32_t i; 44 uint32_t sum; 45 46 length = head_p->length; 47 if ((length & 0x3) != 0) /* must 4-byte-aligned */ 48 return -1; 49 buf = (uint32_t *)head_p; 50 head_p->check_sum = STAMP_VALUE; /* fill stamp */ 51 loop = length >> 2; 52 53 /* calculate the sum */ 54 for (i = 0, sum = 0; i < loop; i++) 55 sum += buf[i]; 56 57 /* write back check sum */ 58 head_p->check_sum = sum; 59 60 return 0; 61 } 62 63 #define ALIGN(x, a) __ALIGN_MASK((x), (typeof(x))(a)-1) 64 #define __ALIGN_MASK(x, mask) (((x)+(mask))&~(mask)) 65 66 #define SUN4I_SRAM_SIZE 0x7600 /* 0x7748+ is used by BROM */ 67 #define SRAM_LOAD_MAX_SIZE (SUN4I_SRAM_SIZE - sizeof(struct boot_file_head)) 68 #define BLOCK_SIZE 512 69 70 struct boot_img { 71 struct boot_file_head header; 72 char code[SRAM_LOAD_MAX_SIZE]; 73 char pad[BLOCK_SIZE]; 74 }; 75 76 int main(int argc, char *argv[]) 77 { 78 int fd_in, fd_out; 79 struct boot_img img; 80 unsigned file_size; 81 int count; 82 83 if (argc < 2) { 84 printf("\tThis program makes an input bin file to sun4i " \ 85 "bootable image.\n" \ 86 "\tUsage: %s input_file out_putfile\n", argv[0]); 87 return EXIT_FAILURE; 88 } 89 90 fd_in = open(argv[1], O_RDONLY); 91 if (fd_in < 0) { 92 perror("Open input file"); 93 return EXIT_FAILURE; 94 } 95 96 memset(img.pad, 0, BLOCK_SIZE); 97 98 /* get input file size */ 99 file_size = lseek(fd_in, 0, SEEK_END); 100 101 if (file_size > SRAM_LOAD_MAX_SIZE) { 102 fprintf(stderr, "ERROR: File too large!\n"); 103 return EXIT_FAILURE; 104 } 105 106 fd_out = open(argv[2], O_WRONLY | O_CREAT, 0666); 107 if (fd_out < 0) { 108 perror("Open output file"); 109 return EXIT_FAILURE; 110 } 111 112 /* read file to buffer to calculate checksum */ 113 lseek(fd_in, 0, SEEK_SET); 114 count = read(fd_in, img.code, file_size); 115 if (count != file_size) { 116 perror("Reading input image"); 117 return EXIT_FAILURE; 118 } 119 120 /* fill the header */ 121 img.header.b_instruction = /* b instruction */ 122 0xEA000000 | /* jump to the first instr after the header */ 123 ((sizeof(struct boot_file_head) / sizeof(int) - 2) 124 & 0x00FFFFFF); 125 memcpy(img.header.magic, BOOT0_MAGIC, 8); /* no '0' termination */ 126 img.header.length = 127 ALIGN(file_size + sizeof(struct boot_file_head), BLOCK_SIZE); 128 gen_check_sum(&img.header); 129 130 count = write(fd_out, &img, img.header.length); 131 if (count != img.header.length) { 132 perror("Writing output"); 133 return EXIT_FAILURE; 134 } 135 136 close(fd_in); 137 close(fd_out); 138 139 return EXIT_SUCCESS; 140 } 141