1 /* ----------------------------------------------------------------------- * 2 * 3 * Copyright (C) 2009 Intel Corporation. All rights reserved. 4 * 5 * This program is free software; you can redistribute it and/or 6 * modify it under the terms of the GNU General Public License version 7 * 2 as published by the Free Software Foundation. 8 * 9 * This program is distributed in the hope that it will be useful, 10 * but WITHOUT ANY WARRANTY; without even the implied warranty of 11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 12 * GNU General Public License for more details. 13 * 14 * You should have received a copy of the GNU General Public License 15 * along with this program; if not, write to the Free Software 16 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 17 * 02110-1301, USA. 18 * 19 * H. Peter Anvin <hpa@linux.intel.com> 20 * 21 * ----------------------------------------------------------------------- */ 22 23 /* 24 * Compute the desired load offset from a compressed program; outputs 25 * a small assembly wrapper with the appropriate symbols defined. 26 */ 27 28 #include <stdlib.h> 29 #include <stdio.h> 30 #include <string.h> 31 #include <inttypes.h> 32 33 static uint32_t getle32(const void *p) 34 { 35 const uint8_t *cp = p; 36 37 return (uint32_t)cp[0] + ((uint32_t)cp[1] << 8) + 38 ((uint32_t)cp[2] << 16) + ((uint32_t)cp[3] << 24); 39 } 40 41 int main(int argc, char *argv[]) 42 { 43 uint32_t olen; 44 long ilen; 45 unsigned long offs; 46 FILE *f; 47 48 if (argc < 2) { 49 fprintf(stderr, "Usage: %s compressed_file\n", argv[0]); 50 return 1; 51 } 52 53 /* Get the information for the compressed kernel image first */ 54 55 f = fopen(argv[1], "r"); 56 if (!f) { 57 perror(argv[1]); 58 return 1; 59 } 60 61 62 if (fseek(f, -4L, SEEK_END)) { 63 perror(argv[1]); 64 } 65 fread(&olen, sizeof olen, 1, f); 66 ilen = ftell(f); 67 olen = getle32(&olen); 68 fclose(f); 69 70 /* 71 * Now we have the input (compressed) and output (uncompressed) 72 * sizes, compute the necessary decompression offset... 73 */ 74 75 offs = (olen > ilen) ? olen - ilen : 0; 76 offs += olen >> 12; /* Add 8 bytes for each 32K block */ 77 offs += 32*1024 + 18; /* Add 32K + 18 bytes slack */ 78 offs = (offs+4095) & ~4095; /* Round to a 4K boundary */ 79 80 printf(".section \".rodata.compressed\",\"a\",@progbits\n"); 81 printf(".globl z_input_len\n"); 82 printf("z_input_len = %lu\n", ilen); 83 printf(".globl z_output_len\n"); 84 printf("z_output_len = %lu\n", (unsigned long)olen); 85 printf(".globl z_extract_offset\n"); 86 printf("z_extract_offset = 0x%lx\n", offs); 87 /* z_extract_offset_negative allows simplification of head_32.S */ 88 printf(".globl z_extract_offset_negative\n"); 89 printf("z_extract_offset_negative = -0x%lx\n", offs); 90 91 printf(".globl input_data, input_data_end\n"); 92 printf("input_data:\n"); 93 printf(".incbin \"%s\"\n", argv[1]); 94 printf("input_data_end:\n"); 95 96 return 0; 97 } 98