linux-stable-rt/arch/x86/boot/compressed/mkpiggy.c

103 lines
2.8 KiB
C

/* ----------------------------------------------------------------------- *
*
* Copyright (C) 2009 Intel Corporation. All rights reserved.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License version
* 2 as published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
* 02110-1301, USA.
*
* H. Peter Anvin <hpa@linux.intel.com>
*
* ----------------------------------------------------------------------- */
/*
* Compute the desired load offset from a compressed program; outputs
* a small assembly wrapper with the appropriate symbols defined.
*/
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <inttypes.h>
static uint32_t getle32(const void *p)
{
const uint8_t *cp = p;
return (uint32_t)cp[0] + ((uint32_t)cp[1] << 8) +
((uint32_t)cp[2] << 16) + ((uint32_t)cp[3] << 24);
}
int main(int argc, char *argv[])
{
uint32_t olen;
long ilen;
unsigned long offs;
FILE *f;
if (argc < 2) {
fprintf(stderr, "Usage: %s compressed_file\n", argv[0]);
return 1;
}
/* Get the information for the compressed kernel image first */
f = fopen(argv[1], "r");
if (!f) {
perror(argv[1]);
return 1;
}
if (fseek(f, -4L, SEEK_END)) {
perror(argv[1]);
}
if (fread(&olen, sizeof(olen), 1, f) != 1) {
perror(argv[1]);
return 1;
}
ilen = ftell(f);
olen = getle32(&olen);
fclose(f);
/*
* Now we have the input (compressed) and output (uncompressed)
* sizes, compute the necessary decompression offset...
*/
offs = (olen > ilen) ? olen - ilen : 0;
offs += olen >> 12; /* Add 8 bytes for each 32K block */
offs += 64*1024 + 128; /* Add 64K + 128 bytes slack */
offs = (offs+4095) & ~4095; /* Round to a 4K boundary */
printf(".section \".rodata..compressed\",\"a\",@progbits\n");
printf(".globl z_input_len\n");
printf("z_input_len = %lu\n", ilen);
printf(".globl z_output_len\n");
printf("z_output_len = %lu\n", (unsigned long)olen);
printf(".globl z_extract_offset\n");
printf("z_extract_offset = 0x%lx\n", offs);
/* z_extract_offset_negative allows simplification of head_32.S */
printf(".globl z_extract_offset_negative\n");
printf("z_extract_offset_negative = -0x%lx\n", offs);
printf(".globl input_data, input_data_end\n");
printf("input_data:\n");
printf(".incbin \"%s\"\n", argv[1]);
printf("input_data_end:\n");
return 0;
}