/*
 * flash_rom.c: Flash programming utility for SiS 630/950 M/Bs
 *
 *
 * Copyright 2000 Silicon Integrated System Corporation
 * Copyright 2004 Tyan Corp
 *	yhlu yhlu@tyan.com add exclude start and end option
 *
 *	This program is free software; you can redistribute it and/or modify
 *	it under the terms of the GNU General Public License as published by
 *	the Free Software Foundation; either version 2 of the License, or
 *	(at your option) any later version.
 *
 *	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., 675 Mass Ave, Cambridge, MA 02139, USA.
 *
 *
 * Reference:
 *	1. SiS 630 Specification
 *	2. SiS 950 Specification
 *
 * $Id: flash_rom.c,v 1.21 2005/01/11 02:48:22 ollie Exp $
 */

#include <errno.h>
#include <fcntl.h>
#include <sys/mman.h>
#include <unistd.h>
#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#define UADDR1 0xAAA
#define UADDR2 0x554

int main(int argc, char *argv[])
{
	int fd_mem, fd_flash, i, i2;
	volatile unsigned short *bios, flash;
	unsigned long off,valint;
	unsigned short val, wrote;

	if ((fd_mem = open("/dev/mem", O_RDWR)) < 0) {
		perror("Can not open /dev/mem");
		exit(1);
	}

	if ((fd_flash = open("flash.rom", O_RDONLY)) < 0) {
		perror("Can not open flash.rom");
		exit(1);
	}

	bios = mmap((void *)0x70000000, 0x20000, PROT_WRITE | PROT_READ, MAP_SHARED,
		    fd_mem, (off_t) (0x70000000));
	if (bios == MAP_FAILED) {
		perror("Error MMAP /dev/mem");
		exit(1);
	}

	/* Enter unlock bypass mode */
	bios[UADDR1] = 0xf0;
	//msync((void *)bios, 0x20000, MS_SYNC);

	i=0;
	while (read(fd_flash, (void *)&flash, 2) == 2) {
		if ((bios[i] == 0xffff) && (flash != 0xffff)) {
		  wrote = flash;
		  printf("Setting 0x%02x=0x%04x\n", i, wrote);
		  bios[UADDR1] = 0xAA;
		  //msync((void *)bios, 0x20000, MS_SYNC);
		  bios[UADDR2] = 0x55;
		  //msync((void *)bios, 0x20000, MS_SYNC);
		  bios[UADDR1] = 0xA0;
		  //msync((void *)bios, 0x20000, MS_SYNC);
		  bios[i] = wrote;
		  msync((void *)bios, 0x20000, MS_SYNC);
		  //i2=0x1000;
		  //while(i2-- > 0);
		  i2=0x1000000;
		  while((bios[i] != wrote) && (i2-- > 0));
		  if (bios[i] != wrote) {
			printf("Error writing at %x (%x)\n", i, bios[i]);
		  	//bios[UADDR1] = 0xf0;
		  }
		  bios[UADDR1] = 0xAA;
		  bios[UADDR2] = 0x55;
		  bios[UADDR1] = 0xf0;
		 msync((void *)bios, 0x20000, MS_SYNC);
		  //msync((void *)bios, 0x20000, MS_SYNC);
		  //printf("0x%02x=0x%04x\n", i, bios[i]);
		}
		i++;
	}

	bios[UADDR1] = 0xf0;

	munmap((void *) bios, 0x20000);
	return 0;
}