srecord.c

MIPS处理器的bootloader,龙芯就是用的修改过的PMON2

/*
 * convert binary file to Srecord format
 */

#include <stdio.h>
#include <ctype.h>

static int get32();
static void put32();
static void sput();
static void put();
static int checksum();
int    mask;
int    size;

main(argc, argv)
int	argc;
char	*argv[];
{
char	buf[32];
int	cc;
int	base;
int	addr;
char	*name;

	if( argc != 4 ) {
		fprintf(stderr, "usage: %s {size} {hex_addr} {name}\n", argv[0]);
		fprintf(stderr, "Size = 2, 3, or 4 byte address\n");
		exit(1);
	}
	sscanf(argv[1], "%x", &size);
	mask = (1 << (size *8))-1;
	if (!mask) mask = (-1);
	sscanf(argv[2], "%x", &base);
	name = argv[3];

	if (size==2) printf("S0%02X%04X", 2 + strlen(name) + 1, 0);
	if (size==3) printf("S0%02X%06X", 3 + strlen(name) + 1, 0);
	if (size==4) printf("S0%02X%08X", 4 + strlen(name) + 1, 0);
	sput(name);
	printf("%02X\n", checksum(0, name, strlen(name),size));

	addr = base;
	for( ;; ) {
		cc = get32(buf);
		if( cc > 0 ) {
			put32(cc, addr, buf,size,mask);
			addr += cc;
		} else
			break;
	}

	buf[0] = base >> 8;
	buf[1] = base;
	printf("S%d%02X",11-size,2 + 1);
	switch (size) {
	    case 2: printf("%04X", base & mask); break;
	    case 3: printf("%06X", base & mask); break;
	    case 4: printf("%08X", base & mask); break;
	}
/* kludge -> don't know why you have to add the +1 = works for size =3 at least */
	printf("%02X\n",checksum(base, (char *)0, 0, size)+1);
}


static int
get32(buf)
char	buf[];
{
char	*cp = buf;
int	i;
int	c;

	for( i = 0; i < 32 ; ++i ) {
		if( (c = getchar()) != EOF )
			*cp++ = c;
		else
			break;
	}
	return cp - buf;
}


static void
put32(len, addr, buf,size,mask)
int	len;
int	addr;
char	buf[];
int	size,mask;
{
char	*cp = buf;
int	i;

	if (size ==2) printf("S1%02X%04X", 2 + len + 1, addr & mask);
	if (size ==3) printf("S2%02X%06X", 3 + len + 1, addr & mask);
	if (size ==4) printf("S3%02X%08X", 4 + len + 1, addr & mask);
	for( i = 0; i < len ; ++i )
		put(*cp++);
	printf("%02X\n", checksum(addr, buf, len,size));
}


static void
sput(s)
char	*s;
{
	while( *s != '\0' )
		put(*s++);
}


static void
put(c)
int c;
{
	printf("%02X", c & 0xff);
}


static int
checksum(addr, buf, len,size)
int	addr;
char	buf[];
int	len;
int	size;
{
char	*cp = buf;
int	sum = 0xff - 1 - size - (len & 0xff);
int	i;

	if (size ==4) sum -= (addr >>24) & 0xff;
	if (size >=3) sum -= (addr >>16) & 0xff;
	sum -= (addr >> 8) & 0xff;
	sum -= addr & 0xff;
	for( i = 0; i < len ; ++i ) {
		sum -= *cp++ & 0xff;
	}
	return sum & 0xff;
}