blob: 111318ddb1722ef2ac59c3cca7ea0d646b8910a9 [file] [log] [blame] [edit]
/*
* flash_otp_write.c -- write One-Time-Program data
*/
#define PROGRAM_NAME "flash_otp_write"
#include <stdio.h>
#include <unistd.h>
#include <fcntl.h>
#include <string.h>
#include <stdlib.h>
#include <errno.h>
#include <sys/types.h>
#include <sys/ioctl.h>
#include <common.h>
#include <mtd/mtd-user.h>
ssize_t xread(int fd, void *buf, size_t count)
{
ssize_t ret, done = 0;
retry:
ret = read(fd, buf + done, count - done);
if (ret < 0)
return ret;
done += ret;
if (ret == 0 /* EOF */ || done == count)
return done;
else
goto retry;
}
int main(int argc,char *argv[])
{
int fd, val, ret, size, wrote, len;
mtd_info_t mtdInfo;
off_t offset;
char *p, buf[2048];
if (argc != 4 || strcmp(argv[1], "-u")) {
fprintf(stderr, "Usage: %s -u <device> <offset>\n", PROGRAM_NAME);
fprintf(stderr, "the raw data to write should be provided on stdin\n");
fprintf(stderr, "CAUTION! ONCE SET TO 0, OTP DATA BITS CAN'T BE ERASED!\n");
return EINVAL;
}
fd = open(argv[2], O_WRONLY);
if (fd < 0) {
perror(argv[2]);
return errno;
}
val = MTD_OTP_USER;
ret = ioctl(fd, OTPSELECT, &val);
if (ret < 0) {
perror("OTPSELECT");
return errno;
}
if (ioctl(fd, MEMGETINFO, &mtdInfo)) {
perror("MEMGETINFO");
return errno;
}
offset = (off_t)strtoull(argv[3], &p, 0);
if (argv[3][0] == 0 || *p != 0) {
fprintf(stderr, "%s: bad offset value\n", PROGRAM_NAME);
return ERANGE;
}
if (lseek(fd, offset, SEEK_SET) == (off_t)-1) {
perror("lseek()");
return errno;
}
printf("Writing OTP user data on %s at offset 0x%"PRIxoff_t"\n", argv[2], offset);
if (mtd_type_is_nand_user(&mtdInfo))
len = mtdInfo.writesize;
else
len = 256;
if (len > sizeof(buf)) {
printf("huh, writesize (%d) bigger than buffer (%zu)\n",
len, sizeof(buf));
return ENOMEM;
}
wrote = 0;
while ((size = xread(0, buf, len))) {
if (size < 0) {
perror("read()");
return errno;
}
p = buf;
while (size > 0) {
if (mtd_type_is_nand_user(&mtdInfo)) {
/* Fill remain buffers with 0xff */
memset(buf + size, 0xff, mtdInfo.writesize - size);
size = mtdInfo.writesize;
}
ret = write(fd, p, size);
if (ret < 0) {
perror("write()");
return errno;
}
if (ret == 0) {
printf("write() returned 0 after writing %d bytes\n", wrote);
return 0;
}
p += ret;
wrote += ret;
size -= ret;
}
}
printf("Wrote %d bytes of OTP user data\n", wrote);
return 0;
}