使用mtd-utils工具实现对flash的升级分区的烧写yaffs2
yaffs2的格式是根据所使用的nandflash来制作的，不同的nandflash，得到的yaffs2是不一样的，具体可以参考自己所用的nandflash，以及生成yaffs2文件系统的工具mkyaffs2image。
yaffs2包含了oob数据，所以写flash的时候要分开，本文所使用的是256M oob是64bit，page是2048byte-2kByte，block=64page制作的yaffs2的大小是（2048+64）的倍数！
每次写入是按页（page）的大小写入，而擦除是按照块来的，坏块也是按照块来的，如果当前块是坏的就必须跳过该块！
下载mtd-utils源码！
yaffs2的写入函数
int mtd_write_yaffs2_skip_bad(libmtd_t desc,const struct mtd_dev_info *mtd, int fd, int eb, int offs,
const char *img_name)函数用来烧写flash，如下：
{
int tmp, ret, in_fd, len, written = ;
int write_eb_num,i;
int data_length,left_to_write,writesize;
off_t seek;
struct stat st;
char *buf,*temp,*dataAddr,*oobAddr; if (offs < || offs >= mtd->eb_size) {
errmsg("bad offset %d, mtd%d eraseblock size is %d",
offs, mtd->mtd_num, mtd->eb_size);
errno = EINVAL;
return -;
}
if (offs % mtd->subpage_size) {
//start address must align to page (2048)0x800
errmsg("write offset %d is not aligned to mtd%d min. I/O size %d",
offs, mtd->mtd_num, mtd->subpage_size);
errno = EINVAL;
return -;
}
in_fd = open(img_name, O_RDONLY | O_CLOEXEC);
if (in_fd == -)
return sys_errmsg("cannot open \"%s\"", img_name); if (fstat(in_fd, &st)){
sys_errmsg("cannot stat %s", img_name);
goto out_close;
} len = st.st_size;
if (len % (mtd->subpage_size + mtd->oob_size)){
errmsg("size of \"%s\" is %d byte, which is not aligned to "
"mtd%d min. I/O size %d, it is not a yaffs2 file ", img_name, len, mtd->mtd_num,
mtd->subpage_size + mtd->oob_size);
errno = EINVAL;
goto out_close;
}
data_length = len / (mtd->subpage_size + mtd->oob_size) * mtd->subpage_size; tmp = (offs + data_length + mtd->eb_size - ) / mtd->eb_size;
if (eb + tmp > mtd->eb_cnt) {
errmsg("\"%s\" image size(except oob size) is %d bytes, mtd%d size is %d "
"eraseblocks, the image does not fit if we write it "
"starting from eraseblock %d, offset %d",
img_name, data_length, mtd->mtd_num, mtd->eb_cnt, eb, offs);
errno = EINVAL;
goto out_close;
} /* Seek to the beginning of the eraseblock */
seek = (off_t)eb * mtd->eb_size + offs;
if (lseek(fd, seek, SEEK_SET) != seek) {
sys_errmsg("cannot seek mtd%d to offset %llu",
mtd->mtd_num, (unsigned long long)seek);
goto out_close;
}
writesize = (mtd->eb_size / mtd->subpage_size) *( mtd->subpage_size + mtd->oob_size);
printf("write size with oob size is: %d \n",writesize);
buf = xmalloc(writesize); left_to_write = len;
write_eb_num = eb;
///writeoffs = eb*mtd->eb_size + offs; while (left_to_write > ) {
int rd = ; ret = mtd_is_bad(mtd,fd,write_eb_num);//判断当前块是否是坏块！
if(ret >){ //是坏块！
write_eb_num = write_eb_num + ;
if(write_eb_num >= mtd->eb_cnt)
{
if(left_to_write < ){
goto out_free;
}
}
else {
printf("skip bad blocks at offset: %d \n",write_eb_num);
continue;
}
}else if(ret <){
printf("get bad blocks error: %d\n",errno);
} if(left_to_write < (mtd->eb_size +mtd->oob_size)){
writesize = left_to_write;
}
else{
writesize = (mtd->eb_size / mtd->subpage_size) *( mtd->subpage_size + mtd->oob_size);
} ret = read(in_fd, buf, writesize);
if(ret == -) {
sys_errmsg("cannot read \"%s\"", img_name);
goto out_free;
} temp = buf; dataAddr = temp;
oobAddr = temp + mtd->subpage_size; for(i=;i< mtd->eb_size/mtd->subpage_size;i++){ //完成一个块的写入！
ret = mtd_write(desc,mtd,fd,write_eb_num,i*mtd->subpage_size,dataAddr,mtd->subpage_size,oobAddr,mtd->oob_size,MTD_OPS_RAW);
if(ret < ){
printf("write data witd oob error : %d \n",errno);
}
temp = oobAddr + mtd->oob_size;
dataAddr = temp;
oobAddr = temp + mtd->subpage_size;
}
write_eb_num = write_eb_num +;
left_to_write -= writesize;
printf("left_to_write :%d write_eb_num: %d,writesize:%d\n",left_to_write,write_eb_num,writesize); } free(buf);
close(in_fd);
return ; out_free:
free(buf);
out_close:
close(in_fd);
return -; }
yaffs2的读取函数
int mtd_read_yaffs2_skip_bad(libmtd_t desc,const struct mtd_dev_info *mtd, int fd, int eb, int offs,
const char *img_name)
{
int tmp, ret, out_fd, len, written = ;
int read_eb_num,i,sekOffs;
int data_length,left_to_read,readsize;
off_t seek;
struct stat st;
char *buf,*dataAddr,*oobAddr; if (offs < || offs >= mtd->eb_size) {
errmsg("bad offset %d, mtd%d eraseblock size is %d",
offs, mtd->mtd_num, mtd->eb_size);
errno = EINVAL;
return -;
}
if (offs % mtd->subpage_size) {
//start address must align to page (2048)0x800
errmsg("write offset %d is not aligned to mtd%d min. I/O size %d",
offs, mtd->mtd_num, mtd->subpage_size);
errno = EINVAL;
return -;
}
len = 0x193b3c0;//for test's length, you can read nand flash frome straddr to endaddr!!!
//also can read all mtdx device!
if (len % (mtd->subpage_size + mtd->oob_size)){
errmsg("size of \"%s\" is %d byte, which is not aligned to "
"mtd%d min. I/O size %d, it is not a yaffs2 file ", img_name, len, mtd->mtd_num,
mtd->subpage_size + mtd->oob_size);
errno = EINVAL;
goto out_close;
}
data_length = len / (mtd->subpage_size + mtd->oob_size) * mtd->subpage_size; tmp = (offs + data_length + mtd->eb_size - ) / mtd->eb_size;
if (eb + tmp > mtd->eb_cnt) {
errmsg("\"%s\" image size(except oob size) is %d bytes, mtd%d size is %d "
"eraseblocks, the image does not fit if we write it "
"starting from eraseblock %d, offset %d",
img_name, data_length, mtd->mtd_num, mtd->eb_cnt, eb, offs);
errno = EINVAL;
goto out_close;
}
/* Seek to the beginning of the eraseblock */
seek = (off_t)eb * mtd->eb_size + offs;
if (lseek(fd, seek, SEEK_SET) != seek) {
sys_errmsg("cannot seek mtd%d to offset %llu",
mtd->mtd_num, (unsigned long long)seek);
goto out_close;
} readsize = mtd->subpage_size + mtd->oob_size;
printf("read size with oob size is: %d \n",readsize); buf = xmalloc(readsize); dataAddr = buf;
oobAddr = buf + mtd->subpage_size; left_to_read = len;
read_eb_num = eb; out_fd = open(img_name,O_WRONLY|O_CREAT|O_TRUNC|O_APPEND, S_IRUSR | S_IWUSR);
if(out_fd < ){
printf("open write file error: %d \n",errno);
return -;
} while (left_to_read > ) {
int rd = ; ret = mtd_is_bad(mtd,fd,read_eb_num);
if(ret >){
read_eb_num = read_eb_num + ;
if(read_eb_num >= mtd->eb_cnt)
{
if(left_to_read < ){
goto out_free;
}
}
else {
printf("skip bad blocks at offset: %d \n",read_eb_num);
continue;
}
}else if(ret <){
printf("get bad blocks error: %d\n",errno);
} if(left_to_read < (mtd->eb_size +mtd->oob_size)){
readsize = left_to_read;
}
else{
readsize = (mtd->eb_size / mtd->subpage_size) *( mtd->subpage_size + mtd->oob_size);
} for(i=;i< mtd->eb_size/mtd->subpage_size;i++){ ret = mtd_read(mtd,fd,read_eb_num,i*mtd->subpage_size,dataAddr,mtd->subpage_size);
if(ret < ){
printf("read data error: %d \n",errno);
goto out_free;
} sekOffs = read_eb_num * mtd->eb_size + i*mtd->subpage_size;
seek = (off_t)sekOffs;
//printf("seek %#llx sek offs %#x \n",seek,sekOffs);
ret = mtd_read_oob(desc,mtd,fd,seek,mtd->oob_size,oobAddr);
if(ret < ){
printf("read oob error: %d \n",errno);
goto out_free;
} ret = write(out_fd, dataAddr, mtd->subpage_size);
if(ret == -) {
sys_errmsg("cannot write data \"%s\"", img_name);
goto out_free;
}
ret = write(out_fd, oobAddr, mtd->oob_size);
if(ret == -) {
sys_errmsg("cannot write oob \"%s\"", img_name);
goto out_free;
}
}
read_eb_num = read_eb_num +;
left_to_read -= readsize;
printf("left_to_read :%-7d write_eb_num: %-3d,readsize:%-6d\n",left_to_read,read_eb_num,readsize);
}
free(buf);
close(out_fd);
return ;
out_free:
free(buf);
out_close:
close(out_fd);
return -; }
测试烧写；
具体如下：
int mtdDevFd1 =,ret =,i;
libmtd_t mtd_desc;
char* image_file = FILE_NAME;
struct mtd_dev_info mtd;
//open mtd device, see it at /dev/mtdX
//get mtd message : cat /proc/mtd
if ((mtdDevFd1 = open(mtdDev1, O_RDWR)) < ){
_SEND_DBUG_MSG("open %s error \n",mtdDev2);
ret =-;
goto out_close;
}
mtd_desc = libmtd_open();
if(mtd_desc == NULL){
_SEND_DBUG_MSG("can not initlize mtd lib \n");
ret =-;
goto out_close;
} if (mtd_get_dev_info(mtd_desc,mtdDev1,&mtd) < ){
ret =-;
goto out_close;;
_SEND_DBUG_MSG("get dev info error!\n");
}
printf("size:%#x \n",mtd.size);
printf("eb_size:%#x \n",mtd.eb_size);
printf("name:%s \n",mtd.name);
printf("subpage size: %#x \n",mtd.subpage_size);
printf("oob size: %#x \n",mtd.oob_size);
printf("eb_cnt: %#x \n",mtd.eb_cnt); for(i = ; i< mtd.eb_cnt;i++){
if(mtd_is_bad(&mtd, mtdDevFd1, i))
{
printf("erase skip bad block num: %d \n",i);
continue;
}
if( != mtd_erase(mtd_desc,&mtd,mtdDevFd1,i)){//擦除！
_SEND_DBUG_MSG("ersae error \n");
ret =-;
goto out_close;
}
}
if( != mtd_write_yaffs2_skip_bad(mtd_desc,&mtd,mtdDevFd1,,,image_file)){
_SEND_DBUG_MSG("write yaffs2 error \n");
ret = -;
}
out_close:
libmtd_close(mtd_desc);
close(mtdDevFd1);
//write end!!!