嵌入式Linux之我行——u-boot-2009.08在2440上的移植详解（五）

#gedit drivers/mtd/nand/nand_base.c//在nand_write函数中添加

static int nand_write(struct mtd_info *mtd, loff_t to, size_t len, size_t *retlen, const uint8_t *buf)
{
struct nand_chip *chip = mtd->priv;
int ret;

#if defined(CONFIG_MTD_NAND_YAFFS2)//add yaffs2 file system support

int oldopsmode = 0;

if(mtd->rw_oob==1)
{
int i = 0;
int datapages = 0;

size_t oobsize = mtd->oobsize;
size_t datasize = mtd->writesize;

uint8_t oobtemp[oobsize];
datapages = len / (datasize);

for(i = 0; i < (datapages); i++)
{
memcpy((void *)oobtemp, (void *)(buf + datasize * (i + 1)), oobsize);
memmove((void *)(buf + datasize * (i + 1)), (void *)(buf + datasize * (i + 1) + oobsize), (datapages - (i + 1)) * (datasize) + (datapages - 1) * oobsize);
memcpy((void *)(buf+(datapages) * (datasize + oobsize) - oobsize), (void *)(oobtemp), oobsize);
}
}
#endif

if ((to + len) > mtd->size)
return -EINVAL;
if (!len)
return 0;

nand_get_device(chip, mtd, FL_WRITING);

chip->ops.len = len;
chip->ops.datbuf = (uint8_t *)buf;

#if defined(CONFIG_MTD_NAND_YAFFS2)//add yaffs2 file system support

if(mtd->rw_oob!=1)
{
chip->ops.oobbuf = NULL;
}
else
{
chip->ops.oobbuf = (uint8_t *)(buf + len);
chip->ops.ooblen = mtd->oobsize;
oldopsmode = chip->ops.mode;
chip->ops.mode = MTD_OOB_RAW;
}
#else
chip->ops.oobbuf = NULL;
#endif

ret = nand_do_write_ops(mtd, to, &chip->ops);

*retlen = chip->ops.retlen;

nand_release_device(mtd);

#if defined(CONFIG_MTD_NAND_YAFFS2)//add yaffs2 file system support

chip->ops.mode = oldopsmode;
#endif

return ret;
}

tftp 0x30000000 root-2.6.30.4.bin//用tftp将yaffs2文件系统下载到内存的0x30000000位置

nand erase 0x250000 0x3dac000//擦除Nand的文件系统分区

nand write.yaffs2 0x30000000 0x250000 0x658170//将内存中的yaffs2文件系统写入Nand的文件系统分区，注意这里的0x658170是yaffs2文件系统的实际大小(可以在tftp传送完后可以看到)，要写正确，否则会形成假坏块