在使用tftp下载内核时,使用tftp 0x32000000 uImage,然后使用nand的命令将uImage写入nandflash中发现一个比较奇异的错误提示:10384bytes write error,通过调试发现,在校验函数nand_verify_pages中校验写入内容出错,通过分析代码,发现在写每块的page的时候出错,修改代码,在1680行添加this->data_poi = (u_char*) &buf[written];问题解决。
nand_write_ecc函数代码:
/**
* nand_write_ecc - [MTD Interface] NAND write with ECC
* @mtd: MTD device structure
* @to: offset to write to
* @len: number of bytes to write
* @retlen: pointer to variable to store the number of written bytes
* @buf: the data to write
* @eccbuf: filesystem supplied oob data buffer
* @oobsel: oob selection structure
*
* NAND write with ECC
*/
static int nand_write_ecc (struct mtd_info *mtd, loff_t to, size_t len,
size_t * retlen, const u_char * buf, u_char * eccbuf, struct nand_oobinfo *oobsel)
{
int startpage, page, ret = -EIO, oob = 0, written = 0, chipnr;
int autoplace = 0, numpages, totalpages;
struct nand_chip *this = mtd->priv;
u_char *oobbuf, *bufstart;
int ppblock = (1 << (this->phys_erase_shift - this->page_shift));
DEBUG (MTD_DEBUG_LEVEL3, "nand_write_ecc: to = 0x%08x, len = %i\n", (unsigned int) to, (int) len);
/* Initialize retlen, in case of early exit */
*retlen = 0;
/* Do not allow write past end of device */
if ((to + len) > mtd->size) {
DEBUG (MTD_DEBUG_LEVEL0, "nand_write_ecc: Attempt to write past end of page\n");
return -EINVAL;
}
/* reject writes, which are not page aligned */
if (NOTALIGNED (to) || NOTALIGNED(len)) {
printk (KERN_NOTICE "nand_write_ecc: Attempt to write not page aligned data\n");
return -EINVAL;
}
/* Grab the lock and see if the device is available */
nand_get_device (this, mtd, FL_WRITING);
/* Calculate chipnr */
chipnr = (int)(to >> this->chip_shift);
/* Select the NAND device */
this->select_chip(mtd, chipnr);
/* Check, if it is write protected */
if (nand_check_wp(mtd))
goto out;
/* if oobsel is NULL, use chip defaults */
if (oobsel == NULL)
oobsel = &mtd->oobinfo;
/* Autoplace of oob data ? Use the default placement scheme */
if (oobsel->useecc == MTD_NANDECC_AUTOPLACE) {
oobsel = this->autooob;
autoplace = 1;
}
if (oobsel->useecc == MTD_NANDECC_AUTOPL_USR)
autoplace = 1;
/* Setup variables and oob buffer */
totalpages = len >> this->page_shift;
page = (int) (to >> this->page_shift);
/* Invalidate the page cache, if we write to the cached page */
if (page <= this->pagebuf && this->pagebuf < (page + totalpages))
this->pagebuf = -1;
/* Set it relative to chip */
page &= this->pagemask;
startpage = page;
/* Calc number of pages we can write in one go */
numpages = min (ppblock - (startpage & (ppblock - 1)), totalpages);
oobbuf = nand_prepare_oobbuf (mtd, eccbuf, oobsel, autoplace, numpages);
bufstart = (u_char *)buf;
/* Loop until all data is written */
while (written < len) {
this->data_poi = (u_char*) &buf[written];
/* Write one page. If this is the last page to write
* or the last page in this block, then use the
* real pageprogram command, else select cached programming
* if supported by the chip.
*/
ret = nand_write_page (mtd, this, page, &oobbuf[oob], oobsel, (--numpages > 0));
if (ret) {
DEBUG (MTD_DEBUG_LEVEL0, "nand_write_ecc: write_page failed %d\n", ret);
goto out;
}
/* Next oob page */
oob += mtd->oobsize;
/* Update written bytes count */
written += mtd->oobblock;
if (written == len)
goto cmp;
/* Increment page address */
page++;
/* Have we hit a block boundary ? Then we have to verify and
* if verify is ok, we have to setup the oob buffer for
* the next pages.
*/
if (!(page & (ppblock - 1))){
int ofs;
this->data_poi = bufstart;
ret = nand_verify_pages (mtd, this, startpage,
page - startpage,
oobbuf, oobsel, chipnr, (eccbuf != NULL));
if (ret) {
DEBUG (MTD_DEBUG_LEVEL0, "nand_write_ecc: verify_pages failed %d\n", ret);
goto out;
}
*retlen = written;
bufstart = (u_char*) &buf[written];
ofs = autoplace ? mtd->oobavail : mtd->oobsize;
if (eccbuf)
eccbuf += (page - startpage) * ofs;
totalpages -= page - startpage;
numpages = min (totalpages, ppblock);
page &= this->pagemask;
startpage = page;
oob = 0;
this->oobdirty = 1;
oobbuf = nand_prepare_oobbuf (mtd, eccbuf, oobsel,
autoplace, numpages);
/* Check, if we cross a chip boundary */
if (!page) {
chipnr++;
this->select_chip(mtd, -1);
this->select_chip(mtd, chipnr);
}
}
}
/* Verify the remaining pages */
cmp:
this->data_poi = bufstart;
ret = nand_verify_pages (mtd, this, startpage, totalpages,
oobbuf, oobsel, chipnr, (eccbuf != NULL));
if (!ret)
*retlen = written;
else
DEBUG (MTD_DEBUG_LEVEL0, "nand_write_ecc: verify_pages failed %d\n", ret);
out:
/* Deselect and wake up anyone waiting on the device */
nand_release_device(mtd);
return ret;
}