| Message ID | 1376906744-4711-1-git-send-email-josh.wu@atmel.com |
|---|---|
| State | Accepted |
| Commit | 2fa831f9db1f1a13960f4ea0fd0454402717b453 |
| Headers | show |
On Mon, 2013-08-19 at 18:05 +0800, Josh Wu wrote: > The PMECC use BCH algorithm to correct error. In BCH algorithm, the primitive > polynomial value is GF(2^13) for 512-bytes sector size. And it is GF(2^14) for > 1024-bytes sector size. > > This patch will choose correct degree of the remainders(13 or 14) for > different sector size. > Tested in AT91SAM9X5-EK with MLC nand flash. > > More detail can be refered to section 5.4.1 of: > AT91SAM ARM-based Embedded MPU Application Note > <http://www.atmel.com/Images/doc11127.pdf> > > Signed-off-by: Josh Wu <josh.wu@atmel.com> Pushed to l2-mtd.git, thanks!
diff --git a/drivers/mtd/nand/atmel_nand.c b/drivers/mtd/nand/atmel_nand.c index 0e365da..8b2eb3e 100644 --- a/drivers/mtd/nand/atmel_nand.c +++ b/drivers/mtd/nand/atmel_nand.c @@ -1204,7 +1204,8 @@ static int __init atmel_pmecc_nand_init_params(struct platform_device *pdev, /* set ECC page size and oob layout */ switch (mtd->writesize) { case 2048: - host->pmecc_degree = PMECC_GF_DIMENSION_13; + host->pmecc_degree = (sector_size == 512) ? + PMECC_GF_DIMENSION_13 : PMECC_GF_DIMENSION_14; host->pmecc_cw_len = (1 << host->pmecc_degree) - 1; host->pmecc_sector_number = mtd->writesize / sector_size; host->pmecc_bytes_per_sector = pmecc_get_ecc_bytes(
The PMECC use BCH algorithm to correct error. In BCH algorithm, the primitive polynomial value is GF(2^13) for 512-bytes sector size. And it is GF(2^14) for 1024-bytes sector size. This patch will choose correct degree of the remainders(13 or 14) for different sector size. Tested in AT91SAM9X5-EK with MLC nand flash. More detail can be refered to section 5.4.1 of: AT91SAM ARM-based Embedded MPU Application Note <http://www.atmel.com/Images/doc11127.pdf> Signed-off-by: Josh Wu <josh.wu@atmel.com> --- drivers/mtd/nand/atmel_nand.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-)