Re: Bug in MTD NAND ONFI chipsize detection

From: Nitin Garg
Date: Thu May 12 2011 - 11:19:49 EST


I hope this is better and acceptable, pls review.

As per ONFI standard, the size of NAND Flash device is Number of
data bytes per page * Number of pages per block * Number of blocks
per logical unit * Number of logical units. The nand_flash_detect_onfi
function is missing the Number of logical units due to which the kernel
detects wrong size of Micron MT29F8G08ADADAH4 NAND Flash as
it has 2 logical units. This patch fixes this issue by multiplying
p->lun_count for chipsize.

Signed-off-by: Nitin Garg <nitingarg98@xxxxxxxxx>
---
drivers/mtd/nand/nand_base.c | 2 +-
1 files changed, 1 insertions(+), 1 deletions(-)

diff --git a/drivers/mtd/nand/nand_base.c b/drivers/mtd/nand/nand_base.c
index c54a4cb..cdf6015 100644
--- a/drivers/mtd/nand/nand_base.c
+++ b/drivers/mtd/nand/nand_base.c
@@ -2892,7 +2892,7 @@ static int nand_flash_detect_onfi(struct
mtd_info *mtd, struct nand_chip *chip,
mtd->writesize = le32_to_cpu(p->byte_per_page);
mtd->erasesize = le32_to_cpu(p->pages_per_block) * mtd->writesize;
mtd->oobsize = le16_to_cpu(p->spare_bytes_per_page);
- chip->chipsize = (uint64_t)le32_to_cpu(p->blocks_per_lun) *
mtd->erasesize;
+ chip->chipsize = (uint64_t)le32_to_cpu(p->blocks_per_lun) *
le32_to_cpu(p->lun_count) * mtd->erasesize;
busw = 0;
if (le16_to_cpu(p->features) & 1)
busw = NAND_BUSWIDTH_16;
--
1.5.5.6

Attachment: onfi_nand_flash_chipsize.patch
Description: Binary data