On Fr, 2014-12-19 at 12:39 +0800, Peng Fan wrote:
Calculate ecc strength according oobsize, but not hardcoded which is not aligned with kernel driver
Signed-off-by: Peng Fan Peng.Fan@freescale.com Signed-off-by: Ye.Li b37916@freescale.com
drivers/mtd/nand/mxs_nand.c | 22 ++++------------------ 1 file changed, 4 insertions(+), 18 deletions(-)
diff --git a/drivers/mtd/nand/mxs_nand.c b/drivers/mtd/nand/mxs_nand.c index 7a064ab..a45fcf9 100644 --- a/drivers/mtd/nand/mxs_nand.c +++ b/drivers/mtd/nand/mxs_nand.c @@ -146,26 +146,12 @@ static uint32_t mxs_nand_aux_status_offset(void) static inline uint32_t mxs_nand_get_ecc_strength(uint32_t page_data_size, uint32_t page_oob_size) {
- if (page_data_size == 2048) {
if (page_oob_size == 64)return 8;
- int ecc_strength;
if (page_oob_size == 112)return 14;- }
- if (page_data_size == 4096) {
if (page_oob_size == 128)return 8;if (page_oob_size == 218)return 16;
- ecc_strength = ((page_oob_size - MXS_NAND_METADATA_SIZE) * 8)
/ (13 * mxs_nand_ecc_chunk_cnt(page_data_size));
if (page_oob_size == 224)return 16;- }
- return 0;
- return round_down(ecc_strength, 2);
}
static inline uint32_t mxs_nand_get_mark_offset(uint32_t page_data_size,
Many thanks for the patch! But this patch affects mxsboot which is no not aligned with the U-Boot mxs nand driver.
I was able to fix mxsboot, but I had difficulties with round_down, which is a macro definition in linux/kernel.h. I've copied the macro definition to mxsboot. I will submit the patch in a seperate mail.
I would like to see a comment or a macro for the magic number 13, which is the value for the Galois Field, just for clarification
With fixing mxsboot, I was able to test the patch on a custom i.MX28-based board assembled with a 1Gbit NAND flash (page size = 2048 bytes, oob size = 128 bytes).
U-Boot correctly reads the NAND info => nand info Device 0: nand0, sector size 128 KiB Page size 2048 b OOB size 128 b Erase size 131072 b
Before the patch linux failed to read from the UBI device with an ECC error: UBI error: ubi_io_read: error -74 (ECC error)
This patch resolves the error. Linux can read the UBI device now. This is kernel message: nand: device found, Manufacturer ID: 0x98, Chip ID: 0xf1 [ 1.327810] nand: Toshiba NAND 128MiB 3,3V 8-bit [ 1.332482] nand: 128MiB, SLC, page size: 2048, OOB size: 128 BCH Geometry : [ 1.594658] GF length : 13 [ 1.594658] ECC Strength : 18 [ 1.594658] Page Size in Bytes : 2176 [ 1.594658] Metadata Size in Bytes : 10 [ 1.594658] ECC Chunk Size in Bytes: 512 [ 1.594658] ECC Chunk Count : 4 [ 1.594658] Payload Size in Bytes : 2048 [ 1.594658] Auxiliary Size in Bytes: 16 [ 1.594658] Auxiliary Status Offset: 12 [ 1.594658] Block Mark Byte Offset : 1950 [ 1.594658] Block Mark Bit Offset : 2