sysmo-bts
/
barebox
9
0
Fork 0
Code Releases Activity

nand: mxs: Fix for calculating ecc strength on some types of NAND flash 

Was tested on NAND with {writesize=4096, oobsize=224} and
{writesize=2048, oobsize=64}.

This patch will not break any NAND that was working
before. Implemented calculation way may be used for other NAND chips
with writesize == 2048 but oobsize != 64.

Signed-off-by: Dmitry Lavnikevich <d.lavnikevich@sam-solutions.com>
Signed-off-by: Grigory Milev <g.milev@sam-solutions.com>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
This commit is contained in:
Dmitry Lavnikevich 2014-03-10 14:39:53 +03:00 committed by Sascha Hauer
parent c15680099e
commit 3676454f5c
1 changed files with 17 additions and 4 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

21
drivers/mtd/nand/nand_mxs.c
View File

@ -234,18 +234,31 @@ 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)
{
int ecc_chunk_count = mxs_nand_ecc_chunk_cnt(page_data_size);
int ecc_strength = 0;
int gf_len = 13; /* length of Galois Field for non-DDR nand */
/*
* Possibly this if-else calculation may be removed since
* ecc_strength calculated after it is taken from kernel driver
* and therefore should work for all cases. But it was tested only
* on devices with {data_size = 2046, oob_size = 64} and
* {data_size = 4096, oob_size = 224} configuration.
*/
if (page_data_size == 2048)
return 8;
if (page_data_size == 4096) {
else if (page_data_size == 4096) {
if (page_oob_size == 128)
return 8;
if (page_oob_size == 218)
return 16;
}
return 0;
ecc_strength = ((page_oob_size - MXS_NAND_METADATA_SIZE) * 8)
/ (gf_len * ecc_chunk_count);
/* We need the minor even number. */
return rounddown(ecc_strength, 2);
}
static inline uint32_t mxs_nand_get_mark_offset(uint32_t page_data_size,