From: Peng Fan Peng.Fan@freescale.com
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 Reviewed-by: Marek Vasut marex@denx.de Signed-off-by: Jörg Krause joerg.krause@embedded.rocks --- Changes for v3: - squashed "[U-Boot,v2,3/4] mtd: nand: mxs: Add comment for calculating ECC strength" https://patchwork.ozlabs.org/patch/460926/ - Coding Style cleanup Changes for v2: - None (original patch from Peng Fan) --- drivers/mtd/nand/mxs_nand.c | 30 ++++++++++++------------------ 1 file changed, 12 insertions(+), 18 deletions(-)
diff --git a/drivers/mtd/nand/mxs_nand.c b/drivers/mtd/nand/mxs_nand.c index 7a064ab..a463de7 100644 --- a/drivers/mtd/nand/mxs_nand.c +++ b/drivers/mtd/nand/mxs_nand.c @@ -146,26 +146,20 @@ 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; - - if (page_oob_size == 224) - return 16; - } + /* + * Determine the ECC layout with the formula: + * ECC bits per chunk = (total page spare data bits) / + * (bits per ECC level) / (chunks per page) + * where: + * total page spare data bits = + * (page oob size - meta data size) * (bits per byte) + */ + ecc_strength = ((page_oob_size - MXS_NAND_METADATA_SIZE) * 8) + / (13 * mxs_nand_ecc_chunk_cnt(page_data_size));
- return 0; + return round_down(ecc_strength, 2); }
static inline uint32_t mxs_nand_get_mark_offset(uint32_t page_data_size,