From c312e183e96bed3b727888673d4b6b54b8e6283e Mon Sep 17 00:00:00 2001 From: Brian Norris Date: Thu, 14 Nov 2013 14:41:32 -0800 Subject: [PATCH 154/203] mtd: nand: pxa3xx: make ECC configuration checks more explicit The Armada BCH configuration in this driver uses one of the two following ECC schemes: 16-bit correction per 2048 bytes 16-bit correction per 1024 bytes These are sufficient for mapping to the 4-bit per 512-bytes and 8-bit per 512-bytes (respectively) minimum correctability requirements of many common NAND. The current code only checks for the required strength (4-bit or 8-bit) without checking the ECC step size that is associated with that strength (and simply assumes it is 512). While that is often a safe assumption to make, let's make it explicit, since we have that information. Signed-off-by: Brian Norris Acked-by: Ezequiel Garcia Tested-by: Daniel Mack --- drivers/mtd/nand/pxa3xx_nand.c | 15 ++++++++++++--- 1 file changed, 12 insertions(+), 3 deletions(-) --- a/drivers/mtd/nand/pxa3xx_nand.c +++ b/drivers/mtd/nand/pxa3xx_nand.c @@ -1364,9 +1364,13 @@ static int pxa_ecc_init(struct pxa3xx_na static int armada370_ecc_init(struct pxa3xx_nand_info *info, struct nand_ecc_ctrl *ecc, - int strength, int page_size) + int strength, int ecc_stepsize, int page_size) { - if (strength == 4 && page_size == 4096) { + /* + * Required ECC: 4-bit correction per 512 bytes + * Select: 16-bit correction per 2048 bytes + */ + if (strength == 4 && ecc_stepsize == 512 && page_size == 4096) { info->ecc_bch = 1; info->chunk_size = 2048; info->spare_size = 32; @@ -1377,7 +1381,11 @@ static int armada370_ecc_init(struct pxa ecc->strength = 16; return 1; - } else if (strength == 8 && page_size == 4096) { + /* + * Required ECC: 8-bit correction per 512 bytes + * Select: 16-bit correction per 1024 bytes + */ + } else if (strength == 8 && ecc_stepsize == 512 && page_size == 4096) { info->ecc_bch = 1; info->chunk_size = 1024; info->spare_size = 0; @@ -1485,6 +1493,7 @@ KEEP_CONFIG: if (info->variant == PXA3XX_NAND_VARIANT_ARMADA370) ret = armada370_ecc_init(info, &chip->ecc, chip->ecc_strength_ds, + chip->ecc_step_ds, mtd->writesize); else ret = pxa_ecc_init(info, &chip->ecc,