From: Boris Brezillon Date: Mon, 6 Jun 2016 11:59:12 +0000 (+0200) Subject: mtd: nand: sunxi: prefer 1k ECC blocks when applicable X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=872164e41fc8dee154e5f5d22580b34e198eed69;p=linux-beck.git mtd: nand: sunxi: prefer 1k ECC blocks when applicable Switching to 1k ECC blocks when possible provides better resistance against concentrated bitflips. Say you have those two configurations: 1/ 16bits/512bytes 2/ 32bits/1024bytes Both of them require the same amount of ECC bytes (only true for this specific engine), but the second config allows you to correct the case where most of your bitflips are concentrated in a single 512bytes portion. This fact makes the 1k ECC block size more advantageous than the 512bytes one. Signed-off-by: Boris Brezillon --- diff --git a/drivers/mtd/nand/sunxi_nand.c b/drivers/mtd/nand/sunxi_nand.c index b9a2e5d28754..bb440b91096f 100644 --- a/drivers/mtd/nand/sunxi_nand.c +++ b/drivers/mtd/nand/sunxi_nand.c @@ -1786,6 +1786,12 @@ static int sunxi_nand_hw_common_ecc_ctrl_init(struct mtd_info *mtd, if (!data) return -ENOMEM; + /* Prefer 1k ECC chunk over 512 ones */ + if (ecc->size == 512 && mtd->writesize > 512) { + ecc->size = 1024; + ecc->strength *= 2; + } + /* Add ECC info retrieval from DT */ for (i = 0; i < ARRAY_SIZE(strengths); i++) { if (ecc->strength <= strengths[i])