From f693b6485e251ddf849d862cf6406a4dfc0143b3 Mon Sep 17 00:00:00 2001 From: Amit Kumar Mahapatra Date: Wed, 27 Sep 2023 11:26:21 +0530 Subject: [PATCH] mtd: rawnand: arasan: Include ECC syndrome along with in-band data while checking for ECC failure Following an ECC failure condition upon page reads, we shall distinguish between a real ECC failure and an empty page. This is handled with a call to nand_check_erased_ecc_chunk() which looks at the data and counts the number of bits which are not 'ones'. If we get less zeros than the ECC strength, we assume the page was erased and we are in the presence of natural bitflips. Otherwise, if we are above, we assume some data was written and the ECC engine could not recover it all, so we report an ECC failure. In order for this logic to be as close as the reality as we can (this is already a simplified condition but we can hardly be more precise), we should check all the data that is covered by the ECC step not only the in-band data, so we should also include the ECC syndrome in the check. Fixes: 88ffef1b65cf ("mtd: rawnand: arasan: Support the hardware BCH ECC engine") Signed-off-by: Amit Kumar Mahapatra Signed-off-by: Miquel Raynal Link: https://lore.kernel.org/linux-mtd/20230927055621.2906454-1-amit.kumar-mahapatra@amd.com --- drivers/mtd/nand/raw/arasan-nand-controller.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/mtd/nand/raw/arasan-nand-controller.c b/drivers/mtd/nand/raw/arasan-nand-controller.c index 4621ec549cc79..547cc82b5d809 100644 --- a/drivers/mtd/nand/raw/arasan-nand-controller.c +++ b/drivers/mtd/nand/raw/arasan-nand-controller.c @@ -481,7 +481,7 @@ static int anfc_read_page_hw_ecc(struct nand_chip *chip, u8 *buf, } bf = nand_check_erased_ecc_chunk(raw_buf, chip->ecc.size, - NULL, 0, NULL, 0, + anand->hw_ecc, chip->ecc.bytes, NULL, 0, chip->ecc.strength); if (bf > 0) { mtd->ecc_stats.corrected += bf; -- 2.30.2