From d316cda736d011c8c3def9f8d07928e1ab6cdd72 Mon Sep 17 00:00:00 2001 From: Teresa Remmet Date: Mon, 11 Apr 2016 10:28:23 +0200 Subject: mtd: nand: omap_gpmc: Remove BCH4 support This has no users and seems to be untested. Removed it. Signed-off-by: Teresa Remmet Signed-off-by: Sascha Hauer --- arch/arm/mach-omap/include/mach/gpmc_nand.h | 1 - drivers/bus/omap-gpmc.c | 3 --- drivers/mtd/nand/nand_omap_gpmc.c | 36 +---------------------------- 3 files changed, 1 insertion(+), 39 deletions(-) diff --git a/arch/arm/mach-omap/include/mach/gpmc_nand.h b/arch/arm/mach-omap/include/mach/gpmc_nand.h index 8839486fcf..c9730a9454 100644 --- a/arch/arm/mach-omap/include/mach/gpmc_nand.h +++ b/arch/arm/mach-omap/include/mach/gpmc_nand.h @@ -32,7 +32,6 @@ enum gpmc_ecc_mode { OMAP_ECC_SOFT, OMAP_ECC_HAMMING_CODE_HW_ROMCODE, - OMAP_ECC_BCH4_CODE_HW, OMAP_ECC_BCH8_CODE_HW, OMAP_ECC_BCH8_CODE_HW_ROMCODE, }; diff --git a/drivers/bus/omap-gpmc.c b/drivers/bus/omap-gpmc.c index 8ae909a1b6..be9ef92851 100644 --- a/drivers/bus/omap-gpmc.c +++ b/drivers/bus/omap-gpmc.c @@ -445,9 +445,6 @@ static struct dt_eccmode modes[] = { }, { .name = "hw-romcode", .mode = OMAP_ECC_HAMMING_CODE_HW_ROMCODE, - }, { - .name = "bch4", - .mode = OMAP_ECC_BCH4_CODE_HW, }, { .name = "bch8", .mode = OMAP_ECC_BCH8_CODE_HW_ROMCODE, diff --git a/drivers/mtd/nand/nand_omap_gpmc.c b/drivers/mtd/nand/nand_omap_gpmc.c index a920522939..1d1de5b6fc 100644 --- a/drivers/mtd/nand/nand_omap_gpmc.c +++ b/drivers/mtd/nand/nand_omap_gpmc.c @@ -86,7 +86,6 @@ #define GPMC_ECC_SIZE_CONFIG_ECCSIZE1(x) ((x) << 22) #define BCH8_MAX_ERROR 8 /* upto 8 bit correctable */ -#define BCH4_MAX_ERROR 4 /* upto 4 bit correctable */ int omap_gpmc_decode_bch(int select_4_8, unsigned char *ecc, unsigned int *err_loc); @@ -239,9 +238,6 @@ static int __omap_calculate_ecc(struct mtd_info *mtd, const uint8_t *dat, int ecc_size = 8; switch (oinfo->ecc_mode) { - case OMAP_ECC_BCH4_CODE_HW: - ecc_size = 4; - /* fall through */ case OMAP_ECC_BCH8_CODE_HW: case OMAP_ECC_BCH8_CODE_HW_ROMCODE: for (i = 0; i < 4; i++) { @@ -300,24 +296,17 @@ static int omap_correct_bch(struct mtd_info *mtd, uint8_t *dat, struct gpmc_nand_info *oinfo = (struct gpmc_nand_info *)(nand->priv); int i, j, eccflag, count, totalcount, actual_eccsize; unsigned int err_loc[8]; - int select_4_8; int eccsteps = oinfo->nand.ecc.steps; int eccsize = oinfo->nand.ecc.bytes; switch (oinfo->ecc_mode) { - case OMAP_ECC_BCH4_CODE_HW: - actual_eccsize = eccsize; - select_4_8 = 0; - break; case OMAP_ECC_BCH8_CODE_HW: eccsize /= eccsteps; actual_eccsize = eccsize; - select_4_8 = 1; break; case OMAP_ECC_BCH8_CODE_HW_ROMCODE: actual_eccsize = eccsize - 1; - select_4_8 = 1; break; default: dev_err(oinfo->pdev, "invalid driver configuration\n"); @@ -344,7 +333,7 @@ static int omap_correct_bch(struct mtd_info *mtd, uint8_t *dat, count = 0; if (eccflag == 1) { - count = omap_gpmc_decode_bch(select_4_8, calc_ecc, err_loc); + count = omap_gpmc_decode_bch(1, calc_ecc, err_loc); if (count < 0) return count; else @@ -435,7 +424,6 @@ static int omap_correct_data(struct mtd_info *mtd, uint8_t *dat, switch (oinfo->ecc_mode) { case OMAP_ECC_HAMMING_CODE_HW_ROMCODE: return omap_correct_hamming(mtd, dat, read_ecc, calc_ecc); - case OMAP_ECC_BCH4_CODE_HW: case OMAP_ECC_BCH8_CODE_HW: case OMAP_ECC_BCH8_CODE_HW_ROMCODE: /* @@ -463,17 +451,6 @@ static void omap_enable_hwecc(struct mtd_info *mtd, int mode) int cs = 0; switch (oinfo->ecc_mode) { - case OMAP_ECC_BCH4_CODE_HW: - if (mode == NAND_ECC_READ) { - eccsize1 = 0xD; eccsize0 = 0x48; - bch_mod = 0; - bch_wrapmode = 0x09; - } else { - eccsize1 = 0x20; eccsize0 = 0x00; - bch_mod = 0; - bch_wrapmode = 0x06; - } - break; case OMAP_ECC_BCH8_CODE_HW: case OMAP_ECC_BCH8_CODE_HW_ROMCODE: if (mode == NAND_ECC_READ) { @@ -764,17 +741,6 @@ static int omap_gpmc_eccmode(struct gpmc_nand_info *oinfo, omap_oobinfo.oobfree->length = minfo->oobsize - offset - omap_oobinfo.eccbytes; break; - case OMAP_ECC_BCH4_CODE_HW: - oinfo->nand.ecc.bytes = 7; - oinfo->nand.ecc.size = 512; - oinfo->nand.ecc.strength = BCH4_MAX_ERROR; - omap_oobinfo.oobfree->offset = offset; - omap_oobinfo.oobfree->length = minfo->oobsize - - offset - omap_oobinfo.eccbytes; - offset = minfo->oobsize - oinfo->nand.ecc.bytes; - for (i = 0; i < oinfo->nand.ecc.bytes; i++) - omap_oobinfo.eccpos[i] = i + offset; - break; case OMAP_ECC_BCH8_CODE_HW: oinfo->nand.ecc.bytes = 13 * 4; oinfo->nand.ecc.size = 512 * 4; -- cgit v1.2.3 From 074f5cb1866fcf4db8d20d760ed018fe417fc9c5 Mon Sep 17 00:00:00 2001 From: Teresa Remmet Date: Mon, 11 Apr 2016 10:28:24 +0200 Subject: mtd: nand: omap_gpmc: Fix bitflips in empty page When using BCH8 decoding, bitflips in an empty page are not checked. This can cause issues if UBI/UBIFS are used. Extend the omap_correct_bch() function to check for them. Code is based on linux mainline mtd/nand/omap2.c driver. Signed-off-by: Teresa Remmet Signed-off-by: Sascha Hauer --- drivers/mtd/nand/nand_omap_gpmc.c | 62 ++++++++++++++++++++++++++------------- 1 file changed, 42 insertions(+), 20 deletions(-) diff --git a/drivers/mtd/nand/nand_omap_gpmc.c b/drivers/mtd/nand/nand_omap_gpmc.c index 1d1de5b6fc..a4e645201f 100644 --- a/drivers/mtd/nand/nand_omap_gpmc.c +++ b/drivers/mtd/nand/nand_omap_gpmc.c @@ -87,6 +87,9 @@ #define BCH8_MAX_ERROR 8 /* upto 8 bit correctable */ +static const uint8_t bch8_vector[] = {0xf3, 0xdb, 0x14, 0x16, 0x8b, 0xd2, + 0xbe, 0xcc, 0xac, 0x6b, 0xff, 0x99, 0x7b}; + int omap_gpmc_decode_bch(int select_4_8, unsigned char *ecc, unsigned int *err_loc); static const char *ecc_mode_strings[] = { @@ -294,8 +297,11 @@ static int omap_correct_bch(struct mtd_info *mtd, uint8_t *dat, { struct nand_chip *nand = (struct nand_chip *)(mtd->priv); struct gpmc_nand_info *oinfo = (struct gpmc_nand_info *)(nand->priv); - int i, j, eccflag, count, totalcount, actual_eccsize; + int i, j, eccflag, totalcount, actual_eccsize; + const uint8_t *erased_ecc_vec; unsigned int err_loc[8]; + int bitflip_count; + int bch_max_err; int eccsteps = oinfo->nand.ecc.steps; int eccsize = oinfo->nand.ecc.bytes; @@ -304,9 +310,13 @@ static int omap_correct_bch(struct mtd_info *mtd, uint8_t *dat, case OMAP_ECC_BCH8_CODE_HW: eccsize /= eccsteps; actual_eccsize = eccsize; + erased_ecc_vec = bch8_vector; + bch_max_err = BCH8_MAX_ERROR; break; case OMAP_ECC_BCH8_CODE_HW_ROMCODE: actual_eccsize = eccsize - 1; + erased_ecc_vec = bch8_vector; + bch_max_err = BCH8_MAX_ERROR; break; default: dev_err(oinfo->pdev, "invalid driver configuration\n"); @@ -316,37 +326,49 @@ static int omap_correct_bch(struct mtd_info *mtd, uint8_t *dat, totalcount = 0; for (i = 0; i < eccsteps; i++) { - /* check if any ecc error */ + bool is_error_reported = false; + bitflip_count = 0; eccflag = 0; + + /* check for any ecc error */ for (j = 0; (j < actual_eccsize) && (eccflag == 0); j++) { - if (calc_ecc[j] != 0) + if (calc_ecc[j] != 0) { eccflag = 1; + break; + } } if (eccflag == 1) { - eccflag = 0; - for (j = 0; (j < actual_eccsize) && - (eccflag == 0); j++) - if (read_ecc[j] != 0xFF) - eccflag = 1; + if (memcmp(calc_ecc, erased_ecc_vec, actual_eccsize) == 0) { + /* + * calc_ecc[] matches pattern for ECC + * (all 0xff) so this is definitely + * an erased-page + */ + } else { + bitflip_count = nand_check_erased_ecc_chunk( + dat, oinfo->nand.ecc.size, read_ecc, + eccsize, NULL, 0, bch_max_err); + if (bitflip_count < 0) + is_error_reported = true; + } } - count = 0; - if (eccflag == 1) { - count = omap_gpmc_decode_bch(1, calc_ecc, err_loc); - if (count < 0) - return count; - else - totalcount += count; - } + if (is_error_reported) { + bitflip_count = omap_gpmc_decode_bch(1, + calc_ecc, err_loc); + if (bitflip_count < 0) + return bitflip_count; - for (j = 0; j < count; j++) { - if (err_loc[j] < 4096) - dat[err_loc[j] >> 3] ^= + for (j = 0; j < bitflip_count; j++) { + if (err_loc[j] < 4096) + dat[err_loc[j] >> 3] ^= 1 << (err_loc[j] & 7); - /* else, not interested to correct ecc */ + /* else, not interested to correct ecc */ + } } + totalcount += bitflip_count; calc_ecc = calc_ecc + actual_eccsize; read_ecc = read_ecc + eccsize; dat += 512; -- cgit v1.2.3