i.MX6QP and i.MX7D BCH module integrated a new feature to detect the bitflip number for erased NAND page. So for these two platform, set the erase threshold to ecc_strength and if bitflip detected, GPMI driver will correct the data to all 0xFF.
Signed-off-by: Han Xu <[email protected]> --- drivers/mtd/nand/gpmi-nand/bch-regs.h | 10 ++++++++++ drivers/mtd/nand/gpmi-nand/gpmi-lib.c | 5 +++++ drivers/mtd/nand/gpmi-nand/gpmi-nand.c | 27 ++++++++++++++++++++++++++- 3 files changed, 41 insertions(+), 1 deletion(-) diff --git a/drivers/mtd/nand/gpmi-nand/bch-regs.h b/drivers/mtd/nand/gpmi-nand/bch-regs.h index 228142c..2c44b88 100644 --- a/drivers/mtd/nand/gpmi-nand/bch-regs.h +++ b/drivers/mtd/nand/gpmi-nand/bch-regs.h @@ -30,7 +30,13 @@ #define BM_BCH_CTRL_COMPLETE_IRQ (1 << 0) #define HW_BCH_STATUS0 0x00000010 + #define HW_BCH_MODE 0x00000020 +#define BP_BCH_MODE_ERASE_THRESHOLD 0 +#define BM_BCH_MODE_ERASE_THRESHOLD (0xff << BP_BCH_MODE_ERASE_THRESHOLD) +#define BF_BCH_MODE_ERASE_THRESHOLD(v) \ + (((v) << BP_BCH_MODE_ERASE_THRESHOLD) & BM_BCH_MODE_ERASE_THRESHOLD) + #define HW_BCH_ENCODEPTR 0x00000030 #define HW_BCH_DATAPTR 0x00000040 #define HW_BCH_METAPTR 0x00000050 @@ -125,4 +131,8 @@ ) #define HW_BCH_VERSION 0x00000160 +#define HW_BCH_DEBUG1 0x00000170 +#define BP_BCH_DEBUG1_ERASED_ZERO_COUNT 0 +#define BM_BCH_DEBUG1_ERASED_ZERO_COUNT \ + (0x1ff << BP_BCH_DEBUG1_ERASED_ZERO_COUNT) #endif diff --git a/drivers/mtd/nand/gpmi-nand/gpmi-lib.c b/drivers/mtd/nand/gpmi-nand/gpmi-lib.c index 358ff5d..0b5666a 100644 --- a/drivers/mtd/nand/gpmi-nand/gpmi-lib.c +++ b/drivers/mtd/nand/gpmi-nand/gpmi-lib.c @@ -298,6 +298,11 @@ int bch_set_geometry(struct gpmi_nand_data *this) | BF_BCH_FLASH0LAYOUT1_DATAN_SIZE(block_size, this), r->bch_regs + HW_BCH_FLASH0LAYOUT1); + /* Set erase threshold to ecc_strength for mx6qp and mx7 */ + if (GPMI_IS_MX6QP(this) || GPMI_IS_MX7(this)) + writel(BF_BCH_MODE_ERASE_THRESHOLD(ecc_strength), + r->bch_regs + HW_BCH_MODE); + /* Set *all* chip selects to use layout 0. */ writel(0, r->bch_regs + HW_BCH_LAYOUTSELECT); diff --git a/drivers/mtd/nand/gpmi-nand/gpmi-nand.c b/drivers/mtd/nand/gpmi-nand/gpmi-nand.c index aedaff3..03bdb4d 100644 --- a/drivers/mtd/nand/gpmi-nand/gpmi-nand.c +++ b/drivers/mtd/nand/gpmi-nand/gpmi-nand.c @@ -1043,6 +1043,7 @@ static int gpmi_ecc_read_page(struct mtd_info *mtd, struct nand_chip *chip, { struct gpmi_nand_data *this = nand_get_controller_data(chip); struct bch_geometry *nfc_geo = &this->bch_geometry; + void __iomem *bch_regs = this->resources.bch_regs; void *payload_virt; dma_addr_t payload_phys; void *auxiliary_virt; @@ -1051,6 +1052,8 @@ static int gpmi_ecc_read_page(struct mtd_info *mtd, struct nand_chip *chip, unsigned char *status; unsigned int max_bitflips = 0; int ret; + int bitflips = 0; + int bitflip_flag = 0; dev_dbg(this->dev, "page number is : %d\n", page); ret = read_page_prepare(this, buf, nfc_geo->payload_size, @@ -1088,8 +1091,20 @@ static int gpmi_ecc_read_page(struct mtd_info *mtd, struct nand_chip *chip, payload_virt, payload_phys); for (i = 0; i < nfc_geo->ecc_chunk_count; i++, status++) { - if ((*status == STATUS_GOOD) || (*status == STATUS_ERASED)) + if (*status == STATUS_GOOD) + continue; + if (*status == STATUS_ERASED) { + if (GPMI_IS_MX6QP(this) || GPMI_IS_MX7(this)) { + bitflips = readl(bch_regs + HW_BCH_DEBUG1); + if (bitflips) { + bitflip_flag = 1; + max_bitflips = max_t(unsigned int, + max_bitflips, + bitflips); + } + } continue; + } if (*status == STATUS_UNCORRECTABLE) { int eccbits = nfc_geo->ecc_strength * nfc_geo->gf_len; @@ -1098,6 +1113,10 @@ static int gpmi_ecc_read_page(struct mtd_info *mtd, struct nand_chip *chip, int eccbytes; int flips; + /* shortcut for i.MX7 and i.MX6QP */ + if (GPMI_IS_MX6QP(this) || GPMI_IS_MX7(this)) + continue; + /* Read ECC bytes into our internal raw_buffer */ offset = nfc_geo->metadata_size * 8; offset += ((8 * nfc_geo->ecc_chunk_size) + eccbits) * (i + 1); @@ -1182,6 +1201,12 @@ static int gpmi_ecc_read_page(struct mtd_info *mtd, struct nand_chip *chip, chip->oob_poi[0] = ((uint8_t *) auxiliary_virt)[0]; } + /* if bitflip occurred in erased page, change data to all 0xff */ + if (bitflip_flag) { + memset(buf, ~0, nfc_geo->payload_size); + memset(chip->oob_poi, ~0, mtd->oobsize); + } + return max_bitflips; } -- 1.9.1
