This patch is a patch to support TOSHIBA MEMORY CORPORATION BENAND memory devices. This use vendor specific command (TOSHIBA_NAND_CMD_ECC_STATUS) to know the exact bitflips. However, I could not test this patch because I do not have a platform that supports chip-> exec_op. Therefore, I post this patch as RFC.
As soon as I get a platform that supports chip-> exec_op, I would like to test and re-post. Signed-off-by: KOBAYASHI Yoshitake <yoshitake.kobaya...@toshiba.co.jp> --- drivers/mtd/nand/raw/nand_toshiba.c | 53 ++++++++++++++++++++++++++++++++++++- 1 file changed, 52 insertions(+), 1 deletion(-) diff --git a/drivers/mtd/nand/raw/nand_toshiba.c b/drivers/mtd/nand/raw/nand_toshiba.c index 8aec3fa..3f4683b 100644 --- a/drivers/mtd/nand/raw/nand_toshiba.c +++ b/drivers/mtd/nand/raw/nand_toshiba.c @@ -23,14 +23,65 @@ /* Recommended to rewrite for BENAND */ #define TOSHIBA_NAND_STATUS_REWRITE_RECOMMENDED BIT(3) +/* ECC Status Read Command for BENAND */ +#define TOSHIBA_NAND_CMD_ECC_STATUS_READ 0x7A + +/* ECC Status Mask for BENAND */ +#define TOSHIBA_NAND_ECC_STATUS_MASK 0x0F + +/* Uncorrectable Error for BENAND */ +#define TOSHIBA_NAND_ECC_STATUS_UNCORR 0x0F + +static int toshiba_nand_benand_read_eccstatus_op(struct nand_chip *chip, + u8 *buf) +{ + u8 *ecc_status = buf; + + if (chip->exec_op) { + const struct nand_sdr_timings *sdr = + nand_get_sdr_timings(&chip->data_interface); + struct nand_op_instr instrs[] = { + NAND_OP_CMD(TOSHIBA_NAND_CMD_ECC_STATUS_READ, + PSEC_TO_NSEC(sdr->tADL_min)), + NAND_OP_8BIT_DATA_IN(chip->ecc.steps, ecc_status, 0), + }; + struct nand_operation op = NAND_OPERATION(instrs); + + return nand_exec_op(chip, &op); + } + + return -ENOTSUPP; +} + static int toshiba_nand_benand_eccstatus(struct mtd_info *mtd, struct nand_chip *chip) { int ret; unsigned int max_bitflips = 0; - u8 status; + u8 status, ecc_status[8]; /* Check Status */ + ret = toshiba_nand_benand_read_eccstatus_op(chip, ecc_status); + if (!ret) { + unsigned int i, bitflips = 0; + + for (i = 0; i < chip->ecc.steps; i++) { + bitflips = ecc_status[i] & TOSHIBA_NAND_ECC_STATUS_MASK; + if (bitflips == TOSHIBA_NAND_ECC_STATUS_UNCORR) { + mtd->ecc_stats.failed++; + } else { + mtd->ecc_stats.corrected += bitflips; + max_bitflips = max(max_bitflips, bitflips); + } + } + + return max_bitflips; + } + + /* + * Fallback to regular status check if + * toshiba_nand_benand_read_eccstatus_op() failed. + */ ret = nand_status_op(chip, &status); if (ret) return ret; -- 2.7.4