On Wed, 6 Dec 2017 23:04:58 +0900 KOBAYASHI Yoshitake <[email protected]> wrote:
> This patch enables support for Toshiba Memory BENAND. This checks > internal ECC status in read operation when using BENAND and selecting > ECC mode as on-die. > > Signed-off-by: KOBAYASHI Yoshitake <[email protected]> > --- > drivers/mtd/nand/nand_toshiba.c | 89 > +++++++++++++++++++++++++++++++++++++++++ > 1 file changed, 89 insertions(+) > > diff --git a/drivers/mtd/nand/nand_toshiba.c b/drivers/mtd/nand/nand_toshiba.c > index c2c141b..35c0ddf 100644 > --- a/drivers/mtd/nand/nand_toshiba.c > +++ b/drivers/mtd/nand/nand_toshiba.c > @@ -17,6 +17,91 @@ > > #include <linux/mtd/rawnand.h> > > +/* ECC Status Read Command for BENAND */ > +#define TOSHIBA_NAND_CMD_ECC_STATUS 0x7A > + > +/* Recommended to rewrite for BENAND */ > +#define TOSHIBA_NAND_STATUS_REWRITE_RECOMMENDED BIT(3) > + > +static int toshiba_nand_benand_status_chk(struct mtd_info *mtd, > + struct nand_chip *chip) > +{ > + unsigned int max_bitflips = 0; > + u8 status; > + > + /* Check Read Status */ > + chip->cmdfunc(mtd, NAND_CMD_STATUS, -1, -1); > + status = chip->read_byte(mtd); Please use the recently introduced nand_status_op() helper. > + > + /* > + * TOSHIBA_NAND_CMD_ECC_STATUS is vendor specific command. > + * Currently we have no way to send arbitrary sequences of > + * CMD+ADDR+DATA cycles and thus cannot support this custom > + * TOSHIBA_NAND_CMD_ECC_STATUS operation. That's about to change :-), if everything goes well, nand_exec_op() should be available in 4.16. > + * For now, we set max_bitflips mtd->bitflip_threshold. > + */ > + if (status & NAND_STATUS_FAIL) { > + /* uncorrectable */ > + mtd->ecc_stats.failed++; > + } else if (status & TOSHIBA_NAND_STATUS_REWRITE_RECOMMENDED) { > + /* correctable */ > + max_bitflips = mtd->bitflip_threshold; > + mtd->ecc_stats.corrected += max_bitflips; > + } > + > + return max_bitflips; > +} > + > +static int > +toshiba_nand_read_page_benand(struct mtd_info *mtd, > + struct nand_chip *chip, uint8_t *buf, > + int oob_required, int page) > +{ > + nand_read_page_raw(mtd, chip, buf, oob_required, page); Please check the return code of nand_read_page_raw(). > + > + return toshiba_nand_benand_status_chk(mtd, chip); > +} > + > +static int > +toshiba_nand_read_subpage_benand(struct mtd_info *mtd, > + struct nand_chip *chip, uint32_t data_offs, > + uint32_t readlen, uint8_t *bufpoi, int page) > +{ > + uint8_t *p; > + > + if (data_offs != 0) > + chip->cmdfunc(mtd, NAND_CMD_RNDOUT, data_offs, -1); > + > + p = bufpoi + data_offs; > + chip->read_buf(mtd, p, readlen); The core is no longer sending the initial READ0 command, so this should be turned into: ret = nand_read_page_op(chip, data_offs, bufpoi + data_offs, readlen); if (ret) return ret; > + > + return toshiba_nand_benand_status_chk(mtd, chip); > +} > + > +static void toshiba_nand_benand_init(struct nand_chip *chip) > +{ > + struct mtd_info *mtd = nand_to_mtd(chip); > + > + /* > + * On BENAND, the entire OOB region can be used by the MTD user. > + * The calculated ECC bytes are stored into other isolated > + * area which is not accessible to users. > + * This is why chip->ecc.bytes = 0. > + */ > + chip->ecc.bytes = 0; > + chip->ecc.size = 512; > + chip->ecc.strength = 8; > + chip->ecc.read_page = toshiba_nand_read_page_benand; > + chip->ecc.read_subpage = toshiba_nand_read_subpage_benand; > + chip->ecc.write_page = nand_write_page_raw; > + chip->ecc.read_page_raw = nand_read_page_raw; > + chip->ecc.write_page_raw = nand_write_page_raw; > + > + chip->options |= NAND_SUBPAGE_READ; > + > + mtd_set_ooblayout(mtd, &nand_ooblayout_lp_ops); > +} > + > static void toshiba_nand_decode_id(struct nand_chip *chip) > { > struct mtd_info *mtd = nand_to_mtd(chip); > @@ -70,6 +155,10 @@ static int toshiba_nand_init(struct nand_chip *chip) > if (nand_is_slc(chip)) > chip->bbt_options |= NAND_BBT_SCAN2NDPAGE; > > + if (nand_is_slc(chip) && (chip->id.data[4] & 0x80) /* BENAND */ && > + (chip->ecc.mode == NAND_ECC_ON_DIE)) > + toshiba_nand_benand_init(chip); > + Please move this block to toshiba_nand_init(). > return 0; > } >
