diff options
| -rw-r--r-- | drivers/mtd/nand/nand_hynix.c | 357 |
1 files changed, 356 insertions, 1 deletions
diff --git a/drivers/mtd/nand/nand_hynix.c b/drivers/mtd/nand/nand_hynix.c index 57c4ed894dfb..2a5d0efea498 100644 --- a/drivers/mtd/nand/nand_hynix.c +++ b/drivers/mtd/nand/nand_hynix.c @@ -17,6 +17,53 @@ #include <linux/mtd/nand.h> #include <linux/sizes.h> +#include <linux/slab.h> + +#define NAND_HYNIX_CMD_SET_PARAMS 0x36 +#define NAND_HYNIX_CMD_APPLY_PARAMS 0x16 + +#define NAND_HYNIX_1XNM_RR_REPEAT 8 + +/** + * struct hynix_read_retry - read-retry data + * @nregs: number of register to set when applying a new read-retry mode + * @regs: register offsets (NAND chip dependent) + * @values: array of values to set in registers. The array size is equal to + * (nregs * nmodes) + */ +struct hynix_read_retry { + int nregs; + const u8 *regs; + u8 values[0]; +}; + +/** + * struct hynix_nand - private Hynix NAND struct + * @nand_technology: manufacturing process expressed in picometer + * @read_retry: read-retry information + */ +struct hynix_nand { + const struct hynix_read_retry *read_retry; +}; + +/** + * struct hynix_read_retry_otp - structure describing how the read-retry OTP + * area + * @nregs: number of hynix private registers to set before reading the reading + * the OTP area + * @regs: registers that should be configured + * @values: values that should be set in regs + * @page: the address to pass to the READ_PAGE command. Depends on the NAND + * chip + * @size: size of the read-retry OTP section + */ +struct hynix_read_retry_otp { + int nregs; + const u8 *regs; + const u8 *values; + int page; + int size; +}; static bool hynix_nand_has_valid_jedecid(struct nand_chip *chip) { @@ -31,6 +78,288 @@ static bool hynix_nand_has_valid_jedecid(struct nand_chip *chip) return !strcmp("JEDEC", jedecid); } +static int hynix_nand_setup_read_retry(struct mtd_info *mtd, int retry_mode) +{ + struct nand_chip *chip = mtd_to_nand(mtd); + struct hynix_nand *hynix = nand_get_manufacturer_data(chip); + const u8 *values; + int status; + int i; + + values = hynix->read_retry->values + + (retry_mode * hynix->read_retry->nregs); + + /* Enter 'Set Hynix Parameters' mode */ + chip->cmdfunc(mtd, NAND_HYNIX_CMD_SET_PARAMS, -1, -1); + + /* + * Configure the NAND in the requested read-retry mode. + * This is done by setting pre-defined values in internal NAND + * registers. + * + * The set of registers is NAND specific, and the values are either + * predefined or extracted from an OTP area on the NAND (values are + * probably tweaked at production in this case). + */ + for (i = 0; i < hynix->read_retry->nregs; i++) { + int column = hynix->read_retry->regs[i]; + + column |= column << 8; + chip->cmdfunc(mtd, NAND_CMD_NONE, column, -1); + chip->write_byte(mtd, values[i]); + } + + /* Apply the new settings. */ + chip->cmdfunc(mtd, NAND_HYNIX_CMD_APPLY_PARAMS, -1, -1); + + status = chip->waitfunc(mtd, chip); + if (status & NAND_STATUS_FAIL) + return -EIO; + + return 0; +} + +/** + * hynix_get_majority - get the value that is occurring the most in a given + * set of values + * @in: the array of values to test + * @repeat: the size of the in array + * @out: pointer used to store the output value + * + * This function implements the 'majority check' logic that is supposed to + * overcome the unreliability of MLC NANDs when reading the OTP area storing + * the read-retry parameters. + * + * It's based on a pretty simple assumption: if we repeat the same value + * several times and then take the one that is occurring the most, we should + * find the correct value. + * Let's hope this dummy algorithm prevents us from losing the read-retry + * parameters. + */ +static int hynix_get_majority(const u8 *in, int repeat, u8 *out) +{ + int i, j, half = repeat / 2; + + /* + * We only test the first half of the in array because we must ensure + * that the value is at least occurring repeat / 2 times. + * + * This loop is suboptimal since we may count the occurrences of the + * same value several time, but we are doing that on small sets, which + * makes it acceptable. + */ + for (i = 0; i < half; i++) { + int cnt = 0; + u8 val = in[i]; + + /* Count all values that are matching the one at index i. */ + for (j = i + 1; j < repeat; j++) { + if (in[j] == val) + cnt++; + } + + /* We found a value occurring more than repeat / 2. */ + if (cnt > half) { + *out = val; + return 0; + } + } + + return -EIO; +} + +static int hynix_read_rr_otp(struct nand_chip *chip, + const struct hynix_read_retry_otp *info, + void *buf) +{ + struct mtd_info *mtd = nand_to_mtd(chip); + int i; + + chip->cmdfunc(mtd, NAND_CMD_RESET, -1, -1); + + chip->cmdfunc(mtd, NAND_HYNIX_CMD_SET_PARAMS, -1, -1); + + for (i = 0; i < info->nregs; i++) { + int column = info->regs[i]; + + column |= column << 8; + chip->cmdfunc(mtd, NAND_CMD_NONE, column, -1); + chip->write_byte(mtd, info->values[i]); + } + + chip->cmdfunc(mtd, NAND_HYNIX_CMD_APPLY_PARAMS, -1, -1); + + /* Sequence to enter OTP mode? */ + chip->cmdfunc(mtd, 0x17, -1, -1); + chip->cmdfunc(mtd, 0x04, -1, -1); + chip->cmdfunc(mtd, 0x19, -1, -1); + + /* Now read the page */ + chip->cmdfunc(mtd, NAND_CMD_READ0, 0x0, info->page); + chip->read_buf(mtd, buf, info->size); + + /* Put everything back to normal */ + chip->cmdfunc(mtd, NAND_CMD_RESET, -1, -1); + chip->cmdfunc(mtd, NAND_HYNIX_CMD_SET_PARAMS, 0x38, -1); + chip->write_byte(mtd, 0x0); + chip->cmdfunc(mtd, NAND_HYNIX_CMD_APPLY_PARAMS, -1, -1); + chip->cmdfunc(mtd, NAND_CMD_READ0, 0x0, -1); + + return 0; +} + +#define NAND_HYNIX_1XNM_RR_COUNT_OFFS 0 +#define NAND_HYNIX_1XNM_RR_REG_COUNT_OFFS 8 +#define NAND_HYNIX_1XNM_RR_SET_OFFS(x, setsize, inv) \ + (16 + ((((x) * 2) + ((inv) ? 1 : 0)) * (setsize))) + +static int hynix_mlc_1xnm_rr_value(const u8 *buf, int nmodes, int nregs, + int mode, int reg, bool inv, u8 *val) +{ + u8 tmp[NAND_HYNIX_1XNM_RR_REPEAT]; + int val_offs = (mode * nregs) + reg; + int set_size = nmodes * nregs; + int i, ret; + + for (i = 0; i < NAND_HYNIX_1XNM_RR_REPEAT; i++) { + int set_offs = NAND_HYNIX_1XNM_RR_SET_OFFS(i, set_size, inv); + + tmp[i] = buf[val_offs + set_offs]; + } + + ret = hynix_get_majority(tmp, NAND_HYNIX_1XNM_RR_REPEAT, val); + if (ret) + return ret; + + if (inv) + *val = ~*val; + + return 0; +} + +static u8 hynix_1xnm_mlc_read_retry_regs[] = { + 0xcc, 0xbf, 0xaa, 0xab, 0xcd, 0xad, 0xae, 0xaf +}; + +static int hynix_mlc_1xnm_rr_init(struct nand_chip *chip, + const struct hynix_read_retry_otp *info) +{ + struct hynix_nand *hynix = nand_get_manufacturer_data(chip); + struct hynix_read_retry *rr = NULL; + int ret, i, j; + u8 nregs, nmodes; + u8 *buf; + + buf = kmalloc(info->size, GFP_KERNEL); + if (!buf) + return -ENOMEM; + + ret = hynix_read_rr_otp(chip, info, buf); + if (ret) + goto out; + + ret = hynix_get_majority(buf, NAND_HYNIX_1XNM_RR_REPEAT, + &nmodes); + if (ret) + goto out; + + ret = hynix_get_majority(buf + NAND_HYNIX_1XNM_RR_REPEAT, + NAND_HYNIX_1XNM_RR_REPEAT, + &nregs); + if (ret) + goto out; + + rr = kzalloc(sizeof(*rr) + (nregs * nmodes), GFP_KERNEL); + if (!rr) + goto out; + + for (i = 0; i < nmodes; i++) { + for (j = 0; j < nregs; j++) { + u8 *val = rr->values + (i * nregs); + + ret = hynix_mlc_1xnm_rr_value(buf, nmodes, nregs, i, j, + false, val); + if (!ret) + continue; + + ret = hynix_mlc_1xnm_rr_value(buf, nmodes, nregs, i, j, + true, val); + if (ret) + goto out; + } + } + + rr->nregs = nregs; + rr->regs = hynix_1xnm_mlc_read_retry_regs; + hynix->read_retry = rr; + chip->setup_read_retry = hynix_nand_setup_read_retry; + chip->read_retries = nmodes; + +out: + kfree(buf); + + if (ret) + kfree(rr); + + return ret; +} + +static const u8 hynix_mlc_1xnm_rr_otp_regs[] = { 0x38 }; +static const u8 hynix_mlc_1xnm_rr_otp_values[] = { 0x52 }; + +static const struct hynix_read_retry_otp hynix_mlc_1xnm_rr_otps[] = { + { + .nregs = ARRAY_SIZE(hynix_mlc_1xnm_rr_otp_regs), + .regs = hynix_mlc_1xnm_rr_otp_regs, + .values = hynix_mlc_1xnm_rr_otp_values, + .page = 0x21f, + .size = 784 + }, + { + .nregs = ARRAY_SIZE(hynix_mlc_1xnm_rr_otp_regs), + .regs = hynix_mlc_1xnm_rr_otp_regs, + .values = hynix_mlc_1xnm_rr_otp_values, + .page = 0x200, + .size = 528, + }, +}; + +static int hynix_nand_rr_init(struct nand_chip *chip) +{ + int i, ret = 0; + bool valid_jedecid; + + valid_jedecid = hynix_nand_has_valid_jedecid(chip); + + /* + * We only support read-retry for 1xnm NANDs, and those NANDs all + * expose a valid JEDEC ID. + */ + if (valid_jedecid) { + u8 nand_tech = chip->id.data[5] >> 4; + + /* 1xnm technology */ + if (nand_tech == 4) { + for (i = 0; i < ARRAY_SIZE(hynix_mlc_1xnm_rr_otps); + i++) { + /* + * FIXME: Hynix recommend to copy the + * read-retry OTP area into a normal page. + */ + ret = hynix_mlc_1xnm_rr_init(chip, + hynix_mlc_1xnm_rr_otps); + if (!ret) + break; + } + } + } + + if (ret) + pr_warn("failed to initialize read-retry infrastructure"); + + return 0; +} + static void hynix_nand_extract_oobsize(struct nand_chip *chip, bool valid_jedecid) { @@ -258,17 +587,43 @@ static void hynix_nand_decode_id(struct nand_chip *chip) hynix_nand_extract_scrambling_requirements(chip, valid_jedecid); } +static void hynix_nand_cleanup(struct nand_chip *chip) +{ + struct hynix_nand *hynix = nand_get_manufacturer_data(chip); + + if (!hynix) + return; + + kfree(hynix->read_retry); + kfree(hynix); + nand_set_manufacturer_data(chip, NULL); +} + static int hynix_nand_init(struct nand_chip *chip) { + struct hynix_nand *hynix; + int ret; + if (!nand_is_slc(chip)) chip->bbt_options |= NAND_BBT_SCANLASTPAGE; else chip->bbt_options |= NAND_BBT_SCAN2NDPAGE; - return 0; + hynix = kzalloc(sizeof(*hynix), GFP_KERNEL); + if (!hynix) + return -ENOMEM; + + nand_set_manufacturer_data(chip, hynix); + + ret = hynix_nand_rr_init(chip); + if (ret) + hynix_nand_cleanup(chip); + + return ret; } const struct nand_manufacturer_ops hynix_nand_manuf_ops = { .detect = hynix_nand_decode_id, .init = hynix_nand_init, + .cleanup = hynix_nand_cleanup, }; |