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mtd: rawnand: micron: support 8/512 on-die ECC

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Micron MT29F1G08ABAFAWP-ITE:F supports an on-die ECC with 8 bits
per 512 bytes. Add support for this combination.

Signed-off-by: Chris Packham <chris.packham@alliedtelesis.co.nz>
Reviewed-by: Boris Brezillon <boris.brezillon@bootlin.com>
Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
This commit is contained in:
Chris Packham 2018-07-18 10:42:16 +02:00 committed by Miquel Raynal
parent dbc44edbf8
commit 3ec7cb369e
1 changed files with 131 additions and 30 deletions
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161
drivers/mtd/nand/raw/nand_micron.c
View File

@ -18,10 +18,30 @@
#include <linux/mtd/rawnand.h>
/*
* Special Micron status bit that indicates when the block has been
* corrected by on-die ECC and should be rewritten
* Special Micron status bit 3 indicates that the block has been
* corrected by on-die ECC and should be rewritten.
*/
#define NAND_STATUS_WRITE_RECOMMENDED BIT(3)
#define NAND_ECC_STATUS_WRITE_RECOMMENDED BIT(3)
/*
* On chips with 8-bit ECC and additional bit can be used to distinguish
* cases where a errors were corrected without needing a rewrite
*
* Bit 4 Bit 3 Bit 0 Description
* ----- ----- ----- -----------
* 0 0 0 No Errors
* 0 0 1 Multiple uncorrected errors
* 0 1 0 4 - 6 errors corrected, recommend rewrite
* 0 1 1 Reserved
* 1 0 0 1 - 3 errors corrected
* 1 0 1 Reserved
* 1 1 0 7 - 8 errors corrected, recommend rewrite
*/
#define NAND_ECC_STATUS_MASK (BIT(4) | BIT(3) | BIT(0))
#define NAND_ECC_STATUS_UNCORRECTABLE BIT(0)
#define NAND_ECC_STATUS_4_6_CORRECTED BIT(3)
#define NAND_ECC_STATUS_1_3_CORRECTED BIT(4)
#define NAND_ECC_STATUS_7_8_CORRECTED (BIT(4) | BIT(3))
struct nand_onfi_vendor_micron {
u8 two_plane_read;
@ -74,8 +94,9 @@ static int micron_nand_onfi_init(struct nand_chip *chip)
return 0;
}
static int micron_nand_on_die_ooblayout_ecc(struct mtd_info *mtd, int section,
struct mtd_oob_region *oobregion)
static int micron_nand_on_die_4_ooblayout_ecc(struct mtd_info *mtd,
int section,
struct mtd_oob_region *oobregion)
{
if (section >= 4)
return -ERANGE;
@ -86,8 +107,9 @@ static int micron_nand_on_die_ooblayout_ecc(struct mtd_info *mtd, int section,
return 0;
}
static int micron_nand_on_die_ooblayout_free(struct mtd_info *mtd, int section,
struct mtd_oob_region *oobregion)
static int micron_nand_on_die_4_ooblayout_free(struct mtd_info *mtd,
int section,
struct mtd_oob_region *oobregion)
{
if (section >= 4)
return -ERANGE;
@ -98,9 +120,44 @@ static int micron_nand_on_die_ooblayout_free(struct mtd_info *mtd, int section,
return 0;
}
static const struct mtd_ooblayout_ops micron_nand_on_die_ooblayout_ops = {
.ecc = micron_nand_on_die_ooblayout_ecc,
.free = micron_nand_on_die_ooblayout_free,
static const struct mtd_ooblayout_ops micron_nand_on_die_4_ooblayout_ops = {
.ecc = micron_nand_on_die_4_ooblayout_ecc,
.free = micron_nand_on_die_4_ooblayout_free,
};
static int micron_nand_on_die_8_ooblayout_ecc(struct mtd_info *mtd,
int section,
struct mtd_oob_region *oobregion)
{
struct nand_chip *chip = mtd_to_nand(mtd);
if (section)
return -ERANGE;
oobregion->offset = mtd->oobsize - chip->ecc.total;
oobregion->length = chip->ecc.total;
return 0;
}
static int micron_nand_on_die_8_ooblayout_free(struct mtd_info *mtd,
int section,
struct mtd_oob_region *oobregion)
{
struct nand_chip *chip = mtd_to_nand(mtd);
if (section)
return -ERANGE;
oobregion->offset = 2;
oobregion->length = mtd->oobsize - chip->ecc.total - 2;
return 0;
}
static const struct mtd_ooblayout_ops micron_nand_on_die_8_ooblayout_ops = {
.ecc = micron_nand_on_die_8_ooblayout_ecc,
.free = micron_nand_on_die_8_ooblayout_free,
};
static int micron_nand_on_die_ecc_setup(struct nand_chip *chip, bool enable)
@ -113,6 +170,55 @@ static int micron_nand_on_die_ecc_setup(struct nand_chip *chip, bool enable)
return nand_set_features(chip, ONFI_FEATURE_ON_DIE_ECC, feature);
}
static int micron_nand_on_die_ecc_status_4(struct nand_chip *chip, u8 status)
{
struct mtd_info *mtd = nand_to_mtd(chip);
/*
* The internal ECC doesn't tell us the number of bitflips
* that have been corrected, but tells us if it recommends to
* rewrite the block. If it's the case, then we pretend we had
* a number of bitflips equal to the ECC strength, which will
* hint the NAND core to rewrite the block.
*/
if (status & NAND_STATUS_FAIL) {
mtd->ecc_stats.failed++;
} else if (status & NAND_ECC_STATUS_WRITE_RECOMMENDED) {
mtd->ecc_stats.corrected += chip->ecc.strength;
return chip->ecc.strength;
}
return 0;
}
static int micron_nand_on_die_ecc_status_8(struct nand_chip *chip, u8 status)
{
struct mtd_info *mtd = nand_to_mtd(chip);
/*
* With 8/512 we have more information but still don't know precisely
* how many bit-flips were seen.
*/
switch (status & NAND_ECC_STATUS_MASK) {
case NAND_ECC_STATUS_UNCORRECTABLE:
mtd->ecc_stats.failed++;
return 0;
case NAND_ECC_STATUS_1_3_CORRECTED:
mtd->ecc_stats.corrected += 3;
return 3;
case NAND_ECC_STATUS_4_6_CORRECTED:
mtd->ecc_stats.corrected += 6;
/* rewrite recommended */
return 6;
case NAND_ECC_STATUS_7_8_CORRECTED:
mtd->ecc_stats.corrected += 8;
/* rewrite recommended */
return 8;
default:
return 0;
}
}
static int
micron_nand_read_page_on_die_ecc(struct mtd_info *mtd, struct nand_chip *chip,
uint8_t *buf, int oob_required,
@ -137,19 +243,10 @@ micron_nand_read_page_on_die_ecc(struct mtd_info *mtd, struct nand_chip *chip,
if (ret)
goto out;
if (status & NAND_STATUS_FAIL) {
mtd->ecc_stats.failed++;
} else if (status & NAND_STATUS_WRITE_RECOMMENDED) {
/*
* The internal ECC doesn't tell us the number of bitflips
* that have been corrected, but tells us if it recommends to
* rewrite the block. If it's the case, then we pretend we had
* a number of bitflips equal to the ECC strength, which will
* hint the NAND core to rewrite the block.
*/
mtd->ecc_stats.corrected += chip->ecc.strength;
max_bitflips = chip->ecc.strength;
}
if (chip->ecc.strength == 4)
max_bitflips = micron_nand_on_die_ecc_status_4(chip, status);
else
max_bitflips = micron_nand_on_die_ecc_status_8(chip, status);
ret = nand_read_data_op(chip, buf, mtd->writesize, false);
if (!ret && oob_required)
@ -254,10 +351,9 @@ static int micron_supports_on_die_ecc(struct nand_chip *chip)
return MICRON_ON_DIE_MANDATORY;
/*
* Some Micron NANDs have an on-die ECC of 4/512, some other
* 8/512. We only support the former.
* We only support on-die ECC of 4/512 or 8/512
*/
if (chip->ecc_strength_ds != 4)
if (chip->ecc_strength_ds != 4 && chip->ecc_strength_ds != 8)
return MICRON_ON_DIE_UNSUPPORTED;
return MICRON_ON_DIE_SUPPORTED;
@ -289,16 +385,21 @@ static int micron_nand_init(struct nand_chip *chip)
return -EINVAL;
}
chip->ecc.bytes = 8;
if (chip->ecc_strength_ds == 4)
mtd_set_ooblayout(mtd,
&micron_nand_on_die_4_ooblayout_ops);
else
mtd_set_ooblayout(mtd,
&micron_nand_on_die_8_ooblayout_ops);
chip->ecc.bytes = chip->ecc_strength_ds * 2;
chip->ecc.size = 512;
chip->ecc.strength = 4;
chip->ecc.strength = chip->ecc_strength_ds;
chip->ecc.algo = NAND_ECC_BCH;
chip->ecc.read_page = micron_nand_read_page_on_die_ecc;
chip->ecc.write_page = micron_nand_write_page_on_die_ecc;
chip->ecc.read_page_raw = nand_read_page_raw;
chip->ecc.write_page_raw = nand_write_page_raw;
mtd_set_ooblayout(mtd, &micron_nand_on_die_ooblayout_ops);
}
return 0;