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authorBoris Brezillon2018-07-18 10:42:15 +0200
committerMiquel Raynal2018-07-19 23:14:14 +0200
commitdbc44edbf8338d27639214be07fe7ab4f8a903e0 (patch)
treeb4417f59196306a55eb0baecdda57894420b7205
parentmtd: rawnand: fsmc: Stop using chip->read_buf() (diff)
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mtd: rawnand: micron: Fix on-die ECC detection logic
Basing the "mandatory on-die" detection on ID byte 2 does not work, because Micron has plenty of NANDs using the same device ID code, and not all of them have forcibly enabled on-die ECC. Since the "Array Operation" feature does not provide the "ECC enabled/disabled" bit when the ECC can't be disabled, let's try to use the "ECC enabled/disabled" bit in the READ_ID bytes. It seems that this bit is dynamically updated on NANDs where on-die ECC can freely be enabled/disabled, so let's hope it stays at one when we have a NAND with on-die ECC forcibly enabled. Fixes: 51f3b3970a8c ("mtd: rawnand: micron: detect forced on-die ECC") Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com> Tested-by: Chris Packham <chris.packham@alliedtelesis.co.nz> Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
-rw-r--r--drivers/mtd/nand/raw/nand_micron.c32
1 files changed, 23 insertions, 9 deletions
diff --git a/drivers/mtd/nand/raw/nand_micron.c b/drivers/mtd/nand/raw/nand_micron.c
index d30bd4df9b12..d85bb4d42686 100644
--- a/drivers/mtd/nand/raw/nand_micron.c
+++ b/drivers/mtd/nand/raw/nand_micron.c
@@ -196,6 +196,9 @@ enum {
MICRON_ON_DIE_MANDATORY,
};
+#define MICRON_ID_INTERNAL_ECC_MASK GENMASK(1, 0)
+#define MICRON_ID_ECC_ENABLED BIT(7)
+
/*
* Try to detect if the NAND support on-die ECC. To do this, we enable
* the feature, and read back if it has been enabled as expected. We
@@ -208,7 +211,7 @@ enum {
*/
static int micron_supports_on_die_ecc(struct nand_chip *chip)
{
- u8 feature[ONFI_SUBFEATURE_PARAM_LEN] = { 0, };
+ u8 id[5];
int ret;
if (!chip->parameters.onfi.version)
@@ -217,26 +220,37 @@ static int micron_supports_on_die_ecc(struct nand_chip *chip)
if (chip->bits_per_cell != 1)
return MICRON_ON_DIE_UNSUPPORTED;
+ /*
+ * We only support on-die ECC of 4/512 or 8/512
+ */
+ if (chip->ecc_strength_ds != 4 && chip->ecc_strength_ds != 8)
+ return MICRON_ON_DIE_UNSUPPORTED;
+
+ /* 0x2 means on-die ECC is available. */
+ if (chip->id.len != 5 ||
+ (chip->id.data[4] & MICRON_ID_INTERNAL_ECC_MASK) != 0x2)
+ return MICRON_ON_DIE_UNSUPPORTED;
+
ret = micron_nand_on_die_ecc_setup(chip, true);
if (ret)
return MICRON_ON_DIE_UNSUPPORTED;
- ret = nand_get_features(chip, ONFI_FEATURE_ON_DIE_ECC, feature);
- if (ret < 0)
- return ret;
+ ret = nand_readid_op(chip, 0, id, sizeof(id));
+ if (ret)
+ return MICRON_ON_DIE_UNSUPPORTED;
- if ((feature[0] & ONFI_FEATURE_ON_DIE_ECC_EN) == 0)
+ if (!(id[4] & MICRON_ID_ECC_ENABLED))
return MICRON_ON_DIE_UNSUPPORTED;
ret = micron_nand_on_die_ecc_setup(chip, false);
if (ret)
return MICRON_ON_DIE_UNSUPPORTED;
- ret = nand_get_features(chip, ONFI_FEATURE_ON_DIE_ECC, feature);
- if (ret < 0)
- return ret;
+ ret = nand_readid_op(chip, 0, id, sizeof(id));
+ if (ret)
+ return MICRON_ON_DIE_UNSUPPORTED;
- if (feature[0] & ONFI_FEATURE_ON_DIE_ECC_EN)
+ if (id[4] & MICRON_ID_ECC_ENABLED)
return MICRON_ON_DIE_MANDATORY;
/*