From: Michael Trimarchi <mich...@amarulasolutions.com>
Upstream linux commit fb3bff5b407e58.
This patch enables support to read the ECC strength and size from the
NAND flash using Toshiba Memory SLC NAND extended-ID. This patch is
based on the information of the 6th ID byte of the Toshiba Memory SLC
NAND.
Signed-off-by: Michael Trimarchi <mich...@amarulasolutions.com>
Signed-off-by: Dario Binacchi <dario.binac...@amarulasolutions.com>
---
Changes in v3:
- Use commit sha1 with 13 digits.
Changes in v2:
- Use short-commit form
- Remove linux info. Uboot seems that backport without add this
extra information.
drivers/mtd/nand/raw/nand_toshiba.c | 26 ++++++++++++++++++++++++++
1 file changed, 26 insertions(+)
diff --git a/drivers/mtd/nand/raw/nand_toshiba.c
b/drivers/mtd/nand/raw/nand_toshiba.c
index f7426fa59f51..99dc44df671a 100644
--- a/drivers/mtd/nand/raw/nand_toshiba.c
+++ b/drivers/mtd/nand/raw/nand_toshiba.c
@@ -37,6 +37,32 @@ static void toshiba_nand_decode_id(struct nand_chip *chip)
(chip->id.data[5] & 0x7) == 0x6 /* 24nm */ &&
!(chip->id.data[4] & 0x80) /* !BENAND */)
mtd->oobsize = 32 * mtd->writesize >> 9;
+
+ /*
+ * Extract ECC requirements from 6th id byte.
+ * For Toshiba SLC, ecc requrements are as follows:
+ * - 43nm: 1 bit ECC for each 512Byte is required.
+ * - 32nm: 4 bit ECC for each 512Byte is required.
+ * - 24nm: 8 bit ECC for each 512Byte is required.
+ */
+ if (chip->id.len >= 6 && nand_is_slc(chip)) {
+ chip->ecc_step_ds = 512;
+ switch (chip->id.data[5] & 0x7) {
+ case 0x4:
+ chip->ecc_strength_ds = 1;
+ break;
+ case 0x5:
+ chip->ecc_strength_ds = 4;
+ break;
+ case 0x6:
+ chip->ecc_strength_ds = 8;
+ break;
+ default:
+ WARN(1, "Could not get ECC info");
+ chip->ecc_step_ds = 0;
+ break;
+ }
+ }
}
static int toshiba_nand_init(struct nand_chip *chip)
--
2.32.0
