2018-02-14 19:59:19

by KOBAYASHI Yoshitake

Subject: [PATCH -next v4] mtd: nand: toshiba: Retrieve ECC requirements from extended ID

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: KOBAYASHI Yoshitake <[email protected]>
---
drivers/mtd/nand/nand_toshiba.c | 26 ++++++++++++++++++++++++++
1 file changed, 26 insertions(+)

diff --git a/drivers/mtd/nand/nand_toshiba.c b/drivers/mtd/nand/nand_toshiba.c
index 57df857..ab43f02 100644
--- a/drivers/mtd/nand/nand_toshiba.c
+++ b/drivers/mtd/nand/nand_toshiba.c
@@ -35,6 +35,32 @@ 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)
--
2.7.4

2018-02-14 19:17:09

by Boris Brezillon

Subject: Re: [PATCH -next v4] mtd: nand: toshiba: Retrieve ECC requirements from extended ID

-linux-mmc
+linux-mtd

On Thu, 15 Feb 2018 00:35:06 +0900
KOBAYASHI Yoshitake <[email protected]> wrote:

> 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.

This version looks good to me.

>
> Signed-off-by: KOBAYASHI Yoshitake <[email protected]>
> ---
> drivers/mtd/nand/nand_toshiba.c | 26 ++++++++++++++++++++++++++
> 1 file changed, 26 insertions(+)
>
> diff --git a/drivers/mtd/nand/nand_toshiba.c b/drivers/mtd/nand/nand_toshiba.c
> index 57df857..ab43f02 100644
> --- a/drivers/mtd/nand/nand_toshiba.c
> +++ b/drivers/mtd/nand/nand_toshiba.c
> @@ -35,6 +35,32 @@ 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)



--
Boris Brezillon, Bootlin (formerly Free Electrons)
Embedded Linux and Kernel engineering
http://bootlin.com

2018-02-14 20:13:50

by Boris Brezillon

Subject: Re: [PATCH -next v4] mtd: nand: toshiba: Retrieve ECC requirements from extended ID

On Wed, 14 Feb 2018 20:15:41 +0100
Boris Brezillon <[email protected]> wrote:

> -linux-mmc
> +linux-mtd
>
> On Thu, 15 Feb 2018 00:35:06 +0900
> KOBAYASHI Yoshitake <[email protected]> wrote:
>
> > 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.
>
> This version looks good to me.
>

Applied.

Thanks,

Boris

> >
> > Signed-off-by: KOBAYASHI Yoshitake <[email protected]>
> > ---
> > drivers/mtd/nand/nand_toshiba.c | 26 ++++++++++++++++++++++++++
> > 1 file changed, 26 insertions(+)
> >
> > diff --git a/drivers/mtd/nand/nand_toshiba.c b/drivers/mtd/nand/nand_toshiba.c
> > index 57df857..ab43f02 100644
> > --- a/drivers/mtd/nand/nand_toshiba.c
> > +++ b/drivers/mtd/nand/nand_toshiba.c
> > @@ -35,6 +35,32 @@ 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)
>
>
>



--
Boris Brezillon, Bootlin (formerly Free Electrons)
Embedded Linux and Kernel engineering
http://bootlin.com