Re: [PATCH -next v4] mtd: nand: toshiba: Retrieve ECC requirements from extended ID
From: Boris Brezillon
Date: Wed Feb 14 2018 - 14:29:38 EST
On Wed, 14 Feb 2018 20:15:41 +0100
Boris Brezillon <boris.brezillon@xxxxxxxxxxx> wrote:
> -linux-mmc
> +linux-mtd
>
> On Thu, 15 Feb 2018 00:35:06 +0900
> KOBAYASHI Yoshitake <yoshitake.kobayashi@xxxxxxxxxxxxx> 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 <yoshitake.kobayashi@xxxxxxxxxxxxx>
> > ---
> > 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