On Fri, 22 Jun 2018 13:28:35 +1200
Chris Packham <[email protected]> wrote:
> Some Micron NAND chips have on-die ECC forceably enabled. The detect
^ Detect ?
> these based on chip ID as there seems to be no other way of
> distinguishing these chips from those that have optional support for
> on-die ECC.
>
> When a chip with mandatory on-die ECC is detected change the current ECC
> mode to on-die.
That part is no longer true.
>
> Signed-off-by: Chris Packham <[email protected]>
With the commit message fixed:
Reviewed-by: Boris Brezillon <[email protected]>
> ---
>
> Notes:
> Changes in v4:
> - New
> Changes in v5:
> - fail if on-die ECC is mandatory and the current ecc.mode is not
> NAND_ECC_ON_DIE.
>
> drivers/mtd/nand/raw/nand_micron.c | 16 +++++++++++++++-
> 1 file changed, 15 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/mtd/nand/raw/nand_micron.c
> b/drivers/mtd/nand/raw/nand_micron.c
> index f83053562925..35fa6880a799 100644
> --- a/drivers/mtd/nand/raw/nand_micron.c
> +++ b/drivers/mtd/nand/raw/nand_micron.c
> @@ -255,6 +255,14 @@ enum {
> MICRON_ON_DIE_MANDATORY,
> };
>
> +/*
> + * These parts are known to have on-die ECC forceably enabled
> + */
> +static u8 micron_on_die_ecc[] = {
> + 0xd1, /* MT29F1G08ABAFA */
> + 0xa1, /* MT29F1G08ABBFA */
> +};
> +
> /*
> * 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
> @@ -269,6 +277,11 @@ static int micron_supports_on_die_ecc(struct nand_chip
> *chip)
> {
> u8 feature[ONFI_SUBFEATURE_PARAM_LEN] = { 0, };
> int ret;
> + int i;
> +
> + for (i = 0; i < ARRAY_SIZE(micron_on_die_ecc); i++)
> + if (chip->id.data[1] == micron_on_die_ecc[i])
> + return MICRON_ON_DIE_MANDATORY;
>
> if (!chip->parameters.onfi.version)
> return MICRON_ON_DIE_UNSUPPORTED;
> @@ -322,7 +335,8 @@ static int micron_nand_init(struct nand_chip *chip)
>
> ondie = micron_supports_on_die_ecc(chip);
>
> - if (ondie == MICRON_ON_DIE_MANDATORY) {
> + if (ondie == MICRON_ON_DIE_MANDATORY &&
> + chip->ecc.mode != NAND_ECC_ON_DIE) {
> pr_err("On-die ECC forcefully enabled, not supported\n");
> return -EINVAL;
> }
