RE: [EXT] [PATCH] mtd: spinand: micron: add support for MT29F2G01AAAED

[Shivamurthy Shastri (sshivamurthy)]

Hi Thirumalesha,

> 
> The MT29F2G01AAAED is a single die, 2Gb Micron SPI NAND Flash with 4-bit
> ECC
> 
> Signed-off-by: Thirumalesha Narasimhappa <nthirumalesha7@xxxxxxxxx>
> ---
>  drivers/mtd/nand/spi/micron.c | 77 +++++++++++++++++++++++++++++++++++
>  1 file changed, 77 insertions(+)
> 
> diff --git a/drivers/mtd/nand/spi/micron.c b/drivers/mtd/nand/spi/micron.c
> index 5d370cfcdaaa..7e0b61d7b90f 100644
> --- a/drivers/mtd/nand/spi/micron.c
> +++ b/drivers/mtd/nand/spi/micron.c
> @@ -17,6 +17,7 @@
>  #define MICRON_STATUS_ECC_1TO3_BITFLIPS	(1 << 4)
>  #define MICRON_STATUS_ECC_4TO6_BITFLIPS	(3 << 4)
>  #define MICRON_STATUS_ECC_7TO8_BITFLIPS	(5 << 4)

It is better to add comment here, like

/* For Micron  MT29F2G01AAAED Device */

> +#define MICRON_STATUS_ECC_1TO4_BITFLIPS	(1 << 4)
> 
>  #define MICRON_CFG_CR			BIT(0)
> 
> @@ -44,6 +45,19 @@ static SPINAND_OP_VARIANTS(update_cache_variants,
>  		SPINAND_PROG_LOAD_X4(false, 0, NULL, 0),
>  		SPINAND_PROG_LOAD(false, 0, NULL, 0));
> 
> +/* Micron  MT29F2G01AAAED Device */
> +static SPINAND_OP_VARIANTS(read_cache_variants_mt29f2g01aaaed,
> +		SPINAND_PAGE_READ_FROM_CACHE_X4_OP(0, 1, NULL, 0),
> +		SPINAND_PAGE_READ_FROM_CACHE_X2_OP(0, 1, NULL, 0),
> +		SPINAND_PAGE_READ_FROM_CACHE_OP(true, 0, 1, NULL, 0),
> +		SPINAND_PAGE_READ_FROM_CACHE_OP(false, 0, 1, NULL, 0));
> +
> +static SPINAND_OP_VARIANTS(write_cache_variants_mt29f2g01aaaed,
> +		SPINAND_PROG_LOAD(true, 0, NULL, 0));
> +
> +static SPINAND_OP_VARIANTS(update_cache_variants_mt29f2g01aaaed,
> +		SPINAND_PROG_LOAD(false, 0, NULL, 0));
> +
>  static int micron_8_ooblayout_ecc(struct mtd_info *mtd, int section,
>  				  struct mtd_oob_region *region)
>  {
> @@ -69,11 +83,41 @@ static int micron_8_ooblayout_free(struct mtd_info
> *mtd, int section,
>  	return 0;
>  }
> 
> +static int mt29f2g01aaaed_ooblayout_ecc(struct mtd_info *mtd, int section,
> +					struct mtd_oob_region *region)
> +{
> +	if (section >= 4)
> +		return -ERANGE;
> +
> +	region->offset = (section * 16) + 8;
> +	region->length = 8;
> +
> +	return 0;
> +}
> +
> +static int mt29f2g01aaaed_ooblayout_free(struct mtd_info *mtd, int section,
> +					 struct mtd_oob_region *region)
> +{
> +	if (section >= 4)
> +		return -ERANGE;
> +
> +	/* Reserve 2 bytes for the BBM. */
> +	region->offset = (section * 16) + 2;
> +	region->length = 6;
> +
> +	return 0;
> +}
> +
>  static const struct mtd_ooblayout_ops micron_8_ooblayout = {
>  	.ecc = micron_8_ooblayout_ecc,
>  	.free = micron_8_ooblayout_free,
>  };
> 
> +static const struct mtd_ooblayout_ops mt29f2g01aaaed_ooblayout = {
> +	.ecc = mt29f2g01aaaed_ooblayout_ecc,
> +	.free = mt29f2g01aaaed_ooblayout_free,
> +};
> +
>  static int micron_select_target(struct spinand_device *spinand,
>  				unsigned int target)
>  {
> @@ -114,6 +158,27 @@ static int micron_8_ecc_get_status(struct
> spinand_device *spinand,
>  	return -EINVAL;
>  }
> 
> +static int mt29f2g01aaaed_ecc_get_status(struct spinand_device *spinand,
> +					 u8 status)
> +{
> +	switch (status & MICRON_STATUS_ECC_MASK) {
> +	case STATUS_ECC_NO_BITFLIPS:
> +		return 0;
> +
> +	case STATUS_ECC_UNCOR_ERROR:
> +		return -EBADMSG;
> +
> +	/* 1 to 4-bit error detected and corrected */
> +	case MICRON_STATUS_ECC_1TO4_BITFLIPS:
> +		return 4;
> +
> +	default:
> +		break;
> +	}
> +
> +	return -EINVAL;
> +}
> +
>  static const struct spinand_info micron_spinand_table[] = {
>  	/* M79A 2Gb 3.3V */
>  	SPINAND_INFO("MT29F2G01ABAGD",
> @@ -217,6 +282,18 @@ static const struct spinand_info
> micron_spinand_table[] = {
>  		     SPINAND_ECCINFO(&micron_8_ooblayout,
>  				     micron_8_ecc_get_status),
>  		     SPINAND_SELECT_TARGET(micron_select_target)),
> +	/* M70A 2Gb 3.3V */

This should be M69A.

> +	SPINAND_INFO("MT29F2G01AAAED",
> +
> SPINAND_ID(SPINAND_READID_METHOD_OPCODE_DUMMY, 0x9F),
> +		     NAND_MEMORG(1, 2048, 256, 64, 2048, 80, 2, 1, 1),
> +		     NAND_ECCREQ(4, 512),
> +
> SPINAND_INFO_OP_VARIANTS(&read_cache_variants_mt29f2g01aaaed,
> +
> &write_cache_variants_mt29f2g01aaaed,
> +
> &update_cache_variants_mt29f2g01aaaed),
> +		     0,
> +		     SPINAND_ECCINFO(&mt29f2g01aaaed_ooblayout,
> +				     mt29f2g01aaaed_ecc_get_status),
> +		     SPINAND_SELECT_TARGET(micron_select_target)),

This device doesn't have multiple targets, you can remove micron_select_target.

>  };
> 
>  static int micron_spinand_init(struct spinand_device *spinand)
> --
> 2.17.1

Thanks,
Shiva