Re: [PATCH v4 3/3] mtd: spi-nor: Add support for IS25LX256 operating in 1S-8S-8S octal read mode

[Michael Walle]

Am 2022-12-02 14:55, schrieb Nathan Barrett-Morrison:
> This adds the IS25LX256 chip into the ISSI flash_info parts table
>
> Signed-off-by: Nathan Barrett-Morrison <nathan.morrison@xxxxxxxxxxx>
> ---
>  drivers/mtd/spi-nor/issi.c | 32 ++++++++++++++++++++++++++++++++
>  1 file changed, 32 insertions(+)
>
> diff --git a/drivers/mtd/spi-nor/issi.c b/drivers/mtd/spi-nor/issi.c
> index 89a66a19d754..362bc3603d8f 100644
> --- a/drivers/mtd/spi-nor/issi.c
> +++ b/drivers/mtd/spi-nor/issi.c
> @@ -29,6 +29,35 @@ static const struct spi_nor_fixups is25lp256_fixups 
> = {
>  	.post_bfpt = is25lp256_post_bfpt_fixups,
>  };
>
> +static int
> +is25lx256_post_bfpt_fixups(struct spi_nor *nor,
> +			   const struct sfdp_parameter_header *bfpt_header,
> +			   const struct sfdp_bfpt *bfpt)
> +{
> +	/*
> +	 * IS25LX256 supports both 1S-1S-8S and 1S-8S-8S.
> +	 * However, the BFPT does not contain any information denoting this
> +	 * functionality, so the proper fast read opcodes are never setup.
> +	 * We're correcting this issue via the fixup below.  Page program
> +	 * commands are detected and setup properly via the 4BAIT lookup.
> +	 */
> +	params->hwcaps.mask |= SNOR_HWCAPS_READ_1_1_8;
> +	spi_nor_set_read_settings(&params->reads[SNOR_CMD_READ_1_1_8],
> +				  0, 8, SPINOR_OP_READ_1_1_8,
> +				  SNOR_PROTO_1_1_8);
> +
> +	params->hwcaps.mask |= SNOR_HWCAPS_READ_1_8_8;
> +	spi_nor_set_read_settings(&params->reads[SNOR_CMD_READ_1_8_8],
> +				  0, 16, SPINOR_OP_READ_1_8_8,
> +				  SNOR_PROTO_1_8_8);
> +
> +	return 0;
> +}
> +
> +static const struct spi_nor_fixups is25lx256_fixups = {
> +	.post_bfpt = is25lx256_post_bfpt_fixups,
> +};
> +
>  static void pm25lv_nor_late_init(struct spi_nor *nor)
>  {
>  	struct spi_nor_erase_map *map = &nor->params->erase_map;
> @@ -74,6 +103,9 @@ static const struct flash_info issi_nor_parts[] = {
>  		NO_SFDP_FLAGS(SECT_4K | SPI_NOR_DUAL_READ | SPI_NOR_QUAD_READ)
>  		FIXUP_FLAGS(SPI_NOR_4B_OPCODES)
>  		.fixups = &is25lp256_fixups },
> +	{ "is25lx256", INFO(0x9d5a19, 0, 0, 0)
> +		PARSE_SFDP
> +		.fixups = &is25lx256_fixups },

Very nice!

Subject is slightly wrong because you fix up the BFPT to get
correct 1-1-8 and 1-8-8 read modes.

With that fixed:
Reviewed-by: Michael Walle <michael@xxxxxxxx>