Re: [PATCH v4 07/11] mtd: spi-nor: Favor the BFPT-parsed set_4byte_addr_mode method

[Tudor Ambarus]

On 3/22/23 06:40, Tudor Ambarus wrote:
> JESD216 SFDP defines in the BFPT standard methods to enter and exit the
> 4-Byte Address Mode. The flash parameters and settings that are retrieved
> from SFDP have higher precedence than the static initialized ones, because
> they should be more accurate and less error prone than those initialized
> statically. Favor the BFPT-parsed set_4byte_addr_mode method and use the
> generic core methods where possible.
> This patch may introduce regressions in case BFPT contains wrong data. The
> fix is to introduce a post_bfpt() fixup hook and update the wrong BFPT
> data.
> 
> Signed-off-by: Tudor Ambarus <tudor.ambarus@xxxxxxxxxx>
> Reviewed-by: Pratyush Yadav <p.yadav@xxxxxx>
> ---
>  drivers/mtd/spi-nor/core.c      | 7 ++++++-
>  drivers/mtd/spi-nor/macronix.c  | 8 +++++++-
>  drivers/mtd/spi-nor/micron-st.c | 6 ++++--
>  3 files changed, 17 insertions(+), 4 deletions(-)
> 
> diff --git a/drivers/mtd/spi-nor/core.c b/drivers/mtd/spi-nor/core.c
> index e212cc3c630d..2a08f8de97fa 100644
> --- a/drivers/mtd/spi-nor/core.c
> +++ b/drivers/mtd/spi-nor/core.c
> @@ -2533,6 +2533,8 @@ static void spi_nor_init_fixup_flags(struct spi_nor *nor)
>   */
>  static void spi_nor_late_init_params(struct spi_nor *nor)
>  {
> +	struct spi_nor_flash_parameter *params = nor->params;
> +
>  	if (nor->manufacturer && nor->manufacturer->fixups &&
>  	    nor->manufacturer->fixups->late_init)
>  		nor->manufacturer->fixups->late_init(nor);
> @@ -2540,6 +2542,10 @@ static void spi_nor_late_init_params(struct spi_nor *nor)
>  	if (nor->info->fixups && nor->info->fixups->late_init)
>  		nor->info->fixups->late_init(nor);
>  
> +	/* Default method kept for backward compatibility. */
> +	if (!params->set_4byte_addr_mode)
> +		params->set_4byte_addr_mode = spi_nor_set_4byte_addr_mode_brwr;
> +
>  	spi_nor_init_flags(nor);
>  	spi_nor_init_fixup_flags(nor);
>  
> @@ -2606,7 +2612,6 @@ static void spi_nor_init_default_params(struct spi_nor *nor)
>  	struct device_node *np = spi_nor_get_flash_node(nor);
>  
>  	params->quad_enable = spi_nor_sr2_bit1_quad_enable;
> -	params->set_4byte_addr_mode = spi_nor_set_4byte_addr_mode_brwr;
>  	params->otp.org = &info->otp_org;
>  
>  	/* Default to 16-bit Write Status (01h) Command */
> diff --git a/drivers/mtd/spi-nor/macronix.c b/drivers/mtd/spi-nor/macronix.c
> index 91a8fa7d4512..075a26945f2d 100644
> --- a/drivers/mtd/spi-nor/macronix.c
> +++ b/drivers/mtd/spi-nor/macronix.c
> @@ -105,11 +105,17 @@ static const struct flash_info macronix_nor_parts[] = {
>  static void macronix_nor_default_init(struct spi_nor *nor)
>  {
>  	nor->params->quad_enable = spi_nor_sr1_bit6_quad_enable;
> -	nor->params->set_4byte_addr_mode = spi_nor_set_4byte_addr_mode_en4b_ex4b;
> +}
> +
> +static void macronix_nor_late_init(struct spi_nor *nor)
> +{
> +	if (!nor->params->set_4byte_addr_mode)
> +		nor->params->set_4byte_addr_mode = spi_nor_set_4byte_addr_mode_en4b_ex4b;
>  }
>  
>  static const struct spi_nor_fixups macronix_nor_fixups = {
>  	.default_init = macronix_nor_default_init,
> +	.late_init = macronix_nor_late_init,
>  };
>  
>  const struct spi_nor_manufacturer spi_nor_macronix = {
> diff --git a/drivers/mtd/spi-nor/micron-st.c b/drivers/mtd/spi-nor/micron-st.c
> index a75f0f4e1c38..4d5333b14807 100644
> --- a/drivers/mtd/spi-nor/micron-st.c
> +++ b/drivers/mtd/spi-nor/micron-st.c
> @@ -425,13 +425,15 @@ static void micron_st_nor_default_init(struct spi_nor *nor)
>  	nor->flags |= SNOR_F_HAS_LOCK;
>  	nor->flags &= ~SNOR_F_HAS_16BIT_SR;
>  	nor->params->quad_enable = NULL;
> -	nor->params->set_4byte_addr_mode = spi_nor_set_4byte_addr_mode_wren_en4b_ex4b;
>  }
>  
>  static void micron_st_nor_late_init(struct spi_nor *nor)
>  {
> +	struct spi_nor_flash_parameter *params = nor->params;
> +
>  	if (nor->info->mfr_flags & USE_FSR)
> -		nor->params->ready = micron_st_nor_ready;
> +		params->ready = micron_st_nor_ready;
> +	params->set_4byte_addr_mode = spi_nor_set_4byte_addr_mode_wren_en4b_ex4b;

should have been:
	if (!params->set_4byte_addr_mode)
		params->set_4byte_addr_mode = spi_nor_set_4byte_addr_mode_wren_en4b_ex4b;


>  }
>  
>  static const struct spi_nor_fixups micron_st_nor_fixups = {