Re: [PATCH v3 1/5] mtd: rawnand: brcmnand: Fix ECC level field setting for v7.2 controller

[Miquel Raynal <miquel.raynal@bootlin.com>]

Hi William,

william.zhang@broadcom.com wrote on Tue, 27 Jun 2023 12:37:34 -0700:

> v7.2 controller has different ECC level field size and shift in the acc
> control register than its predecessor and successor controller. It needs
> to be set specifically.
> 
> Fixes: decba6d47869 ("mtd: brcmnand: Add v7.2 controller support")
> Signed-off-by: William Zhang <william.zhang@broadcom.com>
> Reviewed-by: Florian Fainelli <florian.fainelli@broadcom.com>
> 
> ---
> 
> Changes in v3: None
> Changes in v2:
> - Use driver static data for ECC level shift
> 
>  drivers/mtd/nand/raw/brcmnand/brcmnand.c | 74 +++++++++++++-----------
>  1 file changed, 41 insertions(+), 33 deletions(-)
> 
> diff --git a/drivers/mtd/nand/raw/brcmnand/brcmnand.c b/drivers/mtd/nand/raw/brcmnand/brcmnand.c
> index 2e9c2e2d9c9f..69709419516a 100644
> --- a/drivers/mtd/nand/raw/brcmnand/brcmnand.c
> +++ b/drivers/mtd/nand/raw/brcmnand/brcmnand.c
> @@ -272,6 +272,7 @@ struct brcmnand_controller {
>  	const unsigned int	*page_sizes;
>  	unsigned int		page_size_shift;
>  	unsigned int		max_oob;
> +	u32			ecc_level_shift;
>  	u32			features;
>  
>  	/* for low-power standby/resume only */
> @@ -596,6 +597,34 @@ enum {
>  	INTFC_CTLR_READY		= BIT(31),
>  };
>  
> +/***********************************************************************
> + * NAND ACC CONTROL bitfield
> + *
> + * Some bits have remained constant throughout hardware revision, while
> + * others have shifted around.
> + ***********************************************************************/
> +
> +/* Constant for all versions (where supported) */
> +enum {
> +	/* See BRCMNAND_HAS_CACHE_MODE */
> +	ACC_CONTROL_CACHE_MODE				= BIT(22),
> +
> +	/* See BRCMNAND_HAS_PREFETCH */
> +	ACC_CONTROL_PREFETCH				= BIT(23),
> +
> +	ACC_CONTROL_PAGE_HIT				= BIT(24),
> +	ACC_CONTROL_WR_PREEMPT				= BIT(25),
> +	ACC_CONTROL_PARTIAL_PAGE			= BIT(26),
> +	ACC_CONTROL_RD_ERASED				= BIT(27),
> +	ACC_CONTROL_FAST_PGM_RDIN			= BIT(28),
> +	ACC_CONTROL_WR_ECC				= BIT(30),
> +	ACC_CONTROL_RD_ECC				= BIT(31),
> +
> +	ACC_CONTROL_ECC_SHIFT				= 16,
> +	/* Only for v7.2 */
> +	ACC_CONTROL_ECC_EXT_SHIFT			= 13,
> +};

These do not look like they fit the purpose of enums. At least keep
these two last definitions outside like before (you can rename them, I
don't mind).

LGTM otherwise.

> +
>  static inline bool brcmnand_non_mmio_ops(struct brcmnand_controller *ctrl)
>  {
>  #if IS_ENABLED(CONFIG_MTD_NAND_BRCMNAND_BCMA)
> @@ -737,6 +766,12 @@ static int brcmnand_revision_init(struct brcmnand_controller *ctrl)
>  	else if (of_property_read_bool(ctrl->dev->of_node, "brcm,nand-has-wp"))
>  		ctrl->features |= BRCMNAND_HAS_WP;
>  
> +	/* v7.2 has different ecc level shift in the acc register */
> +	if (ctrl->nand_version == 0x0702)
> +		ctrl->ecc_level_shift = ACC_CONTROL_ECC_EXT_SHIFT;
> +	else
> +		ctrl->ecc_level_shift = ACC_CONTROL_ECC_SHIFT;
> +
>  	return 0;
>  }
>  
> @@ -931,30 +966,6 @@ static inline int brcmnand_cmd_shift(struct brcmnand_controller *ctrl)
>  	return 0;
>  }
>  
> -/***********************************************************************
> - * NAND ACC CONTROL bitfield
> - *
> - * Some bits have remained constant throughout hardware revision, while
> - * others have shifted around.
> - ***********************************************************************/
> -
> -/* Constant for all versions (where supported) */
> -enum {
> -	/* See BRCMNAND_HAS_CACHE_MODE */
> -	ACC_CONTROL_CACHE_MODE				= BIT(22),
> -
> -	/* See BRCMNAND_HAS_PREFETCH */
> -	ACC_CONTROL_PREFETCH				= BIT(23),
> -
> -	ACC_CONTROL_PAGE_HIT				= BIT(24),
> -	ACC_CONTROL_WR_PREEMPT				= BIT(25),
> -	ACC_CONTROL_PARTIAL_PAGE			= BIT(26),
> -	ACC_CONTROL_RD_ERASED				= BIT(27),
> -	ACC_CONTROL_FAST_PGM_RDIN			= BIT(28),
> -	ACC_CONTROL_WR_ECC				= BIT(30),
> -	ACC_CONTROL_RD_ECC				= BIT(31),
> -};
> -
>  static inline u32 brcmnand_spare_area_mask(struct brcmnand_controller *ctrl)
>  {
>  	if (ctrl->nand_version == 0x0702)
> @@ -967,18 +978,15 @@ static inline u32 brcmnand_spare_area_mask(struct brcmnand_controller *ctrl)
>  		return GENMASK(4, 0);
>  }
>  
> -#define NAND_ACC_CONTROL_ECC_SHIFT	16
> -#define NAND_ACC_CONTROL_ECC_EXT_SHIFT	13
> -
>  static inline u32 brcmnand_ecc_level_mask(struct brcmnand_controller *ctrl)
>  {
>  	u32 mask = (ctrl->nand_version >= 0x0600) ? 0x1f : 0x0f;
>  
> -	mask <<= NAND_ACC_CONTROL_ECC_SHIFT;
> +	mask <<= ACC_CONTROL_ECC_SHIFT;
>  
>  	/* v7.2 includes additional ECC levels */
> -	if (ctrl->nand_version >= 0x0702)
> -		mask |= 0x7 << NAND_ACC_CONTROL_ECC_EXT_SHIFT;
> +	if (ctrl->nand_version == 0x0702)
> +		mask |= 0x7 << ACC_CONTROL_ECC_EXT_SHIFT;
>  
>  	return mask;
>  }
> @@ -992,8 +1000,8 @@ static void brcmnand_set_ecc_enabled(struct brcmnand_host *host, int en)
>  
>  	if (en) {
>  		acc_control |= ecc_flags; /* enable RD/WR ECC */
> -		acc_control |= host->hwcfg.ecc_level
> -			       << NAND_ACC_CONTROL_ECC_SHIFT;
> +		acc_control &= ~brcmnand_ecc_level_mask(ctrl);
> +		acc_control |= host->hwcfg.ecc_level << ctrl->ecc_level_shift;
>  	} else {
>  		acc_control &= ~ecc_flags; /* disable RD/WR ECC */
>  		acc_control &= ~brcmnand_ecc_level_mask(ctrl);
> @@ -2561,7 +2569,7 @@ static int brcmnand_set_cfg(struct brcmnand_host *host,
>  	tmp &= ~brcmnand_ecc_level_mask(ctrl);
>  	tmp &= ~brcmnand_spare_area_mask(ctrl);
>  	if (ctrl->nand_version >= 0x0302) {
> -		tmp |= cfg->ecc_level << NAND_ACC_CONTROL_ECC_SHIFT;
> +		tmp |= cfg->ecc_level << ctrl->ecc_level_shift;
>  		tmp |= cfg->spare_area_size;
>  	}
>  	nand_writereg(ctrl, acc_control_offs, tmp);


Thanks,
Miquèl