[PATCH v3 5/6] mtd: spi-nor: spansion: Add status check for multi-die parts

[Pratyush Yadav]

On 12/03/21 06:44PM, tkuw584924 at gmail.com wrote:
> From: Takahiro Kuwano <Takahiro.Kuwano at infineon.com>
> 
> The multi-die package parts from Spansion/Cypress require to check
> the status register value in each die to detemine the device is
> ready. This patch adds a helper that queries status of each die by
> Read Any Register command. The device specific ->ready() hook will
> call this helper with the number of dummy cycles and die size.
> 
> Signed-off-by: Takahiro Kuwano <Takahiro.Kuwano at infineon.com>
> ---
> Changes in v3:
>   - New in v3
> 
>  drivers/mtd/spi-nor/spansion.c | 46 ++++++++++++++++++++++++++++++++++
>  1 file changed, 46 insertions(+)
> 
> diff --git a/drivers/mtd/spi-nor/spansion.c b/drivers/mtd/spi-nor/spansion.c
> index b5b5df4836c6..5742212fde2e 100644
> --- a/drivers/mtd/spi-nor/spansion.c
> +++ b/drivers/mtd/spi-nor/spansion.c
> @@ -10,6 +10,7 @@
>  
>  #define SPINOR_OP_RD_ANY_REG			0x65	/* Read any register */
>  #define SPINOR_OP_WR_ANY_REG			0x71	/* Write any register */
> +#define SPINOR_REG_CYPRESS_STR1V		0x00800000
>  #define SPINOR_REG_CYPRESS_CFR1V		0x00800002
>  #define SPINOR_REG_CYPRESS_CFR1V_QUAD_EN	BIT(1)	/* Quad Enable */
>  #define SPINOR_REG_CYPRESS_CFR2V		0x00800003
> @@ -179,6 +180,51 @@ static int spansion_quad_enable_volatile(struct spi_nor *nor, u8 reg_dummy,
>  	return 0;
>  }
>  
> +/**
> + * spansion_mdp_ready() - Query the Status Register via Read Any Register
> + *                        command for multi-die package parts that do not
> + *                        support legacy RDSR(05h)

Same comment about the use of "legacy".

> + * @nor:	pointer to 'struct spi_nor'.
> + * @reg_dummy:	number of dummy cycles for register read
> + * @die_size:	size of each die to determine the number of dies
> + *
> + * Return: 1 if ready, 0 if not ready, -errno on errors.
> + */
> +static int spansion_mdp_ready(struct spi_nor *nor, u8 reg_dummy, u32 die_size)
> +{
> +	int ret;
> +	u32 base;
> +	u8 sr;
> +
> +	for (base = 0; base < nor->params->size; base += die_size) {
> +		ret = spansion_read_any_reg(nor,
> +					    base + SPINOR_REG_CYPRESS_STR1V,
> +					    reg_dummy, &sr);
> +		if (ret)
> +			return ret;
> +
> +		if (sr & (SR_E_ERR | SR_P_ERR)) {
> +			if (sr & SR_E_ERR)
> +				dev_err(nor->dev, "Erase Error occurred\n");
> +			else
> +				dev_err(nor->dev, "Programming Error occurred\n");
> +
> +			spi_nor_clear_sr(nor);

This will clear the error flags on all dies. Ok.

> +
> +			ret = spi_nor_write_disable(nor);
> +			if (ret)
> +				return ret;
> +
> +			return -EIO;
> +		}
> +
> +		if (sr & SR_WIP)
> +			return 0;
> +	}
> +
> +	return 1;
> +}
> +
>  /**
>   * spi_nor_cypress_octal_dtr_enable() - Enable octal DTR on Cypress flashes.
>   * @nor:		pointer to a 'struct spi_nor'

Reviewed-by: Pratyush Yadav <p.yadav at ti.com>

-- 
Regards,
Pratyush Yadav
Texas Instruments Inc.