[PATCH 1/2] mtd: spi-nor: Add capability to disable flash quad mode
Tudor.Ambarus at microchip.com
Tudor.Ambarus at microchip.com
Thu Jul 2 07:07:43 EDT 2020
On 6/16/20 4:02 PM, Yicong Yang wrote:
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>
> Previous we didn't provide a way to disable the flash's quad mode.
> Which means we cannot do some cleanup works when to remove or
> poweroff the flash, like what set 4-byte address mode does in
> spi_nor_restore().
>
> Add the capability to disable the flash quad mode, by introducing
> an enable flag in the flash parameters quad_enable() hooks and
> related functions.
>
> Signed-off-by: Yicong Yang <yangyicong at hisilicon.com>
> Reviewed-by: Pratyush Yadav <p.yadav at ti.com>
> ---
> drivers/mtd/spi-nor/core.c | 55 +++++++++++++++++++++++++++++++---------------
> drivers/mtd/spi-nor/core.h | 10 ++++-----
> 2 files changed, 42 insertions(+), 23 deletions(-)
>
> diff --git a/drivers/mtd/spi-nor/core.c b/drivers/mtd/spi-nor/core.c
> index 0369d98..ad5498f 100644
> --- a/drivers/mtd/spi-nor/core.c
> +++ b/drivers/mtd/spi-nor/core.c
> @@ -1907,15 +1907,16 @@ static int spi_nor_is_locked(struct mtd_info *mtd, loff_t ofs, uint64_t len)
> }
>
> /**
> - * spi_nor_sr1_bit6_quad_enable() - Set the Quad Enable BIT(6) in the Status
> - * Register 1.
> + * spi_nor_sr1_bit6_quad_enable() - Set/Unset the Quad Enable BIT(6) in the
> + * Status Register 1.
> * @nor: pointer to a 'struct spi_nor'
> + * @enable: true to enter quad mode. false to leave quad mode.
s/enter/enable and s/leave/disable? s/quad mode/Quad Mode
> *
> * Bit 6 of the Status Register 1 is the QE bit for Macronix like QSPI memories.
> *
> * Return: 0 on success, -errno otherwise.
> */
> -int spi_nor_sr1_bit6_quad_enable(struct spi_nor *nor)
> +int spi_nor_sr1_bit6_quad_enable(struct spi_nor *nor, bool enable)
> {
> int ret;
>
> @@ -1923,45 +1924,58 @@ int spi_nor_sr1_bit6_quad_enable(struct spi_nor *nor)
> if (ret)
> return ret;
>
> - if (nor->bouncebuf[0] & SR1_QUAD_EN_BIT6)
> + if ((enable && (nor->bouncebuf[0] & SR1_QUAD_EN_BIT6)) ||
> + (!enable || !(nor->bouncebuf[0] & SR1_QUAD_EN_BIT6)))
there's a bug here, I think that you wanted:
(!enable && !(nor->bouncebuf[0] & SR1_QUAD_EN_BIT6))
> return 0;
>
> - nor->bouncebuf[0] |= SR1_QUAD_EN_BIT6;
> + if (enable)
> + nor->bouncebuf[0] |= SR1_QUAD_EN_BIT6;
> + else
> + nor->bouncebuf[0] &= ~SR1_QUAD_EN_BIT6;
>
> return spi_nor_write_sr1_and_check(nor, nor->bouncebuf[0]);
> }
>
> /**
> - * spi_nor_sr2_bit1_quad_enable() - set the Quad Enable BIT(1) in the Status
> - * Register 2.
> + * spi_nor_sr2_bit1_quad_enable() - set/unset the Quad Enable BIT(1) in the
> + * Status Register 2.
> * @nor: pointer to a 'struct spi_nor'.
> + * @enable: true to enter quad mode. false to leave quad mode.
ditto
> *
> * Bit 1 of the Status Register 2 is the QE bit for Spansion like QSPI memories.
> *
> * Return: 0 on success, -errno otherwise.
> */
> -int spi_nor_sr2_bit1_quad_enable(struct spi_nor *nor)
> +int spi_nor_sr2_bit1_quad_enable(struct spi_nor *nor, bool enable)
> {
> int ret;
>
> if (nor->flags & SNOR_F_NO_READ_CR)
> - return spi_nor_write_16bit_cr_and_check(nor, SR2_QUAD_EN_BIT1);
> + return spi_nor_write_16bit_cr_and_check(nor,
> + enable ? SR2_QUAD_EN_BIT1 : 0);
>
> ret = spi_nor_read_cr(nor, nor->bouncebuf);
> if (ret)
> return ret;
>
> - if (nor->bouncebuf[0] & SR2_QUAD_EN_BIT1)
> + if ((enable && (nor->bouncebuf[0] & SR2_QUAD_EN_BIT1)) ||
> + !(enable || (nor->bouncebuf[0] & SR2_QUAD_EN_BIT1)))
I am too finding the following line more readable. Would you change it?
(!enable && !(nor->bouncebuf[0] & SR2_QUAD_EN_BIT1))
> return 0;
>
> nor->bouncebuf[0] |= SR2_QUAD_EN_BIT1;
you forgot to drop this line
>
> + if (enable)
> + nor->bouncebuf[0] |= SR2_QUAD_EN_BIT1;
> + else
> + nor->bouncebuf[0] &= ~SR2_QUAD_EN_BIT1;
> +
> return spi_nor_write_16bit_cr_and_check(nor, nor->bouncebuf[0]);
> }
>
> /**
> - * spi_nor_sr2_bit7_quad_enable() - set QE bit in Status Register 2.
> + * spi_nor_sr2_bit7_quad_enable() - set/unset QE bit in Status Register 2.
> * @nor: pointer to a 'struct spi_nor'
> + * @enable: true to enter quad mode. false to leave quad mode.
ditto
> *
> * Set the Quad Enable (QE) bit in the Status Register 2.
> *
> @@ -1971,7 +1985,7 @@ int spi_nor_sr2_bit1_quad_enable(struct spi_nor *nor)
> *
> * Return: 0 on success, -errno otherwise.
> */
> -int spi_nor_sr2_bit7_quad_enable(struct spi_nor *nor)
> +int spi_nor_sr2_bit7_quad_enable(struct spi_nor *nor, bool enable)
> {
> u8 *sr2 = nor->bouncebuf;
> int ret;
> @@ -1981,11 +1995,15 @@ int spi_nor_sr2_bit7_quad_enable(struct spi_nor *nor)
> ret = spi_nor_read_sr2(nor, sr2);
> if (ret)
> return ret;
> - if (*sr2 & SR2_QUAD_EN_BIT7)
> + if ((enable && (*sr2 & SR2_QUAD_EN_BIT7)) ||
> + !(enable || (*sr2 & SR2_QUAD_EN_BIT7)))
(!enable && !(*sr2 & SR2_QUAD_EN_BIT7))
> return 0;
>
> /* Update the Quad Enable bit. */
> - *sr2 |= SR2_QUAD_EN_BIT7;
> + if (enable)
> + *sr2 |= SR2_QUAD_EN_BIT7;
> + else
> + *sr2 &= ~SR2_QUAD_EN_BIT7;
>
> ret = spi_nor_write_sr2(nor, sr2);
> if (ret)
> @@ -2898,12 +2916,13 @@ static int spi_nor_init_params(struct spi_nor *nor)
> }
>
> /**
> - * spi_nor_quad_enable() - enable Quad I/O if needed.
> + * spi_nor_quad_enable() - enable/disable Quad I/O if needed.
> * @nor: pointer to a 'struct spi_nor'
> + * @enable: true to enable quad mode. false to disable.
ditto
> *
> * Return: 0 on success, -errno otherwise.
> */
> -static int spi_nor_quad_enable(struct spi_nor *nor)
> +static int spi_nor_quad_enable(struct spi_nor *nor, bool enable)
> {
> if (!nor->params->quad_enable)
> return 0;
> @@ -2912,7 +2931,7 @@ static int spi_nor_quad_enable(struct spi_nor *nor)
> spi_nor_get_protocol_width(nor->write_proto) == 4))
> return 0;
>
> - return nor->params->quad_enable(nor);
> + return nor->params->quad_enable(nor, enable);
> }
>
> /**
> @@ -2936,7 +2955,7 @@ static int spi_nor_init(struct spi_nor *nor)
> {
> int err;
>
> - err = spi_nor_quad_enable(nor);
> + err = spi_nor_quad_enable(nor, true);
> if (err) {
> dev_dbg(nor->dev, "quad mode not supported\n");
> return err;
> diff --git a/drivers/mtd/spi-nor/core.h b/drivers/mtd/spi-nor/core.h
> index 6f2f6b2..222e0d3 100644
> --- a/drivers/mtd/spi-nor/core.h
> +++ b/drivers/mtd/spi-nor/core.h
> @@ -198,7 +198,7 @@ struct spi_nor_locking_ops {
> * higher index in the array, the higher priority.
> * @erase_map: the erase map parsed from the SFDP Sector Map Parameter
> * Table.
> - * @quad_enable: enables SPI NOR quad mode.
> + * @quad_enable: enables/disables SPI NOR quad mode.
> * @set_4byte_addr_mode: puts the SPI NOR in 4 byte addressing mode.
> * @convert_addr: converts an absolute address into something the flash
> * will understand. Particularly useful when pagesize is
> @@ -219,7 +219,7 @@ struct spi_nor_flash_parameter {
>
> struct spi_nor_erase_map erase_map;
>
> - int (*quad_enable)(struct spi_nor *nor);
> + int (*quad_enable)(struct spi_nor *nor, bool enable);
> int (*set_4byte_addr_mode)(struct spi_nor *nor, bool enable);
> u32 (*convert_addr)(struct spi_nor *nor, u32 addr);
> int (*setup)(struct spi_nor *nor, const struct spi_nor_hwcaps *hwcaps);
> @@ -406,9 +406,9 @@ int spi_nor_write_ear(struct spi_nor *nor, u8 ear);
> int spi_nor_wait_till_ready(struct spi_nor *nor);
> int spi_nor_lock_and_prep(struct spi_nor *nor);
> void spi_nor_unlock_and_unprep(struct spi_nor *nor);
> -int spi_nor_sr1_bit6_quad_enable(struct spi_nor *nor);
> -int spi_nor_sr2_bit1_quad_enable(struct spi_nor *nor);
> -int spi_nor_sr2_bit7_quad_enable(struct spi_nor *nor);
> +int spi_nor_sr1_bit6_quad_enable(struct spi_nor *nor, bool enable);
> +int spi_nor_sr2_bit1_quad_enable(struct spi_nor *nor, bool enable);
> +int spi_nor_sr2_bit7_quad_enable(struct spi_nor *nor, bool enable);
>
> int spi_nor_xread_sr(struct spi_nor *nor, u8 *sr);
> ssize_t spi_nor_read_data(struct spi_nor *nor, loff_t from, size_t len,
> --
> 2.8.1
>
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