[PATCH v16 14/15] mtd: spi-nor: spansion: add support for Cypress Semper flash

Pratyush Yadav p.yadav at ti.com
Mon Nov 9 06:45:43 EST 2020


On 07/11/20 01:28PM, Vignesh Raghavendra wrote:
> Hi,
> 
> [...]
> 
> On 10/5/20 9:01 PM, Pratyush Yadav wrote:
> > +static int spi_nor_cypress_octal_dtr_enable(struct spi_nor *nor, bool enable)
> > +{
> > +	struct spi_mem_op op;
> > +	u8 *buf = nor->bouncebuf;
> > +	int ret;
> > +
> > +	if (enable) {
> > +		/* Use 24 dummy cycles for memory array reads. */
> > +		ret = spi_nor_write_enable(nor);
> > +		if (ret)
> > +			return ret;
> > +
> > +		*buf = SPINOR_REG_CYPRESS_CFR2V_MEMLAT_11_24;
> > +		op = (struct spi_mem_op)
> > +			SPI_MEM_OP(SPI_MEM_OP_CMD(SPINOR_OP_WR_ANY_REG, 1),
> > +				   SPI_MEM_OP_ADDR(3, SPINOR_REG_CYPRESS_CFR2V,
> > +						   1),
> > +				   SPI_MEM_OP_NO_DUMMY,
> > +				   SPI_MEM_OP_DATA_OUT(1, buf, 1));
> > +
> > +		ret = spi_mem_exec_op(nor->spimem, &op);
> > +		if (ret)
> > +			return ret;
> > +
> > +		ret = spi_nor_wait_till_ready(nor);
> > +		if (ret)
> > +			return ret;
> > +
> > +		nor->read_dummy = 24;
> > +	}
> > +
> > +	/* Set/unset the octal and DTR enable bits. */
> > +	ret = spi_nor_write_enable(nor);
> > +	if (ret)
> > +		return ret;
> > +
> > +	if (enable)
> > +		*buf = SPINOR_REG_CYPRESS_CFR5V_OCT_DTR_EN;
> > +	else
> > +		*buf = SPINOR_REG_CYPRESS_CFR5V_OCT_DTR_DS;
> > +
> > +	op = (struct spi_mem_op)
> > +		SPI_MEM_OP(SPI_MEM_OP_CMD(SPINOR_OP_WR_ANY_REG, 1),
> > +			   SPI_MEM_OP_ADDR(enable ? 3 : 4,
> > +					   SPINOR_REG_CYPRESS_CFR5V,
> > +					   1),
> > +			   SPI_MEM_OP_NO_DUMMY,
> > +			   SPI_MEM_OP_DATA_OUT(1, buf, 1));
> > +
> > +	if (!enable)
> > +		spi_nor_spimem_setup_op(nor, &op, SNOR_PROTO_8_8_8_DTR);
> > +
> > +	ret = spi_mem_exec_op(nor->spimem, &op);
> > +	if (ret)
> > +		return ret;
> > +
> > +	/* Give some time for the mode change to take place. */
> > +	usleep_range(1000, 1500);
> > +
> 
> This delay is no longer needed right? I can drop it while applying, if
> you confirm.

Yes, this delay is not needed. Please drop it while applying.
 
> Tudor: Could you provide your R-by?
> 
> Regards
> Vignesh

-- 
Regards,
Pratyush Yadav
Texas Instruments India



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