Commit 981a8d60 authored by Tudor Ambarus's avatar Tudor Ambarus Committed by Vignesh Raghavendra
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mtd: spi-nor: Parse SFDP SCCR Map 



Parse just the 22nd dword and look for the 'DTR Octal Mode Enable
Volatile bit'.

SPI_NOR_IO_MODE_EN_VOLATILE should be set just for the flashes
that don't define the optional SFDP SCCR Map. For the others,
let the SFDP do its job and fill the SNOR_F_IO_MODE_EN_VOLATILE
flag. We avoid this way polluting the flash flags when declaring
one.

Signed-off-by: default avatarTudor Ambarus <tudor.ambarus@microchip.com>
Signed-off-by: default avatarPratyush Yadav <p.yadav@ti.com>
Signed-off-by: default avatarVignesh Raghavendra <vigneshr@ti.com>
Link: https://lore.kernel.org/r/20201005153138.6437-10-p.yadav@ti.com
parent c6908077

drivers/mtd/spi-nor/sfdp.c

+48 −0
Original line number Diff line number Diff line
@@ -21,6 +21,10 @@ 
#define SFDP_SECTOR_MAP_ID	0xff81	/* Sector Map Table */

#define SFDP_4BAIT_ID		0xff84  /* 4-byte Address Instruction Table */

#define SFDP_PROFILE1_ID	0xff05	/* xSPI Profile 1.0 table. */

#define SFDP_SCCR_MAP_ID	0xff87	/*

					 * Status, Control and Configuration

					 * Register Map.

					 */



#define SFDP_SIGNATURE		0x50444653U
@@ -1195,6 +1199,46 @@ static int spi_nor_parse_profile1(struct spi_nor *nor, 
	return ret;

}



#define SCCR_DWORD22_OCTAL_DTR_EN_VOLATILE		BIT(31)



/**

 * spi_nor_parse_sccr() - Parse the Status, Control and Configuration Register

 *                        Map.

 * @nor:		pointer to a 'struct spi_nor'

 * @sccr_header:	pointer to the 'struct sfdp_parameter_header' describing

 *			the SCCR Map table length and version.

 * @params:		pointer to the 'struct spi_nor_flash_parameter' to be.

 *

 * Return: 0 on success, -errno otherwise.

 */

static int spi_nor_parse_sccr(struct spi_nor *nor,

			      const struct sfdp_parameter_header *sccr_header,

			      struct spi_nor_flash_parameter *params)

{

	u32 *dwords, addr;

	size_t len;

	int ret;



	len = sccr_header->length * sizeof(*dwords);

	dwords = kmalloc(len, GFP_KERNEL);

	if (!dwords)

		return -ENOMEM;



	addr = SFDP_PARAM_HEADER_PTP(sccr_header);

	ret = spi_nor_read_sfdp(nor, addr, len, dwords);

	if (ret)

		goto out;



	le32_to_cpu_array(dwords, sccr_header->length);



	if (FIELD_GET(SCCR_DWORD22_OCTAL_DTR_EN_VOLATILE, dwords[22]))

		nor->flags |= SNOR_F_IO_MODE_EN_VOLATILE;



out:

	kfree(dwords);

	return ret;

}



/**

 * spi_nor_parse_sfdp() - parse the Serial Flash Discoverable Parameters.

 * @nor:		pointer to a 'struct spi_nor'
@@ -1300,6 +1344,10 @@ int spi_nor_parse_sfdp(struct spi_nor *nor, 
			err = spi_nor_parse_profile1(nor, param_header, params);

			break;



		case SFDP_SCCR_MAP_ID:

			err = spi_nor_parse_sccr(nor, param_header, params);

			break;



		default:

			break;

		}