mtd: spi-nor: core: Introduce SPI_NOR_SOFT_RESET flash_info fixup_flag

The Soft Reset and Rescue Sequence Support is defined in BFPT_DWORD(16)
starting with JESD216A. The first version of SFDP, JESD216 (April 2011),
defines just the first 9 BFPT DWORDS, thus it does not contain information
about the Software Reset and Rescue Support. Since this support can not
be discovered by parsing the first SFDP version, introduce a flash_info
fixup_flag that will be used either by flashes that define
JESD216 (April 2011) or by flashes that do not define SFDP at all.
In case a flash defines BFPT_DWORD(16) but with wrong values, one should
instead use a post_bfpt() hook and set SNOR_F_SOFT_RESET.

Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com>
Reviewed-by: Pratyush Yadav <p.yadav@ti.com>
Link: https://lore.kernel.org/r/20220209133656.374903-7-tudor.ambarus@microchip.com

Author: ambarus

drivers/mtd/spi-nor/core.c

@@ -2891,6 +2891,9 @@ static void spi_nor_init_fixup_flags(struct spi_nor *nor)
 
 	if (fixup_flags & SPI_NOR_IO_MODE_EN_VOLATILE)
 		nor->flags |= SNOR_F_IO_MODE_EN_VOLATILE;
+
+	if (fixup_flags & SPI_NOR_SOFT_RESET)
+		nor->flags |= SNOR_F_SOFT_RESET;
 }
 
 /**

drivers/mtd/spi-nor/core.h

@@ -495,6 +495,8 @@ struct spi_nor_fixups {
  *                            memory size above 128Mib.
  *   SPI_NOR_IO_MODE_EN_VOLATILE: flash enables the best available I/O mode
  *                            via a volatile bit.
+ *   SPI_NOR_SOFT_RESET:      flash supports software reset enable, reset
+ *                            sequence.
  * @mfr_flags:      manufacturer private flags. Used in the manufacturer fixup
  *                  hooks to differentiate support between flashes of the same
  *                  manufacturer.
@@ -537,6 +539,7 @@ struct flash_info {
 	u8 fixup_flags;
 #define SPI_NOR_4B_OPCODES		BIT(0)
 #define SPI_NOR_IO_MODE_EN_VOLATILE	BIT(1)
+#define SPI_NOR_SOFT_RESET		BIT(2)
 
 	u8 mfr_flags;