[PATCH v3 5/5] mtd: spi-nor: sfdp: Get the 8D-8D-8D byte order from BFPT

[Jaime Liao]

From: JaimeLiao <jaimeliao at mxic.com.tw>

Parse BFPT in order to retrieve the byte order in 8D-8D-8D mode.

Signed-off-by: Tudor Ambarus <tudor.ambarus at linaro.org>
---
 drivers/mtd/spi-nor/sfdp.c | 4 ++++
 drivers/mtd/spi-nor/sfdp.h | 1 +
 2 files changed, 5 insertions(+)

diff --git a/drivers/mtd/spi-nor/sfdp.c b/drivers/mtd/spi-nor/sfdp.c
index b3b11dfed789..2241207556bf 100644
--- a/drivers/mtd/spi-nor/sfdp.c
+++ b/drivers/mtd/spi-nor/sfdp.c
@@ -650,6 +650,10 @@ static int spi_nor_parse_bfpt(struct spi_nor *nor,
 		return -EOPNOTSUPP;
 	}
 
+	/* Byte order in 8D-8D-8D mode */
+	if (bfpt.dwords[SFDP_DWORD(18)] & BFPT_DWORD18_BYTE_ORDER_SWAPPED)
+		nor->flags |= SNOR_F_DTR_SWAB16;
+
 	return spi_nor_post_bfpt_fixups(nor, bfpt_header, &bfpt);
 }
 
diff --git a/drivers/mtd/spi-nor/sfdp.h b/drivers/mtd/spi-nor/sfdp.h
index 6eb99e1cdd61..eba760941d43 100644
--- a/drivers/mtd/spi-nor/sfdp.h
+++ b/drivers/mtd/spi-nor/sfdp.h
@@ -123,6 +123,7 @@ struct sfdp_bfpt {
 #define BFPT_DWORD18_CMD_EXT_INV		(0x1UL << 29) /* Invert */
 #define BFPT_DWORD18_CMD_EXT_RES		(0x2UL << 29) /* Reserved */
 #define BFPT_DWORD18_CMD_EXT_16B		(0x3UL << 29) /* 16-bit opcode */
+#define BFPT_DWORD18_BYTE_ORDER_SWAPPED		BIT(31) /* Byte order of 16-bit words in 8D-8D-8D mode */
 
 struct sfdp_parameter_header {
 	u8		id_lsb;
-- 
2.25.1