mtd: spi-nor: sfdp: prepare BFPT parsing for JESD216 rev D

JESD216 rev D makes BFPT 20 DWORDs. Update the BFPT size define to
reflect that.

The check for rev A or later compared the BFPT header length with the
maximum BFPT length, BFPT_DWORD_MAX. Since BFPT_DWORD_MAX was 16, and so
was the BFPT length for both rev A and B, this check worked fine. But
now, since BFPT_DWORD_MAX is 20, it means this check will also stop BFPT
parsing for rev A or B, since their length is 16.

So, instead check for BFPT_DWORD_MAX_JESD216 to stop BFPT parsing for
the first JESD216 version, and check for BFPT_DWORD_MAX_JESD216B for the
next two versions.

Signed-off-by: Pratyush Yadav <[email protected]>
Signed-off-by: Tudor Ambarus <[email protected]>

Author: Pratyush Yadav

drivers/mtd/spi-nor/sfdp.c

@@ -549,7 +549,7 @@ static int spi_nor_parse_bfpt(struct spi_nor *nor,
 				  SNOR_ERASE_TYPE_MASK;
 
 	/* Stop here if not JESD216 rev A or later. */
-	if (bfpt_header->length < BFPT_DWORD_MAX)
+	if (bfpt_header->length == BFPT_DWORD_MAX_JESD216)
 		return spi_nor_post_bfpt_fixups(nor, bfpt_header, &bfpt,
 						params);
 
@@ -605,6 +605,11 @@ static int spi_nor_parse_bfpt(struct spi_nor *nor,
 		return -EINVAL;
 	}
 
+	/* Stop here if not JESD216 rev C or later. */
+	if (bfpt_header->length == BFPT_DWORD_MAX_JESD216B)
+		return spi_nor_post_bfpt_fixups(nor, bfpt_header, &bfpt,
+						params);
+
 	return spi_nor_post_bfpt_fixups(nor, bfpt_header, &bfpt, params);
 }
 

drivers/mtd/spi-nor/sfdp.h

@@ -10,18 +10,19 @@
 /* Basic Flash Parameter Table */
 
 /*
- * JESD216 rev B defines a Basic Flash Parameter Table of 16 DWORDs.
+ * JESD216 rev D defines a Basic Flash Parameter Table of 20 DWORDs.
  * They are indexed from 1 but C arrays are indexed from 0.
  */
 #define BFPT_DWORD(i)		((i) - 1)
-#define BFPT_DWORD_MAX		16
+#define BFPT_DWORD_MAX		20
 
 struct sfdp_bfpt {
 	u32	dwords[BFPT_DWORD_MAX];
 };
 
 /* The first version of JESD216 defined only 9 DWORDs. */
 #define BFPT_DWORD_MAX_JESD216			9
+#define BFPT_DWORD_MAX_JESD216B			16
 
 /* 1st DWORD. */
 #define BFPT_DWORD1_FAST_READ_1_1_2		BIT(16)