mtd: spi-nor: sfdp: get the 1-1-8 and 1-8-8 protocol from SFDP

BFPT 17th DWORD contains the information about 1-1-8 and 1-8-8.
Parse BFPT DWORD[17] instruction to determine whether flash
supports 1-1-8 and 1-8-8, and set its dummy cycles accordingly.

Validated only the 1-1-8 read using a macronix flash with
Xilinx board zynq-picozed.
Signed-off-by: JaimeLiao <jaimeliao@mxic.com.tw>
Reviewed-by: Michael Walle <mwalle@kernel.org>
Link: https://lore.kernel.org/r/20231219102103.92738-2-jaimeliao.tw@gmail.com
[ta: update commit message, get rid of extra dereference]
Signed-off-by: Tudor Ambarus <tudor.ambarus@linaro.org>

drivers/mtd/spi-nor/sfdp.c

@@ -446,6 +446,7 @@ static int spi_nor_parse_bfpt(struct spi_nor *nor,
 	u32 dword;
 	u16 half;
 	u8 erase_mask;
+	u8 wait_states, mode_clocks, opcode;
 
 	/* JESD216 Basic Flash Parameter Table length is at least 9 DWORDs. */
 	if (bfpt_header->length < BFPT_DWORD_MAX_JESD216)
@@ -631,6 +632,32 @@ static int spi_nor_parse_bfpt(struct spi_nor *nor,
 	if (bfpt_header->length == BFPT_DWORD_MAX_JESD216B)
 		return spi_nor_post_bfpt_fixups(nor, bfpt_header, &bfpt);
 
+	/* Parse 1-1-8 read instruction */
+	opcode = FIELD_GET(BFPT_DWORD17_RD_1_1_8_CMD, bfpt.dwords[SFDP_DWORD(17)]);
+	if (opcode) {
+		mode_clocks = FIELD_GET(BFPT_DWORD17_RD_1_1_8_MODE_CLOCKS,
+					bfpt.dwords[SFDP_DWORD(17)]);
+		wait_states = FIELD_GET(BFPT_DWORD17_RD_1_1_8_WAIT_STATES,
+					bfpt.dwords[SFDP_DWORD(17)]);
+		params->hwcaps.mask |= SNOR_HWCAPS_READ_1_1_8;
+		spi_nor_set_read_settings(&params->reads[SNOR_CMD_READ_1_1_8],
+					  mode_clocks, wait_states, opcode,
+					  SNOR_PROTO_1_1_8);
+	}
+
+	/* Parse 1-8-8 read instruction */
+	opcode = FIELD_GET(BFPT_DWORD17_RD_1_8_8_CMD, bfpt.dwords[SFDP_DWORD(17)]);
+	if (opcode) {
+		mode_clocks = FIELD_GET(BFPT_DWORD17_RD_1_8_8_MODE_CLOCKS,
+					bfpt.dwords[SFDP_DWORD(17)]);
+		wait_states = FIELD_GET(BFPT_DWORD17_RD_1_8_8_WAIT_STATES,
+					bfpt.dwords[SFDP_DWORD(17)]);
+		params->hwcaps.mask |= SNOR_HWCAPS_READ_1_8_8;
+		spi_nor_set_read_settings(&params->reads[SNOR_CMD_READ_1_8_8],
+					  mode_clocks, wait_states, opcode,
+					  SNOR_PROTO_1_8_8);
+	}
+
 	/* 8D-8D-8D command extension. */
 	switch (bfpt.dwords[SFDP_DWORD(18)] & BFPT_DWORD18_CMD_EXT_MASK) {
 	case BFPT_DWORD18_CMD_EXT_REP:
@@ -968,6 +995,8 @@ static int spi_nor_parse_4bait(struct spi_nor *nor,
 		{ SNOR_HWCAPS_READ_1_1_1_DTR,	BIT(13) },
 		{ SNOR_HWCAPS_READ_1_2_2_DTR,	BIT(14) },
 		{ SNOR_HWCAPS_READ_1_4_4_DTR,	BIT(15) },
+		{ SNOR_HWCAPS_READ_1_1_8,	BIT(20) },
+		{ SNOR_HWCAPS_READ_1_8_8,	BIT(21) },
 	};
 	static const struct sfdp_4bait programs[] = {
 		{ SNOR_HWCAPS_PP,		BIT(6) },

drivers/mtd/spi-nor/sfdp.h

@@ -118,6 +118,13 @@ struct sfdp_bfpt {
 	(BFPT_DWORD16_EN4B_EN4B | BFPT_DWORD16_EX4B_EX4B)
 #define BFPT_DWORD16_SWRST_EN_RST		BIT(12)
 
+#define BFPT_DWORD17_RD_1_1_8_CMD		GENMASK(31, 24)
+#define BFPT_DWORD17_RD_1_1_8_MODE_CLOCKS	GENMASK(23, 21)
+#define BFPT_DWORD17_RD_1_1_8_WAIT_STATES	GENMASK(20, 16)
+#define BFPT_DWORD17_RD_1_8_8_CMD		GENMASK(15, 8)
+#define BFPT_DWORD17_RD_1_8_8_MODE_CLOCKS	GENMASK(7, 5)
+#define BFPT_DWORD17_RD_1_8_8_WAIT_STATES	GENMASK(4, 0)
+
 #define BFPT_DWORD18_CMD_EXT_MASK		GENMASK(30, 29)
 #define BFPT_DWORD18_CMD_EXT_REP		(0x0UL << 29) /* Repeat */
 #define BFPT_DWORD18_CMD_EXT_INV		(0x1UL << 29) /* Invert */