[PATCH 09/15] mtd: spi-nor: winbond: Prepare the introduction of W35TxxNW parts

[Miquel Raynal]

This is a new octal DTR family, they require:
- a callback for enter octal DTR modes,
- a callback to configure the number of dummy cycles (since the spi-nor
  core picks up a variant for which the number of duty cycles does not
  match the hardware default).

These chips have a flag regiter, but no SR2.

They also feature automatic error correction (SECDEC).

Signed-off-by: Miquel Raynal <miquel.raynal at bootlin.com>
---
 drivers/mtd/spi-nor/winbond.c | 96 +++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 96 insertions(+)

diff --git a/drivers/mtd/spi-nor/winbond.c b/drivers/mtd/spi-nor/winbond.c
index f2daab39ea57..d33e693ed711 100644
--- a/drivers/mtd/spi-nor/winbond.c
+++ b/drivers/mtd/spi-nor/winbond.c
@@ -11,6 +11,13 @@
 #define WINBOND_NOR_OP_RDEAR	0xc8	/* Read Extended Address Register */
 #define WINBOND_NOR_OP_WREAR	0xc5	/* Write Extended Address Register */
 #define WINBOND_NOR_OP_SELDIE	0xc2	/* Select active die */
+#define WINBOND_NOR_OP_WR_VCR	0x81	/* Write VCR registers */
+#define   WINBOND_NOR_VCR_IO_MODE_CFG_REG 0x00 /* IO mode configuration address (VCR) */
+#define     WINBOND_NOR_VCR_IO_MODE_SSDR 0xFF
+#define     WINBOND_NOR_VCR_IO_MODE_ODDR 0xE7
+#define   WINBOND_NOR_VCR_DUMMY_CFG_REG 0x01 /* Dummy cycle configuration address (VCR) */
+#define WINBOND_NOR_OP_RD_FR	0x70	/* Read Flag registers */
+#define WINBOND_NOR_OP_CL_FR	0x50	/* Clear Flag registers */
 
 #define WINBOND_NOR_WREAR_OP(buf)					\
 	SPI_MEM_OP(SPI_MEM_OP_CMD(WINBOND_NOR_OP_WREAR, 0),		\
@@ -24,6 +31,12 @@
 		   SPI_MEM_OP_NO_DUMMY,					\
 		   SPI_MEM_OP_DATA_OUT(1, buf, 0))
 
+#define WINBOND_NOR_WR_VCR_OP(addr, buf)				\
+	SPI_MEM_OP(SPI_MEM_OP_CMD(WINBOND_NOR_OP_WR_VCR, 0),		\
+		   SPI_MEM_OP_ADDR(3, addr, 0),				\
+		   SPI_MEM_OP_NO_DUMMY,					\
+		   SPI_MEM_OP_DATA_OUT(1, buf, 0))
+
 static bool is_w25qxxrv(const struct spi_nor *nor)
 {
 	struct sfdp_header *sfdp_h = spi_nor_sfdp_get_header(nor);
@@ -252,6 +265,87 @@ static const struct spi_nor_fixups winbond_nor_ecc_configuration_fixups = {
 	.post_sfdp = winbond_nor_ecc_configuration_post_sfdp_fixups,
 };
 
+static int winbond_w35txxnw_nor_write_vcr(struct spi_nor *nor, u8 addr, u8 val)
+{
+	u8 *buf = nor->bouncebuf;
+	struct spi_mem_op op;
+	int ret;
+
+	if (!nor->spimem)
+		return -EOPNOTSUPP;
+
+	ret = spi_nor_write_enable(nor);
+	if (ret)
+		return ret;
+
+	buf[0] = val;
+	buf[1] = val;
+	op = (struct spi_mem_op)WINBOND_NOR_WR_VCR_OP(addr, buf);
+	spi_nor_spimem_setup_op(nor, &op, nor->reg_proto);
+	if (nor->reg_proto == SNOR_PROTO_8_8_8_DTR) {
+		op.addr.nbytes = 4;
+		op.data.nbytes = 2;
+	}
+
+	return spi_mem_exec_op(nor->spimem, &op);
+}
+
+static int winbond_w35txxnw_nor_set_dummy(struct spi_nor *nor, u8 dummy_cycles)
+{
+	return winbond_w35txxnw_nor_write_vcr(nor, WINBOND_NOR_VCR_DUMMY_CFG_REG,
+					      dummy_cycles);
+}
+
+static int winbond_w35txxnw_nor_set_octal_dtr(struct spi_nor *nor, bool enable)
+{
+	enum spi_nor_protocol proto_aft;
+	u8 *buf = nor->bouncebuf;
+	u8 rdid_dummy_aft, val;
+	int ret;
+
+	if (enable) {
+		val = WINBOND_NOR_VCR_IO_MODE_ODDR;
+		proto_aft = SNOR_PROTO_8_8_8_DTR;
+		rdid_dummy_aft = 16;
+	} else {
+		val = WINBOND_NOR_VCR_IO_MODE_SSDR;
+		proto_aft = SNOR_PROTO_1_1_1;
+		rdid_dummy_aft = 0;
+	}
+
+	ret = winbond_w35txxnw_nor_write_vcr(nor, WINBOND_NOR_VCR_IO_MODE_CFG_REG, val);
+	if (ret)
+		return ret;
+
+	/* Read flash ID to make sure the switch was successful */
+	ret = spi_nor_read_id(nor, 0, rdid_dummy_aft, buf, proto_aft);
+	if (ret) {
+		dev_err(nor->dev, "Cannot read JEDEC ID after %s 8D-8D-8D mode (%d)\n",
+			enable ? "enabling" : "disabling", ret);
+		return ret;
+	}
+
+	if (memcmp(buf, nor->info->id->bytes, nor->info->id->len))
+		return -EINVAL;
+
+	return 0;
+}
+
+static int winbond_w35txxnw_nor_late_init(struct spi_nor *nor)
+{
+	nor->params->set_octal_dtr = winbond_w35txxnw_nor_set_octal_dtr;
+	nor->params->set_dummy = winbond_w35txxnw_nor_set_dummy;
+	nor->params->opcodes.read_sr2 = 0;
+	nor->params->opcodes.write_sr1_and_sr2 = 0;
+
+	return 0;
+}
+
+static const struct spi_nor_fixups winbond_w35txxnw_nor_fixups = {
+	.post_sfdp = winbond_nor_ecc_configuration_post_sfdp_fixups,
+	.late_init = winbond_w35txxnw_nor_late_init,
+};
+
 static const struct flash_info winbond_nor_parts[] = {
 	{
 		.id = SNOR_ID(0xef, 0x30, 0x10),
@@ -673,6 +767,8 @@ static const struct spi_nor_fixup winbond_fixups[] = {
 	  .fixups = &winbond_nor_multi_die_fixups },
 	{ .id = SNOR_ID(0xef, 0x40, 0x22), .match = winbond_jv_match,
 	  .fixups = &winbond_nor_multi_die_fixups },
+	{ .id = SNOR_ID(0xef, 0x5b), .fixup_flags = SPI_NOR_IO_MODE_EN_VOLATILE,
+	  .fixups = &winbond_w35txxnw_nor_fixups },
 	{ .id = SNOR_ID(0xef, 0x60), .match = winbond_pw_with_ecc_match,
 	  .fixups = &winbond_nor_ecc_configuration_fixups },
 	{ .id = SNOR_ID(0xef, 0x60), .match = winbond_pw_match,

-- 
2.55.0