[PATCH 8/9] mtd: spi-nor-core: Rework spi_nor_cypress_octal_dtr_enable()

[tkuw584924 at gmail.com]

From: Takahiro Kuwano <Takahiro.Kuwano at infineon.com>

Enabling Octal DTR mode in multi-die package parts requires reister setup
for each die. That can be done by simple for-loop. write_enable() takes
effect to all die at once so we can call it before the loop. Besides we
can replace spi_mem_exec_op() calls with spansion_read/write_any_reg().
And finally, we must mask CFR2V[7:4] when changing dummy cycles, as
CFR2V[7] indicates current addressing mode and that should be 1 (4-byte
address mode) for multi-die package parts.

Signed-off-by: Takahiro Kuwano <Takahiro.Kuwano at infineon.com>
---
 drivers/mtd/spi/spi-nor-core.c | 54 +++++++++++++++++-----------------
 include/linux/mtd/spi-nor.h    |  1 +
 2 files changed, 28 insertions(+), 27 deletions(-)

diff --git a/drivers/mtd/spi/spi-nor-core.c b/drivers/mtd/spi/spi-nor-core.c
index d9b6bdc23892..4b0485b54668 100644
--- a/drivers/mtd/spi/spi-nor-core.c
+++ b/drivers/mtd/spi/spi-nor-core.c
@@ -3418,48 +3418,48 @@ static struct spi_nor_fixups s25fl256l_fixups = {
  */
 static int spi_nor_cypress_octal_dtr_enable(struct spi_nor *nor)
 {
-	struct spi_mem_op op;
+	u32 addr;
 	u8 buf;
-	u8 addr_width = 3;
 	int ret;
 
-	/* Use 24 dummy cycles for memory array reads. */
 	ret = write_enable(nor);
 	if (ret)
 		return ret;
 
-	buf = SPINOR_REG_CYPRESS_CFR2_MEMLAT_11_24;
-	op = (struct spi_mem_op)SPI_MEM_OP(SPI_MEM_OP_CMD(SPINOR_OP_WR_ANY_REG, 1),
-			SPI_MEM_OP_ADDR(addr_width, SPINOR_REG_CYPRESS_CFR2V, 1),
-			SPI_MEM_OP_NO_DUMMY,
-			SPI_MEM_OP_DATA_OUT(1, &buf, 1));
-	ret = spi_mem_exec_op(nor->spi, &op);
-	if (ret) {
-		dev_warn(nor->dev,
-			 "failed to set default memory latency value: %d\n",
-			 ret);
-		return ret;
-	}
-	ret = spi_nor_wait_till_ready(nor);
-	if (ret)
-		return ret;
+	/* Use 24 dummy cycles for memory array reads. */
+	for (addr = 0; addr < nor->mtd.size; addr += SZ_128M) {
+		ret = spansion_read_any_reg(nor,
+					    addr + SPINOR_REG_CYPRESS_CFR2V, 0,
+					    &buf);
+		if (ret)
+			return ret;
 
+		buf &= ~SPINOR_REG_CYPRESS_CFR2_MEMLAT_MASK;
+		buf |= SPINOR_REG_CYPRESS_CFR2_MEMLAT_11_24;
+		ret = spansion_write_any_reg(nor,
+					     addr + SPINOR_REG_CYPRESS_CFR2V,
+					     buf);
+		if (ret) {
+			dev_warn(nor->dev, "failed to set default memory latency value: %d\n", ret);
+			return ret;
+		}
+	}
 	nor->read_dummy = 24;
 
-	/* Set the octal and DTR enable bits. */
 	ret = write_enable(nor);
 	if (ret)
 		return ret;
 
+	/* Set the octal and DTR enable bits. */
 	buf = SPINOR_REG_CYPRESS_CFR5_OCT_DTR_EN;
-	op = (struct spi_mem_op)SPI_MEM_OP(SPI_MEM_OP_CMD(SPINOR_OP_WR_ANY_REG, 1),
-			SPI_MEM_OP_ADDR(addr_width, SPINOR_REG_CYPRESS_CFR5V, 1),
-			SPI_MEM_OP_NO_DUMMY,
-			SPI_MEM_OP_DATA_OUT(1, &buf, 1));
-	ret = spi_mem_exec_op(nor->spi, &op);
-	if (ret) {
-		dev_warn(nor->dev, "Failed to enable octal DTR mode\n");
-		return ret;
+	for (addr = 0; addr < nor->mtd.size; addr += SZ_128M) {
+		ret = spansion_write_any_reg(nor,
+					     addr + SPINOR_REG_CYPRESS_CFR5V,
+					     buf);
+		if (ret) {
+			dev_warn(nor->dev, "Failed to enable octal DTR mode\n");
+			return ret;
+		}
 	}
 
 	return 0;
diff --git a/include/linux/mtd/spi-nor.h b/include/linux/mtd/spi-nor.h
index 8a94e1203724..d1dbf3eadbf7 100644
--- a/include/linux/mtd/spi-nor.h
+++ b/include/linux/mtd/spi-nor.h
@@ -185,6 +185,7 @@
 #define SPINOR_REG_CYPRESS_STR1V		0x00800000
 #define SPINOR_REG_CYPRESS_CFR1V		0x00800002
 #define SPINOR_REG_CYPRESS_CFR2V		0x00800003
+#define SPINOR_REG_CYPRESS_CFR2_MEMLAT_MASK	GENMASK(3, 0)
 #define SPINOR_REG_CYPRESS_CFR2_MEMLAT_11_24	0xb
 #define SPINOR_REG_CYPRESS_CFR3V		0x00800004
 #define SPINOR_REG_CYPRESS_CFR3_PGSZ		BIT(4) /* Page size. */
-- 
2.25.1