openwrtv4/target/linux/layerscape/patches-4.4/1099-mtd-spi-nor-fsl-quadspi-Add-fast-read-mode-support.patch

From c501cdf57682265b72a8180c06e4a01dc2978375 Mon Sep 17 00:00:00 2001
From: Yunhui Cui <B56489@freescale.com>
Date: Mon, 1 Feb 2016 18:26:23 +0800
Subject: [PATCH 099/113] mtd:spi-nor:fsl-quadspi:Add fast-read mode support

The qspi driver add generic fast-read mode for different
flash venders. There are some different board flash work on
different mode, such fast-read, quad-mode.
So we have to modify the third entrace parameter of spi_nor_scan().

Signed-off-by: Yunhui Cui <B56489@freescale.com>
---
 drivers/mtd/spi-nor/fsl-quadspi.c |   27 +++++++++++++++++++++------
 1 file changed, 21 insertions(+), 6 deletions(-)

--- a/drivers/mtd/spi-nor/fsl-quadspi.c
+++ b/drivers/mtd/spi-nor/fsl-quadspi.c
@@ -389,11 +389,21 @@ static void fsl_qspi_init_lut(struct fsl
 	/* Read */
 	lut_base = SEQID_READ * 4;
 
-	qspi_writel(q, LUT0(CMD, PAD1, read_op) | LUT1(ADDR, PAD1, addrlen),
-			base + QUADSPI_LUT(lut_base));
-	qspi_writel(q, LUT0(DUMMY, PAD1, read_dm) |
-		    LUT1(FSL_READ, PAD4, rxfifo),
-			base + QUADSPI_LUT(lut_base + 1));
+	if (nor->flash_read == SPI_NOR_FAST) {
+		qspi_writel(q, LUT0(CMD, PAD1, read_op) |
+			    LUT1(ADDR, PAD1, addrlen),
+				base + QUADSPI_LUT(lut_base));
+		qspi_writel(q,  LUT0(DUMMY, PAD1, read_dm) |
+			    LUT1(FSL_READ, PAD1, rxfifo),
+				base + QUADSPI_LUT(lut_base + 1));
+	} else if (nor->flash_read == SPI_NOR_QUAD) {
+		qspi_writel(q, LUT0(CMD, PAD1, read_op) |
+			    LUT1(ADDR, PAD1, addrlen),
+				base + QUADSPI_LUT(lut_base));
+		qspi_writel(q, LUT0(DUMMY, PAD1, read_dm) |
+			    LUT1(FSL_READ, PAD4, rxfifo),
+				base + QUADSPI_LUT(lut_base + 1));
+	}
 
 	/* Write enable */
 	lut_base = SEQID_WREN * 4;
@@ -468,6 +478,7 @@ static int fsl_qspi_get_seqid(struct fsl
 {
 	switch (cmd) {
 	case SPINOR_OP_READ_1_1_4:
+	case SPINOR_OP_READ_FAST:
 		return SEQID_READ;
 	case SPINOR_OP_WREN:
 		return SEQID_WREN;
@@ -964,6 +975,7 @@ static int fsl_qspi_probe(struct platfor
 	struct spi_nor *nor;
 	struct mtd_info *mtd;
 	int ret, i = 0;
+	enum read_mode mode = SPI_NOR_QUAD;
 
 	q = devm_kzalloc(dev, sizeof(*q), GFP_KERNEL);
 	if (!q)
@@ -1065,7 +1077,10 @@ static int fsl_qspi_probe(struct platfor
 		/* set the chip address for READID */
 		fsl_qspi_set_base_addr(q, nor);
 
-		ret = spi_nor_scan(nor, NULL, SPI_NOR_QUAD);
+		ret = of_property_read_bool(np, "m25p,fast-read");
+		mode = (ret) ? SPI_NOR_FAST : SPI_NOR_QUAD;
+
+		ret = spi_nor_scan(nor, NULL, mode);
 		if (ret)
 			goto mutex_failed;