[PATCH v2 0/4] rewrite mtk-quadspi spi-nor driver with spi-mem

[PATCH v2 0/4] rewrite mtk-quadspi spi-nor driver with spi-mem

[Chuanhong Guo]

This patchset adds a spi-mem driver for Mediatek SPI-NOR controller,
which already has limited support by mtk-quadspi. This new driver can
make use of full quadspi capability of this controller.

1st new commit makes spi-max-frequency optional to match current
binding doc and make this new driver compatible with old driver dt
bindings.

Changes since v1:
 two new commits.

Chuanhong Guo (4):
  spi: make spi-max-frequency optional
  spi: add support for mediatek spi-nor controller
  dt-bindings: convert mtk-quadspi binding doc for spi-mtk-nor
  mtd: spi-nor: remove mtk-quadspi driver

 .../mtk-quadspi.txt => spi/spi-mtk-nor.txt}   |  34 +-
 drivers/mtd/spi-nor/Kconfig                   |   8 -
 drivers/mtd/spi-nor/Makefile                  |   1 -
 drivers/mtd/spi-nor/mtk-quadspi.c             | 565 --------------
 drivers/spi/Kconfig                           |  10 +
 drivers/spi/Makefile                          |   1 +
 drivers/spi/spi-mtk-nor.c                     | 689 ++++++++++++++++++
 drivers/spi/spi.c                             |   9 +-
 8 files changed, 717 insertions(+), 600 deletions(-)
 rename Documentation/devicetree/bindings/{mtd/mtk-quadspi.txt => spi/spi-mtk-nor.txt} (62%)
 delete mode 100644 drivers/mtd/spi-nor/mtk-quadspi.c
 create mode 100644 drivers/spi/spi-mtk-nor.c

-- 
2.24.1

[PATCH v2 1/4] spi: make spi-max-frequency optional

[Chuanhong Guo]

We only need a spi-max-frequency when we specifically request a
spi frequency lower than the max speed of spi host.
This property is already documented as optional property and current
host drivers are implemented to operate at highest speed possible
when spi->max_speed_hz is 0.
This patch makes spi-max-frequency an optional property so that
we could just omit it to use max controller speed.

Signed-off-by: Chuanhong Guo <gch981213-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
---
Change since v1:
 new commit

 drivers/spi/spi.c | 9 ++-------
 1 file changed, 2 insertions(+), 7 deletions(-)

diff --git a/drivers/spi/spi.c b/drivers/spi/spi.c
index 38b4c78df506..c0c55dc79972 100644
--- a/drivers/spi/spi.c
+++ b/drivers/spi/spi.c
@@ -1955,13 +1955,8 @@ static int of_spi_parse_dt(struct spi_controller *ctlr, struct spi_device *spi,
 		spi->mode |= SPI_CS_HIGH;
 
 	/* Device speed */
-	rc = of_property_read_u32(nc, "spi-max-frequency", &value);
-	if (rc) {
-		dev_err(&ctlr->dev,
-			"%pOF has no valid 'spi-max-frequency' property (%d)\n", nc, rc);
-		return rc;
-	}
-	spi->max_speed_hz = value;
+	if (!of_property_read_u32(nc, "spi-max-frequency", &value))
+		spi->max_speed_hz = value;
 
 	return 0;
 }
-- 
2.24.1

[PATCH v2 2/4] spi: add support for mediatek spi-nor controller

[Chuanhong Guo]

This is a driver for mtk spi-nor controller using spi-mem interface.
The same controller already has limited support provided by mtk-quadspi
driver under spi-nor framework and this new driver is a replacement
for the old one.

Comparing to the old driver, this driver has following advantages:
1. It can handle any full-duplex spi transfer up to 6 bytes, and
   this is implemented using generic spi interface.
2. It take account into command opcode properly. The reading routine
   in this controller can only use 0x03 or 0x0b as opcode on 1-1-1
   transfers, but old driver doesn't implement this properly. This
   driver checks supported opcode explicitly and use (1) to perform
   unmatched operations.
3. It properly handles SFDP reading. Old driver can't read SFDP
   due to the bug mentioned in (2).
4. It can do 1-2-2 and 1-4-4 fast reading on spi-nor. These two ops
   requires parsing SFDP, which isn't possible in old driver. And
   the old driver is only flagged to support 1-1-2 mode.
5. It takes advantage of the DMA feature in this controller for
   long reads and supports IRQ on DMA requests to free cpu cycles
   from polling status registers on long DMA reading. It achieves
   up to 17.5MB/s reading speed (1-4-4 mode) which is way faster
   than the old one. IRQ is implemented as optional to maintain
   backward compatibility.

Signed-off-by: Chuanhong Guo <gch981213-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
---
Change since v1:
 none

 drivers/spi/Kconfig       |  10 +
 drivers/spi/Makefile      |   1 +
 drivers/spi/spi-mtk-nor.c | 689 ++++++++++++++++++++++++++++++++++++++
 3 files changed, 700 insertions(+)
 create mode 100644 drivers/spi/spi-mtk-nor.c

diff --git a/drivers/spi/Kconfig b/drivers/spi/Kconfig
index 82177db238be..57735ca844d9 100644
--- a/drivers/spi/Kconfig
+++ b/drivers/spi/Kconfig
@@ -450,6 +450,16 @@ config SPI_MT7621
 	help
 	  This selects a driver for the MediaTek MT7621 SPI Controller.
 
+config SPI_MTK_NOR
+	tristate "MediaTek SPI NOR controller"
+	depends on ARCH_MEDIATEK || COMPILE_TEST
+	help
+	  This enables support for SPI NOR controller found on MediaTek
+	  ARM SoCs. This is a controller specifically for SPI-NOR flash.
+	  It can perform generic SPI transfers up to 6 bytes via generic
+	  SPI interface as well as several SPI-NOR specific instructions
+	  via SPI MEM interface.
+
 config SPI_NPCM_FIU
 	tristate "Nuvoton NPCM FLASH Interface Unit"
 	depends on ARCH_NPCM || COMPILE_TEST
diff --git a/drivers/spi/Makefile b/drivers/spi/Makefile
index 74db1f2c3299..7eb3475a4520 100644
--- a/drivers/spi/Makefile
+++ b/drivers/spi/Makefile
@@ -64,6 +64,7 @@ obj-$(CONFIG_SPI_MPC52xx_PSC)		+= spi-mpc52xx-psc.o
 obj-$(CONFIG_SPI_MPC52xx)		+= spi-mpc52xx.o
 obj-$(CONFIG_SPI_MT65XX)                += spi-mt65xx.o
 obj-$(CONFIG_SPI_MT7621)		+= spi-mt7621.o
+obj-$(CONFIG_SPI_MTK_NOR)		+= spi-mtk-nor.o
 obj-$(CONFIG_SPI_MXIC)			+= spi-mxic.o
 obj-$(CONFIG_SPI_MXS)			+= spi-mxs.o
 obj-$(CONFIG_SPI_NPCM_FIU)		+= spi-npcm-fiu.o
diff --git a/drivers/spi/spi-mtk-nor.c b/drivers/spi/spi-mtk-nor.c
new file mode 100644
index 000000000000..c15a9910549f
--- /dev/null
+++ b/drivers/spi/spi-mtk-nor.c
@@ -0,0 +1,689 @@
+// SPDX-License-Identifier: GPL-2.0
+//
+// Mediatek SPI NOR controller driver
+//
+// Copyright (C) 2020 Chuanhong Guo <gch981213-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
+
+#include <linux/bits.h>
+#include <linux/clk.h>
+#include <linux/completion.h>
+#include <linux/dma-mapping.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/iopoll.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/of_device.h>
+#include <linux/spi/spi.h>
+#include <linux/spi/spi-mem.h>
+#include <linux/string.h>
+
+#define DRIVER_NAME "mtk-spi-nor"
+
+#define MTK_NOR_REG_CMD			0x00
+#define MTK_NOR_CMD_WRITE		BIT(4)
+#define MTK_NOR_CMD_PROGRAM		BIT(2)
+#define MTK_NOR_CMD_READ		BIT(0)
+#define MTK_NOR_CMD_MASK		GENMASK(5, 0)
+
+#define MTK_NOR_REG_PRG_CNT		0x04
+#define MTK_NOR_REG_RDATA		0x0c
+
+#define MTK_NOR_REG_RADR0		0x10
+#define MTK_NOR_REG_RADR(n)		(MTK_NOR_REG_RADR0 + 4 * (n))
+#define MTK_NOR_REG_RADR3		0xc8
+
+#define MTK_NOR_REG_WDATA		0x1c
+
+#define MTK_NOR_REG_PRGDATA0		0x20
+#define MTK_NOR_REG_PRGDATA(n)		(MTK_NOR_REG_PRGDATA0 + 4 * (n))
+#define MTK_NOR_REG_PRGDATA_MAX		5
+
+#define MTK_NOR_REG_SHIFT0		0x38
+#define MTK_NOR_REG_SHIFT(n)		(MTK_NOR_REG_SHIFT0 + 4 * (n))
+#define MTK_NOR_REG_SHIFT_MAX		9
+
+#define MTK_NOR_REG_CFG1		0x60
+#define MTK_NOR_FAST_READ		BIT(0)
+
+#define MTK_NOR_REG_CFG2		0x64
+#define MTK_NOR_WR_CUSTOM_OP_EN		BIT(4)
+#define MTK_NOR_WR_BUF_EN		BIT(0)
+
+#define MTK_NOR_REG_PP_DATA		0x98
+
+#define MTK_NOR_REG_IRQ_STAT		0xa8
+#define MTK_NOR_REG_IRQ_EN		0xac
+#define MTK_NOR_IRQ_DMA			BIT(7)
+#define MTK_NOR_IRQ_MASK		GENMASK(7, 0)
+
+#define MTK_NOR_REG_CFG3		0xb4
+#define MTK_NOR_DISABLE_WREN		BIT(7)
+#define MTK_NOR_DISABLE_SR_POLL		BIT(5)
+
+#define MTK_NOR_REG_WP			0xc4
+#define MTK_NOR_ENABLE_SF_CMD		0x30
+
+#define MTK_NOR_REG_BUSCFG		0xcc
+#define MTK_NOR_4B_ADDR			BIT(4)
+#define MTK_NOR_QUAD_ADDR		BIT(3)
+#define MTK_NOR_QUAD_READ		BIT(2)
+#define MTK_NOR_DUAL_ADDR		BIT(1)
+#define MTK_NOR_DUAL_READ		BIT(0)
+#define MTK_NOR_BUS_MODE_MASK		GENMASK(4, 0)
+
+#define MTK_NOR_REG_DMA_CTL		0x718
+#define MTK_NOR_DMA_START		BIT(0)
+
+#define MTK_NOR_REG_DMA_FADR		0x71c
+#define MTK_NOR_REG_DMA_DADR		0x720
+#define MTK_NOR_REG_DMA_END_DADR	0x724
+
+#define MTK_NOR_PRG_MAX_SIZE		6
+// Reading DMA src/dst addresses have to be 16-byte aligned
+#define MTK_NOR_DMA_ALIGN		16
+#define MTK_NOR_DMA_ALIGN_MASK		(MTK_NOR_DMA_ALIGN - 1)
+// and we allocate a bounce buffer if destination address isn't aligned.
+#define MTK_NOR_BOUNCE_BUF_SIZE		PAGE_SIZE
+
+// Buffered page program can do one 128-byte transfer
+#define MTK_NOR_PP_SIZE			128
+
+#define CLK_TO_US(sp, clkcnt)		((clkcnt) * 1000000 / sp->spi_freq)
+
+struct mtk_nor {
+	struct spi_controller *ctlr;
+	struct device *dev;
+	void __iomem *base;
+	u8 *buffer;
+	struct clk *spi_clk;
+	struct clk *ctlr_clk;
+	unsigned int spi_freq;
+	bool wbuf_en;
+	bool has_irq;
+	struct completion op_done;
+};
+
+static inline void mtk_nor_rmw(struct mtk_nor *sp, u32 reg, u32 set, u32 clr)
+{
+	u32 val = readl(sp->base + reg);
+
+	val &= ~clr;
+	val |= set;
+	writel(val, sp->base + reg);
+}
+
+static inline int mtk_nor_cmd_exec(struct mtk_nor *sp, u32 cmd, ulong clk)
+{
+	ulong delay = CLK_TO_US(sp, clk);
+	u32 reg;
+	int ret;
+
+	writel(cmd, sp->base + MTK_NOR_REG_CMD);
+	ret = readl_poll_timeout(sp->base + MTK_NOR_REG_CMD, reg, !(reg & cmd),
+				 delay / 3, (delay + 1) * 200);
+	if (ret < 0)
+		dev_err(sp->dev, "command %u timeout.\n", cmd);
+	return ret;
+}
+
+static void mtk_nor_set_addr(struct mtk_nor *sp, const struct spi_mem_op *op)
+{
+	u32 addr = op->addr.val;
+	int i;
+
+	for (i = 0; i < 3; i++) {
+		writeb(addr & 0xff, sp->base + MTK_NOR_REG_RADR(i));
+		addr >>= 8;
+	}
+	if (op->addr.nbytes == 4) {
+		writeb(addr & 0xff, sp->base + MTK_NOR_REG_RADR3);
+		mtk_nor_rmw(sp, MTK_NOR_REG_BUSCFG, MTK_NOR_4B_ADDR, 0);
+	} else {
+		mtk_nor_rmw(sp, MTK_NOR_REG_BUSCFG, 0, MTK_NOR_4B_ADDR);
+	}
+}
+
+static bool mtk_nor_match_read(const struct spi_mem_op *op)
+{
+	int dummy = 0;
+
+	if (op->dummy.buswidth)
+		dummy = op->dummy.nbytes * BITS_PER_BYTE / op->dummy.buswidth;
+
+	if ((op->data.buswidth == 2) || (op->data.buswidth == 4)) {
+		if (op->addr.buswidth == 1)
+			return dummy == 8;
+		else if (op->addr.buswidth == 2)
+			return dummy == 4;
+		else if (op->addr.buswidth == 4)
+			return dummy == 6;
+	} else if ((op->addr.buswidth == 1) && (op->data.buswidth == 1)) {
+		if (op->cmd.opcode == 0x03)
+			return dummy == 0;
+		else if (op->cmd.opcode == 0x0b)
+			return dummy == 8;
+	}
+	return false;
+}
+
+static int mtk_nor_adjust_op_size(struct spi_mem *mem, struct spi_mem_op *op)
+{
+	size_t len;
+
+	if (!op->data.nbytes)
+		return 0;
+
+	if ((op->addr.nbytes == 3) || (op->addr.nbytes == 4)) {
+		if ((op->data.dir == SPI_MEM_DATA_IN) &&
+		    mtk_nor_match_read(op)) {
+			if ((op->addr.val & MTK_NOR_DMA_ALIGN_MASK) ||
+			    (op->data.nbytes < MTK_NOR_DMA_ALIGN))
+				op->data.nbytes = 1;
+			else if (!((ulong)(op->data.buf.in) &
+				   MTK_NOR_DMA_ALIGN_MASK))
+				op->data.nbytes &= ~MTK_NOR_DMA_ALIGN_MASK;
+			else if (op->data.nbytes > MTK_NOR_BOUNCE_BUF_SIZE)
+				op->data.nbytes = MTK_NOR_BOUNCE_BUF_SIZE;
+			return 0;
+		} else if (op->data.dir == SPI_MEM_DATA_OUT) {
+			if (op->data.nbytes >= MTK_NOR_PP_SIZE)
+				op->data.nbytes = MTK_NOR_PP_SIZE;
+			else
+				op->data.nbytes = 1;
+			return 0;
+		}
+	}
+
+	len = MTK_NOR_PRG_MAX_SIZE - sizeof(op->cmd.opcode) - op->addr.nbytes -
+	      op->dummy.nbytes;
+	if (op->data.nbytes > len)
+		op->data.nbytes = len;
+
+	return 0;
+}
+
+static bool mtk_nor_supports_op(struct spi_mem *mem,
+				const struct spi_mem_op *op)
+{
+	size_t len;
+
+	if (op->cmd.buswidth != 1)
+		return false;
+
+	if ((op->addr.nbytes == 3) || (op->addr.nbytes == 4)) {
+		if ((op->data.dir == SPI_MEM_DATA_IN) && mtk_nor_match_read(op))
+			return true;
+		else if (op->data.dir == SPI_MEM_DATA_OUT)
+			return (op->addr.buswidth == 1) &&
+			       (op->dummy.buswidth == 0) &&
+			       (op->data.buswidth == 1);
+	}
+	len = sizeof(op->cmd.opcode) + op->addr.nbytes + op->dummy.nbytes;
+	if ((len > MTK_NOR_PRG_MAX_SIZE) ||
+	    ((op->data.nbytes) && (len == MTK_NOR_PRG_MAX_SIZE)))
+		return false;
+	return true;
+}
+
+static void mtk_nor_setup_bus(struct mtk_nor *sp, const struct spi_mem_op *op)
+{
+	u32 reg = 0;
+
+	if (op->addr.nbytes == 4)
+		reg |= MTK_NOR_4B_ADDR;
+
+	if (op->data.buswidth == 4) {
+		reg |= MTK_NOR_QUAD_READ;
+		writeb(op->cmd.opcode, sp->base + MTK_NOR_REG_PRGDATA(4));
+		if (op->addr.buswidth == 4)
+			reg |= MTK_NOR_QUAD_ADDR;
+	} else if (op->data.buswidth == 2) {
+		reg |= MTK_NOR_DUAL_READ;
+		writeb(op->cmd.opcode, sp->base + MTK_NOR_REG_PRGDATA(3));
+		if (op->addr.buswidth == 2)
+			reg |= MTK_NOR_DUAL_ADDR;
+	} else {
+		if (op->cmd.opcode == 0x0b)
+			mtk_nor_rmw(sp, MTK_NOR_REG_CFG1, MTK_NOR_FAST_READ, 0);
+		else
+			mtk_nor_rmw(sp, MTK_NOR_REG_CFG1, 0, MTK_NOR_FAST_READ);
+	}
+	mtk_nor_rmw(sp, MTK_NOR_REG_BUSCFG, reg, MTK_NOR_BUS_MODE_MASK);
+}
+
+static int mtk_nor_read_dma(struct mtk_nor *sp, u32 from, unsigned int length,
+			    u8 *buffer)
+{
+	int ret = 0;
+	ulong delay;
+	u32 reg;
+	dma_addr_t dma_addr;
+
+	dma_addr = dma_map_single(sp->dev, buffer, length, DMA_FROM_DEVICE);
+	if (dma_mapping_error(sp->dev, dma_addr)) {
+		dev_err(sp->dev, "failed to map dma buffer.\n");
+		return -EINVAL;
+	}
+
+	writel(from, sp->base + MTK_NOR_REG_DMA_FADR);
+	writel(dma_addr, sp->base + MTK_NOR_REG_DMA_DADR);
+	writel(dma_addr + length, sp->base + MTK_NOR_REG_DMA_END_DADR);
+
+	if (sp->has_irq) {
+		reinit_completion(&sp->op_done);
+		mtk_nor_rmw(sp, MTK_NOR_REG_IRQ_EN, MTK_NOR_IRQ_DMA, 0);
+	}
+
+	mtk_nor_rmw(sp, MTK_NOR_REG_DMA_CTL, MTK_NOR_DMA_START, 0);
+
+	delay = CLK_TO_US(sp, (length + 5) * BITS_PER_BYTE);
+
+	if (sp->has_irq) {
+		if (!wait_for_completion_timeout(&sp->op_done,
+						 (delay + 1) * 100))
+			ret = -ETIMEDOUT;
+	} else {
+		ret = readl_poll_timeout(sp->base + MTK_NOR_REG_DMA_CTL, reg,
+					 !(reg & MTK_NOR_DMA_START), delay / 3,
+					 (delay + 1) * 100);
+	}
+
+	dma_unmap_single(sp->dev, dma_addr, length, DMA_FROM_DEVICE);
+	if (ret < 0)
+		dev_err(sp->dev, "dma read timeout.\n");
+
+	return ret;
+}
+
+static int mtk_nor_read_bounce(struct mtk_nor *sp, u32 from,
+			       unsigned int length, u8 *buffer)
+{
+	unsigned int rdlen;
+	int ret;
+
+	if (length & MTK_NOR_DMA_ALIGN_MASK)
+		rdlen = (length + MTK_NOR_DMA_ALIGN) & ~MTK_NOR_DMA_ALIGN_MASK;
+	else
+		rdlen = length;
+
+	ret = mtk_nor_read_dma(sp, from, rdlen, sp->buffer);
+	if (ret)
+		return ret;
+
+	memcpy(buffer, sp->buffer, length);
+	return 0;
+}
+
+static int mtk_nor_read_pio(struct mtk_nor *sp, const struct spi_mem_op *op)
+{
+	u8 *buf = op->data.buf.in;
+	int ret;
+
+	ret = mtk_nor_cmd_exec(sp, MTK_NOR_CMD_READ, 6 * BITS_PER_BYTE);
+	if (!ret)
+		buf[0] = readb(sp->base + MTK_NOR_REG_RDATA);
+	return ret;
+}
+
+static int mtk_nor_write_buffer_enable(struct mtk_nor *sp)
+{
+	int ret;
+	u32 val;
+
+	if (sp->wbuf_en)
+		return 0;
+
+	val = readl(sp->base + MTK_NOR_REG_CFG2);
+	writel(val | MTK_NOR_WR_BUF_EN, sp->base + MTK_NOR_REG_CFG2);
+	ret = readl_poll_timeout(sp->base + MTK_NOR_REG_CFG2, val,
+				 val & MTK_NOR_WR_BUF_EN, 0, 10000);
+	if (!ret)
+		sp->wbuf_en = true;
+	return ret;
+}
+
+static int mtk_nor_write_buffer_disable(struct mtk_nor *sp)
+{
+	int ret;
+	u32 val;
+
+	if (!sp->wbuf_en)
+		return 0;
+	val = readl(sp->base + MTK_NOR_REG_CFG2);
+	writel(val & ~MTK_NOR_WR_BUF_EN, sp->base + MTK_NOR_REG_CFG2);
+	ret = readl_poll_timeout(sp->base + MTK_NOR_REG_CFG2, val,
+				 !(val & MTK_NOR_WR_BUF_EN), 0, 10000);
+	if (!ret)
+		sp->wbuf_en = false;
+	return ret;
+}
+
+static int mtk_nor_pp_buffered(struct mtk_nor *sp, const struct spi_mem_op *op)
+{
+	const u8 *buf = op->data.buf.out;
+	u32 val;
+	int ret, i;
+
+	ret = mtk_nor_write_buffer_enable(sp);
+	if (ret < 0)
+		return ret;
+
+	for (i = 0; i < op->data.nbytes; i += 4) {
+		val = buf[i + 3] << 24 | buf[i + 2] << 16 | buf[i + 1] << 8 |
+		      buf[i];
+		writel(val, sp->base + MTK_NOR_REG_PP_DATA);
+	}
+	return mtk_nor_cmd_exec(sp, MTK_NOR_CMD_WRITE,
+				(op->data.nbytes + 5) * BITS_PER_BYTE);
+}
+
+static int mtk_nor_pp_unbuffered(struct mtk_nor *sp,
+				 const struct spi_mem_op *op)
+{
+	const u8 *buf = op->data.buf.out;
+	int ret;
+
+	ret = mtk_nor_write_buffer_disable(sp);
+	if (ret < 0)
+		return ret;
+	writeb(buf[0], sp->base + MTK_NOR_REG_WDATA);
+	return mtk_nor_cmd_exec(sp, MTK_NOR_CMD_WRITE, 6 * BITS_PER_BYTE);
+}
+
+int mtk_nor_exec_op(struct spi_mem *mem, const struct spi_mem_op *op)
+{
+	struct mtk_nor *sp = spi_controller_get_devdata(mem->spi->master);
+	int ret;
+
+	if ((op->data.nbytes == 0) ||
+	    ((op->addr.nbytes != 3) && (op->addr.nbytes != 4)))
+		return -ENOTSUPP;
+
+	if (op->data.dir == SPI_MEM_DATA_OUT) {
+		mtk_nor_set_addr(sp, op);
+		writeb(op->cmd.opcode, sp->base + MTK_NOR_REG_PRGDATA0);
+		if (op->data.nbytes == MTK_NOR_PP_SIZE)
+			return mtk_nor_pp_buffered(sp, op);
+		return mtk_nor_pp_unbuffered(sp, op);
+	}
+
+	if ((op->data.dir == SPI_MEM_DATA_IN) && mtk_nor_match_read(op)) {
+		ret = mtk_nor_write_buffer_disable(sp);
+		if (ret < 0)
+			return ret;
+		mtk_nor_setup_bus(sp, op);
+		if (op->data.nbytes == 1) {
+			mtk_nor_set_addr(sp, op);
+			return mtk_nor_read_pio(sp, op);
+		} else if (((ulong)(op->data.buf.in) &
+			    MTK_NOR_DMA_ALIGN_MASK)) {
+			return mtk_nor_read_bounce(sp, op->addr.val,
+						   op->data.nbytes,
+						   op->data.buf.in);
+		} else {
+			return mtk_nor_read_dma(sp, op->addr.val,
+						op->data.nbytes,
+						op->data.buf.in);
+		}
+	}
+
+	return -ENOTSUPP;
+}
+
+static int mtk_nor_setup(struct spi_device *spi)
+{
+	struct mtk_nor *sp = spi_controller_get_devdata(spi->master);
+
+	if (spi->max_speed_hz && (spi->max_speed_hz < sp->spi_freq)) {
+		dev_err(&spi->dev, "spi clock should be %u Hz.\n",
+			sp->spi_freq);
+		return -EINVAL;
+	}
+	spi->max_speed_hz = sp->spi_freq;
+
+	return 0;
+}
+
+static int mtk_nor_transfer_one_message(struct spi_controller *master,
+					struct spi_message *m)
+{
+	struct mtk_nor *sp = spi_controller_get_devdata(master);
+	struct spi_transfer *t = NULL;
+	unsigned long trx_len = 0;
+	int stat = 0;
+	int reg_offset = MTK_NOR_REG_PRGDATA_MAX;
+	void __iomem *reg;
+	const u8 *txbuf;
+	u8 *rxbuf;
+	int i;
+
+	list_for_each_entry(t, &m->transfers, transfer_list) {
+		txbuf = t->tx_buf;
+		for (i = 0; i < t->len; i++, reg_offset--) {
+			reg = sp->base + MTK_NOR_REG_PRGDATA(reg_offset);
+			if (txbuf)
+				writeb(txbuf[i], reg);
+			else
+				writeb(0, reg);
+		}
+		trx_len += t->len;
+	}
+
+	writel(trx_len * BITS_PER_BYTE, sp->base + MTK_NOR_REG_PRG_CNT);
+
+	stat = mtk_nor_cmd_exec(sp, MTK_NOR_CMD_PROGRAM,
+				trx_len * BITS_PER_BYTE);
+	if (stat < 0)
+		goto msg_done;
+
+	reg_offset = trx_len - 1;
+	list_for_each_entry(t, &m->transfers, transfer_list) {
+		rxbuf = t->rx_buf;
+		for (i = 0; i < t->len; i++, reg_offset--) {
+			reg = sp->base + MTK_NOR_REG_SHIFT(reg_offset);
+			if (rxbuf)
+				rxbuf[i] = readb(reg);
+		}
+	}
+
+	m->actual_length = trx_len;
+msg_done:
+	m->status = stat;
+	spi_finalize_current_message(master);
+
+	return 0;
+}
+
+static void mtk_nor_disable_clk(struct mtk_nor *sp)
+{
+	clk_disable_unprepare(sp->spi_clk);
+	clk_disable_unprepare(sp->ctlr_clk);
+}
+
+static int mtk_nor_enable_clk(struct mtk_nor *sp)
+{
+	int ret;
+
+	ret = clk_prepare_enable(sp->spi_clk);
+	if (ret)
+		return ret;
+
+	ret = clk_prepare_enable(sp->ctlr_clk);
+	if (ret) {
+		clk_disable_unprepare(sp->spi_clk);
+		return ret;
+	}
+
+	return 0;
+}
+
+static int mtk_nor_init(struct mtk_nor *sp)
+{
+	int ret;
+
+	ret = mtk_nor_enable_clk(sp);
+	if (ret)
+		return ret;
+
+	sp->spi_freq = clk_get_rate(sp->spi_clk);
+
+	writel(MTK_NOR_ENABLE_SF_CMD, sp->base + MTK_NOR_REG_WP);
+	mtk_nor_rmw(sp, MTK_NOR_REG_CFG2, MTK_NOR_WR_CUSTOM_OP_EN, 0);
+	mtk_nor_rmw(sp, MTK_NOR_REG_CFG3,
+		    MTK_NOR_DISABLE_WREN | MTK_NOR_DISABLE_SR_POLL, 0);
+
+	return ret;
+}
+
+static irqreturn_t mtk_nor_irq_handler(int irq, void *data)
+{
+	struct mtk_nor *sp = data;
+	u32 irq_status, irq_enabled;
+
+	irq_status = readl(sp->base + MTK_NOR_REG_IRQ_STAT);
+	irq_enabled = readl(sp->base + MTK_NOR_REG_IRQ_EN);
+	// write status back to clear interrupt
+	writel(irq_status, sp->base + MTK_NOR_REG_IRQ_STAT);
+
+	if (!(irq_status & irq_enabled))
+		return IRQ_NONE;
+
+	if (irq_status & MTK_NOR_IRQ_DMA) {
+		complete(&sp->op_done);
+		writel(0, sp->base + MTK_NOR_REG_IRQ_EN);
+	}
+
+	return IRQ_HANDLED;
+}
+
+static size_t mtk_max_msg_size(struct spi_device *spi)
+{
+	return MTK_NOR_PRG_MAX_SIZE;
+}
+
+static const struct spi_controller_mem_ops mtk_nor_mem_ops = {
+	.adjust_op_size = mtk_nor_adjust_op_size,
+	.supports_op = mtk_nor_supports_op,
+	.exec_op = mtk_nor_exec_op
+};
+
+static const struct of_device_id mtk_nor_match[] = {
+	{ .compatible = "mediatek,mt8173-nor" },
+	{ /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(of, mtk_nor_match);
+
+static int mtk_nor_probe(struct platform_device *pdev)
+{
+	struct spi_controller *ctlr;
+	struct mtk_nor *sp;
+	void __iomem *base;
+	u8 *buffer;
+	struct clk *spi_clk, *ctlr_clk;
+	int ret, irq;
+
+	base = devm_platform_ioremap_resource(pdev, 0);
+	if (IS_ERR(base))
+		return PTR_ERR(base);
+
+	spi_clk = devm_clk_get(&pdev->dev, "spi");
+	if (IS_ERR(spi_clk))
+		return PTR_ERR(spi_clk);
+
+	ctlr_clk = devm_clk_get(&pdev->dev, "sf");
+	if (IS_ERR(ctlr_clk))
+		return PTR_ERR(ctlr_clk);
+
+	buffer = devm_kmalloc(&pdev->dev,
+			      MTK_NOR_BOUNCE_BUF_SIZE + MTK_NOR_DMA_ALIGN,
+			      GFP_KERNEL);
+	if (!buffer)
+		return -ENOMEM;
+
+	if ((ulong)buffer & MTK_NOR_DMA_ALIGN_MASK)
+		buffer = (u8 *)(((ulong)buffer + MTK_NOR_DMA_ALIGN) &
+				~MTK_NOR_DMA_ALIGN_MASK);
+
+	ctlr = spi_alloc_master(&pdev->dev, sizeof(*sp));
+	if (!ctlr) {
+		dev_err(&pdev->dev, "failed to allocate spi controller\n");
+		return -ENOMEM;
+	}
+
+	ctlr->bits_per_word_mask = SPI_BPW_MASK(8);
+	ctlr->dev.of_node = pdev->dev.of_node;
+	ctlr->max_message_size = mtk_max_msg_size;
+	ctlr->mem_ops = &mtk_nor_mem_ops;
+	ctlr->mode_bits = SPI_RX_DUAL | SPI_RX_QUAD | SPI_TX_DUAL | SPI_TX_QUAD;
+	ctlr->num_chipselect = 1;
+	ctlr->setup = mtk_nor_setup;
+	ctlr->transfer_one_message = mtk_nor_transfer_one_message;
+
+	dev_set_drvdata(&pdev->dev, ctlr);
+
+	sp = spi_controller_get_devdata(ctlr);
+	sp->base = base;
+	sp->buffer = buffer;
+	sp->has_irq = false;
+	sp->wbuf_en = false;
+	sp->ctlr = ctlr;
+	sp->dev = &pdev->dev;
+	sp->spi_clk = spi_clk;
+	sp->ctlr_clk = ctlr_clk;
+
+	irq = platform_get_irq_optional(pdev, 0);
+	if (irq < 0) {
+		dev_warn(sp->dev, "IRQ not available.");
+	} else {
+		writel(MTK_NOR_IRQ_MASK, base + MTK_NOR_REG_IRQ_STAT);
+		writel(0, base + MTK_NOR_REG_IRQ_EN);
+		ret = devm_request_irq(sp->dev, irq, mtk_nor_irq_handler, 0,
+				       pdev->name, sp);
+		if (ret < 0) {
+			dev_warn(sp->dev, "failed to request IRQ.");
+		} else {
+			init_completion(&sp->op_done);
+			sp->has_irq = true;
+		}
+	}
+
+	ret = mtk_nor_init(sp);
+	if (ret < 0) {
+		kfree(ctlr);
+		return ret;
+	}
+
+	dev_info(&pdev->dev, "spi frequency: %d Hz\n", sp->spi_freq);
+
+	return devm_spi_register_controller(&pdev->dev, ctlr);
+}
+
+static int mtk_nor_remove(struct platform_device *pdev)
+{
+	struct spi_controller *ctlr;
+	struct mtk_nor *sp;
+
+	ctlr = dev_get_drvdata(&pdev->dev);
+	sp = spi_controller_get_devdata(ctlr);
+
+	mtk_nor_disable_clk(sp);
+
+	return 0;
+}
+
+static struct platform_driver mtk_nor_driver = {
+	.driver = {
+		.name = DRIVER_NAME,
+		.of_match_table = mtk_nor_match,
+	},
+	.probe = mtk_nor_probe,
+	.remove = mtk_nor_remove,
+};
+
+module_platform_driver(mtk_nor_driver);
+
+MODULE_DESCRIPTION("Mediatek SPI NOR controller driver");
+MODULE_AUTHOR("Chuanhong Guo <gch981213-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>");
+MODULE_LICENSE("GPL v2");
+MODULE_ALIAS("platform:" DRIVER_NAME);
-- 
2.24.1

[PATCH v2 3/4] dt-bindings: convert mtk-quadspi binding doc for spi-mtk-nor

[Chuanhong Guo]

spi-mtk-nor is a driver to replace mtk-quadspi and they have almost
the same device-tree bindings. Reuse this binding documentation and
convert it for new driver:

1. "Mediatek SoCs" -> "Mediatek ARM SoCs" because MTK MIPS SoCs
   use different controllers.
2. document "interrupts" as a required property because it's
   available on all SoCs with this controller and new driver takes
   advantages of it. It's implemented as optional only to maintain
   backward compatibility.
3. replace binding example with a mt7629 one because this is the
   only one I know the interrupt assignment.

Signed-off-by: Chuanhong Guo <gch981213-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
---
Change since v1:
 none

 .../mtk-quadspi.txt => spi/spi-mtk-nor.txt}   | 34 ++++++++-----------
 1 file changed, 15 insertions(+), 19 deletions(-)
 rename Documentation/devicetree/bindings/{mtd/mtk-quadspi.txt => spi/spi-mtk-nor.txt} (62%)

diff --git a/Documentation/devicetree/bindings/mtd/mtk-quadspi.txt b/Documentation/devicetree/bindings/spi/spi-mtk-nor.txt
similarity index 62%
rename from Documentation/devicetree/bindings/mtd/mtk-quadspi.txt
rename to Documentation/devicetree/bindings/spi/spi-mtk-nor.txt
index a12e3b5c495d..829da480b9a9 100644
--- a/Documentation/devicetree/bindings/mtd/mtk-quadspi.txt
+++ b/Documentation/devicetree/bindings/spi/spi-mtk-nor.txt
@@ -1,4 +1,4 @@
-* Serial NOR flash controller for MediaTek SoCs
+* SPI NOR flash controller for MediaTek ARM SoCs
 
 Required properties:
 - compatible: 	  For mt8173, compatible should be "mediatek,mt8173-nor",
@@ -13,6 +13,7 @@ Required properties:
 		  "mediatek,mt7629-nor", "mediatek,mt8173-nor"
 		  "mediatek,mt8173-nor"
 - reg: 		  physical base address and length of the controller's register
+- interrupts:	  Interrupt number used by the controller.
 - clocks: 	  the phandle of the clocks needed by the nor controller
 - clock-names: 	  the names of the clocks
 		  the clocks should be named "spi" and "sf". "spi" is used for spi bus,
@@ -22,29 +23,24 @@ Required properties:
 - #address-cells: should be <1>
 - #size-cells:	  should be <0>
 
-The SPI flash must be a child of the nor_flash node and must have a
-compatible property. Also see jedec,spi-nor.txt.
-
-Required properties:
-- compatible:	  May include a device-specific string consisting of the manufacturer
-		  and name of the chip. Must also include "jedec,spi-nor" for any
-		  SPI NOR flash that can be identified by the JEDEC READ ID opcode (0x9F).
-- reg :		  Chip-Select number
+There should be only one spi slave device following generic spi bindings.
+It's not recommended to use this controller for devices other than SPI NOR
+flash due to limited transfer capability of this controller.
 
 Example:
+#include <dt-bindings/interrupt-controller/irq.h>
+#include <dt-bindings/interrupt-controller/arm-gic.h>
+#include <dt-bindings/clock/mt7629-clk.h>
 
-nor_flash: spi@1100d000 {
-	compatible = "mediatek,mt8173-nor";
-	reg = <0 0x1100d000 0 0xe0>;
-	clocks = <&pericfg CLK_PERI_SPI>,
-		 <&topckgen CLK_TOP_SPINFI_IFR_SEL>;
+spi_nor: spi@11014000 {
+	compatible = "mediatek,mt7629-nor",
+		     "mediatek,mt8173-nor";
+	reg = <0x11014000 0xe0>;
+	interrupts = <GIC_SPI 88 IRQ_TYPE_LEVEL_LOW>;
+	clocks = <&pericfg CLK_PERI_FLASH_PD>,
+		 <&topckgen CLK_TOP_FLASH_SEL>;
 	clock-names = "spi", "sf";
 	#address-cells = <1>;
 	#size-cells = <0>;
-
-	flash@0 {
-		compatible = "jedec,spi-nor";
-		reg = <0>;
-	};
 };
 
-- 
2.24.1

Re: [PATCH v2 3/4] dt-bindings: convert mtk-quadspi binding doc for spi-mtk-nor

[Rob Herring]

On Fri, Feb 28, 2020 at 12:36:35PM +0800, Chuanhong Guo wrote:
> spi-mtk-nor is a driver to replace mtk-quadspi and they have almost
> the same device-tree bindings. Reuse this binding documentation and
> convert it for new driver:
> 
> 1. "Mediatek SoCs" -> "Mediatek ARM SoCs" because MTK MIPS SoCs
>    use different controllers.
> 2. document "interrupts" as a required property because it's
>    available on all SoCs with this controller and new driver takes
>    advantages of it. It's implemented as optional only to maintain
>    backward compatibility.
> 3. replace binding example with a mt7629 one because this is the
>    only one I know the interrupt assignment.

That doesn't really matter. It would be less churn without that change 
and examples are just examples.

> 
> Signed-off-by: Chuanhong Guo <gch981213-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
> ---
> Change since v1:
>  none
> 
>  .../mtk-quadspi.txt => spi/spi-mtk-nor.txt}   | 34 ++++++++-----------
>  1 file changed, 15 insertions(+), 19 deletions(-)
>  rename Documentation/devicetree/bindings/{mtd/mtk-quadspi.txt => spi/spi-mtk-nor.txt} (62%)
> 
> diff --git a/Documentation/devicetree/bindings/mtd/mtk-quadspi.txt b/Documentation/devicetree/bindings/spi/spi-mtk-nor.txt
> similarity index 62%
> rename from Documentation/devicetree/bindings/mtd/mtk-quadspi.txt
> rename to Documentation/devicetree/bindings/spi/spi-mtk-nor.txt
> index a12e3b5c495d..829da480b9a9 100644
> --- a/Documentation/devicetree/bindings/mtd/mtk-quadspi.txt
> +++ b/Documentation/devicetree/bindings/spi/spi-mtk-nor.txt
> @@ -1,4 +1,4 @@
> -* Serial NOR flash controller for MediaTek SoCs
> +* SPI NOR flash controller for MediaTek ARM SoCs
>  
>  Required properties:
>  - compatible: 	  For mt8173, compatible should be "mediatek,mt8173-nor",
> @@ -13,6 +13,7 @@ Required properties:
>  		  "mediatek,mt7629-nor", "mediatek,mt8173-nor"
>  		  "mediatek,mt8173-nor"
>  - reg: 		  physical base address and length of the controller's register
> +- interrupts:	  Interrupt number used by the controller.
>  - clocks: 	  the phandle of the clocks needed by the nor controller
>  - clock-names: 	  the names of the clocks
>  		  the clocks should be named "spi" and "sf". "spi" is used for spi bus,
> @@ -22,29 +23,24 @@ Required properties:
>  - #address-cells: should be <1>
>  - #size-cells:	  should be <0>
>  
> -The SPI flash must be a child of the nor_flash node and must have a
> -compatible property. Also see jedec,spi-nor.txt.
> -
> -Required properties:
> -- compatible:	  May include a device-specific string consisting of the manufacturer
> -		  and name of the chip. Must also include "jedec,spi-nor" for any
> -		  SPI NOR flash that can be identified by the JEDEC READ ID opcode (0x9F).
> -- reg :		  Chip-Select number
> +There should be only one spi slave device following generic spi bindings.
> +It's not recommended to use this controller for devices other than SPI NOR
> +flash due to limited transfer capability of this controller.
>  
>  Example:
> +#include <dt-bindings/interrupt-controller/irq.h>
> +#include <dt-bindings/interrupt-controller/arm-gic.h>
> +#include <dt-bindings/clock/mt7629-clk.h>
>  
> -nor_flash: spi@1100d000 {
> -	compatible = "mediatek,mt8173-nor";
> -	reg = <0 0x1100d000 0 0xe0>;
> -	clocks = <&pericfg CLK_PERI_SPI>,
> -		 <&topckgen CLK_TOP_SPINFI_IFR_SEL>;
> +spi_nor: spi@11014000 {
> +	compatible = "mediatek,mt7629-nor",
> +		     "mediatek,mt8173-nor";
> +	reg = <0x11014000 0xe0>;
> +	interrupts = <GIC_SPI 88 IRQ_TYPE_LEVEL_LOW>;
> +	clocks = <&pericfg CLK_PERI_FLASH_PD>,
> +		 <&topckgen CLK_TOP_FLASH_SEL>;
>  	clock-names = "spi", "sf";
>  	#address-cells = <1>;
>  	#size-cells = <0>;
> -
> -	flash@0 {
> -		compatible = "jedec,spi-nor";
> -		reg = <0>;
> -	};

Better to leave this in the example IMO.

Rob

Re: [PATCH v2 3/4] dt-bindings: convert mtk-quadspi binding doc for spi-mtk-nor

[Chuanhong Guo]

On Wed, Mar 4, 2020 at 6:47 AM Rob Herring <robh@kernel.org> wrote:
> > 3. replace binding example with a mt7629 one because this is the
> >    only one I know the interrupt assignment.
>
> That doesn't really matter. It would be less churn without that change
> and examples are just examples.
> [...]
> > -
> > -     flash@0 {
> > -             compatible = "jedec,spi-nor";
> > -             reg = <0>;
> > -     };
>
> Better to leave this in the example IMO.
>
> Rob

I'll revert example changes and add a dummy interrupt binding instead in v3.

-- 
Regards,
Chuanhong Guo

[PATCH v2 4/4] mtd: spi-nor: remove mtk-quadspi driver

[Chuanhong Guo]

This driver is superseded by the new spi-mtk-nor driver.

Signed-off-by: Chuanhong Guo <gch981213@gmail.com>
---
Change since v1:
 new commit

 drivers/mtd/spi-nor/Kconfig       |   8 -
 drivers/mtd/spi-nor/Makefile      |   1 -
 drivers/mtd/spi-nor/mtk-quadspi.c | 565 ------------------------------
 3 files changed, 574 deletions(-)
 delete mode 100644 drivers/mtd/spi-nor/mtk-quadspi.c

diff --git a/drivers/mtd/spi-nor/Kconfig b/drivers/mtd/spi-nor/Kconfig
index c1eda67d1ad2..267b9000782e 100644
--- a/drivers/mtd/spi-nor/Kconfig
+++ b/drivers/mtd/spi-nor/Kconfig
@@ -52,14 +52,6 @@ config SPI_HISI_SFC
 	help
 	  This enables support for HiSilicon FMC SPI-NOR flash controller.
 
-config SPI_MTK_QUADSPI
-	tristate "MediaTek Quad SPI controller"
-	depends on HAS_IOMEM
-	help
-	  This enables support for the Quad SPI controller in master mode.
-	  This controller does not support generic SPI. It only supports
-	  SPI NOR.
-
 config SPI_NXP_SPIFI
 	tristate "NXP SPI Flash Interface (SPIFI)"
 	depends on OF && (ARCH_LPC18XX || COMPILE_TEST)
diff --git a/drivers/mtd/spi-nor/Makefile b/drivers/mtd/spi-nor/Makefile
index 9c5ed03cdc19..738dfd74cf76 100644
--- a/drivers/mtd/spi-nor/Makefile
+++ b/drivers/mtd/spi-nor/Makefile
@@ -3,7 +3,6 @@ obj-$(CONFIG_MTD_SPI_NOR)	+= spi-nor.o
 obj-$(CONFIG_SPI_ASPEED_SMC)	+= aspeed-smc.o
 obj-$(CONFIG_SPI_CADENCE_QUADSPI)	+= cadence-quadspi.o
 obj-$(CONFIG_SPI_HISI_SFC)	+= hisi-sfc.o
-obj-$(CONFIG_SPI_MTK_QUADSPI)    += mtk-quadspi.o
 obj-$(CONFIG_SPI_NXP_SPIFI)	+= nxp-spifi.o
 obj-$(CONFIG_SPI_INTEL_SPI)	+= intel-spi.o
 obj-$(CONFIG_SPI_INTEL_SPI_PCI)	+= intel-spi-pci.o
diff --git a/drivers/mtd/spi-nor/mtk-quadspi.c b/drivers/mtd/spi-nor/mtk-quadspi.c
deleted file mode 100644
index b1691680d174..000000000000
--- a/drivers/mtd/spi-nor/mtk-quadspi.c
+++ /dev/null
@@ -1,565 +0,0 @@
-// SPDX-License-Identifier: GPL-2.0-only
-/*
- * Copyright (c) 2015 MediaTek Inc.
- * Author: Bayi Cheng <bayi.cheng@mediatek.com>
- */
-
-#include <linux/clk.h>
-#include <linux/delay.h>
-#include <linux/device.h>
-#include <linux/init.h>
-#include <linux/io.h>
-#include <linux/iopoll.h>
-#include <linux/ioport.h>
-#include <linux/math64.h>
-#include <linux/module.h>
-#include <linux/mutex.h>
-#include <linux/of.h>
-#include <linux/of_device.h>
-#include <linux/platform_device.h>
-#include <linux/slab.h>
-#include <linux/mtd/mtd.h>
-#include <linux/mtd/partitions.h>
-#include <linux/mtd/spi-nor.h>
-
-#define MTK_NOR_CMD_REG			0x00
-#define MTK_NOR_CNT_REG			0x04
-#define MTK_NOR_RDSR_REG		0x08
-#define MTK_NOR_RDATA_REG		0x0c
-#define MTK_NOR_RADR0_REG		0x10
-#define MTK_NOR_RADR1_REG		0x14
-#define MTK_NOR_RADR2_REG		0x18
-#define MTK_NOR_WDATA_REG		0x1c
-#define MTK_NOR_PRGDATA0_REG		0x20
-#define MTK_NOR_PRGDATA1_REG		0x24
-#define MTK_NOR_PRGDATA2_REG		0x28
-#define MTK_NOR_PRGDATA3_REG		0x2c
-#define MTK_NOR_PRGDATA4_REG		0x30
-#define MTK_NOR_PRGDATA5_REG		0x34
-#define MTK_NOR_SHREG0_REG		0x38
-#define MTK_NOR_SHREG1_REG		0x3c
-#define MTK_NOR_SHREG2_REG		0x40
-#define MTK_NOR_SHREG3_REG		0x44
-#define MTK_NOR_SHREG4_REG		0x48
-#define MTK_NOR_SHREG5_REG		0x4c
-#define MTK_NOR_SHREG6_REG		0x50
-#define MTK_NOR_SHREG7_REG		0x54
-#define MTK_NOR_SHREG8_REG		0x58
-#define MTK_NOR_SHREG9_REG		0x5c
-#define MTK_NOR_CFG1_REG		0x60
-#define MTK_NOR_CFG2_REG		0x64
-#define MTK_NOR_CFG3_REG		0x68
-#define MTK_NOR_STATUS0_REG		0x70
-#define MTK_NOR_STATUS1_REG		0x74
-#define MTK_NOR_STATUS2_REG		0x78
-#define MTK_NOR_STATUS3_REG		0x7c
-#define MTK_NOR_FLHCFG_REG		0x84
-#define MTK_NOR_TIME_REG		0x94
-#define MTK_NOR_PP_DATA_REG		0x98
-#define MTK_NOR_PREBUF_STUS_REG		0x9c
-#define MTK_NOR_DELSEL0_REG		0xa0
-#define MTK_NOR_DELSEL1_REG		0xa4
-#define MTK_NOR_INTRSTUS_REG		0xa8
-#define MTK_NOR_INTREN_REG		0xac
-#define MTK_NOR_CHKSUM_CTL_REG		0xb8
-#define MTK_NOR_CHKSUM_REG		0xbc
-#define MTK_NOR_CMD2_REG		0xc0
-#define MTK_NOR_WRPROT_REG		0xc4
-#define MTK_NOR_RADR3_REG		0xc8
-#define MTK_NOR_DUAL_REG		0xcc
-#define MTK_NOR_DELSEL2_REG		0xd0
-#define MTK_NOR_DELSEL3_REG		0xd4
-#define MTK_NOR_DELSEL4_REG		0xd8
-
-/* commands for mtk nor controller */
-#define MTK_NOR_READ_CMD		0x0
-#define MTK_NOR_RDSR_CMD		0x2
-#define MTK_NOR_PRG_CMD			0x4
-#define MTK_NOR_WR_CMD			0x10
-#define MTK_NOR_PIO_WR_CMD		0x90
-#define MTK_NOR_WRSR_CMD		0x20
-#define MTK_NOR_PIO_READ_CMD		0x81
-#define MTK_NOR_WR_BUF_ENABLE		0x1
-#define MTK_NOR_WR_BUF_DISABLE		0x0
-#define MTK_NOR_ENABLE_SF_CMD		0x30
-#define MTK_NOR_DUAD_ADDR_EN		0x8
-#define MTK_NOR_QUAD_READ_EN		0x4
-#define MTK_NOR_DUAL_ADDR_EN		0x2
-#define MTK_NOR_DUAL_READ_EN		0x1
-#define MTK_NOR_DUAL_DISABLE		0x0
-#define MTK_NOR_FAST_READ		0x1
-
-#define SFLASH_WRBUF_SIZE		128
-
-/* Can shift up to 48 bits (6 bytes) of TX/RX */
-#define MTK_NOR_MAX_RX_TX_SHIFT		6
-/* can shift up to 56 bits (7 bytes) transfer by MTK_NOR_PRG_CMD */
-#define MTK_NOR_MAX_SHIFT		7
-/* nor controller 4-byte address mode enable bit */
-#define MTK_NOR_4B_ADDR_EN		BIT(4)
-
-/* Helpers for accessing the program data / shift data registers */
-#define MTK_NOR_PRG_REG(n)		(MTK_NOR_PRGDATA0_REG + 4 * (n))
-#define MTK_NOR_SHREG(n)		(MTK_NOR_SHREG0_REG + 4 * (n))
-
-struct mtk_nor {
-	struct spi_nor nor;
-	struct device *dev;
-	void __iomem *base;	/* nor flash base address */
-	struct clk *spi_clk;
-	struct clk *nor_clk;
-};
-
-static void mtk_nor_set_read_mode(struct mtk_nor *mtk_nor)
-{
-	struct spi_nor *nor = &mtk_nor->nor;
-
-	switch (nor->read_proto) {
-	case SNOR_PROTO_1_1_1:
-		writeb(nor->read_opcode, mtk_nor->base +
-		       MTK_NOR_PRGDATA3_REG);
-		writeb(MTK_NOR_FAST_READ, mtk_nor->base +
-		       MTK_NOR_CFG1_REG);
-		break;
-	case SNOR_PROTO_1_1_2:
-		writeb(nor->read_opcode, mtk_nor->base +
-		       MTK_NOR_PRGDATA3_REG);
-		writeb(MTK_NOR_DUAL_READ_EN, mtk_nor->base +
-		       MTK_NOR_DUAL_REG);
-		break;
-	case SNOR_PROTO_1_1_4:
-		writeb(nor->read_opcode, mtk_nor->base +
-		       MTK_NOR_PRGDATA4_REG);
-		writeb(MTK_NOR_QUAD_READ_EN, mtk_nor->base +
-		       MTK_NOR_DUAL_REG);
-		break;
-	default:
-		writeb(MTK_NOR_DUAL_DISABLE, mtk_nor->base +
-		       MTK_NOR_DUAL_REG);
-		break;
-	}
-}
-
-static int mtk_nor_execute_cmd(struct mtk_nor *mtk_nor, u8 cmdval)
-{
-	int reg;
-	u8 val = cmdval & 0x1f;
-
-	writeb(cmdval, mtk_nor->base + MTK_NOR_CMD_REG);
-	return readl_poll_timeout(mtk_nor->base + MTK_NOR_CMD_REG, reg,
-				  !(reg & val), 100, 10000);
-}
-
-static int mtk_nor_do_tx_rx(struct mtk_nor *mtk_nor, u8 op,
-			    const u8 *tx, size_t txlen, u8 *rx, size_t rxlen)
-{
-	size_t len = 1 + txlen + rxlen;
-	int i, ret, idx;
-
-	if (len > MTK_NOR_MAX_SHIFT)
-		return -EINVAL;
-
-	writeb(len * 8, mtk_nor->base + MTK_NOR_CNT_REG);
-
-	/* start at PRGDATA5, go down to PRGDATA0 */
-	idx = MTK_NOR_MAX_RX_TX_SHIFT - 1;
-
-	/* opcode */
-	writeb(op, mtk_nor->base + MTK_NOR_PRG_REG(idx));
-	idx--;
-
-	/* program TX data */
-	for (i = 0; i < txlen; i++, idx--)
-		writeb(tx[i], mtk_nor->base + MTK_NOR_PRG_REG(idx));
-
-	/* clear out rest of TX registers */
-	while (idx >= 0) {
-		writeb(0, mtk_nor->base + MTK_NOR_PRG_REG(idx));
-		idx--;
-	}
-
-	ret = mtk_nor_execute_cmd(mtk_nor, MTK_NOR_PRG_CMD);
-	if (ret)
-		return ret;
-
-	/* restart at first RX byte */
-	idx = rxlen - 1;
-
-	/* read out RX data */
-	for (i = 0; i < rxlen; i++, idx--)
-		rx[i] = readb(mtk_nor->base + MTK_NOR_SHREG(idx));
-
-	return 0;
-}
-
-/* Do a WRSR (Write Status Register) command */
-static int mtk_nor_wr_sr(struct mtk_nor *mtk_nor, const u8 sr)
-{
-	writeb(sr, mtk_nor->base + MTK_NOR_PRGDATA5_REG);
-	writeb(8, mtk_nor->base + MTK_NOR_CNT_REG);
-	return mtk_nor_execute_cmd(mtk_nor, MTK_NOR_WRSR_CMD);
-}
-
-static int mtk_nor_write_buffer_enable(struct mtk_nor *mtk_nor)
-{
-	u8 reg;
-
-	/* the bit0 of MTK_NOR_CFG2_REG is pre-fetch buffer
-	 * 0: pre-fetch buffer use for read
-	 * 1: pre-fetch buffer use for page program
-	 */
-	writel(MTK_NOR_WR_BUF_ENABLE, mtk_nor->base + MTK_NOR_CFG2_REG);
-	return readb_poll_timeout(mtk_nor->base + MTK_NOR_CFG2_REG, reg,
-				  0x01 == (reg & 0x01), 100, 10000);
-}
-
-static int mtk_nor_write_buffer_disable(struct mtk_nor *mtk_nor)
-{
-	u8 reg;
-
-	writel(MTK_NOR_WR_BUF_DISABLE, mtk_nor->base + MTK_NOR_CFG2_REG);
-	return readb_poll_timeout(mtk_nor->base + MTK_NOR_CFG2_REG, reg,
-				  MTK_NOR_WR_BUF_DISABLE == (reg & 0x1), 100,
-				  10000);
-}
-
-static void mtk_nor_set_addr_width(struct mtk_nor *mtk_nor)
-{
-	u8 val;
-	struct spi_nor *nor = &mtk_nor->nor;
-
-	val = readb(mtk_nor->base + MTK_NOR_DUAL_REG);
-
-	switch (nor->addr_width) {
-	case 3:
-		val &= ~MTK_NOR_4B_ADDR_EN;
-		break;
-	case 4:
-		val |= MTK_NOR_4B_ADDR_EN;
-		break;
-	default:
-		dev_warn(mtk_nor->dev, "Unexpected address width %u.\n",
-			 nor->addr_width);
-		break;
-	}
-
-	writeb(val, mtk_nor->base + MTK_NOR_DUAL_REG);
-}
-
-static void mtk_nor_set_addr(struct mtk_nor *mtk_nor, u32 addr)
-{
-	int i;
-
-	mtk_nor_set_addr_width(mtk_nor);
-
-	for (i = 0; i < 3; i++) {
-		writeb(addr & 0xff, mtk_nor->base + MTK_NOR_RADR0_REG + i * 4);
-		addr >>= 8;
-	}
-	/* Last register is non-contiguous */
-	writeb(addr & 0xff, mtk_nor->base + MTK_NOR_RADR3_REG);
-}
-
-static ssize_t mtk_nor_read(struct spi_nor *nor, loff_t from, size_t length,
-			    u_char *buffer)
-{
-	int i, ret;
-	int addr = (int)from;
-	u8 *buf = (u8 *)buffer;
-	struct mtk_nor *mtk_nor = nor->priv;
-
-	/* set mode for fast read mode ,dual mode or quad mode */
-	mtk_nor_set_read_mode(mtk_nor);
-	mtk_nor_set_addr(mtk_nor, addr);
-
-	for (i = 0; i < length; i++) {
-		ret = mtk_nor_execute_cmd(mtk_nor, MTK_NOR_PIO_READ_CMD);
-		if (ret < 0)
-			return ret;
-		buf[i] = readb(mtk_nor->base + MTK_NOR_RDATA_REG);
-	}
-	return length;
-}
-
-static int mtk_nor_write_single_byte(struct mtk_nor *mtk_nor,
-				     int addr, int length, u8 *data)
-{
-	int i, ret;
-
-	mtk_nor_set_addr(mtk_nor, addr);
-
-	for (i = 0; i < length; i++) {
-		writeb(*data++, mtk_nor->base + MTK_NOR_WDATA_REG);
-		ret = mtk_nor_execute_cmd(mtk_nor, MTK_NOR_PIO_WR_CMD);
-		if (ret < 0)
-			return ret;
-	}
-	return 0;
-}
-
-static int mtk_nor_write_buffer(struct mtk_nor *mtk_nor, int addr,
-				const u8 *buf)
-{
-	int i, bufidx, data;
-
-	mtk_nor_set_addr(mtk_nor, addr);
-
-	bufidx = 0;
-	for (i = 0; i < SFLASH_WRBUF_SIZE; i += 4) {
-		data = buf[bufidx + 3]<<24 | buf[bufidx + 2]<<16 |
-		       buf[bufidx + 1]<<8 | buf[bufidx];
-		bufidx += 4;
-		writel(data, mtk_nor->base + MTK_NOR_PP_DATA_REG);
-	}
-	return mtk_nor_execute_cmd(mtk_nor, MTK_NOR_WR_CMD);
-}
-
-static ssize_t mtk_nor_write(struct spi_nor *nor, loff_t to, size_t len,
-			     const u_char *buf)
-{
-	int ret;
-	struct mtk_nor *mtk_nor = nor->priv;
-	size_t i;
-
-	ret = mtk_nor_write_buffer_enable(mtk_nor);
-	if (ret < 0) {
-		dev_warn(mtk_nor->dev, "write buffer enable failed!\n");
-		return ret;
-	}
-
-	for (i = 0; i + SFLASH_WRBUF_SIZE <= len; i += SFLASH_WRBUF_SIZE) {
-		ret = mtk_nor_write_buffer(mtk_nor, to, buf);
-		if (ret < 0) {
-			dev_err(mtk_nor->dev, "write buffer failed!\n");
-			return ret;
-		}
-		to += SFLASH_WRBUF_SIZE;
-		buf += SFLASH_WRBUF_SIZE;
-	}
-	ret = mtk_nor_write_buffer_disable(mtk_nor);
-	if (ret < 0) {
-		dev_warn(mtk_nor->dev, "write buffer disable failed!\n");
-		return ret;
-	}
-
-	if (i < len) {
-		ret = mtk_nor_write_single_byte(mtk_nor, to,
-						(int)(len - i), (u8 *)buf);
-		if (ret < 0) {
-			dev_err(mtk_nor->dev, "write single byte failed!\n");
-			return ret;
-		}
-	}
-
-	return len;
-}
-
-static int mtk_nor_read_reg(struct spi_nor *nor, u8 opcode, u8 *buf, size_t len)
-{
-	int ret;
-	struct mtk_nor *mtk_nor = nor->priv;
-
-	switch (opcode) {
-	case SPINOR_OP_RDSR:
-		ret = mtk_nor_execute_cmd(mtk_nor, MTK_NOR_RDSR_CMD);
-		if (ret < 0)
-			return ret;
-		if (len == 1)
-			*buf = readb(mtk_nor->base + MTK_NOR_RDSR_REG);
-		else
-			dev_err(mtk_nor->dev, "len should be 1 for read status!\n");
-		break;
-	default:
-		ret = mtk_nor_do_tx_rx(mtk_nor, opcode, NULL, 0, buf, len);
-		break;
-	}
-	return ret;
-}
-
-static int mtk_nor_write_reg(struct spi_nor *nor, u8 opcode, const u8 *buf,
-			     size_t len)
-{
-	int ret;
-	struct mtk_nor *mtk_nor = nor->priv;
-
-	switch (opcode) {
-	case SPINOR_OP_WRSR:
-		/* We only handle 1 byte */
-		ret = mtk_nor_wr_sr(mtk_nor, *buf);
-		break;
-	default:
-		ret = mtk_nor_do_tx_rx(mtk_nor, opcode, buf, len, NULL, 0);
-		if (ret)
-			dev_warn(mtk_nor->dev, "write reg failure!\n");
-		break;
-	}
-	return ret;
-}
-
-static void mtk_nor_disable_clk(struct mtk_nor *mtk_nor)
-{
-	clk_disable_unprepare(mtk_nor->spi_clk);
-	clk_disable_unprepare(mtk_nor->nor_clk);
-}
-
-static int mtk_nor_enable_clk(struct mtk_nor *mtk_nor)
-{
-	int ret;
-
-	ret = clk_prepare_enable(mtk_nor->spi_clk);
-	if (ret)
-		return ret;
-
-	ret = clk_prepare_enable(mtk_nor->nor_clk);
-	if (ret) {
-		clk_disable_unprepare(mtk_nor->spi_clk);
-		return ret;
-	}
-
-	return 0;
-}
-
-static const struct spi_nor_controller_ops mtk_controller_ops = {
-	.read_reg = mtk_nor_read_reg,
-	.write_reg = mtk_nor_write_reg,
-	.read = mtk_nor_read,
-	.write = mtk_nor_write,
-};
-
-static int mtk_nor_init(struct mtk_nor *mtk_nor,
-			struct device_node *flash_node)
-{
-	const struct spi_nor_hwcaps hwcaps = {
-		.mask = SNOR_HWCAPS_READ |
-			SNOR_HWCAPS_READ_FAST |
-			SNOR_HWCAPS_READ_1_1_2 |
-			SNOR_HWCAPS_PP,
-	};
-	int ret;
-	struct spi_nor *nor;
-
-	/* initialize controller to accept commands */
-	writel(MTK_NOR_ENABLE_SF_CMD, mtk_nor->base + MTK_NOR_WRPROT_REG);
-
-	nor = &mtk_nor->nor;
-	nor->dev = mtk_nor->dev;
-	nor->priv = mtk_nor;
-	spi_nor_set_flash_node(nor, flash_node);
-	nor->controller_ops = &mtk_controller_ops;
-
-	nor->mtd.name = "mtk_nor";
-	/* initialized with NULL */
-	ret = spi_nor_scan(nor, NULL, &hwcaps);
-	if (ret)
-		return ret;
-
-	return mtd_device_register(&nor->mtd, NULL, 0);
-}
-
-static int mtk_nor_drv_probe(struct platform_device *pdev)
-{
-	struct device_node *flash_np;
-	struct resource *res;
-	int ret;
-	struct mtk_nor *mtk_nor;
-
-	if (!pdev->dev.of_node) {
-		dev_err(&pdev->dev, "No DT found\n");
-		return -EINVAL;
-	}
-
-	mtk_nor = devm_kzalloc(&pdev->dev, sizeof(*mtk_nor), GFP_KERNEL);
-	if (!mtk_nor)
-		return -ENOMEM;
-	platform_set_drvdata(pdev, mtk_nor);
-
-	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
-	mtk_nor->base = devm_ioremap_resource(&pdev->dev, res);
-	if (IS_ERR(mtk_nor->base))
-		return PTR_ERR(mtk_nor->base);
-
-	mtk_nor->spi_clk = devm_clk_get(&pdev->dev, "spi");
-	if (IS_ERR(mtk_nor->spi_clk))
-		return PTR_ERR(mtk_nor->spi_clk);
-
-	mtk_nor->nor_clk = devm_clk_get(&pdev->dev, "sf");
-	if (IS_ERR(mtk_nor->nor_clk))
-		return PTR_ERR(mtk_nor->nor_clk);
-
-	mtk_nor->dev = &pdev->dev;
-
-	ret = mtk_nor_enable_clk(mtk_nor);
-	if (ret)
-		return ret;
-
-	/* only support one attached flash */
-	flash_np = of_get_next_available_child(pdev->dev.of_node, NULL);
-	if (!flash_np) {
-		dev_err(&pdev->dev, "no SPI flash device to configure\n");
-		ret = -ENODEV;
-		goto nor_free;
-	}
-	ret = mtk_nor_init(mtk_nor, flash_np);
-
-nor_free:
-	if (ret)
-		mtk_nor_disable_clk(mtk_nor);
-
-	return ret;
-}
-
-static int mtk_nor_drv_remove(struct platform_device *pdev)
-{
-	struct mtk_nor *mtk_nor = platform_get_drvdata(pdev);
-
-	mtk_nor_disable_clk(mtk_nor);
-
-	return 0;
-}
-
-#ifdef CONFIG_PM_SLEEP
-static int mtk_nor_suspend(struct device *dev)
-{
-	struct mtk_nor *mtk_nor = dev_get_drvdata(dev);
-
-	mtk_nor_disable_clk(mtk_nor);
-
-	return 0;
-}
-
-static int mtk_nor_resume(struct device *dev)
-{
-	struct mtk_nor *mtk_nor = dev_get_drvdata(dev);
-
-	return mtk_nor_enable_clk(mtk_nor);
-}
-
-static const struct dev_pm_ops mtk_nor_dev_pm_ops = {
-	.suspend = mtk_nor_suspend,
-	.resume = mtk_nor_resume,
-};
-
-#define MTK_NOR_DEV_PM_OPS	(&mtk_nor_dev_pm_ops)
-#else
-#define MTK_NOR_DEV_PM_OPS	NULL
-#endif
-
-static const struct of_device_id mtk_nor_of_ids[] = {
-	{ .compatible = "mediatek,mt8173-nor"},
-	{ /* sentinel */ }
-};
-MODULE_DEVICE_TABLE(of, mtk_nor_of_ids);
-
-static struct platform_driver mtk_nor_driver = {
-	.probe = mtk_nor_drv_probe,
-	.remove = mtk_nor_drv_remove,
-	.driver = {
-		.name = "mtk-nor",
-		.pm = MTK_NOR_DEV_PM_OPS,
-		.of_match_table = mtk_nor_of_ids,
-	},
-};
-
-module_platform_driver(mtk_nor_driver);
-MODULE_LICENSE("GPL v2");
-MODULE_DESCRIPTION("MediaTek SPI NOR Flash Driver");
-- 
2.24.1