drivers/mtd/spi-nor/hisi-sfc.c - linux - Git at Google

 // SPDX-License-Identifier: GPL-2.0-or-later
 /*
  * HiSilicon SPI Nor Flash Controller Driver
  *
  * Copyright (c) 2015-2016 HiSilicon Technologies Co., Ltd.
  */
 #include <linux/bitops.h>
 #include <linux/clk.h>
 #include <linux/dma-mapping.h>
 #include <linux/iopoll.h>
 #include <linux/module.h>
 #include <linux/mtd/mtd.h>
 #include <linux/mtd/spi-nor.h>
 #include <linux/of.h>
 #include <linux/platform_device.h>
 #include <linux/slab.h>

 /* Hardware register offsets and field definitions */
 #define FMC_CFG				0x00
 #define FMC_CFG_OP_MODE_MASK		BIT_MASK(0)
 #define FMC_CFG_OP_MODE_BOOT		0
 #define FMC_CFG_OP_MODE_NORMAL		1
 #define FMC_CFG_FLASH_SEL(type)		(((type) & 0x3) << 1)
 #define FMC_CFG_FLASH_SEL_MASK		0x6
 #define FMC_ECC_TYPE(type)		(((type) & 0x7) << 5)
 #define FMC_ECC_TYPE_MASK		GENMASK(7, 5)
 #define SPI_NOR_ADDR_MODE_MASK		BIT_MASK(10)
 #define SPI_NOR_ADDR_MODE_3BYTES	(0x0 << 10)
 #define SPI_NOR_ADDR_MODE_4BYTES	(0x1 << 10)
 #define FMC_GLOBAL_CFG			0x04
 #define FMC_GLOBAL_CFG_WP_ENABLE	BIT(6)
 #define FMC_SPI_TIMING_CFG		0x08
 #define TIMING_CFG_TCSH(nr)		(((nr) & 0xf) << 8)
 #define TIMING_CFG_TCSS(nr)		(((nr) & 0xf) << 4)
 #define TIMING_CFG_TSHSL(nr)		((nr) & 0xf)
 #define CS_HOLD_TIME			0x6
 #define CS_SETUP_TIME			0x6
 #define CS_DESELECT_TIME		0xf
 #define FMC_INT				0x18
 #define FMC_INT_OP_DONE			BIT(0)
 #define FMC_INT_CLR			0x20
 #define FMC_CMD				0x24
 #define FMC_CMD_CMD1(cmd)		((cmd) & 0xff)
 #define FMC_ADDRL			0x2c
 #define FMC_OP_CFG			0x30
 #define OP_CFG_FM_CS(cs)		((cs) << 11)
 #define OP_CFG_MEM_IF_TYPE(type)	(((type) & 0x7) << 7)
 #define OP_CFG_ADDR_NUM(addr)		(((addr) & 0x7) << 4)
 #define OP_CFG_DUMMY_NUM(dummy)		((dummy) & 0xf)
 #define FMC_DATA_NUM			0x38
 #define FMC_DATA_NUM_CNT(cnt)		((cnt) & GENMASK(13, 0))
 #define FMC_OP				0x3c
 #define FMC_OP_DUMMY_EN			BIT(8)
 #define FMC_OP_CMD1_EN			BIT(7)
 #define FMC_OP_ADDR_EN			BIT(6)
 #define FMC_OP_WRITE_DATA_EN		BIT(5)
 #define FMC_OP_READ_DATA_EN		BIT(2)
 #define FMC_OP_READ_STATUS_EN		BIT(1)
 #define FMC_OP_REG_OP_START		BIT(0)
 #define FMC_DMA_LEN			0x40
 #define FMC_DMA_LEN_SET(len)		((len) & GENMASK(27, 0))
 #define FMC_DMA_SADDR_D0		0x4c
 #define HIFMC_DMA_MAX_LEN		(4096)
 #define HIFMC_DMA_MASK			(HIFMC_DMA_MAX_LEN - 1)
 #define FMC_OP_DMA			0x68
 #define OP_CTRL_RD_OPCODE(code)		(((code) & 0xff) << 16)
 #define OP_CTRL_WR_OPCODE(code)		(((code) & 0xff) << 8)
 #define OP_CTRL_RW_OP(op)		((op) << 1)
 #define OP_CTRL_DMA_OP_READY		BIT(0)
 #define FMC_OP_READ			0x0
 #define FMC_OP_WRITE			0x1
 #define FMC_WAIT_TIMEOUT		1000000

 enum hifmc_iftype {
 	IF_TYPE_STD,
 	IF_TYPE_DUAL,
 	IF_TYPE_DIO,
 	IF_TYPE_QUAD,
 	IF_TYPE_QIO,
 };

 struct hifmc_priv {
 	u32 chipselect;
 	u32 clkrate;
 	struct hifmc_host *host;
 };

 #define HIFMC_MAX_CHIP_NUM		2
 struct hifmc_host {
 	struct device *dev;
 	struct mutex lock;

 	void __iomem *regbase;
 	void __iomem *iobase;
 	struct clk *clk;
 	void *buffer;
 	dma_addr_t dma_buffer;

 	struct spi_nor	*nor[HIFMC_MAX_CHIP_NUM];
 	u32 num_chip;
 };

 static inline int hisi_spi_nor_wait_op_finish(struct hifmc_host *host)
 {
 	u32 reg;

 	return readl_poll_timeout(host->regbase + FMC_INT, reg,
 		(reg & FMC_INT_OP_DONE), 0, FMC_WAIT_TIMEOUT);
 }

 static int hisi_spi_nor_get_if_type(enum spi_nor_protocol proto)
 {
 	enum hifmc_iftype if_type;

 	switch (proto) {
 	case SNOR_PROTO_1_1_2:
 		if_type = IF_TYPE_DUAL;
 		break;
 	case SNOR_PROTO_1_2_2:
 		if_type = IF_TYPE_DIO;
 		break;
 	case SNOR_PROTO_1_1_4:
 		if_type = IF_TYPE_QUAD;
 		break;
 	case SNOR_PROTO_1_4_4:
 		if_type = IF_TYPE_QIO;
 		break;
 	case SNOR_PROTO_1_1_1:
 	default:
 		if_type = IF_TYPE_STD;
 		break;
 	}

 	return if_type;
 }

 static void hisi_spi_nor_init(struct hifmc_host *host)
 {
 	u32 reg;

 	reg = TIMING_CFG_TCSH(CS_HOLD_TIME)
 		| TIMING_CFG_TCSS(CS_SETUP_TIME)
 		| TIMING_CFG_TSHSL(CS_DESELECT_TIME);
 	writel(reg, host->regbase + FMC_SPI_TIMING_CFG);
 }

 static int hisi_spi_nor_prep(struct spi_nor *nor, enum spi_nor_ops ops)
 {
 	struct hifmc_priv *priv = nor->priv;
 	struct hifmc_host *host = priv->host;
 	int ret;

 	mutex_lock(&host->lock);

 	ret = clk_set_rate(host->clk, priv->clkrate);
 	if (ret)
 		goto out;

 	ret = clk_prepare_enable(host->clk);
 	if (ret)
 		goto out;

 	return 0;

 out:
 	mutex_unlock(&host->lock);
 	return ret;
 }

 static void hisi_spi_nor_unprep(struct spi_nor *nor, enum spi_nor_ops ops)
 {
 	struct hifmc_priv *priv = nor->priv;
 	struct hifmc_host *host = priv->host;

 	clk_disable_unprepare(host->clk);
 	mutex_unlock(&host->lock);
 }

 static int hisi_spi_nor_op_reg(struct spi_nor *nor,
 				u8 opcode, int len, u8 optype)
 {
 	struct hifmc_priv *priv = nor->priv;
 	struct hifmc_host *host = priv->host;
 	u32 reg;

 	reg = FMC_CMD_CMD1(opcode);
 	writel(reg, host->regbase + FMC_CMD);

 	reg = FMC_DATA_NUM_CNT(len);
 	writel(reg, host->regbase + FMC_DATA_NUM);

 	reg = OP_CFG_FM_CS(priv->chipselect);
 	writel(reg, host->regbase + FMC_OP_CFG);

 	writel(0xff, host->regbase + FMC_INT_CLR);
 	reg = FMC_OP_CMD1_EN | FMC_OP_REG_OP_START | optype;
 	writel(reg, host->regbase + FMC_OP);

 	return hisi_spi_nor_wait_op_finish(host);
 }

 static int hisi_spi_nor_read_reg(struct spi_nor *nor, u8 opcode, u8 *buf,
 		int len)
 {
 	struct hifmc_priv *priv = nor->priv;
 	struct hifmc_host *host = priv->host;
 	int ret;

 	ret = hisi_spi_nor_op_reg(nor, opcode, len, FMC_OP_READ_DATA_EN);
 	if (ret)
 		return ret;

 	memcpy_fromio(buf, host->iobase, len);
 	return 0;
 }

 static int hisi_spi_nor_write_reg(struct spi_nor *nor, u8 opcode,
 				u8 *buf, int len)
 {
 	struct hifmc_priv *priv = nor->priv;
 	struct hifmc_host *host = priv->host;

 	if (len)
 		memcpy_toio(host->iobase, buf, len);

 	return hisi_spi_nor_op_reg(nor, opcode, len, FMC_OP_WRITE_DATA_EN);
 }

 static int hisi_spi_nor_dma_transfer(struct spi_nor *nor, loff_t start_off,
 		dma_addr_t dma_buf, size_t len, u8 op_type)
 {
 	struct hifmc_priv *priv = nor->priv;
 	struct hifmc_host *host = priv->host;
 	u8 if_type = 0;
 	u32 reg;

 	reg = readl(host->regbase + FMC_CFG);
 	reg &= ~(FMC_CFG_OP_MODE_MASK | SPI_NOR_ADDR_MODE_MASK);
 	reg |= FMC_CFG_OP_MODE_NORMAL;
 	reg |= (nor->addr_width == 4) ? SPI_NOR_ADDR_MODE_4BYTES
 		: SPI_NOR_ADDR_MODE_3BYTES;
 	writel(reg, host->regbase + FMC_CFG);

 	writel(start_off, host->regbase + FMC_ADDRL);
 	writel(dma_buf, host->regbase + FMC_DMA_SADDR_D0);
 	writel(FMC_DMA_LEN_SET(len), host->regbase + FMC_DMA_LEN);

 	reg = OP_CFG_FM_CS(priv->chipselect);
 	if (op_type == FMC_OP_READ)
 		if_type = hisi_spi_nor_get_if_type(nor->read_proto);
 	else
 		if_type = hisi_spi_nor_get_if_type(nor->write_proto);
 	reg |= OP_CFG_MEM_IF_TYPE(if_type);
 	if (op_type == FMC_OP_READ)
 		reg |= OP_CFG_DUMMY_NUM(nor->read_dummy >> 3);
 	writel(reg, host->regbase + FMC_OP_CFG);

 	writel(0xff, host->regbase + FMC_INT_CLR);
 	reg = OP_CTRL_RW_OP(op_type) | OP_CTRL_DMA_OP_READY;
 	reg |= (op_type == FMC_OP_READ)
 		? OP_CTRL_RD_OPCODE(nor->read_opcode)
 		: OP_CTRL_WR_OPCODE(nor->program_opcode);
 	writel(reg, host->regbase + FMC_OP_DMA);

 	return hisi_spi_nor_wait_op_finish(host);
 }

 static ssize_t hisi_spi_nor_read(struct spi_nor *nor, loff_t from, size_t len,
 		u_char *read_buf)
 {
 	struct hifmc_priv *priv = nor->priv;
 	struct hifmc_host *host = priv->host;
 	size_t offset;
 	int ret;

 	for (offset = 0; offset < len; offset += HIFMC_DMA_MAX_LEN) {
 		size_t trans = min_t(size_t, HIFMC_DMA_MAX_LEN, len - offset);

 		ret = hisi_spi_nor_dma_transfer(nor,
 			from + offset, host->dma_buffer, trans, FMC_OP_READ);
 		if (ret) {
 			dev_warn(nor->dev, "DMA read timeout\n");
 			return ret;
 		}
 		memcpy(read_buf + offset, host->buffer, trans);
 	}

 	return len;
 }

 static ssize_t hisi_spi_nor_write(struct spi_nor *nor, loff_t to,
 			size_t len, const u_char *write_buf)
 {
 	struct hifmc_priv *priv = nor->priv;
 	struct hifmc_host *host = priv->host;
 	size_t offset;
 	int ret;

 	for (offset = 0; offset < len; offset += HIFMC_DMA_MAX_LEN) {
 		size_t trans = min_t(size_t, HIFMC_DMA_MAX_LEN, len - offset);

 		memcpy(host->buffer, write_buf + offset, trans);
 		ret = hisi_spi_nor_dma_transfer(nor,
 			to + offset, host->dma_buffer, trans, FMC_OP_WRITE);
 		if (ret) {
 			dev_warn(nor->dev, "DMA write timeout\n");
 			return ret;
 		}
 	}

 	return len;
 }

 /**
  * Get spi flash device information and register it as a mtd device.
  */
 static int hisi_spi_nor_register(struct device_node *np,
 				struct hifmc_host *host)
 {
 	const struct spi_nor_hwcaps hwcaps = {
 		.mask = SNOR_HWCAPS_READ |
 			SNOR_HWCAPS_READ_FAST |
 			SNOR_HWCAPS_READ_1_1_2 |
 			SNOR_HWCAPS_READ_1_1_4 |
 			SNOR_HWCAPS_PP,
 	};
 	struct device *dev = host->dev;
 	struct spi_nor *nor;
 	struct hifmc_priv *priv;
 	struct mtd_info *mtd;
 	int ret;

 	nor = devm_kzalloc(dev, sizeof(*nor), GFP_KERNEL);
 	if (!nor)
 		return -ENOMEM;

 	nor->dev = dev;
 	spi_nor_set_flash_node(nor, np);

 	priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
 	if (!priv)
 		return -ENOMEM;

 	ret = of_property_read_u32(np, "reg", &priv->chipselect);
 	if (ret) {
 		dev_err(dev, "There's no reg property for %pOF\n",
 			np);
 		return ret;
 	}

 	ret = of_property_read_u32(np, "spi-max-frequency",
 			&priv->clkrate);
 	if (ret) {
 		dev_err(dev, "There's no spi-max-frequency property for %pOF\n",
 			np);
 		return ret;
 	}
 	priv->host = host;
 	nor->priv = priv;

 	nor->prepare = hisi_spi_nor_prep;
 	nor->unprepare = hisi_spi_nor_unprep;
 	nor->read_reg = hisi_spi_nor_read_reg;
 	nor->write_reg = hisi_spi_nor_write_reg;
 	nor->read = hisi_spi_nor_read;
 	nor->write = hisi_spi_nor_write;
 	nor->erase = NULL;
 	ret = spi_nor_scan(nor, NULL, &hwcaps);
 	if (ret)
 		return ret;

 	mtd = &nor->mtd;
 	mtd->name = np->name;
 	ret = mtd_device_register(mtd, NULL, 0);
 	if (ret)
 		return ret;

 	host->nor[host->num_chip] = nor;
 	host->num_chip++;
 	return 0;
 }

 static void hisi_spi_nor_unregister_all(struct hifmc_host *host)
 {
 	int i;

 	for (i = 0; i < host->num_chip; i++)
 		mtd_device_unregister(&host->nor[i]->mtd);
 }

 static int hisi_spi_nor_register_all(struct hifmc_host *host)
 {
 	struct device *dev = host->dev;
 	struct device_node *np;
 	int ret;

 	for_each_available_child_of_node(dev->of_node, np) {
 		ret = hisi_spi_nor_register(np, host);
 		if (ret)
 			goto fail;

 		if (host->num_chip == HIFMC_MAX_CHIP_NUM) {
 			dev_warn(dev, "Flash device number exceeds the maximum chipselect number\n");
 			of_node_put(np);
 			break;
 		}
 	}

 	return 0;

 fail:
 	hisi_spi_nor_unregister_all(host);
 	return ret;
 }

 static int hisi_spi_nor_probe(struct platform_device *pdev)
 {
 	struct device *dev = &pdev->dev;
 	struct resource *res;
 	struct hifmc_host *host;
 	int ret;

 	host = devm_kzalloc(dev, sizeof(*host), GFP_KERNEL);
 	if (!host)
 		return -ENOMEM;

 	platform_set_drvdata(pdev, host);
 	host->dev = dev;

 	res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "control");
 	host->regbase = devm_ioremap_resource(dev, res);
 	if (IS_ERR(host->regbase))
 		return PTR_ERR(host->regbase);

 	res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "memory");
 	host->iobase = devm_ioremap_resource(dev, res);
 	if (IS_ERR(host->iobase))
 		return PTR_ERR(host->iobase);

 	host->clk = devm_clk_get(dev, NULL);
 	if (IS_ERR(host->clk))
 		return PTR_ERR(host->clk);

 	ret = dma_set_mask_and_coherent(dev, DMA_BIT_MASK(32));
 	if (ret) {
 		dev_warn(dev, "Unable to set dma mask\n");
 		return ret;
 	}

 	host->buffer = dmam_alloc_coherent(dev, HIFMC_DMA_MAX_LEN,
 			&host->dma_buffer, GFP_KERNEL);
 	if (!host->buffer)
 		return -ENOMEM;

 	ret = clk_prepare_enable(host->clk);
 	if (ret)
 		return ret;

 	mutex_init(&host->lock);
 	hisi_spi_nor_init(host);
 	ret = hisi_spi_nor_register_all(host);
 	if (ret)
 		mutex_destroy(&host->lock);

 	clk_disable_unprepare(host->clk);
 	return ret;
 }

 static int hisi_spi_nor_remove(struct platform_device *pdev)
 {
 	struct hifmc_host *host = platform_get_drvdata(pdev);

 	hisi_spi_nor_unregister_all(host);
 	mutex_destroy(&host->lock);
 	clk_disable_unprepare(host->clk);
 	return 0;
 }

 static const struct of_device_id hisi_spi_nor_dt_ids[] = {
 	{ .compatible = "hisilicon,fmc-spi-nor"},
 	{ /* sentinel */ }
 };
 MODULE_DEVICE_TABLE(of, hisi_spi_nor_dt_ids);

 static struct platform_driver hisi_spi_nor_driver = {
 	.driver = {
 		.name	= "hisi-sfc",
 		.of_match_table = hisi_spi_nor_dt_ids,
 	},
 	.probe	= hisi_spi_nor_probe,
 	.remove	= hisi_spi_nor_remove,
 };
 module_platform_driver(hisi_spi_nor_driver);

 MODULE_LICENSE("GPL v2");
 MODULE_DESCRIPTION("HiSilicon SPI Nor Flash Controller Driver");
	// SPDX-License-Identifier: GPL-2.0-or-later
	/*
	* HiSilicon SPI Nor Flash Controller Driver
	*
	* Copyright (c) 2015-2016 HiSilicon Technologies Co., Ltd.
	*/
	#include <linux/bitops.h>
	#include <linux/clk.h>
	#include <linux/dma-mapping.h>
	#include <linux/iopoll.h>
	#include <linux/module.h>
	#include <linux/mtd/mtd.h>
	#include <linux/mtd/spi-nor.h>
	#include <linux/of.h>
	#include <linux/platform_device.h>
	#include <linux/slab.h>

	/* Hardware register offsets and field definitions */
	#define FMC_CFG 0x00
	#define FMC_CFG_OP_MODE_MASK BIT_MASK(0)
	#define FMC_CFG_OP_MODE_BOOT 0
	#define FMC_CFG_OP_MODE_NORMAL 1
	#define FMC_CFG_FLASH_SEL(type) (((type) & 0x3) << 1)
	#define FMC_CFG_FLASH_SEL_MASK 0x6
	#define FMC_ECC_TYPE(type) (((type) & 0x7) << 5)
	#define FMC_ECC_TYPE_MASK GENMASK(7, 5)
	#define SPI_NOR_ADDR_MODE_MASK BIT_MASK(10)
	#define SPI_NOR_ADDR_MODE_3BYTES (0x0 << 10)
	#define SPI_NOR_ADDR_MODE_4BYTES (0x1 << 10)
	#define FMC_GLOBAL_CFG 0x04
	#define FMC_GLOBAL_CFG_WP_ENABLE BIT(6)
	#define FMC_SPI_TIMING_CFG 0x08
	#define TIMING_CFG_TCSH(nr) (((nr) & 0xf) << 8)
	#define TIMING_CFG_TCSS(nr) (((nr) & 0xf) << 4)
	#define TIMING_CFG_TSHSL(nr) ((nr) & 0xf)
	#define CS_HOLD_TIME 0x6
	#define CS_SETUP_TIME 0x6
	#define CS_DESELECT_TIME 0xf
	#define FMC_INT 0x18
	#define FMC_INT_OP_DONE BIT(0)
	#define FMC_INT_CLR 0x20
	#define FMC_CMD 0x24
	#define FMC_CMD_CMD1(cmd) ((cmd) & 0xff)
	#define FMC_ADDRL 0x2c
	#define FMC_OP_CFG 0x30
	#define OP_CFG_FM_CS(cs) ((cs) << 11)
	#define OP_CFG_MEM_IF_TYPE(type) (((type) & 0x7) << 7)
	#define OP_CFG_ADDR_NUM(addr) (((addr) & 0x7) << 4)
	#define OP_CFG_DUMMY_NUM(dummy) ((dummy) & 0xf)
	#define FMC_DATA_NUM 0x38
	#define FMC_DATA_NUM_CNT(cnt) ((cnt) & GENMASK(13, 0))
	#define FMC_OP 0x3c
	#define FMC_OP_DUMMY_EN BIT(8)
	#define FMC_OP_CMD1_EN BIT(7)
	#define FMC_OP_ADDR_EN BIT(6)
	#define FMC_OP_WRITE_DATA_EN BIT(5)
	#define FMC_OP_READ_DATA_EN BIT(2)
	#define FMC_OP_READ_STATUS_EN BIT(1)
	#define FMC_OP_REG_OP_START BIT(0)
	#define FMC_DMA_LEN 0x40
	#define FMC_DMA_LEN_SET(len) ((len) & GENMASK(27, 0))
	#define FMC_DMA_SADDR_D0 0x4c
	#define HIFMC_DMA_MAX_LEN (4096)
	#define HIFMC_DMA_MASK (HIFMC_DMA_MAX_LEN - 1)
	#define FMC_OP_DMA 0x68
	#define OP_CTRL_RD_OPCODE(code) (((code) & 0xff) << 16)
	#define OP_CTRL_WR_OPCODE(code) (((code) & 0xff) << 8)
	#define OP_CTRL_RW_OP(op) ((op) << 1)
	#define OP_CTRL_DMA_OP_READY BIT(0)
	#define FMC_OP_READ 0x0
	#define FMC_OP_WRITE 0x1
	#define FMC_WAIT_TIMEOUT 1000000

	enum hifmc_iftype {
	IF_TYPE_STD,
	IF_TYPE_DUAL,
	IF_TYPE_DIO,
	IF_TYPE_QUAD,
	IF_TYPE_QIO,
	};

	struct hifmc_priv {
	u32 chipselect;
	u32 clkrate;
	struct hifmc_host *host;
	};

	#define HIFMC_MAX_CHIP_NUM 2
	struct hifmc_host {
	struct device *dev;
	struct mutex lock;

	void __iomem *regbase;
	void __iomem *iobase;
	struct clk *clk;
	void *buffer;
	dma_addr_t dma_buffer;

	struct spi_nor *nor[HIFMC_MAX_CHIP_NUM];
	u32 num_chip;
	};

	static inline int hisi_spi_nor_wait_op_finish(struct hifmc_host *host)
	{
	u32 reg;

	return readl_poll_timeout(host->regbase + FMC_INT, reg,
	(reg & FMC_INT_OP_DONE), 0, FMC_WAIT_TIMEOUT);
	}

	static int hisi_spi_nor_get_if_type(enum spi_nor_protocol proto)
	{
	enum hifmc_iftype if_type;

	switch (proto) {
	case SNOR_PROTO_1_1_2:
	if_type = IF_TYPE_DUAL;
	break;
	case SNOR_PROTO_1_2_2:
	if_type = IF_TYPE_DIO;
	break;
	case SNOR_PROTO_1_1_4:
	if_type = IF_TYPE_QUAD;
	break;
	case SNOR_PROTO_1_4_4:
	if_type = IF_TYPE_QIO;
	break;
	case SNOR_PROTO_1_1_1:
	default:
	if_type = IF_TYPE_STD;
	break;
	}

	return if_type;
	}

	static void hisi_spi_nor_init(struct hifmc_host *host)
	{
	u32 reg;

	reg = TIMING_CFG_TCSH(CS_HOLD_TIME)
	\| TIMING_CFG_TCSS(CS_SETUP_TIME)
	\| TIMING_CFG_TSHSL(CS_DESELECT_TIME);
	writel(reg, host->regbase + FMC_SPI_TIMING_CFG);
	}

	static int hisi_spi_nor_prep(struct spi_nor *nor, enum spi_nor_ops ops)
	{
	struct hifmc_priv *priv = nor->priv;
	struct hifmc_host *host = priv->host;
	int ret;

	mutex_lock(&host->lock);

	ret = clk_set_rate(host->clk, priv->clkrate);
	if (ret)
	goto out;

	ret = clk_prepare_enable(host->clk);
	if (ret)
	goto out;

	return 0;

	out:
	mutex_unlock(&host->lock);
	return ret;
	}

	static void hisi_spi_nor_unprep(struct spi_nor *nor, enum spi_nor_ops ops)
	{
	struct hifmc_priv *priv = nor->priv;
	struct hifmc_host *host = priv->host;

	clk_disable_unprepare(host->clk);
	mutex_unlock(&host->lock);
	}

	static int hisi_spi_nor_op_reg(struct spi_nor *nor,
	u8 opcode, int len, u8 optype)
	{
	struct hifmc_priv *priv = nor->priv;
	struct hifmc_host *host = priv->host;
	u32 reg;

	reg = FMC_CMD_CMD1(opcode);
	writel(reg, host->regbase + FMC_CMD);

	reg = FMC_DATA_NUM_CNT(len);
	writel(reg, host->regbase + FMC_DATA_NUM);

	reg = OP_CFG_FM_CS(priv->chipselect);
	writel(reg, host->regbase + FMC_OP_CFG);

	writel(0xff, host->regbase + FMC_INT_CLR);
	reg = FMC_OP_CMD1_EN \| FMC_OP_REG_OP_START \| optype;
	writel(reg, host->regbase + FMC_OP);

	return hisi_spi_nor_wait_op_finish(host);
	}

	static int hisi_spi_nor_read_reg(struct spi_nor nor, u8 opcode, u8 buf,
	int len)
	{
	struct hifmc_priv *priv = nor->priv;
	struct hifmc_host *host = priv->host;
	int ret;

	ret = hisi_spi_nor_op_reg(nor, opcode, len, FMC_OP_READ_DATA_EN);
	if (ret)
	return ret;

	memcpy_fromio(buf, host->iobase, len);
	return 0;
	}

	static int hisi_spi_nor_write_reg(struct spi_nor *nor, u8 opcode,
	u8 *buf, int len)
	{
	struct hifmc_priv *priv = nor->priv;
	struct hifmc_host *host = priv->host;

	if (len)
	memcpy_toio(host->iobase, buf, len);

	return hisi_spi_nor_op_reg(nor, opcode, len, FMC_OP_WRITE_DATA_EN);
	}

	static int hisi_spi_nor_dma_transfer(struct spi_nor *nor, loff_t start_off,
	dma_addr_t dma_buf, size_t len, u8 op_type)
	{
	struct hifmc_priv *priv = nor->priv;
	struct hifmc_host *host = priv->host;
	u8 if_type = 0;
	u32 reg;

	reg = readl(host->regbase + FMC_CFG);
	reg &= ~(FMC_CFG_OP_MODE_MASK \| SPI_NOR_ADDR_MODE_MASK);
	reg \|= FMC_CFG_OP_MODE_NORMAL;
	reg \|= (nor->addr_width == 4) ? SPI_NOR_ADDR_MODE_4BYTES
	: SPI_NOR_ADDR_MODE_3BYTES;
	writel(reg, host->regbase + FMC_CFG);

	writel(start_off, host->regbase + FMC_ADDRL);
	writel(dma_buf, host->regbase + FMC_DMA_SADDR_D0);
	writel(FMC_DMA_LEN_SET(len), host->regbase + FMC_DMA_LEN);

	reg = OP_CFG_FM_CS(priv->chipselect);
	if (op_type == FMC_OP_READ)
	if_type = hisi_spi_nor_get_if_type(nor->read_proto);
	else
	if_type = hisi_spi_nor_get_if_type(nor->write_proto);
	reg \|= OP_CFG_MEM_IF_TYPE(if_type);
	if (op_type == FMC_OP_READ)
	reg \|= OP_CFG_DUMMY_NUM(nor->read_dummy >> 3);
	writel(reg, host->regbase + FMC_OP_CFG);

	writel(0xff, host->regbase + FMC_INT_CLR);
	reg = OP_CTRL_RW_OP(op_type) \| OP_CTRL_DMA_OP_READY;
	reg \|= (op_type == FMC_OP_READ)
	? OP_CTRL_RD_OPCODE(nor->read_opcode)
	: OP_CTRL_WR_OPCODE(nor->program_opcode);
	writel(reg, host->regbase + FMC_OP_DMA);

	return hisi_spi_nor_wait_op_finish(host);
	}

	static ssize_t hisi_spi_nor_read(struct spi_nor *nor, loff_t from, size_t len,
	u_char *read_buf)
	{
	struct hifmc_priv *priv = nor->priv;
	struct hifmc_host *host = priv->host;
	size_t offset;
	int ret;

	for (offset = 0; offset < len; offset += HIFMC_DMA_MAX_LEN) {
	size_t trans = min_t(size_t, HIFMC_DMA_MAX_LEN, len - offset);

	ret = hisi_spi_nor_dma_transfer(nor,
	from + offset, host->dma_buffer, trans, FMC_OP_READ);
	if (ret) {
	dev_warn(nor->dev, "DMA read timeout\n");
	return ret;
	}
	memcpy(read_buf + offset, host->buffer, trans);
	}

	return len;
	}

	static ssize_t hisi_spi_nor_write(struct spi_nor *nor, loff_t to,
	size_t len, const u_char *write_buf)
	{
	struct hifmc_priv *priv = nor->priv;
	struct hifmc_host *host = priv->host;
	size_t offset;
	int ret;

	for (offset = 0; offset < len; offset += HIFMC_DMA_MAX_LEN) {
	size_t trans = min_t(size_t, HIFMC_DMA_MAX_LEN, len - offset);

	memcpy(host->buffer, write_buf + offset, trans);
	ret = hisi_spi_nor_dma_transfer(nor,
	to + offset, host->dma_buffer, trans, FMC_OP_WRITE);
	if (ret) {
	dev_warn(nor->dev, "DMA write timeout\n");
	return ret;
	}
	}

	return len;
	}

	/**
	* Get spi flash device information and register it as a mtd device.
	*/
	static int hisi_spi_nor_register(struct device_node *np,
	struct hifmc_host *host)
	{
	const struct spi_nor_hwcaps hwcaps = {
	.mask = SNOR_HWCAPS_READ \|
	SNOR_HWCAPS_READ_FAST \|
	SNOR_HWCAPS_READ_1_1_2 \|
	SNOR_HWCAPS_READ_1_1_4 \|
	SNOR_HWCAPS_PP,
	};
	struct device *dev = host->dev;
	struct spi_nor *nor;
	struct hifmc_priv *priv;
	struct mtd_info *mtd;
	int ret;

	nor = devm_kzalloc(dev, sizeof(*nor), GFP_KERNEL);
	if (!nor)
	return -ENOMEM;

	nor->dev = dev;
	spi_nor_set_flash_node(nor, np);

	priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
	if (!priv)
	return -ENOMEM;

	ret = of_property_read_u32(np, "reg", &priv->chipselect);
	if (ret) {
	dev_err(dev, "There's no reg property for %pOF\n",
	np);
	return ret;
	}

	ret = of_property_read_u32(np, "spi-max-frequency",
	&priv->clkrate);
	if (ret) {
	dev_err(dev, "There's no spi-max-frequency property for %pOF\n",
	np);
	return ret;
	}
	priv->host = host;
	nor->priv = priv;

	nor->prepare = hisi_spi_nor_prep;
	nor->unprepare = hisi_spi_nor_unprep;
	nor->read_reg = hisi_spi_nor_read_reg;
	nor->write_reg = hisi_spi_nor_write_reg;
	nor->read = hisi_spi_nor_read;
	nor->write = hisi_spi_nor_write;
	nor->erase = NULL;
	ret = spi_nor_scan(nor, NULL, &hwcaps);
	if (ret)
	return ret;

	mtd = &nor->mtd;
	mtd->name = np->name;
	ret = mtd_device_register(mtd, NULL, 0);
	if (ret)
	return ret;

	host->nor[host->num_chip] = nor;
	host->num_chip++;
	return 0;
	}

	static void hisi_spi_nor_unregister_all(struct hifmc_host *host)
	{
	int i;

	for (i = 0; i < host->num_chip; i++)
	mtd_device_unregister(&host->nor[i]->mtd);
	}

	static int hisi_spi_nor_register_all(struct hifmc_host *host)
	{
	struct device *dev = host->dev;
	struct device_node *np;
	int ret;

	for_each_available_child_of_node(dev->of_node, np) {
	ret = hisi_spi_nor_register(np, host);
	if (ret)
	goto fail;

	if (host->num_chip == HIFMC_MAX_CHIP_NUM) {
	dev_warn(dev, "Flash device number exceeds the maximum chipselect number\n");
	of_node_put(np);
	break;
	}
	}

	return 0;

	fail:
	hisi_spi_nor_unregister_all(host);
	return ret;
	}

	static int hisi_spi_nor_probe(struct platform_device *pdev)
	{
	struct device *dev = &pdev->dev;
	struct resource *res;
	struct hifmc_host *host;
	int ret;

	host = devm_kzalloc(dev, sizeof(*host), GFP_KERNEL);
	if (!host)
	return -ENOMEM;

	platform_set_drvdata(pdev, host);
	host->dev = dev;

	res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "control");
	host->regbase = devm_ioremap_resource(dev, res);
	if (IS_ERR(host->regbase))
	return PTR_ERR(host->regbase);

	res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "memory");
	host->iobase = devm_ioremap_resource(dev, res);
	if (IS_ERR(host->iobase))
	return PTR_ERR(host->iobase);

	host->clk = devm_clk_get(dev, NULL);
	if (IS_ERR(host->clk))
	return PTR_ERR(host->clk);

	ret = dma_set_mask_and_coherent(dev, DMA_BIT_MASK(32));
	if (ret) {
	dev_warn(dev, "Unable to set dma mask\n");
	return ret;
	}

	host->buffer = dmam_alloc_coherent(dev, HIFMC_DMA_MAX_LEN,
	&host->dma_buffer, GFP_KERNEL);
	if (!host->buffer)
	return -ENOMEM;

	ret = clk_prepare_enable(host->clk);
	if (ret)
	return ret;

	mutex_init(&host->lock);
	hisi_spi_nor_init(host);
	ret = hisi_spi_nor_register_all(host);
	if (ret)
	mutex_destroy(&host->lock);

	clk_disable_unprepare(host->clk);
	return ret;
	}

	static int hisi_spi_nor_remove(struct platform_device *pdev)
	{
	struct hifmc_host *host = platform_get_drvdata(pdev);

	hisi_spi_nor_unregister_all(host);
	mutex_destroy(&host->lock);
	clk_disable_unprepare(host->clk);
	return 0;
	}

	static const struct of_device_id hisi_spi_nor_dt_ids[] = {
	{ .compatible = "hisilicon,fmc-spi-nor"},
	{ /* sentinel */ }
	};
	MODULE_DEVICE_TABLE(of, hisi_spi_nor_dt_ids);

	static struct platform_driver hisi_spi_nor_driver = {
	.driver = {
	.name = "hisi-sfc",
	.of_match_table = hisi_spi_nor_dt_ids,
	},
	.probe = hisi_spi_nor_probe,
	.remove = hisi_spi_nor_remove,
	};
	module_platform_driver(hisi_spi_nor_driver);

	MODULE_LICENSE("GPL v2");
	MODULE_DESCRIPTION("HiSilicon SPI Nor Flash Controller Driver");