mtd: spi-nor: add hisilicon spi-nor flash controller driver

Add hisilicon spi-nor flash controller driver
Signed-off-by: NBinquan Peng <pengbinquan@hisilicon.com>
Signed-off-by: NJiancheng Xue <xuejiancheng@hisilicon.com>
Acked-by: NRob Herring <robh@kernel.org>
Reviewed-by: NEzequiel Garcia <ezequiel@vanguardiasur.com.ar>
Reviewed-by: NJagan Teki <jteki@openedev.com>
Reviewed-by: NCyrille Pitchen <cyrille.pitchen@atmel.com>
Signed-off-by: NBrian Norris <computersforpeace@gmail.com>

Documentation/devicetree/bindings/mtd/hisilicon,fmc-spi-nor.txt

+HiSilicon SPI-NOR Flash Controller
+
+Required properties:
+- compatible : Should be "hisilicon,fmc-spi-nor" and one of the following strings:
+		"hisilicon,hi3519-spi-nor"
+- address-cells : Should be 1.
+- size-cells : Should be 0.
+- reg : Offset and length of the register set for the controller device.
+- reg-names : Must include the following two entries: "control", "memory".
+- clocks : handle to spi-nor flash controller clock.
+
+Example:
+spi-nor-controller@10000000 {
+	compatible = "hisilicon,hi3519-spi-nor", "hisilicon,fmc-spi-nor";
+	#address-cells = <1>;
+	#size-cells = <0>;
+	reg = <0x10000000 0x1000>, <0x14000000 0x1000000>;
+	reg-names = "control", "memory";
+	clocks = <&clock HI3519_FMC_CLK>;
+	spi-nor@0 {
+		compatible = "jedec,spi-nor";
+		reg = <0>;
+	};
+};

drivers/mtd/spi-nor/Kconfig

@@ -38,6 +38,13 @@ config SPI_FSL_QUADSPI
 	  This controller does not support generic SPI. It only supports
 	  SPI NOR.
 
+config SPI_HISI_SFC
+	tristate "Hisilicon SPI-NOR Flash Controller(SFC)"
+	depends on ARCH_HISI || COMPILE_TEST
+	depends on HAS_IOMEM && HAS_DMA
+	help
+	  This enables support for hisilicon SPI-NOR flash controller.
+
 config SPI_NXP_SPIFI
 	tristate "NXP SPI Flash Interface (SPIFI)"
 	depends on OF && (ARCH_LPC18XX || COMPILE_TEST)

drivers/mtd/spi-nor/Makefile

 obj-$(CONFIG_MTD_SPI_NOR)	+= spi-nor.o
 obj-$(CONFIG_SPI_FSL_QUADSPI)	+= fsl-quadspi.o
+obj-$(CONFIG_SPI_HISI_SFC)	+= hisi-sfc.o
 obj-$(CONFIG_MTD_MT81xx_NOR)    += mtk-quadspi.o
 obj-$(CONFIG_SPI_NXP_SPIFI)	+= nxp-spifi.o

drivers/mtd/spi-nor/hisi-sfc.c

+/*
+ * HiSilicon SPI Nor Flash Controller Driver
+ *
+ * Copyright (c) 2015-2016 HiSilicon Technologies Co., Ltd.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+#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 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 get_if_type(enum read_mode flash_read)
+{
+	enum hifmc_iftype if_type;
+
+	switch (flash_read) {
+	case SPI_NOR_DUAL:
+		if_type = IF_TYPE_DUAL;
+		break;
+	case SPI_NOR_QUAD:
+		if_type = IF_TYPE_QUAD;
+		break;
+	case SPI_NOR_NORMAL:
+	case SPI_NOR_FAST:
+	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 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_type = get_if_type(nor->flash_read);
+	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 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)
+{
+	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 %s\n",
+			np->full_name);
+		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 %s\n",
+			np->full_name);
+		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, SPI_NOR_QUAD);
+	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");
+			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;
+
+	mutex_init(&host->lock);
+	clk_prepare_enable(host->clk);
+	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");