[PATCH v8 1/2] mtd: mtk-nor: mtk serial flash controller driver

From: Bayi Cheng
Date: Tue Nov 17 2015 - 22:37:43 EST


add spi nor flash driver for mediatek controller

Signed-off-by: Bayi Cheng <bayi.cheng@xxxxxxxxxxxx>
---
drivers/mtd/spi-nor/Kconfig | 7 +
drivers/mtd/spi-nor/Makefile | 1 +
drivers/mtd/spi-nor/mtk-quadspi.c | 486 ++++++++++++++++++++++++++++++++++++++
3 files changed, 494 insertions(+)
create mode 100644 drivers/mtd/spi-nor/mtk-quadspi.c

diff --git a/drivers/mtd/spi-nor/Kconfig b/drivers/mtd/spi-nor/Kconfig
index 2fe2a7e..0dc9275 100644
--- a/drivers/mtd/spi-nor/Kconfig
+++ b/drivers/mtd/spi-nor/Kconfig
@@ -7,6 +7,13 @@ menuconfig MTD_SPI_NOR

if MTD_SPI_NOR

+config MTD_MT81xx_NOR
+ tristate "Mediatek MT81xx SPI NOR flash controller"
+ help
+ This enables access to SPI NOR flash, using MT81xx SPI NOR flash
+ controller. This controller does not support generic SPI BUS, it only
+ supports SPI NOR Flash.
+
config MTD_SPI_NOR_USE_4K_SECTORS
bool "Use small 4096 B erase sectors"
default y
diff --git a/drivers/mtd/spi-nor/Makefile b/drivers/mtd/spi-nor/Makefile
index e53333e..0bf3a7f8 100644
--- a/drivers/mtd/spi-nor/Makefile
+++ b/drivers/mtd/spi-nor/Makefile
@@ -1,3 +1,4 @@
obj-$(CONFIG_MTD_SPI_NOR) += spi-nor.o
obj-$(CONFIG_SPI_FSL_QUADSPI) += fsl-quadspi.o
+obj-$(CONFIG_MTD_MT81xx_NOR) += mtk-quadspi.o
obj-$(CONFIG_SPI_NXP_SPIFI) += nxp-spifi.o
diff --git a/drivers/mtd/spi-nor/mtk-quadspi.c b/drivers/mtd/spi-nor/mtk-quadspi.c
new file mode 100644
index 0000000..7723ac7
--- /dev/null
+++ b/drivers/mtd/spi-nor/mtk-quadspi.c
@@ -0,0 +1,486 @@
+/*
+ * Copyright (c) 2015 MediaTek Inc.
+ * Author: Bayi Cheng <bayi.cheng@xxxxxxxxxxxx>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * 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.
+ */
+
+#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/mtd/mtd.h>
+#include <linux/mutex.h>
+#include <linux/of.h>
+#include <linux/of_device.h>
+#include <linux/pinctrl/consumer.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
+
+/* 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 mt8173_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 mt8173_nor_set_read_mode(struct mt8173_nor *mt8173_nor)
+{
+ struct spi_nor *nor = &mt8173_nor->nor;
+
+ switch (nor->flash_read) {
+ case SPI_NOR_FAST:
+ writeb(nor->read_opcode, mt8173_nor->base +
+ MTK_NOR_PRGDATA3_REG);
+ writeb(MTK_NOR_FAST_READ, mt8173_nor->base +
+ MTK_NOR_CFG1_REG);
+ break;
+ case SPI_NOR_DUAL:
+ writeb(nor->read_opcode, mt8173_nor->base +
+ MTK_NOR_PRGDATA3_REG);
+ writeb(MTK_NOR_DUAL_READ_EN, mt8173_nor->base +
+ MTK_NOR_DUAL_REG);
+ break;
+ case SPI_NOR_QUAD:
+ writeb(nor->read_opcode, mt8173_nor->base +
+ MTK_NOR_PRGDATA4_REG);
+ writeb(MTK_NOR_QUAD_READ_EN, mt8173_nor->base +
+ MTK_NOR_DUAL_REG);
+ break;
+ default:
+ writeb(MTK_NOR_DUAL_DISABLE, mt8173_nor->base +
+ MTK_NOR_DUAL_REG);
+ break;
+ }
+}
+
+static int mt8173_nor_execute_cmd(struct mt8173_nor *mt8173_nor, u8 cmdval)
+{
+ int reg;
+ u8 val = cmdval & 0x1f;
+
+ writeb(cmdval, mt8173_nor->base + MTK_NOR_CMD_REG);
+ return readl_poll_timeout(mt8173_nor->base + MTK_NOR_CMD_REG, reg,
+ !(reg & val), 100, 10000);
+}
+
+static int mt8173_nor_do_tx_rx(struct mt8173_nor *mt8173_nor, u8 op,
+ u8 *tx, int txlen, u8 *rx, int rxlen)
+{
+ int len = 1 + txlen + rxlen;
+ int i, ret, idx;
+
+ if (len > MTK_NOR_MAX_SHIFT)
+ return -EINVAL;
+
+ writeb(len * 8, mt8173_nor->base + MTK_NOR_CNT_REG);
+
+ /* start at PRGDATA5, go down to PRGDATA0 */
+ idx = MTK_NOR_MAX_RX_TX_SHIFT - 1;
+
+ /* opcode */
+ writeb(op, mt8173_nor->base + MTK_NOR_PRG_REG(idx));
+ idx--;
+
+ /* program TX data */
+ for (i = 0; i < txlen; i++, idx--)
+ writeb(tx[i], mt8173_nor->base + MTK_NOR_PRG_REG(idx));
+
+ /* clear out rest of TX registers */
+ while (idx >= 0) {
+ writeb(0, mt8173_nor->base + MTK_NOR_PRG_REG(idx));
+ idx--;
+ }
+
+ ret = mt8173_nor_execute_cmd(mt8173_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(mt8173_nor->base + MTK_NOR_SHREG(idx));
+
+ return 0;
+}
+
+/* Do a WRSR (Write Status Register) command */
+static int mt8173_nor_wr_sr(struct mt8173_nor *mt8173_nor, u8 sr)
+{
+ writeb(sr, mt8173_nor->base + MTK_NOR_PRGDATA5_REG);
+ writeb(8, mt8173_nor->base + MTK_NOR_CNT_REG);
+ return mt8173_nor_execute_cmd(mt8173_nor, MTK_NOR_WRSR_CMD);
+}
+
+static int mt8173_nor_write_buffer_enable(struct mt8173_nor *mt8173_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, mt8173_nor->base + MTK_NOR_CFG2_REG);
+ return readb_poll_timeout(mt8173_nor->base + MTK_NOR_CFG2_REG, reg,
+ 0x01 == (reg & 0x01), 100, 10000);
+}
+
+static int mt8173_nor_write_buffer_disable(struct mt8173_nor *mt8173_nor)
+{
+ u8 reg;
+
+ writel(MTK_NOR_WR_BUF_DISABLE, mt8173_nor->base + MTK_NOR_CFG2_REG);
+ return readb_poll_timeout(mt8173_nor->base + MTK_NOR_CFG2_REG, reg,
+ MTK_NOR_WR_BUF_DISABLE == (reg & 0x1), 100,
+ 10000);
+}
+
+static void mt8173_nor_set_addr(struct mt8173_nor *mt8173_nor, u32 addr)
+{
+ int i;
+
+ for (i = 0; i < 3; i++) {
+ writeb(addr & 0xff, mt8173_nor->base + MTK_NOR_RADR0_REG + i * 4);
+ addr >>= 8;
+ }
+ /* Last register is non-contiguous */
+ writeb(addr & 0xff, mt8173_nor->base + MTK_NOR_RADR3_REG);
+}
+
+static int mt8173_nor_read(struct spi_nor *nor, loff_t from, size_t length,
+ size_t *retlen, u_char *buffer)
+{
+ int i, ret;
+ int addr = (int)from;
+ u8 *buf = (u8 *)buffer;
+ struct mt8173_nor *mt8173_nor = nor->priv;
+
+ /* set mode for fast read mode ,dual mode or quad mode */
+ mt8173_nor_set_read_mode(mt8173_nor);
+ mt8173_nor_set_addr(mt8173_nor, addr);
+
+ for (i = 0; i < length; i++, (*retlen)++) {
+ ret = mt8173_nor_execute_cmd(mt8173_nor, MTK_NOR_PIO_READ_CMD);
+ if (ret < 0)
+ return ret;
+ buf[i] = readb(mt8173_nor->base + MTK_NOR_RDATA_REG);
+ }
+ return 0;
+}
+
+static int mt8173_nor_write_single_byte(struct mt8173_nor *mt8173_nor,
+ int addr, int length, u8 *data)
+{
+ int i, ret;
+
+ mt8173_nor_set_addr(mt8173_nor, addr);
+
+ for (i = 0; i < length; i++) {
+ ret = mt8173_nor_execute_cmd(mt8173_nor, MTK_NOR_PIO_WR_CMD);
+ if (ret < 0)
+ return ret;
+ writeb(*data++, mt8173_nor->base + MTK_NOR_WDATA_REG);
+ }
+ return 0;
+}
+
+static int mt8173_nor_write_buffer(struct mt8173_nor *mt8173_nor, int addr,
+ const u8 *buf)
+{
+ int i, bufidx, data;
+
+ mt8173_nor_set_addr(mt8173_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, mt8173_nor->base + MTK_NOR_PP_DATA_REG);
+ }
+ return mt8173_nor_execute_cmd(mt8173_nor, MTK_NOR_WR_CMD);
+}
+
+static void mt8173_nor_write(struct spi_nor *nor, loff_t to, size_t len,
+ size_t *retlen, const u_char *buf)
+{
+ int ret;
+ struct mt8173_nor *mt8173_nor = nor->priv;
+
+ ret = mt8173_nor_write_buffer_enable(mt8173_nor);
+ if (ret < 0)
+ dev_warn(mt8173_nor->dev, "write buffer enable failed!\n");
+
+ while (len >= SFLASH_WRBUF_SIZE) {
+ ret = mt8173_nor_write_buffer(mt8173_nor, to, buf);
+ if (ret < 0)
+ dev_err(mt8173_nor->dev, "write buffer failed!\n");
+ len -= SFLASH_WRBUF_SIZE;
+ to += SFLASH_WRBUF_SIZE;
+ buf += SFLASH_WRBUF_SIZE;
+ (*retlen) += SFLASH_WRBUF_SIZE;
+ }
+ ret = mt8173_nor_write_buffer_disable(mt8173_nor);
+ if (ret < 0)
+ dev_warn(mt8173_nor->dev, "write buffer disable failed!\n");
+
+ if (len) {
+ ret = mt8173_nor_write_single_byte(mt8173_nor, to, (int)len,
+ (u8 *)buf);
+ if (ret < 0)
+ dev_err(mt8173_nor->dev, "write single byte failed!\n");
+ (*retlen) += len;
+ }
+}
+
+static int mt8173_nor_read_reg(struct spi_nor *nor, u8 opcode, u8 *buf, int len)
+{
+ int ret;
+ struct mt8173_nor *mt8173_nor = nor->priv;
+
+ switch (opcode) {
+ case SPINOR_OP_RDSR:
+ ret = mt8173_nor_execute_cmd(mt8173_nor, MTK_NOR_RDSR_CMD);
+ if (ret < 0)
+ return ret;
+ if (len == 1)
+ *buf = readb(mt8173_nor->base + MTK_NOR_RDSR_REG);
+ else
+ dev_err(mt8173_nor->dev, "len should be 1 for read status!\n");
+ break;
+ default:
+ ret = mt8173_nor_do_tx_rx(mt8173_nor, opcode, NULL, 0, buf, len);
+ break;
+ }
+ return ret;
+}
+
+static int mt8173_nor_write_reg(struct spi_nor *nor, u8 opcode, u8 *buf,
+ int len)
+{
+ int ret;
+ struct mt8173_nor *mt8173_nor = nor->priv;
+
+ switch (opcode) {
+ case SPINOR_OP_WRSR:
+ /* We only handle 1 byte */
+ ret = mt8173_nor_wr_sr(mt8173_nor, *buf);
+ break;
+ default:
+ ret = mt8173_nor_do_tx_rx(mt8173_nor, opcode, buf, len, NULL, 0);
+ if (ret)
+ dev_warn(mt8173_nor->dev, "write reg failure!\n");
+ break;
+ }
+ return ret;
+}
+
+static int __init mtk_nor_init(struct mt8173_nor *mt8173_nor,
+ struct device_node *flash_node)
+{
+ int ret;
+ struct spi_nor *nor;
+
+ /* initialize controller to accept commands */
+ writel(MTK_NOR_ENABLE_SF_CMD, mt8173_nor->base + MTK_NOR_WRPROT_REG);
+
+ nor = &mt8173_nor->nor;
+ nor->dev = mt8173_nor->dev;
+ nor->priv = mt8173_nor;
+ spi_nor_set_flash_node(nor, flash_node);
+
+ /* fill the hooks to spi nor */
+ nor->read = mt8173_nor_read;
+ nor->read_reg = mt8173_nor_read_reg;
+ nor->write = mt8173_nor_write;
+ nor->write_reg = mt8173_nor_write_reg;
+ nor->mtd.owner = THIS_MODULE;
+ nor->mtd.name = "mtk_nor";
+ /* initialized with NULL */
+ ret = spi_nor_scan(nor, NULL, SPI_NOR_DUAL);
+ 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 mt8173_nor *mt8173_nor;
+
+ if (!pdev->dev.of_node) {
+ dev_err(&pdev->dev, "No DT found\n");
+ return -EINVAL;
+ }
+
+ mt8173_nor = devm_kzalloc(&pdev->dev, sizeof(*mt8173_nor), GFP_KERNEL);
+ if (!mt8173_nor)
+ return -ENOMEM;
+ platform_set_drvdata(pdev, mt8173_nor);
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ mt8173_nor->base = devm_ioremap_resource(&pdev->dev, res);
+ if (IS_ERR(mt8173_nor->base))
+ return PTR_ERR(mt8173_nor->base);
+
+ mt8173_nor->spi_clk = devm_clk_get(&pdev->dev, "spi");
+ if (IS_ERR(mt8173_nor->spi_clk))
+ return PTR_ERR(mt8173_nor->spi_clk);
+
+ mt8173_nor->nor_clk = devm_clk_get(&pdev->dev, "sf");
+ if (IS_ERR(mt8173_nor->nor_clk))
+ return PTR_ERR(mt8173_nor->nor_clk);
+
+ mt8173_nor->dev = &pdev->dev;
+ ret = clk_prepare_enable(mt8173_nor->spi_clk);
+ if (ret)
+ return ret;
+
+ ret = clk_prepare_enable(mt8173_nor->nor_clk);
+ if (ret) {
+ clk_disable_unprepare(mt8173_nor->spi_clk);
+ 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(mt8173_nor, flash_np);
+
+nor_free:
+ if (ret) {
+ clk_disable_unprepare(mt8173_nor->spi_clk);
+ clk_disable_unprepare(mt8173_nor->nor_clk);
+ }
+ return ret;
+}
+
+static int mtk_nor_drv_remove(struct platform_device *pdev)
+{
+ struct mt8173_nor *mt8173_nor = platform_get_drvdata(pdev);
+
+ clk_disable_unprepare(mt8173_nor->spi_clk);
+ clk_disable_unprepare(mt8173_nor->nor_clk);
+ return 0;
+}
+
+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",
+ .of_match_table = mtk_nor_of_ids,
+ },
+};
+
+module_platform_driver(mtk_nor_driver);
+MODULE_LICENSE("GPL v2");
+MODULE_DESCRIPTION("MediaTek SPI NOR Flash Driver");
--
1.8.1.1.dirty

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