Commit 3ce351b5 authored by Bayi Cheng's avatar Bayi Cheng Committed by Brian Norris
Browse files

mtd: mtk-nor: new Mediatek serial flash controller driver 



Add spi nor flash driver for mediatek controller

Signed-off-by: default avatarBayi Cheng <bayi.cheng@mediatek.com>
Signed-off-by: default avatarBrian Norris <computersforpeace@gmail.com>
parent 72eaec21

drivers/mtd/spi-nor/Kconfig

+7 −0
Original line number Diff line number Diff line
@@ -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

drivers/mtd/spi-nor/Makefile

+1 −0
Original line number Diff line number Diff line 
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

drivers/mtd/spi-nor/mtk-quadspi.c

0 → 100644
+486 −0
Original line number Diff line number Diff line 
/*

 * Copyright (c) 2015 MediaTek Inc.

 * Author: Bayi Cheng <bayi.cheng@mediatek.com>

 *

 * 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");