Re: [PATCH v2 2/3] mtd: mtk-nor: mtk serial flash controller driver

From: Huang Shijie
Date: Fri Sep 18 2015 - 03:27:41 EST

On Fri, Sep 18, 2015 at 02:58:52PM +0800, Bayi Cheng wrote:
> 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 | 483 ++++++++++++++++++++++++++++++++++++++
> 3 files changed, 491 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 89bf4c1..f433890 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 "Support SPI flash Controller MTD_MT81xx_NOR"
> + help
> + This enables access to SPI Nor flash, using MTD_MT81XX_NOR controller.
> + This controller does nor 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..138cfea 100644
> --- a/drivers/mtd/spi-nor/Makefile
> +++ b/drivers/mtd/spi-nor/Makefile
> @@ -1,3 +1,4 @@
> +obj-$(CONFIG_MTD_MT81xx_NOR) += mtk_quadspi.o
> obj-$(CONFIG_MTD_SPI_NOR) += spi-nor.o
> obj-$(CONFIG_SPI_FSL_QUADSPI) += fsl-quadspi.o
> obj-$(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..f60560e
> --- /dev/null
> +++ b/drivers/mtd/spi-nor/mtk_quadspi.c
> @@ -0,0 +1,483 @@
> +/*
> + * 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/of_gpio.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_FLHCFG_REG 0x84
> +#define MTK_NOR_PP_DATA_REG 0x98
> +#define MTK_NOR_PREBUF_STUS_REG 0x9c
> +#define MTK_NOR_INTRSTUS_REG 0xa8
> +#define MTK_NOR_INTREN_REG 0xac
> +#define MTK_NOR_TIME_REG 0x94
> +#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_DELSEL0_REG 0xa0
> +#define MTK_NOR_DELSEL1_REG 0xa4
> +#define MTK_NOR_DELSEL2_REG 0xd0
> +#define MTK_NOR_DELSEL3_REG 0xd4
> +#define MTK_NOR_DELSEL4_REG 0xd8
> +#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
> +/* 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_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
> +#define MAX_FLASHCOUNT 1
> +#define SFLASHHWNAME_LEN 12
> +#define SFLASH_MAX_DMA_SIZE (1024 * 8)
> +
> +#define LOCAL_BUF_SIZE (SFLASH_MAX_DMA_SIZE * 20)
> +
> +struct mt8173_nor {
> + struct mtd_info mtd;
> + 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(SPINOR_OP_READ_FAST, 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(SPINOR_OP_READ_1_1_2, 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(SPINOR_OP_READ_1_1_4, mt8173_nor->base +
> + MTK_NOR_PRGDATA3_REG);
> + writeb(MTK_NOR_QUAD_READ_EN, mt8173_nor->base +
> + MTK_NOR_DUAL_REG);
> + break;
> + default:
> + writeb(SPINOR_OP_READ, mt8173_nor->base +
> + MTK_NOR_PRGDATA3_REG);
> + 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_set_cmd(struct mt8173_nor *mt8173_nor, int addr, int len,
> + int op)
> +{
> + writeb(op, mt8173_nor->base + MTK_NOR_PRGDATA5_REG);
> + /* send the address to nor flash
> + * MTK_NOR_PRGDATA5_REG is shifted first
> + * MTK_NOR_PRGDATA0_REG is shifted last
> + */
> + writeb(((addr >> 16) & 0xff), mt8173_nor->base + MTK_NOR_PRGDATA4_REG);
> + writeb(((addr >> 8) & 0xff), mt8173_nor->base + MTK_NOR_PRGDATA3_REG);
> + writeb((addr & 0xff), mt8173_nor->base + MTK_NOR_PRGDATA2_REG);
Why not use some macros to wrap the hardcode such as:
(addr >> 16) & 0xff.

thanks
Huang Shijie

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