2018年10月12日 | Tiny210驱动之NAND_FLASH驱动程序

tiny_nand.c驱动源码：

#include "linux/module.h"

#include "linux/types.h"

#include "linux/init.h"

#include "linux/kernel.h"

#include "linux/string.h"

#include "linux/ioport.h"

#include "linux/platform_device.h"

#include "linux/delay.h"

#include "linux/err.h"

#include "linux/slab.h"

#include "linux/clk.h"

#include "linux/cpufreq.h"

#include "linux/mtd/mtd.h"

#include "linux/mtd/nand.h"

#include "linux/mtd/nand_ecc.h"

#include "linux/mtd/partitions.h"

#include "asm/io.h"

#include "plat/regs-nand.h"

#include "plat/nand.h"

static unsigned long *clk_gate_ip1;

static unsigned long *clk_gate_block;

static unsigned long *mp0_3con;

static struct mtd_partition tiny_nand_part[] = {

    [0] = {

        .name    = "bootloader",

        .size    = SZ_4M,

        .offset    = 0,

    },

    [1] = {

        .name    = "kernel",

        .size    = SZ_8M,

        .offset    = MTDPART_OFS_APPEND,

    },

    [2] = {

        .name    = "root",

        .size    = MTDPART_SIZ_FULL,

        .offset    = MTDPART_OFS_APPEND,

    },

};

struct nand_regs {

    unsigned long nfconf;

    unsigned long nfcont;

    unsigned long nfcmmd;

    unsigned long nfaddr;

    unsigned long nfdata;

    unsigned long nfmeccd0;

    unsigned long nfmeccd1;

    unsigned long nfseccd;

    unsigned long nfsblk;

    unsigned long nfeblk;

    unsigned long nfstat;

    unsigned long nfeccerr0;

    unsigned long nfeccerr1;

};

static struct nand_regs *nand_regs;

static struct nand_chip *tiny_nand_chip;

static struct mtd_info *tiny_nand_mtd;

static void tiny_nand_select_chip(struct mtd_info *mtd, int chipnr)

{

    if(chipnr == -1)

    {

        //取消选择

        nand_regs->nfcont |= (1<<1);

    }

    else

    {

        //选中芯片

        nand_regs->nfcont &= ~(1<<1);

    }

}

static void tiny_nand_cmd_ctrl(struct mtd_info *mtd, int dat,unsigned int ctrl)

{

    if (ctrl & NAND_CLE)

    {

        //发命令

        nand_regs->nfcmmd = dat;

    }

    else

    {

        //发地址

        nand_regs->nfaddr = dat;

    }

}

static int tiny_nand_dev_ready(struct mtd_info *mtd)

{

    //等待命令的操作完成

    return (nand_regs->nfstat & (1<<0));

}

static int tiny_nand_init(void)

{

    //1.分配一个nand_chip结构体

    tiny_nand_chip = kzalloc(sizeof(struct nand_chip),GFP_KERNEL);

    nand_regs = ioremap(0xB0E00000,sizeof(struct nand_regs));

    mp0_3con         = ioremap(0xE0200320,4);

    clk_gate_ip1     = ioremap(0xE0100464,4);

    clk_gate_block = ioremap(0xE0100480,4);

    //2.设置

    //

    // 初始化nand_chip结构体中的函数指针

    // 提供选中芯片，发命令，发地址，读数据，写数据，等待等操作

    tiny_nand_chip->select_chip    = tiny_nand_select_chip;

    tiny_nand_chip->cmd_ctrl        = tiny_nand_cmd_ctrl;

    tiny_nand_chip->IO_ADDR_R   = &nand_regs->nfdata;

    tiny_nand_chip->IO_ADDR_W  = &nand_regs->nfdata;

    tiny_nand_chip->dev_ready     = tiny_nand_dev_ready;

    tiny_nand_chip->ecc.mode      = NAND_ECC_SOFT;

    //tiny_nand_chip->ecc.mode      = NAND_ECC_NONE;

    //3.硬件相关

    //使能时钟

    *clk_gate_ip1     = 0xffffffff;

    *clk_gate_block = 0xffffffff;

    // 设置相应GPIO管脚用于Nand 

    *mp0_3con = 0x22222222;

    // 设置时序 

#define TWRPH1    1

#define TWRPH0    1

#define TACLS        1

    nand_regs->nfconf |= (TACLS<<12) | (TWRPH0<<8) | (TWRPH1<<4);

    // AddrCycle[1]:1 = 发送地址需要5个周期

    nand_regs->nfconf |= 1<<1;

    // MODE[0]:1     = 使能Nand Flash控制器

    // Reg_nCE0[1]:1 = 取消片选

    nand_regs->nfcont |= (1<<1)|(1<<0);

    //4.使用

    tiny_nand_mtd = kzalloc(sizeof(struct mtd_info), GFP_KERNEL);

    tiny_nand_mtd->owner = THIS_MODULE;

    tiny_nand_mtd->priv = tiny_nand_chip;

    nand_scan(tiny_nand_mtd, 1);

    //5.添加分区

    add_mtd_partitions(tiny_nand_mtd, tiny_nand_part, 3);

    return 0;

}

static void tiny_nand_exit(void)

{

    del_mtd_partitions(tiny_nand_mtd);

    kfree(tiny_nand_mtd);

    iounmap(nand_regs);

    kfree(tiny_nand_chip);

}

module_init(tiny_nand_init);

module_exit(tiny_nand_exit);

MODULE_LICENSE("GPL");