本篇目标：在linux-4.9.2的源码中，配置nand flash的分区表。

4.1 修改mach-mini2440.c

切换回之前的putty窗口，用vim打开mach-mini2440.c文件，在第148行之后添加如下代码：（红色部分）

        .lpcsel         = ((0xCE6) & ~7) | 1<<4,

};

 

/* NAND parititon from 2.4.18-swl5 */

static struct mtd_partitionmini2440_default_nand_part[] = {

        [0]= {

               .name = "boot",

                .offset = 0,

               .size = 0x00040000, //256K

        },

        [1]= {

               .name = "param",

               .offset = 0x00040000,

               .size = 0x00020000,

        },

        [2]= {

               .name = "kernel", //;内核所在的分区，大小为5M

               .offset = 0x00060000,

               .size = 0x00500000,

        },

        [3]= {

               .name = "rootfs", //;文件系统分区，友善之臂主要用来存放yaffs2文件系统内容，对应/dev/mtdblock3

               .offset = 0x00560000,

               .size = 100 * 1024 * 1024, //100*1024*1024，100MB

        },

        [4]= {

               .name = "nand", //;此区域代表了整片的nand flash，主要是预留使用，比如以后可以通过应用程序访问读取/dev/mtdblock4就能实现备份整片nand flash 了。

               .offset = 0x00000000,

                .size = 256 * 1024 * 1024, //256*1024*1024，256MB

        }

};

/*;这里是开发板的nand flash设置表，因为板子上只有一片，因此也就只有一个表*/

static struct s3c2410_nand_setmini2440_nand_sets[] = {

        [0]= {

               .name  = "NAND",

                .nr_chips = 1,

               .nr_partitions = ARRAY_SIZE(mini2440_default_nand_part),

               .nr_chips = 1,

               .nr_partitions = ARRAY_SIZE(mini2440_default_nand_part),

                         .partitions =mini2440_default_nand_part,

        },

};

/* choose a set of timings which should suit most512Mbit

 *  * chips and beyond.

 *  */

static struct s3c2410_platform_nandmini2440_nand_info = {

       .tacls  = 20,

       .twrph0  = 60,

       .twrph1  = 20,

       .nr_sets = ARRAY_SIZE(mini2440_nand_sets),

       .sets  = mini2440_nand_sets,

       .ignore_unset_ecc = 1,

};

 

4.2 把nand flash 设备注册到系统中

static struct platform_device *mini2440_devices[] __initdata = {

        &s3c_device_ohci,

        &s3c_device_lcd,

        &s3c_device_wdt,

        &s3c_device_i2c0,

        &s3c_device_iis,

        &s3c_device_nand,

};

 

4.3加入编译头文件

在上面的文件中定位到47行附近，加入一下头文件：

#include <linux/mtd/mtd.h>

#include <linux/mtd/nand.h>

#include <linux/mtd/nand_ecc.h>

#include <linux/mtd/partitions.h>

#include<linux/platform_data/mtd-nand-s3c2410.h>

 

4.4 传入mini2440_nand_info结构体初始化参数

定位到233行附近，修改如下：

 

static void __init mini2440_machine_init(void)

{

       s3c24xx_fb_set_platdata(&mini2440_fb_info);

       s3c_i2c0_set_platdata(NULL);

        s3c_device_nand.dev.platform_data = &mini2440_nand_info;

       platform_add_devices(mini2440_devices, ARRAY_SIZE(mini2440_devices));

//      smdk_machine_init();

}

然后保存。

 

4.5 修改配置

切换到另一个编译的putty窗口

root@ubuntu:~/linux-4.9.2# make menuconfig

 

在配置菜单->DeviceDrivers ->Memory Technology Devices (MTD)，如图

 

按空格键取消选择，然后选“Exit”退出，最后出现保存提示时选择“Yes”保存。然后在终端中执行：

root@ubuntu:~/linux-4.9.2# make -j8

root@ubuntu:~/linux-4.9.2# ./mkuImage.sh

 

4.6 重启开发板

看到串口打印中的nand flash分区情况，移植nand flash成功。

nand: 256 MiB, SLC, erase size: 128 KiB, page size: 2048, OOB size:64

Scanning device for bad blocks

Bad eraseblock 1620 at 0x00000ca80000

Bad eraseblock 1935 at 0x00000f1e0000

Creating 5 MTD partitions on "NAND":

0x000000000000-0x000000040000 : "boot"

0x000000040000-0x000000060000 : "param"

0x000000060000-0x000000560000 : "kernel"

0x000000560000-0x000006960000 : "rootfs"

0x000000000000-0x000010000000 : "nand"

ohci_hcd: USB 1.1 'Open' Host Controller (OHCI) Driver

ohci-s3c2410:OHCI S3C2410 driver