Linux2.6内核移植NOR FLASH 驱动

一、分区信息

HHARM2410-STUDY开发板使用16bit 8M NOR FLASH,分区信息如下:

0x00000000-0x00040000 : "bootloader"

0x00040000-0x00140000 : "kernel"

0x00140000-0x00540000 : "ramdisk"

0x00540000-0x00740000 : "cramfs"

0x00740000-0x00800000 : "jffs2"

二、添加配置项

1、修改 drivers/mtd/maps/Kconfig文件,添加如下内容:

config MTD_S3C2410

tristate "CFI Flash device mapped on S3C2410"

depends on ARM && MTD_CFI

help

This enables access to the CFI Flash on the Cogent S3C2410 board.

If you have such a board, say 'Y' here.

2、修改 drivers/mtd/maps/Makefile文件,添加如下内容:

obj-$(CONFIG_MTD_S3C2410)+= s3c2410.o

3、复制驱动文件s3c2410.c到drivers/mtd/maps目录下

三、配置编译内核

# make menuconfig

以下内容必选:

Memory Technology Devices(MTD)-->

<*>Memory Technology Device (MTD) support

[*]MTD partitioning support

<*>Direct char device access to MTD devices

<*>Caching block device access to MTD devices

RAM/ROM/Flash chip drivers-->

<*>Detect flash chips by Common Flash Interface (CFI) probe

<*>Support for Inter/Sharp flash chips

Mapping drivers for chip access-->

<*>CFI flash device mapped on S3C2410

Miscellaneous filesystems-->

<*>Journalling Flash File System v2 (JFFS2) support

<*>Compressed ROM file system support (cramfs)

# make zImage

四、建立设备文件

# mknod -m 666 mtd0 c 90 0

# mknod -m 666 mtd1 c 90 2

# mknod -m 666 mtd2 c 90 4

# mknod -m 666 mtd3 c 90 6

# mknod -m 666 mtd4 c 90 8

# mknod -m 666 mtd5 c 90 10

# mknod -m 666 mtdblock0 b 31 0

# mknod -m 666 mtdblock1 b 31 1

# mknod -m 666 mtdblock2 b 31 2

# mknod -m 666 mtdblock3 b 31 3

# mknod -m 666 mtdblock4 b 31 4

# mknod -m 666 mtdblock5 b 31 5

五、驱动文件s3c2410.c

#include

#include

#include

#include

#include

#include

#include

#include

#ifdef CONFIG_MTD_PARTITIONS

#include

#endif

#define WINDOW_ADDR 0x01000000

#define WINDOW_SIZE 0x800000

#define BUSWIDTH 2

#define FLASH_BLOCKSIZE_MAIN0x20000

#define FLASH_NUMBLOCKS_MAIN128

#define PROBETYPES { "cfi_probe", NULL }

#define MSG_PREFIX "S3C2410-NOR:"

#define MTDID "s3c2410-nor"

static struct mtd_info *mymtd;

struct map_info s3c2410nor_map = {

.name = "NOR flash on S3C2410",

.size = WINDOW_SIZE,

.bankwidth = BUSWIDTH,

.phys = WINDOW_ADDR,

};

#ifdef CONFIG_MTD_PARTITIONS

static struct mtd_partition static_partitions[] =

{

{

.name = "BootLoader",

.size = 0x040000,

.offset = 0x0

},

{

.name = "Kernel",

.size = 0x0100000,

.offset = 0x40000

},

{

.name = "RamDisk",

.size = 0x400000,

.offset = 0x140000

},

{

.name = "cramfs(2MB)",

.size = 0x200000,

.offset = 0x540000

},

{

.name = "jffs2(0.75MB)",

.size = 0xc0000,

.offset = 0x740000

},

};

//static const char *probes[] = { "RedBoot", "cmdlinepart", NULL };

static const char *probes[] = { NULL };

#endif

static int mtd_parts_nb = 0;

static struct mtd_partition *mtd_parts = 0;

int __init init_s3c2410nor(void)

{

static const char *rom_probe_types[] = PROBETYPES;

const char **type;

const char *part_type = 0;

printk(KERN_NOTICE MSG_PREFIX "0xx at 0xx\n",

WINDOW_SIZE, WINDOW_ADDR);

s3c2410nor_map.virt = ioremap(WINDOW_ADDR, WINDOW_SIZE);

if (!s3c2410nor_map.virt) {

printk(MSG_PREFIX "failed to ioremap\n");

return -EIO;

}

simple_map_init(&s3c2410nor_map);

mymtd = 0;

type = rom_probe_types;

for(; !mymtd && *type; type++) {

mymtd = do_map_probe(*type, &s3c2410nor_map);

}

if (mymtd) {

mymtd->owner = THIS_MODULE;

#ifdef CONFIG_MTD_PARTITIONS

mtd_parts_nb = parse_mtd_partitions(mymtd, probes, &mtd_parts, MTDID);

if (mtd_parts_nb > 0)

part_type = "detected";

if (mtd_parts_nb == 0)

{

mtd_parts = static_partitions;

mtd_parts_nb = ARRAY_SIZE(static_partitions);

part_type = "static";

}

#endif

add_mtd_device(mymtd);

if (mtd_parts_nb == 0)

printk(KERN_NOTICE MSG_PREFIX "no partition info available\n");

else

{

printk(KERN_NOTICE MSG_PREFIX

"using %s partition definition\n", part_type);

add_mtd_partitions(mymtd, mtd_parts, mtd_parts_nb);

}

return 0;

}

iounmap((void *)s3c2410nor_map.virt);

return -ENXIO;

}

static void __exit cleanup_s3c2410nor(void)

{

if (mymtd) {

del_mtd_device(mymtd);

map_destroy(mymtd);

}

if (s3c2410nor_map.virt) {

iounmap((void *)s3c2410nor_map.virt);

s3c2410nor_map.virt = 0;

}

}

module_init(init_s3c2410nor);

module_exit(cleanup_s3c2410nor);

MODULE_LICENSE("GPL");

MODULE_AUTHOR("GengYaoJun ");

MODULE_DESCRIPTION("Generic configurable MTD map driver");