S3C2410上Jffs2的移植

2007-12-25 10:06:19





参照llg写的关于hharm（e28f128flash）上的jffs2的移植
具体如下：

1.移植环境：
CPU：ARMS3C2410
Linux version:2.4.18
Flash：Intel E28F128

2.修改设备号
由于ROM设备和MTDBlock设备的主设备号（major）都是31，所以如果你不想把JFFS2作为根文件系统的话，必须修改他们之一的major。如果你要修改JFFS2的设备major，在uClinux-dist/linux-2.4.x/include/linux/mtd/mtd.h中把
＃define MTD_BLOCK_MAJOR 31
改成
＃define MTD_BLOCK_MAJOR 30

3.编写Maps文件
添加在flash上的map文件。在HHARM2410-R3/kernel/drivers/mtd/maps下添加flash(e28f128j3a-150)的map，我把握的文件内容贴上，仅供参考：
S3c2410_wpq.c
/*
* Normal mappings of chips on Samsung s3c2410 in physical memory
*/
#include >linux/module.h<
#include >linux/types.h<
#include >linux/kernel.h<
#include >asm/io.h<
#include >linux/mtd/mtd.h<
#include >linux/mtd/map.h<
#include >linux/mtd/partitions.h<
#include >linux/config.h<
#define WINDOW_ADDR 0x01000000 //基地址
#define WINDOW_SIZE 0x01600000 //flash大小 16M
#define BUSWIDTH 2
static struct mtd_info *mymtd;
__u8 s3c2410_read8(struct map_info *map, unsigned long ofs)
{
return readb(map-//以下是分区的内容，当然要根据你自己的需要确定了
static struct mtd_partition s3c2410_partitions[] = {
{
name: "reserved for bootloader",
size: 0x040000,
offset: 0x0,
mask_flags: MTD_WRITEABLE,
},
{
name: "reserved for kernel",
size: 0x0100000,
offset: 0x040000,
mask_flags: MTD_WRITEABLE,
},
{
name: "reserved for ramdisk",
size: 0x400000,
offset: 0x140000,
mask_flags: MTD_WRITEABLE,
},
{
name: "jffs2(8M)",
size: 0x800000,
offset: 0x800000,
}
};
int __init init_s3c2410(void)
{
printk(KERN_NOTICE "s3c2410 flash device: %x at %x/n", WINDOW_SIZE, WINDOW_ADDR);
s3c2410_map.map_priv_1 = (unsigned long)ioremap(WINDOW_ADDR, WINDOW_SIZE);
//printk("0/n");
if (!s3c2410_map.map_priv_1) {
printk("Failed to ioremap/n");
return -EIO;
}
//printk("1/n");
mymtd = do_map_probe("jedec_probe", &s3c2410_map);
if (!mymtd)
mymtd = do_map_probe("cfi_probe", &s3c2410_map);
//printk("2/n");
if (mymtd) {
mymtd-这里要特别注意Memory Technology Devices (MTD)的选项支持及其子项
RAM/ROM/Flash chip drivers ---<
Mapping drivers for chip access ---<
的选项支持；
还有File systems下选项支持。
##################################
***********************
#############################################
Linux Kernel v2.4.18-rmk7-pxa1 Configuration
Linux Kernel v2.4.18-rmk7-pxa1 Configuration
------------------------------------------------------------------------------
+-------------------- Memory Technology Devices (MTD) --------------------+
| Arrow keys navigate the menu. >Enter< selects submenus ---<. |
| Highlighted letters are hotkeys. Pressing >Y< includes, >N< excludes, |
| >M< modularizes features. Press >Esc<>Esc< to exit, >?< for Help. |
| Legend: [*] built-in [ ] excluded >M< module > < module capable |
| +---------------------------------------------------------------------+ |
| | >*< Memory Technology Device (MTD) support | |
| | [*] Debugging | |
| | (3) Debugging verbosity (0 = quiet, 3 = noisy) | |
| | >*< MTD partitioning support | |
| | >*< MTD concatenating support | |
| | > < RedBoot partition table parsing | |
| | > < Command line partition table parsing | |
| | > < ARM Firmware Suite partition parsing | |
| | --- User Modules And Translation Layers | |
| | >*< Direct char device access to MTD devices | |
| | >*< Caching block device access to MTD devices | |
| > < FTL (Flash Translation Layer) support | |
| | > < NFTL (NAND Flash Translation Layer) support | |
| | RAM/ROM/Flash chip drivers ---< | |
| | Mapping drivers for chip access ---< | |
| | Self-contained MTD device drivers ---< | |
| | NAND Flash Device Drivers ---< | |
| +---------------------------------------------------------------------+ |
+------------------------
| +---------v(+)--------------------------------------------------------+ |
+-------------------------------------------------------------------------+
| >Select< > Exit < > Help < |
+---------------------------------------------------
Linux Kernel v2.4.18-rmk7-pxa1 Configuration
------------------------------------------------------------------------------
+---------------------- RAM/ROM/Flash chip drivers -----------------------+
| Arrow keys navigate the menu. >Enter< selects submenus ---<. |
| Highlighted letters are hotkeys. Pressing >Y< includes, >N< excludes, |
| >M< modularizes features. Press >Esc<>Esc< to exit, >?< for Help. |
| Legend: [*] built-in [ ] excluded >M< module > < module capable |
| +---------------------------------------------------------------------+ |
| |>*< Detect flash chips by Common Flash Interface (CFI) probe | |
| |>*< Detect JEDEC JESD21c compatible flash chips | |
| |[ ] Flash chip driver advanced configuration options | |
| |>*< Support for Intel/Sharp flash chips | |
| |> < Support for AMD/Fujitsu flash chips | |
| |> < Support for RAM chips in bus mapping | |
| |> < Support for ROM chips in bus mapping | |
| |> < Support for absent chips in bus mapping | |
| |[ ] Older (theoretically obsoleted now) drivers for non-CFI chips | |
| | | |
| | | |
| +---------------------------------------------------------------------+ |
+-------------------------------------------------------------------------+
| >Select< > Exit < > Help < |
+-------------------------------------------------------------------------+
Linux Kernel v2.4.18-rmk7-pxa1 Configuration
------------------------------------------------------------------------------
+-------------------- Mapping drivers for chip access --------------------+
| Arrow keys navigate the menu. >Enter< selects submenus ---<. |
| Highlighted letters are hotkeys. Pressing >Y< includes, >N< excludes, |
| >M< modularizes features. Press >Esc<>Esc< to exit, >?< for Help. |
| Legend: [*] built-in [ ] excluded >M< module > < module capable |
| +---------------------------------------------------------------------+ |
| | >*< CFI Flash device in physical memory map | |
| | (800000) Physical start address of flash mapping | |
| | (800000) Physical length of flash mapping | |
| | (2) Bus width in octets | |
| | >*< CFI Flash device mapped on S3C2410 | |
| | | |
| | | |
| | | |
| | | |
| | | |
| | | |
| +---------------------------------------------------------------------+ |
+-------------------------------------------------------------------------+
| >Select< > Exit < > Help < |
+-------------------------------------------------------------------------+
Linux Kernel v2.4.18-rmk7-pxa1 Configuration
------------------------------------------------------------------------------
+----------------------------- File systems ------------------------------+
| Arrow keys navigate the menu. >Enter< selects submenus ---<. |
| Highlighted letters are hotkeys. Pressing >Y< includes, >N< excludes, |
| >M< modularizes features. Press >Esc<>Esc< to exit, >?< for Help. |
| Legend: [*] built-in [ ] excluded >M< module > < module capable |
| +---------------------------------------------------------------------+ |
| | [ ] Quota support | |
| | > < Kernel automounter support | |
| | > < Kernel automounter version 4 support (also supports v3) | |
| | > < Reiserfs support | |
| | > < ADFS file system support | |
| | > < Amiga FFS file system support (EXPERIMENTAL) | |
| | > < Apple Macintosh file system support (EXPERIMENTAL) | |
| | > < BFS file system support (EXPERIMENTAL) | |
| | >*< Ext3 journalling file system support (EXPERIMENTAL) | |
| | [ ] JBD (ext3) debugging support | |
| | >*< DOS FAT fs support | |
| > < MSDOS fs support | |
| | >*< VFAT (Windows-95) fs support | |
| | > < EFS file system support (read only) (EXPERIMENTAL) | |
| | > < Journalling Flash File System (JFFS) support | |
| | >*< Journalling Flash File System v2 (JFFS2) support | |
| | (2) JFFS2 debugging verbosity (0 = quiet, 2 = noisy) | |
| | >*< Compressed ROM file system support | |
| | [*] Virtual memory file system support (former shm fs) | |
| | >*< Simple RAM-based file system support | |
| | > < ISO 9660 CDROM file system support | |
| | > < Minix fs support
| > < FreeVxFS file system support (VERITAS VxFS(TM) compatible) | |
| | > < NTFS file system support (read only) | |
| | > < OS/2 HPFS file system support | |
| | [*] /proc file system support | |
| | [*] /dev file system support (EXPERIMENTAL) | |
| | [*] Automatically mount at boot | |
| | [ ] Debug devfs | |
| | [*] /dev/pts file system for Unix98 PTYs | |
| | > < QNX4 file system support (read only) (EXPERIMENTAL) | |
| | > < ROM file system support | |
| | >*< Second extended fs support
| [ ] Debug devfs | |
| | [*] /dev/pts file system for Unix98 PTYs | |
| | > < QNX4 file system support (read only) (EXPERIMENTAL) | |
| | > < ROM file system support | |
| | >*< Second extended fs support | |
| | > < System V/Xenix/V7/Coherent file system support | |
| | > < UDF file system support (read only) | |
| | > < UFS file system support (read only) | |
| | Network File Systems ---< | |
| | Partition Types ---< | |
| | Native Language Support ---<
| +--v(+)---------------------------------------------------------------+ |
+-------------------------------------------------------------------------+
| >Select< > Exit < > Help < |
+-------------------------------------------------------------------------+

7．制作jffs2映象
首先取得jffs2的制作工具：mkfs.jffs2（可从网上取得）
执行如下命令即可生成所要的映象：
chmod 777 mkfs.jffs2 //取得mkfs.jffs2的执行权限，即mkfs.jffs2成为可执行文件
./mkfs.jffs2 －d jffs2/ －o jffs2.img //生成jffs2文件映象，其中目录jffs2可以是任意的目录，这里的jffs2是我新建的一个目录

8．Jffs2的应用
对于ppcboot、zImage、ramdisk.image.gz向romfs一样正常烧写；
以上三项烧写完之后，接着烧写jffs2.img，具体烧写如下：
tftp 30800000 jffs2.img
fl 1800000 30800000 20000 （其中20000可根据jffs2的大小适当调整，理论上只要比jffs2.img略大即可，但要为20000的整数倍）
特别注意：要想使我们做的jffs2文件系统更加的人性化，我们还可以在ramdisk.image.gz的mnt/etc/init.d/rc$文件中加入如下指令以便启动时自动挂载jffs2文件系统。
Mount －t jffs2 /dev/mtdblock/4 /mnt //其中的/dev/mtdblock/4是flash上的jffs2分区。

9．以上配置烧写完成之后就可启动我们的系统，对jffs2分区尽情的添加和删除了，添加的东东再不会因断电而丢失了，呵呵就到这了。