嵌入式系统移植三步曲
Bootloader的移植————>Linux的移植----->根文件系统的移植
班机：09应用技术二班 姓名：贾文龙 学号：0906042030
一、Bootloader的移植
1．编辑u-boot根目录中的Makefile文件将ifeq ($(ARCH),arm)
CROSS_COMPILE = arm-linux-
endif
改为
ifeq ($(ARCH),arm)
CROSS_COMPILE=/usr/local/arm/2.95.3/bin/arm-linux-
endif
在
smdk2410_config : unconfig
@./mkconfig $(@:_config=) arm arm920t smdk2410 NULL s3c24x0
后面添加
ok2410_config : unconfig
@./mkconfig $(@:_config=) arm arm920t ok2410 NULL s3c24x0
2．复制必要的文件，编辑ok2410.h头文件
[root@localhost u-boot-1.1.4]# mkdir board/ok2410
[root@localhost u-boot-1.1.4]# cp board/smdk2410/* board/ok2410/
[root@localhost u-boot-1.1.4]# mv board/ok2410/smdk2410.c board/ok2410/ok2410.c
[root@localhost u-boot-1.1.4]# cp include/configs/smdk2410.h include/configs/ok2410.h
[root@localhost u-boot-1.1.4]# gedit include/configs/ok2410.h
将
OBJS := smdk2410.o flash.o
改为
OBJS := ok2410.o flash.o
3．配置、编译u-boot[root@localhost u-boot-1.1.4]# make ok2410_config
修改cpu/arm920t/config.mk文件
|
将 PLATFORM_CPPFLAGS +=$(call cc-option,-mapcs-32,-mabi=apcs-gnu) 改成： PLATFORM_CPPFLAGS +=$(call cc-option,-mapcs-32,$(call cc-option,-mabi=apcs-gnu,)) |
修改examples目录下的Makefile文件
将原文件的第58行开始的内容：
SREC = hello_world.srec
BIN = hello_world.bin hello_world
改为
SREC = hello_world.o
BIN = hello_world.o hello_world
[root@localhost u-boot-1.1.4]# make
|
make[1]: Leaving directory `/root/Desktop/u-boot-1.1.4/common' UNDEF_SYM=`/usr/local/arm/2.95.3/bin/arm-linux-objdump -x lib_generic/libgeneric.a board/ok2410/libok2410.a cpu/arm920t/libarm920t.a cpu/arm920t/s3c24x0/libs3c24x0.a lib_arm/libarm.a fs/cramfs/libcramfs.a fs/fat/libfat.a fs/fdos/libfdos.a fs/jffs2/libjffs2.a fs/reiserfs/libreiserfs.a fs/ext2/libext2fs.a net/libnet.a disk/libdisk.a rtc/librtc.a dtt/libdtt.a drivers/libdrivers.a drivers/sk98lin/libsk98lin.a post/libpost.a post/cpu/libcpu.a common/libcommon.a |sed -n -e 's/.*(__u_boot_cmd_.*)/-u1/p'|sort|uniq`; /usr/local/arm/2.95.3/bin/arm-linux-ld -Bstatic -T /root/Desktop/u-boot-1.1.4/board/ok2410/u-boot.lds -Ttext 0x33F80000 $UNDEF_SYM cpu/arm920t/start.o --start-group lib_generic/libgeneric.a board/ok2410/libok2410.a cpu/arm920t/libarm920t.a cpu/arm920t/s3c24x0/libs3c24x0.a lib_arm/libarm.a fs/cramfs/libcramfs.a fs/fat/libfat.a fs/fdos/libfdos.a fs/jffs2/libjffs2.a fs/reiserfs/libreiserfs.a fs/ext2/libext2fs.a net/libnet.a disk/libdisk.a rtc/librtc.a dtt/libdtt.a drivers/libdrivers.a drivers/sk98lin/libsk98lin.a post/libpost.a post/cpu/libcpu.a common/libcommon.a --end-group -L /usr/local/arm/2.95.3/lib/gcc-lib/arm-linux/2.95.3 -lgcc -Map u-boot.map -o u-boot /usr/local/arm/2.95.3/bin/arm-linux-objcopy --gap-fill=0xff -O srec u-boot u-boot.srec /usr/local/arm/2.95.3/bin/arm-linux-objcopy --gap-fill=0xff -O binary u-boot u-boot.bin |
[root@localhost u-boot-1.1.4]# gedit skyeye.conf
|
# skyeye config file for S3C2410X cpu: arm920t mach: s3c2410x # physical memory mem_bank: map=M, type=RW, addr=0x00000000, size=0x00800000, file=./u-boot.bin ,boot=yes mem_bank: map=M, type=RW, addr=0x30000000, size=0x00800000 mem_bank: map=M, type=RW, addr=0x30800000, size=0x00800000 mem_bank: map=M, type=RW, addr=0x31000000, size=0x03000000 # all peripherals I/O mapping area mem_bank: map=I, type=RW, addr=0x48000000, size=0x20000000 mem_bank: map=I, type=RW, addr=0x19000300, size=0x00000020
net: type=cs8900a, base=0x19000300, size=0x20,int=9, mac=08:00:3E:26:0A:5B, ethmod=tuntap, hostip=10.0.0.1 nandflash: type=s3c2410x,name=K9F1208U0B,dump=./nand.dump #lcd:type=s3c2410x, mod=gtk dbct:state=on |
[root@localhost u-boot-1.1.4]# gedit cpu/arm920t/start.S
将从NOR Flash启动改成从NAND Flash启动。
6．修改board/ok2410/Makefile将
OBJS := ok2410.o flash.o
改为
OBJS := ok2410.o flash.o nand_read.o
7．创建board/ok2410/nand_read.c文件
#include
#define __REGb(x) (*(volatile unsigned char *)(x))
#define __REGi(x) (*(volatile unsigned int *)(x))
#define NF_BASE 0x4e000000
#define NFCONF __REGi(NF_BASE + 0x0)
#define NFCMD __REGb(NF_BASE + 0x4)
#define NFADDR __REGb(NF_BASE + 0x8)
#define NFDATA __REGb(NF_BASE + 0xc)
#define NFSTAT __REGb(NF_BASE + 0x10)
#define BUSY 1
#ifndef NAND_SECTOR_SIZE
#define NAND_SECTOR_SIZE 512
#endif
#ifndef NAND_BLOCK_MASK
8．编辑include/configs/ok2410.h文件
在文件的后部添加
/****************** me add begin *******************/
/*
* Nandflash Boot
*/
#define CONFIG_S3C2410_NAND_BOOT 1
#define STACK_BASE 0x33f00000
#define STACK_SIZE 0x8000
//#define UBOOT_RAM_BASE 0x33f80000
/* NAND Flash Controller */
#define NAND_CTL_BASE 0x4E000000
#define bINT_CTL(Nb) __REG(INT_CTL_BASE + (Nb))
/* Offset */
#define oNFCONF 0x00
#define oNFCMD 0x04
#define oNFADDR 0x08
#define oNFDATA 0x0c
#define oNFSTAT 0x10
#define oNFECC 0x14
/****************** me add end *******************/
9．编译u-boot，然后测试u-boot是否可以从nand启动
[root@localhost u-boot-1.1.4]# make
[root@localhost u-boot-1.1.4]# skyeye1.2.6
……
Loaded RAM ./u-boot.bin
到此停止不动，需要执行如下命令：
[root@localhost u-boot-1.1.4]# mknandflashdump u-boot.bin nand.dump 0
Bash:mknandflashdump:command not found
解决：
[root@localhost u-boot-1.1.4]# gcc -g mknandflashdump.c
[root@localhost u-boot-1.1.4]# mknandflashdump u-boot.bin nand.dump 0
offset: 0x0 = 0
1 pos: 0x0 = 0
2 pos: 0x0 = 0
finish
[root@localhost u-boot-1.1.4]# ll nand.dump
|
-rw-r--r-- 1 root root 118272 05-10 22:29 nand.dump |
[root@localhost u-boot-1.1.4]# chmod 666 nand.dump
10．编辑include/configs/ok2410.h文件
在
#define CONFIG_BAUDRATE 115200
后面添加
/*********************** me add begin *************************************/
/* enable passing of ATAGs */
#define CONFIG_CMDLINE_TAG 1
#define CONFIG_SETUP_MEMORY_TAGS 1
#define CONFIG_INITRD_TAG 1
/*********************** me add end *************************************/
将
/*CFG_CMD_NAND |*/
改为
CFG_CMD_NAND |
将
/*#define CONFIG_BOOTARGS "root=ramfs devfs=mount console=ttySA0,9600" */
改为
#define CONFIG_BOOTARGS "noinitrd root=/dev/nfs rw nfsroot=10.0.0.1:/tmp/nfs ip=10.0.0.110:10.0.0.1:10.0.0.1:255.255.255.0 init=linuxrc console=ttySAC0,115200 mem=64M"
将
/*#define CONFIG_BOOTCOMMAND "tftp; bootm" */
改为
#define CONFIG_BOOTCOMMAND "tftp 0x31000000 uImage;bootm 0x31000000"
/****************** me add begin *******************/
// #define CFG_ENV_IS_IN_FLASH 1 /*将该行注释，添加下面一行*/
#define CFG_ENV_IS_IN_NAND 1 /*该行很重要，没有该行，saveenv命令将失效*/
#define CFG_ENV_SIZE 0x10000 /* Total Size of Environment Sector */
#define CFG_NAND_LEGACY 1
#define CFG_ENV_OFFSET 0X20000 /*环境变量在Nand Flash的0x20000处*/
#if (CONFIG_COMMANDS & CFG_CMD_NAND)
#define CFG_NAND_BASE 0x4E000000 /* physical address to access nand at CS0*/
/* Nand Flash控制器在SFR区起始寄存器地址 */
#define CFG_MAX_NAND_DEVICE 1 /*支持Nand Flash设备的最大个数*/
#define SECTORSIZE 512
#define NAND_SECTOR_SIZE SECTORSIZE
#define NAND_BLOCK_MASK 511
#define ADDR_COLUMN 1
#define ADDR_PAGE 3
#define ADDR_COLUMN_PAGE 4
#define NAND_ChipID_UNKNOWN 0x00 /* 未知芯片的ID号 */
#define NAND_MAX_FLOORS 1
#define NAND_MAX_CHIPS 1 /* 板子上NAND Flash芯片的最大个数 */
/*下面7行是Nand Flash命令层底层的接口函数 */
#define WRITE_NAND_COMMAND(d, adr) {rNFCMD = d;}
#define WRITE_NAND_ADDRESS(d, adr) {rNFADDR = d;}
#define WRITE_NAND(d, adr) {rNFDATA = d;}
#define READ_NAND(adr) (rNFDATA)
#define NAND_WAIT_READY(nand) {while(!(rNFSTAT&(1<<0)));}
#define NAND_DISABLE_CE(nand) {rNFCONF |= (1<<11);}
#define NAND_ENABLE_CE(nand) {rNFCONF &= ~(1<<11);}
/* the following functions are NOP's because S3C24X0 handles this in hardware */
#define NAND_CTL_CLRALE(nandptr)
#define NAND_CTL_SETALE(nandptr)
#define NAND_CTL_CLRCLE(nandptr)
#define NAND_CTL_SETCLE(nandptr)
#define CONFIG_MTD_NAND_VERIFY_WRITE 1 /* 允许Nand Flash写校验 */
/*
* Nandflash Boot
*/
#define CONFIG_S3C2410_NAND_BOOT 1
#define STACK_BASE 0x33f00000
#define STACK_SIZE 0x8000
//#define UBOOT_RAM_BASE 0x33f80000
/* NAND Flash Controller */
#define NAND_CTL_BASE 0x4E000000
#define bINT_CTL(Nb) __REG(INT_CTL_BASE + (Nb))
/* Offset */
#define oNFCONF 0x00
#define oNFCMD 0x04
#define oNFADDR 0x08
#define oNFDATA 0x0c
#define oNFSTAT 0x10
#define oNFECC 0x14
#define rNFCONF (*(volatile unsigned int *)0x4e000000)
#define rNFCMD (*(volatile unsigned char *)0x4e000004)
#define rNFADDR (*(volatile unsigned char *)0x4e000008)
#define rNFDATA (*(volatile unsigned char *)0x4e00000c)
#define rNFSTAT (*(volatile unsigned int *)0x4e000010)
#define rNFECC (*(volatile unsigned int *)0x4e000014)
#define rNFECC0 (*(volatile unsigned char *)0x4e000014)
#define rNFECC1 (*(volatile unsigned char *)0x4e000015)
#define rNFECC2 (*(volatile unsigned char *)0x4e000016)
#endif /* CONFIG_COMMANDS & CFG_CMD_NAND*/
/****************** me add end *******************/
11．编辑board/ok2410/ok2410.c文件
在文件的尾部添加如下内容：
/****************** me add begin *******************/
#if (CONFIG_COMMANDS & CFG_CMD_NAND)
typedef enum {
NFCE_LOW,
NFCE_HIGH
} NFCE_STATE;
static inline void NF_Conf(u16 conf)
{
S3C2410_NAND * const nand = S3C2410_GetBase_NAND();
nand->NFCONF = conf;
}
static inline void NF_Cmd(u8 cmd)
{
S3C2410_NAND * const nand = S3C2410_GetBase_NAND();
nand->NFCMD = cmd;
}
static inline void NF_CmdW(u8 cmd)
{
NF_Cmd(cmd);
udelay(1);
}
static inline void NF_Addr(u8 addr)
{
S3C2410_NAND * const nand = S3C2410_GetBase_NAND();
nand->NFADDR = addr;
}
static inline void NF_SetCE(NFCE_STATE s)
{
S3C2410_NAND * const nand = S3C2410_GetBase_NAND();
switch (s) {
case NFCE_LOW:
nand->NFCONF &= ~(1<<11);
break;
case NFCE_HIGH:
nand->NFCONF |= (1<<11);
break;
}
}
static inline void NF_WaitRB(void)
{
S3C2410_NAND * const nand = S3C2410_GetBase_NAND();
while (!(nand->NFSTAT & (1<<0)));
}
static inline void NF_Write(u8 data)
{
S3C2410_NAND * const nand = S3C2410_GetBase_NAND();
nand->NFDATA = data;
}
static inline u8 NF_Read(void)
{
S3C2410_NAND * const nand = S3C2410_GetBase_NAND();
return(nand->NFDATA);
}
static inline void NF_Init_ECC(void)
{
S3C2410_NAND * const nand = S3C2410_GetBase_NAND();
nand->NFCONF |= (1<<12);
}
static inline u32 NF_Read_ECC(void)
{
S3C2410_NAND * const nand = S3C2410_GetBase_NAND();
return(nand->NFECC);
}
#endif
/*
* NAND flash initialization.
*/
#if (CONFIG_COMMANDS & CFG_CMD_NAND)
extern ulong nand_probe(ulong physadr);
static inline void NF_Reset(void)
{
int i;
NF_SetCE(NFCE_LOW);
NF_Cmd(0xFF); /* reset command */
for(i = 0; i < 10; i++); /* tWB = 100ns. */
NF_WaitRB(); /* wait 200~500us; */
NF_SetCE(NFCE_HIGH);
}
static inline void NF_Init(void)
{
#if 0 /* a little bit too optimistic */
#define TACLS 0
#define TWRPH0 3
#define TWRPH1 0
#else
#define TACLS 0
#define TWRPH0 4
#define TWRPH1 2
#endif
NF_Conf((1<<15)|(0<<14)|(0<<13)|(1<<12)|(1<<11)|(TACLS<<8)|(TWRPH0<<4)|(TWRPH1<<0));
/*nand->NFCONF = (1<<15)|(1<<14)|(1<<13)|(1<<12)|(1<<11)|(TACLS<<8)|(TWRPH0<<4)|(TWRPH1<<0); */
/* 1 1 1 1, 1 xxx, r xxx, r xxx */
/* En 512B 4step ECCR nFCE=H tACLS tWRPH0 tWRPH1 */
NF_Reset();
}
void nand_init(void)
{
S3C2410_NAND * const nand = S3C2410_GetBase_NAND();
NF_Init();
#ifdef DEBUG
printf("NAND flash probing at 0x%.8lX ", (ulong)nand);
#endif
printf ("%4lu MB ", nand_probe((ulong)nand) >> 20);
}
#endif
/****************** me add end *******************/
12修改 common/cmd_nand.c文件将NanD_ReadBuf函数中的
NanD_Command (nand, NAND_CMD_READ0);
注释
13．编译、测试[root@localhost u-boot-1.1.4]# make
[root@localhost u-boot-1.1.4]# ./mknandflashdump u-boot.bin nand.dump 0
[root@localhost u-boot-1.1.4]# skyeye1.2.6
In: serial
Out: serial
Err: serial
Hit any key to stop autoboot: 0
TFTP from server 10.0.0.1; our IP address is 10.0.0.110
Filename 'uImage'.
Load address: 0x31000000
Loading: checksum bad
T T T T T T T T
解决：建立tftp服务器并修改权限
#chmod-R 755 /tftpboot;
二、Linux的移植
1．解压linux-2.6.14.7.tar.bz2
[root@localhost Desktop]# tar -xjvf linux-2.6.14.7.tar.bz2 -C ./
2．编辑Makefile文件
将
ARCH ?= $(SUBARCH)
CROSS_COMPILE ?=
改为
ARCH ?= arm
CROSS_COMPILE ?= /usr/local/arm/3.4.1/bin/arm-linux- // linux2.6.14的交叉编译器为gcc-3.4.1
3．复制cs8900
[root@localhost linux-2.6.14.7]# cp ../cs8900/cs8900.c drivers/net/arm/
[root@localhost linux-2.6.14.7]# cp ../cs8900/cs8900.h drivers/net/arm/
cp: 无法 stat “../cs8900/cs8900.c”: 没有那个文件或目录
解决：在../下建立cs8900目录
4．修改drivers/net/arm/目录下的Kconfig文件
在最后添加如下内容：
config ARM_CS8900
tristate "CS8900 support"
depends on NET_ETHERNET && ARM && ARCH_SMDK2410
help
Support for CS8900A chipset based Ethernet cards. If you have a network
(Ethernet) card of this type, say Y and read the Ethernet-HOWTO, available
from as well as .To compile this driver as a module, choose M here and read.
The module will be called cs8900.o.
5．修改drivers/net/arm/目录下的Makefile文件在文件最后添加如下内容：
obj-$(CONFIG_ARM_CS8900) += cs8900.o
6、编辑arch/arm/mach-s3c2410/mach-smdk2410.c文件添加一个头文件
#include
将
static struct map_desc smdk2410_iodesc[] __initdata = {
/* nothing here yet */
};
改为
static struct map_desc smdk2410_iodesc[] __initdata = {
/* nothing here yet */
/* Map the ethernet controller CS8900A */
{ vSMDK2410_ETH_IO, pSMDK2410_ETH_IO, SZ_1M, MT_DEVICE }
};
7、在include/asm-arm/arch-s3c2410/目录下创建smdk2410.h文件文件的内容如下
#ifndef _INCLUDE_SMDK2410_H_
#define _INCLUDE_SMDK2410_H_
#include
#define pSMDK2410_ETH_IO 0x19000000
#define vSMDK2410_ETH_IO 0xE0000000
#define SMDK2410_ETH_IRQ IRQ_EINT9
#endif // _INCLUDE_SMDK2410_H_
8．设置Flash分区
在此要编辑3个文件：devs.c、mach-smdk2410.c、s3c2410.c。
（1）编辑devs.c文件，指明分区信息
[root@localhost linux-2.6.14.7]# gedit arch/arm/mach-s3c2410/devs.c
添加内容并修改该文件中s3c_device_nand结构体变量，添加对dev成员的赋值。
struct platform_device s3c_device_nand = {
.name = "s3c2410-nand", /* device name */
.id = -1, /* device id */
.num_resources = ARRAY_SIZE(s3c_nand_resource),
.resource = s3c_nand_resource, /* Nand Flash Controller Registers */
.dev = /* Add the Nand Flash device */
{
.platform_data = &superlpplatform
}
};
(2）编辑mach-smdk2410.c文件，指定启动时初始化
kernel启动时依据对分区的设置进行初始化。
[root@localhost linux-2.6.14.7]# gedit arch/arm/mach-s3c2410/mach-smdk2410.c
修改smdk2410_devices[]，指明初始化时，包括前面设置的Flash分区信息。
/* 添加如下语句 */
&s3c_device_nand,
（3）编辑s3c2410.c文件，禁止Flash ECC校验
[root@localhost linux-2.6.14.7]# gedit drivers/mtd/nand/s3c2410.c
在s3c2410_nand_init_chip()函数中。
将
chip->eccmode = NAND_ECC_SOFT;
改为
chip->eccmode = NAND_ECC_NONE;
9．配置内核
(1）支持启动时挂载devfs
为了让内核支持devfs，以及在启动时/sbin/init运行之前，能够自动挂载/dev为devfs文件系统，需要编辑fs/Kconfig文件。
[root@localhost linux-2.6.14.7]# gedit fs/Kconfig
找到menu "Pseudo filesystems"
添加如下语句：
config DEVFS_FS
bool "/dev file system support (OBSOLETE)"
default y
config DEVFS_MOUNT
bool "Automatically mount at boot"
default y
depends on DEVFS_FS
（2）配置内核，产生.config文件
[root@localhost linux-2.6.14.7]# make smdk2410_defconfig
[root@localhost linux-2.6.14.7]# make menuconfig
弹出的TUI界面中，进行配置
10．编译内核，创建uImage，将uImage复制到tftp服务器的根目录（/tftpboot/）
[root@localhost linux-2.6.14.7]# make
CHK include/linux/version.h
make[1]: “include/asm-arm/mach-types.h”是最新的。
CHK include/linux/compile.h
CHK usr/initramfs_list
CC arch/arm/mach-s3c2410/devs.o
arch/arm/mach-s3c2410/devs.c:138: error: `superlpplatform' undeclared here (not in a function)
arch/arm/mach-s3c2410/devs.c:138: error: initializer element is not constant
arch/arm/mach-s3c2410/devs.c:138: error: (near initialization for `s3c_device_nand.dev.platform_data')
arch/arm/mach-s3c2410/devs.c:138: error: initializer element is not constant
arch/arm/mach-s3c2410/devs.c:138: error: (near initialization for `s3c_device_nand.dev')
make[1]: *** [arch/arm/mach-s3c2410/devs.o] 错误 1
make: *** [arch/arm/mach-s3c2410] 错误 2
解决：将添加的内容添加到源文件的头文件下面就行了！
然后[root@localhost linux-2.6.14.7]# make
[root@localhost linux-2.6.14.7]# cp arch/arm/boot/compressed/vmlinux ../u-boot-1.1.4/tools/
[root@localhost linux-2.6.14.7]# cd ../u-boot-1.1.4/tools/
[root@localhost tools]# ./mkimage -A arm -O linux -T kernel -C none -a 30008000 -e 30008000 -n linux-2.6.14.7 -d vmlinux uImage
[root@localhost tools]# cp uImage ../
[root@localhost tools]# cp initrd.img ../
cp: 无法 stat “initrd.img”: 没有那个文件或目录
解决：cp ../../initrd.img
[root@localhost tools]# cp uImage /tftpboot/
[root@localhost tools]# cp initrd.img /tftpboot/
cp: 无法 stat “initrd.img”: 没有那个文件或目录
解决：cp ../initrd.img
[root@localhost tools]# cp ../u-boot.bin /tftpboot/
[root@localhost tools]# cp ../initrd.img /tmp/nfs/
[root@localhost tools]# iptables -F
三、根文件系统的移植
1、解压busybox-1.13.4.tar.bz2
2．编辑Makefile文件
将
CROSS_COMPILE ?=
改为
CROSS_COMPILE ?=/usr/local/arm/3.4.1/bin/arm-linux-
将
ARCH ?= $(SUBARCH)
改为
ARCH ?= arm
3．进行默认配置[root@localhost busybox-1.13.4]# make defconfig //恢复默认配置
4．对配置信息进行修改
[root@localhost busybox-1.13.4]# make menuconfig
在弹出的TUI界面中进行配置
5．编译
[root@localhost busybox-1.13.4]# make
编译出错，此时需要编辑networking/interface.c文件
[root@localhost busybox-1.13.4]# gedit networking/interface.c
将networking/interface.c文件的818行修改为“.type = -1”，然后再次编译。
[root@localhost busybox-1.13.4]# make install
如果成功，会出现如下信息：
|
-------------------------------------------------- You will probably need to make your busybox binary setuid root to ensure all configured applets will work properly. -------------------------------------------------- |
修改_install/bin/busybox文件的属性
[root@localhost busybox-1.13.4]# chmod 4755 ./_install/bin/busybox
6、对配置信息进行修改 注意此处是在/tmp/nfs
（1）在/tmp/nfs中创建所需的目录
[root@localhost nfs]# mkdir -p bin sbin lib/modules etc/init.d dev usr/bin usr/sbin usr/lib proc sys home root boot mnt/etc mnt/jffs2 mnt/yaffs mnt/data mnt/temp var/lib var/lock var/log var/run var/tmp tmp
[root@localhost nfs]# chmod 1777 tmp
[root@localhost nfs]# chmod 1777 var/tmp
[root@localhost nfs]# cd dev/
[root@localhost dev]# mknod -m 600 console c 5 1 注意此处是在/tmp/nfs/dev中
[root@localhost dev]# mknod -m 666 null c 1 3 注意此处是在/tmp/nfs/dev中
（2）复制文件到/tmp/nfs中
将/root/Desktop/busybox-1.13.4/_install中的内容复制到/tmp/nfs中
注意此处转换目录进入/busybox-1.13.4/_install
[root@localhost _install]# cp -a bin /tmp/nfs/
[root@localhost _install]# cp -a sbin /tmp/nfs/
[root@localhost _install]# cp -a linuxrc /tmp/nfs/
[root@localhost _install]# cd ..
[root@localhost busybox-1.13.4]# cp -a examples/bootfloppy/etc/* /tmp/nfs/etc/
7．创建配置文件
（1）编写etc/inittab文件、修改其权限
文件内容如下：
::sysinit:/etc/init.d/rcS #指定系统初始化脚本文件
::respawn:-/bin/login #加上-语句会在登陆终端之后调用/etc/目录下的profile文件
::restart:/sbin/init #指定系统重启时执行的初始化程序
tty0::respawn:-/bin/login
::shutdown:/bin/umount -a -r #指定关机时执行的操
::shutdown:/sbin/swapoff -a
[root@localhost nfs]# chmod 755 etc/inittab
（2）编写etc/init.d/rcS文件、修改其权限
文件内容如下：
#!/bin/sh
# mount all filesystem defined in "fstab"
echo "#mount all......."
/bin/mount -a
/bin/mknod -m 600 /dev/console c 5 1
/bin/mknod -m 666 /dev/null c 1 3
/bin/mknod -m 666 /dev/tty0 c 4 0
/bin/mknod -m 666 /dev/mtdblock0 b 31 0
/bin/mknod -m 666 /dev/mtdblock1 b 31 1
/bin/mknod -m 666 /dev/mtdblock2 b 31 2
/bin/mknod -m 666 /dev/mtdblock3 b 31 3
#/bin/mount -t ext2 /dev/mtdblock3 /mnt/temp/
echo "******************************************************************"
echo " OK 2410 Rootfs made by JWL, 2011.06"
echo "******************************************************************"
[root@localhost nfs]# chmod 755 etc/init.d/rcS
（3）编写etc/fstab文件、修改其权限
文件内容如下：
proc /proc proc defaults 0 0
sysfs /sys sysfs defaults 0 0
none /tmp ramfs defaults 0 0
mdev /dev ramfs defaults 0 0
[root@localhost nfs]# chmod 755 etc/fstab
（4）编写etc/proflie文件、修改其权限
文件内容如下：
# /etc/profile: system-wide .profile file for the Bourne shells
echo
echo -n "Processing /etc/profile... "
# no-op
# Set search library path
echo "Set search library path in /etc/profile"
export LD_LIBRARY_PATH=/lib:/usr/lib
# Set user path
echo "Set user path in /etc/profile"
export PATH=/bin:/sbin:/usr/bin:/usr/sbin #设置命令搜索路径
export HISTSIZE=100
export PS1='[u@JWL W]$ '
alias ll='ls -l'
#/sbin/ifconfig eth0 192.168.1.22 netmask 255.255.255.0
/sbin/ifconfig lo 127.0.0.1
echo "Configure net done"
echo "All Done"
echo
（5）创建密码文件、修改其权限
[root@localhost nfs]# cp /etc/passwd etc/ ;cp /etc/shadow etc/ ;cp /etc/group etc/
[root@localhost nfs]# chmod 600 etc/shadow
[root@localhost nfs]# gedit etc/passwd
内容是：root::0:0:root:/root:/bin/sh
[root@localhost nfs]# gedit etc/shadow
内容是：root:$1$zs2zr2N4$15U99ll5tUm3DwOvKnCVV1:14335:0:99999:7:::
[root@localhost nfs]# gedit etc/group
内容是：root:x:0:root
（6）为mdev创建配置文件
[root@localhost nfs]# gedit etc/mdev.conf
内容是：空
（7）删除备份文件
[root@localhost nfs]# rm etc/*~ etc/init.d/*~
8．复制常用的库文件
编写脚本文件copy_lib.sh。
[root@localhost nfs]# gedit copy_lib.sh
#!/bin/bash
#You should put this file cp.sh in /usr/local/arm/3.4.1/arm-linux/lib/
ROOTFS_LIB=/tmp/nfs/lib/
for file in libc libcrypt libdl libm libpthread libresolv libutil
do
cp $file-*.so ${ROOTFS_LIB}
cp -d $file.so.[*0-9] ${ROOTFS_LIB}
done
cp -d ld*.so* ${ROOTFS_LIB}
[root@localhost nfs]# chmod a+x copy_lib.sh
[root@localhost nfs]# cp copy_lib.sh /usr/local/arm/3.4.1/arm-linux/lib/
[root@localhost nfs]# cd /usr/local/arm/3.4.1/arm-linux/lib/
[root@localhost lib]# ./copy_lib.sh
9．完整的启动过程（u-boot、内核、文件系统）
注意：在嵌入式系统开发的过程中，一般的做法是通过tftp将操作系统内核下载到开发板，内核引导时通过NFS挂载根文件系统，下面的操作过程既是如此。
（1）编辑/etc/xinetd.d/tftp文件
[root@localhost Desktop]# gedit /etc/xinetd.d/tftp
（2）重启tftp服务器
（3）编辑/etc/exports文件
文件内容如下：
/tmp/nfs *(rw,sync,no_root_squash)
（4）重启NFS服务器
（5）完整的启动过程（u-boot、内核、文件系统、用户程序（注意：通过u－boot引导内核要在 u-boot-1.1.4文件夹里）），使用NFS文件系统
[root@localhost u-boot-1.1.4]# skyeye1.2.6
10.0.0.110 login: root
Password:
login[25]: root login on 'console'
login: cannot run /bin/bash: Exec format error
解决：[root@localhost nfs]gedit etc/passwd
将：root:x:0:0:root:/root:/bin/bash
改为：root:x:0:0:root:/root:/bin/sh
[root@localhost u-boot-1.1.4]# skyeye1.2.6
******************************************************************
OK 2410 Rootfs made by JWL, 2011.06
******************************************************************
10.0.0.110 login: root
login[25]: root login on 'console'
Processing /etc/profile... Set search library path in /etc/profile
Set user path in /etc/profile
Configure net done
All Done
[root@JWL /root]#
[root@JWL /root]# ls /
bin dev lib root tmp
boot etc linuxrc sbin usr
copy_lib.sh home mnt sys var
copy_lib.sh~ initrd.img proc temp
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