Chinaunix
标题:
构建嵌入式Linux根文件系统
[打印本页]
作者:
daphne310
时间:
2009-07-02 11:58
标题:
构建嵌入式Linux根文件系统
构建嵌入式Linux根文件系统
移植好了UBOOT和内核之后,便是构建linux根文件系统了。以
http://blog.chinaunix.net/u1/34474/showart_485837.html
文章为基础进行修改。
1)创建根文件系统的基本目录结构。
我把这个过程做成了shell脚本(文件名为mkroot) ,很方便!
#! /bin/sh
echo "creatint rootfs dir......"
mkdir rootfs
cd rootfs
echo "making dir : bin dev etc lib proc sbin sys usr"
mkdir bin dev etc lib proc sbin sys usr #必备的8个目录
mkdir usr/bin usr/lib usr/sbin lib/modules
# Don't use mknod ,unless you run this Script as root !
# mknod -m 600 dev/console c 5 1
# mknod -m 666 dev/null c 1 3
echo
"making dir : mnt tmp var"
mkdir mnt tmp var
chmod 1777 tmp
mkdir mnt/etc mnt/jffs2 mnt/yaffs mnt/data mnt/temp
mkdir var/lib var/lock var/log var/run var/tmp
chmod 1777 var/tmp
echo
"making dir : home root boot"
mkdir home root boot
echo "done"
在你想要建立根文件系统的地方,运行:
[HongGe@Hzh1024n]$ ./mkroot
creatint rootfs dir......
making dir : bin dev etc lib proc sbin sys usr
making dir : mnt tmp var
making dir : home root boot
done
[HongGe@Hzh1024n]$ cd rootfs/dev/
[
HongGe@Hzh1024n
dev]$ su
口令:
[root@Hzh1024n dev]# mknod -m 600 console c 5 1;mknod -m 666 null c 1 3;exit
exit
[
HongGe@Hzh1024n
dev]$
2)配置、编译和安装Busybox-1.9.0
[HongGe@Hzh1024n source]$ tar -xjvf busybox-1.9.0.tar.bz2
修改Makefile文件:
[
HongGe@Hzh1024n
busybox-1.9.0]$ pwd
/home/work/
hzh1024n
/source/busybox-1.9.0
[
HongGe@Hzh1024n
busybox-1.9.0]$ kwrite Makefile
......(第174行附近)
#
ARCH ?= $(SUBARCH)
#
CROSS_COMPILE ?=
ARCH = arm
CROSS_COMPILE =
/usr/local/arm/3.3.2/bin/arm-linux-
[
HongGe@Hzh1024n
busybox-1.9.0]$ make menuconfig
在原有的基础上修改如下:
Busybox Settings --->
Installation Options --->
Don't use /usr
(/home/work/hzh1024n/rootfs) BusyBox installation prefix
Busybox Library Tuning --->
Support for /etc/networks
Additional editing keys
vi-style line editing commands
(15) History size
History saving
Tab completion
Username completion
Fancy shell prompts
Linux Module Utilities --->
[N] Support version 2.2.x to 2.4.x Linux kernels
Shells --->
--- Ash Shell Options 下的选项全选
[
HongGe@Hzh1024n
busybox-1.9.0]$ make
......
LINK busybox_unstripped
Trying libraries: crypt m
Library crypt is needed
Library m is needed
Final link with: crypt m
[
HongGe@Hzh1024n
busybox-1.9.0]$ make install
3)安装glibc库
在开发板上只需要加载器和动态库,假设要构建的根文件系统目录为/home/work/hzh1024n/rootfs,操作如下:
[HongGe@Hzh1024n
busybox-1.9.0]$ cd /usr/local/arm/3.3.2/arm-linux/lib
[HongGe@Hzh1024n lib
]$ cp *.so* /home/work/hzh1024n/rootfs/lib -d
上面复制的库文件不是每个都会被用到,可以根据应用程序对库的依赖关系保留需要用到的。通过ldd命令可以查看一个程序会用到哪些库,主机自带的ldd命令不能查看交叉编译出来的程序,有以下两种替代方法
。
*如果有uClibc-0.9.28的代码,可以进入utils子目录生成ldd.host工具。
$cd uClibc-0.9.28/utils
$make ldd.host
然后将生成的ldd.host放到主机/usr/local/bin目录下即可
$ldd.host busybox
*也可以使用下面命令
$arm-linux-readelf -a "your binary" | grep "shared"
比如对于动态链接的Busybox,它的库依赖关系如下。
0x00000001 (NEEDED) Shared library: [libcrypt.so.1
]
0x00000001 (NEEDED) Shared library: [
libm.so.6
]
0x00000001 (NEEDED) Shared library: [
libc.so.6
]
4)修改和创建必要的文件。
[
HongGe@Hzh1024n
busybox-1.9.0]$ cp -a examples/bootfloppy/etc/* /home/work/hzh1024n/rootfs/etc/
[
HongGe@Hzh1024n
busybox-1.9.0]$ cd /home/work/hzh1024n/rootfs/etc/
1、增加为SHELL导入全局变量的文件/etc/profile
[
HongGe@Hzh1024n
etc]$ kwrite profile
# /etc/profile: system-wide .profile file for the Bourne shells
echo
echo "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"
PATH=/bin:/sbin:/usr/bin:/usr/sbin
export PATH
# Set PS1
#注意:ash 除了SHELL变量外,支持\u、\h、\W、\$、\!、\n、\w 、\nnn(ASCII字符对应的八进制数)
#以及\e[xx;xxm (彩色特效)等等!
#
而且前面还要多加一个
'\'!
echo "Set PS1 in /etc/profile"
export PS1="\\e[05;32m[$USER@\\w\\a]\\$\\e[00;34m"
echo "Done"
echo
2、增加初始化文件
[
HongGe@Hzh1024n
etc]$ kwrite inittab
::sysinit:/etc/init.d/rcS
::restart:/sbin/init
::askfirst:-/bin/sh
::ctrlaltdel:/sbin/reboot
::shutdown:/bin/umount -a -r
::shutdown:/sbin/swapoff -a
[
HongGe@Hzh1024n
etc]$ kwrite fstab
proc /proc proc defaults 0 0
tmpfs /tmp tmpfs defaults 0 0
sysfs /sys sysfs defaults 0 0
tmpfs /dev tmpfs defaults 0 0
3、增加初始化脚本
[
HongGe@Hzh1024n
etc]$ kwrite init.d/rcS
#! /bin/sh
ifconfig eth0 192.168.1.67
echo "----------mount all"
/bin/mount -a
/bin/mkdir /dev/pts
echo "----------Starting mdev......"
/bin/mount -t devpts devpts /dev/pts
/bin/echo /sbin/mdev > /proc/sys/kernel/hotplug
mdev -s
echo "*********************************************************"
echo " HongGe Hzh1024n rootfs "
echo " Wellcome ! ! "
echo "********************************************************"
4
、删除备份文件
[
HongGe@Hzh1024n
etc]$ rm *~ init.d/*~
5、为mdev创建配置文件
[
HongGe@Hzh1024n
etc]$ vi mdev.conf
创建一个mdev.conf文件,内容可有可无。
到此为止一个基本的根文件系统已经制作成功,下一步是挂载jffs2根文件系统。
如果要以挂载JFFS2格式的根文件系统,其基本方法就是将这个建立好的根文件系统制作成jffs2镜像,烧到FLASH中,改改Linux的启动参数即可。
具体做法如下:
一、宿主机HOST编译制做MTD工具
从
http://www.linux-mtd.infradead.org/
下载mtd-utils 的tarball,可以下载最新的。然后解压,并在其目录下 make 就好!
二、制作根文件系统的JFFS2镜像。
使用MTD工具中的mkfs.jffs2命令,具体做法如下:
mkfs.jffs2 -r /home/work/
hzh1024n
/rootfs -o rootfs.jffs2 -e 0x4000 --pad=0x500000 -s 0x200 -n
各参数的意义:
(1)-r : 指定要做成image的源資料夾.
(2)-o : 指定輸出image檔案的文件名.
(3)-e : 每一塊要抹除的block size,預設是64KB.
要注意,不同的flash, 其block size會不一樣.
我的是三星的K9F1208U0B.
(4)--pad (-p): 用16進制來表示所要輸出檔案的大小,也就是root.jffs2的size。很重要的是, 為了不浪費flash空間, 這個值最好符合flash driver所規劃的區塊大小.以我的板子來說,就是5MB.
(5)如果挂载后会出现类似:CLEANMARKER node found at 0x0042c000 has totlen 0xc != normal 0x0 的警告,则加上 -n 就会消失。
(6) 还有的选项,自己看帮助!-h
三、烧写JFFS2镜像到NAND FLASH。
将 rootfs.jffs2烧写到FLASH中,注意内核挂载文件系统的参数,按照参数把文件系统烧写到相关的位置当中。然后启动开发板。
Uncompressing Linux........................................................................................................ done, booting the kernel.
Linux version 2.6.22.6 (HongGe
[email=HongGe@Hzh1024n]
@Hzh1024n
[/email]
) (gcc version 3.3.2) #1 Wed Feb 07 11:18:36 CST 2008
CPU: ARM920T [41129200] revision 0 (ARMv4T), cr=c0007177
Machine: Hzh1024n
Memory policy: ECC disabled, Data cache writeback
CPU S3C2440A (id 0x32440001)
S3C244X: core 405.000 MHz, memory 101.250 MHz, peripheral 50.625 MHz
S3C24XX Clocks, (c) 2004 Simtec Electronics
CLOCK: Slow mode (1.500 MHz), fast, MPLL on, UPLL on
CPU0: D VIVT write-back cache
CPU0: I cache: 16384 bytes, associativity 64, 32 byte lines, 8 sets
CPU0: D cache: 16384 bytes, associativity 64, 32 byte lines, 8 sets
Built 1 zonelists in Zone order, mobility grouping on. Total pages: 16256
Kernel command line: noinitrd root=/dev/mtdblock4 rootfstype=jffs2 rw console=ttySAC0,115200 init=/linuxrc mem=64M
irq: clearing pending ext status 00000200
irq: clearing subpending status 00000003
irq: clearing subpending status 00000002
PID hash table entries: 256 (order: 8, 1024 bytes)
timer tcon=00500000, tcnt a4ca, tcfg 00000200,00000000, usec 00001e57
Console: colour dummy device 80x30
console [ttySAC0] enabled
Dentry cache hash table entries: 8192 (order: 3, 32768 bytes)
Inode-cache hash table entries: 4096 (order: 2, 16384 bytes)
Memory: 64MB = 64MB total
Memory: 61464KB available (2960K code, 306K data, 120K init)
Mount-cache hash table entries: 512
CPU: Testing write buffer coherency: ok
net_namespace: 64 bytes
NET: Registered protocol family 16
S3C2410 Power Management, (c) 2004 Simtec Electronics
S3C2440: Initialising architecture
S3C2440: IRQ Support
S3C2440: Clock Support, DVS off
S3C24XX DMA Driver, (c) 2003-2004,2006 Simtec Electronics
DMA channel 0 at c4800000, irq 33
DMA channel 1 at c4800040, irq 34
DMA channel 2 at c4800080, irq 35
DMA channel 3 at c48000c0, irq 36
usbcore: registered new interface driver usbfs
usbcore: registered new interface driver hub
usbcore: registered new device driver usb
NET: Registered protocol family 2
IP route cache hash table entries: 1024 (order: 0, 4096 bytes)
TCP established hash table entries: 2048 (order: 2, 16384 bytes)
TCP bind hash table entries: 2048 (order: 1, 8192 bytes)
TCP: Hash tables configured (established 2048 bind 2048)
TCP reno registered
NetWinder Floating Point Emulator V0.97 (double precision)
JFFS2 version 2.2. (NAND) ©; 2001-2006 Red Hat, Inc.
fuse init (API version 7.9)
yaffs Feb 15 2008 10:10:34 Installing.
io scheduler noop registered
io scheduler anticipatory registered (default)
io scheduler deadline registered
io scheduler cfq registered
Serial: 8250/16550 driver $Revision: 1.90 $ 4 ports, IRQ sharing enabled
s3c2440-uart.0: s3c2410_serial0 at MMIO 0x50000000 (irq = 70) is a S3C2440
s3c2440-uart.1: s3c2410_serial1 at MMIO 0x50004000 (irq = 73) is a S3C2440
s3c2440-uart.2: s3c2410_serial2 at MMIO 0x50008000 (irq = 76) is a S3C2440
RAMDISK driver initialized: 16 RAM disks of 4096K size 1024 blocksize
loop: module loaded
dm9000 Ethernet Driver
eth0: dm9000 at f6100300,f6100304 IRQ 51 MAC: 08:08:08:08:12:27
Uniform Multi-Platform E-IDE driver Revision: 7.00alpha2
ide: Assuming 50MHz system bus speed for PIO modes; override with idebus=xx
S3C24XX NAND Driver, (c) 2004 Simtec Electronics
s3c2440-nand s3c2440-nand: Tacls=1, 9ns Twrph0=4 39ns, Twrph1=1 9ns
NAND device: Manufacturer ID: 0xec, Chip ID: 0x76 (Samsung NAND 64MiB 3,3V 8-bit)
Scanning device for bad blocks
Bad eraseblock 3579 at 0x037ec000
Creating 7 MTD partitions on "NAND 64MiB 3,3V 8-bit":
0x00000000-0x00020000 : "U-Boot-1.2.0"
0x00020000-0x00030000 : "U-Boot-1.2.0 Parameter"
0x00030000-0x00500000 : "Linux2.6.22.6 Kernel"
0x00500000-0x00a00000 : "Root(cramfs)"
0x00a00000-0x00f00000 :
"
Root(JFFS2)"
0x00f00000-0x01400000 : "Root(YAFFS)"
0x01400000-0x04000000 : "DATA"
usbmon: debugfs is not available
s3c2410-ohci s3c2410-ohci: S3C24XX OHCI
s3c2410-ohci s3c2410-ohci: new USB bus registered, assigned bus number 1
s3c2410-ohci s3c2410-ohci: irq 42, io mem 0x49000000
usb usb1: configuration #1 chosen from 1 choice
hub 1-0:1.0: USB hub found
hub 1-0:1.0: 2 ports detected
mice: PS/2 mouse device common for all mice
S3C24XX RTC, (c) 2004,2006 Simtec Electronics
s3c2410-rtc s3c2410-rtc: rtc disabled, re-enabling
s3c2410-rtc s3c2410-rtc: rtc core: registered s3c as rtc0
s3c2440-i2c s3c2440-i2c: slave address 0x10
s3c2440-i2c s3c2440-i2c: bus frequency set to 98 KHz
s3c2440-i2c s3c2440-i2c: i2c-0: S3C I2C adapter
S3C2410 Watchdog Timer, (c) 2004 Simtec Electronics
s3c2410-wdt s3c2410-wdt: watchdog inactive, reset disabled, irq enabled
TCP cubic registered
NET: Registered protocol family 1
RPC: Registered udp transport module.
RPC: Registered tcp transport module.
s3c2410-rtc s3c2410-rtc: setting system clock to 2008-02-17 12:46:08 UTC (1203252368)
VFS: Mounted root (jffs2 filesystem).
Freeing init memory: 120K
init started: BusyBox v1.9.1 (2008-02-16 15:04:08 CST)
starting pid 779, tty '': '/etc/init.d/rcS'
----------mount all
----------Starting mdev......
*********************************************************
HongGe Hzh1024n rootfs
Wellcome ! !
********************************************************
starting pid 783, tty '': '/bin/login'
(none) login: root
Password:
login[783]: root login on 'console'
Processing /etc/profile...
Set search library path in /etc/profile
Set user path in /etc/profile
Set PS1 in /etc/profile
Done
[root@~]#
成功!!!
本文来自ChinaUnix博客,如果查看原文请点:
http://blog.chinaunix.net/u3/100156/showart_1983691.html
欢迎光临 Chinaunix (http://bbs.chinaunix.net/)
Powered by Discuz! X3.2