run u-boot and linux on arm integratorcp qemu

deadlylight

                在qemu上面练习embeded时遇到的一些问题和解决方法
1, 编译
下载binutils-2.18, gcc-4.1.1, uClibc-0.9.29, linux-2.6.25, busybox-1.9.0
编译binutils: configure --prefix=/usr/cross --target=arm-linux
编译gcc，由于arm integragorcp 在qemu上面是没有fpu的，所以要用soft float，但是默认编译soft float会出错，需要应用一个patch
               
               
                --- gcc-4.1.1/gcc/config/arm/t-linux    2006-12-08 15:18:33.000000000 -0800
+++ gcc-4.1.1/gcc/config/arm/t-linux    2006-12-08 15:18:33.000000000 -0800
@@ -4,7 +4,10 @@
LIBGCC2_DEBUG_CFLAGS = -g0
LIB1ASMSRC = arm/lib1funcs.asm
-LIB1ASMFUNCS = _udivsi3 _divsi3 _umodsi3 _modsi3 _dvmd_lnx
+LIB1ASMFUNCS = _udivsi3 _divsi3 _umodsi3 _modsi3 _dvmd_lnx \
+      _negdf2 _addsubdf3 _muldivdf3 _cmpdf2 _unorddf2 _fixdfsi _fixunsdfsi \
+      _truncdfsf2 _negsf2 _addsubsf3 _muldivsf3 _cmpsf2 _unordsf2 \
+      _fixsfsi _fixunssfsi _floatdidf _floatundidf _floatdisf _floatundisf
# MULTILIB_OPTIONS = mhard-float/msoft-float
# MULTILIB_DIRNAMES = hard-float soft-float
--- gcc-4.1.1/gcc/config/arm/linux-elf.h        2006-12-08 15:18:33.000000000 -0800
+++ gcc-4.1.1/gcc/config/arm/linux-elf.h        2006-12-08 15:18:33.000000000 -0800
@@ -63,7 +63,7 @@
    %{shared:-lc} \
    %{!shared:%{profile:-lc_p}%{!profile:-lc}}"
-#define LIBGCC_SPEC "%{msoft-float:-lfloat} %{mfloat-abi=soft*:-lfloat} -lgcc"
+#define LIBGCC_SPEC "-lgcc"
#define GLIBC_DYNAMIC_LINKER "/lib/ld-linux.so.2
然后就可以configure --target=arm-linux --prefix=/usr/cross --disable-shared --with-gnu-as --with-gnu-ld --disable-multilib --disable-threads --disable-tls --disable-nls --disable-libada --disable-libssp --disable-libmudflap --enable-languages=c --with-float=soft
很多选项要disable因为这时候还没有arm的libc，等libc出来以后，还要再次编gcc
编kernel
General setup里面一定要选Initial RAM filesystem
System type里面ARM system type选Integrator
  Integrator Options选Support Integrator/CP platform
  选上Support ARM926T processor
Kernel Features选Use the ARM EABI to compile the kernel
Floating point emulation里面必须至少选一个，这个是kernel的soft float
Device Driver里面Character devices/Serial drivers选上
    ARM AMBA PL011 serial port support
    Support for console on AMBA serial port
  Graphics support/Support for frame buffer devices要选上
  Graphics support/Console display driver support里面要去掉VGA text console，选上
    Framebuffer Console support
然后把kernel编出来，最后得到arch/arm/boot/zImage
编uclibc，这个容易，在默认配置上有少许修改
Target Architecture: arm
Target ABI: EABI
Target Processor Type: Arm 926T
选上Enable floating point number support
不选Target CPU has a floating point unit (FPU), 因为没有硬件fpu
Linux kernel header location: 指向正确的linux header
Library Installation Options里面uClibc runtime library directory和
  uClibc development environment directory都指向/usr/cross/arm-linux
这样就可以编出libc
有了libc之后，我们重新编gccconfigure --target=arm-linux --prefix=/usr/cross --enable-shared --with-gnu-as --with-gnu-ld --enable-threads --enable-tls --disable-nls --enable-languages=c --with-float=soft
然后编busybox，这个也简单，就不多说了
最后编u-boot，这里也要有一个小小的hack，因为默认的arm integratorcp上面没有支持initrd，所以要手工的加一下，在include/configs/integratorcp.h最后加上
#ifndef CONFIG_INITRD_TAG
#define CONFIG_INITRD_TAG 1
#endif
然后make integratorcp_config && make就得到了u-boot.bin
漏掉了一个，还要编qemu，这个不需要交叉编译，就不说什么了
2，用qemu直接装载kernel和initrd
先要从busybox做一个initrd出来，默认的busybox会装到busybox下面一个叫_install的目录里，进到那个目录，然后把动态链接库copy过来
mkdir -p usr/cross/arm-linux/lib
copy -af /usr/cross/arm-linux/lib/*so* .
不知道gcc或uclibc的bug，还是我的步骤问题，这样做还是不能让程序找到动态库，不过我这里有个work around，在程序需要的位置建立链接ln -sf usr/cross/arm-linux/lib lib
ln -sf lib/ld-uClibc.so.0 lib/ld-linux.so.2
现在库都准备好了，可以制作initrd了find . | cpio --quiet -H newc -o | gzip -9 -n > ../initrd.img
有了kernel和initrd我们就可以启动qemu了
qemu-system-arm -nographic -kernel integrator-ok/zImage -initrd busybox-1.9.0/initrd.img -append "console=ttyAMA0 root=/dev/ram0"
结果如下# qemu-system-arm -nographic -kernel integrator-ok/zImage -initrd busybox-1.9.0/initrd.img -append "console=ttyAMA0 root=/dev/ram0"
Uncompressing Linux................................................................... done, booting the kernel.
11initrd start 0
Linux version 2.6.25 (root@yunfchen-lin) (gcc version 4.1.1) #8 Sun Sep 28 21:46:47 CST 2008
CPU: ARM926EJ-S [41069265] revision 5 (ARMv5TEJ), cr=00093177
Machine: ARM-IntegratorCP
Memory policy: ECC disabled, Data cache writeback
CPU0: D VIVT write-through cache
CPU0: I cache: 4096 bytes, associativity 4, 32 byte lines, 32 sets
CPU0: D cache: 65536 bytes, associativity 4, 32 byte lines, 512 sets
Built 1 zonelists in Zone order, mobility grouping on.  Total pages: 32512
Kernel command line: console=ttyAMA0 root=/dev/ram0
PID hash table entries: 512 (order: 9, 2048 bytes)
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3，在qemu里面用u-boot
因为qemu模拟integratorcp的时候没有flash,所以我们只能用-kernel参数来启动qemu
qemu-system-arm -nographic -kernel integrator-ok/u-boot.bin
这样虽然启动了u-boot，但是没有办法加载kernel不过幸好qemu和u-boot都支持网络，那就通过网络直接把kernel加载到内存里面然后再让u-boot找到kernel咯，要做到这点需要你的主机打开dhcp server和tftp server然后加载tun设备，注意把dhcp server bind到tun设备上面
还有一个步骤，要把kernel和initrd转换成u-boot设别的格式，这要用到u-boot的一个工具mkimage，可以在u-boot的目录tools/mkimage找到它，然后要做的就是转换kernel和initrd的格式mkimage -A arm -O linux -T ramdisk -n "arm linux integratorcp initrd" -d initrd.img uinitrd.img.integratorcp
mkimage -A arm
-O linux
-T kernel
-n "arm linux integratorcp
kernel" -d zImage uImage.integratorcp
上面几个步骤完成以后，就可以做我们的最后一步了，真正的用u-boot在qemu里面装载kernel和initrd
qemu-system-arm -nographic -net nic,vlan=0 -net tap,vlan=0,script=no,ifname=tap0 -kernel integrator-ok/u-boot.bin
U-Boot 1.3.4 (Sep 29 2010 - 09:27:30)
DRAM:  128 MB
Flash:  0 kB
*** Warning - bad CRC, using default environment
In:    serial
Out:   serial
Err:   serial
Hit any key to stop autoboot:  0
Integrator-CP # setenv bootargs root=/dev/ram0 mem=128M console=ttyAMA0
Integrator-CP # dhcp; tftp 0x100000 192.168.2.1:uImage.integratorcp; tftp 0x800000 192.168.2.1:uinitrd.img.integratorcp; bootm 0x100000 0x800000
SMC91111: PHY auto-negotiate timed out
Using MAC Address 52:54:00:12:34:56
BOOTP broadcast 1
DHCP client bound to address 192.168.2.154
TFTP from server 192.168.2.1; our IP address is 192.168.2.154
Filename '/tftpboot/pxelinux.0'.
Load address: 0x7fc0
Loading: #
done
Bytes transferred = 14176 (3760 hex)
SMC91111: PHY auto-negotiate timed out
Using MAC Address 52:54:00:12:34:56
TFTP from server 192.168.2.1; our IP address is 192.168.2.154
Filename 'uImage.integratorcp'.
Load address: 0x100000
Loading: #################################################################
         ########
done
Bytes transferred = 1059568 (102af0 hex)
SMC91111: PHY auto-negotiate timed out
Using MAC Address 52:54:00:12:34:56
TFTP from server 192.168.2.1; our IP address is 192.168.2.154
Filename 'uinitrd.img.integratorcp'.
Load address: 0x800000
Loading: #########################################
done
Bytes transferred = 597255 (91d07 hex)
## Booting kernel from Legacy Image at 00100000 ...
   Image Name:
   Image Type:   ARM Linux Kernel Image (uncompressed)
   Data Size:    1059504 Bytes =  1 MB
   Load Address: 00400000
   Entry Point:  00400000
   Loading Kernel Image ... OK
OK
## Loading init Ramdisk from Legacy Image at 00800000 ...
   Image Name:   arm linux integratorcp
   Image Type:   ARM Linux RAMDisk Image (gzip compressed)
   Data Size:    597191 Bytes = 583.2 kB
   Load Address: 00000000
   Entry Point:  00000000
Starting kernel ...
Uncompressing Linux................................................................... done, booting the kernel.
11initrd start 0
Linux version 2.6.25 (root@yunfchen-lin) (gcc version 4.1.1) #8 Sun Sep 28 21:46:47 CST 2008
CPU: ARM926EJ-S [41069265] revision 5 (ARMv5TEJ), cr=00093177
Machine: ARM-IntegratorCP
Memory policy: ECC disabled, Data cache writeback
CPU0: D VIVT write-through cache
CPU0: I cache: 4096 bytes, associativity 4, 32 byte lines, 32 sets
CPU0: D cache: 65536 bytes, associativity 4, 32 byte lines, 512 sets
Built 1 zonelists in Zone order, mobility grouping on.  Total pages: 32512
Kernel command line: root=/dev/ram0 mem=128M console=ttyAMA0
PID hash table entries: 512 (order: 9, 2048 bytes)
Console: colour dummy device 80x30
initrd start c0800040
Dentry cache hash table entries: 16384 (order: 4, 65536 bytes)


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