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//By:yuyongbao
//QQ:673360056
//平台powerpc mpc8379e linux 2.6.22
１、先用fdisk 给SD卡分区，用作文件系统。
将读卡器插入PC机虚拟机，在PC机上执行fdisk /dev/sdb
选择n 。。。。。。。。步骤与硬盘分区一致。
２、用mkfs.ext3格式化SD卡的一个分区mke2fs /dev/sdb1 (比如分区1)
３、将SD卡挂载mount –t ext3 /dev/sdb1 /home/nfs ，然后将文件系统拷贝进去。
４、 设置u-boot参数。bootargs=root=b301 rw console=ttyS0,115200 rootdelay=5(或setenv bootargs root=/dev/mmcblk0p1 rw console=ttyS0,115200 rootdelay=5)
启动信息见《从SD启动完整信息》
启动信息(可能还有一小部分错误)
//
U-Boot 1.3.0-rc2 (Apr 24 2008 - 01:32:37) MPC83XX
Reset Status:
CPU: e300c4, MPC8379E, Rev: 10 at 528 MHz, CSB: 264 MHz
Arbiter Configuration Register (ACR): 0x00030300
System Priority Configuration Register (SPCR): 0x00400300
System Clock Configuration Register (SCCR): 0x5fffff55
Board: Ehometech MPC837xE
I2C: ready
DRAM: 256 MB
FLASH: 8 MB
Ehometech NAND: 1024 MiB
In: serial
Out: serial
Err: serial
Net: TSEC0, TSEC1
Hit any key to stop autoboot: 0
Ehometech# setenv bootargs root=b301 rw console=ttyS0,115200 rootdelay=5
Ehometech# saveenv
Saving Environment to Flash...
Un-Protected 1 sectors
Erasing Flash...
. done
Erased 1 sectors
Writing to Flash... done
Protected 1 sectors
Ehometech# printenv
ramboot=setenv bootargs root=/dev/ram rw console=$consoledev,$baudrate $othbootargs;tftp $ramdiskaddr $ramdiskfile;tftp $loa