[U-Boot] why I can't run the u-boot from flash?

[Jason.Sun]

I am porting a boot from sequoia.
I have use the BDI3000 to load the u-boot.bin and flash to norflash.
I can trace the codes by BDI3000 and receive the u-boot info from uart as following.
but when I try to power on and run the codes itself but not use BDI3000 to send "go".
there are  not any characters from the uart port.
I have no idea to find the bug. have any one can give some advice?

Jason
 
U-Boot 1.3
CPU:   AMCC PowerPC 440EPx Rev. A at 333.333 MHz (PLB=133, OPB=66, EBC=66 MHz)
       Security/Kasumi support
       Bootstrap Option A - Boot ROM Location EBC (8 bits)
       Internal PCI arbiter enabled, PCI async ext clock used
       32 kB I-Cache 32 kB D-Cache
Board: Sequoia - AMCC PPC440EPx Evaluation Board, Rev. 0, PCI=33 MHz
I2C:   ready
DTT:   1 FAILED INIT
DRAM:  256 MB
FLASH: 64 MB
NAND:  512 MiB
PCI:   Bus Dev VenId DevId Class Int
        00  04  7080  0001  7b20  43
USB:   Host(int phy) Device(ext phy)
Net:   ppc_4xx_eth0, ppc_4xx_eth1
Type run flash_nfs to mount root filesystem over NFS
Hit any key to stop autoboot:  0
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=> printe
bootcmd=run flash_self
bootdelay=5
baudrate=115200
loads_echo=
preboot=echo;echo Type "run flash_nfs" to mount root filesystem over NFS;echo
hostname=sequoia
netdev=eth0
nfsargs=setenv bootargs root=/dev/nfs rw nfsroot=${serverip}:${rootpath}
ramargs=setenv bootargs root=/dev/ram rw
addip=setenv bootargs ${bootargs} ip=${ipaddr}:${serverip}:${gatewayip}:${netmask}:${hostname}:${netdev}:off panic=1
addtty=setenv bootargs ${bootargs} console=ttyS0,${baudrate}
addmisc=setenv bootargs ${bootargs}
initrd_high=30000000
kernel_addr_r=400000
fdt_addr_r=800000
hostname=sequoia
bootfile=sequoia/uImage
rootpath=/opt/eldk/ppc_4xxFP
flash_self=run ramargs addip addtty addmisc;bootm ${kernel_addr} ${ramdisk_addr} ${fdt_addr}
flash_nfs=run nfsargs addip addtty addmisc;bootm ${kernel_addr} - ${fdt_addr}
net_nfs=tftp ${kernel_addr_r} ${bootfile}; tftp ${fdt_addr_r} ${fdt_file}; run nfsargs addip addtty addmisc;bootm ${kernel_addr_r} - ${fdt_addr_r}
fdt_file=sequoia/sequoia.dtb
flash_self_old=run ramargs addip addtty addmisc;bootm ${kernel_addr} ${ramdisk_addr}
flash_nfs_old=run nfsargs addip addtty addmisc;bootm ${kernel_addr}
net_nfs_old=tftp ${kernel_addr_r} ${bootfile};run nfsargs addip addtty addmisc;bootm ${kernel_addr_r}
load=tftp 200000 sequoia/u-boot.bin
update=protect off 0xFFFA0000 FFFFFFFF;era 0xFFFA0000 FFFFFFFF;cp.b ${fileaddr} 0xFFFA0000 ${filesize};setenv filesize;saveenv
upd=run load update
nload=tftp 200000 sequoia/u-boot-nand.bin
nupdate=nand erase 0 100000;nand write 200000 0 100000;setenv filesize;saveenv
nupd=run nload nupdate
kernel_addr=FC000000
ramdisk_addr=FC180000
ethaddr=00:10:EC:00:1D:95
eth1addr=00:10:EC:80:1D:95
ethact=ppc_4xx_eth0
bootargs=root=/dev/ram rw ip=::::sequoia:eth0:off panic=1 console=ttyS0,115200
ipaddr=172.17.25.69
mem=262120k
ver=U-Boot 1.3
Environment size: 1799/8187 bytes
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