DM385 uboot 下载到内存，go之后就卡住

Filename 'u-boot.bin'.
Load address: 0x81000000
Loading: #######################################
done
Bytes transferred = 195884 (2fd2c hex)
DM388_IPNC#go  0x81000000
## Starting application at 0x81000000 ...

不知是何原因吗，请指教