WhyCan Forum(哇酷开发者社区)

请问我在开启ssh服务后， 使用USB启动荔枝派zero可以正常启动系统， 也可以正常ping通网络。

Welcome to Buildroot
buildroot login: root
Password:
[    5.207448] dwmac-sun8i 1c30000.ethernet eth0: Link is Up - 100Mbps/Full - flow control off

# vi /etc/resolv.conf
# ping www.baidu.com
PING www.baidu.com (14.119.104.189): 56 data bytes
64 bytes from 14.119.104.189: seq=0 ttl=55 time=39.732 ms
64 bytes from 14.119.104.189: seq=1 ttl=55 time=39.354 ms
64 bytes from 14.119.104.189: seq=2 ttl=55 time=39.130 ms
64 bytes from 14.119.104.189: seq=3 ttl=55 time=39.163 ms
64 bytes from 14.119.104.189: seq=4 ttl=55 time=39.092 ms
64 bytes from 14.119.104.189: seq=5 ttl=55 time=39.569 ms
64 bytes from 14.119.104.189: seq=6 ttl=55 time=39.060 ms
64 bytes from 14.119.104.189: seq=7 ttl=55 time=39.144 ms
^C
--- www.baidu.com ping statistics ---
8 packets transmitted, 8 packets received, 0% packet loss
round-trip min/avg/max = 39.060/39.280/39.732 ms

但是我在用外部5V电源供电的时候，系统启动时会卡在buildroot login: root登录命令行，然后就加载不了系统了。

Starting syslogd: OK
Starting klogd: OK
Running sysctl: OK
Initializing random number generator: OK
Saving random seed: OK
Starting network: [    2.063186] sun4i-codec 1c22c00.codec: ASoC: /codec-analog@01c23000 not registered
[    2.070929] sun4i-codec 1c22c00.codec: Failed to register our card
[    2.078996] Generic PHY stmmac-0:01: attached PHY driver [Generic PHY] (mii_bus:phy_addr=stmmac-0:01, irq=-1)
[    2.090945] dwmac-sun8i 1c30000.ethernet eth0: No MAC Management Counters available
[    2.098712] dwmac-sun8i 1c30000.ethernet eth0: PTP not supported by HW
OK

Welcome to Buildroot
buildroot login: root
[  176.087006] random: crng init done

麻烦各位同志帮我解答一下是何原因？