I.MX6 U-Boot ping网络

/*********************************************************************
 *                       I.MX6 U-Boot ping网络
 * 说明：
 *     百兆网络是可以，千兆网络数据发送不出去，看一下U-Boot千兆网络是否
 * 正常，问题同样存在。
 *  
 *                               2017-4-12 深圳 龙华民治樟坑村 曾剑锋
 ********************************************************************/

操作及数据输出如下：
    => setenv etnaddr 7C:CB:E2:E0:28:07
    => setenv ipaddr 10.10.10.10
    => setenv serverip 10.10.10.15
    => setenv gatewayip 10.10.10.1
    => setenv netmask 255.255.255.0
    => ping 10.10.10.15
    Using FEC device
    
    ARP Retry count exceeded; starting again
    
    ARP Retry count exceeded; starting again
    ...
    ARP Retry count exceeded; starting again
    FEC Waiting for PHY auto negotiation to complete..... done
    
    ARP Retry count exceeded; starting again
    
    ARP Retry count exceeded; starting again
    
    ARP Retry count exceeded; starting again
    
    ARP Retry count exceeded; starting again
    host 10.10.10.15 is alive
    => ping 10.10.10.15
    Using FEC device
    host 10.10.10.15 is alive
    => ping 10.10.10.15
    Using FEC device
    host 10.10.10.15 is alive
    => ping 10.10.10.15
    Using FEC device
    host 10.10.10.15 is alive
    => ping 10.10.10.15
    Using FEC device
    
    ARP Retry count exceeded; starting again
    ...