/*********************************************************************

 *                       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::

    => 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

    ...