使用zc706板卡调试uboot，选用sd卡启动，烧入自己生成的boot文件，出现
missing environment variable: bootfile
Retrieving file: pxelinux.cfg/default-arm-zynq
ethernet@e000b000 Waiting for PHY auto negotiation to complete......... TIMEOUT !
missing environment variable: bootfile
Retrieving file: pxelinux.cfg/default-arm
ethernet@e000b000 Waiting for PHY auto negotiation to complete......... TIMEOUT !
missing environment variable: bootfile
Retrieving file: pxelinux.cfg/default
ethernet@e000b000 Waiting for PHY auto negotiation to complete......... TIMEOUT !
Config file not found
ethernet@e000b000 Waiting for PHY auto negotiation to complete......... TIMEOUT !@
ethernet@e000b000 Waiting for PHY auto negotiation to complete......... TIMEOUT !
Zynq>
Zynq>
请问是什么问题
说明uboot中phy芯片的驱动没有正常工作，网口不能正常通讯！