STMMAC driver:
        platform registration... 
        done!
stmmac_dvr_probe: alloc_etherdev  done!
        eth%d - (dev. name: stmmaceth - id: 0, IRQ #21
        IO base addr: 0xbe800000)
stmmac - user ID: 0x10, Synopsys ID: 0x37
 Ring mode enabled
 DMA HW capability register supported Enhanced/Alternate descriptors
        Enabled extended descriptors
 RX Checksum Offload Engine supported (type 2)
 TX Checksum insertion supported
 Wake-Up On Lan supported
stmmac_dvr_probe: stmmac_hw_init  done!
stmmac: probed
eth0: No PHY found
Initializing UNIMAC ethernet driver.

各位前辈帮忙分析一下原因，不胜感激！