Thanks for the help , i found out that the kernel was not configued well for pci net card .
Now i am boarding U-BOOT and kernel(linuxppc) to my own board (based on MPC5200,have a i82551 on board without EPROM).After i set the eth1addr ,U-boot could tftp files through the i82551 chip : PCI: Bus Dev VenId DevId Class Int 00 18 8086 1209 0200 00 00 1a 1057 5803 0680 00 In: serial Out: serial Err: serial Net: FEC ETHERNET, i82559#0 But after the kernel bootup ,i could not find eth1 ,message during bootup as follow : POSIX conformance testing by UNIFIX PCI: Probing PCI hardware PCI: Cannot allocate resource region 0 of device 00:1a.0 Intel(R) PRO/100 Network Driver - version 2.3.38-k1 Copyright (c) 2004 Intel Corporation PCI: Enabling device 00:18.0 (0006 -> 0007) e100: Invalid Ethernet address e100: Failed to initialize, instance #0 How can i make the chip active ?