Re: linux-2.6.10, ppc8280, odd ARP request - solved
From: Richard Danter <hidden>
Date: 2005-05-12 11:31:54
Richard Danter wrote:
My board boots using U-Boot. It tftp loads the kernel image via FCC2, so I know the FCC's are working (I have tested the others too). This part is fine, but once the kernel has loaded it tries to NFS mount the root filesystem. When it gets to the point of looking up the RPC port it first sends an ARP request for the server. When eth0 is any of the FCC's I see a 59 byte packet on the wire (using ethereal). The server either does not see the packet or just ignores it so there is no reply to the board. When I boot using SCC1 as eth0 the ARP request sent is 60 bytes long. It is replied to and the NFS mount works. I noticed that U-Boot also sends an ARP request before the tftp download starts and it is 60 bytes long using both SCC and FCC ports. But as far as I know, ARP requests can be varying length (the last few bytes seem to be just padding).
Looks like the problem may be with the setup of the FCC, particularly with working out what speed to run at. I connected my board to a 100BaseT hub and it worked perfectly. It was failing when I was using an older 10BaseT hub. In both cases the hub is a Netgear and I have never had a problem with any other board or PC. Odd how it effects Linux but not U-Boot. Seems to indicate a driver issue anyway. Rich