Subject: MPC8260 fcc_enet transmit timed out

From: hubert loewenguth <[email-masked]>
Date: Mon, 14 Nov 2005 18:34:32 +0100

Hello to the community

After having searched more than a week to correct my problem, I have 
finally decided to try to find some help :

- I have a board with a MPC8260 (HIP 3 C.2), with three PHY chipset : 
LXT971A from intel
- The MII  lines MDC and MDIO are present, but I have no PHY interrupt line
=> so I have to configure my PHY and the fcc_enet.c drivers to be in 
half-duplex mode
- I use the 2.4.20 linux kernel

Every thing works very fine, everything is ok and the TCP/IP ethernet 
communication works fine (telnet, ftp, udp ....)
BUT if I plug / unplug the ethernet link numerous times during TCP 
traffic,the  fcc_enet.c driver enter in an "infernal loop" and prints 
continuously :

/NETDEV WATCHDOG: eth0: transmit timed out
eth0: transmit timed out.
 Ring data dump: cur_tx c02b60b8 (full) cur_rx c02b7098.
 Tx @base c02b60a0 :
1c00 05ea 014f786a
1c00 05ea 013ce06a
1c00 05ea 013ce86a
........
/
And never exit from this infernal loop.

I have found some personns in this mailling list who has encounter a 
problem wich seems similar:

http://ozlabs.org/pipermail/linuxppc-embedded/2005-January/016539.html
http://ozlabs.org/pipermail/linuxppc-embedded/2001-December/005714.html

I really don't find what can be the origin of my problem:
- I don't succeed to reproduce it in full duplex mode (using a full 
duplex link and configuring the drivers and the PHY in full duplex)
- I have verified the pin configuration numerous times, the routing of 
clock signals also....
- I have not  applied  a MPC8260  microcode patch, I will try it but I 
don't think there is a patch wich correct it

Is there any personn who has already encounter this matter ?
Thanks to the community for any help