mcp55 forcedeth woes

["Yan Seiner" <yan@seiner.com>]

I have a few Asus M2N-SLI deluxe mobos.  These mobos have the MCP55
chipset and two 1gb ethernet ports.  Occasionally, and for no reason that
I can figure out, these ports will die.  There are various ways to try and
fix these; they seem to be about 50% effective, and approach something
akin to voodoo.

Based on this discussion here:

http://patchwork.kernel.org/patch/16212/

I've gotten the ability to turn the ports on and off somewhat.

For port 0,

ethtool -s eth0 autoneg off speed 10 duplex full

turns on the link, and gets me half-duplex, 10mb/sec. Not much, granted.

ethtool -s eth0 autoneg off speed 100 duplex full

causes the link to go up and down on about a 2 second cycle.

ethtool -s eth0 autoneg on

causes the link to drop.

For port 1, the behavior is similar, except that I can get a stable 100
mbit connection.

So the problem is in the autoneg code. It's a driver issue as this is
reported widely to work under windows of various flavors.

I'm running 2.6.29.1; I'm ok with patching and building kernels, but I'm
not a kernel hacker.

What, if anything, can I provide and do to fix this?


-- 
Yan Seiner, PE

Support my bid for the 4J School Board
http://www.seiner.com