Here's my suggested fix...  good catch Ricky.

Yes, unfortunately performance will be dog slow.

Silicon Image 311x is fully SATA compliant -- but it's the only 
controller that sends odd-sized packets to the SATA device.  That causes 
no end of problems, including the thing that SIL_QUIRK_MOD15WRITE 
attempts to work around.

I've got contacts at Silicon Image, and have been meaning to bug them 
for a "real fix" for a while.  It is rumored that there is a much better 
fix, which allows full performance while at the same time not killing 
your SATA drive due to odd-sized SATA frames on the wire.

Unfortunately, at this point in time, we must err on the side of caution 
and cripple performance, for stability.

	Jeff