buyed a MSI K9AGM4 mainboard with AMD SB600 chipset. (i have
given up on the via machine)

ethernet and graphics (vesa) works fine but here are problems
with the ata/sata. (not again :-( )

normal ata isnt detected at all, just sata. (not important for me)

here is an BIOS option called "RaidMode" that can be set to IDE, RAID or AHCI,
but seems to make no difference.

plan9 detects the sb600 ahci ok.

#S/sdE: ahci sb600 port 0xe0002800: sss 0 ncs 31 coal 1 mports 3 led 1 clo 1 ems 0
#S/sdE: sb600: sata-II with 4 ports

but doing any io gives me errors. I can reproduce it with any sata
drive i plug in. (hotplug works, really nice)

sdE1: i/o error 50 @5,738
sdE1: LLBA 312,581,808 secstore
ST3160211AS 3AAE 6PT1Q4EP

I tested with dd, with varying block sizes.
the errors happen both on read and on write.
I'v just tested one drive at a time.

i use a recent (pulled the source and recompiled some
days ago) 9pcf kernel booted over pxe.

any suggestions how to debug this?