> CMD Technology product 0x0680 (miscellaneous mass storage, revision 0x02) at pci
> 2 dev 10 function 0 not configured

With the code from -current this one Just Works.  I didn't apply the
patch mrg posted but did the equivalent thing a few months back, and
then zapped the wrong tree so don't have the precise diff. :-(

NetBSD 1.6.1_RC2 (GENERIC) #1: Mon Mar 17 17:55:50 EST 2003
...
pciide0 at pci1 dev 13 function 0: Silicon Image 0680 (rev. 0x02)
pciide0: bus-master DMA support present
pciide0: primary channel configured to native-PCI mode
pciide0: using irq 9 for native-PCI interrupt
...

Giles