inquiry data fails comparison at DV1 step

[Rong-en Fan]

I reported this to scottl@ some time ago. I think
it may be better to post it here.

I have a system running i386 7-CURRENT as of today.
An external raid connected to a Adaptec 29160, but it
is only running at 6.6MB/s. relevant dmesg are:

ahc0: <Adaptec 29160 Ultra160 SCSI adapter> port 0x2500-0x25ff mem
0xfbfdf000-0xfbfdffff irq 18 at device 2.0 on pci1
ahc0: [ITHREAD]
(probe2:ahc0:0:0:0): inquiry data fails comparison at DV1 step
(probe2:ahc0:0:0:0): inquiry data fails comparison at DV1 step
(probe2:ahc0:0:0:0): inquiry data fails comparison at DV1 step
(probe2:ahc0:0:0:0): inquiry data fails comparison at DV1 step
(probe2:ahc0:0:0:0): inquiry data fails comparison at DV1 step
da2 at ahc0 bus 0 target 0 lun 0
da2: <IFT IFT-7200 0145> Fixed Direct Access SCSI-4 device
da2: 6.600MB/s transfers (16bit)
da2: Command Queueing Enabled
da2: 915737MB (1875429888 512 byte sectors: 255H 63S/T 116740C)

This card and the raid box work perfectly with 6-STABLE.
I heard from Scott that making DV work is really tricky and
not that easy. I would like to help to test any patches.
Or is there any workaround to this problem?

Regards,
Rong-En Fan