7.0-CURRENT MCP55 PATA to SATA convertor problems on Asus M2N32 WS Pro

Hi,
   Been experimenting with the June snapshot of i386 7.0-CURRENT for some 
weeks now, on an Athlon XP. I had a 3 drive ZFS fs on PATA drives.
   Tried to move my installation to an Asus M2N32 WS Pro motherboard based 
system (Nforce 590 SLI). It supports 8 possible drives on the chipset 
2xPATA + 6xSATA, which are reported by 6.2 as these controllers:

atapci0: nVidia nForce MCP55 UDMA133 Controller
atapci1: nVidia nForce MCP55 SATA300 Controller
atapci2: nVidia nForce MCP55 SATA300 Controller
atapci3: nVidia nForce MCP55 SATA300 Controller

   I put the drives onto some PATA-SATA convertors that I had. They have 
always worked before with 6.2. Even though they are connected to SATA 
ports, the 6.2 kernel displays the drive as UDMA100 or such rather than 
SATA150 i.e. it is aware they are PATA drives.
   When 7.0 tries to probe the SATA converted drives connected to the SATA 
controllers it gives the following error, for each drive (after suitable 
timeout):

unknown: timeout waiting to issue command
unknown: error issuing ATA_IDENTIFY command

   After this failed probing, a later hard reset of the PC causes the BIOS 
then to fail to detect any SATA drives. The system needs power cycling 
before the BIOS is happy detecting all drives again. The failed probing of 
7.0 seems to mess the controller up somehow, that even a hard reset 
doesn't fix (which strikes me as unusual).
   7.0 has no problems detecting and identifying the drives when they are 
directly connected to the UDMA133 controller.
   7.0 also has no problems probing a real SATA drive. It seems to be only 
converted drives.
   See boot -v attached.
   This is with both amd64 and i386 7.0-CURRENT June snapshot.
   I've also updated to and rebuilt CURRENT i386 as of today and removed 
all usb modules (just in case), with no improvement in this problem.
   However, 6.2 seems to have no problems with this hardware i.e. it probes 
the converted PATA drives on SATA ports without issue.
   If you need any more info, I'd be glad to provide it.
   Many thanks.

-- 
Mark Powell - UNIX System Administrator - The University of Salford
Information Services Division, Clifford Whitworth Building,
Salford University, Manchester, M5 4WT, UK.
Tel: +44 161 295 4837  Fax: +44 161 295 5888  www.pgp.com for PGP key