>>>>> "Manuel" == Manuel Bouyer <bouyer@antioche.lip6.fr> writes:

    Manuel> Testers, please report me the 'conf =' line printed after
    Manuel> disks probe, if you can catch it; and also which modes are
    Manuel> used for the drives (or the whole dmesg if you fear to
    Manuel> forget something :)

On my tibook I get the following wdc related output:
(netbooting is a great tool for this)

  wdc0 at obio0 offset 0x1f000 irq 19: DMA transfer
  wd0 at wdc0 channel 0 drive 0: <IBM-DJSA-220>
  wd0: drive supports 16-sector PIO transfers, LBA addressing
  wd0: 19077 MB, 16383 cyl, 16 head, 63 sec, 512 bytes/sect x 39070080 sectors
  wd0: drive supports PIO mode 4, DMA mode 2, Ultra-DMA mode 4 (Ultra/66)
  conf = 0x11823, cyc = 4 (120 ns), act = 3 (70 ns), inact = 1
  wd0(wdc0:0:0): using PIO mode 4, DMA mode 2, Ultra-DMA mode 4 (Ultra/66) (using DMA data transfers)
  wdc1 at obio0 offset 0x20000 irq 20: DMA transfer
  atapibus0 at wdc1 channel 0: 2 targets
  cd0 at atapibus0 drive 0: <MATSHITADVD-ROM SR-8187, , HA15> type 5 cdrom removable
  cd0: drive supports PIO mode 4, DMA mode 2, Ultra-DMA mode 2 (Ultra/33)
  conf = 0x11823, cyc = 4 (120 ns), act = 3 (70 ns), inact = 1
  cd0(wdc1:0:0): using PIO mode 4, DMA mode 2 (using DMA data transfers)
  wdc2 at obio0 offset 0x21000 irq 21: DMA transfer

Trying to access the disk still ends up with:

  wdc0:0:0: lost interrupt
        type: ata tc_bcount: 512 tc_skip: 0
  [...]

Markus.