>Anyone got any ideas on what is actually wrong (why it doesn't work
>at a different IO address) and how to fix it properly?

The code that allocates I/O and memory address spaces for CardBus seems
rather ... strange.  I noticed two problems when I was debugging a similar
problem:

- The addresses are chosen arbitrarily (well, okay, they're chosen
  arbitrarily for PCMCIA, but somehow the default for PCMCIA seem
  to be "better" in many cases).
- A extremely large alignment is specified when allocating stuff for
  Cardbus.

I think it's the second thing that makes my CD-ROM drive not work (since
that driver needs to allocate two chunks of space).

I didn't know there is an extent provided for this purpose by the
PCIBIOS, though ...

--Ken