The whole algorithm was wrong.  What we need to do is:

1) Walk each PCI bus above this device on the path to the
   PCI controller nexus, and for each:
      a) If interrupt-map exists, apply it, record IRQ controller node
      b) Else, swivel interrupt number using PCI_SLOT(), use PCI bus
	 parent OBP node as controller node
      c) Walk up to "controller node" until we hit the first PCI bus
	 in this domain, or "controller node" is the PCI controller
	 OBP node
2) If we walked to PCI controller OBP node, we're done.
3) Else, apply PCI controller interrupt-map to interrupt.

There is some stuff that needs to be checked out for ebus and
isa, but the PCI part is good to go.
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

When crawling up the PCI bus chain, stop at the first node
that has an interrupt-map property before we hit the root.

Also, if we use a bus interrupt-{map,mask} do not forget to
update the 'intmask' pointer as we do for the 'intmap' pointer.
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!