Re: Handling interrupt routing cleanly...

[Tarl Neustaedter]

Stefan Reinauer wrote:
> Eric W. Biederman  [040202 01:28]:
> > Thinking about this a little more open firmware defines one
> > single root for it's interrupt tree, even if it must be purely
> > virtual.

I seem to be dropping into this conversation late; What do you
mean that there is a single root for the interrupt tree?

The interrupt-map stuff can point to interrupt owners anywhere
in the tree; The common case I've run into is a system which has
on-board devices with the interrupts routed to an interrupt
controller on a PCI bridge. Since the on-board devices are
frequently either children of a different PCI bus or occasionally
not under a PCI bus at all, we need to use the interrupt-map
property to say "use interrupt #17 under that chip over there".