[PATCH] generic irq subsystem: ppc64 port

[Benjamin Herrenschmidt]

Hi !

That patch will unfortunately break a load of ppc64 boxes.

If you look closely at the ppc64 code, you'll notice we don't
use the irq_desc array directly but go through a get_irq_desc()
accessor. This is because our interrupt numbers can be very
large and scattered, and thus we have a remapping tree.

I still like the idea of the patch, so it would be useful if
you added the possibility for us to just change that behaviour,
that is replace all occursences of irq_descs + i with get_irq_desc()
and provide a generic one that just does that, with a #ifndef so
that the architecture can provide it's own. 

If you agree with the principle, though, I suppose I can do it
and send a proposed patch tomorrow.

Ben.