Re: [RFC PATCH] irq: handle private interrupt registration

Thomas Gleixner
2010-06-02T13:08:26Z

On Wed, 2 Jun 2010, Felipe Balbi wrote:

> Hi,
>
> On Wed, Jun 02, 2010 at 01:14:32AM +0200, ext Thomas Gleixner wrote:
> > 1) Use PER_CPU offsets for the irq numbers. The generic irq code does
> > not care whether the interrupt number is matching any physical
> > numbering scheme in the hardware, as long as the arch specific chip
> > implementation knows how to deal with it, which is not rocket
> > science to do.
>
> FWIW, I think (1) is a better approach as the problem will vanish altogether
> and to me it sounds like the simpler approach as well. Archs which have more
> than one IRQ chip (like OMAP with the twl4030 family) will already use
> sequencial numbering anyway, so using the same approach for N cpus, to me,
> sounds like a good deal.
>
> While at that, a question from my side: do we have a generic way of fetching
> the last IRQ number so we can easily use that to calculate the physical number
> of the IRQ line on the chip ?
>
> On OMAP, we have been passing that number down to twl4030 via platform_data,
> but it would be better to ask genirq to tell us which was the last irq number
> "claimed".

No, we don't, but it might be a good idea to move the virq management
from powerpc into generic code so other archs can use it as
well. Needs some thought.

Thanks

tglx