Re: Is it possible to change IRQ for certain device?

From: Lee Revell
Date: Mon Jan 14 2008 - 01:04:31 EST


On Jan 14, 2008 12:30 AM, Bryan Donlan <bdonlan@xxxxxxxxx> wrote:
>
> On Jan 13, 2008 10:57 PM, Lee Revell <rlrevell@xxxxxxxxxxx> wrote:
> > On Jan 11, 2008 11:57 AM, Jan Marek <linux@xxxxxxxxxxxxx> wrote:
> > Why is a shared IRQ a problem for you? IRQ handlers are supposed to
> > be fast enough that disabling an IRQ line for the duration of the
> > handler execution should not be a problem even if the IRQ is shared.
> > VGA interrupts in particular should only fire once per frame and only
> > need to flip some bits to wake up any processes waiting on vsync.
> >
> > If you have issues with a shared VGA interrupt then the bug is that
> > some IRQ handler runs for too long and should be deferring work to a
> > bottom half.
>
> Jan is apparently using the nvidia binary driver, so I doubt it will
> be possible to fix the bug that prevents it from sharing IRQs.
>

Ah, of course, stupid me. Thought I was on linux-audio-user where
this is a FAQ (for completely different reasons) and not LKML.

But this is strange - I'm sure I've seen people using that driver with
a shared IRQ before.

Jan, maybe you can blacklist ohci-hcd as a workaround? In any case
let's take this discussion off LKML so as not to spam the list with
binary only driver issues.

Lee
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