Re: [linux-audio-user] Setting IRQ on intel8x0-card

From: Paul Davis <paul@email-addr-hidden>
Date: Mon Oct 09 2006 - 22:27:58 EEST

On Mon, 2006-10-09 at 15:07 -0400, Lee Revell wrote:
> On Mon, 2006-10-09 at 14:46 -0400, Paul Davis wrote:
> > its basically not possible. PC architecture has changed quite a lot in
> > the last few years, and AFAIK you can no longer get the kernel to change
> > IRQ assignments. it seems stupid, i know, but i dug into this rather
> > deeply a year or so back, and basically the kernel picks up the IO-APIC
> > routings and does not modify them, even with the many flags that appear
> > to be related to possibly modifying them :( there is a really cool perl
> > script that actually analyses IO-APIC routings via the /proc filesystem,
> > and it confirmed for me what i was worried about.
> >
> > if your BIOS doesn't allow it, you're out of luck *AFAIK*. if i am
> > wrong, i will be happy to hear more, since i face similar issues on my
> > laptop.
>
> Has it ever been possible to change the IRQs of onboard devices? I
> thought it was hard wired.

the wiring into the IO-APIC is board-level, but the IO-APIC is
programmable and thus you can change the actual IRQ that the device
generates, in theory.

however, the kernel at this time doesn't contain code that tries to
reprogram the IO-APIC in this area of its function, so you get what it
gives you.

i believe.
Received on Tue Oct 10 00:15:02 2006

This archive was generated by hypermail 2.1.8 : Tue Oct 10 2006 - 00:15:02 EEST