Re: APIC priorities, can they be changed?

From: Florian Schmidt
Date: Fri Feb 16 2007 - 11:18:44 EST

On Thursday 15 February 2007, Mike Panetta wrote:
> I did try that. The BIOS only allows me to either allocate an IRQ to be
> a PCI interrupt, or reserve it (for what I have no idea). The IRQ's
> listed in the BIOS are also different from the ones Linux sees. I think
> the BIOS is seeing the XT-PIC IRQ numbers and Linux is seeing the APIC
> numbers. For example the little bios blurb that prints before the
> system boots says the USB controller I am interested in is
> assigned/using IRQ 10, Linux sees it using IRQ 18.
> I have found that I can keep Linux from using the APIC by disabling it
> with a kernel command line switch, but that does not help, it just makes
> Linux use the XT-PIC instead of the IO-APIC to do IRQ routing.
> So I guess I'm back to my original question of 'Would changing the
> vector numbers do what I want?' and if the answer is 'yes', how would I
> do it?

With XT-PIC, there was a way to change the priotrities used by the IRQ. It was
called irqtune iirc.

Ah ya,

Dunno if there's something similar available for APIC..


Palimm Palimm!
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