RE: interrupts across PCI bridge(s) not handled

From: Charles Martin
Date: Mon Nov 03 2003 - 16:49:26 EST

> Hmm..
> The MP tables mention IRQ's up to 51, but no further.
> But the PIRQ routing tables talk about irqs 92-95 for bus 6.
> It really looks like the IRQ routing entries are just broken. One
> potential fix is to enable ACPI, and hope that the ACPI irq
> routing isn't
> as broken as the PIRQ stuff.
> Other than that I don't see anything we can do. Anybody else?
> Linus

I enabled ACPI, and the interrupts are now assigned correctly,
and in the range of 48-51:


48: 878 389 IO-APIC-level piraq
49: 923 336 IO-APIC-level piraq
50: 17239 838 IO-APIC-level ioc2, piraq
51: 879 404 IO-APIC-level piraq

They are now getting handled properly, i.e. I am receiveing
interrupts from the boards located in the backplane extender.
This is with 2.4.22.

I didn't realize that ACPI is related to interrupt management
as well as power control. Is there any downside to using ACPI?


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