[SGVLUG] More laptop fun--IRQ assignments

[Dustin]

On Thu, 8 Dec 2005, David Lawyer wrote:

That's some fairly amazing research, David.  I haven't responded because I 
didn't have time to dig into it, but I woke up and couldn't sleep, so....

> I just now found this in a hard-to-find HOWTO.  Google's Linux
> search engine can't find it.  It's at:

Yeah, that is hard to find, and surprisingly current.  Thanks.

>    acpi_irq_balance
>           ACPI  will  balance active IRQs to minimize sharing. This is the
>           default in APIC mode.

I tried this, but as it's default in ACPI mode I didn't expect a change.  
There wasn't.

>    acpi_irq_pci=...
>           If  you have set acpi_irq_balance, you have to reserve some IRQs
>           for  for  use  by  PCI  or else ACPI may use them all; list them
>           here. Format: <irq>,<irq>...

This I didn't know about.  Unfortunately, it didn't seem to work, but 
certainly worth a try.

> tell it to balance and it doesn't, there's either a bug in the sw or
> the hardware doesn't have enough pci interrupt traces.

The latter is what I'm afraid of.

Dustin