lkml.org 
[lkml]   [2008]   [Oct]   [6]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [PATCH] x86 ACPI: Blacklist two HP machines with buggy BIOSes (Re: 2.6.27-rc8+ - first impressions)

* Maciej W. Rozycki <macro@linux-mips.org> wrote:

> On Mon, 6 Oct 2008, Ingo Molnar wrote:
>
> > i think it was caused by this stream of IO-APIC changes:
> >
> > 49a66a0: x86: I/O APIC: Always report how the timer has been set up
> > 17c4469: x86: I/O APIC: Include <asm/i8259.h> required by some code
> > 593f4a7: x86: APIC: remove apic_write_around(); use alternatives
> > ce8b06b: x86: I/O APIC: remove an IRQ2-mask hack
> > af17478: x86: I/O APIC: Never configure IRQ2
> > c88ac1d: x86: L-APIC: Always fully configure IRQ0
> > 1baea6e: x86: L-APIC: Set IRQ0 as edge-triggered
> >
> > Rafael/Maciej, which of these is causing it? ce8b06b ("x86: I/O APIC:
> > remove an IRQ2-mask hack")?
>
> None of the above. This:
>
> 691874f: x86: I/O APIC: timer through 8259A second-chance
>
> This change has fixed a problem with the timer for a lot of systems
> and permitted the removal of a bunch of horrible hacks we used to have
> in our I/O-APIC/timer code, including a command-line override
> parameter, needed so that some systems would boot at all.
>
> This single instance of a piece of some HP gear being twisted beyond
> belief is IMO a minor annoyance and price to pay compared to the gain.
> Please note that apart from the DSDT being buggy on this machine, it
> has an incorrect IRQ 0 override in the ACPI table pointing to the pin
> #2 of the I/O APIC, which is in fact routed to the output of the
> master 8259A. Additionally the pin #0 of the I/O APIC which is indeed
> routed to the output of the 8254 does not receive any interrupts,
> presumably because of some misconfiguration during BIOS
> initialisation. So in fact this machine suffers from three
> configuration problems at once of which all add up to the end result
> we can observe.

okay. Perhaps we can find some better DMI filter for affected
HP+AMD+Turion laptops - how futile that might be. No chance to have some
automated non-DMI check?

Ingo


\
 
 \ /
  Last update: 2008-10-06 19:59    [from the cache]
©2003-2011 Jasper Spaans