2006-11-14 21:58:53

by J.A. Magallón

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Subject: SMP and ACPI

Hi...

Stupid question of the day: is it still needed to select ACPI manually to
get SMP working, or does SMP select the minimal part of ACPI that is needed ?

TIA

--
J.A. Magallon <jamagallon()ono!com> \ Software is like sex:
\ It's better when it's free
Mandriva Linux release 2007.1 (Cooker) for i586
Linux 2.6.18-jam12 (gcc 4.1.1 20060724 (prerelease) (4.1.1-3mdk)) #1 SMP PREEMPT


2006-11-15 07:13:46

by Brown, Len

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Subject: Re: SMP and ACPI

On Tuesday 14 November 2006 16:58, J.A. Magall?n wrote:

>... is it still needed to select ACPI manually to
> get SMP working, or does SMP select the minimal part of ACPI that is needed ?

if speaking of recent 2.6...

CONFIG_SMP and CONFIG_ACPI are independent.

So if you select CONFIG_SMP and don't select CONFIG_ACPI,
then your PC will need to support MPS if Linux is going to bring up the processors...

There no longer exists a build-time concept of "minimal part of ACPI that is needed" --
you either include CONFIG_ACPI or you exclude it. However, at boot-time, "acpi=ht"
is still present -- primarily for some old systems with HT that didn't run ACPI well.
No idea if this this is still needed in practice but occasionally acpi=ht comes in handy
to debug table related issues.

-Len