[ltp] 'nolapic' & 'noacpm=on' kernel options

Christopher Sawtell linux-thinkpad@linux-thinkpad.org
Wed, 27 Jul 2005 20:35:03 +1200


On Wed, 27 Jul 2005 19:00, Pino Giaquinto wrote:
> From an old message:
> >Thinkpads have excellent APM support.  Append these
> >to the kernel command:  acpi=3Doff acpm=3Don nolapic
>
> I have just 'acpi=3Doff' option on my T30 (FC4)...
> I must add 'acpm=3Don' option?
> What does 'nolapic' option?
=46rom the Linux Kernel help page.

CONFIG_X86_UP_APIC:                                                        =
                  =20
A local APIC (Advanced Programmable Interrupt Controller) is an
integrated interrupt controller in the CPU. If you have a single-CPU system=
=20
which has a processor with a local APIC, you can say Y here to enable and u=
se=20
it. If you say Y here even though your machine doesn't have a local APIC,=20
then the kernel will still run with no slowdown at all. The local APIC=20
supports CPU-generated self-interrupts (timer performance counters), and th=
e=20
NMI watchdog which detects hard lockups.

So the 'nolapic' option disables this.

=46or the whole 9 yards, See also:
http://www.intel.com/design/chipsets/datashts/290566.htm
and links therefrom.

=2D-
CS