ACPI: Only use IPI on known broken machines (AMD, Dothan/BaniasPentium M)
authorThomas Renninger <trenn@suse.de>
Tue, 27 Feb 2007 17:13:00 +0000 (12:13 -0500)
committerLen Brown <len.brown@intel.com>
Sat, 17 Mar 2007 04:50:46 +0000 (00:50 -0400)
commit25496caec111481161e7f06bbfa12a533c43cc6f
tree8e7d2876d60406b5e932c1405b5580903d2a9043
parentdb98e0b434a6265c451ffe94ec0a29b8d0aaf587
ACPI: Only use IPI on known broken machines (AMD, Dothan/BaniasPentium M)

Use IPI for blacklisted CPUs, add parameter IPI vs LAPIC

Currently, Linux disables lapic timer for all machines with C2 and higher
C-state support.

According to Intel only specific Intel models (Banias/Dothan) are broken
in respect of not waking up from C2 with lapic.

However, I am not sure about the naming of the parameter and how it
could/should get integrated into the dyntick part
(CONFIG_GENERIC_CLOCKEVENTS). There, a more fine grained check (TSC
still running?, ..) is needed? Does this make sense (always use
CLOCK_EVT_NOTIFY_BROADCAST_ON, but use OFF if forced by use_ipi=0:
clockevents_notify(use_ipi ? CLOCK_EVT_NOTIFY_BROADCAST_ON :
CLOCK_EVT_NOTIFY_BROADCAST_OFF, &pr->id);

Signed-off-by: Thomas Renninger <trenn@suse.de>
Signed-off-by: Len Brown <len.brown@intel.com>
drivers/acpi/processor_idle.c