diff options
| author | Shaohua Li <shaohua.li@intel.com> | 2009-08-12 11:16:12 +0800 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@suse.de> | 2011-03-02 09:46:35 -0500 |
| commit | bf8c4fb74755a0b72e013c2bdcdb6a97b544081e (patch) | |
| tree | 1f12792907ee09a93d0496c64a8a24237fc7374b /arch | |
| parent | cfa3f57bab83b586b948fd40d3558243d55818b2 (diff) | |
x86, hpet: Disable per-cpu hpet timer if ARAT is supported
commit 39fe05e58c5e448601ce46e6b03900d5bf31c4b0 upstream.
If CPU support always running local APIC timer, per-cpu hpet
timer could be disabled, which is useless and wasteful in such
case. Let's leave the timers to others.
The effect is that we reserve less timers.
Signed-off-by: Shaohua Li <shaohua.li@intel.com>
Cc: venkatesh.pallipadi@intel.com
LKML-Reference: <20090812031612.GA10062@sli10-desk.sh.intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Renninger <trenn@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Diffstat (limited to 'arch')
| -rw-r--r-- | arch/x86/kernel/hpet.c | 12 |
1 files changed, 10 insertions, 2 deletions
diff --git a/arch/x86/kernel/hpet.c b/arch/x86/kernel/hpet.c index c771e1a37b9..69cab241341 100644 --- a/arch/x86/kernel/hpet.c +++ b/arch/x86/kernel/hpet.c @@ -606,6 +606,8 @@ static void hpet_msi_capability_lookup(unsigned int start_timer) if (hpet_msi_disable) return; + if (boot_cpu_has(X86_FEATURE_ARAT)) + return; id = hpet_readl(HPET_ID); num_timers = ((id & HPET_ID_NUMBER) >> HPET_ID_NUMBER_SHIFT); @@ -894,10 +896,8 @@ int __init hpet_enable(void) if (id & HPET_ID_LEGSUP) { hpet_legacy_clockevent_register(); - hpet_msi_capability_lookup(2); return 1; } - hpet_msi_capability_lookup(0); return 0; out_nohpet: @@ -930,12 +930,20 @@ static __init int hpet_late_init(void) if (!hpet_virt_address) return -ENODEV; + if (hpet_readl(HPET_ID) & HPET_ID_LEGSUP) + hpet_msi_capability_lookup(2); + else + hpet_msi_capability_lookup(0); + hpet_reserve_platform_timers(hpet_readl(HPET_ID)); hpet_print_config(); if (hpet_msi_disable) return 0; + if (boot_cpu_has(X86_FEATURE_ARAT)) + return 0; + for_each_online_cpu(cpu) { hpet_cpuhp_notify(NULL, CPU_ONLINE, (void *)(long)cpu); } |