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| author | Shaohua Li <shaohua.li@intel.com> | 2009-08-12 11:16:12 +0800 |
|---|---|---|
| committer | Ingo Molnar <mingo@elte.hu> | 2009-08-12 16:45:02 +0200 |
| commit | 39fe05e58c5e448601ce46e6b03900d5bf31c4b0 (patch) | |
| tree | e01978c90faa2e534d7c9af67647aa61f2242bcd | |
| parent | 7cb7beb31aa3d941833b6a6e553687422c31e4b6 (diff) | |
| download | linux-39fe05e58c5e448601ce46e6b03900d5bf31c4b0.tar.bz2 | |
x86, hpet: Disable per-cpu hpet timer if ARAT is supported
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>
| -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 dedc2bddf7a5..5969e1078fc2 100644 --- a/arch/x86/kernel/hpet.c +++ b/arch/x86/kernel/hpet.c @@ -584,6 +584,8 @@ static void hpet_msi_capability_lookup(unsigned int start_timer) unsigned int num_timers_used = 0; int i; + if (boot_cpu_has(X86_FEATURE_ARAT)) + return; id = hpet_readl(HPET_ID); num_timers = ((id & HPET_ID_NUMBER) >> HPET_ID_NUMBER_SHIFT); @@ -872,10 +874,8 @@ 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: @@ -908,9 +908,17 @@ 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 (boot_cpu_has(X86_FEATURE_ARAT)) + return 0; + for_each_online_cpu(cpu) { hpet_cpuhp_notify(NULL, CPU_ONLINE, (void *)(long)cpu); } |