x86, AMD: Set ARAT feature on AMD processors
Support for Always Running APIC timer (ARAT) was introduced in commit db954b58 . This feature allows us to avoid switching timers from LAPIC to something else (e.g. HPET) and go into timer broadcasts when entering deep C-states. AMD processors don't provide a CPUID bit for that feature but they also keep APIC timers running in deep C-states (except for cases when the processor is affected by erratum 400). Therefore we should set ARAT feature bit on AMD CPUs. Tested-by: Borislav Petkov <borislav.petkov@amd.com> Acked-by: Andreas Herrmann <andreas.herrmann3@amd.com> Acked-by: Mark Langsdorf <mark.langsdorf@amd.com> Acked-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Boris Ostrovsky <boris.ostrovsky@amd.com> LKML-Reference: <1300205624-4813-1-git-send-email-ostr@amd64.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
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