From ca9357bd26c2f8e7b909321eedd651f52cc30d04 Mon Sep 17 00:00:00 2001 From: "K. Y. Srinivasan" Date: Wed, 5 Aug 2015 00:52:42 -0700 Subject: Drivers: hv: vmbus: Implement a clocksource based on the TSC page The current Hyper-V clock source is based on the per-partition reference counter and this counter is being accessed via s synthetic MSR - HV_X64_MSR_TIME_REF_COUNT. Hyper-V has a more efficient way of computing the per-partition reference counter value that does not involve reading a synthetic MSR. We implement a time source based on this mechanism. Tested-by: Vivek Yadav Signed-off-by: K. Y. Srinivasan Signed-off-by: Greg Kroah-Hartman --- arch/x86/include/uapi/asm/hyperv.h | 2 ++ 1 file changed, 2 insertions(+) (limited to 'arch/x86/include') diff --git a/arch/x86/include/uapi/asm/hyperv.h b/arch/x86/include/uapi/asm/hyperv.h index f36d56bd7632..f0412c50c47b 100644 --- a/arch/x86/include/uapi/asm/hyperv.h +++ b/arch/x86/include/uapi/asm/hyperv.h @@ -27,6 +27,8 @@ #define HV_X64_MSR_VP_RUNTIME_AVAILABLE (1 << 0) /* Partition Reference Counter (HV_X64_MSR_TIME_REF_COUNT) available*/ #define HV_X64_MSR_TIME_REF_COUNT_AVAILABLE (1 << 1) +/* Partition reference TSC MSR is available */ +#define HV_X64_MSR_REFERENCE_TSC_AVAILABLE (1 << 9) /* A partition's reference time stamp counter (TSC) page */ #define HV_X64_MSR_REFERENCE_TSC 0x40000021 -- cgit