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- /** @file
- CPUID Leaf 0x15 for Core Crystal Clock frequency instance as Base Timer Library.
- Copyright (c) 2019 Intel Corporation. All rights reserved.<BR>
- SPDX-License-Identifier: BSD-2-Clause-Patent
- **/
- #include <Base.h>
- #include <Library/TimerLib.h>
- #include <Library/BaseLib.h>
- /**
- CPUID Leaf 0x15 for Core Crystal Clock Frequency.
- The TSC counting frequency is determined by using CPUID leaf 0x15. Frequency in MHz = Core XTAL frequency * EBX/EAX.
- In newer flavors of the CPU, core xtal frequency is returned in ECX or 0 if not supported.
- @return The number of TSC counts per second.
- **/
- UINT64
- CpuidCoreClockCalculateTscFrequency (
- VOID
- );
- /**
- Internal function to retrieves the 64-bit frequency in Hz.
- Internal function to retrieves the 64-bit frequency in Hz.
- @return The frequency in Hz.
- **/
- UINT64
- InternalGetPerformanceCounterFrequency (
- VOID
- )
- {
- return CpuidCoreClockCalculateTscFrequency ();
- }
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