diff options
Diffstat (limited to 'PcAtChipsetPkg/Library/AcpiTimerLib/BaseAcpiTimerLib.c')
-rw-r--r-- | PcAtChipsetPkg/Library/AcpiTimerLib/BaseAcpiTimerLib.c | 42 |
1 files changed, 42 insertions, 0 deletions
diff --git a/PcAtChipsetPkg/Library/AcpiTimerLib/BaseAcpiTimerLib.c b/PcAtChipsetPkg/Library/AcpiTimerLib/BaseAcpiTimerLib.c new file mode 100644 index 0000000000..21fdb79908 --- /dev/null +++ b/PcAtChipsetPkg/Library/AcpiTimerLib/BaseAcpiTimerLib.c @@ -0,0 +1,42 @@ +/** @file
+ ACPI Timer implements one instance of Timer Library.
+
+ Copyright (c) 2013 - 2014, Intel Corporation. All rights reserved.<BR>
+ This program and the accompanying materials
+ are licensed and made available under the terms and conditions of the BSD License
+ which accompanies this distribution. The full text of the license may be found at
+ http://opensource.org/licenses/bsd-license.php
+
+ THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
+ WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
+
+**/
+
+#include <Base.h>
+#include <Library/TimerLib.h>
+#include <Library/BaseLib.h>
+
+/**
+ 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
+ )
+{
+ BOOLEAN InterruptState;
+ UINT64 Count;
+ UINT64 Frequency;
+
+ InterruptState = SaveAndDisableInterrupts ();
+ Count = GetPerformanceCounter ();
+ MicroSecondDelay (100);
+ Frequency = MultU64x32 (GetPerformanceCounter () - Count, 10000);
+ SetInterruptState (InterruptState);
+ return Frequency;
+}
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