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diff --git a/PerformancePkg/Library/TscTimerLib/PeiTscTimerLib.c b/PerformancePkg/Library/TscTimerLib/PeiTscTimerLib.c
new file mode 100644
index 000000000..af3600b00
--- /dev/null
+++ b/PerformancePkg/Library/TscTimerLib/PeiTscTimerLib.c
@@ -0,0 +1,76 @@
+/** @file
+  A Pei Timer Library implementation which uses the Time Stamp Counter in the processor.
+
+  For Pentium 4 processors, Intel Xeon processors (family [0FH], models [03H and higher]);
+    for Intel Core Solo and Intel Core Duo processors (family [06H], model [0EH]);
+    for the Intel Xeon processor 5100 series and Intel Core 2 Duo processors (family [06H], model [0FH]);
+    for Intel Core 2 and Intel Xeon processors (family [06H], display_model [17H]);
+    for Intel Atom processors (family [06H], display_model [1CH]):
+  the time-stamp counter increments at a constant rate.
+  That rate may be set by the maximum core-clock to bus-clock ratio of the processor or may be set by
+  the maximum resolved frequency at which the processor is booted. The maximum resolved frequency may
+  differ from the maximum qualified frequency of the processor.
+
+  The specific processor configuration determines the behavior. Constant TSC behavior ensures that the
+  duration of each clock tick is uniform and supports the use of the TSC as a wall clock timer even if
+  the processor core changes frequency. This is the architectural behavior moving forward.
+
+  A Processor's support for invariant TSC is indicated by CPUID.0x80000007.EDX[8].
+
+  Copyright (c) 2009 - 2011, 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 <PiPei.h>
+#include <Library/HobLib.h>
+#include <Guid/TscFrequency.h>
+#include "TscTimerLibInternal.h"
+
+/**  Get TSC frequency from TSC frequency GUID HOB, if the HOB is not found, build it.
+
+  @return The number of TSC counts per second.
+
+**/
+UINT64
+InternalGetTscFrequency (
+  VOID
+  )
+{
+  EFI_HOB_GUID_TYPE       *GuidHob;
+  VOID        *DataInHob;
+  UINT64      TscFrequency;
+
+  //
+  // Get TSC frequency from TSC frequency GUID HOB.
+  //
+  GuidHob = GetFirstGuidHob (&gEfiTscFrequencyGuid);
+  if (GuidHob != NULL) {
+    DataInHob = GET_GUID_HOB_DATA (GuidHob);
+    TscFrequency = * (UINT64 *) DataInHob;
+    return TscFrequency;
+  }
+
+  //
+  // TSC frequency GUID HOB is not found, build it.
+  //
+
+  TscFrequency = InternalCalculateTscFrequency ();
+  //
+  // TscFrequency is now equal to the number of TSC counts per second, build GUID HOB for it.
+  //
+  BuildGuidDataHob (
+    &gEfiTscFrequencyGuid,
+    &TscFrequency,
+    sizeof (UINT64)
+    );
+
+  return TscFrequency;
+}
+