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diff --git a/Core/MdePkg/Library/UefiPalLib/UefiPalLib.c b/Core/MdePkg/Library/UefiPalLib/UefiPalLib.c
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+++ b/Core/MdePkg/Library/UefiPalLib/UefiPalLib.c
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+/** @file
+  PAL Library implementation retrieving the PAL Entry Point from the SAL System Table
+  register in the EFI System Confguration Table.
+
+  Copyright (c) 2007 - 2008, 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 <PiDxe.h>
+
+#include <IndustryStandard/Sal.h>
+#include <Library/UefiLib.h>
+#include <Library/BaseLib.h>
+#include <Library/DebugLib.h>
+
+#include <Guid/SalSystemTable.h>
+
+UINT64               mPalProcEntry;
+
+/**
+  Makes a PAL procedure call.
+
+  This is a wrapper function to make a PAL procedure call.  Based on the Index value,
+  this API will make static or stacked PAL call. Architected procedures may be designated
+  as required or optional.  If a PAL procedure is specified as optional, a unique return
+  code of 0xFFFFFFFFFFFFFFFF is returned in the Status field of the PAL_CALL_RETURN structure.
+  This indicates that the procedure is not present in this PAL implementation.  It is the
+  caller's responsibility to check for this return code after calling any optional PAL
+  procedure. No parameter checking is performed on the 4 input parameters, but there are
+  some common rules that the caller should follow when making a PAL call.  Any address
+  passed to PAL as buffers for return parameters must be 8-byte aligned.  Unaligned addresses
+  may cause undefined results.  For those parameters defined as reserved or some fields
+  defined as reserved must be zero filled or the invalid argument return value may be
+  returned or undefined result may occur during the execution of the procedure.
+  This function is only available on IPF.
+
+  @param Index  The PAL procedure Index number.
+  @param Arg2   The 2nd parameter for PAL procedure calls.
+  @param Arg3   The 3rd parameter for PAL procedure calls.
+  @param Arg4   The 4th parameter for PAL procedure calls.
+
+  @return Structure returned from the PAL Call procedure, including the status and return value.
+
+**/
+PAL_CALL_RETURN
+EFIAPI
+PalCall (
+  IN UINT64                  Index,
+  IN UINT64                  Arg2,
+  IN UINT64                  Arg3,
+  IN UINT64                  Arg4
+  )
+{
+  //
+  // mPalProcEntry is initialized in library constructor as PAL entry.
+  //
+  return AsmPalCall (
+           mPalProcEntry,
+           Index,
+           Arg2,
+           Arg3,
+           Arg4
+           );
+
+}
+
+/**
+  The constructor function of UEFI Pal Lib.
+
+  The constructor function looks up the SAL System Table in the EFI System Configuration
+  Table. Once the SAL System Table is found, the PAL Entry Point in the SAL System Table
+  will be derived and stored into a global variable for library usage.
+  It will ASSERT() if the SAL System Table cannot be found or the data in the SAL System
+  Table is not the valid data.
+
+  @param  ImageHandle   The firmware allocated handle for the EFI image.
+  @param  SystemTable   A pointer to the EFI System Table.
+
+  @retval EFI_SUCCESS   The constructor always returns EFI_SUCCESS.
+
+**/
+EFI_STATUS
+EFIAPI
+UefiPalLibConstructor (
+  IN EFI_HANDLE        ImageHandle,
+  IN EFI_SYSTEM_TABLE  *SystemTable
+  )
+{
+  EFI_STATUS                     Status;
+  SAL_ST_ENTRY_POINT_DESCRIPTOR  *SalStEntryDes;
+  SAL_SYSTEM_TABLE_HEADER        *SalSystemTable;
+
+  Status = EfiGetSystemConfigurationTable (
+             &gEfiSalSystemTableGuid,
+             (VOID **) &SalSystemTable
+             );
+  ASSERT_EFI_ERROR (Status);
+  ASSERT (SalSystemTable != NULL);
+
+  //
+  // Check the first entry of SAL System Table,
+  // because the SAL entry is in ascending order with the entry type,
+  // the type 0 entry should be the first if exist.
+  //
+  SalStEntryDes = (SAL_ST_ENTRY_POINT_DESCRIPTOR *)(SalSystemTable + 1);
+
+  //
+  // Assure the SAL ENTRY Type is 0
+  //
+  ASSERT (SalStEntryDes->Type == EFI_SAL_ST_ENTRY_POINT);
+
+  mPalProcEntry = SalStEntryDes->PalProcEntry;
+  //
+  // Make sure the PalCallAddress has the valid value
+  //
+  ASSERT (mPalProcEntry != 0);
+
+  return EFI_SUCCESS;
+}