diff --git a/MdePkg/Include/Library/DxeServicesLib.h b/MdePkg/Include/Library/DxeServicesLib.h
index 7c1c62236d96..20aee68af558 100644
--- a/MdePkg/Include/Library/DxeServicesLib.h
+++ b/MdePkg/Include/Library/DxeServicesLib.h
@@ -305,5 +305,26 @@ GetFileDevicePathFromAnyFv (
   OUT       EFI_DEVICE_PATH_PROTOCOL  **FvFileDevicePath
   );
 
-#endif
+/**
+  Allocates one or more 4KB pages of a given type from a memory region that is
+  accessible to PEI.
+
+  Allocates the number of 4KB pages of type 'MemoryType' and returns a
+  pointer to the allocated buffer.  The buffer returned is aligned on a 4KB
+  boundary.  If Pages is 0, then NULL is returned.  If there is not enough
+  memory remaining to satisfy the request, then NULL is returned.
 
+  @param[in]  MemoryType            The memory type to allocate
+  @param[in]  Pages                 The number of 4 KB pages to allocate.
+
+  @return A pointer to the allocated buffer or NULL if allocation fails.
+
+**/
+VOID *
+EFIAPI
+AllocatePeiAccessiblePages (
+  IN EFI_MEMORY_TYPE  MemoryType,
+  IN UINTN            Pages
+  );
+
+#endif
diff --git a/MdePkg/Library/DxeServicesLib/Allocate.c b/MdePkg/Library/DxeServicesLib/Allocate.c
new file mode 100644
index 000000000000..4d118f766d49
--- /dev/null
+++ b/MdePkg/Library/DxeServicesLib/Allocate.c
@@ -0,0 +1,54 @@
+/** @file
+  DxeServicesLib memory allocation routines
+
+  Copyright (c) 2018, Linaro, Ltd. 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 <Library/UefiBootServicesTableLib.h>
+#include <Library/DxeServicesLib.h>
+
+/**
+  Allocates one or more 4KB pages of a given type from a memory region that is
+  accessible to PEI.
+
+  Allocates the number of 4KB pages of type 'MemoryType' and returns a
+  pointer to the allocated buffer.  The buffer returned is aligned on a 4KB
+  boundary.  If Pages is 0, then NULL is returned.  If there is not enough
+  memory remaining to satisfy the request, then NULL is returned.
+
+  @param[in]  MemoryType            The memory type to allocate
+  @param[in]  Pages                 The number of 4 KB pages to allocate.
+
+  @return A pointer to the allocated buffer or NULL if allocation fails.
+
+**/
+VOID *
+EFIAPI
+AllocatePeiAccessiblePages (
+  IN EFI_MEMORY_TYPE  MemoryType,
+  IN UINTN            Pages
+  )
+{
+  EFI_STATUS                  Status;
+  EFI_PHYSICAL_ADDRESS        Memory;
+
+  if (Pages == 0) {
+    return NULL;
+  }
+
+  Status = gBS->AllocatePages (AllocateAnyPages, MemoryType, Pages, &Memory);
+  if (EFI_ERROR (Status)) {
+    return NULL;
+  }
+  return (VOID *)(UINTN)Memory;
+}
diff --git a/MdePkg/Library/DxeServicesLib/DxeServicesLib.inf b/MdePkg/Library/DxeServicesLib/DxeServicesLib.inf
index bd2faf2f6f2d..50ae24f8ee22 100644
--- a/MdePkg/Library/DxeServicesLib/DxeServicesLib.inf
+++ b/MdePkg/Library/DxeServicesLib/DxeServicesLib.inf
@@ -27,12 +27,18 @@ [Defines]
   LIBRARY_CLASS                  = DxeServicesLib|DXE_CORE DXE_DRIVER DXE_RUNTIME_DRIVER DXE_SAL_DRIVER DXE_SMM_DRIVER SMM_CORE UEFI_APPLICATION UEFI_DRIVER
 
 #
-#  VALID_ARCHITECTURES           = IA32 X64 IPF EBC
+#  VALID_ARCHITECTURES           = IA32 X64 IPF EBC ARM AARCH64
 #
 
 [Sources]
   DxeServicesLib.c
 
+[Sources.IA32, Sources.IPF, Sources.EBC, Sources.ARM, Sources.AARCH64]
+  Allocate.c
+
+[Sources.X64]
+  X64/Allocate.c
+
 [Packages]
   MdePkg/MdePkg.dec
 
@@ -44,6 +50,9 @@ [LibraryClasses]
   UefiLib
   UefiBootServicesTableLib
 
+[LibraryClasses.X64]
+  HobLib
+
 [Guids]
   gEfiFileInfoGuid                              ## SOMETIMES_CONSUMES ## UNDEFINED
 
diff --git a/MdePkg/Library/DxeServicesLib/X64/Allocate.c b/MdePkg/Library/DxeServicesLib/X64/Allocate.c
new file mode 100644
index 000000000000..b6d34ba20881
--- /dev/null
+++ b/MdePkg/Library/DxeServicesLib/X64/Allocate.c
@@ -0,0 +1,69 @@
+/** @file
+  DxeServicesLib memory allocation routines
+
+  Copyright (c) 2018, Linaro, Ltd. 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 <Library/HobLib.h>
+#include <Library/UefiBootServicesTableLib.h>
+#include <Library/DxeServicesLib.h>
+
+/**
+  Allocates one or more 4KB pages of a given type from a memory region that is
+  accessible to PEI.
+
+  Allocates the number of 4KB pages of type 'MemoryType' and returns a
+  pointer to the allocated buffer.  The buffer returned is aligned on a 4KB
+  boundary.  If Pages is 0, then NULL is returned.  If there is not enough
+  memory remaining to satisfy the request, then NULL is returned.
+
+  @param[in]  MemoryType            The memory type to allocate
+  @param[in]  Pages                 The number of 4 KB pages to allocate.
+
+  @return A pointer to the allocated buffer or NULL if allocation fails.
+
+**/
+VOID *
+EFIAPI
+AllocatePeiAccessiblePages (
+  IN EFI_MEMORY_TYPE  MemoryType,
+  IN UINTN            Pages
+  )
+{
+  EFI_STATUS                  Status;
+  EFI_ALLOCATE_TYPE           AllocType;
+  EFI_PHYSICAL_ADDRESS        Memory;
+  EFI_HOB_HANDOFF_INFO_TABLE  *PhitHob;
+
+  if (Pages == 0) {
+    return NULL;
+  }
+
+  AllocType = AllocateAnyPages;
+  //
+  // A X64 build of DXE may be combined with a 32-bit build of PEI, and so we
+  // need to check the memory limit set by PEI, and allocate below 4 GB if the
+  // limit is set to 4 GB or lower.
+  //
+  PhitHob = (EFI_HOB_HANDOFF_INFO_TABLE *)GetHobList ();
+  if (PhitHob->EfiFreeMemoryTop <= MAX_UINT32) {
+    AllocType = AllocateMaxAddress;
+    Memory = MAX_UINT32;
+  }
+
+  Status = gBS->AllocatePages (AllocType, MemoryType, Pages, &Memory);
+  if (EFI_ERROR (Status)) {
+    return NULL;
+  }
+  return (VOID *)(UINTN)Memory;
+}
