diff --git a/UefiCpuPkg/Include/Library/MpInitLib.h b/UefiCpuPkg/Include/Library/MpInitLib.h
index fa82529373..31eb227f12 100644
--- a/UefiCpuPkg/Include/Library/MpInitLib.h
+++ b/UefiCpuPkg/Include/Library/MpInitLib.h
@@ -1,7 +1,7 @@
 /** @file
   Multiple-Processor initialization Library.
 
-  Copyright (c) 2016, Intel Corporation. All rights reserved.<BR>
+  Copyright (c) 2016 - 2019, Intel Corporation. All rights reserved.<BR>
   SPDX-License-Identifier: BSD-2-Clause-Patent
 
 **/
@@ -344,4 +344,38 @@ MpInitLibWhoAmI (
   OUT UINTN                    *ProcessorNumber
   );
 
+/**
+  This service executes a caller provided function on all enabled CPUs.
+
+  @param[in]  Procedure               A pointer to the function to be run on
+                                      enabled APs of the system. See type
+                                      EFI_AP_PROCEDURE.
+  @param[in]  TimeoutInMicroseconds   Indicates the time limit in microseconds for
+                                      APs to return from Procedure, either for
+                                      blocking or non-blocking mode. Zero means
+                                      infinity. TimeoutInMicroseconds is ignored
+                                      for BSP.
+  @param[in]  ProcedureArgument       The parameter passed into Procedure for
+                                      all APs.
+
+  @retval EFI_SUCCESS             In blocking mode, all CPUs have finished before
+                                  the timeout expired.
+  @retval EFI_SUCCESS             In non-blocking mode, function has been dispatched
+                                  to all enabled CPUs.
+  @retval EFI_DEVICE_ERROR        Caller processor is AP.
+  @retval EFI_NOT_READY           Any enabled APs are busy.
+  @retval EFI_NOT_READY           MP Initialize Library is not initialized.
+  @retval EFI_TIMEOUT             In blocking mode, the timeout expired before
+                                  all enabled APs have finished.
+  @retval EFI_INVALID_PARAMETER   Procedure is NULL.
+
+**/
+EFI_STATUS
+EFIAPI
+MpInitLibStartupAllCPUs (
+  IN  EFI_AP_PROCEDURE          Procedure,
+  IN  UINTN                     TimeoutInMicroseconds,
+  IN  VOID                      *ProcedureArgument      OPTIONAL
+  );
+
 #endif