diff --git a/MdePkg/Include/Ppi/MpServices.h b/MdePkg/Include/Ppi/MpServices.h
new file mode 100644
index 0000000000..a96baf7f55
--- /dev/null
+++ b/MdePkg/Include/Ppi/MpServices.h
@@ -0,0 +1,283 @@
+/** @file
+ This file declares UEFI PI Multi-processor PPI.
+ This PPI is installed by some platform or chipset-specific PEIM that abstracts
+ handling multiprocessor support.
+
+ Copyright (c) 2015, Intel Corporation. All rights reserved.
+ 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.
+
+ @par Revision Reference:
+ This PPI is introduced in PI Version 1.4.
+
+**/
+
+#ifndef __PEI_MP_SERVICES_PPI_H__
+#define __PEI_MP_SERVICES_PPI_H__
+
+#include
+
+#define EFI_PEI_MP_SERVICES_PPI_GUID \
+ { \
+ 0xee16160a, 0xe8be, 0x47a6, { 0x82, 0xa, 0xc6, 0x90, 0xd, 0xb0, 0x25, 0xa } \
+ }
+
+typedef struct _EFI_PEI_MP_SERVICES_PPI EFI_PEI_MP_SERVICES_PPI ;
+
+/**
+ Get the number of CPU's.
+
+ @param[in] PeiServices An indirect pointer to the PEI Services Table
+ published by the PEI Foundation.
+ @param[in] This Pointer to this instance of the PPI.
+ @param[out] NumberOfProcessors Pointer to the total number of logical processors in
+ the system, including the BSP and disabled APs.
+ @param[out] NumberOfEnabledProcessors
+ Number of processors in the system that are enabled.
+
+ @retval EFI_SUCCESS The number of logical processors and enabled
+ logical processors was retrieved.
+ @retval EFI_DEVICE_ERROR The calling processor is an AP.
+ @retval EFI_INVALID_PARAMETER NumberOfProcessors is NULL.
+ NumberOfEnabledProcessors is NULL.
+**/
+typedef
+EFI_STATUS
+(EFIAPI *EFI_PEI_MP_SERVICES_GET_NUMBER_OF_PROCESSORS) (
+ IN CONST EFI_PEI_SERVICES **PeiServices,
+ IN EFI_PEI_MP_SERVICES_PPI *This,
+ OUT UINTN *NumberOfProcessors,
+ OUT UINTN *NumberOfEnabledProcessors
+ );
+
+/**
+ Get information on a specific CPU.
+
+ @param[in] PeiServices An indirect pointer to the PEI Services Table
+ published by the PEI Foundation.
+ @param[in] This Pointer to this instance of the PPI.
+ @param[in] ProcessorNumber Pointer to the total number of logical processors in
+ the system, including the BSP and disabled APs.
+ @param[out] ProcessorInfoBuffer Number of processors in the system that are enabled.
+
+ @retval EFI_SUCCESS Processor information was returned.
+ @retval EFI_DEVICE_ERROR The calling processor is an AP.
+ @retval EFI_INVALID_PARAMETER ProcessorInfoBuffer is NULL.
+ @retval EFI_NOT_FOUND The processor with the handle specified by
+ ProcessorNumber does not exist in the platform.
+**/
+typedef
+EFI_STATUS
+(EFIAPI *EFI_PEI_MP_SERVICES_GET_PROCESSOR_INFO) (
+ IN CONST EFI_PEI_SERVICES **PeiServices,
+ IN EFI_PEI_MP_SERVICES_PPI *This,
+ IN UINTN ProcessorNumber,
+ OUT EFI_PROCESSOR_INFORMATION *ProcessorInfoBuffer
+ );
+
+/**
+ Activate all of the application proessors.
+
+ @param[in] PeiServices An indirect pointer to the PEI Services Table
+ published by the PEI Foundation.
+ @param[in] This A pointer to the EFI_PEI_MP_SERVICES_PPI instance.
+ @param[in] Procedure A pointer to the function to be run on enabled APs of
+ the system.
+ @param[in] SingleThread If TRUE, then all the enabled APs execute the function
+ specified by Procedure one by one, in ascending order
+ of processor handle number. If FALSE, then all the
+ enabled APs execute the function specified by Procedure
+ simultaneously.
+ @param[in] TimeoutInMicroSeconds
+ Indicates the time limit in microseconds for APs to
+ return from Procedure, for blocking mode only. Zero
+ means infinity. If the timeout expires before all APs
+ return from Procedure, then Procedure on the failed APs
+ is terminated. All enabled APs are available for next
+ function assigned by EFI_PEI_MP_SERVICES_PPI.StartupAllAPs()
+ or EFI_PEI_MP_SERVICES_PPI.StartupThisAP(). If the
+ timeout expires in blocking mode, BSP returns
+ EFI_TIMEOUT.
+ @param[in] ProcedureArgument The parameter passed into Procedure for all APs.
+
+ @retval EFI_SUCCESS In blocking mode, all APs have finished before the
+ timeout expired.
+ @retval EFI_DEVICE_ERROR Caller processor is AP.
+ @retval EFI_NOT_STARTED No enabled APs exist in the system.
+ @retval EFI_NOT_READY Any enabled APs are busy.
+ @retval EFI_TIMEOUT In blocking mode, the timeout expired before all
+ enabled APs have finished.
+ @retval EFI_INVALID_PARAMETER Procedure is NULL.
+**/
+typedef
+EFI_STATUS
+(EFIAPI *EFI_PEI_MP_SERVICES_STARTUP_ALL_APS) (
+ IN CONST EFI_PEI_SERVICES **PeiServices,
+ IN EFI_PEI_MP_SERVICES_PPI *This,
+ IN EFI_AP_PROCEDURE Procedure,
+ IN BOOLEAN SingleThread,
+ IN UINTN TimeoutInMicroSeconds,
+ IN VOID *ProcedureArgument OPTIONAL
+ );
+
+/**
+ Activate a specific application processor.
+
+ @param[in] PeiServices An indirect pointer to the PEI Services Table
+ published by the PEI Foundation.
+ @param[in] This A pointer to the EFI_PEI_MP_SERVICES_PPI instance.
+ @param[in] Procedure A pointer to the function to be run on enabled APs of
+ the system.
+ @param[in] ProcessorNumber The handle number of the AP. The range is from 0 to the
+ total number of logical processors minus 1. The total
+ number of logical processors can be retrieved by
+ EFI_PEI_MP_SERVICES_PPI.GetNumberOfProcessors().
+ @param[in] TimeoutInMicroSeconds
+ Indicates the time limit in microseconds for APs to
+ return from Procedure, for blocking mode only. Zero
+ means infinity. If the timeout expires before all APs
+ return from Procedure, then Procedure on the failed APs
+ is terminated. All enabled APs are available for next
+ function assigned by EFI_PEI_MP_SERVICES_PPI.StartupAllAPs()
+ or EFI_PEI_MP_SERVICES_PPI.StartupThisAP(). If the
+ timeout expires in blocking mode, BSP returns
+ EFI_TIMEOUT.
+ @param[in] ProcedureArgument The parameter passed into Procedure for all APs.
+
+ @retval EFI_SUCCESS In blocking mode, specified AP finished before the
+ timeout expires.
+ @retval EFI_DEVICE_ERROR The calling processor is an AP.
+ @retval EFI_TIMEOUT In blocking mode, the timeout expired before the
+ specified AP has finished.
+ @retval EFI_NOT_FOUND The processor with the handle specified by
+ ProcessorNumber does not exist.
+ @retval EFI_INVALID_PARAMETER ProcessorNumber specifies the BSP or disabled AP.
+ @retval EFI_INVALID_PARAMETER Procedure is NULL.
+**/
+typedef
+EFI_STATUS
+(EFIAPI *EFI_PEI_MP_SERVICES_STARTUP_THIS_AP) (
+ IN CONST EFI_PEI_SERVICES **PeiServices,
+ IN EFI_PEI_MP_SERVICES_PPI *This,
+ IN EFI_AP_PROCEDURE Procedure,
+ IN UINTN ProcessorNumber,
+ IN UINTN TimeoutInMicroseconds,
+ IN VOID *ProcedureArgument OPTIONAL
+ );
+
+/**
+ Switch the boot strap processor.
+
+ @param[in] PeiServices An indirect pointer to the PEI Services Table
+ published by the PEI Foundation.
+ @param[in] This A pointer to the EFI_PEI_MP_SERVICES_PPI instance.
+ @param[in] ProcessorNumber The handle number of the AP. The range is from 0 to the
+ total number of logical processors minus 1. The total
+ number of logical processors can be retrieved by
+ EFI_PEI_MP_SERVICES_PPI.GetNumberOfProcessors().
+ @param[in] EnableOldBSP If TRUE, then the old BSP will be listed as an enabled
+ AP. Otherwise, it will be disabled.
+
+ @retval EFI_SUCCESS BSP successfully switched.
+ @retval EFI_UNSUPPORTED Switching the BSP cannot be completed prior to this
+ service returning.
+ @retval EFI_UNSUPPORTED Switching the BSP is not supported.
+ @retval EFI_SUCCESS The calling processor is an AP.
+ @retval EFI_NOT_FOUND The processor with the handle specified by
+ ProcessorNumber does not exist.
+ @retval EFI_INVALID_PARAMETER ProcessorNumber specifies the current BSP or a disabled
+ AP.
+ @retval EFI_NOT_READY The specified AP is busy.
+**/
+typedef
+EFI_STATUS
+(EFIAPI *EFI_PEI_MP_SERVICES_SWITCH_BSP) (
+ IN CONST EFI_PEI_SERVICES **PeiServices,
+ IN EFI_PEI_MP_SERVICES_PPI *This,
+ IN UINTN ProcessorNumber,
+ IN BOOLEAN EnableOldBSP
+ );
+
+/**
+ Enable or disable an application processor.
+
+ @param[in] PeiServices An indirect pointer to the PEI Services Table
+ published by the PEI Foundation.
+ @param[in] This A pointer to the EFI_PEI_MP_SERVICES_PPI instance.
+ @param[in] ProcessorNumber The handle number of the AP. The range is from 0 to the
+ total number of logical processors minus 1. The total
+ number of logical processors can be retrieved by
+ EFI_PEI_MP_SERVICES_PPI.GetNumberOfProcessors().
+ @param[in] EnableAP Specifies the new state for the processor for enabled,
+ FALSE for disabled.
+ @param[in] HealthFlag If not NULL, a pointer to a value that specifies the
+ new health status of the AP. This flag corresponds to
+ StatusFlag defined in EFI_PEI_MP_SERVICES_PPI.GetProcessorInfo().
+ Only the PROCESSOR_HEALTH_STATUS_BIT is used. All other
+ bits are ignored. If it is NULL, this parameter is
+ ignored.
+
+ @retval EFI_SUCCESS The specified AP was enabled or disabled successfully.
+ @retval EFI_UNSUPPORTED Enabling or disabling an AP cannot be completed prior
+ to this service returning.
+ @retval EFI_UNSUPPORTED Enabling or disabling an AP is not supported.
+ @retval EFI_DEVICE_ERROR The calling processor is an AP.
+ @retval EFI_NOT_FOUND Processor with the handle specified by ProcessorNumber
+ does not exist.
+ @retval EFI_INVALID_PARAMETER ProcessorNumber specifies the BSP.
+**/
+typedef
+EFI_STATUS
+(EFIAPI *EFI_PEI_MP_SERVICES_ENABLEDISABLEAP) (
+ IN CONST EFI_PEI_SERVICES **PeiServices,
+ IN EFI_PEI_MP_SERVICES_PPI *This,
+ IN UINTN ProcessorNumber,
+ IN BOOLEAN EnableAP,
+ IN UINT32 *HealthFlag OPTIONAL
+ );
+
+/**
+ Enable or disable an application processor.
+
+ @param[in] PeiServices An indirect pointer to the PEI Services Table
+ published by the PEI Foundation.
+ @param[in] This A pointer to the EFI_PEI_MP_SERVICES_PPI instance.
+ @param[out] ProcessorNumber The handle number of the AP. The range is from 0 to the
+ total number of logical processors minus 1. The total
+ number of logical processors can be retrieved by
+ EFI_PEI_MP_SERVICES_PPI.GetNumberOfProcessors().
+
+ @retval EFI_SUCCESS The current processor handle number was returned in
+ ProcessorNumber.
+ @retval EFI_INVALID_PARAMETER ProcessorNumber is NULL.
+**/
+typedef
+EFI_STATUS
+(EFIAPI *EFI_PEI_MP_SERVICES_WHOAMI) (
+ IN CONST EFI_PEI_SERVICES **PeiServices,
+ IN EFI_PEI_MP_SERVICES_PPI *This,
+ OUT UINTN *ProcessorNumber
+ );
+
+///
+/// This PPI is installed by some platform or chipset-specific PEIM that abstracts
+/// handling multiprocessor support.
+///
+struct _EFI_PEI_MP_SERVICES_PPI {
+ EFI_PEI_MP_SERVICES_GET_NUMBER_OF_PROCESSORS GetNumberOfProcessors;
+ EFI_PEI_MP_SERVICES_GET_PROCESSOR_INFO GetProcessorInfo;
+ EFI_PEI_MP_SERVICES_STARTUP_ALL_APS StartupAllAPs;
+ EFI_PEI_MP_SERVICES_STARTUP_THIS_AP StartupThisAP;
+ EFI_PEI_MP_SERVICES_SWITCH_BSP SwitchBSP;
+ EFI_PEI_MP_SERVICES_ENABLEDISABLEAP EnableDisableAP;
+ EFI_PEI_MP_SERVICES_WHOAMI WhoAmI;
+};
+
+extern EFI_GUID gEfiPeiMpServicesPpiGuid;
+
+#endif
diff --git a/MdePkg/MdePkg.dec b/MdePkg/MdePkg.dec
index b0ecdfe578..c36d4f5d05 100644
--- a/MdePkg/MdePkg.dec
+++ b/MdePkg/MdePkg.dec
@@ -780,6 +780,9 @@
## Include/Ppi/Graphics.h
gEfiPeiGraphicsPpiGuid = { 0x6ecd1463, 0x4a4a, 0x461b, { 0xaf, 0x5f, 0x5a, 0x33, 0xe3, 0xb2, 0x16, 0x2b } }
+
+ ## Include/Ppi/MpServices.h
+ gEfiPeiMpServicesPpiGuid = { 0xee16160a, 0xe8be, 0x47a6, { 0x82, 0xa, 0xc6, 0x90, 0xd, 0xb0, 0x25, 0xa } }