[PATCH v1 1/1] MdePkg: add SmmCpuRendezvousLib.h and SmmCpuRendezvousLibNull implement.

["Li, Zhihao" <zhihao.li@intel.com>]

REF： https://bugzilla.tianocore.org/show_bug.cgi?id=3912

UefiCpuPkg define a new Protocol with the new services
SmmWaitForAllProcessor(), which can be used by SMI handler
to optionally wait for other APs to complete SMM rendezvous in
relaxed AP mode.

VariableSmm and VariableStandaloneMM driver in MdeModulePkg need
to use this services but MdeModulePkg can't depend on UefiCpuPkg.

Thus, the solution is moving SmmCpuRendezvouslib.h from UefiCpuPkg
to MdePkg and creating SmmCpuRendezvousLib NullLib version
implementation in MdePkg as dependency for the pkg that can't
depend on UefiCpuPkg.

Cc: Michael D Kinney <michael.d.kinney@intel.com>
Cc: Liming Gao <gaoliming@byosoft.com.cn>
Cc: Eric Dong <eric.dong@intel.com>
Cc: Ray Ni <ray.ni@intel.com>
Cc: Michael Kubacki <mikuback@linux.microsoft.com>
Cc: Siyuan Fu <siyuan.fu@intel.com>

Signed-off-by: Zhihao Li <zhihao.li@intel.com>
---
 MdePkg/Library/SmmCpuRendezvousLibNull/SmmCpuRendezvousLibNull.c   | 29 ++++++++++++++++++++
 {UefiCpuPkg => MdePkg}/Include/Library/SmmCpuRendezvousLib.h       |  0
 MdePkg/Library/SmmCpuRendezvousLibNull/SmmCpuRendezvousLibNull.inf | 26 ++++++++++++++++++
 MdePkg/MdePkg.dec                                                  |  3 ++
 MdePkg/MdePkg.dsc                                                  |  1 +
 UefiCpuPkg/UefiCpuPkg.dec                                          |  3 --
 6 files changed, 59 insertions(+), 3 deletions(-)

diff --git a/MdePkg/Library/SmmCpuRendezvousLibNull/SmmCpuRendezvousLibNull.c b/MdePkg/Library/SmmCpuRendezvousLibNull/SmmCpuRendezvousLibNull.c
new file mode 100644
index 000000000000..474195bbb374
--- /dev/null
+++ b/MdePkg/Library/SmmCpuRendezvousLibNull/SmmCpuRendezvousLibNull.c
@@ -0,0 +1,29 @@
+/** @file
+  SMM CPU Rendezvous sevice implement.
+
+  Copyright (c) 2022, Intel Corporation. All rights reserved.<BR>
+  SPDX-License-Identifier: BSD-2-Clause-Patent
+
+**/
+
+#include <Library/DebugLib.h>
+#include <Library/SmmCpuRendezvousLib.h>
+
+/**
+  This routine wait for all AP processors to arrive in SMM.
+
+  @param[in] BlockingMode  Blocking mode or non-blocking mode.
+
+  @retval EFI_SUCCESS  All avaiable APs arrived.
+  @retval EFI_TIMEOUT  Wait for all APs until timeout.
+  @retval OTHER        Fail to register SMM CPU Rendezvous service Protocol.
+**/
+EFI_STATUS
+EFIAPI
+SmmWaitForAllProcessor (
+  IN BOOLEAN  BlockingMode
+  )
+{
+  ASSERT (FALSE);
+  return EFI_SUCCESS;
+}
diff --git a/UefiCpuPkg/Include/Library/SmmCpuRendezvousLib.h b/MdePkg/Include/Library/SmmCpuRendezvousLib.h
similarity index 100%
rename from UefiCpuPkg/Include/Library/SmmCpuRendezvousLib.h
rename to MdePkg/Include/Library/SmmCpuRendezvousLib.h
diff --git a/MdePkg/Library/SmmCpuRendezvousLibNull/SmmCpuRendezvousLibNull.inf b/MdePkg/Library/SmmCpuRendezvousLibNull/SmmCpuRendezvousLibNull.inf
new file mode 100644
index 000000000000..7c9bac9af2ff
--- /dev/null
+++ b/MdePkg/Library/SmmCpuRendezvousLibNull/SmmCpuRendezvousLibNull.inf
@@ -0,0 +1,26 @@
+## @file
+# SMM CPU Rendezvous service lib.
+#
+# This is SMM CPU rendezvous service lib that wait for all
+# APs to enter SMM mode.
+#
+# Copyright (c) 2022, Intel Corporation. All rights reserved.<BR>
+# SPDX-License-Identifier: BSD-2-Clause-Patent
+#
+##
+
+[Defines]
+  INF_VERSION                    = 0x00010005
+  BASE_NAME                      = SmmCpuRendezvousLibNull
+  FILE_GUID                      = 1e5790ea-d013-4d7b-9047-b4342a762027
+  MODULE_TYPE                    = DXE_SMM_DRIVER
+  LIBRARY_CLASS                  = SmmCpuRendezvousLib|MM_STANDALONE DXE_SMM_DRIVER
+
+[Sources]
+  SmmCpuRendezvousLibNull.c
+
+[Packages]
+  MdePkg/MdePkg.dec
+
+[LibraryClasses]
+  DebugLib
diff --git a/MdePkg/MdePkg.dec b/MdePkg/MdePkg.dec
index faeb28c80cbd..85a4398e8f65 100644
--- a/MdePkg/MdePkg.dec
+++ b/MdePkg/MdePkg.dec
@@ -272,6 +272,9 @@
   #
   CcProbeLib|Include/Library/CcProbeLib.h
 
+  ## @libraryclass  Provides function for SMM CPU Rendezvous Library.
+  SmmCpuRendezvousLib|Include/Library/SmmCpuRendezvousLib.h
+
 [LibraryClasses.IA32, LibraryClasses.X64, LibraryClasses.AARCH64]
   ##  @libraryclass  Provides services to generate random number.
   #
diff --git a/MdePkg/MdePkg.dsc b/MdePkg/MdePkg.dsc
index c8d282882ec1..5e2ea32088fa 100644
--- a/MdePkg/MdePkg.dsc
+++ b/MdePkg/MdePkg.dsc
@@ -131,6 +131,7 @@
 
   MdePkg/Library/RegisterFilterLibNull/RegisterFilterLibNull.inf
   MdePkg/Library/CcProbeLibNull/CcProbeLibNull.inf
+  MdePkg/Library/SmmCpuRendezvousLibNull/SmmCpuRendezvousLibNull.inf
 
 [Components.IA32, Components.X64, Components.ARM, Components.AARCH64]
   #
diff --git a/UefiCpuPkg/UefiCpuPkg.dec b/UefiCpuPkg/UefiCpuPkg.dec
index 525cde463435..1951eb294c6c 100644
--- a/UefiCpuPkg/UefiCpuPkg.dec
+++ b/UefiCpuPkg/UefiCpuPkg.dec
@@ -62,9 +62,6 @@
   ##  @libraryclass  Provides function for loading microcode.
   MicrocodeLib|Include/Library/MicrocodeLib.h
 
-  ## @libraryclass  Provides function for SMM CPU Rendezvous Library.
-  SmmCpuRendezvousLib|Include/Library/SmmCpuRendezvousLib.h
-
 [Guids]
   gUefiCpuPkgTokenSpaceGuid      = { 0xac05bf33, 0x995a, 0x4ed4, { 0xaa, 0xb8, 0xef, 0x7a, 0xe8, 0xf, 0x5c, 0xb0 }}
   gMsegSmramGuid                 = { 0x5802bce4, 0xeeee, 0x4e33, { 0xa1, 0x30, 0xeb, 0xad, 0x27, 0xf0, 0xe4, 0x39 }}
-- 
2.26.2.windows.1