MdePkg: Add CcProbeLibNull

BZ: https://bugzilla.tianocore.org/show_bug.cgi?id=3902

CcProbeLib is used to probe the Confidential Computing guest type.
This library is designed to run on SEC / PEI / DXE phases. A null
instance of the library always returns CCGuestTypeNonEncrypted.
A platform specific CcProbeLib will be implemented, for example,
in OvmfPkg.

Cc: Michael D Kinney <michael.d.kinney@intel.com>
Cc: Liming Gao <gaoliming@byosoft.com.cn>
Cc: Zhiguang Liu <zhiguang.liu@intel.com>
Cc: James Bottomley <jejb@linux.ibm.com>
Cc: Jiewen Yao <jiewen.yao@intel.com>
Cc: Gerd Hoffmann <kraxel@redhat.com>
Reviewed-by: Liming Gao <gaoliming@byosoft.com.cn>
Reviewed-by: Jiewen Yao <jiewen.yao@intel.com>
Reviewed-by: Tom Lendacky <thomas.lendacky@amd.com>
Signed-off-by: Min Xu <min.m.xu@intel.com>

MdePkg/Include/Library/CcProbeLib.h

@@ -0,0 +1,26 @@
+/** @file
+
+Copyright (c) 2022, Intel Corporation. All rights reserved.<BR>
+SPDX-License-Identifier: BSD-2-Clause-Patent
+
+**/
+
+#ifndef CC_PROBE_LIB_H_
+#define CC_PROBE_LIB_H_
+
+#include <ConfidentialComputingGuestAttr.h>
+
+/**
+  Probe the ConfidentialComputing Guest type. See defition of
+  CC_GUEST_TYPE in <ConfidentialComputingGuestAttr.h>.
+
+  @return The guest type
+
+**/
+UINT8
+EFIAPI
+CcProbe (
+  VOID
+  );
+
+#endif

MdePkg/Library/CcProbeLibNull/CcProbeLibNull.c

@@ -0,0 +1,26 @@
+/** @file
+
+  Null stub of CcProbeLib
+
+  Copyright (c) 2022, Intel Corporation. All rights reserved.<BR>
+  SPDX-License-Identifier: BSD-2-Clause-Patent
+
+**/
+
+#include <Library/CcProbeLib.h>
+
+/**
+  Probe the ConfidentialComputing Guest type. See defition of
+  CC_GUEST_TYPE in <ConfidentialComputingGuestAttr.h>.
+
+  @return The guest type
+
+**/
+UINT8
+EFIAPI
+CcProbe (
+  VOID
+  )
+{
+  return CcGuestTypeNonEncrypted;
+}

MdePkg/Library/CcProbeLibNull/CcProbeLibNull.inf

@@ -0,0 +1,21 @@
+## @file
+# CcProbeLib null instance.
+#
+#  Copyright (c) 2022, Intel Corporation. All rights reserved.<BR>
+#  SPDX-License-Identifier: BSD-2-Clause-Patent
+#
+##
+
+[Defines]
+  INF_VERSION                    = 0x00010005
+  BASE_NAME                      = CcProbeLibNull
+  FILE_GUID                      = B15D67FE-0DAC-4316-8E26-8A6b85E43782
+  MODULE_TYPE                    = BASE
+  VERSION_STRING                 = 1.0
+  LIBRARY_CLASS                  = CcProbeLib
+
+[Sources]
+  CcProbeLibNull.c
+
+[Packages]
+  MdePkg/MdePkg.dec

MdePkg/MdePkg.dec

@@ -267,6 +267,11 @@
   #
   RegisterFilterLib|Include/Library/RegisterFilterLib.h
 
+  ##  @libraryclass  This library provides interfances to probe ConfidentialComputing guest type.
+  #
+  #
+  CcProbeLib|Include/Library/CcProbeLib.h
+
 [LibraryClasses.IA32, LibraryClasses.X64, LibraryClasses.AARCH64]
   ##  @libraryclass  Provides services to generate random number.
   #

MdePkg/MdePkg.dsc

@@ -130,6 +130,7 @@
   MdePkg/Library/StandaloneMmServicesTableLib/StandaloneMmServicesTableLib.inf
 
   MdePkg/Library/RegisterFilterLibNull/RegisterFilterLibNull.inf
+  MdePkg/Library/CcProbeLibNull/CcProbeLibNull.inf
 
 [Components.IA32, Components.X64, Components.ARM, Components.AARCH64]
   #