3 files changed, 38 insertions, 2 deletions
diff --git a/OvmfPkg/Tcg/Tcg2Config/Tcg2ConfigPei.inf b/OvmfPkg/Tcg/Tcg2Config/Tcg2ConfigPei.inf
index aa996b7da7..194ebfba64 100644
--- a/OvmfPkg/Tcg/Tcg2Config/Tcg2ConfigPei.inf
+++ b/OvmfPkg/Tcg/Tcg2Config/Tcg2ConfigPei.inf
@@ -21,9 +21,14 @@
 
 [Sources]
   Tcg2ConfigPeim.c
-  Tpm12Support.c
   Tpm12Support.h
 
+[Sources.IA32, Sources.X64]
+  Tpm12Support.c
+
+[Sources.ARM, Sources.AARCH64]
+  Tpm12SupportNull.c
+
 [Packages]
   MdePkg/MdePkg.dec
   MdeModulePkg/MdeModulePkg.dec
@@ -35,9 +40,11 @@
   BaseLib
   DebugLib
   PeiServicesLib
-  Tpm12DeviceLib
   Tpm2DeviceLib
 
+[LibraryClasses.IA32, LibraryClasses.X64]
+  Tpm12DeviceLib
+
 [Guids]
   gEfiTpmDeviceSelectedGuid           ## PRODUCES ## GUID # Used as a PPI GUID
   gEfiTpmDeviceInstanceTpm20DtpmGuid  ## SOMETIMES_CONSUMES
diff --git a/OvmfPkg/Tcg/Tcg2Config/Tpm12Support.h b/OvmfPkg/Tcg/Tcg2Config/Tpm12Support.h
index c739775d23..d92c432530 100644
--- a/OvmfPkg/Tcg/Tcg2Config/Tpm12Support.h
+++ b/OvmfPkg/Tcg/Tcg2Config/Tpm12Support.h
@@ -15,6 +15,10 @@
 /**
   Detect the presence of a TPM with interface version 1.2.
 
+  @retval EFI_UNSUPPORTED  The platform that includes this particular
+                           implementation of the function does not support
+                           TPM-1.2.
+
   @retval EFI_SUCCESS      TPM-1.2 available. The Tpm12RequestUseTpm() and
                            Tpm12SubmitCommand(TPM_ORD_GetTicks) operations
                            (from the Tpm12DeviceLib class) have succeeded.
diff --git a/OvmfPkg/Tcg/Tcg2Config/Tpm12SupportNull.c b/OvmfPkg/Tcg/Tcg2Config/Tpm12SupportNull.c
new file mode 100644
index 0000000000..7bb377b9b9
--- /dev/null
+++ b/OvmfPkg/Tcg/Tcg2Config/Tpm12SupportNull.c
@@ -0,0 +1,25 @@
+/** @file
+  Null implementation of InternalTpm12Detect(), always returning
+  EFI_UNSUPPORTED.
+
+  Copyright (C) 2020, Red Hat, Inc.
+
+  SPDX-License-Identifier: BSD-2-Clause-Patent
+**/
+
+#include "Tpm12Support.h"
+
+/**
+  Detect the presence of a TPM with interface version 1.2.
+
+  @retval EFI_UNSUPPORTED  The platform that includes this particular
+                           implementation of the function does not support
+                           TPM-1.2.
+**/
+EFI_STATUS
+InternalTpm12Detect (
+  VOID
+  )
+{
+  return EFI_UNSUPPORTED;
+}