IntelSiliconPkg/IntelVtd: Consume VTd policy PCD

Cc: Star Zeng <star.zeng@intel.com>
Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Jiewen Yao <jiewen.yao@intel.com>
Reviewed-by: Star Zeng <star.zeng@intel.com>
(cherry picked from commit c50596a701)

IntelSiliconPkg/IntelVTdDxe/DmaProtection.c

@@ -437,9 +437,12 @@ OnExitBootServices (
 {
   DEBUG ((DEBUG_INFO, "Vtd OnExitBootServices\n"));
   DumpVtdRegsAll ();
+
+  if ((PcdGet8(PcdVTdPolicyPropertyMask) & BIT1) == 0) {
     DisableDmar ();
     DumpVtdRegsAll ();
   }
+}
 
 /**
   Legacy boot callback function.

IntelSiliconPkg/IntelVTdDxe/IntelVTdDxe.c

@@ -352,6 +352,10 @@ IntelVTdInitialize (
   EFI_STATUS  Status;
   EFI_HANDLE  Handle;
 
+  if ((PcdGet8(PcdVTdPolicyPropertyMask) & BIT0) == 0) {
+    return EFI_UNSUPPORTED;
+  }
+
   InitializeDmaProtection ();
 
   Handle = NULL;

IntelSiliconPkg/IntelVTdDxe/IntelVTdDxe.inf

@@ -73,6 +73,9 @@
   gEfiPciEnumerationCompleteProtocolGuid      ## CONSUMES
   gEdkiiPlatformVTdPolicyProtocolGuid         ## SOMETIMES_CONSUMES
 
+[Pcd]
+  gIntelSiliconPkgTokenSpaceGuid.PcdVTdPolicyPropertyMask   ## CONSUMES
+
 [Depex]
   gEfiPciRootBridgeIoProtocolGuid AND
   gEfiAcpiSdtProtocolGuid