OvmfPkg/PlatformPei: Add Xen support

* Make PlatformPei aware of Xen
* Fix assigned PIO and MMIO ranges to be compatible with Xen
* Reserve Xen HVM address range
* Publish XenInfo HOB
* Don't program PIIX4 PMBA for Xen

Signed-off-by: Andrei Warkentin <andreiw@motorola.com>
Reviewed-by: gavinguan
Signed-off-by: jljusten

git-svn-id: https://edk2.svn.sourceforge.net/svnroot/edk2/trunk/edk2@12091 6f19259b-4bc3-4df7-8a09-765794883524

OvmfPkg/PlatformPei/Platform.h

@@ -1,7 +1,7 @@
 /** @file
   Platform PEI module include file.
 
-  Copyright (c) 2006 - 2007, Intel Corporation. All rights reserved.<BR>
+  Copyright (c) 2006 - 2011, Intel Corporation. All rights reserved.<BR>
   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
@@ -45,6 +45,12 @@ AddUntestedMemoryBaseSizeHob (
   UINT64                      MemorySize
   );
 
+VOID
+AddReservedMemoryBaseSizeHob (
+  EFI_PHYSICAL_ADDRESS        MemoryBase,
+  UINT64                      MemorySize
+  );
+
 VOID
 AddUntestedMemoryRangeHob (
   EFI_PHYSICAL_ADDRESS        MemoryBase,
@@ -61,4 +67,9 @@ PeiFvInitialization (
   VOID
   );
 
+EFI_STATUS
+InitializeXen (
+  VOID
+  );
+
 #endif // _PLATFORM_PEI_H_INCLUDED_