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diff --git a/OvmfPkg/XenPlatformPei/AmdSev.c b/OvmfPkg/XenPlatformPei/AmdSev.c
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+/**@file
+ Initialize Secure Encrypted Virtualization (SEV) support
+
+ Copyright (c) 2017, Advanced Micro Devices. All rights reserved.<BR>
+ Copyright (c) 2019, Citrix Systems, Inc.
+
+ SPDX-License-Identifier: BSD-2-Clause-Patent
+
+**/
+//
+// The package level header files this module uses
+//
+#include <Library/DebugLib.h>
+#include <Library/MemEncryptSevLib.h>
+#include <Library/PcdLib.h>
+#include <PiPei.h>
+#include <Register/Amd/Cpuid.h>
+#include <Register/Cpuid.h>
+
+#include "Platform.h"
+
+/**
+
+ Function checks if SEV support is available, if present then it sets
+ the dynamic PcdPteMemoryEncryptionAddressOrMask with memory encryption mask.
+
+ **/
+VOID
+AmdSevInitialize (
+ VOID
+ )
+{
+ CPUID_MEMORY_ENCRYPTION_INFO_EBX Ebx;
+ UINT64 EncryptionMask;
+ RETURN_STATUS PcdStatus;
+
+ //
+ // Check if SEV is enabled
+ //
+ if (!MemEncryptSevIsEnabled ()) {
+ return;
+ }
+
+ //
+ // CPUID Fn8000_001F[EBX] Bit 0:5 (memory encryption bit position)
+ //
+ AsmCpuid (CPUID_MEMORY_ENCRYPTION_INFO, NULL, &Ebx.Uint32, NULL, NULL);
+ EncryptionMask = LShiftU64 (1, Ebx.Bits.PtePosBits);
+
+ //
+ // Set Memory Encryption Mask PCD
+ //
+ PcdStatus = PcdSet64S (PcdPteMemoryEncryptionAddressOrMask, EncryptionMask);
+ ASSERT_RETURN_ERROR (PcdStatus);
+
+ DEBUG ((DEBUG_INFO, "SEV is enabled (mask 0x%lx)\n", EncryptionMask));
+
+ //
+ // Set Pcd to Deny the execution of option ROM when security
+ // violation.
+ //
+ PcdStatus = PcdSet32S (PcdOptionRomImageVerificationPolicy, 0x4);
+ ASSERT_RETURN_ERROR (PcdStatus);
+}