[PATCH 1/2] UefiCpuPkg/MpInitLib: save/restore original contents

[Jeff Fan <jeff.fan@intel.com>]

If APs is in HLT-LOOP mode, we need AP reset vector for waking up APs. This
updating is to save/restore original contents of AP reset vector around waking
up APs always.

https://bugzilla.tianocore.org/show_bug.cgi?id=500

Cc: Feng Tian <feng.tian@intel.com>
Cc: Michael Kinney <michael.d.kinney@intel.com>
Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Jeff Fan <jeff.fan@intel.com>
---
 UefiCpuPkg/Library/MpInitLib/PeiMpLib.c | 16 ++++------------
 1 file changed, 4 insertions(+), 12 deletions(-)

diff --git a/UefiCpuPkg/Library/MpInitLib/PeiMpLib.c b/UefiCpuPkg/Library/MpInitLib/PeiMpLib.c
index fb1d48f..5ce5788 100644
--- a/UefiCpuPkg/Library/MpInitLib/PeiMpLib.c
+++ b/UefiCpuPkg/Library/MpInitLib/PeiMpLib.c
@@ -1,7 +1,7 @@
 /** @file
   MP initialize support functions for PEI phase.
 
-  Copyright (c) 2016, Intel Corporation. All rights reserved.<BR>
+  Copyright (c) 2016 - 2017, 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
@@ -129,10 +129,8 @@ CpuMpEndOfPeiCallback (
       }
       Hob.Raw = GET_NEXT_HOB (Hob);
     }
-  } else {
-    CpuMpData->SaveRestoreFlag = TRUE;
-    RestoreWakeupBuffer (CpuMpData);
   }
+
   return EFI_SUCCESS;
 }
 
@@ -286,12 +284,8 @@ AllocateResetVector (
     CpuMpData->WakeupBuffer      = GetWakeupBuffer (ApResetVectorSize);
     CpuMpData->MpCpuExchangeInfo = (MP_CPU_EXCHANGE_INFO *) (UINTN)
                     (CpuMpData->WakeupBuffer + CpuMpData->AddressMap.RendezvousFunnelSize);
-    BackupAndPrepareWakeupBuffer (CpuMpData);
-  }
-
-  if (CpuMpData->SaveRestoreFlag) {
-    BackupAndPrepareWakeupBuffer (CpuMpData);
   }
+  BackupAndPrepareWakeupBuffer (CpuMpData);
 }
 
 /**
@@ -304,9 +298,7 @@ FreeResetVector (
   IN CPU_MP_DATA              *CpuMpData
   )
 {
-  if (CpuMpData->SaveRestoreFlag) {
-    RestoreWakeupBuffer (CpuMpData);
-  }
+  RestoreWakeupBuffer (CpuMpData);
 }
 
 /**
-- 
2.9.3.windows.2