ArmPkg/ArmCpuLib: Replaced complex functions ArmCpuSynchronizeWait & ArmCpuSynchronizeSignal by sev & wfe

Previsouly the synchronization of MpCore was using the SGI (Software
Generated Interrupt) to synchronize MpCore during the early boot.
This commit replaced this mechanism by the more appropriate SEV/WFE
instructions (Send/Wait Event instructions).
That also eases the port to a new cpu/platform.

Signed-off-by: Olivier Martin <olivier.martin@arm.com>



git-svn-id: https://edk2.svn.sourceforge.net/svnroot/edk2/trunk/edk2@13249 6f19259b-4bc3-4df7-8a09-765794883524

ArmPlatformPkg/PrePi/PeiMPCore.inf

@@ -38,7 +38,6 @@
   BaseLib
   DebugLib
   DebugAgentLib
-  ArmCpuLib
   ArmLib
   ArmGicLib
   IoLib

ArmPlatformPkg/PrePi/PeiUniCore.inf

@@ -1,6 +1,7 @@
 #/** @file
 #  
-#  Copyright (c) 2011, ARM Ltd. All rights reserved.<BR>
+#  Copyright (c) 2011-2012, ARM Ltd. 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
@@ -38,7 +39,6 @@
   BaseLib
   DebugLib
   DebugAgentLib
-  ArmCpuLib
   ArmLib
   IoLib
   TimerLib

ArmPlatformPkg/PrePi/PrePi.c

@@ -14,7 +14,6 @@
 
 #include <PiPei.h>
 
-#include <Library/ArmCpuLib.h>
 #include <Library/DebugAgentLib.h>
 #include <Library/PrePiLib.h>
 #include <Library/PrintLib.h>
@@ -204,11 +203,12 @@ CEntryPoint (
     if (IS_PRIMARY_CORE(MpId)) {
       mGlobalVariableBase = GlobalVariableBase;
       if (ArmIsMpCore()) {
-        ArmCpuSynchronizeSignal (ARM_CPU_EVENT_DEFAULT);
+        // Signal the Global Variable Region is defined (event: ARM_CPU_EVENT_DEFAULT)
+        ArmCallSEV ();
       }
     } else {
-      // Wait the Primay core has defined the address of the Global Variable region
-      ArmCpuSynchronizeWait (ARM_CPU_EVENT_DEFAULT);
+      // Wait the Primay core has defined the address of the Global Variable region (event: ARM_CPU_EVENT_DEFAULT)
+      ArmCallWFE ();
     }
   }