ArmPkg: Implement PeiServicesTablePointerLib using TPIDRURW register

This implementation use the Tpidrurw software context register to
store the PEI Services Table Pointer.

The author of this patch is Eugene Cohen (HP).



git-svn-id: https://edk2.svn.sourceforge.net/svnroot/edk2/trunk/edk2@11750 6f19259b-4bc3-4df7-8a09-765794883524

ArmPkg/Library/ArmLib/ArmV7/ArmV7Support.asm

@@ -50,6 +50,8 @@
     EXPORT  ArmReadCbar
     EXPORT  ArmInvalidateInstructionAndDataTlb
     EXPORT  ArmReadMpidr
+    EXPORT  ArmReadTpidrurw
+    EXPORT  ArmWriteTpidrurw
 
     AREA    ArmCacheLib, CODE, READONLY
     PRESERVE8
@@ -343,5 +345,13 @@ ArmReadMpidr
   mrc     p15, 0, r0, c0, c0, 5    ; read MPIDR
   bx      lr
 
+ArmReadTpidrurw
+  mrc     p15, 0, r0, c13, c0, 2    ; read TPIDRURW
+  bx      lr
+
+ArmWriteTpidrurw
+  mcr     p15, 0, r0, c13, c0, 2    ; write TPIDRURW
+  bx      lr
+
   END