ArmPlatformPkg: Change the memory model for the ARM Platform components

In the former memory model, the UEFI firmware was expected to be located
at the top of the system memory. Stacks & Pi memory regions were set below
the firmware.
On some platform, the UEFI firmware could be shadowed by the ROM firmware
(case of the BeagleBoard) and in some cases the firmware is copied at the
beginning of the system memory.

With this new memory model, stack and Pi/DXE memory regions are set at the
top of the system memory wherever the UEFI firmware is located in the memory
map.
Because DXE core does not support shadowed firmwares, the system memory covered
by the UEFI firmware is marked as 'Non Present' to avoid to be overlapped by
DXE allocations.



git-svn-id: https://edk2.svn.sourceforge.net/svnroot/edk2/trunk/edk2@11992 6f19259b-4bc3-4df7-8a09-765794883524

ArmPlatformPkg/PrePi/MainMPCore.c

@@ -21,20 +21,19 @@
 VOID
 PrimaryMain (
   IN  UINTN                     UefiMemoryBase,
-  IN  UINTN                     StackBase,
   IN  UINT64                    StartTimeStamp
   )
 {
   //Enable the GIC Distributor
   PL390GicEnableDistributor(PcdGet32(PcdGicDistributorBase));
 
-  // If ArmVe has not been built as Standalone then we need to wake up the secondary cores
-  if (!FixedPcdGet32(PcdStandalone)) {
+  // In some cases, the secondary cores are waiting for an SGI from the next stage boot loader toresume their initialization
+  if (!FixedPcdGet32(PcdSendSgiToBringUpSecondaryCores)) {
     // Sending SGI to all the Secondary CPU interfaces
     PL390GicSendSgiTo (PcdGet32(PcdGicDistributorBase), GIC_ICDSGIR_FILTER_EVERYONEELSE, 0x0E);
   }
 
-  PrePiMain (UefiMemoryBase, StackBase, StartTimeStamp);
+  PrePiMain (UefiMemoryBase, StartTimeStamp);
 
   // We must never return
   ASSERT(FALSE);