EmulatorPkg/Sec/Ia32/TempRam.c

   1 /*++ @file
   2   Temp RAM PPI
   3
   4 Copyright (c) 2011, Apple Inc. All rights reserved.<BR>
   5 This program and the accompanying materials
   6 are licensed and made available under the terms and conditions of the BSD License
   7 which accompanies this distribution.  The full text of the license may be found at
   8 http://opensource.org/licenses/bsd-license.php
   9
  10 THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
  11 WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
  12
  13 **/
  14
  15 #include <PiPei.h>
  16 #include <Library/DebugLib.h>
  17 #include <Library/BaseMemoryLib.h>
  18
  19 #include <Ppi/TemporaryRamSupport.h>
  20
  21 VOID
  22 EFIAPI
  23 SecSwitchStack (
  24   UINT32   TemporaryMemoryBase,
  25   UINT32   PermenentMemoryBase
  26   );
  27
  28
  29 EFI_STATUS
  30 EFIAPI
  31 SecTemporaryRamSupport (
  32   IN CONST EFI_PEI_SERVICES   **PeiServices,
  33   IN EFI_PHYSICAL_ADDRESS     TemporaryMemoryBase,
  34   IN EFI_PHYSICAL_ADDRESS     PermanentMemoryBase,
  35   IN UINTN                    CopySize
  36   )
  37 {
  38   //
  39   // Migrate the whole temporary memory to permanent memory.
  40   //
  41   CopyMem (
  42     (VOID*)(UINTN)PermanentMemoryBase,
  43     (VOID*)(UINTN)TemporaryMemoryBase,
  44     CopySize
  45     );
  46
  47   //
  48   // SecSwitchStack function must be invoked after the memory migration
  49   // immediately, also we need fixup the stack change caused by new call into
  50   // permanent memory.
  51   //
  52   SecSwitchStack ((UINT32) TemporaryMemoryBase, (UINT32) PermanentMemoryBase);
  53
  54   //
  55   // We need *not* fix the return address because currently,
  56   // The PeiCore is executed in flash.
  57   //
  58
  59   //
  60   // Simulate to invalid temporary memory, terminate temporary memory
  61   //
  62   //ZeroMem ((VOID*)(UINTN)TemporaryMemoryBase, CopySize);
  63
  64   return EFI_SUCCESS;
  65 }