MdeModulePkg/Core/DxeIplPeim/X64/DxeLoadFunc.c

   1 /** @file
   2   x64-specifc functionality for DxeLoad.
   3
   4 Copyright (c) 2006 - 2008, Intel Corporation. <BR>
   5 All rights reserved. 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 "DxeIpl.h"
  16 #include "X64/VirtualMemory.h"
  17
  18
  19
  20 /**
  21    Transfers control to DxeCore.
  22
  23    This function performs a CPU architecture specific operations to execute
  24    the entry point of DxeCore with the parameters of HobList.
  25    It also intalls EFI_END_OF_PEI_PPI to signal the end of PEI phase.
  26
  27    @param DxeCoreEntryPoint         The entrypoint of DxeCore.
  28    @param HobList                   The start of HobList passed to DxeCore.
  29
  30 **/
  31 VOID
  32 HandOffToDxeCore (
  33   IN EFI_PHYSICAL_ADDRESS   DxeCoreEntryPoint,
  34   IN EFI_PEI_HOB_POINTERS   HobList
  35   )
  36 {
  37   VOID                *BaseOfStack;
  38   VOID                *TopOfStack;
  39   EFI_STATUS          Status;
  40   UINTN               PageTables;
  41
  42   //
  43   // Allocate 128KB for the Stack
  44   //
  45   BaseOfStack = AllocatePages (EFI_SIZE_TO_PAGES (STACK_SIZE));
  46   ASSERT (BaseOfStack != NULL);
  47
  48   //
  49   // Compute the top of the stack we were allocated. Pre-allocate a UINTN
  50   // for safety.
  51   //
  52   TopOfStack = (VOID *) ((UINTN) BaseOfStack + EFI_SIZE_TO_PAGES (STACK_SIZE) * EFI_PAGE_SIZE - CPU_STACK_ALIGNMENT);
  53   TopOfStack = ALIGN_POINTER (TopOfStack, CPU_STACK_ALIGNMENT);
  54
  55   //
  56   // Create page table and save PageMapLevel4 to CR3
  57   //
  58   PageTables = CreateIdentityMappingPageTables ();
  59
  60   //
  61   // End of PEI phase singal
  62   //
  63   Status = PeiServicesInstallPpi (&gEndOfPeiSignalPpi);
  64   ASSERT_EFI_ERROR (Status);
  65
  66   AsmWriteCr3 (PageTables);
  67
  68   //
  69   // Update the contents of BSP stack HOB to reflect the real stack info passed to DxeCore.
  70   //
  71   UpdateStackHob ((EFI_PHYSICAL_ADDRESS)(UINTN) BaseOfStack, STACK_SIZE);
  72
  73   //
  74   // Transfer the control to the entry point of DxeCore.
  75   //
  76   SwitchStack (
  77     (SWITCH_STACK_ENTRY_POINT)(UINTN)DxeCoreEntryPoint,
  78     HobList.Raw,
  79     NULL,
  80     TopOfStack
  81     );
  82 }