MdeModulePkg/Core/DxeIplPeim/Ebc/DxeLoadFunc.c

   1 /** @file
   2   EBC-specific functionality for DxeLoad.
   3
   4 Copyright (c) 2006 - 2018, Intel Corporation. All rights reserved.<BR>
   5 SPDX-License-Identifier: BSD-2-Clause-Patent
   6
   7 **/
   8
   9 #include "DxeIpl.h"
  10
  11 /**
  12    Transfers control to DxeCore.
  13
  14    This function performs a CPU architecture specific operations to execute
  15    the entry point of DxeCore with the parameters of HobList.
  16    It also installs EFI_END_OF_PEI_PPI to signal the end of PEI phase.
  17
  18    @param DxeCoreEntryPoint         The entry point of DxeCore.
  19    @param HobList                   The start of HobList passed to DxeCore.
  20
  21 **/
  22 VOID
  23 HandOffToDxeCore (
  24   IN EFI_PHYSICAL_ADDRESS  DxeCoreEntryPoint,
  25   IN EFI_PEI_HOB_POINTERS  HobList
  26   )
  27 {
  28   VOID        *BaseOfStack;
  29   VOID        *TopOfStack;
  30   EFI_STATUS  Status;
  31
  32   //
  33   // Allocate 128KB for the Stack
  34   //
  35   BaseOfStack = AllocatePages (EFI_SIZE_TO_PAGES (STACK_SIZE));
  36   ASSERT (BaseOfStack != NULL);
  37
  38   //
  39   // Compute the top of the stack we were allocated. Pre-allocate a UINTN
  40   // for safety.
  41   //
  42   TopOfStack = (VOID *)((UINTN)BaseOfStack + EFI_SIZE_TO_PAGES (STACK_SIZE) * EFI_PAGE_SIZE - CPU_STACK_ALIGNMENT);
  43   TopOfStack = ALIGN_POINTER (TopOfStack, CPU_STACK_ALIGNMENT);
  44
  45   //
  46   // End of PEI phase signal
  47   //
  48   Status = PeiServicesInstallPpi (&gEndOfPeiSignalPpi);
  49   ASSERT_EFI_ERROR (Status);
  50
  51   //
  52   // Update the contents of BSP stack HOB to reflect the real stack info passed to DxeCore.
  53   //
  54   UpdateStackHob ((EFI_PHYSICAL_ADDRESS)(UINTN)BaseOfStack, STACK_SIZE);
  55
  56   //
  57   // Transfer the control to the entry point of DxeCore.
  58   //
  59   SwitchStack (
  60     (SWITCH_STACK_ENTRY_POINT)(UINTN)DxeCoreEntryPoint,
  61     HobList.Raw,
  62     NULL,
  63     TopOfStack
  64     );
  65 }