OvmfPkg/Library/SmmCpuPlatformHookLibQemu/SmmCpuPlatformHookLibQemu.c

   1 /** @file
   2 SMM CPU Platform Hook library instance for QEMU.
   3
   4 Copyright (c) 2020, Red Hat, Inc.
   5 Copyright (c) 2006 - 2015, Intel Corporation. All rights reserved.<BR>
   6 SPDX-License-Identifier: BSD-2-Clause-Patent
   7
   8 **/
   9 #include <PiSmm.h>
  10 #include <Library/SmmCpuPlatformHookLib.h>
  11
  12 /**
  13   Checks if platform produces a valid SMI.
  14
  15   This function checks if platform produces a valid SMI. This function is
  16   called at SMM entry to detect if this is a spurious SMI. This function
  17   must be implemented in an MP safe way because it is called by multiple CPU
  18   threads.
  19
  20   @retval TRUE              There is a valid SMI
  21   @retval FALSE             There is no valid SMI
  22
  23 **/
  24 BOOLEAN
  25 EFIAPI
  26 PlatformValidSmi (
  27   VOID
  28   )
  29 {
  30   return TRUE;
  31 }
  32
  33 /**
  34   Clears platform top level SMI status bit.
  35
  36   This function clears platform top level SMI status bit.
  37
  38   @retval TRUE              The platform top level SMI status is cleared.
  39   @retval FALSE             The platform top level SMI status cannot be
  40                             cleared.
  41
  42 **/
  43 BOOLEAN
  44 EFIAPI
  45 ClearTopLevelSmiStatus (
  46   VOID
  47   )
  48 {
  49   return TRUE;
  50 }
  51
  52 /**
  53   Performs platform specific way of SMM BSP election.
  54
  55   This function performs platform specific way of SMM BSP election.
  56
  57   @param  IsBsp             Output parameter. TRUE: the CPU this function
  58                             executes on is elected to be the SMM BSP. FALSE:
  59                             the CPU this function executes on is to be SMM AP.
  60
  61   @retval EFI_SUCCESS       The function executes successfully.
  62   @retval EFI_NOT_READY     The function does not determine whether this CPU
  63                             should be BSP or AP. This may occur if hardware
  64                             init sequence to enable the determination is yet to
  65                             be done, or the function chooses not to do BSP
  66                             election and will let SMM CPU driver to use its
  67                             default BSP election process.
  68   @retval EFI_DEVICE_ERROR  The function cannot determine whether this CPU
  69                             should be BSP or AP due to hardware error.
  70
  71 **/
  72 EFI_STATUS
  73 EFIAPI
  74 PlatformSmmBspElection (
  75   OUT BOOLEAN     *IsBsp
  76   )
  77 {
  78   return EFI_NOT_READY;
  79 }
  80
  81 /**
  82   Get platform page table attribute.
  83
  84   This function gets page table attribute of platform.
  85
  86   @param  Address        Input parameter. Obtain the page table entries
  87                          attribute on this address.
  88   @param  PageSize       Output parameter. The size of the page.
  89   @param  NumOfPages     Output parameter. Number of page.
  90   @param  PageAttribute  Output parameter. Paging Attributes (WB, UC, etc).
  91
  92   @retval EFI_SUCCESS      The platform page table attribute from the address
  93                            is determined.
  94   @retval EFI_UNSUPPORTED  The platform does not support getting page table
  95                            attribute for the address.
  96
  97 **/
  98 EFI_STATUS
  99 EFIAPI
 100 GetPlatformPageTableAttribute (
 101   IN  UINT64                Address,
 102   IN OUT SMM_PAGE_SIZE_TYPE *PageSize,
 103   IN OUT UINTN              *NumOfPages,
 104   IN OUT UINTN              *PageAttribute
 105   )
 106 {
 107   return EFI_UNSUPPORTED;
 108 }