MdePkg/Library/UefiRuntimeLib/RuntimeLib.c

   1 /** @file
   2   UEFI Runtime Library implementation for non IPF processor types.
   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 "RuntimeLibInternal.h"
  16
  17 ///
  18 /// Driver Lib Module Globals
  19 ///
  20
  21 EFI_EVENT              mEfiVirtualNotifyEvent;
  22 EFI_EVENT              mEfiExitBootServicesEvent;
  23 BOOLEAN                mEfiGoneVirtual         = FALSE;
  24 BOOLEAN                mEfiAtRuntime           = FALSE;
  25 EFI_RUNTIME_SERVICES   *mRT;
  26
  27 /**
  28   Set AtRuntime flag as TRUE after ExitBootServices.
  29
  30   @param[in]  Event   The Event that is being processed
  31   @param[in]  Context Event Context
  32 **/
  33 VOID
  34 EFIAPI
  35 RuntimeLibExitBootServicesEvent (
  36   IN EFI_EVENT        Event,
  37   IN VOID             *Context
  38   )
  39 {
  40   //
  41   // Clear out BootService globals
  42   //
  43   gBS             = NULL;
  44
  45   mEfiAtRuntime = TRUE;
  46 }
  47
  48 /**
  49   Fixup internal data so that EFI can be call in virtual mode.
  50   Call the passed in Child Notify event and convert any pointers in
  51   lib to virtual mode.
  52
  53   @param[in]    Event   The Event that is being processed
  54   @param[in]    Context Event Context
  55 **/
  56 VOID
  57 EFIAPI
  58 RuntimeLibVirtualNotifyEvent (
  59   IN EFI_EVENT        Event,
  60   IN VOID             *Context
  61   )
  62 {
  63   //
  64   // Update global for Runtime Services Table and IO
  65   //
  66   EfiConvertPointer (0, (VOID **) &mRT);
  67
  68   mEfiGoneVirtual = TRUE;
  69 }
  70
  71 /**
  72   Initialize runtime Driver Lib if it has not yet been initialized.
  73   It will ASSERT() if gRT is NULL or gBS is NULL.
  74   It will ASSERT() if that operation fails.
  75
  76   @param[in]  ImageHandle   The firmware allocated handle for the EFI image.
  77   @param[in]  SystemTable   A pointer to the EFI System Table.
  78
  79   @return     EFI_STATUS    always returns EFI_SUCCESS except EFI_ALREADY_STARTED if already started.
  80 **/
  81 EFI_STATUS
  82 EFIAPI
  83 RuntimeDriverLibConstruct (
  84   IN EFI_HANDLE           ImageHandle,
  85   IN EFI_SYSTEM_TABLE     *SystemTable
  86   )
  87 {
  88   EFI_STATUS  Status;
  89
  90   ASSERT (gRT != NULL);
  91   ASSERT (gBS != NULL);
  92
  93   mRT = gRT;
  94   //
  95   // Register SetVirtualAddressMap () notify function
  96   //
  97   Status = gBS->CreateEventEx (
  98                   EVT_NOTIFY_SIGNAL,
  99                   TPL_NOTIFY,
 100                   RuntimeLibVirtualNotifyEvent,
 101                   NULL,
 102                   &gEfiEventVirtualAddressChangeGuid,
 103                   &mEfiVirtualNotifyEvent
 104                   );
 105
 106   ASSERT_EFI_ERROR (Status);
 107
 108   Status = gBS->CreateEventEx (
 109                   EVT_NOTIFY_SIGNAL,
 110                   TPL_NOTIFY,
 111                   RuntimeLibExitBootServicesEvent,
 112                   NULL,
 113                   &gEfiEventExitBootServicesGuid,
 114                   &mEfiExitBootServicesEvent
 115                   );
 116
 117   ASSERT_EFI_ERROR (Status);
 118
 119   return Status;
 120 }
 121
 122 /**
 123   If a runtime driver exits with an error, it must call this routine
 124   to free the allocated resource before the exiting.
 125   It will ASSERT() if gBS is NULL.
 126   It will ASSERT() if that operation fails.
 127
 128   @param[in]  ImageHandle   The firmware allocated handle for the EFI image.
 129   @param[in]  SystemTable   A pointer to the EFI System Table.
 130
 131   @retval     EFI_SUCCESS       Shutdown the Runtime Driver Lib successfully
 132   @retval     EFI_UNSUPPORTED   Runtime Driver lib was not initialized at all
 133 **/
 134 EFI_STATUS
 135 EFIAPI
 136 RuntimeDriverLibDeconstruct (
 137   IN EFI_HANDLE        ImageHandle,
 138   IN EFI_SYSTEM_TABLE  *SystemTable
 139   )
 140 {
 141   EFI_STATUS  Status;
 142
 143   //
 144   // Close SetVirtualAddressMap () notify function
 145   //
 146   ASSERT (gBS != NULL);
 147   Status = gBS->CloseEvent (mEfiVirtualNotifyEvent);
 148   ASSERT_EFI_ERROR (Status);
 149
 150   Status = gBS->CloseEvent (mEfiExitBootServicesEvent);
 151   ASSERT_EFI_ERROR (Status);
 152
 153   return Status;
 154 }
 155
 156 /**
 157   This function allows the caller to determine if UEFI ExitBootServices() has been called.
 158
 159   This function returns TRUE after all the EVT_SIGNAL_EXIT_BOOT_SERVICES functions have
 160   executed as a result of the OS calling ExitBootServices().  Prior to this time FALSE
 161   is returned. This function is used by runtime code to decide it is legal to access
 162   services that go away after ExitBootServices().
 163
 164   @retval  TRUE  The system has finished executing the EVT_SIGNAL_EXIT_BOOT_SERVICES event.
 165   @retval  FALSE The system has not finished executing the EVT_SIGNAL_EXIT_BOOT_SERVICES event.
 166
 167 **/
 168 BOOLEAN
 169 EFIAPI
 170 EfiAtRuntime (
 171   VOID
 172   )
 173 {
 174   return mEfiAtRuntime;
 175 }
 176
 177 /**
 178   This function allows the caller to determine if UEFI SetVirtualAddressMap() has been called.
 179
 180   This function returns TRUE after all the EVT_SIGNAL_VIRTUAL_ADDRESS_CHANGE functions have
 181   executed as a result of the OS calling SetVirtualAddressMap(). Prior to this time FALSE
 182   is returned. This function is used by runtime code to decide it is legal to access services
 183   that go away after SetVirtualAddressMap().
 184
 185   @retval  TRUE  The system has finished executing the EVT_SIGNAL_VIRTUAL_ADDRESS_CHANGE event.
 186   @retval  FALSE The system has not finished executing the EVT_SIGNAL_VIRTUAL_ADDRESS_CHANGE event.
 187
 188 **/
 189 BOOLEAN
 190 EFIAPI
 191 EfiGoneVirtual (
 192   VOID
 193   )
 194 {
 195   return mEfiGoneVirtual;
 196 }
 197