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   Intialize 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->CreateEvent (
  98                   EVT_SIGNAL_VIRTUAL_ADDRESS_CHANGE,
  99                   TPL_NOTIFY,
 100                   RuntimeLibVirtualNotifyEvent,
 101                   NULL,
 102                   &mEfiVirtualNotifyEvent
 103                   );
 104
 105   ASSERT_EFI_ERROR (Status);
 106
 107   Status = gBS->CreateEvent (
 108                   EVT_SIGNAL_EXIT_BOOT_SERVICES,
 109                   TPL_NOTIFY,
 110                   RuntimeLibExitBootServicesEvent,
 111                   NULL,
 112                   &mEfiExitBootServicesEvent
 113                   );
 114
 115   ASSERT_EFI_ERROR (Status);
 116
 117   return Status;
 118 }
 119
 120 /**
 121   If a runtime driver exits with an error, it must call this routine
 122   to free the allocated resource before the exiting.
 123   It will ASSERT() if gBS is NULL.
 124   It will ASSERT() if that operation fails.
 125
 126   @param[in]  ImageHandle   The firmware allocated handle for the EFI image.
 127   @param[in]  SystemTable   A pointer to the EFI System Table.
 128
 129   @retval     EFI_SUCCESS       Shutdown the Runtime Driver Lib successfully
 130   @retval     EFI_UNSUPPORTED   Runtime Driver lib was not initialized at all
 131 **/
 132 EFI_STATUS
 133 EFIAPI
 134 RuntimeDriverLibDeconstruct (
 135   IN EFI_HANDLE        ImageHandle,
 136   IN EFI_SYSTEM_TABLE  *SystemTable
 137   )
 138 {
 139   EFI_STATUS  Status;
 140
 141   //
 142   // Close SetVirtualAddressMap () notify function
 143   //
 144   ASSERT (gBS != NULL);
 145   Status = gBS->CloseEvent (mEfiVirtualNotifyEvent);
 146   ASSERT_EFI_ERROR (Status);
 147
 148   Status = gBS->CloseEvent (mEfiExitBootServicesEvent);
 149   ASSERT_EFI_ERROR (Status);
 150
 151   return Status;
 152 }
 153
 154 /**
 155   This function allows the caller to determine if UEFI ExitBootServices() has been called.
 156
 157   This function returns TRUE after all the EVT_SIGNAL_EXIT_BOOT_SERVICES functions have
 158   executed as a result of the OS calling ExitBootServices().  Prior to this time FALSE
 159   is returned. This function is used by runtime code to decide it is legal to access
 160   services that go away after ExitBootServices().
 161
 162   @retval  TRUE  The system has finished executing the EVT_SIGNAL_EXIT_BOOT_SERVICES event.
 163   @retval  FALSE The system has not finished executing the EVT_SIGNAL_EXIT_BOOT_SERVICES event.
 164
 165 **/
 166 BOOLEAN
 167 EFIAPI
 168 EfiAtRuntime (
 169   VOID
 170   )
 171 {
 172   return mEfiAtRuntime;
 173 }
 174
 175 /**
 176   This function allows the caller to determine if UEFI SetVirtualAddressMap() has been called.
 177
 178   This function returns TRUE after all the EVT_SIGNAL_VIRTUAL_ADDRESS_CHANGE functions have
 179   executed as a result of the OS calling SetVirtualAddressMap(). Prior to this time FALSE
 180   is returned. This function is used by runtime code to decide it is legal to access services
 181   that go away after SetVirtualAddressMap().
 182
 183   @retval  TRUE  The system has finished executing the EVT_SIGNAL_VIRTUAL_ADDRESS_CHANGE event.
 184   @retval  FALSE The system has not finished executing the EVT_SIGNAL_VIRTUAL_ADDRESS_CHANGE event.
 185
 186 **/
 187 BOOLEAN
 188 EFIAPI
 189 EfiGoneVirtual (
 190   VOID
 191   )
 192 {
 193   return mEfiGoneVirtual;
 194 }
 195