MdePkg/Library/UefiDriverEntryPoint/DriverEntryPoint.c

   1 /** @file
   2   Entry point to a EFI/DXE driver.
   3
   4 Copyright (c) 2006 - 2008, Intel Corporation. All rights reserved.<BR>
   5 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
  16
  17 #include <Uefi.h>
  18
  19 #include <Protocol/LoadedImage.h>
  20
  21 #include <Library/UefiDriverEntryPoint.h>
  22 #include <Library/DebugLib.h>
  23 #include <Library/UefiBootServicesTableLib.h>
  24
  25
  26 /**
  27   Unload function that is registered in the LoadImage protocol.  It un-installs
  28   protocols produced and deallocates pool used by the driver.  Called by the core
  29   when unloading the driver.
  30
  31   @param  ImageHandle ImageHandle of the loaded driver.
  32
  33   @return Status returned by all unload().
  34
  35 **/
  36 EFI_STATUS
  37 EFIAPI
  38 _DriverUnloadHandler (
  39   EFI_HANDLE ImageHandle
  40   )
  41 {
  42   EFI_STATUS  Status;
  43
  44   //
  45   // If an UnloadImage() handler is specified, then call it
  46   //
  47   Status = ProcessModuleUnloadList (ImageHandle);
  48
  49   //
  50   // If the driver specific unload handler does not return an error, then call all of the
  51   // library destructors.  If the unload handler returned an error, then the driver can not be
  52   // unloaded, and the library destructors should not be called
  53   //
  54   if (!EFI_ERROR (Status)) {
  55     ProcessLibraryDestructorList (ImageHandle, gST);
  56   }
  57
  58   //
  59   // Return the status from the driver specific unload handler
  60   //
  61   return Status;
  62 }
  63
  64
  65 /**
  66   The entry point of PE/COFF Image for a DXE Driver, DXE Runtime Driver, DXE SMM
  67   Driver, or UEFI Driver.
  68
  69   This function is the entry point for a DXE Driver, DXE Runtime Driver, DXE SMM Driver,
  70   or UEFI Driver.  This function must call ProcessLibraryConstructorList() and
  71   ProcessModuleEntryPointList(). If the return status from ProcessModuleEntryPointList()
  72   is an error status, then ProcessLibraryDestructorList() must be called. The return
  73   value from ProcessModuleEntryPointList() is returned. If _gDriverUnloadImageCount
  74   is greater than zero, then an unload handler must be registered for this image
  75   and the unload handler must invoke ProcessModuleUnloadList().
  76   If _gUefiDriverRevision is not zero and SystemTable->Hdr.Revision is less than
  77   _gUefiDriverRevison, then return EFI_INCOMPATIBLE_VERSION.
  78
  79
  80   @param  ImageHandle  The image handle of the DXE Driver, DXE Runtime Driver,
  81                        DXE SMM Driver, or UEFI Driver.
  82   @param  SystemTable  A pointer to the EFI System Table.
  83
  84   @retval  EFI_SUCCESS               The DXE Driver, DXE Runtime Driver, DXE SMM
  85                                      Driver, or UEFI Driver exited normally.
  86   @retval  EFI_INCOMPATIBLE_VERSION  _gUefiDriverRevision is greater than
  87                                     SystemTable->Hdr.Revision.
  88   @retval  Other                     Return value from ProcessModuleEntryPointList().
  89
  90 **/
  91 EFI_STATUS
  92 EFIAPI
  93 _ModuleEntryPoint (
  94   IN EFI_HANDLE        ImageHandle,
  95   IN EFI_SYSTEM_TABLE  *SystemTable
  96   )
  97 {
  98   EFI_STATUS                 Status;
  99   EFI_LOADED_IMAGE_PROTOCOL  *LoadedImage;
 100
 101   if (_gUefiDriverRevision != 0) {
 102     //
 103     // Make sure that the EFI/UEFI spec revision of the platform is >= EFI/UEFI spec revision of the driver
 104     //
 105     if (SystemTable->Hdr.Revision < _gUefiDriverRevision) {
 106       return EFI_INCOMPATIBLE_VERSION;
 107     }
 108   }
 109
 110   //
 111   // Call constructor for all libraries
 112   //
 113   ProcessLibraryConstructorList (ImageHandle, SystemTable);
 114
 115   //
 116   //  Install unload handler...
 117   //
 118   if (_gDriverUnloadImageCount != 0) {
 119     Status = gBS->HandleProtocol (
 120                     ImageHandle,
 121                     &gEfiLoadedImageProtocolGuid,
 122                     (VOID **)&LoadedImage
 123                     );
 124     ASSERT_EFI_ERROR (Status);
 125     LoadedImage->Unload = _DriverUnloadHandler;
 126   }
 127
 128   //
 129   // Call the driver entry point
 130   //
 131   Status = ProcessModuleEntryPointList (ImageHandle, SystemTable);
 132
 133   //
 134   // If all of the drivers returned errors, then invoke all of the library destructors
 135   //
 136   if (EFI_ERROR (Status)) {
 137     ProcessLibraryDestructorList (ImageHandle, SystemTable);
 138   }
 139
 140   //
 141   // Return the cummalative return status code from all of the driver entry points
 142   //
 143   return Status;
 144 }
 145
 146
 147 /**
 148   Required by the EBC compiler and identical in functionality to _ModuleEntryPoint().
 149
 150   This function is required to call _ModuleEntryPoint() passing in ImageHandle,
 151   and SystemTable.
 152
 153   @param  ImageHandle  The image handle of the DXE Driver, DXE Runtime Driver, DXE
 154                        SMM Driver, or UEFI Driver.
 155   @param  SystemTable  A pointer to the EFI System Table.
 156
 157   @retval  EFI_SUCCESS               The DXE Driver, DXE Runtime Driver, DXE SMM
 158                                      Driver, or UEFI Driver exited normally.
 159   @retval  EFI_INCOMPATIBLE_VERSION  _gUefiDriverRevision is greater than
 160                                      SystemTable->Hdr.Revision.
 161   @retval  Other                     Return value from ProcessModuleEntryPointList().
 162 **/
 163 EFI_STATUS
 164 EFIAPI
 165 EfiMain (
 166   IN EFI_HANDLE        ImageHandle,
 167   IN EFI_SYSTEM_TABLE  *SystemTable
 168   )
 169 {
 170   return _ModuleEntryPoint (ImageHandle, SystemTable);
 171 }