OvmfPkg/PlatformInitLib: catch QEMU's CPU hotplug reg block regression

[mirror_edk2.git] / OvmfPkg / Library / UefiDriverEntryPointFwCfgOverrideLib / UefiDriverEntryPointFwCfgOverrideLib.c

/** @file\r
  Entry point to a EFI/DXE driver. This version is specific to QEMU, and ties\r
  dispatch of the driver in question on the value of a QEMU fw_cfg boolean\r
  variable which is referenced by name via a fixed pointer PCD.\r
\r
Copyright (c) 2006 - 2018, Intel Corporation. All rights reserved.<BR>\r
Copyright (c) 2022, Google LLC. All rights reserved.<BR>\r
SPDX-License-Identifier: BSD-2-Clause-Patent\r
\r
**/\r
\r
#include <Uefi.h>\r
\r
#include <Protocol/LoadedImage.h>\r
\r
#include <Library/BaseLib.h>\r
#include <Library/DebugLib.h>\r
#include <Library/QemuFwCfgSimpleParserLib.h>\r
#include <Library/UefiBootServicesTableLib.h>\r
#include <Library/UefiDriverEntryPoint.h>\r
\r
/**\r
  Unloads an image from memory.\r
\r
  This function is a callback that a driver registers to do cleanup\r
  when the UnloadImage boot service function is called.\r
\r
  @param  ImageHandle The handle to the image to unload.\r
\r
  @return Status returned by all unload().\r
\r
**/\r
STATIC\r
EFI_STATUS\r
EFIAPI\r
_DriverUnloadHandler (\r
  EFI_HANDLE  ImageHandle\r
  )\r
{\r
  EFI_STATUS  Status;\r
\r
  //\r
  // If an UnloadImage() handler is specified, then call it\r
  //\r
  Status = ProcessModuleUnloadList (ImageHandle);\r
\r
  //\r
  // If the driver specific unload handler does not return an error, then call\r
  // all of the library destructors.  If the unload handler returned an error,\r
  // then the driver can not be unloaded, and the library destructors should\r
  // not be called\r
  //\r
  if (!EFI_ERROR (Status)) {\r
    ProcessLibraryDestructorList (ImageHandle, gST);\r
  }\r
\r
  //\r
  // Return the status from the driver specific unload handler\r
  //\r
  return Status;\r
}\r
\r
/**\r
  The entry point of PE/COFF Image for a DXE Driver, DXE Runtime Driver, or\r
  UEFI Driver.\r
\r
  @param  ImageHandle                The image handle of the DXE Driver, DXE\r
                                     Runtime Driver, or UEFI Driver.\r
  @param  SystemTable                A pointer to the EFI System Table.\r
\r
  @retval  EFI_SUCCESS               The DXE Driver, DXE Runtime Driver, or\r
                                     UEFI Driver exited normally.\r
  @retval  EFI_INCOMPATIBLE_VERSION  _gUefiDriverRevision is greater than\r
                                     SystemTable->Hdr.Revision.\r
  @retval  Other                     Return value from\r
                                     ProcessModuleEntryPointList().\r
\r
**/\r
EFI_STATUS\r
EFIAPI\r
_ModuleEntryPoint (\r
  IN EFI_HANDLE        ImageHandle,\r
  IN EFI_SYSTEM_TABLE  *SystemTable\r
  )\r
{\r
  EFI_STATUS                 Status;\r
  EFI_LOADED_IMAGE_PROTOCOL  *LoadedImage;\r
  RETURN_STATUS              RetStatus;\r
  BOOLEAN                    Enabled;\r
\r
  if (_gUefiDriverRevision != 0) {\r
    //\r
    // Make sure that the EFI/UEFI spec revision of the platform is >= EFI/UEFI\r
    // spec revision of the driver\r
    //\r
    if (SystemTable->Hdr.Revision < _gUefiDriverRevision) {\r
      return EFI_INCOMPATIBLE_VERSION;\r
    }\r
  }\r
\r
  //\r
  // Call constructor for all libraries\r
  //\r
  ProcessLibraryConstructorList (ImageHandle, SystemTable);\r
\r
  //\r
  //  Install unload handler...\r
  //\r
  if (_gDriverUnloadImageCount != 0) {\r
    Status = gBS->HandleProtocol (\r
                    ImageHandle,\r
                    &gEfiLoadedImageProtocolGuid,\r
                    (VOID **)&LoadedImage\r
                    );\r
    ASSERT_EFI_ERROR (Status);\r
    LoadedImage->Unload = _DriverUnloadHandler;\r
  }\r
\r
  RetStatus = QemuFwCfgParseBool (\r
                FixedPcdGetPtr (PcdEntryPointOverrideFwCfgVarName),\r
                &Enabled\r
                );\r
  if (!RETURN_ERROR (RetStatus) && !Enabled) {\r
    //\r
    // The QEMU fw_cfg variable tells us not to load this image.  So abort.\r
    //\r
    Status = EFI_ABORTED;\r
  } else {\r
    //\r
    // Call the driver entry point\r
    //\r
    Status = ProcessModuleEntryPointList (ImageHandle, SystemTable);\r
  }\r
\r
  //\r
  // If all of the drivers returned errors, or we if are aborting, then invoke\r
  // all of the library destructors\r
  //\r
  if (EFI_ERROR (Status)) {\r
    ProcessLibraryDestructorList (ImageHandle, SystemTable);\r
  }\r
\r
  //\r
  // Return the cumulative return status code from all of the driver entry\r
  // points\r
  //\r
  return Status;\r
}\r