OvmfPkg/Library/PlatformHasIoMmuLib/PlatformHasIoMmuLib.c

   1 /** @file
   2   A hook-in library for MdeModulePkg/Bus/Pci/PciHostBridgeDxe.
   3
   4   Plugging this library instance into PciHostBridgeDxe makes
   5   PciHostBridgeDxe depend on the platform's dynamic decision whether
   6   to provide IOMMU implementation (usually through IoMmuDxe driver).
   7
   8   Copyright (C) 2017, Red Hat, Inc.
   9   Copyright (C) 2017, AMD, Inc.
  10
  11   SPDX-License-Identifier: BSD-2-Clause-Patent
  12 **/
  13
  14 #include <Base.h>
  15
  16 RETURN_STATUS
  17 EFIAPI
  18 PlatformHasIoMmuInitialize (
  19   VOID
  20   )
  21 {
  22   //
  23   // Do nothing, just imbue PciHostBridgeDxe with a protocol dependency on
  24   // gIoMmuAbsentProtocolGuid OR gEdkiiIoMmuProtocolGuid.
  25   //
  26   return RETURN_SUCCESS;
  27 }