OvmfPkg/AcpiPlatformDxe/EntryPoint.c

   1 /** @file
   2   Entry point of OVMF ACPI Platform Driver
   3
   4   Copyright (C) 2015, Red Hat, Inc.
   5   Copyright (c) 2008 - 2015, Intel Corporation. All rights reserved.<BR>
   6
   7   This program and the accompanying materials are licensed and made available
   8   under the terms and conditions of the BSD License which accompanies this
   9   distribution.  The full text of the license may be found at
  10   http://opensource.org/licenses/bsd-license.php
  11
  12   THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS, WITHOUT
  13   WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
  14 **/
  15
  16 #include <Guid/RootBridgesConnectedEventGroup.h>
  17 #include "AcpiPlatform.h"
  18
  19 STATIC
  20 EFI_ACPI_TABLE_PROTOCOL *
  21 FindAcpiTableProtocol (
  22   VOID
  23   )
  24 {
  25   EFI_STATUS              Status;
  26   EFI_ACPI_TABLE_PROTOCOL *AcpiTable;
  27
  28   Status = gBS->LocateProtocol (
  29                   &gEfiAcpiTableProtocolGuid,
  30                   NULL,
  31                   (VOID**)&AcpiTable
  32                   );
  33   ASSERT_EFI_ERROR (Status);
  34   return AcpiTable;
  35 }
  36
  37
  38 STATIC
  39 VOID
  40 EFIAPI
  41 OnRootBridgesConnected (
  42   IN EFI_EVENT Event,
  43   IN VOID      *Context
  44   )
  45 {
  46   EFI_STATUS Status;
  47
  48   DEBUG ((EFI_D_INFO,
  49     "%a: root bridges have been connected, installing ACPI tables\n",
  50     __FUNCTION__));
  51   Status = InstallAcpiTables (FindAcpiTableProtocol ());
  52   if (EFI_ERROR (Status)) {
  53     DEBUG ((EFI_D_ERROR, "%a: InstallAcpiTables: %r\n", __FUNCTION__, Status));
  54   }
  55   gBS->CloseEvent (Event);
  56 }
  57
  58
  59 EFI_STATUS
  60 EFIAPI
  61 AcpiPlatformEntryPoint (
  62   IN EFI_HANDLE         ImageHandle,
  63   IN EFI_SYSTEM_TABLE   *SystemTable
  64   )
  65 {
  66   EFI_STATUS Status;
  67   EFI_EVENT  RootBridgesConnected;
  68
  69   //
  70   // If the platform doesn't support PCI, or PCI enumeration has been disabled,
  71   // install the tables at once, and let the entry point's return code reflect
  72   // the full functionality.
  73   //
  74   if (PcdGetBool (PcdPciDisableBusEnumeration)) {
  75     DEBUG ((EFI_D_INFO, "%a: PCI or its enumeration disabled, installing "
  76       "ACPI tables\n", __FUNCTION__));
  77     return InstallAcpiTables (FindAcpiTableProtocol ());
  78   }
  79
  80   //
  81   // Otherwise, delay installing the ACPI tables until root bridges are
  82   // connected. The entry point's return status will only reflect the callback
  83   // setup. (Note that we're a DXE_DRIVER; our entry point function is invoked
  84   // strictly before BDS is entered and can connect the root bridges.)
  85   //
  86   Status = gBS->CreateEventEx (EVT_NOTIFY_SIGNAL, TPL_CALLBACK,
  87                   OnRootBridgesConnected, NULL /* Context */,
  88                   &gRootBridgesConnectedEventGroupGuid, &RootBridgesConnected);
  89   if (!EFI_ERROR (Status)) {
  90     DEBUG ((EFI_D_INFO,
  91       "%a: waiting for root bridges to be connected, registered callback\n",
  92       __FUNCTION__));
  93   }
  94
  95   return Status;
  96 }