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   SPDX-License-Identifier: BSD-2-Clause-Patent
   8 **/
   9
  10 #include <Guid/RootBridgesConnectedEventGroup.h>
  11 #include "AcpiPlatform.h"
  12
  13 STATIC
  14 EFI_ACPI_TABLE_PROTOCOL *
  15 FindAcpiTableProtocol (
  16   VOID
  17   )
  18 {
  19   EFI_STATUS              Status;
  20   EFI_ACPI_TABLE_PROTOCOL *AcpiTable;
  21
  22   Status = gBS->LocateProtocol (
  23                   &gEfiAcpiTableProtocolGuid,
  24                   NULL,
  25                   (VOID**)&AcpiTable
  26                   );
  27   ASSERT_EFI_ERROR (Status);
  28   return AcpiTable;
  29 }
  30
  31
  32 STATIC
  33 VOID
  34 EFIAPI
  35 OnRootBridgesConnected (
  36   IN EFI_EVENT Event,
  37   IN VOID      *Context
  38   )
  39 {
  40   EFI_STATUS Status;
  41
  42   DEBUG ((DEBUG_INFO,
  43     "%a: root bridges have been connected, installing ACPI tables\n",
  44     __FUNCTION__));
  45   Status = InstallAcpiTables (FindAcpiTableProtocol ());
  46   if (EFI_ERROR (Status)) {
  47     DEBUG ((DEBUG_ERROR, "%a: InstallAcpiTables: %r\n", __FUNCTION__, Status));
  48   }
  49   gBS->CloseEvent (Event);
  50 }
  51
  52
  53 EFI_STATUS
  54 EFIAPI
  55 AcpiPlatformEntryPoint (
  56   IN EFI_HANDLE         ImageHandle,
  57   IN EFI_SYSTEM_TABLE   *SystemTable
  58   )
  59 {
  60   EFI_STATUS Status;
  61   EFI_EVENT  RootBridgesConnected;
  62
  63   //
  64   // If the platform doesn't support PCI, or PCI enumeration has been disabled,
  65   // install the tables at once, and let the entry point's return code reflect
  66   // the full functionality.
  67   //
  68   if (PcdGetBool (PcdPciDisableBusEnumeration)) {
  69     DEBUG ((DEBUG_INFO, "%a: PCI or its enumeration disabled, installing "
  70       "ACPI tables\n", __FUNCTION__));
  71     return InstallAcpiTables (FindAcpiTableProtocol ());
  72   }
  73
  74   //
  75   // Otherwise, delay installing the ACPI tables until root bridges are
  76   // connected. The entry point's return status will only reflect the callback
  77   // setup. (Note that we're a DXE_DRIVER; our entry point function is invoked
  78   // strictly before BDS is entered and can connect the root bridges.)
  79   //
  80   Status = gBS->CreateEventEx (EVT_NOTIFY_SIGNAL, TPL_CALLBACK,
  81                   OnRootBridgesConnected, NULL /* Context */,
  82                   &gRootBridgesConnectedEventGroupGuid, &RootBridgesConnected);
  83   if (!EFI_ERROR (Status)) {
  84     DEBUG ((DEBUG_INFO,
  85       "%a: waiting for root bridges to be connected, registered callback\n",
  86       __FUNCTION__));
  87   }
  88
  89   return Status;
  90 }