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> // gRootBridgesConnectedEve...
  11 #include <Library/DebugLib.h>                    // DEBUG()
  12 #include <Library/PcdLib.h>                      // PcdGetBool()
  13 #include <Library/UefiBootServicesTableLib.h>    // gBS
  14 #include <Protocol/AcpiTable.h>                  // EFI_ACPI_TABLE_PROTOCOL
  15
  16 #include "AcpiPlatform.h"
  17
  18 STATIC
  19 EFI_ACPI_TABLE_PROTOCOL *
  20 FindAcpiTableProtocol (
  21   VOID
  22   )
  23 {
  24   EFI_STATUS               Status;
  25   EFI_ACPI_TABLE_PROTOCOL  *AcpiTable;
  26
  27   Status = gBS->LocateProtocol (
  28                   &gEfiAcpiTableProtocolGuid,
  29                   NULL,
  30                   (VOID **)&AcpiTable
  31                   );
  32   ASSERT_EFI_ERROR (Status);
  33   return AcpiTable;
  34 }
  35
  36 STATIC
  37 VOID
  38 EFIAPI
  39 OnRootBridgesConnected (
  40   IN EFI_EVENT  Event,
  41   IN VOID       *Context
  42   )
  43 {
  44   EFI_STATUS  Status;
  45
  46   DEBUG ((
  47     DEBUG_INFO,
  48     "%a: root bridges have been connected, installing ACPI tables\n",
  49     __FUNCTION__
  50     ));
  51   Status = InstallAcpiTables (FindAcpiTableProtocol ());
  52   if (EFI_ERROR (Status)) {
  53     DEBUG ((DEBUG_ERROR, "%a: InstallAcpiTables: %r\n", __FUNCTION__, Status));
  54   }
  55
  56   gBS->CloseEvent (Event);
  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 ((
  76       DEBUG_INFO,
  77       "%a: PCI or its enumeration disabled, installing "
  78       "ACPI tables\n",
  79       __FUNCTION__
  80       ));
  81     return InstallAcpiTables (FindAcpiTableProtocol ());
  82   }
  83
  84   //
  85   // Otherwise, delay installing the ACPI tables until root bridges are
  86   // connected. The entry point's return status will only reflect the callback
  87   // setup. (Note that we're a DXE_DRIVER; our entry point function is invoked
  88   // strictly before BDS is entered and can connect the root bridges.)
  89   //
  90   Status = gBS->CreateEventEx (
  91                   EVT_NOTIFY_SIGNAL,
  92                   TPL_CALLBACK,
  93                   OnRootBridgesConnected,
  94                   NULL /* Context */,
  95                   &gRootBridgesConnectedEventGroupGuid,
  96                   &RootBridgesConnected
  97                   );
  98   if (!EFI_ERROR (Status)) {
  99     DEBUG ((
 100       DEBUG_INFO,
 101       "%a: waiting for root bridges to be connected, registered callback\n",
 102       __FUNCTION__
 103       ));
 104   }
 105
 106   return Status;
 107 }