OvmfPkg/Tcg/Tcg2Config/Tcg2ConfigPeim.c

   1 /** @file
   2   Set TPM device type
   3
   4   In SecurityPkg, this module initializes the TPM device type based on a UEFI
   5   variable and/or hardware detection. In OvmfPkg, the module only performs TPM2
   6   hardware detection.
   7
   8   Copyright (c) 2015, Intel Corporation. All rights reserved.<BR>
   9   Copyright (C) 2018, Red Hat, Inc.
  10
  11   SPDX-License-Identifier: BSD-2-Clause-Patent
  12 **/
  13
  14
  15 #include <PiPei.h>
  16
  17 #include <Guid/TpmInstance.h>
  18 #include <Library/DebugLib.h>
  19 #include <Library/PeiServicesLib.h>
  20 #include <Library/Tpm2DeviceLib.h>
  21 #include <Ppi/TpmInitialized.h>
  22
  23 STATIC CONST EFI_PEI_PPI_DESCRIPTOR mTpmSelectedPpi = {
  24   (EFI_PEI_PPI_DESCRIPTOR_PPI | EFI_PEI_PPI_DESCRIPTOR_TERMINATE_LIST),
  25   &gEfiTpmDeviceSelectedGuid,
  26   NULL
  27 };
  28
  29 STATIC CONST EFI_PEI_PPI_DESCRIPTOR  mTpmInitializationDonePpiList = {
  30   EFI_PEI_PPI_DESCRIPTOR_PPI | EFI_PEI_PPI_DESCRIPTOR_TERMINATE_LIST,
  31   &gPeiTpmInitializationDonePpiGuid,
  32   NULL
  33 };
  34
  35 /**
  36   The entry point for Tcg2 configuration driver.
  37
  38   @param  FileHandle  Handle of the file being invoked.
  39   @param  PeiServices Describes the list of possible PEI Services.
  40 **/
  41 EFI_STATUS
  42 EFIAPI
  43 Tcg2ConfigPeimEntryPoint (
  44   IN       EFI_PEI_FILE_HANDLE  FileHandle,
  45   IN CONST EFI_PEI_SERVICES     **PeiServices
  46   )
  47 {
  48   UINTN                           Size;
  49   EFI_STATUS                      Status;
  50
  51   DEBUG ((DEBUG_INFO, "%a\n", __FUNCTION__));
  52
  53   Status = Tpm2RequestUseTpm ();
  54   if (!EFI_ERROR (Status)) {
  55     DEBUG ((DEBUG_INFO, "%a: TPM2 detected\n", __FUNCTION__));
  56     Size = sizeof (gEfiTpmDeviceInstanceTpm20DtpmGuid);
  57     Status = PcdSetPtrS (
  58                PcdTpmInstanceGuid,
  59                &Size,
  60                &gEfiTpmDeviceInstanceTpm20DtpmGuid
  61                );
  62     ASSERT_EFI_ERROR (Status);
  63   } else {
  64     DEBUG ((DEBUG_INFO, "%a: no TPM2 detected\n", __FUNCTION__));
  65     //
  66     // If no TPM2 was detected, we still need to install
  67     // TpmInitializationDonePpi. Namely, Tcg2Pei will exit early upon seeing
  68     // the default (all-bits-zero) contents of PcdTpmInstanceGuid, thus we have
  69     // to install the PPI in its place, in order to unblock any dependent
  70     // PEIMs.
  71     //
  72     Status = PeiServicesInstallPpi (&mTpmInitializationDonePpiList);
  73     ASSERT_EFI_ERROR (Status);
  74   }
  75
  76   //
  77   // Selection done
  78   //
  79   Status = PeiServicesInstallPpi (&mTpmSelectedPpi);
  80   ASSERT_EFI_ERROR (Status);
  81
  82   return Status;
  83 }