SecurityPkg/Tcg/Tcg2Config/TpmDetection.c

   1 /** @file
   2   TPM1.2/dTPM2.0 auto detection.
   3
   4 Copyright (c) 2015 - 2016, Intel Corporation. All rights reserved.<BR>
   5 This program and the accompanying materials
   6 are licensed and made available under the terms and conditions of the BSD License
   7 which accompanies this distribution.  The full text of the license may be found at
   8 http://opensource.org/licenses/bsd-license.php
   9
  10 THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
  11 WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
  12
  13 **/
  14
  15
  16 #include <PiPei.h>
  17 #include <Ppi/ReadOnlyVariable2.h>
  18
  19 #include <Library/BaseLib.h>
  20 #include <Library/BaseMemoryLib.h>
  21 #include <Library/DebugLib.h>
  22 #include <Library/PeiServicesLib.h>
  23 #include <Library/PcdLib.h>
  24 #include <Library/Tpm12DeviceLib.h>
  25 #include <Library/Tpm12CommandLib.h>
  26 #include <IndustryStandard/Tpm12.h>
  27
  28 #include "Tcg2ConfigNvData.h"
  29
  30 /**
  31   This routine check both SetupVariable and real TPM device, and return final TpmDevice configuration.
  32
  33   @param  SetupTpmDevice  TpmDevice configuration in setup driver
  34
  35   @return TpmDevice configuration
  36 **/
  37 UINT8
  38 DetectTpmDevice (
  39   IN UINT8 SetupTpmDevice
  40   )
  41 {
  42   EFI_STATUS                        Status;
  43   EFI_BOOT_MODE                     BootMode;
  44   TCG2_DEVICE_DETECTION             Tcg2DeviceDetection;
  45   EFI_PEI_READ_ONLY_VARIABLE2_PPI   *VariablePpi;
  46   UINTN                             Size;
  47
  48   Status = PeiServicesGetBootMode (&BootMode);
  49   ASSERT_EFI_ERROR (Status);
  50
  51   //
  52   // In S3, we rely on normal boot Detection, because we save to ReadOnly Variable in normal boot.
  53   //
  54   if (BootMode == BOOT_ON_S3_RESUME) {
  55     DEBUG ((EFI_D_INFO, "DetectTpmDevice: S3 mode\n"));
  56
  57     Status = PeiServicesLocatePpi (&gEfiPeiReadOnlyVariable2PpiGuid, 0, NULL, (VOID **) &VariablePpi);
  58     ASSERT_EFI_ERROR (Status);
  59
  60     Size = sizeof(TCG2_DEVICE_DETECTION);
  61     ZeroMem (&Tcg2DeviceDetection, sizeof(Tcg2DeviceDetection));
  62     Status = VariablePpi->GetVariable (
  63                             VariablePpi,
  64                             TCG2_DEVICE_DETECTION_NAME,
  65                             &gTcg2ConfigFormSetGuid,
  66                             NULL,
  67                             &Size,
  68                             &Tcg2DeviceDetection
  69                             );
  70     if (!EFI_ERROR (Status) &&
  71         (Tcg2DeviceDetection.TpmDeviceDetected >= TPM_DEVICE_MIN) &&
  72         (Tcg2DeviceDetection.TpmDeviceDetected <= TPM_DEVICE_MAX)) {
  73       DEBUG ((EFI_D_ERROR, "TpmDevice from DeviceDetection: %x\n", Tcg2DeviceDetection.TpmDeviceDetected));
  74       return Tcg2DeviceDetection.TpmDeviceDetected;
  75     }
  76   }
  77
  78   DEBUG ((EFI_D_INFO, "DetectTpmDevice:\n"));
  79
  80   // dTPM available and not disabled by setup
  81   // We need check if it is TPM1.2 or TPM2.0
  82   // So try TPM1.2 command at first
  83
  84   Status = Tpm12RequestUseTpm ();
  85   if (EFI_ERROR (Status)) {
  86     //
  87     // dTPM not available
  88     //
  89     return TPM_DEVICE_NULL;
  90   }
  91
  92   if (BootMode == BOOT_ON_S3_RESUME) {
  93     Status = Tpm12Startup (TPM_ST_STATE);
  94   } else {
  95     Status = Tpm12Startup (TPM_ST_CLEAR);
  96   }
  97   if (EFI_ERROR (Status)) {
  98     return TPM_DEVICE_2_0_DTPM;
  99   }
 100
 101   // NO initialization needed again.
 102   Status = PcdSet8S (PcdTpmInitializationPolicy, 0);
 103   ASSERT_EFI_ERROR (Status);
 104   return TPM_DEVICE_1_2;
 105 }