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1 /** @file
2   PTP (Platform TPM Profile) CRB (Command Response Buffer) interface used by dTPM2.0 library.
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 #include <IndustryStandard/Tpm20.h>
16 
17 #include <Library/BaseLib.h>
18 #include <Library/BaseMemoryLib.h>
19 #include <Library/IoLib.h>
20 #include <Library/TimerLib.h>
21 #include <Library/DebugLib.h>
22 #include <Library/Tpm2DeviceLib.h>
23 #include <Library/PcdLib.h>
24 
25 #include <IndustryStandard/TpmPtp.h>
26 #include <IndustryStandard/TpmTis.h>
27 
28 typedef enum {
29   PtpInterfaceTis,
30   PtpInterfaceFifo,
31   PtpInterfaceCrb,
32   PtpInterfaceMax,
33 } PTP_INTERFACE_TYPE;
34 
35 //
36 // Execution of the command may take from several seconds to minutes for certain
37 // commands, such as key generation.
38 //
39 #define PTP_TIMEOUT_MAX             (90000 * 1000)  // 90s
40 
41 //
42 // Max TPM command/reponse length
43 //
44 #define TPMCMDBUFLENGTH             0x500
45 
46 /**
47   Check whether TPM PTP register exist.
48 
49   @param[in] Reg  Pointer to PTP register.
50 
51   @retval    TRUE    TPM PTP exists.
52   @retval    FALSE   TPM PTP is not found.
53 **/
54 BOOLEAN
Tpm2IsPtpPresence(IN VOID * Reg)55 Tpm2IsPtpPresence (
56   IN VOID *Reg
57   )
58 {
59   UINT8                             RegRead;
60 
61   RegRead = MmioRead8 ((UINTN)Reg);
62   if (RegRead == 0xFF) {
63     //
64     // No TPM chip
65     //
66     return FALSE;
67   }
68   return TRUE;
69 }
70 
71 /**
72   Check whether the value of a TPM chip register satisfies the input BIT setting.
73 
74   @param[in]  Register     Address port of register to be checked.
75   @param[in]  BitSet       Check these data bits are set.
76   @param[in]  BitClear     Check these data bits are clear.
77   @param[in]  TimeOut      The max wait time (unit MicroSecond) when checking register.
78 
79   @retval     EFI_SUCCESS  The register satisfies the check bit.
80   @retval     EFI_TIMEOUT  The register can't run into the expected status in time.
81 **/
82 EFI_STATUS
PtpCrbWaitRegisterBits(IN UINT32 * Register,IN UINT32 BitSet,IN UINT32 BitClear,IN UINT32 TimeOut)83 PtpCrbWaitRegisterBits (
84   IN      UINT32                    *Register,
85   IN      UINT32                    BitSet,
86   IN      UINT32                    BitClear,
87   IN      UINT32                    TimeOut
88   )
89 {
90   UINT32                            RegRead;
91   UINT32                            WaitTime;
92 
93   for (WaitTime = 0; WaitTime < TimeOut; WaitTime += 30){
94     RegRead = MmioRead32 ((UINTN)Register);
95     if ((RegRead & BitSet) == BitSet && (RegRead & BitClear) == 0) {
96       return EFI_SUCCESS;
97     }
98     MicroSecondDelay (30);
99   }
100   return EFI_TIMEOUT;
101 }
102 
103 /**
104   Get the control of TPM chip.
105 
106   @param[in] CrbReg                Pointer to CRB register.
107 
108   @retval    EFI_SUCCESS           Get the control of TPM chip.
109   @retval    EFI_INVALID_PARAMETER CrbReg is NULL.
110   @retval    EFI_NOT_FOUND         TPM chip doesn't exit.
111   @retval    EFI_TIMEOUT           Can't get the TPM control in time.
112 **/
113 EFI_STATUS
PtpCrbRequestUseTpm(IN PTP_CRB_REGISTERS_PTR CrbReg)114 PtpCrbRequestUseTpm (
115   IN      PTP_CRB_REGISTERS_PTR      CrbReg
116   )
117 {
118   EFI_STATUS                        Status;
119 
120   if (!Tpm2IsPtpPresence (CrbReg)) {
121     return EFI_NOT_FOUND;
122   }
123 
124   MmioWrite32((UINTN)&CrbReg->LocalityControl, PTP_CRB_LOCALITY_CONTROL_REQUEST_ACCESS);
125   Status = PtpCrbWaitRegisterBits (
126              &CrbReg->LocalityStatus,
127              PTP_CRB_LOCALITY_STATUS_GRANTED,
128              0,
129              PTP_TIMEOUT_A
130              );
131   return Status;
132 }
133 
134 /**
135   Send a command to TPM for execution and return response data.
136 
137   @param[in]      CrbReg        TPM register space base address.
138   @param[in]      BufferIn      Buffer for command data.
139   @param[in]      SizeIn        Size of command data.
140   @param[in, out] BufferOut     Buffer for response data.
141   @param[in, out] SizeOut       Size of response data.
142 
143   @retval EFI_SUCCESS           Operation completed successfully.
144   @retval EFI_BUFFER_TOO_SMALL  Response data buffer is too small.
145   @retval EFI_DEVICE_ERROR      Unexpected device behavior.
146   @retval EFI_UNSUPPORTED       Unsupported TPM version
147 
148 **/
149 EFI_STATUS
PtpCrbTpmCommand(IN PTP_CRB_REGISTERS_PTR CrbReg,IN UINT8 * BufferIn,IN UINT32 SizeIn,IN OUT UINT8 * BufferOut,IN OUT UINT32 * SizeOut)150 PtpCrbTpmCommand (
151   IN     PTP_CRB_REGISTERS_PTR      CrbReg,
152   IN     UINT8                      *BufferIn,
153   IN     UINT32                     SizeIn,
154   IN OUT UINT8                      *BufferOut,
155   IN OUT UINT32                     *SizeOut
156   )
157 {
158   EFI_STATUS                        Status;
159   UINT32                            Index;
160   UINT32                            TpmOutSize;
161   UINT16                            Data16;
162   UINT32                            Data32;
163 
164   DEBUG_CODE (
165     UINTN  DebugSize;
166 
167     DEBUG ((EFI_D_VERBOSE, "PtpCrbTpmCommand Send - "));
168     if (SizeIn > 0x100) {
169       DebugSize = 0x40;
170     } else {
171       DebugSize = SizeIn;
172     }
173     for (Index = 0; Index < DebugSize; Index++) {
174       DEBUG ((EFI_D_VERBOSE, "%02x ", BufferIn[Index]));
175     }
176     if (DebugSize != SizeIn) {
177       DEBUG ((EFI_D_VERBOSE, "...... "));
178       for (Index = SizeIn - 0x20; Index < SizeIn; Index++) {
179         DEBUG ((EFI_D_VERBOSE, "%02x ", BufferIn[Index]));
180       }
181     }
182     DEBUG ((EFI_D_VERBOSE, "\n"));
183   );
184   TpmOutSize = 0;
185 
186   //
187   // STEP 0:
188   // Ready is any time the TPM is ready to receive a command, following a write
189   // of 1 by software to Request.cmdReady, as indicated by the Status field
190   // being cleared to 0.
191   //
192   MmioWrite32((UINTN)&CrbReg->CrbControlRequest, PTP_CRB_CONTROL_AREA_REQUEST_COMMAND_READY);
193   Status = PtpCrbWaitRegisterBits (
194              &CrbReg->CrbControlRequest,
195              0,
196              PTP_CRB_CONTROL_AREA_REQUEST_COMMAND_READY,
197              PTP_TIMEOUT_C
198              );
199   if (EFI_ERROR (Status)) {
200     Status = EFI_DEVICE_ERROR;
201     goto Exit;
202   }
203   Status = PtpCrbWaitRegisterBits (
204              &CrbReg->CrbControlStatus,
205              0,
206              PTP_CRB_CONTROL_AREA_STATUS_TPM_IDLE,
207              PTP_TIMEOUT_C
208              );
209   if (EFI_ERROR (Status)) {
210     Status = EFI_DEVICE_ERROR;
211     goto Exit;
212   }
213 
214   //
215   // STEP 1:
216   // Command Reception occurs following a Ready state between the write of the
217   // first byte of a command to the Command Buffer and the receipt of a write
218   // of 1 to Start.
219   //
220   for (Index = 0; Index < SizeIn; Index++) {
221     MmioWrite8 ((UINTN)&CrbReg->CrbDataBuffer[Index], BufferIn[Index]);
222   }
223   MmioWrite32 ((UINTN)&CrbReg->CrbControlCommandAddressHigh, (UINT32)RShiftU64 ((UINTN)CrbReg->CrbDataBuffer, 32));
224   MmioWrite32 ((UINTN)&CrbReg->CrbControlCommandAddressLow, (UINT32)(UINTN)CrbReg->CrbDataBuffer);
225   MmioWrite32 ((UINTN)&CrbReg->CrbControlCommandSize, sizeof(CrbReg->CrbDataBuffer));
226 
227   MmioWrite64 ((UINTN)&CrbReg->CrbControlResponseAddrss, (UINT32)(UINTN)CrbReg->CrbDataBuffer);
228   MmioWrite32 ((UINTN)&CrbReg->CrbControlResponseSize, sizeof(CrbReg->CrbDataBuffer));
229 
230   //
231   // STEP 2:
232   // Command Execution occurs after receipt of a 1 to Start and the TPM
233   // clearing Start to 0.
234   //
235   MmioWrite32((UINTN)&CrbReg->CrbControlStart, PTP_CRB_CONTROL_START);
236   Status = PtpCrbWaitRegisterBits (
237              &CrbReg->CrbControlStart,
238              0,
239              PTP_CRB_CONTROL_START,
240              PTP_TIMEOUT_MAX
241              );
242   if (EFI_ERROR (Status)) {
243     Status = EFI_DEVICE_ERROR;
244     goto Exit;
245   }
246 
247   //
248   // STEP 3:
249   // Command Completion occurs after completion of a command (indicated by the
250   // TPM clearing TPM_CRB_CTRL_Start_x to 0) and before a write of a 1 by the
251   // software to Request.goIdle.
252   //
253 
254   //
255   // Get response data header
256   //
257   for (Index = 0; Index < sizeof (TPM2_RESPONSE_HEADER); Index++) {
258     BufferOut[Index] = MmioRead8 ((UINTN)&CrbReg->CrbDataBuffer[Index]);
259   }
260   DEBUG_CODE (
261     DEBUG ((EFI_D_VERBOSE, "PtpCrbTpmCommand ReceiveHeader - "));
262     for (Index = 0; Index < sizeof (TPM2_RESPONSE_HEADER); Index++) {
263       DEBUG ((EFI_D_VERBOSE, "%02x ", BufferOut[Index]));
264     }
265     DEBUG ((EFI_D_VERBOSE, "\n"));
266   );
267   //
268   // Check the reponse data header (tag, parasize and returncode)
269   //
270   CopyMem (&Data16, BufferOut, sizeof (UINT16));
271   // TPM2 should not use this RSP_COMMAND
272   if (SwapBytes16 (Data16) == TPM_ST_RSP_COMMAND) {
273     DEBUG ((EFI_D_ERROR, "TPM2: TPM_ST_RSP error - %x\n", TPM_ST_RSP_COMMAND));
274     Status = EFI_UNSUPPORTED;
275     goto Exit;
276   }
277 
278   CopyMem (&Data32, (BufferOut + 2), sizeof (UINT32));
279   TpmOutSize  = SwapBytes32 (Data32);
280   if (*SizeOut < TpmOutSize) {
281     Status = EFI_BUFFER_TOO_SMALL;
282     goto Exit;
283   }
284   *SizeOut = TpmOutSize;
285   //
286   // Continue reading the remaining data
287   //
288   for (Index = sizeof (TPM2_RESPONSE_HEADER); Index < TpmOutSize; Index++) {
289     BufferOut[Index] = MmioRead8 ((UINTN)&CrbReg->CrbDataBuffer[Index]);
290   }
291 Exit:
292   DEBUG_CODE (
293     DEBUG ((EFI_D_VERBOSE, "PtpCrbTpmCommand Receive - "));
294     for (Index = 0; Index < TpmOutSize; Index++) {
295       DEBUG ((EFI_D_VERBOSE, "%02x ", BufferOut[Index]));
296     }
297     DEBUG ((EFI_D_VERBOSE, "\n"));
298   );
299 
300   //
301   // STEP 4:
302   // Idle is any time TPM_CRB_CTRL_STS_x.Status.goIdle is 1.
303   //
304   MmioWrite32((UINTN)&CrbReg->CrbControlRequest, PTP_CRB_CONTROL_AREA_REQUEST_GO_IDLE);
305   return Status;
306 }
307 
308 /**
309   Send a command to TPM for execution and return response data.
310 
311   @param[in]      TisReg        TPM register space base address.
312   @param[in]      BufferIn      Buffer for command data.
313   @param[in]      SizeIn        Size of command data.
314   @param[in, out] BufferOut     Buffer for response data.
315   @param[in, out] SizeOut       Size of response data.
316 
317   @retval EFI_SUCCESS           Operation completed successfully.
318   @retval EFI_BUFFER_TOO_SMALL  Response data buffer is too small.
319   @retval EFI_DEVICE_ERROR      Unexpected device behavior.
320   @retval EFI_UNSUPPORTED       Unsupported TPM version
321 
322 **/
323 EFI_STATUS
324 Tpm2TisTpmCommand (
325   IN     TIS_PC_REGISTERS_PTR       TisReg,
326   IN     UINT8                      *BufferIn,
327   IN     UINT32                     SizeIn,
328   IN OUT UINT8                      *BufferOut,
329   IN OUT UINT32                     *SizeOut
330   );
331 
332 /**
333   Get the control of TPM chip by sending requestUse command TIS_PC_ACC_RQUUSE
334   to ACCESS Register in the time of default TIS_TIMEOUT_A.
335 
336   @param[in] TisReg                Pointer to TIS register.
337 
338   @retval    EFI_SUCCESS           Get the control of TPM chip.
339   @retval    EFI_INVALID_PARAMETER TisReg is NULL.
340   @retval    EFI_NOT_FOUND         TPM chip doesn't exit.
341   @retval    EFI_TIMEOUT           Can't get the TPM control in time.
342 **/
343 EFI_STATUS
344 TisPcRequestUseTpm (
345   IN     TIS_PC_REGISTERS_PTR       TisReg
346   );
347 
348 /**
349   Return PTP interface type.
350 
351   @param[in] Register                Pointer to PTP register.
352 
353   @return PTP interface type.
354 **/
355 PTP_INTERFACE_TYPE
Tpm2GetPtpInterface(IN VOID * Register)356 Tpm2GetPtpInterface (
357   IN VOID *Register
358   )
359 {
360   PTP_CRB_INTERFACE_IDENTIFIER  InterfaceId;
361   PTP_FIFO_INTERFACE_CAPABILITY InterfaceCapability;
362 
363   if (!Tpm2IsPtpPresence (Register)) {
364     return PtpInterfaceMax;
365   }
366   //
367   // Check interface id
368   //
369   InterfaceId.Uint32 = MmioRead32 ((UINTN)&((PTP_CRB_REGISTERS *)Register)->InterfaceId);
370   InterfaceCapability.Uint32 = MmioRead32 ((UINTN)&((PTP_FIFO_REGISTERS *)Register)->InterfaceCapability);
371 
372   if ((InterfaceId.Bits.InterfaceType == PTP_INTERFACE_IDENTIFIER_INTERFACE_TYPE_CRB) &&
373       (InterfaceId.Bits.InterfaceVersion == PTP_INTERFACE_IDENTIFIER_INTERFACE_VERSION_CRB) &&
374       (InterfaceId.Bits.CapCRB != 0)) {
375     return PtpInterfaceCrb;
376   }
377   if ((InterfaceId.Bits.InterfaceType == PTP_INTERFACE_IDENTIFIER_INTERFACE_TYPE_FIFO) &&
378       (InterfaceId.Bits.InterfaceVersion == PTP_INTERFACE_IDENTIFIER_INTERFACE_VERSION_FIFO) &&
379       (InterfaceId.Bits.CapFIFO != 0) &&
380       (InterfaceCapability.Bits.InterfaceVersion == INTERFACE_CAPABILITY_INTERFACE_VERSION_PTP)) {
381     return PtpInterfaceFifo;
382   }
383   return PtpInterfaceTis;
384 }
385 
386 /**
387   Dump PTP register information.
388 
389   @param[in] Register                Pointer to PTP register.
390 **/
391 VOID
DumpPtpInfo(IN VOID * Register)392 DumpPtpInfo (
393   IN VOID *Register
394   )
395 {
396   PTP_CRB_INTERFACE_IDENTIFIER  InterfaceId;
397   PTP_FIFO_INTERFACE_CAPABILITY InterfaceCapability;
398   UINT8                         StatusEx;
399   UINT16                        Vid;
400   UINT16                        Did;
401   UINT8                         Rid;
402   PTP_INTERFACE_TYPE            PtpInterface;
403 
404   if (!Tpm2IsPtpPresence (Register)) {
405     return ;
406   }
407 
408   InterfaceId.Uint32 = MmioRead32 ((UINTN)&((PTP_CRB_REGISTERS *)Register)->InterfaceId);
409   InterfaceCapability.Uint32 = MmioRead32 ((UINTN)&((PTP_FIFO_REGISTERS *)Register)->InterfaceCapability);
410   StatusEx = MmioRead8 ((UINTN)&((PTP_FIFO_REGISTERS *)Register)->StatusEx);
411 
412   //
413   // Dump InterfaceId Register for PTP
414   //
415   DEBUG ((EFI_D_INFO, "InterfaceId - 0x%08x\n", InterfaceId.Uint32));
416   DEBUG ((EFI_D_INFO, "  InterfaceType    - 0x%02x\n", InterfaceId.Bits.InterfaceType));
417   if (InterfaceId.Bits.InterfaceType != PTP_INTERFACE_IDENTIFIER_INTERFACE_TYPE_TIS) {
418     DEBUG ((EFI_D_INFO, "  InterfaceVersion - 0x%02x\n", InterfaceId.Bits.InterfaceVersion));
419     DEBUG ((EFI_D_INFO, "  CapFIFO          - 0x%x\n", InterfaceId.Bits.CapFIFO));
420     DEBUG ((EFI_D_INFO, "  CapCRB           - 0x%x\n", InterfaceId.Bits.CapCRB));
421   }
422 
423   //
424   // Dump Capability Register for TIS and FIFO
425   //
426   DEBUG ((EFI_D_INFO, "InterfaceCapability - 0x%08x\n", InterfaceCapability.Uint32));
427   if ((InterfaceId.Bits.InterfaceType == PTP_INTERFACE_IDENTIFIER_INTERFACE_TYPE_TIS) ||
428       (InterfaceId.Bits.InterfaceType == PTP_INTERFACE_IDENTIFIER_INTERFACE_TYPE_FIFO)) {
429     DEBUG ((EFI_D_INFO, "  InterfaceVersion - 0x%x\n", InterfaceCapability.Bits.InterfaceVersion));
430   }
431 
432   //
433   // Dump StatusEx Register for PTP FIFO
434   //
435   DEBUG ((EFI_D_INFO, "StatusEx - 0x%02x\n", StatusEx));
436   if (InterfaceCapability.Bits.InterfaceVersion == INTERFACE_CAPABILITY_INTERFACE_VERSION_PTP) {
437     DEBUG ((EFI_D_INFO, "  TpmFamily - 0x%x\n", (StatusEx & PTP_FIFO_STS_EX_TPM_FAMILY) >> PTP_FIFO_STS_EX_TPM_FAMILY_OFFSET));
438   }
439 
440   Vid = 0xFFFF;
441   Did = 0xFFFF;
442   Rid = 0xFF;
443   PtpInterface = Tpm2GetPtpInterface (Register);
444   DEBUG ((EFI_D_INFO, "PtpInterface - %x\n", PtpInterface));
445   switch (PtpInterface) {
446   case PtpInterfaceCrb:
447     Vid = MmioRead16 ((UINTN)&((PTP_CRB_REGISTERS *)Register)->Vid);
448     Did = MmioRead16 ((UINTN)&((PTP_CRB_REGISTERS *)Register)->Did);
449     Rid = (UINT8)InterfaceId.Bits.Rid;
450     break;
451   case PtpInterfaceFifo:
452   case PtpInterfaceTis:
453     Vid = MmioRead16 ((UINTN)&((PTP_FIFO_REGISTERS *)Register)->Vid);
454     Did = MmioRead16 ((UINTN)&((PTP_FIFO_REGISTERS *)Register)->Did);
455     Rid = MmioRead8 ((UINTN)&((PTP_FIFO_REGISTERS *)Register)->Rid);
456     break;
457   default:
458     break;
459   }
460   DEBUG ((EFI_D_INFO, "VID - 0x%04x\n", Vid));
461   DEBUG ((EFI_D_INFO, "DID - 0x%04x\n", Did));
462   DEBUG ((EFI_D_INFO, "RID - 0x%02x\n", Rid));
463 }
464 
465 /**
466   This service enables the sending of commands to the TPM2.
467 
468   @param[in]      InputParameterBlockSize  Size of the TPM2 input parameter block.
469   @param[in]      InputParameterBlock      Pointer to the TPM2 input parameter block.
470   @param[in,out]  OutputParameterBlockSize Size of the TPM2 output parameter block.
471   @param[in]      OutputParameterBlock     Pointer to the TPM2 output parameter block.
472 
473   @retval EFI_SUCCESS            The command byte stream was successfully sent to the device and a response was successfully received.
474   @retval EFI_DEVICE_ERROR       The command was not successfully sent to the device or a response was not successfully received from the device.
475   @retval EFI_BUFFER_TOO_SMALL   The output parameter block is too small.
476 **/
477 EFI_STATUS
478 EFIAPI
DTpm2SubmitCommand(IN UINT32 InputParameterBlockSize,IN UINT8 * InputParameterBlock,IN OUT UINT32 * OutputParameterBlockSize,IN UINT8 * OutputParameterBlock)479 DTpm2SubmitCommand (
480   IN UINT32            InputParameterBlockSize,
481   IN UINT8             *InputParameterBlock,
482   IN OUT UINT32        *OutputParameterBlockSize,
483   IN UINT8             *OutputParameterBlock
484   )
485 {
486   PTP_INTERFACE_TYPE  PtpInterface;
487 
488   PtpInterface = Tpm2GetPtpInterface ((VOID *) (UINTN) PcdGet64 (PcdTpmBaseAddress));
489   switch (PtpInterface) {
490   case PtpInterfaceCrb:
491     return PtpCrbTpmCommand (
492            (PTP_CRB_REGISTERS_PTR) (UINTN) PcdGet64 (PcdTpmBaseAddress),
493            InputParameterBlock,
494            InputParameterBlockSize,
495            OutputParameterBlock,
496            OutputParameterBlockSize
497            );
498   case PtpInterfaceFifo:
499   case PtpInterfaceTis:
500     return Tpm2TisTpmCommand (
501            (TIS_PC_REGISTERS_PTR) (UINTN) PcdGet64 (PcdTpmBaseAddress),
502            InputParameterBlock,
503            InputParameterBlockSize,
504            OutputParameterBlock,
505            OutputParameterBlockSize
506            );
507   default:
508     return EFI_NOT_FOUND;
509   }
510 }
511 
512 /**
513   This service requests use TPM2.
514 
515   @retval EFI_SUCCESS      Get the control of TPM2 chip.
516   @retval EFI_NOT_FOUND    TPM2 not found.
517   @retval EFI_DEVICE_ERROR Unexpected device behavior.
518 **/
519 EFI_STATUS
520 EFIAPI
DTpm2RequestUseTpm(VOID)521 DTpm2RequestUseTpm (
522   VOID
523   )
524 {
525   PTP_INTERFACE_TYPE  PtpInterface;
526 
527   PtpInterface = Tpm2GetPtpInterface ((VOID *) (UINTN) PcdGet64 (PcdTpmBaseAddress));
528   switch (PtpInterface) {
529   case PtpInterfaceCrb:
530     return PtpCrbRequestUseTpm ((PTP_CRB_REGISTERS_PTR) (UINTN) PcdGet64 (PcdTpmBaseAddress));
531   case PtpInterfaceFifo:
532   case PtpInterfaceTis:
533     return TisPcRequestUseTpm ((TIS_PC_REGISTERS_PTR) (UINTN) PcdGet64 (PcdTpmBaseAddress));
534   default:
535     return EFI_NOT_FOUND;
536   }
537 }
538