[PATCH v4] SecurityPkg: Add retry mechanism for tpm command


Qi Zhang
 

REF: https://bugzilla.tianocore.org/show_bug.cgi?id=3D3980

As per TCG PC Client Device Driver Design Principle document,
if tpm commands fails due to timeout condition, then it should
have retry mechanism (3 retry attempts).
Existing implementation of PtpCrbTpmCommand does not have retry
mechanism if it fails with EFI_TIMEOUT.

See TCG PC Client Device Driver Design Principles for TPM 2.0
https://trustedcomputinggroup.org/wp-content/uploads/TCG_PCClient_Device_Dr=
iver_Design_Principles_TPM2p0_v1p1_r4_211104_final.pdf
Vision 1.1, Revision 0.04
Section 7.2.1

Signed-off-by: Qi Zhang <qi1.zhang@...>
Cc: Jiewen Yao <jiewen.yao@...>
Cc: Jian J Wang <jian.j.wang@...>
Reviewed-by: Jiewen Yao <jiewen.yao@...>
Tested-by: Swapnil Patil <S.Keshavrao.Patil@...>
---
.../Library/Tpm2DeviceLibDTpm/Tpm2Ptp.c | 108 +++++++++++-------
1 file changed, 69 insertions(+), 39 deletions(-)

diff --git a/SecurityPkg/Library/Tpm2DeviceLibDTpm/Tpm2Ptp.c b/SecurityPkg/=
Library/Tpm2DeviceLibDTpm/Tpm2Ptp.c
index 1d99beaa10..840265292a 100644
--- a/SecurityPkg/Library/Tpm2DeviceLibDTpm/Tpm2Ptp.c
+++ b/SecurityPkg/Library/Tpm2DeviceLibDTpm/Tpm2Ptp.c
@@ -33,6 +33,12 @@ SPDX-License-Identifier: BSD-2-Clause-Patent
//=0D
#define TPMCMDBUFLENGTH 0x500=0D
=0D
+//=0D
+// Max retry count according to Spec TCG PC Client Device Driver Design Pr=
inciples=0D
+// for TPM2.0, Version 1.1, Revision 0.04, Section 7.2.1=0D
+//=0D
+#define RETRY_CNT_MAX 3=0D
+=0D
/**=0D
Check whether TPM PTP register exist.=0D
=0D
@@ -153,6 +159,7 @@ PtpCrbTpmCommand (
UINT32 TpmOutSize;=0D
UINT16 Data16;=0D
UINT32 Data32;=0D
+ UINT8 RetryCnt;=0D
=0D
DEBUG_CODE_BEGIN ();=0D
UINTN DebugSize;=0D
@@ -179,53 +186,76 @@ PtpCrbTpmCommand (
DEBUG_CODE_END ();=0D
TpmOutSize =3D 0;=0D
=0D
- //=0D
- // STEP 0:=0D
- // if CapCRbIdelByPass =3D=3D 0, enforce Idle state before sending comma=
nd=0D
- //=0D
- if ((GetCachedIdleByPass () =3D=3D 0) && ((MmioRead32 ((UINTN)&CrbReg->C=
rbControlStatus) & PTP_CRB_CONTROL_AREA_STATUS_TPM_IDLE) =3D=3D 0)) {=0D
+ RetryCnt =3D 0;=0D
+ while (TRUE) {=0D
+ //=0D
+ // STEP 0:=0D
+ // if CapCRbIdelByPass =3D=3D 0, enforce Idle state before sending com=
mand=0D
+ //=0D
+ if ((GetCachedIdleByPass () =3D=3D 0) && ((MmioRead32 ((UINTN)&CrbReg-=
CrbControlStatus) & PTP_CRB_CONTROL_AREA_STATUS_TPM_IDLE) =3D=3D 0)) {=0D
+ Status =3D PtpCrbWaitRegisterBits (=0D
+ &CrbReg->CrbControlStatus,=0D
+ PTP_CRB_CONTROL_AREA_STATUS_TPM_IDLE,=0D
+ 0,=0D
+ PTP_TIMEOUT_C=0D
+ );=0D
+ if (EFI_ERROR (Status)) {=0D
+ RetryCnt++;=0D
+ if (RetryCnt < RETRY_CNT_MAX) {=0D
+ MmioWrite32 ((UINTN)&CrbReg->CrbControlRequest, PTP_CRB_CONTROL_=
AREA_REQUEST_GO_IDLE);=0D
+ continue;=0D
+ } else {=0D
+ //=0D
+ // Try to goIdle to recover TPM=0D
+ //=0D
+ Status =3D EFI_DEVICE_ERROR;=0D
+ goto GoIdle_Exit;=0D
+ }=0D
+ }=0D
+ }=0D
+=0D
+ //=0D
+ // STEP 1:=0D
+ // Ready is any time the TPM is ready to receive a command, following =
a write=0D
+ // of 1 by software to Request.cmdReady, as indicated by the Status fi=
eld=0D
+ // being cleared to 0.=0D
+ //=0D
+ MmioWrite32 ((UINTN)&CrbReg->CrbControlRequest, PTP_CRB_CONTROL_AREA_R=
EQUEST_COMMAND_READY);=0D
Status =3D PtpCrbWaitRegisterBits (=0D
- &CrbReg->CrbControlStatus,=0D
- PTP_CRB_CONTROL_AREA_STATUS_TPM_IDLE,=0D
+ &CrbReg->CrbControlRequest,=0D
0,=0D
+ PTP_CRB_CONTROL_AREA_REQUEST_COMMAND_READY,=0D
PTP_TIMEOUT_C=0D
);=0D
if (EFI_ERROR (Status)) {=0D
- //=0D
- // Try to goIdle to recover TPM=0D
- //=0D
- Status =3D EFI_DEVICE_ERROR;=0D
- goto GoIdle_Exit;=0D
+ RetryCnt++;=0D
+ if (RetryCnt < RETRY_CNT_MAX) {=0D
+ MmioWrite32 ((UINTN)&CrbReg->CrbControlRequest, PTP_CRB_CONTROL_AR=
EA_REQUEST_GO_IDLE);=0D
+ continue;=0D
+ } else {=0D
+ Status =3D EFI_DEVICE_ERROR;=0D
+ goto GoIdle_Exit;=0D
+ }=0D
}=0D
- }=0D
=0D
- //=0D
- // STEP 1:=0D
- // Ready is any time the TPM is ready to receive a command, following a =
write=0D
- // of 1 by software to Request.cmdReady, as indicated by the Status fiel=
d=0D
- // being cleared to 0.=0D
- //=0D
- MmioWrite32 ((UINTN)&CrbReg->CrbControlRequest, PTP_CRB_CONTROL_AREA_REQ=
UEST_COMMAND_READY);=0D
- Status =3D PtpCrbWaitRegisterBits (=0D
- &CrbReg->CrbControlRequest,=0D
- 0,=0D
- PTP_CRB_CONTROL_AREA_REQUEST_COMMAND_READY,=0D
- PTP_TIMEOUT_C=0D
- );=0D
- if (EFI_ERROR (Status)) {=0D
- Status =3D EFI_DEVICE_ERROR;=0D
- goto GoIdle_Exit;=0D
- }=0D
+ Status =3D PtpCrbWaitRegisterBits (=0D
+ &CrbReg->CrbControlStatus,=0D
+ 0,=0D
+ PTP_CRB_CONTROL_AREA_STATUS_TPM_IDLE,=0D
+ PTP_TIMEOUT_C=0D
+ );=0D
+ if (EFI_ERROR (Status)) {=0D
+ RetryCnt++;=0D
+ if (RetryCnt < RETRY_CNT_MAX) {=0D
+ MmioWrite32 ((UINTN)&CrbReg->CrbControlRequest, PTP_CRB_CONTROL_AR=
EA_REQUEST_GO_IDLE);=0D
+ continue;=0D
+ } else {=0D
+ Status =3D EFI_DEVICE_ERROR;=0D
+ goto GoIdle_Exit;=0D
+ }=0D
+ }=0D
=0D
- Status =3D PtpCrbWaitRegisterBits (=0D
- &CrbReg->CrbControlStatus,=0D
- 0,=0D
- PTP_CRB_CONTROL_AREA_STATUS_TPM_IDLE,=0D
- PTP_TIMEOUT_C=0D
- );=0D
- if (EFI_ERROR (Status)) {=0D
- Status =3D EFI_DEVICE_ERROR;=0D
- goto GoIdle_Exit;=0D
+ break;=0D
}=0D
=0D
//=0D
--=20
2.26.2.windows.1

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