audk/SecurityPkg/Library/TpmCommLib/TisPc.c

178 lines
5.0 KiB
C

/** @file
Basic TIS (TPM Interface Specification) functions.
Copyright (c) 2005 - 2018, Intel Corporation. All rights reserved.<BR>
SPDX-License-Identifier: BSD-2-Clause-Patent
**/
#include "CommonHeader.h"
/**
Check whether TPM chip exist.
@param[in] TisReg Pointer to TIS register.
@retval TRUE TPM chip exists.
@retval FALSE TPM chip is not found.
**/
BOOLEAN
TisPcPresenceCheck (
IN TIS_PC_REGISTERS_PTR TisReg
)
{
UINT8 RegRead;
RegRead = MmioRead8 ((UINTN)&TisReg->Access);
return (BOOLEAN)(RegRead != (UINT8)-1);
}
/**
Check whether the value of a TPM chip register satisfies the input BIT setting.
@param[in] Register Address port of register to be checked.
@param[in] BitSet Check these data bits are set.
@param[in] BitClear Check these data bits are clear.
@param[in] TimeOut The max wait time (unit MicroSecond) when checking register.
@retval EFI_SUCCESS The register satisfies the check bit.
@retval EFI_TIMEOUT The register can't run into the expected status in time.
**/
EFI_STATUS
EFIAPI
TisPcWaitRegisterBits (
IN UINT8 *Register,
IN UINT8 BitSet,
IN UINT8 BitClear,
IN UINT32 TimeOut
)
{
UINT8 RegRead;
UINT32 WaitTime;
for (WaitTime = 0; WaitTime < TimeOut; WaitTime += 30){
RegRead = MmioRead8 ((UINTN)Register);
if ((RegRead & BitSet) == BitSet && (RegRead & BitClear) == 0)
return EFI_SUCCESS;
MicroSecondDelay (30);
}
return EFI_TIMEOUT;
}
/**
Get BurstCount by reading the burstCount field of a TIS register
in the time of default TIS_TIMEOUT_D.
@param[in] TisReg Pointer to TIS register.
@param[out] BurstCount Pointer to a buffer to store the got BurstCount.
@retval EFI_SUCCESS Get BurstCount.
@retval EFI_INVALID_PARAMETER TisReg is NULL or BurstCount is NULL.
@retval EFI_TIMEOUT BurstCount can't be got in time.
**/
EFI_STATUS
EFIAPI
TisPcReadBurstCount (
IN TIS_PC_REGISTERS_PTR TisReg,
OUT UINT16 *BurstCount
)
{
UINT32 WaitTime;
UINT8 DataByte0;
UINT8 DataByte1;
if (BurstCount == NULL || TisReg == NULL) {
return EFI_INVALID_PARAMETER;
}
WaitTime = 0;
do {
//
// TIS_PC_REGISTERS_PTR->burstCount is UINT16, but it is not 2bytes aligned,
// so it needs to use MmioRead8 to read two times
//
DataByte0 = MmioRead8 ((UINTN)&TisReg->BurstCount);
DataByte1 = MmioRead8 ((UINTN)&TisReg->BurstCount + 1);
*BurstCount = (UINT16)((DataByte1 << 8) + DataByte0);
if (*BurstCount != 0) {
return EFI_SUCCESS;
}
MicroSecondDelay (30);
WaitTime += 30;
} while (WaitTime < TIS_TIMEOUT_D);
return EFI_TIMEOUT;
}
/**
Set TPM chip to ready state by sending ready command TIS_PC_STS_READY
to Status Register in time.
@param[in] TisReg Pointer to TIS register.
@retval EFI_SUCCESS TPM chip enters into ready state.
@retval EFI_INVALID_PARAMETER TisReg is NULL.
@retval EFI_TIMEOUT TPM chip can't be set to ready state in time.
**/
EFI_STATUS
EFIAPI
TisPcPrepareCommand (
IN TIS_PC_REGISTERS_PTR TisReg
)
{
EFI_STATUS Status;
if (TisReg == NULL) {
return EFI_INVALID_PARAMETER;
}
MmioWrite8((UINTN)&TisReg->Status, TIS_PC_STS_READY);
Status = TisPcWaitRegisterBits (
&TisReg->Status,
TIS_PC_STS_READY,
0,
TIS_TIMEOUT_B
);
return Status;
}
/**
Get the control of TPM chip by sending requestUse command TIS_PC_ACC_RQUUSE
to ACCESS Register in the time of default TIS_TIMEOUT_A.
@param[in] TisReg Pointer to TIS register.
@retval EFI_SUCCESS Get the control of TPM chip.
@retval EFI_INVALID_PARAMETER TisReg is NULL.
@retval EFI_NOT_FOUND TPM chip doesn't exit.
@retval EFI_TIMEOUT Can't get the TPM control in time.
**/
EFI_STATUS
EFIAPI
TisPcRequestUseTpm (
IN TIS_PC_REGISTERS_PTR TisReg
)
{
EFI_STATUS Status;
if (TisReg == NULL) {
return EFI_INVALID_PARAMETER;
}
if (!TisPcPresenceCheck (TisReg)) {
return EFI_NOT_FOUND;
}
MmioWrite8((UINTN)&TisReg->Access, TIS_PC_ACC_RQUUSE);
//
// No locality set before, ACCESS_X.activeLocality MUST be valid within TIMEOUT_A
//
Status = TisPcWaitRegisterBits (
&TisReg->Access,
(UINT8)(TIS_PC_ACC_ACTIVE |TIS_PC_VALID),
0,
TIS_TIMEOUT_A
);
return Status;
}