Re: [edk2-devel] [PATCH v2 0/3] Ovmf: enable TPM 1.2

["Stefan Berger" <stefanb@linux.ibm.com>]

On 2/15/20 6:33 AM, Marc-André Lureau wrote:
> Hi Yao
>
> On Thu, Feb 13, 2020 at 2:51 PM Yao, Jiewen <jiewen.yao@intel.com> wrote:
>> Hi Lureau
>> I don’t think we should expose the TPM Interface type via TpmCommandLib.
>>
>> That is the TPM device implementation. The TPM device might use TIS/FIFO/CRB, but there might be also other type such as I2C, or fTPM implementation type.
>>
>> To distinguish TPM2.0 or TPM1.2, the standard way is to send startup command.
> Thanks for the feedback, unfortunately I don't know how to achieve
> this for both tpm/vtpm (uninitialized) & passthrough (initialized).
>
> If the device is uninitialized, sending Tpm12Startup (TPM_ST_CLEAR) to
> detect 1.2 in Tcg2ConfigPeimEntryPoint will work, but then
> Tpm12Startup () in TcgPei:PeimEntryMA will later fail.
>
> If the device is initialized/passthrough, sending Tpm12Startup
> (TPM_ST_CLEAR) will fail, so it could send Tpm12Startup (TPM_ST_STATE)
> instead. But that will fail to detect uninitialized 1.2 device.
>
> I am stuck, any help welcome!

You should be able to do this in the same way as we do it in QEMU:

https://github.com/qemu/qemu/blob/master/hw/tpm/tpm_util.c#L190

Send a command (non-TPM_Startup) to it and inspect the TAG in the header.


    Stefan


>
> thanks
>
>> Thank you
>> Yao Jiewen
>>
>>
>>> -----Original Message-----
>>> From: devel@edk2.groups.io <devel@edk2.groups.io> On Behalf Of
>>> marcandre.lureau@redhat.com
>>> Sent: Thursday, February 13, 2020 9:12 PM
>>> To: edk2-devel@lists.01.org; devel@edk2.groups.io
>>> Cc: stefanb@linux.ibm.com; lersek@redhat.com; simon.hardy@itdev.co.uk;
>>> Marc-André Lureau <marcandre.lureau@redhat.com>
>>> Subject: [edk2-devel] [PATCH v2 0/3] Ovmf: enable TPM 1.2
>>>
>>> From: Marc-André Lureau <marcandre.lureau@redhat.com>
>>>
>>> Hi,
>>>
>>> The following patches add basic TPM 1.2 support for Ovmf/QEMU.
>>>
>>> I tested successfully Win10 with TIS/TPM 1.2 & CRB/TPM 2.0
>>> passthrough, and emulated CRB/TPM 2.0.
>>> (fwiw, I haven't tried to enable TPM_CONFIG_ENABLE)
>>>
>>> Marc-André Lureau (3):
>>>    Ovmf: rename TPM2 config prefix to TPM
>>>    SecurityPkg: export Tpm12GetPtpInterfaceType()
>>>    Ovmf: enable TPM 1.2 support
>>>
>>>   OvmfPkg/OvmfPkgIa32.dsc                       | 39 +++++++++++++------
>>>   OvmfPkg/OvmfPkgIa32.fdf                       | 10 +++--
>>>   OvmfPkg/OvmfPkgIa32X64.dsc                    | 39 +++++++++++++------
>>>   OvmfPkg/OvmfPkgIa32X64.fdf                    | 10 +++--
>>>   OvmfPkg/OvmfPkgX64.dsc                        | 39 +++++++++++++------
>>>   OvmfPkg/OvmfPkgX64.fdf                        | 10 +++--
>>>   OvmfPkg/Tcg/Tcg2Config/Tcg2ConfigPei.inf      |  3 ++
>>>   OvmfPkg/Tcg/Tcg2Config/Tcg2ConfigPeim.c       | 17 +++++++-
>>>   SecurityPkg/Include/Library/Tpm12DeviceLib.h  | 13 +++++++
>>>   .../Library/Tpm12DeviceLibDTpm/Tpm12Tis.c     | 17 ++++----
>>>   10 files changed, 141 insertions(+), 56 deletions(-)
>>>
>>> --
>>> 2.25.0.rc2.1.g09a9a1a997
>>>
>>>
>>>
>>
>>
>>
>
> 
>