Re: [Qemu-arm] Adding /dev/tpm0 to qemu-system-aarch64

[Peter Maydell]

On Mon, 16 Sep 2019 at 17:31, Lakshmi Ramasubramanian
<address@hidden> wrote:
>
> Hello,
>
> I am trying to add a TPM device (/dev/tpm0) for qemu-system-aarch64.
>
> I have a TPM simulator implemented as a Trusted Application (TA). The
> device /dev/tee0 interfaces with the above TA.
>
> Have a TPM driver that interfaces with /dev/tpm0 and talks to /dev/tee0
> in the backend.
>
> Am trying to add /dev/tpm0 through qemu-system-aarch64 command line
> arguments like below:
>
>    -device tpm-tis,tpmdev=tpm0
>
> I see the following error:
>
> qemu-system-aarch64: -device tpm-tis,tpmdev=tpm0: 'tpm-tis' is not a
> valid device model name

This is because QEMU only supports TPM device emulation on x86.
To add it to aarch64 somebody would have to investigate what the
hardware interface for TPM ought to be on aarch64 hardware, and
then implement an emulation of it and add that to the 'virt'
board. (It would probably share a lot of the implementation with
the current x86 TPM, obviously.)

thanks
-- PMM