[PATCH] doc: qemu: switch swtpm instruction to 'tpm autostart'

[Ilias Apalodimas]

Hi Heinrich,

On Fri, 8 Sept 2023 at 22:16, Heinrich Schuchardt <xypron.glpk at gmx.de> wrote:
>
>
>
> On 6/16/23 10:42, Ilias Apalodimas wrote:
> > We don't have a documentation page for our TPM subsystem.  I plan
> > on sending one in the future,  but in the meantime document the
> > new 'tpm autostart' command in the QEMU instructions while using
> > a SWTPM
> >
> > Signed-off-by: Ilias Apalodimas <ilias.apalodimas at linaro.org>
> > Reviewed-by: Simon Glass <sjg at chromium.org>
> > ---
> >   doc/board/emulation/qemu-arm.rst | 2 +-
> >   1 file changed, 1 insertion(+), 1 deletion(-)
> >
> > diff --git a/doc/board/emulation/qemu-arm.rst b/doc/board/emulation/qemu-arm.rst
> > index 16f66388eb1f..30819637723d 100644
> > --- a/doc/board/emulation/qemu-arm.rst
> > +++ b/doc/board/emulation/qemu-arm.rst
> > @@ -113,7 +113,7 @@ In a second console invoke qemu-system-aarch64 with::
> >
> >   Enable the TPM on U-Boot's command line with::
> >
> > -    tpm2 startup TPM2_SU_CLEAR
> > +    tpm autostart
>
> Do you really intend switch from TPM v2 to the deprecated TPM v1?
>
> I assume you mean "tpm2 autostart".

Both tpm v1/v2 commands will call do_tpm(). That function will
properly call a v1 or v2 API depending on the device it discovered. So
the autostart function will work for both variants correctly.

P.S: Looking at commit e663b2ff4ba2("tpm: Add 'tpm autostart' shell
command"), I apparently messed up a c/p and autostart is missing from
the v1 version of the command.  I'll send a patch to fix that

Thanks
/Ilias

>
> Best regards
>
> Heinrich
>
> >
> >   Debug UART
> >   ----------