Re: [PATCH v4 1/5] acpi: Convert build_tpm2() to build_append* API

[Stefan Berger]

On 6/19/20 5:43 AM, Auger Eric wrote:
> Hi Laszlo,
>
> On 6/19/20 11:38 AM, Laszlo Ersek wrote:
> > On 06/18/20 09:50, Auger Eric wrote:
> > > Hi Stefan, Igor,
> > >
> > > On 6/16/20 4:11 PM, Stefan Berger wrote:
> > > > On 6/16/20 8:33 AM, Igor Mammedov wrote:
> > > > > nevertheless looks like faithfull conversion,
> > > > > btw why you didn't drop Acpi20TPM2 structure definition?
> > > > If we get rid of the table we should keep a reference to this document,
> > > > table 7: "TCG ACPI Specification; Family 1.2 and 2.0; Level 00 Revision
> > > > 00.37, December 19, 2014"
> > > >
> > > > https://trustedcomputinggroup.org/wp-content/uploads/TCG_ACPIGeneralSpecification_1-10_0-37-Published.pdf
> > > Further looking at this spec, the log_area_minimum_length and
> > > log_area_start_address only are described in
> > > - Table 2 (TCG Hardware InterfaceDescription Table Format for TPM 1.2
> > > Clients)
> > > - Table 4 (TCG Hardware Interface Description Table Format for TPM 1.2
> > > Servers)
> > > but not in Table 7, ie. not for TPM 2.0.
> > >
> > > Are they really needed for TPM2 or what do I miss?
> > (side comment:
> >
> > LASA and LAML are optional with TPM-2.0. From the discussion at
> > <https://bugzilla.tianocore.org/show_bug.cgi?id=978>.


They are needed for (x86) BIOS, such as SeaBIOS, not for UEFI, though. I 
do not know about ARM.


> Thank you for the pointer and info. I failed to find this info in the
> spec. Given the risk of confusion, I would personally keep struct
> Acpi20TPM2 and maybe add a comment. Stefan?

Either way is fine with me for as long as we know where to find the 
layout of the structure.

  Stefan

> Thanks
>
> Eric
> > )
> >
> > Thanks
> > Laszlo