Re: [PATCH v7 0/3] Add support for TPM devices over I2C bus

[Stefan Berger]

On 3/27/23 07:18, Joel Stanley wrote:
> On Mon, 27 Mar 2023 at 11:11, Stefan Berger <stefanb@linux.ibm.com> wrote:
> > On 3/26/23 21:05, Joel Stanley wrote:
> > > Hi Ninad,
> > >
> > > On Sun, 26 Mar 2023 at 22:44, Ninad Palsule <ninad@linux.ibm.com> wrote:
> > > > Hello,
> > > >
> > > > I have incorporated review comments from Stefan. Please review.
> > > >
> > > > This drop adds support for the TPM devices attached to the I2C bus. It
> > > > only supports the TPM2 protocol. You need to run it with the external
> > > > TPM emulator like swtpm. I have tested it with swtpm.
> > >
> > > Nice work. I tested these stop cedric's aspeed-8.0 qemu tree, using
> > > the rainier machine and the openbmc dev-6.1 kernel.
> > >
> > > We get this message when booting from a kernel:
> > >
> > > [    0.582699] tpm_tis_i2c 12-002e: 2.0 TPM (device-id 0x1, rev-id 1)
> > > [    0.586361] tpm tpm0: A TPM error (256) occurred attempting the self test
> > > [    0.586623] tpm tpm0: starting up the TPM manually
> > >
> > > Do we understand why the error appears?
> >
> > The firmware did not initialize the TPM 2.
>
> Which firmware are we talking about here?

This happens if either no firmware is used or the firmware doesn't know how to 
talk to the TPM 2.
Linux detects that the TPM 2 wasn't initialized (TPM2_Startup was not sent).
  
   Stefan