[U-Boot] tpm TIS TPMv2.0

[Miquel Raynal <miquel.raynal@bootlin.com>]

Hi Martin,

> > > > > Is there any specific reason why the new tpm2_tis_spi_xfer doesn't  
> > > > support full duplex? It seems we did some work in parallel but you
> > > > sent the patches earlier. Is that codes tested against an existing
> > > > TPM v2? I have a working implementation what runs on SLB9670 including  
> > full duplex.  
> > > >
> > > > What do you mean exactly?
> > > >
> > > > I don't think the TPM2 protocol makes real use of full-duplex unless
> > > > for the wait state between the host command and the actual xfer.  
> > >
> > > You are right, TIS 1.3 FIFO doesn’t use full duplex in physical level. What I  
> > mean is that the driver you just wrote doesn't use the xfer function in that
> > way that you can specify in and out parameters at same time. I did this in my
> > implementation what gave me an easy chance to control the CS# of the TPM.
> > 
> > Do you need this CS# handling for more advanced features? Same question
> > for the in/out xfers?
> >   
> > > Can you tell me on what TPM did you test? For the SLB9670 the code
> > > doesn't work on my hardware.  
> > 
> > I tested with a ST33TPHF20 SPI TPM.
> > 
> > I'm surprised it did not work with an SLB9670, I don't see anything in the spec
> > explaining this CS# specificity.  
> 
> The CS# may controls an internal state machine and the SLB9670 uses that signal. 
> >   
> > > For the code you wrote I'm considering to add a few lines to control
> > > the CS# in that way how my xfer is doing this for the SLB9670.  
> > 
> > Yes please, share the patch and add me in cc so I could test it with mine.  
> Fine, will do so soon.

What's the status of this? I did not spot any patches, maybe you
forgot to copy me? Otherwise do you still plan to share the changes?
That would be great!

Thanks,
Miquèl