Hi Martin, On Mon, 18 Jun 2018 08:20:20 +0000, "Hecht, Martin (Avnet Silica)" <[email protected]> wrote:
> Hi Miquel, > > > -----Original Message----- > > From: Miquel Raynal [mailto:[email protected]] > > Sent: Montag, 18. Juni 2018 10:05 > > To: Hecht, Martin (Avnet Silica) <[email protected]> > > Cc: [email protected]; [email protected] > > Subject: Re: [U-Boot] tpm TIS TPMv2.0 > > > > Hi Martin, > > > > On Fri, 15 Jun 2018 13:34:07 +0000, "Hecht, Martin (Avnet Silica)" > > <[email protected]> wrote: > > > > > Hi Miquel, Simon, > > > > > > 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. > 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. > On the other hand what about to use a xfer what > can handle all three cases (in, out, in/out)? As I did not implement any TPM command that needed it I did not care about it. Of course if there is a need for it: it should be implemented too. I contributed only basic support for essential commands (measured boot, mainly) but please feel free to enhance the code to add more features! Regards, Miquèl _______________________________________________ U-Boot mailing list [email protected] https://lists.denx.de/listinfo/u-boot
