Hi Sasha, 
On Thu, Jun 13, 2019 at 01:11:41PM -0400, Sasha Levin wrote:

On Wed, Jun 05, 2019 at 04:39:36PM +0530, Sumit Garg wrote:

quoted

On Wed, 5 Jun 2019 at 01:39, Sasha Levin [off-list ref] wrote:

quoted

On Tue, Jun 04, 2019 at 11:45:52AM +0530, Sumit Garg wrote:

quoted

On Thu, 30 May 2019 at 20:58, Sasha Levin [off-list ref] wrote:

quoted

+       /* Open context with TEE driver */
+       pvt_data->ctx = tee_client_open_context(NULL, ftpm_tee_match, NULL,
+                                               NULL);
+       if (IS_ERR(pvt_data->ctx)) {
+               dev_err(dev, "%s:tee_client_open_context failed\n", __func__);

Is this well tested? I see this misleading error multiple times as
follows although TEE driver works pretty well.

Yes, this was all functionally tested.

I did test as well with a DeveloperBox, i can confirm the driver is loading (but
i have no fTPM support on the OP-TEE side for now)


apalos@mule:~>sudo dmesg | grep optee
[sudo] password for apalos: 
[    5.035801] optee: probing for conduit method from DT.
[    5.041045] optee: revision 3.2 (53bf1c38)
[    5.041772] optee: initialized driver
apalos@mule:~>sudo dmesg | grep tpm
[    5.000674] ftpm-tee tpm@0: ftpm_tee_probe:tee_client_open_context failed
[    5.101655] ftpm-tee tpm@0: ftpm_tee_probe:tee_client_open_session failed,
err=ffff000c
[    5.109703] ftpm-tee: probe of tpm@0 failed with error -22


The error -22 is nice since the probe eventually failed (no fTPM support in
secure world). Can we slightly change the
'ftpm_tee_probe:tee_client_open_context failed' and indicate this is not a real
error since the probe gets deferred untill Secure world is alive?

By the way there is *real* interest for this functionality. I expect to run it
on a number of Arm boards once i get some free time.

quoted

Can you share your build instructions and testing approach?

Yes: it looks like you got all the kernel bits, but not the firmware.
There are instructions for it here: https://github.com/microsoft/ms-tpm-20-ref

Once it's running, you can test it by running your favorite TPM usecases
through /dev/tpm0.

--
Thanks,
Sasha

Thanks
/Ilias