OP-TEE on imx8m mini

[borisshapiro]

Hi.

I am trying to run secure hello-world example on imx8m-mini without success.
My board is from variscite running Linux kernel 4.14.78. I followed instruction to compile tee-supplicant and hello-world host and secure examples.

Running tee-supplicant gives me the error:

./tee-supplicant
ERR [11475] TSUP:main:694: failed to find an OP-TEE supplicant device

In my kernel configuration I have:

CONFIG_TEE=y
# TEE drivers
CONFIG_OPTEE=y

And in Device tree I added:

firmware {
      optee {
          compatible = "linaro,optee-tz";
          method = "smc";
      };
  };

When system boots I see no /dev/tee in /dev folder and dmesg output is:

optee: probing for conduit method from DT.
optee: api uid mismatch

I tried changing "smc" to "hvc" in device tree method, but the result is the same.

How can I fix this so I can run the code hello-world examples?

[djoh]

Sorry for posting again, but I'm not able to edit my previous post anymore (time expired!?).

BTW: According to NXPs "i.MX Porting Guide", the device tree node for optee on i.MX8 processors is added dynamically by u-boot, so you're not meant to patch the devicetree manually.

[djoh]

Hello,

just in case anyone else has this problem and finds this thread, this worked for me with Variscite VAR-SOM-MX8M-MINI, Yocto Warrior 2.7 and kernel 4.19.35:

I added " optee" by a MACHINE_FEATURES_append statement in “local.conf”. (Don't make the same mistake as me and put it in a recipe, as this will probably result in “imx-atf” and “imx-boot” builds without optee support, due to delayed statement evaluation.)
DISTRO_FEATURES of the fsl distro should contain "optee" by default, so "optee" ends up in COMBINED_FEATURES and all modifications for this feature are applied.

After modprobing the kernel module, xtest runs without problems.

Best regards
djoh

[diegoadrian]

Hello,

Unfortunately, we cannot provide support for the Variscite BSP. Since is a different one that we currently support for our Boards. I suggest you is to submit a ticket with Variscite.

Variscite Support Center - Variscite 

I apologize for the inconveniences this could give you.

Best regards,

Diego.