I am having some troubles adding OP-TEE support to an i.MX8MM board. We are using the meta-freescale layer to provide optee recipes, along with a custom layer which provides a u-boot recipe.
I managed to get optee binaries installed, mainly using this presentation: https://timesys.com/webinars/Secure-by-Design-NXP-Webinar-Series-OP-TEE.pdf. The only thing left is getting /dev/tee* device to work, since for now it isn't even present. I tried to add a firmware node to the device tree in uboot-venice/arch/arm/dts/imx8mm.dtsi, and multiple other files in u-boot, but to no avail. I even checked that a .dtb file produced by yocto contains an optee node, but after booting the system it is not present.
I also tried inserting the firmware node to the system directly, in its own device tree, but then dmesg showed optee: api uid mismatch, which tells me that it should be added in u-boot.
Do you have any ideas what could be the cause of this problem?
For more details about the installation I share the i.MX Porting Guide, chapter 5 is the configuration of OP-TEE
And the OP-TEE documentation, in the build and run section