For our custom board based on imx6ulevk with yocto/Freescale branch: 4.14.98_2.0.0_ga we have Optee-os working, it boots and we can launch client apps through OPTEE.
The next step is to access devices securely through OPTEE (I2C / SPI). We have integrated the drivers and also registered the secure memory for the peripheral bus and initialized the driver at boot.
Unfortunately when we try to start an I2c or spi transaction the system panics and freezes.
We checked the mmu for the virtual address to physical address and they are correct.
We think the ARM trustzone kicks in and refuses the access to the peripheral(s) but we do not know where to set the access/policy control bits.
Does anybody know how to get peripheral access working within OPTEE-OS? or where to look to get things working.
Good to know: We start uboot (non secure/ no HAB at this moment / no SPL) and jumps to OPTEE-OS after that, followed by the Linux kernel.