imx6ull optee peripheral access control UART or GPIO

[Karun]

Hello,

I have optee-examples running on imx6ull board. also xtest pass all test.

Now I want to implement access control for  UART or GPIO.

only TA can send/receive data over UART, 

or TA can toggle GPIO.

other then that it is not allowed to do so.

I searched online/NXP forum a lot about that, but could not get any help to get start.

Is there any reference or guide available?

[Bio_TICFSL]

Hello,

NXP don't have a reference for your design but you can check the current state of the system's GPIOs can be obtained in user-mode, as shown in the following example:

cat /sys/kernel/debug/gpio

Check this note from our third party Variscite:

https://variwiki.com/index.php?title=MX8M_GPIO

Regards