Hi ,
I am asking if there is a way for a TA in the OP-TEE to directly communicate with M-33 via the message unit. It would seem that the message unit which binds the M-33 to the AD can be allocated to the secure world via the resource manager. So, In theory a TA could send a message to the M-33. (I am not asking the M-33 to call a TA)
However it seems this is not really possible or supported by NXP.
"
OP‑TEE is designed as a Trusted Execution Environment (TEE) running alongside a rich OS such as Linux on the Cortex‑A cores. Communication with OP‑TEE normally relies on Secure Monitor Calls (SMCs) from the non‑secure Cortex‑A world.
The M33 core does not have the ability to issue SMCs, so it cannot directly invoke OP‑TEE services.
Some projects (e.g. NuttX) offer an OP‑TEE driver that communicates over RPMsg, allowing a remote processor to interact with OP‑TEE. Linux kernel work is also ongoing on a “remoteproc TEE driver” to authenticate and load firmware for remote cores. These solutions, however, are not yet part of NXP’s official i.MX 8ULP BSP and are mainly intended for firmware management rather than general-purpose service calls."
does that mean that OP-TEE => M-33 is possible using NuttX or similar drivers? Note that ideally we would like one way message OP-TEE => M-33 (request and response if the messaging allows that)
