Hi,

For Isolation Level 2, ARoT cannot access PRoT data.   If PRoT partition makes a call to ARoT partition, how are the input/output buffers made accessible to the ARoT partition so a transient copy of the data can be made?  I looked at the AN521 implementation of tfm_hal_activate_boundary() and it does add any MPU regions to allow unprivileged access under Isolation Level 2.  

For Isolation Level 3, I assume the input/output buffers would need to added to a runtime memory asset to allow unprivileged access.  Is my understanding correct?

Regards,

Brian Quach

SimpleLink MCU

Texas Instruments Inc.

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