Hi Nick,
No, you do not need to do any thing to enable MMAU. To minimize power dissipation, the design supports an architectural clock gate for the entire module, that is, the MMAU is only clocked when responding to bus requests to its programming model or is busy performing a calculation.
There is a MMAU demo in KM34 sdk, please find it in \boards\twrkm34z75m\driver_examples\mmau.
Regards,
Jing