In Fast Models 11.15 Base Rev C FVP Release Notes, it says,
The model also supports Armv9 features mentioned below: - Realm Management Extension (RME) at Beta quality - Branch Record Buffer Extension (BRBE) at EAC quality
But I have not found RME in FVP, how can I test RME in FVP?
You can dump the parameters that the simulator takes, and seach for RME and BRBE.
FVP_Base_RevC-2xAEMvA -l > params.txt
# Look for has_rme, has_brbe