Hi ! I'm trying to configure my secure monitor so that:
- the secure world does not have access to any floating-point hardware
- the normal world can do whatever it wants
To this purpose, I allow the normal world to use the relevant registers by configuring CPACR and NSACR.
In order to prevent the Secure world to use the relevant registers & operation, I want to:
- when switching from NS -> S: save the value of FPEXC, and set FPEXC[EN] to 0
- when switchting from S -> NS: restoring the value of FPEXC
Will this be enough to prevent any fp operation in the Secure world, while allowing a normal usage in the NW ?
Best,
V.