How to use Connectx-6 dx Data at rest feature

The data sheet for the connectx6 dx card ) references Data-at-rest AES-XTS encryption and decryption.
I am having problems finding information on how to use this feature.
I did not find any references to data at rest in the MLNX_EN documentation or the ConnectX-6 card user’s manual. Does anyone know where I can find more information on this feature and in what configuration it can be used under?

I am using the connectx-6 DX cards in Supermicro server running Oracle Linux 8.5.

We do not have the API as GA yet, but we can go in to POC in a few months.