I believe its 30kmph for freights and 40kmph for passenger trains on the Braganza route (the AEB speed limit). The limits might be the same on the Shiradi route as well considering that it is less steep and has catch sidings.
Earlier the maximum speed on the descent was restricted to 25kmph on the Braganza route. Around 2012, it was 30kmph. I am not aware of any later changes.