For the software side: All of the games demoed were using DXR (DirectX Raytracing) for which RTX is just a backend for. DXR works on any recent AMD GPU (albeit slowly due to the lack of dedicated hardware) and AMD was a hardware partner in development of DXR.

For the hardware side: AMD has not said anything about specialized hardware for ray tracing. They almost certainly have known about it for quite a while but nobody (publicly at least) knows if they ever started on this.