See PxrDisplace for how to add scalar and vector displacement as well as displacement layers.
Add a PxrDisplace VOP to your RIS Network. Wire your displacement map such as creating a PxrTexture VOP or PxrPtexture VOP for textture or ptex respectively. We can wire a shading network also.
Wire your PxrDisplace VOP to the rman__displacement input of the PxrCollect material.
Displacement settings are found on the RenderMan tab > Primvars > Shading > Displacement on the geometry OBJ being displaced.
