Use the RPM_GRID system for heterogeneous RPMs in which cells belong to different site types (such as a combination of slice, block RAM, and DSP). This system provides absolute coordinates mapped to a specific AMD device.
Because cells can occupy sites of different sizes, the RPM_GRID system uses absolute RPM_GRID coordinates. You can view RPM_GRID values in the Site Properties window of the Vivado IDE when you select a site. You can also query them with Tcl commands using the RPM_X and RPM_Y site properties.