This rule checks whether PLRAM are utilized on the device.
The data from host to device can be moved using global memory, or streaming. The global memory consists of two memory resources: DDR and PL RAM. Each of these memory has an advantage over one other. PLRAM have the advantage of having less read/write LATENCY when using them.
If the buffer size is less than 512 KB, Xilinx recommends using the PL RAM instead of DDR memory as a global memory option.