What does the ordering part number of Xilinx devices mean?
How can I find the Xilinx device family from a part number?
What does each portion of the part mark on a Xilinx device mean?
This information is available in chapter 1 of the Device Package User Guide (UG112) under the section titled "Part Marking":
https://www.xilinx.com/support/documentation/user_guides/ug112.pdf
To determine valid ordering combinations for a given device, consult the device data sheet.
Data sheets and (UG112) can be selected on the following website:
https://www.xilinx.com/support.html#documentation