What are the input and output capacitance values for a particular device package combination?
The DC and Switching Characteristics Data Sheet lists a maximum "Cin" value (for example& 10 pF) based on device characterization.
You can find capacitance values that stem from process models in the IBIS file.
"C_pkg" is a lumped approximation of the package capacitance, and "C_comp" is the capacitance of the die.
For rough calculations, you can add these values to determine the total pin capacitance.
To accurately model the behavior of any signal, you should perform IBIS simulation.
IBIS models for Xilinx devices can be found at the following link:
Select Device Model, IBIS Models then the required Family.