I notice you have a xilibs directory for "Xilinx simulation models". You should be pleased to find out that Xilinx have released their models under an Apache 2.0 licensed at https://github.com/Xilinx/XilinxUnisimLibrary and we are working to make them compatible with then open source simulation tools at https://github.com/SymbiFlow/XilinxUnisimLibrary