test verilog codes at https://github.com/bsh-git/bsh_hdl_lib using Vivado 2017.4 and ZedBoard
Run the Tcl scripts procject_test_foo.tcl to create Vivado project test_foo.
% source /opt/Xilinx/Vivado/2017.4/settings64.sh
% vivado -mode batch -source project_test_pwm.tcl
% vivado test_pwm/test_pwm.xpr