Hello @sens118,
not sure if I understand what issue are you facing when programming FPGA via JTAG?
As described in GitHub repo you will need PCIe Adapter to access JTAG chain, because LimeSDR-XTRX itself does not have JTAG header, only exposed pads.
When you have JTAG cable connected - it is standard programming procedure in Vivado software as for any other Xilinx device.