Dear Sir,
StellarIP have an early Vivado projects but only if the firmware itself supports it. And so far we are not preparing firmwares for Vivado except for large Virtex 7 FPGA as the 1140t because they are not support on ISE.
The ultrascale platforms we are using also are on Vivado because ultrascale are not supported on ISE.
We have no plan on back porting all our firmware to Vivado.
This being said, StellarIP creates an ISE project and Xilinx have a lot of literature and training on how to convert an ISE project to Vivado flow.
Best Regards,
Arnaud