Q: Is an AXI reference design for Digilent Genesys available or at least planned?
No, it is not available and cannot be planned.
The Digilent Genesys board carries a Xilinx Virtex-5 FPGA, which is not compatible with the AXI bus. AXI (Advanced eXtensible Interface) is available only on 6th generation Xilinx FPGAs or newer (Spartan-6, Virtex-6, Virtex-7, etc.). If a user insists on using AXI, he/she will need to purchase a newer board than Digilent Genesys. Also note that even with the PLB based design, the Genesys with its Xilinx Virtex-5 will outperform a Xilinx Spartan-6 with an AXI based design.
Please find some more general information here:
http://forums.xilinx.com/t5/EDK-and-Platform-Studio/About-AXI-Interface-in-Virtex-5/td-p/133574