spi interfacing of ADF4156

i am doing a project 'hardware implementation of DPLL using VHDL'. We are using the IC ADF4156 as the phase detector. the inputs to the registers are given as serial inputs from FPGA. we hav five registers in ADF4156 and we hav got a set of values to input the registers . hw can we do this by spi interfacing? or can i do this in any other way?

No answers?
Anybody?
Please help.