Stratix IV GX Dev Kit: Config FPGA with Flash

I have a Stratix IV GX dev kit.

The "My First FPGA Design Tutorial" works well on my dev board.

However, I want to config FPGA by flash, but cannot find a way.

I tried to convert .sof to .pof with FPP (Fast Passive Parallel x 8) mode, but not able to write into my flash.

I also want to generate .flash by NIOS II EDS (this method is provided in Stratix IV Devkit user guide), but sof2flash not work at all...

Please give me a help.

Thank you.