Nios2 Flash Problem

I use the SST39VF320 flash on my custom board with a EP2C35F672C8, it's a 4M bytes and 16 bits flash and supports CFI.

In the sopc buider, I chose the cfi flash ,and set the address width to 21, data width to 16. the size show below is 4M bytes.

After the generation, I found the address width is 22 in the quartus project.So I shift the bus by one , A1 from the fpga to the A0 on the flash side.Is that right?

However, the flash doesn't work.I can't open flash in the software using the api nor program in the flash programer.It seems nios got the wrong basic information about the flash in the system init time,because console shows that the erase region is just half of the size of th flash during the program.

My software version is both 5.1, is there any one know how to fix the problem?