Where can I find clock mux?

Thank you very much,Rysc.

Compared to the first way you stated, I think the other one may run at higher speed. Use pll to create all the frequencies i need, but the pll only can create 3 frequencies sometimes only two different frequencies . I need four different frequencies used as clock, can I use more than one Pll to create the clock i need ? (Of course the input clock is the same one)

In my opinion (if i understand you correctly)what your suggestion is to avoid the design fabric as i described in my post, is it?

In order to get a higher speed such as more than 400M , I can't find a better way to deal with the problerm i mentioned on my post with the cyclone series.