How to set up my raspberry to communicate with QGC?

Hello guys! I downloaded a image from the official website of Raspberry(Raspberry Pi OS – Raspberry Pi).
Now what I shoud set up could make my raspberry communicate with pixhawk and QGC! Thank you all!

Hi you can go to https://www.ardusub.com and follow introduction
When you used ardusub rasbian image
Pixhawk automatically connect to raspberry pi

Thank you Volley! I have read this guide book, but I just want to finish seting up by myself, because I plan to use TK1 to take place of raspberry! Do you have a good idea?

Ok, you can install mavlink on your raspberry pi
This link can be help you
http://ardupilot.org/dev/docs/raspberry-pi-via-mavlink.html