Yes, Kami and Piccolo were originally a single being. That Namekian expelled all of the evil from himself, which became a separate being called King Piccolo. The good part of the original Namekian that remained was then called Kami. In the original Dragonball series when Goku was a kid, King Piccolo tried conquering the world and Goku killed him after being trained by Kami. Before King Piccolo died, he spit out an egg to essentially reincarnate himself, and that egg became the Piccolo we know today.