You're the pack leader- you tell the dog where he's allowed to crap, and if you want it in the driveway, hey, it's in the driveway. But as he's maturing the pissing/marking thing is still a really useful behavior to use for training, because he's going to be leaving scent marks around the yard, not only pissing because he's got to pee. So again, take him out on the leash and walk him around the edge of your property, and praise him for taking interest in things and marking them. He's making himself a dog version of an invisible fence! It won't keep him from crossing it, but that part is up to you to train him.