My girls both go to bed at 7:00 pm, (Elyse is 4 yrs, and Marieke is 22 months). Marieke has one afternoon nap, usually about 2 hours. They generally get up around 7:00-7:30am. However, my sister's little girl goes to bed at 8:00-8:30pm, and gets up at 6:30-7:00am, and has a 1 hour nap. She is 27 months old. Just a different nature, I guess.
Is your little one possibly responding to the increase in daylight? (You are heading into spring, right? - We're just getting into fall here.) I know my girls had quite a hard time sleeping once the sun started coming up earlier. Good blinds might help.
Otherwise, as the others have suggested, maybe encourage a little quiet play until a more reasonable hour. Keep the lights low, speak softly, give him a board book, or favourite toy, maybe a dry nappy if that's needed, tell him it's too early for getting up, and crawl back in your bed. Hopefully he'll get the idea eventually.