Preheat oven to 325°F. Grease bottom and sides of 9-inch springform pan. Combine cornmeal and chili powder; sprinkle over bottom and sides of prepared pan.
Beat cream cheese, eggs, garlic powder and cumin in large bowl until smooth. Stir in chiles and 1/2 cup green onion. Pour half of batter into pan. Spoon 1 cup salsa over batter. Sprinkle 1 1/2 cups cheddar cheese over salsa. Spread remaining batter over cheese.
Bake for 55 to 60 minutes or until edges are set but center still moves slightly. Cool completely on wire rack or in refrigerator; remove side of springform pan. Spread remaining salsa on top; sprinkle with remaining cheese and green onion. Serve with corn chips.