Preheat oven to 350 degrees. Butter a 9-inch pie plate.
In a large bowl, gently combine berries with ¼ cup sugar, ¼ cup flour and the cinnamon. Transfer to prepared pie plate.
In a medium bowl, combine rolled oats, remaining ½ cup flour and remaining ½ cup sugar, the brown sugar and salt. Use pastry blender or two knives to work in the cold butter, until mixture resembles a coarse meal. Sprinkle evenly over berries.
Place pie plate on a baking sheet and bake in center of preheated oven until fruit is bubbling and topping is golden brown, about 1 hour.
Remove crisp to a rack to cool slightly.
Serve bowls topped with whipped cream or vanilla ice cream.
