If you drive to the resort, they will sometimes ask for your ADR# at the guard shack, so be sure to have it handy. They may also give you a parking pass for a limited time in the resort parking lot (typically three hours). It's extremely rare for them to not let you park at the resort if you have an ADR. In all my years of going to Disney resorts to eat, it's only happened to me once, when they had two conventions booked at CR and I had an ADR at Concourse Steakhouse. With the meeting attendees and resort guests, they didn't have enough parking. Even with the ADR, they made me leave and park in the TTC lot.