Gather all ingredients.

Preheat oven to 350 degrees F (175 degrees C).

Crush garlic with rosemary, salt, and pepper in a mortar and pestle to make a paste.

Pierce meat with a sharp knife in several places and press garlic paste into the openings. Rub pork loin with the remaining garlic mixture and olive oil. Set into an oven-safe pan.

Place pork loin into the preheated oven, turning and basting with pan liquids every 30 minutes. Cook until the pork is no longer pink in the center, 90 minutes to 2 hours. An instant-read thermometer inserted into the center should read 145 degrees F (63 degrees C). Remove roast to a platter and keep warm.

Place pan onto the stove over medium-high heat and pour wine into it. Heat wine and stir to loosen browned bits from the bottom of the pan. Simmer for 3 to 5 minutes.

Slice pork loin and serve with pan juices.