Heat 2 tablespoon oil in a large heavy skillet over medium-high heat until it shimmers, then sauté garlic until pale golden, about 30 seconds. Stir in panko, almonds, rosemary, 1/2 teaspoon pimentón, 1/4 teaspoon salt, and 1/8 teaspoon pepper. Transfer to a large plate.
Stir together Madeira, remaining 2 tablespoons oil and 2 teaspoons pimentón, and 1/4 teaspoon each of salt and pepper in a shallow dish. Pat pork dry and rub all over with mixture. Pat three fourths of crumbs all over pork, pressing gently to adhere, then sprinkle tops with remaining crumbs.
Roast until an instant-read thermometer inserted diagonally 2 inches into meat registers 145 to 150°F, about 20 minutes. (Check after 15 minutes to see if crumbs are getting too dark; if they are, tent loosely with foil.) Transfer pork to a cutting board. Tent loosely with foil and let stand 10 minutes before slicing.
