。
Dinner's ready.
Literal
Evening-rice [subject-が] become-done-[polite-past-ました].
夕御飯 (ゆうごはん) is one of several 'dinner' synonyms: 夕 (evening) + 御飯 (cooked rice, meal). The 御- is honorific, making it a slightly gentler or more polite form than 夕飯. The trio 夕食 / 夕飯 / 夕御飯 covers the register range — 夕食 is neutral/formal, 夕飯 is warm/homey, 夕御飯 is polite-warm.