My father makes a point of getting up at 6 even in winter.
Literal
Father [topic-は] winter [even in-でも] 6-o'clock [at-に] get-up [decided habit-ことにしている].
冬でも (even in winter) uses でも for concession. ~ことにしている marks a personal decision maintained as a habit. 起きる at a fixed time regardless of season shows discipline.