set_timer_irq
int (*set_timer_irq)(struct hw *hw, int enable);
.set_timer_irq = set_timer_irq,
.set_timer_irq = set_timer_irq,
hw->set_timer_irq(hw, 1);
hw->set_timer_irq(hw, 0);
if (!use_system_timer && hw->set_timer_irq) {