https://bugs.freedesktop.org/show_bug.cgi?id=110865
--- Comment #4 from Alex Deucher alexdeucher@gmail.com --- (In reply to Martin from comment #3)
Thank you for your explanation. How do I find out the blanking periods?
They are based on the timing for the mode on the display. As for the relevant driver code, take a look at smu7_apply_state_adjust_rules().