| eed4edda | 20-Dec-2023 |
Robin Chen <[email protected]> |
drm/amd/display: Support long vblank feature
[WHY] We want to support low hz case, but the original vtotal/vtotal_min/vtotal_max can't support more than 0x7FFF.
[HOW] We use the 2 HW reg to contorl
drm/amd/display: Support long vblank feature
[WHY] We want to support low hz case, but the original vtotal/vtotal_min/vtotal_max can't support more than 0x7FFF.
[HOW] We use the 2 HW reg to contorl long vblank case. 1. OTG_V_COUNT_STOP_CONTROL -> vcount_stop 2. OTG_V_COUNT_STOP_CONTROL2 -> vcount_stop_timer
vcount_stop define from which line we stop using vcount and start using vcount2. vcount_stop_timer define how long we use vcount2.
Ex: Vtotal = 7 OTG_V_COUNT_STOP_CONTROL = 4 OTG_V_COUNT_STOP_CONTROL2 = 5
time : 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11 vcount : 0, 1, 2, 3, - - - - - 4, 5, 6 vcount2 : 0, 1, 2, 3, 4,
Reviewed-by: Jun Lei <[email protected]> Acked-by: Alex Hung <[email protected]> Signed-off-by: ChunTao Tso <[email protected]> Signed-off-by: Robin Chen<[email protected]> Tested-by: Daniel Wheeler <[email protected]> Signed-off-by: Alex Deucher <[email protected]>
show more ...
|