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Commit c2b2641e authored by Nicholas Kazlauskas's avatar Nicholas Kazlauskas Committed by Greg Kroah-Hartman
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drm/amd/display: Fix 4to1 MPC black screen with DPP RCO

commit bf224e00

 upstream.

[Why]
DPP Root clock optimization when combined with 4to1 MPC combine results
in the screen turning black.

This is because the DPPCLK is stopped during the middle of an
optimize_bandwidth sequence during commit_minimal_transition without
going through plane power down/power up.

[How]
The intent of a 0Hz DPP clock through update_clocks is to disable the
DTO. This differs from the behavior of stopping the DPPCLK entirely
(utilizing a 0Hz clock on some ASIC) so it's better to move this logic
to reside next to plane power up/power down where we gate the HUBP/DPP
DOMAIN.

The new  sequence should be:
Power down: PG enabled -> RCO on
Power up: RCO off -> PG disabled

Rename power_on_plane to power_on_plane_resources to reflect the
actual operation that's occurring.

Cc: stable@vger.kernel.org
Cc: Mario Limonciello <mario.limonciello@amd.com>
Reviewed-by: default avatarJun Lei <Jun.Lei@amd.com>
Acked-by: default avatarQingqing Zhuo <qingqing.zhuo@amd.com>
Signed-off-by: default avatarNicholas Kazlauskas <nicholas.kazlauskas@amd.com>
Tested-by: default avatarDaniel Wheeler <daniel.wheeler@amd.com>
Signed-off-by: default avatarAlex Deucher <alexander.deucher@amd.com>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent cc994284
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