drm/amd/display: Add version check before using DP alt query interface
authorNicholas Kazlauskas <nicholas.kazlauskas@amd.com>
Thu, 16 Dec 2021 16:19:30 +0000 (11:19 -0500)
committerAlex Deucher <alexander.deucher@amd.com>
Fri, 7 Jan 2022 22:22:01 +0000 (17:22 -0500)
commit19e43f1276b38716ad558c2018535e475cb9f3cf
treee7911478da8c7ca3180d58f57828f12b949a2da5
parent214993e106ea84a82e2c644bff3dbbe601b11e04
drm/amd/display: Add version check before using DP alt query interface

[Why]
To maintain compatibility with firmware older than 4.0.11.

Those firmware may have interrmittent hangs with RDCSPIPE or the PHY,
but we shouldn't regress their previous behavior.

[How]
Use the new path if firmware is development or 4.0.11 or newer. Use the
legacy path otherwise.

Fixes: 41f91315b5be5a ("drm/amd/display: Query DMCUB for dp alt status")

Tested-by: Daniel Wheeler <daniel.wheeler@amd.com>
Reviewed-by: Hansen Dsouza <hansen.dsouza@amd.com>
Acked-by: Rodrigo Siqueira <Rodrigo.Siqueira@amd.com>
Signed-off-by: Nicholas Kazlauskas <nicholas.kazlauskas@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
drivers/gpu/drm/amd/display/dc/dcn31/dcn31_dio_link_encoder.c