Commit a92e390e authored by Imre Deak's avatar Imre Deak Committed by Joonas Lahtinen
Browse files

drm/i915/dp_mst: Use the correct connector while computing the link BPP limit on MST 



Atm, on an MST link in DSC mode
intel_dp_compute_config_link_bpp_limits() calculates the maximum link
bpp limit using the MST root connector's DSC capabilities. That's not
correct in general: the decompression could be performed by a branch
device downstream of the root branch device or the sink itself.

Fix the above by passing to intel_dp_compute_config_link_bpp_limits()
the actual connector being modeset, containing the correct DSC
capabilities.

Cc: Ankit Nautiyal <ankit.k.nautiyal@intel.com>
Fixes: 1c5b72da ("drm/i915/dp: Set the DSC link limits in intel_dp_compute_config_link_bpp_limits")
Reviewed-by: default avatarAnkit Nautiyal <ankit.k.nautiyal@intel.com>
Reviewed-by: default avatarLuca Coelho <luciano.coelho@intel.com>
Signed-off-by: default avatarImre Deak <imre.deak@intel.com>
Link: https://lore.kernel.org/r/20250509180340.554867-2-imre.deak@intel.com


(cherry picked from commit 266e2fcf)
Signed-off-by: default avatarJoonas Lahtinen <joonas.lahtinen@linux.intel.com>
parent 1faeeb31

drivers/gpu/drm/i915/display/intel_dp.c

+4 −3
Original line number Diff line number Diff line
@@ -2524,6 +2524,7 @@ intel_dp_dsc_compute_pipe_bpp_limits(struct intel_dp *intel_dp, 


bool

intel_dp_compute_config_limits(struct intel_dp *intel_dp,

			       struct intel_connector *connector,

			       struct intel_crtc_state *crtc_state,

			       bool respect_downstream_limits,

			       bool dsc,
@@ -2577,7 +2578,7 @@ intel_dp_compute_config_limits(struct intel_dp *intel_dp, 
	intel_dp_test_compute_config(intel_dp, crtc_state, limits);



	return intel_dp_compute_config_link_bpp_limits(intel_dp,

						       intel_dp->attached_connector,

						       connector,

						       crtc_state,

						       dsc,

						       limits);
@@ -2638,7 +2639,7 @@ intel_dp_compute_link_config(struct intel_encoder *encoder, 
	joiner_needs_dsc = intel_dp_joiner_needs_dsc(display, num_joined_pipes);



	dsc_needed = joiner_needs_dsc || intel_dp->force_dsc_en ||

		     !intel_dp_compute_config_limits(intel_dp, pipe_config,

		     !intel_dp_compute_config_limits(intel_dp, connector, pipe_config,

						     respect_downstream_limits,

						     false,

						     &limits);
@@ -2672,7 +2673,7 @@ intel_dp_compute_link_config(struct intel_encoder *encoder, 
			    str_yes_no(ret), str_yes_no(joiner_needs_dsc),

			    str_yes_no(intel_dp->force_dsc_en));



		if (!intel_dp_compute_config_limits(intel_dp, pipe_config,

		if (!intel_dp_compute_config_limits(intel_dp, connector, pipe_config,

						    respect_downstream_limits,

						    true,

						    &limits))

drivers/gpu/drm/i915/display/intel_dp.h

+1 −0
Original line number Diff line number Diff line
@@ -194,6 +194,7 @@ void intel_dp_wait_source_oui(struct intel_dp *intel_dp); 
int intel_dp_output_bpp(enum intel_output_format output_format, int bpp);



bool intel_dp_compute_config_limits(struct intel_dp *intel_dp,

				    struct intel_connector *connector,

				    struct intel_crtc_state *crtc_state,

				    bool respect_downstream_limits,

				    bool dsc,

drivers/gpu/drm/i915/display/intel_dp_mst.c

+3 −2
Original line number Diff line number Diff line
@@ -599,12 +599,13 @@ adjust_limits_for_dsc_hblank_expansion_quirk(struct intel_dp *intel_dp, 


static bool

mst_stream_compute_config_limits(struct intel_dp *intel_dp,

				 const struct intel_connector *connector,

				 struct intel_connector *connector,

				 struct intel_crtc_state *crtc_state,

				 bool dsc,

				 struct link_config_limits *limits)

{

	if (!intel_dp_compute_config_limits(intel_dp, crtc_state, false, dsc,

	if (!intel_dp_compute_config_limits(intel_dp, connector,

					    crtc_state, false, dsc,

					    limits))

		return false;