On Tue, Feb 13, 2024 at 01:30:59PM +0200, Jani Nikula wrote:
> Drop the duplicate read of DP_MSTM_CAP DPCD register, and the duplicate
> logic for choosing MST mode, and store the chosen mode in struct
> intel_dp. Rename intel_dp_configure_mst() to intel_dp_mst_configure()
> while at it.
>
> Cc: Arun R Murthy <arun.r.mur...@intel.com>
> Cc: Ville Syrjälä <ville.syrj...@linux.intel.com>
> Signed-off-by: Jani Nikula <jani.nik...@intel.com>
> ---
> .../drm/i915/display/intel_display_types.h | 1 +
> drivers/gpu/drm/i915/display/intel_dp.c | 23 ++++++++-----------
> 2 files changed, 11 insertions(+), 13 deletions(-)
>
> diff --git a/drivers/gpu/drm/i915/display/intel_display_types.h
> b/drivers/gpu/drm/i915/display/intel_display_types.h
> index 01eb6e4e6049..4a8440a3a812 100644
> --- a/drivers/gpu/drm/i915/display/intel_display_types.h
> +++ b/drivers/gpu/drm/i915/display/intel_display_types.h
> @@ -1780,6 +1780,7 @@ struct intel_dp {
>
> bool is_mst;
> int active_mst_links;
> + enum drm_dp_mst_mode mst_detect;
>
> /* connector directly attached - won't be use for modeset in mst world
> */
> struct intel_connector *attached_connector;
> diff --git a/drivers/gpu/drm/i915/display/intel_dp.c
> b/drivers/gpu/drm/i915/display/intel_dp.c
> index 007cb2a04e38..72e91322e310 100644
> --- a/drivers/gpu/drm/i915/display/intel_dp.c
> +++ b/drivers/gpu/drm/i915/display/intel_dp.c
> @@ -4039,11 +4039,10 @@ intel_dp_mst_detect(struct intel_dp *intel_dp)
> struct drm_i915_private *i915 = dp_to_i915(intel_dp);
> struct intel_encoder *encoder = &dp_to_dig_port(intel_dp)->base;
> enum drm_dp_mst_mode sink_mst_mode;
> - enum drm_dp_mst_mode mst_detect;
>
> sink_mst_mode = drm_dp_read_mst_cap(&intel_dp->aux, intel_dp->dpcd);
>
> - mst_detect = intel_dp_mst_mode_choose(intel_dp, sink_mst_mode);
> + intel_dp->mst_detect = intel_dp_mst_mode_choose(intel_dp,
> sink_mst_mode);
>
> drm_dbg_kms(&i915->drm,
> "[ENCODER:%d:%s] MST support: port: %s, sink: %s, modparam:
> %s -> enable: %s\n",
> @@ -4051,25 +4050,23 @@ intel_dp_mst_detect(struct intel_dp *intel_dp)
> str_yes_no(intel_dp_mst_source_support(intel_dp)),
> intel_dp_mst_mode_str(sink_mst_mode),
> str_yes_no(i915->display.params.enable_dp_mst),
> - intel_dp_mst_mode_str(mst_detect));
> + intel_dp_mst_mode_str(intel_dp->mst_detect));
>
> - return mst_detect != DRM_DP_SST;
> + return intel_dp->mst_detect != DRM_DP_SST;
> }
>
> static void
> -intel_dp_configure_mst(struct intel_dp *intel_dp)
> +intel_dp_mst_configure(struct intel_dp *intel_dp)
> {
> - struct drm_i915_private *i915 = dp_to_i915(intel_dp);
> - bool sink_can_mst = drm_dp_read_mst_cap(&intel_dp->aux, intel_dp->dpcd)
> == DRM_DP_MST;
> -
> if (!intel_dp_mst_source_support(intel_dp))
> return;
I was wondering if we even need that, but it looks to be just a
check to see if we actually initialized the mst_mgt or not.
We should probably rename it or something... Or perhaps we could
tweak the topology manager a bit so we wouldn't need to check...
>
> - intel_dp->is_mst = sink_can_mst &&
> - i915->display.params.enable_dp_mst;
> + intel_dp->is_mst = intel_dp->mst_detect != DRM_DP_SST;
> +
> + drm_dp_mst_topology_mgr_set_mst(&intel_dp->mst_mgr, intel_dp->is_mst);
>
> - drm_dp_mst_topology_mgr_set_mst(&intel_dp->mst_mgr,
> - intel_dp->is_mst);
> + /* Avoid stale info on the next detect cycle. */
> + intel_dp->mst_detect = DRM_DP_SST;
Hmm. Not sure I like having ephemeral stuff like this in intel_dp,
but I guess the alternative would be plumb it up from detect_dpcd()
by hand, which might not be super pretty either. Oh well.
Reviewed-by: Ville Syrjälä <ville.syrj...@linux.intel.com>
> }
>
> static bool
> @@ -5739,7 +5736,7 @@ intel_dp_detect(struct drm_connector *connector,
>
> intel_dp_detect_dsc_caps(intel_dp, intel_connector);
>
> - intel_dp_configure_mst(intel_dp);
> + intel_dp_mst_configure(intel_dp);
>
> /*
> * TODO: Reset link params when switching to MST mode, until MST
> --
> 2.39.2
--
Ville Syrjälä
Intel
