[Intel-gfx] [PATCH v4 1/3] drm/i915/dp: Make sure all tiled connectors get added to the state with full modeset

[Matt Roper]

On Mon, Dec 23, 2019 at 02:40:04PM -0800, Manasi Navare wrote:
> In case of tiled displays, all the tiles are linke dto each other
> for transcoder port sync. So in intel_atomic_check() we need to make
> sure that we add all the tiles to the modeset and if one of the
> tiles needs a full modeset then mark all other tiles for a full modeset.
> 
> We also need to force modeset for all synced crtcs after fastset check.
> 
> v5:
> * Rebase
> v4:
> * Fix logic for modeset_synced_crtcs (Ville)
> v3:
> * Add tile checks only for Gen >11
> v2:
> * Change crtc_state scope, remove tile_grp_id (Ville)
> * Use intel_connector_needs_modeset() (Ville)
> * Add modeset_synced_crtcs (Ville)
> * Make sure synced crtcs are forced full modeset
> after fastset check (Ville)
> 
> Suggested-by: Ville Syrjälä <ville.syrjala at linux.intel.com>
> Cc: Ville Syrjälä <ville.syrjala at linux.intel.com>
> Cc: José Roberto de Souza <jose.souza at intel.com>
> Cc: Matt Roper <matthew.d.roper at intel.com>
> Bugzilla: https://gitlab.freedesktop.org/drm/intel/issues/5
> Signed-off-by: Manasi Navare <manasi.d.navare at intel.com>
> ---
>  drivers/gpu/drm/i915/display/intel_display.c | 123 +++++++++++++++++++
>  1 file changed, 123 insertions(+)
> 
> diff --git a/drivers/gpu/drm/i915/display/intel_display.c b/drivers/gpu/drm/i915/display/intel_display.c
> index 94fc4b5bacc0..45a699bac34a 100644
> --- a/drivers/gpu/drm/i915/display/intel_display.c
> +++ b/drivers/gpu/drm/i915/display/intel_display.c
> @@ -14304,6 +14304,118 @@ static bool intel_cpu_transcoder_needs_modeset(struct intel_atomic_state *state,
>  	return false;
>  }
>  
> +static void
> +intel_modeset_synced_crtcs(struct intel_atomic_state *state,
> +			   u8 transcoders)
> +{
> +	struct intel_crtc_state *new_crtc_state;
> +	struct intel_crtc *crtc;
> +	int i;
> +
> +	for_each_new_intel_crtc_in_state(state, crtc,
> +					 new_crtc_state, i) {
> +		if (transcoders & BIT(new_crtc_state->cpu_transcoder)) {
> +			new_crtc_state->uapi.mode_changed = true;
> +			new_crtc_state->update_pipe = false;
> +		}
> +	}
> +}
> +
> +static void
> +intel_atomic_check_synced_crtcs(struct intel_atomic_state *state)
> +{
> +	struct drm_i915_private *dev_priv = to_i915(state->base.dev);
> +	struct intel_crtc_state *new_crtc_state;
> +	struct intel_crtc *crtc;
> +	int i;
> +
> +	if (INTEL_GEN(dev_priv) < 11)
> +		return;
> +
> +	for_each_new_intel_crtc_in_state(state, crtc,
> +					 new_crtc_state, i) {
> +		if (is_trans_port_sync_master(new_crtc_state) &&
> +		    needs_modeset(new_crtc_state)) {
> +			intel_modeset_synced_crtcs(state,
> +						   new_crtc_state->sync_mode_slaves_mask);
> +		} else if (is_trans_port_sync_slave(new_crtc_state) &&
> +			   needs_modeset(new_crtc_state)) {
> +			intel_modeset_synced_crtcs(state,
> +						   BIT(new_crtc_state->master_transcoder));
> +		}
> +	}
> +}
> +
> +static int
> +intel_modeset_all_tiles(struct intel_atomic_state *state, int tile_grp_id)
> +{
> +	struct drm_i915_private *dev_priv = to_i915(state->base.dev);
> +	struct drm_connector *connector;
> +	struct drm_connector_list_iter conn_iter;
> +	int ret = 0;
> +
> +	drm_connector_list_iter_begin(&dev_priv->drm, &conn_iter);
> +	drm_for_each_connector_iter(connector, &conn_iter) {
> +		struct drm_connector_state *conn_state;
> +		struct drm_crtc_state *crtc_state;
> +
> +		if (!connector->has_tile ||
> +		    connector->tile_group->id != tile_grp_id)
> +			continue;
> +		conn_state = drm_atomic_get_connector_state(&state->base,
> +							    connector);
> +		if (IS_ERR(conn_state)) {
> +			ret =  PTR_ERR(conn_state);
> +			break;
> +		}
> +
> +		if (!conn_state->crtc)
> +			continue;
> +
> +		crtc_state = drm_atomic_get_crtc_state(&state->base,
> +						       conn_state->crtc);
> +		if (IS_ERR(crtc_state)) {
> +			ret = PTR_ERR(conn_state);
> +			break;
> +		}
> +		crtc_state->mode_changed = true;
> +		ret = drm_atomic_add_affected_connectors(&state->base,
> +							 conn_state->crtc);
> +		if (ret)
> +			break;
> +	}
> +	drm_connector_list_iter_end(&conn_iter);
> +
> +	return ret;
> +}

This feels like it could be pulled out to a DRM-level helper since
there's nothing really Intel-specific here.  I imagine other drivers
with port sync capabilities will need pretty much exactly the same
logic?  But that can wait until a future patch.

> +
> +static int
> +intel_atomic_check_tiled_conns(struct intel_atomic_state *state)
> +{
> +	struct drm_i915_private *dev_priv = to_i915(state->base.dev);
> +	struct drm_connector *connector;
> +	struct drm_connector_state *old_conn_state, *new_conn_state;
> +	int i, ret;
> +
> +	if (INTEL_GEN(dev_priv) < 11)
> +		return 0;
> +
> +	/* Is tiled, mark all other tiled CRTCs as needing a modeset */
> +	for_each_oldnew_connector_in_state(&state->base, connector,
> +					   old_conn_state, new_conn_state, i) {
> +		if (!connector->has_tile)
> +			continue;
> +		if (!intel_connector_needs_modeset(state, connector))
> +			continue;
> +
> +		ret = intel_modeset_all_tiles(state, connector->tile_group->id);
> +		if (ret)
> +			return ret;
> +	}
> +
> +	return 0;
> +}
> +
>  /**
>   * intel_atomic_check - validate state object
>   * @dev: drm device
> @@ -14331,6 +14443,10 @@ static int intel_atomic_check(struct drm_device *dev,
>  	if (ret)
>  		goto fail;
>  
> +	ret = intel_atomic_check_tiled_conns(state);
> +	if (ret)
> +		goto fail;
> +
>  	for_each_oldnew_intel_crtc_in_state(state, crtc, old_crtc_state,
>  					    new_crtc_state, i) {
>  		if (!needs_modeset(new_crtc_state)) {
> @@ -14378,6 +14494,13 @@ static int intel_atomic_check(struct drm_device *dev,
>  		}
>  	}
>  
> +	/*
> +	 * In case of port synced crtcs, if one of the synced crtcs
> +	 * needs a full modeset, all other synced crtcs should be
> +	 * forced a full modeset.
> +	 */
> +	intel_atomic_check_synced_crtcs(state);
> +

I'm still a bit confused why we don't need to add an additional call to
drm_atomic_helper_check_modeset() here since the two new checks in this
function mess with mode_changed.  I.e., it seems that we're basically
doing exactly what the big kerneldoc warning tells us not to do?


Matt

>  	for_each_oldnew_intel_crtc_in_state(state, crtc, old_crtc_state,
>  					    new_crtc_state, i) {
>  		if (needs_modeset(new_crtc_state)) {
> -- 
> 2.19.1
> 

-- 
Matt Roper
Graphics Software Engineer
VTT-OSGC Platform Enablement
Intel Corporation
(916) 356-2795