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

[Manasi Navare]

On Fri, Dec 13, 2019 at 10:05:49PM +0200, Ville Syrjälä wrote:
> On Wed, Dec 11, 2019 at 01:14:23PM -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.
> > 
> > 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>
> > 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 | 78 ++++++++++++++++++++
> >  1 file changed, 78 insertions(+)
> > 
> > diff --git a/drivers/gpu/drm/i915/display/intel_display.c b/drivers/gpu/drm/i915/display/intel_display.c
> > index 803993a01ca7..7263eaa66cda 100644
> > --- a/drivers/gpu/drm/i915/display/intel_display.c
> > +++ b/drivers/gpu/drm/i915/display/intel_display.c
> > @@ -14066,6 +14066,80 @@ static int intel_atomic_check_crtcs(struct intel_atomic_state *state)
> >  	return 0;
> >  }
> >  
> > +static int
> > +intel_dp_modeset_all_tiles(struct drm_i915_private *dev_priv,
> > +			   struct intel_atomic_state *state, int tile_grp_id)
> > +{
> > +	struct drm_connector *conn_iter;
> 'connector'
> > +	struct drm_connector_list_iter conn_list_iter;
> > +	struct drm_crtc_state *crtc_state;
> 
> crtc_state has needlessly wide scope.
> 
> > +
> > +	drm_connector_list_iter_begin(&dev_priv->drm, &conn_list_iter);
> > +	drm_for_each_connector_iter(conn_iter, &conn_list_iter) {
> > +		struct drm_connector_state *conn_iter_state;
> 
> 'conn_state' is the most popular name.
> 
> > +
> > +		if (!conn_iter->has_tile)
> > +			continue;
> > +		conn_iter_state = drm_atomic_get_connector_state(&state->base,
> > +								 conn_iter);
> > +		if (IS_ERR(conn_iter_state)) {
> > +			drm_connector_list_iter_end(&conn_list_iter);
> > +			return PTR_ERR(conn_iter_state);
> > +		}
> > +
> > +		if (!conn_iter_state->crtc)
> > +			continue;
> > +
> > +		if (conn_iter->tile_group->id != tile_grp_id)
> > +			continue;
> 
> The tile group check should be part of the same if with the has_tile
> check.
> 
> > +
> > +		crtc_state = drm_atomic_get_crtc_state(&state->base, conn_iter_state->crtc);
> > +		if (IS_ERR(crtc_state)) {
> > +			drm_connector_list_iter_end(&conn_list_iter);
> > +			return PTR_ERR(conn_iter_state);
> > +		}
> > +		crtc_state->mode_changed = true;
> > +	}
> > +	drm_connector_list_iter_end(&conn_list_iter);
> > +
> > +	return 0;
> > +}
> > +
> > +static int
> > +intel_dp_atomic_trans_port_sync_check(struct drm_i915_private *dev_priv,
> 
> Pointless variable. Can be extracted from the atomic state.
> 
> > +				      struct intel_atomic_state *state)
> > +{
> > +	struct drm_connector *connector;
> > +	struct drm_crtc_state *crtc_state;
> > +	struct drm_connector_state *connector_state;
> > +	int i, ret, tile_grp_id = 0;
> 
> tile_grp_id is rather pointless. crtc_state and ret can move into
> tighter scope. And the next suggestion allows you to kill crtc_state
> entirely...

Its not clear why tile_grp_id is pointless, I am using tile_grp_id for the first connector with has_tile
and I make sure that I dont enter into the loop to check modeset again for the connector with
same tile_grp_id because we have already set its mode changed to true in intel_dp_modeset_all_tiles()

How can I achieve this instead?

Manasi

> 
> > +
> > +	if (INTEL_GEN(dev_priv) < 11)
> > +		return 0;
> > +
> > +	/* Is tiled, mark all other tiled CRTCs as needing a modeset */
> > +	for_each_new_connector_in_state(&state->base, connector, connector_state, i) {
> > +		if (!connector->has_tile)
> > +			continue;
> > +		if (connector_state->crtc &&
> > +		    tile_grp_id != connector->tile_group->id) {
> > +			crtc_state = drm_atomic_get_new_crtc_state(&state->base,
> > +								   connector_state->crtc);
> > +			if (!drm_atomic_crtc_needs_modeset(crtc_state))
> > +				continue;
> 
> This should to be able to be shortened to just intel_connector_needs_modeset().
> 
> > +
> > +			tile_grp_id = connector->tile_group->id;
> > +		} else
> > +			continue;
> > +
> > +		ret = intel_dp_modeset_all_tiles(dev_priv, state, tile_grp_id);
> > +		if (ret)
> > +			return ret;
> > +	}
> > +
> > +	return 0;
> > +}
> > +
> >  /**
> >   * intel_atomic_check - validate state object
> >   * @dev: drm device
> > @@ -14093,6 +14167,10 @@ static int intel_atomic_check(struct drm_device *dev,
> >  	if (ret)
> >  		goto fail;
> >  
> > +	ret = intel_dp_atomic_trans_port_sync_check(dev_priv, state);
> > +	if (ret)
> > +		goto fail;
> 
> We should probably do this from the connector .atomic_check() hook if
> Jose is going to do the MST thing that way. But no real problem doing
> here I think.
> 
> > +
> >  	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
> 
> -- 
> Ville Syrjälä
> Intel