On Thu, 21 Mar 2019, Manasi Navare <[email protected]> wrote:
> In case of tiled displays when the two tiles are sent across two CRTCs
> over two separate DP SST connectors, we need a mechanism to synchronize
> the two CRTCs and their corresponding transcoders.
> So use the master-slave mode where there is one master corresponding
> to last horizontal and vertical tile that needs to be genlocked with
> all other slave tiles.
> This patch identifies saves the master CRTC pointer in all the slave
> CRTC states. This pointer is needed to select the master CRTC/transcoder
> while configuring transcoder port sync for the corresponding slaves.
>
> Cc: Daniel Vetter <[email protected]>
> Cc: Ville Syrjälä <[email protected]>
> Cc: Maarten Lankhorst <[email protected]>
> Cc: Matt Roper <[email protected]>
> Signed-off-by: Manasi Navare <[email protected]>
> ---
>  drivers/gpu/drm/i915/intel_display.c | 84 ++++++++++++++++++++++++++++
>  drivers/gpu/drm/i915/intel_drv.h     |  3 +
>  2 files changed, 87 insertions(+)
>
> diff --git a/drivers/gpu/drm/i915/intel_display.c 
> b/drivers/gpu/drm/i915/intel_display.c
> index 8ff7aa8cb3cf..9980a4ed8c9c 100644
> --- a/drivers/gpu/drm/i915/intel_display.c
> +++ b/drivers/gpu/drm/i915/intel_display.c
> @@ -11281,6 +11281,86 @@ static int icl_check_nv12_planes(struct 
> intel_crtc_state *crtc_state)
>       return 0;
>  }
>  
> +static int icl_add_genlock_crtcs(struct drm_device *dev,
> +                              struct drm_atomic_state *state)
> +{
> +     struct drm_i915_private *dev_priv = to_i915(dev);
> +     struct drm_connector *genlock_connector, *connector;
> +     struct drm_connector_state *connector_state;
> +     struct drm_connector_list_iter conn_iter;
> +     struct drm_crtc *genlock_crtc = NULL;
> +     struct drm_crtc_state *genlock_crtc_state;
> +     struct intel_crtc_state *slave_crtc_state;
> +     int i, tile_group_id;
> +
> +     if (INTEL_GEN(dev_priv) < 11)
> +             return 0;
> +
> +     /*
> +      * In case of tiled displays there could be one or more slaves but 
> there is
> +      * only one master. Lets make the CRTC used by the connector 
> corresponding
> +      * to the last horizonal and last vertical tile a master/genlock CRTC.
> +      * All the other CRTCs corresponding to other tiles of the same Tile 
> group
> +      * are the slave CRTCs and hold a pointer to their genlock CRTC.
> +      */
> +     for_each_new_connector_in_state(state, connector, connector_state, i) {
> +             if (!connector_state->crtc)
> +                     continue;
> +             if (!connector->has_tile)
> +                     continue;
> +             if (connector->tile_h_loc == connector->num_h_tile - 1 &&
> +                 connector->tile_v_loc == connector->num_v_tile - 1)
> +                     continue;
> +             slave_crtc_state = to_intel_crtc_state(
> +                     drm_atomic_get_new_crtc_state(state,
> +                                                   connector_state->crtc));
> +             slave_crtc_state->genlock_crtc = NULL;
> +             tile_group_id = connector->tile_group->id;
> +             drm_connector_list_iter_begin(dev, &conn_iter);
> +             drm_for_each_connector_iter(genlock_connector, &conn_iter) {
> +                     struct drm_connector_state *genlock_conn_state = NULL;
> +
> +                     if (!genlock_connector->has_tile)
> +                             continue;
> +                     if (genlock_connector->tile_h_loc != 
> genlock_connector->num_h_tile - 1 ||
> +                         genlock_connector->tile_v_loc != 
> genlock_connector->num_v_tile - 1)
> +                             continue;
> +                     if (genlock_connector->tile_group->id != tile_group_id)
> +                             continue;
> +
> +                     genlock_conn_state = 
> drm_atomic_get_connector_state(state,
> +                                                                         
> genlock_connector);
> +                     if (IS_ERR(genlock_conn_state)) {
> +                             drm_connector_list_iter_end(&conn_iter);
> +                             return PTR_ERR(genlock_conn_state);
> +                     }
> +                     if (genlock_conn_state->crtc) {
> +                             genlock_crtc = genlock_conn_state->crtc;
> +                             break;
> +                     }
> +             }
> +             drm_connector_list_iter_end(&conn_iter);

The above loop would benefit from being abstracted to a separate
function. "find genlock master based on tile info"

I wonder if it would work to have each relevant encoder ->compute_config
hook look for its genlock master instead of adding another top level
loop.

BR,
Jani.


> +
> +             if (!genlock_crtc) {
> +                     DRM_DEBUG_KMS("Could not add Genlock CRTC for Slave 
> CRTC %d\n",
> +                                   connector_state->crtc->base.id);
> +                     return -EINVAL;
> +             }
> +
> +             genlock_crtc_state = drm_atomic_get_crtc_state(state,
> +                                                            genlock_crtc);
> +             if (IS_ERR(genlock_crtc_state))
> +                     return PTR_ERR(genlock_crtc_state);
> +
> +             slave_crtc_state->genlock_crtc = to_intel_crtc(genlock_crtc);
> +             DRM_DEBUG_KMS("Genlock CRTC = %d added for Slave CRTC = %d\n",
> +                           genlock_crtc->base.id,
> +                           slave_crtc_state->base.crtc->base.id);
> +     }
> +
> +     return 0;
> +}
> +
>  static int intel_crtc_atomic_check(struct drm_crtc *crtc,
>                                  struct drm_crtc_state *crtc_state)
>  {
> @@ -13098,6 +13178,10 @@ static int intel_atomic_check(struct drm_device *dev,
>       if (ret)
>               return ret;
>  
> +     ret = icl_add_genlock_crtcs(dev, state);
> +     if (ret)
> +             return ret;
> +
>       for_each_oldnew_crtc_in_state(state, crtc, old_crtc_state, crtc_state, 
> i) {
>               struct intel_crtc_state *pipe_config =
>                       to_intel_crtc_state(crtc_state);
> diff --git a/drivers/gpu/drm/i915/intel_drv.h 
> b/drivers/gpu/drm/i915/intel_drv.h
> index 4d7ae579fc92..b41728946b73 100644
> --- a/drivers/gpu/drm/i915/intel_drv.h
> +++ b/drivers/gpu/drm/i915/intel_drv.h
> @@ -1074,6 +1074,9 @@ struct intel_crtc_state {
>  
>       /* Forward Error correction State */
>       bool fec_enable;
> +
> +     /* Pointer to master/genlock crtc in case of tiled displays */
> +     struct intel_crtc *genlock_crtc;
>  };
>  
>  struct intel_crtc {

-- 
Jani Nikula, Intel Open Source Graphics Center
_______________________________________________
Intel-gfx mailing list
[email protected]
https://lists.freedesktop.org/mailman/listinfo/intel-gfx

Reply via email to