drm: add generic zpos property

version 8:
- move drm_blend.o from drm-y to drm_kms_helper-y to avoid
  EXPORT_SYMBOL(drm_atomic_helper_normalize_zpos)
- remove dead function declarations in drm_crtc.h

version 7:
- remove useless EXPORT_SYMBOL()
- better z-order wording in Documentation

version 6:
- add zpos in gpu documentation file
- merge Ville patch about zpos initial value and API improvement.
  I have split Ville patch between zpos core and drivers

version 5:
- remove zpos range check and comeback to 0 to N-1
  normalization algorithm

version 4:
- make sure that normalized zpos value is stay
  in the defined property range and warn user if not

This patch adds support for generic plane's zpos property property with
well-defined semantics:
- added zpos properties to plane and plane state structures
- added helpers for normalizing zpos properties of given set of planes
- well defined semantics: planes are sorted by zpos values and then plane
  id value if zpos equals

Normalized zpos values are calculated automatically when generic
muttable zpos property has been initialized. Drivers can simply use
plane_state->normalized_zpos in their atomic_check and/or plane_update
callbacks without any additional calls to DRM core.

Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>

Compare to Marek's original patch zpos property is now specific to each
plane and no more to the core.
Normalize function take care of the range of per plane defined range
before set normalized_zpos.

Signed-off-by: Benjamin Gaignard <benjamin.gaignard@linaro.org>
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Tested-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>

Cc: Inki Dae <inki.dae@samsung.com>
Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: Ville Syrjala <ville.syrjala@linux.intel.com>
Cc: Joonyoung Shim <jy0922.shim@samsung.com>
Cc: Seung-Woo Kim <sw0312.kim@samsung.com>
Cc: Andrzej Hajda <a.hajda@samsung.com>
Cc: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Cc: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Cc: Tobias Jakobi <tjakobi@math.uni-bielefeld.de>
Cc: Gustavo Padovan <gustavo@padovan.org>
Cc: vincent.abriou@st.com
Cc: fabien.dessenne@st.com
Cc: Laurent Pinchart <laurent.pinchart@ideasonboard.com>

1 files changed, 20 insertions, 0 deletions

diff --git a/include/drm/drm_crtc.h b/include/drm/drm_crtc.h
index 3edeaf88ebc0..44e070800b6d 100644
--- a/include/drm/drm_crtc.h
+++ b/include/drm/drm_crtc.h
@@ -308,6 +308,7 @@ struct drm_plane_helper_funcs;
  * @mode_changed: crtc_state->mode or crtc_state->enable has been changed
  * @active_changed: crtc_state->active has been toggled.
  * @connectors_changed: connectors to this crtc have been updated
+ * @zpos_changed: zpos values of planes on this crtc have been updated
  * @color_mgmt_changed: color management properties have changed (degamma or
  *      gamma LUT or CSC matrix)
  * @plane_mask: bitmask of (1 << drm_plane_index(plane)) of attached planes
@@ -344,6 +345,7 @@ struct drm_crtc_state {
         bool mode_changed : 1;
         bool active_changed : 1;
         bool connectors_changed : 1;
+        bool zpos_changed : 1;
         bool color_mgmt_changed : 1;
 
         /* attached planes bitmask:
@@ -1409,6 +1411,9 @@ struct drm_connector {
  * @src_w: width of visible portion of plane (in 16.16)
  * @src_h: height of visible portion of plane (in 16.16)
  * @rotation: rotation of the plane
+ * @zpos: priority of the given plane on crtc (optional)
+ * @normalized_zpos: normalized value of zpos: unique, range from 0 to N-1
+ *      where N is the number of active planes for given crtc
  * @state: backpointer to global drm_atomic_state
  */
 struct drm_plane_state {
@@ -1429,6 +1434,10 @@ struct drm_plane_state {
         /* Plane rotation */
         unsigned int rotation;
 
+        /* Plane zpos */
+        unsigned int zpos;
+        unsigned int normalized_zpos;
+
         struct drm_atomic_state *state;
 };
 
@@ -1688,6 +1697,7 @@ enum drm_plane_type {
  * @properties: property tracking for this plane
  * @type: type of plane (overlay, primary, cursor)
  * @state: current atomic state for this plane
+ * @zpos_property: zpos property for this plane
  * @helper_private: mid-layer private data
  */
 struct drm_plane {
@@ -1732,6 +1742,8 @@ struct drm_plane {
         const struct drm_plane_helper_funcs *helper_private;
 
         struct drm_plane_state *state;
+
+        struct drm_property *zpos_property;
 };
 
 /**
@@ -2958,6 +2970,14 @@ extern void drm_crtc_enable_color_mgmt(struct drm_crtc *crtc,
                                        uint degamma_lut_size,
                                        bool has_ctm,
                                        uint gamma_lut_size);
+
+int drm_plane_create_zpos_property(struct drm_plane *plane,
+                                   unsigned int zpos,
+                                   unsigned int min, unsigned int max);
+
+int drm_plane_create_zpos_immutable_property(struct drm_plane *plane,
+                                             unsigned int zpos);
+
 /* Helpers */
 struct drm_mode_object *drm_mode_object_find(struct drm_device *dev,
                                              uint32_t id, uint32_t type);