drm: Add support for multiple plane types (v2)

The DRM core currently only tracks "overlay"-style planes.  Start
refactoring the plane handling to allow other plane types (primary and
cursor) to also be placed on the DRM plane list.

v2: Add drm_for_each_legacy_plane() iterator to smooth transition
    of drivers with plane loops.

Signed-off-by: Matt Roper <matthew.d.roper@intel.com>
Reviewed-by: Rob Clark <robdclark@gmail.com>

drivers/gpu/drm/drm_crtc.c

@@ -1044,14 +1044,17 @@ int drm_plane_init(struct drm_device *dev, struct drm_plane *plane,
 	memcpy(plane->format_types, formats, format_count * sizeof(uint32_t));
 	plane->format_count = format_count;
 	plane->possible_crtcs = possible_crtcs;
+	plane->type = DRM_PLANE_TYPE_OVERLAY;
 
 	/* private planes are not exposed to userspace, but depending on
 	 * display hardware, might be convenient to allow sharing programming
 	 * for the scanout engine with the crtc implementation.
 	 */
 	if (!priv) {
 		list_add_tail(&plane->head, &dev->mode_config.plane_list);
-		dev->mode_config.num_plane++;
+		dev->mode_config.num_total_plane++;
+		if (plane->type == DRM_PLANE_TYPE_OVERLAY)
+			dev->mode_config.num_overlay_plane++;
 	} else {
 		INIT_LIST_HEAD(&plane->head);
 	}
@@ -1081,7 +1084,9 @@ void drm_plane_cleanup(struct drm_plane *plane)
 	/* if not added to a list, it must be a private plane */
 	if (!list_empty(&plane->head)) {
 		list_del(&plane->head);
-		dev->mode_config.num_plane--;
+	        dev->mode_config.num_total_plane--;
+		if (plane->type == DRM_PLANE_TYPE_OVERLAY)
+			dev->mode_config.num_overlay_plane--;
 	}
 	drm_modeset_unlock_all(dev);
 }
@@ -1908,19 +1913,23 @@ int drm_mode_getplane_res(struct drm_device *dev, void *data,
 	 * This ioctl is called twice, once to determine how much space is
 	 * needed, and the 2nd time to fill it.
 	 */
-	if (config->num_plane &&
-	    (plane_resp->count_planes >= config->num_plane)) {
+	if (config->num_overlay_plane &&
+	    (plane_resp->count_planes >= config->num_overlay_plane)) {
 		plane_ptr = (uint32_t __user *)(unsigned long)plane_resp->plane_id_ptr;
 
 		list_for_each_entry(plane, &config->plane_list, head) {
+			/* Only advertise overlays to userspace for now. */
+			if (plane->type != DRM_PLANE_TYPE_OVERLAY)
+				continue;
+
 			if (put_user(plane->base.id, plane_ptr + copied)) {
 				ret = -EFAULT;
 				goto out;
 			}
 			copied++;
 		}
 	}
-	plane_resp->count_planes = config->num_plane;
+	plane_resp->count_planes = config->num_overlay_plane;
 
 out:
 	drm_modeset_unlock_all(dev);
@@ -4534,6 +4543,8 @@ void drm_mode_config_init(struct drm_device *dev)
 	dev->mode_config.num_connector = 0;
 	dev->mode_config.num_crtc = 0;
 	dev->mode_config.num_encoder = 0;
+	dev->mode_config.num_overlay_plane = 0;
+	dev->mode_config.num_total_plane = 0;
 }
 EXPORT_SYMBOL(drm_mode_config_init);
 

drivers/gpu/drm/drm_fb_helper.c

@@ -291,7 +291,8 @@ bool drm_fb_helper_restore_fbdev_mode(struct drm_fb_helper *fb_helper)
 	drm_warn_on_modeset_not_all_locked(dev);
 
 	list_for_each_entry(plane, &dev->mode_config.plane_list, head)
-		drm_plane_force_disable(plane);
+		if (plane->type != DRM_PLANE_TYPE_PRIMARY)
+			drm_plane_force_disable(plane);
 
 	for (i = 0; i < fb_helper->crtc_count; i++) {
 		struct drm_mode_set *mode_set = &fb_helper->crtc_info[i].mode_set;

include/drm/drm_crtc.h

@@ -541,6 +541,12 @@ struct drm_plane_funcs {
 			    struct drm_property *property, uint64_t val);
 };
 
+enum drm_plane_type {
+	DRM_PLANE_TYPE_OVERLAY,
+	DRM_PLANE_TYPE_PRIMARY,
+	DRM_PLANE_TYPE_CURSOR,
+};
+
 /**
  * drm_plane - central DRM plane control structure
  * @dev: DRM device this plane belongs to
@@ -553,6 +559,7 @@ struct drm_plane_funcs {
  * @fb: currently bound fb
  * @funcs: helper functions
  * @properties: property tracking for this plane
+ * @type: type of plane (overlay, primary, cursor)
  */
 struct drm_plane {
 	struct drm_device *dev;
@@ -570,6 +577,8 @@ struct drm_plane {
 	const struct drm_plane_funcs *funcs;
 
 	struct drm_object_properties properties;
+
+	enum drm_plane_type type;
 };
 
 /**
@@ -732,7 +741,15 @@ struct drm_mode_config {
 	struct list_head bridge_list;
 	int num_encoder;
 	struct list_head encoder_list;
-	int num_plane;
+
+	/*
+	 * Track # of overlay planes separately from # of total planes.  By
+	 * default we only advertise overlay planes to userspace; if userspace
+	 * sets the "universal plane" capability bit, we'll go ahead and
+	 * expose all planes.
+	 */
+	int num_overlay_plane;
+	int num_total_plane;
 	struct list_head plane_list;
 
 	int num_crtc;
@@ -1036,4 +1053,9 @@ static inline struct drm_encoder *drm_encoder_find(struct drm_device *dev,
 	return mo ? obj_to_encoder(mo) : NULL;
 }
 
+/* Plane list iterator for legacy (overlay only) planes. */
+#define drm_for_each_legacy_plane(plane, planelist) \
+	list_for_each_entry(plane, planelist, head) \
+		if (plane->type == DRM_PLANE_TYPE_OVERLAY)
+
 #endif /* __DRM_CRTC_H__ */