diff --git a/drivers/gpu/drm/drm_mode_config.c b/drivers/gpu/drm/drm_mode_config.c index 48fd2d67f352f4ed3788ecb69d0e6249bde8b702..568972258222af09207b15eafe4d65ad96406fdd 100644 --- a/drivers/gpu/drm/drm_mode_config.c +++ b/drivers/gpu/drm/drm_mode_config.c @@ -372,6 +372,13 @@ static int drm_mode_create_standard_properties(struct drm_device *dev) return -ENOMEM; dev->mode_config.modifiers_property = prop; + prop = drm_property_create(dev, + DRM_MODE_PROP_IMMUTABLE | DRM_MODE_PROP_BLOB, + "SIZE_HINTS", 0); + if (!prop) + return -ENOMEM; + dev->mode_config.size_hints_property = prop; + return 0; } diff --git a/drivers/gpu/drm/drm_plane.c b/drivers/gpu/drm/drm_plane.c index 672c655c7a8e7e4bea908ddcb5d74fc7c1549674..eecc24c54efdf2abef330769f524b8dbf98bb06b 100644 --- a/drivers/gpu/drm/drm_plane.c +++ b/drivers/gpu/drm/drm_plane.c @@ -140,6 +140,25 @@ * DRM_FORMAT_MOD_LINEAR. Before linux kernel release v5.1 there have been * various bugs in this area with inconsistencies between the capability * flag and per-plane properties. + * + * SIZE_HINTS: + * Blob property which contains the set of recommended plane size + * which can used for simple "cursor like" use cases (eg. no scaling). + * Using these hints frees userspace from extensive probing of + * supported plane sizes through atomic/setcursor ioctls. + * + * The blob contains an array of struct drm_plane_size_hint, in + * order of preference. For optimal usage userspace should pick + * the first size that satisfies its own requirements. + * + * Drivers should only attach this property to planes that + * support a very limited set of sizes. + * + * Note that property value 0 (ie. no blob) is reserved for potential + * future use. Current userspace is expected to ignore the property + * if the value is 0, and fall back to some other means (eg. + * &DRM_CAP_CURSOR_WIDTH and &DRM_CAP_CURSOR_HEIGHT) to determine + * the appropriate plane size to use. */ static unsigned int drm_num_planes(struct drm_device *dev) @@ -1729,3 +1748,40 @@ int drm_plane_create_scaling_filter_property(struct drm_plane *plane, return 0; } EXPORT_SYMBOL(drm_plane_create_scaling_filter_property); + +/** + * drm_plane_add_size_hint_property - create a size hint property + * + * @plane: drm plane + * @hints: size hints + * @num_hints: number of size hints + * + * Create a size hints property for the plane. + * + * RETURNS: + * Zero for success or -errno + */ +int drm_plane_add_size_hints_property(struct drm_plane *plane, + const struct drm_plane_size_hint *hints, + int num_hints) +{ + struct drm_device *dev = plane->dev; + struct drm_mode_config *config = &dev->mode_config; + struct drm_property_blob *blob; + + /* extending to other plane types needs actual thought */ + if (drm_WARN_ON(dev, plane->type != DRM_PLANE_TYPE_CURSOR)) + return -EINVAL; + + blob = drm_property_create_blob(dev, + array_size(sizeof(hints[0]), num_hints), + hints); + if (IS_ERR(blob)) + return PTR_ERR(blob); + + drm_object_attach_property(&plane->base, config->size_hints_property, + blob->base.id); + + return 0; +} +EXPORT_SYMBOL(drm_plane_add_size_hints_property); diff --git a/include/drm/drm_mode_config.h b/include/drm/drm_mode_config.h index 973119a9176b26eb5f1a72ef55bbbbc24293521a..9d8acf7a10eb8f56ee9d70cafadf9d232a854efa 100644 --- a/include/drm/drm_mode_config.h +++ b/include/drm/drm_mode_config.h @@ -942,6 +942,11 @@ struct drm_mode_config { */ struct drm_property *modifiers_property; + /** + * @size_hints_propertty: Plane SIZE_HINTS property. + */ + struct drm_property *size_hints_property; + /* cursor size */ uint32_t cursor_width, cursor_height; diff --git a/include/drm/drm_plane.h b/include/drm/drm_plane.h index 641fe298052dc3cc1a9b779a09cbbb314a0b8309..ec1112208b735e60af7d0712f6c9c9f7763d7ac7 100644 --- a/include/drm/drm_plane.h +++ b/include/drm/drm_plane.h @@ -32,6 +32,7 @@ #include <drm/drm_util.h> struct drm_crtc; +struct drm_plane_size_hint; struct drm_printer; struct drm_modeset_acquire_ctx; @@ -976,5 +977,8 @@ drm_plane_get_damage_clips(const struct drm_plane_state *state); int drm_plane_create_scaling_filter_property(struct drm_plane *plane, unsigned int supported_filters); +int drm_plane_add_size_hints_property(struct drm_plane *plane, + const struct drm_plane_size_hint *hints, + int num_hints); #endif diff --git a/include/uapi/drm/drm_mode.h b/include/uapi/drm/drm_mode.h index 7040e7ea80c79d61c4ce02534b0150eb4e4c8a8b..1ca5c7e418fd2bbff473ee612ccc9f38ed2650ce 100644 --- a/include/uapi/drm/drm_mode.h +++ b/include/uapi/drm/drm_mode.h @@ -865,6 +865,17 @@ struct drm_color_lut { __u16 reserved; }; +/** + * struct drm_plane_size_hint - Plane size hints + * + * The plane SIZE_HINTS property blob contains an + * array of struct drm_plane_size_hint. + */ +struct drm_plane_size_hint { + __u16 width; + __u16 height; +}; + /** * struct hdr_metadata_infoframe - HDR Metadata Infoframe Data. *