diff options
Diffstat (limited to 'drivers/gpu')
| -rw-r--r-- | drivers/gpu/drm/drm_blend.c | 146 | ||||
| -rw-r--r-- | drivers/gpu/drm/drm_plane.c | 3 |
2 files changed, 131 insertions, 18 deletions
diff --git a/drivers/gpu/drm/drm_blend.c b/drivers/gpu/drm/drm_blend.c index 0b8e227aa175..85172a977bf3 100644 --- a/drivers/gpu/drm/drm_blend.c +++ b/drivers/gpu/drm/drm_blend.c @@ -32,6 +32,118 @@ #include "drm_crtc_internal.h" +/** + * DOC: overview + * + * The basic plane composition model supported by standard plane properties only + * has a source rectangle (in logical pixels within the &drm_framebuffer), with + * sub-pixel accuracy, which is scaled up to a pixel-aligned destination + * rectangle in the visible area of a &drm_crtc. The visible area of a CRTC is + * defined by the horizontal and vertical visible pixels (stored in @hdisplay + * and @vdisplay) of the requested mode (stored in @mode in the + * &drm_crtc_state). These two rectangles are both stored in the + * &drm_plane_state. + * + * For the atomic ioctl the following standard (atomic) properties on the plane object + * encode the basic plane composition model: + * + * SRC_X: + * X coordinate offset for the source rectangle within the + * &drm_framebuffer, in 16.16 fixed point. Must be positive. + * SRC_Y: + * Y coordinate offset for the source rectangle within the + * &drm_framebuffer, in 16.16 fixed point. Must be positive. + * SRC_W: + * Width for the source rectangle within the &drm_framebuffer, in 16.16 + * fixed point. SRC_X plus SRC_W must be within the width of the source + * framebuffer. Must be positive. + * SRC_H: + * Height for the source rectangle within the &drm_framebuffer, in 16.16 + * fixed point. SRC_Y plus SRC_H must be within the height of the source + * framebuffer. Must be positive. + * CRTC_X: + * X coordinate offset for the destination rectangle. Can be negative. + * CRTC_Y: + * Y coordinate offset for the destination rectangle. Can be negative. + * CRTC_W: + * Width for the destination rectangle. CRTC_X plus CRTC_W can extend past + * the currently visible horizontal area of the &drm_crtc. + * CRTC_H: + * Height for the destination rectangle. CRTC_Y plus CRTC_H can extend past + * the currently visible vertical area of the &drm_crtc. + * FB_ID: + * Mode object ID of the &drm_framebuffer this plane should scan out. + * CRTC_ID: + * Mode object ID of the &drm_crtc this plane should be connected to. + * + * Note that the source rectangle must fully lie within the bounds of the + * &drm_framebuffer. The destination rectangle can lie outside of the visible + * area of the current mode of the CRTC. It must be apprpriately clipped by the + * driver, which can be done by calling drm_plane_helper_check_update(). Drivers + * are also allowed to round the subpixel sampling positions appropriately, but + * only to the next full pixel. No pixel outside of the source rectangle may + * ever be sampled, which is important when applying more sophisticated + * filtering than just a bilinear one when scaling. The filtering mode when + * scaling is unspecified. + * + * On top of this basic transformation additional properties can be exposed by + * the driver: + * + * - Rotation is set up with drm_mode_create_rotation_property(). It adds a + * rotation and reflection step between the source and destination rectangles. + * Without this property the rectangle is only scaled, but not rotated or + * reflected. + * + * - Z position is set up with drm_plane_create_zpos_immutable_property() and + * drm_plane_create_zpos_property(). It controls the visibility of overlapping + * planes. Without this property the primary plane is always below the cursor + * plane, and ordering between all other planes is undefined. + * + * Note that all the property extensions described here apply either to the + * plane or the CRTC (e.g. for the background color, which currently is not + * exposed and assumed to be black). + */ + +/** + * drm_mode_create_rotation_property - create a new rotation property + * @dev: DRM device + * @supported_rotations: bitmask of supported rotations and reflections + * + * This creates a new property with the selected support for transformations. + * The resulting property should be stored in @rotation_property in + * &drm_mode_config. It then must be attached to each plane which supports + * rotations using drm_object_attach_property(). + * + * FIXME: Probably better if the rotation property is created on each plane, + * like the zpos property. Otherwise it's not possible to allow different + * rotation modes on different planes. + * + * Since a rotation by 180° degress is the same as reflecting both along the x + * and the y axis the rotation property is somewhat redundant. Drivers can use + * drm_rotation_simplify() to normalize values of this property. + * + * The property exposed to userspace is a bitmask property (see + * drm_property_create_bitmask()) called "rotation" and has the following + * bitmask enumaration values: + * + * DRM_ROTATE_0: + * "rotate-0" + * DRM_ROTATE_90: + * "rotate-90" + * DRM_ROTATE_180: + * "rotate-180" + * DRM_ROTATE_270: + * "rotate-270" + * DRM_REFLECT_X: + * "reflect-x" + * DRM_REFELCT_Y: + * "reflect-y" + * + * Rotation is the specified amount in degrees in counter clockwise direction, + * the X and Y axis are within the source rectangle, i.e. the X/Y axis before + * rotation. After reflection, the rotation is applied to the image sampled from + * the source rectangle, before scaling it to fit the destination rectangle. + */ struct drm_property *drm_mode_create_rotation_property(struct drm_device *dev, unsigned int supported_rotations) { @@ -98,10 +210,14 @@ EXPORT_SYMBOL(drm_rotation_simplify); * If zpos of some planes cannot be changed (like fixed background or * cursor/topmost planes), driver should adjust min/max values and assign those * planes immutable zpos property with lower or higher values (for more - * information, see drm_mode_create_zpos_immutable_property() function). In such + * information, see drm_plane_create_zpos_immutable_property() function). In such * case driver should also assign proper initial zpos values for all planes in * its plane_reset() callback, so the planes will be always sorted properly. * + * See also drm_atomic_normalize_zpos(). + * + * The property exposed to userspace is called "zpos". + * * Returns: * Zero on success, negative errno on failure. */ @@ -137,7 +253,9 @@ EXPORT_SYMBOL(drm_plane_create_zpos_property); * support for it in drm core. Using this property driver lets userspace * to get the arrangement of the planes for blending operation and notifies * it that the hardware (or driver) doesn't support changing of the planes' - * order. + * order. For mutable zpos see drm_plane_create_zpos_property(). + * + * The property exposed to userspace is called "zpos". * * Returns: * Zero on success, negative errno on failure. @@ -176,20 +294,6 @@ static int drm_atomic_state_zpos_cmp(const void *a, const void *b) return sa->plane->base.id - sb->plane->base.id; } -/** - * drm_atomic_helper_crtc_normalize_zpos - calculate normalized zpos values - * @crtc: crtc with planes, which have to be considered for normalization - * @crtc_state: new atomic state to apply - * - * This function checks new states of all planes assigned to given crtc and - * calculates normalized zpos value for them. Planes are compared first by their - * zpos values, then by plane id (if zpos equals). Plane with lowest zpos value - * is at the bottom. The plane_state->normalized_zpos is then filled with unique - * values from 0 to number of active planes in crtc minus one. - * - * RETURNS - * Zero for success or -errno - */ static int drm_atomic_helper_crtc_normalize_zpos(struct drm_crtc *crtc, struct drm_crtc_state *crtc_state) { @@ -247,8 +351,14 @@ done: * @state: atomic state of DRM device * * This function calculates normalized zpos value for all modified planes in - * the provided atomic state of DRM device. For more information, see - * drm_atomic_helper_crtc_normalize_zpos() function. + * the provided atomic state of DRM device. + * + * For every CRTC this function checks new states of all planes assigned to + * it and calculates normalized zpos value for these planes. Planes are compared + * first by their zpos values, then by plane id (if zpos is equal). The plane + * with lowest zpos value is at the bottom. The plane_state->normalized_zpos is + * then filled with unique values from 0 to number of active planes in crtc + * minus one. * * RETURNS * Zero for success or -errno diff --git a/drivers/gpu/drm/drm_plane.c b/drivers/gpu/drm/drm_plane.c index c17c9c2a342e..cd0d475bf3c3 100644 --- a/drivers/gpu/drm/drm_plane.c +++ b/drivers/gpu/drm/drm_plane.c @@ -45,6 +45,9 @@ * &drm_plane_type for a more in-depth discussion of these special uapi-relevant * plane types. Special planes are associated with their CRTC by calling * drm_crtc_init_with_planes(). + * + * The type of a plane is exposed in the immutable "type" enumeration property, + * which has one of the following values: "Overlay", "Primary", "Cursor". */ static unsigned int drm_num_planes(struct drm_device *dev) |