/* * Copyright (C) 2016 Samsung Electronics Co.Ltd * Authors: * Marek Szyprowski <[email protected]> * * DRM core plane blending related functions * * Permission to use, copy, modify, distribute, and sell this software and its * documentation for any purpose is hereby granted without fee, provided that * the above copyright notice appear in all copies and that both that copyright * notice and this permission notice appear in supporting documentation, and * that the name of the copyright holders not be used in advertising or * publicity pertaining to distribution of the software without specific, * written prior permission. The copyright holders make no representations * about the suitability of this software for any purpose. It is provided "as * is" without express or implied warranty. * * THE COPYRIGHT HOLDERS DISCLAIM ALL WARRANTIES WITH REGARD TO THIS SOFTWARE, * INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO * EVENT SHALL THE COPYRIGHT HOLDERS BE LIABLE FOR ANY SPECIAL, INDIRECT OR * CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, * DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER * TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE * OF THIS SOFTWARE. */ #include <linux/export.h> #include <linux/slab.h> #include <linux/sort.h> #include <drm/drm_atomic.h> #include <drm/drm_blend.h> #include <drm/drm_device.h> #include <drm/drm_print.h> #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 &drm_crtc_state.mode). 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 appropriately 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: * * alpha: * Alpha is setup with drm_plane_create_alpha_property(). It controls the * plane-wide opacity, from transparent (0) to opaque (0xffff). It can be * combined with pixel alpha. * The pixel values in the framebuffers are expected to not be * pre-multiplied by the global alpha associated to the plane. * * rotation: * Rotation is set up with drm_plane_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. * * Possbile values: * * "rotate-<degrees>": * Signals that a drm plane is rotated <degrees> degrees in counter * clockwise direction. * * "reflect-<axis>": * Signals that the contents of a drm plane is reflected along the * <axis> axis, in the same way as mirroring. * * reflect-x:: * * |o | | o| * | | -> | | * | v| |v | * * reflect-y:: * * |o | | ^| * | | -> | | * | v| |o | * * zpos: * 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. The positive * Z axis points towards the user, i.e. planes with lower Z position values * are underneath planes with higher Z position values. Two planes with the * same Z position value have undefined ordering. Note that the Z position * value can also be immutable, to inform userspace about the hard-coded * stacking of planes, see drm_plane_create_zpos_immutable_property(). If * any plane has a zpos property (either mutable or immutable), then all * planes shall have a zpos property. * * pixel blend mode: * Pixel blend mode is set up with drm_plane_create_blend_mode_property(). * It adds a blend mode for alpha blending equation selection, describing * how the pixels from the current plane are composited with the * background. * * Three alpha blending equations are defined: * * "None": * Blend formula that ignores the pixel alpha:: * * out.rgb = plane_alpha * fg.rgb + * (1 - plane_alpha) * bg.rgb * * "Pre-multiplied": * Blend formula that assumes the pixel color values * have been already pre-multiplied with the alpha * channel values:: * * out.rgb = plane_alpha * fg.rgb + * (1 - (plane_alpha * fg.alpha)) * bg.rgb * * "Coverage": * Blend formula that assumes the pixel color values have not * been pre-multiplied and will do so when blending them to the * background color values:: * * out.rgb = plane_alpha * fg.alpha * fg.rgb + * (1 - (plane_alpha * fg.alpha)) * bg.rgb * * Using the following symbols: * * "fg.rgb": * Each of the RGB component values from the plane's pixel * "fg.alpha": * Alpha component value from the plane's pixel. If the plane's * pixel format has no alpha component, then this is assumed to be * 1.0. In these cases, this property has no effect, as all three * equations become equivalent. * "bg.rgb": * Each of the RGB component values from the background * "plane_alpha": * Plane alpha value set by the plane "alpha" property. If the * plane does not expose the "alpha" property, then this is * assumed to be 1.0 * * 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). * * SCALING_FILTER: * Indicates scaling filter to be used for plane scaler * * The value of this property can be one of the following: * * Default: * Driver's default scaling filter * Nearest Neighbor: * Nearest Neighbor scaling filter * * Drivers can set up this property for a plane by calling * drm_plane_create_scaling_filter_property */ /** * drm_plane_create_alpha_property - create a new alpha property * @plane: drm plane * * This function creates a generic, mutable, alpha property and enables support * for it in the DRM core. It is attached to @plane. * * The alpha property will be allowed to be within the bounds of 0 * (transparent) to 0xffff (opaque). * * Returns: * 0 on success, negative error code on failure. */ int drm_plane_create_alpha_property(struct drm_plane *plane) { … } EXPORT_SYMBOL(…); /** * drm_plane_create_rotation_property - create a new rotation property * @plane: drm plane * @rotation: initial value of the rotation property * @supported_rotations: bitmask of supported rotations and reflections * * This creates a new property with the selected support for transformations. * * 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_MODE_ROTATE_0: * "rotate-0" * DRM_MODE_ROTATE_90: * "rotate-90" * DRM_MODE_ROTATE_180: * "rotate-180" * DRM_MODE_ROTATE_270: * "rotate-270" * DRM_MODE_REFLECT_X: * "reflect-x" * DRM_MODE_REFLECT_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. */ int drm_plane_create_rotation_property(struct drm_plane *plane, unsigned int rotation, unsigned int supported_rotations) { … } EXPORT_SYMBOL(…); /** * drm_rotation_simplify() - Try to simplify the rotation * @rotation: Rotation to be simplified * @supported_rotations: Supported rotations * * Attempt to simplify the rotation to a form that is supported. * Eg. if the hardware supports everything except DRM_MODE_REFLECT_X * one could call this function like this: * * drm_rotation_simplify(rotation, DRM_MODE_ROTATE_0 | * DRM_MODE_ROTATE_90 | DRM_MODE_ROTATE_180 | * DRM_MODE_ROTATE_270 | DRM_MODE_REFLECT_Y); * * to eliminate the DRM_MODE_REFLECT_X flag. Depending on what kind of * transforms the hardware supports, this function may not * be able to produce a supported transform, so the caller should * check the result afterwards. */ unsigned int drm_rotation_simplify(unsigned int rotation, unsigned int supported_rotations) { … } EXPORT_SYMBOL(…); /** * drm_plane_create_zpos_property - create mutable zpos property * @plane: drm plane * @zpos: initial value of zpos property * @min: minimal possible value of zpos property * @max: maximal possible value of zpos property * * This function initializes generic mutable zpos property and enables support * for it in drm core. Drivers can then attach this property to planes to enable * support for configurable planes arrangement during blending operation. * Drivers that attach a mutable zpos property to any plane should call the * drm_atomic_normalize_zpos() helper during their implementation of * &drm_mode_config_funcs.atomic_check(), which will update the normalized zpos * values and store them in &drm_plane_state.normalized_zpos. Usually min * should be set to 0 and max to maximal number of planes for given crtc - 1. * * If zpos of some planes cannot be changed (like fixed background or * cursor/topmost planes), drivers shall adjust the min/max values and assign * those planes immutable zpos properties with lower or higher values (for more * information, see drm_plane_create_zpos_immutable_property() function). In such * case drivers shall 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. */ int drm_plane_create_zpos_property(struct drm_plane *plane, unsigned int zpos, unsigned int min, unsigned int max) { … } EXPORT_SYMBOL(…); /** * drm_plane_create_zpos_immutable_property - create immuttable zpos property * @plane: drm plane * @zpos: value of zpos property * * This function initializes generic immutable zpos property and enables * 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. 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. */ int drm_plane_create_zpos_immutable_property(struct drm_plane *plane, unsigned int zpos) { … } EXPORT_SYMBOL(…); static int drm_atomic_state_zpos_cmp(const void *a, const void *b) { … } static int drm_atomic_helper_crtc_normalize_zpos(struct drm_crtc *crtc, struct drm_crtc_state *crtc_state) { … } /** * drm_atomic_normalize_zpos - calculate normalized zpos values for all crtcs * @dev: DRM device * @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 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 &drm_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 */ int drm_atomic_normalize_zpos(struct drm_device *dev, struct drm_atomic_state *state) { … } EXPORT_SYMBOL(…); /** * drm_plane_create_blend_mode_property - create a new blend mode property * @plane: drm plane * @supported_modes: bitmask of supported modes, must include * BIT(DRM_MODE_BLEND_PREMULTI). Current DRM assumption is * that alpha is premultiplied, and old userspace can break if * the property defaults to anything else. * * This creates a new property describing the blend mode. * * The property exposed to userspace is an enumeration property (see * drm_property_create_enum()) called "pixel blend mode" and has the * following enumeration values: * * "None": * Blend formula that ignores the pixel alpha. * * "Pre-multiplied": * Blend formula that assumes the pixel color values have been already * pre-multiplied with the alpha channel values. * * "Coverage": * Blend formula that assumes the pixel color values have not been * pre-multiplied and will do so when blending them to the background color * values. * * RETURNS: * Zero for success or -errno */ int drm_plane_create_blend_mode_property(struct drm_plane *plane, unsigned int supported_modes) { … } EXPORT_SYMBOL(…);
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