xref: /dragonfly/sys/dev/drm/drm_blend.c (revision 0de61e28)
1 /*
2  * Copyright (C) 2016 Samsung Electronics Co.Ltd
3  * Authors:
4  *	Marek Szyprowski <m.szyprowski@samsung.com>
5  *
6  * DRM core plane blending related functions
7  *
8  * Permission to use, copy, modify, distribute, and sell this software and its
9  * documentation for any purpose is hereby granted without fee, provided that
10  * the above copyright notice appear in all copies and that both that copyright
11  * notice and this permission notice appear in supporting documentation, and
12  * that the name of the copyright holders not be used in advertising or
13  * publicity pertaining to distribution of the software without specific,
14  * written prior permission.  The copyright holders make no representations
15  * about the suitability of this software for any purpose.  It is provided "as
16  * is" without express or implied warranty.
17  *
18  * THE COPYRIGHT HOLDERS DISCLAIM ALL WARRANTIES WITH REGARD TO THIS SOFTWARE,
19  * INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO
20  * EVENT SHALL THE COPYRIGHT HOLDERS BE LIABLE FOR ANY SPECIAL, INDIRECT OR
21  * CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE,
22  * DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER
23  * TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE
24  * OF THIS SOFTWARE.
25  */
26 #include <drm/drmP.h>
27 #include <drm/drm_atomic.h>
28 #include <drm/drm_blend.h>
29 #include <linux/export.h>
30 #include <linux/slab.h>
31 #include <linux/sort.h>
32 
33 #include "drm_crtc_internal.h"
34 
35 /**
36  * DOC: overview
37  *
38  * The basic plane composition model supported by standard plane properties only
39  * has a source rectangle (in logical pixels within the &drm_framebuffer), with
40  * sub-pixel accuracy, which is scaled up to a pixel-aligned destination
41  * rectangle in the visible area of a &drm_crtc. The visible area of a CRTC is
42  * defined by the horizontal and vertical visible pixels (stored in @hdisplay
43  * and @vdisplay) of the requested mode (stored in @mode in the
44  * &drm_crtc_state). These two rectangles are both stored in the
45  * &drm_plane_state.
46  *
47  * For the atomic ioctl the following standard (atomic) properties on the plane object
48  * encode the basic plane composition model:
49  *
50  * SRC_X:
51  * 	X coordinate offset for the source rectangle within the
52  * 	&drm_framebuffer, in 16.16 fixed point. Must be positive.
53  * SRC_Y:
54  * 	Y coordinate offset for the source rectangle within the
55  * 	&drm_framebuffer, in 16.16 fixed point. Must be positive.
56  * SRC_W:
57  * 	Width for the source rectangle within the &drm_framebuffer, in 16.16
58  * 	fixed point. SRC_X plus SRC_W must be within the width of the source
59  * 	framebuffer. Must be positive.
60  * SRC_H:
61  * 	Height for the source rectangle within the &drm_framebuffer, in 16.16
62  * 	fixed point. SRC_Y plus SRC_H must be within the height of the source
63  * 	framebuffer. Must be positive.
64  * CRTC_X:
65  * 	X coordinate offset for the destination rectangle. Can be negative.
66  * CRTC_Y:
67  * 	Y coordinate offset for the destination rectangle. Can be negative.
68  * CRTC_W:
69  * 	Width for the destination rectangle. CRTC_X plus CRTC_W can extend past
70  * 	the currently visible horizontal area of the &drm_crtc.
71  * CRTC_H:
72  * 	Height for the destination rectangle. CRTC_Y plus CRTC_H can extend past
73  * 	the currently visible vertical area of the &drm_crtc.
74  * FB_ID:
75  * 	Mode object ID of the &drm_framebuffer this plane should scan out.
76  * CRTC_ID:
77  * 	Mode object ID of the &drm_crtc this plane should be connected to.
78  *
79  * Note that the source rectangle must fully lie within the bounds of the
80  * &drm_framebuffer. The destination rectangle can lie outside of the visible
81  * area of the current mode of the CRTC. It must be apprpriately clipped by the
82  * driver, which can be done by calling drm_plane_helper_check_update(). Drivers
83  * are also allowed to round the subpixel sampling positions appropriately, but
84  * only to the next full pixel. No pixel outside of the source rectangle may
85  * ever be sampled, which is important when applying more sophisticated
86  * filtering than just a bilinear one when scaling. The filtering mode when
87  * scaling is unspecified.
88  *
89  * On top of this basic transformation additional properties can be exposed by
90  * the driver:
91  *
92  * - Rotation is set up with drm_mode_create_rotation_property(). It adds a
93  *   rotation and reflection step between the source and destination rectangles.
94  *   Without this property the rectangle is only scaled, but not rotated or
95  *   reflected.
96  *
97  * - Z position is set up with drm_plane_create_zpos_immutable_property() and
98  *   drm_plane_create_zpos_property(). It controls the visibility of overlapping
99  *   planes. Without this property the primary plane is always below the cursor
100  *   plane, and ordering between all other planes is undefined.
101  *
102  * Note that all the property extensions described here apply either to the
103  * plane or the CRTC (e.g. for the background color, which currently is not
104  * exposed and assumed to be black).
105  */
106 
107 /**
108  * drm_mode_create_rotation_property - create a new rotation property
109  * @dev: DRM device
110  * @supported_rotations: bitmask of supported rotations and reflections
111  *
112  * This creates a new property with the selected support for transformations.
113  * The resulting property should be stored in @rotation_property in
114  * &drm_mode_config. It then must be attached to each plane which supports
115  * rotations using drm_object_attach_property().
116  *
117  * FIXME: Probably better if the rotation property is created on each plane,
118  * like the zpos property. Otherwise it's not possible to allow different
119  * rotation modes on different planes.
120  *
121  * Since a rotation by 180° degress is the same as reflecting both along the x
122  * and the y axis the rotation property is somewhat redundant. Drivers can use
123  * drm_rotation_simplify() to normalize values of this property.
124  *
125  * The property exposed to userspace is a bitmask property (see
126  * drm_property_create_bitmask()) called "rotation" and has the following
127  * bitmask enumaration values:
128  *
129  * DRM_ROTATE_0:
130  * 	"rotate-0"
131  * DRM_ROTATE_90:
132  * 	"rotate-90"
133  * DRM_ROTATE_180:
134  * 	"rotate-180"
135  * DRM_ROTATE_270:
136  * 	"rotate-270"
137  * DRM_REFLECT_X:
138  * 	"reflect-x"
139  * DRM_REFELCT_Y:
140  * 	"reflect-y"
141  *
142  * Rotation is the specified amount in degrees in counter clockwise direction,
143  * the X and Y axis are within the source rectangle, i.e.  the X/Y axis before
144  * rotation. After reflection, the rotation is applied to the image sampled from
145  * the source rectangle, before scaling it to fit the destination rectangle.
146  */
147 struct drm_property *drm_mode_create_rotation_property(struct drm_device *dev,
148 						       unsigned int supported_rotations)
149 {
150 	static const struct drm_prop_enum_list props[] = {
151 		{ __builtin_ffs(DRM_ROTATE_0) - 1,   "rotate-0" },
152 		{ __builtin_ffs(DRM_ROTATE_90) - 1,  "rotate-90" },
153 		{ __builtin_ffs(DRM_ROTATE_180) - 1, "rotate-180" },
154 		{ __builtin_ffs(DRM_ROTATE_270) - 1, "rotate-270" },
155 		{ __builtin_ffs(DRM_REFLECT_X) - 1,  "reflect-x" },
156 		{ __builtin_ffs(DRM_REFLECT_Y) - 1,  "reflect-y" },
157 	};
158 
159 	return drm_property_create_bitmask(dev, 0, "rotation",
160 					   props, ARRAY_SIZE(props),
161 					   supported_rotations);
162 }
163 EXPORT_SYMBOL(drm_mode_create_rotation_property);
164 
165 /**
166  * drm_rotation_simplify() - Try to simplify the rotation
167  * @rotation: Rotation to be simplified
168  * @supported_rotations: Supported rotations
169  *
170  * Attempt to simplify the rotation to a form that is supported.
171  * Eg. if the hardware supports everything except DRM_REFLECT_X
172  * one could call this function like this:
173  *
174  * drm_rotation_simplify(rotation, DRM_ROTATE_0 |
175  *                       DRM_ROTATE_90 | DRM_ROTATE_180 |
176  *                       DRM_ROTATE_270 | DRM_REFLECT_Y);
177  *
178  * to eliminate the DRM_ROTATE_X flag. Depending on what kind of
179  * transforms the hardware supports, this function may not
180  * be able to produce a supported transform, so the caller should
181  * check the result afterwards.
182  */
183 unsigned int drm_rotation_simplify(unsigned int rotation,
184 				   unsigned int supported_rotations)
185 {
186 	if (rotation & ~supported_rotations) {
187 		rotation ^= DRM_REFLECT_X | DRM_REFLECT_Y;
188 		rotation = (rotation & DRM_REFLECT_MASK) |
189 		           BIT((ffs(rotation & DRM_ROTATE_MASK) + 1) % 4);
190 	}
191 
192 	return rotation;
193 }
194 EXPORT_SYMBOL(drm_rotation_simplify);
195 
196 /**
197  * drm_plane_create_zpos_property - create mutable zpos property
198  * @plane: drm plane
199  * @zpos: initial value of zpos property
200  * @min: minimal possible value of zpos property
201  * @max: maximal possible value of zpos property
202  *
203  * This function initializes generic mutable zpos property and enables support
204  * for it in drm core. Drivers can then attach this property to planes to enable
205  * support for configurable planes arrangement during blending operation.
206  * Once mutable zpos property has been enabled, the DRM core will automatically
207  * calculate drm_plane_state->normalized_zpos values. Usually min should be set
208  * to 0 and max to maximal number of planes for given crtc - 1.
209  *
210  * If zpos of some planes cannot be changed (like fixed background or
211  * cursor/topmost planes), driver should adjust min/max values and assign those
212  * planes immutable zpos property with lower or higher values (for more
213  * information, see drm_plane_create_zpos_immutable_property() function). In such
214  * case driver should also assign proper initial zpos values for all planes in
215  * its plane_reset() callback, so the planes will be always sorted properly.
216  *
217  * See also drm_atomic_normalize_zpos().
218  *
219  * The property exposed to userspace is called "zpos".
220  *
221  * Returns:
222  * Zero on success, negative errno on failure.
223  */
224 int drm_plane_create_zpos_property(struct drm_plane *plane,
225 				   unsigned int zpos,
226 				   unsigned int min, unsigned int max)
227 {
228 	struct drm_property *prop;
229 
230 	prop = drm_property_create_range(plane->dev, 0, "zpos", min, max);
231 	if (!prop)
232 		return -ENOMEM;
233 
234 	drm_object_attach_property(&plane->base, prop, zpos);
235 
236 	plane->zpos_property = prop;
237 
238 	if (plane->state) {
239 		plane->state->zpos = zpos;
240 		plane->state->normalized_zpos = zpos;
241 	}
242 
243 	return 0;
244 }
245 EXPORT_SYMBOL(drm_plane_create_zpos_property);
246 
247 /**
248  * drm_plane_create_zpos_immutable_property - create immuttable zpos property
249  * @plane: drm plane
250  * @zpos: value of zpos property
251  *
252  * This function initializes generic immutable zpos property and enables
253  * support for it in drm core. Using this property driver lets userspace
254  * to get the arrangement of the planes for blending operation and notifies
255  * it that the hardware (or driver) doesn't support changing of the planes'
256  * order. For mutable zpos see drm_plane_create_zpos_property().
257  *
258  * The property exposed to userspace is called "zpos".
259  *
260  * Returns:
261  * Zero on success, negative errno on failure.
262  */
263 int drm_plane_create_zpos_immutable_property(struct drm_plane *plane,
264 					     unsigned int zpos)
265 {
266 	struct drm_property *prop;
267 
268 	prop = drm_property_create_range(plane->dev, DRM_MODE_PROP_IMMUTABLE,
269 					 "zpos", zpos, zpos);
270 	if (!prop)
271 		return -ENOMEM;
272 
273 	drm_object_attach_property(&plane->base, prop, zpos);
274 
275 	plane->zpos_property = prop;
276 
277 	if (plane->state) {
278 		plane->state->zpos = zpos;
279 		plane->state->normalized_zpos = zpos;
280 	}
281 
282 	return 0;
283 }
284 EXPORT_SYMBOL(drm_plane_create_zpos_immutable_property);
285 
286 static int drm_atomic_state_zpos_cmp(const void *a, const void *b)
287 {
288 	const struct drm_plane_state *sa = *(struct drm_plane_state **)a;
289 	const struct drm_plane_state *sb = *(struct drm_plane_state **)b;
290 
291 	if (sa->zpos != sb->zpos)
292 		return sa->zpos - sb->zpos;
293 	else
294 		return sa->plane->base.id - sb->plane->base.id;
295 }
296 
297 static int drm_atomic_helper_crtc_normalize_zpos(struct drm_crtc *crtc,
298 					  struct drm_crtc_state *crtc_state)
299 {
300 	struct drm_atomic_state *state = crtc_state->state;
301 	struct drm_device *dev = crtc->dev;
302 	int total_planes = dev->mode_config.num_total_plane;
303 	struct drm_plane_state **states;
304 	struct drm_plane *plane;
305 	int i, n = 0;
306 	int ret = 0;
307 
308 	DRM_DEBUG_ATOMIC("[CRTC:%d:%s] calculating normalized zpos values\n",
309 			 crtc->base.id, crtc->name);
310 
311 	states = kmalloc_array(total_planes, sizeof(*states), GFP_TEMPORARY);
312 	if (!states)
313 		return -ENOMEM;
314 
315 	/*
316 	 * Normalization process might create new states for planes which
317 	 * normalized_zpos has to be recalculated.
318 	 */
319 	drm_for_each_plane_mask(plane, dev, crtc_state->plane_mask) {
320 		struct drm_plane_state *plane_state =
321 			drm_atomic_get_plane_state(state, plane);
322 		if (IS_ERR(plane_state)) {
323 			ret = PTR_ERR(plane_state);
324 			goto done;
325 		}
326 		states[n++] = plane_state;
327 		DRM_DEBUG_ATOMIC("[PLANE:%d:%s] processing zpos value %d\n",
328 				 plane->base.id, plane->name,
329 				 plane_state->zpos);
330 	}
331 
332 	sort(states, n, sizeof(*states), drm_atomic_state_zpos_cmp, NULL);
333 
334 	for (i = 0; i < n; i++) {
335 		plane = states[i]->plane;
336 
337 		states[i]->normalized_zpos = i;
338 		DRM_DEBUG_ATOMIC("[PLANE:%d:%s] normalized zpos value %d\n",
339 				 plane->base.id, plane->name, i);
340 	}
341 	crtc_state->zpos_changed = true;
342 
343 done:
344 	kfree(states);
345 	return ret;
346 }
347 
348 /**
349  * drm_atomic_normalize_zpos - calculate normalized zpos values for all crtcs
350  * @dev: DRM device
351  * @state: atomic state of DRM device
352  *
353  * This function calculates normalized zpos value for all modified planes in
354  * the provided atomic state of DRM device.
355  *
356  * For every CRTC this function checks new states of all planes assigned to
357  * it and calculates normalized zpos value for these planes. Planes are compared
358  * first by their zpos values, then by plane id (if zpos is equal). The plane
359  * with lowest zpos value is at the bottom. The plane_state->normalized_zpos is
360  * then filled with unique values from 0 to number of active planes in crtc
361  * minus one.
362  *
363  * RETURNS
364  * Zero for success or -errno
365  */
366 int drm_atomic_normalize_zpos(struct drm_device *dev,
367 			      struct drm_atomic_state *state)
368 {
369 	struct drm_crtc *crtc;
370 	struct drm_crtc_state *crtc_state;
371 	struct drm_plane *plane;
372 	struct drm_plane_state *plane_state;
373 	int i, ret = 0;
374 
375 	for_each_plane_in_state(state, plane, plane_state, i) {
376 		crtc = plane_state->crtc;
377 		if (!crtc)
378 			continue;
379 		if (plane->state->zpos != plane_state->zpos) {
380 			crtc_state =
381 				drm_atomic_get_existing_crtc_state(state, crtc);
382 			crtc_state->zpos_changed = true;
383 		}
384 	}
385 
386 	for_each_crtc_in_state(state, crtc, crtc_state, i) {
387 		if (crtc_state->plane_mask != crtc->state->plane_mask ||
388 		    crtc_state->zpos_changed) {
389 			ret = drm_atomic_helper_crtc_normalize_zpos(crtc,
390 								    crtc_state);
391 			if (ret)
392 				return ret;
393 		}
394 	}
395 	return 0;
396 }
397 EXPORT_SYMBOL(drm_atomic_normalize_zpos);
398