xref: /openbmc/linux/include/drm/drm_crtc.h (revision fb8d6c8d)
1 /*
2  * Copyright © 2006 Keith Packard
3  * Copyright © 2007-2008 Dave Airlie
4  * Copyright © 2007-2008 Intel Corporation
5  *   Jesse Barnes <jesse.barnes@intel.com>
6  *
7  * Permission is hereby granted, free of charge, to any person obtaining a
8  * copy of this software and associated documentation files (the "Software"),
9  * to deal in the Software without restriction, including without limitation
10  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
11  * and/or sell copies of the Software, and to permit persons to whom the
12  * Software is furnished to do so, subject to the following conditions:
13  *
14  * The above copyright notice and this permission notice shall be included in
15  * all copies or substantial portions of the Software.
16  *
17  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
18  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
19  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
20  * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
21  * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
22  * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
23  * OTHER DEALINGS IN THE SOFTWARE.
24  */
25 #ifndef __DRM_CRTC_H__
26 #define __DRM_CRTC_H__
27 
28 #include <linux/i2c.h>
29 #include <linux/spinlock.h>
30 #include <linux/types.h>
31 #include <linux/fb.h>
32 #include <linux/hdmi.h>
33 #include <linux/media-bus-format.h>
34 #include <uapi/drm/drm_mode.h>
35 #include <uapi/drm/drm_fourcc.h>
36 #include <drm/drm_modeset_lock.h>
37 #include <drm/drm_rect.h>
38 #include <drm/drm_mode_object.h>
39 #include <drm/drm_framebuffer.h>
40 #include <drm/drm_modes.h>
41 #include <drm/drm_connector.h>
42 #include <drm/drm_device.h>
43 #include <drm/drm_property.h>
44 #include <drm/drm_bridge.h>
45 #include <drm/drm_edid.h>
46 #include <drm/drm_plane.h>
47 #include <drm/drm_blend.h>
48 #include <drm/drm_color_mgmt.h>
49 #include <drm/drm_debugfs_crc.h>
50 #include <drm/drm_mode_config.h>
51 
52 struct drm_device;
53 struct drm_mode_set;
54 struct drm_file;
55 struct drm_clip_rect;
56 struct drm_printer;
57 struct drm_self_refresh_data;
58 struct device_node;
59 struct dma_fence;
60 struct edid;
61 
62 static inline int64_t U642I64(uint64_t val)
63 {
64 	return (int64_t)*((int64_t *)&val);
65 }
66 static inline uint64_t I642U64(int64_t val)
67 {
68 	return (uint64_t)*((uint64_t *)&val);
69 }
70 
71 struct drm_crtc;
72 struct drm_pending_vblank_event;
73 struct drm_plane;
74 struct drm_bridge;
75 struct drm_atomic_state;
76 
77 struct drm_crtc_helper_funcs;
78 struct drm_plane_helper_funcs;
79 
80 /**
81  * struct drm_crtc_state - mutable CRTC state
82  *
83  * Note that the distinction between @enable and @active is rather subtle:
84  * Flipping @active while @enable is set without changing anything else may
85  * never return in a failure from the &drm_mode_config_funcs.atomic_check
86  * callback. Userspace assumes that a DPMS On will always succeed. In other
87  * words: @enable controls resource assignment, @active controls the actual
88  * hardware state.
89  *
90  * The three booleans active_changed, connectors_changed and mode_changed are
91  * intended to indicate whether a full modeset is needed, rather than strictly
92  * describing what has changed in a commit. See also:
93  * drm_atomic_crtc_needs_modeset()
94  *
95  * WARNING: Transitional helpers (like drm_helper_crtc_mode_set() or
96  * drm_helper_crtc_mode_set_base()) do not maintain many of the derived control
97  * state like @plane_mask so drivers not converted over to atomic helpers should
98  * not rely on these being accurate!
99  */
100 struct drm_crtc_state {
101 	/** @crtc: backpointer to the CRTC */
102 	struct drm_crtc *crtc;
103 
104 	/**
105 	 * @enable: Whether the CRTC should be enabled, gates all other state.
106 	 * This controls reservations of shared resources. Actual hardware state
107 	 * is controlled by @active.
108 	 */
109 	bool enable;
110 
111 	/**
112 	 * @active: Whether the CRTC is actively displaying (used for DPMS).
113 	 * Implies that @enable is set. The driver must not release any shared
114 	 * resources if @active is set to false but @enable still true, because
115 	 * userspace expects that a DPMS ON always succeeds.
116 	 *
117 	 * Hence drivers must not consult @active in their various
118 	 * &drm_mode_config_funcs.atomic_check callback to reject an atomic
119 	 * commit. They can consult it to aid in the computation of derived
120 	 * hardware state, since even in the DPMS OFF state the display hardware
121 	 * should be as much powered down as when the CRTC is completely
122 	 * disabled through setting @enable to false.
123 	 */
124 	bool active;
125 
126 	/**
127 	 * @planes_changed: Planes on this crtc are updated. Used by the atomic
128 	 * helpers and drivers to steer the atomic commit control flow.
129 	 */
130 	bool planes_changed : 1;
131 
132 	/**
133 	 * @mode_changed: @mode or @enable has been changed. Used by the atomic
134 	 * helpers and drivers to steer the atomic commit control flow. See also
135 	 * drm_atomic_crtc_needs_modeset().
136 	 *
137 	 * Drivers are supposed to set this for any CRTC state changes that
138 	 * require a full modeset. They can also reset it to false if e.g. a
139 	 * @mode change can be done without a full modeset by only changing
140 	 * scaler settings.
141 	 */
142 	bool mode_changed : 1;
143 
144 	/**
145 	 * @active_changed: @active has been toggled. Used by the atomic
146 	 * helpers and drivers to steer the atomic commit control flow. See also
147 	 * drm_atomic_crtc_needs_modeset().
148 	 */
149 	bool active_changed : 1;
150 
151 	/**
152 	 * @connectors_changed: Connectors to this crtc have been updated,
153 	 * either in their state or routing. Used by the atomic
154 	 * helpers and drivers to steer the atomic commit control flow. See also
155 	 * drm_atomic_crtc_needs_modeset().
156 	 *
157 	 * Drivers are supposed to set this as-needed from their own atomic
158 	 * check code, e.g. from &drm_encoder_helper_funcs.atomic_check
159 	 */
160 	bool connectors_changed : 1;
161 	/**
162 	 * @zpos_changed: zpos values of planes on this crtc have been updated.
163 	 * Used by the atomic helpers and drivers to steer the atomic commit
164 	 * control flow.
165 	 */
166 	bool zpos_changed : 1;
167 	/**
168 	 * @color_mgmt_changed: Color management properties have changed
169 	 * (@gamma_lut, @degamma_lut or @ctm). Used by the atomic helpers and
170 	 * drivers to steer the atomic commit control flow.
171 	 */
172 	bool color_mgmt_changed : 1;
173 
174 	/**
175 	 * @no_vblank:
176 	 *
177 	 * Reflects the ability of a CRTC to send VBLANK events. This state
178 	 * usually depends on the pipeline configuration, and the main usuage
179 	 * is CRTCs feeding a writeback connector operating in oneshot mode.
180 	 * In this case the VBLANK event is only generated when a job is queued
181 	 * to the writeback connector, and we want the core to fake VBLANK
182 	 * events when this part of the pipeline hasn't changed but others had
183 	 * or when the CRTC and connectors are being disabled.
184 	 *
185 	 * __drm_atomic_helper_crtc_duplicate_state() will not reset the value
186 	 * from the current state, the CRTC driver is then responsible for
187 	 * updating this field when needed.
188 	 *
189 	 * Note that the combination of &drm_crtc_state.event == NULL and
190 	 * &drm_crtc_state.no_blank == true is valid and usually used when the
191 	 * writeback connector attached to the CRTC has a new job queued. In
192 	 * this case the driver will send the VBLANK event on its own when the
193 	 * writeback job is complete.
194 	 */
195 	bool no_vblank : 1;
196 
197 	/**
198 	 * @plane_mask: Bitmask of drm_plane_mask(plane) of planes attached to
199 	 * this CRTC.
200 	 */
201 	u32 plane_mask;
202 
203 	/**
204 	 * @connector_mask: Bitmask of drm_connector_mask(connector) of
205 	 * connectors attached to this CRTC.
206 	 */
207 	u32 connector_mask;
208 
209 	/**
210 	 * @encoder_mask: Bitmask of drm_encoder_mask(encoder) of encoders
211 	 * attached to this CRTC.
212 	 */
213 	u32 encoder_mask;
214 
215 	/**
216 	 * @adjusted_mode:
217 	 *
218 	 * Internal display timings which can be used by the driver to handle
219 	 * differences between the mode requested by userspace in @mode and what
220 	 * is actually programmed into the hardware.
221 	 *
222 	 * For drivers using &drm_bridge, this stores hardware display timings
223 	 * used between the CRTC and the first bridge. For other drivers, the
224 	 * meaning of the adjusted_mode field is purely driver implementation
225 	 * defined information, and will usually be used to store the hardware
226 	 * display timings used between the CRTC and encoder blocks.
227 	 */
228 	struct drm_display_mode adjusted_mode;
229 
230 	/**
231 	 * @mode:
232 	 *
233 	 * Display timings requested by userspace. The driver should try to
234 	 * match the refresh rate as close as possible (but note that it's
235 	 * undefined what exactly is close enough, e.g. some of the HDMI modes
236 	 * only differ in less than 1% of the refresh rate). The active width
237 	 * and height as observed by userspace for positioning planes must match
238 	 * exactly.
239 	 *
240 	 * For external connectors where the sink isn't fixed (like with a
241 	 * built-in panel), this mode here should match the physical mode on the
242 	 * wire to the last details (i.e. including sync polarities and
243 	 * everything).
244 	 */
245 	struct drm_display_mode mode;
246 
247 	/**
248 	 * @mode_blob: &drm_property_blob for @mode, for exposing the mode to
249 	 * atomic userspace.
250 	 */
251 	struct drm_property_blob *mode_blob;
252 
253 	/**
254 	 * @degamma_lut:
255 	 *
256 	 * Lookup table for converting framebuffer pixel data before apply the
257 	 * color conversion matrix @ctm. See drm_crtc_enable_color_mgmt(). The
258 	 * blob (if not NULL) is an array of &struct drm_color_lut.
259 	 */
260 	struct drm_property_blob *degamma_lut;
261 
262 	/**
263 	 * @ctm:
264 	 *
265 	 * Color transformation matrix. See drm_crtc_enable_color_mgmt(). The
266 	 * blob (if not NULL) is a &struct drm_color_ctm.
267 	 */
268 	struct drm_property_blob *ctm;
269 
270 	/**
271 	 * @gamma_lut:
272 	 *
273 	 * Lookup table for converting pixel data after the color conversion
274 	 * matrix @ctm.  See drm_crtc_enable_color_mgmt(). The blob (if not
275 	 * NULL) is an array of &struct drm_color_lut.
276 	 */
277 	struct drm_property_blob *gamma_lut;
278 
279 	/**
280 	 * @target_vblank:
281 	 *
282 	 * Target vertical blank period when a page flip
283 	 * should take effect.
284 	 */
285 	u32 target_vblank;
286 
287 	/**
288 	 * @async_flip:
289 	 *
290 	 * This is set when DRM_MODE_PAGE_FLIP_ASYNC is set in the legacy
291 	 * PAGE_FLIP IOCTL. It's not wired up for the atomic IOCTL itself yet.
292 	 */
293 	bool async_flip;
294 
295 	/**
296 	 * @vrr_enabled:
297 	 *
298 	 * Indicates if variable refresh rate should be enabled for the CRTC.
299 	 * Support for the requested vrr state will depend on driver and
300 	 * hardware capabiltiy - lacking support is not treated as failure.
301 	 */
302 	bool vrr_enabled;
303 
304 	/**
305 	 * @self_refresh_active:
306 	 *
307 	 * Used by the self refresh helpers to denote when a self refresh
308 	 * transition is occurring. This will be set on enable/disable callbacks
309 	 * when self refresh is being enabled or disabled. In some cases, it may
310 	 * not be desirable to fully shut off the crtc during self refresh.
311 	 * CRTC's can inspect this flag and determine the best course of action.
312 	 */
313 	bool self_refresh_active;
314 
315 	/**
316 	 * @event:
317 	 *
318 	 * Optional pointer to a DRM event to signal upon completion of the
319 	 * state update. The driver must send out the event when the atomic
320 	 * commit operation completes. There are two cases:
321 	 *
322 	 *  - The event is for a CRTC which is being disabled through this
323 	 *    atomic commit. In that case the event can be send out any time
324 	 *    after the hardware has stopped scanning out the current
325 	 *    framebuffers. It should contain the timestamp and counter for the
326 	 *    last vblank before the display pipeline was shut off. The simplest
327 	 *    way to achieve that is calling drm_crtc_send_vblank_event()
328 	 *    somewhen after drm_crtc_vblank_off() has been called.
329 	 *
330 	 *  - For a CRTC which is enabled at the end of the commit (even when it
331 	 *    undergoes an full modeset) the vblank timestamp and counter must
332 	 *    be for the vblank right before the first frame that scans out the
333 	 *    new set of buffers. Again the event can only be sent out after the
334 	 *    hardware has stopped scanning out the old buffers.
335 	 *
336 	 *  - Events for disabled CRTCs are not allowed, and drivers can ignore
337 	 *    that case.
338 	 *
339 	 * This can be handled by the drm_crtc_send_vblank_event() function,
340 	 * which the driver should call on the provided event upon completion of
341 	 * the atomic commit. Note that if the driver supports vblank signalling
342 	 * and timestamping the vblank counters and timestamps must agree with
343 	 * the ones returned from page flip events. With the current vblank
344 	 * helper infrastructure this can be achieved by holding a vblank
345 	 * reference while the page flip is pending, acquired through
346 	 * drm_crtc_vblank_get() and released with drm_crtc_vblank_put().
347 	 * Drivers are free to implement their own vblank counter and timestamp
348 	 * tracking though, e.g. if they have accurate timestamp registers in
349 	 * hardware.
350 	 *
351 	 * For hardware which supports some means to synchronize vblank
352 	 * interrupt delivery with committing display state there's also
353 	 * drm_crtc_arm_vblank_event(). See the documentation of that function
354 	 * for a detailed discussion of the constraints it needs to be used
355 	 * safely.
356 	 *
357 	 * If the device can't notify of flip completion in a race-free way
358 	 * at all, then the event should be armed just after the page flip is
359 	 * committed. In the worst case the driver will send the event to
360 	 * userspace one frame too late. This doesn't allow for a real atomic
361 	 * update, but it should avoid tearing.
362 	 */
363 	struct drm_pending_vblank_event *event;
364 
365 	/**
366 	 * @commit:
367 	 *
368 	 * This tracks how the commit for this update proceeds through the
369 	 * various phases. This is never cleared, except when we destroy the
370 	 * state, so that subsequent commits can synchronize with previous ones.
371 	 */
372 	struct drm_crtc_commit *commit;
373 
374 	/** @state: backpointer to global drm_atomic_state */
375 	struct drm_atomic_state *state;
376 };
377 
378 /**
379  * struct drm_crtc_funcs - control CRTCs for a given device
380  *
381  * The drm_crtc_funcs structure is the central CRTC management structure
382  * in the DRM.  Each CRTC controls one or more connectors (note that the name
383  * CRTC is simply historical, a CRTC may control LVDS, VGA, DVI, TV out, etc.
384  * connectors, not just CRTs).
385  *
386  * Each driver is responsible for filling out this structure at startup time,
387  * in addition to providing other modesetting features, like i2c and DDC
388  * bus accessors.
389  */
390 struct drm_crtc_funcs {
391 	/**
392 	 * @reset:
393 	 *
394 	 * Reset CRTC hardware and software state to off. This function isn't
395 	 * called by the core directly, only through drm_mode_config_reset().
396 	 * It's not a helper hook only for historical reasons.
397 	 *
398 	 * Atomic drivers can use drm_atomic_helper_crtc_reset() to reset
399 	 * atomic state using this hook.
400 	 */
401 	void (*reset)(struct drm_crtc *crtc);
402 
403 	/**
404 	 * @cursor_set:
405 	 *
406 	 * Update the cursor image. The cursor position is relative to the CRTC
407 	 * and can be partially or fully outside of the visible area.
408 	 *
409 	 * Note that contrary to all other KMS functions the legacy cursor entry
410 	 * points don't take a framebuffer object, but instead take directly a
411 	 * raw buffer object id from the driver's buffer manager (which is
412 	 * either GEM or TTM for current drivers).
413 	 *
414 	 * This entry point is deprecated, drivers should instead implement
415 	 * universal plane support and register a proper cursor plane using
416 	 * drm_crtc_init_with_planes().
417 	 *
418 	 * This callback is optional
419 	 *
420 	 * RETURNS:
421 	 *
422 	 * 0 on success or a negative error code on failure.
423 	 */
424 	int (*cursor_set)(struct drm_crtc *crtc, struct drm_file *file_priv,
425 			  uint32_t handle, uint32_t width, uint32_t height);
426 
427 	/**
428 	 * @cursor_set2:
429 	 *
430 	 * Update the cursor image, including hotspot information. The hotspot
431 	 * must not affect the cursor position in CRTC coordinates, but is only
432 	 * meant as a hint for virtualized display hardware to coordinate the
433 	 * guests and hosts cursor position. The cursor hotspot is relative to
434 	 * the cursor image. Otherwise this works exactly like @cursor_set.
435 	 *
436 	 * This entry point is deprecated, drivers should instead implement
437 	 * universal plane support and register a proper cursor plane using
438 	 * drm_crtc_init_with_planes().
439 	 *
440 	 * This callback is optional.
441 	 *
442 	 * RETURNS:
443 	 *
444 	 * 0 on success or a negative error code on failure.
445 	 */
446 	int (*cursor_set2)(struct drm_crtc *crtc, struct drm_file *file_priv,
447 			   uint32_t handle, uint32_t width, uint32_t height,
448 			   int32_t hot_x, int32_t hot_y);
449 
450 	/**
451 	 * @cursor_move:
452 	 *
453 	 * Update the cursor position. The cursor does not need to be visible
454 	 * when this hook is called.
455 	 *
456 	 * This entry point is deprecated, drivers should instead implement
457 	 * universal plane support and register a proper cursor plane using
458 	 * drm_crtc_init_with_planes().
459 	 *
460 	 * This callback is optional.
461 	 *
462 	 * RETURNS:
463 	 *
464 	 * 0 on success or a negative error code on failure.
465 	 */
466 	int (*cursor_move)(struct drm_crtc *crtc, int x, int y);
467 
468 	/**
469 	 * @gamma_set:
470 	 *
471 	 * Set gamma on the CRTC.
472 	 *
473 	 * This callback is optional.
474 	 *
475 	 * Atomic drivers who want to support gamma tables should implement the
476 	 * atomic color management support, enabled by calling
477 	 * drm_crtc_enable_color_mgmt(), which then supports the legacy gamma
478 	 * interface through the drm_atomic_helper_legacy_gamma_set()
479 	 * compatibility implementation.
480 	 */
481 	int (*gamma_set)(struct drm_crtc *crtc, u16 *r, u16 *g, u16 *b,
482 			 uint32_t size,
483 			 struct drm_modeset_acquire_ctx *ctx);
484 
485 	/**
486 	 * @destroy:
487 	 *
488 	 * Clean up CRTC resources. This is only called at driver unload time
489 	 * through drm_mode_config_cleanup() since a CRTC cannot be hotplugged
490 	 * in DRM.
491 	 */
492 	void (*destroy)(struct drm_crtc *crtc);
493 
494 	/**
495 	 * @set_config:
496 	 *
497 	 * This is the main legacy entry point to change the modeset state on a
498 	 * CRTC. All the details of the desired configuration are passed in a
499 	 * &struct drm_mode_set - see there for details.
500 	 *
501 	 * Drivers implementing atomic modeset should use
502 	 * drm_atomic_helper_set_config() to implement this hook.
503 	 *
504 	 * RETURNS:
505 	 *
506 	 * 0 on success or a negative error code on failure.
507 	 */
508 	int (*set_config)(struct drm_mode_set *set,
509 			  struct drm_modeset_acquire_ctx *ctx);
510 
511 	/**
512 	 * @page_flip:
513 	 *
514 	 * Legacy entry point to schedule a flip to the given framebuffer.
515 	 *
516 	 * Page flipping is a synchronization mechanism that replaces the frame
517 	 * buffer being scanned out by the CRTC with a new frame buffer during
518 	 * vertical blanking, avoiding tearing (except when requested otherwise
519 	 * through the DRM_MODE_PAGE_FLIP_ASYNC flag). When an application
520 	 * requests a page flip the DRM core verifies that the new frame buffer
521 	 * is large enough to be scanned out by the CRTC in the currently
522 	 * configured mode and then calls this hook with a pointer to the new
523 	 * frame buffer.
524 	 *
525 	 * The driver must wait for any pending rendering to the new framebuffer
526 	 * to complete before executing the flip. It should also wait for any
527 	 * pending rendering from other drivers if the underlying buffer is a
528 	 * shared dma-buf.
529 	 *
530 	 * An application can request to be notified when the page flip has
531 	 * completed. The drm core will supply a &struct drm_event in the event
532 	 * parameter in this case. This can be handled by the
533 	 * drm_crtc_send_vblank_event() function, which the driver should call on
534 	 * the provided event upon completion of the flip. Note that if
535 	 * the driver supports vblank signalling and timestamping the vblank
536 	 * counters and timestamps must agree with the ones returned from page
537 	 * flip events. With the current vblank helper infrastructure this can
538 	 * be achieved by holding a vblank reference while the page flip is
539 	 * pending, acquired through drm_crtc_vblank_get() and released with
540 	 * drm_crtc_vblank_put(). Drivers are free to implement their own vblank
541 	 * counter and timestamp tracking though, e.g. if they have accurate
542 	 * timestamp registers in hardware.
543 	 *
544 	 * This callback is optional.
545 	 *
546 	 * NOTE:
547 	 *
548 	 * Very early versions of the KMS ABI mandated that the driver must
549 	 * block (but not reject) any rendering to the old framebuffer until the
550 	 * flip operation has completed and the old framebuffer is no longer
551 	 * visible. This requirement has been lifted, and userspace is instead
552 	 * expected to request delivery of an event and wait with recycling old
553 	 * buffers until such has been received.
554 	 *
555 	 * RETURNS:
556 	 *
557 	 * 0 on success or a negative error code on failure. Note that if a
558 	 * page flip operation is already pending the callback should return
559 	 * -EBUSY. Pageflips on a disabled CRTC (either by setting a NULL mode
560 	 * or just runtime disabled through DPMS respectively the new atomic
561 	 * "ACTIVE" state) should result in an -EINVAL error code. Note that
562 	 * drm_atomic_helper_page_flip() checks this already for atomic drivers.
563 	 */
564 	int (*page_flip)(struct drm_crtc *crtc,
565 			 struct drm_framebuffer *fb,
566 			 struct drm_pending_vblank_event *event,
567 			 uint32_t flags,
568 			 struct drm_modeset_acquire_ctx *ctx);
569 
570 	/**
571 	 * @page_flip_target:
572 	 *
573 	 * Same as @page_flip but with an additional parameter specifying the
574 	 * absolute target vertical blank period (as reported by
575 	 * drm_crtc_vblank_count()) when the flip should take effect.
576 	 *
577 	 * Note that the core code calls drm_crtc_vblank_get before this entry
578 	 * point, and will call drm_crtc_vblank_put if this entry point returns
579 	 * any non-0 error code. It's the driver's responsibility to call
580 	 * drm_crtc_vblank_put after this entry point returns 0, typically when
581 	 * the flip completes.
582 	 */
583 	int (*page_flip_target)(struct drm_crtc *crtc,
584 				struct drm_framebuffer *fb,
585 				struct drm_pending_vblank_event *event,
586 				uint32_t flags, uint32_t target,
587 				struct drm_modeset_acquire_ctx *ctx);
588 
589 	/**
590 	 * @set_property:
591 	 *
592 	 * This is the legacy entry point to update a property attached to the
593 	 * CRTC.
594 	 *
595 	 * This callback is optional if the driver does not support any legacy
596 	 * driver-private properties. For atomic drivers it is not used because
597 	 * property handling is done entirely in the DRM core.
598 	 *
599 	 * RETURNS:
600 	 *
601 	 * 0 on success or a negative error code on failure.
602 	 */
603 	int (*set_property)(struct drm_crtc *crtc,
604 			    struct drm_property *property, uint64_t val);
605 
606 	/**
607 	 * @atomic_duplicate_state:
608 	 *
609 	 * Duplicate the current atomic state for this CRTC and return it.
610 	 * The core and helpers guarantee that any atomic state duplicated with
611 	 * this hook and still owned by the caller (i.e. not transferred to the
612 	 * driver by calling &drm_mode_config_funcs.atomic_commit) will be
613 	 * cleaned up by calling the @atomic_destroy_state hook in this
614 	 * structure.
615 	 *
616 	 * This callback is mandatory for atomic drivers.
617 	 *
618 	 * Atomic drivers which don't subclass &struct drm_crtc_state should use
619 	 * drm_atomic_helper_crtc_duplicate_state(). Drivers that subclass the
620 	 * state structure to extend it with driver-private state should use
621 	 * __drm_atomic_helper_crtc_duplicate_state() to make sure shared state is
622 	 * duplicated in a consistent fashion across drivers.
623 	 *
624 	 * It is an error to call this hook before &drm_crtc.state has been
625 	 * initialized correctly.
626 	 *
627 	 * NOTE:
628 	 *
629 	 * If the duplicate state references refcounted resources this hook must
630 	 * acquire a reference for each of them. The driver must release these
631 	 * references again in @atomic_destroy_state.
632 	 *
633 	 * RETURNS:
634 	 *
635 	 * Duplicated atomic state or NULL when the allocation failed.
636 	 */
637 	struct drm_crtc_state *(*atomic_duplicate_state)(struct drm_crtc *crtc);
638 
639 	/**
640 	 * @atomic_destroy_state:
641 	 *
642 	 * Destroy a state duplicated with @atomic_duplicate_state and release
643 	 * or unreference all resources it references
644 	 *
645 	 * This callback is mandatory for atomic drivers.
646 	 */
647 	void (*atomic_destroy_state)(struct drm_crtc *crtc,
648 				     struct drm_crtc_state *state);
649 
650 	/**
651 	 * @atomic_set_property:
652 	 *
653 	 * Decode a driver-private property value and store the decoded value
654 	 * into the passed-in state structure. Since the atomic core decodes all
655 	 * standardized properties (even for extensions beyond the core set of
656 	 * properties which might not be implemented by all drivers) this
657 	 * requires drivers to subclass the state structure.
658 	 *
659 	 * Such driver-private properties should really only be implemented for
660 	 * truly hardware/vendor specific state. Instead it is preferred to
661 	 * standardize atomic extension and decode the properties used to expose
662 	 * such an extension in the core.
663 	 *
664 	 * Do not call this function directly, use
665 	 * drm_atomic_crtc_set_property() instead.
666 	 *
667 	 * This callback is optional if the driver does not support any
668 	 * driver-private atomic properties.
669 	 *
670 	 * NOTE:
671 	 *
672 	 * This function is called in the state assembly phase of atomic
673 	 * modesets, which can be aborted for any reason (including on
674 	 * userspace's request to just check whether a configuration would be
675 	 * possible). Drivers MUST NOT touch any persistent state (hardware or
676 	 * software) or data structures except the passed in @state parameter.
677 	 *
678 	 * Also since userspace controls in which order properties are set this
679 	 * function must not do any input validation (since the state update is
680 	 * incomplete and hence likely inconsistent). Instead any such input
681 	 * validation must be done in the various atomic_check callbacks.
682 	 *
683 	 * RETURNS:
684 	 *
685 	 * 0 if the property has been found, -EINVAL if the property isn't
686 	 * implemented by the driver (which should never happen, the core only
687 	 * asks for properties attached to this CRTC). No other validation is
688 	 * allowed by the driver. The core already checks that the property
689 	 * value is within the range (integer, valid enum value, ...) the driver
690 	 * set when registering the property.
691 	 */
692 	int (*atomic_set_property)(struct drm_crtc *crtc,
693 				   struct drm_crtc_state *state,
694 				   struct drm_property *property,
695 				   uint64_t val);
696 	/**
697 	 * @atomic_get_property:
698 	 *
699 	 * Reads out the decoded driver-private property. This is used to
700 	 * implement the GETCRTC IOCTL.
701 	 *
702 	 * Do not call this function directly, use
703 	 * drm_atomic_crtc_get_property() instead.
704 	 *
705 	 * This callback is optional if the driver does not support any
706 	 * driver-private atomic properties.
707 	 *
708 	 * RETURNS:
709 	 *
710 	 * 0 on success, -EINVAL if the property isn't implemented by the
711 	 * driver (which should never happen, the core only asks for
712 	 * properties attached to this CRTC).
713 	 */
714 	int (*atomic_get_property)(struct drm_crtc *crtc,
715 				   const struct drm_crtc_state *state,
716 				   struct drm_property *property,
717 				   uint64_t *val);
718 
719 	/**
720 	 * @late_register:
721 	 *
722 	 * This optional hook can be used to register additional userspace
723 	 * interfaces attached to the crtc like debugfs interfaces.
724 	 * It is called late in the driver load sequence from drm_dev_register().
725 	 * Everything added from this callback should be unregistered in
726 	 * the early_unregister callback.
727 	 *
728 	 * Returns:
729 	 *
730 	 * 0 on success, or a negative error code on failure.
731 	 */
732 	int (*late_register)(struct drm_crtc *crtc);
733 
734 	/**
735 	 * @early_unregister:
736 	 *
737 	 * This optional hook should be used to unregister the additional
738 	 * userspace interfaces attached to the crtc from
739 	 * @late_register. It is called from drm_dev_unregister(),
740 	 * early in the driver unload sequence to disable userspace access
741 	 * before data structures are torndown.
742 	 */
743 	void (*early_unregister)(struct drm_crtc *crtc);
744 
745 	/**
746 	 * @set_crc_source:
747 	 *
748 	 * Changes the source of CRC checksums of frames at the request of
749 	 * userspace, typically for testing purposes. The sources available are
750 	 * specific of each driver and a %NULL value indicates that CRC
751 	 * generation is to be switched off.
752 	 *
753 	 * When CRC generation is enabled, the driver should call
754 	 * drm_crtc_add_crc_entry() at each frame, providing any information
755 	 * that characterizes the frame contents in the crcN arguments, as
756 	 * provided from the configured source. Drivers must accept an "auto"
757 	 * source name that will select a default source for this CRTC.
758 	 *
759 	 * This may trigger an atomic modeset commit if necessary, to enable CRC
760 	 * generation.
761 	 *
762 	 * Note that "auto" can depend upon the current modeset configuration,
763 	 * e.g. it could pick an encoder or output specific CRC sampling point.
764 	 *
765 	 * This callback is optional if the driver does not support any CRC
766 	 * generation functionality.
767 	 *
768 	 * RETURNS:
769 	 *
770 	 * 0 on success or a negative error code on failure.
771 	 */
772 	int (*set_crc_source)(struct drm_crtc *crtc, const char *source);
773 
774 	/**
775 	 * @verify_crc_source:
776 	 *
777 	 * verifies the source of CRC checksums of frames before setting the
778 	 * source for CRC and during crc open. Source parameter can be NULL
779 	 * while disabling crc source.
780 	 *
781 	 * This callback is optional if the driver does not support any CRC
782 	 * generation functionality.
783 	 *
784 	 * RETURNS:
785 	 *
786 	 * 0 on success or a negative error code on failure.
787 	 */
788 	int (*verify_crc_source)(struct drm_crtc *crtc, const char *source,
789 				 size_t *values_cnt);
790 	/**
791 	 * @get_crc_sources:
792 	 *
793 	 * Driver callback for getting a list of all the available sources for
794 	 * CRC generation. This callback depends upon verify_crc_source, So
795 	 * verify_crc_source callback should be implemented before implementing
796 	 * this. Driver can pass full list of available crc sources, this
797 	 * callback does the verification on each crc-source before passing it
798 	 * to userspace.
799 	 *
800 	 * This callback is optional if the driver does not support exporting of
801 	 * possible CRC sources list.
802 	 *
803 	 * RETURNS:
804 	 *
805 	 * a constant character pointer to the list of all the available CRC
806 	 * sources. On failure driver should return NULL. count should be
807 	 * updated with number of sources in list. if zero we don't process any
808 	 * source from the list.
809 	 */
810 	const char *const *(*get_crc_sources)(struct drm_crtc *crtc,
811 					      size_t *count);
812 
813 	/**
814 	 * @atomic_print_state:
815 	 *
816 	 * If driver subclasses &struct drm_crtc_state, it should implement
817 	 * this optional hook for printing additional driver specific state.
818 	 *
819 	 * Do not call this directly, use drm_atomic_crtc_print_state()
820 	 * instead.
821 	 */
822 	void (*atomic_print_state)(struct drm_printer *p,
823 				   const struct drm_crtc_state *state);
824 
825 	/**
826 	 * @get_vblank_counter:
827 	 *
828 	 * Driver callback for fetching a raw hardware vblank counter for the
829 	 * CRTC. It's meant to be used by new drivers as the replacement of
830 	 * &drm_driver.get_vblank_counter hook.
831 	 *
832 	 * This callback is optional. If a device doesn't have a hardware
833 	 * counter, the driver can simply leave the hook as NULL. The DRM core
834 	 * will account for missed vblank events while interrupts where disabled
835 	 * based on system timestamps.
836 	 *
837 	 * Wraparound handling and loss of events due to modesetting is dealt
838 	 * with in the DRM core code, as long as drivers call
839 	 * drm_crtc_vblank_off() and drm_crtc_vblank_on() when disabling or
840 	 * enabling a CRTC.
841 	 *
842 	 * See also &drm_device.vblank_disable_immediate and
843 	 * &drm_device.max_vblank_count.
844 	 *
845 	 * Returns:
846 	 *
847 	 * Raw vblank counter value.
848 	 */
849 	u32 (*get_vblank_counter)(struct drm_crtc *crtc);
850 
851 	/**
852 	 * @enable_vblank:
853 	 *
854 	 * Enable vblank interrupts for the CRTC. It's meant to be used by
855 	 * new drivers as the replacement of &drm_driver.enable_vblank hook.
856 	 *
857 	 * Returns:
858 	 *
859 	 * Zero on success, appropriate errno if the vblank interrupt cannot
860 	 * be enabled.
861 	 */
862 	int (*enable_vblank)(struct drm_crtc *crtc);
863 
864 	/**
865 	 * @disable_vblank:
866 	 *
867 	 * Disable vblank interrupts for the CRTC. It's meant to be used by
868 	 * new drivers as the replacement of &drm_driver.disable_vblank hook.
869 	 */
870 	void (*disable_vblank)(struct drm_crtc *crtc);
871 };
872 
873 /**
874  * struct drm_crtc - central CRTC control structure
875  *
876  * Each CRTC may have one or more connectors associated with it.  This structure
877  * allows the CRTC to be controlled.
878  */
879 struct drm_crtc {
880 	/** @dev: parent DRM device */
881 	struct drm_device *dev;
882 	/** @port: OF node used by drm_of_find_possible_crtcs(). */
883 	struct device_node *port;
884 	/**
885 	 * @head:
886 	 *
887 	 * List of all CRTCs on @dev, linked from &drm_mode_config.crtc_list.
888 	 * Invariant over the lifetime of @dev and therefore does not need
889 	 * locking.
890 	 */
891 	struct list_head head;
892 
893 	/** @name: human readable name, can be overwritten by the driver */
894 	char *name;
895 
896 	/**
897 	 * @mutex:
898 	 *
899 	 * This provides a read lock for the overall CRTC state (mode, dpms
900 	 * state, ...) and a write lock for everything which can be update
901 	 * without a full modeset (fb, cursor data, CRTC properties ...). A full
902 	 * modeset also need to grab &drm_mode_config.connection_mutex.
903 	 *
904 	 * For atomic drivers specifically this protects @state.
905 	 */
906 	struct drm_modeset_lock mutex;
907 
908 	/** @base: base KMS object for ID tracking etc. */
909 	struct drm_mode_object base;
910 
911 	/**
912 	 * @primary:
913 	 * Primary plane for this CRTC. Note that this is only
914 	 * relevant for legacy IOCTL, it specifies the plane implicitly used by
915 	 * the SETCRTC and PAGE_FLIP IOCTLs. It does not have any significance
916 	 * beyond that.
917 	 */
918 	struct drm_plane *primary;
919 
920 	/**
921 	 * @cursor:
922 	 * Cursor plane for this CRTC. Note that this is only relevant for
923 	 * legacy IOCTL, it specifies the plane implicitly used by the SETCURSOR
924 	 * and SETCURSOR2 IOCTLs. It does not have any significance
925 	 * beyond that.
926 	 */
927 	struct drm_plane *cursor;
928 
929 	/**
930 	 * @index: Position inside the mode_config.list, can be used as an array
931 	 * index. It is invariant over the lifetime of the CRTC.
932 	 */
933 	unsigned index;
934 
935 	/**
936 	 * @cursor_x: Current x position of the cursor, used for universal
937 	 * cursor planes because the SETCURSOR IOCTL only can update the
938 	 * framebuffer without supplying the coordinates. Drivers should not use
939 	 * this directly, atomic drivers should look at &drm_plane_state.crtc_x
940 	 * of the cursor plane instead.
941 	 */
942 	int cursor_x;
943 	/**
944 	 * @cursor_y: Current y position of the cursor, used for universal
945 	 * cursor planes because the SETCURSOR IOCTL only can update the
946 	 * framebuffer without supplying the coordinates. Drivers should not use
947 	 * this directly, atomic drivers should look at &drm_plane_state.crtc_y
948 	 * of the cursor plane instead.
949 	 */
950 	int cursor_y;
951 
952 	/**
953 	 * @enabled:
954 	 *
955 	 * Is this CRTC enabled? Should only be used by legacy drivers, atomic
956 	 * drivers should instead consult &drm_crtc_state.enable and
957 	 * &drm_crtc_state.active. Atomic drivers can update this by calling
958 	 * drm_atomic_helper_update_legacy_modeset_state().
959 	 */
960 	bool enabled;
961 
962 	/**
963 	 * @mode:
964 	 *
965 	 * Current mode timings. Should only be used by legacy drivers, atomic
966 	 * drivers should instead consult &drm_crtc_state.mode. Atomic drivers
967 	 * can update this by calling
968 	 * drm_atomic_helper_update_legacy_modeset_state().
969 	 */
970 	struct drm_display_mode mode;
971 
972 	/**
973 	 * @hwmode:
974 	 *
975 	 * Programmed mode in hw, after adjustments for encoders, crtc, panel
976 	 * scaling etc. Should only be used by legacy drivers, for high
977 	 * precision vblank timestamps in
978 	 * drm_calc_vbltimestamp_from_scanoutpos().
979 	 *
980 	 * Note that atomic drivers should not use this, but instead use
981 	 * &drm_crtc_state.adjusted_mode. And for high-precision timestamps
982 	 * drm_calc_vbltimestamp_from_scanoutpos() used &drm_vblank_crtc.hwmode,
983 	 * which is filled out by calling drm_calc_timestamping_constants().
984 	 */
985 	struct drm_display_mode hwmode;
986 
987 	/**
988 	 * @x:
989 	 * x position on screen. Should only be used by legacy drivers, atomic
990 	 * drivers should look at &drm_plane_state.crtc_x of the primary plane
991 	 * instead. Updated by calling
992 	 * drm_atomic_helper_update_legacy_modeset_state().
993 	 */
994 	int x;
995 	/**
996 	 * @y:
997 	 * y position on screen. Should only be used by legacy drivers, atomic
998 	 * drivers should look at &drm_plane_state.crtc_y of the primary plane
999 	 * instead. Updated by calling
1000 	 * drm_atomic_helper_update_legacy_modeset_state().
1001 	 */
1002 	int y;
1003 
1004 	/** @funcs: CRTC control functions */
1005 	const struct drm_crtc_funcs *funcs;
1006 
1007 	/**
1008 	 * @gamma_size: Size of legacy gamma ramp reported to userspace. Set up
1009 	 * by calling drm_mode_crtc_set_gamma_size().
1010 	 */
1011 	uint32_t gamma_size;
1012 
1013 	/**
1014 	 * @gamma_store: Gamma ramp values used by the legacy SETGAMMA and
1015 	 * GETGAMMA IOCTls. Set up by calling drm_mode_crtc_set_gamma_size().
1016 	 */
1017 	uint16_t *gamma_store;
1018 
1019 	/** @helper_private: mid-layer private data */
1020 	const struct drm_crtc_helper_funcs *helper_private;
1021 
1022 	/** @properties: property tracking for this CRTC */
1023 	struct drm_object_properties properties;
1024 
1025 	/**
1026 	 * @state:
1027 	 *
1028 	 * Current atomic state for this CRTC.
1029 	 *
1030 	 * This is protected by @mutex. Note that nonblocking atomic commits
1031 	 * access the current CRTC state without taking locks. Either by going
1032 	 * through the &struct drm_atomic_state pointers, see
1033 	 * for_each_oldnew_crtc_in_state(), for_each_old_crtc_in_state() and
1034 	 * for_each_new_crtc_in_state(). Or through careful ordering of atomic
1035 	 * commit operations as implemented in the atomic helpers, see
1036 	 * &struct drm_crtc_commit.
1037 	 */
1038 	struct drm_crtc_state *state;
1039 
1040 	/**
1041 	 * @commit_list:
1042 	 *
1043 	 * List of &drm_crtc_commit structures tracking pending commits.
1044 	 * Protected by @commit_lock. This list holds its own full reference,
1045 	 * as does the ongoing commit.
1046 	 *
1047 	 * "Note that the commit for a state change is also tracked in
1048 	 * &drm_crtc_state.commit. For accessing the immediately preceding
1049 	 * commit in an atomic update it is recommended to just use that
1050 	 * pointer in the old CRTC state, since accessing that doesn't need
1051 	 * any locking or list-walking. @commit_list should only be used to
1052 	 * stall for framebuffer cleanup that's signalled through
1053 	 * &drm_crtc_commit.cleanup_done."
1054 	 */
1055 	struct list_head commit_list;
1056 
1057 	/**
1058 	 * @commit_lock:
1059 	 *
1060 	 * Spinlock to protect @commit_list.
1061 	 */
1062 	spinlock_t commit_lock;
1063 
1064 #ifdef CONFIG_DEBUG_FS
1065 	/**
1066 	 * @debugfs_entry:
1067 	 *
1068 	 * Debugfs directory for this CRTC.
1069 	 */
1070 	struct dentry *debugfs_entry;
1071 #endif
1072 
1073 	/**
1074 	 * @crc:
1075 	 *
1076 	 * Configuration settings of CRC capture.
1077 	 */
1078 	struct drm_crtc_crc crc;
1079 
1080 	/**
1081 	 * @fence_context:
1082 	 *
1083 	 * timeline context used for fence operations.
1084 	 */
1085 	unsigned int fence_context;
1086 
1087 	/**
1088 	 * @fence_lock:
1089 	 *
1090 	 * spinlock to protect the fences in the fence_context.
1091 	 */
1092 	spinlock_t fence_lock;
1093 	/**
1094 	 * @fence_seqno:
1095 	 *
1096 	 * Seqno variable used as monotonic counter for the fences
1097 	 * created on the CRTC's timeline.
1098 	 */
1099 	unsigned long fence_seqno;
1100 
1101 	/**
1102 	 * @timeline_name:
1103 	 *
1104 	 * The name of the CRTC's fence timeline.
1105 	 */
1106 	char timeline_name[32];
1107 
1108 	/**
1109 	 * @self_refresh_data: Holds the state for the self refresh helpers
1110 	 *
1111 	 * Initialized via drm_self_refresh_helper_init().
1112 	 */
1113 	struct drm_self_refresh_data *self_refresh_data;
1114 };
1115 
1116 /**
1117  * struct drm_mode_set - new values for a CRTC config change
1118  * @fb: framebuffer to use for new config
1119  * @crtc: CRTC whose configuration we're about to change
1120  * @mode: mode timings to use
1121  * @x: position of this CRTC relative to @fb
1122  * @y: position of this CRTC relative to @fb
1123  * @connectors: array of connectors to drive with this CRTC if possible
1124  * @num_connectors: size of @connectors array
1125  *
1126  * This represents a modeset configuration for the legacy SETCRTC ioctl and is
1127  * also used internally. Atomic drivers instead use &drm_atomic_state.
1128  */
1129 struct drm_mode_set {
1130 	struct drm_framebuffer *fb;
1131 	struct drm_crtc *crtc;
1132 	struct drm_display_mode *mode;
1133 
1134 	uint32_t x;
1135 	uint32_t y;
1136 
1137 	struct drm_connector **connectors;
1138 	size_t num_connectors;
1139 };
1140 
1141 #define obj_to_crtc(x) container_of(x, struct drm_crtc, base)
1142 
1143 __printf(6, 7)
1144 int drm_crtc_init_with_planes(struct drm_device *dev,
1145 			      struct drm_crtc *crtc,
1146 			      struct drm_plane *primary,
1147 			      struct drm_plane *cursor,
1148 			      const struct drm_crtc_funcs *funcs,
1149 			      const char *name, ...);
1150 void drm_crtc_cleanup(struct drm_crtc *crtc);
1151 
1152 /**
1153  * drm_crtc_index - find the index of a registered CRTC
1154  * @crtc: CRTC to find index for
1155  *
1156  * Given a registered CRTC, return the index of that CRTC within a DRM
1157  * device's list of CRTCs.
1158  */
1159 static inline unsigned int drm_crtc_index(const struct drm_crtc *crtc)
1160 {
1161 	return crtc->index;
1162 }
1163 
1164 /**
1165  * drm_crtc_mask - find the mask of a registered CRTC
1166  * @crtc: CRTC to find mask for
1167  *
1168  * Given a registered CRTC, return the mask bit of that CRTC for the
1169  * &drm_encoder.possible_crtcs and &drm_plane.possible_crtcs fields.
1170  */
1171 static inline uint32_t drm_crtc_mask(const struct drm_crtc *crtc)
1172 {
1173 	return 1 << drm_crtc_index(crtc);
1174 }
1175 
1176 int drm_mode_set_config_internal(struct drm_mode_set *set);
1177 struct drm_crtc *drm_crtc_from_index(struct drm_device *dev, int idx);
1178 
1179 /**
1180  * drm_crtc_find - look up a CRTC object from its ID
1181  * @dev: DRM device
1182  * @file_priv: drm file to check for lease against.
1183  * @id: &drm_mode_object ID
1184  *
1185  * This can be used to look up a CRTC from its userspace ID. Only used by
1186  * drivers for legacy IOCTLs and interface, nowadays extensions to the KMS
1187  * userspace interface should be done using &drm_property.
1188  */
1189 static inline struct drm_crtc *drm_crtc_find(struct drm_device *dev,
1190 		struct drm_file *file_priv,
1191 		uint32_t id)
1192 {
1193 	struct drm_mode_object *mo;
1194 	mo = drm_mode_object_find(dev, file_priv, id, DRM_MODE_OBJECT_CRTC);
1195 	return mo ? obj_to_crtc(mo) : NULL;
1196 }
1197 
1198 /**
1199  * drm_for_each_crtc - iterate over all CRTCs
1200  * @crtc: a &struct drm_crtc as the loop cursor
1201  * @dev: the &struct drm_device
1202  *
1203  * Iterate over all CRTCs of @dev.
1204  */
1205 #define drm_for_each_crtc(crtc, dev) \
1206 	list_for_each_entry(crtc, &(dev)->mode_config.crtc_list, head)
1207 
1208 #endif /* __DRM_CRTC_H__ */
1209