xref: /linux/include/drm/drm_crtc.h (revision 9a379e77033f02c4a071891afdf0f0a01eff8ccb)
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_property.h>
43 #include <drm/drm_bridge.h>
44 #include <drm/drm_edid.h>
45 #include <drm/drm_plane.h>
46 #include <drm/drm_blend.h>
47 #include <drm/drm_color_mgmt.h>
48 #include <drm/drm_debugfs_crc.h>
49 #include <drm/drm_mode_config.h>
50 
51 struct drm_device;
52 struct drm_mode_set;
53 struct drm_file;
54 struct drm_clip_rect;
55 struct drm_printer;
56 struct device_node;
57 struct dma_fence;
58 struct edid;
59 
60 static inline int64_t U642I64(uint64_t val)
61 {
62 	return (int64_t)*((int64_t *)&val);
63 }
64 static inline uint64_t I642U64(int64_t val)
65 {
66 	return (uint64_t)*((uint64_t *)&val);
67 }
68 
69 struct drm_crtc;
70 struct drm_pending_vblank_event;
71 struct drm_plane;
72 struct drm_bridge;
73 struct drm_atomic_state;
74 
75 struct drm_crtc_helper_funcs;
76 struct drm_plane_helper_funcs;
77 
78 /**
79  * struct drm_crtc_state - mutable CRTC state
80  * @crtc: backpointer to the CRTC
81  * @enable: whether the CRTC should be enabled, gates all other state
82  * @active: whether the CRTC is actively displaying (used for DPMS)
83  * @planes_changed: planes on this crtc are updated
84  * @mode_changed: @mode or @enable has been changed
85  * @active_changed: @active has been toggled.
86  * @connectors_changed: connectors to this crtc have been updated
87  * @zpos_changed: zpos values of planes on this crtc have been updated
88  * @color_mgmt_changed: color management properties have changed (degamma or
89  *	gamma LUT or CSC matrix)
90  * @plane_mask: bitmask of (1 << drm_plane_index(plane)) of attached planes
91  * @connector_mask: bitmask of (1 << drm_connector_index(connector)) of attached connectors
92  * @encoder_mask: bitmask of (1 << drm_encoder_index(encoder)) of attached encoders
93  * @mode_blob: &drm_property_blob for @mode
94  * @state: backpointer to global drm_atomic_state
95  *
96  * Note that the distinction between @enable and @active is rather subtile:
97  * Flipping @active while @enable is set without changing anything else may
98  * never return in a failure from the &drm_mode_config_funcs.atomic_check
99  * callback. Userspace assumes that a DPMS On will always succeed. In other
100  * words: @enable controls resource assignment, @active controls the actual
101  * hardware state.
102  *
103  * The three booleans active_changed, connectors_changed and mode_changed are
104  * intended to indicate whether a full modeset is needed, rather than strictly
105  * describing what has changed in a commit.
106  * See also: drm_atomic_crtc_needs_modeset()
107  */
108 struct drm_crtc_state {
109 	struct drm_crtc *crtc;
110 
111 	bool enable;
112 	bool active;
113 
114 	/* computed state bits used by helpers and drivers */
115 	bool planes_changed : 1;
116 	bool mode_changed : 1;
117 	bool active_changed : 1;
118 	bool connectors_changed : 1;
119 	bool zpos_changed : 1;
120 	bool color_mgmt_changed : 1;
121 
122 	/* attached planes bitmask:
123 	 * WARNING: transitional helpers do not maintain plane_mask so
124 	 * drivers not converted over to atomic helpers should not rely
125 	 * on plane_mask being accurate!
126 	 */
127 	u32 plane_mask;
128 
129 	u32 connector_mask;
130 	u32 encoder_mask;
131 
132 	/**
133 	 * @adjusted_mode:
134 	 *
135 	 * Internal display timings which can be used by the driver to handle
136 	 * differences between the mode requested by userspace in @mode and what
137 	 * is actually programmed into the hardware. It is purely driver
138 	 * implementation defined what exactly this adjusted mode means. Usually
139 	 * it is used to store the hardware display timings used between the
140 	 * CRTC and encoder blocks.
141 	 */
142 	struct drm_display_mode adjusted_mode;
143 
144 	/**
145 	 * @mode:
146 	 *
147 	 * Display timings requested by userspace. The driver should try to
148 	 * match the refresh rate as close as possible (but note that it's
149 	 * undefined what exactly is close enough, e.g. some of the HDMI modes
150 	 * only differ in less than 1% of the refresh rate). The active width
151 	 * and height as observed by userspace for positioning planes must match
152 	 * exactly.
153 	 *
154 	 * For external connectors where the sink isn't fixed (like with a
155 	 * built-in panel), this mode here should match the physical mode on the
156 	 * wire to the last details (i.e. including sync polarities and
157 	 * everything).
158 	 */
159 	struct drm_display_mode mode;
160 
161 	/* blob property to expose current mode to atomic userspace */
162 	struct drm_property_blob *mode_blob;
163 
164 	/**
165 	 * @degamma_lut:
166 	 *
167 	 * Lookup table for converting framebuffer pixel data before apply the
168 	 * color conversion matrix @ctm. See drm_crtc_enable_color_mgmt(). The
169 	 * blob (if not NULL) is an array of &struct drm_color_lut.
170 	 */
171 	struct drm_property_blob *degamma_lut;
172 
173 	/**
174 	 * @ctm:
175 	 *
176 	 * Color transformation matrix. See drm_crtc_enable_color_mgmt(). The
177 	 * blob (if not NULL) is a &struct drm_color_ctm.
178 	 */
179 	struct drm_property_blob *ctm;
180 
181 	/**
182 	 * @gamma_lut:
183 	 *
184 	 * Lookup table for converting pixel data after the color conversion
185 	 * matrix @ctm.  See drm_crtc_enable_color_mgmt(). The blob (if not
186 	 * NULL) is an array of &struct drm_color_lut.
187 	 */
188 	struct drm_property_blob *gamma_lut;
189 
190 	/**
191 	 * @target_vblank:
192 	 *
193 	 * Target vertical blank period when a page flip
194 	 * should take effect.
195 	 */
196 	u32 target_vblank;
197 
198 	/**
199 	 * @pageflip_flags:
200 	 *
201 	 * DRM_MODE_PAGE_FLIP_* flags, as passed to the page flip ioctl.
202 	 * Zero in any other case.
203 	 */
204 	u32 pageflip_flags;
205 
206 	/**
207 	 * @event:
208 	 *
209 	 * Optional pointer to a DRM event to signal upon completion of the
210 	 * state update. The driver must send out the event when the atomic
211 	 * commit operation completes. There are two cases:
212 	 *
213 	 *  - The event is for a CRTC which is being disabled through this
214 	 *    atomic commit. In that case the event can be send out any time
215 	 *    after the hardware has stopped scanning out the current
216 	 *    framebuffers. It should contain the timestamp and counter for the
217 	 *    last vblank before the display pipeline was shut off. The simplest
218 	 *    way to achieve that is calling drm_crtc_send_vblank_event()
219 	 *    somewhen after drm_crtc_vblank_off() has been called.
220 	 *
221 	 *  - For a CRTC which is enabled at the end of the commit (even when it
222 	 *    undergoes an full modeset) the vblank timestamp and counter must
223 	 *    be for the vblank right before the first frame that scans out the
224 	 *    new set of buffers. Again the event can only be sent out after the
225 	 *    hardware has stopped scanning out the old buffers.
226 	 *
227 	 *  - Events for disabled CRTCs are not allowed, and drivers can ignore
228 	 *    that case.
229 	 *
230 	 * This can be handled by the drm_crtc_send_vblank_event() function,
231 	 * which the driver should call on the provided event upon completion of
232 	 * the atomic commit. Note that if the driver supports vblank signalling
233 	 * and timestamping the vblank counters and timestamps must agree with
234 	 * the ones returned from page flip events. With the current vblank
235 	 * helper infrastructure this can be achieved by holding a vblank
236 	 * reference while the page flip is pending, acquired through
237 	 * drm_crtc_vblank_get() and released with drm_crtc_vblank_put().
238 	 * Drivers are free to implement their own vblank counter and timestamp
239 	 * tracking though, e.g. if they have accurate timestamp registers in
240 	 * hardware.
241 	 *
242 	 * For hardware which supports some means to synchronize vblank
243 	 * interrupt delivery with committing display state there's also
244 	 * drm_crtc_arm_vblank_event(). See the documentation of that function
245 	 * for a detailed discussion of the constraints it needs to be used
246 	 * safely.
247 	 *
248 	 * If the device can't notify of flip completion in a race-free way
249 	 * at all, then the event should be armed just after the page flip is
250 	 * committed. In the worst case the driver will send the event to
251 	 * userspace one frame too late. This doesn't allow for a real atomic
252 	 * update, but it should avoid tearing.
253 	 */
254 	struct drm_pending_vblank_event *event;
255 
256 	/**
257 	 * @commit:
258 	 *
259 	 * This tracks how the commit for this update proceeds through the
260 	 * various phases. This is never cleared, except when we destroy the
261 	 * state, so that subsequent commits can synchronize with previous ones.
262 	 */
263 	struct drm_crtc_commit *commit;
264 
265 	struct drm_atomic_state *state;
266 };
267 
268 /**
269  * struct drm_crtc_funcs - control CRTCs for a given device
270  *
271  * The drm_crtc_funcs structure is the central CRTC management structure
272  * in the DRM.  Each CRTC controls one or more connectors (note that the name
273  * CRTC is simply historical, a CRTC may control LVDS, VGA, DVI, TV out, etc.
274  * connectors, not just CRTs).
275  *
276  * Each driver is responsible for filling out this structure at startup time,
277  * in addition to providing other modesetting features, like i2c and DDC
278  * bus accessors.
279  */
280 struct drm_crtc_funcs {
281 	/**
282 	 * @reset:
283 	 *
284 	 * Reset CRTC hardware and software state to off. This function isn't
285 	 * called by the core directly, only through drm_mode_config_reset().
286 	 * It's not a helper hook only for historical reasons.
287 	 *
288 	 * Atomic drivers can use drm_atomic_helper_crtc_reset() to reset
289 	 * atomic state using this hook.
290 	 */
291 	void (*reset)(struct drm_crtc *crtc);
292 
293 	/**
294 	 * @cursor_set:
295 	 *
296 	 * Update the cursor image. The cursor position is relative to the CRTC
297 	 * and can be partially or fully outside of the visible area.
298 	 *
299 	 * Note that contrary to all other KMS functions the legacy cursor entry
300 	 * points don't take a framebuffer object, but instead take directly a
301 	 * raw buffer object id from the driver's buffer manager (which is
302 	 * either GEM or TTM for current drivers).
303 	 *
304 	 * This entry point is deprecated, drivers should instead implement
305 	 * universal plane support and register a proper cursor plane using
306 	 * drm_crtc_init_with_planes().
307 	 *
308 	 * This callback is optional
309 	 *
310 	 * RETURNS:
311 	 *
312 	 * 0 on success or a negative error code on failure.
313 	 */
314 	int (*cursor_set)(struct drm_crtc *crtc, struct drm_file *file_priv,
315 			  uint32_t handle, uint32_t width, uint32_t height);
316 
317 	/**
318 	 * @cursor_set2:
319 	 *
320 	 * Update the cursor image, including hotspot information. The hotspot
321 	 * must not affect the cursor position in CRTC coordinates, but is only
322 	 * meant as a hint for virtualized display hardware to coordinate the
323 	 * guests and hosts cursor position. The cursor hotspot is relative to
324 	 * the cursor image. Otherwise this works exactly like @cursor_set.
325 	 *
326 	 * This entry point is deprecated, drivers should instead implement
327 	 * universal plane support and register a proper cursor plane using
328 	 * drm_crtc_init_with_planes().
329 	 *
330 	 * This callback is optional.
331 	 *
332 	 * RETURNS:
333 	 *
334 	 * 0 on success or a negative error code on failure.
335 	 */
336 	int (*cursor_set2)(struct drm_crtc *crtc, struct drm_file *file_priv,
337 			   uint32_t handle, uint32_t width, uint32_t height,
338 			   int32_t hot_x, int32_t hot_y);
339 
340 	/**
341 	 * @cursor_move:
342 	 *
343 	 * Update the cursor position. The cursor does not need to be visible
344 	 * when this hook is called.
345 	 *
346 	 * This entry point is deprecated, drivers should instead implement
347 	 * universal plane support and register a proper cursor plane using
348 	 * drm_crtc_init_with_planes().
349 	 *
350 	 * This callback is optional.
351 	 *
352 	 * RETURNS:
353 	 *
354 	 * 0 on success or a negative error code on failure.
355 	 */
356 	int (*cursor_move)(struct drm_crtc *crtc, int x, int y);
357 
358 	/**
359 	 * @gamma_set:
360 	 *
361 	 * Set gamma on the CRTC.
362 	 *
363 	 * This callback is optional.
364 	 *
365 	 * Atomic drivers who want to support gamma tables should implement the
366 	 * atomic color management support, enabled by calling
367 	 * drm_crtc_enable_color_mgmt(), which then supports the legacy gamma
368 	 * interface through the drm_atomic_helper_legacy_gamma_set()
369 	 * compatibility implementation.
370 	 */
371 	int (*gamma_set)(struct drm_crtc *crtc, u16 *r, u16 *g, u16 *b,
372 			 uint32_t size,
373 			 struct drm_modeset_acquire_ctx *ctx);
374 
375 	/**
376 	 * @destroy:
377 	 *
378 	 * Clean up plane resources. This is only called at driver unload time
379 	 * through drm_mode_config_cleanup() since a CRTC cannot be hotplugged
380 	 * in DRM.
381 	 */
382 	void (*destroy)(struct drm_crtc *crtc);
383 
384 	/**
385 	 * @set_config:
386 	 *
387 	 * This is the main legacy entry point to change the modeset state on a
388 	 * CRTC. All the details of the desired configuration are passed in a
389 	 * &struct drm_mode_set - see there for details.
390 	 *
391 	 * Drivers implementing atomic modeset should use
392 	 * drm_atomic_helper_set_config() to implement this hook.
393 	 *
394 	 * RETURNS:
395 	 *
396 	 * 0 on success or a negative error code on failure.
397 	 */
398 	int (*set_config)(struct drm_mode_set *set,
399 			  struct drm_modeset_acquire_ctx *ctx);
400 
401 	/**
402 	 * @page_flip:
403 	 *
404 	 * Legacy entry point to schedule a flip to the given framebuffer.
405 	 *
406 	 * Page flipping is a synchronization mechanism that replaces the frame
407 	 * buffer being scanned out by the CRTC with a new frame buffer during
408 	 * vertical blanking, avoiding tearing (except when requested otherwise
409 	 * through the DRM_MODE_PAGE_FLIP_ASYNC flag). When an application
410 	 * requests a page flip the DRM core verifies that the new frame buffer
411 	 * is large enough to be scanned out by the CRTC in the currently
412 	 * configured mode and then calls this hook with a pointer to the new
413 	 * frame buffer.
414 	 *
415 	 * The driver must wait for any pending rendering to the new framebuffer
416 	 * to complete before executing the flip. It should also wait for any
417 	 * pending rendering from other drivers if the underlying buffer is a
418 	 * shared dma-buf.
419 	 *
420 	 * An application can request to be notified when the page flip has
421 	 * completed. The drm core will supply a &struct drm_event in the event
422 	 * parameter in this case. This can be handled by the
423 	 * drm_crtc_send_vblank_event() function, which the driver should call on
424 	 * the provided event upon completion of the flip. Note that if
425 	 * the driver supports vblank signalling and timestamping the vblank
426 	 * counters and timestamps must agree with the ones returned from page
427 	 * flip events. With the current vblank helper infrastructure this can
428 	 * be achieved by holding a vblank reference while the page flip is
429 	 * pending, acquired through drm_crtc_vblank_get() and released with
430 	 * drm_crtc_vblank_put(). Drivers are free to implement their own vblank
431 	 * counter and timestamp tracking though, e.g. if they have accurate
432 	 * timestamp registers in hardware.
433 	 *
434 	 * This callback is optional.
435 	 *
436 	 * NOTE:
437 	 *
438 	 * Very early versions of the KMS ABI mandated that the driver must
439 	 * block (but not reject) any rendering to the old framebuffer until the
440 	 * flip operation has completed and the old framebuffer is no longer
441 	 * visible. This requirement has been lifted, and userspace is instead
442 	 * expected to request delivery of an event and wait with recycling old
443 	 * buffers until such has been received.
444 	 *
445 	 * RETURNS:
446 	 *
447 	 * 0 on success or a negative error code on failure. Note that if a
448 	 * page flip operation is already pending the callback should return
449 	 * -EBUSY. Pageflips on a disabled CRTC (either by setting a NULL mode
450 	 * or just runtime disabled through DPMS respectively the new atomic
451 	 * "ACTIVE" state) should result in an -EINVAL error code. Note that
452 	 * drm_atomic_helper_page_flip() checks this already for atomic drivers.
453 	 */
454 	int (*page_flip)(struct drm_crtc *crtc,
455 			 struct drm_framebuffer *fb,
456 			 struct drm_pending_vblank_event *event,
457 			 uint32_t flags,
458 			 struct drm_modeset_acquire_ctx *ctx);
459 
460 	/**
461 	 * @page_flip_target:
462 	 *
463 	 * Same as @page_flip but with an additional parameter specifying the
464 	 * absolute target vertical blank period (as reported by
465 	 * drm_crtc_vblank_count()) when the flip should take effect.
466 	 *
467 	 * Note that the core code calls drm_crtc_vblank_get before this entry
468 	 * point, and will call drm_crtc_vblank_put if this entry point returns
469 	 * any non-0 error code. It's the driver's responsibility to call
470 	 * drm_crtc_vblank_put after this entry point returns 0, typically when
471 	 * the flip completes.
472 	 */
473 	int (*page_flip_target)(struct drm_crtc *crtc,
474 				struct drm_framebuffer *fb,
475 				struct drm_pending_vblank_event *event,
476 				uint32_t flags, uint32_t target,
477 				struct drm_modeset_acquire_ctx *ctx);
478 
479 	/**
480 	 * @set_property:
481 	 *
482 	 * This is the legacy entry point to update a property attached to the
483 	 * CRTC.
484 	 *
485 	 * This callback is optional if the driver does not support any legacy
486 	 * driver-private properties. For atomic drivers it is not used because
487 	 * property handling is done entirely in the DRM core.
488 	 *
489 	 * RETURNS:
490 	 *
491 	 * 0 on success or a negative error code on failure.
492 	 */
493 	int (*set_property)(struct drm_crtc *crtc,
494 			    struct drm_property *property, uint64_t val);
495 
496 	/**
497 	 * @atomic_duplicate_state:
498 	 *
499 	 * Duplicate the current atomic state for this CRTC and return it.
500 	 * The core and helpers guarantee that any atomic state duplicated with
501 	 * this hook and still owned by the caller (i.e. not transferred to the
502 	 * driver by calling &drm_mode_config_funcs.atomic_commit) will be
503 	 * cleaned up by calling the @atomic_destroy_state hook in this
504 	 * structure.
505 	 *
506 	 * Atomic drivers which don't subclass &struct drm_crtc_state should use
507 	 * drm_atomic_helper_crtc_duplicate_state(). Drivers that subclass the
508 	 * state structure to extend it with driver-private state should use
509 	 * __drm_atomic_helper_crtc_duplicate_state() to make sure shared state is
510 	 * duplicated in a consistent fashion across drivers.
511 	 *
512 	 * It is an error to call this hook before &drm_crtc.state has been
513 	 * initialized correctly.
514 	 *
515 	 * NOTE:
516 	 *
517 	 * If the duplicate state references refcounted resources this hook must
518 	 * acquire a reference for each of them. The driver must release these
519 	 * references again in @atomic_destroy_state.
520 	 *
521 	 * RETURNS:
522 	 *
523 	 * Duplicated atomic state or NULL when the allocation failed.
524 	 */
525 	struct drm_crtc_state *(*atomic_duplicate_state)(struct drm_crtc *crtc);
526 
527 	/**
528 	 * @atomic_destroy_state:
529 	 *
530 	 * Destroy a state duplicated with @atomic_duplicate_state and release
531 	 * or unreference all resources it references
532 	 */
533 	void (*atomic_destroy_state)(struct drm_crtc *crtc,
534 				     struct drm_crtc_state *state);
535 
536 	/**
537 	 * @atomic_set_property:
538 	 *
539 	 * Decode a driver-private property value and store the decoded value
540 	 * into the passed-in state structure. Since the atomic core decodes all
541 	 * standardized properties (even for extensions beyond the core set of
542 	 * properties which might not be implemented by all drivers) this
543 	 * requires drivers to subclass the state structure.
544 	 *
545 	 * Such driver-private properties should really only be implemented for
546 	 * truly hardware/vendor specific state. Instead it is preferred to
547 	 * standardize atomic extension and decode the properties used to expose
548 	 * such an extension in the core.
549 	 *
550 	 * Do not call this function directly, use
551 	 * drm_atomic_crtc_set_property() instead.
552 	 *
553 	 * This callback is optional if the driver does not support any
554 	 * driver-private atomic properties.
555 	 *
556 	 * NOTE:
557 	 *
558 	 * This function is called in the state assembly phase of atomic
559 	 * modesets, which can be aborted for any reason (including on
560 	 * userspace's request to just check whether a configuration would be
561 	 * possible). Drivers MUST NOT touch any persistent state (hardware or
562 	 * software) or data structures except the passed in @state parameter.
563 	 *
564 	 * Also since userspace controls in which order properties are set this
565 	 * function must not do any input validation (since the state update is
566 	 * incomplete and hence likely inconsistent). Instead any such input
567 	 * validation must be done in the various atomic_check callbacks.
568 	 *
569 	 * RETURNS:
570 	 *
571 	 * 0 if the property has been found, -EINVAL if the property isn't
572 	 * implemented by the driver (which should never happen, the core only
573 	 * asks for properties attached to this CRTC). No other validation is
574 	 * allowed by the driver. The core already checks that the property
575 	 * value is within the range (integer, valid enum value, ...) the driver
576 	 * set when registering the property.
577 	 */
578 	int (*atomic_set_property)(struct drm_crtc *crtc,
579 				   struct drm_crtc_state *state,
580 				   struct drm_property *property,
581 				   uint64_t val);
582 	/**
583 	 * @atomic_get_property:
584 	 *
585 	 * Reads out the decoded driver-private property. This is used to
586 	 * implement the GETCRTC IOCTL.
587 	 *
588 	 * Do not call this function directly, use
589 	 * drm_atomic_crtc_get_property() instead.
590 	 *
591 	 * This callback is optional if the driver does not support any
592 	 * driver-private atomic properties.
593 	 *
594 	 * RETURNS:
595 	 *
596 	 * 0 on success, -EINVAL if the property isn't implemented by the
597 	 * driver (which should never happen, the core only asks for
598 	 * properties attached to this CRTC).
599 	 */
600 	int (*atomic_get_property)(struct drm_crtc *crtc,
601 				   const struct drm_crtc_state *state,
602 				   struct drm_property *property,
603 				   uint64_t *val);
604 
605 	/**
606 	 * @late_register:
607 	 *
608 	 * This optional hook can be used to register additional userspace
609 	 * interfaces attached to the crtc like debugfs interfaces.
610 	 * It is called late in the driver load sequence from drm_dev_register().
611 	 * Everything added from this callback should be unregistered in
612 	 * the early_unregister callback.
613 	 *
614 	 * Returns:
615 	 *
616 	 * 0 on success, or a negative error code on failure.
617 	 */
618 	int (*late_register)(struct drm_crtc *crtc);
619 
620 	/**
621 	 * @early_unregister:
622 	 *
623 	 * This optional hook should be used to unregister the additional
624 	 * userspace interfaces attached to the crtc from
625 	 * @late_register. It is called from drm_dev_unregister(),
626 	 * early in the driver unload sequence to disable userspace access
627 	 * before data structures are torndown.
628 	 */
629 	void (*early_unregister)(struct drm_crtc *crtc);
630 
631 	/**
632 	 * @set_crc_source:
633 	 *
634 	 * Changes the source of CRC checksums of frames at the request of
635 	 * userspace, typically for testing purposes. The sources available are
636 	 * specific of each driver and a %NULL value indicates that CRC
637 	 * generation is to be switched off.
638 	 *
639 	 * When CRC generation is enabled, the driver should call
640 	 * drm_crtc_add_crc_entry() at each frame, providing any information
641 	 * that characterizes the frame contents in the crcN arguments, as
642 	 * provided from the configured source. Drivers must accept an "auto"
643 	 * source name that will select a default source for this CRTC.
644 	 *
645 	 * Note that "auto" can depend upon the current modeset configuration,
646 	 * e.g. it could pick an encoder or output specific CRC sampling point.
647 	 *
648 	 * This callback is optional if the driver does not support any CRC
649 	 * generation functionality.
650 	 *
651 	 * RETURNS:
652 	 *
653 	 * 0 on success or a negative error code on failure.
654 	 */
655 	int (*set_crc_source)(struct drm_crtc *crtc, const char *source,
656 			      size_t *values_cnt);
657 
658 	/**
659 	 * @atomic_print_state:
660 	 *
661 	 * If driver subclasses &struct drm_crtc_state, it should implement
662 	 * this optional hook for printing additional driver specific state.
663 	 *
664 	 * Do not call this directly, use drm_atomic_crtc_print_state()
665 	 * instead.
666 	 */
667 	void (*atomic_print_state)(struct drm_printer *p,
668 				   const struct drm_crtc_state *state);
669 
670 	/**
671 	 * @get_vblank_counter:
672 	 *
673 	 * Driver callback for fetching a raw hardware vblank counter for the
674 	 * CRTC. It's meant to be used by new drivers as the replacement of
675 	 * &drm_driver.get_vblank_counter hook.
676 	 *
677 	 * This callback is optional. If a device doesn't have a hardware
678 	 * counter, the driver can simply leave the hook as NULL. The DRM core
679 	 * will account for missed vblank events while interrupts where disabled
680 	 * based on system timestamps.
681 	 *
682 	 * Wraparound handling and loss of events due to modesetting is dealt
683 	 * with in the DRM core code, as long as drivers call
684 	 * drm_crtc_vblank_off() and drm_crtc_vblank_on() when disabling or
685 	 * enabling a CRTC.
686 	 *
687 	 * See also &drm_device.vblank_disable_immediate and
688 	 * &drm_device.max_vblank_count.
689 	 *
690 	 * Returns:
691 	 *
692 	 * Raw vblank counter value.
693 	 */
694 	u32 (*get_vblank_counter)(struct drm_crtc *crtc);
695 
696 	/**
697 	 * @enable_vblank:
698 	 *
699 	 * Enable vblank interrupts for the CRTC. It's meant to be used by
700 	 * new drivers as the replacement of &drm_driver.enable_vblank hook.
701 	 *
702 	 * Returns:
703 	 *
704 	 * Zero on success, appropriate errno if the vblank interrupt cannot
705 	 * be enabled.
706 	 */
707 	int (*enable_vblank)(struct drm_crtc *crtc);
708 
709 	/**
710 	 * @disable_vblank:
711 	 *
712 	 * Disable vblank interrupts for the CRTC. It's meant to be used by
713 	 * new drivers as the replacement of &drm_driver.disable_vblank hook.
714 	 */
715 	void (*disable_vblank)(struct drm_crtc *crtc);
716 };
717 
718 /**
719  * struct drm_crtc - central CRTC control structure
720  * @dev: parent DRM device
721  * @port: OF node used by drm_of_find_possible_crtcs()
722  * @head: list management
723  * @name: human readable name, can be overwritten by the driver
724  * @mutex: per-CRTC locking
725  * @base: base KMS object for ID tracking etc.
726  * @primary: primary plane for this CRTC
727  * @cursor: cursor plane for this CRTC
728  * @cursor_x: current x position of the cursor, used for universal cursor planes
729  * @cursor_y: current y position of the cursor, used for universal cursor planes
730  * @enabled: is this CRTC enabled?
731  * @mode: current mode timings
732  * @hwmode: mode timings as programmed to hw regs
733  * @x: x position on screen
734  * @y: y position on screen
735  * @funcs: CRTC control functions
736  * @gamma_size: size of gamma ramp
737  * @gamma_store: gamma ramp values
738  * @helper_private: mid-layer private data
739  * @properties: property tracking for this CRTC
740  *
741  * Each CRTC may have one or more connectors associated with it.  This structure
742  * allows the CRTC to be controlled.
743  */
744 struct drm_crtc {
745 	struct drm_device *dev;
746 	struct device_node *port;
747 	struct list_head head;
748 
749 	char *name;
750 
751 	/**
752 	 * @mutex:
753 	 *
754 	 * This provides a read lock for the overall CRTC state (mode, dpms
755 	 * state, ...) and a write lock for everything which can be update
756 	 * without a full modeset (fb, cursor data, CRTC properties ...). A full
757 	 * modeset also need to grab &drm_mode_config.connection_mutex.
758 	 *
759 	 * For atomic drivers specifically this protects @state.
760 	 */
761 	struct drm_modeset_lock mutex;
762 
763 	struct drm_mode_object base;
764 
765 	/* primary and cursor planes for CRTC */
766 	struct drm_plane *primary;
767 	struct drm_plane *cursor;
768 
769 	/**
770 	 * @index: Position inside the mode_config.list, can be used as an array
771 	 * index. It is invariant over the lifetime of the CRTC.
772 	 */
773 	unsigned index;
774 
775 	/* position of cursor plane on crtc */
776 	int cursor_x;
777 	int cursor_y;
778 
779 	bool enabled;
780 
781 	/* Requested mode from modesetting. */
782 	struct drm_display_mode mode;
783 
784 	/* Programmed mode in hw, after adjustments for encoders,
785 	 * crtc, panel scaling etc. Needed for timestamping etc.
786 	 */
787 	struct drm_display_mode hwmode;
788 
789 	int x, y;
790 	const struct drm_crtc_funcs *funcs;
791 
792 	/* Legacy FB CRTC gamma size for reporting to userspace */
793 	uint32_t gamma_size;
794 	uint16_t *gamma_store;
795 
796 	/* if you are using the helper */
797 	const struct drm_crtc_helper_funcs *helper_private;
798 
799 	struct drm_object_properties properties;
800 
801 	/**
802 	 * @state:
803 	 *
804 	 * Current atomic state for this CRTC.
805 	 *
806 	 * This is protected by @mutex. Note that nonblocking atomic commits
807 	 * access the current CRTC state without taking locks. Either by going
808 	 * through the &struct drm_atomic_state pointers, see
809 	 * for_each_oldnew_crtc_in_state(), for_each_old_crtc_in_state() and
810 	 * for_each_new_crtc_in_state(). Or through careful ordering of atomic
811 	 * commit operations as implemented in the atomic helpers, see
812 	 * &struct drm_crtc_commit.
813 	 */
814 	struct drm_crtc_state *state;
815 
816 	/**
817 	 * @commit_list:
818 	 *
819 	 * List of &drm_crtc_commit structures tracking pending commits.
820 	 * Protected by @commit_lock. This list holds its own full reference,
821 	 * as does the ongoing commit.
822 	 *
823 	 * "Note that the commit for a state change is also tracked in
824 	 * &drm_crtc_state.commit. For accessing the immediately preceding
825 	 * commit in an atomic update it is recommended to just use that
826 	 * pointer in the old CRTC state, since accessing that doesn't need
827 	 * any locking or list-walking. @commit_list should only be used to
828 	 * stall for framebuffer cleanup that's signalled through
829 	 * &drm_crtc_commit.cleanup_done."
830 	 */
831 	struct list_head commit_list;
832 
833 	/**
834 	 * @commit_lock:
835 	 *
836 	 * Spinlock to protect @commit_list.
837 	 */
838 	spinlock_t commit_lock;
839 
840 #ifdef CONFIG_DEBUG_FS
841 	/**
842 	 * @debugfs_entry:
843 	 *
844 	 * Debugfs directory for this CRTC.
845 	 */
846 	struct dentry *debugfs_entry;
847 #endif
848 
849 	/**
850 	 * @crc:
851 	 *
852 	 * Configuration settings of CRC capture.
853 	 */
854 	struct drm_crtc_crc crc;
855 
856 	/**
857 	 * @fence_context:
858 	 *
859 	 * timeline context used for fence operations.
860 	 */
861 	unsigned int fence_context;
862 
863 	/**
864 	 * @fence_lock:
865 	 *
866 	 * spinlock to protect the fences in the fence_context.
867 	 */
868 
869 	spinlock_t fence_lock;
870 	/**
871 	 * @fence_seqno:
872 	 *
873 	 * Seqno variable used as monotonic counter for the fences
874 	 * created on the CRTC's timeline.
875 	 */
876 	unsigned long fence_seqno;
877 
878 	/**
879 	 * @timeline_name:
880 	 *
881 	 * The name of the CRTC's fence timeline.
882 	 */
883 	char timeline_name[32];
884 };
885 
886 /**
887  * struct drm_mode_set - new values for a CRTC config change
888  * @fb: framebuffer to use for new config
889  * @crtc: CRTC whose configuration we're about to change
890  * @mode: mode timings to use
891  * @x: position of this CRTC relative to @fb
892  * @y: position of this CRTC relative to @fb
893  * @connectors: array of connectors to drive with this CRTC if possible
894  * @num_connectors: size of @connectors array
895  *
896  * This represents a modeset configuration for the legacy SETCRTC ioctl and is
897  * also used internally. Atomic drivers instead use &drm_atomic_state.
898  */
899 struct drm_mode_set {
900 	struct drm_framebuffer *fb;
901 	struct drm_crtc *crtc;
902 	struct drm_display_mode *mode;
903 
904 	uint32_t x;
905 	uint32_t y;
906 
907 	struct drm_connector **connectors;
908 	size_t num_connectors;
909 };
910 
911 #define obj_to_crtc(x) container_of(x, struct drm_crtc, base)
912 
913 __printf(6, 7)
914 int drm_crtc_init_with_planes(struct drm_device *dev,
915 			      struct drm_crtc *crtc,
916 			      struct drm_plane *primary,
917 			      struct drm_plane *cursor,
918 			      const struct drm_crtc_funcs *funcs,
919 			      const char *name, ...);
920 void drm_crtc_cleanup(struct drm_crtc *crtc);
921 
922 /**
923  * drm_crtc_index - find the index of a registered CRTC
924  * @crtc: CRTC to find index for
925  *
926  * Given a registered CRTC, return the index of that CRTC within a DRM
927  * device's list of CRTCs.
928  */
929 static inline unsigned int drm_crtc_index(const struct drm_crtc *crtc)
930 {
931 	return crtc->index;
932 }
933 
934 /**
935  * drm_crtc_mask - find the mask of a registered CRTC
936  * @crtc: CRTC to find mask for
937  *
938  * Given a registered CRTC, return the mask bit of that CRTC for an
939  * encoder's possible_crtcs field.
940  */
941 static inline uint32_t drm_crtc_mask(const struct drm_crtc *crtc)
942 {
943 	return 1 << drm_crtc_index(crtc);
944 }
945 
946 int drm_crtc_force_disable(struct drm_crtc *crtc);
947 int drm_crtc_force_disable_all(struct drm_device *dev);
948 
949 int drm_mode_set_config_internal(struct drm_mode_set *set);
950 struct drm_crtc *drm_crtc_from_index(struct drm_device *dev, int idx);
951 
952 /**
953  * drm_crtc_find - look up a CRTC object from its ID
954  * @dev: DRM device
955  * @file_priv: drm file to check for lease against.
956  * @id: &drm_mode_object ID
957  *
958  * This can be used to look up a CRTC from its userspace ID. Only used by
959  * drivers for legacy IOCTLs and interface, nowadays extensions to the KMS
960  * userspace interface should be done using &drm_property.
961  */
962 static inline struct drm_crtc *drm_crtc_find(struct drm_device *dev,
963 		struct drm_file *file_priv,
964 		uint32_t id)
965 {
966 	struct drm_mode_object *mo;
967 	mo = drm_mode_object_find(dev, file_priv, id, DRM_MODE_OBJECT_CRTC);
968 	return mo ? obj_to_crtc(mo) : NULL;
969 }
970 
971 /**
972  * drm_for_each_crtc - iterate over all CRTCs
973  * @crtc: a &struct drm_crtc as the loop cursor
974  * @dev: the &struct drm_device
975  *
976  * Iterate over all CRTCs of @dev.
977  */
978 #define drm_for_each_crtc(crtc, dev) \
979 	list_for_each_entry(crtc, &(dev)->mode_config.crtc_list, head)
980 
981 #endif /* __DRM_CRTC_H__ */
982