xref: /openbmc/linux/include/drm/drm_crtc.h (revision 239480ab)
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  * @adjusted_mode: for use by helpers and drivers to compute adjusted mode timings
94  * @mode: current mode timings
95  * @mode_blob: &drm_property_blob for @mode
96  * @degamma_lut: Lookup table for converting framebuffer pixel data
97  *	before apply the conversion matrix
98  * @ctm: Transformation matrix
99  * @gamma_lut: Lookup table for converting pixel data after the
100  *	conversion matrix
101  * @state: backpointer to global drm_atomic_state
102  *
103  * Note that the distinction between @enable and @active is rather subtile:
104  * Flipping @active while @enable is set without changing anything else may
105  * never return in a failure from the &drm_mode_config_funcs.atomic_check
106  * callback. Userspace assumes that a DPMS On will always succeed. In other
107  * words: @enable controls resource assignment, @active controls the actual
108  * hardware state.
109  *
110  * The three booleans active_changed, connectors_changed and mode_changed are
111  * intended to indicate whether a full modeset is needed, rather than strictly
112  * describing what has changed in a commit.
113  * See also: drm_atomic_crtc_needs_modeset()
114  */
115 struct drm_crtc_state {
116 	struct drm_crtc *crtc;
117 
118 	bool enable;
119 	bool active;
120 
121 	/* computed state bits used by helpers and drivers */
122 	bool planes_changed : 1;
123 	bool mode_changed : 1;
124 	bool active_changed : 1;
125 	bool connectors_changed : 1;
126 	bool zpos_changed : 1;
127 	bool color_mgmt_changed : 1;
128 
129 	/* attached planes bitmask:
130 	 * WARNING: transitional helpers do not maintain plane_mask so
131 	 * drivers not converted over to atomic helpers should not rely
132 	 * on plane_mask being accurate!
133 	 */
134 	u32 plane_mask;
135 
136 	u32 connector_mask;
137 	u32 encoder_mask;
138 
139 	/* adjusted_mode: for use by helpers and drivers */
140 	struct drm_display_mode adjusted_mode;
141 
142 	struct drm_display_mode mode;
143 
144 	/* blob property to expose current mode to atomic userspace */
145 	struct drm_property_blob *mode_blob;
146 
147 	/* blob property to expose color management to userspace */
148 	struct drm_property_blob *degamma_lut;
149 	struct drm_property_blob *ctm;
150 	struct drm_property_blob *gamma_lut;
151 
152 	/**
153 	 * @target_vblank:
154 	 *
155 	 * Target vertical blank period when a page flip
156 	 * should take effect.
157 	 */
158 	u32 target_vblank;
159 
160 	/**
161 	 * @pageflip_flags:
162 	 *
163 	 * DRM_MODE_PAGE_FLIP_* flags, as passed to the page flip ioctl.
164 	 * Zero in any other case.
165 	 */
166 	u32 pageflip_flags;
167 
168 	/**
169 	 * @event:
170 	 *
171 	 * Optional pointer to a DRM event to signal upon completion of the
172 	 * state update. The driver must send out the event when the atomic
173 	 * commit operation completes. There are two cases:
174 	 *
175 	 *  - The event is for a CRTC which is being disabled through this
176 	 *    atomic commit. In that case the event can be send out any time
177 	 *    after the hardware has stopped scanning out the current
178 	 *    framebuffers. It should contain the timestamp and counter for the
179 	 *    last vblank before the display pipeline was shut off.
180 	 *
181 	 *  - For a CRTC which is enabled at the end of the commit (even when it
182 	 *    undergoes an full modeset) the vblank timestamp and counter must
183 	 *    be for the vblank right before the first frame that scans out the
184 	 *    new set of buffers. Again the event can only be sent out after the
185 	 *    hardware has stopped scanning out the old buffers.
186 	 *
187 	 *  - Events for disabled CRTCs are not allowed, and drivers can ignore
188 	 *    that case.
189 	 *
190 	 * This can be handled by the drm_crtc_send_vblank_event() function,
191 	 * which the driver should call on the provided event upon completion of
192 	 * the atomic commit. Note that if the driver supports vblank signalling
193 	 * and timestamping the vblank counters and timestamps must agree with
194 	 * the ones returned from page flip events. With the current vblank
195 	 * helper infrastructure this can be achieved by holding a vblank
196 	 * reference while the page flip is pending, acquired through
197 	 * drm_crtc_vblank_get() and released with drm_crtc_vblank_put().
198 	 * Drivers are free to implement their own vblank counter and timestamp
199 	 * tracking though, e.g. if they have accurate timestamp registers in
200 	 * hardware.
201 	 *
202 	 * For hardware which supports some means to synchronize vblank
203 	 * interrupt delivery with committing display state there's also
204 	 * drm_crtc_arm_vblank_event(). See the documentation of that function
205 	 * for a detailed discussion of the constraints it needs to be used
206 	 * safely.
207 	 *
208 	 * If the device can't notify of flip completion in a race-free way
209 	 * at all, then the event should be armed just after the page flip is
210 	 * committed. In the worst case the driver will send the event to
211 	 * userspace one frame too late. This doesn't allow for a real atomic
212 	 * update, but it should avoid tearing.
213 	 */
214 	struct drm_pending_vblank_event *event;
215 
216 	struct drm_atomic_state *state;
217 };
218 
219 /**
220  * struct drm_crtc_funcs - control CRTCs for a given device
221  *
222  * The drm_crtc_funcs structure is the central CRTC management structure
223  * in the DRM.  Each CRTC controls one or more connectors (note that the name
224  * CRTC is simply historical, a CRTC may control LVDS, VGA, DVI, TV out, etc.
225  * connectors, not just CRTs).
226  *
227  * Each driver is responsible for filling out this structure at startup time,
228  * in addition to providing other modesetting features, like i2c and DDC
229  * bus accessors.
230  */
231 struct drm_crtc_funcs {
232 	/**
233 	 * @reset:
234 	 *
235 	 * Reset CRTC hardware and software state to off. This function isn't
236 	 * called by the core directly, only through drm_mode_config_reset().
237 	 * It's not a helper hook only for historical reasons.
238 	 *
239 	 * Atomic drivers can use drm_atomic_helper_crtc_reset() to reset
240 	 * atomic state using this hook.
241 	 */
242 	void (*reset)(struct drm_crtc *crtc);
243 
244 	/**
245 	 * @cursor_set:
246 	 *
247 	 * Update the cursor image. The cursor position is relative to the CRTC
248 	 * and can be partially or fully outside of the visible area.
249 	 *
250 	 * Note that contrary to all other KMS functions the legacy cursor entry
251 	 * points don't take a framebuffer object, but instead take directly a
252 	 * raw buffer object id from the driver's buffer manager (which is
253 	 * either GEM or TTM for current drivers).
254 	 *
255 	 * This entry point is deprecated, drivers should instead implement
256 	 * universal plane support and register a proper cursor plane using
257 	 * drm_crtc_init_with_planes().
258 	 *
259 	 * This callback is optional
260 	 *
261 	 * RETURNS:
262 	 *
263 	 * 0 on success or a negative error code on failure.
264 	 */
265 	int (*cursor_set)(struct drm_crtc *crtc, struct drm_file *file_priv,
266 			  uint32_t handle, uint32_t width, uint32_t height);
267 
268 	/**
269 	 * @cursor_set2:
270 	 *
271 	 * Update the cursor image, including hotspot information. The hotspot
272 	 * must not affect the cursor position in CRTC coordinates, but is only
273 	 * meant as a hint for virtualized display hardware to coordinate the
274 	 * guests and hosts cursor position. The cursor hotspot is relative to
275 	 * the cursor image. Otherwise this works exactly like @cursor_set.
276 	 *
277 	 * This entry point is deprecated, drivers should instead implement
278 	 * universal plane support and register a proper cursor plane using
279 	 * drm_crtc_init_with_planes().
280 	 *
281 	 * This callback is optional.
282 	 *
283 	 * RETURNS:
284 	 *
285 	 * 0 on success or a negative error code on failure.
286 	 */
287 	int (*cursor_set2)(struct drm_crtc *crtc, struct drm_file *file_priv,
288 			   uint32_t handle, uint32_t width, uint32_t height,
289 			   int32_t hot_x, int32_t hot_y);
290 
291 	/**
292 	 * @cursor_move:
293 	 *
294 	 * Update the cursor position. The cursor does not need to be visible
295 	 * when this hook is called.
296 	 *
297 	 * This entry point is deprecated, drivers should instead implement
298 	 * universal plane support and register a proper cursor plane using
299 	 * drm_crtc_init_with_planes().
300 	 *
301 	 * This callback is optional.
302 	 *
303 	 * RETURNS:
304 	 *
305 	 * 0 on success or a negative error code on failure.
306 	 */
307 	int (*cursor_move)(struct drm_crtc *crtc, int x, int y);
308 
309 	/**
310 	 * @gamma_set:
311 	 *
312 	 * Set gamma on the CRTC.
313 	 *
314 	 * This callback is optional.
315 	 *
316 	 * NOTE:
317 	 *
318 	 * Drivers that support gamma tables and also fbdev emulation through
319 	 * the provided helper library need to take care to fill out the gamma
320 	 * hooks for both. Currently there's a bit an unfortunate duplication
321 	 * going on, which should eventually be unified to just one set of
322 	 * hooks.
323 	 */
324 	int (*gamma_set)(struct drm_crtc *crtc, u16 *r, u16 *g, u16 *b,
325 			 uint32_t size,
326 			 struct drm_modeset_acquire_ctx *ctx);
327 
328 	/**
329 	 * @destroy:
330 	 *
331 	 * Clean up plane resources. This is only called at driver unload time
332 	 * through drm_mode_config_cleanup() since a CRTC cannot be hotplugged
333 	 * in DRM.
334 	 */
335 	void (*destroy)(struct drm_crtc *crtc);
336 
337 	/**
338 	 * @set_config:
339 	 *
340 	 * This is the main legacy entry point to change the modeset state on a
341 	 * CRTC. All the details of the desired configuration are passed in a
342 	 * &struct drm_mode_set - see there for details.
343 	 *
344 	 * Drivers implementing atomic modeset should use
345 	 * drm_atomic_helper_set_config() to implement this hook.
346 	 *
347 	 * RETURNS:
348 	 *
349 	 * 0 on success or a negative error code on failure.
350 	 */
351 	int (*set_config)(struct drm_mode_set *set,
352 			  struct drm_modeset_acquire_ctx *ctx);
353 
354 	/**
355 	 * @page_flip:
356 	 *
357 	 * Legacy entry point to schedule a flip to the given framebuffer.
358 	 *
359 	 * Page flipping is a synchronization mechanism that replaces the frame
360 	 * buffer being scanned out by the CRTC with a new frame buffer during
361 	 * vertical blanking, avoiding tearing (except when requested otherwise
362 	 * through the DRM_MODE_PAGE_FLIP_ASYNC flag). When an application
363 	 * requests a page flip the DRM core verifies that the new frame buffer
364 	 * is large enough to be scanned out by the CRTC in the currently
365 	 * configured mode and then calls this hook with a pointer to the new
366 	 * frame buffer.
367 	 *
368 	 * The driver must wait for any pending rendering to the new framebuffer
369 	 * to complete before executing the flip. It should also wait for any
370 	 * pending rendering from other drivers if the underlying buffer is a
371 	 * shared dma-buf.
372 	 *
373 	 * An application can request to be notified when the page flip has
374 	 * completed. The drm core will supply a &struct drm_event in the event
375 	 * parameter in this case. This can be handled by the
376 	 * drm_crtc_send_vblank_event() function, which the driver should call on
377 	 * the provided event upon completion of the flip. Note that if
378 	 * the driver supports vblank signalling and timestamping the vblank
379 	 * counters and timestamps must agree with the ones returned from page
380 	 * flip events. With the current vblank helper infrastructure this can
381 	 * be achieved by holding a vblank reference while the page flip is
382 	 * pending, acquired through drm_crtc_vblank_get() and released with
383 	 * drm_crtc_vblank_put(). Drivers are free to implement their own vblank
384 	 * counter and timestamp tracking though, e.g. if they have accurate
385 	 * timestamp registers in hardware.
386 	 *
387 	 * This callback is optional.
388 	 *
389 	 * NOTE:
390 	 *
391 	 * Very early versions of the KMS ABI mandated that the driver must
392 	 * block (but not reject) any rendering to the old framebuffer until the
393 	 * flip operation has completed and the old framebuffer is no longer
394 	 * visible. This requirement has been lifted, and userspace is instead
395 	 * expected to request delivery of an event and wait with recycling old
396 	 * buffers until such has been received.
397 	 *
398 	 * RETURNS:
399 	 *
400 	 * 0 on success or a negative error code on failure. Note that if a
401 	 * page flip operation is already pending the callback should return
402 	 * -EBUSY. Pageflips on a disabled CRTC (either by setting a NULL mode
403 	 * or just runtime disabled through DPMS respectively the new atomic
404 	 * "ACTIVE" state) should result in an -EINVAL error code. Note that
405 	 * drm_atomic_helper_page_flip() checks this already for atomic drivers.
406 	 */
407 	int (*page_flip)(struct drm_crtc *crtc,
408 			 struct drm_framebuffer *fb,
409 			 struct drm_pending_vblank_event *event,
410 			 uint32_t flags,
411 			 struct drm_modeset_acquire_ctx *ctx);
412 
413 	/**
414 	 * @page_flip_target:
415 	 *
416 	 * Same as @page_flip but with an additional parameter specifying the
417 	 * absolute target vertical blank period (as reported by
418 	 * drm_crtc_vblank_count()) when the flip should take effect.
419 	 *
420 	 * Note that the core code calls drm_crtc_vblank_get before this entry
421 	 * point, and will call drm_crtc_vblank_put if this entry point returns
422 	 * any non-0 error code. It's the driver's responsibility to call
423 	 * drm_crtc_vblank_put after this entry point returns 0, typically when
424 	 * the flip completes.
425 	 */
426 	int (*page_flip_target)(struct drm_crtc *crtc,
427 				struct drm_framebuffer *fb,
428 				struct drm_pending_vblank_event *event,
429 				uint32_t flags, uint32_t target,
430 				struct drm_modeset_acquire_ctx *ctx);
431 
432 	/**
433 	 * @set_property:
434 	 *
435 	 * This is the legacy entry point to update a property attached to the
436 	 * CRTC.
437 	 *
438 	 * Drivers implementing atomic modeset should use
439 	 * drm_atomic_helper_crtc_set_property() to implement this hook.
440 	 *
441 	 * This callback is optional if the driver does not support any legacy
442 	 * driver-private properties.
443 	 *
444 	 * RETURNS:
445 	 *
446 	 * 0 on success or a negative error code on failure.
447 	 */
448 	int (*set_property)(struct drm_crtc *crtc,
449 			    struct drm_property *property, uint64_t val);
450 
451 	/**
452 	 * @atomic_duplicate_state:
453 	 *
454 	 * Duplicate the current atomic state for this CRTC and return it.
455 	 * The core and helpers guarantee that any atomic state duplicated with
456 	 * this hook and still owned by the caller (i.e. not transferred to the
457 	 * driver by calling &drm_mode_config_funcs.atomic_commit) will be
458 	 * cleaned up by calling the @atomic_destroy_state hook in this
459 	 * structure.
460 	 *
461 	 * Atomic drivers which don't subclass &struct drm_crtc_state should use
462 	 * drm_atomic_helper_crtc_duplicate_state(). Drivers that subclass the
463 	 * state structure to extend it with driver-private state should use
464 	 * __drm_atomic_helper_crtc_duplicate_state() to make sure shared state is
465 	 * duplicated in a consistent fashion across drivers.
466 	 *
467 	 * It is an error to call this hook before &drm_crtc.state has been
468 	 * initialized correctly.
469 	 *
470 	 * NOTE:
471 	 *
472 	 * If the duplicate state references refcounted resources this hook must
473 	 * acquire a reference for each of them. The driver must release these
474 	 * references again in @atomic_destroy_state.
475 	 *
476 	 * RETURNS:
477 	 *
478 	 * Duplicated atomic state or NULL when the allocation failed.
479 	 */
480 	struct drm_crtc_state *(*atomic_duplicate_state)(struct drm_crtc *crtc);
481 
482 	/**
483 	 * @atomic_destroy_state:
484 	 *
485 	 * Destroy a state duplicated with @atomic_duplicate_state and release
486 	 * or unreference all resources it references
487 	 */
488 	void (*atomic_destroy_state)(struct drm_crtc *crtc,
489 				     struct drm_crtc_state *state);
490 
491 	/**
492 	 * @atomic_set_property:
493 	 *
494 	 * Decode a driver-private property value and store the decoded value
495 	 * into the passed-in state structure. Since the atomic core decodes all
496 	 * standardized properties (even for extensions beyond the core set of
497 	 * properties which might not be implemented by all drivers) this
498 	 * requires drivers to subclass the state structure.
499 	 *
500 	 * Such driver-private properties should really only be implemented for
501 	 * truly hardware/vendor specific state. Instead it is preferred to
502 	 * standardize atomic extension and decode the properties used to expose
503 	 * such an extension in the core.
504 	 *
505 	 * Do not call this function directly, use
506 	 * drm_atomic_crtc_set_property() instead.
507 	 *
508 	 * This callback is optional if the driver does not support any
509 	 * driver-private atomic properties.
510 	 *
511 	 * NOTE:
512 	 *
513 	 * This function is called in the state assembly phase of atomic
514 	 * modesets, which can be aborted for any reason (including on
515 	 * userspace's request to just check whether a configuration would be
516 	 * possible). Drivers MUST NOT touch any persistent state (hardware or
517 	 * software) or data structures except the passed in @state parameter.
518 	 *
519 	 * Also since userspace controls in which order properties are set this
520 	 * function must not do any input validation (since the state update is
521 	 * incomplete and hence likely inconsistent). Instead any such input
522 	 * validation must be done in the various atomic_check callbacks.
523 	 *
524 	 * RETURNS:
525 	 *
526 	 * 0 if the property has been found, -EINVAL if the property isn't
527 	 * implemented by the driver (which should never happen, the core only
528 	 * asks for properties attached to this CRTC). No other validation is
529 	 * allowed by the driver. The core already checks that the property
530 	 * value is within the range (integer, valid enum value, ...) the driver
531 	 * set when registering the property.
532 	 */
533 	int (*atomic_set_property)(struct drm_crtc *crtc,
534 				   struct drm_crtc_state *state,
535 				   struct drm_property *property,
536 				   uint64_t val);
537 	/**
538 	 * @atomic_get_property:
539 	 *
540 	 * Reads out the decoded driver-private property. This is used to
541 	 * implement the GETCRTC IOCTL.
542 	 *
543 	 * Do not call this function directly, use
544 	 * drm_atomic_crtc_get_property() instead.
545 	 *
546 	 * This callback is optional if the driver does not support any
547 	 * driver-private atomic properties.
548 	 *
549 	 * RETURNS:
550 	 *
551 	 * 0 on success, -EINVAL if the property isn't implemented by the
552 	 * driver (which should never happen, the core only asks for
553 	 * properties attached to this CRTC).
554 	 */
555 	int (*atomic_get_property)(struct drm_crtc *crtc,
556 				   const struct drm_crtc_state *state,
557 				   struct drm_property *property,
558 				   uint64_t *val);
559 
560 	/**
561 	 * @late_register:
562 	 *
563 	 * This optional hook can be used to register additional userspace
564 	 * interfaces attached to the crtc like debugfs interfaces.
565 	 * It is called late in the driver load sequence from drm_dev_register().
566 	 * Everything added from this callback should be unregistered in
567 	 * the early_unregister callback.
568 	 *
569 	 * Returns:
570 	 *
571 	 * 0 on success, or a negative error code on failure.
572 	 */
573 	int (*late_register)(struct drm_crtc *crtc);
574 
575 	/**
576 	 * @early_unregister:
577 	 *
578 	 * This optional hook should be used to unregister the additional
579 	 * userspace interfaces attached to the crtc from
580 	 * @late_register. It is called from drm_dev_unregister(),
581 	 * early in the driver unload sequence to disable userspace access
582 	 * before data structures are torndown.
583 	 */
584 	void (*early_unregister)(struct drm_crtc *crtc);
585 
586 	/**
587 	 * @set_crc_source:
588 	 *
589 	 * Changes the source of CRC checksums of frames at the request of
590 	 * userspace, typically for testing purposes. The sources available are
591 	 * specific of each driver and a %NULL value indicates that CRC
592 	 * generation is to be switched off.
593 	 *
594 	 * When CRC generation is enabled, the driver should call
595 	 * drm_crtc_add_crc_entry() at each frame, providing any information
596 	 * that characterizes the frame contents in the crcN arguments, as
597 	 * provided from the configured source. Drivers must accept an "auto"
598 	 * source name that will select a default source for this CRTC.
599 	 *
600 	 * Note that "auto" can depend upon the current modeset configuration,
601 	 * e.g. it could pick an encoder or output specific CRC sampling point.
602 	 *
603 	 * This callback is optional if the driver does not support any CRC
604 	 * generation functionality.
605 	 *
606 	 * RETURNS:
607 	 *
608 	 * 0 on success or a negative error code on failure.
609 	 */
610 	int (*set_crc_source)(struct drm_crtc *crtc, const char *source,
611 			      size_t *values_cnt);
612 
613 	/**
614 	 * @atomic_print_state:
615 	 *
616 	 * If driver subclasses &struct drm_crtc_state, it should implement
617 	 * this optional hook for printing additional driver specific state.
618 	 *
619 	 * Do not call this directly, use drm_atomic_crtc_print_state()
620 	 * instead.
621 	 */
622 	void (*atomic_print_state)(struct drm_printer *p,
623 				   const struct drm_crtc_state *state);
624 
625 	/**
626 	 * @get_vblank_counter:
627 	 *
628 	 * Driver callback for fetching a raw hardware vblank counter for the
629 	 * CRTC. It's meant to be used by new drivers as the replacement of
630 	 * &drm_driver.get_vblank_counter hook.
631 	 *
632 	 * This callback is optional. If a device doesn't have a hardware
633 	 * counter, the driver can simply leave the hook as NULL. The DRM core
634 	 * will account for missed vblank events while interrupts where disabled
635 	 * based on system timestamps.
636 	 *
637 	 * Wraparound handling and loss of events due to modesetting is dealt
638 	 * with in the DRM core code, as long as drivers call
639 	 * drm_crtc_vblank_off() and drm_crtc_vblank_on() when disabling or
640 	 * enabling a CRTC.
641 	 *
642 	 * Returns:
643 	 *
644 	 * Raw vblank counter value.
645 	 */
646 	u32 (*get_vblank_counter)(struct drm_crtc *crtc);
647 
648 	/**
649 	 * @enable_vblank:
650 	 *
651 	 * Enable vblank interrupts for the CRTC. It's meant to be used by
652 	 * new drivers as the replacement of &drm_driver.enable_vblank hook.
653 	 *
654 	 * Returns:
655 	 *
656 	 * Zero on success, appropriate errno if the vblank interrupt cannot
657 	 * be enabled.
658 	 */
659 	int (*enable_vblank)(struct drm_crtc *crtc);
660 
661 	/**
662 	 * @disable_vblank:
663 	 *
664 	 * Disable vblank interrupts for the CRTC. It's meant to be used by
665 	 * new drivers as the replacement of &drm_driver.disable_vblank hook.
666 	 */
667 	void (*disable_vblank)(struct drm_crtc *crtc);
668 };
669 
670 /**
671  * struct drm_crtc - central CRTC control structure
672  * @dev: parent DRM device
673  * @port: OF node used by drm_of_find_possible_crtcs()
674  * @head: list management
675  * @name: human readable name, can be overwritten by the driver
676  * @mutex: per-CRTC locking
677  * @base: base KMS object for ID tracking etc.
678  * @primary: primary plane for this CRTC
679  * @cursor: cursor plane for this CRTC
680  * @cursor_x: current x position of the cursor, used for universal cursor planes
681  * @cursor_y: current y position of the cursor, used for universal cursor planes
682  * @enabled: is this CRTC enabled?
683  * @mode: current mode timings
684  * @hwmode: mode timings as programmed to hw regs
685  * @x: x position on screen
686  * @y: y position on screen
687  * @funcs: CRTC control functions
688  * @gamma_size: size of gamma ramp
689  * @gamma_store: gamma ramp values
690  * @helper_private: mid-layer private data
691  * @properties: property tracking for this CRTC
692  *
693  * Each CRTC may have one or more connectors associated with it.  This structure
694  * allows the CRTC to be controlled.
695  */
696 struct drm_crtc {
697 	struct drm_device *dev;
698 	struct device_node *port;
699 	struct list_head head;
700 
701 	char *name;
702 
703 	/**
704 	 * @mutex:
705 	 *
706 	 * This provides a read lock for the overall CRTC state (mode, dpms
707 	 * state, ...) and a write lock for everything which can be update
708 	 * without a full modeset (fb, cursor data, CRTC properties ...). A full
709 	 * modeset also need to grab &drm_mode_config.connection_mutex.
710 	 *
711 	 * For atomic drivers specifically this protects @state.
712 	 */
713 	struct drm_modeset_lock mutex;
714 
715 	struct drm_mode_object base;
716 
717 	/* primary and cursor planes for CRTC */
718 	struct drm_plane *primary;
719 	struct drm_plane *cursor;
720 
721 	/**
722 	 * @index: Position inside the mode_config.list, can be used as an array
723 	 * index. It is invariant over the lifetime of the CRTC.
724 	 */
725 	unsigned index;
726 
727 	/* position of cursor plane on crtc */
728 	int cursor_x;
729 	int cursor_y;
730 
731 	bool enabled;
732 
733 	/* Requested mode from modesetting. */
734 	struct drm_display_mode mode;
735 
736 	/* Programmed mode in hw, after adjustments for encoders,
737 	 * crtc, panel scaling etc. Needed for timestamping etc.
738 	 */
739 	struct drm_display_mode hwmode;
740 
741 	int x, y;
742 	const struct drm_crtc_funcs *funcs;
743 
744 	/* Legacy FB CRTC gamma size for reporting to userspace */
745 	uint32_t gamma_size;
746 	uint16_t *gamma_store;
747 
748 	/* if you are using the helper */
749 	const struct drm_crtc_helper_funcs *helper_private;
750 
751 	struct drm_object_properties properties;
752 
753 	/**
754 	 * @state:
755 	 *
756 	 * Current atomic state for this CRTC.
757 	 *
758 	 * This is protected by @mutex. Note that nonblocking atomic commits
759 	 * access the current CRTC state without taking locks. Either by going
760 	 * through the &struct drm_atomic_state pointers, see
761 	 * for_each_crtc_in_state(), for_each_oldnew_crtc_in_state(),
762 	 * for_each_old_crtc_in_state() and for_each_new_crtc_in_state(). Or
763 	 * through careful ordering of atomic commit operations as implemented
764 	 * in the atomic helpers, see &struct drm_crtc_commit.
765 	 */
766 	struct drm_crtc_state *state;
767 
768 	/**
769 	 * @commit_list:
770 	 *
771 	 * List of &drm_crtc_commit structures tracking pending commits.
772 	 * Protected by @commit_lock. This list doesn't hold its own full
773 	 * reference, but burrows it from the ongoing commit. Commit entries
774 	 * must be removed from this list once the commit is fully completed,
775 	 * but before it's correspoding &drm_atomic_state gets destroyed.
776 	 */
777 	struct list_head commit_list;
778 
779 	/**
780 	 * @commit_lock:
781 	 *
782 	 * Spinlock to protect @commit_list.
783 	 */
784 	spinlock_t commit_lock;
785 
786 #ifdef CONFIG_DEBUG_FS
787 	/**
788 	 * @debugfs_entry:
789 	 *
790 	 * Debugfs directory for this CRTC.
791 	 */
792 	struct dentry *debugfs_entry;
793 #endif
794 
795 	/**
796 	 * @crc:
797 	 *
798 	 * Configuration settings of CRC capture.
799 	 */
800 	struct drm_crtc_crc crc;
801 
802 	/**
803 	 * @fence_context:
804 	 *
805 	 * timeline context used for fence operations.
806 	 */
807 	unsigned int fence_context;
808 
809 	/**
810 	 * @fence_lock:
811 	 *
812 	 * spinlock to protect the fences in the fence_context.
813 	 */
814 
815 	spinlock_t fence_lock;
816 	/**
817 	 * @fence_seqno:
818 	 *
819 	 * Seqno variable used as monotonic counter for the fences
820 	 * created on the CRTC's timeline.
821 	 */
822 	unsigned long fence_seqno;
823 
824 	/**
825 	 * @timeline_name:
826 	 *
827 	 * The name of the CRTC's fence timeline.
828 	 */
829 	char timeline_name[32];
830 };
831 
832 /**
833  * struct drm_mode_set - new values for a CRTC config change
834  * @fb: framebuffer to use for new config
835  * @crtc: CRTC whose configuration we're about to change
836  * @mode: mode timings to use
837  * @x: position of this CRTC relative to @fb
838  * @y: position of this CRTC relative to @fb
839  * @connectors: array of connectors to drive with this CRTC if possible
840  * @num_connectors: size of @connectors array
841  *
842  * This represents a modeset configuration for the legacy SETCRTC ioctl and is
843  * also used internally. Atomic drivers instead use &drm_atomic_state.
844  */
845 struct drm_mode_set {
846 	struct drm_framebuffer *fb;
847 	struct drm_crtc *crtc;
848 	struct drm_display_mode *mode;
849 
850 	uint32_t x;
851 	uint32_t y;
852 
853 	struct drm_connector **connectors;
854 	size_t num_connectors;
855 };
856 
857 #define obj_to_crtc(x) container_of(x, struct drm_crtc, base)
858 
859 __printf(6, 7)
860 int drm_crtc_init_with_planes(struct drm_device *dev,
861 			      struct drm_crtc *crtc,
862 			      struct drm_plane *primary,
863 			      struct drm_plane *cursor,
864 			      const struct drm_crtc_funcs *funcs,
865 			      const char *name, ...);
866 void drm_crtc_cleanup(struct drm_crtc *crtc);
867 
868 /**
869  * drm_crtc_index - find the index of a registered CRTC
870  * @crtc: CRTC to find index for
871  *
872  * Given a registered CRTC, return the index of that CRTC within a DRM
873  * device's list of CRTCs.
874  */
875 static inline unsigned int drm_crtc_index(const struct drm_crtc *crtc)
876 {
877 	return crtc->index;
878 }
879 
880 /**
881  * drm_crtc_mask - find the mask of a registered CRTC
882  * @crtc: CRTC to find mask for
883  *
884  * Given a registered CRTC, return the mask bit of that CRTC for an
885  * encoder's possible_crtcs field.
886  */
887 static inline uint32_t drm_crtc_mask(const struct drm_crtc *crtc)
888 {
889 	return 1 << drm_crtc_index(crtc);
890 }
891 
892 int drm_crtc_force_disable(struct drm_crtc *crtc);
893 int drm_crtc_force_disable_all(struct drm_device *dev);
894 
895 int drm_mode_set_config_internal(struct drm_mode_set *set);
896 struct drm_crtc *drm_crtc_from_index(struct drm_device *dev, int idx);
897 
898 /**
899  * drm_crtc_find - look up a CRTC object from its ID
900  * @dev: DRM device
901  * @id: &drm_mode_object ID
902  *
903  * This can be used to look up a CRTC from its userspace ID. Only used by
904  * drivers for legacy IOCTLs and interface, nowadays extensions to the KMS
905  * userspace interface should be done using &drm_property.
906  */
907 static inline struct drm_crtc *drm_crtc_find(struct drm_device *dev,
908 	uint32_t id)
909 {
910 	struct drm_mode_object *mo;
911 	mo = drm_mode_object_find(dev, id, DRM_MODE_OBJECT_CRTC);
912 	return mo ? obj_to_crtc(mo) : NULL;
913 }
914 
915 /**
916  * drm_for_each_crtc - iterate over all CRTCs
917  * @crtc: a &struct drm_crtc as the loop cursor
918  * @dev: the &struct drm_device
919  *
920  * Iterate over all CRTCs of @dev.
921  */
922 #define drm_for_each_crtc(crtc, dev) \
923 	list_for_each_entry(crtc, &(dev)->mode_config.crtc_list, head)
924 
925 #endif /* __DRM_CRTC_H__ */
926