1 /*        $NetBSD: drm_crtc.h,v 1.9 2021/12/18 23:45:45 riastradh Exp $         */
2 
3 /*
4  * Copyright © 2006 Keith Packard
5  * Copyright © 2007-2008 Dave Airlie
6  * Copyright © 2007-2008 Intel Corporation
7  *   Jesse Barnes <jesse.barnes@intel.com>
8  *
9  * Permission is hereby granted, free of charge, to any person obtaining a
10  * copy of this software and associated documentation files (the "Software"),
11  * to deal in the Software without restriction, including without limitation
12  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
13  * and/or sell copies of the Software, and to permit persons to whom the
14  * Software is furnished to do so, subject to the following conditions:
15  *
16  * The above copyright notice and this permission notice shall be included in
17  * all copies or substantial portions of the Software.
18  *
19  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
20  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
21  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
22  * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
23  * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
24  * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
25  * OTHER DEALINGS IN THE SOFTWARE.
26  */
27 #ifndef __DRM_CRTC_H__
28 #define __DRM_CRTC_H__
29 
30 #include <linux/i2c.h>
31 #include <linux/spinlock.h>
32 #include <linux/types.h>
33 #include <linux/fb.h>
34 #include <linux/hdmi.h>
35 #include <linux/media-bus-format.h>
36 #include <linux/kref.h>
37 #include <linux/mutex.h>
38 #include <linux/workqueue.h>
39 #include <uapi/drm/drm_mode.h>
40 #include <uapi/drm/drm_fourcc.h>
41 #include <drm/drm_modeset_lock.h>
42 #include <drm/drm_rect.h>
43 #include <drm/drm_mode_object.h>
44 #include <drm/drm_framebuffer.h>
45 #include <drm/drm_modes.h>
46 #include <drm/drm_connector.h>
47 #include <drm/drm_device.h>
48 #include <drm/drm_property.h>
49 #include <drm/drm_edid.h>
50 #include <drm/drm_plane.h>
51 #include <drm/drm_blend.h>
52 #include <drm/drm_color_mgmt.h>
53 #include <drm/drm_debugfs_crc.h>
54 #include <drm/drm_mode_config.h>
55 
56 struct drm_device;
57 struct drm_mode_set;
58 struct drm_file;
59 struct drm_clip_rect;
60 struct drm_printer;
61 struct drm_self_refresh_data;
62 struct device_node;
63 struct dma_fence;
64 struct edid;
65 
U642I64(uint64_t val)66 static inline int64_t U642I64(uint64_t val)
67 {
68           return (int64_t)*((int64_t *)&val);
69 }
I642U64(int64_t val)70 static inline uint64_t I642U64(int64_t val)
71 {
72           return (uint64_t)*((uint64_t *)&val);
73 }
74 
75 struct drm_crtc;
76 struct drm_pending_vblank_event;
77 struct drm_plane;
78 struct drm_bridge;
79 struct drm_atomic_state;
80 
81 struct drm_crtc_helper_funcs;
82 struct drm_plane_helper_funcs;
83 
84 /**
85  * struct drm_crtc_state - mutable CRTC state
86  *
87  * Note that the distinction between @enable and @active is rather subtle:
88  * Flipping @active while @enable is set without changing anything else may
89  * never return in a failure from the &drm_mode_config_funcs.atomic_check
90  * callback. Userspace assumes that a DPMS On will always succeed. In other
91  * words: @enable controls resource assignment, @active controls the actual
92  * hardware state.
93  *
94  * The three booleans active_changed, connectors_changed and mode_changed are
95  * intended to indicate whether a full modeset is needed, rather than strictly
96  * describing what has changed in a commit. See also:
97  * drm_atomic_crtc_needs_modeset()
98  *
99  * WARNING: Transitional helpers (like drm_helper_crtc_mode_set() or
100  * drm_helper_crtc_mode_set_base()) do not maintain many of the derived control
101  * state like @plane_mask so drivers not converted over to atomic helpers should
102  * not rely on these being accurate!
103  */
104 struct drm_crtc_state {
105           /** @crtc: backpointer to the CRTC */
106           struct drm_crtc *crtc;
107 
108           /**
109            * @enable: Whether the CRTC should be enabled, gates all other state.
110            * This controls reservations of shared resources. Actual hardware state
111            * is controlled by @active.
112            */
113           bool enable;
114 
115           /**
116            * @active: Whether the CRTC is actively displaying (used for DPMS).
117            * Implies that @enable is set. The driver must not release any shared
118            * resources if @active is set to false but @enable still true, because
119            * userspace expects that a DPMS ON always succeeds.
120            *
121            * Hence drivers must not consult @active in their various
122            * &drm_mode_config_funcs.atomic_check callback to reject an atomic
123            * commit. They can consult it to aid in the computation of derived
124            * hardware state, since even in the DPMS OFF state the display hardware
125            * should be as much powered down as when the CRTC is completely
126            * disabled through setting @enable to false.
127            */
128           bool active;
129 
130           /**
131            * @planes_changed: Planes on this crtc are updated. Used by the atomic
132            * helpers and drivers to steer the atomic commit control flow.
133            */
134           bool planes_changed : 1;
135 
136           /**
137            * @mode_changed: @mode or @enable has been changed. Used by the atomic
138            * helpers and drivers to steer the atomic commit control flow. See also
139            * drm_atomic_crtc_needs_modeset().
140            *
141            * Drivers are supposed to set this for any CRTC state changes that
142            * require a full modeset. They can also reset it to false if e.g. a
143            * @mode change can be done without a full modeset by only changing
144            * scaler settings.
145            */
146           bool mode_changed : 1;
147 
148           /**
149            * @active_changed: @active has been toggled. Used by the atomic
150            * helpers and drivers to steer the atomic commit control flow. See also
151            * drm_atomic_crtc_needs_modeset().
152            */
153           bool active_changed : 1;
154 
155           /**
156            * @connectors_changed: Connectors to this crtc have been updated,
157            * either in their state or routing. Used by the atomic
158            * helpers and drivers to steer the atomic commit control flow. See also
159            * drm_atomic_crtc_needs_modeset().
160            *
161            * Drivers are supposed to set this as-needed from their own atomic
162            * check code, e.g. from &drm_encoder_helper_funcs.atomic_check
163            */
164           bool connectors_changed : 1;
165           /**
166            * @zpos_changed: zpos values of planes on this crtc have been updated.
167            * Used by the atomic helpers and drivers to steer the atomic commit
168            * control flow.
169            */
170           bool zpos_changed : 1;
171           /**
172            * @color_mgmt_changed: Color management properties have changed
173            * (@gamma_lut, @degamma_lut or @ctm). Used by the atomic helpers and
174            * drivers to steer the atomic commit control flow.
175            */
176           bool color_mgmt_changed : 1;
177 
178           /**
179            * @no_vblank:
180            *
181            * Reflects the ability of a CRTC to send VBLANK events. This state
182            * usually depends on the pipeline configuration, and the main usuage
183            * is CRTCs feeding a writeback connector operating in oneshot mode.
184            * In this case the VBLANK event is only generated when a job is queued
185            * to the writeback connector, and we want the core to fake VBLANK
186            * events when this part of the pipeline hasn't changed but others had
187            * or when the CRTC and connectors are being disabled.
188            *
189            * __drm_atomic_helper_crtc_duplicate_state() will not reset the value
190            * from the current state, the CRTC driver is then responsible for
191            * updating this field when needed.
192            *
193            * Note that the combination of &drm_crtc_state.event == NULL and
194            * &drm_crtc_state.no_blank == true is valid and usually used when the
195            * writeback connector attached to the CRTC has a new job queued. In
196            * this case the driver will send the VBLANK event on its own when the
197            * writeback job is complete.
198            */
199           bool no_vblank : 1;
200 
201           /**
202            * @plane_mask: Bitmask of drm_plane_mask(plane) of planes attached to
203            * this CRTC.
204            */
205           u32 plane_mask;
206 
207           /**
208            * @connector_mask: Bitmask of drm_connector_mask(connector) of
209            * connectors attached to this CRTC.
210            */
211           u32 connector_mask;
212 
213           /**
214            * @encoder_mask: Bitmask of drm_encoder_mask(encoder) of encoders
215            * attached to this CRTC.
216            */
217           u32 encoder_mask;
218 
219           /**
220            * @adjusted_mode:
221            *
222            * Internal display timings which can be used by the driver to handle
223            * differences between the mode requested by userspace in @mode and what
224            * is actually programmed into the hardware.
225            *
226            * For drivers using &drm_bridge, this stores hardware display timings
227            * used between the CRTC and the first bridge. For other drivers, the
228            * meaning of the adjusted_mode field is purely driver implementation
229            * defined information, and will usually be used to store the hardware
230            * display timings used between the CRTC and encoder blocks.
231            */
232           struct drm_display_mode adjusted_mode;
233 
234           /**
235            * @mode:
236            *
237            * Display timings requested by userspace. The driver should try to
238            * match the refresh rate as close as possible (but note that it's
239            * undefined what exactly is close enough, e.g. some of the HDMI modes
240            * only differ in less than 1% of the refresh rate). The active width
241            * and height as observed by userspace for positioning planes must match
242            * exactly.
243            *
244            * For external connectors where the sink isn't fixed (like with a
245            * built-in panel), this mode here should match the physical mode on the
246            * wire to the last details (i.e. including sync polarities and
247            * everything).
248            */
249           struct drm_display_mode mode;
250 
251           /**
252            * @mode_blob: &drm_property_blob for @mode, for exposing the mode to
253            * atomic userspace.
254            */
255           struct drm_property_blob *mode_blob;
256 
257           /**
258            * @degamma_lut:
259            *
260            * Lookup table for converting framebuffer pixel data before apply the
261            * color conversion matrix @ctm. See drm_crtc_enable_color_mgmt(). The
262            * blob (if not NULL) is an array of &struct drm_color_lut.
263            */
264           struct drm_property_blob *degamma_lut;
265 
266           /**
267            * @ctm:
268            *
269            * Color transformation matrix. See drm_crtc_enable_color_mgmt(). The
270            * blob (if not NULL) is a &struct drm_color_ctm.
271            */
272           struct drm_property_blob *ctm;
273 
274           /**
275            * @gamma_lut:
276            *
277            * Lookup table for converting pixel data after the color conversion
278            * matrix @ctm.  See drm_crtc_enable_color_mgmt(). The blob (if not
279            * NULL) is an array of &struct drm_color_lut.
280            */
281           struct drm_property_blob *gamma_lut;
282 
283           /**
284            * @target_vblank:
285            *
286            * Target vertical blank period when a page flip
287            * should take effect.
288            */
289           u32 target_vblank;
290 
291           /**
292            * @async_flip:
293            *
294            * This is set when DRM_MODE_PAGE_FLIP_ASYNC is set in the legacy
295            * PAGE_FLIP IOCTL. It's not wired up for the atomic IOCTL itself yet.
296            */
297           bool async_flip;
298 
299           /**
300            * @vrr_enabled:
301            *
302            * Indicates if variable refresh rate should be enabled for the CRTC.
303            * Support for the requested vrr state will depend on driver and
304            * hardware capabiltiy - lacking support is not treated as failure.
305            */
306           bool vrr_enabled;
307 
308           /**
309            * @self_refresh_active:
310            *
311            * Used by the self refresh helpers to denote when a self refresh
312            * transition is occurring. This will be set on enable/disable callbacks
313            * when self refresh is being enabled or disabled. In some cases, it may
314            * not be desirable to fully shut off the crtc during self refresh.
315            * CRTC's can inspect this flag and determine the best course of action.
316            */
317           bool self_refresh_active;
318 
319           /**
320            * @event:
321            *
322            * Optional pointer to a DRM event to signal upon completion of the
323            * state update. The driver must send out the event when the atomic
324            * commit operation completes. There are two cases:
325            *
326            *  - The event is for a CRTC which is being disabled through this
327            *    atomic commit. In that case the event can be send out any time
328            *    after the hardware has stopped scanning out the current
329            *    framebuffers. It should contain the timestamp and counter for the
330            *    last vblank before the display pipeline was shut off. The simplest
331            *    way to achieve that is calling drm_crtc_send_vblank_event()
332            *    somewhen after drm_crtc_vblank_off() has been called.
333            *
334            *  - For a CRTC which is enabled at the end of the commit (even when it
335            *    undergoes an full modeset) the vblank timestamp and counter must
336            *    be for the vblank right before the first frame that scans out the
337            *    new set of buffers. Again the event can only be sent out after the
338            *    hardware has stopped scanning out the old buffers.
339            *
340            *  - Events for disabled CRTCs are not allowed, and drivers can ignore
341            *    that case.
342            *
343            * This can be handled by the drm_crtc_send_vblank_event() function,
344            * which the driver should call on the provided event upon completion of
345            * the atomic commit. Note that if the driver supports vblank signalling
346            * and timestamping the vblank counters and timestamps must agree with
347            * the ones returned from page flip events. With the current vblank
348            * helper infrastructure this can be achieved by holding a vblank
349            * reference while the page flip is pending, acquired through
350            * drm_crtc_vblank_get() and released with drm_crtc_vblank_put().
351            * Drivers are free to implement their own vblank counter and timestamp
352            * tracking though, e.g. if they have accurate timestamp registers in
353            * hardware.
354            *
355            * For hardware which supports some means to synchronize vblank
356            * interrupt delivery with committing display state there's also
357            * drm_crtc_arm_vblank_event(). See the documentation of that function
358            * for a detailed discussion of the constraints it needs to be used
359            * safely.
360            *
361            * If the device can't notify of flip completion in a race-free way
362            * at all, then the event should be armed just after the page flip is
363            * committed. In the worst case the driver will send the event to
364            * userspace one frame too late. This doesn't allow for a real atomic
365            * update, but it should avoid tearing.
366            */
367           struct drm_pending_vblank_event *event;
368 
369           /**
370            * @commit:
371            *
372            * This tracks how the commit for this update proceeds through the
373            * various phases. This is never cleared, except when we destroy the
374            * state, so that subsequent commits can synchronize with previous ones.
375            */
376           struct drm_crtc_commit *commit;
377 
378           /** @state: backpointer to global drm_atomic_state */
379           struct drm_atomic_state *state;
380 };
381 
382 /**
383  * struct drm_crtc_funcs - control CRTCs for a given device
384  *
385  * The drm_crtc_funcs structure is the central CRTC management structure
386  * in the DRM.  Each CRTC controls one or more connectors (note that the name
387  * CRTC is simply historical, a CRTC may control LVDS, VGA, DVI, TV out, etc.
388  * connectors, not just CRTs).
389  *
390  * Each driver is responsible for filling out this structure at startup time,
391  * in addition to providing other modesetting features, like i2c and DDC
392  * bus accessors.
393  */
394 struct drm_crtc_funcs {
395           /**
396            * @reset:
397            *
398            * Reset CRTC hardware and software state to off. This function isn't
399            * called by the core directly, only through drm_mode_config_reset().
400            * It's not a helper hook only for historical reasons.
401            *
402            * Atomic drivers can use drm_atomic_helper_crtc_reset() to reset
403            * atomic state using this hook.
404            */
405           void (*reset)(struct drm_crtc *crtc);
406 
407           /**
408            * @cursor_set:
409            *
410            * Update the cursor image. The cursor position is relative to the CRTC
411            * and can be partially or fully outside of the visible area.
412            *
413            * Note that contrary to all other KMS functions the legacy cursor entry
414            * points don't take a framebuffer object, but instead take directly a
415            * raw buffer object id from the driver's buffer manager (which is
416            * either GEM or TTM for current drivers).
417            *
418            * This entry point is deprecated, drivers should instead implement
419            * universal plane support and register a proper cursor plane using
420            * drm_crtc_init_with_planes().
421            *
422            * This callback is optional
423            *
424            * RETURNS:
425            *
426            * 0 on success or a negative error code on failure.
427            */
428           int (*cursor_set)(struct drm_crtc *crtc, struct drm_file *file_priv,
429                                 uint32_t handle, uint32_t width, uint32_t height);
430 
431           /**
432            * @cursor_set2:
433            *
434            * Update the cursor image, including hotspot information. The hotspot
435            * must not affect the cursor position in CRTC coordinates, but is only
436            * meant as a hint for virtualized display hardware to coordinate the
437            * guests and hosts cursor position. The cursor hotspot is relative to
438            * the cursor image. Otherwise this works exactly like @cursor_set.
439            *
440            * This entry point is deprecated, drivers should instead implement
441            * universal plane support and register a proper cursor plane using
442            * drm_crtc_init_with_planes().
443            *
444            * This callback is optional.
445            *
446            * RETURNS:
447            *
448            * 0 on success or a negative error code on failure.
449            */
450           int (*cursor_set2)(struct drm_crtc *crtc, struct drm_file *file_priv,
451                                  uint32_t handle, uint32_t width, uint32_t height,
452                                  int32_t hot_x, int32_t hot_y);
453 
454           /**
455            * @cursor_move:
456            *
457            * Update the cursor position. The cursor does not need to be visible
458            * when this hook is called.
459            *
460            * This entry point is deprecated, drivers should instead implement
461            * universal plane support and register a proper cursor plane using
462            * drm_crtc_init_with_planes().
463            *
464            * This callback is optional.
465            *
466            * RETURNS:
467            *
468            * 0 on success or a negative error code on failure.
469            */
470           int (*cursor_move)(struct drm_crtc *crtc, int x, int y);
471 
472           /**
473            * @gamma_set:
474            *
475            * Set gamma on the CRTC.
476            *
477            * This callback is optional.
478            *
479            * Atomic drivers who want to support gamma tables should implement the
480            * atomic color management support, enabled by calling
481            * drm_crtc_enable_color_mgmt(), which then supports the legacy gamma
482            * interface through the drm_atomic_helper_legacy_gamma_set()
483            * compatibility implementation.
484            */
485           int (*gamma_set)(struct drm_crtc *crtc, u16 *r, u16 *g, u16 *b,
486                                uint32_t size,
487                                struct drm_modeset_acquire_ctx *ctx);
488 
489           /**
490            * @destroy:
491            *
492            * Clean up CRTC resources. This is only called at driver unload time
493            * through drm_mode_config_cleanup() since a CRTC cannot be hotplugged
494            * in DRM.
495            */
496           void (*destroy)(struct drm_crtc *crtc);
497 
498           /**
499            * @set_config:
500            *
501            * This is the main legacy entry point to change the modeset state on a
502            * CRTC. All the details of the desired configuration are passed in a
503            * &struct drm_mode_set - see there for details.
504            *
505            * Drivers implementing atomic modeset should use
506            * drm_atomic_helper_set_config() to implement this hook.
507            *
508            * RETURNS:
509            *
510            * 0 on success or a negative error code on failure.
511            */
512           int (*set_config)(struct drm_mode_set *set,
513                                 struct drm_modeset_acquire_ctx *ctx);
514 
515           /**
516            * @page_flip:
517            *
518            * Legacy entry point to schedule a flip to the given framebuffer.
519            *
520            * Page flipping is a synchronization mechanism that replaces the frame
521            * buffer being scanned out by the CRTC with a new frame buffer during
522            * vertical blanking, avoiding tearing (except when requested otherwise
523            * through the DRM_MODE_PAGE_FLIP_ASYNC flag). When an application
524            * requests a page flip the DRM core verifies that the new frame buffer
525            * is large enough to be scanned out by the CRTC in the currently
526            * configured mode and then calls this hook with a pointer to the new
527            * frame buffer.
528            *
529            * The driver must wait for any pending rendering to the new framebuffer
530            * to complete before executing the flip. It should also wait for any
531            * pending rendering from other drivers if the underlying buffer is a
532            * shared dma-buf.
533            *
534            * An application can request to be notified when the page flip has
535            * completed. The drm core will supply a &struct drm_event in the event
536            * parameter in this case. This can be handled by the
537            * drm_crtc_send_vblank_event() function, which the driver should call on
538            * the provided event upon completion of the flip. Note that if
539            * the driver supports vblank signalling and timestamping the vblank
540            * counters and timestamps must agree with the ones returned from page
541            * flip events. With the current vblank helper infrastructure this can
542            * be achieved by holding a vblank reference while the page flip is
543            * pending, acquired through drm_crtc_vblank_get() and released with
544            * drm_crtc_vblank_put(). Drivers are free to implement their own vblank
545            * counter and timestamp tracking though, e.g. if they have accurate
546            * timestamp registers in hardware.
547            *
548            * This callback is optional.
549            *
550            * NOTE:
551            *
552            * Very early versions of the KMS ABI mandated that the driver must
553            * block (but not reject) any rendering to the old framebuffer until the
554            * flip operation has completed and the old framebuffer is no longer
555            * visible. This requirement has been lifted, and userspace is instead
556            * expected to request delivery of an event and wait with recycling old
557            * buffers until such has been received.
558            *
559            * RETURNS:
560            *
561            * 0 on success or a negative error code on failure. Note that if a
562            * page flip operation is already pending the callback should return
563            * -EBUSY. Pageflips on a disabled CRTC (either by setting a NULL mode
564            * or just runtime disabled through DPMS respectively the new atomic
565            * "ACTIVE" state) should result in an -EINVAL error code. Note that
566            * drm_atomic_helper_page_flip() checks this already for atomic drivers.
567            */
568           int (*page_flip)(struct drm_crtc *crtc,
569                                struct drm_framebuffer *fb,
570                                struct drm_pending_vblank_event *event,
571                                uint32_t flags,
572                                struct drm_modeset_acquire_ctx *ctx);
573 
574           /**
575            * @page_flip_target:
576            *
577            * Same as @page_flip but with an additional parameter specifying the
578            * absolute target vertical blank period (as reported by
579            * drm_crtc_vblank_count()) when the flip should take effect.
580            *
581            * Note that the core code calls drm_crtc_vblank_get before this entry
582            * point, and will call drm_crtc_vblank_put if this entry point returns
583            * any non-0 error code. It's the driver's responsibility to call
584            * drm_crtc_vblank_put after this entry point returns 0, typically when
585            * the flip completes.
586            */
587           int (*page_flip_target)(struct drm_crtc *crtc,
588                                         struct drm_framebuffer *fb,
589                                         struct drm_pending_vblank_event *event,
590                                         uint32_t flags, uint32_t target,
591                                         struct drm_modeset_acquire_ctx *ctx);
592 
593           /**
594            * @set_property:
595            *
596            * This is the legacy entry point to update a property attached to the
597            * CRTC.
598            *
599            * This callback is optional if the driver does not support any legacy
600            * driver-private properties. For atomic drivers it is not used because
601            * property handling is done entirely in the DRM core.
602            *
603            * RETURNS:
604            *
605            * 0 on success or a negative error code on failure.
606            */
607           int (*set_property)(struct drm_crtc *crtc,
608                                   struct drm_property *property, uint64_t val);
609 
610           /**
611            * @atomic_duplicate_state:
612            *
613            * Duplicate the current atomic state for this CRTC and return it.
614            * The core and helpers guarantee that any atomic state duplicated with
615            * this hook and still owned by the caller (i.e. not transferred to the
616            * driver by calling &drm_mode_config_funcs.atomic_commit) will be
617            * cleaned up by calling the @atomic_destroy_state hook in this
618            * structure.
619            *
620            * This callback is mandatory for atomic drivers.
621            *
622            * Atomic drivers which don't subclass &struct drm_crtc_state should use
623            * drm_atomic_helper_crtc_duplicate_state(). Drivers that subclass the
624            * state structure to extend it with driver-private state should use
625            * __drm_atomic_helper_crtc_duplicate_state() to make sure shared state is
626            * duplicated in a consistent fashion across drivers.
627            *
628            * It is an error to call this hook before &drm_crtc.state has been
629            * initialized correctly.
630            *
631            * NOTE:
632            *
633            * If the duplicate state references refcounted resources this hook must
634            * acquire a reference for each of them. The driver must release these
635            * references again in @atomic_destroy_state.
636            *
637            * RETURNS:
638            *
639            * Duplicated atomic state or NULL when the allocation failed.
640            */
641           struct drm_crtc_state *(*atomic_duplicate_state)(struct drm_crtc *crtc);
642 
643           /**
644            * @atomic_destroy_state:
645            *
646            * Destroy a state duplicated with @atomic_duplicate_state and release
647            * or unreference all resources it references
648            *
649            * This callback is mandatory for atomic drivers.
650            */
651           void (*atomic_destroy_state)(struct drm_crtc *crtc,
652                                              struct drm_crtc_state *state);
653 
654           /**
655            * @atomic_set_property:
656            *
657            * Decode a driver-private property value and store the decoded value
658            * into the passed-in state structure. Since the atomic core decodes all
659            * standardized properties (even for extensions beyond the core set of
660            * properties which might not be implemented by all drivers) this
661            * requires drivers to subclass the state structure.
662            *
663            * Such driver-private properties should really only be implemented for
664            * truly hardware/vendor specific state. Instead it is preferred to
665            * standardize atomic extension and decode the properties used to expose
666            * such an extension in the core.
667            *
668            * Do not call this function directly, use
669            * drm_atomic_crtc_set_property() instead.
670            *
671            * This callback is optional if the driver does not support any
672            * driver-private atomic properties.
673            *
674            * NOTE:
675            *
676            * This function is called in the state assembly phase of atomic
677            * modesets, which can be aborted for any reason (including on
678            * userspace's request to just check whether a configuration would be
679            * possible). Drivers MUST NOT touch any persistent state (hardware or
680            * software) or data structures except the passed in @state parameter.
681            *
682            * Also since userspace controls in which order properties are set this
683            * function must not do any input validation (since the state update is
684            * incomplete and hence likely inconsistent). Instead any such input
685            * validation must be done in the various atomic_check callbacks.
686            *
687            * RETURNS:
688            *
689            * 0 if the property has been found, -EINVAL if the property isn't
690            * implemented by the driver (which should never happen, the core only
691            * asks for properties attached to this CRTC). No other validation is
692            * allowed by the driver. The core already checks that the property
693            * value is within the range (integer, valid enum value, ...) the driver
694            * set when registering the property.
695            */
696           int (*atomic_set_property)(struct drm_crtc *crtc,
697                                            struct drm_crtc_state *state,
698                                            struct drm_property *property,
699                                            uint64_t val);
700           /**
701            * @atomic_get_property:
702            *
703            * Reads out the decoded driver-private property. This is used to
704            * implement the GETCRTC IOCTL.
705            *
706            * Do not call this function directly, use
707            * drm_atomic_crtc_get_property() instead.
708            *
709            * This callback is optional if the driver does not support any
710            * driver-private atomic properties.
711            *
712            * RETURNS:
713            *
714            * 0 on success, -EINVAL if the property isn't implemented by the
715            * driver (which should never happen, the core only asks for
716            * properties attached to this CRTC).
717            */
718           int (*atomic_get_property)(struct drm_crtc *crtc,
719                                            const struct drm_crtc_state *state,
720                                            struct drm_property *property,
721                                            uint64_t *val);
722 
723           /**
724            * @late_register:
725            *
726            * This optional hook can be used to register additional userspace
727            * interfaces attached to the crtc like debugfs interfaces.
728            * It is called late in the driver load sequence from drm_dev_register().
729            * Everything added from this callback should be unregistered in
730            * the early_unregister callback.
731            *
732            * Returns:
733            *
734            * 0 on success, or a negative error code on failure.
735            */
736           int (*late_register)(struct drm_crtc *crtc);
737 
738           /**
739            * @early_unregister:
740            *
741            * This optional hook should be used to unregister the additional
742            * userspace interfaces attached to the crtc from
743            * @late_register. It is called from drm_dev_unregister(),
744            * early in the driver unload sequence to disable userspace access
745            * before data structures are torndown.
746            */
747           void (*early_unregister)(struct drm_crtc *crtc);
748 
749           /**
750            * @set_crc_source:
751            *
752            * Changes the source of CRC checksums of frames at the request of
753            * userspace, typically for testing purposes. The sources available are
754            * specific of each driver and a %NULL value indicates that CRC
755            * generation is to be switched off.
756            *
757            * When CRC generation is enabled, the driver should call
758            * drm_crtc_add_crc_entry() at each frame, providing any information
759            * that characterizes the frame contents in the crcN arguments, as
760            * provided from the configured source. Drivers must accept an "auto"
761            * source name that will select a default source for this CRTC.
762            *
763            * This may trigger an atomic modeset commit if necessary, to enable CRC
764            * generation.
765            *
766            * Note that "auto" can depend upon the current modeset configuration,
767            * e.g. it could pick an encoder or output specific CRC sampling point.
768            *
769            * This callback is optional if the driver does not support any CRC
770            * generation functionality.
771            *
772            * RETURNS:
773            *
774            * 0 on success or a negative error code on failure.
775            */
776           int (*set_crc_source)(struct drm_crtc *crtc, const char *source);
777 
778           /**
779            * @verify_crc_source:
780            *
781            * verifies the source of CRC checksums of frames before setting the
782            * source for CRC and during crc open. Source parameter can be NULL
783            * while disabling crc source.
784            *
785            * This callback is optional if the driver does not support any CRC
786            * generation functionality.
787            *
788            * RETURNS:
789            *
790            * 0 on success or a negative error code on failure.
791            */
792           int (*verify_crc_source)(struct drm_crtc *crtc, const char *source,
793                                          size_t *values_cnt);
794           /**
795            * @get_crc_sources:
796            *
797            * Driver callback for getting a list of all the available sources for
798            * CRC generation. This callback depends upon verify_crc_source, So
799            * verify_crc_source callback should be implemented before implementing
800            * this. Driver can pass full list of available crc sources, this
801            * callback does the verification on each crc-source before passing it
802            * to userspace.
803            *
804            * This callback is optional if the driver does not support exporting of
805            * possible CRC sources list.
806            *
807            * RETURNS:
808            *
809            * a constant character pointer to the list of all the available CRC
810            * sources. On failure driver should return NULL. count should be
811            * updated with number of sources in list. if zero we don't process any
812            * source from the list.
813            */
814           const char *const *(*get_crc_sources)(struct drm_crtc *crtc,
815                                                         size_t *count);
816 
817           /**
818            * @atomic_print_state:
819            *
820            * If driver subclasses &struct drm_crtc_state, it should implement
821            * this optional hook for printing additional driver specific state.
822            *
823            * Do not call this directly, use drm_atomic_crtc_print_state()
824            * instead.
825            */
826           void (*atomic_print_state)(struct drm_printer *p,
827                                            const struct drm_crtc_state *state);
828 
829           /**
830            * @get_vblank_counter:
831            *
832            * Driver callback for fetching a raw hardware vblank counter for the
833            * CRTC. It's meant to be used by new drivers as the replacement of
834            * &drm_driver.get_vblank_counter hook.
835            *
836            * This callback is optional. If a device doesn't have a hardware
837            * counter, the driver can simply leave the hook as NULL. The DRM core
838            * will account for missed vblank events while interrupts where disabled
839            * based on system timestamps.
840            *
841            * Wraparound handling and loss of events due to modesetting is dealt
842            * with in the DRM core code, as long as drivers call
843            * drm_crtc_vblank_off() and drm_crtc_vblank_on() when disabling or
844            * enabling a CRTC.
845            *
846            * See also &drm_device.vblank_disable_immediate and
847            * &drm_device.max_vblank_count.
848            *
849            * Returns:
850            *
851            * Raw vblank counter value.
852            */
853           u32 (*get_vblank_counter)(struct drm_crtc *crtc);
854 
855           /**
856            * @enable_vblank:
857            *
858            * Enable vblank interrupts for the CRTC. It's meant to be used by
859            * new drivers as the replacement of &drm_driver.enable_vblank hook.
860            *
861            * Returns:
862            *
863            * Zero on success, appropriate errno if the vblank interrupt cannot
864            * be enabled.
865            */
866           int (*enable_vblank)(struct drm_crtc *crtc);
867 
868           /**
869            * @disable_vblank:
870            *
871            * Disable vblank interrupts for the CRTC. It's meant to be used by
872            * new drivers as the replacement of &drm_driver.disable_vblank hook.
873            */
874           void (*disable_vblank)(struct drm_crtc *crtc);
875 };
876 
877 /**
878  * struct drm_crtc - central CRTC control structure
879  *
880  * Each CRTC may have one or more connectors associated with it.  This structure
881  * allows the CRTC to be controlled.
882  */
883 struct drm_crtc {
884           /** @dev: parent DRM device */
885           struct drm_device *dev;
886           /** @port: OF node used by drm_of_find_possible_crtcs(). */
887           struct device_node *port;
888           /**
889            * @head:
890            *
891            * List of all CRTCs on @dev, linked from &drm_mode_config.crtc_list.
892            * Invariant over the lifetime of @dev and therefore does not need
893            * locking.
894            */
895           struct list_head head;
896 
897           /** @name: human readable name, can be overwritten by the driver */
898           char *name;
899 
900           /**
901            * @mutex:
902            *
903            * This provides a read lock for the overall CRTC state (mode, dpms
904            * state, ...) and a write lock for everything which can be update
905            * without a full modeset (fb, cursor data, CRTC properties ...). A full
906            * modeset also need to grab &drm_mode_config.connection_mutex.
907            *
908            * For atomic drivers specifically this protects @state.
909            */
910           struct drm_modeset_lock mutex;
911 
912           /** @base: base KMS object for ID tracking etc. */
913           struct drm_mode_object base;
914 
915           /**
916            * @primary:
917            * Primary plane for this CRTC. Note that this is only
918            * relevant for legacy IOCTL, it specifies the plane implicitly used by
919            * the SETCRTC and PAGE_FLIP IOCTLs. It does not have any significance
920            * beyond that.
921            */
922           struct drm_plane *primary;
923 
924           /**
925            * @cursor:
926            * Cursor plane for this CRTC. Note that this is only relevant for
927            * legacy IOCTL, it specifies the plane implicitly used by the SETCURSOR
928            * and SETCURSOR2 IOCTLs. It does not have any significance
929            * beyond that.
930            */
931           struct drm_plane *cursor;
932 
933           /**
934            * @index: Position inside the mode_config.list, can be used as an array
935            * index. It is invariant over the lifetime of the CRTC.
936            */
937           unsigned index;
938 
939           /**
940            * @cursor_x: Current x position of the cursor, used for universal
941            * cursor planes because the SETCURSOR IOCTL only can update the
942            * framebuffer without supplying the coordinates. Drivers should not use
943            * this directly, atomic drivers should look at &drm_plane_state.crtc_x
944            * of the cursor plane instead.
945            */
946           int cursor_x;
947           /**
948            * @cursor_y: Current y position of the cursor, used for universal
949            * cursor planes because the SETCURSOR IOCTL only can update the
950            * framebuffer without supplying the coordinates. Drivers should not use
951            * this directly, atomic drivers should look at &drm_plane_state.crtc_y
952            * of the cursor plane instead.
953            */
954           int cursor_y;
955 
956           /**
957            * @enabled:
958            *
959            * Is this CRTC enabled? Should only be used by legacy drivers, atomic
960            * drivers should instead consult &drm_crtc_state.enable and
961            * &drm_crtc_state.active. Atomic drivers can update this by calling
962            * drm_atomic_helper_update_legacy_modeset_state().
963            */
964           bool enabled;
965 
966           /**
967            * @mode:
968            *
969            * Current mode timings. Should only be used by legacy drivers, atomic
970            * drivers should instead consult &drm_crtc_state.mode. Atomic drivers
971            * can update this by calling
972            * drm_atomic_helper_update_legacy_modeset_state().
973            */
974           struct drm_display_mode mode;
975 
976           /**
977            * @hwmode:
978            *
979            * Programmed mode in hw, after adjustments for encoders, crtc, panel
980            * scaling etc. Should only be used by legacy drivers, for high
981            * precision vblank timestamps in
982            * drm_calc_vbltimestamp_from_scanoutpos().
983            *
984            * Note that atomic drivers should not use this, but instead use
985            * &drm_crtc_state.adjusted_mode. And for high-precision timestamps
986            * drm_calc_vbltimestamp_from_scanoutpos() used &drm_vblank_crtc.hwmode,
987            * which is filled out by calling drm_calc_timestamping_constants().
988            */
989           struct drm_display_mode hwmode;
990 
991           /**
992            * @x:
993            * x position on screen. Should only be used by legacy drivers, atomic
994            * drivers should look at &drm_plane_state.crtc_x of the primary plane
995            * instead. Updated by calling
996            * drm_atomic_helper_update_legacy_modeset_state().
997            */
998           int x;
999           /**
1000            * @y:
1001            * y position on screen. Should only be used by legacy drivers, atomic
1002            * drivers should look at &drm_plane_state.crtc_y of the primary plane
1003            * instead. Updated by calling
1004            * drm_atomic_helper_update_legacy_modeset_state().
1005            */
1006           int y;
1007 
1008           /** @funcs: CRTC control functions */
1009           const struct drm_crtc_funcs *funcs;
1010 
1011           /**
1012            * @gamma_size: Size of legacy gamma ramp reported to userspace. Set up
1013            * by calling drm_mode_crtc_set_gamma_size().
1014            */
1015           uint32_t gamma_size;
1016 
1017           /**
1018            * @gamma_store: Gamma ramp values used by the legacy SETGAMMA and
1019            * GETGAMMA IOCTls. Set up by calling drm_mode_crtc_set_gamma_size().
1020            */
1021           uint16_t *gamma_store;
1022 
1023           /** @helper_private: mid-layer private data */
1024           const struct drm_crtc_helper_funcs *helper_private;
1025 
1026           /** @properties: property tracking for this CRTC */
1027           struct drm_object_properties properties;
1028 
1029           /**
1030            * @state:
1031            *
1032            * Current atomic state for this CRTC.
1033            *
1034            * This is protected by @mutex. Note that nonblocking atomic commits
1035            * access the current CRTC state without taking locks. Either by going
1036            * through the &struct drm_atomic_state pointers, see
1037            * for_each_oldnew_crtc_in_state(), for_each_old_crtc_in_state() and
1038            * for_each_new_crtc_in_state(). Or through careful ordering of atomic
1039            * commit operations as implemented in the atomic helpers, see
1040            * &struct drm_crtc_commit.
1041            */
1042           struct drm_crtc_state *state;
1043 
1044           /**
1045            * @commit_list:
1046            *
1047            * List of &drm_crtc_commit structures tracking pending commits.
1048            * Protected by @commit_lock. This list holds its own full reference,
1049            * as does the ongoing commit.
1050            *
1051            * "Note that the commit for a state change is also tracked in
1052            * &drm_crtc_state.commit. For accessing the immediately preceding
1053            * commit in an atomic update it is recommended to just use that
1054            * pointer in the old CRTC state, since accessing that doesn't need
1055            * any locking or list-walking. @commit_list should only be used to
1056            * stall for framebuffer cleanup that's signalled through
1057            * &drm_crtc_commit.cleanup_done."
1058            */
1059           struct list_head commit_list;
1060 
1061           /**
1062            * @commit_lock:
1063            *
1064            * Spinlock to protect @commit_list.
1065            */
1066           spinlock_t commit_lock;
1067 
1068 #ifdef CONFIG_DEBUG_FS
1069           /**
1070            * @debugfs_entry:
1071            *
1072            * Debugfs directory for this CRTC.
1073            */
1074           struct dentry *debugfs_entry;
1075 #endif
1076 
1077           /**
1078            * @crc:
1079            *
1080            * Configuration settings of CRC capture.
1081            */
1082           struct drm_crtc_crc crc;
1083 
1084           /**
1085            * @fence_context:
1086            *
1087            * timeline context used for fence operations.
1088            */
1089           unsigned int fence_context;
1090 
1091           /**
1092            * @fence_lock:
1093            *
1094            * spinlock to protect the fences in the fence_context.
1095            */
1096           spinlock_t fence_lock;
1097           /**
1098            * @fence_seqno:
1099            *
1100            * Seqno variable used as monotonic counter for the fences
1101            * created on the CRTC's timeline.
1102            */
1103           unsigned long fence_seqno;
1104 
1105           /**
1106            * @timeline_name:
1107            *
1108            * The name of the CRTC's fence timeline.
1109            */
1110           char timeline_name[32];
1111 
1112           /**
1113            * @self_refresh_data: Holds the state for the self refresh helpers
1114            *
1115            * Initialized via drm_self_refresh_helper_init().
1116            */
1117           struct drm_self_refresh_data *self_refresh_data;
1118 };
1119 
1120 /**
1121  * struct drm_mode_set - new values for a CRTC config change
1122  * @fb: framebuffer to use for new config
1123  * @crtc: CRTC whose configuration we're about to change
1124  * @mode: mode timings to use
1125  * @x: position of this CRTC relative to @fb
1126  * @y: position of this CRTC relative to @fb
1127  * @connectors: array of connectors to drive with this CRTC if possible
1128  * @num_connectors: size of @connectors array
1129  *
1130  * This represents a modeset configuration for the legacy SETCRTC ioctl and is
1131  * also used internally. Atomic drivers instead use &drm_atomic_state.
1132  */
1133 struct drm_mode_set {
1134           struct drm_framebuffer *fb;
1135           struct drm_crtc *crtc;
1136           struct drm_display_mode *mode;
1137 
1138           uint32_t x;
1139           uint32_t y;
1140 
1141           struct drm_connector **connectors;
1142           size_t num_connectors;
1143 };
1144 
1145 #define obj_to_crtc(x) container_of(x, struct drm_crtc, base)
1146 
1147 __printf(6, 7)
1148 int drm_crtc_init_with_planes(struct drm_device *dev,
1149                                     struct drm_crtc *crtc,
1150                                     struct drm_plane *primary,
1151                                     struct drm_plane *cursor,
1152                                     const struct drm_crtc_funcs *funcs,
1153                                     const char *name, ...);
1154 void drm_crtc_cleanup(struct drm_crtc *crtc);
1155 
1156 /**
1157  * drm_crtc_index - find the index of a registered CRTC
1158  * @crtc: CRTC to find index for
1159  *
1160  * Given a registered CRTC, return the index of that CRTC within a DRM
1161  * device's list of CRTCs.
1162  */
drm_crtc_index(const struct drm_crtc * crtc)1163 static inline unsigned int drm_crtc_index(const struct drm_crtc *crtc)
1164 {
1165           return crtc->index;
1166 }
1167 
1168 /**
1169  * drm_crtc_mask - find the mask of a registered CRTC
1170  * @crtc: CRTC to find mask for
1171  *
1172  * Given a registered CRTC, return the mask bit of that CRTC for the
1173  * &drm_encoder.possible_crtcs and &drm_plane.possible_crtcs fields.
1174  */
drm_crtc_mask(const struct drm_crtc * crtc)1175 static inline uint32_t drm_crtc_mask(const struct drm_crtc *crtc)
1176 {
1177           return 1 << drm_crtc_index(crtc);
1178 }
1179 
1180 int drm_mode_set_config_internal(struct drm_mode_set *set);
1181 struct drm_crtc *drm_crtc_from_index(struct drm_device *dev, int idx);
1182 
1183 /**
1184  * drm_crtc_find - look up a CRTC object from its ID
1185  * @dev: DRM device
1186  * @file_priv: drm file to check for lease against.
1187  * @id: &drm_mode_object ID
1188  *
1189  * This can be used to look up a CRTC from its userspace ID. Only used by
1190  * drivers for legacy IOCTLs and interface, nowadays extensions to the KMS
1191  * userspace interface should be done using &drm_property.
1192  */
drm_crtc_find(struct drm_device * dev,struct drm_file * file_priv,uint32_t id)1193 static inline struct drm_crtc *drm_crtc_find(struct drm_device *dev,
1194                     struct drm_file *file_priv,
1195                     uint32_t id)
1196 {
1197           struct drm_mode_object *mo;
1198           mo = drm_mode_object_find(dev, file_priv, id, DRM_MODE_OBJECT_CRTC);
1199           return mo ? obj_to_crtc(mo) : NULL;
1200 }
1201 
1202 /**
1203  * drm_for_each_crtc - iterate over all CRTCs
1204  * @crtc: a &struct drm_crtc as the loop cursor
1205  * @dev: the &struct drm_device
1206  *
1207  * Iterate over all CRTCs of @dev.
1208  */
1209 #define drm_for_each_crtc(crtc, dev) \
1210           list_for_each_entry(crtc, &(dev)->mode_config.crtc_list, head)
1211 
1212 #endif /* __DRM_CRTC_H__ */
1213