[mirror_ubuntu-eoan-kernel.git] / include / drm / drm_vblank.h

/*
 * Copyright 2016 Intel Corp.
 *
 * Permission is hereby granted, free of charge, to any person obtaining a
 * copy of this software and associated documentation files (the "Software"),
 * to deal in the Software without restriction, including without limitation
 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
 * and/or sell copies of the Software, and to permit persons to whom the
 * Software is furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice (including the next
 * paragraph) shall be included in all copies or substantial portions of the
 * Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
 * VA LINUX SYSTEMS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM, DAMAGES OR
 * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
 * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
 * OTHER DEALINGS IN THE SOFTWARE.
 */

#ifndef _DRM_VBLANK_H_
#define _DRM_VBLANK_H_

#include <linux/seqlock.h>
#include <linux/idr.h>
#include <linux/poll.h>

#include <drm/drm_file.h>
#include <drm/drm_modes.h>
#include <uapi/drm/drm.h>

struct drm_device;
struct drm_crtc;

/**
 * struct drm_pending_vblank_event - pending vblank event tracking
 */
struct drm_pending_vblank_event {
	/**
	 * @base: Base structure for tracking pending DRM events.
	 */
	struct drm_pending_event base;
	/**
	 * @pipe: drm_crtc_index() of the &drm_crtc this event is for.
	 */
	unsigned int pipe;
	/**
	 * @sequence: frame event should be triggered at
	 */
	u64 sequence;
	/**
	 * @event: Actual event which will be sent to userspace.
	 */
	union {
		/**
		 * @event.base: DRM event base class.
		 */
		struct drm_event base;

		/**
		 * @event.vbl:
		 *
		 * Event payload for vblank events, requested through
		 * either the MODE_PAGE_FLIP or MODE_ATOMIC IOCTL. Also
		 * generated by the legacy WAIT_VBLANK IOCTL, but new userspace
		 * should use MODE_QUEUE_SEQUENCE and &event.seq instead.
		 */
		struct drm_event_vblank vbl;

		/**
		 * @event.seq: Event payload for the MODE_QUEUEU_SEQUENCE IOCTL.
		 */
		struct drm_event_crtc_sequence seq;
	} event;
};

/**
 * struct drm_vblank_crtc - vblank tracking for a CRTC
 *
 * This structure tracks the vblank state for one CRTC.
 *
 * Note that for historical reasons - the vblank handling code is still shared
 * with legacy/non-kms drivers - this is a free-standing structure not directly
 * connected to &struct drm_crtc. But all public interface functions are taking
 * a &struct drm_crtc to hide this implementation detail.
 */
struct drm_vblank_crtc {
	/**
	 * @dev: Pointer to the &drm_device.
	 */
	struct drm_device *dev;
	/**
	 * @queue: Wait queue for vblank waiters.
	 */
	wait_queue_head_t queue;
	/**
	 * @disable_timer: Disable timer for the delayed vblank disabling
	 * hysteresis logic. Vblank disabling is controlled through the
	 * drm_vblank_offdelay module option and the setting of the
	 * &drm_device.max_vblank_count value.
	 */
	struct timer_list disable_timer;

	/**
	 * @seqlock: Protect vblank count and time.
	 */
	seqlock_t seqlock;

	/**
	 * @count: Current software vblank counter.
	 */
	u64 count;
	/**
	 * @time: Vblank timestamp corresponding to @count.
	 */
	ktime_t time;

	/**
	 * @refcount: Number of users/waiters of the vblank interrupt. Only when
	 * this refcount reaches 0 can the hardware interrupt be disabled using
	 * @disable_timer.
	 */
	atomic_t refcount;
	/**
	 * @last: Protected by &drm_device.vbl_lock, used for wraparound handling.
	 */
	u32 last;
	/**
	 * @max_vblank_count:
	 *
	 * Maximum value of the vblank registers for this crtc. This value +1
	 * will result in a wrap-around of the vblank register. It is used
	 * by the vblank core to handle wrap-arounds.
	 *
	 * If set to zero the vblank core will try to guess the elapsed vblanks
	 * between times when the vblank interrupt is disabled through
	 * high-precision timestamps. That approach is suffering from small
	 * races and imprecision over longer time periods, hence exposing a
	 * hardware vblank counter is always recommended.
	 *
	 * This is the runtime configurable per-crtc maximum set through
	 * drm_crtc_set_max_vblank_count(). If this is used the driver
	 * must leave the device wide &drm_device.max_vblank_count at zero.
	 *
	 * If non-zero, &drm_crtc_funcs.get_vblank_counter must be set.
	 */
	u32 max_vblank_count;
	/**
	 * @inmodeset: Tracks whether the vblank is disabled due to a modeset.
	 * For legacy driver bit 2 additionally tracks whether an additional
	 * temporary vblank reference has been acquired to paper over the
	 * hardware counter resetting/jumping. KMS drivers should instead just
	 * call drm_crtc_vblank_off() and drm_crtc_vblank_on(), which explicitly
	 * save and restore the vblank count.
	 */
	unsigned int inmodeset;
	/**
	 * @pipe: drm_crtc_index() of the &drm_crtc corresponding to this
	 * structure.
	 */
	unsigned int pipe;
	/**
	 * @framedur_ns: Frame/Field duration in ns, used by
	 * drm_calc_vbltimestamp_from_scanoutpos() and computed by
	 * drm_calc_timestamping_constants().
	 */
	int framedur_ns;
	/**
	 * @linedur_ns: Line duration in ns, used by
	 * drm_calc_vbltimestamp_from_scanoutpos() and computed by
	 * drm_calc_timestamping_constants().
	 */
	int linedur_ns;

	/**
	 * @hwmode:
	 *
	 * Cache of the current hardware display mode. Only valid when @enabled
	 * is set. This is used by helpers like
	 * drm_calc_vbltimestamp_from_scanoutpos(). We can't just access the
	 * hardware mode by e.g. looking at &drm_crtc_state.adjusted_mode,
	 * because that one is really hard to get from interrupt context.
	 */
	struct drm_display_mode hwmode;

	/**
	 * @enabled: Tracks the enabling state of the corresponding &drm_crtc to
	 * avoid double-disabling and hence corrupting saved state. Needed by
	 * drivers not using atomic KMS, since those might go through their CRTC
	 * disabling functions multiple times.
	 */
	bool enabled;
};

int drm_vblank_init(struct drm_device *dev, unsigned int num_crtcs);
u64 drm_crtc_vblank_count(struct drm_crtc *crtc);
u64 drm_crtc_vblank_count_and_time(struct drm_crtc *crtc,
				   ktime_t *vblanktime);
void drm_crtc_send_vblank_event(struct drm_crtc *crtc,
			       struct drm_pending_vblank_event *e);
void drm_crtc_arm_vblank_event(struct drm_crtc *crtc,
			      struct drm_pending_vblank_event *e);
void drm_vblank_set_event(struct drm_pending_vblank_event *e,
			  u64 *seq,
			  ktime_t *now);
bool drm_handle_vblank(struct drm_device *dev, unsigned int pipe);
bool drm_crtc_handle_vblank(struct drm_crtc *crtc);
int drm_crtc_vblank_get(struct drm_crtc *crtc);
void drm_crtc_vblank_put(struct drm_crtc *crtc);
void drm_wait_one_vblank(struct drm_device *dev, unsigned int pipe);
void drm_crtc_wait_one_vblank(struct drm_crtc *crtc);
void drm_crtc_vblank_off(struct drm_crtc *crtc);
void drm_crtc_vblank_reset(struct drm_crtc *crtc);
void drm_crtc_vblank_on(struct drm_crtc *crtc);
u64 drm_crtc_accurate_vblank_count(struct drm_crtc *crtc);
void drm_vblank_restore(struct drm_device *dev, unsigned int pipe);
void drm_crtc_vblank_restore(struct drm_crtc *crtc);

bool drm_calc_vbltimestamp_from_scanoutpos(struct drm_device *dev,
					   unsigned int pipe, int *max_error,
					   ktime_t *vblank_time,
					   bool in_vblank_irq);
void drm_calc_timestamping_constants(struct drm_crtc *crtc,
				     const struct drm_display_mode *mode);
wait_queue_head_t *drm_crtc_vblank_waitqueue(struct drm_crtc *crtc);
void drm_crtc_set_max_vblank_count(struct drm_crtc *crtc,
				   u32 max_vblank_count);
#endif
Commit	Line	Data
3ed4351a DV	1	/*
	2	* Copyright 2016 Intel Corp.
	3	*
	4	* Permission is hereby granted, free of charge, to any person obtaining a
	5	* copy of this software and associated documentation files (the "Software"),
	6	* to deal in the Software without restriction, including without limitation
	7	* the rights to use, copy, modify, merge, publish, distribute, sublicense,
	8	* and/or sell copies of the Software, and to permit persons to whom the
	9	* Software is furnished to do so, subject to the following conditions:
	10	*
	11	* The above copyright notice and this permission notice (including the next
	12	* paragraph) shall be included in all copies or substantial portions of the
	13	* Software.
	14	*
	15	* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
	16	* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
	17	* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
	18	* VA LINUX SYSTEMS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM, DAMAGES OR
	19	* OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
	20	* ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
	21	* OTHER DEALINGS IN THE SOFTWARE.
	22	*/
	23
	24	#ifndef _DRM_VBLANK_H_
	25	#define _DRM_VBLANK_H_
	26
	27	#include <linux/seqlock.h>
	28	#include <linux/idr.h>
	29	#include <linux/poll.h>
	30
	31	#include <drm/drm_file.h>
	32	#include <drm/drm_modes.h>
	33	#include <uapi/drm/drm.h>
	34
	35	struct drm_device;
	36	struct drm_crtc;
	37
	38	/**
	39	* struct drm_pending_vblank_event - pending vblank event tracking
	40	*/
	41	struct drm_pending_vblank_event {
	42	/**
	43	* @base: Base structure for tracking pending DRM events.
	44	*/
	45	struct drm_pending_event base;
	46	/**
	47	* @pipe: drm_crtc_index() of the &drm_crtc this event is for.
	48	*/
	49	unsigned int pipe;
570e8696 KP	50	/**
	51	* @sequence: frame event should be triggered at
	52	*/
	53	u64 sequence;
3ed4351a DV	54	/**
	55	* @event: Actual event which will be sent to userspace.
	56	*/
bd386e51	57	union {
83a7dff0 DV	58	/**
	59	* @event.base: DRM event base class.
	60	*/
bd386e51	61	struct drm_event base;
83a7dff0 DV	62
	63	/**
	64	* @event.vbl:
	65	*
	66	* Event payload for vblank events, requested through
	67	* either the MODE_PAGE_FLIP or MODE_ATOMIC IOCTL. Also
	68	* generated by the legacy WAIT_VBLANK IOCTL, but new userspace
	69	* should use MODE_QUEUE_SEQUENCE and &event.seq instead.
	70	*/
bd386e51	71	struct drm_event_vblank vbl;
83a7dff0 DV	72
	73	/**
	74	* @event.seq: Event payload for the MODE_QUEUEU_SEQUENCE IOCTL.
	75	*/
3064abfa	76	struct drm_event_crtc_sequence seq;
bd386e51	77	} event;
3ed4351a DV	78	};
	79
	80	/**
	81	* struct drm_vblank_crtc - vblank tracking for a CRTC
	82	*
	83	* This structure tracks the vblank state for one CRTC.
	84	*
	85	* Note that for historical reasons - the vblank handling code is still shared
	86	* with legacy/non-kms drivers - this is a free-standing structure not directly
	87	* connected to &struct drm_crtc. But all public interface functions are taking
	88	* a &struct drm_crtc to hide this implementation detail.
	89	*/
	90	struct drm_vblank_crtc {
	91	/**
	92	* @dev: Pointer to the &drm_device.
	93	*/
	94	struct drm_device *dev;
	95	/**
	96	* @queue: Wait queue for vblank waiters.
	97	*/
9e37ee79	98	wait_queue_head_t queue;
3ed4351a DV	99	/**
	100	* @disable_timer: Disable timer for the delayed vblank disabling
	101	* hysteresis logic. Vblank disabling is controlled through the
	102	* drm_vblank_offdelay module option and the setting of the
	103	* &drm_device.max_vblank_count value.
	104	*/
	105	struct timer_list disable_timer;
	106
	107	/**
	108	* @seqlock: Protect vblank count and time.
	109	*/
9e37ee79	110	seqlock_t seqlock;
3ed4351a DV	111
	112	/**
	113	* @count: Current software vblank counter.
	114	*/
570e8696	115	u64 count;
3ed4351a DV	116	/**
	117	* @time: Vblank timestamp corresponding to @count.
	118	*/
67680d3c	119	ktime_t time;
3ed4351a DV	120
	121	/**
	122	* @refcount: Number of users/waiters of the vblank interrupt. Only when
	123	* this refcount reaches 0 can the hardware interrupt be disabled using
	124	* @disable_timer.
	125	*/
9e37ee79	126	atomic_t refcount;
3ed4351a DV	127	/**
	128	* @last: Protected by &drm_device.vbl_lock, used for wraparound handling.
	129	*/
	130	u32 last;
ed20151a VS	131	/**
	132	* @max_vblank_count:
	133	*
	134	* Maximum value of the vblank registers for this crtc. This value +1
	135	* will result in a wrap-around of the vblank register. It is used
	136	* by the vblank core to handle wrap-arounds.
	137	*
	138	* If set to zero the vblank core will try to guess the elapsed vblanks
	139	* between times when the vblank interrupt is disabled through
	140	* high-precision timestamps. That approach is suffering from small
	141	* races and imprecision over longer time periods, hence exposing a
	142	* hardware vblank counter is always recommended.
	143	*
	144	* This is the runtime configurable per-crtc maximum set through
	145	* drm_crtc_set_max_vblank_count(). If this is used the driver
	146	* must leave the device wide &drm_device.max_vblank_count at zero.
	147	*
	148	* If non-zero, &drm_crtc_funcs.get_vblank_counter must be set.
	149	*/
	150	u32 max_vblank_count;
3ed4351a DV	151	/**
	152	* @inmodeset: Tracks whether the vblank is disabled due to a modeset.
	153	* For legacy driver bit 2 additionally tracks whether an additional
	154	* temporary vblank reference has been acquired to paper over the
	155	* hardware counter resetting/jumping. KMS drivers should instead just
	156	* call drm_crtc_vblank_off() and drm_crtc_vblank_on(), which explicitly
	157	* save and restore the vblank count.
	158	*/
9e37ee79	159	unsigned int inmodeset;
3ed4351a DV	160	/**
	161	* @pipe: drm_crtc_index() of the &drm_crtc corresponding to this
	162	* structure.
	163	*/
	164	unsigned int pipe;
	165	/**
	166	* @framedur_ns: Frame/Field duration in ns, used by
	167	* drm_calc_vbltimestamp_from_scanoutpos() and computed by
	168	* drm_calc_timestamping_constants().
	169	*/
	170	int framedur_ns;
	171	/**
	172	* @linedur_ns: Line duration in ns, used by
	173	* drm_calc_vbltimestamp_from_scanoutpos() and computed by
	174	* drm_calc_timestamping_constants().
	175	*/
	176	int linedur_ns;
	177
	178	/**
	179	* @hwmode:
	180	*
	181	* Cache of the current hardware display mode. Only valid when @enabled
	182	* is set. This is used by helpers like
	183	* drm_calc_vbltimestamp_from_scanoutpos(). We can't just access the
	184	* hardware mode by e.g. looking at &drm_crtc_state.adjusted_mode,
	185	* because that one is really hard to get from interrupt context.
	186	*/
	187	struct drm_display_mode hwmode;
	188
	189	/**
	190	* @enabled: Tracks the enabling state of the corresponding &drm_crtc to
	191	* avoid double-disabling and hence corrupting saved state. Needed by
	192	* drivers not using atomic KMS, since those might go through their CRTC
	193	* disabling functions multiple times.
	194	*/
	195	bool enabled;
	196	};
	197
	198	int drm_vblank_init(struct drm_device *dev, unsigned int num_crtcs);
570e8696 KP	199	u64 drm_crtc_vblank_count(struct drm_crtc *crtc);
570e8696 KP	200	u64 drm_crtc_vblank_count_and_time(struct drm_crtc *crtc,
67680d3c	201	ktime_t *vblanktime);
3ed4351a DV	202	void drm_crtc_send_vblank_event(struct drm_crtc *crtc,
	203	struct drm_pending_vblank_event *e);
	204	void drm_crtc_arm_vblank_event(struct drm_crtc *crtc,
	205	struct drm_pending_vblank_event *e);
bd386e51 KP	206	void drm_vblank_set_event(struct drm_pending_vblank_event *e,
	207	u64 *seq,
	208	ktime_t *now);
3ed4351a DV	209	bool drm_handle_vblank(struct drm_device *dev, unsigned int pipe);
	210	bool drm_crtc_handle_vblank(struct drm_crtc *crtc);
	211	int drm_crtc_vblank_get(struct drm_crtc *crtc);
	212	void drm_crtc_vblank_put(struct drm_crtc *crtc);
	213	void drm_wait_one_vblank(struct drm_device *dev, unsigned int pipe);
	214	void drm_crtc_wait_one_vblank(struct drm_crtc *crtc);
	215	void drm_crtc_vblank_off(struct drm_crtc *crtc);
	216	void drm_crtc_vblank_reset(struct drm_crtc *crtc);
	217	void drm_crtc_vblank_on(struct drm_crtc *crtc);
3b765c0b	218	u64 drm_crtc_accurate_vblank_count(struct drm_crtc *crtc);
d0bb96b4 DP	219	void drm_vblank_restore(struct drm_device *dev, unsigned int pipe);
d0bb96b4 DP	220	void drm_crtc_vblank_restore(struct drm_crtc *crtc);
3ed4351a DV	221
	222	bool drm_calc_vbltimestamp_from_scanoutpos(struct drm_device *dev,
	223	unsigned int pipe, int *max_error,
67680d3c	224	ktime_t *vblank_time,
3ed4351a DV	225	bool in_vblank_irq);
	226	void drm_calc_timestamping_constants(struct drm_crtc *crtc,
	227	const struct drm_display_mode *mode);
	228	wait_queue_head_t drm_crtc_vblank_waitqueue(struct drm_crtc crtc);
ed20151a VS	229	void drm_crtc_set_max_vblank_count(struct drm_crtc *crtc,
ed20151a VS	230	u32 max_vblank_count);
3ed4351a	231	#endif