/* * 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 <linux/kthread.h> #include <drm/drm_file.h> #include <drm/drm_modes.h> struct drm_device; struct drm_crtc; struct drm_vblank_work; /** * 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. * * Note that for a given vblank counter value drm_crtc_handle_vblank() * and drm_crtc_vblank_count() or drm_crtc_vblank_count_and_time() * provide a barrier: Any writes done before calling * drm_crtc_handle_vblank() will be visible to callers of the later * functions, iff the vblank count is the same or a later one. * * IMPORTANT: This guarantee requires barriers, therefor never access * this field directly. Use drm_crtc_vblank_count() instead. */ atomic64_t 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_crtc_vblank_helper_get_vblank_timestamp() and computed by * drm_calc_timestamping_constants(). */ int framedur_ns; /** * @linedur_ns: Line duration in ns, used by * drm_crtc_vblank_helper_get_vblank_timestamp() 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_crtc_vblank_helper_get_vblank_timestamp(). 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; /** * @worker: The &kthread_worker used for executing vblank works. */ struct kthread_worker *worker; /** * @pending_work: A list of scheduled &drm_vblank_work items that are * waiting for a future vblank. */ struct list_head pending_work; /** * @work_wait_queue: The wait queue used for signaling that a * &drm_vblank_work item has either finished executing, or was * cancelled. */ wait_queue_head_t work_wait_queue; }; int drm_vblank_init(struct drm_device *dev, unsigned int num_crtcs); bool drm_dev_has_vblank(const struct drm_device *dev); u64 drm_crtc_vblank_count(struct drm_crtc *crtc); u64 drm_crtc_vblank_count_and_time(struct drm_crtc *crtc, ktime_t *vblanktime); int drm_crtc_next_vblank_start(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_crtc_vblank_restore(struct drm_crtc *crtc); 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); /* * Helpers for struct drm_crtc_funcs */ typedef bool (*drm_vblank_get_scanout_position_func)(struct drm_crtc *crtc, bool in_vblank_irq, int *vpos, int *hpos, ktime_t *stime, ktime_t *etime, const struct drm_display_mode *mode); bool drm_crtc_vblank_helper_get_vblank_timestamp_internal(struct drm_crtc *crtc, int *max_error, ktime_t *vblank_time, bool in_vblank_irq, drm_vblank_get_scanout_position_func get_scanout_position); bool drm_crtc_vblank_helper_get_vblank_timestamp(struct drm_crtc *crtc, int *max_error, ktime_t *vblank_time, bool in_vblank_irq); #endif