v4.19.13 snapshot.
diff --git a/include/drm/drm_vblank.h b/include/drm/drm_vblank.h
new file mode 100644
index 0000000..d25a960
--- /dev/null
+++ b/include/drm/drm_vblank.h
@@ -0,0 +1,209 @@
+/*
+ * 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; /**< VBLANK wait 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; /* protects vblank count and time */
+
+ /**
+ * @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; /* number of users of vblank interruptsper crtc */
+ /**
+ * @last: Protected by &drm_device.vbl_lock, used for wraparound handling.
+ */
+ u32 last;
+ /**
+ * @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; /* Display driver is setting mode */
+ /**
+ * @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);
+#endif