drm: add drm_send_vblank_event() helper (v5)
A helper that drivers can use to send vblank event after a pageflip.
If the driver doesn't support proper vblank irq based time/seqn then
just pass -1 for the pipe # to get do_gettimestamp() behavior (since
there are a lot of drivers that don't use drm_vblank_count_and_time())
Also an internal send_vblank_event() helper for the various other code
paths within drm_irq that also need to send vblank events.
v1: original
v2: add back 'vblwait->reply.sequence = seq' which should not have
been deleted
v3: add WARN_ON() in case lock is not held and comments
v4: use WARN_ON_SMP() instead to fix issue with !SMP && !DEBUG_SPINLOCK
as pointed out by Marcin Slusarz
v5: update docbook
Signed-off-by: Rob Clark <rob@ti.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
diff --git a/Documentation/DocBook/drm.tmpl b/Documentation/DocBook/drm.tmpl
index b030052..c9cbb3f 100644
--- a/Documentation/DocBook/drm.tmpl
+++ b/Documentation/DocBook/drm.tmpl
@@ -1141,23 +1141,13 @@
the <methodname>page_flip</methodname> operation will be called with a
non-NULL <parameter>event</parameter> argument pointing to a
<structname>drm_pending_vblank_event</structname> instance. Upon page
- flip completion the driver must fill the
- <parameter>event</parameter>::<structfield>event</structfield>
- <structfield>sequence</structfield>, <structfield>tv_sec</structfield>
- and <structfield>tv_usec</structfield> fields with the associated
- vertical blanking count and timestamp, add the event to the
- <parameter>drm_file</parameter> list of events to be signaled, and wake
- up any waiting process. This can be performed with
+ flip completion the driver must call <methodname>drm_send_vblank_event</methodname>
+ to fill in the event and send to wake up any waiting processes.
+ This can be performed with
<programlisting><![CDATA[
- struct timeval now;
-
- event->event.sequence = drm_vblank_count_and_time(..., &now);
- event->event.tv_sec = now.tv_sec;
- event->event.tv_usec = now.tv_usec;
-
spin_lock_irqsave(&dev->event_lock, flags);
- list_add_tail(&event->base.link, &event->base.file_priv->event_list);
- wake_up_interruptible(&event->base.file_priv->event_wait);
+ ...
+ drm_send_vblank_event(dev, pipe, event);
spin_unlock_irqrestore(&dev->event_lock, flags);
]]></programlisting>
</para>
diff --git a/drivers/gpu/drm/drm_irq.c b/drivers/gpu/drm/drm_irq.c
index 3a3d0ce..44602ef 100644
--- a/drivers/gpu/drm/drm_irq.c
+++ b/drivers/gpu/drm/drm_irq.c
@@ -802,6 +802,46 @@
}
EXPORT_SYMBOL(drm_vblank_count_and_time);
+static void send_vblank_event(struct drm_device *dev,
+ struct drm_pending_vblank_event *e,
+ unsigned long seq, struct timeval *now)
+{
+ WARN_ON_SMP(!spin_is_locked(&dev->event_lock));
+ e->event.sequence = seq;
+ e->event.tv_sec = now->tv_sec;
+ e->event.tv_usec = now->tv_usec;
+
+ list_add_tail(&e->base.link,
+ &e->base.file_priv->event_list);
+ wake_up_interruptible(&e->base.file_priv->event_wait);
+ trace_drm_vblank_event_delivered(e->base.pid, e->pipe,
+ e->event.sequence);
+}
+
+/**
+ * drm_send_vblank_event - helper to send vblank event after pageflip
+ * @dev: DRM device
+ * @crtc: CRTC in question
+ * @e: the event to send
+ *
+ * Updates sequence # and timestamp on event, and sends it to userspace.
+ * Caller must hold event lock.
+ */
+void drm_send_vblank_event(struct drm_device *dev, int crtc,
+ struct drm_pending_vblank_event *e)
+{
+ struct timeval now;
+ unsigned int seq;
+ if (crtc >= 0) {
+ seq = drm_vblank_count_and_time(dev, crtc, &now);
+ } else {
+ seq = 0;
+ do_gettimeofday(&now);
+ }
+ send_vblank_event(dev, e, seq, &now);
+}
+EXPORT_SYMBOL(drm_send_vblank_event);
+
/**
* drm_update_vblank_count - update the master vblank counter
* @dev: DRM device
@@ -936,6 +976,13 @@
}
EXPORT_SYMBOL(drm_vblank_put);
+/**
+ * drm_vblank_off - disable vblank events on a CRTC
+ * @dev: DRM device
+ * @crtc: CRTC in question
+ *
+ * Caller must hold event lock.
+ */
void drm_vblank_off(struct drm_device *dev, int crtc)
{
struct drm_pending_vblank_event *e, *t;
@@ -955,15 +1002,9 @@
DRM_DEBUG("Sending premature vblank event on disable: \
wanted %d, current %d\n",
e->event.sequence, seq);
-
- e->event.sequence = seq;
- e->event.tv_sec = now.tv_sec;
- e->event.tv_usec = now.tv_usec;
+ list_del(&e->base.link);
drm_vblank_put(dev, e->pipe);
- list_move_tail(&e->base.link, &e->base.file_priv->event_list);
- wake_up_interruptible(&e->base.file_priv->event_wait);
- trace_drm_vblank_event_delivered(e->base.pid, e->pipe,
- e->event.sequence);
+ send_vblank_event(dev, e, seq, &now);
}
spin_unlock_irqrestore(&dev->vbl_lock, irqflags);
@@ -1107,15 +1148,9 @@
e->event.sequence = vblwait->request.sequence;
if ((seq - vblwait->request.sequence) <= (1 << 23)) {
- e->event.sequence = seq;
- e->event.tv_sec = now.tv_sec;
- e->event.tv_usec = now.tv_usec;
drm_vblank_put(dev, pipe);
- list_add_tail(&e->base.link, &e->base.file_priv->event_list);
- wake_up_interruptible(&e->base.file_priv->event_wait);
+ send_vblank_event(dev, e, seq, &now);
vblwait->reply.sequence = seq;
- trace_drm_vblank_event_delivered(current->pid, pipe,
- vblwait->request.sequence);
} else {
/* drm_handle_vblank_events will call drm_vblank_put */
list_add_tail(&e->base.link, &dev->vblank_event_list);
@@ -1256,14 +1291,9 @@
DRM_DEBUG("vblank event on %d, current %d\n",
e->event.sequence, seq);
- e->event.sequence = seq;
- e->event.tv_sec = now.tv_sec;
- e->event.tv_usec = now.tv_usec;
+ list_del(&e->base.link);
drm_vblank_put(dev, e->pipe);
- list_move_tail(&e->base.link, &e->base.file_priv->event_list);
- wake_up_interruptible(&e->base.file_priv->event_wait);
- trace_drm_vblank_event_delivered(e->base.pid, e->pipe,
- e->event.sequence);
+ send_vblank_event(dev, e, seq, &now);
}
spin_unlock_irqrestore(&dev->event_lock, flags);
diff --git a/include/drm/drmP.h b/include/drm/drmP.h
index 3fd8280..29eb237 100644
--- a/include/drm/drmP.h
+++ b/include/drm/drmP.h
@@ -1431,6 +1431,8 @@
extern u32 drm_vblank_count(struct drm_device *dev, int crtc);
extern u32 drm_vblank_count_and_time(struct drm_device *dev, int crtc,
struct timeval *vblanktime);
+extern void drm_send_vblank_event(struct drm_device *dev, int crtc,
+ struct drm_pending_vblank_event *e);
extern bool drm_handle_vblank(struct drm_device *dev, int crtc);
extern int drm_vblank_get(struct drm_device *dev, int crtc);
extern void drm_vblank_put(struct drm_device *dev, int crtc);
