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path: root/drivers/gpu/drm/drm_irq.c
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Diffstat (limited to 'drivers/gpu/drm/drm_irq.c')
-rw-r--r--drivers/gpu/drm/drm_irq.c90
1 files changed, 61 insertions, 29 deletions
diff --git a/drivers/gpu/drm/drm_irq.c b/drivers/gpu/drm/drm_irq.c
index 53a526c7b24d..dac1b2593cb1 100644
--- a/drivers/gpu/drm/drm_irq.c
+++ b/drivers/gpu/drm/drm_irq.c
@@ -325,6 +325,8 @@ static void vblank_disable_and_save(struct drm_device *dev, unsigned int pipe)
struct drm_vblank_crtc *vblank = &dev->vblank[pipe];
unsigned long irqflags;
+ assert_spin_locked(&dev->vbl_lock);
+
/* Prevent vblank irq processing while disabling vblank irqs,
* so no updates of timestamps or count can happen after we've
* disabled. Needed to prevent races in case of delayed irq's.
@@ -384,7 +386,7 @@ void drm_vblank_cleanup(struct drm_device *dev)
for (pipe = 0; pipe < dev->num_crtcs; pipe++) {
struct drm_vblank_crtc *vblank = &dev->vblank[pipe];
- WARN_ON(vblank->enabled &&
+ WARN_ON(READ_ONCE(vblank->enabled) &&
drm_core_check_feature(dev, DRIVER_MODESET));
del_timer_sync(&vblank->disable_timer);
@@ -810,14 +812,6 @@ int drm_calc_vbltimestamp_from_scanoutpos(struct drm_device *dev,
/* Return upper bound of timestamp precision error. */
*max_error = duration_ns;
- /* Check if in vblank area:
- * vpos is >=0 in video scanout area, but negative
- * within vblank area, counting down the number of lines until
- * start of scanout.
- */
- if (vbl_status & DRM_SCANOUTPOS_IN_VBLANK)
- ret |= DRM_VBLANKTIME_IN_VBLANK;
-
/* Convert scanout position into elapsed time at raw_time query
* since start of scanout at first display scanline. delta_ns
* can be negative if start of scanout hasn't happened yet.
@@ -1105,11 +1099,16 @@ static int drm_vblank_enable(struct drm_device *dev, unsigned int pipe)
*/
ret = __enable_vblank(dev, pipe);
DRM_DEBUG("enabling vblank on crtc %u, ret: %d\n", pipe, ret);
- if (ret)
+ if (ret) {
atomic_dec(&vblank->refcount);
- else {
- vblank->enabled = true;
+ } else {
drm_update_vblank_count(dev, pipe, 0);
+ /* drm_update_vblank_count() includes a wmb so we just
+ * need to ensure that the compiler emits the write
+ * to mark the vblank as enabled after the call
+ * to drm_update_vblank_count().
+ */
+ WRITE_ONCE(vblank->enabled, true);
}
}
@@ -1487,6 +1486,11 @@ int drm_legacy_modeset_ctl(struct drm_device *dev, void *data,
return 0;
}
+static inline bool vblank_passed(u32 seq, u32 ref)
+{
+ return (seq - ref) <= (1 << 23);
+}
+
static int drm_queue_vblank_event(struct drm_device *dev, unsigned int pipe,
union drm_wait_vblank *vblwait,
struct drm_file *file_priv)
@@ -1517,7 +1521,7 @@ static int drm_queue_vblank_event(struct drm_device *dev, unsigned int pipe,
* vblank disable, so no need for further locking. The reference from
* drm_vblank_get() protects against vblank disable from another source.
*/
- if (!vblank->enabled) {
+ if (!READ_ONCE(vblank->enabled)) {
ret = -EINVAL;
goto err_unlock;
}
@@ -1537,7 +1541,7 @@ static int drm_queue_vblank_event(struct drm_device *dev, unsigned int pipe,
vblwait->request.sequence);
e->event.sequence = vblwait->request.sequence;
- if ((seq - vblwait->request.sequence) <= (1 << 23)) {
+ if (vblank_passed(seq, vblwait->request.sequence)) {
drm_vblank_put(dev, pipe);
send_vblank_event(dev, e, seq, &now);
vblwait->reply.sequence = seq;
@@ -1559,6 +1563,17 @@ err_put:
return ret;
}
+static bool drm_wait_vblank_is_query(union drm_wait_vblank *vblwait)
+{
+ if (vblwait->request.sequence)
+ return false;
+
+ return _DRM_VBLANK_RELATIVE ==
+ (vblwait->request.type & (_DRM_VBLANK_TYPES_MASK |
+ _DRM_VBLANK_EVENT |
+ _DRM_VBLANK_NEXTONMISS));
+}
+
/*
* Wait for VBLANK.
*
@@ -1608,6 +1623,21 @@ int drm_wait_vblank(struct drm_device *dev, void *data,
vblank = &dev->vblank[pipe];
+ /* If the counter is currently enabled and accurate, short-circuit
+ * queries to return the cached timestamp of the last vblank.
+ */
+ if (dev->vblank_disable_immediate &&
+ drm_wait_vblank_is_query(vblwait) &&
+ READ_ONCE(vblank->enabled)) {
+ struct timeval now;
+
+ vblwait->reply.sequence =
+ drm_vblank_count_and_time(dev, pipe, &now);
+ vblwait->reply.tval_sec = now.tv_sec;
+ vblwait->reply.tval_usec = now.tv_usec;
+ return 0;
+ }
+
ret = drm_vblank_get(dev, pipe);
if (ret) {
DRM_DEBUG("crtc %d failed to acquire vblank counter, %d\n", pipe, ret);
@@ -1627,9 +1657,8 @@ int drm_wait_vblank(struct drm_device *dev, void *data,
}
if ((flags & _DRM_VBLANK_NEXTONMISS) &&
- (seq - vblwait->request.sequence) <= (1 << 23)) {
+ vblank_passed(seq, vblwait->request.sequence))
vblwait->request.sequence = seq + 1;
- }
if (flags & _DRM_VBLANK_EVENT) {
/* must hold on to the vblank ref until the event fires
@@ -1642,10 +1671,9 @@ int drm_wait_vblank(struct drm_device *dev, void *data,
DRM_DEBUG("waiting on vblank count %u, crtc %u\n",
vblwait->request.sequence, pipe);
DRM_WAIT_ON(ret, vblank->queue, 3 * HZ,
- (((drm_vblank_count(dev, pipe) -
- vblwait->request.sequence) <= (1 << 23)) ||
- !vblank->enabled ||
- !dev->irq_enabled));
+ vblank_passed(drm_vblank_count(dev, pipe),
+ vblwait->request.sequence) ||
+ !READ_ONCE(vblank->enabled));
}
if (ret != -EINTR) {
@@ -1679,7 +1707,7 @@ static void drm_handle_vblank_events(struct drm_device *dev, unsigned int pipe)
list_for_each_entry_safe(e, t, &dev->vblank_event_list, base.link) {
if (e->pipe != pipe)
continue;
- if ((seq - e->event.sequence) > (1<<23))
+ if (!vblank_passed(seq, e->event.sequence))
continue;
DRM_DEBUG("vblank event on %u, current %u\n",
@@ -1707,6 +1735,7 @@ bool drm_handle_vblank(struct drm_device *dev, unsigned int pipe)
{
struct drm_vblank_crtc *vblank = &dev->vblank[pipe];
unsigned long irqflags;
+ bool disable_irq;
if (WARN_ON_ONCE(!dev->num_crtcs))
return false;
@@ -1734,20 +1763,23 @@ bool drm_handle_vblank(struct drm_device *dev, unsigned int pipe)
spin_unlock(&dev->vblank_time_lock);
wake_up(&vblank->queue);
- drm_handle_vblank_events(dev, pipe);
/* With instant-off, we defer disabling the interrupt until after
- * we finish processing the following vblank. The disable has to
- * be last (after drm_handle_vblank_events) so that the timestamp
- * is always accurate.
+ * we finish processing the following vblank after all events have
+ * been signaled. The disable has to be last (after
+ * drm_handle_vblank_events) so that the timestamp is always accurate.
*/
- if (dev->vblank_disable_immediate &&
- drm_vblank_offdelay > 0 &&
- !atomic_read(&vblank->refcount))
- vblank_disable_fn((unsigned long)vblank);
+ disable_irq = (dev->vblank_disable_immediate &&
+ drm_vblank_offdelay > 0 &&
+ !atomic_read(&vblank->refcount));
+
+ drm_handle_vblank_events(dev, pipe);
spin_unlock_irqrestore(&dev->event_lock, irqflags);
+ if (disable_irq)
+ vblank_disable_fn((unsigned long)vblank);
+
return true;
}
EXPORT_SYMBOL(drm_handle_vblank);
generated by cgit v1.2.3 (git 2.39.1) at 2024-09-06 15:18:51 +0000