diff options
Diffstat (limited to 'drivers/gpu/drm/drm_vblank.c')
| -rw-r--r-- | drivers/gpu/drm/drm_vblank.c | 60 |
1 files changed, 49 insertions, 11 deletions
diff --git a/drivers/gpu/drm/drm_vblank.c b/drivers/gpu/drm/drm_vblank.c index fd1fbc77871f..1659b13b178c 100644 --- a/drivers/gpu/drm/drm_vblank.c +++ b/drivers/gpu/drm/drm_vblank.c @@ -106,7 +106,7 @@ static void store_vblank(struct drm_device *dev, unsigned int pipe, write_seqlock(&vblank->seqlock); vblank->time = t_vblank; - vblank->count += vblank_count_inc; + atomic64_add(vblank_count_inc, &vblank->count); write_sequnlock(&vblank->seqlock); } @@ -272,7 +272,8 @@ static void drm_update_vblank_count(struct drm_device *dev, unsigned int pipe, DRM_DEBUG_VBL("updating vblank count on crtc %u:" " current=%llu, diff=%u, hw=%u hw_last=%u\n", - pipe, vblank->count, diff, cur_vblank, vblank->last); + pipe, atomic64_read(&vblank->count), diff, + cur_vblank, vblank->last); if (diff == 0) { WARN_ON_ONCE(cur_vblank != vblank->last); @@ -294,11 +295,23 @@ static void drm_update_vblank_count(struct drm_device *dev, unsigned int pipe, static u64 drm_vblank_count(struct drm_device *dev, unsigned int pipe) { struct drm_vblank_crtc *vblank = &dev->vblank[pipe]; + u64 count; if (WARN_ON(pipe >= dev->num_crtcs)) return 0; - return vblank->count; + count = atomic64_read(&vblank->count); + + /* + * This read barrier corresponds to the implicit write barrier of the + * write seqlock in store_vblank(). Note that this is the only place + * where we need an explicit barrier, since all other access goes + * through drm_vblank_count_and_time(), which already has the required + * read barrier curtesy of the read seqlock. + */ + smp_rmb(); + + return count; } /** @@ -319,7 +332,7 @@ u64 drm_crtc_accurate_vblank_count(struct drm_crtc *crtc) u64 vblank; unsigned long flags; - WARN_ONCE(drm_debug & DRM_UT_VBL && !dev->driver->get_vblank_timestamp, + WARN_ONCE(drm_debug_enabled(DRM_UT_VBL) && !dev->driver->get_vblank_timestamp, "This function requires support for accurate vblank timestamps."); spin_lock_irqsave(&dev->vblank_time_lock, flags); @@ -693,7 +706,7 @@ bool drm_calc_vbltimestamp_from_scanoutpos(struct drm_device *dev, */ *vblank_time = ktime_sub_ns(etime, delta_ns); - if ((drm_debug & DRM_UT_VBL) == 0) + if (!drm_debug_enabled(DRM_UT_VBL)) return true; ts_etime = ktime_to_timespec64(etime); @@ -763,6 +776,14 @@ drm_get_last_vbltimestamp(struct drm_device *dev, unsigned int pipe, * vblank interrupt (since it only reports the software vblank counter), see * drm_crtc_accurate_vblank_count() for such use-cases. * + * 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. + * + * See also &drm_vblank_crtc.count. + * * Returns: * The software vblank counter. */ @@ -800,7 +821,7 @@ static u64 drm_vblank_count_and_time(struct drm_device *dev, unsigned int pipe, do { seq = read_seqbegin(&vblank->seqlock); - vblank_count = vblank->count; + vblank_count = atomic64_read(&vblank->count); *vblanktime = vblank->time; } while (read_seqretry(&vblank->seqlock, seq)); @@ -817,6 +838,14 @@ static u64 drm_vblank_count_and_time(struct drm_device *dev, unsigned int pipe, * vblank events since the system was booted, including lost events due to * modesetting activity. Returns corresponding system timestamp of the time * of the vblank interval that corresponds to the current vblank counter value. + * + * 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. + * + * See also &drm_vblank_crtc.count. */ u64 drm_crtc_vblank_count_and_time(struct drm_crtc *crtc, ktime_t *vblanktime) @@ -1323,7 +1352,7 @@ void drm_vblank_restore(struct drm_device *dev, unsigned int pipe) assert_spin_locked(&dev->vblank_time_lock); vblank = &dev->vblank[pipe]; - WARN_ONCE((drm_debug & DRM_UT_VBL) && !vblank->framedur_ns, + WARN_ONCE(drm_debug_enabled(DRM_UT_VBL) && !vblank->framedur_ns, "Cannot compute missed vblanks without frame duration\n"); framedur_ns = vblank->framedur_ns; @@ -1581,7 +1610,7 @@ int drm_wait_vblank_ioctl(struct drm_device *dev, void *data, unsigned int flags, pipe, high_pipe; if (!dev->irq_enabled) - return -EINVAL; + return -EOPNOTSUPP; if (vblwait->request.type & _DRM_VBLANK_SIGNAL) return -EINVAL; @@ -1731,7 +1760,8 @@ static void drm_handle_vblank_events(struct drm_device *dev, unsigned int pipe) send_vblank_event(dev, e, seq, now); } - trace_drm_vblank_event(pipe, seq); + trace_drm_vblank_event(pipe, seq, now, + dev->driver->get_vblank_timestamp != NULL); } /** @@ -1806,6 +1836,14 @@ EXPORT_SYMBOL(drm_handle_vblank); * * This is the native KMS version of drm_handle_vblank(). * + * 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. + * + * See also &drm_vblank_crtc.count. + * * Returns: * True if the event was successfully handled, false on failure. */ @@ -1838,7 +1876,7 @@ int drm_crtc_get_sequence_ioctl(struct drm_device *dev, void *data, return -EOPNOTSUPP; if (!dev->irq_enabled) - return -EINVAL; + return -EOPNOTSUPP; crtc = drm_crtc_find(dev, file_priv, get_seq->crtc_id); if (!crtc) @@ -1896,7 +1934,7 @@ int drm_crtc_queue_sequence_ioctl(struct drm_device *dev, void *data, return -EOPNOTSUPP; if (!dev->irq_enabled) - return -EINVAL; + return -EOPNOTSUPP; crtc = drm_crtc_find(dev, file_priv, queue_seq->crtc_id); if (!crtc) |