<div dir="ltr"><div>LGTM. This one is</div><div> </div><div>Reviewed-by: Mario Kleiner <<a href="mailto:mario.kleiner.de@gmail.com">mario.kleiner.de@gmail.com</a>></div><div> </div><div>-mario</div><div> </div></div> <div class="gmail_quote"><div dir="ltr" class="gmail_attr">On Mon, Feb 27, 2023 at 8:36 PM Rob Clark <<a href="mailto:robdclark@gmail.com">robdclark@gmail.com</a>> wrote: </div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex">From: Rob Clark <<a href="mailto:robdclark@chromium.org" target="_blank">robdclark@chromium.org</a>> Will be used in the next commit to set a deadline on fences that an atomic update is waiting on. v2: Calculate time at *start* of vblank period, not end v3: Fix kbuild complaints Signed-off-by: Rob Clark <<a href="mailto:robdclark@chromium.org" target="_blank">robdclark@chromium.org</a>> --- drivers/gpu/drm/drm_vblank.c | 53 ++++++++++++++++++++++++++++++------ include/drm/drm_vblank.h | 1 + 2 files changed, 45 insertions(+), 9 deletions(-) diff --git a/drivers/gpu/drm/drm_vblank.c b/drivers/gpu/drm/drm_vblank.c index 2ff31717a3de..299fa2a19a90 100644 --- a/drivers/gpu/drm/drm_vblank.c +++ b/drivers/gpu/drm/drm_vblank.c @@ -844,10 +844,9 @@ bool drm_crtc_vblank_helper_get_vblank_timestamp(struct drm_crtc *crtc, EXPORT_SYMBOL(drm_crtc_vblank_helper_get_vblank_timestamp); /** - * drm_get_last_vbltimestamp - retrieve raw timestamp for the most recent - * vblank interval - * @dev: DRM device - * @pipe: index of CRTC whose vblank timestamp to retrieve + * drm_crtc_get_last_vbltimestamp - retrieve raw timestamp for the most + * recent vblank interval + * @crtc: CRTC whose vblank timestamp to retrieve * @tvblank: Pointer to target time which should receive the timestamp * @in_vblank_irq: * True when called from drm_crtc_handle_vblank(). Some drivers @@ -865,10 +864,9 @@ EXPORT_SYMBOL(drm_crtc_vblank_helper_get_vblank_timestamp); * True if timestamp is considered to be very precise, false otherwise. */ static bool -drm_get_last_vbltimestamp(struct drm_device *dev, unsigned int pipe, - ktime_t *tvblank, bool in_vblank_irq) +drm_crtc_get_last_vbltimestamp(struct drm_crtc *crtc, ktime_t *tvblank, + bool in_vblank_irq) { - struct drm_crtc *crtc = drm_crtc_from_index(dev, pipe); bool ret = false; /* Define requested maximum error on timestamps (nanoseconds). */ @@ -876,8 +874,6 @@ drm_get_last_vbltimestamp(struct drm_device *dev, unsigned int pipe, /* Query driver if possible and precision timestamping enabled. */ if (crtc && crtc->funcs->get_vblank_timestamp && max_error > 0) { - struct drm_crtc *crtc = drm_crtc_from_index(dev, pipe); - ret = crtc->funcs->get_vblank_timestamp(crtc, &max_error, tvblank, in_vblank_irq); } @@ -891,6 +887,15 @@ drm_get_last_vbltimestamp(struct drm_device *dev, unsigned int pipe, return ret; } +static bool +drm_get_last_vbltimestamp(struct drm_device *dev, unsigned int pipe, + ktime_t *tvblank, bool in_vblank_irq) +{ + struct drm_crtc *crtc = drm_crtc_from_index(dev, pipe); + + return drm_crtc_get_last_vbltimestamp(crtc, tvblank, in_vblank_irq); +} + /** * drm_crtc_vblank_count - retrieve "cooked" vblank counter value * @crtc: which counter to retrieve @@ -980,6 +985,36 @@ u64 drm_crtc_vblank_count_and_time(struct drm_crtc *crtc, } EXPORT_SYMBOL(drm_crtc_vblank_count_and_time); +/** + * drm_crtc_next_vblank_start - calculate the time of the next vblank + * @crtc: the crtc for which to calculate next vblank time + * @vblanktime: pointer to time to receive the next vblank timestamp. + * + * Calculate the expected time of the start of the next vblank period, + * based on time of previous vblank and frame duration + */ +int drm_crtc_next_vblank_start(struct drm_crtc *crtc, ktime_t *vblanktime) +{ + unsigned int pipe = drm_crtc_index(crtc); + struct drm_vblank_crtc *vblank = &crtc->dev->vblank[pipe]; + struct drm_display_mode *mode = &vblank->hwmode; + u64 vblank_start; + + if (!vblank->framedur_ns || !vblank->linedur_ns) + return -EINVAL; + + if (!drm_crtc_get_last_vbltimestamp(crtc, vblanktime, false)) + return -EINVAL; + + vblank_start = DIV_ROUND_DOWN_ULL( + (u64)vblank->framedur_ns * mode->crtc_vblank_start, + mode->crtc_vtotal); + *vblanktime = ktime_add(*vblanktime, ns_to_ktime(vblank_start)); + + return 0; +} +EXPORT_SYMBOL(drm_crtc_next_vblank_start); + static void send_vblank_event(struct drm_device *dev, struct drm_pending_vblank_event *e, u64 seq, ktime_t now) diff --git a/include/drm/drm_vblank.h b/include/drm/drm_vblank.h index 733a3e2d1d10..7f3957943dd1 100644 --- a/include/drm/drm_vblank.h +++ b/include/drm/drm_vblank.h @@ -230,6 +230,7 @@ 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, -- 2.39.1 </blockquote></div>