diff mbox series

[v7,10/15] drm/vblank: Add helper to get next vblank time

Message ID 20230227193535.2822389-11-robdclark@gmail.com (mailing list archive)
State New, archived
Headers show
Series dma-fence: Deadline awareness | expand

Commit Message

Rob Clark Feb. 27, 2023, 7:35 p.m. UTC 
From: Rob Clark <robdclark@chromium.org>

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 <robdclark@chromium.org>
---
 drivers/gpu/drm/drm_vblank.c | 53 ++++++++++++++++++++++++++++++------
 include/drm/drm_vblank.h     |  1 +
 2 files changed, 45 insertions(+), 9 deletions(-)

Comments

Mario Kleiner Feb. 28, 2023, 10:08 p.m. UTC | #1 
LGTM. This one is

Reviewed-by: Mario Kleiner <mario.kleiner.de@gmail.com>

-mario


On Mon, Feb 27, 2023 at 8:36 PM Rob Clark <robdclark@gmail.com> wrote:

> From: Rob Clark <robdclark@chromium.org>
>
> 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 <robdclark@chromium.org>
> ---
>  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
>
>
diff mbox series

Patch

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,