The callback get_vblank_timestamp() is currently located in struct
drm_driver, but really belongs into struct drm_crtc_funcs. Add an
equivalent there. Driver will be converted in separate patches.
The default implementation is drm_calc_vbltimestamp_from_scanoutpos().
The patch adds drm_crtc_calc_vbltimestamp_from_scanoutpos(), which is
an implementation for the CRTC callback.
Signed-off-by: Thomas Zimmermann <tzimmermann@xxxxxxx>
---
drivers/gpu/drm/drm_vblank.c | 83 +++++++++++++++++++++---
include/drm/drm_crtc.h | 41 ++++++++++++
include/drm/drm_modeset_helper_vtables.h | 2 +-
include/drm/drm_vblank.h | 4 ++
4 files changed, 120 insertions(+), 10 deletions(-)
diff --git a/drivers/gpu/drm/drm_vblank.c b/drivers/gpu/drm/drm_vblank.c
index cbe8f3009df5..7cf436a4b908 100644
--- a/drivers/gpu/drm/drm_vblank.c
+++ b/drivers/gpu/drm/drm_vblank.c
@@ -333,7 +333,9 @@ u64 drm_crtc_accurate_vblank_count(struct drm_crtc *crtc)
u64 vblank;
unsigned long flags;
- WARN_ONCE(drm_debug_enabled(DRM_UT_VBL) && !dev->driver->get_vblank_timestamp,
+ WARN_ONCE(drm_debug_enabled(DRM_UT_VBL) &&
+ !crtc->funcs->get_vblank_timestamp &&
+ !dev->driver->get_vblank_timestamp,
"This function requires support for accurate vblank timestamps.");
spin_lock_irqsave(&dev->vblank_time_lock, flags);
@@ -563,6 +565,50 @@ void drm_calc_timestamping_constants(struct drm_crtc *crtc,
}
EXPORT_SYMBOL(drm_calc_timestamping_constants);
+/**
+ * drm_crtc_calc_vbltimestamp_from_scanoutpos - precise vblank timestamp helper
+ * @crtc: CRTC whose vblank timestamp to retrieve
+ * @max_error: Desired maximum allowable error in timestamps (nanosecs)
+ * On return contains true maximum error of timestamp
+ * @vblank_time: Pointer to time which should receive the timestamp
+ * @in_vblank_irq:
+ * True when called from drm_crtc_handle_vblank(). Some drivers
+ * need to apply some workarounds for gpu-specific vblank irq quirks
+ * if flag is set.
+ *
+ * Implements calculation of exact vblank timestamps from given drm_display_mode
+ * timings and current video scanout position of a CRTC. This can be directly
+ * used as the &drm_crtc_funcs.get_vblank_timestamp implementation of a kms
+ * driver if &drm_crtc_helper_funcs.get_scanout_position is implemented.
+ *
+ * The current implementation only handles standard video modes. For double scan
+ * and interlaced modes the driver is supposed to adjust the hardware mode
+ * (taken from &drm_crtc_state.adjusted mode for atomic modeset drivers) to
+ * match the scanout position reported.
+ *
+ * Note that atomic drivers must call drm_calc_timestamping_constants() before
+ * enabling a CRTC. The atomic helpers already take care of that in
+ * drm_atomic_helper_update_legacy_modeset_state().
+ *
+ * Returns:
+ *
+ * Returns true on success, and false on failure, i.e. when no accurate
+ * timestamp could be acquired.
+ */
+bool drm_crtc_calc_vbltimestamp_from_scanoutpos(struct drm_crtc *crtc,
+ int *max_error,
+ ktime_t *vblank_time,
+ bool in_vblank_irq)
+{
+ struct drm_device *dev = crtc->dev;
+ unsigned int pipe = crtc->index;
+
+ return drm_calc_vbltimestamp_from_scanoutpos(dev, pipe, max_error,
+ vblank_time,
+ in_vblank_irq);
+}
+EXPORT_SYMBOL(drm_crtc_calc_vbltimestamp_from_scanoutpos);
+
/**
* drm_calc_vbltimestamp_from_scanoutpos - precise vblank timestamp helper
* @dev: DRM device
@@ -577,8 +623,8 @@ EXPORT_SYMBOL(drm_calc_timestamping_constants);
*
* Implements calculation of exact vblank timestamps from given drm_display_mode
* timings and current video scanout position of a CRTC. This can be directly
- * used as the &drm_driver.get_vblank_timestamp implementation of a kms driver
- * if &drm_crtc_helper_funcs.get_scanout_position is implemented.
+ * used as the &drm_crtc_funcs.get_vblank_timestamp implementation of a kms
+ * driver if &drm_crtc_helper_funcs.get_scanout_position is implemented.
*
* The current implementation only handles standard video modes. For double scan
* and interlaced modes the driver is supposed to adjust the hardware mode
@@ -733,15 +779,22 @@ 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);
bool ret = false;
/* Define requested maximum error on timestamps (nanoseconds). */
int max_error = (int) drm_timestamp_precision * 1000;
/* Query driver if possible and precision timestamping enabled. */
- if (dev->driver->get_vblank_timestamp && (max_error > 0))
+ if (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);
+ } else if (dev->driver->get_vblank_timestamp && (max_error > 0)) {
ret = dev->driver->get_vblank_timestamp(dev, pipe, &max_error,
tvblank, in_vblank_irq);
+ }
/* GPU high precision timestamp query unsupported or failed.
* Return current monotonic/gettimeofday timestamp as best estimate.
@@ -1050,11 +1103,19 @@ EXPORT_SYMBOL(drm_crtc_vblank_get);
static bool __vblank_disable_immediate(struct drm_device *dev, unsigned int pipe)
{
+ struct drm_crtc *crtc;
+
if (!dev->vblank_disable_immediate)
return false;
- if (!dev->driver->get_vblank_timestamp)
- return false;
- return true;
+
+ crtc = drm_crtc_from_index(dev, pipe);
+ if (crtc && crtc->funcs->get_vblank_timestamp)
+ return true;
+
+ if (dev->driver->get_vblank_timestamp)
+ return true;
+
+ return false;
}
static void drm_vblank_put(struct drm_device *dev, unsigned int pipe)
@@ -1733,9 +1794,11 @@ int drm_wait_vblank_ioctl(struct drm_device *dev, void *data,
static void drm_handle_vblank_events(struct drm_device *dev, unsigned int pipe)
{
+ struct drm_crtc *crtc = drm_crtc_from_index(dev, pipe);
struct drm_pending_vblank_event *e, *t;
ktime_t now;
u64 seq;
+ bool high_prec;
assert_spin_locked(&dev->event_lock);
@@ -1755,8 +1818,10 @@ 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, now,
- dev->driver->get_vblank_timestamp != NULL);
+ high_prec = crtc->funcs->get_vblank_timestamp ||
+ dev->driver->get_vblank_timestamp;
+
+ trace_drm_vblank_event(pipe, seq, now, high_prec);
}
/**
diff --git a/include/drm/drm_crtc.h b/include/drm/drm_crtc.h
index 5e9b15a0e8c5..2caad975f415 100644
--- a/include/drm/drm_crtc.h
+++ b/include/drm/drm_crtc.h
@@ -867,6 +867,47 @@ struct drm_crtc_funcs {
* new drivers as the replacement of &drm_driver.disable_vblank hook.
*/
void (*disable_vblank)(struct drm_crtc *crtc);
+
+ /**
+ * @get_vblank_timestamp:
+ *
+ * Called by drm_get_last_vbltimestamp(). Should return a precise
+ * timestamp when the most recent vblank interval ended or will end.
+ *
+ * Specifically, the timestamp in @vblank_time should correspond as
+ * closely as possible to the time when the first video scanline of
+ * the video frame after the end of vblank will start scanning out,
+ * the time immediately after end of the vblank interval. If the
+ * @crtc is currently inside vblank, this will be a time in the future.
+ * If the @crtc is currently scanning out a frame, this will be the
+ * past start time of the current scanout. This is meant to adhere
+ * to the OpenML OML_sync_control extension specification.
+ *
+ * Parameters:
+ *
+ * crtc:
+ * CRTC for which timestamp should be returned.
+ * max_error:
+ * Maximum allowable timestamp error in nanoseconds.
+ * Implementation should strive to provide timestamp
+ * with an error of at most max_error nanoseconds.
+ * Returns true upper bound on error for timestamp.
+ * vblank_time:
+ * Target location for returned vblank timestamp.
+ * in_vblank_irq:
+ * True when called from drm_crtc_handle_vblank(). Some drivers
+ * need to apply some workarounds for gpu-specific vblank irq quirks
+ * if flag is set.
+ *
+ * Returns:
+ *
+ * True on success, false on failure, which means the core should
+ * fallback to a simple timestamp taken in drm_crtc_handle_vblank().
+ */
+ bool (*get_vblank_timestamp)(struct drm_crtc *crtc,
+ int *max_error,
+ ktime_t *vblank_time,
+ bool in_vblank_irq);
};
/**
diff --git a/include/drm/drm_modeset_helper_vtables.h b/include/drm/drm_modeset_helper_vtables.h
index e398512bfd5f..d735f7088a10 100644
--- a/include/drm/drm_modeset_helper_vtables.h
+++ b/include/drm/drm_modeset_helper_vtables.h
@@ -460,7 +460,7 @@ struct drm_crtc_helper_funcs {
* optional accurate ktime_get() timestamp of when the position was
* measured. Note that this is a helper callback which is only used
* if a driver uses drm_calc_vbltimestamp_from_scanoutpos() for the
- * @drm_driver.get_vblank_timestamp callback.
+ * @drm_crtc_funcs.get_vblank_timestamp callback.
*
* Parameters:
*
diff --git a/include/drm/drm_vblank.h b/include/drm/drm_vblank.h
index c16c44052b3d..cdc567c83805 100644
--- a/include/drm/drm_vblank.h
+++ b/include/drm/drm_vblank.h
@@ -233,6 +233,10 @@ bool drm_calc_vbltimestamp_from_scanoutpos(struct drm_device *dev,
unsigned int pipe, int *max_error,
ktime_t *vblank_time,
bool in_vblank_irq);
+bool drm_crtc_calc_vbltimestamp_from_scanoutpos(struct drm_crtc *crtc,
+ int *max_error,
+ ktime_t *vblank_time,
+ bool in_vblank_irq);
void drm_calc_timestamping_constants(struct drm_crtc *crtc,
const struct drm_display_mode *mode);
wait_queue_head_t *drm_crtc_vblank_waitqueue(struct drm_crtc *crtc);
--
2.24.1
