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authorThomas Zimmermann <tzimmermann@suse.de>2020-01-23 16:59:24 +0300
committerThomas Zimmermann <tzimmermann@suse.de>2020-02-13 15:08:13 +0300
commit7fe3f0d15aac6c98a97e6d7086f5a6b7bc4ccae4 (patch)
treeff005fcab13165c3859c8c4cdce19b181f666e26 /drivers/gpu/drm/drm_vblank.c
parentf1e2b6371c12aec5e772e5fdedaa4455c20a787f (diff)
downloadlinux-7fe3f0d15aac6c98a97e6d7086f5a6b7bc4ccae4.tar.xz
drm: Add get_vblank_timestamp() to struct drm_crtc_funcs
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_vblank_helper_get_vblank_timestamp(), which is an implementation for the CRTC callback. v4: * more readable code for setting high_prec (Ville, Jani) v3: * use refactored timestamp calculation to minimize duplicated code * do more checks for crtc != NULL to support legacy drivers v2: * rename helper to drm_crtc_vblank_helper_get_vblank_timestamp() * replace drm_calc_vbltimestamp_from_scanoutpos() with drm_crtc_vblank_helper_get_vblank_timestamp() in docs Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de> Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com> Link: https://patchwork.freedesktop.org/patch/msgid/20200123135943.24140-4-tzimmermann@suse.de
Diffstat (limited to 'drivers/gpu/drm/drm_vblank.c')
-rw-r--r--drivers/gpu/drm/drm_vblank.c76
1 files changed, 67 insertions, 9 deletions
diff --git a/drivers/gpu/drm/drm_vblank.c b/drivers/gpu/drm/drm_vblank.c
index 496395324d1f..cc7ef64d35f2 100644
--- a/drivers/gpu/drm/drm_vblank.c
+++ b/drivers/gpu/drm/drm_vblank.c
@@ -339,7 +339,9 @@ 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);
@@ -539,9 +541,9 @@ EXPORT_SYMBOL(drm_crtc_vblank_waitqueue);
*
* Calculate and store various constants which are later needed by vblank and
* swap-completion timestamping, e.g, by
- * drm_calc_vbltimestamp_from_scanoutpos(). They are derived from CRTC's true
- * scanout timing, so they take things like panel scaling or other adjustments
- * into account.
+ * drm_crtc_vblank_helper_get_vblank_timestamp(). They are derived from
+ * CRTC's true scanout timing, so they take things like panel scaling or
+ * other adjustments into account.
*/
void drm_calc_timestamping_constants(struct drm_crtc *crtc,
const struct drm_display_mode *mode)
@@ -605,8 +607,9 @@ 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 or
+ * &drm_driver.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
@@ -803,6 +806,48 @@ drm_crtc_vblank_helper_get_vblank_timestamp_internal(
EXPORT_SYMBOL(drm_crtc_vblank_helper_get_vblank_timestamp_internal);
/**
+ * drm_crtc_vblank_helper_get_vblank_timestamp - 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_vblank_helper_get_vblank_timestamp(struct drm_crtc *crtc,
+ int *max_error,
+ ktime_t *vblank_time,
+ bool in_vblank_irq)
+{
+ return drm_crtc_vblank_helper_get_vblank_timestamp_internal(
+ crtc, max_error, vblank_time, in_vblank_irq,
+ crtc->helper_private->get_scanout_position, NULL);
+}
+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
@@ -827,15 +872,22 @@ 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 && 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.
@@ -1818,6 +1870,8 @@ done:
static void drm_handle_vblank_events(struct drm_device *dev, unsigned int pipe)
{
+ struct drm_crtc *crtc = drm_crtc_from_index(dev, pipe);
+ bool high_prec = false;
struct drm_pending_vblank_event *e, *t;
ktime_t now;
u64 seq;
@@ -1840,8 +1894,12 @@ 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);
+ if (crtc && crtc->funcs->get_vblank_timestamp)
+ high_prec = true;
+ else if (dev->driver->get_vblank_timestamp)
+ high_prec = true;
+
+ trace_drm_vblank_event(pipe, seq, now, high_prec);
}
/**