diff options
Diffstat (limited to 'include/drm/drm_crtc.h')
| -rw-r--r-- | include/drm/drm_crtc.h | 46 |
1 files changed, 44 insertions, 2 deletions
diff --git a/include/drm/drm_crtc.h b/include/drm/drm_crtc.h index 6bef2f41d4d7..59b51a09cae6 100644 --- a/include/drm/drm_crtc.h +++ b/include/drm/drm_crtc.h @@ -887,6 +887,47 @@ 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); }; /** @@ -994,11 +1035,12 @@ struct drm_crtc { * Programmed mode in hw, after adjustments for encoders, crtc, panel * scaling etc. Should only be used by legacy drivers, for high * precision vblank timestamps in - * drm_calc_vbltimestamp_from_scanoutpos(). + * drm_crtc_vblank_helper_get_vblank_timestamp(). * * Note that atomic drivers should not use this, but instead use * &drm_crtc_state.adjusted_mode. And for high-precision timestamps - * drm_calc_vbltimestamp_from_scanoutpos() used &drm_vblank_crtc.hwmode, + * drm_crtc_vblank_helper_get_vblank_timestamp() used + * &drm_vblank_crtc.hwmode, * which is filled out by calling drm_calc_timestamping_constants(). */ struct drm_display_mode hwmode; |