Retrieve raw timestamp for the most recent vblank interval
u32 drm_get_last_vbltimestamp(struct drm_device * dev, int crtc, struct timeval * tvblank, unsigned flags);
dev
DRM device
crtc
which CRTC's vblank timestamp to retrieve
tvblank
Pointer to target struct timeval which should receive the timestamp
flags
Flags to pass to driver: 0 = Default, DRM_CALLED_FROM_VBLIRQ = If function is called from vbl IRQ handler
Fetches the system timestamp corresponding to the time of the most recent vblank interval on specified CRTC. May call into kms-driver to compute the timestamp with a high-precision GPU specific method.
Returns zero if timestamp originates from uncorrected do_gettimeofday call, i.e., it isn't very precisely locked to the true vblank.
Non-zero if timestamp is considered to be very precise, zero otherwise.
Jesse Barnes <[email protected]>
Intel Corporation,
Initial version
Laurent Pinchart <[email protected]>
Ideas on board SPRL,
Driver internals
Daniel Vetter <[email protected]>
Intel Corporation,
Contributions all over the place