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| author | Imre Deak <imre.deak@intel.com> | 2012-10-23 22:53:25 +0400 |
|---|---|---|
| committer | Dave Airlie <airlied@redhat.com> | 2012-11-20 10:06:15 +0400 |
| commit | e62f2f5acba1d466da047983ae16f6b96b68b310 (patch) | |
| tree | 08ff1fd73c55c3b781047415e816aeb3a3b45de4 | |
| parent | 11e686855c81c2e5e647b3dcfabd2a4e473c46f0 (diff) | |
| download | linux-e62f2f5acba1d466da047983ae16f6b96b68b310.tar.xz | |
drm: use monotonic time in drm_calc_vbltimestamp_from_scanoutpos
For measuring duration we want to avoid that our start/end timestamps
jump, so use monotonic instead of real time for that.
Signed-off-by: Imre Deak <imre.deak@intel.com>
Reviewed-by: mario.kleiner
Signed-off-by: Dave Airlie <airlied@redhat.com>
| -rw-r--r-- | drivers/gpu/drm/drm_irq.c | 18 |
1 files changed, 12 insertions, 6 deletions
diff --git a/drivers/gpu/drm/drm_irq.c b/drivers/gpu/drm/drm_irq.c index 44602ef55afc..ef5b5f70735e 100644 --- a/drivers/gpu/drm/drm_irq.c +++ b/drivers/gpu/drm/drm_irq.c @@ -576,7 +576,8 @@ int drm_calc_vbltimestamp_from_scanoutpos(struct drm_device *dev, int crtc, unsigned flags, struct drm_crtc *refcrtc) { - struct timeval stime, raw_time; + ktime_t stime, etime, mono_time_offset; + struct timeval tv_etime; struct drm_display_mode *mode; int vbl_status, vtotal, vdisplay; int vpos, hpos, i; @@ -625,13 +626,14 @@ int drm_calc_vbltimestamp_from_scanoutpos(struct drm_device *dev, int crtc, preempt_disable(); /* Get system timestamp before query. */ - do_gettimeofday(&stime); + stime = ktime_get(); /* Get vertical and horizontal scanout pos. vpos, hpos. */ vbl_status = dev->driver->get_scanout_position(dev, crtc, &vpos, &hpos); /* Get system timestamp after query. */ - do_gettimeofday(&raw_time); + etime = ktime_get(); + mono_time_offset = ktime_get_monotonic_offset(); preempt_enable(); @@ -642,7 +644,7 @@ int drm_calc_vbltimestamp_from_scanoutpos(struct drm_device *dev, int crtc, return -EIO; } - duration_ns = timeval_to_ns(&raw_time) - timeval_to_ns(&stime); + duration_ns = ktime_to_ns(etime) - ktime_to_ns(stime); /* Accept result with < max_error nsecs timing uncertainty. */ if (duration_ns <= (s64) *max_error) @@ -689,14 +691,18 @@ int drm_calc_vbltimestamp_from_scanoutpos(struct drm_device *dev, int crtc, vbl_status |= 0x8; } + etime = ktime_sub(etime, mono_time_offset); + /* save this only for debugging purposes */ + tv_etime = ktime_to_timeval(etime); /* Subtract time delta from raw timestamp to get final * vblank_time timestamp for end of vblank. */ - *vblank_time = ns_to_timeval(timeval_to_ns(&raw_time) - delta_ns); + etime = ktime_sub_ns(etime, delta_ns); + *vblank_time = ktime_to_timeval(etime); DRM_DEBUG("crtc %d : v %d p(%d,%d)@ %ld.%ld -> %ld.%ld [e %d us, %d rep]\n", crtc, (int)vbl_status, hpos, vpos, - (long)raw_time.tv_sec, (long)raw_time.tv_usec, + (long)tv_etime.tv_sec, (long)tv_etime.tv_usec, (long)vblank_time->tv_sec, (long)vblank_time->tv_usec, (int)duration_ns/1000, i); |