drm: Use ktime_mono_to_real()

Convert the monotonic timestamp with ktime_mono_to_real() in
drm_calc_vbltimestamp_from_scanoutpos().

In get_drm_timestamp we can call either ktime_get() or
ktime_get_real() depending on drm_timestamp_monotonic. No point in
having two calls into the core for CLOCK_REALTIME.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: John Stultz <john.stultz@linaro.org>

diff --git a/drivers/gpu/drm/drm_irq.c b/drivers/gpu/drm/drm_irq.c
index 0de123a..08ba120 100644 (file)
--- a/drivers/gpu/drm/drm_irq.c
+++ b/drivers/gpu/drm/drm_irq.c
@@ -542,8 +542,8 @@ int drm_calc_vbltimestamp_from_scanoutpos(struct drm_device *dev, int crtc,
                                          const struct drm_crtc *refcrtc,
                                          const struct drm_display_mode *mode)
 {
-       ktime_t stime, etime, mono_time_offset;
        struct timeval tv_etime;
+       ktime_t stime, etime;
        int vbl_status;
        int vpos, hpos, i;
        int framedur_ns, linedur_ns, pixeldur_ns, delta_ns, duration_ns;
@@ -588,13 +588,6 @@ int drm_calc_vbltimestamp_from_scanoutpos(struct drm_device *dev, int crtc,
                vbl_status = dev->driver->get_scanout_position(dev, crtc, flags, &vpos,
                                                               &hpos, &stime, &etime);
 
-               /*
-                * Get correction for CLOCK_MONOTONIC -> CLOCK_REALTIME if
-                * CLOCK_REALTIME is requested.
-                */
-               if (!drm_timestamp_monotonic)
-                       mono_time_offset = ktime_get_monotonic_offset();
-
                /* Return as no-op if scanout query unsupported or failed. */
                if (!(vbl_status & DRM_SCANOUTPOS_VALID)) {
                        DRM_DEBUG("crtc %d : scanoutpos query failed [%d].\n",
@@ -633,7 +626,7 @@ int drm_calc_vbltimestamp_from_scanoutpos(struct drm_device *dev, int crtc,
        delta_ns = vpos * linedur_ns + hpos * pixeldur_ns;
 
        if (!drm_timestamp_monotonic)
-               etime = ktime_sub(etime, mono_time_offset);
+               etime = ktime_mono_to_real(etime);
 
        /* save this only for debugging purposes */
        tv_etime = ktime_to_timeval(etime);
@@ -664,10 +657,7 @@ static struct timeval get_drm_timestamp(void)
 {
        ktime_t now;
 
-       now = ktime_get();
-       if (!drm_timestamp_monotonic)
-               now = ktime_sub(now, ktime_get_monotonic_offset());
-
+       now = drm_timestamp_monotonic ? ktime_get() : ktime_get_real();
        return ktime_to_timeval(now);
 }