[PATCH 2/7] Revert "drm/vblank: Restoring vblank counts after device PM events."

[StanLis]

From: Stanislav Lisovskiy <stanislav.lisovskiy at intel.com>

This reverts commit d0bb96b4be69feea97f16de5306c35e280658931.
---
 drivers/gpu/drm/drm_vblank.c | 65 ------------------------------------
 include/drm/drm_vblank.h     |  2 --
 2 files changed, 67 deletions(-)

diff --git a/drivers/gpu/drm/drm_vblank.c b/drivers/gpu/drm/drm_vblank.c
index 28cdcf76b6f9..e9b1bafaae56 100644
--- a/drivers/gpu/drm/drm_vblank.c
+++ b/drivers/gpu/drm/drm_vblank.c
@@ -1246,71 +1246,6 @@ void drm_crtc_vblank_on(struct drm_crtc *crtc)
 }
 EXPORT_SYMBOL(drm_crtc_vblank_on);
 
-/**
- * drm_vblank_restore - estimate missed vblanks and update vblank count.
- * @dev: DRM device
- * @pipe: CRTC index
- *
- * Power manamement features can cause frame counter resets between vblank
- * disable and enable. Drivers can use this function in their
- * &drm_crtc_funcs.enable_vblank implementation to estimate missed vblanks since
- * the last &drm_crtc_funcs.disable_vblank using timestamps and update the
- * vblank counter.
- *
- * This function is the legacy version of drm_crtc_vblank_restore().
- */
-void drm_vblank_restore(struct drm_device *dev, unsigned int pipe)
-{
-	ktime_t t_vblank;
-	struct drm_vblank_crtc *vblank;
-	int framedur_ns;
-	u64 diff_ns;
-	u32 cur_vblank, diff = 1;
-	int count = DRM_TIMESTAMP_MAXRETRIES;
-
-	if (WARN_ON(pipe >= dev->num_crtcs))
-		return;
-
-	assert_spin_locked(&dev->vbl_lock);
-	assert_spin_locked(&dev->vblank_time_lock);
-
-	vblank = &dev->vblank[pipe];
-	WARN_ONCE((drm_debug & DRM_UT_VBL) && !vblank->framedur_ns,
-		  "Cannot compute missed vblanks without frame duration\n");
-	framedur_ns = vblank->framedur_ns;
-
-	do {
-		cur_vblank = __get_vblank_counter(dev, pipe);
-		drm_get_last_vbltimestamp(dev, pipe, &t_vblank, false);
-	} while (cur_vblank != __get_vblank_counter(dev, pipe) && --count > 0);
-
-	diff_ns = ktime_to_ns(ktime_sub(t_vblank, vblank->time));
-	if (framedur_ns)
-		diff = DIV_ROUND_CLOSEST_ULL(diff_ns, framedur_ns);
-
-
-	DRM_DEBUG_VBL("missed %d vblanks in %lld ns, frame duration=%d ns, hw_diff=%d\n",
-		      diff, diff_ns, framedur_ns, cur_vblank - vblank->last);
-	store_vblank(dev, pipe, diff, t_vblank, cur_vblank);
-}
-EXPORT_SYMBOL(drm_vblank_restore);
-
-/**
- * drm_crtc_vblank_restore - estimate missed vblanks and update vblank count.
- * @crtc: CRTC in question
- *
- * Power manamement features can cause frame counter resets between vblank
- * disable and enable. Drivers can use this function in their
- * &drm_crtc_funcs.enable_vblank implementation to estimate missed vblanks since
- * the last &drm_crtc_funcs.disable_vblank using timestamps and update the
- * vblank counter.
- */
-void drm_crtc_vblank_restore(struct drm_crtc *crtc)
-{
-	drm_vblank_restore(crtc->dev, drm_crtc_index(crtc));
-}
-EXPORT_SYMBOL(drm_crtc_vblank_restore);
-
 static void drm_legacy_vblank_pre_modeset(struct drm_device *dev,
 					  unsigned int pipe)
 {
diff --git a/include/drm/drm_vblank.h b/include/drm/drm_vblank.h
index d25a9603ab57..ee1f65899eac 100644
--- a/include/drm/drm_vblank.h
+++ b/include/drm/drm_vblank.h
@@ -196,8 +196,6 @@ void drm_crtc_vblank_off(struct drm_crtc *crtc);
 void drm_crtc_vblank_reset(struct drm_crtc *crtc);
 void drm_crtc_vblank_on(struct drm_crtc *crtc);
 u64 drm_crtc_accurate_vblank_count(struct drm_crtc *crtc);
-void drm_vblank_restore(struct drm_device *dev, unsigned int pipe);
-void drm_crtc_vblank_restore(struct drm_crtc *crtc);
 
 bool drm_calc_vbltimestamp_from_scanoutpos(struct drm_device *dev,
 					   unsigned int pipe, int *max_error,
-- 
2.17.0