[Intel-gfx] [PATCH 04/19] drm/i915: Add support for detecting vblanks when hw frame counter is unavailable.

[Maarten Lankhorst]

This uses the newly created drm_accurate_vblank_count_and_time to accurately
get a vblank count when the hw counter is unavailable.
---
 drivers/gpu/drm/i915/intel_display.c | 10 ++++++++++
 drivers/gpu/drm/i915/intel_drv.h     |  3 +++
 drivers/gpu/drm/i915/intel_sprite.c  |  8 ++------
 3 files changed, 15 insertions(+), 6 deletions(-)

diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
index ccbc2a448258..2086e8bd10da 100644
--- a/drivers/gpu/drm/i915/intel_display.c
+++ b/drivers/gpu/drm/i915/intel_display.c
@@ -13530,6 +13530,16 @@ static int intel_atomic_prepare_commit(struct drm_device *dev,
 	return ret;
 }
 
+u32 intel_crtc_get_vblank_counter(struct intel_crtc *crtc)
+{
+	struct drm_device *dev = crtc->base.dev;
+
+	if (!dev->max_vblank_count)
+		return drm_accurate_vblank_count(&crtc->base);
+
+	return dev->driver->get_vblank_counter(dev, crtc->pipe);
+}
+
 static void intel_atomic_wait_for_vblanks(struct drm_device *dev,
 					  struct drm_i915_private *dev_priv,
 					  unsigned crtc_mask)
diff --git a/drivers/gpu/drm/i915/intel_drv.h b/drivers/gpu/drm/i915/intel_drv.h
index fecc89600667..8efeb90eac07 100644
--- a/drivers/gpu/drm/i915/intel_drv.h
+++ b/drivers/gpu/drm/i915/intel_drv.h
@@ -1146,6 +1146,9 @@ intel_wait_for_vblank_if_active(struct drm_device *dev, int pipe)
 	if (crtc->active)
 		intel_wait_for_vblank(dev, pipe);
 }
+
+u32 intel_crtc_get_vblank_counter(struct intel_crtc *crtc);
+
 int ironlake_get_lanes_required(int target_clock, int link_bw, int bpp);
 void vlv_wait_port_ready(struct drm_i915_private *dev_priv,
 			 struct intel_digital_port *dport,
diff --git a/drivers/gpu/drm/i915/intel_sprite.c b/drivers/gpu/drm/i915/intel_sprite.c
index 0f3e2303e0e9..e2de6b0df5a8 100644
--- a/drivers/gpu/drm/i915/intel_sprite.c
+++ b/drivers/gpu/drm/i915/intel_sprite.c
@@ -80,9 +80,7 @@ static int usecs_to_scanlines(const struct drm_display_mode *adjusted_mode,
  */
 void intel_pipe_update_start(struct intel_crtc *crtc)
 {
-	struct drm_device *dev = crtc->base.dev;
 	const struct drm_display_mode *adjusted_mode = &crtc->config->base.adjusted_mode;
-	enum pipe pipe = crtc->pipe;
 	long timeout = msecs_to_jiffies_timeout(1);
 	int scanline, min, max, vblank_start;
 	wait_queue_head_t *wq = drm_crtc_vblank_waitqueue(&crtc->base);
@@ -139,8 +137,7 @@ void intel_pipe_update_start(struct intel_crtc *crtc)
 
 	crtc->debug.scanline_start = scanline;
 	crtc->debug.start_vbl_time = ktime_get();
-	crtc->debug.start_vbl_count =
-		dev->driver->get_vblank_counter(dev, pipe);
+	crtc->debug.start_vbl_count = intel_crtc_get_vblank_counter(crtc);
 
 	trace_i915_pipe_update_vblank_evaded(crtc);
 }
@@ -156,10 +153,9 @@ void intel_pipe_update_start(struct intel_crtc *crtc)
  */
 void intel_pipe_update_end(struct intel_crtc *crtc)
 {
-	struct drm_device *dev = crtc->base.dev;
 	enum pipe pipe = crtc->pipe;
 	int scanline_end = intel_get_crtc_scanline(crtc);
-	u32 end_vbl_count = dev->driver->get_vblank_counter(dev, pipe);
+	u32 end_vbl_count = intel_crtc_get_vblank_counter(crtc);
 	ktime_t end_vbl_time = ktime_get();
 
 	trace_i915_pipe_update_end(crtc, end_vbl_count, scanline_end);
-- 
2.1.0