drm/i915: Add flip done tracepoint

Add a tracepoint to see exactly when async flips complete.
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240611133344.30673-4-ville.syrjala@linux.intel.comReviewed-by: Jani Nikula <jani.nikula@intel.com>

drivers/gpu/drm/i915/display/intel_display_irq.c

@@ -346,6 +346,7 @@ static void flip_done_handler(struct drm_i915_private *i915,
 	spin_lock(&i915->drm.event_lock);
 
 	if (crtc->flip_done_event) {
+		trace_intel_crtc_flip_done(crtc);
 		drm_crtc_send_vblank_event(&crtc->base, crtc->flip_done_event);
 		crtc->flip_done_event = NULL;
 	}

drivers/gpu/drm/i915/display/intel_display_trace.h

@@ -78,6 +78,29 @@ TRACE_EVENT(intel_pipe_disable,
 		      __entry->frame[PIPE_C], __entry->scanline[PIPE_C])
 );
 
+TRACE_EVENT(intel_crtc_flip_done,
+	    TP_PROTO(struct intel_crtc *crtc),
+	    TP_ARGS(crtc),
+
+	    TP_STRUCT__entry(
+			     __string(dev, __dev_name_kms(crtc))
+			     __field(enum pipe, pipe)
+			     __field(u32, frame)
+			     __field(u32, scanline)
+			     ),
+
+	    TP_fast_assign(
+			   __assign_str(dev);
+			   __entry->pipe = crtc->pipe;
+			   __entry->frame = intel_crtc_get_vblank_counter(crtc);
+			   __entry->scanline = intel_get_crtc_scanline(crtc);
+			   ),
+
+	    TP_printk("dev %s, pipe %c, frame=%u, scanline=%u",
+		      __get_str(dev), pipe_name(__entry->pipe),
+		      __entry->frame, __entry->scanline)
+);
+
 TRACE_EVENT(intel_pipe_crc,
 	    TP_PROTO(struct intel_crtc *crtc, const u32 *crcs),
 	    TP_ARGS(crtc, crcs),