drm/tilcdc: Add prints on sync lost and FIFO underrun interrupts

Add ratelimited prints on sync lost and FIFO underrun interrupts.

Signed-off-by: Jyri Sarha <jsarha@ti.com>
Reviewed-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
diff --git a/drivers/gpu/drm/tilcdc/tilcdc_crtc.c b/drivers/gpu/drm/tilcdc/tilcdc_crtc.c
index b1df046..5ee22c6 100644
--- a/drivers/gpu/drm/tilcdc/tilcdc_crtc.c
+++ b/drivers/gpu/drm/tilcdc/tilcdc_crtc.c
@@ -717,6 +717,14 @@
 		tilcdc_write(dev, LCDC_END_OF_INT_IND_REG, 0);
 	}
 
+	if (stat & LCDC_SYNC_LOST)
+		dev_err_ratelimited(dev->dev, "%s(0x%08x): Sync lost",
+				    __func__, stat);
+
+	if (stat & LCDC_FIFO_UNDERFLOW)
+		dev_err_ratelimited(dev->dev, "%s(0x%08x): FIFO underfow",
+				    __func__, stat);
+
 	return IRQ_HANDLED;
 }