drm/tilcdc: make frame_done interrupt active at all times

The frame_done interrupt was only being enabled when the vsync
interrupts were being enabled by DRM.  However the frame_done is
used to determine if the LCD controller has successfully completed
the raster_enable, raster_disable commands and the vsync interrupts
are not always enabled during these operations.
Signed-off-by: NDarren Etheridge <detheridge@ti.com>
Tested-by: NDave Gerlach <d-gerlach@ti.com>
Signed-off-by: NJyri Sarha <jsarha@ti.com>
Reviewed-by: NTomi Valkeinen <tomi.valkeinen@ti.com>

drivers/gpu/drm/tilcdc/tilcdc_drv.c

@@ -369,7 +369,9 @@ static int tilcdc_irq_postinstall(struct drm_device *dev)
 	if (priv->rev == 1)
 		tilcdc_set(dev, LCDC_RASTER_CTRL_REG, LCDC_V1_UNDERFLOW_INT_ENA);
 	else
-		tilcdc_set(dev, LCDC_INT_ENABLE_SET_REG, LCDC_V2_UNDERFLOW_INT_ENA);
+		tilcdc_set(dev, LCDC_INT_ENABLE_SET_REG,
+			   LCDC_V2_UNDERFLOW_INT_ENA |
+			   LCDC_FRAME_DONE);
 
 	return 0;
 }
@@ -403,7 +405,7 @@ static void enable_vblank(struct drm_device *dev, bool enable)
 	} else {
 		reg = LCDC_INT_ENABLE_SET_REG;
 		mask = LCDC_V2_END_OF_FRAME0_INT_ENA |
-			LCDC_V2_END_OF_FRAME1_INT_ENA | LCDC_FRAME_DONE;
+			LCDC_V2_END_OF_FRAME1_INT_ENA;
 	}
 
 	if (enable)