drm/imx: use PRG/PRE when possible
Allow the planes to use the PRG/PRE units as linear prefetchers when
possible. This improves DRAM efficiency a bit and reduces the chance
for display underflow when the memory subsystem is under load.
This does not yet support scanning out tiled buffers directly, as this
needs more work, but it already wires up the basic interaction between
imx-drm, the IPUv3 driver and the PRG and PRE drivers.
Signed-off-by: Lucas Stach <l.stach@pengutronix.de>
Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
diff --git a/drivers/gpu/drm/imx/imx-drm.h b/drivers/gpu/drm/imx/imx-drm.h
index cc00333..295434b 100644
--- a/drivers/gpu/drm/imx/imx-drm.h
+++ b/drivers/gpu/drm/imx/imx-drm.h
@@ -39,4 +39,7 @@ int imx_drm_encoder_parse_of(struct drm_device *drm,
void imx_drm_connector_destroy(struct drm_connector *connector);
void imx_drm_encoder_destroy(struct drm_encoder *encoder);
+int ipu_planes_assign_pre(struct drm_device *dev,
+ struct drm_atomic_state *state);
+
#endif /* _IMX_DRM_H_ */