On Mon, Apr 3, 2017 at 4:14 PM, Maxime Ripard
[off-list ref] wrote:

Hi,

On Thu, Mar 30, 2017 at 03:46:06AM +0800, Icenowy Zheng wrote:

quoted

As we are going to add support for the Allwinner DE2 Mixer in sun4i-drm
driver, we will finally have two types of layer.

Abstract the layer type to void * and a ops struct, which contains the
only function used by crtc -- get the drm_plane struct of the layer.

Signed-off-by: Icenowy Zheng <icenowy@aosc.io>
---
Refactored patch in v3.

 drivers/gpu/drm/sun4i/sun4i_crtc.c  | 19 +++++++++++--------
 drivers/gpu/drm/sun4i/sun4i_crtc.h  |  3 ++-
 drivers/gpu/drm/sun4i/sun4i_layer.c | 19 ++++++++++++++++++-
 drivers/gpu/drm/sun4i/sun4i_layer.h |  2 +-
 drivers/gpu/drm/sun4i/sunxi_layer.h | 17 +++++++++++++++++
 5 files changed, 49 insertions(+), 11 deletions(-)
 create mode 100644 drivers/gpu/drm/sun4i/sunxi_layer.h

diff --git a/drivers/gpu/drm/sun4i/sun4i_crtc.c b/drivers/gpu/drm/sun4i/sun4i_crtc.c
index 3c876c3a356a..33854ee7f636 100644
--- a/drivers/gpu/drm/sun4i/sun4i_crtc.c
+++ b/drivers/gpu/drm/sun4i/sun4i_crtc.c

@@ -29,6 +29,7 @@
 #include "sun4i_crtc.h"
 #include "sun4i_drv.h"
 #include "sun4i_layer.h"
+#include "sunxi_layer.h"
 #include "sun4i_tcon.h"

 static void sun4i_crtc_atomic_begin(struct drm_crtc *crtc,

@@ -149,7 +150,7 @@ struct sun4i_crtc *sun4i_crtc_init(struct drm_device *drm,
      scrtc->tcon = tcon;

      /* Create our layers */
-     scrtc->layers = sun4i_layers_init(drm, scrtc->backend);
+     scrtc->layers = (void **)sun4i_layers_init(drm, scrtc);
      if (IS_ERR(scrtc->layers)) {
              dev_err(drm->dev, "Couldn't create the planes\n");
              return NULL;

@@ -157,14 +158,15 @@ struct sun4i_crtc *sun4i_crtc_init(struct drm_device *drm,

      /* find primary and cursor planes for drm_crtc_init_with_planes */
      for (i = 0; scrtc->layers[i]; i++) {
-             struct sun4i_layer *layer = scrtc->layers[i];
+             void *layer = scrtc->layers[i];
+             struct drm_plane *plane = scrtc->layer_ops->get_plane(layer);

-             switch (layer->plane.type) {
+             switch (plane->type) {
              case DRM_PLANE_TYPE_PRIMARY:
-                     primary = &layer->plane;
+                     primary = plane;
                      break;
              case DRM_PLANE_TYPE_CURSOR:
-                     cursor = &layer->plane;
+                     cursor = plane;
                      break;
              default:
                      break;

@@ -190,10 +192,11 @@ struct sun4i_crtc *sun4i_crtc_init(struct drm_device *drm,
      /* Set possible_crtcs to this crtc for overlay planes */
      for (i = 0; scrtc->layers[i]; i++) {
              uint32_t possible_crtcs = BIT(drm_crtc_index(&scrtc->crtc));
-             struct sun4i_layer *layer = scrtc->layers[i];
+             void *layer = scrtc->layers[i];
+             struct drm_plane *plane = scrtc->layer_ops->get_plane(layer);

-             if (layer->plane.type == DRM_PLANE_TYPE_OVERLAY)
-                     layer->plane.possible_crtcs = possible_crtcs;
+             if (plane->type == DRM_PLANE_TYPE_OVERLAY)
+                     plane->possible_crtcs = possible_crtcs;

I think the logic should be reversed here, the CRTC shouldn't care
(much) about the layers at all.

Correct. It shouldn't. However since the layers are tied to a specific
crtc, they get created as part of the crtc init sequence.

We should modify sun4i_crtc_init to get the argument it needs (primary
and cursor planes for example) through its parameters, and have the
caller (which iirc is sun4i_drv) call it with the right parameters

The caller is (now) sun4i_crtc_init.

depending on whether you're using DE or DE2.

Ack.

If we're doing that, I don't think we even need the pointer to the
array of layers in struct sun4i_crtc, which will make it easier to
deal with.

Ack.

ChenYu