Il 17/05/24 11:49, Michael Walle ha scritto:
Hi Angelo,

On Thu May 16, 2024 at 10:11 AM CEST, AngeloGioacchino Del Regno wrote:
Implement OF graphs support to the mediatek-drm drivers, allowing to
stop hardcoding the paths, and preventing this driver to get a huge
amount of arrays for each board and SoC combination, also paving the
way to share the same mtk_mmsys_driver_data between multiple SoCs,
making it more straightforward to add support for new chips.

paths might be optional, see comment in mtk_drm_kms_init(). But with
this patch, you'll get an -EINVAL with a disabled path. See my
proposals how to fix that below.

I might not be understanding the reason behind allowing that but, per my logic, 
if
a board does have a path, then it's written in devicetree and enabled - 
otherwise,
it should not be there at all, in principle.

Can you explain a bit more extensively the reason(s) why we need to account
for disabled paths?


With these changes and the following two patches I was able to get
DisplayPort working on vdosys1. vdosys0 wasn't used at all.
https://lore.kernel.org/r/20240516145824.1669263-1-mwa...@kernel.org/
https://lore.kernel.org/r/20240517093024.1702750-1-mwa...@kernel.org/

I've already successfully tested a former version with DSI output on
vdosys0.

Thanks for working on this!


Thank you for helping with the testing! :-)

Cheers,
Angelo

+/**
+ * mtk_drm_of_ddp_path_build_one - Build a Display HW Pipeline for a CRTC Path
+ * @dev:          The mediatek-drm device
+ * @cpath:        CRTC Path relative to a VDO or MMSYS
+ * @out_path:     Pointer to an array that will contain the new pipeline
+ * @out_path_len: Number of entries in the pipeline array
+ *
+ * MediaTek SoCs can use different DDP hardware pipelines (or paths) depending
+ * on the board-specific desired display configuration; this function walks
+ * through all of the output endpoints starting from a VDO or MMSYS hardware
+ * instance and builds the right pipeline as specified in device trees.
+ *
+ * Return:
+ * * %0       - Display HW Pipeline successfully built and validated
+ * * %-ENOENT - Display pipeline was not specified in device tree
+ * * %-EINVAL - Display pipeline built but validation failed
+ * * %-ENOMEM - Failure to allocate pipeline array to pass to the caller
+ */
+static int mtk_drm_of_ddp_path_build_one(struct device *dev, enum 
mtk_crtc_path cpath,
+                                        const unsigned int **out_path,
+                                        unsigned int *out_path_len)
+{
+       struct device_node *next, *prev, *vdo = dev->parent->of_node;
+       unsigned int temp_path[DDP_COMPONENT_DRM_ID_MAX] = { 0 };
+       unsigned int *final_ddp_path;
+       unsigned short int idx = 0;
+       bool ovl_adaptor_comp_added = false;
+       int ret;
+
+       /* Get the first entry for the temp_path array */
+       ret = mtk_drm_of_get_ddp_ep_cid(vdo, 0, cpath, &next, &temp_path[idx]);
+       if (ret) {
+               if (next && temp_path[idx] == DDP_COMPONENT_DRM_OVL_ADAPTOR) {
+                       dev_err(dev, "Adding OVL Adaptor for %pOF\n", next);
+                       ovl_adaptor_comp_added = true;
+               } else {
+                       if (next)
+                               dev_err(dev, "Invalid component %pOF\n", next);
+                       else
+                               dev_err(dev, "Cannot find first endpoint for path 
%d\n", cpath);
+
+                       return ret;
+               }
+       }
+       idx++;
+
+       /*
+        * Walk through port outputs until we reach the last valid mediatek-drm 
component.
+        * To be valid, this must end with an "invalid" component that is a 
display node.
+        */
+       do {
+               prev = next;
+               ret = mtk_drm_of_get_ddp_ep_cid(next, 1, cpath, &next, 
&temp_path[idx]);
+               of_node_put(prev);
+               if (ret) {
+                       of_node_put(next);
+                       break;
+               }
+
+               /*
+                * If this is an OVL adaptor exclusive component and one of 
those
+                * was already added, don't add another instance of the generic
+                * DDP_COMPONENT_OVL_ADAPTOR, as this is used only to decide 
whether
+                * to probe that component master driver of which only one 
instance
+                * is needed and possible.
+                */
+               if (temp_path[idx] == DDP_COMPONENT_DRM_OVL_ADAPTOR) {
+                       if (!ovl_adaptor_comp_added)
+                               ovl_adaptor_comp_added = true;
+                       else
+                               idx--;
+               }
+       } while (++idx < DDP_COMPONENT_DRM_ID_MAX);

/* The device might not be disabled. In that case, don't check the last
  * entry but just report the missing device. */
if (ret == -ENODEV)
        return ret;

+
+       /* If the last entry is not a final display output, the configuration 
is wrong */
+       switch (temp_path[idx - 1]) {
+       case DDP_COMPONENT_DP_INTF0:
+       case DDP_COMPONENT_DP_INTF1:
+       case DDP_COMPONENT_DPI0:
+       case DDP_COMPONENT_DPI1:
+       case DDP_COMPONENT_DSI0:
+       case DDP_COMPONENT_DSI1:
+       case DDP_COMPONENT_DSI2:
+       case DDP_COMPONENT_DSI3:
+               break;
+       default:
+               dev_err(dev, "Invalid display hw pipeline. Last component: %d 
(ret=%d)\n",
+                       temp_path[idx - 1], ret);
+               return -EINVAL;
+       }
+
+       final_ddp_path = devm_kmemdup(dev, temp_path, idx * 
sizeof(temp_path[0]), GFP_KERNEL);
+       if (!final_ddp_path)
+               return -ENOMEM;
+
+       dev_dbg(dev, "Display HW Pipeline built with %d components.\n", idx);
+
+       /* Pipeline built! */
+       *out_path = final_ddp_path;
+       *out_path_len = idx;
+
+       return 0;
+}
+
+static int mtk_drm_of_ddp_path_build(struct device *dev, struct device_node 
*node,
+                                    struct mtk_mmsys_driver_data *data)
+{
+       struct device_node *ep_node;
+       struct of_endpoint of_ep;
+       bool output_present[MAX_CRTC] = { false };
+       int ret;
+
+       for_each_endpoint_of_node(node, ep_node) {
+               ret = of_graph_parse_endpoint(ep_node, &of_ep);
+               of_node_put(ep_node);
+               if (ret) {
+                       dev_err_probe(dev, ret, "Cannot parse endpoint\n");
+                       break;
+               }
+
+               if (of_ep.id >= MAX_CRTC) {
+                       ret = dev_err_probe(dev, -EINVAL,
+                                           "Invalid endpoint%u number\n", 
of_ep.port);
+                       break;
+               }
+
+               output_present[of_ep.id] = true;
+       }
+
+       if (ret)
+               return ret;
+
+       if (output_present[CRTC_MAIN]) {
+               ret = mtk_drm_of_ddp_path_build_one(dev, CRTC_MAIN,
+                                                   &data->main_path, 
&data->main_len);
+               if (ret)
if (ret && ret != -ENODEV)

+                       return ret;
+       }
+
+       if (output_present[CRTC_EXT]) {
+               ret = mtk_drm_of_ddp_path_build_one(dev, CRTC_EXT,
+                                                   &data->ext_path, 
&data->ext_len);
+               if (ret)
likewise

+                       return ret;
+       }
+
+       if (output_present[CRTC_THIRD]) {
+               ret = mtk_drm_of_ddp_path_build_one(dev, CRTC_THIRD,
+                                                   &data->third_path, 
&data->third_len);
+               if (ret)
likewise

+                       return ret;
+       }
+
+       return 0;
+}

-michael



Reply via email to