Hi Rob, > -----Original Message----- > From: Rob Herring [mailto:robh@xxxxxxxxxx] > Sent: Thursday, January 11, 2018 6:43 AM > To: Hyun Kwon <hyunk@xxxxxxxxxx> > Cc: dri-devel@xxxxxxxxxxxxxxxxxxxxx; devicetree@xxxxxxxxxxxxxxx; Michal > Simek <michal.simek@xxxxxxxxxx> > Subject: Re: [PATCH 01/10] dt-bindings: display: xlnx: Add Xilinx kms > bindings > > On Wed, Jan 10, 2018 at 8:04 PM, Hyun Kwon <hyunk@xxxxxxxxxx> wrote: > > Hi Rob, > > > > Thanks for the feedback. > > > >> -----Original Message----- > >> From: Rob Herring [mailto:robh@xxxxxxxxxx] > >> Sent: Monday, January 08, 2018 8:00 PM > >> To: Hyun Kwon <hyunk@xxxxxxxxxx> > >> Cc: dri-devel@xxxxxxxxxxxxxxxxxxxxx; devicetree@xxxxxxxxxxxxxxx; Michal > >> Simek <michal.simek@xxxxxxxxxx> > >> Subject: Re: [PATCH 01/10] dt-bindings: display: xlnx: Add Xilinx kms > >> bindings > >> > >> On Thu, Jan 04, 2018 at 06:05:50PM -0800, Hyun Kwon wrote: > >> > The dt binding for Xilinx DRM KMS driver. > >> > >> Bindings are for h/w, not drivers. > > > > I'll rephrase this. > > > >> > >> > > >> > Signed-off-by: Hyun Kwon <hyun.kwon@xxxxxxxxxx> > >> > --- > >> > .../devicetree/bindings/display/xlnx/xlnx,kms.txt | 20 > >> ++++++++++++++++++++ > >> > 1 file changed, 20 insertions(+) > >> > create mode 100644 > >> Documentation/devicetree/bindings/display/xlnx/xlnx,kms.txt > >> > > >> > diff --git > a/Documentation/devicetree/bindings/display/xlnx/xlnx,kms.txt > >> b/Documentation/devicetree/bindings/display/xlnx/xlnx,kms.txt > >> > new file mode 100644 > >> > index 0000000..8dcd552 > >> > --- /dev/null > >> > +++ b/Documentation/devicetree/bindings/display/xlnx/xlnx,kms.txt > >> > @@ -0,0 +1,20 @@ > >> > +Xilinx KMS Pipeline > >> > +------------------- > >> > + > >> > +Xilinx display pipelines can be designed with hardened video IPs and > soft > >> video > >> > +IPs in programmable logic. This KMS module provides the common > >> functionality > >> > +of individual subdevice drivers, and glue logics between them. > >> > + > >> > +Required properties: > >> > + > >> > +- compatible: Must be "xlnx,kms". > > > > I'll also rephrase the description and rename this to xlnx,display. > > > >> > + > >> > +- ports: phandles for CRTC ports, using the DT bindings defined in > >> > + Documentation/devicetree/bindings/graph.txt. > >> > >> This use of ports is not part of the graph binding. > > > > I'll add more details in the description. > > > >> > >> > + > >> > +Example: > >> > + > >> > + xlnx_drm: xlnx_drm { > >> > + compatible = "xlnx,kms"; > >> > >> drm and kms are Linuxisms. > > > > I agree. I'll remove linux subsystem specific terms. > > > >> > >> Why do you need this node? > > > > This node is used to represent a display pipeline as a single entity, which > can consist of multiple components / IPs. I'll elaborate more per your > suggestion. > > You generally don't need that. Just have the DRM driver match with the > first block in the display pipeline. Then use the OF graph to connect > to the other components in the pipeline. It would help to have a block > diagram showing the data pipelines and h/w blocks. > Some examples are as following. In simple case, a pipeline is linear with multiple blocks: ZynqMP DisplayPort pipeline: ZynqMP DMA -> ZynqMP Display controller -> ZynqMP DP encoder FPGA display pipeline where each block comes as a separate device: FPGA DMA -> FPGA mixer -> FPGA HDMI encoder It gets more interesting as those can be mixed: ZynqMP DMA -> ZynqMP Display controller -> ZynqMP DP encoder | FPAG DMA -> or ZynqMP DMA -> ZynqMP Display controller -> ZynqMP DP encoder | -> FPGA HDMI encoder Or even, ZynqMP DMA -> ZynqMP Display controller -> ZynqMP DP encoder | | FPAG DMA -> FPGA mixer -> -> FPGA HDMI encoder This node is representation of such variations as a single pipeline device. Thanks, -hyun > Rob _______________________________________________ dri-devel mailing list dri-devel@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/dri-devel
