Re: [PATCH 4/7] dt-bindings: display: allwinner: Add DE33 planes

Jernej Škrabec
2025-11-16T11:44:11Z

Hi!

Dne nedelja, 16. november 2025 ob 12:29:27 Srednjeevropski standardni čas je Krzysztof Kozlowski napisal(a):
> On Sat, Nov 15, 2025 at 03:13:44PM +0100, Jernej Skrabec wrote:
> > Allwinner Display Engine 3.3 contains planes, which are shared resources
> > between all mixers present in SoC. They can be assigned to specific
> > mixer by using registers which reside in display clocks MMIO.
> >
> > Add a binding for them.
> >
> > Signed-off-by: Jernej Skrabec <jernej.skrabec@gmail.com>
> > ---
> > .../allwinner,sun50i-h616-de33-planes.yaml | 44 +++++++++++++++++++
> > 1 file changed, 44 insertions(+)
> > create mode 100644 Documentation/devicetree/bindings/display/allwinner,sun50i-h616-de33-planes.yaml
> >
> > diff --git a/Documentation/devicetree/bindings/display/allwinner,sun50i-h616-de33-planes.yaml b/Documentation/devicetree/bindings/display/allwinner,sun50i-h616-de33-planes.yaml
> > new file mode 100644
> > index 000000000000..801e5068a6b5
> > --- /dev/null
> > +++ b/Documentation/devicetree/bindings/display/allwinner,sun50i-h616-de33-planes.yaml
> > @@ -0,0 +1,44 @@
> > +# SPDX-License-Identifier: GPL-2.0-only OR BSD-2-Clause
> > +%YAML 1.2
> > +---
> > +$id: http://devicetree.org/schemas/display/allwinner,sun50i-h616-de33-planes.yaml#
> > +$schema: http://devicetree.org/meta-schemas/core.yaml#
> > +
> > +title: Allwinner H616 Display Engine 3.3 planes
> > +
> > +maintainers:
> > + - Jernej Skrabec <jernej.skrabec@gmail.com>
> > +
> > +description: |
>
> Do not need '|' unless you need to preserve formatting.
>
> > + Display Engine 3.3 planes are independent of mixers, contrary to
> > + previous generations of Display Engine. Planes can be assigned to
> > + mixers independently and even dynamically during runtime.
> > +
> > +properties:
> > + compatible:
> > + enum:
> > + - allwinner,sun50i-h616-de33-planes
> > +
> > + reg:
> > + maxItems: 1
> > +
> > + allwinner,plane-mapping:
> > + $ref: /schemas/types.yaml#/definitions/phandle
> > + description: Phandle of Display Engine clock node
>
> You description is almost duplicating property name. You need to explain
> here how this device uses them.

So I guess I can copy commit description here? It is needed to
access registers from different core, so it can assign (map)
planes between mixers at runtime.

>
> Esxpecially that clocks do not go via custom properties.

This has nothing to do with clocks per se, it's just that registers
that driver needs to access for mapping planes between mixers
are in IP core which takes care mostly for clocks and resets.

Best regards,
Jernej

>
> Best regards,
> Krzysztof
>
>