Re: [PATCH v2 1/6] dt-bindings: display: Add yamls for JH7110 display system

From: Krzysztof Kozlowski
Date: Wed Oct 25 2023 - 08:50:41 EST

On 25/10/2023 12:39, Keith Zhao wrote:
> StarFive SoCs JH7110 display system:

A nit, subject: drop second/last, redundant "yamls for". The
"dt-bindings" prefix is already stating that these are bindings, so
format is fixed.

> lcd-controller bases verisilicon dc8200 IP,
> and hdmi bases Innosilicon IP. Add bindings for them.

Please make it a proper sentences, with proper wrapping.

>
> also update MAINTAINERS for dt-bindings

Not a sentence, but also not really needed.

>
> about this patch, I tested the dtbs_check and dt_binding_check
> with the result pass.
> Based on the feedback of the previous version, the corresponding arrangement is made

Not relevant, so not really suitable for commit msg.

>
> Signed-off-by: Keith Zhao <keith.zhao@xxxxxxxxxxxxxxxx>
> ---
> .../starfive/starfive,display-subsystem.yaml | 41 +++++++
> .../starfive/starfive,jh7110-dc8200.yaml | 109 ++++++++++++++++++
> .../starfive/starfive,jh7110-inno-hdmi.yaml | 85 ++++++++++++++
> MAINTAINERS | 7 ++
> 4 files changed, 242 insertions(+)
> create mode 100644 Documentation/devicetree/bindings/display/starfive/starfive,display-subsystem.yaml
> create mode 100644 Documentation/devicetree/bindings/display/starfive/starfive,jh7110-dc8200.yaml
> create mode 100644 Documentation/devicetree/bindings/display/starfive/starfive,jh7110-inno-hdmi.yaml
>
> diff --git a/Documentation/devicetree/bindings/display/starfive/starfive,display-subsystem.yaml b/Documentation/devicetree/bindings/display/starfive/starfive,display-subsystem.yaml
> new file mode 100644
> index 000000000..f45b97b08
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/display/starfive/starfive,display-subsystem.yaml
> @@ -0,0 +1,41 @@
> +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/display/starfive/starfive,display-subsystem.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: Starfive DRM master device

What is DRM in hardware? I know Digital Rights Management, but then
subsystem seems wrong. If you mean Linux DRM, then Linux is not a
hardware, so drop all Linuxisms and describe hardware.


> +
> +maintainers:
> + - Keith Zhao <keith.zhao@xxxxxxxxxxxxxxxx>
> + - ShengYang Chen <shengyang.chen@xxxxxxxxxxxxxxxx>
> +
> +description:
> + The Starfive DRM master device is a virtual device needed to list all

Virtual device? Then not suitable for bindings, sorry.

> + display controller or other display interface nodes that comprise the
> + graphics subsystem.
> +
> +properties:
> + compatible:
> + const: starfive,display-subsystem
> +
> + ports:
> + $ref: /schemas/types.yaml#/definitions/phandle-array

No, ports is not phandle-array. ports is object, always.

> + description:
> + Should contain a list of phandles pointing to display interface ports
> + of display controller devices. Display controller definitions as defined
> + in Documentation/devicetree/bindings/display/starfive/
> + starfive,jh7110-dc8200.yaml

Use standard graph ports, not some own, custom property.

Anyway, entire binding should be dropped. You do not need it even.

> +
> +required:
> + - compatible
> + - ports
> +
> +additionalProperties: false
> +
> +examples:
> + - |
> + display-subsystem {
> + compatible = "starfive,display-subsystem";
> + ports = <&dc_out>;
> + };
> diff --git a/Documentation/devicetree/bindings/display/starfive/starfive,jh7110-dc8200.yaml b/Documentation/devicetree/bindings/display/starfive/starfive,jh7110-dc8200.yaml
> new file mode 100644
> index 000000000..87051cddf
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/display/starfive/starfive,jh7110-dc8200.yaml
> @@ -0,0 +1,109 @@
> +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/display/starfive/starfive,jh7110-dc8200.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: StarFive display controller
> +
> +description:
> + The StarFive SoC uses the display controller based on Verisilicon IP
> + to transfer the image data from a video memory buffer to an external
> + LCD interface.
> +
> +maintainers:
> + - Keith Zhao <keith.zhao@xxxxxxxxxxxxxxxx>
> +
> +properties:
> + compatible:
> + const: starfive,jh7110-dc8200
> +
> + reg:
> + minItems: 1
> + items:
> + - description:
> + host interface

In one line.
- description: host interface

> + - description:
> + display physical base address and length.

Drop redundant parts: base address and length. Everything in reg for
MMIO would have it...

> +
> + interrupts:
> + items:
> + - description: The interrupt will be generated when DC finish one frame
> +
> + clocks:
> + items:
> + - description: Clock for display system noc bus.
> + - description: Pixel clock for display channel 0.
> + - description: Pixel clock for display channel 1.
> + - description: Core clock for display controller.
> + - description: Clock for axi bus to access ddr.
> + - description: Clock for ahb bus to R/W the phy regs.
> + - description: External HDMI pixel clock.
> + - description: Parent clock for pixel clock
> +
> + clock-names:
> + items:
> + - const: noc_bus
> + - const: channel0
> + - const: channel1
> + - const: dc_core
> + - const: axi_core
> + - const: ahb
> + - const: hdmi_tx
> + - const: dc_parent
> +
> + resets:
> + items:
> + - description: Reset for axi bus.
> + - description: Reset for ahb bus.
> + - description: Core reset of display controller.
> +
> + reset-names:
> + items:
> + - const: axi
> + - const: ahb
> + - const: core
> +
> + port:
> + $ref: /schemas/graph.yaml#/properties/port
> +
> +required:
> + - compatible
> + - reg
> + - interrupts
> + - clocks
> + - clock-names
> + - resets
> + - reset-names
> + - port
> +
> +additionalProperties: false
> +
> +examples:
> + - |
> + dc8200: lcd-controller@29400000 {
> + compatible = "starfive,jh7110-dc8200";
> + reg = <0x29400000 0x100>, <0x29400800 0x2000>;
> + interrupts = <95>;
> + clocks = <&syscrg 60>,
> + <&voutcrg 7>,
> + <&voutcrg 8>,
> + <&voutcrg 4>,
> + <&voutcrg 5>,
> + <&voutcrg 6>,
> + <&hdmitx0_pixelclk>,
> + <&voutcrg 1>;
> + clock-names = "noc_bus", "channel0", "channel1",
> + "dc_core", "axi_core", "ahb",
> + "hdmi_tx","dc_parent";
> + resets = <&voutcrg 0>, <&voutcrg 1>, <&voutcrg 2>;
> + reset-names = "axi", "ahb", "core";
> + dc_out: port {
> + #address-cells = <1>;
> + #size-cells = <0>;
> + dc_out_hdmi: endpoint@0 {
> + reg = <0>;
> + remote-endpoint = <&hdmi_in_dc>;
> + };
> + };
> + };
> diff --git a/Documentation/devicetree/bindings/display/starfive/starfive,jh7110-inno-hdmi.yaml b/Documentation/devicetree/bindings/display/starfive/starfive,jh7110-inno-hdmi.yaml
> new file mode 100644
> index 000000000..f6c473a10
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/display/starfive/starfive,jh7110-inno-hdmi.yaml
> @@ -0,0 +1,85 @@
> +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/display/starfive/starfive,jh7110-inno-hdmi.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: Starfive JH7110 HDMI controller
> +
> +description:
> + The StarFive JH7110 SoC uses the HDMI signal transmiter based on innosilicon IP
> + to generate HDMI signal from its input and transmit the signal to the screen.
> +
> +maintainers:
> + - Keith Zhao <keith.zhao@xxxxxxxxxxxxxxxx>
> +
> +properties:
> + compatible:
> + const: "starfive,jh7110-inno-hdmi"

It does not look like you tested the bindings, at least after quick
look. Please run `make dt_binding_check` (see
Documentation/devicetree/bindings/writing-schema.rst for instructions).
Maybe you need to update your dtschema and yamllint.

Best regards,
Krzysztof