Re: [PATCH v2 2/7] dt-bindings: interconnect: Add MediaTek EMI Interconnect bindings

[Rob Herring]

On Wed, Apr 17, 2024 at 11:14:37AM +0200, AngeloGioacchino Del Regno wrote:
> Add bindings for the MediaTek External Memory Interface Interconnect,
> which providers support system bandwidth requirements through Dynamic
> Voltage Frequency Scaling Resource Collector (DVFSRC) hardware.
> 
> This adds bindings for MediaTek MT8183 and MT8195 SoCs.
> 
> Signed-off-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@xxxxxxxxxxxxx>
> ---
>  .../interconnect/mediatek,mt8183-emi.yaml     | 76 +++++++++++++++++++
>  .../interconnect/mediatek,mt8183.h            | 23 ++++++
>  .../interconnect/mediatek,mt8195.h            | 44 +++++++++++
>  3 files changed, 143 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/interconnect/mediatek,mt8183-emi.yaml
>  create mode 100644 include/dt-bindings/interconnect/mediatek,mt8183.h
>  create mode 100644 include/dt-bindings/interconnect/mediatek,mt8195.h
> 
> diff --git a/Documentation/devicetree/bindings/interconnect/mediatek,mt8183-emi.yaml b/Documentation/devicetree/bindings/interconnect/mediatek,mt8183-emi.yaml
> new file mode 100644
> index 000000000000..3ad60fd21f83
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/interconnect/mediatek,mt8183-emi.yaml
> @@ -0,0 +1,76 @@
> +# SPDX-License-Identifier: GPL-2.0-only OR BSD-2-Clause
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/interconnect/mediatek,mt8183-emi.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: MediaTek External Memory Interface (EMI) Interconnect
> +
> +maintainers:
> +  - AngeloGioacchino Del Regno <angelogioacchino.delregno@xxxxxxxxxxxxx>
> +
> +description: |
> +  EMI interconnect providers support system bandwidth requirements through
> +  Dynamic Voltage Frequency Scaling Resource Collector (DVFSRC) hardware.
> +  The provider is able to communicate with the DVFSRC through Secure Monitor
> +  Call (SMC).
> +
> +             ICC provider         ICC Nodes
> +                              ----          ----
> +             _________       |CPU |   |--- |VPU |
> +    _____   |         |-----  ----    |     ----
> +   |     |->|  DRAM   |       ----    |     ----
> +   |DRAM |->|scheduler|----- |GPU |   |--- |DISP|
> +   |     |->|  (EMI)  |       ----    |     ----
> +   |_____|->|_________|---.   -----   |     ----
> +               /|\         `-|MMSYS|--|--- |VDEC|
> +                |             -----   |     ----
> +                |                     |     ----
> +                | change DRAM freq    |--- |VENC|
> +             --------                 |     ----
> +    SMC --> | DVFSRC |                |     ----
> +             --------                 |--- |IMG |
> +                                      |     ----
> +                                      |     ----
> +                                      |--- |CAM |
> +                                            ----
> +
> +properties:
> +  compatible:
> +    enum:
> +      - mediatek,mt8183-emi
> +      - mediatek,mt8195-emi
> +
> +  reg:
> +    maxItems: 1
> +
> +  '#interconnect-cells':
> +    const: 1
> +
> +required:
> +  - compatible
> +  - '#interconnect-cells'
> +
> +unevaluatedProperties: false
> +
> +examples:
> +  - |
> +    #include <dt-bindings/interconnect/mediatek,mt8195.h>
> +
> +    soc {
> +        #address-cells = <2>;
> +        #size-cells = <2>;
> +
> +        system-controller@10012000 {
> +            compatible = "mediatek,mt8195-dvfsrc";
> +            reg = <0 0x10012000 0 0x1000>;
> +            #address-cells = <1>;
> +            #size-cells = <0>;
> +
> +            emi_icc: interconnect@1 {
> +                compatible = "mediatek,mt8195-emi";
> +                reg = <1>;
> +                #interconnect-cells = <1>;


There's not really any need for this node. Just put #interconnect-cells 
in the parent.

Rob