Re: [PATCH 1/5] dt-bindings: arm: Add Coresight device Trace NOC definition

[Rob Herring <robh@kernel.org>]

On Fri, Feb 21, 2025 at 03:40:28PM +0800, Yuanfang Zhang wrote:
> Adds new coresight-tnoc.yaml file describing the bindings required
> to define Trace NOC in the device trees.
> 
> Signed-off-by: Yuanfang Zhang <quic_yuanfang@quicinc.com>
> ---
>  .../bindings/arm/qcom,coresight-tnoc.yaml          | 107 +++++++++++++++++++++
>  1 file changed, 107 insertions(+)
> 
> diff --git a/Documentation/devicetree/bindings/arm/qcom,coresight-tnoc.yaml b/Documentation/devicetree/bindings/arm/qcom,coresight-tnoc.yaml
> new file mode 100644
> index 0000000000000000000000000000000000000000..b8c1aaf014fb483fd960ec55d1193fb3f66136d2
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/arm/qcom,coresight-tnoc.yaml
> @@ -0,0 +1,107 @@
> +# SPDX-License-Identifier: GPL-2.0-only OR BSD-2-Clause
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/arm/qcom,coresight-tnoc.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: Qualcomm Ttrace NOC(Network On Chip)
> +
> +maintainers:
> +  - yuanfang Zhang <quic_yuanfang@quicinc.com>
> +
> +description:
> +  The Trace NoC is an integration hierarchy which is a replacement of Dragonlink tile configuration.
> +  It brings together debug component like TPDA, funnel and interconnect Trace Noc which collects trace
> +  from subsystems and transfers to QDSS sink.
> +
> +  It sits in the different subsystem of SOC and aggregates the trace and transports it to Aggregation TNoC
> +  or to QDSS trace sink eventually. Trace NoC embeds bridges for all the interfaces(APB, ATB, QPMDA & NTS).
> +
> +  Trace NoC can take inputs from different trace sources i.e. ATB, QPMDA.

Wrap lines at 80 char. And you need '>' to preserve paragraphs.

> +
> +# Need a custom select here or 'arm,primecell' will match on lots of nodes
> +select:
> +  properties:
> +    compatible:
> +      contains:
> +        enum:
> +          - qcom,coresight-tnoc
> +  required:
> +    - compatible
> +
> +properties:
> +  $nodename:
> +    pattern: "^tn(@[0-9a-f]+)$"

blank line

> +  compatible:
> +    items:
> +      - const: qcom,coresight-tnoc
> +      - const: arm,primecell
> +
> +  reg:
> +    minItems: 1
> +    maxItems: 2

Need to describe what each entry is.

> +
> +  clocks:
> +    maxItems: 1
> +
> +  clock-names:
> +    items:
> +      - const: apb_pclk
> +
> +  in-ports:
> +    description: |

Don't need '|'

> +      Input connections from subsystem to TNoC
> +    $ref: /schemas/graph.yaml#/properties/ports

You have to define the 'port' nodes.

> +
> +  out-ports:
> +    description: |
> +      Output connections from the TNoC to Aggreg TNoC or to legacy CoreSight trace bus.
> +    $ref: /schemas/graph.yaml#/properties/ports
> +
> +    properties:
> +      port:
> +        description: |
> +          Output connections from the TNoC to Aggreg TNoC or to legacy CoreSight trace bus.

'connections' sounds like more than 1, but you only have 1 port. 

Wrap at 80 char.

> +        $ref: /schemas/graph.yaml#/properties/port
> +
> +required:
> +  - compatible
> +  - reg
> +  - clocks
> +  - clock-names
> +  - in-ports
> +  - out-ports
> +
> +additionalProperties: false
> +
> +examples:
> +  - |
> +    tn@109ab000  {
> +      compatible = "qcom,coresight-tnoc", "arm,primecell";
> +      reg = <0x0 0x109ab000  0x0 0x4200>;
> +
> +      clocks = <&aoss_qmp>;
> +      clock-names = "apb_pclk";
> +
> +      in-ports {
> +        #address-cells = <1>;
> +        #size-cells = <0>;
> +
> +        port@0 {
> +          reg = <0>;
> +
> +          tn_ag_in_tpdm_gcc: endpoint {
> +            remote-endpoint = <&tpdm_gcc_out_tn_ag>;
> +          };
> +        };
> +      };
> +
> +      out-ports {
> +        port {
> +          tn_ag_out_funnel_in1: endpoint {
> +            remote-endpoint = <&funnel_in1_in_tn_ag>;
> +          };
> +        };
> +      };
> +    };
> +...
> 
> -- 
> 2.34.1
>