dt-bindings: arm: Add support for Coresight dummy trace

# SPDX-License-Identifier: GPL-2.0-only or BSD-2-Clause

%YAML 1.2

---

$id: http://devicetree.org/schemas/arm/arm,coresight-dummy-sink.yaml#

$schema: http://devicetree.org/meta-schemas/core.yaml#

title: ARM Coresight Dummy sink component

description: |

  CoreSight components are compliant with the ARM CoreSight architecture

  specification and can be connected in various topologies to suit a particular

  SoCs tracing needs. These trace components can generally be classified as

  sinks, links and sources. Trace data produced by one or more sources flows

  through the intermediate links connecting the source to the currently selected

  sink.

  The Coresight dummy sink component is for the specific coresight sink devices

  kernel don't have permission to access or configure, e.g., CoreSight EUD on

  Qualcomm platforms. It is a mini-USB hub implemented to support the USB-based

  debug and trace capabilities. For this device, a dummy driver is needed to

  register it as Coresight sink device in kernel side, so that path can be

  created in the driver. Then the trace flow would be transferred to EUD via

  coresight link of AP processor. It provides Coresight API for operations on

  dummy source devices, such as enabling and disabling them. It also provides

  the Coresight dummy source paths for debugging.

  The primary use case of the coresight dummy sink is to build path in kernel

  side for dummy sink component.

maintainers:

  - Mike Leach <mike.leach@linaro.org>

  - Suzuki K Poulose <suzuki.poulose@arm.com>

  - James Clark <james.clark@arm.com>

  - Mao Jinlong <quic_jinlmao@quicinc.com>

  - Hao Zhang <quic_hazha@quicinc.com>

properties:

  compatible:

    enum:

      - arm,coresight-dummy-sink

  in-ports:

    $ref: /schemas/graph.yaml#/properties/ports

    properties:

      port:

        description: Input connection from the Coresight Trace bus to

          dummy sink, such as Embedded USB debugger(EUD).

        $ref: /schemas/graph.yaml#/properties/port

required:

  - compatible

  - in-ports

additionalProperties: false

examples:

  # Minimum dummy sink definition. Dummy sink connect to coresight replicator.

  - |

    sink {

      compatible = "arm,coresight-dummy-sink";

      in-ports {

        port {

          eud_in_replicator_swao: endpoint {

            remote-endpoint = <&replicator_swao_out_eud>;

          };

        };

      };

    };

...

# SPDX-License-Identifier: GPL-2.0-only or BSD-2-Clause

%YAML 1.2

---

$id: http://devicetree.org/schemas/arm/arm,coresight-dummy-source.yaml#

$schema: http://devicetree.org/meta-schemas/core.yaml#

title: ARM Coresight Dummy source component

description: |

  CoreSight components are compliant with the ARM CoreSight architecture

  specification and can be connected in various topologies to suit a particular

  SoCs tracing needs. These trace components can generally be classified as

  sinks, links and sources. Trace data produced by one or more sources flows

  through the intermediate links connecting the source to the currently selected

  sink.

  The Coresight dummy source component is for the specific coresight source

  devices kernel don't have permission to access or configure. For some SOCs,

  there would be Coresight source trace components on sub-processor which

  are conneted to AP processor via debug bus. For these devices, a dummy driver

  is needed to register them as Coresight source devices, so that paths can be

  created in the driver. It provides Coresight API for operations on dummy

  source devices, such as enabling and disabling them. It also provides the

  Coresight dummy source paths for debugging.

  The primary use case of the coresight dummy source is to build path in kernel

  side for dummy source component.

maintainers:

  - Mike Leach <mike.leach@linaro.org>

  - Suzuki K Poulose <suzuki.poulose@arm.com>

  - James Clark <james.clark@arm.com>

  - Mao Jinlong <quic_jinlmao@quicinc.com>

  - Hao Zhang <quic_hazha@quicinc.com>

properties:

  compatible:

    enum:

      - arm,coresight-dummy-source

  out-ports:

    $ref: /schemas/graph.yaml#/properties/ports

    properties:

      port:

        description: Output connection from the source to Coresight

          Trace bus.

        $ref: /schemas/graph.yaml#/properties/port

required:

  - compatible

  - out-ports

additionalProperties: false

examples:

  # Minimum dummy source definition. Dummy source connect to coresight funnel.

  - |

    source {

      compatible = "arm,coresight-dummy-source";

      out-ports {

        port {

          dummy_riscv_out_funnel_swao: endpoint {

            remote-endpoint = <&funnel_swao_in_dummy_riscv>;

          };

        };

      };

    };

...