1# SPDX-License-Identifier: GPL-2.0-only OR BSD-2-Clause 2%YAML 1.2 3--- 4$id: http://devicetree.org/schemas/arm/arm,coresight-dummy-sink.yaml# 5$schema: http://devicetree.org/meta-schemas/core.yaml# 6 7title: ARM Coresight Dummy sink component 8 9description: | 10 CoreSight components are compliant with the ARM CoreSight architecture 11 specification and can be connected in various topologies to suit a particular 12 SoCs tracing needs. These trace components can generally be classified as 13 sinks, links and sources. Trace data produced by one or more sources flows 14 through the intermediate links connecting the source to the currently selected 15 sink. 16 17 The Coresight dummy sink component is for the specific coresight sink devices 18 kernel don't have permission to access or configure, e.g., CoreSight EUD on 19 Qualcomm platforms. It is a mini-USB hub implemented to support the USB-based 20 debug and trace capabilities. For this device, a dummy driver is needed to 21 register it as Coresight sink device in kernel side, so that path can be 22 created in the driver. Then the trace flow would be transferred to EUD via 23 coresight link of AP processor. It provides Coresight API for operations on 24 dummy source devices, such as enabling and disabling them. It also provides 25 the Coresight dummy source paths for debugging. 26 27 The primary use case of the coresight dummy sink is to build path in kernel 28 side for dummy sink component. 29 30maintainers: 31 - Mike Leach <mike.leach@linaro.org> 32 - Suzuki K Poulose <suzuki.poulose@arm.com> 33 - James Clark <james.clark@linaro.org> 34 - Mao Jinlong <quic_jinlmao@quicinc.com> 35 - Hao Zhang <quic_hazha@quicinc.com> 36 37properties: 38 compatible: 39 enum: 40 - arm,coresight-dummy-sink 41 42 in-ports: 43 $ref: /schemas/graph.yaml#/properties/ports 44 45 properties: 46 port: 47 description: Input connection from the Coresight Trace bus to 48 dummy sink, such as Embedded USB debugger(EUD). 49 50 $ref: /schemas/graph.yaml#/properties/port 51 52required: 53 - compatible 54 - in-ports 55 56additionalProperties: false 57 58examples: 59 # Minimum dummy sink definition. Dummy sink connect to coresight replicator. 60 - | 61 sink { 62 compatible = "arm,coresight-dummy-sink"; 63 64 in-ports { 65 port { 66 eud_in_replicator_swao: endpoint { 67 remote-endpoint = <&replicator_swao_out_eud>; 68 }; 69 }; 70 }; 71 }; 72 73... 74