1 # SPDX-License-Identifier: GPL-2.0-only OR BSD-2-Clause
4 $id: http://devicetree.org/schemas/arm/arm,coresight-dummy-sink.yaml#
5 $schema: http://devicetree.org/meta-schemas/core.yaml#
7 title: ARM Coresight Dummy sink component
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
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.
27 The primary use case of the coresight dummy sink is to build path in kernel
28 side for dummy sink component.
31 - Mike Leach <mike.leach@linaro.org>
32 - Suzuki K Poulose <suzuki.poulose@arm.com>
33 - James Clark <james.clark@arm.com>
34 - Mao Jinlong <quic_jinlmao@quicinc.com>
35 - Hao Zhang <quic_hazha@quicinc.com>
40 - arm,coresight-dummy-sink
43 $ref: /schemas/graph.yaml#/properties/ports
47 description: Input connection from the Coresight Trace bus to
48 dummy sink, such as Embedded USB debugger(EUD).
50 $ref: /schemas/graph.yaml#/properties/port
56 additionalProperties: false
59 # Minimum dummy sink definition. Dummy sink connect to coresight replicator.
62 compatible = "arm,coresight-dummy-sink";
66 eud_in_replicator_swao: endpoint {
67 remote-endpoint = <&replicator_swao_out_eud>;