linux/Documentation/devicetree/bindings/arm/ete.yaml
Suzuki K Poulose e7cc4f2303 dts: bindings: Document device tree bindings for ETE
Document the device tree bindings for Embedded Trace Extensions.
ETE can be connected to legacy coresight components and thus
could optionally contain a connection graph as described by
the CoreSight bindings.

Cc: devicetree@vger.kernel.org
Cc: Mathieu Poirier <mathieu.poirier@linaro.org>
Cc: Mike Leach <mike.leach@linaro.org>
Reviewed-by: Rob Herring <robh@kernel.org>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Link: https://lore.kernel.org/r/20210405164307.1720226-15-suzuki.poulose@arm.com
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
2021-04-06 16:05:38 -06:00

76 lines
2.1 KiB
YAML

# SPDX-License-Identifier: GPL-2.0-only or BSD-2-Clause
# Copyright 2021, Arm Ltd
%YAML 1.2
---
$id: "http://devicetree.org/schemas/arm/ete.yaml#"
$schema: "http://devicetree.org/meta-schemas/core.yaml#"
title: ARM Embedded Trace Extensions
maintainers:
- Suzuki K Poulose <suzuki.poulose@arm.com>
- Mathieu Poirier <mathieu.poirier@linaro.org>
description: |
Arm Embedded Trace Extension(ETE) is a per CPU trace component that
allows tracing the CPU execution. It overlaps with the CoreSight ETMv4
architecture and has extended support for future architecture changes.
The trace generated by the ETE could be stored via legacy CoreSight
components (e.g, TMC-ETR) or other means (e.g, using a per CPU buffer
Arm Trace Buffer Extension (TRBE)). Since the ETE can be connected to
legacy CoreSight components, a node must be listed per instance, along
with any optional connection graph as per the coresight bindings.
See bindings/arm/coresight.txt.
properties:
$nodename:
pattern: "^ete([0-9a-f]+)$"
compatible:
items:
- const: arm,embedded-trace-extension
cpu:
description: |
Handle to the cpu this ETE is bound to.
$ref: /schemas/types.yaml#/definitions/phandle
out-ports:
description: |
Output connections from the ETE to legacy CoreSight trace bus.
$ref: /schemas/graph.yaml#/properties/ports
properties:
port:
description: Output connection from the ETE to legacy CoreSight Trace bus.
$ref: /schemas/graph.yaml#/properties/port
required:
- compatible
- cpu
additionalProperties: false
examples:
# An ETE node without legacy CoreSight connections
- |
ete0 {
compatible = "arm,embedded-trace-extension";
cpu = <&cpu_0>;
};
# An ETE node with legacy CoreSight connections
- |
ete1 {
compatible = "arm,embedded-trace-extension";
cpu = <&cpu_1>;
out-ports { /* legacy coresight connection */
port {
ete1_out_port: endpoint {
remote-endpoint = <&funnel_in_port0>;
};
};
};
};
...