On Wed, Jan 13, 2021 at 09:48:13AM +0530, Anshuman Khandual wrote: > From: Suzuki K Poulose <suzuki.poulose@xxxxxxx> > > 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@xxxxxxxxxxxxxxx > Cc: Mathieu Poirier <mathieu.poirier@xxxxxxxxxx> > Cc: Mike Leach <mike.leach@xxxxxxxxxx> > Cc: Rob Herring <robh@xxxxxxxxxx> > Signed-off-by: Suzuki K Poulose <suzuki.poulose@xxxxxxx> > Signed-off-by: Anshuman Khandual <anshuman.khandual@xxxxxxx> > --- > Documentation/devicetree/bindings/arm/ete.yaml | 71 ++++++++++++++++++++++++++ > 1 file changed, 71 insertions(+) > create mode 100644 Documentation/devicetree/bindings/arm/ete.yaml > > diff --git a/Documentation/devicetree/bindings/arm/ete.yaml b/Documentation/devicetree/bindings/arm/ete.yaml > new file mode 100644 > index 0000000..00e6a77 > --- /dev/null > +++ b/Documentation/devicetree/bindings/arm/ete.yaml > @@ -0,0 +1,71 @@ > +# 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@xxxxxxx> > + - Mathieu Poirier <mathieu.poirier@xxxxxxxxxx> > + > +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: We use 'cpus' in a couple of other places, let's do that here for consistency. > + description: | > + Handle to the cpu this ETE is bound to. > + $ref: /schemas/types.yaml#/definitions/phandle > + > + out-ports: > + description: | > + Out put connections from the ETE to legacy CoreSight trace bus. Output > + $ref: /schemas/graph.yaml#/properties/ports You have to define what each 'port' is if there can be more than 1. If there's only ever 1 then you just need 'port' though maybe all the coresight bindings require 'out-ports'. And the port nodes need a $ref to '/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>; > + }; > + }; > + }; > + }; > + > +... > -- > 2.7.4 >
