Re: [PATCH v2 2/3] dt-bindings: arm: Add Coresight Dummy Trace YAML schema
From: Hao Zhang
Date: Tue Mar 28 2023 - 07:31:04 EST
Hi Mike,
On 3/28/2023 6:12 PM, Mike Leach wrote:
Hi,
As per my comments in the previous patch in this set....
On Mon, 27 Mar 2023 at 08:38, Hao Zhang <quic_hazha@xxxxxxxxxxx> wrote:
Hi Krzysztof,
On 3/25/2023 7:49 PM, Krzysztof Kozlowski wrote:
On 24/03/2023 07:16, Hao Zhang wrote:
Add new coresight-dummy.yaml file describing the bindings required
to define coresight dummy trace in the device trees.
Subject: drop second/last, redundant "YAML schema". The "dt-bindings"
prefix is already stating that these are bindings and all new must be DT
schema. You cannot add anything else, so this is redundant.
I will take your advice to drop redundant part of title in the next
version of patch.
Signed-off-by: Hao Zhang <quic_hazha@xxxxxxxxxxx>
---
.../bindings/arm/qcom,coresight-dummy.yaml | 118 ++++++++++++++++++
1 file changed, 118 insertions(+)
create mode 100644 Documentation/devicetree/bindings/arm/qcom,coresight-dummy.yaml
diff --git a/Documentation/devicetree/bindings/arm/qcom,coresight-dummy.yaml b/Documentation/devicetree/bindings/arm/qcom,coresight-dummy.yaml
new file mode 100644
index 000000000000..7b719b084d72
--- /dev/null
+++ b/Documentation/devicetree/bindings/arm/qcom,coresight-dummy.yaml
@@ -0,0 +1,118 @@
+# SPDX-License-Identifier: GPL-2.0-only or BSD-2-Clause
+# Copyright (c) 2023 Qualcomm Innovation Center, Inc. All rights reserved.
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/arm/qcom,coresight-dummy.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: QCOM Coresight Dummy component
+
+description: |
+ The Coresight Dummy component is for the specific devices that HLOS don't have
+ permission to access or configure. Such as Coresight sink EUD, some TPDMs etc.
+ So there need driver to register dummy devices as Coresight devices. Provide
+ Coresight API for dummy device operations, such as enabling and disabling
+ dummy devices. Build the Coresight path for dummy sink or dummy source for
+ debugging.
+
+ The primary use case of the coresight dummy is to build path for dummy sink or
+ dummy source.
+
+maintainers:
+ - Mao Jinlong <quic_jinlmao@xxxxxxxxxxx>
+ - Tao Zhang <quic_taozha@xxxxxxxxxxx>
+ - Hao Zhang <quic_hazha@xxxxxxxxxxx>
+
+select:
+ properties:
+ compatible:
+ contains:
+ enum:
+ - qcom,coresight-dummy
Can we have coresight-dummy-source and coresight-dummy-sink?
Sure, I will take your advice in the next version of patch.
+ required:
+ - compatible
Why do you need the select?
This is a mistake, will remove it in the next version of patch.
+
+properties:
+ $nodename:
+ pattern: "^dummy_.*(sink|source)_[0-9]+.*$"
We do not enforce node names in individual bindings. Why do you need it?
Plus underscore is not even proper character...
I will remove this node.
+ compatible:
+ items:
Drop items. You have only one item, so no need for list.
I will take your advice and update it in the next version of patch.
+ - const: qcom,coresight-dummy
+
+ qcom,dummy-sink:
+ type: boolean
+ description:
+ Indicates that the type of this coresight node is dummy sink.
You just duplicated property name. Write something useful.
+
+ qcom,dummy-source:
+ type: boolean
+ description:
+ Indicates that the type of this coresight node is dummy source.
You just duplicated property name. Write something useful.
These properties not required if the compatible name is more specific
I will update it in the next version of patch.
Sure, I will add more details for it.
+
+ out-ports:
+ description: |
No need for |
+ Output connections from the dummy source to Coresight Trace bus.
+ $ref: /schemas/graph.yaml#/properties/ports
+
+ properties:
+ port:
+ description: Output connection from the dummy source to Coresight
+ Trace bus.
+ $ref: /schemas/graph.yaml#/properties/port
+
+ in-ports:
+ description: |
Ditto
I will remove it in the next version of patch.
+ Input connections from the CoreSight Trace bus to dummy sink.
+ $ref: /schemas/graph.yaml#/properties/ports
+
+ properties:
+ port:
+ description: Input connection from the Coresight Trace bus to
+ dummy sink.
+ $ref: /schemas/graph.yaml#/properties/port
+
+required:
+ - compatible
+
The binding should constrain out ports to dummy-source only, and in
ports to dummy sink only.
Regards
Mike
I will update it according to your advice in the next version of patch.
Thanks,
Hao
+additionalProperties: false
+
+oneOf:
+ - required:
+ - qcom,dummy-sink
+ - required:
+ - qcom,dummy-source
+
+examples:
+ # minimum dummy sink definition. dummy sink connect to coresight replicator.
+ - |
+ dummy_sink_1 {
Node names should be generic, so "sink"
https://devicetree-specification.readthedocs.io/en/latest/chapter2-devicetree-basics.html#generic-names-recommendation
+ compatible = "qcom,coresight-dummy";
+ qcom,dummy-sink;
+
+ in-ports {
+ port {
+ eud_in_replicator_swao: endpoint {
+ remote-endpoint =
+ <&replicator_swao_out_eud>;
Why line break after =?
+ };
+ };
+ };
+ };
+
+ # minimum dummy source definition. dummy source connect to coresight funnel.
If you use sentences, then start with capital letter.
I will update it according to your advice in the next version of patch.
+ - |
+ dummy_source_1 {
+ compatible = "qcom,coresight-dummy";
+ qcom,dummy-source;
+
+ out-ports {
+ port {
+ dummy_riscv_out_funnel_swao: endpoint {
+ remote-endpoint =
+ <&funnel_swao_in_dummy_riscv>;
Why line break?
I copy it from device tree and keep the original format, will correct
the format in the next version of patch.
Thanks,
Hao
+ };
+ };
+ };
+ };
+
+...
Best regards,
Krzysztof