linux-kernel - Re: [PATCH v3 3/5] dt-bindings: arm: Add Coresight TMC Control Unit hardware

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives
Hash Suite: Windows password security audit tool. GUI, reports in PDF.
[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Message-ID: <ZsKkm/Pz0GYtH2Gl@jiegan-gv.ap.qualcomm.com>
Date: Mon, 19 Aug 2024 09:49:15 +0800
From: JieGan <quic_jiegan@...cinc.com>
To: Rob Herring <robh@...nel.org>
CC: Suzuki K Poulose <suzuki.poulose@....com>,
        Mike Leach
	<mike.leach@...aro.org>,
        James Clark <james.clark@...aro.org>,
        "Alexander
 Shishkin" <alexander.shishkin@...ux.intel.com>,
        Maxime Coquelin
	<mcoquelin.stm32@...il.com>,
        Alexandre Torgue <alexandre.torgue@...s.st.com>,
        Krzysztof Kozlowski <krzk+dt@...nel.org>,
        Conor Dooley <conor+dt@...nel.org>,
        Bjorn Andersson <andersson@...nel.org>,
        Konrad Dybcio
	<konrad.dybcio@...aro.org>,
        Jinlong Mao <quic_jinlmao@...cinc.com>, <coresight@...ts.linaro.org>,
        <linux-arm-kernel@...ts.infradead.org>, <linux-kernel@...r.kernel.org>,
        <devicetree@...r.kernel.org>,
        Tingwei Zhang
	<quic_tingweiz@...cinc.com>,
        Yuanfang Zhang <quic_yuanfang@...cinc.com>,
        "Tao
 Zhang" <quic_taozha@...cinc.com>,
        Song Chai <quic_songchai@...cinc.com>, <linux-arm-msm@...r.kernel.org>,
        <linux-stm32@...md-mailman.stormreply.com>
Subject: Re: [PATCH v3 3/5] dt-bindings: arm: Add Coresight TMC Control Unit
 hardware

On Sun, Aug 18, 2024 at 08:28:34AM -0600, Rob Herring wrote:
> On Mon, Aug 12, 2024 at 10:41:39AM +0800, Jie Gan wrote:
> > Add binding file to specify how to define a Coresight TMC
> > Control Unit device in device tree.
> > 
> > It is responsible for controlling the data filter function
> > based on the source device's Trace ID for TMC ETR device.
> > The trace data with that Trace id can get into ETR's buffer
> > while other trace data gets ignored.
> > 
> > Signed-off-by: Jie Gan <quic_jiegan@...cinc.com>
> > ---
> >  .../bindings/arm/qcom,coresight-ctcu.yaml     | 79 +++++++++++++++++++
> >  1 file changed, 79 insertions(+)
> >  create mode 100644 Documentation/devicetree/bindings/arm/qcom,coresight-ctcu.yaml
> > 
> > diff --git a/Documentation/devicetree/bindings/arm/qcom,coresight-ctcu.yaml b/Documentation/devicetree/bindings/arm/qcom,coresight-ctcu.yaml
> > new file mode 100644
> > index 000000000000..7a9580007942
> > --- /dev/null
> > +++ b/Documentation/devicetree/bindings/arm/qcom,coresight-ctcu.yaml
> > @@ -0,0 +1,79 @@
> > +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
> > +%YAML 1.2
> > +---
> > +$id: http://devicetree.org/schemas/arm/qcom,coresight-ctcu.yaml#
> > +$schema: http://devicetree.org/meta-schemas/core.yaml#
> > +
> > +title: CoreSight TMC Control Unit
> > +
> > +maintainers:
> > +  - Yuanfang Zhang <quic_yuanfang@...cinc.com>
> > +  - Mao Jinlong <quic_jinlmao@...cinc.com>
> > +  - Jie Gan <quic_jiegan@...cinc.com>
> > +
> > +description:
> > +  The Coresight TMC Control unit controls various Coresight behaviors.
> > +  It works as a helper device when connected to TMC ETR device.
> > +  It is responsible for controlling the data filter function based on
> > +  the source device's Trace ID for TMC ETR device. The trace data with
> > +  that Trace id can get into ETR's buffer while other trace data gets
> > +  ignored.
> 
> Nowhere is TMC defined.
The Coresight TMC control unit(CTCU) connected to Coresight TMC device via replicator and
works as a helper device to TMC device.

The in-ports listed below illustrate their connection to TMC devices.

> 
> > +
> > +properties:
> > +  compatible:
> > +    enum:
> > +      - qcom,sa8775p-ctcu
> > +
> > +  reg:
> > +    maxItems: 1
> > +
> > +  clocks:
> > +    maxItems: 1
> > +
> > +  clock-names:
> > +    items:
> > +      - const: apb
> > +
> > +  in-ports:
> 
> Use 'ports' unless you have both in and out ports.
The ‘in-ports’ and ‘out-ports’ properties will be parsed by ‘of_coresight_get_port_parent’
and their relationships to other devices will be stored in the coresight_platform_data structure.

for example:
struct coresight_platform_data {
	int nr_inconns;
	int nr_outconns;
	struct coresight_connection **out_conns;
	struct coresight_connection **in_conns;
};

https://elixir.bootlin.com/linux/v6.11-rc4/source/drivers/hwtracing/coresight/coresight-platform.c#L147

> 
> > +    $ref: /schemas/graph.yaml#/properties/ports
> > +
> > +    patternProperties:
> > +      '^port(@[0-7])?$':
> > +        description: Input connections from CoreSight Trace bus
> > +        $ref: /schemas/graph.yaml#/properties/port
> > +
> > +required:
> > +  - compatible
> > +  - reg
> > +  - in-ports
> > +
> > +additionalProperties: false
> > +
> > +examples:
> > +  - |
> > +    ctcu@...1000 {
> > +        compatible = "qcom,sa8775p-ctcu";
> > +        reg = <0x1001000 0x1000>;
> > +
> > +        clocks = <&aoss_qmp>;
> > +        clock-names = "apb";
> > +
> > +        in-ports {
> > +            #address-cells = <1>;
> > +            #size-cells = <0>;
> > +
> > +            port@0 {
> > +                reg = <0>;
> > +                ctcu_in_port0: endpoint {
> > +                    remote-endpoint = <&etr0_out_port>;
> > +                };
> > +            };
> > +
> > +            port@1 {
> > +                reg = <1>;
> > +                ctcu_in_port1: endpoint {
> > +                    remote-endpoint = <&etr1_out_port>;
> > +                };
> > +            };
> > +        };
> > +    };
> > -- 
> > 2.34.1
> > 
> 

Thanks,
Jie