Message-ID: <7195d3dd-8c39-00c5-5037-5d6d01698cf5@quicinc.com>
Date:   Mon, 27 Feb 2023 11:07:32 +0800
MIME-Version: 1.0
User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:102.0) Gecko/20100101
 Thunderbird/102.1.2
Subject: Re: [PATCH v2 1/9] dt-bindings: arm: Add support for DSB element
Content-Language: en-US
To:     Suzuki K Poulose <suzuki.poulose@arm.com>,
        Mathieu Poirier <mathieu.poirier@linaro.org>,
        Alexander Shishkin <alexander.shishkin@linux.intel.com>,
        Konrad Dybcio <konradybcio@gmail.com>,
        Mike Leach <mike.leach@linaro.org>,
        Rob Herring <robh+dt@kernel.org>,
        Krzysztof Kozlowski <krzysztof.kozlowski+dt@linaro.org>
CC:     Jinlong Mao <quic_jinlmao@quicinc.com>,
        Leo Yan <leo.yan@linaro.org>,
        "Greg Kroah-Hartman" <gregkh@linuxfoundation.org>,
        <coresight@lists.linaro.org>,
        <linux-arm-kernel@lists.infradead.org>,
        <linux-kernel@vger.kernel.org>, <devicetree@vger.kernel.org>,
        Tingwei Zhang <quic_tingweiz@quicinc.com>,
        Yuanfang Zhang <quic_yuanfang@quicinc.com>,
        Trilok Soni <quic_tsoni@quicinc.com>,
        Hao Zhang <quic_hazha@quicinc.com>,
        <linux-arm-msm@vger.kernel.org>, <bjorn.andersson@linaro.org>,
        Tao Zhang <taozha@qti.qualcomm.com>
References: <1674114105-16651-1-git-send-email-quic_taozha@quicinc.com>
 <1674114105-16651-2-git-send-email-quic_taozha@quicinc.com>
 <c55483da-8fa7-67d3-041d-930607768a2a@arm.com>
From:   Tao Zhang <quic_taozha@quicinc.com>
In-Reply-To: <c55483da-8fa7-67d3-041d-930607768a2a@arm.com>
Content-Type: text/plain; charset="UTF-8"; format=flowed
Content-Transfer-Encoding: 8bit
Precedence: bulk

Hi Suzuki,

在 2/22/2023 2:11 AM, Suzuki K Poulose 写道:
> On 19/01/2023 07:41, Tao Zhang wrote:
>> Add property "qcom,dsb-elem-size" to support DSB(Discrete Single
>> Bit) element for TPDA. Specifies the DSB element size supported
>> by each monitor connected to the aggregator on each port. Should
>> be specified in pairs (port, dsb element size).
>>
>> Signed-off-by: Tao Zhang <quic_taozha@quicinc.com>
>> Signed-off-by: Tao Zhang <taozha@qti.qualcomm.com>
>> ---
>>   .../bindings/arm/qcom,coresight-tpda.yaml          | 22 
>> ++++++++++++++++++++++
>>   1 file changed, 22 insertions(+)
>>
>> diff --git 
>> a/Documentation/devicetree/bindings/arm/qcom,coresight-tpda.yaml 
>> b/Documentation/devicetree/bindings/arm/qcom,coresight-tpda.yaml
>> index 2ec9b5b..298db7f 100644
>> --- a/Documentation/devicetree/bindings/arm/qcom,coresight-tpda.yaml
>> +++ b/Documentation/devicetree/bindings/arm/qcom,coresight-tpda.yaml
>> @@ -58,6 +58,26 @@ properties:
>>       minItems: 1
>>       maxItems: 2
>>   +  qcom,dsb-element-size:
>> +    description: |
>> +      Specifies the DSB(Discrete Single Bit) element size supported by
>> +      each monitor connected to the aggregator on each port. Should be
>> +      specified in pairs <port, dsb element size>.
>
> Isn't this a property of the TPDM connected to the port ? i.e. the DSB 
> size ? Thus shouldn't this be part of the TPDM device (and the TPDA 
> will be able to find it from the TPDM device) ?
>
Since  the port number is about the input port of TPDA, this property 
needs to be configured in the TPDA-related settings.

In our current design, TPDM doesn't have a register to record the DSB 
size, and TPDA cannot actively know the TPDM DSB size from the TPDM device.

>
> Suzuki

Best,

Tao