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Message-ID: <fb061c33-9f39-831a-76da-2fa86aaa6df6@quicinc.com>
Date:   Wed, 9 Aug 2023 14:35:25 +0800
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Subject: Re: [PATCH v7 06/13] coresight-tpdm: Add reset node to TPDM node
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>, <andersson@kernel.org>
References: <1690269353-10829-1-git-send-email-quic_taozha@quicinc.com>
 <1690269353-10829-7-git-send-email-quic_taozha@quicinc.com>
 <fc995a4a-81c5-648c-663a-4cee2cf15197@arm.com>
From:   Tao Zhang <quic_taozha@quicinc.com>
In-Reply-To: <fc995a4a-81c5-648c-663a-4cee2cf15197@arm.com>
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On 8/7/2023 5:36 PM, Suzuki K Poulose wrote:
> On 25/07/2023 08:15, Tao Zhang wrote:
>> TPDM device need a node to reset the configurations and status of
>> it. This change provides a node to reset the configurations and
>> disable the TPDM if it has been enabled.
>>
>> Signed-off-by: Tao Zhang <quic_taozha@quicinc.com>
>> ---
>>   .../ABI/testing/sysfs-bus-coresight-devices-tpdm   | 10 ++++++++++
>>   drivers/hwtracing/coresight/coresight-tpdm.c       | 22 
>> ++++++++++++++++++++++
>>   2 files changed, 32 insertions(+)
>>
>> diff --git 
>> a/Documentation/ABI/testing/sysfs-bus-coresight-devices-tpdm 
>> b/Documentation/ABI/testing/sysfs-bus-coresight-devices-tpdm
>> index 4a58e64..dbc2fbd0 100644
>> --- a/Documentation/ABI/testing/sysfs-bus-coresight-devices-tpdm
>> +++ b/Documentation/ABI/testing/sysfs-bus-coresight-devices-tpdm
>> @@ -11,3 +11,13 @@ Description:
>>           Accepts only one of the 2 values -  1 or 2.
>>           1 : Generate 64 bits data
>>           2 : Generate 32 bits data
>> +
>> +What:        /sys/bus/coresight/devices/<tpdm-name>/reset
>> +Date:        March 2023
>> +KernelVersion    6.5
>
>
>> +Contact:    Jinlong Mao (QUIC) <quic_jinlmao@quicinc.com>, Tao Zhang 
>> (QUIC) <quic_taozha@quicinc.com>
>> +Description:
>> +        (Write) Reset the dataset of the tpdm, and disable the tpdm.
>
> Please fix this, we don't disable TPDM. If it only ever resets the 
> datasets, please could we rename this as such ?
>
>  i.e., reset_dataset or reset_dsb_data ?
Sure, I will update this in the next patch series.
>
>> +
>> +        Accepts only one value -  1.
>> +        1 : Reset the dataset of the tpdm
>> diff --git a/drivers/hwtracing/coresight/coresight-tpdm.c 
>> b/drivers/hwtracing/coresight/coresight-tpdm.c
>> index 52aa48a6..acc3eea 100644
>> --- a/drivers/hwtracing/coresight/coresight-tpdm.c
>> +++ b/drivers/hwtracing/coresight/coresight-tpdm.c
>> @@ -159,6 +159,27 @@ static int tpdm_datasets_setup(struct 
>> tpdm_drvdata *drvdata)
>>       return 0;
>>   }
>>   +static ssize_t reset_store(struct device *dev,
>> +                      struct device_attribute *attr,
>> +                      const char *buf,
>> +                      size_t size)
>
> Minor nit: alignment ? Could we have something like :
>
> static ssize_t reset_store(struct device *dev,
>                struct device_attribute *attr,
>                const char *buf,
>                size_t size)
>
I will update this in the next patch series.


Best,

Tao

>
>> +{
>> +    int ret = 0;
>> +    unsigned long val;
>> +    struct tpdm_drvdata *drvdata = dev_get_drvdata(dev->parent);
>> +
>> +    ret = kstrtoul(buf, 10, &val);
>> +    if (ret || val != 1)
>> +        return -EINVAL;
>> +
>> +    spin_lock(&drvdata->spinlock);
>> +    tpdm_reset_datasets(drvdata);
>> +    spin_unlock(&drvdata->spinlock);
>> +
>> +    return size;
>> +}
>> +static DEVICE_ATTR_WO(reset);
>> +
>>   /*
>>    * value 1: 64 bits test data
>>    * value 2: 32 bits test data
>> @@ -199,6 +220,7 @@ static ssize_t integration_test_store(struct 
>> device *dev,
>>   static DEVICE_ATTR_WO(integration_test);
>>     static struct attribute *tpdm_attrs[] = {
>> +    &dev_attr_reset.attr,
>>       &dev_attr_integration_test.attr,
>>       NULL,
>>   };
>
> Suzuki
>