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Message-ID: <25966b5d-b7b0-8429-12b0-9fd394a6c25e@quicinc.com>
Date:   Thu, 27 Oct 2022 14:53:51 +0800
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Subject: Re: [PATCH 5/9] coresight-tpdm: Add nodes to set trigger timestamp
 and type
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>
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>,
        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>
References: <1662626705-13097-1-git-send-email-quic_taozha@quicinc.com>
 <1662626705-13097-6-git-send-email-quic_taozha@quicinc.com>
 <a9b090ac-b154-eef7-7872-78f7fe388f61@arm.com>
From:   Tao Zhang <quic_taozha@quicinc.com>
In-Reply-To: <a9b090ac-b154-eef7-7872-78f7fe388f61@arm.com>
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Precedence: bulk

Hi Suzuki,

在 10/24/2022 6:32 PM, Suzuki K Poulose 写道:
> On 08/09/2022 09:45, Tao Zhang wrote:
>> The nodes are needed to set or show the trigger timestamp and
>> trigger type. This change is to add these nodes to achieve these
>> function.
>>
>> Signed-off-by: Tao Zhang <quic_taozha@quicinc.com>
>> ---
>>   drivers/hwtracing/coresight/coresight-tpdm.c | 90 
>> ++++++++++++++++++++++++++++
>>   1 file changed, 90 insertions(+)
>>
>> diff --git a/drivers/hwtracing/coresight/coresight-tpdm.c 
>> b/drivers/hwtracing/coresight/coresight-tpdm.c
>> index 74cc653..fae9963 100644
>> --- a/drivers/hwtracing/coresight/coresight-tpdm.c
>> +++ b/drivers/hwtracing/coresight/coresight-tpdm.c
>> @@ -232,8 +232,98 @@ static struct attribute_group tpdm_attr_grp = {
>>       .attrs = tpdm_attrs,
>>   };
>>   +static ssize_t dsb_trig_type_show(struct device *dev,
>> +                     struct device_attribute *attr,
>> +                     char *buf)
>> +{
>> +    struct tpdm_drvdata *drvdata = dev_get_drvdata(dev->parent);
>> +
>> +    if (!(drvdata->datasets & TPDM_PIDR0_DS_DSB))
>> +        return -EPERM;
>> +
>> +    return scnprintf(buf, PAGE_SIZE, "%u\n",
>> +             (unsigned int)drvdata->dsb->trig_type);
>> +}
>> +
>> +/*
>> + * value 0: set trigger type as enablement
>> + * value 1: set trigger type as disablement
>> + */
>> +static ssize_t dsb_trig_type_store(struct device *dev,
>> +                      struct device_attribute *attr,
>> +                      const char *buf,
>> +                      size_t size)
>> +{
>> +    struct tpdm_drvdata *drvdata = dev_get_drvdata(dev->parent);
>> +    unsigned long val;
>> +
>> +    if ((kstrtoul(buf, 16, &val)) || val < 0 || val > 1)
>> +        return -EINVAL;
>> +    if (!(drvdata->datasets & TPDM_PIDR0_DS_DSB))
>> +        return -EPERM;
>> +
>> +    spin_lock(&drvdata->spinlock);
>> +    if (val)
>> +        drvdata->dsb->trig_type = true;
>> +    else
>> +        drvdata->dsb->trig_type = false;
>> +    spin_unlock(&drvdata->spinlock);
>> +    return size;
>> +}
>> +static DEVICE_ATTR_RW(dsb_trig_type);
>> +
>> +static ssize_t dsb_trig_ts_show(struct device *dev,
>> +                     struct device_attribute *attr,
>> +                     char *buf)
>> +{
>> +    struct tpdm_drvdata *drvdata = dev_get_drvdata(dev->parent);
>> +
>> +    if (!(drvdata->datasets & TPDM_PIDR0_DS_DSB))
>> +        return -EPERM;
>> +
>> +    return scnprintf(buf, PAGE_SIZE, "%u\n",
>> +             (unsigned int)drvdata->dsb->trig_ts);
>> +}
>> +
>> +/*
>> + * value 0: set trigger timestamp as enablement
>> + * value 1: set trigger timestamp as disablement
>> + */
>> +static ssize_t dsb_trig_ts_store(struct device *dev,
>> +                      struct device_attribute *attr,
>> +                      const char *buf,
>> +                      size_t size)
>> +{
>> +    struct tpdm_drvdata *drvdata = dev_get_drvdata(dev->parent);
>> +    unsigned long val;
>> +
>> +    if ((kstrtoul(buf, 16, &val)) || val < 0 || val > 1)
>> +        return -EINVAL;
>> +    if (!(drvdata->datasets & TPDM_PIDR0_DS_DSB))
>> +        return -EPERM;
>> +
>> +    spin_lock(&drvdata->spinlock);
>> +    if (val)
>> +        drvdata->dsb->trig_ts = true;
>> +    else
>> +        drvdata->dsb->trig_ts = false;
>> +    spin_unlock(&drvdata->spinlock);
>> +    return size;
>> +}
>> +static DEVICE_ATTR_RW(dsb_trig_ts);
>> +static struct attribute *tpdm_dsb_attrs[] = {
>> +    &dev_attr_dsb_trig_ts.attr,
>> +    &dev_attr_dsb_trig_type.attr,
>> +    NULL,
>> +};
>> +
>> +static struct attribute_group tpdm_dsb_attr_grp = {
>> +    .attrs = tpdm_dsb_attrs,
>> +};
>> +
>
> Please could we hide the "DSB" related knobs, if the
> the Data sets are missing using is_visible() hook ?
>
Make sense, I will update this in the next patch series.
> Suzuki
>
Best Regards
Tao