[PATCH v4 08/10] coresight: add a new function in helper_ops

Jie Gan jie.gan at oss.qualcomm.com
Tue Aug 5 17:35:24 PDT 2025



On 8/5/2025 8:30 PM, Mike Leach wrote:
> Hi,
> 
> On Fri, 25 Jul 2025 at 11:08, Jie Gan <jie.gan at oss.qualcomm.com> wrote:
>>
>> Add a new function to identifiy whether the byte-cntr function is
>> enabled or not in helper_ops.
>>
>> The byte-cntr's read_ops is expected if the byte-cntr is enabled when
>> the user try to read trace data via sysfs node.
>>
>> Signed-off-by: Jie Gan <jie.gan at oss.qualcomm.com>
>> ---
>>   .../hwtracing/coresight/coresight-ctcu-core.c | 35 +++++++++++++++++++
>>   include/linux/coresight.h                     |  3 ++
>>   2 files changed, 38 insertions(+)
>>
>> diff --git a/drivers/hwtracing/coresight/coresight-ctcu-core.c b/drivers/hwtracing/coresight/coresight-ctcu-core.c
>> index 8fc08e42187e..dec911980939 100644
>> --- a/drivers/hwtracing/coresight/coresight-ctcu-core.c
>> +++ b/drivers/hwtracing/coresight/coresight-ctcu-core.c
>> @@ -234,9 +234,44 @@ static int ctcu_disable(struct coresight_device *csdev, void *data)
>>          return ctcu_set_etr_traceid(csdev, path, false);
>>   }
>>
>> +static bool ctcu_qcom_byte_cntr_in_use(struct coresight_device *csdev,
>> +                                      void **data)
>> +{
>> +       struct ctcu_byte_cntr *byte_cntr_data;
>> +       struct coresight_device *helper;
>> +       struct ctcu_drvdata *drvdata;
>> +       int port;
>> +
>> +       if (!csdev)
>> +               return false;
>> +
>> +       helper = coresight_get_helper(csdev, CORESIGHT_DEV_SUBTYPE_HELPER_CTCU);
>> +       if (!helper)
>> +               return false;
>> +
>> +       port = coresight_get_in_port_dest(csdev, helper);
>> +       if (port < 0)
>> +               return false;
>> +
>> +       drvdata = dev_get_drvdata(helper->dev.parent);
>> +       /* Something wrong when initialize byte_cntr_read_ops */
>> +       if (!drvdata->byte_cntr_read_ops)
>> +               return false;
>> +
>> +       byte_cntr_data = &drvdata->byte_cntr_data[port];
>> +       /* Return the pointer of the ctcu_drvdata if byte-cntr has enabled */
>> +       if (byte_cntr_data && byte_cntr_data->thresh_val) {
>> +               *data = (void *)drvdata->byte_cntr_read_ops;
>> +               return true;
>> +       }
>> +
>> +       return false;
>> +}
>> +
>>   static const struct coresight_ops_helper ctcu_helper_ops = {
>>          .enable = ctcu_enable,
>>          .disable = ctcu_disable,
>> +       .qcom_byte_cntr_in_use = ctcu_qcom_byte_cntr_in_use,
> 
> These ops structures are for generic functions used throughout the
> devices. Do not put this function here.
> 
> This is a specific ctcu helper. Make it external to the file and
> declare it in coresight-ctcu.h

Will address the comment in next version.

Thanks,
Jie

> 
> Mike
> 
>>   };
>>
>>   static const struct coresight_ops ctcu_ops = {
>> diff --git a/include/linux/coresight.h b/include/linux/coresight.h
>> index 4ac65c68bbf4..b5f052854b08 100644
>> --- a/include/linux/coresight.h
>> +++ b/include/linux/coresight.h
>> @@ -419,11 +419,14 @@ struct coresight_ops_source {
>>    *
>>    * @enable     : Enable the device
>>    * @disable    : Disable the device
>> + * @qcom_byte_cntr_in_use:     check whether the byte-cntr is enabled.
>>    */
>>   struct coresight_ops_helper {
>>          int (*enable)(struct coresight_device *csdev, enum cs_mode mode,
>>                        void *data);
>>          int (*disable)(struct coresight_device *csdev, void *data);
>> +       bool (*qcom_byte_cntr_in_use)(struct coresight_device *csdev,
>> +                                     void **data);
>>   };
>>
>>
>> --
>> 2.34.1
>>
> 
> 




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