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[PATCH 3/3] coresight-tnoc: Add runtime PM support for Interconnect TNOC

Yuanfang Zhang posted 3 patches 5 months, 3 weeks ago
There is a newer version of this series
[PATCH 3/3] coresight-tnoc: Add runtime PM support for Interconnect TNOC
Posted by Yuanfang Zhang 5 months, 3 weeks ago 
This patch adds runtime power management support for platform-based
CoreSight Interconnect TNOC (ITNOC) devices. It introduces suspend and
resume callbacks to manage the APB clock (`pclk`) during device runtime
transitions.

Signed-off-by: Yuanfang Zhang <yuanfang.zhang@oss.qualcomm.com>
---
 drivers/hwtracing/coresight/coresight-tnoc.c | 26 ++++++++++++++++++++++++++
 1 file changed, 26 insertions(+)

diff --git a/drivers/hwtracing/coresight/coresight-tnoc.c b/drivers/hwtracing/coresight/coresight-tnoc.c
index aa6f48d838c00d71eff22c18e34e00b93755fd82..f12a1698824bc678545319a3f482fd27e67a7352 100644
--- a/drivers/hwtracing/coresight/coresight-tnoc.c
+++ b/drivers/hwtracing/coresight/coresight-tnoc.c
@@ -270,6 +270,31 @@ static void itnoc_remove(struct platform_device *pdev)
 	pm_runtime_disable(&pdev->dev);
 }
 
+#ifdef CONFIG_PM
+static int itnoc_runtime_suspend(struct device *dev)
+{
+	struct trace_noc_drvdata *drvdata = dev_get_drvdata(dev);
+
+	clk_disable_unprepare(drvdata->pclk);
+
+	return 0;
+}
+
+static int itnoc_runtime_resume(struct device *dev)
+{
+	struct trace_noc_drvdata *drvdata = dev_get_drvdata(dev);
+	int ret;
+
+	ret = clk_prepare_enable(drvdata->pclk);
+
+	return ret;
+}
+#endif
+
+static const struct dev_pm_ops itnoc_dev_pm_ops = {
+	SET_RUNTIME_PM_OPS(itnoc_runtime_suspend, itnoc_runtime_resume, NULL)
+};
+
 static const struct of_device_id itnoc_of_match[] = {
 	{ .compatible = "qcom,coresight-itnoc" },
 	{}
@@ -282,6 +307,7 @@ static struct platform_driver itnoc_driver = {
 	.driver = {
 		.name = "coresight-itnoc",
 		.of_match_table = itnoc_of_match,
+		.pm = &itnoc_dev_pm_ops,
 	},
 };
 

-- 
2.34.1
Re: [PATCH 3/3] coresight-tnoc: Add runtime PM support for Interconnect TNOC
Posted by Leo Yan 5 months, 3 weeks ago 
On Fri, Aug 15, 2025 at 06:18:14AM -0700, Yuanfang Zhang wrote:
> This patch adds runtime power management support for platform-based
> CoreSight Interconnect TNOC (ITNOC) devices. It introduces suspend and
> resume callbacks to manage the APB clock (`pclk`) during device runtime
> transitions.
> 
> Signed-off-by: Yuanfang Zhang <yuanfang.zhang@oss.qualcomm.com>
> ---
>  drivers/hwtracing/coresight/coresight-tnoc.c | 26 ++++++++++++++++++++++++++
>  1 file changed, 26 insertions(+)
> 
> diff --git a/drivers/hwtracing/coresight/coresight-tnoc.c b/drivers/hwtracing/coresight/coresight-tnoc.c
> index aa6f48d838c00d71eff22c18e34e00b93755fd82..f12a1698824bc678545319a3f482fd27e67a7352 100644
> --- a/drivers/hwtracing/coresight/coresight-tnoc.c
> +++ b/drivers/hwtracing/coresight/coresight-tnoc.c
> @@ -270,6 +270,31 @@ static void itnoc_remove(struct platform_device *pdev)
>  	pm_runtime_disable(&pdev->dev);
>  }
>  
> +#ifdef CONFIG_PM
> +static int itnoc_runtime_suspend(struct device *dev)
> +{
> +	struct trace_noc_drvdata *drvdata = dev_get_drvdata(dev);
> +
> +	clk_disable_unprepare(drvdata->pclk);
> +
> +	return 0;
> +}
> +
> +static int itnoc_runtime_resume(struct device *dev)
> +{
> +	struct trace_noc_drvdata *drvdata = dev_get_drvdata(dev);
> +	int ret;
> +
> +	ret = clk_prepare_enable(drvdata->pclk);
> +
> +	return ret;

Here can be simplified:

    return clk_prepare_enable(drvdata->pclk);

> +}
> +#endif
> +
> +static const struct dev_pm_ops itnoc_dev_pm_ops = {
> +	SET_RUNTIME_PM_OPS(itnoc_runtime_suspend, itnoc_runtime_resume, NULL)
> +};
> +
>  static const struct of_device_id itnoc_of_match[] = {
>  	{ .compatible = "qcom,coresight-itnoc" },
>  	{}
> @@ -282,6 +307,7 @@ static struct platform_driver itnoc_driver = {
>  	.driver = {
>  		.name = "coresight-itnoc",
>  		.of_match_table = itnoc_of_match,
> +		.pm = &itnoc_dev_pm_ops,
>  	},
>  };
>  
> 
> -- 
> 2.34.1
> 
> _______________________________________________
> CoreSight mailing list -- coresight@lists.linaro.org
> To unsubscribe send an email to coresight-leave@lists.linaro.org
Re: [PATCH 3/3] coresight-tnoc: Add runtime PM support for Interconnect TNOC
Posted by yuanfang zhang 5 months, 3 weeks ago 

On 8/18/2025 10:30 PM, Leo Yan wrote:
> On Fri, Aug 15, 2025 at 06:18:14AM -0700, Yuanfang Zhang wrote:
>> This patch adds runtime power management support for platform-based
>> CoreSight Interconnect TNOC (ITNOC) devices. It introduces suspend and
>> resume callbacks to manage the APB clock (`pclk`) during device runtime
>> transitions.
>>
>> Signed-off-by: Yuanfang Zhang <yuanfang.zhang@oss.qualcomm.com>
>> ---
>>  drivers/hwtracing/coresight/coresight-tnoc.c | 26 ++++++++++++++++++++++++++
>>  1 file changed, 26 insertions(+)
>>
>> diff --git a/drivers/hwtracing/coresight/coresight-tnoc.c b/drivers/hwtracing/coresight/coresight-tnoc.c
>> index aa6f48d838c00d71eff22c18e34e00b93755fd82..f12a1698824bc678545319a3f482fd27e67a7352 100644
>> --- a/drivers/hwtracing/coresight/coresight-tnoc.c
>> +++ b/drivers/hwtracing/coresight/coresight-tnoc.c
>> @@ -270,6 +270,31 @@ static void itnoc_remove(struct platform_device *pdev)
>>  	pm_runtime_disable(&pdev->dev);
>>  }
>>  
>> +#ifdef CONFIG_PM
>> +static int itnoc_runtime_suspend(struct device *dev)
>> +{
>> +	struct trace_noc_drvdata *drvdata = dev_get_drvdata(dev);
>> +
>> +	clk_disable_unprepare(drvdata->pclk);
>> +
>> +	return 0;
>> +}
>> +
>> +static int itnoc_runtime_resume(struct device *dev)
>> +{
>> +	struct trace_noc_drvdata *drvdata = dev_get_drvdata(dev);
>> +	int ret;
>> +
>> +	ret = clk_prepare_enable(drvdata->pclk);
>> +
>> +	return ret;
> 
> Here can be simplified:
> 
>     return clk_prepare_enable(drvdata->pclk);
> 
sure, will update.
>> +}
>> +#endif
>> +
>> +static const struct dev_pm_ops itnoc_dev_pm_ops = {
>> +	SET_RUNTIME_PM_OPS(itnoc_runtime_suspend, itnoc_runtime_resume, NULL)
>> +};
>> +
>>  static const struct of_device_id itnoc_of_match[] = {
>>  	{ .compatible = "qcom,coresight-itnoc" },
>>  	{}
>> @@ -282,6 +307,7 @@ static struct platform_driver itnoc_driver = {
>>  	.driver = {
>>  		.name = "coresight-itnoc",
>>  		.of_match_table = itnoc_of_match,
>> +		.pm = &itnoc_dev_pm_ops,
>>  	},
>>  };
>>  
>>
>> -- 
>> 2.34.1
>>
>> _______________________________________________
>> CoreSight mailing list -- coresight@lists.linaro.org
>> To unsubscribe send an email to coresight-leave@lists.linaro.org

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