Re: [PATCH v4 3/3] coresight-tnoc: Add runtime PM support for Interconnect TNOC

[yuanfang zhang <yuanfang.zhang@oss.qualcomm.com>]

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On 9/1/2025 2:58 PM, 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 | 23 +++++++++++++++++++++++
>  1 file changed, 23 insertions(+)
> 
> diff --git a/drivers/hwtracing/coresight/coresight-tnoc.c b/drivers/hwtracing/coresight/coresight-tnoc.c
> index 5be882300d79bc0173aa6a19d7da1d48c4aaca9c..2c5370497076536bfa868f0d80db775ef242968b 100644
> --- a/drivers/hwtracing/coresight/coresight-tnoc.c
> +++ b/drivers/hwtracing/coresight/coresight-tnoc.c
> @@ -301,6 +301,28 @@ 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);
> +
> +	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" },
>  	{}
> @@ -314,6 +336,7 @@ static struct platform_driver itnoc_driver = {
>  		.name = "coresight-itnoc",
>  		.of_match_table = itnoc_of_match,
>  		.suppress_bind_attrs = true,
> +		.pm = &itnoc_dev_pm_ops,
>  	},
>  };
>  
> 

missed Reviewed-by: Leo Yan <leo.yan@arm.com> tag.

thanks,
yuanfang.

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