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

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20250818143011.GB8071@e132581.arm.com>
Date: Mon, 18 Aug 2025 15:30:11 +0100
From: Leo Yan <leo.yan@....com>
To: Yuanfang Zhang <yuanfang.zhang@....qualcomm.com>
Cc: Suzuki K Poulose <suzuki.poulose@....com>,
	Mike Leach <mike.leach@...aro.org>,
	James Clark <james.clark@...aro.org>, Rob Herring <robh@...nel.org>,
	Krzysztof Kozlowski <krzk+dt@...nel.org>,
	Conor Dooley <conor+dt@...nel.org>,
	Alexander Shishkin <alexander.shishkin@...ux.intel.com>,
	kernel@....qualcomm.com, coresight@...ts.linaro.org,
	linux-arm-kernel@...ts.infradead.org, linux-arm-msm@...r.kernel.org,
	devicetree@...r.kernel.org, linux-kernel@...r.kernel.org
Subject: Re: [PATCH 3/3] coresight-tnoc: Add runtime PM support for
 Interconnect TNOC

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@....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@...ts.linaro.org
> To unsubscribe send an email to coresight-leave@...ts.linaro.org