linux-kernel - Re: [PATCH RFC 08/10] drm/panthor: devfreq: expose get_dev

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: <2489d50a-a075-42bc-92a3-7570581fe508@arm.com>
Date: Wed, 10 Sep 2025 14:59:28 +0100
From: Steven Price <steven.price@....com>
To: Nicolas Frattaroli <nicolas.frattaroli@...labora.com>,
 AngeloGioacchino Del Regno <angelogioacchino.delregno@...labora.com>,
 Boris Brezillon <boris.brezillon@...labora.com>,
 Liviu Dudau <liviu.dudau@....com>,
 Maarten Lankhorst <maarten.lankhorst@...ux.intel.com>,
 Maxime Ripard <mripard@...nel.org>, Thomas Zimmermann <tzimmermann@...e.de>,
 David Airlie <airlied@...il.com>, Simona Vetter <simona@...ll.ch>,
 Rob Herring <robh@...nel.org>, Krzysztof Kozlowski <krzk+dt@...nel.org>,
 Conor Dooley <conor+dt@...nel.org>, Matthias Brugger
 <matthias.bgg@...il.com>, MyungJoo Ham <myungjoo.ham@...sung.com>,
 Kyungmin Park <kyungmin.park@...sung.com>,
 Chanwoo Choi <cw00.choi@...sung.com>, Jassi Brar <jassisinghbrar@...il.com>,
 Kees Cook <kees@...nel.org>, "Gustavo A. R. Silva" <gustavoars@...nel.org>
Cc: Chia-I Wu <olvaffe@...il.com>, Chen-Yu Tsai <wenst@...omium.org>,
 kernel@...labora.com, dri-devel@...ts.freedesktop.org,
 devicetree@...r.kernel.org, linux-kernel@...r.kernel.org,
 linux-arm-kernel@...ts.infradead.org, linux-mediatek@...ts.infradead.org,
 linux-pm@...r.kernel.org, linux-hardening@...r.kernel.org
Subject: Re: [PATCH RFC 08/10] drm/panthor: devfreq: expose get_dev_status and
 make it more generic

On 05/09/2025 11:23, Nicolas Frattaroli wrote:
> The only device-specific part of panthor's get_dev_status devfreq
> callback is getting the clock frequency. All the other logic surrounding
> what it does may be useful for other devfreq implementations however.
> 
> Expose it in the panthor_devfreq.h header file, and make it call back
> into get_cur_freq instead of poking the common clock framework directly.
> 
> Signed-off-by: Nicolas Frattaroli <nicolas.frattaroli@...labora.com>
> ---
>  drivers/gpu/drm/panthor/panthor_devfreq.c | 29 +++++++++++++++++------------
>  drivers/gpu/drm/panthor/panthor_devfreq.h |  3 +++
>  2 files changed, 20 insertions(+), 12 deletions(-)
> 
> diff --git a/drivers/gpu/drm/panthor/panthor_devfreq.c b/drivers/gpu/drm/panthor/panthor_devfreq.c
> index 02eb3ca15d1874e1cbafc6b614b196c5cc75b6a1..d495dd856299826c4bddc205087d8914d01d7fc4 100644
> --- a/drivers/gpu/drm/panthor/panthor_devfreq.c
> +++ b/drivers/gpu/drm/panthor/panthor_devfreq.c
> @@ -43,6 +43,15 @@ static int panthor_devfreq_target(struct device *dev, unsigned long *freq,
>  	return err;
>  }
>  
> +static int panthor_devfreq_get_cur_freq(struct device *dev, unsigned long *freq)
> +{
> +	struct panthor_device *ptdev = dev_get_drvdata(dev);
> +
> +	*freq = clk_get_rate(ptdev->clks.core);
> +
> +	return 0;
> +}
> +

I don't see any reason why this was moved up here as part of this patch?
Otherwise this looks fine to me.

Thanks,
Steve

>  static void panthor_devfreq_reset(struct panthor_devfreq *pdevfreq)
>  {
>  	pdevfreq->busy_time = 0;
> @@ -50,14 +59,18 @@ static void panthor_devfreq_reset(struct panthor_devfreq *pdevfreq)
>  	pdevfreq->time_last_update = ktime_get();
>  }
>  
> -static int panthor_devfreq_get_dev_status(struct device *dev,
> -					  struct devfreq_dev_status *status)
> +int panthor_devfreq_get_dev_status(struct device *dev,
> +				   struct devfreq_dev_status *status)
>  {
>  	struct panthor_device *ptdev = dev_get_drvdata(dev);
>  	struct panthor_devfreq *pdevfreq = ptdev->devfreq;
> +	struct devfreq_dev_profile *p = pdevfreq->devfreq->profile;
>  	unsigned long irqflags;
> +	int ret;
>  
> -	status->current_frequency = clk_get_rate(ptdev->clks.core);
> +	ret = p->get_cur_freq(dev, &status->current_frequency);
> +	if (ret)
> +		return ret;
>  
>  	spin_lock_irqsave(&pdevfreq->lock, irqflags);
>  
> @@ -79,15 +92,7 @@ static int panthor_devfreq_get_dev_status(struct device *dev,
>  
>  	return 0;
>  }
> -
> -static int panthor_devfreq_get_cur_freq(struct device *dev, unsigned long *freq)
> -{
> -	struct panthor_device *ptdev = dev_get_drvdata(dev);
> -
> -	*freq = clk_get_rate(ptdev->clks.core);
> -
> -	return 0;
> -}
> +EXPORT_SYMBOL(panthor_devfreq_get_dev_status);
>  
>  static struct devfreq_dev_profile panthor_devfreq_profile = {
>  	.timer = DEVFREQ_TIMER_DELAYED,
> diff --git a/drivers/gpu/drm/panthor/panthor_devfreq.h b/drivers/gpu/drm/panthor/panthor_devfreq.h
> index e8b5ccddd45c52ee3215e9c84c6ebd9109640282..a891cb5fdc34636444f141e10f5d45828fc35b51 100644
> --- a/drivers/gpu/drm/panthor/panthor_devfreq.h
> +++ b/drivers/gpu/drm/panthor/panthor_devfreq.h
> @@ -52,6 +52,9 @@ void panthor_devfreq_suspend(struct panthor_device *ptdev);
>  void panthor_devfreq_record_busy(struct panthor_device *ptdev);
>  void panthor_devfreq_record_idle(struct panthor_device *ptdev);
>  
> +int panthor_devfreq_get_dev_status(struct device *dev,
> +				   struct devfreq_dev_status *status);
> +
>  unsigned long panthor_devfreq_get_freq(struct panthor_device *ptdev);
>  
>  #endif /* __PANTHOR_DEVFREQ_H__ */
>