linux-kernel - Re: [PATCH 2/3] firmware: arm_scmi: Add support for marking certain frequencies as boost

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: <e3abe1ab-064f-4a6a-a91d-fe8c91574600@arm.com>
Date: Wed, 31 Jan 2024 15:29:43 +0100
From: Pierre Gondois <pierre.gondois@....com>
To: Sibi Sankar <quic_sibis@...cinc.com>, cristian.marussi@....com
Cc: linux-arm-kernel@...ts.infradead.org, sudeep.holla@....com,
 sboyd@...nel.org, lukasz.luba@....com, dietmar.eggemann@....com,
 morten.rasmussen@....com, viresh.kumar@...aro.org, rafael@...nel.org,
 linux-pm@...r.kernel.org, linux-kernel@...r.kernel.org,
 quic_mdtipton@...cinc.com, linux-arm-msm@...r.kernel.org, nm@...com
Subject: Re: [PATCH 2/3] firmware: arm_scmi: Add support for marking certain
 frequencies as boost

Hello Sibi,

On 1/17/24 12:04, Sibi Sankar wrote:
> All opps above the sustained level/frequency are treated as boost, so mark
> them accordingly.
> 
> Suggested-by: Sudeep Holla <sudeep.holla@....com>
> Signed-off-by: Sibi Sankar <quic_sibis@...cinc.com>
> ---
>   drivers/firmware/arm_scmi/perf.c | 11 ++++++++++-
>   1 file changed, 10 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/firmware/arm_scmi/perf.c b/drivers/firmware/arm_scmi/perf.c
> index e286f04ee6e3..d3fb8c804b3d 100644
> --- a/drivers/firmware/arm_scmi/perf.c
> +++ b/drivers/firmware/arm_scmi/perf.c
> @@ -811,7 +811,7 @@ static int scmi_dvfs_device_opps_add(const struct scmi_protocol_handle *ph,
>   				     struct device *dev, u32 domain)
>   {
>   	int idx, ret;
> -	unsigned long freq;
> +	unsigned long freq, sustained_freq;
>   	struct dev_pm_opp_data data = {};
>   	struct perf_dom_info *dom;
>   
> @@ -819,12 +819,21 @@ static int scmi_dvfs_device_opps_add(const struct scmi_protocol_handle *ph,
>   	if (IS_ERR(dom))
>   		return PTR_ERR(dom);
>   
> +	if (!dom->level_indexing_mode)
> +		sustained_freq = dom->sustained_perf_level * dom->mult_factor;
> +	else
> +		sustained_freq = dom->sustained_freq_khz * dom->mult_factor;
> +
>   	for (idx = 0; idx < dom->opp_count; idx++) {
>   		if (!dom->level_indexing_mode)
>   			freq = dom->opp[idx].perf * dom->mult_factor;
>   		else
>   			freq = dom->opp[idx].indicative_freq * dom->mult_factor;
>   
> +		/* All opps above the sustained level/frequency are treated as boost */
> +		if (sustained_freq && freq > sustained_freq)

It seems the sustained_freq is not optional since SCMI v1.0,
is it necessary to check that (sustained_freq != 0) ?

> +			data.turbo = true;
> +
>   		data.level = dom->opp[idx].perf;
>   		data.freq = freq;
>