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

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Message-ID: <20240131112507.fu355wnolbsoiqxn@bogus>
Date: Wed, 31 Jan 2024 11:25:07 +0000
From: Sudeep Holla <sudeep.holla@....com>
To: Sibi Sankar <quic_sibis@...cinc.com>
Cc: cristian.marussi@....com, rafael@...nel.org, viresh.kumar@...aro.org,
	Sudeep Holla <sudeep.holla@....com>, morten.rasmussen@....com,
	dietmar.eggemann@....com, lukasz.luba@....com, sboyd@...nel.org,
	linux-arm-kernel@...ts.infradead.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

On Wed, Jan 17, 2024 at 04:34:42PM +0530, 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;
> +

Can't we just use dom->sustained_freq_khz * 1000UL in both the cases ?

Other than that this series looks good to me but it would be good to
explain how you would use this. Since it is enabled by default, do you
plan to disable boost at time and when ? If it is for thermal reasons,
why your other series handling thermal and limits notification from the
firmware not sufficient.

-- 
Regards,
Sudeep