Re: [PATCH v2 4/4] cpufreq: Use policy->min/max init as QoS request

["zhenglifeng (A)" <zhenglifeng1@huawei.com>]

On 5/11/2026 9:55 PM, Pierre Gondois wrote:
> Consider policy->min/max being set in the driver .init()
> callback as a QoS request. Impacted driver are:
> - gx-suspmod.c (min)
> - cppc-cpufreq.c (min)
> - longrun.c (min/max)
> 
> Update the documentation accordingly.
> 
> Signed-off-by: Pierre Gondois <pierre.gondois@arm.com>
> ---
>  Documentation/cpu-freq/cpu-drivers.rst | 10 ++++++++--
>  drivers/cpufreq/cpufreq.c              | 12 ++++++++++--
>  2 files changed, 18 insertions(+), 4 deletions(-)
> 
> diff --git a/Documentation/cpu-freq/cpu-drivers.rst b/Documentation/cpu-freq/cpu-drivers.rst
> index c5635ac3de547..ab4f3c0f3a89b 100644
> --- a/Documentation/cpu-freq/cpu-drivers.rst
> +++ b/Documentation/cpu-freq/cpu-drivers.rst
> @@ -114,8 +114,14 @@ Then, the driver must fill in the following values:
>  |policy->cur			    | The current operating frequency of   |
>  |				    | this CPU (if appropriate)		   |
>  +-----------------------------------+--------------------------------------+
> -|policy->min,			    |					   |
> -|policy->max,			    |					   |
> +|policy->min			    | If set by the driver in ->init(),    |
> +|				    | used as initial minimum frequency	   |
> +|				    | QoS request.			   |
> ++-----------------------------------+--------------------------------------+
> +|policy->max			    | If set by the driver in ->init(),    |
> +|				    | used as initial maximum frequency	   |
> +|				    | QoS request.			   |
> ++-----------------------------------+--------------------------------------+
>  |policy->policy and, if necessary,  |					   |
>  |policy->governor		    | must contain the "default policy" for|
>  |				    | this CPU. A few moments later,       |
> diff --git a/drivers/cpufreq/cpufreq.c b/drivers/cpufreq/cpufreq.c
> index 9e2d9d3fc5351..9a005367ed87b 100644
> --- a/drivers/cpufreq/cpufreq.c
> +++ b/drivers/cpufreq/cpufreq.c
> @@ -1399,8 +1399,16 @@ static void cpufreq_policy_free(struct cpufreq_policy *policy)
>  
>  static int cpufreq_policy_init_qos(struct cpufreq_policy *policy)
>  {
> +	unsigned int min_freq, max_freq;
>  	int ret;
>  
> +	/* Use policy->min/max set by the driver as QoS requests. */
> +	min_freq = max(FREQ_QOS_MIN_DEFAULT_VALUE, policy->min);
> +	if (policy->max)
> +		max_freq = min(FREQ_QOS_MAX_DEFAULT_VALUE, policy->max);
> +	else
> +		max_freq = FREQ_QOS_MAX_DEFAULT_VALUE;
> +

Can't see the point of this. Why not just use policy->max and policy->min
to init qos?

>  	/*
>  	 * If the driver didn't set policy->min/max, set them as
>  	 * they are used to clamp frequency requests.
> @@ -1418,12 +1426,12 @@ static int cpufreq_policy_init_qos(struct cpufreq_policy *policy)
>  	}
>  
>  	ret = freq_qos_add_request(&policy->constraints, &policy->min_freq_req,
> -				   FREQ_QOS_MIN, FREQ_QOS_MIN_DEFAULT_VALUE);
> +				   FREQ_QOS_MIN, min_freq);
>  	if (ret < 0)
>  		return ret;
>  
>  	ret = freq_qos_add_request(&policy->constraints, &policy->max_freq_req,
> -				   FREQ_QOS_MAX, FREQ_QOS_MAX_DEFAULT_VALUE);
> +				   FREQ_QOS_MAX, max_freq);
>  	if (ret < 0)
>  		return ret;
>