Re: [PATCH 06/15] cpufreq: cppc: Set policy->boost_supported

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

On 2025/1/24 16:58, Viresh Kumar wrote:

> With a later commit, the cpufreq core will call the ->set_boost()
> callback only if the policy supports boost frequency. The
> boost_supported flag is set by the cpufreq core if policy->freq_table is
> set and one or more boost frequencies are present.
> 
> For other drivers, the flag must be set explicitly.
> 
> With this, the local variable boost_supported isn't required anymore.
> 
> Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
> ---
>  drivers/cpufreq/cppc_cpufreq.c | 9 +--------
>  1 file changed, 1 insertion(+), 8 deletions(-)
> 
> diff --git a/drivers/cpufreq/cppc_cpufreq.c b/drivers/cpufreq/cppc_cpufreq.c
> index 7fa89b601d2a..08117fb9c1eb 100644
> --- a/drivers/cpufreq/cppc_cpufreq.c
> +++ b/drivers/cpufreq/cppc_cpufreq.c
> @@ -34,8 +34,6 @@
>   */
>  static LIST_HEAD(cpu_data_list);
>  
> -static bool boost_supported;
> -
>  static struct cpufreq_driver cppc_cpufreq_driver;
>  
>  #ifdef CONFIG_ACPI_CPPC_CPUFREQ_FIE
> @@ -653,7 +651,7 @@ static int cppc_cpufreq_cpu_init(struct cpufreq_policy *policy)
>  	 * is supported.
>  	 */
>  	if (caps->highest_perf > caps->nominal_perf)
> -		boost_supported = true;
> +		policy->boost_supported = true;
>  
>  	/* Set policy->cur to max now. The governors will adjust later. */
>  	policy->cur = cppc_perf_to_khz(caps, caps->highest_perf);
> @@ -791,11 +789,6 @@ static int cppc_cpufreq_set_boost(struct cpufreq_policy *policy, int state)
>  	struct cppc_perf_caps *caps = &cpu_data->perf_caps;
>  	int ret;
>  
> -	if (!boost_supported) {
> -		pr_err("BOOST not supported by CPU or firmware\n");
> -		return -EINVAL;
> -	}
> -
>  	if (state)
>  		policy->max = cppc_perf_to_khz(caps, caps->highest_perf);
>  	else

I have a little question. With the old boost_supported flag as false, it
will fail when you operate the global boost flag. But if you replace it
with the per-policy boost_supported flag, the global boost_enabled flag can
be set to true without any error, even no policy's boost_enabled flag
changed. Is this interface behavior change OK?