Re: [PATCH 1/2] cpufreq: Allow drivers to advertise boost enabled

[Gautham R.Shenoy <gautham.shenoy@amd.com>]

Mario Limonciello <mario.limonciello@amd.com> writes:

> The behavior introduced in commit f37a4d6b4a2c ("cpufreq: Fix per-policy
> boost behavior on SoCs using cpufreq_boost_set_sw()") sets up the boost
> policy incorrectly when boost has been enabled by the platform firmware
> initially even if a driver sets the policy up.
>
> This is because policy_has_boost_freq() assumes that there is a frequency
> table set up by the driver and that the boost frequencies are advertised
> in that table. This assumption doesn't work for acpi-cpufreq or
> amd-pstate. Only use this check to enable boost if it's not already
> enabled instead of also disabling it if alreayd enabled.
>
> Fixes: f37a4d6b4a2c ("cpufreq: Fix per-policy boost behavior on SoCs using cpufreq_boost_set_sw()")
> Suggested-by: Viresh Kumar <viresh.kumar@linaro.org>
> Suggested-by: Gautham R. Shenoy <gautham.shenoy@amd.com>
> Signed-off-by: Mario Limonciello <mario.limonciello@amd.com>
> ---
> Cc: Sibi Sankar <quic_sibis@quicinc.com>
> Cc: Dietmar Eggemann <dietmar.eggemann@arm.com>
> Cc: Viresh Kumar <viresh.kumar@linaro.org>
> Cc: Dhruva Gole <d-gole@ti.com>
> Cc: Yipeng Zou <zouyipeng@huawei.com>
> Cc: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
> v14->v15:
>  * Use Viresh's suggestion

This will work. The drivers that don't depend onn
policy_has_boost_freq() should ensure that they keep policy->enabled
in-sync with cpufreq_boost_enabled().

Reviewed-by: Gautham R. Shenoy <gautham.shenoy@amd.com>


> ---
>  drivers/cpufreq/cpufreq.c | 3 ++-
>  1 file changed, 2 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/cpufreq/cpufreq.c b/drivers/cpufreq/cpufreq.c
> index 1fdabb660231..270ea04fb616 100644
> --- a/drivers/cpufreq/cpufreq.c
> +++ b/drivers/cpufreq/cpufreq.c
> @@ -1430,7 +1430,8 @@ static int cpufreq_online(unsigned int cpu)
>  		}
>  
>  		/* Let the per-policy boost flag mirror the cpufreq_driver boost during init */
> -		policy->boost_enabled = cpufreq_boost_enabled() && policy_has_boost_freq(policy);
> +		if (cpufreq_boost_enabled() && policy_has_boost_freq(policy))
> +			policy->boost_enabled = true;
>  
>  		/*
>  		 * The initialization has succeeded and the policy is online.
> -- 
> 2.43.0