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

From: Gautham R . Shenoy
Date: Wed Jun 26 2024 - 01:12:01 EST


Mario Limonciello <mario.limonciello@xxxxxxx> 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@xxxxxxxxxx>
> Suggested-by: Gautham R. Shenoy <gautham.shenoy@xxxxxxx>
> Signed-off-by: Mario Limonciello <mario.limonciello@xxxxxxx>
> ---
> Cc: Sibi Sankar <quic_sibis@xxxxxxxxxxx>
> Cc: Dietmar Eggemann <dietmar.eggemann@xxxxxxx>
> Cc: Viresh Kumar <viresh.kumar@xxxxxxxxxx>
> Cc: Dhruva Gole <d-gole@xxxxxx>
> Cc: Yipeng Zou <zouyipeng@xxxxxxxxxx>
> Cc: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx>
> 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@xxxxxxx>


> ---
> 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