linux-kernel - Re: [PATCH v2 1/2] cpufreq: Allow drivers to advertise boost enabled

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Message-ID: <5ed06d29-a8b6-48f6-b341-3cd32c19c8d7@amd.com>
Date: Thu, 27 Jun 2024 14:11:53 -0500
From: Mario Limonciello <mario.limonciello@....com>
To: "Rafael J. Wysocki" <rafael@...nel.org>
Cc: linux-pm@...r.kernel.org, linux-kernel@...r.kernel.org,
 Sibi Sankar <quic_sibis@...cinc.com>, Dhruva Gole <d-gole@...com>,
 Viresh Kumar <viresh.kumar@...aro.org>,
 "Gautham R . Shenoy" <gautham.shenoy@....com>,
 Dietmar Eggemann <dietmar.eggemann@....com>,
 Yipeng Zou <zouyipeng@...wei.com>,
 "Rafael J . Wysocki" <rafael.j.wysocki@...el.com>
Subject: Re: [PATCH v2 1/2] cpufreq: Allow drivers to advertise boost enabled

On 6/27/2024 04:59, Rafael J. Wysocki wrote:
> On Wed, Jun 26, 2024 at 10:47 PM Mario Limonciello
> <mario.limonciello@....com> wrote:
>>
>> 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.
>>
>> Reviewed-by: Sibi Sankar <quic_sibis@...cinc.com>
>> Reviewed-by: Dhruva Gole <d-gole@...com>
>> Acked-by: Viresh Kumar <viresh.kumar@...aro.org>
>> Reviewed-by: Gautham R. Shenoy <gautham.shenoy@....com>
>> Fixes: f37a4d6b4a2c ("cpufreq: Fix per-policy boost behavior on SoCs using cpufreq_boost_set_sw()")
> 
> CC: stable I suppose?

Yes, I didn't realize f37a4d6b4a2c came in 6.9, I had assumed it was 
6.10.  But since it's 6.9, yes if you can please add stable tag when 
committing.

> 
>> Suggested-by: Viresh Kumar <viresh.kumar@...aro.org>
>> Suggested-by: Gautham R. Shenoy <gautham.shenoy@....com>
>> Signed-off-by: Mario Limonciello <mario.limonciello@....com>
>> ---
>> Cc: Sibi Sankar <quic_sibis@...cinc.com>
>> Cc: Dietmar Eggemann <dietmar.eggemann@....com>
>> Cc: Viresh Kumar <viresh.kumar@...aro.org>
>> Cc: Dhruva Gole <d-gole@...com>
>> Cc: Yipeng Zou <zouyipeng@...wei.com>
>> Cc: Rafael J. Wysocki <rafael.j.wysocki@...el.com>
>> v1->v2
>>   * Pick up tags
>> ---
>>   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.
>> --