linux-kernel - Re: [PATCH 2/2] cpufreq: brcmstb-avs-cpufreq: properly retrieve P-state upon suspend

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Date:   Tue, 31 Jan 2017 10:53:01 -0800
From:   Markus Mayer <markus.mayer@...adcom.com>
To:     Viresh Kumar <viresh.kumar@...aro.org>
Cc:     Markus Mayer <code@...yer.net>,
        "Rafael J . Wysocki" <rjw@...ysocki.net>,
        Power Management List <linux-pm@...r.kernel.org>,
        Broadcom Kernel List <bcm-kernel-feedback-list@...adcom.com>,
        Linux Kernel Mailing List <linux-kernel@...r.kernel.org>
Subject: Re: [PATCH 2/2] cpufreq: brcmstb-avs-cpufreq: properly retrieve
 P-state upon suspend

On 5 January 2017 at 20:11, Viresh Kumar <viresh.kumar@...aro.org> wrote:
> On 19-12-16, 12:10, Markus Mayer wrote:
>> From: Markus Mayer <mmayer@...adcom.com>
>>
>> The AVS GET_PMAP command does return a P-state along with the P-map
>> information. However, that P-state is the initial P-state when the
>> P-map was first downloaded to AVS. It is *not* the current P-state.
>>
>> Therefore, we explicitly retrieve the P-state using the GET_PSTATE
>> command.
>>
>> Signed-off-by: Markus Mayer <mmayer@...adcom.com>
>> ---
>>  drivers/cpufreq/brcmstb-avs-cpufreq.c | 13 ++++++++++++-
>>  1 file changed, 12 insertions(+), 1 deletion(-)
>>
>> diff --git a/drivers/cpufreq/brcmstb-avs-cpufreq.c b/drivers/cpufreq/brcmstb-avs-cpufreq.c
>> index 2c6e325..c943606 100644
>> --- a/drivers/cpufreq/brcmstb-avs-cpufreq.c
>> +++ b/drivers/cpufreq/brcmstb-avs-cpufreq.c
>> @@ -784,8 +784,19 @@ static int brcm_avs_target_index(struct cpufreq_policy *policy,
>>  static int brcm_avs_suspend(struct cpufreq_policy *policy)
>>  {
>>       struct private_data *priv = policy->driver_data;
>> +     int ret;
>> +
>> +     ret = brcm_avs_get_pmap(priv, &priv->pmap);
>> +     if (ret)
>> +             return ret;
>>
>> -     return brcm_avs_get_pmap(priv, &priv->pmap);
>> +     /*
>> +      * We can't use the P-state returned by brcm_avs_get_pmap(), since
>> +      * that's the initial P-state from when the P-map was downloaded to the
>> +      * AVS co-processor, not necessarily the P-state we are running at now.
>> +      * So, we get the current P-state explicitly.
>> +      */
>> +     return brcm_avs_get_pstate(priv, &priv->pmap.state);
>>  }
>>
>>  static int brcm_avs_resume(struct cpufreq_policy *policy)
>
> Acked-by: Viresh Kumar <viresh.kumar@...aro.org>

Just wanted to follow up to see if this has been or will be picked up
for 4.10? I had a quick poke around some trees and did not see it
there.

Thanks,
-Markus