Re: [PATCH v4 10/24] PM / devfreq: tegra30: Don't enable consecutive-down interrupt on startup

[Dmitry Osipenko]

16.07.2019 15:17, Chanwoo Choi ÐÐÑÐÑ:
> Hi Dmitry,
> 
> On 19. 7. 8. ìì 7:32, Dmitry Osipenko wrote:
>> The consecutive-down event tells that we should perform frequency
>> de-boosting, but boosting is in a reset state on start and hence the
>> event won't do anything useful for us and it will be just a dummy
>> interrupt request.
>>
>> Signed-off-by: Dmitry Osipenko <digetx@xxxxxxxxx>
>> ---
>>  drivers/devfreq/tegra30-devfreq.c | 1 -
>>  1 file changed, 1 deletion(-)
>>
>> diff --git a/drivers/devfreq/tegra30-devfreq.c b/drivers/devfreq/tegra30-devfreq.c
>> index 32fe95458ee7..878c9396bb8c 100644
>> --- a/drivers/devfreq/tegra30-devfreq.c
>> +++ b/drivers/devfreq/tegra30-devfreq.c
>> @@ -558,7 +558,6 @@ static void tegra_actmon_configure_device(struct tegra_devfreq *tegra,
>>  		<< ACTMON_DEV_CTRL_CONSECUTIVE_ABOVE_WMARK_NUM_SHIFT;
>>  	val |= ACTMON_DEV_CTRL_AVG_ABOVE_WMARK_EN;
>>  	val |= ACTMON_DEV_CTRL_AVG_BELOW_WMARK_EN;
>> -	val |= ACTMON_DEV_CTRL_CONSECUTIVE_BELOW_WMARK_EN;
>>  	val |= ACTMON_DEV_CTRL_CONSECUTIVE_ABOVE_WMARK_EN;
>>  	val |= ACTMON_DEV_CTRL_ENB;
>>  
>>
> 
> Maybe, I think that better to review it by Thierry.
> I'm not sure it is right or not because it depend on h/w.
> 

The CONSECUTIVE_LOWER interrupts are generated if
ACTMON_DEV_CTRL_CONSECUTIVE_BELOW_WMARK_EN is enabled and ISR enables
the BELOW_WMARK_EN bit once CONSECUTIVE_UPPER event is received. The
CONSECUTIVE events are used in for the frequency boosting logic and
there is no boosting on start, hence the CONSECUTIVE_LOWER event isn't
needed on start as well. Hope this helps.