Re: [PATCH v3 3/3] arm: omap_hwmod disable ick autoidling when a hwmod requires that

Tero Kristo
2019-01-21T07:13:28Z

On 18/01/2019 21:45, Tony Lindgren wrote:
> * Andreas Kemnade <andreas@kemnade.info> [190118 19:39]:
>> Hi,
>>
>> On Fri, 18 Jan 2019 10:36:30 -0800
>> Tony Lindgren <tony@atomide.com> wrote:
>>
>> [...]
>>> til the next workaround.
>>>
>>>> That flags also causes the iclk being enabled/disabled
>>>> manually.
>>>
>>> Yes but SWSUP_IDLE for the interface clock to me currently
>>> just means:
>>>
>>> "manually enable and disable ocp interface clock"
>>>
>> well, if we want to manually disable it and not automatically,
>> we have to disable autoidle or it will be automatically disabled.
>>
>> Disabling it manually when it is already auto-disabled (by autoidle) is
>> just practically a no-op towards the clock.
>
> OK I buy that :) It should be probably added to the patch
> description to make it clear what it changes.
>
> Tero, any comments on this change?

Well, seeing the flag is pretty much only used for a handful of hwmods
nowadays, it should be fine. OMAP3 PM should be tested with this change
though, as there are couple of hwmods impacted on that platform. I
wonder what happens to cpuidle when display is active...

-Tero

>
>>> and with your changes it becomes:
>>>
>>> "manually enable and disable ocp interface clock and block
>>> autoidle while in use".
>>>
>>> So aren't we now changing the way things behave in general
>>> for SWSUP_IDLE?
>>>
>> Yes, we are, so proper testing is needed. But If I read those comments
>> it was always intended this way but not fully implemented because it
>> appeared to be more work like needing a usecounter (which my patchset
>> also adds) for that autoidle flag.
>
> OK yeah the use count seems necessary. I'll test here
> with my PM use cases.
>
> Regards,
>
> Tony
>

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