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

[Tero Kristo]

On 18/01/2019 21:45, Tony Lindgren wrote:
> * Andreas Kemnade <andreas@xxxxxxxxxxxx> [190118 19:39]:
> > Hi,
> >
> > On Fri, 18 Jan 2019 10:36:30 -0800
> > Tony Lindgren <tony@xxxxxxxxxxx> 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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