Re: community PM requirements/issues and PowerOP [Was: Re: So, what's the status on the recent patches here?]

Matthew Locke
2006-09-11T20:25:42Z

On Sep 11, 2006, at 1:06 PM, Pavel Machek wrote:

> On Mon 2006-09-11 12:53:27, Matthew Locke wrote:
>> On Sep 11, 2006, at 12:36 PM, Pavel Machek wrote:
>>
>>>>> You did echo low > something to change CPU frequency, IIRC.
>>>> My patch set presents two different interfaces built on top of
>>>> PowerOP -
>>>> cpufreq and sysfs interfaces. So _no_, PowerOP is not all about
>>>
>>> Okay, drop sysfs interface, and we may have something that can be
>>> reviewed.
>>
>> Sysfs is a separate patch that can rejected. Nothing is stopping
>> people from reviewing.
>
> If you submit patch series with one bad patch, you are very unlikely
> to get feedback for the good patches.
>
>>> Actually that's good idea. Submit powerop without doing _any_ kernel
>>> interface changes, so we can see that it makes sense...
>>
>> Just to be clear this is the approach we did and are doing.
>
> That's not what I remember. Please resubmit, then. And cc lkml this
> time.
>
>> btw, if people on this list are not ready to ACK PowerOP, I would like
>> to hear why before we go elsewhere. It looks like all major issues
>> have been addressed by our approach and implementation.
>
> No, I'm not ready to ACK. Actually I'd describe it as "broken piece of
> code noone needs".

But people on this list from TI, Nokia, and Motorola have explained why
its needed. Also, we explained why in the f2f linux-pm summit. Can
you give some concrete reasons why its not needed that have not been
addressed already?

> And IIRC Greg's last question was "what is it good
> for?".

That was a long time ago and again many people from the embedded
community have provided lots of answers.

> Dave Jones was not too pleased with cpufreq/powerop
> integration.

Really?! I don't think he has reviewed our latest integration patches.
Our first submission was a result of discussion with Dominik at the
linux-pm summit. The latest submission is a result of Dave Jones
comments. I think we have addressed all expressed concerns. I can't
force anybody to review this stuff and I'm sure Dave is still catching
up from his vacation.

> Intel people explained you broke centrino
> speedstep.

I didn't see that. Was it off-list? We did not break centrino. In
fact we use both the acpi and hardcoded tables just as cpufreq does.
If its broken, then it was already broken.

> Shall I continue?

Please. Again, I still say we have addressed all expressed
concerns/questions/issues. If you don't feel we have, please give some
concrete statements that you are concerned about or don't understand.
As you can see, many people are happy to help explain.

PowerOP is necessary to build the power management software required
for embedded mobile devices, so we need to reach an understanding. If
the power management guys on this list don't understand PowerOP, then
moving this discussion to lkml isn't going to help. I much prefer to
work together to figure out something than throw it over the wall.

>
> Pavel
> --
> (english) http://www.livejournal.com/~pavelmachek
> (cesky, pictures)
> http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html
>