Re: [PATCH v4 09/13] net: ethernet: ti: cpts: rework initialization/deinitialization

From: Richard Cochran
Date: Tue Dec 06 2016 - 13:04:33 EST


On Tue, Dec 06, 2016 at 11:49:14AM -0600, Grygorii Strashko wrote:
> But we do reset whole cpsw :( and that's required to support PM use cases as
> suspend/resume.

The code is resetting the clock unconditionally on ifup/down. That
sucks. If you reset the clock *only* after resume, that would be ok.

> There are also PM requirement to shutdown cpsw in case all interfaces are down.

Well, those requirements are not too smart. As an end user, I expect
that ifdown/up does not change the time. There isn't any reason to
reset the clock in this case.

> More over, there are requirement to minimize cpsw power consumption in case all links are
> disconnected (and cpts is special case here).
>
> So, at least resetting of the timecounter still required.

Only if you follow that poorly conceived PM plan. Anyhow, I agree
that it isn't the task of your present series to fix that.

> Ok. I'll try to optimize it following your directions.

What I would like to see is: initialize the cyclecounter fields
exactly once.

Thanks,
Richard