Re: [PATCH v4 7/7] RFC: drm/panfrost: devfreq: Add support for 2 regulators

[Nicolas Boichat]

On Thu, Feb 13, 2020 at 3:57 PM Nicolas Boichat <drinkcat@xxxxxxxxxxxx> wrote:
> > > [snip]
> > > But then there's a slight problem: panfrost_devfreq uses a bunch of
> > > clk_get_rate calls, and the clock PLLs (at least on MTK platform) are
> > > never fully precise, so we get back 299999955 for 300 Mhz and
> > > 799999878 for 800 Mhz. That means that the kernel is unable to keep
> > > devfreq stats as neither of these values are in the table:
> > > [ 4802.470952] devfreq devfreq1: Couldn't update frequency transition
> > > information.
> > > The kbase driver fixes this by remembering the last set frequency, and
> > > reporting that to devfreq. Should we do that as well or is there a
> > > better fix?

This one is my bad, I was missing this patch in my forklift to 4.19:
22bd4df9dadf46f drm/panfrost: devfreq: Round frequencies to OPPs

(should really try to boot that board on linux-next, but that's for
another time)