Re: [PATCH V2] drm/panel: boe-tv101wum-nl6: Fine tune Himax83102-j02 panel HFP and HBP

From: Doug Anderson
Date: Mon Nov 20 2023 - 13:05:07 EST


Hi,

On Sun, Nov 19, 2023 at 5:33 PM cong yang
<yangcong5@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxx> wrote:
>
> Hi,
>
> On Sat, Nov 18, 2023 at 1:11 AM Doug Anderson <dianders@xxxxxxxxxxxx> wrote:
> >
> > Hi,
> >
> > On Thu, Nov 16, 2023 at 7:25 PM Cong Yang
> > <yangcong5@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxx> wrote:
> > >
> > > The refresh reported by modetest is 60.46Hz, and the actual measurement
> > > is 60.01Hz, which is outside the expected tolerance.
> >
> > Presumably you've swapped the numbers above? The value reported by
> > modetest is 60.01Hz and the actual measurement is 60.46Hz?
>
> No, the value reported by modetest is 60.46Hz.

Indeed. I somehow assumed that the old value of "clock / (htotal *
vtotal)" would have been the one that was closer to 60 Hz, but doing
the math I agree with you. Specifically:

>>> 161600000 / ((1200 + 40 + 20 + 40) * (1920 + 116 + 8 + 12))
60.46093983837174

>>> 162850000 / ((1200 + 50 + 20 + 50) * (1920 + 116 + 8 + 12))
60.005453366348306

Thanks for correcting me!

-Doug