[PATCH v3 2/2] drm: rcar-du: calculate DPLLCR to be more small jitter

Geert Uytterhoeven geert at linux-m68k.org
Fri Dec 15 08:36:03 UTC 2017


Hi Morimoto-san,

On Fri, Dec 15, 2017 at 9:12 AM, Kuninori Morimoto
<kuninori.morimoto.gx at renesas.com> wrote:
>> > From: Kuninori Morimoto <kuninori.morimoto.gx at renesas.com>
>> > In general, PLL has VCO (= Voltage controlled oscillator),
>> > one of the very important electronic feature called as "jitter"
>> > is related to this VCO.
>> > In academic generalism, VCO should be maximum to be more small jitter.
>> > In high frequency clock, jitter will be large impact.
>> > Thus, selecting Hi VCO is general theory.
>>
>> Thanks for your patch!
>>
>> > One note here is that it should be 2000 < fvco < 4096MHz
>>
>> 2000 Hz? (else it could be misinterpreted that MHz applies to both values).
>
> Laurent had asked same question ;)
> But, yes, it is 2000 Hz

I've seen his question, that's why I think you should make it unambiguous.

Gr{oetje,eeting}s,

                        Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert at linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds


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