RE: [PATCH 2/7] clk: renesas: r8a77965: Add DAB clock

[Fabrizio Castro]

Hi Geert,


Thanks for your feedback!

> From: Geert Uytterhoeven <geert@xxxxxxxxxxxxxx>
> Sent: 26 February 2021 08:45
> Subject: Re: [PATCH 2/7] clk: renesas: r8a77965: Add DAB clock
> 
> Hi Fabrizio,
> 
> On Thu, Feb 25, 2021 at 11:53 PM Fabrizio Castro
> <fabrizio.castro.jz@xxxxxxxxxxx> wrote:
> > This patch adds the DAB clock to the R8A77965 SoC.
> >
> > Signed-off-by: Fabrizio Castro <fabrizio.castro.jz@xxxxxxxxxxx>
> 
> Thanks for your patch!
> 
> > --- a/drivers/clk/renesas/r8a77965-cpg-mssr.c
> > +++ b/drivers/clk/renesas/r8a77965-cpg-mssr.c
> > @@ -250,6 +250,7 @@ static const struct mssr_mod_clk r8a77965_mod_clks[]
> __initconst = {
> >         DEF_MOD("ssi2",                 1013,   MOD_CLK_ID(1005)),
> >         DEF_MOD("ssi1",                 1014,   MOD_CLK_ID(1005)),
> >         DEF_MOD("ssi0",                 1015,   MOD_CLK_ID(1005)),
> > +       DEF_MOD("dab",                  1016,   R8A77965_CLK_S0D6),
> 
> Unfortunately this bit is not documented in the R-Car Gen3 Hardware
> User's Manual, so I have to trust you on this.
> 
> While it's not unusual that the same module on R-Car E3 and M3-N
> has different parent clocks, it does strike me as odd that S0D6 on M3-N
> runs at 133 MHz, while S3D1 on E3 runs at 266 MHz.
> Probably it doesn't matter that much, as your driver doesn't care
> about the actual clock rate.

I had the same concerns but we have received confirmation for this.
Hopefully an official document will be released soon.

Thanks,
Fab

> 
> >         DEF_MOD("scu-all",              1017,   R8A77965_CLK_S3D4),
> >         DEF_MOD("scu-dvc1",             1018,   MOD_CLK_ID(1017)),
> >         DEF_MOD("scu-dvc0",             1019,   MOD_CLK_ID(1017)),
> 
> Gr{oetje,eeting}s,
> 
>                         Geert
> 
> 
> --
> Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@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