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

From: Fabrizio Castro
Date: Wed Mar 03 2021 - 09:51:22 EST


Hi Geert,

> From: Fabrizio Castro <fabrizio.castro.jz@xxxxxxxxxxx>
> Sent: 01 March 2021 15:01
> Subject: RE: [PATCH 2/7] clk: renesas: r8a77965: Add DAB clock
>
> Hi Laurent,
>
> Thanks for your feedback!
>
> > From: Laurent Pinchart <laurent.pinchart@xxxxxxxxxxxxxxxx>
> > Sent: 26 February 2021 12:49
> > Subject: Re: [PATCH 2/7] clk: renesas: r8a77965: Add DAB clock
> >
> > Hi Fabrizio,
> >
> > Thank you for the patch.
> >
> > On Fri, Feb 26, 2021 at 09:45:20AM +0100, Geert Uytterhoeven wrote:
> > > On Thu, Feb 25, 2021 at 11:53 PM Fabrizio Castro 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 have the exact same concerns, here and for 1/7.
>
> I hear you, but you know how these sort of things go, a bit was left
> behind, now they are aware of this bit missing from the documentation
> and at some point they will release a document addressing this particular
> point. Meanwhile, we have received written confirmation for this, so
> it should be okay.

I think this patch is worth taking.

Thanks,
Fab


>
> 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)),
> >
> > --
> > Regards,
> >
> > Laurent Pinchart