Hi Prabhakar,
On Tue, 2 Sept 2025 at 17:06, Lad, Prabhakar <prabhakar.csengg@xxxxxxxxx> wrote:
> On Tue, Sep 2, 2025 at 2:01 PM Geert Uytterhoeven <geert@xxxxxxxxxxxxxx> wrote:
> > On Mon, 1 Sept 2025 at 20:30, Prabhakar <prabhakar.csengg@xxxxxxxxx> wrote:
> > > From: Lad Prabhakar <prabhakar.mahadev-lad.rj@xxxxxxxxxxxxxx>
> > >
> > > Add module and core clocks used by Ethernet Subsystem (Ethernet_SS),
> > > Ethernet MAC (GMAC), Ethernet Switch (ETHSW).
> > >
> > > Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@xxxxxxxxxxxxxx>
> >
> > > --- a/drivers/clk/renesas/r9a09g077-cpg.c
> > > +++ b/drivers/clk/renesas/r9a09g077-cpg.c
> > > @@ -181,7 +191,12 @@ static const struct mssr_mod_clk r9a09g077_mod_clks[] __initconst = {
> > > DEF_MOD("sci4fck", 12, CLK_SCI4ASYNC),
> > > DEF_MOD("iic0", 100, R9A09G077_CLK_PCLKL),
> > > DEF_MOD("iic1", 101, R9A09G077_CLK_PCLKL),
> > > + DEF_MOD("gmac0", 400, R9A09G077_CLK_PCLKM),
> > > + DEF_MOD("ethsw", 401, R9A09G077_CLK_PCLKM),
> >
> > According to Table 7.13 ("Overview of Clock Generation Circuit
> > Specifications (Internal Clock)"), ETCLKA is used as the operating
> > clock for ETHSW?
> >
> There are 3 clock inputs to ETHSW,
> - PCLKM - bus clock
> - ETCLKA - operating clock
> - ETCLKB - Ts clock
>
> Based on Documentation/devicetree/bindings/net/dsa/renesas,rzn1-a5psw.yaml
> we have two clocks for RZ/N1 (Ts clock is missing)
> - description: AHB clock used for the switch register interface
> - description: Switch system clock
>
> - const: hclk
> - const: clk
>
> So I was treating,
> - hclk -> PCLKM,
> - clk -> ETCLKA
> - ts -> ETCLKB
>
> Since pclkm is used for register access, I added this entry to the
> r9a09g077_mod_clks array as I was under the impression the clocks used
> for reg access need to go into this array.
OK, thanks for the explanation!
Gr{oetje,eeting}s,
Geert
--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@xxxxxxxxxxxxxx
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
