Re: [PATCH 11/13] clk: renesas: rzg2l-cpg: drop determine_rate op and use CLK_ROUNDING_FW_MANAGED flag

From: Brian Masney

Date: Fri Feb 27 2026 - 11:07:36 EST


On Fri, Feb 27, 2026 at 03:57:28PM +0000, Biju Das wrote:
> > -----Original Message-----
> > From: Brian Masney <bmasney@xxxxxxxxxx>
> > Sent: 27 February 2026 15:48
> > Subject: Re: [PATCH 11/13] clk: renesas: rzg2l-cpg: drop determine_rate op and use
> > CLK_ROUNDING_FW_MANAGED flag
> >
> > Hi Biju,
> >
> > On Fri, Feb 27, 2026 at 03:23:19PM +0000, Biju Das wrote:
> > > > -----Original Message-----
> > > > From: Geert Uytterhoeven <geert@xxxxxxxxxxxxxx>
> > > > Sent: 27 February 2026 15:09
> > > > Subject: Re: [PATCH 11/13] clk: renesas: rzg2l-cpg: drop
> > > > determine_rate op and use CLK_ROUNDING_FW_MANAGED flag
> > > >
> > > > On Fri, 27 Feb 2026 at 16:01, Brian Masney <bmasney@xxxxxxxxxx> wrote:
> > > > > On Fri, Feb 27, 2026 at 09:20:09AM +0100, Geert Uytterhoeven wrote:
> > > > > > On Thu, 26 Feb 2026 at 19:18, Brian Masney <bmasney@xxxxxxxxxx> wrote:
> > > > > > > This clk driver has a noop determine_rate clk op. Drop this
> > > > > > > empty function, and enable the CLK_ROUNDING_FW_MANAGED flag.
> > > > > > >
> > > > > > > Signed-off-by: Brian Masney <bmasney@xxxxxxxxxx>
> > > > > >
> > > > > > Thanks for your patch!
> > > > > >
> > > > > > > --- a/drivers/clk/renesas/rzg2l-cpg.c
> > > > > > > +++ b/drivers/clk/renesas/rzg2l-cpg.c
> > > >
> > > > > > > @@ -1041,7 +1034,7 @@ rzg2l_cpg_sipll5_register(const struct cpg_core_clk *core,
> > > > > > > init.name = core->name;
> > > > > > > parent_name = __clk_get_name(parent);
> > > > > > > init.ops = &rzg2l_cpg_sipll5_ops;
> > > > > > > - init.flags = 0;
> > > > > > > + init.flags = CLK_ROUNDING_FW_MANAGED;
> > > > > >
> > > > > > Iff this is the Right Thing To Do (TM), it needs a comment, as
> > > > > > this clock is not managed by firmware.
> > > > >
> > > > > Before I start a larger discussion on patch 1 with more people
> > > > > about a name for this flag, help me understand why this provider
> > > > > has a noop determine rate. Is the hardware eventually programmed
> > > > > with a rate that's close enough to what was passed in? Or it
> > > > > doesn't really matter what the clock rate is, just as long as it
> > > > > is running? Or should the determine_rate function be filled out in this particular case?
> > > >
> > > > I'd like to defer to Biju, who added the empty round^Wdetermine rate function.
> > >
> > > PLL is capable of generating any frequency. that is the reason.
> > >
> > > But we could, call rzg2l_cpg_get_foutpostdiv_rate() from
> > > determine_rate() as modified rzg2l_cpg_get_foutpostdiv_rate()[1] can
> > > return errors
> > >
> > > [1]
> > > https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git/tr
> > > ee/drivers/clk/renesas/rzg2l-cpg.c?h=next-20260227#n590
> >
> > OK. So how do you all want to proceed here?
> >
> > Do you want to fill out the determine rate in this driver? If so, we can just drop this particular
> > patch from this series.
>
> We plan to fill out the determine rate later, as it can return error.

OK, if you are planning to fill out the determine rate, then I'll just
skip over this driver to avoid the code churn.

Brian