From: Herve Codina <herve.codina@bootlin.com>
To: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Wolfram Sang <wsa+renesas@sang-engineering.com>,
Magnus Damm <magnus.damm@gmail.com>,
Rob Herring <robh@kernel.org>,
Krzysztof Kozlowski <krzk+dt@kernel.org>,
Conor Dooley <conor+dt@kernel.org>,
linux-renesas-soc@vger.kernel.org, devicetree@vger.kernel.org,
linux-kernel@vger.kernel.org,
Pascal Eberhard <pascal.eberhard@se.com>,
Miquel Raynal <miquel.raynal@bootlin.com>,
Thomas Petazzoni <thomas.petazzoni@bootlin.com>
Subject: Re: [PATCH v2] ARM: dts: renesas: r9a06g032: Add support for CPU frequency scaling
Date: Mon, 2 Mar 2026 18:23:35 +0100 [thread overview]
Message-ID: <20260302182335.312e0c3a@bootlin.com> (raw)
In-Reply-To: <CAMuHMdUi+FsBveQ9HU+NT7iE7QOX0tKn4Jt_1mfDdq_D0=czJA@mail.gmail.com>
On Mon, 2 Mar 2026 18:04:36 +0100
Geert Uytterhoeven <geert@linux-m68k.org> wrote:
> Hi Hervé,
>
> On Thu, 15 Jan 2026 at 17:49, Herve Codina (Schneider Electric)
> <herve.codina@bootlin.com> wrote:
> > In RZ/N1 SoCs, CPUs are allowed to work at 125, 250 or 500 MHz when the
> > 'ref' clock frequency value is set to 500 MHz which is the default 'ref'
> > clock frequency value.
> >
> > Add support for CPU frequency scaling defining those 3 frequencies in
> > the opp-table with the assumption that the 'ref' clock is set to its
> > default value.
> >
> > Signed-off-by: Herve Codina (Schneider Electric) <herve.codina@bootlin.com>
>
> Thanks for your patch, which LGTM.
>
> > --- a/arch/arm/boot/dts/renesas/r9a06g032.dtsi
> > +++ b/arch/arm/boot/dts/renesas/r9a06g032.dtsi
>
> > @@ -24,6 +57,7 @@ cpu@0 {
> > compatible = "arm,cortex-a7";
> > reg = <0>;
> > clocks = <&sysctrl R9A06G032_CLK_A7MP>;
> > + operating-points-v2 = <&cpu_opp_table>;
> > };
> >
> > cpu@1 {
>
> Unless I am missing something, the RZ/N1 clock driver does not support
> the A7MP clock yet, so how can cpufreq work for you?
R9A06G032_CLK_A7MP is DIV_CA7
https://elixir.bootlin.com/linux/v6.19.3/source/include/dt-bindings/clock/r9a06g032-sysctrl.h#L78
https://elixir.bootlin.com/linux/v6.19.3/source/drivers/clk/renesas/r9a06g032-clocks.c#L261
https://elixir.bootlin.com/linux/v6.19.3/source/drivers/clk/renesas/r9a06g032-clocks.c#L455
And on my system, got the following:
# cat /sys/devices/system/cpu/cpufreq/policy0/stats/time_in_state
125000 4574
250000 108
500000 392
#
All defined opp-hz values seems to be used without any errors. I hope that
any errors would be reported in kernel logs. At least this one:
https://elixir.bootlin.com/linux/v6.19.3/source/drivers/cpufreq/cpufreq.c#L2329
Best regards,
Hervé
next prev parent reply other threads:[~2026-03-02 17:23 UTC|newest]
Thread overview: 4+ messages / expand[flat|nested] mbox.gz Atom feed top
2026-01-15 16:49 [PATCH v2] ARM: dts: renesas: r9a06g032: Add support for CPU frequency scaling Herve Codina (Schneider Electric)
2026-03-02 17:04 ` Geert Uytterhoeven
2026-03-02 17:23 ` Herve Codina [this message]
2026-03-03 7:54 ` Geert Uytterhoeven
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20260302182335.312e0c3a@bootlin.com \
--to=herve.codina@bootlin.com \
--cc=conor+dt@kernel.org \
--cc=devicetree@vger.kernel.org \
--cc=geert@linux-m68k.org \
--cc=krzk+dt@kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-renesas-soc@vger.kernel.org \
--cc=magnus.damm@gmail.com \
--cc=miquel.raynal@bootlin.com \
--cc=pascal.eberhard@se.com \
--cc=robh@kernel.org \
--cc=thomas.petazzoni@bootlin.com \
--cc=wsa+renesas@sang-engineering.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox