[PATCH v3] arm64: dts: renesas: r8a779g3: Update thermal trip points on V4H Sparrow Hawk

[Geert Uytterhoeven]

On Mon, 18 Aug 2025 at 08:48, Geert Uytterhoeven <geert at linux-m68k.org> wrote:
> On Fri, 15 Aug 2025 at 01:35, Marek Vasut
> <marek.vasut+renesas at mailbox.org> wrote:
> > Since the Sparrow Hawk has a smaller PCB than the White Hawk, it tends
> > to generate more heat. To prevent potential damage to the board, adjust
> > the temperature trip points.
> >
> > Add four "passive" trip points which increasingly throttle the CPU to
> > prevent overheating. The first trip point at 68°C disables the 1.8 GHz
> > and 1.7 GHz modes and limits the CPU to 1.5 GHz frequency. The second
> > trip point at 72°C disables the 1.5 GHz mode and limits the CPU to 1.0
> > GHz frequency. The third trip point at 76°C uses thermal-idle to start
> > inserting idle cycles into the CPU instruction stream to cool the CPU
> > cores down. The fourth and last trip point at 80°C disables the 1.0 GHz
> > mode and limits the CPU to 500 MHz frequency.
> >
> > In case the SoC heats up further, in case either of the thermal sensors
> > readings passes the 100°C, a thermal shutdown is triggered to prevent
> > any damage to the hardware.
> >
> > Reviewed-by: Geert Uytterhoeven <geert+renesas at glider.be>
> > Reviewed-by: Niklas Söderlund <niklas.soderlund+renesas at ragnatech.se>
> > Signed-off-by: Marek Vasut <marek.vasut+renesas at mailbox.org>
> > ---
> > Cc: Conor Dooley <conor+dt at kernel.org>
> > Cc: Geert Uytterhoeven <geert+renesas at glider.be>
> > Cc: Krzysztof Kozlowski <krzk+dt at kernel.org>
> > Cc: Magnus Damm <magnus.damm at gmail.com>
> > Cc: "Niklas Söderlund" <niklas.soderlund at ragnatech.se>
> > Cc: Rob Herring <robh at kernel.org>
> > Cc: devicetree at vger.kernel.org
> > Cc: linux-renesas-soc at vger.kernel.org
> > ---
> > V2: Add RB from Niklas
> > V3: - Sort DT nodes
> >     - Update comment on idle states, note the 0..80%
> >     - Add RB from Geert
>
> Thanks, will queue in renesas-devel for v6.18.

With s/r8a779g3: Update thermal trip points on V4H Sparrow
Hawk/sparrow-hawk: Update thermal trip points/.

Gr{oetje,eeting}s,

                        Geert

-- 
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert at 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