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Subject: Re: [PATCH v6 08/12] arm64: dts: nuvoton: Add initial ma35d1 device tree
From:   Stephen Boyd <sboyd@kernel.org>
Cc:     devicetree@vger.kernel.org, linux-clk@vger.kernel.org,
        linux-kernel@vger.kernel.org, linux-serial@vger.kernel.org,
        arnd@arndb.de, schung@nuvoton.com, mjchen@nuvoton.com,
        Jacky Huang <ychuang3@nuvoton.com>
To:     Jacky Huang <ychuang570808@gmail.com>, gregkh@linuxfoundation.org,
        jirislaby@kernel.org, krzysztof.kozlowski+dt@linaro.org,
        lee@kernel.org, mturquette@baylibre.com, p.zabel@pengutronix.de,
        robh+dt@kernel.org
Date:   Tue, 28 Mar 2023 19:46:10 -0700
User-Agent: alot/0.10
Precedence: bulk

Quoting Jacky Huang (2023-03-28 19:39:36)
> On 2023/3/29 =E4=B8=8A=E5=8D=88 10:19, Stephen Boyd wrote:
> > What do you use the syscon for then? The clock driver must want to use
> > the syscon for something, implying that they are the same device.
>=20
> The register lock mechanism is applied to protect many critical=20
> registers from false written.
> The register lock control register is one register in system controller.
> Some registers of the clock controller are lock protected. Not only=20
> clock controller, but other
> IP such as RTC, PWM, ADC, etc, also have lock protected registers. All=20
> these IP requires
> syscon to access the lock/unlock control register in the system controlle=
r.
> That's why we add a <&sys> to the clock controller.
>=20
> Should we implement a ma35d1-sysctl driver to protect register_lock()=20
> and register_unlock()
> and export to those drivers?=C2=A0 If yes, we can remove the <&sys> from =

> clock controller.
>=20

You can implement the lock and unlock in the hwspinlock framework. See
drivers/hwspinlock.