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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:   Wed, 29 Mar 2023 10:52:01 -0700
User-Agent: alot/0.10
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Quoting Jacky Huang (2023-03-28 23:02:31)
>=20
> On 2023/3/29 =E4=B8=8A=E5=8D=88 11:54, Stephen Boyd wrote:
> > Quoting Jacky Huang (2023-03-28 20:43:23)
> >
> >> We just employ regmap mechansim for the access to REG_SYS_RLKTZNS regi=
ster.
> >> Is this implementation OK for you?=C2=A0 Thank you.
> >>
> > No. Why can't that be a hwspinlock? Or why can't it be unlocked all the
> > time and rely on software spinlocks in the kernel to prevent concurrent
> > access to the registers accessed by a driver, like a lock for the clk
> > registers and a lock for the reset registers, etc. Or if no two clks or
> > resets exist within one 32-bit word then no lock is necessary.
>=20
> You gave a good suggestion here. Yes, of course we can let it be=20
> unlocked all the time.
> We can unlock the "register lock" before entering Linux.
> As a result, the unlonk and lock register related code is not required.
> Thus, we can remove syscon from the clock controller node.
>=20
> If you agree with this, we will modify it in the next version.
>=20

Sure, that works.