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Subject: Re: [PATCH v8 04/16] clk: npcm8xx: add clock controller
From:   Stephen Boyd <sboyd@kernel.org>
Cc:     Arnd Bergmann <arnd@arndb.de>,
        Avi Fishman <avifishman70@gmail.com>,
        Benjamin Fair <benjaminfair@google.com>,
        Biju Das <biju.das.jz@bp.renesas.com>,
        Bjorn Andersson <bjorn.andersson@linaro.org>,
        Catalin Marinas <catalin.marinas@arm.com>,
        Daniel Lezcano <daniel.lezcano@linaro.org>,
        Geert Uytterhoeven <geert+renesas@glider.be>,
        Greg KH <gregkh@linuxfoundation.org>,
        Jonathan =?utf-8?q?Neusch=C3=A4fer?= <j.neuschaefer@gmx.net>,
        Jiri Slaby <jirislaby@kernel.org>,
        Joel Stanley <joel@jms.id.au>,
        Krzysztof Kozlowski <krzysztof.kozlowski+dt@linaro.org>,
        Guenter Roeck <linux@roeck-us.net>,
        Lubomir Rintel <lkundrak@v3.sk>,
        Marcel Ziswiler <marcel.ziswiler@toradex.com>,
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To:     Tomer Maimon <tmaimon77@gmail.com>
Date:   Thu, 04 Aug 2022 13:05:47 -0700
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Quoting Tomer Maimon (2022-08-04 07:01:30)
> On Sat, 30 Jul 2022 at 01:56, Stephen Boyd <sboyd@kernel.org> wrote:
> >
> > Because it is jumbled in some range?
> Yes.
> >
> > >
> > > I do see a way to combine the clock and the reset driver, the NPCM
> > > reset driver is serving other NPCM BMC's.
> > > Should we use regmap to handle the clock registers instead of ioremap?
> >
> > Sure? Using regmap or not looks like a parallel discussion. How does it
> > help use platform APIs?
> I mean to use regmap API instead of platform API for handing the clock
> and reset registers.
> the regmap API gives only one user access to R/W (lock).
> I will be happy to get more suggestions, on how should we solve this situ=
ation.
>=20

Using platform APIs means using platform_*() functions, not of_*()
functions, which are open-firmware/DT related. Regmap can be used to
operate on registers mapped as __iomem, which is different from platform
APIs.

Is having a lock even necessary? Do the reset and clk controls live
within a shared register where we would need to prevent one driver from
accessing that register at the same time as the other?