Re: [PATCH v8 04/16] clk: npcm8xx: add clock controller

From: Stephen Boyd <sboyd@kernel.org>
To: Tomer Maimon <tmaimon77@gmail.com>
Cc: "Arnd Bergmann" <arnd@arndb.de>,
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Subject: Re: [PATCH v8 04/16] clk: npcm8xx: add clock controller
Date: Thu, 04 Aug 2022 13:05:47 -0700	[thread overview]
Message-ID: <20220804200549.60512C433C1@smtp.kernel.org> (raw)
In-Reply-To: <CAP6Zq1hOxG+2X-qTbvPkrVHQ5zf04GO21m1n328Jiqgzns2CMA@mail.gmail.com>

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 situation.
> 

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?