From: Andy Shevchenko <andy.shevchenko@gmail.com>
To: Liu Ying <victor.liu@nxp.com>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>,
Heiko Stuebner <heiko@sntech.de>,
Elaine Zhang <zhangqing@rock-chips.com>,
Stephen Boyd <sboyd@kernel.org>,
linux-kernel@vger.kernel.org, linux-clk@vger.kernel.org,
linux-arm-kernel@lists.infradead.org,
linux-rockchip@lists.infradead.org,
Michael Turquette <mturquette@baylibre.com>,
NXP Linux Team <linux-imx@nxp.com>, Jacky Bai <ping.bai@nxp.com>
Subject: Re: [PATCH v2 2/3] clk: fractional-divider: Introduce NO_PRESCALER flag
Date: Thu, 22 Jul 2021 12:38:15 +0300 [thread overview]
Message-ID: <CAHp75Vdm8nO-zT0vyKcB1hOXkR7_2RY-2P_fnkjV5BCc+uoqXQ@mail.gmail.com> (raw)
In-Reply-To: <9117e5212a3b743ca541918ec2b701c159ac752c.camel@nxp.com>
On Thu, Jul 22, 2021 at 12:33 PM Liu Ying <victor.liu@nxp.com> wrote:
> On Fri, 2021-07-16 at 16:34 +0300, Andy Shevchenko wrote:
> > The newly introduced flag, when set, makes the flow to skip
> > the assumption that the caller will use an additional 2^scale
> > prescaler to get the desired clock rate.
>
> As I mentioned in v1 comment, it seems to be good to decouple the
> prescaler knowledge from this common fractional divider clk driver.
> This way, we'll make it simpler and easier to maintain. Also, then, the
> NO_PRESCALER flag is not needed at all. However, it seems that two
> Intel drivers which use the frational divider drivers will be affected
> and rate negotiation logics need to be implemented for them. Please
> consider if it's doable or not.
The current driver works for the certain hardware without this change.
If you think it's better, submit a proposal we will discuss.
> If we ultimately keep the prescaler knowledge here, please consider to
> add the NO_PRESCALER flag for i.MX7ulp as it hasn't the prescaler IIUC.
You mean there is a code which is currently using this driver w/o
taking into account this prescaller flavour? Can you, please, point
out, I'll definitely update it. Thanks for the catch!
--
With Best Regards,
Andy Shevchenko
next prev parent reply other threads:[~2021-07-22 9:39 UTC|newest]
Thread overview: 8+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-07-16 13:34 [PATCH v2 1/3] clk: fractional-divider: Export approximation algo to the CCF users Andy Shevchenko
2021-07-16 13:34 ` [PATCH v2 2/3] clk: fractional-divider: Introduce NO_PRESCALER flag Andy Shevchenko
2021-07-22 9:29 ` Liu Ying
2021-07-22 9:38 ` Andy Shevchenko [this message]
2021-07-22 9:43 ` Liu Ying
2021-07-22 15:42 ` Andy Shevchenko
2021-07-16 13:34 ` [PATCH v2 3/3] clk: fractional-divider: Document the arithmetics used behind the code Andy Shevchenko
2021-07-17 12:19 ` [PATCH v2 1/3] clk: fractional-divider: Export approximation algo to the CCF users Heiko Stübner
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=CAHp75Vdm8nO-zT0vyKcB1hOXkR7_2RY-2P_fnkjV5BCc+uoqXQ@mail.gmail.com \
--to=andy.shevchenko@gmail.com \
--cc=andriy.shevchenko@linux.intel.com \
--cc=heiko@sntech.de \
--cc=linux-arm-kernel@lists.infradead.org \
--cc=linux-clk@vger.kernel.org \
--cc=linux-imx@nxp.com \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-rockchip@lists.infradead.org \
--cc=mturquette@baylibre.com \
--cc=ping.bai@nxp.com \
--cc=sboyd@kernel.org \
--cc=victor.liu@nxp.com \
--cc=zhangqing@rock-chips.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).