Linux-ARM-MSM Archive on lore.kernel.org
 help / color / Atom feed
From: Stephen Boyd <sboyd@kernel.org>
To: Michael Turquette <mturquette@baylibre.com>,
	Taniya Das <tdas@codeaurora.org>
Cc: Andy Gross <andy.gross@linaro.org>,
	David Brown <david.brown@linaro.org>,
	Rajendra Nayak <rnayak@codeaurora.org>,
	linux-arm-msm@vger.kernel.org, linux-soc@vger.kernel.org,
	linux-clk@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH v1 2/3] clk: qcom: rcg2: Add support for hardware control mode
Date: Tue, 16 Jul 2019 16:18:44 -0700
Message-ID: <20190716231845.832F82064B@mail.kernel.org> (raw)
In-Reply-To: <916e2fb3-98b9-c4e3-50e0-3581a41609d6@codeaurora.org>

Quoting Taniya Das (2019-07-15 21:19:02)
> Hello Stephen,
> 
> Thanks for your review.
> 
> On 7/16/2019 4:22 AM, Stephen Boyd wrote:
> > Quoting Taniya Das (2019-05-08 11:24:54)
> >> diff --git a/drivers/clk/qcom/clk-rcg2.c b/drivers/clk/qcom/clk-rcg2.c
> >> index 57dbac9..5bb6d45 100644
> >> --- a/drivers/clk/qcom/clk-rcg2.c
> >> +++ b/drivers/clk/qcom/clk-rcg2.c
> >> @@ -289,6 +289,9 @@ static int __clk_rcg2_configure(struct clk_rcg2 *rcg, const struct freq_tbl *f)
> >>          cfg |= rcg->parent_map[index].cfg << CFG_SRC_SEL_SHIFT;
> >>          if (rcg->mnd_width && f->n && (f->m != f->n))
> >>                  cfg |= CFG_MODE_DUAL_EDGE;
> >> +       if (rcg->flags & HW_CLK_CTRL_MODE)
> >> +               cfg |= CFG_HW_CLK_CTRL_MASK;
> >> +
> > 
> > Above this we have commit bdc3bbdd40ba ("clk: qcom: Clear hardware clock
> > control bit of RCG") that clears this bit. Is it possible to always set
> > this bit and then have an override flag used in sdm845 that says to
> > _not_ set this bit? Presumably on earlier platforms writing the bit is a
> > no-op so it's safe to write the bit on those platforms.
> > 
> > This way, if it's going to be the default we can avoid setting the flag
> > and only set the flag on older platforms where it shouldn't be done for
> > some reason.
> > 
> 
> Not all the subsystem clock controllers might have this hardware control
> bit set from design. Thus we want to set them based on the flag.

Yes but what's the percentage of clks that are going to set this flag
vs. not set this flag? If that is low right now then it's fine but if it
eventually becomes the standard mechanism it will be easier to opt-out
of the feature if necessary instead of opt-in.


  reply index

Thread overview: 19+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2019-05-08 18:24 [PATCH v1 0/3] clk: qcom: Misc updates for Root Clock Generators Taniya Das
2019-05-08 18:24 ` [PATCH v1 1/3] clk: qcom: rcg: Return failure for RCG update Taniya Das
2019-07-15 22:52   ` Stephen Boyd
2019-05-08 18:24 ` [PATCH v1 2/3] clk: qcom: rcg2: Add support for hardware control mode Taniya Das
2019-07-15 22:52   ` Stephen Boyd
2019-07-16  4:19     ` Taniya Das
2019-07-16 23:18       ` Stephen Boyd [this message]
2019-07-30 10:50         ` Taniya Das
2019-07-30 15:38           ` Stephen Boyd
2019-05-08 18:24 ` [PATCH v1 3/3] clk: qcom: rcg: update the DFS macro for RCG Taniya Das
2019-05-09 17:27   ` Stephen Boyd
2019-05-10  2:58     ` Taniya Das
2019-05-10 17:54       ` Stephen Boyd
2019-05-13  3:44         ` Taniya Das
2019-07-15 22:44           ` Stephen Boyd
2019-07-16  4:22             ` Taniya Das
2019-07-16 23:22               ` Stephen Boyd
2019-07-30 10:51                 ` Taniya Das
2019-07-30 15:40                   ` Stephen Boyd

Reply instructions:

You may reply publically 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=20190716231845.832F82064B@mail.kernel.org \
    --to=sboyd@kernel.org \
    --cc=andy.gross@linaro.org \
    --cc=david.brown@linaro.org \
    --cc=linux-arm-msm@vger.kernel.org \
    --cc=linux-clk@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-soc@vger.kernel.org \
    --cc=mturquette@baylibre.com \
    --cc=rnayak@codeaurora.org \
    --cc=tdas@codeaurora.org \
    /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

Linux-ARM-MSM Archive on lore.kernel.org

Archives are clonable:
	git clone --mirror https://lore.kernel.org/linux-arm-msm/0 linux-arm-msm/git/0.git

	# If you have public-inbox 1.1+ installed, you may
	# initialize and index your mirror using the following commands:
	public-inbox-init -V2 linux-arm-msm linux-arm-msm/ https://lore.kernel.org/linux-arm-msm \
		linux-arm-msm@vger.kernel.org
	public-inbox-index linux-arm-msm

Example config snippet for mirrors

Newsgroup available over NNTP:
	nntp://nntp.lore.kernel.org/org.kernel.vger.linux-arm-msm


AGPL code for this site: git clone https://public-inbox.org/public-inbox.git