From: "Rafael J. Wysocki" <rjw@rjwysocki.net>
To: "Jon Medhurst (Tixy)" <tixy@linaro.org>
Cc: Viresh Kumar <viresh.kumar@linaro.org>,
Sudeep Holla <sudeep.holla@arm.com>,
linux-pm@vger.kernel.org, linux-kernel@vger.kernel.org,
Michael Turquette <mturquette@baylibre.com>
Subject: Re: [PATCH v2] cpufreq: arm_big_little: fix frequency check when bL switcher is active
Date: Thu, 05 Nov 2015 23:46:21 +0100 [thread overview]
Message-ID: <1780931.75Jjd57heP@vostro.rjw.lan> (raw)
In-Reply-To: <11584056.2Z0CdQiHeS@vostro.rjw.lan>
On Saturday, October 31, 2015 03:34:05 AM Rafael J. Wysocki wrote:
> On Friday, October 30, 2015 10:48:18 AM Jon Medhurst wrote:
> > On Wed, 2015-10-21 at 15:27 +0530, Viresh Kumar wrote:
> > > On 21-10-15, 10:55, Jon Medhurst (Tixy) wrote:
> > > > The check for correct frequency being set in bL_cpufreq_set_rate is
> > > > broken when the big.LITTLE switcher is active, for two reasons.
> > > >
> > > > 1. The 'new_rate' variable gets overwritten before the test by the
> > > > code calculating the frequency of the old cluster.
> > > >
> > > > 2. The frequency returned by bL_cpufreq_get_rate will be the virtual
> > > > frequency, not the actual one the intended version of new_rate contains.
> > > >
> > > > This means the function always returns an error causing an endless
> > > > stream of: "cpufreq: __target_index: Failed to change cpu frequency: -5"
> > > >
> > > > As the intent is to check for errors that clk_set_rate doesn't report
> > > > lets move the check to immediately after that and directly use
> > > > clk_get_rate, rather than the arm_big_little helpers which only confuse
> > > > matters. Also, update the comment to be hopefully clearer about the
> > > > purpose of the code.
> > > >
> > > > Fixes: 0a95e630b49a ("cpufreq: arm_big_little: check if the frequency is set correctly")
> > > >
> > > > Signed-off-by: Jon Medhurst <tixy@linaro.org>
> > > > Acked-by: Sudeep Holla <sudeep.holla@arm.com>
> > > > ---
> > > >
> > [...]
> > >
> > > Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
> > >
> >
> > Do I need to send this again with that Ack and Michael's Reviewed-by
> > added?
>
> Nope, it's on my to-do list.
Applied now, thanks!
Rafael
next prev parent reply other threads:[~2015-11-05 22:17 UTC|newest]
Thread overview: 6+ messages / expand[flat|nested] mbox.gz Atom feed top
2015-10-21 9:55 Jon Medhurst (Tixy)
2015-10-21 9:57 ` Viresh Kumar
2015-10-30 10:48 ` Jon Medhurst (Tixy)
2015-10-31 2:34 ` Rafael J. Wysocki
2015-11-05 22:46 ` Rafael J. Wysocki [this message]
2015-10-26 12:42 ` Michael Turquette
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=1780931.75Jjd57heP@vostro.rjw.lan \
--to=rjw@rjwysocki.net \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-pm@vger.kernel.org \
--cc=mturquette@baylibre.com \
--cc=sudeep.holla@arm.com \
--cc=tixy@linaro.org \
--cc=viresh.kumar@linaro.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
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
all inboxes | Powered by JetHome®