Linux Power Management development
 help / color / mirror / Atom feed
From: Sudeep Holla <sudeep.holla@arm.com>
To: Ram Chandrasekar <rkumbako@codeaurora.org>
Cc: Amit Kucheria <amit.kucheria@linaro.org>,
	devicetree@vger.kernel.org, Sudeep Holla <sudeep.holla@arm.com>,
	ilina@codeaurora.org, Zhang Rui <rui.zhang@intel.com>,
	Eduardo Valentin <edubezval@gmail.com>,
	Rob Herring <robh+dt@kernel.org>,
	Mark Rutland <mark.rutland@arm.com>,
	linux-pm@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH] thermal: of: Allow selection of thermal governor in DT
Date: Tue, 6 Mar 2018 12:32:08 +0000	[thread overview]
Message-ID: <6d5aeab8-aafe-fa3b-585e-953a34864e7d@arm.com> (raw)
In-Reply-To: <3b80853abb45a9e067cf7a16754b07bb67712457.1520274879.git.amit.kucheria@linaro.org>



On 05/03/18 18:36, Amit Kucheria wrote:
> From: Ram Chandrasekar <rkumbako@codeaurora.org>
> 
> There is currently no way for the governor to be selected for each thermal
> zone in devicetree. 

How is that any different from cpufreq, cpuidle or devfreq subsystems ?

> This results in the default governor being used for all
> thermal zones even though no such restriction exists in the core code.
> 

What restrictions ?

> Add support for specifying the thermal governor to be used for a thermal
> zone in the devicetree.

Then what prevents us from doing the same for other subsystems with so
called /inefficient default/ governors ?

> The devicetree config should specify the governor
> name as a string that matches any available governors. If not specified, we
> maintain the current behaviour of using the default governor.

If one is specified, can the user change it from sysfs ? If
yes, then why do we need this binding at all ? If no, we are basically
restricting, then what would happen if the DT was shipped with wrong
governor specified because the firmware author didn't know about any
other governor ?

IMO, having this in DT is bad idea as it may cause more issues than
gain. We already have sysfs support like other PM subsystems and
userspace can deal with it.

-- 
Regards,
Sudeep

  parent reply	other threads:[~2018-03-06 12:32 UTC|newest]

Thread overview: 12+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
     [not found] <cover.1520274879.git.amit.kucheria@linaro.org>
2018-03-05 18:36 ` [PATCH] thermal: of: Allow selection of thermal governor in DT Amit Kucheria
2018-03-05 20:08   ` Rob Herring
2018-03-06  5:38     ` Amit Kucheria
2018-03-05 21:11   ` Daniel Lezcano
2018-03-06  5:48     ` Amit Kucheria
2018-03-06 15:43       ` Daniel Lezcano
2018-03-06 12:32   ` Sudeep Holla [this message]
2018-03-07 10:59     ` Amit Kucheria
2018-03-08  4:49       ` Viresh Kumar
2018-03-08  5:35         ` Amit Kucheria
2018-03-08  5:42           ` Viresh Kumar
2018-03-08 12:41       ` Sudeep Holla

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=6d5aeab8-aafe-fa3b-585e-953a34864e7d@arm.com \
    --to=sudeep.holla@arm.com \
    --cc=amit.kucheria@linaro.org \
    --cc=devicetree@vger.kernel.org \
    --cc=edubezval@gmail.com \
    --cc=ilina@codeaurora.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-pm@vger.kernel.org \
    --cc=mark.rutland@arm.com \
    --cc=rkumbako@codeaurora.org \
    --cc=robh+dt@kernel.org \
    --cc=rui.zhang@intel.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