From: nicolas.ferre@atmel.com (Nicolas Ferre)
To: linux-arm-kernel@lists.infradead.org
Subject: [PATCH v2] Add cpuidle support for at91
Date: Wed, 30 Sep 2009 14:56:34 +0200 [thread overview]
Message-ID: <4AC35582.8000404@atmel.com> (raw)
In-Reply-To: <20090930123449.GB3238@laptop>
Albin Tonnerre :
>> Just one precision: what is the difference, entering state0 with only
>> the current cpu_do_idle() that is activated by default ?
>
> Sorry, I don't get what you mean. Would you mind elaborating a bit?
I guess that during idle time, even without the cpuidle infrastructure,
the SOC enters arch_idle() that calls cpu_do_idle().
So, now that I have your patch applied, I wonder what is the difference
between the old situation and the first state of the cpuidle table.
In other words, only state "wait-for-interrupt *and* RAM self refresh"
brings some more power saving. Indeed, cpu_do_idle() that correspond to
the "WFI" state was already the way of dealing with idle cpu, even
without your patch. Am I correct ?
Best regards,
--
Nicolas Ferre
next prev parent reply other threads:[~2009-09-30 12:56 UTC|newest]
Thread overview: 6+ messages / expand[flat|nested] mbox.gz Atom feed top
[not found] <1247680190-19674-1-git-send-email-albin.tonnerre@free-electrons.com>
[not found] ` <200908111200.58866.marc.pignat@hevs.ch>
[not found] ` <20090812165700.GC4051@pc-ras4041.res.insa>
[not found] ` <200908130858.47487.marc.pignat@hevs.ch>
[not found] ` <20090813193241.GA5985@pc-ras4041.res.insa>
[not found] ` <20090909151417.GA4014@pc-ras4041.res.insa>
2009-09-29 14:15 ` [PATCH v2] Add cpuidle support for at91 Nicolas Ferre
2009-09-30 12:34 ` Albin Tonnerre
2009-09-30 12:56 ` Nicolas Ferre [this message]
2009-10-02 8:46 ` Wolfram Sang
2009-10-09 10:53 ` Albin Tonnerre
2009-10-22 15:47 ` Albin Tonnerre
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=4AC35582.8000404@atmel.com \
--to=nicolas.ferre@atmel.com \
--cc=linux-arm-kernel@lists.infradead.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;
as well as URLs for NNTP newsgroup(s).