From: Peter De Schrijver <pdeschrijver@nvidia.com>
To: Bill Huang <bilhuang@nvidia.com>
Cc: Stephen Warren <swarren@wwwdotorg.org>,
"mturquette@linaro.org" <mturquette@linaro.org>,
"patches@linaro.org" <patches@linaro.org>,
"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
Russell King - ARM Linux <linux@arm.linux.org.uk>,
"linaro-dev@lists.linaro.org" <linaro-dev@lists.linaro.org>,
"linux-arm-kernel@lists.infradead.org"
<linux-arm-kernel@lists.infradead.org>
Subject: Re: [RFC 1/1] clk: Add notifier support in clk_prepare_enable/clk_disable_unprepare
Date: Thu, 14 Mar 2013 11:21:32 +0200 [thread overview]
Message-ID: <20130314092132.GE18519@tbergstrom-lnx.Nvidia.com> (raw)
In-Reply-To: <1363227311.3311.30.camel@bilhuang-vm1>
On Thu, Mar 14, 2013 at 03:15:11AM +0100, Bill Huang wrote:
> I don't think deferring will work either, considering the usage of DVFS,
> device voltage is tightly coupled with frequency, when clock rate is
> about to increase, we have to boost voltage first and we can lower the
> voltage after the clock rate has decreased. All the above sequence have
> to be guaranteed or you might crash, so deferring not only make thing
> complicated in controlling the order but also hurt performance.
But we could use notifiers in clk_prepare/clk_unprepare to set the voltage no?
As clk_prepare/clk_unprepare have to be called before clk_enable or after
clk_disable, the voltage can be raised to a safe level, before the clock
becomes active.
Cheers,
Peter.
next prev parent reply other threads:[~2013-03-14 9:21 UTC|newest]
Thread overview: 30+ messages / expand[flat|nested] mbox.gz Atom feed top
2013-03-12 12:37 Bill Huang
2013-03-12 13:40 ` Russell King - ARM Linux
2013-03-13 1:47 ` Bill Huang
2013-03-13 4:42 ` Stephen Warren
2013-03-13 5:08 ` Bill Huang
2013-03-13 5:24 ` Stephen Warren
2013-03-13 5:40 ` Bill Huang
2013-03-13 18:10 ` Stephen Warren
2013-03-14 2:15 ` Bill Huang
2013-03-14 9:21 ` Peter De Schrijver [this message]
2013-03-14 9:28 ` Bill Huang
2013-03-14 17:54 ` Stephen Warren
2013-03-15 1:20 ` Bill Huang
2013-03-15 5:22 ` Stephen Warren
2013-03-15 5:48 ` Bill Huang
2013-03-15 9:39 ` Peter De Schrijver
2013-03-15 10:08 ` Ulf Hansson
2013-03-15 12:06 ` Bill Huang
2013-03-15 12:33 ` Ulf Hansson
2013-03-15 19:38 ` Stephen Warren
2013-03-16 1:54 ` Bill Huang
2013-03-18 10:36 ` Ulf Hansson
2013-03-21 22:28 ` Mike Turquette
2013-03-16 2:23 ` Bill Huang
2013-03-15 17:12 ` Russell King - ARM Linux
2013-03-15 17:09 ` Russell King - ARM Linux
2013-03-16 2:25 ` Bill Huang
2013-03-15 16:59 ` Russell King - ARM Linux
2013-03-15 16:57 ` Russell King - ARM Linux
2013-03-15 18:44 ` Nicolas Pitre
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=20130314092132.GE18519@tbergstrom-lnx.Nvidia.com \
--to=pdeschrijver@nvidia.com \
--cc=bilhuang@nvidia.com \
--cc=linaro-dev@lists.linaro.org \
--cc=linux-arm-kernel@lists.infradead.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux@arm.linux.org.uk \
--cc=mturquette@linaro.org \
--cc=patches@linaro.org \
--cc=swarren@wwwdotorg.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®