From mboxrd@z Thu Jan 1 00:00:00 1970 From: Dave Jones Subject: Re: nokia 770 [was Re: community PM requirements/issues and PowerOP] Date: Thu, 14 Dec 2006 08:17:12 -0500 Message-ID: <20061214131712.GC17565@redhat.com> References: <457FEE17.8080806@gmail.com> <20061213210359.GC11843@elf.ucw.cz> <200612131332.58606.david-b@pacbell.net> <20061213215351.GE2418@redhat.com> <5062AF8D-E97F-41D2-8602-59578F2B4655@comcast.net> <20061213225802.GN2418@redhat.com> <458123F5.6090104@gmail.com> <20061214121214.GR2418@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable Return-path: Content-Disposition: inline In-Reply-To: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: linux-pm-bounces@lists.osdl.org Errors-To: linux-pm-bounces@lists.osdl.org To: Vitaly Wool Cc: Pavel Machek , Amit Kucheria , scott.preece@motorola.com, Matthew Locke , linux-pm@lists.osdl.org List-Id: linux-pm@vger.kernel.org On Thu, Dec 14, 2006 at 04:01:58PM +0300, Vitaly Wool wrote: > On 12/14/06, Dave Jones wrote: > > > > > > But what sense does it make for a user,sysadmin or application > > to change voltage? If any of these want to save power, they do so > > by a) doing less work, and then b) lowering the clock speed as this > > is inherently tied to voltage. > > > = > It makes sense to perform changing an operating point dynamically in > userland. An operating point does not have to revolve around the voltage, nor should = it. Fill out the following. * A sysadmin wants to set the CPU voltage to 1.5V because _________________ * A user wants to set the CPU voltage to 1.5V because _________________ * An application wants to dynamically set the voltage rather than the frequency because ______________________ > That said, voltage should be accessible from userland. Try again. It's completely the wrong knob to be turning. Dave -- = http://www.codemonkey.org.uk