Date: Wed, 2 Feb 2005 21:37:58 +0100 From: Bruno Ducrot <ducrot@poupinou.org> To: Nate Lawson <nate@root.org> Cc: Colin Percival <cperciva@freebsd.org> Subject: Re: New cpufreq framework and drivers Message-ID: <20050202203758.GY1145@poupinou.org> In-Reply-To: <42013223.4080704@root.org> References: <41FFB53B.3020907@root.org> <42012739.9080501@freebsd.org> <42013223.4080704@root.org>
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On Wed, Feb 02, 2005 at 12:03:47PM -0800, Nate Lawson wrote: > Colin Percival wrote: > >Nate Lawson wrote: > > > >>Hardware drivers are of two types, absolute > >>and relative. SpeedStep, Powernow, etc. are absolute drivers in that > >>they set the cpu's base frequency. ACPI throttling, Longrun, etc. are > >>relative drivers that reduce the processor's clock to a fraction of > >>its current base (i.e., they have an additive effect.) > > > > > >If my first glance at the patch is correct, this would have my laptop (a > >1.4GHz > >Pentium M) reporting the availability of the frequencies 600MHz, 800MHz, > >etc. > >from enhanced speedstep, along with the frequencies 300MHz, 400MHz, > >500MHz, and > >700MHz obtained via 50% clock throttling. > > That is correct. The code to support relative drivers was removed > before posting to give the basic framework more testing before I commit > it shortly. The relative support will go in soon after that code is > committed. > But longrun is relative though and can scale voltage. (And the point that longrun can control frequency itself is imho irrelevant). -- Bruno Ducrot -- Which is worse: ignorance or apathy? -- Don't know. Don't care.
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