From mboxrd@z Thu Jan 1 00:00:00 1970 From: Thomas Renninger Subject: Re: [PATCH V6 1/3] cpufreq: intel_pstate: configurable algorithm to get target pstate Date: Mon, 14 Dec 2015 16:13:46 +0100 Message-ID: <3489702.fdaYLucDTN@skinner> References: <1449247235-29389-1-git-send-email-philippe.longepe@linux.intel.com> <8633351.YrHIUtRzE5@skinner> <1449768520.3240.250.camel@spandruv-desk3.jf.intel.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7Bit Return-path: Received: from mx2.suse.de ([195.135.220.15]:52002 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751953AbbLNPNs (ORCPT ); Mon, 14 Dec 2015 10:13:48 -0500 In-Reply-To: <1449768520.3240.250.camel@spandruv-desk3.jf.intel.com> Sender: linux-pm-owner@vger.kernel.org List-Id: linux-pm@vger.kernel.org To: Srinivas Pandruvada Cc: Len Brown , Philippe Longepe , linux-pm@vger.kernel.org, rafael.j.wysocki@intel.com, Prarit Bhargava , viresh.kumar@linaro.org On Thursday, December 10, 2015 09:28:40 AM Srinivas Pandruvada wrote: > On Thu, 2015-12-10 at 14:04 +0100, Thomas Renninger wrote: > > On Wednesday, December 09, 2015 12:21:53 PM Srinivas Pandruvada wrote: > > > On Wed, 2015-12-09 at 15:34 +0100, Thomas Renninger wrote: > > > > On Tuesday, December 08, 2015 10:02:23 AM Srinivas Pandruvada wrote: ... > > > The function > > > to get next state can be common. There is no airmont/silvermont name > > > attached to this (get_target_pstate_use_cpu_load or > > > get_target_pstate_use_performance). So the default callback > > > ".get_target_pstate" can be changed based on preference. > > > > > > This is the order I am thinking of in the order of priority high to > > > low : > > > - User policy (either command line or via cpu-freq scaling_governor) > > > - ACPI > > > - Pickup defaults based on CPU ID. That would mean if ACPI pm profile is unknown and only then, assign algorithm (or other tunables) based on CPU ID? > > Why by CPU ID? This doesn't make sense to me and unnecessarily complicates > > things. > > Some CPU are designed for a specific functions. Ok, I nearly bought this... Then I started reading (only a very bit). Silvermont is simply a CPU model. It's not a bound to specific functions like different ARM processors with possibly very specific chipset. It's just a general X86 processor, right? And here: https://en.wikipedia.org/wiki/Silvermont I get: List of Silvermont processors: Desktop processors (Bay Trail-D) Server processors (Avoton) Communications processors (Rangeley) Embedded/automotive processors (Bay Trail-I) Mobile processors (Bay Trail-M) Tablet processors (Bay Trail-T) Smartphone processors (Merrifield and Moorefield) List of Airmont processors Mobile processors (Braswell) Smartphone and Tablet processors (Cherry Trail) Not sure what specific functions you mean... Can you name them? I cut the rest of the mail which was very helpful info and explained quite some open details. Thanks! Thomas