From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-0.9 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id B6F7FC65BAF for ; Wed, 12 Dec 2018 21:40:26 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 82E9620839 for ; Wed, 12 Dec 2018 21:40:26 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 82E9620839 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=molgen.mpg.de Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727622AbeLLVkZ (ORCPT ); Wed, 12 Dec 2018 16:40:25 -0500 Received: from mx3.molgen.mpg.de ([141.14.17.11]:50931 "EHLO mx1.molgen.mpg.de" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1726263AbeLLVkZ (ORCPT ); Wed, 12 Dec 2018 16:40:25 -0500 Received: from [192.168.0.3] (ip5f5bd26f.dynamic.kabel-deutschland.de [95.91.210.111]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) (Authenticated sender: pmenzel) by mx.molgen.mpg.de (Postfix) with ESMTPSA id DA1D9201353427; Wed, 12 Dec 2018 22:40:22 +0100 (CET) To: Srinivas Pandruvada , Len Brown Cc: linux-pm@vger.kernel.org, LKML From: Paul Menzel Subject: intel_pstate: Lowest frequency not reached with Intel i7-6700 Message-ID: Date: Wed, 12 Dec 2018 22:40:22 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.2.1 MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: de-DE Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Dear Linux folks, Using *powersave* as P-state selection algorithm, on an idle system with an Intel i7-6700 (Sandy Bridge), the frequency only goes down to 900 MHz instead of the minimum frequency of 800 MHz. > $ uname -a > Linux keineahnung.molgen.mpg.de 4.20.0-rc5.mx64.234 #1 SMP Mon Dec 3 16:58:29 CET 2018 x86_64 GNU/Linux > $ dmesg | grep state > [ 0.000000] x86/fpu: xstate_offset[2]: 576, xstate_sizes[2]: 256 > [ 0.000000] x86/fpu: xstate_offset[3]: 832, xstate_sizes[3]: 64 > [ 0.000000] x86/fpu: xstate_offset[4]: 896, xstate_sizes[4]: 64 > [ 0.000000] x86/fpu: Enabled xstate features 0x1f, context size is 960 bytes, using 'compacted' format. > [ 0.686027] acpi PNP0C0B:00: Failed to change power state to D0 > [ 0.694017] acpi PNP0C0B:00: Failed to set initial power state > [ 0.703020] acpi PNP0C0B:01: Failed to change power state to D0 > [ 0.712012] acpi PNP0C0B:01: Failed to set initial power state > [ 0.722010] acpi PNP0C0B:02: Failed to change power state to D0 > [ 0.730013] acpi PNP0C0B:02: Failed to set initial power state > [ 0.739010] acpi PNP0C0B:03: Failed to change power state to D0 > [ 0.748012] acpi PNP0C0B:03: Failed to set initial power state > [ 0.758009] acpi PNP0C0B:04: Failed to change power state to D0 > [ 0.766012] acpi PNP0C0B:04: Failed to set initial power state > [ 0.767127] Monitor-Mwait will be used to enter C-1 state > [ 0.767131] Monitor-Mwait will be used to enter C-2 state > [ 0.767134] Monitor-Mwait will be used to enter C-3 state > [ 2.092456] intel_pstate: Intel P-state driver initializing > [ 2.094820] intel_pstate: HWP enabled > $ lscpu > Architecture: x86_64 > CPU op-mode(s): 32-bit, 64-bit > Byte Order: Little Endian > CPU(s): 8 > On-line CPU(s) list: 0-7 > Thread(s) per core: 2 > Core(s) per socket: 4 > Socket(s): 1 > NUMA node(s): 1 > Vendor ID: GenuineIntel > CPU family: 6 > Model: 94 > Model name: Intel(R) Core(TM) i7-6700 CPU @ 3.40GHz > Stepping: 3 > CPU MHz: 900.392 > CPU max MHz: 4000.0000 > CPU min MHz: 800.0000 > BogoMIPS: 6816.00 > Virtualization: VT-x > L1d cache: 32K > L1i cache: 32K > L2 cache: 256K > L3 cache: 8192K > NUMA node0 CPU(s): 0-7 > Flags: fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm pbe syscall nx pdpe1gb rdtscp lm constant_tsc art arch_perfmon pebs bts rep_good nopl xtopology nonstop_tsc cpuid aperfmperf tsc_known_freq pni pclmulqdq dtes64 monitor ds_cpl vmx smx est tm2 ssse3 sdbg fma cx16 xtpr pdcm pcid sse4_1 sse4_2 x2apic movbe popcnt aes xsave avx f16c rdrand lahf_lm abm 3dnowprefetch cpuid_fault epb invpcid_single pti tpr_shadow vnmi flexpriority ept vpid ept_ad fsgsbase tsc_adjust bmi1 hle avx2 smep bmi2 erms invpcid rtm mpx rdseed adx smap clflushopt intel_pt xsaveopt xsavec xgetbv1 xsaves dtherm ida arat pln pts hwp hwp_notify hwp_act_window hwp_epp > $ cat /sys/devices/system/cpu/cpufreq/policy*/scaling_governor > powersave > powersave > powersave > powersave > powersave > powersave > powersave > powersave > $ cat /sys/devices/system/cpu/cpufreq/policy*/scaling_cur_freq > 900335 > 900285 > 900179 > 900314 > 900510 > 900226 > 900376 > 900375 Shouldn’t it go down until 800 MHz? Kind regards, Paul