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=-5.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS autolearn=no 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 22708C433ED for ; Fri, 14 May 2021 22:12:37 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 0232561440 for ; Fri, 14 May 2021 22:12:36 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231516AbhENWNr (ORCPT ); Fri, 14 May 2021 18:13:47 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:43370 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230111AbhENWNr (ORCPT ); Fri, 14 May 2021 18:13:47 -0400 Received: from mail-io1-xd36.google.com (mail-io1-xd36.google.com [IPv6:2607:f8b0:4864:20::d36]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id AD7A6C06174A for ; Fri, 14 May 2021 15:12:35 -0700 (PDT) Received: by mail-io1-xd36.google.com with SMTP id t11so264022iol.9 for ; Fri, 14 May 2021 15:12:35 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=telus.net; s=google; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=dZMndnk0T1uTjKIdZ8gA20TvCc8i9uHipdNCN8I7bSE=; b=VUmg4Ex+eKEwF5VKUcH/ujoG6JcjCuJ0zGB5+OIXqcHbLmCt0eCgACXtirFrtF8W41 qbKpF/7sXH0hzK6mjMTeISJ6NNh57jahyLXdAUpM8MLM2I4W44QYA5kWXJcC39l4tL3X v1Bk3CLdvdFCcjWgVVN+hvnmSj2qBfdAz/hxZF01gXF5JMrVKx10WuWWACY05i6YiGT9 vFA61sAQeWOOSn+18nhmNiKQF2eLf0F2x7WvrdSpvuls4rT0CymJdC8+ST/+aRCv7Uwx xVr5kafehUxaVZpIT09Mf61JV5VuPG4hDNKQO2+QuW+Tqrx7lU8wga6s/jGB4GdekPde 10Gg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=dZMndnk0T1uTjKIdZ8gA20TvCc8i9uHipdNCN8I7bSE=; b=ZcrT92J/2ARqhdVO8F1/2k4yBtmdHOvZzQ0WHeFVzgX8gYH+qGWB48znRwlr74+8Qx D9VH6J1MSdUEQiKJHUkwVMQfiT7IdePIJk3WQom5h/dEGLF9JFvSOulU/4LEDZkSIguo wApNyRXhEua7RH+5oRSBLIbqbL275wqgiUyVsOnAyp6dFfJ9b9JYYmDD0xCbO5hv+zZf RS+5zxTtVsvo1naFixmVde7fBw5M8IBT+lT7u9B7nCNk38KHD4RzW3ET3MLoltA0HRWU tGLKcDnd+Slu8f8mLSD+5mMixBYCrBZzBbEEqJpnOjW5a4tv6p+WGR+dwkrROoghAfrz RF9w== X-Gm-Message-State: AOAM532BPh7ILaTkKLZWWA3QFzlGNYRW27cK240Xp/ZYtnbYZ2kTZCCB guiOLPQ0VPB0xarQtMyQZVH0eoWAWUTvWhf3tliMjLPoNKomsVZ/ X-Google-Smtp-Source: ABdhPJxG4E9bc+8tnH9GPoUVS4PvC6gplyn4zWhN22jL6nWcJLIGUclw2CUF55y9tIEhlYc8yzN0dE55zeN0hmGvCqQ= X-Received: by 2002:a05:6602:204f:: with SMTP id z15mr15400564iod.99.1621030355132; Fri, 14 May 2021 15:12:35 -0700 (PDT) MIME-Version: 1.0 References: <20210513132051.31465-1-ggherdovich@suse.cz> <067ee60e47a0350d01f0c3f216c1032818044b36.camel@suse.cz> In-Reply-To: <067ee60e47a0350d01f0c3f216c1032818044b36.camel@suse.cz> From: Doug Smythies Date: Fri, 14 May 2021 15:12:25 -0700 Message-ID: Subject: Re: [PATCH v2] cpufreq: intel_pstate: Add Icelake servers support in no-HWP mode To: Giovanni Gherdovich Cc: "Rafael J . Wysocki" , Viresh Kumar , Srinivas Pandruvada , Len Brown , Linux PM list , Linux Kernel Mailing List , dsmythies Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-pm@vger.kernel.org On Fri, May 14, 2021 at 1:33 PM Giovanni Gherdovich wrote: > On Fri, 2021-05-14 at 08:31 -0700, Doug Smythies wrote: > > > Can I on-board to this patch or do you want me to submit another? > > I want to add COMETLAKE (tested), as below: > > > > ... Doug > > Hello Doug! Hi Giovanni, Thank you for your reply. > > Wait, why you don't want to use HWP? It's such a fantastic technology! > > :) I'm just teasing you. > > More seriously: > > when COMETLAKE is not in that list, can you confirm that if you go into the > BIOS config at boot, and disable HWP from there, then intel_pstate does *not* load? Yes, already tested before my original reply. > Does it say "intel_pstate: CPU model not supported" in the dmesg log? That I did not check, but if I boot now with an unmodified kernel 5.13-rc1 (i.e. without this patch): [ 0.369323] intel_pstate: CPU model not supported > The control may be somewhere around "power mangement" in the BIOS config, and > may be called "Enable/disable Intel Speed Shift". Yes. > I'm asking because I've just checked on two Dell laptops, one Skylake and the > other Kabylake, and the menu is there in the BIOS config to disable HWP, > but if I disable it... nothing happens. "lscpu" shows all the hwp flags as usual: Motherboard here is ASUS PRIME Z490-A. CPU: Intel(R) Core(TM) i5-10600K CPU @ 4.10GHz > # lscpu | grep Flags | tr ' ' '\n' | grep hwp > hwp > hwp_notify > hwp_act_window > hwp_epp Here, for some reason I have to do it this way (sudo) or your command doesn't work properly. Results herein confirmed by looking at the "Flags" output manually without filtering: intel_speed_shift = Disabled in BIOS: doug@s19:~$ sudo lscpu | tr ' ' '\n' | grep hwp doug@s19:~$ intel_speed_shift = Auto in BIOS $ sudo lscpu | tr ' ' '\n' | grep hwp hwp hwp_notify hwp_act_window hwp_epp > and turbostat gives me: > > # turbostat -Summary -i 1 : 2>&1 | grep MSR_PM_ENABLE > cpu0: MSR_PM_ENABLE: 0x00000001 (HWP) Here: intel_speed_shift = Disabled in BIOS: root@s19:/home/doug# /home/doug/temp-k-git/linux/tools/power/x86/turbostat/turbostat -Summary -i 1 : 2>&1 | grep MSR_PM_ENABLE root@s19:/home/doug# intel_speed_shift = Auto in BIOS (the default setting) root@s19:/home/doug# /home/doug/temp-k-git/linux/tools/power/x86/turbostat/turbostat -Summary -i 1 : 2>&1 | grep MSR_PM_ENABLE cpu0: MSR_PM_ENABLE: 0x00000001 (HWP) or with "intel_pstate=no_hwp" root@s19:/home/doug# /home/doug/temp-k-git/linux/tools/power/x86/turbostat/turbostat -Summary -i 1 : 2>&1 | grep MSR_PM_ENABLE cpu0: MSR_PM_ENABLE: 0x00000000 (No-HWP) > Which is to say, on the Intel client machines I have, the firmware doesn't > seem to be able to hide HWP from the OS. Buggy BIOS? Maybe, the fact of the > matter is, I wouldn't need to add, say, KABYLAKE to that list, based on my > experience. My experience (hardware) differs from yours with respect to this. > The other side of the issue is that, from my understanding, the > preferred/supported way to disable HWP is to boot with intel_pstate=no_hwp, > and that list is a sort of "known exceptions" that people really can't live > without (it's mostly server CPUs, and mostly because of unfortunate firmware > defaults). Otherwise you'd see the entire intel-family.h file in there. I'm not sure how to respond here. Yes, I'd expect to see a big list here, and in the recently added TCC Offset thermal stuff and in the recently added turbostat patches to deal with a TCC offset. I do not understand doing things partially only. But that is a bigger/broader subject than herein. That said, yes, "intel_pstate=no_hwp" is what I normally do. And my BIOS normally has "Intel Speed Shift = AUTO", which is the default. ... deleted the rest ... ... Doug