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 79EFAC4361B for ; Mon, 7 Dec 2020 22:31:59 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 3E6682399C for ; Mon, 7 Dec 2020 22:31:59 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727750AbgLGWbn (ORCPT ); Mon, 7 Dec 2020 17:31:43 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:59138 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726120AbgLGWbn (ORCPT ); Mon, 7 Dec 2020 17:31:43 -0500 Received: from mail.skyhub.de (mail.skyhub.de [IPv6:2a01:4f8:190:11c2::b:1457]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id F09A4C061793; Mon, 7 Dec 2020 14:31:02 -0800 (PST) Received: from zn.tnic (p200300ec2f0a3800f6520bb83eb81f06.dip0.t-ipconnect.de [IPv6:2003:ec:2f0a:3800:f652:bb8:3eb8:1f06]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.skyhub.de (SuperMail on ZX Spectrum 128k) with ESMTPSA id 632601EC0391; Mon, 7 Dec 2020 23:31:01 +0100 (CET) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=alien8.de; s=dkim; t=1607380261; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:in-reply-to:in-reply-to: references:references; bh=1pXP7Us+7n31k5o5RoCjT5roVSbCsK8S24nd3SAu6nM=; b=LX+vDVL0KwxEYHMvTNniRiIcWMWirj755BhWqUH6/TdDOrWciishdcFtbOZupUuoNjvEWF gZukmB/j2luqiJEaLk2wDHzvQ2dNrRWwHguZMjIIPyokBmBCkU4qJv1ohgyP4vrmGeF27a mGov61wUvrcTqIn/AhrUl4WTOqlf7UQ= Date: Mon, 7 Dec 2020 23:30:57 +0100 From: Borislav Petkov To: Wei Huang Cc: Punit Agrawal , rjw@rjwysocki.net, wei.huang2@amd.com, linux-kernel@vger.kernel.org, linux-pm@vger.kernel.org, x86@kernel.org Subject: Re: [RFC PATCH 2/4] cpufreq: acpi-cpufreq: Add processor to the ignore PSD override list Message-ID: <20201207223057.GJ20489@zn.tnic> References: <20201125144847.3920-1-punitagrawal@gmail.com> <20201125144847.3920-3-punitagrawal@gmail.com> <20201207202610.GG20489@zn.tnic> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Dec 07, 2020 at 04:07:52PM -0600, Wei Huang wrote: > I think we shouldn't override zen2 if _PSD is correct. In my opinion, > there are two approaches: > > * Keep override_acpi_psd() > Let us keep the original quirk and override_acpi_psd() function. Over > the time, people may want to add new CPUs to override_acpi_psd(). The > maintainer may declare that only CPUs >= family 17h will be fixed, to > avoid exploding the check-list. > > * Remove the quirk completely > We can completely remove commit acd316248205 ("acpi-cpufreq: Add quirk > to disable _PSD usage on all AMD CPUs")? I am not sure what "AMD desktop > boards" was referring to in the original commit message of acd316248205. > Maybe such machines aren't in use anymore. * Third option: do not do anything. Why? - Let sleeping dogs lie and leave the workaround acd316248205 for old machines. - Make a clear cut that the override is not needed from Zen3 on, i.e., your patch 5368512abe08 ("acpi-cpufreq: Honor _PSD table setting on new AMD CPUs") Punit's commit message reads "...indicates that the override is not required for Zen3 onwards, it seems that domain information can be trusted even on certain earlier systems." That's not nearly a justification in my book to do this on anything < Zen3. This way you have a clear cut, you don't need to deal with adding any more models to override_acpi_psd() and all is good. Unless there's a better reason to skip the override on machines < Zen3 but I haven't heard any so far... Thx. -- Regards/Gruss, Boris. https://people.kernel.org/tglx/notes-about-netiquette