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=-2.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 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 812F3C2BA83 for ; Thu, 13 Feb 2020 15:22:18 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 63C2E24699 for ; Thu, 13 Feb 2020 15:22:18 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727529AbgBMPWP (ORCPT ); Thu, 13 Feb 2020 10:22:15 -0500 Received: from foss.arm.com ([217.140.110.172]:47730 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726937AbgBMPWO (ORCPT ); Thu, 13 Feb 2020 10:22:14 -0500 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 663CD328; Thu, 13 Feb 2020 07:22:14 -0800 (PST) Received: from [10.1.195.59] (ifrit.cambridge.arm.com [10.1.195.59]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 5FE623F68E; Thu, 13 Feb 2020 07:22:12 -0800 (PST) Subject: Re: [PATCH v3 5/7] cpufreq: add function to get the hardware max frequency To: Ionela Voinescu Cc: catalin.marinas@arm.com, will@kernel.org, mark.rutland@arm.com, maz@kernel.org, suzuki.poulose@arm.com, sudeep.holla@arm.com, lukasz.luba@arm.com, rjw@rjwysocki.net, peterz@infradead.org, mingo@redhat.com, vincent.guittot@linaro.org, viresh.kumar@linaro.org, linux-arm-kernel@lists.infradead.org, linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, linux-pm@vger.kernel.org References: <20200211184542.29585-1-ionela.voinescu@arm.com> <20200211184542.29585-6-ionela.voinescu@arm.com> <20200213125918.GA2397@arm.com> From: Valentin Schneider Message-ID: Date: Thu, 13 Feb 2020 15:22:11 +0000 User-Agent: Mozilla/5.0 (X11; Linux aarch64; rv:68.0) Gecko/20100101 Thunderbird/68.4.1 MIME-Version: 1.0 In-Reply-To: <20200213125918.GA2397@arm.com> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: linux-pm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pm@vger.kernel.org On 2/13/20 12:59 PM, Ionela Voinescu wrote: >> What about intel_pstate / turbo stuff? IIRC one of Giovanni's issues was that >> turbo freq is not always reported as the max freq. Dunno if we can do >> anything about it; at the very least maybe document the caveat? >> > > Okay, I can add details in the description in regards to potential > reasons to overwrite this function. But basically this is one of the > reasons for making this a weak function. The best information we can > generically get for maximum hardware frequency is cpuinfo.max_freq. > But if platforms have the possibility to obtain this differently from > either hardware or firmware they can overwrite this. > Right, that would be handled by a different implementation of that function, so this wasn't too relevant of a comment. Sorry!