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=-2.9 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS,USER_AGENT_NEOMUTT autolearn=unavailable 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 582CBC43613 for ; Mon, 24 Jun 2019 09:43:54 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 2D06F208CA for ; Mon, 24 Jun 2019 09:43:54 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=linaro.org header.i=@linaro.org header.b="SQ/ngd4m" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728366AbfFXJnw (ORCPT ); Mon, 24 Jun 2019 05:43:52 -0400 Received: from mail-pf1-f195.google.com ([209.85.210.195]:34422 "EHLO mail-pf1-f195.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726481AbfFXJnw (ORCPT ); Mon, 24 Jun 2019 05:43:52 -0400 Received: by mail-pf1-f195.google.com with SMTP id c85so7205806pfc.1 for ; Mon, 24 Jun 2019 02:43:52 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to:user-agent; bh=dV+hpYbGfRGXFvtF+Lfe9yalvB//tMvrxl/pRmYwcng=; b=SQ/ngd4msMUIPRv2c/dYdDsed9ND7ilayDReo1/ls41mTFqemaMtbzZKrBfYs/B78t uA6r6vhUR5aKBJK1fPTYE9NiZcr0v+FlmWBDLD8tnyryBjZr3kZzGwJx/yQTqFez94s3 ryKPQk3139Y84cKLunqaFt+JZj7TiF4m375GAoiKaAa1iB7CiZQZUWb3qykhXQ2nTo1I lNhZaCcqGIUPSMUQ28qA+ltUtaECfZrFQ3ENnRxeS+Pg3kWSf4LylEWZuo8GxVuIZwid wxiJW2bOwj6Bsps7aelMFiTej5mPtpYVm0l+ss/D/ORIFSk3mwW16IiFMwGuEv69IAPA uSOQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to:user-agent; bh=dV+hpYbGfRGXFvtF+Lfe9yalvB//tMvrxl/pRmYwcng=; b=XOXarF4CFKaJI5vVNDbKCuMvdV+Y03h8+8sWu7mwn9B/yIsQQxEnSlQWM2q3U1VtND aL6wR+QjG+Va3zGiGkneO2g8exbKxoA43l+pdk+6l4aw+Q8YVmYssnrE0nhWI22PbtFs 0bYpM7I8pBQVxAfFbltMV9TRuZ+FUcbgmx4Uagk+GvAoTon1FP2ncfLbYfAdKm5m090i NdxeH4Uw2roCtdAZViADq1VJTPb2IQHuDQhDTr/lEMwQT/Zpp1M6xQyoqO/LYbHR2bMC fCXQGMsTOGxN+p+zn+1DM05/PsIGhhLzuaxe9WpkGdEY4iE3IR406KuFhmjXDLsi1rvh rAeQ== X-Gm-Message-State: APjAAAW957P52gj06kCF0ATIzLXSnkJMQdLcvk2itDs8Xoqtuwrmk6Cn qULrQnnRKiou8e+zd+N6vppK0A== X-Google-Smtp-Source: APXvYqz7ncTVXqaPWF0r1zHZNr+xEaLdLJzuLNFtO9pSi9dtOl/Fd7SnoidmNIDaiGT5xtHnyGkt5w== X-Received: by 2002:a17:90a:fa07:: with SMTP id cm7mr23936237pjb.115.1561369431698; Mon, 24 Jun 2019 02:43:51 -0700 (PDT) Received: from localhost ([122.172.211.128]) by smtp.gmail.com with ESMTPSA id x8sm10417055pfa.46.2019.06.24.02.43.50 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Mon, 24 Jun 2019 02:43:51 -0700 (PDT) Date: Mon, 24 Jun 2019 15:13:49 +0530 From: Viresh Kumar To: Saravana Kannan Cc: MyungJoo Ham , Kyungmin Park , Chanwoo Choi , Viresh Kumar , Nishanth Menon , Stephen Boyd , "Rafael J. Wysocki" , kernel-team@android.com, linux-pm@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH v1 0/3] Add required-opps support to devfreq passive gov Message-ID: <20190624094349.rtjb7nuv6g7zmsf2@vireshk-i7> References: <20190622003449.33707-1-saravanak@google.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20190622003449.33707-1-saravanak@google.com> User-Agent: NeoMutt/20180716-391-311a52 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 21-06-19, 17:34, Saravana Kannan wrote: > The devfreq passive governor scales the frequency of a "child" device > based on the current frequency of a "parent" device (not parent/child in > the sense of device hierarchy). As of today, the passive governor > requires one of the following to work correctly: > 1. The parent and child device have the same number of frequencies > 2. The child device driver passes a mapping function to translate from > parent frequency to child frequency. > > When (1) is not true, (2) is the only option right now. But often times, > all that is required is a simple mapping from parent's frequency to > child's frequency. > > Since OPPs already support pointing to other "required-opps", add > support for using that to map from parent device frequency to child > device frequency. That way, every child device driver doesn't have to > implement a separate mapping function anytime (1) isn't true. Can you please provide a real world example with DT code here so I can understand it better ? -- viresh