From patchwork Wed Jul 17 22:23:35 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Saravana Kannan X-Patchwork-Id: 11048275 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id E90A66C5 for ; Wed, 17 Jul 2019 22:23:53 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id C8E7E212BE for ; Wed, 17 Jul 2019 22:23:53 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id B965F2877F; Wed, 17 Jul 2019 22:23:53 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-15.5 required=2.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,MAILING_LIST_MULTI,RCVD_IN_DNSWL_HI, USER_IN_DEF_DKIM_WL autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 77621212BE for ; Wed, 17 Jul 2019 22:23:52 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727606AbfGQWXv (ORCPT ); Wed, 17 Jul 2019 18:23:51 -0400 Received: from mail-qk1-f202.google.com ([209.85.222.202]:39600 "EHLO mail-qk1-f202.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727468AbfGQWXv (ORCPT ); Wed, 17 Jul 2019 18:23:51 -0400 Received: by mail-qk1-f202.google.com with SMTP id x1so21424763qkn.6 for ; Wed, 17 Jul 2019 15:23:50 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=date:message-id:mime-version:subject:from:to:cc; bh=39fzf43hDflkP+uYiNQxS6xaHQ083/QpMzmuyzPtUdY=; b=wFgStKALBEnEGt6LhTq/NEkpkuHrszbthkXReAklwB+fSi7678pDRTqdNzz1J4M7nQ ithAPBOwnlK/vKTUQ8NpZ2t9LBCBbrrJe3mw3JT0Dgfce1x2Q5MuyZtMXeSoOexQFeQV py46WEEyAGWvUX+KNIp/iqwcV0fa/fzpvLiC/4OQTxkpTvI5wRI9EHAYAtfoEDifD/GT /iNk5d/5wuI4iQBwCsijLBHpImT7oD4vEh2hK7wDETFJTR/pmnq0CBWdMndIj669gqKJ fuL9MWGkllNLV1YHMI9IXiPM9Fd8XTzkdEguRkLxJ8n+cyxQfOhUUrLsYskJyMXGyHJ6 wFcA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:message-id:mime-version:subject:from:to:cc; bh=39fzf43hDflkP+uYiNQxS6xaHQ083/QpMzmuyzPtUdY=; b=i2vEn+iBO1deOrfKS7meGZep/b+02II9bL2kjnwyZABDpUVpq9T7TlXF7mw5Iwf1ny igkwjHO1foR/4mBMXHOUIBgGkCa9lqOy+Fy4WvxTkZDRjkkNtV++IrMnSlKl/V/NkXIF Wy78EgNtsS47yqEHWDbOLWkmOhw/wvBQpIczdN9cl1ZVdLrN1t9wXWpHXd/sZXRVTtvz z9P+wAvK/nIiEMGnpk9qs1BmqRL3h4+gTEjgTgORU6pF4TWAed/lmoFm/IG/dINo55i7 6HVB2ej7Y2wk+/V7gD9ZBp9xe4ZxJ0jGFg6+FBvfXVrDrdL7cMZUzTn8mLzc3Ipc+zJV eVIQ== X-Gm-Message-State: APjAAAWOmtRGM4KL07A+g8TKmAEWqKT1K651cEsLHjoF8dX0IcCaTtwc s+2ENfl/cFvH4C4F/sZhN5P+7a6/yCw1Neg= X-Google-Smtp-Source: APXvYqwwmRW+eTEOj6donm+FHv+AKebXI1S/kdC9w7+cgDZiZMcYPmje/plxm0cMIQaq2SjBbLWVGj32MbX3BsU= X-Received: by 2002:a37:646:: with SMTP id 67mr26866101qkg.287.1563402229934; Wed, 17 Jul 2019 15:23:49 -0700 (PDT) Date: Wed, 17 Jul 2019 15:23:35 -0700 Message-Id: <20190717222340.137578-1-saravanak@google.com> Mime-Version: 1.0 X-Mailer: git-send-email 2.22.0.510.g264f2c817a-goog Subject: [PATCH v3 0/5] Add required-opps support to devfreq passive gov From: Saravana Kannan To: MyungJoo Ham , Kyungmin Park , Chanwoo Choi , Viresh Kumar , Nishanth Menon , Stephen Boyd , "Rafael J. Wysocki" Cc: Saravana Kannan , Sibi Sankar , kernel-team@android.com, linux-pm@vger.kernel.org, linux-kernel@vger.kernel.org Sender: linux-pm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pm@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP 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. Some common (but not comprehensive) reason for needing a devfreq passive governor to adjust the frequency of one device based on another are: 1. These were the combination of frequencies that were validated/screened during the manufacturing process. 2. These are the sensible performance combinations between two devices interacting with each other. So that when one runs fast the other doesn't become the bottleneck. 3. Hardware bugs requiring some kind of frequency ratio between devices. For example, the following mapping can't be captured in DT as it stands today because the parent and child device have different number of OPPs. But with this patch series, this mapping can be captured cleanly. In arch/arm64/boot/dts/exynos/exynos5433-bus.dtsi you have something like this with the following changes: bus_g2d_400: bus0 { compatible = "samsung,exynos-bus"; clocks = <&cmu_top CLK_ACLK_G2D_400>; clock-names = "bus"; operating-points-v2 = <&bus_g2d_400_opp_table>; status = "disabled"; }; bus_noc2: bus9 { compatible = "samsung,exynos-bus"; clocks = <&cmu_mif CLK_ACLK_BUS2_400>; clock-names = "bus"; operating-points-v2 = <&bus_noc2_opp_table>; status = "disabled"; }; bus_g2d_400_opp_table: opp_table2 { compatible = "operating-points-v2"; opp-shared; opp-400000000 { opp-hz = /bits/ 64 <400000000>; opp-microvolt = <1075000>; required-opps = <&noc2_400>; }; opp-267000000 { opp-hz = /bits/ 64 <267000000>; opp-microvolt = <1000000>; required-opps = <&noc2_200>; }; opp-200000000 { opp-hz = /bits/ 64 <200000000>; opp-microvolt = <975000>; required-opps = <&noc2_200>; }; opp-160000000 { opp-hz = /bits/ 64 <160000000>; opp-microvolt = <962500>; required-opps = <&noc2_134>; }; opp-134000000 { opp-hz = /bits/ 64 <134000000>; opp-microvolt = <950000>; required-opps = <&noc2_134>; }; opp-100000000 { opp-hz = /bits/ 64 <100000000>; opp-microvolt = <937500>; required-opps = <&noc2_100>; }; }; bus_noc2_opp_table: opp_table6 { compatible = "operating-points-v2"; noc2_400: opp-400000000 { opp-hz = /bits/ 64 <400000000>; }; noc2_200: opp-200000000 { opp-hz = /bits/ 64 <200000000>; }; noc2_134: opp-134000000 { opp-hz = /bits/ 64 <134000000>; }; noc2_100: opp-100000000 { opp-hz = /bits/ 64 <100000000>; }; }; -Saravana v2 -> v3: - Rebased onto linux-next. - Added documentation comment for new fields. - Added support for lazy required-opps linking. - Updated Ack/Reviewed-bys. v1 -> v2: - Cached OPP table reference in devfreq to avoid looking up every time. - Renamed variable in passive governor to be more intuitive. - Updated cover letter with examples. Saravana Kannan (5): OPP: Allow required-opps even if the device doesn't have power-domains OPP: Add function to look up required OPP's for a given OPP OPP: Improve require-opps linking PM / devfreq: Cache OPP table reference in devfreq PM / devfreq: Add required OPPs support to passive governor drivers/devfreq/devfreq.c | 6 ++ drivers/devfreq/governor_passive.c | 20 ++++-- drivers/opp/core.c | 84 ++++++++++++++++++++++--- drivers/opp/of.c | 98 +++++++++++++----------------- drivers/opp/opp.h | 5 ++ include/linux/devfreq.h | 2 + include/linux/pm_opp.h | 11 ++++ 7 files changed, 156 insertions(+), 70 deletions(-)