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=-2.3 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, 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 07C16C2D0E4 for ; Tue, 17 Nov 2020 15:56:42 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 8A1A32222C for ; Tue, 17 Nov 2020 15:56:41 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="IKW/l9Fy" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726509AbgKQP4U (ORCPT ); Tue, 17 Nov 2020 10:56:20 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:55162 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725767AbgKQP4U (ORCPT ); Tue, 17 Nov 2020 10:56:20 -0500 Received: from mail-wr1-x42c.google.com (mail-wr1-x42c.google.com [IPv6:2a00:1450:4864:20::42c]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 93FA0C0613CF for ; Tue, 17 Nov 2020 07:56:18 -0800 (PST) Received: by mail-wr1-x42c.google.com with SMTP id 23so23654308wrc.8 for ; Tue, 17 Nov 2020 07:56:18 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=to:cc:from:subject:message-id:date:user-agent:mime-version :content-transfer-encoding; bh=DDCfmqxMENHjETYXvv/5+Z4ZTHuhvLOIXeEU3+XDkaw=; b=IKW/l9FynsJ3/qMPI1qvox5zbn/yFeCXrgM6wdnXQC881N0aJryK63RCWTfU9D/bIv VNmenYUviqu+52NwAZEZX7vkfX5khMT7a1tklJxJvCntwVUAUK65/+qaoZbQexoy7irV ZX96CgzkjbdyFL348DdRDStBouNhWWuNhGy3HVUL+egspe4kVlXXVxoJ20OiyCNeQ+97 NpMYXPEYp0h6nGN6P7oksMzPPPih1axIhV29ljPFyBYk6O+7u4gACaSxSoSfHREIUKT7 cFveSzz2JXDb7Ng4EVDSsm6kdYARywkP7CFMVFQuow/N/gVb9tkqghAfNMB7lV9xoAAO zeVg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:to:cc:from:subject:message-id:date:user-agent :mime-version:content-transfer-encoding; bh=DDCfmqxMENHjETYXvv/5+Z4ZTHuhvLOIXeEU3+XDkaw=; b=AUnqLf1hXRaKZjB8B2grVbyX4asf8hOlF6QLlVGm1UQqVVOk8dGA2P9hDlgles6Rvu B44+XFFSqC9XhBxKJbdUfQY1mLavDCjHh6CXqzymnGtp0EwTYXKgWmolwiK+vKtTZhFn DMmEgYNqton57XGDaVokWE0go5YWcMjjBjySCrknQaAGba7fKzaGBGzoK+RbOP9bUYqb ztLBhF+eJKlY74iVZJ2kdvqT8UPEM9aCfmLfHMEgbIT6OQZ658K+ioKVOHyNy0gUcvrJ bYqrkkorYolwYz6dzDJJ8p8b35Q1WuCYeO9zBE7svTBAYiTq6t7NXaRKDRMK/fNPrNm6 BHJw== X-Gm-Message-State: AOAM531VZg5JRCw6t84KHLeioDI7diS0Oc8ekyuEYwjoPBw/rYWk1Pfd SkU59+czktpBu4CGUtvyYfWZPj5WP42/lA== X-Google-Smtp-Source: ABdhPJx2JcB1YJJd6d8KmnTh64iXhTmBVHzNR+z7URdJgvNZqjtF7VE9YwbFRhZN2yHB6Kfimh8fvw== X-Received: by 2002:adf:d4c6:: with SMTP id w6mr169395wrk.71.1605628577053; Tue, 17 Nov 2020 07:56:17 -0800 (PST) Received: from ?IPv6:2003:ea:8f23:2800:3907:f821:c784:61d9? (p200300ea8f2328003907f821c78461d9.dip0.t-ipconnect.de. [2003:ea:8f23:2800:3907:f821:c784:61d9]) by smtp.googlemail.com with ESMTPSA id p4sm28578050wrm.51.2020.11.17.07.56.16 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Tue, 17 Nov 2020 07:56:16 -0800 (PST) To: Bjorn Helgaas Cc: "linux-pci@vger.kernel.org" From: Heiner Kallweit Subject: Time to re-enable Runtime PM per default for PCI devcies? Message-ID: <79940973-b631-90f9-dbc4-9579c6000816@gmail.com> Date: Tue, 17 Nov 2020 16:56:09 +0100 User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:78.0) Gecko/20100101 Thunderbird/78.4.3 MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org More than 10 yrs ago Runtime PM was disabled per default by bb910a7040 ("PCI/PM Runtime: Make runtime PM of PCI devices inactive by default"). Reason given: "avoid breakage on systems where ACPI-based wake-up is known to fail for some devices" Unfortunately the commit message doesn't mention any affected devices or systems. With Runtime PM disabled e.g. the PHY on network devices may remain powered up even with no cable plugged in, affecting battery lifetime on mobile devices. Currently we have to rely on the respective distro or user to enable Runtime PM via sysfs (echo auto > power/control). Some devices work around this restriction by calling pm_runtime_allow in their probe routine, even though that's not recommended by https://www.kernel.org/doc/Documentation/power/pci.txt Disabling Runtime PM per default seems to be a big hammer, a quirk for affected devices / systems may had been better. And we still have the option to disable Runtime PM for selected devices via sysfs. So, to cut a long story short: Wouldn't it be time to remove this restriction?