From patchwork Fri Nov 6 16:48:09 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Lina Iyer X-Patchwork-Id: 11887415 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 99F8E921 for ; Fri, 6 Nov 2020 16:49:08 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 71D46217A0 for ; Fri, 6 Nov 2020 16:49:08 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=mg.codeaurora.org header.i=@mg.codeaurora.org header.b="CrF8v2vQ" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727158AbgKFQtH (ORCPT ); Fri, 6 Nov 2020 11:49:07 -0500 Received: from m42-4.mailgun.net ([69.72.42.4]:54211 "EHLO m42-4.mailgun.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727186AbgKFQtH (ORCPT ); Fri, 6 Nov 2020 11:49:07 -0500 DKIM-Signature: a=rsa-sha256; v=1; c=relaxed/relaxed; d=mg.codeaurora.org; q=dns/txt; s=smtp; t=1604681347; h=Content-Transfer-Encoding: MIME-Version: Message-Id: Date: Subject: Cc: To: From: Sender; bh=mmDY3vrSkUBVocMRrTBePZzPrbDq54E0u3YNqfpt3f4=; b=CrF8v2vQsFPjJBLLNq4scS/9RODnSbxOjxSW0x6gZTQWIg4S4WUUGik/ezyOzG9E+Up2g75Y BYFDglA0FU27/QVF7YhIb7FJcwvgI71Vp7fCrfkWNHICo5+L4SSDBiTQ3XC1DvVLrb6T8dez qy5I+AQta2P4gfDXQLbEZKQgZSM= X-Mailgun-Sending-Ip: 69.72.42.4 X-Mailgun-Sid: WyI5ZDFmMiIsICJsaW51eC1wbUB2Z2VyLmtlcm5lbC5vcmciLCAiYmU5ZTRhIl0= Received: from smtp.codeaurora.org (ec2-35-166-182-171.us-west-2.compute.amazonaws.com [35.166.182.171]) by smtp-out-n06.prod.us-east-1.postgun.com with SMTP id 5fa57e56b82e1b98c66c57e9 (version=TLS1.2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256); Fri, 06 Nov 2020 16:48:22 GMT Sender: ilina=codeaurora.org@mg.codeaurora.org Received: by smtp.codeaurora.org (Postfix, from userid 1001) id 20679C433C9; Fri, 6 Nov 2020 16:48:22 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-caf-mail-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-2.9 required=2.0 tests=ALL_TRUSTED,BAYES_00,SPF_FAIL, URIBL_BLOCKED autolearn=no autolearn_force=no version=3.4.0 Received: from codeaurora.org (i-global254.qualcomm.com [199.106.103.254]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-SHA256 (128/128 bits)) (No client certificate requested) (Authenticated sender: ilina) by smtp.codeaurora.org (Postfix) with ESMTPSA id 0F148C433C8; Fri, 6 Nov 2020 16:48:20 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 smtp.codeaurora.org 0F148C433C8 Authentication-Results: aws-us-west-2-caf-mail-1.web.codeaurora.org; dmarc=none (p=none dis=none) header.from=codeaurora.org Authentication-Results: aws-us-west-2-caf-mail-1.web.codeaurora.org; spf=fail smtp.mailfrom=ilina@codeaurora.org From: Lina Iyer To: rjw@rjwysocki.net, ulf.hansson@linaro.org Cc: linux-pm@vger.kernel.org, linux-arm-msm@vger.kernel.org, Lina Iyer Subject: [PATCH v5 0/2] Better domain idle from device wakeup patterns Date: Fri, 6 Nov 2020 09:48:09 -0700 Message-Id: <20201106164811.3698-1-ilina@codeaurora.org> X-Mailer: git-send-email 2.29.2 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-pm@vger.kernel.org Changes since v4 [4]: - Address review comments Changes since v3 [3]: - Move the next_wakeup info of the device deeper into the device's domain data. This should avoid overhead for devices that do not have a predictable wakeup pattern. Changes since v2: - Fix unwanted change Changes since v1 [2]: - Update documentation and commit text - Remove check for runtime PM when setting next_event - Fix kernel-test robot reported issue Changes since RFC [1]: - Organized the code to make it cleaner - Fixed some issues with idle state determination - Add documentation and update commit text Hello, I was looking for an option to do better power management for some domains where the devices enter runtime PM in a predictable fashion. For example a display device that sends a vsync interrupt every 16 ms for a 60 Hz panel. These interrupts are not timer interrupts but tend to interrupt periodically to service the workflow and the devices and domains may go back to idle soon after. Two domains are affected by this - the device's PM domain and the CPU PM domain. As a first step, I am looking to solve for the device's PM domain idle state (and hopefully solve for the CPU PM domains subsequently). The PM domain could have multiple idle states and/or the enter/exit latencies could be high. In either case, it may not always be beneficial to power off the domain, only to turn it back on before satisfying the idle state residency. When the wakeup is known for the device, we could use that to determine the worthiness of entering a domain idle state. Only the device can tell us when the future event would be and that could change as the usecase changes. Like, when the panel refresh rate increases to 120 Hz. If this information was made available to runtime PM, we could use that in the domain governor to determine a suitable idle state. This is the idea behind these patches. Would appreciate your thoughts on this. Thanks, Lina [1]. https://lore.kernel.org/linux-pm/010101746eccb270-05beb27f-e1e4-40eb-92da-ad1bb48feb41-000000@us-west-2.amazonses.com/T/ [2]. https://lore.kernel.org/linux-pm/20201012223400.23609-3-ilina@codeaurora.org/T/#u [3]. https://lore.kernel.org/linux-pm/20201015193807.17423-1-ilina@codeaurora.org/ [4]. https://www.spinics.net/lists/linux-arm-msm/msg74322.html Lina Iyer (2): PM / domains: inform PM domain of a device's next wakeup PM / Domains: use device's next wakeup to determine domain idle state drivers/base/power/domain.c | 36 +++++++++++++ drivers/base/power/domain_governor.c | 81 ++++++++++++++++++++++++++-- include/linux/pm_domain.h | 9 ++++ 3 files changed, 121 insertions(+), 5 deletions(-)