From patchwork Tue Oct 20 18:04:11 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Lina Iyer X-Patchwork-Id: 286756 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=-6.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID, HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI, SPF_HELO_NONE, SPF_PASS, USER_AGENT_GIT 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 45020C388F7 for ; Tue, 20 Oct 2020 18:04:42 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id CA7DC2076A for ; Tue, 20 Oct 2020 18:04:41 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=mg.codeaurora.org header.i=@mg.codeaurora.org header.b="tNvjg8uy" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1732752AbgJTSEl (ORCPT ); Tue, 20 Oct 2020 14:04:41 -0400 Received: from z5.mailgun.us ([104.130.96.5]:64429 "EHLO z5.mailgun.us" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2408912AbgJTSEl (ORCPT ); Tue, 20 Oct 2020 14:04:41 -0400 DKIM-Signature: a=rsa-sha256; v=1; c=relaxed/relaxed; d=mg.codeaurora.org; q=dns/txt; s=smtp; t=1603217080; h=Content-Transfer-Encoding: MIME-Version: Message-Id: Date: Subject: Cc: To: From: Sender; bh=O6TrI1os+Nq6JaPzk+jrqIU+a9nVuxC0Tp0EqiN3xYU=; b=tNvjg8uypEJK7Hhamz1WZSjIfZ8jp/kr+LLnhBJwexTJZSxOe+EojFLPyPJLSFKozE4oDH+6 Vy9JPERv2+XdxKlPsWlHF9vtvW7Tb+v9ZNxOBRCw/z+9MS4+r59s/xvRNckp4eck6omrMXxE gFmtE9LmLULlJxfN6jv3DhPcT7Y= X-Mailgun-Sending-Ip: 104.130.96.5 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-n05.prod.us-west-2.postgun.com with SMTP id 5f8f26ae319d4e9cb581cd1b (version=TLS1.2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256); Tue, 20 Oct 2020 18:04:30 GMT Sender: ilina=codeaurora.org@mg.codeaurora.org Received: by smtp.codeaurora.org (Postfix, from userid 1001) id A8E36C43385; Tue, 20 Oct 2020 18:04:30 +0000 (UTC) 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 80A5EC433CB; Tue, 20 Oct 2020 18:04:29 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 smtp.codeaurora.org 80A5EC433CB 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, linux-pm@vger.kernel.org Cc: linux-arm-msm@vger.kernel.org, Lina Iyer Subject: [PATCH v4 0/2] Better domain idle from device wakeup patterns Date: Tue, 20 Oct 2020 12:04:11 -0600 Message-Id: <20201020180413.32225-1-ilina@codeaurora.org> X-Mailer: git-send-email 2.28.0 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-pm@vger.kernel.org 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/ 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 | 84 ++++++++++++++++++++++++++-- include/linux/pm_domain.h | 9 +++ 3 files changed, 124 insertions(+), 5 deletions(-) Reviewed-by: Ulf Hansson