From patchwork Wed Jan 20 15:50:41 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Lina Iyer X-Patchwork-Id: 12032773 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=-16.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham 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 05B7BC433DB for ; Wed, 20 Jan 2021 15:53:39 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id BECC923381 for ; Wed, 20 Jan 2021 15:53:38 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1732991AbhATPxM (ORCPT ); Wed, 20 Jan 2021 10:53:12 -0500 Received: from a1.mail.mailgun.net ([198.61.254.60]:12135 "EHLO a1.mail.mailgun.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2391147AbhATPvp (ORCPT ); Wed, 20 Jan 2021 10:51:45 -0500 DKIM-Signature: a=rsa-sha256; v=1; c=relaxed/relaxed; d=mg.codeaurora.org; q=dns/txt; s=smtp; t=1611157884; h=Content-Transfer-Encoding: MIME-Version: References: In-Reply-To: Message-Id: Date: Subject: Cc: To: From: Sender; bh=Au7S6xU1ZhfwUiSwKsWHZZP9ZAyTtKF3+PizlpHKsSY=; b=gIIq8OgRwzB0ScWfX5iVJO3wjSn7VReeMo9TqodcfySj/ZUnGhgi1XN94ejQbDBSoxuIIUWu Bss2a+a8sXViNK1MTPm/eDEeQlNfp9fGZOYKeh9gbrNVHvO6kdes9PNTpEmqoxRoD1qe4Eay jwPJuAC4VpJyb+ZtXEZo2wxsN2w= X-Mailgun-Sending-Ip: 198.61.254.60 X-Mailgun-Sid: WyI1MzIzYiIsICJsaW51eC1hcm0tbXNtQHZnZXIua2VybmVsLm9yZyIsICJiZTllNGEiXQ== Received: from smtp.codeaurora.org (ec2-35-166-182-171.us-west-2.compute.amazonaws.com [35.166.182.171]) by smtp-out-n02.prod.us-west-2.postgun.com with SMTP id 600851585677aca7bd0e846d (version=TLS1.2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256); Wed, 20 Jan 2021 15:50:48 GMT Sender: ilina=codeaurora.org@mg.codeaurora.org Received: by smtp.codeaurora.org (Postfix, from userid 1001) id 51A82C433ED; Wed, 20 Jan 2021 15:50:48 +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 31E07C433C6; Wed, 20 Jan 2021 15:50:47 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 smtp.codeaurora.org 31E07C433C6 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: ulf.hansson@linaro.org, rjw@rjwysocki.net Cc: linux-pm@vger.kernel.org, linux-arm-msm@vger.kernel.org, Lina Iyer Subject: [PATCH v9 1/2] PM / domains: inform PM domain of a device's next wakeup Date: Wed, 20 Jan 2021 08:50:41 -0700 Message-Id: <20210120155042.28975-2-ilina@codeaurora.org> X-Mailer: git-send-email 2.30.0 In-Reply-To: <20210120155042.28975-1-ilina@codeaurora.org> References: <20210120155042.28975-1-ilina@codeaurora.org> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-arm-msm@vger.kernel.org Some devices may have a predictable interrupt pattern while executing usecases. An example would be the VSYNC interrupt associated with display devices. A 60 Hz display could cause a interrupt every 16 ms. If the device were in a PM domain, the domain would need to be powered up for device to resume and handle the interrupt. Entering a domain idle state saves power, only if the residency of the idle state is met. Without knowing the idle duration of the domain, the governor would just choose the deepest idle state that matches the QoS requirements. The domain might be powered off just as the device is expecting to wake up. If devices could inform PM frameworks of their next event, the parent PM domain's idle duration can be determined. So let's add the dev_pm_genpd_set_next_wakeup() API for the device to inform PM domains of the impending wakeup. This information will be the domain governor to determine the best idle state given the wakeup. Signed-off-by: Lina Iyer Reviewed-by: Ulf Hansson --- Changes in v9: - Check if device is part of genpd. Changes in v8: - Update documentation. Add Reviewed-by tag. Changes in v7: - Simplify and set next-wakeup locklessly Changes in v6: - Update documentation Changes in v5: - Fix commit text as pointed by Ulf - Use -EOPNOTSUPP Changes in v4: - Use PM domain data to store next_wakeup - Drop runtime PM documentation Changes in v3: - Fix unwanted change Changes in v2: - Update documentation - Remove runtime PM enabled check - Update commit text --- drivers/base/power/domain.c | 30 ++++++++++++++++++++++++++++++ include/linux/pm_domain.h | 6 ++++++ 2 files changed, 36 insertions(+) diff --git a/drivers/base/power/domain.c b/drivers/base/power/domain.c index 9a14eedacb92..014033c7c287 100644 --- a/drivers/base/power/domain.c +++ b/drivers/base/power/domain.c @@ -423,6 +423,35 @@ int dev_pm_genpd_set_performance_state(struct device *dev, unsigned int state) } EXPORT_SYMBOL_GPL(dev_pm_genpd_set_performance_state); +/** + * dev_pm_genpd_set_next_wakeup - Notify PM framework of an impending wakeup. + * + * @dev: Device to handle + * @next: impending interrupt/wakeup for the device + * + * + * Allow devices to inform of the next wakeup. It's assumed that the users + * guarantee that the genpd wouldn't be detached while this routine is getting + * called. Additionally, it's also assumed that @dev isn't runtime suspended + * (RPM_SUSPENDED)." + * Although devices are expected to update the next_wakeup after the end of + * their usecase as well, it is possible the devices themselves may not know + * about that, so stale @next will be ignored when powering off the domain. + */ +void dev_pm_genpd_set_next_wakeup(struct device *dev, ktime_t next) +{ + struct generic_pm_domain_data *gpd_data; + struct generic_pm_domain *genpd; + + genpd = dev_to_genpd_safe(dev); + if (!genpd) + return; + + gpd_data = to_gpd_data(dev->power.subsys_data->domain_data); + gpd_data->next_wakeup = next; +} +EXPORT_SYMBOL_GPL(dev_pm_genpd_set_next_wakeup); + static int _genpd_power_on(struct generic_pm_domain *genpd, bool timed) { unsigned int state_idx = genpd->state_idx; @@ -1465,6 +1494,7 @@ static struct generic_pm_domain_data *genpd_alloc_dev_data(struct device *dev) gpd_data->td.constraint_changed = true; gpd_data->td.effective_constraint_ns = PM_QOS_RESUME_LATENCY_NO_CONSTRAINT_NS; gpd_data->nb.notifier_call = genpd_dev_pm_qos_notifier; + gpd_data->next_wakeup = KTIME_MAX; spin_lock_irq(&dev->power.lock); diff --git a/include/linux/pm_domain.h b/include/linux/pm_domain.h index 2ca919ae8d36..735583c0bc6d 100644 --- a/include/linux/pm_domain.h +++ b/include/linux/pm_domain.h @@ -9,6 +9,7 @@ #define _LINUX_PM_DOMAIN_H #include +#include #include #include #include @@ -191,6 +192,7 @@ struct generic_pm_domain_data { struct notifier_block *power_nb; int cpu; unsigned int performance_state; + ktime_t next_wakeup; void *data; }; @@ -217,6 +219,7 @@ int pm_genpd_remove(struct generic_pm_domain *genpd); int dev_pm_genpd_set_performance_state(struct device *dev, unsigned int state); int dev_pm_genpd_add_notifier(struct device *dev, struct notifier_block *nb); int dev_pm_genpd_remove_notifier(struct device *dev); +void dev_pm_genpd_set_next_wakeup(struct device *dev, ktime_t next); extern struct dev_power_governor simple_qos_governor; extern struct dev_power_governor pm_domain_always_on_gov; @@ -275,6 +278,9 @@ static inline int dev_pm_genpd_remove_notifier(struct device *dev) return -EOPNOTSUPP; } +static inline void dev_pm_genpd_set_next_wakeup(struct device *dev, ktime_t next) +{ } + #define simple_qos_governor (*(struct dev_power_governor *)(NULL)) #define pm_domain_always_on_gov (*(struct dev_power_governor *)(NULL)) #endif