From patchwork Wed Jun 28 10:56:51 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Abel Vesa X-Patchwork-Id: 697311 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 32BD8C0015E for ; Wed, 28 Jun 2023 10:57:29 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230361AbjF1K51 (ORCPT ); Wed, 28 Jun 2023 06:57:27 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:60640 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230456AbjF1K5C (ORCPT ); Wed, 28 Jun 2023 06:57:02 -0400 Received: from mail-ej1-x629.google.com (mail-ej1-x629.google.com [IPv6:2a00:1450:4864:20::629]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id EAE058F for ; Wed, 28 Jun 2023 03:56:59 -0700 (PDT) Received: by mail-ej1-x629.google.com with SMTP id a640c23a62f3a-98dfb3f9af6so661345466b.2 for ; Wed, 28 Jun 2023 03:56:59 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; t=1687949818; x=1690541818; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=QoU70+X2sNAFT4uGxGgFO5/mS/RvfhIZM1VSnqbKkks=; b=yNEfLuqzNx3cDoeEIY88b/nsT6aiugtedzyOR3wsqjxHzkEQiowKXnpCBRhuwR9Wh4 2n5Sty5d3XHO9IkbQGkjaA3oUBZmdd4M2kalIZ+Sx6YoNSHqfvpho8+Squ1SEI+0iicU C5IP8OpT6/Eatnl6e4TdQWRpO5kunzN7/oXqe/BuZiypVnAUHtTuQop+ImQEMtPc5/ry ttBECp71sF05RWR3lsUih+oo0nCBZiNSlazXjtrgr9HwD8OyvNaLHJUSTR0Y8LMLp61g e1JVCQGqDCXKcqIcTgOcq1j3yEa6GZi9OdCjdNnYpNfhF6ifAisG+6+afub0kkczzd+N 13vQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20221208; t=1687949818; x=1690541818; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=QoU70+X2sNAFT4uGxGgFO5/mS/RvfhIZM1VSnqbKkks=; b=M2MvgliOFsxl6rpMkQXHkjgnrrIMbQKQZwHPl1mn/gzy+3879pmOgOk9Viek4bvetD t9pEhjf0EidowGFd1aHHsbRai6ruBmpyeG6unsQuFX2WjomLjM18fLMquKbDLeuGneTB 6nlNRQMTeenYk+C9l6uMxGoMwhZ/6gj4jD31kyoFEL6ySafwpPJyrzOKJ0abQElN/Mh2 Vcy4czhPtHFmMOs9By3vabfBDM2aYjXvKIsqu2pg8QRSS/cwqBaZId09geuTW5x7ZBqR 9SnB44Y10HI9NJZ4FKahvoLwrJfiXaEC1Vz71LzspINvdWFeVImuUs/AQFqQW+5hoRhp IAIA== X-Gm-Message-State: AC+VfDwRSKmTW/0P8IFfAK2BebTGDXaqs49Am+r9gXcOlAQDI8jTzETd XV9xKS7gftSvXaeL5mMpCt3Y6A== X-Google-Smtp-Source: ACHHUZ5R8auDPDyKq0JTaO686eE46cVC/Q3aPkg5gZJ1ek6Fc754AwN952k1QIbJx2Ey9n3wIrfCEw== X-Received: by 2002:a17:906:da8b:b0:982:26c5:6525 with SMTP id xh11-20020a170906da8b00b0098226c56525mr34333689ejb.60.1687949818190; Wed, 28 Jun 2023 03:56:58 -0700 (PDT) Received: from hackbox.lan ([62.231.110.100]) by smtp.gmail.com with ESMTPSA id e8-20020a1709062c0800b0098921e1b064sm5544678ejh.181.2023.06.28.03.56.56 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 28 Jun 2023 03:56:57 -0700 (PDT) From: Abel Vesa To: "Rafael J . Wysocki" , Kevin Hilman , Ulf Hansson , avel Machek , Len Brown , Greg Kroah-Hartman , Bjorn Andersson , Andy Gross , Konrad Dybcio , Mike Turquette , Stephen Boyd , Taniya Das Cc: linux-pm@vger.kernel.org, Linux Kernel Mailing List , linux-arm-msm@vger.kernel.org Subject: [PATCH 1/2] PM: domains: Allow devices attached to genpd to be managed by HW Date: Wed, 28 Jun 2023 13:56:51 +0300 Message-Id: <20230628105652.1670316-2-abel.vesa@linaro.org> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20230628105652.1670316-1-abel.vesa@linaro.org> References: <20230628105652.1670316-1-abel.vesa@linaro.org> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-arm-msm@vger.kernel.org From: Ulf Hansson Some power-domains may be capable of relying on the HW to control the power for a device that's hooked up to it. Typically, for these kinds of configurations the device doesn't really need to be attached to a PM domain (genpd), from Linux point of view. However, in some cases the behaviour of the power-domain and its device can be changed in runtime. To allow a consumer driver to change the behaviour of the PM domain for its device, let's provide a new function, dev_pm_genpd_set_hwmode(). Moreover, let's add a corresponding optional genpd callback, ->set_hwmode_dev(), which the genpd provider should implement if it can support switching between HW controlled mode and SW controlled mode. Signed-off-by: Ulf Hansson Signed-off-by: Abel Vesa --- drivers/base/power/domain.c | 66 +++++++++++++++++++++++++++++++++++++ include/linux/pm_domain.h | 15 +++++++++ 2 files changed, 81 insertions(+) diff --git a/drivers/base/power/domain.c b/drivers/base/power/domain.c index 5cb2023581d4..23286853d1d0 100644 --- a/drivers/base/power/domain.c +++ b/drivers/base/power/domain.c @@ -541,6 +541,72 @@ void dev_pm_genpd_synced_poweroff(struct device *dev) } EXPORT_SYMBOL_GPL(dev_pm_genpd_synced_poweroff); +/** + * dev_pm_genpd_set_hwmode - Set the HW mode for the device and its PM domain. + * + * @dev: Device for which the HW-mode should be changed. + * @enable: Value to set or unset the HW-mode. + * + * Some PM domains can rely on HW signals to control the power for a device. To + * allow a consumer driver to switch the behaviour for its device in runtime, + * which may be beneficial from a latency or energy point of view, this function + * may be called. + * + * It is assumed that the users guarantee that the genpd wouldn't be detached + * while this routine is getting called. + * + * Returns 0 on success and negative error values on failures. + */ +int dev_pm_genpd_set_hwmode(struct device *dev, bool enable) +{ + struct generic_pm_domain *genpd; + int ret = 0; + + genpd = dev_to_genpd_safe(dev); + if (!genpd) + return -ENODEV; + + if (!genpd->set_hwmode_dev) + return -EOPNOTSUPP; + + genpd_lock(genpd); + + if (dev_gpd_data(dev)->hw_mode == enable) + goto out; + + ret = genpd->set_hwmode_dev(genpd, dev, enable); + if (!ret) + dev_gpd_data(dev)->hw_mode = enable; + +out: + genpd_unlock(genpd); + return ret; +} +EXPORT_SYMBOL_GPL(dev_pm_genpd_set_hwmode); + +/** + * dev_pm_genpd_get_hwmode - Get the HW mode setting for the device. + * + * @dev: Device for which the current HW-mode setting should be fetched. + * + * This helper function allows consumer drivers to fetch the current HW mode + * setting of its the device. + * + * It is assumed that the users guarantee that the genpd wouldn't be detached + * while this routine is getting called. + */ +bool dev_pm_genpd_get_hwmode(struct device *dev) +{ + struct generic_pm_domain *genpd; + + genpd = dev_to_genpd_safe(dev); + if (!genpd) + return false; + + return dev_gpd_data(dev)->hw_mode; +} +EXPORT_SYMBOL_GPL(dev_pm_genpd_get_hwmode); + static int _genpd_power_on(struct generic_pm_domain *genpd, bool timed) { unsigned int state_idx = genpd->state_idx; diff --git a/include/linux/pm_domain.h b/include/linux/pm_domain.h index f776fb93eaa0..8f60c36851d5 100644 --- a/include/linux/pm_domain.h +++ b/include/linux/pm_domain.h @@ -146,6 +146,8 @@ struct generic_pm_domain { int (*set_performance_state)(struct generic_pm_domain *genpd, unsigned int state); struct gpd_dev_ops dev_ops; + int (*set_hwmode_dev)(struct generic_pm_domain *domain, + struct device *dev, bool enable); int (*attach_dev)(struct generic_pm_domain *domain, struct device *dev); void (*detach_dev)(struct generic_pm_domain *domain, @@ -208,6 +210,7 @@ struct generic_pm_domain_data { unsigned int performance_state; unsigned int default_pstate; unsigned int rpm_pstate; + bool hw_mode; void *data; }; @@ -237,6 +240,8 @@ int dev_pm_genpd_remove_notifier(struct device *dev); void dev_pm_genpd_set_next_wakeup(struct device *dev, ktime_t next); ktime_t dev_pm_genpd_get_next_hrtimer(struct device *dev); void dev_pm_genpd_synced_poweroff(struct device *dev); +int dev_pm_genpd_set_hwmode(struct device *dev, bool enable); +bool dev_pm_genpd_get_hwmode(struct device *dev); extern struct dev_power_governor simple_qos_governor; extern struct dev_power_governor pm_domain_always_on_gov; @@ -305,6 +310,16 @@ static inline ktime_t dev_pm_genpd_get_next_hrtimer(struct device *dev) static inline void dev_pm_genpd_synced_poweroff(struct device *dev) { } +static inline int dev_pm_genpd_set_hwmode(struct device *dev, bool enable) +{ + return -EOPNOTSUPP; +} + +static inline bool dev_pm_genpd_get_hwmode(struct device *dev) +{ + return false; +} + #define simple_qos_governor (*(struct dev_power_governor *)(NULL)) #define pm_domain_always_on_gov (*(struct dev_power_governor *)(NULL)) #endif