From patchwork Thu Nov 26 13:47:29 2015 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Chanwoo Choi X-Patchwork-Id: 7707151 Return-Path: X-Original-To: patchwork-linux-samsung-soc@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork1.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.136]) by patchwork1.web.kernel.org (Postfix) with ESMTP id 41E579F2EC for ; Thu, 26 Nov 2015 13:52:04 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 037C020771 for ; Thu, 26 Nov 2015 13:52:03 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 96DAE205BA for ; Thu, 26 Nov 2015 13:52:00 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752636AbbKZNvn (ORCPT ); Thu, 26 Nov 2015 08:51:43 -0500 Received: from mailout3.samsung.com ([203.254.224.33]:57988 "EHLO mailout3.samsung.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751532AbbKZNrq (ORCPT ); Thu, 26 Nov 2015 08:47:46 -0500 Received: from epcpsbgr3.samsung.com (u143.gpu120.samsung.co.kr [203.254.230.143]) by mailout3.samsung.com (Oracle Communications Messaging Server 7.0.5.31.0 64bit (built May 5 2014)) with ESMTP id <0NYF00R6LCZHHH60@mailout3.samsung.com>; Thu, 26 Nov 2015 22:47:41 +0900 (KST) Received: from epcpsbgm2new.samsung.com ( [172.20.52.112]) by epcpsbgr3.samsung.com (EPCPMTA) with SMTP id 0A.1A.30395.D7D07565; Thu, 26 Nov 2015 22:47:41 +0900 (KST) X-AuditID: cbfee68f-f79666d0000076bb-af-56570d7d2f52 Received: from epmmp1.local.host ( [203.254.227.16]) by epcpsbgm2new.samsung.com (EPCPMTA) with SMTP id B0.AF.00996.D7D07565; Thu, 26 Nov 2015 22:47:41 +0900 (KST) Received: from chan.10.32.193.11 ([10.252.81.195]) by mmp1.samsung.com (Oracle Communications Messaging Server 7.0.5.31.0 64bit (built May 5 2014)) with ESMTPA id <0NYF00D4UCZGTXL0@mmp1.samsung.com>; Thu, 26 Nov 2015 22:47:40 +0900 (KST) From: Chanwoo Choi To: myungjoo.ham@samsung.com, kyungmin.park@samsung.com, kgene@kernel.org, k.kozlowski@samsung.com Cc: robh+dt@kernel.org, pawel.moll@arm.com, mark.rutland@arm.com, ijc+devicetree@hellion.org.uk, galak@codeaurora.org, linux@arm.linux.org.uk, tjakobi@math.uni-bielefeld.de, cw00.choi@samsung.com, linux-kernel@vger.kernel.org, linux-pm@vger.kernel.org, linux-samsung-soc@vger.kernel.org, devicetree@vger.kernel.org Subject: [RFC PATCH 05/15] PM / devfreq: Add new passive governor Date: Thu, 26 Nov 2015 22:47:29 +0900 Message-id: <1448545659-32287-6-git-send-email-cw00.choi@samsung.com> X-Mailer: git-send-email 1.8.0 In-reply-to: <1448545659-32287-1-git-send-email-cw00.choi@samsung.com> References: <1448545659-32287-1-git-send-email-cw00.choi@samsung.com> X-Brightmail-Tracker: H4sIAAAAAAAAA+NgFprKIsWRmVeSWpSXmKPExsWyRsSkQLeWNzzM4Pp1UYvrX56zWsw/co7V ov/NQlaLc69WMlq8fmFo0f/4NbPF2aY37BaXd81hs/jce4TRYsb5fUwWty/zWiy9fhHIaFzB ZjFh+loWi9a9R9gt2lZ/YHUQ8Fgzbw2jR0tzD5vH5b5eJo+Vy7+weWxa1cnm8e8Yu0ffllWM Hp83yQVwRHHZpKTmZJalFunbJXBlHJ73g7HgmG/Fj5nz2RsYux26GDk5JARMJPZcOsQKYYtJ XLi3nq2LkYtDSGAFo8SlPQ3MMEXvHnYxQSSWMkpc2PSaGcL5wihx8/EERpAqNgEtif0vbrCB 2CICKRJ/b85mBCliFjjEJHHm3RGgdg4OYQFHia8bwaayCKhKPJl0HayeV8BV4sHXo4wQ2+Qk Pux5xA5icwq4SZy6MgksLgRUM/ljD9h5EgJf2SW6dhxmhxgkIPFt8iEWkPkSArISmw5AXS0p cXDFDZYJjMILGBlWMYqmFiQXFCelFxnrFSfmFpfmpesl5+duYgTG1ul/z/p3MN49YH2IUYCD UYmHt8A2LEyINbGsuDL3EKMp0IaJzFKiyfnACM4riTc0NjOyMDUxNTYytzRTEuddKPUzWEgg PbEkNTs1tSC1KL6oNCe1+BAjEwenVAOjs9WvyyGx9bnlx1wP1BSnrtA8EWmRvfG0efpBEeFP lVVfp/NX6YY8PZTE/2dbStqy/hVWVvYP5ylW2K6t/HmHq3jZhxMqLp79J7d43EuXyXpm4Byz SG720iI5qTdLa14a6VUX32OqlVl8tTqDu+ppxWp3ybNy+jNDOkNvTU38/+BnyPy560yVWIoz Eg21mIuKEwHwYp5mqAIAAA== X-Brightmail-Tracker: H4sIAAAAAAAAA+NgFnrEIsWRmVeSWpSXmKPExsVy+t9jAd1a3vAwg1+r+Cyuf3nOajH/yDlW i/43C1ktzr1ayWjx+oWhRf/j18wWZ5vesFtc3jWHzeJz7xFGixnn9zFZ3L7Ma7H0+kUgo3EF m8WE6WtZLFr3HmG3aFv9gdVBwGPNvDWMHi3NPWwel/t6mTxWLv/C5rFpVSebx79j7B59W1Yx enzeJBfAEdXAaJORmpiSWqSQmpecn5KZl26r5B0c7xxvamZgqGtoaWGupJCXmJtqq+TiE6Dr lpkD9ICSQlliTilQKCCxuFhJ3w7ThNAQN10LmMYIXd+QILgeIwM0kLCGMePwvB+MBcd8K37M nM/ewNjt0MXIySEhYCLx7mEXE4QtJnHh3nq2LkYuDiGBpYwSFza9ZoZwvjBK3Hw8gRGkik1A S2L/ixtsILaIQIrE35uzGUGKmAUOMUmceXcEaBQHh7CAo8TXjcwgNSwCqhJPJl0Hq+cVcJV4 8PUoI8Q2OYkPex6xg9icAm4Sp65MAosLAdVM/tjDNoGRdwEjwypGidSC5ILipPRco7zUcr3i xNzi0rx0veT83E2M4Ph9Jr2D8fAu90OMAhyMSjy8BbZhYUKsiWXFlbmHGCU4mJVEeG+xhIcJ 8aYkVlalFuXHF5XmpBYfYjQFOmwis5Rocj4wteSVxBsam5gZWRqZG1oYGZsrifNe2O8XJiSQ nliSmp2aWpBaBNPHxMEp1cC48KR+ju5eYQZfrl7hrVr5snmXmg4W6BwTdwp8+Px0Yww7V0Gn 2SaZN6/NzrS81X72Kmum7cd77Psl7Ssnt2nr9bxk3pyW3nipUTOU+0aYouo6yaA9c499iCva 3CZ1S3Dt9j+79ISMWeLkJhUkR/J/njfh144i638OWvOf7jj46uZ8RY9N7tOVWIozEg21mIuK EwEWlDFU9QIAAA== DLP-Filter: Pass X-MTR: 20000000000000000@CPGS X-CFilter-Loop: Reflected Sender: linux-samsung-soc-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-samsung-soc@vger.kernel.org X-Spam-Status: No, score=-7.9 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_HI, RP_MATCHES_RCVD, UNPARSEABLE_RELAY autolearn=unavailable version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP This patch adds the new passive governor for DEVFREQ framework. The following governors are already present and used for DVFS (Dynamic Voltage and Frequency Scaling) drivers. The following governors are independently used for one device driver which don't give the influence to other device drviers and also don't receive the effect from other device drivers. - ondemand / performance / powersave / userspace The passive governor depends on operation of parent driver with specific governos extremely and is not able to decide the new frequency by oneself. According to the decided new frequency of parent driver with governor, the passive governor uses it to decide the appropriate frequency for own device driver. The passive governor must need the following information from device tree: - the source clock and OPP tables - the instance of parent device For exameple, there are one more devfreq device drivers which need to change their source clock according to their utilization on runtime. But, they share the same power line (e.g., regulator). So, specific device driver is operated as parent with ondemand governor and then the rest device driver with passive governor is influenced by parent device. Suggested-by: Myungjoo Ham Signed-off-by: Chanwoo Choi --- drivers/devfreq/Kconfig | 9 ++++ drivers/devfreq/Makefile | 1 + drivers/devfreq/devfreq.c | 47 ++++++++++++++++ drivers/devfreq/governor_passive.c | 108 +++++++++++++++++++++++++++++++++++++ include/linux/devfreq.h | 17 ++++++ 5 files changed, 182 insertions(+) create mode 100644 drivers/devfreq/governor_passive.c diff --git a/drivers/devfreq/Kconfig b/drivers/devfreq/Kconfig index 55ec774f794c..d03f635a93e1 100644 --- a/drivers/devfreq/Kconfig +++ b/drivers/devfreq/Kconfig @@ -64,6 +64,15 @@ config DEVFREQ_GOV_USERSPACE Otherwise, the governor does not change the frequnecy given at the initialization. +config DEVFREQ_GOV_PASSIVE + tristate "Passive" + help + Sets the frequency by other governors (simple_ondemand, performance, + powersave, usersapce) of a parent devfreq device. This governor + always has the dependency on the chosen frequency from paired + governor. This governor does not change the frequency by oneself + through sysfs entry. + comment "DEVFREQ Drivers" config ARM_EXYNOS_BUS_DEVFREQ diff --git a/drivers/devfreq/Makefile b/drivers/devfreq/Makefile index 375ebbb4fcfb..f81c313b4b79 100644 --- a/drivers/devfreq/Makefile +++ b/drivers/devfreq/Makefile @@ -4,6 +4,7 @@ obj-$(CONFIG_DEVFREQ_GOV_SIMPLE_ONDEMAND) += governor_simpleondemand.o obj-$(CONFIG_DEVFREQ_GOV_PERFORMANCE) += governor_performance.o obj-$(CONFIG_DEVFREQ_GOV_POWERSAVE) += governor_powersave.o obj-$(CONFIG_DEVFREQ_GOV_USERSPACE) += governor_userspace.o +obj-$(CONFIG_DEVFREQ_GOV_PASSIVE) += governor_passive.o # DEVFREQ Drivers obj-$(CONFIG_ARCH_EXYNOS) += exynos/ diff --git a/drivers/devfreq/devfreq.c b/drivers/devfreq/devfreq.c index 984c5e9e7bdd..15e58779e4c0 100644 --- a/drivers/devfreq/devfreq.c +++ b/drivers/devfreq/devfreq.c @@ -190,6 +190,31 @@ static struct devfreq_governor *find_devfreq_governor(const char *name) /* Load monitoring helper functions for governors use */ +static int update_devfreq_passive(struct devfreq *devfreq, unsigned long freq) +{ + struct devfreq *passive; + unsigned long rate; + int ret; + + list_for_each_entry(passive, &devfreq->passive_dev_list, passive_node) { + if (!passive->governor) + continue; + rate = freq; + + ret = passive->governor->get_target_freq(passive, &rate); + if (ret) + return ret; + + ret = passive->profile->target(passive->dev.parent, &rate, 0); + if (ret) + return ret; + + passive->previous_freq = rate; + } + + return 0; +} + /** * update_devfreq() - Reevaluate the device and configure frequency. * @devfreq: the devfreq instance. @@ -233,10 +258,18 @@ int update_devfreq(struct devfreq *devfreq) flags |= DEVFREQ_FLAG_LEAST_UPPER_BOUND; /* Use LUB */ } + if (!list_empty(&devfreq->passive_dev_list) + && devfreq->previous_freq > freq) + update_devfreq_passive(devfreq, freq); + err = devfreq->profile->target(devfreq->dev.parent, &freq, flags); if (err) return err; + if (!list_empty(&devfreq->passive_dev_list) + && devfreq->previous_freq < freq) + update_devfreq_passive(devfreq, freq); + if (devfreq->profile->freq_table) if (devfreq_update_status(devfreq, freq)) dev_err(&devfreq->dev, @@ -442,6 +475,10 @@ static void _remove_devfreq(struct devfreq *devfreq) return; } list_del(&devfreq->node); + list_del(&devfreq->passive_node); + if (!list_empty(&devfreq->passive_dev_list)) + list_del_init(&devfreq->passive_dev_list); + mutex_unlock(&devfreq_list_lock); if (devfreq->governor) @@ -559,6 +596,16 @@ struct devfreq *devfreq_add_device(struct device *dev, goto err_init; } + if (!strncmp(devfreq->governor_name, "passive", 7)) { + struct devfreq *parent_devfreq = + ((struct devfreq_passive_data *)data)->parent; + + list_add(&devfreq->passive_node, + &parent_devfreq->passive_dev_list); + } else { + INIT_LIST_HEAD(&devfreq->passive_dev_list); + } + return devfreq; err_init: diff --git a/drivers/devfreq/governor_passive.c b/drivers/devfreq/governor_passive.c new file mode 100644 index 000000000000..7443ae4b92f9 --- /dev/null +++ b/drivers/devfreq/governor_passive.c @@ -0,0 +1,108 @@ +/* + * linux/drivers/devfreq/governor_passive.c + * + * Copyright (C) 2015 Samsung Electronics + * Author: Chanwoo Choi + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + */ + +#include +#include +#include +#include +#include "governor.h" + +static int devfreq_passive_get_target_freq(struct devfreq *passive, + unsigned long *freq) +{ + struct devfreq_passive_data *passive_data = passive->data; + struct devfreq *parent_devfreq = passive_data->parent; + unsigned long child_freq = ULONG_MAX; + int i, count; + + /* + * Each devfreq has the OPP table. After deciding the new frequency + * from the governor of parent devfreq device, the passive governor + * need to get the index of new frequency on OPP table of parent + * device. And then the index is used for getting the suitable + * new frequency for passive devfreq device. + */ + + if (!passive->profile || !passive->profile->freq_table + || passive->profile->max_state <= 0) + return -EINVAL; + + /* + * When new frequency is lower than previous frequency of parent + * devfreq device, passive governor get the correct frequency from OPP + * list of parent device. Because in this case, *freq is temporary + * value which is decided by ondemand governor. + */ + if (parent_devfreq->previous_freq > *freq) { + struct dev_pm_opp *opp; + opp = devfreq_recommended_opp(parent_devfreq->dev.parent, + freq, 0); + if (IS_ERR_OR_NULL(opp)) + return PTR_ERR(opp); + } + + /* + * Get the OPP table's index of decided freqeuncy by governor + * of parent device. + */ + for (i = 0; i < parent_devfreq->profile->max_state; i++) + if (parent_devfreq->profile->freq_table[i] == *freq) + break; + + if (i == parent_devfreq->profile->max_state) + return -EINVAL; + count = passive->profile->max_state; + + /* Get the suitable frequency by using index of parent device. */ + if (i < passive->profile->max_state) + child_freq = passive->profile->freq_table[i]; + else + child_freq = passive->profile->freq_table[count - 1]; + + /* Return the suitable frequency for passive device. */ + *freq = child_freq; + + return 0; +} + +static int devfreq_passive_event_handler(struct devfreq *devfreq, + unsigned int event, void *data) +{ + return 0; +} + +static struct devfreq_governor devfreq_passive = { + .name = "passive", + .get_target_freq = devfreq_passive_get_target_freq, + .event_handler = devfreq_passive_event_handler, +}; + +static int __init devfreq_passive_init(void) +{ + return devfreq_add_governor(&devfreq_passive); +} +subsys_initcall(devfreq_passive_init); + +static void __exit devfreq_passive_exit(void) +{ + int ret; + + ret = devfreq_remove_governor(&devfreq_passive); + if (ret) + pr_err("%s: failed remove governor %d\n", __func__, ret); + + return; +} +module_exit(devfreq_passive_exit); + +MODULE_AUTHOR("Chanwoo Choi "); +MODULE_DESCRIPTION("DEVFREQ Passive governor"); +MODULE_LICENSE("GPL v2"); diff --git a/include/linux/devfreq.h b/include/linux/devfreq.h index 6fa02a20eb63..f7a6e6bd716e 100644 --- a/include/linux/devfreq.h +++ b/include/linux/devfreq.h @@ -177,6 +177,9 @@ struct devfreq { unsigned int *trans_table; unsigned long *time_in_state; unsigned long last_stat_updated; + + struct list_head passive_dev_list; + struct list_head passive_node; }; #if defined(CONFIG_PM_DEVFREQ) @@ -241,6 +244,20 @@ struct devfreq_simple_ondemand_data { }; #endif +#if IS_ENABLED(CONFIG_DEVFREQ_GOV_PASSIVE) +/** + * struct devfreq_passive_data - void *data fed to struct devfreq + * and devfreq_add_device + * @parent: The parent devfreq device. + * + * If the fed devfreq_passive_data pointer is NULL to the governor, + * the governor return ERROR. + */ +struct devfreq_passive_data { + struct devfreq *parent; +}; +#endif + #else /* !CONFIG_PM_DEVFREQ */ static inline struct devfreq *devfreq_add_device(struct device *dev, struct devfreq_dev_profile *profile,