From patchwork Wed Jul 24 12:38:46 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Leonard Crestez X-Patchwork-Id: 11056785 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 7791E746 for ; Wed, 24 Jul 2019 12:39:15 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 64A9728803 for ; Wed, 24 Jul 2019 12:39:15 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 55DDC28817; Wed, 24 Jul 2019 12:39:15 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-5.2 required=2.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,MAILING_LIST_MULTI,RCVD_IN_DNSWL_MED autolearn=unavailable version=3.3.1 Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id D33C528803 for ; Wed, 24 Jul 2019 12:39:14 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20170209; h=Sender: Content-Transfer-Encoding:Content-Type:MIME-Version:Cc:List-Subscribe: List-Help:List-Post:List-Archive:List-Unsubscribe:List-Id:References: In-Reply-To:Message-Id:Date:Subject:To:From:Reply-To:Content-ID: Content-Description:Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc :Resent-Message-ID:List-Owner; bh=kJ/bykAuXUlJbI3bdJjR1eD7IwARC8on1+mGN2wMTpc=; b=kOPUbXUQaC0bBrEwRL5z8QfdMw CN3zPdCyyp8YDZgUvIFZ1CM9uAjasxZRpsB1DqruaqUipJASVUmRQzkJ0MF3VaWsvx/uoUayv9RUE Wnneggxc8ZTID57XUsmPwRsA+ZKCPl4sbbNAU3aioa3HfDNduFpDQoABty9cbDUv4DrnRmy4lBwvD EkGPRSRGbnZ6LWvzSypDKbHwVPZrVtFM5V9SaoDX+doVR5qEDRifh0TDwZzmkQF+eY+DvEdVhLRa1 7nbLXstJGQs8PGlGNDB6reEQQ5Og1gFxlxDLoenRe9o+Wkebg5TlBouuV1V7XdwjejdCCNQky9n1F gIZNW0YA==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.92 #3 (Red Hat Linux)) id 1hqGXz-0002bJ-98; Wed, 24 Jul 2019 12:39:07 +0000 Received: from inva020.nxp.com ([92.121.34.13]) by bombadil.infradead.org with esmtps (Exim 4.92 #3 (Red Hat Linux)) id 1hqGXn-0002Pw-Ua for linux-arm-kernel@lists.infradead.org; Wed, 24 Jul 2019 12:38:57 +0000 Received: from inva020.nxp.com (localhost [127.0.0.1]) by inva020.eu-rdc02.nxp.com (Postfix) with ESMTP id C01931A030E; Wed, 24 Jul 2019 14:38:54 +0200 (CEST) Received: from inva024.eu-rdc02.nxp.com (inva024.eu-rdc02.nxp.com [134.27.226.22]) by inva020.eu-rdc02.nxp.com (Postfix) with ESMTP id B22D81A02F9; Wed, 24 Jul 2019 14:38:54 +0200 (CEST) Received: from fsr-ub1864-112.ea.freescale.net (fsr-ub1864-112.ea.freescale.net [10.171.82.98]) by inva024.eu-rdc02.nxp.com (Postfix) with ESMTP id AFBA8205D8; Wed, 24 Jul 2019 14:38:53 +0200 (CEST) From: Leonard Crestez To: MyungJoo Ham , Kyungmin Park , Will Deacon , Stephen Boyd Subject: [RFCv3 3/3] PM / devfreq: Add imx perf event support Date: Wed, 24 Jul 2019 15:38:46 +0300 Message-Id: <72c89cd93817faf450ecd2d6e1d9c273198ff9ab.1563971855.git.leonard.crestez@nxp.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: References: In-Reply-To: References: X-Virus-Scanned: ClamAV using ClamSMTP X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20190724_053856_259577_520EC096 X-CRM114-Status: GOOD ( 16.16 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Dong Aisheng , Mark Rutland , Fabio Estevam , Sascha Hauer , Jacky Bai , Anson Huang , linux-pm@vger.kernel.org, Viresh Kumar , Michael Turquette , Frank Li , NXP Linux Team , linux-kernel@vger.kernel.org, Chanwoo Choi , devicetree@vger.kernel.org, Rob Herring , Alexandre Bailon , Pengutronix Kernel Team , Shawn Guo , Georgi Djakov , linux-arm-kernel@lists.infradead.org, Abel Vesa MIME-Version: 1.0 Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org X-Virus-Scanned: ClamAV using ClamSMTP The imx8m ddrc has a performance monitoring block attached which can be used to measure bandwidth usage automatically adjust frequency. There is already a perf driver for that block so instead of implementing a devfreq events driver use the in-kernel perf API to fetch read/write bandwidth values and sum them. Signed-off-by: Leonard Crestez --- drivers/devfreq/imx-devfreq.c | 135 ++++++++++++++++++++++++++++++++++ 1 file changed, 135 insertions(+) diff --git a/drivers/devfreq/imx-devfreq.c b/drivers/devfreq/imx-devfreq.c index 3ee2d37883c6..fd4c8ffb8b4a 100644 --- a/drivers/devfreq/imx-devfreq.c +++ b/drivers/devfreq/imx-devfreq.c @@ -11,14 +11,28 @@ #include #include #include #include +#include +#include + struct imx_devfreq { struct devfreq_dev_profile profile; struct devfreq *devfreq; struct clk *clk; + + struct platform_device* pmu_pdev; + struct pmu *pmu; + + struct perf_event_attr rd_event_attr; + struct perf_event_attr wr_event_attr; + struct perf_event *rd_event; + struct perf_event *wr_event; + + u64 last_rd_val, last_rd_ena, last_rd_run; + u64 last_wr_val, last_wr_ena, last_wr_run; }; static int imx_devfreq_target(struct device *dev, unsigned long *freq, u32 flags) { struct imx_devfreq *priv = dev_get_drvdata(dev); @@ -64,22 +78,131 @@ static int imx_devfreq_get_dev_status(struct device *dev, stat->busy_time = 0; stat->total_time = 0; stat->current_frequency = clk_get_rate(priv->clk); + if (priv->rd_event && priv->wr_event) { + u64 rd_delta, rd_val, rd_ena, rd_run; + u64 wr_delta, wr_val, wr_ena, wr_run; + + rd_val = perf_event_read_value(priv->rd_event, &rd_ena, &rd_run); + wr_val = perf_event_read_value(priv->wr_event, &wr_ena, &wr_run); + + rd_delta = (rd_val - priv->last_rd_val) * (rd_ena - priv->last_rd_ena) / (rd_run - priv->last_rd_run); + priv->last_rd_val = rd_val; + priv->last_rd_ena = rd_ena; + priv->last_rd_run = rd_run; + wr_delta = (wr_val - priv->last_wr_val) * (wr_ena - priv->last_wr_ena) / (wr_run - priv->last_wr_run); + priv->last_wr_val = wr_val; + priv->last_wr_ena = wr_ena; + priv->last_wr_run = wr_run; + + /* magic numbers, possibly wrong */ + stat->busy_time = 4 * (rd_delta + wr_delta); + stat->total_time = stat->current_frequency; + + dev_dbg(dev, "perf load %02lu%% read=%lu write=%lu freq=%lu\n", + 100 * stat->busy_time / stat->total_time, + rd_delta, wr_delta, stat->current_frequency); + } + + return 0; +} + +static int imx_devfreq_perf_disable(struct imx_devfreq *priv) +{ + /* release and set to NULL */ + if (!IS_ERR_OR_NULL(priv->rd_event)) + perf_event_release_kernel(priv->rd_event); + if (!IS_ERR_OR_NULL(priv->wr_event)) + perf_event_release_kernel(priv->wr_event); + priv->rd_event = NULL; + priv->wr_event = NULL; + + return 0; +} + +static int imx_devfreq_perf_enable(struct imx_devfreq *priv) +{ + int ret; + + priv->rd_event_attr.size = sizeof(priv->rd_event_attr); + priv->rd_event_attr.type = priv->pmu->type; + priv->rd_event_attr.config = 0x2a; + + priv->rd_event = perf_event_create_kernel_counter( + &priv->rd_event_attr, 0, NULL, NULL, NULL); + if (IS_ERR(priv->rd_event)) { + ret = PTR_ERR(priv->rd_event); + goto err; + } + + priv->wr_event_attr.size = sizeof(priv->wr_event_attr); + priv->wr_event_attr.type = priv->pmu->type; + priv->wr_event_attr.config = 0x2b; + + priv->wr_event = perf_event_create_kernel_counter( + &priv->wr_event_attr, 0, NULL, NULL, NULL); + if (IS_ERR(priv->wr_event)) { + ret = PTR_ERR(priv->wr_event); + goto err; + } + return 0; + +err: + imx_devfreq_perf_disable(priv); + return ret; +} + +static int imx_devfreq_init_events(struct device *dev, + struct device_node* events_node) +{ + struct imx_devfreq *priv = dev_get_drvdata(dev); + struct device_driver *driver; + + /* + * We need pmu->type for perf_event_attr but there is no API for + * mapping device_node to pmu. Fetch private data for imx-ddr-pmu and + * cast that to a struct pmu instead. + */ + priv->pmu_pdev = of_find_device_by_node(events_node); + if (!priv->pmu_pdev) + return -ENOENT; + driver = priv->pmu_pdev->dev.driver; + if (!driver) + return -ENOENT; + if (strcmp(driver->name, "imx-ddr-pmu")) { + dev_warn(dev, "devfreq-events node %pOF has unexpected driver %s\n", + events_node, driver->name); + return -ENODEV; + } + + priv->pmu = platform_get_drvdata(priv->pmu_pdev); + if (!priv->pmu) + return -EPROBE_DEFER; + + dev_info(dev, "events from pmu %s\n", priv->pmu->name); + + return imx_devfreq_perf_enable(priv); } static void imx_devfreq_exit(struct device *dev) { + struct imx_devfreq *priv = dev_get_drvdata(dev); + + imx_devfreq_perf_disable(priv); + platform_device_put(priv->pmu_pdev); + return dev_pm_opp_of_remove_table(dev); } static int imx_devfreq_probe(struct platform_device *pdev) { struct device *dev = &pdev->dev; struct imx_devfreq *priv; + struct device_node *events_node; const char *gov = DEVFREQ_GOV_USERSPACE; int ret; priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL); if (!priv) @@ -104,10 +227,20 @@ static int imx_devfreq_probe(struct platform_device *pdev) priv->profile.get_dev_status = imx_devfreq_get_dev_status; priv->profile.exit = imx_devfreq_exit; priv->profile.get_cur_freq = imx_devfreq_get_cur_freq; priv->profile.initial_freq = clk_get_rate(priv->clk); + /* Handle devfreq-events */ + events_node = of_parse_phandle(dev->of_node, "devfreq-events", 0); + if (events_node) { + ret = imx_devfreq_init_events(dev, events_node); + of_node_put(events_node); + if (ret) + goto err; + gov = DEVFREQ_GOV_SIMPLE_ONDEMAND; + } + priv->devfreq = devm_devfreq_add_device(dev, &priv->profile, gov, NULL); if (IS_ERR(priv->devfreq)) { ret = PTR_ERR(priv->devfreq); dev_err(dev, "failed to add devfreq device: %d\n", ret); @@ -115,10 +248,12 @@ static int imx_devfreq_probe(struct platform_device *pdev) } return 0; err: + imx_devfreq_perf_disable(priv); + platform_device_put(priv->pmu_pdev); dev_pm_opp_of_remove_table(dev); return ret; } static const struct of_device_id imx_devfreq_of_match[] = {