From mboxrd@z Thu Jan 1 00:00:00 1970 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=-8.5 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE, SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_1 autolearn=unavailable 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 B5CACC433DF for ; Wed, 20 May 2020 07:42:03 +0000 (UTC) Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 89C83207ED for ; Wed, 20 May 2020 07:42:03 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="o9AAeXFs"; dkim=fail reason="signature verification failed" (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="Ia0TwmQn" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 89C83207ED Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=kernel.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org 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:Cc:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:In-Reply-To:MIME-Version:References: Message-ID:Subject:To:From:Date:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=dN+P0dohF0Ymser+CDb+875ywQdkTV7hLwMb0pFcJiw=; b=o9AAeXFs0c+SxB aBnWqqyrZiOp8upGDEZQP4arBDXIUekbFO5N1RvFlHNl62oDdatYSgjjXYXHdYNx+A/6GgouGjSyl MOpik6i4CZzCTMuqKC/oQsRf5xtO+JuAPnNtkJCCfM1RVxo+bJ+eCnOoVw/2jfjDccv+Pr0PwYpUB goKvkq64dQWLSuvIzPqZW1On3Hom2QvcugSz/nzKY4ElaYxDCBj79VDBbrJ+JQQLsjeFOKnrWC8cF zfwdzBCVnsOVoqF4slxzs8WxQyVBGZA56jd3UzrmLw+Y3unOqHI9U50awwh9L3IsNzAW6V5uKnLfc B2GpNXTcU7fdzjDslSNw==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1jbJMZ-0000eK-6S; Wed, 20 May 2020 07:42:03 +0000 Received: from mail.kernel.org ([198.145.29.99]) by bombadil.infradead.org with esmtps (Exim 4.92.3 #3 (Red Hat Linux)) id 1jbJMV-0000bd-T5 for linux-arm-kernel@lists.infradead.org; Wed, 20 May 2020 07:42:01 +0000 Received: from willie-the-truck (236.31.169.217.in-addr.arpa [217.169.31.236]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id A0B8D207D3; Wed, 20 May 2020 07:41:57 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1589960519; bh=lF7qPacJPzgODON1dCxvm8X9ZeJrLrmX+CSPXciqLRk=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=Ia0TwmQnc6ZZdJmV24OWMsg7Vr8OSYGwWaXu49hX7APgJbDlXdtnE8XRmdPZjh+Td mFYmbVMbkVbN3pv+cP8dO4Et3zp18+lTpVb30ob/KP+nfQxSRhq06XtSKbJJr8Yi5M GeVUWLlfMFOIL0vYqmCLv4LzDGdHbWIH2bBizYf0= Date: Wed, 20 May 2020 08:41:54 +0100 From: Will Deacon To: Joakim Zhang Subject: Re: [PATCH V2 2/3] perf/imx_ddr: Add system PMU identifier for userspace Message-ID: <20200520074154.GA23818@willie-the-truck> References: <20200520025619.687-1-qiangqing.zhang@nxp.com> <20200520025619.687-3-qiangqing.zhang@nxp.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20200520025619.687-3-qiangqing.zhang@nxp.com> User-Agent: Mutt/1.10.1 (2018-07-13) X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20200520_004159_976550_F3FDB936 X-CRM114-Status: GOOD ( 17.93 ) 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: mark.rutland@arm.com, devicetree@vger.kernel.org, john.garry@huawei.com, linux-kernel@vger.kernel.org, robh+dt@kernel.org, linux-imx@nxp.com, shawnguo@kernel.org, linux-arm-kernel@lists.infradead.org Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Wed, May 20, 2020 at 10:56:18AM +0800, Joakim Zhang wrote: > The DDR Perf for i.MX8 is a system PMU whose axi id would different from > SoC to SoC. Need expose system PMU identifier for userspace which refer > to /sys/bus/event_source/devices//identifier. > > Signed-off-by: Joakim Zhang > --- > drivers/perf/fsl_imx8_ddr_perf.c | 29 +++++++++++++++++++++++++++++ > 1 file changed, 29 insertions(+) > > diff --git a/drivers/perf/fsl_imx8_ddr_perf.c b/drivers/perf/fsl_imx8_ddr_perf.c > index 90884d14f95f..ba523a94f4d7 100644 > --- a/drivers/perf/fsl_imx8_ddr_perf.c > +++ b/drivers/perf/fsl_imx8_ddr_perf.c > @@ -76,6 +76,7 @@ struct ddr_pmu { > unsigned int cpu; > struct hlist_node node; > struct device *dev; > + const char *identifier; > struct perf_event *events[NUM_COUNTERS]; > int active_events; > enum cpuhp_state cpuhp_state; > @@ -84,6 +85,27 @@ struct ddr_pmu { > int id; > }; > > +static ssize_t ddr_perf_identifier_show(struct device *dev, > + struct device_attribute *attr, > + char *page) > +{ > + struct ddr_pmu *pmu = dev_get_drvdata(dev); > + > + return sprintf(page, "%s\n", pmu->identifier); > +} > + > +static struct device_attribute ddr_perf_identifier_attr = > + __ATTR(identifier, 0444, ddr_perf_identifier_show, NULL); > + > +static struct attribute *ddr_perf_identifier_attrs[] = { > + &ddr_perf_identifier_attr.attr, > + NULL, > +}; > + > +static struct attribute_group ddr_perf_identifier_attr_group = { > + .attrs = ddr_perf_identifier_attrs, > +}; > + > enum ddr_perf_filter_capabilities { > PERF_CAP_AXI_ID_FILTER = 0, > PERF_CAP_AXI_ID_FILTER_ENHANCED, > @@ -237,6 +259,7 @@ static const struct attribute_group *attr_groups[] = { > &ddr_perf_format_attr_group, > &ddr_perf_cpumask_attr_group, > &ddr_perf_filter_cap_attr_group, > + &ddr_perf_identifier_attr_group, > NULL, > }; > > @@ -601,6 +624,7 @@ static int ddr_perf_probe(struct platform_device *pdev) > struct ddr_pmu *pmu; > struct device_node *np; > void __iomem *base; > + const char *identifier = NULL; > char *name; > int num; > int ret; > @@ -620,6 +644,11 @@ static int ddr_perf_probe(struct platform_device *pdev) > > platform_set_drvdata(pdev, pmu); > > + ret = of_property_read_string(np, "identifier", &identifier); > + if (ret < 0) > + dev_warn(&pdev->dev, "Failed to get identifier\n"); > + pmu->identifier = identifier; I think this is exactly what Rob was objecting to when he said "yet another way to identify the SoC from userspace". I've asked him on the other thread as to what the best way to do this is. Will _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel