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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 47EF0EE644C for ; Fri, 15 Sep 2023 09:37:23 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233761AbjIOJh0 (ORCPT ); Fri, 15 Sep 2023 05:37:26 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:54396 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233746AbjIOJhV (ORCPT ); Fri, 15 Sep 2023 05:37:21 -0400 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id 885CA171C; Fri, 15 Sep 2023 02:37:15 -0700 (PDT) Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 593541FB; Fri, 15 Sep 2023 02:37:52 -0700 (PDT) Received: from a077893.arm.com (unknown [10.163.62.147]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPA id 7B65B3F67D; Fri, 15 Sep 2023 02:37:11 -0700 (PDT) From: Anshuman Khandual To: linux-arm-kernel@lists.infradead.org, suzuki.poulose@arm.com Cc: Anshuman Khandual , Catalin Marinas , Will Deacon , Mike Leach , James Clark , Leo Yan , Jonathan Corbet , linux-doc@vger.kernel.org, coresight@lists.linaro.org, linux-kernel@vger.kernel.org Subject: [PATCH V5 - RESEND 2/3] coresight: etm: Make cycle count threshold user configurable Date: Fri, 15 Sep 2023 15:06:48 +0530 Message-Id: <20230915093649.435163-3-anshuman.khandual@arm.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20230915093649.435163-1-anshuman.khandual@arm.com> References: <20230915093649.435163-1-anshuman.khandual@arm.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Cycle counting is enabled, when requested and supported but with a default threshold value ETM_CYC_THRESHOLD_DEFAULT i.e 0x100 getting into TRCCCCTLR, representing the minimum interval between cycle count trace packets. This makes cycle threshold user configurable, from the user space via perf event attributes. Although it falls back using ETM_CYC_THRESHOLD_DEFAULT, in case no explicit request. As expected it creates a sysfs file as well. /sys/bus/event_source/devices/cs_etm/format/cc_threshold New 'cc_threshold' uses 'event->attr.config3' as no more space is available in 'event->attr.config1' or 'event->attr.config2'. Cc: Suzuki K Poulose Cc: Mike Leach Cc: James Clark Cc: Leo Yan Cc: coresight@lists.linaro.org Cc: linux-arm-kernel@lists.infradead.org Cc: linux-doc@vger.kernel.org Cc: linux-kernel@vger.kernel.org Reviewed-by: Mike Leach Signed-off-by: Anshuman Khandual --- drivers/hwtracing/coresight/coresight-etm-perf.c | 2 ++ drivers/hwtracing/coresight/coresight-etm4x-core.c | 9 +++++++-- 2 files changed, 9 insertions(+), 2 deletions(-) diff --git a/drivers/hwtracing/coresight/coresight-etm-perf.c b/drivers/hwtracing/coresight/coresight-etm-perf.c index 5ca6278baff4..09f75dffae60 100644 --- a/drivers/hwtracing/coresight/coresight-etm-perf.c +++ b/drivers/hwtracing/coresight/coresight-etm-perf.c @@ -68,6 +68,7 @@ PMU_FORMAT_ATTR(preset, "config:0-3"); PMU_FORMAT_ATTR(sinkid, "config2:0-31"); /* config ID - set if a system configuration is selected */ PMU_FORMAT_ATTR(configid, "config2:32-63"); +PMU_FORMAT_ATTR(cc_threshold, "config3:0-11"); /* @@ -101,6 +102,7 @@ static struct attribute *etm_config_formats_attr[] = { &format_attr_preset.attr, &format_attr_configid.attr, &format_attr_branch_broadcast.attr, + &format_attr_cc_threshold.attr, NULL, }; diff --git a/drivers/hwtracing/coresight/coresight-etm4x-core.c b/drivers/hwtracing/coresight/coresight-etm4x-core.c index c01455bb1caf..044aed25979b 100644 --- a/drivers/hwtracing/coresight/coresight-etm4x-core.c +++ b/drivers/hwtracing/coresight/coresight-etm4x-core.c @@ -644,7 +644,7 @@ static int etm4_parse_event_config(struct coresight_device *csdev, struct etmv4_config *config = &drvdata->config; struct perf_event_attr *attr = &event->attr; unsigned long cfg_hash; - int preset; + int preset, cc_threshold; /* Clear configuration from previous run */ memset(config, 0, sizeof(struct etmv4_config)); @@ -667,7 +667,12 @@ static int etm4_parse_event_config(struct coresight_device *csdev, if (attr->config & BIT(ETM_OPT_CYCACC)) { config->cfg |= TRCCONFIGR_CCI; /* TRM: Must program this for cycacc to work */ - config->ccctlr = ETM_CYC_THRESHOLD_DEFAULT; + cc_threshold = attr->config3 & ETM_CYC_THRESHOLD_MASK; + if (!cc_threshold) + cc_threshold = ETM_CYC_THRESHOLD_DEFAULT; + if (cc_threshold < drvdata->ccitmin) + cc_threshold = drvdata->ccitmin; + config->ccctlr = cc_threshold; } if (attr->config & BIT(ETM_OPT_TS)) { /* -- 2.25.1