From patchwork Thu Jan 13 09:10:51 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: James Clark X-Patchwork-Id: 12712493 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 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 smtp.lore.kernel.org (Postfix) with ESMTPS id 9F9EDC433F5 for ; Thu, 13 Jan 2022 09:12:40 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:References:In-Reply-To: Message-Id:Date:Subject:Cc:To:From:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=4doMFnoH5dDoEFBibgySvh6NSffegDIj+x/QsmPghFM=; b=FvT/dqQjN4iqjo XK5S9b3A1t1d0SJduYsN9decQ4CfUwVCg1pev4gKlUOs1UVRDoyEPiO3IrpHTw7sDDYlUCxErki7F HwNZ0eqcIcISvHsTnTnK6QtYXE/CuEPSdFzbQhZPNHjKdR7VltG/bWM+CNrZOm45RPixvo93zoym6 fCPSLncyG/HlqAqZxT19eZgxkFXw9k3UhMJ6MwaZG5E+CESHuxnMhsDzGCWnlHERwOWM7ewiJOJeg LChnOharcUhe2L5PYWFs1kNg1aAZED46lasXczalIajQgFaClzoLr6Twf/KZeImnB3iiX6kT5Fh+U 6gpaUYdnUqPmYq11LzsQ==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1n7w8p-005CxX-EF; Thu, 13 Jan 2022 09:11:31 +0000 Received: from foss.arm.com ([217.140.110.172]) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1n7w8W-005Cq9-Q5 for linux-arm-kernel@lists.infradead.org; Thu, 13 Jan 2022 09:11:14 +0000 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 B61976D; Thu, 13 Jan 2022 01:11:11 -0800 (PST) Received: from e121896.arm.com (unknown [10.57.35.134]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPA id 317663F766; Thu, 13 Jan 2022 01:11:09 -0800 (PST) From: James Clark To: suzuki.poulose@arm.com, mathieu.poirier@linaro.org, coresight@lists.linaro.org, leo.yan@linaro.com, mike.leach@linaro.org Cc: James Clark , Leo Yan , John Garry , Will Deacon , Mark Rutland , Alexander Shishkin , Jiri Olsa , Namhyung Kim , linux-arm-kernel@lists.infradead.org, linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, linux-perf-users@vger.kernel.org Subject: [PATCH v2 2/6] coresight: Fail to open with return stacks if they are unavailable Date: Thu, 13 Jan 2022 09:10:51 +0000 Message-Id: <20220113091056.1297982-3-james.clark@arm.com> X-Mailer: git-send-email 2.28.0 In-Reply-To: <20220113091056.1297982-1-james.clark@arm.com> References: <20220113091056.1297982-1-james.clark@arm.com> MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20220113_011112_925892_5483ABF5 X-CRM114-Status: GOOD ( 13.18 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org Maintain consistency with the other options by failing to open when they aren't supported. For example ETM_OPT_TS, ETM_OPT_CTXTID2 and the newly added ETM_OPT_BRANCH_BROADCAST all return with -EINVAL if they are requested but not supported by hardware. The consequence of not doing this is that the user may not be aware that they are not enabling the feature as it is silently disabled. Signed-off-by: James Clark Reviewed-by: Mike Leach --- drivers/hwtracing/coresight/coresight-etm4x-core.c | 13 +++++++++---- 1 file changed, 9 insertions(+), 4 deletions(-) diff --git a/drivers/hwtracing/coresight/coresight-etm4x-core.c b/drivers/hwtracing/coresight/coresight-etm4x-core.c index 04669ecc0efa..a93c1a5fe045 100644 --- a/drivers/hwtracing/coresight/coresight-etm4x-core.c +++ b/drivers/hwtracing/coresight/coresight-etm4x-core.c @@ -674,10 +674,15 @@ static int etm4_parse_event_config(struct coresight_device *csdev, } /* return stack - enable if selected and supported */ - if ((attr->config & BIT(ETM_OPT_RETSTK)) && drvdata->retstack) - /* bit[12], Return stack enable bit */ - config->cfg |= BIT(12); - + if (attr->config & BIT(ETM_OPT_RETSTK)) { + if (!drvdata->retstack) { + ret = -EINVAL; + goto out; + } else { + /* bit[12], Return stack enable bit */ + config->cfg |= BIT(12); + } + } /* * Set any selected configuration and preset. *