From patchwork Sun Jan 10 22:48:44 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Suzuki K Poulose X-Patchwork-Id: 12009541 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=-17.0 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT 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 289C2C433DB for ; Sun, 10 Jan 2021 22:57:38 +0000 (UTC) Received: from merlin.infradead.org (merlin.infradead.org [205.233.59.134]) (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 A9723229CA for ; Sun, 10 Jan 2021 22:57:37 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org A9723229CA Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=arm.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+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=merlin.20170209; h=Sender:Content-Transfer-Encoding: Content-Type:Cc:List-Subscribe:List-Help:List-Post:List-Archive: List-Unsubscribe:List-Id:MIME-Version: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=Yomw7wKw+OMfSZ+4RBFSToCk2Y9H6XdLKgF8Cgo7K2A=; b=nS8YdHKR2RCgY9t1jNNpX82ax syDm84phFsZXRiHrT+QT7Ew6grDbgOkScbC5Tg1fVBqPWpcQUD28GeIxPcUgAX0EufiornD+4sFic iDBo3Lo7Y21/vEsugB2l3eCkGGyoK+c3qZ6zjtNW07toAvGv1SJBnZlBErZBGcAZ2IlaAdJWzSqL6 dhqej3hSPtbBcOacBxsJuT3wf8KG2q9AH3E6ieWX7DdzWaQkYCDUfCFnIgWb2b3lK8wWO6yIAWlNY Z0brmg3A6hejX2UVOcOAgOiS/GQpzs7HttiopzusEahsEFWYOFhGLWvn5zD2wvAtOR0sfA5r0ktaX AsSNVUbHQ==; Received: from localhost ([::1] helo=merlin.infradead.org) by merlin.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1kyjcR-0001aL-Jz; Sun, 10 Jan 2021 22:55:31 +0000 Received: from foss.arm.com ([217.140.110.172]) by merlin.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1kyjWj-0006wP-6S for linux-arm-kernel@lists.infradead.org; Sun, 10 Jan 2021 22:49:38 +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 83C8C152F; Sun, 10 Jan 2021 14:49:36 -0800 (PST) Received: from ewhatever.cambridge.arm.com (ewhatever.cambridge.arm.com [10.1.197.1]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPA id 34D733F719; Sun, 10 Jan 2021 14:49:35 -0800 (PST) From: Suzuki K Poulose To: linux-arm-kernel@lists.infradead.org Subject: [PATCH v7 22/28] coresight: etm4x: Detect system instructions support Date: Sun, 10 Jan 2021 22:48:44 +0000 Message-Id: <20210110224850.1880240-23-suzuki.poulose@arm.com> X-Mailer: git-send-email 2.24.1 In-Reply-To: <20210110224850.1880240-1-suzuki.poulose@arm.com> References: <20210110224850.1880240-1-suzuki.poulose@arm.com> MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20210110_174937_342151_9E194EBB X-CRM114-Status: GOOD ( 13.42 ) 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: mathieu.poirier@linaro.org, anshuman.khandual@arm.com, catalin.marinas@arm.com, coresight@lists.linaro.org, Suzuki K Poulose , linux-kernel@vger.kernel.org, leo.yan@linaro.org, jonathan.zhouwen@huawei.com, mike.leach@linaro.org Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org ETM v4.4 onwards adds support for system instruction access to the ETM. Detect the support on an ETM and switch to using the mode when available. Cc: Mike Leach Reviewed-by: Mathieu Poirier Signed-off-by: Suzuki K Poulose --- .../coresight/coresight-etm4x-core.c | 39 +++++++++++++++++++ 1 file changed, 39 insertions(+) diff --git a/drivers/hwtracing/coresight/coresight-etm4x-core.c b/drivers/hwtracing/coresight/coresight-etm4x-core.c index 3b17feb86d8a..6cbc6e0c0819 100644 --- a/drivers/hwtracing/coresight/coresight-etm4x-core.c +++ b/drivers/hwtracing/coresight/coresight-etm4x-core.c @@ -782,6 +782,37 @@ static const struct coresight_ops etm4_cs_ops = { .source_ops = &etm4_source_ops, }; +static inline bool cpu_supports_sysreg_trace(void) +{ + u64 dfr0 = read_sysreg_s(SYS_ID_AA64DFR0_EL1); + + return ((dfr0 >> ID_AA64DFR0_TRACEVER_SHIFT) & 0xfUL) > 0; +} + +static bool etm4_init_sysreg_access(struct etmv4_drvdata *drvdata, + struct csdev_access *csa) +{ + u32 devarch; + + if (!cpu_supports_sysreg_trace()) + return false; + + /* + * ETMs implementing sysreg access must implement TRCDEVARCH. + */ + devarch = read_etm4x_sysreg_const_offset(TRCDEVARCH); + if ((devarch & ETM_DEVARCH_ID_MASK) != ETM_DEVARCH_ETMv4x_ARCH) + return false; + *csa = (struct csdev_access) { + .io_mem = false, + .read = etm4x_sysreg_read, + .write = etm4x_sysreg_write, + }; + + drvdata->arch = etm_devarch_to_arch(devarch); + return true; +} + static bool etm4_init_iomem_access(struct etmv4_drvdata *drvdata, struct csdev_access *csa) { @@ -812,9 +843,17 @@ static bool etm4_init_iomem_access(struct etmv4_drvdata *drvdata, static bool etm4_init_csdev_access(struct etmv4_drvdata *drvdata, struct csdev_access *csa) { + /* + * Always choose the memory mapped io, if there is + * a memory map to prevent sysreg access on broken + * systems. + */ if (drvdata->base) return etm4_init_iomem_access(drvdata, csa); + if (etm4_init_sysreg_access(drvdata, csa)) + return true; + return false; }