From patchwork Thu Nov 19 16:45:42 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Suzuki K Poulose X-Patchwork-Id: 11918361 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=-16.8 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,URIBL_BLOCKED, 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 C4119C56201 for ; Thu, 19 Nov 2020 16:56:14 +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 3A66024199 for ; Thu, 19 Nov 2020 16:56:13 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="P+YWhTJH" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 3A66024199 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=4V6PC9cRhH0PzMYL9ZjRP9OshJxQYkVVL+67L1tqReI=; b=P+YWhTJHq7gSTHae9LJjwb+xC rF3+QvJA/FK7oQS+Ld+G4RTFUDUQ9Kbu/1GPITVtkN15j/z5Uj1T1Fz+av70c3ILRyQRmXFEmBJ3f qketbQWNBW6+rRRCWEeL0yToS1J4BHm9D6jsv2u3Be5E5pyRMoVycd83jbw8WyoNiLY6KQGZkZXg/ z5U7tvlT3U4HE3vjcU3lpNi+vuqsJziz+VLUkfKnnYz/xrEQn+sDVj4JZYq/gYFViJdF2dZMn0Xzk XnaOm6BDROtEAZZgrOzqO2VlzyZbHH1X2h44mJ0oeXcXd6VCp1gYWnw27Gh1KcR+WZ8Gpc+4AjkbL XiHrGBcDg==; Received: from localhost ([::1] helo=merlin.infradead.org) by merlin.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1kfnC1-00043Y-50; Thu, 19 Nov 2020 16:53:57 +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 1kfn4o-0000y9-91 for linux-arm-kernel@lists.infradead.org; Thu, 19 Nov 2020 16:46:50 +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 07284161B; Thu, 19 Nov 2020 08:46:30 -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 99C583F718; Thu, 19 Nov 2020 08:46:28 -0800 (PST) From: Suzuki K Poulose To: linux-arm-kernel@lists.infradead.org Subject: [PATCH v4 20/25] coresight: etm4x: Detect system instructions support Date: Thu, 19 Nov 2020 16:45:42 +0000 Message-Id: <20201119164547.2982871-21-suzuki.poulose@arm.com> X-Mailer: git-send-email 2.24.1 In-Reply-To: <20201119164547.2982871-1-suzuki.poulose@arm.com> References: <20201119164547.2982871-1-suzuki.poulose@arm.com> MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20201119_114630_548848_062A9544 X-CRM114-Status: GOOD ( 14.82 ) 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, coresight@lists.linaro.org, Suzuki K Poulose , linux-kernel@vger.kernel.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 7ac0a185c146..5cbea9c27f58 100644 --- a/drivers/hwtracing/coresight/coresight-etm4x-core.c +++ b/drivers/hwtracing/coresight/coresight-etm4x-core.c @@ -684,6 +684,37 @@ 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) { @@ -714,9 +745,17 @@ 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; }