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=-15.2 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_1 autolearn=ham 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 0BF07C56201 for ; Thu, 19 Nov 2020 17:22:50 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id A59552469D for ; Thu, 19 Nov 2020 17:22:49 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729033AbgKSRWs (ORCPT ); Thu, 19 Nov 2020 12:22:48 -0500 Received: from mail.kernel.org ([198.145.29.99]:39302 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728551AbgKSRWs (ORCPT ); Thu, 19 Nov 2020 12:22:48 -0500 Received: from gaia (unknown [2.26.170.190]) (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 4EEB42468B; Thu, 19 Nov 2020 17:22:46 +0000 (UTC) Date: Thu, 19 Nov 2020 17:22:43 +0000 From: Catalin Marinas To: Suzuki K Poulose Cc: linux-arm-kernel@lists.infradead.org, mathieu.poirier@linaro.org, mike.leach@linaro.org, linux-kernel@vger.kernel.org, anshuman.khandual@arm.com, jonathan.zhouwen@huawei.com, coresight@lists.linaro.org, Will Deacon Subject: Re: [PATCH v4 25/25] coresight: Add support for v8.4 SelfHosted tracing Message-ID: <20201119172243.GF4376@gaia> References: <20201119164547.2982871-1-suzuki.poulose@arm.com> <20201119164547.2982871-26-suzuki.poulose@arm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20201119164547.2982871-26-suzuki.poulose@arm.com> User-Agent: Mutt/1.10.1 (2018-07-13) Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Nov 19, 2020 at 04:45:47PM +0000, Suzuki K Poulose wrote: > From: Jonathan Zhou > > v8.4 tracing extensions added support for trace filtering controlled > by TRFCR_ELx. This must be programmed to allow tracing at EL1/EL2 and > EL0. The timestamp used is the virtual time. Also enable CONTEXIDR_EL2 > tracing if we are running the kernel at EL2. > > Cc: Catalin Marinas > Cc: Mathieu Poirier > Cc: Mike Leach > Cc: Will Deacon > Signed-off-by: Jonathan Zhou > [ Move the trace filtering setup etm_init_arch_data() and > clean ups] > Signed-off-by: Suzuki K Poulose > --- > .../coresight/coresight-etm4x-core.c | 25 +++++++++++++++++++ > 1 file changed, 25 insertions(+) > > diff --git a/drivers/hwtracing/coresight/coresight-etm4x-core.c b/drivers/hwtracing/coresight/coresight-etm4x-core.c > index 1d054d2ab2a0..647685736134 100644 > --- a/drivers/hwtracing/coresight/coresight-etm4x-core.c > +++ b/drivers/hwtracing/coresight/coresight-etm4x-core.c > @@ -760,6 +760,30 @@ static bool etm4_init_csdev_access(struct etmv4_drvdata *drvdata, > return false; > } > > +static void cpu_enable_tracing(void) > +{ > + u64 dfr0 = read_sysreg(id_aa64dfr0_el1); > + u64 trfcr; > + > + if (!(dfr0 >> ID_AA64DFR0_TRACE_FILT_SHIFT)) > + return; What if we get a new field at position 44 while the FILT one at 40 is 0? We should use cpuid_feature_extract_field() here. BTW, can this function not go in the cpufeature.c code? -- Catalin