From nobody Wed Apr 8 04:39:43 2026 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 345D6C32772 for ; Tue, 23 Aug 2022 18:02:56 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233273AbiHWSCx (ORCPT ); Tue, 23 Aug 2022 14:02:53 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:55104 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229530AbiHWSBC (ORCPT ); Tue, 23 Aug 2022 14:01:02 -0400 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id AD5DADCFCA; Tue, 23 Aug 2022 09:07:10 -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 BB94411FB; Tue, 23 Aug 2022 09:07:13 -0700 (PDT) Received: from e121896.arm.com (unknown [10.57.14.228]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPA id DE3553F718; Tue, 23 Aug 2022 09:07:07 -0700 (PDT) From: James Clark To: suzuki.poulose@arm.com, coresight@lists.linaro.org, mathieu.poirier@linaro.org Cc: mike.leach@linaro.org, leo.yan@linaro.org, linux-kernel@vger.kernel.org, german.gomez@arm.com, James Clark , Jonathan Corbet , Catalin Marinas , Will Deacon , Alexander Shishkin , linux-arm-kernel@lists.infradead.org, linux-doc@vger.kernel.org Subject: [PATCH v3 1/2] coresight: etm4x: Expose default timestamp source in sysfs Date: Tue, 23 Aug 2022 17:06:49 +0100 Message-Id: <20220823160650.455823-2-james.clark@arm.com> X-Mailer: git-send-email 2.28.0 In-Reply-To: <20220823160650.455823-1-james.clark@arm.com> References: <20220823160650.455823-1-james.clark@arm.com> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" From: German Gomez Add a new sysfs interface in /sys/bus/coresight/devices/etm/ts_source indicating the configured timestamp source when the ETM device driver was probed. The perf tool will use this information to detect if the trace data timestamp matches the kernel time, enabling correlation of CoreSight trace with perf events. Suggested-by: Suzuki K Poulose Signed-off-by: German Gomez Reviewed-by: Leo Yan Signed-off-by: James Clark --- arch/arm64/include/asm/sysreg.h | 1 + .../coresight/coresight-etm4x-sysfs.c | 29 +++++++++++++++++++ 2 files changed, 30 insertions(+) diff --git a/arch/arm64/include/asm/sysreg.h b/arch/arm64/include/asm/sysre= g.h index 7c71358d44c4..7a518a011669 100644 --- a/arch/arm64/include/asm/sysreg.h +++ b/arch/arm64/include/asm/sysreg.h @@ -1021,6 +1021,7 @@ #define SYS_MPIDR_SAFE_VAL (BIT(31)) =20 #define TRFCR_ELx_TS_SHIFT 5 +#define TRFCR_ELx_TS_MASK ((0x3UL) << TRFCR_ELx_TS_SHIFT) #define TRFCR_ELx_TS_VIRTUAL ((0x1UL) << TRFCR_ELx_TS_SHIFT) #define TRFCR_ELx_TS_GUEST_PHYSICAL ((0x2UL) << TRFCR_ELx_TS_SHIFT) #define TRFCR_ELx_TS_PHYSICAL ((0x3UL) << TRFCR_ELx_TS_SHIFT) diff --git a/drivers/hwtracing/coresight/coresight-etm4x-sysfs.c b/drivers/= hwtracing/coresight/coresight-etm4x-sysfs.c index 6ea8181816fc..9cac848cffaf 100644 --- a/drivers/hwtracing/coresight/coresight-etm4x-sysfs.c +++ b/drivers/hwtracing/coresight/coresight-etm4x-sysfs.c @@ -2306,6 +2306,34 @@ static ssize_t cpu_show(struct device *dev, } static DEVICE_ATTR_RO(cpu); =20 +static ssize_t ts_source_show(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + int val; + struct etmv4_drvdata *drvdata =3D dev_get_drvdata(dev->parent); + + if (!drvdata->trfcr) { + val =3D -1; + goto out; + } + + switch (drvdata->trfcr & TRFCR_ELx_TS_MASK) { + case TRFCR_ELx_TS_VIRTUAL: + case TRFCR_ELx_TS_GUEST_PHYSICAL: + case TRFCR_ELx_TS_PHYSICAL: + val =3D FIELD_GET(TRFCR_ELx_TS_MASK, drvdata->trfcr); + break; + default: + val =3D -1; + break; + } + +out: + return sysfs_emit(buf, "%d\n", val); +} +static DEVICE_ATTR_RO(ts_source); + static struct attribute *coresight_etmv4_attrs[] =3D { &dev_attr_nr_pe_cmp.attr, &dev_attr_nr_addr_cmp.attr, @@ -2360,6 +2388,7 @@ static struct attribute *coresight_etmv4_attrs[] =3D { &dev_attr_vmid_val.attr, &dev_attr_vmid_masks.attr, &dev_attr_cpu.attr, + &dev_attr_ts_source.attr, NULL, }; =20 --=20 2.28.0 From nobody Wed Apr 8 04:39:43 2026 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 D0C1FC32772 for ; Tue, 23 Aug 2022 18:03:02 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233399AbiHWSDA (ORCPT ); Tue, 23 Aug 2022 14:03:00 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:55108 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231183AbiHWSBE (ORCPT ); Tue, 23 Aug 2022 14:01:04 -0400 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id 12250DCFE8; Tue, 23 Aug 2022 09:07:13 -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 876A21424; Tue, 23 Aug 2022 09:07:16 -0700 (PDT) Received: from e121896.arm.com (unknown [10.57.14.228]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPA id B00BE3F718; Tue, 23 Aug 2022 09:07:10 -0700 (PDT) From: James Clark To: suzuki.poulose@arm.com, coresight@lists.linaro.org, mathieu.poirier@linaro.org Cc: mike.leach@linaro.org, leo.yan@linaro.org, linux-kernel@vger.kernel.org, german.gomez@arm.com, James Clark , Jonathan Corbet , Catalin Marinas , Will Deacon , Alexander Shishkin , linux-arm-kernel@lists.infradead.org, linux-doc@vger.kernel.org Subject: [PATCH v3 2/2] coresight: etm4x: docs: Add documentation for 'ts_source' sysfs interface Date: Tue, 23 Aug 2022 17:06:50 +0100 Message-Id: <20220823160650.455823-3-james.clark@arm.com> X-Mailer: git-send-email 2.28.0 In-Reply-To: <20220823160650.455823-1-james.clark@arm.com> References: <20220823160650.455823-1-james.clark@arm.com> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" From: German Gomez Sync sysfs documentation pages to include the new ts_source (timestamp source) interface. Signed-off-by: German Gomez Signed-off-by: James Clark --- .../ABI/testing/sysfs-bus-coresight-devices-etm4x | 8 ++++++++ .../trace/coresight/coresight-etm4x-reference.rst | 14 ++++++++++++++ 2 files changed, 22 insertions(+) diff --git a/Documentation/ABI/testing/sysfs-bus-coresight-devices-etm4x b/= Documentation/ABI/testing/sysfs-bus-coresight-devices-etm4x index 8e53a32f8150..08b1964f27d3 100644 --- a/Documentation/ABI/testing/sysfs-bus-coresight-devices-etm4x +++ b/Documentation/ABI/testing/sysfs-bus-coresight-devices-etm4x @@ -516,3 +516,11 @@ Contact: Mathieu Poirier Description: (Read) Returns the number of special conditional P1 right-han= d keys that the trace unit can use (0x194). The value is taken directly from the HW. + +What: /sys/bus/coresight/devices/etm/ts_source +Date: October 2022 +KernelVersion: 6.1 +Contact: Mathieu Poirier or Suzuki K Poulose = +Description: (Read) When FEAT_TRF is implemented, value of TRFCR_ELx.TS us= ed for + trace session. Otherwise -1 indicates an unknown time source. Check + trcidr0.tssize to see if a global timestamp is available. diff --git a/Documentation/trace/coresight/coresight-etm4x-reference.rst b/= Documentation/trace/coresight/coresight-etm4x-reference.rst index fb7578fd9372..70e34b8c81c1 100644 --- a/Documentation/trace/coresight/coresight-etm4x-reference.rst +++ b/Documentation/trace/coresight/coresight-etm4x-reference.rst @@ -71,6 +71,20 @@ =20 ---- =20 +:File: ``ts_source`` (ro) +:Trace Registers: None. +:Notes: + When FEAT_TRF is implemented, value of TRFCR_ELx.TS used for trace ses= sion. Otherwise -1 + indicates an unknown time source. Check trcidr0.tssize to see if a glo= bal timestamp is + available. + +:Example: + ``$> cat ts_source`` + + ``$> 1`` + +---- + :File: ``addr_idx`` (rw) :Trace Registers: None. :Notes: --=20 2.28.0