From patchwork Thu Sep 21 03:36:29 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Anshuman Khandual X-Patchwork-Id: 13393625 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 8DEEECD4942 for ; Thu, 21 Sep 2023 03:37:18 +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=4Uh8rqlBUsg7idzvyaSDPP2N8mm41VB8UdF5nyJLmQY=; b=s6qNLVDPImYwyq AEBbm8tXrZT/4ID7vxRtNmFKbjR2GPILXXllfSY3K561gzfw6MKQUFmXDPau7TPRPbjTdKSAfBUuj t6wiXJEsfc0LtuJ5NZPh0tKy1QOmGGOgNxMNHEjRqWoLiSHyKfIslozus6uOZfLc2DKXKJydGqASZ QhAJstTdoqhLJLNJ59631eM/bO/qlcF/3V+6HBupp4d+BUj1x4VjsQO596XTJz9iHpdos+OVSaBqB s4V16u2RDXD0LYg5HihoPMaIcsLHfmosBIIyyrmsDJN3dim2p7M7WB/ov1I1Yc5HB1H1LQRiICAFk PTdAu3Thte2H67UVYssA==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.96 #2 (Red Hat Linux)) id 1qjAUp-004veq-0A; Thu, 21 Sep 2023 03:36:55 +0000 Received: from foss.arm.com ([217.140.110.172]) by bombadil.infradead.org with esmtp (Exim 4.96 #2 (Red Hat Linux)) id 1qjAUi-004vd8-1K for linux-arm-kernel@lists.infradead.org; Thu, 21 Sep 2023 03:36:50 +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 E0CE1C15; Wed, 20 Sep 2023 20:37:21 -0700 (PDT) Received: from a077893.arm.com (unknown [10.163.32.120]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPA id DBFA83F59C; Wed, 20 Sep 2023 20:36:40 -0700 (PDT) From: Anshuman Khandual To: linux-arm-kernel@lists.infradead.org, suzuki.poulose@arm.com Cc: Anshuman Khandual , Catalin Marinas , Will Deacon , Mike Leach , James Clark , Leo Yan , Jonathan Corbet , linux-doc@vger.kernel.org, coresight@lists.linaro.org, linux-kernel@vger.kernel.org Subject: [PATCH V7 1/3] coresight: etm: Override TRCIDR3.CCITMIN on errata affected cpus Date: Thu, 21 Sep 2023 09:06:29 +0530 Message-Id: <20230921033631.1298723-2-anshuman.khandual@arm.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20230921033631.1298723-1-anshuman.khandual@arm.com> References: <20230921033631.1298723-1-anshuman.khandual@arm.com> MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20230920_203648_545965_0EA89707 X-CRM114-Status: GOOD ( 16.48 ) 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 This work arounds errata 1490853 on Cortex-A76, and Neoverse-N1, errata 1491015 on Cortex-A77, errata 1502854 on Cortex-X1, and errata 1619801 on Neoverse-V1, based affected cpus, where software read for TRCIDR3.CCITMIN field in ETM gets an wrong value. If software uses the value returned by the TRCIDR3.CCITMIN register field, then it will limit the range which could be used for programming the ETM. In reality, the ETM could be programmed with a much smaller value than what is indicated by the TRCIDR3.CCITMIN field and still function correctly. If software reads the TRCIDR3.CCITMIN register field, corresponding to the instruction trace counting minimum threshold, observe the value 0x100 or a minimum cycle count threshold of 256. The correct value should be 0x4 or a minimum cycle count threshold of 4. This work arounds the problem via storing 4 in drvdata->ccitmin on affected systems where the TRCIDR3.CCITMIN has been 256, thus preserving cycle count threshold granularity. These errata information has been updated in arch/arm64/silicon-errata.rst, but without their corresponding configs because these have been implemented directly in the driver. Cc: Catalin Marinas Cc: Will Deacon Cc: Suzuki K Poulose Cc: Mike Leach Cc: James Clark Cc: Jonathan Corbet Cc: linux-doc@vger.kernel.org Cc: coresight@lists.linaro.org Cc: linux-arm-kernel@lists.infradead.org Cc: linux-kernel@vger.kernel.org Reviewed-by: Mike Leach Signed-off-by: Anshuman Khandual --- Documentation/arch/arm64/silicon-errata.rst | 10 +++++ .../coresight/coresight-etm4x-core.c | 37 +++++++++++++++++++ 2 files changed, 47 insertions(+) diff --git a/Documentation/arch/arm64/silicon-errata.rst b/Documentation/arch/arm64/silicon-errata.rst index e96f057ea2a0..8f1be5da68b7 100644 --- a/Documentation/arch/arm64/silicon-errata.rst +++ b/Documentation/arch/arm64/silicon-errata.rst @@ -115,6 +115,10 @@ stable kernels. +----------------+-----------------+-----------------+-----------------------------+ | ARM | Cortex-A76 | #1463225 | ARM64_ERRATUM_1463225 | +----------------+-----------------+-----------------+-----------------------------+ +| ARM | Cortex-A76 | #1490853 | N/A | ++----------------+-----------------+-----------------+-----------------------------+ +| ARM | Cortex-A77 | #1491015 | N/A | ++----------------+-----------------+-----------------+-----------------------------+ | ARM | Cortex-A77 | #1508412 | ARM64_ERRATUM_1508412 | +----------------+-----------------+-----------------+-----------------------------+ | ARM | Cortex-A710 | #2119858 | ARM64_ERRATUM_2119858 | @@ -125,6 +129,8 @@ stable kernels. +----------------+-----------------+-----------------+-----------------------------+ | ARM | Cortex-A715 | #2645198 | ARM64_ERRATUM_2645198 | +----------------+-----------------+-----------------+-----------------------------+ +| ARM | Cortex-X1 | #1502854 | N/A | ++----------------+-----------------+-----------------+-----------------------------+ | ARM | Cortex-X2 | #2119858 | ARM64_ERRATUM_2119858 | +----------------+-----------------+-----------------+-----------------------------+ | ARM | Cortex-X2 | #2224489 | ARM64_ERRATUM_2224489 | @@ -133,6 +139,8 @@ stable kernels. +----------------+-----------------+-----------------+-----------------------------+ | ARM | Neoverse-N1 | #1349291 | N/A | +----------------+-----------------+-----------------+-----------------------------+ +| ARM | Neoverse-N1 | #1490853 | N/A | ++----------------+-----------------+-----------------+-----------------------------+ | ARM | Neoverse-N1 | #1542419 | ARM64_ERRATUM_1542419 | +----------------+-----------------+-----------------+-----------------------------+ | ARM | Neoverse-N2 | #2139208 | ARM64_ERRATUM_2139208 | @@ -141,6 +149,8 @@ stable kernels. +----------------+-----------------+-----------------+-----------------------------+ | ARM | Neoverse-N2 | #2253138 | ARM64_ERRATUM_2253138 | +----------------+-----------------+-----------------+-----------------------------+ +| ARM | Neoverse-V1 | #1619801 | N/A | ++----------------+-----------------+-----------------+-----------------------------+ | ARM | MMU-500 | #841119,826419 | N/A | +----------------+-----------------+-----------------+-----------------------------+ | ARM | MMU-600 | #1076982,1209401| N/A | diff --git a/drivers/hwtracing/coresight/coresight-etm4x-core.c b/drivers/hwtracing/coresight/coresight-etm4x-core.c index 77b0271ce6eb..9619d9d0bbb1 100644 --- a/drivers/hwtracing/coresight/coresight-etm4x-core.c +++ b/drivers/hwtracing/coresight/coresight-etm4x-core.c @@ -1150,6 +1150,41 @@ static void cpu_detect_trace_filtering(struct etmv4_drvdata *drvdata) drvdata->trfcr = trfcr; } +/* + * The following errata on applicable cpu ranges, affect the CCITMIN filed + * in TCRIDR3 register. Software read for the field returns 0x100 limiting + * the cycle threshold granularity, whereas the right value should have + * been 0x4, which is well supported in the hardware. + */ +static struct midr_range etm_wrong_ccitmin_cpus[] = { + /* Erratum #1490853 - Cortex-A76 */ + MIDR_RANGE(MIDR_CORTEX_A76, 0, 0, 4, 0), + /* Erratum #1490853 - Neoverse-N1 */ + MIDR_RANGE(MIDR_NEOVERSE_N1, 0, 0, 4, 0), + /* Erratum #1491015 - Cortex-A77 */ + MIDR_RANGE(MIDR_CORTEX_A77, 0, 0, 1, 0), + /* Erratum #1502854 - Cortex-X1 */ + MIDR_REV(MIDR_CORTEX_X1, 0, 0), + /* Erratum #1619801 - Neoverse-V1 */ + MIDR_REV(MIDR_NEOVERSE_V1, 0, 0), + {}, +}; + +static void etm4_fixup_wrong_ccitmin(struct etmv4_drvdata *drvdata) +{ + /* + * Erratum affected cpus will read 256 as the minimum + * instruction trace cycle counting threshold whereas + * the correct value should be 4 instead. Override the + * recorded value for 'drvdata->ccitmin' to workaround + * this problem. + */ + if (is_midr_in_range_list(read_cpuid_id(), etm_wrong_ccitmin_cpus)) { + if (drvdata->ccitmin == 256) + drvdata->ccitmin = 4; + } +} + static void etm4_init_arch_data(void *info) { u32 etmidr0; @@ -1214,6 +1249,8 @@ static void etm4_init_arch_data(void *info) etmidr3 = etm4x_relaxed_read32(csa, TRCIDR3); /* CCITMIN, bits[11:0] minimum threshold value that can be programmed */ drvdata->ccitmin = FIELD_GET(TRCIDR3_CCITMIN_MASK, etmidr3); + etm4_fixup_wrong_ccitmin(drvdata); + /* EXLEVEL_S, bits[19:16] Secure state instruction tracing */ drvdata->s_ex_level = FIELD_GET(TRCIDR3_EXLEVEL_S_MASK, etmidr3); drvdata->config.s_ex_level = drvdata->s_ex_level; From patchwork Thu Sep 21 03:36:30 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Anshuman Khandual X-Patchwork-Id: 13393626 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 02977CD4942 for ; Thu, 21 Sep 2023 03:37:22 +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=ujA3cb8V9m8uGR456ZWnu2eKDJKIYVJkPfWXvbvUzFc=; b=nUF+tWC+dEEkTq KXhGVlwrqbTIEJ12KK+xi1kbl3lwrJ4pWrwLJBcufGWyOwFgkPN9NOylvRhmKYVCV9uhFBG4/kAYM u0gBzW9FC+/Nm+Xpwzz6ecOnypRtP7S0ADLHiv0Pr8umGOBJUAPzNEUgZh3RLwBB2t5jitW0+9wix bAxxqFHXsKLa0/yRxEipDtcNxPbnH/lJl8IWSKsYN13hFv84p0OUgwUV6CCgWWjkxsPAsRScUnshb WWoNDwopHG/y/pXdDwtObHUuNIhmuIfNIse9urLjaRdT3mPuSMX+uq/R6RIRgnfN1hci71cOb4khP B84AHFeGV373avxeeGIA==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.96 #2 (Red Hat Linux)) id 1qjAUp-004vfD-1r; Thu, 21 Sep 2023 03:36:55 +0000 Received: from foss.arm.com ([217.140.110.172]) by bombadil.infradead.org with esmtp (Exim 4.96 #2 (Red Hat Linux)) id 1qjAUl-004veC-29 for linux-arm-kernel@lists.infradead.org; Thu, 21 Sep 2023 03:36:53 +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 765C5DA7; Wed, 20 Sep 2023 20:37:26 -0700 (PDT) Received: from a077893.arm.com (unknown [10.163.32.120]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPA id 5C6CA3F59C; Wed, 20 Sep 2023 20:36:45 -0700 (PDT) From: Anshuman Khandual To: linux-arm-kernel@lists.infradead.org, suzuki.poulose@arm.com Cc: Anshuman Khandual , Catalin Marinas , Will Deacon , Mike Leach , James Clark , Leo Yan , Jonathan Corbet , linux-doc@vger.kernel.org, coresight@lists.linaro.org, linux-kernel@vger.kernel.org Subject: [PATCH V7 2/3] coresight: etm: Make cycle count threshold user configurable Date: Thu, 21 Sep 2023 09:06:30 +0530 Message-Id: <20230921033631.1298723-3-anshuman.khandual@arm.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20230921033631.1298723-1-anshuman.khandual@arm.com> References: <20230921033631.1298723-1-anshuman.khandual@arm.com> MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20230920_203651_797033_45F0C0F7 X-CRM114-Status: GOOD ( 14.06 ) 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 When cycle counting is enabled, we use a default threshold value i.e 0x100 for the instruction trace cycle counting. This patch makes the cycle threshold user configurable via perf event attributes( 'cc_threshold' => event->attr.config3[11:0] ), falling back to the current default if unspecified. Cc: Suzuki K Poulose Cc: Mike Leach Cc: James Clark Cc: Leo Yan Cc: coresight@lists.linaro.org Cc: linux-arm-kernel@lists.infradead.org Cc: linux-doc@vger.kernel.org Cc: linux-kernel@vger.kernel.org Reviewed-by: Mike Leach Signed-off-by: Anshuman Khandual --- drivers/hwtracing/coresight/coresight-etm-perf.c | 2 ++ drivers/hwtracing/coresight/coresight-etm4x-core.c | 9 +++++++-- 2 files changed, 9 insertions(+), 2 deletions(-) diff --git a/drivers/hwtracing/coresight/coresight-etm-perf.c b/drivers/hwtracing/coresight/coresight-etm-perf.c index 5ca6278baff4..09f75dffae60 100644 --- a/drivers/hwtracing/coresight/coresight-etm-perf.c +++ b/drivers/hwtracing/coresight/coresight-etm-perf.c @@ -68,6 +68,7 @@ PMU_FORMAT_ATTR(preset, "config:0-3"); PMU_FORMAT_ATTR(sinkid, "config2:0-31"); /* config ID - set if a system configuration is selected */ PMU_FORMAT_ATTR(configid, "config2:32-63"); +PMU_FORMAT_ATTR(cc_threshold, "config3:0-11"); /* @@ -101,6 +102,7 @@ static struct attribute *etm_config_formats_attr[] = { &format_attr_preset.attr, &format_attr_configid.attr, &format_attr_branch_broadcast.attr, + &format_attr_cc_threshold.attr, NULL, }; diff --git a/drivers/hwtracing/coresight/coresight-etm4x-core.c b/drivers/hwtracing/coresight/coresight-etm4x-core.c index 9619d9d0bbb1..5b6a878a2ac5 100644 --- a/drivers/hwtracing/coresight/coresight-etm4x-core.c +++ b/drivers/hwtracing/coresight/coresight-etm4x-core.c @@ -644,7 +644,7 @@ static int etm4_parse_event_config(struct coresight_device *csdev, struct etmv4_config *config = &drvdata->config; struct perf_event_attr *attr = &event->attr; unsigned long cfg_hash; - int preset; + int preset, cc_threshold; /* Clear configuration from previous run */ memset(config, 0, sizeof(struct etmv4_config)); @@ -667,7 +667,12 @@ static int etm4_parse_event_config(struct coresight_device *csdev, if (attr->config & BIT(ETM_OPT_CYCACC)) { config->cfg |= TRCCONFIGR_CCI; /* TRM: Must program this for cycacc to work */ - config->ccctlr = ETM_CYC_THRESHOLD_DEFAULT; + cc_threshold = attr->config3 & ETM_CYC_THRESHOLD_MASK; + if (!cc_threshold) + cc_threshold = ETM_CYC_THRESHOLD_DEFAULT; + if (cc_threshold < drvdata->ccitmin) + cc_threshold = drvdata->ccitmin; + config->ccctlr = cc_threshold; } if (attr->config & BIT(ETM_OPT_TS)) { /* From patchwork Thu Sep 21 03:36:31 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Anshuman Khandual X-Patchwork-Id: 13393627 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 7864FCD4942 for ; Thu, 21 Sep 2023 03:37:29 +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; 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Wed, 20 Sep 2023 20:36:49 -0700 (PDT) From: Anshuman Khandual To: linux-arm-kernel@lists.infradead.org, suzuki.poulose@arm.com Cc: Anshuman Khandual , Catalin Marinas , Will Deacon , Mike Leach , James Clark , Leo Yan , Jonathan Corbet , linux-doc@vger.kernel.org, coresight@lists.linaro.org, linux-kernel@vger.kernel.org Subject: [PATCH V7 3/3] Documentation: coresight: Add cc_threshold tunable Date: Thu, 21 Sep 2023 09:06:31 +0530 Message-Id: <20230921033631.1298723-4-anshuman.khandual@arm.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20230921033631.1298723-1-anshuman.khandual@arm.com> References: <20230921033631.1298723-1-anshuman.khandual@arm.com> MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20230920_203656_326251_C7FF151A X-CRM114-Status: GOOD ( 10.81 ) 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 This updates config option to include 'cc_threshold' tunable value. Cc: Suzuki K Poulose Cc: Mike Leach Cc: James Clark Cc: Jonathan Corbet Cc: coresight@lists.linaro.org Cc: linux-arm-kernel@lists.infradead.org Cc: linux-doc@vger.kernel.org Cc: linux-kernel@vger.kernel.org Reviewed by: Mike Leach Signed-off-by: Anshuman Khandual --- Documentation/trace/coresight/coresight.rst | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/Documentation/trace/coresight/coresight.rst b/Documentation/trace/coresight/coresight.rst index 4a71ea6cb390..ce55adb80b82 100644 --- a/Documentation/trace/coresight/coresight.rst +++ b/Documentation/trace/coresight/coresight.rst @@ -624,6 +624,10 @@ They are also listed in the folder /sys/bus/event_source/devices/cs_etm/format/ * - timestamp - Session local version of the system wide setting: :ref:`ETMv4_MODE_TIMESTAMP ` + * - cc_threshold + - Cycle count threshold value. If nothing is provided here or the provided value is 0, then the + default value i.e 0x100 will be used. If provided value is less than minimum cycles threshold + value, as indicated via TRCIDR3.CCITMIN, then the minimum value will be used instead. How to use the STM module -------------------------