From patchwork Thu May 14 10:59:15 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Sai Prakash Ranjan X-Patchwork-Id: 11548505 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id AF540912 for ; Thu, 14 May 2020 11:00:05 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 96B11206A5 for ; Thu, 14 May 2020 11:00:05 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (1024-bit key) header.d=mg.codeaurora.org header.i=@mg.codeaurora.org header.b="fhLnbSVT" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726037AbgENLAB (ORCPT ); Thu, 14 May 2020 07:00:01 -0400 Received: from mail26.static.mailgun.info ([104.130.122.26]:45980 "EHLO mail26.static.mailgun.info" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726050AbgENLAA (ORCPT ); Thu, 14 May 2020 07:00:00 -0400 DKIM-Signature: a=rsa-sha256; v=1; c=relaxed/relaxed; d=mg.codeaurora.org; q=dns/txt; s=smtp; t=1589453999; h=Content-Transfer-Encoding: MIME-Version: Message-Id: Date: Subject: Cc: To: From: Sender; bh=XXh5+LWOjvzZ2TuFCskcCvNUWMxUWX8AwU8p78yuh8Y=; b=fhLnbSVT9/1g1WxE3VE8Y7j4t31+1WpDv5C3mepIn4HcbT/7izBIlpbeSERY+B0LT/e6pMpm yN/UpjHUB1cNgU/sh5AV1b3pPGMi6pWMj039w/Az/HFMBNY80zQWn8Ieqzcc1gJi92OKSFsV +a1cWfQAPzXSUr77HlKUEEWuwVE= X-Mailgun-Sending-Ip: 104.130.122.26 X-Mailgun-Sid: WyI1MzIzYiIsICJsaW51eC1hcm0tbXNtQHZnZXIua2VybmVsLm9yZyIsICJiZTllNGEiXQ== Received: from smtp.codeaurora.org (ec2-35-166-182-171.us-west-2.compute.amazonaws.com [35.166.182.171]) by mxa.mailgun.org with ESMTP id 5ebd2492.7f33debd29d0-smtp-out-n02; Thu, 14 May 2020 10:59:30 -0000 (UTC) Received: by smtp.codeaurora.org (Postfix, from userid 1001) id 1857BC4478C; Thu, 14 May 2020 10:59:30 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-caf-mail-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-1.0 required=2.0 tests=ALL_TRUSTED,SPF_NONE, URIBL_BLOCKED autolearn=unavailable autolearn_force=no version=3.4.0 Received: from blr-ubuntu-311.qualcomm.com (blr-bdr-fw-01_GlobalNAT_AllZones-Outside.qualcomm.com [103.229.18.19]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-SHA256 (128/128 bits)) (No client certificate requested) (Authenticated sender: saiprakash.ranjan) by smtp.codeaurora.org (Postfix) with ESMTPSA id E0357C433BA; Thu, 14 May 2020 10:59:25 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 smtp.codeaurora.org E0357C433BA Authentication-Results: aws-us-west-2-caf-mail-1.web.codeaurora.org; dmarc=none (p=none dis=none) header.from=codeaurora.org Authentication-Results: aws-us-west-2-caf-mail-1.web.codeaurora.org; spf=none smtp.mailfrom=saiprakash.ranjan@codeaurora.org From: Sai Prakash Ranjan To: Mathieu Poirier , Suzuki K Poulose , Mike Leach Cc: Stephen Boyd , Leo Yan , linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, linux-arm-msm@vger.kernel.org, Tingwei Zhang , coresight@lists.linaro.org, Sai Prakash Ranjan Subject: [PATCH] coresight: etm4x: Add support to disable trace unit power up Date: Thu, 14 May 2020 16:29:15 +0530 Message-Id: <20200514105915.27516-1-saiprakash.ranjan@codeaurora.org> X-Mailer: git-send-email 2.22.0 MIME-Version: 1.0 Sender: linux-arm-msm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-arm-msm@vger.kernel.org From: Tingwei Zhang On some Qualcomm Technologies Inc. SoCs like SC7180, there exists a hardware errata where the APSS (Application Processor SubSystem)/CPU watchdog counter is stopped when ETM register TRCPDCR.PU=1. Since the ETMs share the same power domain as that of respective CPU cores, they are powered on when the CPU core is powered on. So we can disable powering up of the trace unit after checking for this errata via new property called "qcom,tupwr-disable". Signed-off-by: Tingwei Zhang Co-developed-by: Sai Prakash Ranjan Signed-off-by: Sai Prakash Ranjan Signed-off-by: Tingwei Zhang Signed-off-by: must always be that of the developer submitting the --- .../devicetree/bindings/arm/coresight.txt | 6 ++++ drivers/hwtracing/coresight/coresight-etm4x.c | 29 ++++++++++++------- 2 files changed, 25 insertions(+), 10 deletions(-) diff --git a/Documentation/devicetree/bindings/arm/coresight.txt b/Documentation/devicetree/bindings/arm/coresight.txt index 846f6daae71b..d2030128fe46 100644 --- a/Documentation/devicetree/bindings/arm/coresight.txt +++ b/Documentation/devicetree/bindings/arm/coresight.txt @@ -108,6 +108,12 @@ its hardware characteristcs. * arm,cp14: must be present if the system accesses ETM/PTM management registers via co-processor 14. + * qcom,tupwr-disable: boolean. Indicates that trace unit power up can + be disabled on Qualcomm Technologies Inc. systems where ETMs are in + the same power domain as their CPU cores. This property is required + to identify such systems with hardware errata where the CPU watchdog + counter is stopped when TRCPDCR.PU=1. + * Optional property for TMC: * arm,buffer-size: size of contiguous buffer space for TMC ETR diff --git a/drivers/hwtracing/coresight/coresight-etm4x.c b/drivers/hwtracing/coresight/coresight-etm4x.c index fb0f5f4f3a91..6886b44f6947 100644 --- a/drivers/hwtracing/coresight/coresight-etm4x.c +++ b/drivers/hwtracing/coresight/coresight-etm4x.c @@ -104,6 +104,11 @@ struct etm4_enable_arg { int rc; }; +static inline bool etm4_can_disable_tupwr(struct device *dev) +{ + return fwnode_property_present(dev_fwnode(dev), "qcom,tupwr-disable"); +} + static int etm4_enable_hw(struct etmv4_drvdata *drvdata) { int i, rc; @@ -196,12 +201,14 @@ static int etm4_enable_hw(struct etmv4_drvdata *drvdata) writel_relaxed(config->vmid_mask0, drvdata->base + TRCVMIDCCTLR0); writel_relaxed(config->vmid_mask1, drvdata->base + TRCVMIDCCTLR1); - /* - * Request to keep the trace unit powered and also - * emulation of powerdown - */ - writel_relaxed(readl_relaxed(drvdata->base + TRCPDCR) | TRCPDCR_PU, - drvdata->base + TRCPDCR); + if (!etm4_can_disable_tupwr(etm_dev)) { + /* + * Request to keep the trace unit powered and also + * emulation of powerdown + */ + writel_relaxed(readl_relaxed(drvdata->base + TRCPDCR) | TRCPDCR_PU, + drvdata->base + TRCPDCR); + } /* Enable the trace unit */ writel_relaxed(1, drvdata->base + TRCPRGCTLR); @@ -476,10 +483,12 @@ static void etm4_disable_hw(void *info) CS_UNLOCK(drvdata->base); - /* power can be removed from the trace unit now */ - control = readl_relaxed(drvdata->base + TRCPDCR); - control &= ~TRCPDCR_PU; - writel_relaxed(control, drvdata->base + TRCPDCR); + if (!etm4_can_disable_tupwr(etm_dev)) { + /* power can be removed from the trace unit now */ + control = readl_relaxed(drvdata->base + TRCPDCR); + control &= ~TRCPDCR_PU; + writel_relaxed(control, drvdata->base + TRCPDCR); + } control = readl_relaxed(drvdata->base + TRCPRGCTLR);