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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id C6902C46467 for ; Tue, 10 Jan 2023 09:31:16 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235313AbjAJJbO (ORCPT ); Tue, 10 Jan 2023 04:31:14 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:43228 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231489AbjAJJbC (ORCPT ); Tue, 10 Jan 2023 04:31:02 -0500 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id EE54B6471 for ; Tue, 10 Jan 2023 01:30:59 -0800 (PST) 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 D4C452F4; Tue, 10 Jan 2023 01:31:40 -0800 (PST) Received: from [10.57.37.155] (unknown [10.57.37.155]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id A66583F587; Tue, 10 Jan 2023 01:30:57 -0800 (PST) Message-ID: Date: Tue, 10 Jan 2023 09:30:56 +0000 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:102.0) Gecko/20100101 Thunderbird/102.4.2 Subject: Re: [PATCH] coresight: tmc-etr: Don't enable ETR when it's not ready Content-Language: en-US To: Yabin Cui Cc: coresight@lists.linaro.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, Mathieu Poirier , Suzuki K Poulose , Mike Leach , Leo Yan References: <20230109234312.2870846-1-yabinc@google.com> From: James Clark In-Reply-To: <20230109234312.2870846-1-yabinc@google.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 09/01/2023 23:43, Yabin Cui wrote: > Otherwise, it may cause error in AXI bus and result in a kernel panic. Hi Yabin, Thanks for the fix. Do you have a reproducer for this or some more info? For example is it a regression or has it always been there? And on which platform. Thanks James > > Signed-off-by: Yabin Cui > --- > .../hwtracing/coresight/coresight-tmc-core.c | 4 +++- > .../hwtracing/coresight/coresight-tmc-etr.c | 18 +++++++++++++++--- > drivers/hwtracing/coresight/coresight-tmc.h | 2 +- > 3 files changed, 19 insertions(+), 5 deletions(-) > > diff --git a/drivers/hwtracing/coresight/coresight-tmc-core.c b/drivers/hwtracing/coresight/coresight-tmc-core.c > index 07abf28ad725..c106d142e632 100644 > --- a/drivers/hwtracing/coresight/coresight-tmc-core.c > +++ b/drivers/hwtracing/coresight/coresight-tmc-core.c > @@ -31,7 +31,7 @@ DEFINE_CORESIGHT_DEVLIST(etb_devs, "tmc_etb"); > DEFINE_CORESIGHT_DEVLIST(etf_devs, "tmc_etf"); > DEFINE_CORESIGHT_DEVLIST(etr_devs, "tmc_etr"); > > -void tmc_wait_for_tmcready(struct tmc_drvdata *drvdata) > +int tmc_wait_for_tmcready(struct tmc_drvdata *drvdata) > { > struct coresight_device *csdev = drvdata->csdev; > struct csdev_access *csa = &csdev->access; > @@ -40,7 +40,9 @@ void tmc_wait_for_tmcready(struct tmc_drvdata *drvdata) > if (coresight_timeout(csa, TMC_STS, TMC_STS_TMCREADY_BIT, 1)) { > dev_err(&csdev->dev, > "timeout while waiting for TMC to be Ready\n"); > + return -EBUSY; > } > + return 0; > } > > void tmc_flush_and_stop(struct tmc_drvdata *drvdata) > diff --git a/drivers/hwtracing/coresight/coresight-tmc-etr.c b/drivers/hwtracing/coresight/coresight-tmc-etr.c > index 867ad8bb9b0c..2da99dd41ed6 100644 > --- a/drivers/hwtracing/coresight/coresight-tmc-etr.c > +++ b/drivers/hwtracing/coresight/coresight-tmc-etr.c > @@ -983,15 +983,21 @@ static void tmc_sync_etr_buf(struct tmc_drvdata *drvdata) > etr_buf->ops->sync(etr_buf, rrp, rwp); > } > > -static void __tmc_etr_enable_hw(struct tmc_drvdata *drvdata) > +static int __tmc_etr_enable_hw(struct tmc_drvdata *drvdata) > { > u32 axictl, sts; > struct etr_buf *etr_buf = drvdata->etr_buf; > + int rc = 0; > > CS_UNLOCK(drvdata->base); > > /* Wait for TMCSReady bit to be set */ > - tmc_wait_for_tmcready(drvdata); > + rc = tmc_wait_for_tmcready(drvdata); > + if (rc) { > + dev_err(&drvdata->csdev->dev, "not ready ETR isn't enabled\n"); > + CS_LOCK(drvdata->base); > + return rc; > + } > > writel_relaxed(etr_buf->size / 4, drvdata->base + TMC_RSZ); > writel_relaxed(TMC_MODE_CIRCULAR_BUFFER, drvdata->base + TMC_MODE); > @@ -1032,6 +1038,7 @@ static void __tmc_etr_enable_hw(struct tmc_drvdata *drvdata) > tmc_enable_hw(drvdata); > > CS_LOCK(drvdata->base); > + return rc; > } > > static int tmc_etr_enable_hw(struct tmc_drvdata *drvdata, > @@ -1060,7 +1067,12 @@ static int tmc_etr_enable_hw(struct tmc_drvdata *drvdata, > rc = coresight_claim_device(drvdata->csdev); > if (!rc) { > drvdata->etr_buf = etr_buf; > - __tmc_etr_enable_hw(drvdata); > + rc = __tmc_etr_enable_hw(drvdata); > + if (rc) { > + drvdata->etr_buf = NULL; > + coresight_disclaim_device(drvdata->csdev); > + tmc_etr_disable_catu(drvdata); > + } > } > > return rc; > diff --git a/drivers/hwtracing/coresight/coresight-tmc.h b/drivers/hwtracing/coresight/coresight-tmc.h > index 66959557cf39..01c0382a29c0 100644 > --- a/drivers/hwtracing/coresight/coresight-tmc.h > +++ b/drivers/hwtracing/coresight/coresight-tmc.h > @@ -255,7 +255,7 @@ struct tmc_sg_table { > }; > > /* Generic functions */ > -void tmc_wait_for_tmcready(struct tmc_drvdata *drvdata); > +int tmc_wait_for_tmcready(struct tmc_drvdata *drvdata); > void tmc_flush_and_stop(struct tmc_drvdata *drvdata); > void tmc_enable_hw(struct tmc_drvdata *drvdata); > void tmc_disable_hw(struct tmc_drvdata *drvdata);