From patchwork Mon Aug 17 22:23:40 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Liao, Bard" X-Patchwork-Id: 251389 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=-16.2 required=3.0 tests=BAYES_00, DATE_IN_PAST_06_12, DKIM_SIGNED, DKIM_VALID, HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH, MAILING_LIST_MULTI, MENTIONS_GIT_HOSTING, SIGNED_OFF_BY, SPF_HELO_NONE, SPF_PASS, URIBL_BLOCKED, USER_AGENT_GIT autolearn=unavailable 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 9F6BDC433DF for ; Tue, 18 Aug 2020 10:18:36 +0000 (UTC) Received: from alsa0.perex.cz (alsa0.perex.cz [77.48.224.243]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 25A17204EA for ; Tue, 18 Aug 2020 10:18:36 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=alsa-project.org header.i=@alsa-project.org header.b="S14l7V9A" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 25A17204EA Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=linux.intel.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=alsa-devel-bounces@alsa-project.org Received: from alsa1.perex.cz (alsa1.perex.cz [207.180.221.201]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by alsa0.perex.cz (Postfix) with ESMTPS id 853FA1746; Tue, 18 Aug 2020 12:17:44 +0200 (CEST) DKIM-Filter: OpenDKIM Filter v2.11.0 alsa0.perex.cz 853FA1746 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=alsa-project.org; s=default; t=1597745914; bh=/B+ZgAMOGbYrJxlTwPuV/DiIw03rkYhzSMnDNseyKqE=; h=From:To:Subject:Date:Cc:List-Id:List-Unsubscribe:List-Archive: List-Post:List-Help:List-Subscribe:From; b=S14l7V9AocxPkOawO2TwahZEcL0PnlrWmCJ8cYntyAZBsFyynR62O37pGHXqwty97 yEmaIOUi4QGJUBl1QWwi3V94piFuWKCZcuEuSak+QNbceBlz5nq4B0AozhoGXVd2p6 3eGF632ZwbuC9kIKaghhHdS5UkZpm65KWsjhm6pU= Received: from alsa1.perex.cz (localhost.localdomain [127.0.0.1]) by alsa1.perex.cz (Postfix) with ESMTP id 0741EF80228; Tue, 18 Aug 2020 12:17:44 +0200 (CEST) Received: by alsa1.perex.cz (Postfix, from userid 50401) id DF331F8023F; Tue, 18 Aug 2020 12:17:42 +0200 (CEST) Received: from mga09.intel.com (mga09.intel.com [134.134.136.24]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by alsa1.perex.cz (Postfix) with ESMTPS id 80B94F80114 for ; Tue, 18 Aug 2020 12:17:35 +0200 (CEST) DKIM-Filter: OpenDKIM Filter v2.11.0 alsa1.perex.cz 80B94F80114 IronPort-SDR: nOp44wt1aLcMFUmYjmxCL5KnwcYF6MRtxkEDrLbeB1931TrD6uUWQbf39zActkKDMCy3VrcPGK l6twNCixLejg== X-IronPort-AV: E=McAfee;i="6000,8403,9716"; a="155956194" X-IronPort-AV: E=Sophos;i="5.76,327,1592895600"; d="scan'208";a="155956194" X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from fmsmga008.fm.intel.com ([10.253.24.58]) by orsmga102.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 18 Aug 2020 03:17:26 -0700 IronPort-SDR: +RQdUwcKd0WpF1MV50K77ipSbXSpGk4l5pWDUHQoibQeSGg/cDyEdDflEAxvBYD4/wd4LIkt6S d0ZiwUUXD3Xg== X-IronPort-AV: E=Sophos;i="5.76,327,1592895600"; d="scan'208";a="279363998" Received: from bard-ubuntu.sh.intel.com ([10.239.13.33]) by fmsmga008-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 18 Aug 2020 03:17:22 -0700 From: Bard Liao To: alsa-devel@alsa-project.org, vkoul@kernel.org Subject: [PATCH] soundwire: cadence: fix race condition between suspend and Slave device alerts Date: Tue, 18 Aug 2020 06:23:40 +0800 Message-Id: <20200817222340.18042-1-yung-chuan.liao@linux.intel.com> X-Mailer: git-send-email 2.17.1 Cc: pierre-louis.bossart@linux.intel.com, vinod.koul@linaro.org, tiwai@suse.de, gregkh@linuxfoundation.org, linux-kernel@vger.kernel.org, ranjani.sridharan@linux.intel.com, hui.wang@canonical.com, broonie@kernel.org, srinivas.kandagatla@linaro.org, jank@cadence.com, mengdong.lin@intel.com, sanyog.r.kale@intel.com, rander.wang@linux.intel.com, bard.liao@intel.com X-BeenThere: alsa-devel@alsa-project.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: "Alsa-devel mailing list for ALSA developers - http://www.alsa-project.org" List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: alsa-devel-bounces@alsa-project.org Sender: "Alsa-devel" From: Pierre-Louis Bossart In system suspend stress cases, the SOF CI reports timeouts. The root cause is that an alert is generated while the system suspends. The interrupt handling generates transactions on the bus that will never be handled because the interrupts are disabled in parallel. As a result, the transaction never completes and times out on resume. This error doesn't seem too problematic since it happens in a work queue, and the system recovers without issues. Nevertheless, this race condition should not happen. When doing a system suspend, or when disabling interrupts, we should make sure the current transaction can complete, and prevent new work from being queued. BugLink: https://github.com/thesofproject/linux/issues/2344 Signed-off-by: Pierre-Louis Bossart Reviewed-by: Ranjani Sridharan Reviewed-by: Rander Wang Signed-off-by: Bard Liao --- drivers/soundwire/cadence_master.c | 24 +++++++++++++++++++++++- drivers/soundwire/cadence_master.h | 1 + 2 files changed, 24 insertions(+), 1 deletion(-) diff --git a/drivers/soundwire/cadence_master.c b/drivers/soundwire/cadence_master.c index 24eafe0aa1c3..1330ffc47596 100644 --- a/drivers/soundwire/cadence_master.c +++ b/drivers/soundwire/cadence_master.c @@ -791,7 +791,16 @@ irqreturn_t sdw_cdns_irq(int irq, void *dev_id) CDNS_MCP_INT_SLAVE_MASK, 0); int_status &= ~CDNS_MCP_INT_SLAVE_MASK; - schedule_work(&cdns->work); + + /* + * Deal with possible race condition between interrupt + * handling and disabling interrupts on suspend. + * + * If the master is in the process of disabling + * interrupts, don't schedule a workqueue + */ + if (cdns->interrupt_enabled) + schedule_work(&cdns->work); } cdns_writel(cdns, CDNS_MCP_INTSTAT, int_status); @@ -924,6 +933,19 @@ int sdw_cdns_enable_interrupt(struct sdw_cdns *cdns, bool state) slave_state = cdns_readl(cdns, CDNS_MCP_SLAVE_INTSTAT1); cdns_writel(cdns, CDNS_MCP_SLAVE_INTSTAT1, slave_state); } + cdns->interrupt_enabled = state; + + /* + * Complete any on-going status updates before updating masks, + * and cancel queued status updates. + * + * There could be a race with a new interrupt thrown before + * the 3 mask updates below are complete, so in the interrupt + * we use the 'interrupt_enabled' status to prevent new work + * from being queued. + */ + if (!state) + cancel_work_sync(&cdns->work); cdns_writel(cdns, CDNS_MCP_SLAVE_INTMASK0, slave_intmask0); cdns_writel(cdns, CDNS_MCP_SLAVE_INTMASK1, slave_intmask1); diff --git a/drivers/soundwire/cadence_master.h b/drivers/soundwire/cadence_master.h index fdec62b912d3..4d1aab5b5ec2 100644 --- a/drivers/soundwire/cadence_master.h +++ b/drivers/soundwire/cadence_master.h @@ -133,6 +133,7 @@ struct sdw_cdns { bool link_up; unsigned int msg_count; + bool interrupt_enabled; struct work_struct work;