From patchwork Thu Dec 1 13:48:45 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Richard Fitzgerald X-Patchwork-Id: 630682 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 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 smtp.lore.kernel.org (Postfix) with ESMTPS id 95433C4321E for ; Thu, 1 Dec 2022 13:52:03 +0000 (UTC) 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 BFD931751; Thu, 1 Dec 2022 14:51:11 +0100 (CET) DKIM-Filter: OpenDKIM Filter v2.11.0 alsa0.perex.cz BFD931751 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=alsa-project.org; s=default; t=1669902721; bh=JxJUnxqzgsfMCGKZZ0WlM9DObr8nm/UDJipTyPtkjh4=; h=From:To:Subject:Date:In-Reply-To:References:Cc:List-Id: List-Unsubscribe:List-Archive:List-Post:List-Help:List-Subscribe: From; b=uLtAdveIi836Zz2VD33rgRFaeNNMQnM35qMehv1RU+yvFuKukdq9Gk0Svtd6zXXx9 0EMt5ZG7webP1nw4iNOSk4BVEEyuBV1v3zTAFFLD0AUFCdnZVjdP8yMOm+PcSh3rSV roC17MO5IEwx0h7AQN9DBrvlutnWLLwl5TEdXhtk= Received: from alsa1.perex.cz (localhost.localdomain [127.0.0.1]) by alsa1.perex.cz (Postfix) with ESMTP id 1AA91F805C0; Thu, 1 Dec 2022 14:49:01 +0100 (CET) Received: by alsa1.perex.cz (Postfix, from userid 50401) id 16422F805BE; Thu, 1 Dec 2022 14:48:58 +0100 (CET) Received: from mx0b-001ae601.pphosted.com (mx0a-001ae601.pphosted.com [67.231.149.25]) (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 A6AA3F805B5 for ; Thu, 1 Dec 2022 14:48:51 +0100 (CET) DKIM-Filter: OpenDKIM Filter v2.11.0 alsa1.perex.cz A6AA3F805B5 Authentication-Results: alsa1.perex.cz; dkim=pass (2048-bit key) header.d=cirrus.com header.i=@cirrus.com header.b="iH+D/pvM" Received: from pps.filterd (m0077473.ppops.net [127.0.0.1]) by mx0a-001ae601.pphosted.com (8.17.1.19/8.17.1.19) with ESMTP id 2B15l1vB016609; Thu, 1 Dec 2022 07:48:50 -0600 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=cirrus.com; h=from : to : cc : subject : date : message-id : in-reply-to : references : mime-version : content-transfer-encoding : content-type; s=PODMain02222019; bh=O24ewM62YnyTshopgCFYg5eq7HQMvKb/cYKJclNcynE=; b=iH+D/pvM3F2HsdV3sbPIDmZMdTQM3pFHKpJq7eZLee9i/u69NRVObv1KHnylpXDx7ZW/ a5L/fxVSe+Y+kfarQfLMGjWxx9iBQS5Ecn2cV7K56rtxnXRJW+gZVGMkupk/uhGNYsLa Y/uT/3a8xeao+GGcs2AcKo5xUUKE19Csjn+SE3s8JxYCLevaOqeqcuvATznVKDyhTfge Qdy3VYF+3Ww7kS5JxfbIjCZi2OZ1eALVSI9F8xk7xed3OoCyz9bmBKDEwvOCmMGoIlgK xci/82cGnKqQXRrPWNynyJLv6+A/ijbd9xAb3cyJs/3fKXH6VwlYbzKDDHf8H1i9Zves WQ== Received: from ediex01.ad.cirrus.com ([84.19.233.68]) by mx0a-001ae601.pphosted.com (PPS) with ESMTPS id 3m6k75rhqm-2 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Thu, 01 Dec 2022 07:48:50 -0600 Received: from ediex01.ad.cirrus.com (198.61.84.80) by ediex01.ad.cirrus.com (198.61.84.80) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.1118.20; Thu, 1 Dec 2022 07:48:46 -0600 Received: from ediswmail.ad.cirrus.com (198.61.86.93) by ediex01.ad.cirrus.com (198.61.84.80) with Microsoft SMTP Server id 15.2.1118.20 via Frontend Transport; Thu, 1 Dec 2022 07:48:46 -0600 Received: from edi-sw-dsktp-006.ad.cirrus.com (edi-sw-dsktp-006.ad.cirrus.com [198.90.251.111]) by ediswmail.ad.cirrus.com (Postfix) with ESMTP id 0BCC4B38; Thu, 1 Dec 2022 13:48:46 +0000 (UTC) From: Richard Fitzgerald To: , Subject: [PATCH 3/3] soundwire: cadence: Drain the RX FIFO after an IO timeout Date: Thu, 1 Dec 2022 13:48:45 +0000 Message-ID: <20221201134845.4055907-4-rf@opensource.cirrus.com> X-Mailer: git-send-email 2.30.2 In-Reply-To: <20221201134845.4055907-1-rf@opensource.cirrus.com> References: <20221201134845.4055907-1-rf@opensource.cirrus.com> MIME-Version: 1.0 X-Proofpoint-ORIG-GUID: 0xpdTaddmfdlDdsnGRcbsX2iSErxeRUZ X-Proofpoint-GUID: 0xpdTaddmfdlDdsnGRcbsX2iSErxeRUZ X-Proofpoint-Spam-Reason: safe Cc: alsa-devel@alsa-project.org, patches@opensource.cirrus.com, linux-kernel@vger.kernel.org, Richard Fitzgerald , sanyog.r.kale@intel.com, yung-chuan.liao@linux.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" If wait_for_completion_timeout() times-out in _cdns_xfer_msg() it is possible that something could have been written to the RX FIFO. In this case, we should drain the RX FIFO so that anything in it doesn't carry over and mess up the next transfer. Obviously, if we got to this state something went wrong, and we don't really know the state of everything. The cleanup in this situation cannot be bullet-proof but we should attempt to avoid breaking future transaction, if only to reduce the amount of error noise when debugging the failure from a kernel log. Note that this patch only implements the draining for blocking (non-deferred) transfers. The deferred API doesn't have any proper handling of error conditions and would need some re-design before implementing cleanup. That is a task for a separate patch... Signed-off-by: Richard Fitzgerald --- drivers/soundwire/cadence_master.c | 48 ++++++++++++++++-------------- 1 file changed, 26 insertions(+), 22 deletions(-) diff --git a/drivers/soundwire/cadence_master.c b/drivers/soundwire/cadence_master.c index 95c84d9f0775..6bffecf3d61a 100644 --- a/drivers/soundwire/cadence_master.c +++ b/drivers/soundwire/cadence_master.c @@ -555,6 +555,28 @@ cdns_fill_msg_resp(struct sdw_cdns *cdns, return SDW_CMD_OK; } +static void cdns_read_response(struct sdw_cdns *cdns) +{ + u32 num_resp, cmd_base; + int i; + + BUILD_BUG_ON(ARRAY_SIZE(cdns->response_buf) < CDNS_MCP_CMD_LEN); + + num_resp = cdns_readl(cdns, CDNS_MCP_FIFOSTAT); + num_resp &= CDNS_MCP_RX_FIFO_AVAIL; + if (num_resp > ARRAY_SIZE(cdns->response_buf)) { + dev_warn(cdns->dev, "RX AVAIL %d too long\n", num_resp); + num_resp = CDNS_MCP_CMD_LEN; + } + + cmd_base = CDNS_MCP_CMD_BASE; + + for (i = 0; i < num_resp; i++) { + cdns->response_buf[i] = cdns_readl(cdns, cmd_base); + cmd_base += CDNS_MCP_CMD_WORD_LEN; + } +} + static enum sdw_command_response _cdns_xfer_msg(struct sdw_cdns *cdns, struct sdw_msg *msg, int cmd, int offset, int count, bool defer) @@ -596,6 +618,10 @@ _cdns_xfer_msg(struct sdw_cdns *cdns, struct sdw_msg *msg, int cmd, dev_err(cdns->dev, "IO transfer timed out, cmd %d device %d addr %x len %d\n", cmd, msg->dev_num, msg->addr, msg->len); msg->len = 0; + + /* Drain anything in the RX_FIFO */ + cdns_read_response(cdns); + return SDW_CMD_TIMEOUT; } @@ -769,28 +795,6 @@ EXPORT_SYMBOL(cdns_read_ping_status); * IRQ handling */ -static void cdns_read_response(struct sdw_cdns *cdns) -{ - u32 num_resp, cmd_base; - int i; - - BUILD_BUG_ON(ARRAY_SIZE(cdns->response_buf) < CDNS_MCP_CMD_LEN); - - num_resp = cdns_readl(cdns, CDNS_MCP_FIFOSTAT); - num_resp &= CDNS_MCP_RX_FIFO_AVAIL; - if (num_resp > ARRAY_SIZE(cdns->response_buf)) { - dev_warn(cdns->dev, "RX AVAIL %d too long\n", num_resp); - num_resp = CDNS_MCP_CMD_LEN; - } - - cmd_base = CDNS_MCP_CMD_BASE; - - for (i = 0; i < num_resp; i++) { - cdns->response_buf[i] = cdns_readl(cdns, cmd_base); - cmd_base += CDNS_MCP_CMD_WORD_LEN; - } -} - static int cdns_update_slave_status(struct sdw_cdns *cdns, u64 slave_intstat) {