From patchwork Fri Dec 2 16:18:12 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Richard Fitzgerald X-Patchwork-Id: 630650 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 5FD44C4321E for ; Fri, 2 Dec 2022 16:20:13 +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 6759F1878; Fri, 2 Dec 2022 17:19:21 +0100 (CET) DKIM-Filter: OpenDKIM Filter v2.11.0 alsa0.perex.cz 6759F1878 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=alsa-project.org; s=default; t=1669998011; bh=55sARawPaV4j4smjlWMxmob8AS1DvrcbNH9nsVsmnrw=; h=From:To:Subject:Date:In-Reply-To:References:Cc:List-Id: List-Unsubscribe:List-Archive:List-Post:List-Help:List-Subscribe: From; b=sMjAfHiapIOfsPAfFDfHds85pktQnN5RNACmkBMbfzJnl62XuvgNVVrEzUKojnI4F CtlwX5Qeqq6WrDn2k5uTQz2DG3zdY/9QPSJXE3xIzWGu3o77fuEqlmwBehieyYHeim N7cNr9wTQnL3JT/pKNOdC+2i66BNv3P6I1n/meec= Received: from alsa1.perex.cz (localhost.localdomain [127.0.0.1]) by alsa1.perex.cz (Postfix) with ESMTP id 2CBA5F8055A; Fri, 2 Dec 2022 17:18:30 +0100 (CET) Received: by alsa1.perex.cz (Postfix, from userid 50401) id 2ECEDF804B3; Fri, 2 Dec 2022 17:18:28 +0100 (CET) Received: from mx0b-001ae601.pphosted.com (mx0b-001ae601.pphosted.com [67.231.152.168]) (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 D1C8AF804B3 for ; Fri, 2 Dec 2022 17:18:16 +0100 (CET) DKIM-Filter: OpenDKIM Filter v2.11.0 alsa1.perex.cz D1C8AF804B3 Authentication-Results: alsa1.perex.cz; dkim=pass (2048-bit key) header.d=cirrus.com header.i=@cirrus.com header.b="HYCxCbLP" Received: from pps.filterd (m0077474.ppops.net [127.0.0.1]) by mx0b-001ae601.pphosted.com (8.17.1.19/8.17.1.19) with ESMTP id 2B28j12l022681; Fri, 2 Dec 2022 10:18:15 -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=BE++jpEueF2GegZwNGVzOdbbuVP+vf8cC+Lif4Aj6fo=; b=HYCxCbLPyppYyzeG8rj1vuGq/Oi8jz0GcR93F3L0tdyquAMShqFb+KcSp5yG8SaFoY0S +d1XJMoj0QYbp22CPSSuvFySXrYIGBz2+4q1UWVJgtbCZHmNxJ15IUvZ0ocTFrJnRmpU lEnA34wnsMRUcE11odnTp+LYMZFFt7FZz8DlvxhGgVdaWe46sgxFxw2bCeJu9tGiY6r8 d+Flpv/KrX2Xy70TkqIkn70zop9bvP5g4twd8iQ0n/Bj03FTKqOsOhrEuklF75b1CRDV vnm7QaUsrjkNmMT8cSY1jQvWYeYc1gv0DlEeqlBJEJpa+AoBrgTSsSBrstgH4pkADJsc bg== Received: from ediex01.ad.cirrus.com ([84.19.233.68]) by mx0b-001ae601.pphosted.com (PPS) with ESMTPS id 3m6k2vt0n6-2 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Fri, 02 Dec 2022 10:18:14 -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; Fri, 2 Dec 2022 10:18:12 -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; Fri, 2 Dec 2022 10:18:12 -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 9C556B2F; Fri, 2 Dec 2022 16:18:12 +0000 (UTC) From: Richard Fitzgerald To: , Subject: [PATCH v2 3/3] soundwire: cadence: Drain the RX FIFO after an IO timeout Date: Fri, 2 Dec 2022 16:18:12 +0000 Message-ID: <20221202161812.4186897-4-rf@opensource.cirrus.com> X-Mailer: git-send-email 2.30.2 In-Reply-To: <20221202161812.4186897-1-rf@opensource.cirrus.com> References: <20221202161812.4186897-1-rf@opensource.cirrus.com> MIME-Version: 1.0 X-Proofpoint-GUID: JbfrKx6hsDlg3qbXh0BsCbr3l__qe-bI X-Proofpoint-ORIG-GUID: JbfrKx6hsDlg3qbXh0BsCbr3l__qe-bI 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 --- Changes since v1: The change is "the same" but the function that is moved up the file has different content because of changes in patch #2 --- drivers/soundwire/cadence_master.c | 50 ++++++++++++++++-------------- 1 file changed, 27 insertions(+), 23 deletions(-) diff --git a/drivers/soundwire/cadence_master.c b/drivers/soundwire/cadence_master.c index a6635f7f350e..521387322145 100644 --- a/drivers/soundwire/cadence_master.c +++ b/drivers/soundwire/cadence_master.c @@ -555,6 +555,29 @@ 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; + + /* RX_FIFO_AVAIL can be 2 entries more than the FIFO size */ + BUILD_BUG_ON(ARRAY_SIZE(cdns->response_buf) < CDNS_MCP_CMD_LEN + 2); + + 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 = ARRAY_SIZE(cdns->response_buf); + } + + 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 +619,10 @@ _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; } @@ -769,29 +796,6 @@ EXPORT_SYMBOL(cdns_read_ping_status); * IRQ handling */ -static void cdns_read_response(struct sdw_cdns *cdns) -{ - u32 num_resp, cmd_base; - int i; - - /* RX_FIFO_AVAIL can be 2 entries more than the FIFO size */ - BUILD_BUG_ON(ARRAY_SIZE(cdns->response_buf) < CDNS_MCP_CMD_LEN + 2); - - 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 = ARRAY_SIZE(cdns->response_buf); - } - - 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) {