From patchwork Fri Dec 2 16:18:11 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Richard Fitzgerald X-Patchwork-Id: 630651 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 4AD51C4321E for ; Fri, 2 Dec 2022 16:19:39 +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 4BA1E1853; Fri, 2 Dec 2022 17:18:47 +0100 (CET) DKIM-Filter: OpenDKIM Filter v2.11.0 alsa0.perex.cz 4BA1E1853 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=alsa-project.org; s=default; t=1669997977; bh=S676DTjodRk/OZG7p/RLRW1OnJDKfDxq9TE3YOX1BmI=; h=From:To:Subject:Date:In-Reply-To:References:Cc:List-Id: List-Unsubscribe:List-Archive:List-Post:List-Help:List-Subscribe: From; b=DCLzJedEvGUhKSDPfP2ALUdjsaNJG8Be37/FmrW/MlIY5ildGaG7edCEIitlQohjF MATHfD92MKFLiJjgwdvQX7Uet8Vm18zLrXEA2vTULPpBE1rBvadb+9x9gERtnY6hYf X/3C53+4oDCMM3+70Xye1LZLYidApRAQCOC618j4= Received: from alsa1.perex.cz (localhost.localdomain [127.0.0.1]) by alsa1.perex.cz (Postfix) with ESMTP id E4045F80557; Fri, 2 Dec 2022 17:18:25 +0100 (CET) Received: by alsa1.perex.cz (Postfix, from userid 50401) id 1BBD2F804D6; Fri, 2 Dec 2022 17:18:23 +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 BA2AAF80310 for ; Fri, 2 Dec 2022 17:18:16 +0100 (CET) DKIM-Filter: OpenDKIM Filter v2.11.0 alsa1.perex.cz BA2AAF80310 Authentication-Results: alsa1.perex.cz; dkim=pass (2048-bit key) header.d=cirrus.com header.i=@cirrus.com header.b="jHfhA1Oj" 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 2B25sRqo018164; 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=fnOUlVD1+EfyAjC/Rot3TtuSZIDDO+MesIulzw8RRDQ=; b=jHfhA1OjEIaECty7TP/89pujFIqgTTgH6+c9iZd6lJrGr3xBOGURNWkatOd8iy6cDlwC eQ2IDl0RyPiV6e6C8pu7xbziLneKTFXlGJiq7wTkLK25yeGSbFdJd3XBfrEYip7/NqUV CDj8L9nTNfWkwzzRJpuMNeyBaMpwEOzLVOU9zQ+AT0mwVr2NRwr+zgS797/kItnG1eJg cy3iW1rgCinZYzmCSfEWaajSl0aryp76SHZw8ttpPBdgFP94C+ikMWld7GW7MTnIdM3M f0C1+Ffprab4pZIMb+9pdMHAaSmw5p2U48vLvyxHnO9FPbb3YuL0wBkHFM6JFNPegsok gA== Received: from ediex02.ad.cirrus.com ([84.19.233.68]) by mx0b-001ae601.pphosted.com (PPS) with ESMTPS id 3m6k2vt0n5-2 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Fri, 02 Dec 2022 10:18:14 -0600 Received: from ediex02.ad.cirrus.com (198.61.84.81) by ediex02.ad.cirrus.com (198.61.84.81) 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 anon-ediex02.ad.cirrus.com (198.61.84.81) 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 8B719B38; Fri, 2 Dec 2022 16:18:12 +0000 (UTC) From: Richard Fitzgerald To: , Subject: [PATCH v2 2/3] soundwire: cadence: Remove wasted space in response_buf Date: Fri, 2 Dec 2022 16:18:11 +0000 Message-ID: <20221202161812.4186897-3-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: xtqEQNcKQUURuLF1eA2wera7p7oe0Y3I X-Proofpoint-ORIG-GUID: xtqEQNcKQUURuLF1eA2wera7p7oe0Y3I 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" The response_buf was declared much larger (128 entries) than the number of responses that could ever be written into it. The Cadence IP is configurable up to a maximum of 32 entries, and the datasheet says that RX_FIFO_AVAIL can be 2 larger than this. So allow up to 34 responses. Also add checking in cdns_read_response() to prevent overflowing reponse_buf if RX_FIFO_AVAIL contains an unexpectedly large number. Signed-off-by: Richard Fitzgerald --- Changes since v1: - Make response_buf large enough for the maximum IP config of 32 plus the mysterious extra 2. - If RX_FIFO_AVAIL is too big trim it to the size of response_buf instead of CDNS_MCP_CMD_LEN. --- drivers/soundwire/cadence_master.c | 7 +++++++ drivers/soundwire/cadence_master.h | 13 ++++++++++++- 2 files changed, 19 insertions(+), 1 deletion(-) diff --git a/drivers/soundwire/cadence_master.c b/drivers/soundwire/cadence_master.c index 27699f341f2c..a6635f7f350e 100644 --- a/drivers/soundwire/cadence_master.c +++ b/drivers/soundwire/cadence_master.c @@ -774,8 +774,15 @@ 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; diff --git a/drivers/soundwire/cadence_master.h b/drivers/soundwire/cadence_master.h index 0434d70d4b1f..e0a64b28c6b9 100644 --- a/drivers/soundwire/cadence_master.h +++ b/drivers/soundwire/cadence_master.h @@ -8,6 +8,12 @@ #define SDW_CADENCE_GSYNC_KHZ 4 /* 4 kHz */ #define SDW_CADENCE_GSYNC_HZ (SDW_CADENCE_GSYNC_KHZ * 1000) +/* + * The Cadence IP supports up to 32 entries in the FIFO, though implementations + * can configure the IP to have a smaller FIFO. + */ +#define CDNS_MCP_IP_MAX_CMD_LEN 32 + /** * struct sdw_cdns_pdi: PDI (Physical Data Interface) instance * @@ -117,7 +123,12 @@ struct sdw_cdns { struct sdw_bus bus; unsigned int instance; - u32 response_buf[0x80]; + /* + * The datasheet says the RX FIFO AVAIL can be 2 entries more + * than the FIFO capacity, so allow for this. + */ + u32 response_buf[CDNS_MCP_IP_MAX_CMD_LEN + 2]; + struct completion tx_complete; struct sdw_defer *defer;