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 bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (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 78936CDE00E for ; Fri, 26 Jun 2026 09:27:35 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:Content-Type: Content-Transfer-Encoding:MIME-Version:References:In-Reply-To:Message-ID:Date :Subject:CC:To:From:Reply-To:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=EuWXUg+L5G4q1vuW0NzZ7ISjcHJRItNY/483fn+wDKs=; b=Pc0RK5XhlZXh6iotl4QGI0tBk7 0Q9NKgmklse5B6Pp4t54RdOLHKEltnxdXqrCZinLA2ClTKzx3ASbx/9GvAe16j4yQo+AkbCW+0X2o Vcz+ZNlXBBH95rjOFbpOKapJ8N86vy1xfHqe2KUPfl4T4mFzimVGp8V2YGNybDQnNiFkhNR4riAUt Im+uTtSG4VEl8Un4OvzI+fOc5OaeSPt50tGAwZreZk4aIwq5f2EK7bsUbNFp5kaGAvICUw34WYnJe WUQooqhzf9Jb6StTr2Uq5cYW+wg8i7JcxdoR9LQPmXYVyrwBsuwg0L+8oSTAC2pHfsYB/5A97ETRo SNEDDqCg==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.99.1 #2 (Red Hat Linux)) id 1wd2qP-0000000AyuJ-0Jsd; Fri, 26 Jun 2026 09:27:29 +0000 Received: from mail-eastus2azlp170110003.outbound.protection.outlook.com ([2a01:111:f403:c110::3] helo=BN8PR05CU002.outbound.protection.outlook.com) by bombadil.infradead.org with esmtps (Exim 4.99.1 #2 (Red Hat Linux)) id 1wd2qC-0000000Aync-1zSQ for linux-arm-kernel@lists.infradead.org; Fri, 26 Jun 2026 09:27:17 +0000 ARC-Seal: i=1; a=rsa-sha256; s=arcselector10001; d=microsoft.com; cv=none; b=i4ygFtWcTMq9I7N5cOhQ5a+J/Gjy8etnaYnN+rNVobygT4yAw0ZJLzC5dxZ3LXhcCf4R2In6zhWsX3JnwIpCFwiMtoOyefo5gDZY1gw+TW/qgzWK3tbThpcIqcJsUUsqHozcCAOdKnTCyS791dTDZ7dB6T/wZVbAC+XY83gvyxEiq8xFtCbMamRe2d4jAFo0QP8CakrlvOH1rlTMQJmKwL+wfWrkap0/97QWygPDxdNQqm3+sr6QWfplztxHbk1/s2Q8oj2CyO+Qu+TAXlyqYws1HT4Ztg/zNFDsf2Bjs6A4X6n1nqvRvJn4MHFosULpuB0Nzv0lQnzHHONvzg5QfQ== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=microsoft.com; s=arcselector10001; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-AntiSpam-MessageData-ChunkCount:X-MS-Exchange-AntiSpam-MessageData-0:X-MS-Exchange-AntiSpam-MessageData-1; bh=EuWXUg+L5G4q1vuW0NzZ7ISjcHJRItNY/483fn+wDKs=; b=lGWN0RW3Yc8K1DCe+CjTO5Ce33qGP7uG8BGJzUwlzbV1SuCttUBhx+7umkEPwVjNXJH7m+u5VX/rR47nYgNnBlO3lQeqNGCZ3u/8wOeiFS82CX2yLoMZTXNFLNTq7BtMG1w8Ik0HDVynZEfLJxnLM3flG3Qe9PQlUdVFSPXIg9mL/d6b5r5HbxTRYWTEj9CRGTbk5RiySlArp9bN2/n8TCTfp3Jctuha6eXImep8iQpAGqzXbVoaEK6wbyJmKz1WZ8tkrIQwZm2RbzVehUikCSEwbhUXj9clGCCkp/pZQZDdpq4g09mmXm4gOu10tppP5sl3Op0r52xTeYoEdBPFXA== ARC-Authentication-Results: i=1; mx.microsoft.com 1; spf=pass (sender ip is 165.204.84.17) smtp.rcpttodomain=kernel.org smtp.mailfrom=amd.com; dmarc=pass (p=quarantine sp=quarantine pct=100) action=none header.from=amd.com; dkim=none (message not signed); arc=none (0) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=amd.com; s=selector1; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-SenderADCheck; bh=EuWXUg+L5G4q1vuW0NzZ7ISjcHJRItNY/483fn+wDKs=; b=tUprCJGRaf1NPp5CmtBR79YG0Pij95sdD2vq+3YRTyHEHkhUeffWe/mslLSJm8RGfMBAcdSubR0Vb1hXbGMuos3TWa7Rsb6CXISIciX7GfIxu/JGzK++O/X05RRQJAGXHtcbZyJBe4EX9V2ALFsCTrrVcJZqv8uAyD191Xumsfc= Received: from CYZPR05CA0002.namprd05.prod.outlook.com (2603:10b6:930:89::20) by LV8PR12MB9208.namprd12.prod.outlook.com (2603:10b6:408:182::12) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.21.159.17; Fri, 26 Jun 2026 09:27:10 +0000 Received: from CY4PEPF0000EE33.namprd05.prod.outlook.com (2603:10b6:930:89:cafe::7d) by CYZPR05CA0002.outlook.office365.com (2603:10b6:930:89::20) with Microsoft SMTP Server (version=TLS1_3, cipher=TLS_AES_256_GCM_SHA384) id 15.21.181.8 via Frontend Transport; Fri, 26 Jun 2026 09:27:10 +0000 X-MS-Exchange-Authentication-Results: spf=pass (sender IP is 165.204.84.17) smtp.mailfrom=amd.com; dkim=none (message not signed) header.d=none;dmarc=pass action=none header.from=amd.com; Received-SPF: Pass (protection.outlook.com: domain of amd.com designates 165.204.84.17 as permitted sender) receiver=protection.outlook.com; client-ip=165.204.84.17; helo=satlexmb07.amd.com; pr=C Received: from satlexmb07.amd.com (165.204.84.17) by CY4PEPF0000EE33.mail.protection.outlook.com (10.167.242.39) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.21.181.6 via Frontend Transport; Fri, 26 Jun 2026 09:27:09 +0000 Received: from satlexmb10.amd.com (10.181.42.219) by satlexmb07.amd.com (10.181.42.216) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.2562.41; Fri, 26 Jun 2026 04:27:06 -0500 Received: from satlexmb07.amd.com (10.181.42.216) by satlexmb10.amd.com (10.181.42.219) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.2562.41; Fri, 26 Jun 2026 04:27:05 -0500 Received: from xhdsuragupt40.xilinx.com (10.180.168.240) by satlexmb07.amd.com (10.181.42.216) with Microsoft SMTP Server id 15.2.2562.41 via Frontend Transport; Fri, 26 Jun 2026 04:27:04 -0500 From: Suraj Gupta To: , , , CC: , , Subject: [PATCH v3 3/3] dmaengine: xilinx_dma: Optimize control register write and channel start logic for AXIDMA and MCDMA in corresponding start_transfer() Date: Fri, 26 Jun 2026 14:56:56 +0530 Message-ID: <20260626092656.1563871-4-suraj.gupta2@amd.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20260626092656.1563871-1-suraj.gupta2@amd.com> References: <20260626092656.1563871-1-suraj.gupta2@amd.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Content-Type: text/plain X-EOPAttributedMessage: 0 X-MS-PublicTrafficType: Email X-MS-TrafficTypeDiagnostic: CY4PEPF0000EE33:EE_|LV8PR12MB9208:EE_ X-MS-Office365-Filtering-Correlation-Id: 1f8387dd-433a-4c0e-7d63-08ded3651927 X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0;ARA:13230040|376014|23010399003|1800799024|36860700016|82310400026|22082099003|18002099003|56012099006|6133799003|11063799006; X-Microsoft-Antispam-Message-Info: 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 X-Forefront-Antispam-Report: CIP:165.204.84.17;CTRY:US;LANG:en;SCL:1;SRV:;IPV:NLI;SFV:NSPM;H:satlexmb07.amd.com;PTR:InfoDomainNonexistent;CAT:NONE;SFS:(13230040)(376014)(23010399003)(1800799024)(36860700016)(82310400026)(22082099003)(18002099003)(56012099006)(6133799003)(11063799006);DIR:OUT;SFP:1101; X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: HhwofPRdDdYwJCUwXM/JxnzuLKdVgptI1XHVf2vIURmodGbLU6oCwkCxzPI2fss+LMmTMLXSDnK4N8kY29rcfFB5VOwnqwOvFBzSxnDWk1zxb/s5K1nJL94S0wexf9S9JZj4/uupg1tnW6AoUXZX1Ko9xpCZa8v5lQ3tnQwKOaFRDVUPXqtGIUynq2FMhUdBA73LG9C6urMMWgCTUX2t58U7B7ledlUm4FISivNCosZPoYDaUxvTnUFjpUPqx/0Lh3+pi4i+pmD5UZIDJRUyWaRqP8LhuJoSH9yZaleNOvpQ5XO793dt+xBazlUnmQRpFX4KiUmLK5rS2TOd/lHz+ro74IwpJWg7qfJN8ry9/QwdOjVORW9eZoq90JQnEXk7rcLnZhJX9+7Ez9FVFzebpUezU1pJQ/Zxf1uEcz8CWt6J+aIyW+6tDInmF9+sfA2R X-OriginatorOrg: amd.com X-MS-Exchange-CrossTenant-OriginalArrivalTime: 26 Jun 2026 09:27:09.9484 (UTC) X-MS-Exchange-CrossTenant-Network-Message-Id: 1f8387dd-433a-4c0e-7d63-08ded3651927 X-MS-Exchange-CrossTenant-Id: 3dd8961f-e488-4e60-8e11-a82d994e183d X-MS-Exchange-CrossTenant-OriginalAttributedTenantConnectingIp: TenantId=3dd8961f-e488-4e60-8e11-a82d994e183d;Ip=[165.204.84.17];Helo=[satlexmb07.amd.com] X-MS-Exchange-CrossTenant-AuthSource: CY4PEPF0000EE33.namprd05.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Anonymous X-MS-Exchange-CrossTenant-FromEntityHeader: HybridOnPrem X-MS-Exchange-Transport-CrossTenantHeadersStamped: LV8PR12MB9208 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.9.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20260626_022716_520052_AE613FE1 X-CRM114-Status: GOOD ( 10.49 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org Optimize AXI DMA control register programming by consolidating coalesce count and delay configuration into a single register write. Previously, the coalesce count was written separately from the delay configuration, resulting in two register writes. Combine these into one write operation to reduce bus overhead. Additionally, avoid redundant channel starts in xilinx_dma_start_transfer() and xilinx_mcdma_start_transfer() by only calling xilinx_dma_start() when the channel is actually idle. Tested-by: Folker Schwesinger Signed-off-by: Suraj Gupta Co-developed-by: Srinivas Neeli Signed-off-by: Srinivas Neeli --- drivers/dma/xilinx/xilinx_dma.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-) diff --git a/drivers/dma/xilinx/xilinx_dma.c b/drivers/dma/xilinx/xilinx_dma.c index 6e7b183cb499..829601d8a16f 100644 --- a/drivers/dma/xilinx/xilinx_dma.c +++ b/drivers/dma/xilinx/xilinx_dma.c @@ -1603,7 +1603,6 @@ static void xilinx_dma_start_transfer(struct xilinx_dma_chan *chan) reg &= ~XILINX_DMA_CR_COALESCE_MAX; reg |= chan->desc_pendingcount << XILINX_DMA_CR_COALESCE_SHIFT; - dma_ctrl_write(chan, XILINX_DMA_REG_DMACR, reg); } if (chan->has_sg && list_empty(&chan->active_list)) @@ -1614,7 +1613,8 @@ static void xilinx_dma_start_transfer(struct xilinx_dma_chan *chan) reg |= XILINX_DMA_DMAXR_ALL_IRQ_MASK; dma_ctrl_write(chan, XILINX_DMA_REG_DMACR, reg); - xilinx_dma_start(chan); + if (chan->idle) + xilinx_dma_start(chan); if (chan->err) return; @@ -1703,7 +1703,8 @@ static void xilinx_mcdma_start_transfer(struct xilinx_dma_chan *chan) reg |= XILINX_MCDMA_CR_RUNSTOP_MASK; dma_ctrl_write(chan, XILINX_MCDMA_CHAN_CR_OFFSET(chan->tdest), reg); - xilinx_dma_start(chan); + if (chan->idle) + xilinx_dma_start(chan); if (chan->err) return; -- 2.25.1