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 BE9A9F433D2 for ; Thu, 16 Apr 2026 00:29:37 +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-Transfer-Encoding: Content-Type:In-Reply-To:From:References:To:Subject:Cc:MIME-Version:Date: Message-ID:Reply-To:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=b7fNNyLnGOcPPmzEQN5mA5MPrcDctArkyQ2ZUb33EbE=; b=mwcxNV8l5CNn/f2dpikRH1iw+h Kadf+RKb+96uj2tWcIia5hDYISW6TPu8+AoiMMltx0P4XpYB93bCO7cwukN+yozAFJvH6OAqHiDEg yMgR93FW3pSuD18DJoOjghJLaCipZznCc4s2mBFeszyGNu3jFhbJx1bc9QSDVy5S/EcpQWsQUwfux spPaMCGfAjdIOFZbNBpdUadkCS6ZXLnV9QOGwrQDntXKsJz/jBFQaxb5x2fvnCvoUn8aCeLODJKWt K0WLSje256AvHelR0nPy4/4lMVNuM0L74aHb47wbM0AzIm8zs2/w8UtJmuTJzTmnU3y07ChFShsZ3 AMzwG1hw==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98.2 #2 (Red Hat Linux)) id 1wDAbt-00000001oih-3qdB; Thu, 16 Apr 2026 00:29:33 +0000 Received: from mail-m9365.xmail.ntesmail.com ([103.126.93.65]) by bombadil.infradead.org with esmtps (Exim 4.98.2 #2 (Red Hat Linux)) id 1wDAbr-00000001oiL-1hGf for linux-arm-kernel@lists.infradead.org; Thu, 16 Apr 2026 00:29:32 +0000 Received: from [172.16.12.17] (unknown [58.22.7.114]) by smtp.qiye.163.com (Hmail) with ESMTP id 3ae6eb0eb; Thu, 16 Apr 2026 08:29:26 +0800 (GMT+08:00) Message-ID: <96fb5db4-0860-b412-11fd-ebcc0b34f887@rock-chips.com> Date: Thu, 16 Apr 2026 08:29:24 +0800 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:91.0) Gecko/20100101 Thunderbird/91.13.1 Cc: shawn.lin@rock-chips.com, linux-mmc@vger.kernel.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-samsung-soc@vger.kernel.org Subject: Re: [PATCH v3 2/2] mmc: dw_mmc: exynos: increase DMA threshold value for exynos7870 To: Kaustabh Chakraborty , Ulf Hansson , Rob Herring , Krzysztof Kozlowski , Conor Dooley , Jaehoon Chung , Krzysztof Kozlowski , Alim Akhtar References: <20260415-dwmmc-dma-thr-v3-0-31014d36b6ee@disroot.org> <20260415-dwmmc-dma-thr-v3-2-31014d36b6ee@disroot.org> From: Shawn Lin In-Reply-To: <20260415-dwmmc-dma-thr-v3-2-31014d36b6ee@disroot.org> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit X-HM-Tid: 0a9d93b1580809cckunm8bc0942b1a9e90 X-HM-MType: 1 X-HM-Spam-Status: e1kfGhgUHx5ZQUpXWQgPGg8OCBgUHx5ZQUlOS1dZFg8aDwILHllBWSg2Ly tZV1koWUFDSUNOT01LS0k3V1ktWUFJV1kPCRoVCBIfWUFZGU1NHlZKSEhLHhlDGB8YGRhWFRQJFh oXVRMBExYaEhckFA4PWVdZGBILWUFZTkNVSUlVTFVKSk9ZV1kWGg8SFR0UWUFZT0tIVUpLSU9PT0 hVSktLVUpCS0tZBg++ DKIM-Signature: a=rsa-sha256; b=FY4wyXPy7pPdpC1z4Oh5qnqUOrHKOYc1xgeKUNcNddoBfDq9QScon2T9WfCqWFexbTg2oG3bTWI+kHBkfLqU45+jpDOxjlPWiTVWadVqLRSlXCyuVcEOeAZzAnwruf5tJDuawE0F794L3wUZJE/pqFtBfiC3mErYtFsi4djKqRc=; c=relaxed/relaxed; s=default; d=rock-chips.com; v=1; bh=b7fNNyLnGOcPPmzEQN5mA5MPrcDctArkyQ2ZUb33EbE=; h=date:mime-version:subject:message-id:from; X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20260415_172931_656957_1F6F477A X-CRM114-Status: GOOD ( 12.53 ) 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 在 2026/04/15 星期三 23:02, Kaustabh Chakraborty 写道: > Exynos 7870 compatible controllers, such as SDIO ones are not able to > perform DMA transfers for small sizes of data (~16 to ~512 bytes), > resulting in cache issues in subsequent transfers. Increase the DMA > transfer threshold to 512 to allow the shorter transfers to take place, > bypassing DMA. > Reviewed-by: Shawn Lin > Signed-off-by: Kaustabh Chakraborty > --- > drivers/mmc/host/dw_mmc-exynos.c | 1 + > 1 file changed, 1 insertion(+) > > diff --git a/drivers/mmc/host/dw_mmc-exynos.c b/drivers/mmc/host/dw_mmc-exynos.c > index 261344d3a8cfe..4b76b997ddc15 100644 > --- a/drivers/mmc/host/dw_mmc-exynos.c > +++ b/drivers/mmc/host/dw_mmc-exynos.c > @@ -141,6 +141,7 @@ static int dw_mci_exynos_priv_init(struct dw_mci *host) > priv->ctrl_type == DW_MCI_TYPE_EXYNOS7870_SMU) { > /* Quirk needed for certain Exynos SoCs */ > host->quirks |= DW_MMC_QUIRK_FIFO64_32; > + host->dma_threshold = 512; > } > > if (priv->ctrl_type == DW_MCI_TYPE_ARTPEC8) { >