From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-m19731107.qiye.163.com (mail-m19731107.qiye.163.com [220.197.31.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 940B022F01; Thu, 16 Apr 2026 00:34:44 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=220.197.31.107 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1776299689; cv=none; b=So4tD/c1Vv/VOE5fEgUbHDsFP7FBeJ/L15U0rOZbnsGuoKpN4GmjS1LoT/nwmW8eDpAxgi3TkjBfU3UQOEPggbfUa/dsy5Si6s8DvdTDqlTku43VYiS6WbfulwZx0K+1F+zUrOQTWpkkem+yoaUdWJpunY2emQfyALym19ao604= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1776299689; c=relaxed/simple; bh=1jAoubjJnmVgq0+B2OIwZJa2GJ6034gsrMgbkfWyrjs=; h=Message-ID:Date:MIME-Version:Cc:Subject:To:References:From: In-Reply-To:Content-Type; b=H7x/QJpE5rFbQFiqHs+rUDHk9CYMTRcnPZXlCNCW6Eii7X/bZbsgbLsAL77fZDTP6d+4g0sJLn+5iQzf0HVJVZlrEvwVuhB0qE3Vd9auh6yjlJ4wlLCGpzLvycIr6QysEh8H72Sr41grnMe/2bcUNsBmyaxdsKFKwgK95FkTpzI= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=rock-chips.com; spf=pass smtp.mailfrom=rock-chips.com; dkim=pass (1024-bit key) header.d=rock-chips.com header.i=@rock-chips.com header.b=FY4wyXPy; arc=none smtp.client-ip=220.197.31.107 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=rock-chips.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=rock-chips.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=rock-chips.com header.i=@rock-chips.com header.b="FY4wyXPy" 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 Precedence: bulk X-Mailing-List: devicetree@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: 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; 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) { >