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 A618ECD343F for ; Thu, 7 May 2026 14:29:13 +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:In-Reply-To:References:To: From:Subject:Cc:Message-Id:Date:Content-Type:Content-Transfer-Encoding: Mime-Version:Reply-To:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=CEBLsdC5BhK44Ow0f/DvFi3ITfR7Y2d7VKh8V95wdMY=; b=mFb0/MIn1PWUuoYFN7CyJcHpUf x2WLu+MMjkInHVOo9A7Q3F2zwelLpmySN2XEityD5u1F0yrPy7l4rfKptTFxTIO3qiYsShd5AUDPr 2LvRFDU/1RDXtINiQ2nrRsZH4xX1xMH4ouGDlDCuiDpL3Ty45Uld6/WkViQ4pVOJCkRlQBOyw9rw/ tO2/Gx4QIqK5JNfFN5ti4k/Cnv19QejANpk5YFlxj1TF2b8E8bRmFxKTqszur3Sc0PQ1zKYNj4cRw iJz+P8Y1T34yYAnJduMVaeIWmEmYSO7QLhtsU+nm9UJXCD6QNwNbMIGLCCosRMnwCyan8dW+cagPa IVdS9UWA==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.99.1 #2 (Red Hat Linux)) id 1wKziq-000000044EC-3Lrs; Thu, 07 May 2026 14:29:04 +0000 Received: from layka.disroot.org ([178.21.23.139]) by bombadil.infradead.org with esmtps (Exim 4.99.1 #2 (Red Hat Linux)) id 1wKzin-000000044D2-3ViO for linux-arm-kernel@lists.infradead.org; Thu, 07 May 2026 14:29:03 +0000 Received: from mail01.disroot.lan (localhost [127.0.0.1]) by disroot.org (Postfix) with ESMTP id 61B2D2763F; Thu, 7 May 2026 16:28:49 +0200 (CEST) X-Virus-Scanned: SPAM Filter at disroot.org Received: from layka.disroot.org ([127.0.0.1]) by localhost (disroot.org [127.0.0.1]) (amavis, port 10024) with ESMTP id 0bPPlxm6rDu1; Thu, 7 May 2026 16:28:48 +0200 (CEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=disroot.org; s=mail; t=1778164128; bh=CEBLsdC5BhK44Ow0f/DvFi3ITfR7Y2d7VKh8V95wdMY=; h=Date:Cc:Subject:From:To:References:In-Reply-To; b=H9g0LH3RjjyzOIC1+Hk+5regrB3BjwoyxdcW1xunzecRiKfuYk1yWQWLiQ2PQYKly oezPg000Kdfk1X7f3a/XorXtnsJ8OG/IDaP/mwds/DSfjNCwKK3p6kbbesEeariTVr IdOvjfyTyTuHziMn1ex6m2E4ksdyWDzNqALxQO2TBrh+GbbYKDHEDAtfep8u39NZ7+ 0eOJKDiiM3WVcyepFVFi45W1DNtuaY1vfY0D9S4L2ZRbtXeMs5StXkICxJbQW/fodK vRzUOhv0LGI2zzIG7Y/rjhmV1Chq6JKTa83qJiK/KbvUg/oiGO7Gj68ZKRnxNLdf9w QCtclKZc+PvnA== Mime-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset=UTF-8 Date: Thu, 07 May 2026 19:58:32 +0530 Message-Id: Cc: , , , , Subject: Re: [PATCH v3 0/2] Configuring DMA threshold value for DW-MMC controllers From: "Kaustabh Chakraborty" To: "Kaustabh Chakraborty" , "Ulf Hansson" , "Rob Herring" , "Krzysztof Kozlowski" , "Conor Dooley" , "Jaehoon Chung" , "Shawn Lin" , "Krzysztof Kozlowski" , "Alim Akhtar" References: <20260415-dwmmc-dma-thr-v3-0-31014d36b6ee@disroot.org> In-Reply-To: <20260415-dwmmc-dma-thr-v3-0-31014d36b6ee@disroot.org> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.9.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20260507_072902_290916_1805C1DD X-CRM114-Status: GOOD ( 12.29 ) 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 On 2026-04-15 20:32 +05:30, Kaustabh Chakraborty wrote: > In Samsung Exynos 7870 devices with Broadcom Wi-Fi, it has been observed > that small sized DMA transfers are unreliable and are not written > properly, which renders the cache incoherent. > > Experimental observations say that DMA transfer sizes of somewhere > around 64 to 512 are intolerable. We must thus implement a mechanism to > fall back to PIO transfer in this case. One such approach, which this > series implements is allowing the DMA transfer threshold, which is > already defined in the driver, to be configurable. > > Note that this patch is likely to be labelled as a workaround. These > smaller transfers seem to be successful from downstream kernels, > however efforts to figure out how so went in vain. It is also very > possible that the downstream Broadcom Wi-Fi SDIO driver uses PIO > transfers as well. > > Signed-off-by: Kaustabh Chakraborty Hi, bump! What's the status of this patch series? Both patches have been reviewed.