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 X-Spam-Level: X-Spam-Status: No, score=-0.8 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_PASS,URIBL_BLOCKED autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 3997CC43441 for ; Thu, 29 Nov 2018 10:00:27 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id EA54B20868 for ; Thu, 29 Nov 2018 10:00:26 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="SLsAmmd/" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org EA54B20868 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=gmail.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727229AbeK2VFM (ORCPT ); Thu, 29 Nov 2018 16:05:12 -0500 Received: from mail-lf1-f67.google.com ([209.85.167.67]:41822 "EHLO mail-lf1-f67.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726621AbeK2VFM (ORCPT ); Thu, 29 Nov 2018 16:05:12 -0500 Received: by mail-lf1-f67.google.com with SMTP id c16so962822lfj.8; Thu, 29 Nov 2018 02:00:23 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=qA1DNuw+7GiqVUBAahLlA+0uqyff0Brlhy+2UZlD/dI=; b=SLsAmmd/zyPgskuVNZESLCfDNFRyNP7fwMGHhMdA8qe4qBfE1rvCxWmCPAhhHuzhf1 XyyUQN6lGLg2g+BdjeAj5AZvKREtbMYJlemqmz+McRMYlnHqm6ZBJ86yc5e15gDmIaY/ HZmhk9QqCPmp/w2056tXZZI5CztUA66cCRbLeFROjaKpJwDS9rP6b+EUVVItWnVKVua5 QKoqWEVhA0Km0k11fll9bTcrw5zGz5aJVCJfDYMRelp1M/NRHV9kKX+irEY730BbiEg8 lWzU3DOjsMA+8L9TLh3OTHfTsuJod9SjRJai6QZsz2IU4n+WQjf+yFLuFdaFtB2mdkMz g4Bg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=qA1DNuw+7GiqVUBAahLlA+0uqyff0Brlhy+2UZlD/dI=; b=SMLwTrIphawQGZGWBMMv7BOa/IDsrKqoCkIslLtlWgRR+3FLby5gUA5zhKmfakIsRv 6aeBXAsrKkIMBMyxsSs9nI6kMzWS6XXQf2LPHezjriE0RULOZ/kDrxRU79zqa6XZzcfS oLugbS1J7o9blDhICqUmEhMAUk45VuUOQ1fBJbLca4rtqVdUvIlgU8bXe92Wkxs9BASv KEPMCfMW0XYzh2Ux1F29NOZABTnOWjQUbJQmYYh4Bc5no/Q/aWH6x6v4MuQKboQ02Gf3 hvgatveS8r9WxrM9Z8inSM6kcCeNgHydu7XzJyNx7H7ofOcigULP2+E7/9HvLb1AT7bF 4Xrg== X-Gm-Message-State: AA+aEWa9OskPqX7GvBJV6syYvqQlAXw6CFma6DhIlxuiiGCImtwNflky U4tUspr5vEABTQgx6n5gbDv62ow03bQSBhWyW9A= X-Google-Smtp-Source: AFSGD/UiRVhqMm8zhmPaCDXqpaVX6gohIegDv+i1ouoH6K6CUIpbh3Ryt+GJ79XVsRKh27x84mNT86t44QO6E04lvyw= X-Received: by 2002:a19:d58e:: with SMTP id m136mr638831lfg.70.1543485623040; Thu, 29 Nov 2018 02:00:23 -0800 (PST) MIME-Version: 1.0 References: <1542007566-9449-1-git-send-email-zhang.chunyan@linaro.org> <1542007566-9449-2-git-send-email-zhang.chunyan@linaro.org> <84836600-c705-9ac3-297e-bb67a611daca@intel.com> In-Reply-To: From: Chunyan Zhang Date: Thu, 29 Nov 2018 17:59:46 +0800 Message-ID: Subject: Re: [PATCH v2 1/3] mmc: sdhci: add support for using external DMA devices To: Adrian Hunter Cc: Chunyan Zhang , Ulf Hansson , linux-mmc@vger.kernel.org, Linux Kernel Mailing List , Arnd Bergmann , Mark Brown , kishon@ti.com, nsekhar@ti.com Content-Type: text/plain; charset="UTF-8" Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Adrian, On Thu, 29 Nov 2018 at 15:36, Adrian Hunter wrote: > > On 29/11/18 8:22 AM, Chunyan Zhang wrote: > > On Tue, 20 Nov 2018 at 21:41, Adrian Hunter wrote: > >> > >> On 12/11/18 9:26 AM, Chunyan Zhang wrote: > >>> Some standard SD host controllers can support both external dma > >>> controllers as well as ADMA/SDMA in which the SD host controller > >>> acts as DMA master. TI's omap controller is the case as an example. > >>> > >>> Currently the generic SDHCI code supports ADMA/SDMA integrated in > >>> the host controller but does not have any support for external DMA > >>> controllers implemented using dmaengine, meaning that custom code is > >>> needed for any systems that use an external DMA controller with SDHCI. > >> > >> I still think you probably need to reset the DMA if there are transfer > >> errors - perhaps you could comment on that. Also there are some comments below. > > > > With regard to "transfer error", do you mean if > > sdhci_external_dma_setup() failed? > > No, I mean any error interrupt that can leave the DMA uncompleted. For > SDHCI, resetting the data circuit cleans that up, but presumably something > is needed for external DMA? Yes, it should need a dmaengine_terminate_all(). How about adding that at here (I will wrap it up of course): https://elixir.bootlin.com/linux/v4.19.5/source/drivers/mmc/host/sdhci.c#L2553 Is there somewhere else I'm missing? Thanks, Chunyan