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=-0.6 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=no 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 23578C3A589 for ; Fri, 16 Aug 2019 02:25:58 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id D9162206C1 for ; Fri, 16 Aug 2019 02:25:57 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="LvvLFypJ" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726363AbfHPCZ5 (ORCPT ); Thu, 15 Aug 2019 22:25:57 -0400 Received: from mail-io1-f66.google.com ([209.85.166.66]:36901 "EHLO mail-io1-f66.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726329AbfHPCZ5 (ORCPT ); Thu, 15 Aug 2019 22:25:57 -0400 Received: by mail-io1-f66.google.com with SMTP id q22so3307099iog.4; Thu, 15 Aug 2019 19:25:56 -0700 (PDT) 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=/fibelXvW+1LdGP+tmxyfYovRPGaPOb71lYeqEJPE9w=; b=LvvLFypJqUtGcuZAf7ZZQjdIPS/eQWQeafYVUPKL0TI7ZJ3ta88iENF7vQ0U3UtOEe 02YnSNW4M8rIg/utVyCb8+KAtzniL/7SQyZEBFlXCM+D+B1v7XrbE7hlJ6TE98z40BJD ZBIKgVBaJqaiq+sqCWlRDoXRmy8DkG6FuBGG6RHONt919JykRE3qnSXyUj3KOgJ4BmD2 /+nmFsNnn/93bVI0P1voTaMAxIwmhLKwdryt9Xp+UVBlGoVMWEMHR7yf7nMuJBr4q7PB 5Lyczt7kyUz9eR9fMBILvzTKdPYDd3AtHTXBKo+ijHKr5r6GuVgInnjZTmPvy0TYxAYg F/cw== 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=/fibelXvW+1LdGP+tmxyfYovRPGaPOb71lYeqEJPE9w=; b=otcjsziFZo+yxVUXINuDRuYcvRHz60rBxH6jcC3c9Ts8HvrXj65pLRW9jpQPoLe+4R kFX0FrNccEP5MKddfoTfHmCNGiaR7ylW5orfJ+em78AjcdFCy6bqrHqoNoLJPObjPNdg tAOOilP+PmuFDCPIkwLM1boZi5Vbch8igudzrFLJJRDy/FY0yVoaSFL/MguFkO+9l8IY 3+12872h3OAUwci3ec6abFvXi28Wz3+/smL+OJUf41P2TLPtOpIoBnZspkr2tiOQmKtA JciP045UBUMNqCQ6T6rmRdXIA6hiuQk+jP7Fnh6PnWBXa+p3fRXW27BTrXKL/wm7qL5X 1jaQ== X-Gm-Message-State: APjAAAXkcSjg6X9miI61+UDANCCsZAOo6Dnr7yZXiZwIdWuBUBWGaB+c cPb3EUViHAXulCE2NGAHl7e2ZrMhRSPz0Bsqxu0= X-Google-Smtp-Source: APXvYqyfmapAZhacZLbg2eN8uGz/g14h/u54c3qPjhPxRzsQXwC5ZPILLOCDagZSKqk7giCm7DH7ECRbNI8H/GXpZjk= X-Received: by 2002:a02:8387:: with SMTP id z7mr1847813jag.117.1565922355684; Thu, 15 Aug 2019 19:25:55 -0700 (PDT) MIME-Version: 1.0 References: <20190613005109.1867-1-jassisinghbrar@gmail.com> <20190613005247.2048-1-jassisinghbrar@gmail.com> <20190624064442.GW2962@vkoul-mobl> In-Reply-To: <20190624064442.GW2962@vkoul-mobl> From: Jassi Brar Date: Thu, 15 Aug 2019 21:25:44 -0500 Message-ID: Subject: Re: [PATCH 2/2] dmaengine: milbeaut-hdmac: Add HDMAC driver for Milbeaut platforms To: Vinod Koul Cc: dmaengine@vger.kernel.org, Devicetree List , Linux Kernel Mailing List , Rob Herring , Mark Rutland , orito.takao@socionext.com, Masami Hiramatsu , kasai.kazuhiro@socionext.com, Jassi Brar Content-Type: text/plain; charset="UTF-8" Sender: dmaengine-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: dmaengine@vger.kernel.org On Mon, Jun 24, 2019 at 1:47 AM Vinod Koul wrote: > > On 12-06-19, 19:52, jassisinghbrar@gmail.com wrote: > > > +#include > > +#include > > +#include > > +#include > > +#include > > +#include > > +#include > > +#include > > +#include > > +#include > > Do we need both, IIRC of_dma.h does include of.h! > OK > > +/* mc->vc.lock must be held by caller */ > > +static void milbeaut_chan_start(struct milbeaut_hdmac_chan *mc, > > + struct milbeaut_hdmac_desc *md) > > +{ > > + struct scatterlist *sg; > > + u32 cb, ca, src_addr, dest_addr, len; > ^^ > double space > OK > > +static irqreturn_t milbeaut_hdmac_interrupt(int irq, void *dev_id) > > +{ > > + struct milbeaut_hdmac_chan *mc = dev_id; > > + struct milbeaut_hdmac_desc *md; > > + irqreturn_t ret = IRQ_HANDLED; > > + u32 val; > > + > > + spin_lock(&mc->vc.lock); > > + > > + /* Ack and Disable irqs */ > > + val = readl_relaxed(mc->reg_ch_base + MLB_HDMAC_DMACB); > > + val &= ~(FIELD_PREP(MLB_HDMAC_SS, 0x7)); > ^^^^ > Magic ..? > OK, will define a macro for 7 > > +static int milbeaut_hdmac_chan_pause(struct dma_chan *chan) > > +{ > > + struct virt_dma_chan *vc = to_virt_chan(chan); > > + struct milbeaut_hdmac_chan *mc = to_milbeaut_hdmac_chan(vc); > > + u32 val; > > + > > + spin_lock(&mc->vc.lock); > > + val = readl_relaxed(mc->reg_ch_base + MLB_HDMAC_DMACA); > > + val |= MLB_HDMAC_PB; > > + writel_relaxed(val, mc->reg_ch_base + MLB_HDMAC_DMACA); > > We really should have an updatel() and friends in kernel, feel free to > add in your driver though! > I'll pass on that for now. > > +static int milbeaut_hdmac_chan_init(struct platform_device *pdev, > > + struct milbeaut_hdmac_device *mdev, > > + int chan_id) > > +{ > > + struct device *dev = &pdev->dev; > > + struct milbeaut_hdmac_chan *mc = &mdev->channels[chan_id]; > > + char *irq_name; > > + int irq, ret; > > + > > + irq = platform_get_irq(pdev, chan_id); > > + if (irq < 0) { > > + dev_err(&pdev->dev, "failed to get IRQ number for ch%d\n", > > + chan_id); > > + return irq; > > + } > > + > > + irq_name = devm_kasprintf(dev, GFP_KERNEL, "milbeaut-hdmac-%d", > > + chan_id); > > + if (!irq_name) > > + return -ENOMEM; > > + > > + ret = devm_request_irq(dev, irq, milbeaut_hdmac_interrupt, > > + IRQF_SHARED, irq_name, mc); > > I tend to dislike using devm_request_irq(), we have no control over when > the irq is freed and what is a spirious irq is running while we are > unrolling, so IMHO it make sense to free up and ensure all tasklets are > quiesced when remove returns > If the code is written clean and tight we need not be so paranoid. > > + if (ret) > > + return ret; > > + > > + mc->mdev = mdev; > > + mc->reg_ch_base = mdev->reg_base + MLB_HDMAC_CH_STRIDE * (chan_id + 1); > > + mc->vc.desc_free = milbeaut_hdmac_desc_free; > > + vchan_init(&mc->vc, &mdev->ddev); > > who kills the vc->task? > vchan_synchronize() called from milbeaut_hdmac_synchronize() > > +static int milbeaut_hdmac_remove(struct platform_device *pdev) > > +{ > > + struct milbeaut_hdmac_device *mdev = platform_get_drvdata(pdev); > > + struct dma_chan *chan; > > + int ret; > > + > > + /* > > + * Before reaching here, almost all descriptors have been freed by the > > + * ->device_free_chan_resources() hook. However, each channel might > > + * be still holding one descriptor that was on-flight at that moment. > > + * Terminate it to make sure this hardware is no longer running. Then, > > + * free the channel resources once again to avoid memory leak. > > + */ > > + list_for_each_entry(chan, &mdev->ddev.channels, device_node) { > > + ret = dmaengine_terminate_sync(chan); > > + if (ret) > > + return ret; > > + milbeaut_hdmac_free_chan_resources(chan); > > + } > > + > > + of_dma_controller_free(pdev->dev.of_node); > > + dma_async_device_unregister(&mdev->ddev); > > + clk_disable_unprepare(mdev->clk); > > And as suspected we have active tasklets and irq at this time :( > Not sure how is that.... thanks.