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=-7.3 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,MENTIONS_GIT_HOSTING,SPF_HELO_NONE,SPF_PASS, USER_AGENT_SANE_1 autolearn=unavailable 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 796C1C4CECE for ; Mon, 14 Oct 2019 21:01:25 +0000 (UTC) Received: from lists.ozlabs.org (lists.ozlabs.org [203.11.71.2]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 2B69B2133F for ; Mon, 14 Oct 2019 21:01:25 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 2B69B2133F Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=arm.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Received: from bilbo.ozlabs.org (lists.ozlabs.org [IPv6:2401:3900:2:1::3]) by lists.ozlabs.org (Postfix) with ESMTP id 46sWFG6JCkzDqxL for ; Tue, 15 Oct 2019 08:01:22 +1100 (AEDT) Authentication-Results: lists.ozlabs.org; spf=pass (mailfrom) smtp.mailfrom=arm.com (client-ip=217.140.110.172; helo=foss.arm.com; envelope-from=catalin.marinas@arm.com; receiver=) Authentication-Results: lists.ozlabs.org; dmarc=none (p=none dis=none) header.from=arm.com Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by lists.ozlabs.org (Postfix) with ESMTP id 46sWBx6b9JzDqQT for ; Tue, 15 Oct 2019 07:59:13 +1100 (AEDT) Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 8A383337; Mon, 14 Oct 2019 13:59:08 -0700 (PDT) Received: from iMac-3.local (unknown [172.31.20.19]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id BA5423F68E; Mon, 14 Oct 2019 13:59:06 -0700 (PDT) Date: Mon, 14 Oct 2019 21:59:00 +0100 From: Catalin Marinas To: Nicolas Saenz Julienne Subject: Re: [PATCH RFC 0/5] ARM: Raspberry Pi 4 DMA support Message-ID: <20191014205859.GA7634@iMac-3.local> References: <20191014183108.24804-1-nsaenzjulienne@suse.de> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20191014183108.24804-1-nsaenzjulienne@suse.de> User-Agent: Mutt/1.11.1 (2018-12-01) X-BeenThere: linuxppc-dev@lists.ozlabs.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: linux-s390@vger.kernel.org, f.fainelli@gmail.com, linuxppc-dev@lists.ozlabs.org, linux-kernel@vger.kernel.org, hch@infradead.org, iommu@lists.linux-foundation.org, mbrugger@suse.com, bcm-kernel-feedback-list@broadcom.com, linux-rpi-kernel@lists.infradead.org, Robin Murphy , linux-arm-kernel@lists.infradead.org, wahrenst@gmx.net Errors-To: linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Sender: "Linuxppc-dev" On Mon, Oct 14, 2019 at 08:31:02PM +0200, Nicolas Saenz Julienne wrote: > the Raspberry Pi 4 offers up to 4GB of memory, of which only the first > is DMA capable device wide. This forces us to use of bounce buffers, > which are currently not very well supported by ARM's custom DMA ops. > Among other things the current mechanism (see dmabounce.c) isn't > suitable for high memory. Instead of fixing it, this series introduces a > way of selecting dma-direct as the default DMA ops provider which allows > for the Raspberry Pi to make use of swiotlb. I presume these patches go on top of this series: http://lkml.kernel.org/r/20190911182546.17094-1-nsaenzjulienne@suse.de which I queued here: https://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git/log/?h=for-next/zone-dma -- Catalin