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=-5.2 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, USER_AGENT_SANE_1 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 68FF4C433ED for ; Wed, 19 May 2021 06:06:41 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 4D10D61040 for ; Wed, 19 May 2021 06:06:41 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S243655AbhESGH5 (ORCPT ); Wed, 19 May 2021 02:07:57 -0400 Received: from verein.lst.de ([213.95.11.211]:36800 "EHLO verein.lst.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S240751AbhESGHj (ORCPT ); Wed, 19 May 2021 02:07:39 -0400 Received: by verein.lst.de (Postfix, from userid 2407) id CC0B767373; Wed, 19 May 2021 08:06:17 +0200 (CEST) Date: Wed, 19 May 2021 08:06:17 +0200 From: Christoph Hellwig To: Guo Ren Cc: Christoph Hellwig , Anup Patel , Palmer Dabbelt , drew@beagleboard.org, wefu@redhat.com, lazyparser@gmail.com, linux-riscv , Linux Kernel Mailing List , linux-arch , linux-sunxi@lists.linux.dev, Guo Ren Subject: Re: [PATCH RFC 0/3] riscv: Add DMA_COHERENT support Message-ID: <20210519060617.GA28397@lst.de> References: <1621400656-25678-1-git-send-email-guoren@kernel.org> <20210519052048.GA24853@lst.de> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.17 (2007-11-01) Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, May 19, 2021 at 02:05:00PM +0800, Guo Ren wrote: > Since the existing RISC-V ISA cannot solve this problem, it is better > to provide some configuration for the SOC vendor to customize. We've been talking about this problem for close to five years. So no, if you don't manage to get the feature into the ISA it can't be supported. 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=-5.6 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_1 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 00FBAC433B4 for ; Wed, 19 May 2021 06:06:47 +0000 (UTC) Received: from desiato.infradead.org (desiato.infradead.org [90.155.92.199]) (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 7552561040 for ; Wed, 19 May 2021 06:06:46 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 7552561040 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=lst.de Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-riscv-bounces+linux-riscv=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=desiato.20200630; h=Sender:Content-Transfer-Encoding :Content-Type:List-Subscribe:List-Help:List-Post:List-Archive: List-Unsubscribe:List-Id:In-Reply-To:MIME-Version:References:Message-ID: Subject:Cc:To:From:Date:Reply-To:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=qpbV5T/b27rd8wAZbzskUebdg3FtLyv8YOt3IlXgl+8=; b=ISQvnVUE5dZosSX8yjKuheG9Q FQeK+xq6mH/+SjSZ4x6G9xrFSZpan/GwNdRyEfs18yf7UNiUbhOvA/kp/T1LQlThDrR/CLbEZv2wY oxp5RvtbNpebm8Ss3PwooQR4Unt2JBFArw4TO4Vpgjd/mPMpU+2hG8sO1lBCTkYZPfKdumhexlbkt +XUrwfQzelmNLmtSyUcZ/b7OO+EEvBAs/vFlyIX30dEsuCKbe51BWMH19QZqUFnrUFQhb91wegsVH ZJBg3N7bhxJxmNt/a5ErgDaxOxyvKYVfJTgg+9Gjw8SWQOpa8Zx9M7Z69OrhPciPOx3Bpf2rt1tba Gc0ZV6pKQ==; Received: from localhost ([::1] helo=desiato.infradead.org) by desiato.infradead.org with esmtp (Exim 4.94 #2 (Red Hat Linux)) id 1ljFLf-002wmn-Pb; Wed, 19 May 2021 06:06:27 +0000 Received: from bombadil.infradead.org ([2607:7c80:54:e::133]) by desiato.infradead.org with esmtps (Exim 4.94 #2 (Red Hat Linux)) id 1ljFLb-002wmR-Eu for linux-riscv@desiato.infradead.org; Wed, 19 May 2021 06:06:23 +0000 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=bombadil.20210309; h=In-Reply-To:Content-Type:MIME-Version :References:Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description; bh=O1Txh+t9H+TCovqB3YvN4kfb1Czbwt6zPlHx6LmU8Cs=; b=uHBH6BgEiv1wU73kOIRQ9fxwIR 55YCwHAODKVu1phIFSZNV0GGQyIuT9iwoaRttQyO0riB2dY5a9oyV9Qe+f1mHZWYHvUaWM5fDC+lP edNaUlQCrW+iEACVJtnXPjUeK8bcBRE7/gbJS5OUzcTkQokxlI5l81Mgsn5zA0PTTxRhNuFPIYktX dMSO0WJ1k9urbPpEoc9DbzfL5kCtnb1fKY9hGYcNy0DRp5SzDDnfxDWO9mETmLki8Cef7I0uNaJTd mSedelJM2DDrRxLcFG8dNTt1aCQdQrv2S3xqrdbNDKUEMGZyMptrWB46avolScFg6kAjyxqRB2JOo 8LaVytFw==; Received: from verein.lst.de ([213.95.11.211]) by bombadil.infradead.org with esmtps (Exim 4.94 #2 (Red Hat Linux)) id 1ljFLZ-00FAbP-0s for linux-riscv@lists.infradead.org; Wed, 19 May 2021 06:06:22 +0000 Received: by verein.lst.de (Postfix, from userid 2407) id CC0B767373; Wed, 19 May 2021 08:06:17 +0200 (CEST) Date: Wed, 19 May 2021 08:06:17 +0200 From: Christoph Hellwig To: Guo Ren Cc: Christoph Hellwig , Anup Patel , Palmer Dabbelt , drew@beagleboard.org, wefu@redhat.com, lazyparser@gmail.com, linux-riscv , Linux Kernel Mailing List , linux-arch , linux-sunxi@lists.linux.dev, Guo Ren Subject: Re: [PATCH RFC 0/3] riscv: Add DMA_COHERENT support Message-ID: <20210519060617.GA28397@lst.de> References: <1621400656-25678-1-git-send-email-guoren@kernel.org> <20210519052048.GA24853@lst.de> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.17 (2007-11-01) X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20210518_230621_232991_0AD5B4B4 X-CRM114-Status: GOOD ( 12.39 ) X-BeenThere: linux-riscv@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-riscv" Errors-To: linux-riscv-bounces+linux-riscv=archiver.kernel.org@lists.infradead.org On Wed, May 19, 2021 at 02:05:00PM +0800, Guo Ren wrote: > Since the existing RISC-V ISA cannot solve this problem, it is better > to provide some configuration for the SOC vendor to customize. We've been talking about this problem for close to five years. So no, if you don't manage to get the feature into the ISA it can't be supported. _______________________________________________ linux-riscv mailing list linux-riscv@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-riscv