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=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI,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 4D80DC433E1 for ; Fri, 3 Jul 2020 13:37:41 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 22A4620782 for ; Fri, 3 Jul 2020 13:37:41 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1593783461; bh=h4AWXK1OzAabGjzRp78Qq4E/Pvb4iF6SmMTMkbta69E=; h=Date:From:To:Cc:Subject:References:In-Reply-To:List-ID:From; b=SrkuL6YsTTtiYthQ4FzS0W4ZHbpP3inwgwu/GJFFUBGMqPUwz70KrwP8laFe7kxUK KpxqXVREeqQCRgpuoWMKPZ1MLFBAVk1qpAuUGQLOoZI/1MYaZuG0lhBc30Y3eKILgH 5F1oVF3ZLu6dyBkiddY5z6+bnG8CNIx28vzUJgIY= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726265AbgGCNhk (ORCPT ); Fri, 3 Jul 2020 09:37:40 -0400 Received: from mail.kernel.org ([198.145.29.99]:34110 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726022AbgGCNhj (ORCPT ); Fri, 3 Jul 2020 09:37:39 -0400 Received: from willie-the-truck (236.31.169.217.in-addr.arpa [217.169.31.236]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 3EF09206A1; Fri, 3 Jul 2020 13:37:36 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1593783459; bh=h4AWXK1OzAabGjzRp78Qq4E/Pvb4iF6SmMTMkbta69E=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=Zsco0pFHiu8uFn++3g+2aWZOGtMeDwXe2RdiKWXSiB1NAwLZTkzuswi6E4rPfoFgc zQygwRBRrnKJMJ6YgutuQW39JaKYOgP2fttYqHsRZiFYssPejgjJ+6IYnBSkwhnVMp cs70jkYqgCEvqEZxEg9urRaC6/8frYrllSxaMCbY= Date: Fri, 3 Jul 2020 14:37:33 +0100 From: Will Deacon To: Sai Prakash Ranjan Cc: Robin Murphy , Joerg Roedel , Jordan Crouse , Rob Clark , iommu@lists.linux-foundation.org, linux-arm-msm@vger.kernel.org, linux-kernel@vger.kernel.org, Sean Paul , Sharat Masetty , Akhil P Oommen , freedreno@lists.freedesktop.org, Daniel Vetter , David Airlie , Emil Velikov , dri-devel@lists.freedesktop.org, linux-arm-kernel@lists.infradead.org, "Kristian H . Kristensen" , Stephen Boyd , Matthias Kaehlcke Subject: Re: [PATCHv3 7/7] drm/msm/a6xx: Add support for using system cache(LLC) Message-ID: <20200703133732.GD18953@willie-the-truck> References: <449a6544b10f0035d191ac52283198343187c153.1593344120.git.saiprakash.ranjan@codeaurora.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <449a6544b10f0035d191ac52283198343187c153.1593344120.git.saiprakash.ranjan@codeaurora.org> User-Agent: Mutt/1.10.1 (2018-07-13) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Jun 29, 2020 at 09:22:50PM +0530, Sai Prakash Ranjan wrote: > diff --git a/drivers/gpu/drm/msm/msm_iommu.c b/drivers/gpu/drm/msm/msm_iommu.c > index f455c597f76d..bd1d58229cc2 100644 > --- a/drivers/gpu/drm/msm/msm_iommu.c > +++ b/drivers/gpu/drm/msm/msm_iommu.c > @@ -218,6 +218,9 @@ static int msm_iommu_map(struct msm_mmu *mmu, uint64_t iova, > iova |= GENMASK_ULL(63, 49); > > > + if (mmu->features & MMU_FEATURE_USE_SYSTEM_CACHE) > + prot |= IOMMU_SYS_CACHE_ONLY; Given that I think this is the only user of IOMMU_SYS_CACHE_ONLY, then it looks like it should actually be a property on the domain because we never need to configure it on a per-mapping basis within a domain, and therefore it shouldn't be exposed by the IOMMU API as a prot flag. Do you agree? Will