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=-1.1 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_PASS 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 B9501C46471 for ; Tue, 7 Aug 2018 09:18:32 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 5C69021477 for ; Tue, 7 Aug 2018 09:18:32 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=flowbird.group header.i=@flowbird.group header.b="rT+T+aaB" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 5C69021477 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=flowbird.group 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 S1732952AbeHGLby (ORCPT ); Tue, 7 Aug 2018 07:31:54 -0400 Received: from mail-wm0-f41.google.com ([74.125.82.41]:36641 "EHLO mail-wm0-f41.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727011AbeHGLbx (ORCPT ); Tue, 7 Aug 2018 07:31:53 -0400 Received: by mail-wm0-f41.google.com with SMTP id w24-v6so17234960wmc.1 for ; Tue, 07 Aug 2018 02:18:28 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=flowbird.group; s=google; h=subject:to:cc:references:from:message-id:date:user-agent :mime-version:in-reply-to:content-transfer-encoding:content-language; bh=nHBB1ieJms544607CR4nPIWKqqaclU3eAACV5U7SvbM=; b=rT+T+aaB7vK8g4yTeFWuDx/Awzeg6fE22CSmnp9f1IjimxlYq7+usETo+F8/7MsAix 6XDBEFOyROFjEnq3RxTHXszxlTzv5x4RfB0MGjRtct02WLG7uadJ320+GOEFbc0gvHil iMYkgTyDeMOAyWiNKPTGScoL4/9FL2a3ZDgbsRh0l8OsUOuJJHANGgeovWJbhGr4Sis7 Ow1apufm4OnUMsx8v/I16YlcZh128LyN8hNhn/RDtOVBUMK8Fwlj+Zs5RW91mzgINlAD tJptEqfKti+ptqHOZ7ow8cdzj6us4rcIWrR96C/IWoEdG/OCTT7ZFvcLqUT+kJzg1pX1 8+nQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:subject:to:cc:references:from:message-id:date :user-agent:mime-version:in-reply-to:content-transfer-encoding :content-language; bh=nHBB1ieJms544607CR4nPIWKqqaclU3eAACV5U7SvbM=; b=m1G1vO3nvQUKu57AKOmLd+18cJYEIphwN4KkuEpZnf1ixQTGwxJqbbdQAw5quiv1c0 qusldheeoXmZUXraUrp9enkx7Kb8eWurpVmtDcYttc4UZjL0NJzS3Cmzoxt4Hbhb07Cv Z9XK/Z32nMRumJCowJT9Brjd0X7AIZO7dENzrSF8dtdGL0xsjb8VrRvzmZidLnbO9CSY 62ISbAS8OLwed8hQHZZDakxps1CgunU5eybkkdRGM5diJXVkjzLQ6PjEqeowfxN6EJA3 JF7yiyJbB4BmjBVeGCCgKyCLmh0VqQ8UmqHgiJR1J39f/rFDu7ja4nK7ucK52rnFPc+/ hdEw== X-Gm-Message-State: AOUpUlHNOtCzXcG2P+pumuRDtzBkjEC23ZswuNGuv/0PYQPVOtmZuGbz 27WVwOXtoY8y7aHWdc5mtVUoYg== X-Google-Smtp-Source: AA+uWPxqCmQ7MBEBtRRglSiYvCgcYNx/hVbmtKYsaP0+JVQvxN0NFkHiADhBPDqLsIF6pMu/ry36eA== X-Received: by 2002:a1c:aa0c:: with SMTP id t12-v6mr1044883wme.109.1533633508130; Tue, 07 Aug 2018 02:18:28 -0700 (PDT) Received: from [10.32.50.237] ([185.149.63.251]) by smtp.gmail.com with ESMTPSA id h14-v6sm1268989wro.15.2018.08.07.02.18.26 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Tue, 07 Aug 2018 02:18:27 -0700 (PDT) Subject: Re: [RFC] drm: Allow DRM_IOCTL_MODE_MAP_DUMB for render nodes To: Rob Herring , Sean Paul Cc: Emil Velikov , Robert Foss , David Airlie , Brian Paul , dri-devel , eric.engestrom@intel.com, Gustavo Padovan , "linux-kernel@vger.kernel.org" , Maarten Lankhorst , norvez@chromium.org, Tomasz Figa , Tomeu Vizoso References: <20180724082213.25677-1-robert.foss@collabora.com> <20180803195025.GO20303@art_vandelay> From: Martin Fuzzey Message-ID: <86334106-46d3-9d77-4c65-a1437e0454e5@flowbird.group> Date: Tue, 7 Aug 2018 11:18:26 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101 Thunderbird/52.9.1 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 7bit Content-Language: fr Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 06/08/18 21:05, Rob Herring wrote: > On Fri, Aug 3, 2018 at 1:50 PM Sean Paul wrote: >> Fwiw, I'd lean towards allowing DUMB allocation from the render nodes. I >> understand it limits use cases that are undesirable, but it is also limiting >> usecases that are desirable. So, given that people are going to get "creative" >> regardless of how many safety railings we put up, we shouldn't make things >> unnecessarily hard on other trying to Get Work Done. > The problem with using render nodes is what if there isn't one? We > require VGEM (and make VGEM allow dumb buffers) in that case? Try to open the render node and fall back to the card node if it doesn't exist? AFAICT VGEM doesn't provide contiguous buffers so it won't work for the imx-drm case. Regards, Martin