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=-2.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS,USER_AGENT_NEOMUTT 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 B860DC433F5 for ; Wed, 5 Sep 2018 06:10:45 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 729E12075E for ; Wed, 5 Sep 2018 06:10:45 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 729E12075E Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com 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 S1727534AbeIEKjQ (ORCPT ); Wed, 5 Sep 2018 06:39:16 -0400 Received: from mx3-rdu2.redhat.com ([66.187.233.73]:58540 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1726426AbeIEKjQ (ORCPT ); Wed, 5 Sep 2018 06:39:16 -0400 Received: from smtp.corp.redhat.com (int-mx05.intmail.prod.int.rdu2.redhat.com [10.11.54.5]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 1EA5787A72; Wed, 5 Sep 2018 06:10:42 +0000 (UTC) Received: from sirius.home.kraxel.org (ovpn-116-66.ams2.redhat.com [10.36.116.66]) by smtp.corp.redhat.com (Postfix) with ESMTP id D17E5B27AE; Wed, 5 Sep 2018 06:10:41 +0000 (UTC) Received: by sirius.home.kraxel.org (Postfix, from userid 1000) id 2090C16E08; Wed, 5 Sep 2018 08:10:41 +0200 (CEST) Date: Wed, 5 Sep 2018 08:10:41 +0200 From: Gerd Hoffmann To: Ilia Mirkin Cc: Michel =?utf-8?Q?D=C3=A4nzer?= , David Airlie , Sean Paul , dri-devel , open list Subject: Re: [PATCH 3/5] drm: fix drm_mode_addfb() on big endian machines. Message-ID: <20180905061041.7yfmvnpbnbugboc4@sirius.home.kraxel.org> References: <20180903105756.24912-1-kraxel@redhat.com> <20180903105756.24912-4-kraxel@redhat.com> <20180903164558.GL21634@phenom.ffwll.local> <8e8f8cf3-c4d4-6bfd-4e53-536d4d0c79ff@daenzer.net> <4262e9d1-75c9-1be3-08bd-1ef842a13f2f@daenzer.net> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: NeoMutt/20180716 X-Scanned-By: MIMEDefang 2.79 on 10.11.54.5 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.11.55.1]); Wed, 05 Sep 2018 06:10:42 +0000 (UTC) X-Greylist: inspected by milter-greylist-4.5.16 (mx1.redhat.com [10.11.55.1]); Wed, 05 Sep 2018 06:10:42 +0000 (UTC) for IP:'10.11.54.5' DOMAIN:'int-mx05.intmail.prod.int.rdu2.redhat.com' HELO:'smtp.corp.redhat.com' FROM:'kraxel@redhat.com' RCPT:'' Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi, > >>> As explained before, that would break radeon userspace on big endian hosts. > >> > >> We last discussed this about a year ago, so I hope you'll forgive my > >> lapse in memory... > >> > >> There's userspace that uses ADDFB2 with DRM_FORMAT_XRGB8888 but > >> expects it to be host-endian? > > > > ADDFB, not ADDFB2. The latter probably didn't even exist yet when this > > was made to work. :) > > Right, but ADDFB doesn't know or care about DRM_FORMAT_*. That's what > I'm saying -- keep ADDFB working, and fix up the DRM_FORMAT_* > underneath it both in the conversion and in the driver. Gerd's patch > allows us to do this incrementally, eventually truing up the > DRM_FORMAT_* in the driver, enabling ADDFB2 to work as expected. If it is that simple then yes, we should be able to fix the radeon kms driver, then drop the quirk once all kms drivers are fixed. But IIRC there are some radeon-sepcific calls used by the radeon xorg driver affected too (thats why the commit message says "... both xorg and kernel drivers ..."), so fixing it for radeon isn't that easy ... cheers, Gerd