From owner-freebsd-x11@FreeBSD.ORG Tue Dec 25 23:38:18 2012 Return-Path: Delivered-To: freebsd-x11@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [69.147.83.52]) by hub.freebsd.org (Postfix) with ESMTP id DDE4E52B; Tue, 25 Dec 2012 23:38:18 +0000 (UTC) (envelope-from bas_vermin@hotmail.com) Received: from dub0-omc2-s12.dub0.hotmail.com (dub0-omc2-s12.dub0.hotmail.com [157.55.1.151]) by mx1.freebsd.org (Postfix) with ESMTP id 6ADDB8FC0A; Tue, 25 Dec 2012 23:38:18 +0000 (UTC) Received: from DUB002-W120 ([157.55.1.136]) by dub0-omc2-s12.dub0.hotmail.com with Microsoft SMTPSVC(6.0.3790.4675); Tue, 25 Dec 2012 15:37:10 -0800 X-EIP: [faafRZohAba2GVXqRJbj60NQGIiRr93u] X-Originating-Email: [bas_vermin@hotmail.com] Message-ID: From: Bas Vermin To: "freebsd-hackers@freebsd.org" , "freebsd-x11@freebsd.org" Subject: Your thoughts on a buffer sharing mechanism for FreeBSD (dma-buf for drm2) Date: Wed, 26 Dec 2012 00:37:10 +0100 Importance: Normal MIME-Version: 1.0 X-OriginalArrivalTime: 25 Dec 2012 23:37:10.0061 (UTC) FILETIME=[C22565D0:01CDE2F8] Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable X-Content-Filtered-By: Mailman/MimeDel 2.1.14 X-BeenThere: freebsd-x11@freebsd.org X-Mailman-Version: 2.1.14 Precedence: list List-Id: X11 on FreeBSD -- maintaining and support List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 25 Dec 2012 23:38:18 -0000 Hi Guys=2C Today I decided to do something useful for the FreeBSD community=2C working= on the TTM and KMS for the AMD graphics cards which I think a lot of peopl= e could use. As most of us know Intel KMS support was added to FreeBSD a few months ago= =2C and as far as I know this code was based on the Linux 3.1 kernel. The F= AQ in the wiki states that in order to keep this code up to date the Linux = commit log would be checked and changes merged into FreeBSD. Then came Linu= x 3.3 which added support for dma-buf=2C the buffer sharing mechanism to be= used by PRIME for offloading work to different GPU's=2C a feature we obvio= usly want. The problem with dma-buf is that it is licensed under the GPL an= d has now littered all over the otherwise MIT licensed drm code (even nVidi= a wasn't allowed to use dma-buf for their propietary driver). My question is=2C does such a buffer sharing mechanism exist in FreeBSD? And if so=2C would it be somewhat compatible with what dma-buf is doing in = the PRIME code? If not I think such a mechanism should be created=2C prehaps part of the vm= system (not separate as dma-buf is). Or am I just being stupid and is ther= e a much better way of solving this problem? I'd like your thoughts on this. Bas =