From mboxrd@z Thu Jan 1 00:00:00 1970 From: Weidong Han Subject: Re: Xen VGA graphics passthrough for secondary adapters, vBAR=pBAR etc Date: Mon, 12 Apr 2010 17:57:11 +0800 Message-ID: <4BC2EE77.5010601@intel.com> References: <20100412072119.GW1878@reaktio.net> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: quoted-printable Return-path: In-Reply-To: <20100412072119.GW1878@reaktio.net> List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xensource.com Errors-To: xen-devel-bounces@lists.xensource.com To: =?ISO-8859-1?Q?Pasi_K=E4rkk=E4inen?= Cc: "xen-devel@lists.xensource.com" List-Id: xen-devel@lists.xenproject.org Pasi K=E4rkk=E4inen wrote: > Hello, > > Now that Xen 4.0.0 is out and has support for primary graphics passthru > and many people have been using it already and asking for a status upda= te > for secondary adapter passthru I thought of opening a new thread about = this. > > What are the actual issues that need to be resolved to get the=20 > secondary graphics passthru working? Probably related to VGA BIOS execu= tion > in the guest?=20 > =20 I think of two things need to be solved for secondary gfx assigned: 1) claim VGA cycle for it to display in VGA for guest, VGA is owned by=20 primary gfx. 2) load VGA bios from file, because you cannot get it from memory like=20 primary gfx. > How about the vBAR=3DpBAR stuff required for some (Nvidia) cards?=20 > How do we get that functionality integrated so people don't need additi= onal patches?=20 > =20 vBAR=3DpBAR patch is a bit tricky. It needs to cook a new clean vBAR=3DpB= AR=20 patch if integrate it in upstream. > Was there also a problem that a working VGA BIOS cannot be copied from = some cards=20 > and they need to use/load it from a file?=20 > =20 Load it from a file should work for all cards, but it's not user=20 friendly (involving manual steps). It's better to implement a generic=20 approach to get VGA bios for various gfx cards including primary and=20 secondary gfx. The direct way is to load it from expansion rom, but it=20 doesn't always work because expansion rom address may be invalid (the=20 bridge may doesn't have enough memory for gfx card). Regards, Weidong > Thanks! > > -- Pasi > > btw. I've created a wiki page where we can list all the tested/working = graphics adapters: > http://wiki.xensource.com/xenwiki/XenVGAPassthroughTestedAdapters > > > =20