From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Michael S. Tsirkin" Subject: Re: [virtio-dev] Re: [PATCH] Add virtio gpu driver. Date: Thu, 26 Mar 2015 17:47:09 +0100 Message-ID: <20150326174401-mutt-send-email-mst@redhat.com> References: <20150325162246-mutt-send-email-mst@redhat.com> <1427297836.23304.29.camel@nilsson.home.kraxel.org> <20150325180721-mutt-send-email-mst@redhat.com> <1427353959.9779.2.camel@nilsson.home.kraxel.org> <20150326091545-mutt-send-email-mst@redhat.com> <1427359367.9779.9.camel@nilsson.home.kraxel.org> <20150326095736-mutt-send-email-mst@redhat.com> <1427369923.9779.18.camel@nilsson.home.kraxel.org> <20150326124751-mutt-send-email-mst@redhat.com> <1427382436.8786.15.camel@nilsson.home.kraxel.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Content-Disposition: inline In-Reply-To: <1427382436.8786.15.camel-3OfP5uLMi4C46o+2HkPkLj4oCIwMql/M@public.gmane.org> Sender: linux-api-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Gerd Hoffmann Cc: virtio-dev-sDuHXQ4OtrM4h7I2RyI4rWD2FQJk+8+b@public.gmane.org, Dave Airlie , Dave Airlie , David Airlie , Rusty Russell , open list , "open list:DRM DRIVERS" , "open list:VIRTIO CORE, NET..." , "open list:ABI/API" List-Id: linux-api@vger.kernel.org On Thu, Mar 26, 2015 at 04:07:16PM +0100, Gerd Hoffmann wrote: > Hi, > > > I don't know. This seems exactly like the kind of thing > > we had in mind when we added the virtio pci capability. > > For example, we have text in spec that requires drivers > > to skip unknown capabilities. > > > > And yes, if bios pokes at a specific bar then we do > > need to list this info in the virtio spec so this makes > > it an issue that is virtio related. > > Hmm, virtio-vga is a two-in-one device basically. When virtio is > enabled it behaves like virtio-gpu-pci, otherwise it behaves very > simliar to stdvga. So you need to know nothing about virtio to handle > the vga side, and I want keep it that way. > > When no vga compatibility is needed there always is the option to just > use virtio-gpu-pci instead. > > > Yes, it's not about what we put there now. It's about being able > > to move things about in the future without breaking guests. > > We don't have that today for stdvga, and I still fail to see what this > buys us. > > > Completely different thing crossing my mind: I think we can make > virtio-vga fully compatible with stdvga. stdvga has two bars, memory > (#0) and mmio (#2). We can make the mmio bar larger and place all the > virtio regions there. > Full compatibility with some standard sounds like a better motivation, yes. > > I think in any case I'll go split off the vga compatibility bits to a > different patch (and possible a separate patch series). > > cheers, > Gerd Will you still need me to change core to claim specific memory only? -- MST