From mboxrd@z Thu Jan 1 00:00:00 1970 From: Weidong Han Subject: Re: RE: Help needed on gfx-passthrough Date: Fri, 19 Mar 2010 14:21:28 +0800 Message-ID: <4BA317E8.3080606@intel.com> References: <201003181029.11631.dietmar.hahn@ts.fujitsu.com> <1A42CE6F5F474C41B63392A5F80372B21D5F3A28@shsmsx501.ccr.corp.intel.com> <201003181119.32389.dietmar.hahn@ts.fujitsu.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-15; format=flowed Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <201003181119.32389.dietmar.hahn@ts.fujitsu.com> List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xensource.com Errors-To: xen-devel-bounces@lists.xensource.com To: Dietmar Hahn Cc: "xen-devel@lists.xensource.com" List-Id: xen-devel@lists.xenproject.org Dietmar Hahn wrote: > Am 18.03.2010 schrieb Han, Weidong: > >> There is a wiki page for xen gfx passthru: http://wiki.xensource.com/xenwiki/XenVGAPassthrough. pls read it. >> > > Yes I did this. > > >> I didn't try your gfx card. As you know, some vbios of nVidia gfx cards have vbios re-execution issue, which results in no display in VGA mode. >> > > Yes I read this on the mailing list, you mean FLR issues? > Not exactly. Another possibility is that vbios bits may be truncated or modified after initialization in host, thus it might result in re-execution issue. >> You can have a try with loading vbios from file and make vBAR = pBAR. You can find the corresponding patches in xen-devel mailing list. >> > > I tried this already. > I want to look a little bit deeper to understand whats going on. > I saw your igd_passthru patch qemu hw/pci.c for special handling of some > pci config registers of the host bridge and maybe I need a similar patch > for the special PCI Express Graphics Port bridge. > Discrete gfx card is an independent pci device. I don't think it will depend on platform. IGD is integrated in chipset, and there are some dependencies on chipset. > My problem is that I don't see any access to extended config registers. > PCIe extended config registers (>256bytes) are not virtualized in Xen qemu. > Therefore my question for help in debugging to see what the vgabios is doing. > I don't know how to see what vgabios is doing. If you can find the vgabios engineer, maybe you can dump and send gfx register values to him for analysis. Regards, Weidong > Thanks. > Dietmar. > >> Regards, >> Weidong >> >> >> -----Original Message----- >> From: Dietmar Hahn [mailto:dietmar.hahn@ts.fujitsu.com] >> Sent: Thursday, March 18, 2010 5:29 PM >> To: xen-devel@lists.xensource.com >> Cc: Han, Weidong >> Subject: Help needed on gfx-passthrough >> >> Hi list, >> >> I try to get gfx-passthrough on a laptop: >> Intel PM45 Express chipset with extern nvidia craphics card G96M [Quadro FX 770M] >> I can't see the bios boot messages and also not the grub boot loader. >> The domU linux boot messages appear on the screen. >> >> For me it looks like the vgabios gets not started or works not well. >> In the domU I can read the vgabios from /dev/mem and it's the same as in dom0. >> If I change the hvmloader to use the standard vgabios from firmware/vgabios >> I see the bios and grub boot messages. >> >> I added some tracing to qemu-dm (pt_*read/write and pci_*read/write) to see >> accesses to the emulated chipset and graphics card but I can see no difference >> between using the original vgabios or the emulated vgabios within the hvmloader. >> >> Now my question: how can I debug this problem. How can I see whether the vgabios >> gets started and initialises the graphics card? >> I'am not fit enough in this area and documentation is very rare! >> Thanks in advance! >> >> Dietmar. >> >> >>