From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:45927) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Z4QHj-0005bE-MG for qemu-devel@nongnu.org; Mon, 15 Jun 2015 05:02:28 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1Z4QHi-0006nh-Q1 for qemu-devel@nongnu.org; Mon, 15 Jun 2015 05:02:27 -0400 Received: from mx1.redhat.com ([209.132.183.28]:40909) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Z4QHi-0006n9-Kf for qemu-devel@nongnu.org; Mon, 15 Jun 2015 05:02:26 -0400 Message-ID: <557E949F.8070002@redhat.com> Date: Mon, 15 Jun 2015 12:02:23 +0300 From: Marcel Apfelbaum MIME-Version: 1.0 References: <1434029828-31954-1-git-send-email-marcel@redhat.com> <20150611135841.GA7998@morn.localdomain> <55799751.1030904@redhat.com> <20150611142425.GA10763@morn.localdomain> <55799CD6.1060506@redhat.com> <20150611165404.GB20655@morn.localdomain> <5579C959.8020607@redhat.com> <20150611191058.GA28252@morn.localdomain> <1434088832.28479.7.camel@redhat.com> <557ACDD7.9060801@redhat.com> <20150612132329.GB3622@morn.localdomain> <1434348068.31654.15.camel@redhat.com> <1434351024.31654.25.camel@gmail.com> In-Reply-To: <1434351024.31654.25.camel@gmail.com> Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 7bit Subject: Re: [Qemu-devel] [PATCH V2] pci: fixes to allow booting from extra root pci buses. List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Gerd Hoffmann , Kevin O'Connor Cc: seabios@seabios.org, lersek@redhat.com, qemu-devel@nongnu.org, mst@redhat.com On 06/15/2015 09:50 AM, Gerd Hoffmann wrote: > Hi, > >> I'm wondering whenever things become easier if we add config registers >> to the pxb, where the firmware can program the bus number range and we >> can use the config register base as a way to specify which pxb we are >> referring to ? > > ... and, while thinking about ben's reply elsewhere in this thread, > maybe even decouple the whole thing from the primary root bus? You > can't program the devices via 0x0cf8 then, but we could add a mmconfig > bar to the host bridge device ... Hi Gerd, I thought about it of course, but it seemed to me to be over-kill and no real reason to do it. I would hove done it if: - there would be a "generic" spec for such a host-bridge specifying at least the registers for the bus number. I didn't find anything => => Seabios should be aware of a special QEMU device and look for it... ugly - I would have seen how Seabios/coreboot program the above bus number. Again, didn't find the host-bridge programming code. At last, I followed a 'real' PXB device, some old Intel snooping host bridge. As always, I am open to ideas, but, the latest patches from Laszlo follows Seabios way, and if OVMF can also handle it maybe we can stop: "The use of logical bus number instead of bus index" discussion and start arguing on something else. :) I just want to say thank you to everybody involved, a lot of information and good guidelines surfaced during this talk. Until the next patch... Thanks, Marcel > > cheers, > Gerd > >