From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:35931) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1brTvG-0006Sa-82 for qemu-devel@nongnu.org; Tue, 04 Oct 2016 13:54:35 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1brTvB-0001hX-5a for qemu-devel@nongnu.org; Tue, 04 Oct 2016 13:54:33 -0400 Received: from mx1.redhat.com ([209.132.183.28]:59194) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1brTvA-0001hK-V5 for qemu-devel@nongnu.org; Tue, 04 Oct 2016 13:54:29 -0400 References: <1472736127-18137-1-git-send-email-marcel@redhat.com> <6c9103e7-70ad-55c6-5533-d6d9bbaa39b4@redhat.com> <20161004145911.GA2155@redhat.com> <2ea37764-7787-0b1b-5abb-9f8ba12a7080@redhat.com> <2db6a14f-731d-422d-a928-a856360406fd@redhat.com> From: Laine Stump Message-ID: <02c5ce65-3941-7816-f533-c8d6bc85073e@redhat.com> Date: Tue, 4 Oct 2016 13:54:26 -0400 MIME-Version: 1.0 In-Reply-To: <2db6a14f-731d-422d-a928-a856360406fd@redhat.com> Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 7bit Subject: Re: [Qemu-devel] [PATCH RFC] docs: add PCIe devices placement guidelines List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org Cc: Laszlo Ersek , "Daniel P. Berrange" , Marcel Apfelbaum , Peter Maydell , Drew Jones , mst@redhat.com, Andrea Bolognani , Alex Williamson , Gerd Hoffmann On 10/04/2016 12:10 PM, Laine Stump wrote: > On 10/04/2016 11:40 AM, Laszlo Ersek wrote: >> Small correction to your wording though: you don't want to attach the >> DMI-PCI bridge to the PXB device, but to the extra root bus provided by >> the PXB. > > This made me realize something - the root bus on a pxb-pcie controller > has a single slot and that slot can accept either a pcie-root-port > (ioh3420) or a dmi-to-pci-bridge. If you want to have both express and > legacy PCI devices on the same NUMA node, then you would either need to > create one pxb-pcie for the pcie-root-port and another for the > dmi-to-pci-bridge, or you would need to put the pcie-root-port and > dmi-to-pci-bridge onto different functions of the single slot. Should > the latter work properly? We were discussing pxb-pcie today while Dan was trying to get a particular configuration working, and there was some disagreement about two points that I stated above as fact (but which may just be misunderstanding again): 1) Does pxb-pcie only provide a single slot (0)? Or does it provide 32 slots (0-31) just like the pcie root complex? 2) can you really only plug a pcie-root-port (ioh3420) into a pxb-pcie? Or will it accept anything that pcie.0 accepts?