On Tue, 2017-01-31 at 21:34 +0100, Gerd Hoffmann wrote: > > docs/q35-chipset.cfg | 152 > >------------------------------------------------ > > Please leave q35-chipset.cfg there. > > The purpose of q35-chipset.cfg is to document how you can build a > virtual machine which comes as close as possible to physical hardware > with q35 northbridge and ich9 southbridge. So it is pretty much > fixed ;) Maybe it makes sense to add a comment at the top clarifying > this. The (currently commented out) pcie switch configuration can be > dropped or moved to another file. And maybe we can add the ethernet > device meanwhile (has the e1000e emulation a ich9 device?). > > Adding another sample config focusing on pcie and good performance is > perfectly fine of course.
Gotcha. I'll try to get this file in line with the new ones where it comes to structure and add comments without messing with its purpose. > > docs/q35-graphical.cfg | 154 > >+++++++++++++++++++++++++++++++++++++++++++++++++ > > docs/q35-serial.cfg | 110 +++++++++++++++++++++++++++++++++++ > > Note that you can specify -readconfig multiple times, so you can split > out common stuff and ask people to run "qemu -readconfig > q35-paravirt-base.cfg -readconfig q35-paravirt-$style.cfg" Oh, I didn't know that! How about q35-emulated.cfg # emulated guest q35-virtio-common.cfg # shared by all VirtIO guests q35-virtio-graphical.cfg # VirtIO guest, graphical console q35-virtio-serial.cfg # VirtIO guest, serial console > > +# PCIe controllers > > +# ========================================================= > > +# > > +# We create four PCIe Root Ports: the first three are used > > +# by devices defined below, while the last one is left > > +# unused so that one more device can be hotplugged. > > + > > +[device "pci.1"] > > + driver = "ioh3420" > > + bus = "pcie.0" > > + addr = "0x2" > > + port = "0x10" > > + chassis = "1" > > I'd suggest to create 8 pcie root ports, as multifunction device in a > single slot, following pcie.txt suggestions. > > And I'd pick slot 1c for that, simply because the pcie root ports are in > that slot on physical hardware, but that is just cosmetic and a matter > of taste. Okay. > > +[device "usb"] > > + driver = "nec-usb-xhci" > > + bus = "pci.3" > > + addr = "0x0" > > Good, needs promotion ;) Eheh :) > > +[device "keyboard"] > > + driver = "usb-kbd" > > + bus = "usb.0" > > + port = "1" > > We have a ps/2 keyboard anyway, so this is pointless (on x86, arm is a > different story of course). Okay. I will add a comment about why this is the case. > > +[device "tablet"] > > + driver = "usb-tablet" > > + bus = "usb.0" > > + port = "2" > > There is also virtio-tablet, but for a generic config usb is probably > the better choice as virtio-tablet is supported by modern linux only (on > x86, on arm we have only modern linux anyway so picking virtio-tablet > should be fine). Okay, I will keep this in mind when working on the aarch64/virt sample configuration. We can probably use virtio-keyboard-pci and virtio-tablet-pci there, avoiding the need to have a USB controller at all. > > +# Video card > > +# ========================================================= > > +# > > +# We plug the QXL video card directly into the PCIe Root > > +# Bus as it is a legacy PCI device; this way, we can reduce > > +# the number of PCIe controllers in the guest. > > + > > +[device "video"] > > + driver = "qxl-vga" > > + bus = "pcie.0" > > + addr = "0x1" > > Note that you can put multiple devices into a single root port, using > multifunction. I have a guest here which looks like this: > > root@localhost ~# lspci -vt > -[0000:00]-+-00.0 Intel Corporation 82G33/G31/P35/P31 Express DRAM > Controller > +-02.0 Device 1234:1111 > +-1b.0 Intel Corporation 82801I (ICH9 Family) HD Audio > Controller > +-1c.0-[01]----00.0 Red Hat, Inc Virtio SCSI > +-1c.1-[02]----00.0 Red Hat, Inc Virtio network device > +-1c.2-[03]-- > +-1c.3-[04]-- > +-1c.4-[05]--+-00.0 Red Hat, Inc Virtio console > | +-00.1 Red Hat, Inc Virtio memory balloon > | \-00.2 Red Hat, Inc Virtio input > +-1c.5-[06]----00.0 NEC Corporation uPD720200 USB 3.0 Host > Controller > +-1c.6-[07]-- > +-1c.7-[08]-- > +-1e.0-[09-0a]----00.0-[0a]-- > +-1f.0 Intel Corporation 82801IB (ICH9) LPC Interface > Controller > +-1f.2 Intel Corporation 82801IR/IO/IH (ICH9R/DO/DH) 6 port > SATA Controller [AHCI mode] > \-1f.3 Intel Corporation 82801I (ICH9 Family) SMBus > Controller Mh, I think it's less confusing to only share a single port between devices when the devices in question are of the same type, ie. ioh3420s. So I'd rather leave this as it is. -- Andrea Bolognani / Red Hat / Virtualization
