2 Commits

Author	SHA1	Message	Date
Laine Stump	c27b0bb171	qemu: fix handling of default/implicit devices for q35 ... This patch adds in special handling for a few devices that need to be treated differently for q35 domains: usb - there is no implicit/default usb controller for the q35 machinetype. This is done because normally the default usb controller is added to a domain by just adding "-usb" to the qemu commandline, and it's assumed that this will add a single piix3 usb1 controller at slot 1 function 2. That's not what happens when the machinetype is q35, though. Instead, adding -usb to the commandline adds 3 usb (version 2) controllers to the domain at slot 0x1D.{1,2,7}. Rather than having <controller type='usb' index='0'/> translate into 3 separate devices on the PCI bus, it's cleaner to not automatically add a default usb device; one can always be added explicitly if desired. Or we may decide that on q35 machines, 3 usb controllers will be automatically added when none is given. But for this initial commit, at least we aren't locking ourselves into something we later won't want. video - qemu always initializes the primary video device immediately after any integrated devices for the machinetype. Unless instructed otherwise (by using "-device vga..." instead of "-vga" which libvirt uses in many cases to work around deficiencies and bugs in various qemu versions) qemu will always pick the first unused slot. In the case of the "pc" machinetype and its derivatives, this is always slot 2, but on q35 machinetypes, the first free slot is slot 1 (since the q35's integrated peripheral devices are placed in other slots, e.g. slot 0x1f). In order to make the PCI address of the video device predictable, that slot (1 or 2, depending on machinetype) is reserved even when no video device has been specified. sata - a q35 machine always has a sata controller implicitly added at slot 0x1F, function 2. There is no way to avoid this controller, so we always add it. Note that the xml2xml tests for the pcie-root and q35 cases were changed to use DO_TEST_DIFFERENT() so that we can check for the sata controller being automatically added. This is especially important because we can't check for it in the xml2argv output (it has no effect on that output since it's an implicit device). ide - q35 has no ide controllers. isa and smbus controllers - these two are always present in a q35 (at slot 0x1F functions 0 and 3) but we have no way of modelling them in our config. We do need to reserve those functions so that the user doesn't attempt to put anything else there though. (note that the "pc" machine type also has an ISA controller, which we also ignore).	2013-08-05 15:47:49 -04:00
Laine Stump	48a3f48ac5	qemu: add pcie-root controller ... This controller is implicit on q35 machinetypes. It provides 31 PCIe (*not* PCI) slots as controller 0. Currently there are no devices that can connect to pcie-root, and no implicit pci controller on a q35 machine, so q35 is still unusable. For a usable q35 system, we need to add a "dmi-to-pci-bridge" pci controller, which can connect to pcie-root, and provides standard pci slots that can be used to connect other devices.	2013-08-05 15:13:56 -04:00