[PATCH v2] docs: Document reserved PCI addresses for QEMU

in QEMU. Let's document them in one place, it's easier than reconstructing the list from the code each time. Signed-off-by: Michal Privoznik <mprivozn(a)redhat.com&gt; --- diff to v1: - All Laine's comment worked in, hopefully. docs/pci-addresses.rst | 50 ++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 50 insertions(+) diff --git a/docs/pci-addresses.rst b/docs/pci-addresses.rst index 885d50517a..4f123c7eb9 100644 --- a/docs/pci-addresses.rst +++ b/docs/pci-addresses.rst @@ -235,3 +235,53 @@ guest OS rather than as ``0001:08:00.1``, which is the address of the device on the host. Of course, all the rules and behaviors described above still apply. + + +Reserved addresses +================== + +Due to some historical reasons hypervisors might expect some PCI +devices to appear at certain addresses instead of 'random' ones. +For QEMU this is machine type and guest architecture dependant. +But to give you at least a gist here is list of reserved PCI +addresses: + +For ``I440FX`` the following devices are hard coded into QEMU and can't be +moved or eliminated: + +============ ====================== +0000:00:00.0 Host bridge +0000:00:01.0 ISA bridge +0000:00:01.1 primary IDE controller +0000:00:01.2 PIIX3 USB controller +0000:00:01.3 ACPI (power management) and SMBus controller +============ ====================== + +The following addresses will be used as default ones for the corresponding +devices (if the address is free or a different address wasn't provided for the +device): + +============ ================== +0000:00:02.0 primary video card +============ ================== + + +For ``Q35`` the following devices are hard coded into QEMU and can't be moved +or eliminated: + +============ ======================= +0000:00:00.0 Host bridge +0000:00:1f.2 primary SATA controller +0000:00:1f.0 ISA bridge +0000:00:1f.3 SMBus +============ ======================= + +The following addresses will be used as default ones for the corresponding +devices (if the address is free or a different address wasn't provided for the +device) because that's how real ``Q35`` would do it: + +============ =============== +0000:00:1a.0 USB2 controller +0000:00:1b.0 ICH9 sound chip +0000:00:1d.0 USB2 controller +============ =============== -- 2.25.3