diff --git a/docs/qdev-device-use.txt b/docs/qdev-device-use.txt new file mode 100644 index 000000000..f252c8e3b --- /dev/null +++ b/docs/qdev-device-use.txt @@ -0,0 +1,353 @@ += How to convert to -device & friends = + +=== Specifying Bus and Address on Bus === + +In qdev, each device has a parent bus. Some devices provide one or +more buses for children. You can specify a device's parent bus with +-device parameter bus. + +A device typically has a device address on its parent bus. For buses +where this address can be configured, devices provide a bus-specific +property. These are + + bus property name value format + PCI addr %x.%x (dev.fn, .fn optional) + I2C address %u + SCSI scsi-id %u + +Example: device i440FX-pcihost is on the root bus, and provides a PCI +bus named pci.0. To put a FOO device into its slot 4, use -device +FOO,bus=/i440FX-pcihost/pci.0,addr=4. The abbreviated form bus=pci.0 +also works as long as the bus name is unique. + +Note: the USB device address can't be controlled at this time. + +=== Block Devices === + +A QEMU block device (drive) has a host and a guest part. + +In the general case, the guest device is connected to a controller +device. For instance, the IDE controller provides two IDE buses, each +of which can have up to two ide-drive devices, and each ide-drive +device is a guest part, and is connected to a host part. + +Except we sometimes lump controller, bus(es) and drive device(s) all +together into a single device. For instance, the ISA floppy +controller is connected to up to two host drives. + +The old ways to define block devices define host and guest part +together. Sometimes, they can even define a controller device in +addition to the block device. + +The new way keeps the parts separate: you create the host part with +-drive, and guest device(s) with -device. + +The various old ways to define drives all boil down to the common form + + -drive if=TYPE,index=IDX,bus=BUS,unit=UNIT,HOST-OPTS... + +TYPE, BUS and UNIT identify the controller device, which of its buses +to use, and the drive's address on that bus. Details depend on TYPE. +IDX is an alternative way to specify BUS and UNIT. + +In the new way, this becomes something like + + -drive if=none,id=DRIVE-ID,HOST-OPTS... + -device DEVNAME,drive=DRIVE-ID,DEV-OPTS... + +The -device argument differs in detail for each kind of drive: + +* if=ide + + -device ide-drive,drive=DRIVE-ID,bus=IDE-BUS,unit=UNIT + + where IDE-BUS identifies an IDE bus, normally either ide.0 or ide.1, + and UNIT is either 0 or 1. + + Bug: new way does not work for ide.1 unit 0 (in old terms: index=2) + unless you disable the default CD-ROM with -nodefaults. + +* if=scsi + + The old way implicitly creates SCSI controllers as needed. The new + way makes that explicit: + + -device lsi53c895a,id=ID + + As for all PCI devices, you can add bus=PCI-BUS,addr=DEVFN to + control the PCI device address. + + This SCSI controller a single SCSI bus, named ID.0. Put a disk on + it: + + -device scsi-disk,drive=DRIVE-ID,bus=ID.0,scsi-id=SCSI-ID + +* if=floppy + + -global isa-fdc,driveA=DRIVE-ID,driveB=DRIVE-ID + + This is -global instead of -device, because the floppy controller is + created automatically, and we want to configure that one, not create + a second one (which isn't possible anyway). + + Omitting a drive parameter makes that drive empty. + + Bug: driveA works only if you disable the default floppy drive with + -nodefaults. + +* if=virtio + + -device virtio-blk-pci,drive=DRIVE-ID,class=C,vectors=V + + This lets you control PCI device class and MSI-X vectors. + + As for all PCI devices, you can add bus=PCI-BUS,addr=DEVFN to + control the PCI device address. + +* if=pflash, if=mtd, if=sd, if=xen are not yet available with -device + +For USB devices, the old way is actually different: + + -usbdevice disk:format=FMT:FILENAME + +Provides much less control than -drive's HOST-OPTS... The new way +fixes that: + + -device usb-storage,drive=DRIVE-ID + +=== Character Devices === + +A QEMU character device has a host and a guest part. + +The old ways to define character devices define host and guest part +together. + +The new way keeps the parts separate: you create the host part with +-chardev, and the guest device with -device. + +The various old ways to define a character device are all of the +general form + + -FOO FOO-OPTS...,LEGACY-CHARDEV + +where FOO-OPTS... is specific to -FOO, and the host part +LEGACY-CHARDEV is the same everywhere. + +In the new way, this becomes + + -chardev HOST-OPTS...,id=CHR-ID + -device DEVNAME,chardev=CHR-ID,DEV-OPTS... + +The appropriate DEVNAME depends on the machine type. For type "pc": + +* -serial becomes -device isa-serial,iobase=IOADDR,irq=IRQ,index=IDX + + This lets you control I/O ports and IRQs. + +* -parallel becomes -device isa-parallel,iobase=IOADDR,irq=IRQ,index=IDX + + This lets you control I/O ports and IRQs. + +* -usbdevice serial:vendorid=VID,productid=PRID becomes + -device usb-serial,vendorid=VID,productid=PRID + +* -usbdevice braille doesn't support LEGACY-CHARDEV syntax. It always + uses "braille". With -device, this useful default is gone, so you + have to use something like + + -device usb-braille,chardev=braille,vendorid=VID,productid=PRID + -chardev braille,id=braille + +* -virtioconsole is still being worked on + +LEGACY-CHARDEV translates to -chardev HOST-OPTS... as follows: + +* null becomes -chardev null + +* pty, msmouse, braille, stdio likewise + +* vc:WIDTHxHEIGHT becomes -chardev vc,width=WIDTH,height=HEIGHT + +* vc:CxC becomes -chardev vc,cols=,rows= + +* con: becomes -chardev console + +* COM becomes -chardev serial,path= + +* file:FNAME becomes -chardev file,path=FNAME + +* pipe:FNAME becomes -chardev pipe,path=FNAME + +* tcp:HOST:PORT,OPTS... becomes -chardev socket,host=HOST,port=PORT,OPTS... + +* telnet:HOST:PORT,OPTS... becomes + -chardev socket,host=HOST,port=PORT,OPTS...,telnet=on + +* udp:HOST:PORT@LOCALADDR:LOCALPORT becomes + -chardev udp,host=HOST,port=PORT,localaddr=LOCALADDR,localport=LOCALPORT + +* unix:FNAME becomes -chardev socket,path=FNAME + +* /dev/parportN becomes -chardev parport,file=/dev/parportN + +* /dev/ppiN likewise + +* Any other /dev/FNAME becomes -chardev tty,path=/dev/FNAME + +* mon:LEGACY-CHARDEV is special: it multiplexes the monitor onto the + character device defined by LEGACY-CHARDEV. -chardev provides more + general multiplexing instead: you can connect up to four users to a + single host part. You need to pass mux=on to -chardev to enable + switching the input focus. + +QEMU uses LEGACY-CHARDEV syntax not just to set up guest devices, but +also in various other places such as -monitor or -net +user,guestfwd=... You can use chardev:CHR-ID in place of +LEGACY-CHARDEV to refer to a host part defined with -chardev. + +=== Network Devices === + +A QEMU network device (NIC) has a host and a guest part. + +The old ways to define NICs define host and guest part together. It +looks like this: + + -net nic,vlan=VLAN,macaddr=MACADDR,model=MODEL,name=ID,addr=STR,vectors=V + +Except for USB it looks like this: + + -usbdevice net:vlan=VLAN,macaddr=MACADDR,name=ID,addr=STR,vectors=V + +The new way keeps the parts separate: you create the host part with +-netdev, and the guest device with -device, like this: + + -netdev type=TYPE,id=NET-ID + -device DEVNAME,netdev=NET-ID,mac=MACADDR,DEV-OPTS... + +Unlike the old way, this creates just a network device, not a VLAN. +If you really want a VLAN, create it the usual way, then create the +guest device like this: + + -device DEVNAME,vlan=VLAN,mac=MACADDR,DEV-OPTS... + +DEVNAME equals MODEL, except for virtio you have to name the virtio +device appropriate for the bus (virtio-net-pci for PCI), and for USB +NIC you have to use usb-net. + +The old name=ID parameter becomes the usual id=ID with -device. + +For PCI devices, you can add bus=PCI-BUS,addr=DEVFN to control the PCI +device address, as usual. The old -net nic provides parameter addr +for that, it is silently ignored when the NIC is not a PCI device. + +-net nic accepts vectors=V for all models, but it's silently ignored +except for virtio-net-pci (model=virtio). With -device, only devices +that support it accept it. + +Not all devices are available with -device at this time. All PCI +devices and ne2k_isa are. + +Some PCI devices aren't available with -net nic, e.g. i82558a. + +Bug: usb-net does not work, yet. Patch posted. + +=== Graphics Devices === + +Host and guest part of graphics devices have always been separate. + +The old way to define the guest graphics device is -vga VGA. + +The new way is -device. Map from -vga argument to -device: + + std -device VGA + cirrus -device cirrus-vga + vmware -device vmware-svga + xenfb not yet available with -device + +As for all PCI devices, you can add bus=PCI-BUS,addr=DEVFN to control +the PCI device address. + +-device VGA supports properties bios-offset and bios-size, but they +aren't used with machine type "pc". + +Bug: -device cirrus-vga and -device vmware-svga require -nodefaults. + +Bug: the new way requires PCI; ISA VGA is not yet available with +-device. + +Bug: the new way doesn't work for machine type "pc", because it +violates obscure device initialization ordering constraints. + +=== Audio Devices === + +Host and guest part of audio devices have always been separate. + +The old way to define guest audio devices is -soundhw C1,... + +The new way is to define each guest audio device separately with +-device. + +Map from -soundhw sound card name to -device: + + ac97 -device AC97 + cs4231a -device cs4231a,iobase=IOADDR,irq=IRQ,dma=DMA + es1370 -device ES1370 + gus -device gus,iobase=IOADDR,irq=IRQ,dma=DMA,freq=F + sb16 -device sb16,iobase=IOADDR,irq=IRQ,dma=DMA,dma16=DMA16,version=V + adlib not yet available with -device + pcspk not yet available with -device + +For PCI devices, you can add bus=PCI-BUS,addr=DEVFN to control the PCI +device address, as usual. + +=== USB Devices === + +The old way to define a virtual USB device is -usbdevice DRIVER:OPTS... + +The new way is -device DEVNAME,DEV-OPTS... Details depend on DRIVER: + +* mouse -device usb-mouse +* tablet -device usb-tablet +* keyboard -device usb-kdb +* wacom-tablet -device usb-wacom-tablet +* host:... See "Host Device Assignment" +* disk:... See "Block Devices" +* serial:... See "Character Devices" +* braille See "Character Devices" +* net:... See "Network Devices" +* bt:... not yet available with -device + +=== Watchdog Devices === + +Host and guest part of watchdog devices have always been separate. + +The old way to define a guest watchdog device is -watchdog DEVNAME. +The new way is -device DEVNAME. For PCI devices, you can add +bus=PCI-BUS,addr=DEVFN to control the PCI device address, as usual. + +=== Host Device Assignment === + +QEMU supports assigning host PCI devices (qemu-kvm only at this time) +and host USB devices. + +The old way to assign a host PCI device is + + -pcidevice host=ADDR,dma=none,id=ID + +The new way is + + -device pci-assign,host=ADDR,iommu=IOMMU,id=ID + +The old dma=none becomes iommu=0 with -device. + +The old way to assign a host USB device is + + -usbdevice host:auto:BUS.ADDR:VID:PRID + +where any of BUS, ADDR, VID, PRID can be the wildcard *. + +The new way is + + -device usb-host,hostbus=BUS,hostaddr=ADDR,vendorid=VID,productid=PRID + +where left out or zero BUS, ADDR, VID, PRID serve as wildcard.