On Mon, Oct 11, 2010 at 02:07:14PM +0200, Gerd Hoffmann wrote: > Hi, > > >Floppy? Yes, I think we do. > > And *one* floppy controllers can actually have *two* drives > connected, although booting from 'b' doesn't work IIRC. > > >>and since one PCI device may > >>control more then one disk (ATA slave/master, SCSI LUNs). We can do what > >>EDD specification does. Describe disk as: > >> bus type (isa/pci), > >> address on a bus (16 bit base address for isa, b/s/f for pci) > >> device type (ATA/SCSI/VIRTIO) > >> device path (slave/master for ATA, LUN for SCSI, nothing for virtio) > > > >If we had a qdev ID for all devices (which I think we should have > >anyway), would this work or is a string not really handy enough? > > I think we'll need support for that in all drivers supporting boot > anyway, i.e. have virtio-blk-pci register a boot edd when configured > that way. Question is how to configure this. We could attach the > boot index to either the blockdev or the device, i.e. > > -blockdev foo,bootindex=1 > > or > > -device virtio-blk-pci,bootindex=1 > > The latter looks more useful to me, boot order is guest state imho, > also it might expand to PXE booting nicely, i.e. > > -device e1000,bootindex=2 > Yes, boot order is a guest sate managed by BIOS on real HW.
> Which turns up the question how this plays with option roms. > seabios should be able to order at pci device level at least when > booting via (pci) option rom. OK for nics. Booting from a scsi > disk with id != 0 using the lsi rom is probably impossible though. > > What about non-pci option roms? The one used for -kernel for example? > -option-rom rom.bin,bootindex=3? We can pass boot index along with option rom via fw_cfg interface. -- Gleb.