Re: [Qemu-devel] OVMF, Q35 and USB keyboard/mouse

[Gerd Hoffmann]

  Hi,

> OK, so I forgot to articulate that with the above patch, I'm seeing
> *both* uhci2 and uhci3, but not uhci1. Basically, if uhciX has an
> irq_pin less than 2, it won't show up in OSX if booted with ovmf.
> We're no longer looking at PIIX, this is q35 with ovmf or without.

Can you test what happens with piix4 + usb2?  (I suspect you can't as
osx will simply not boot then due to the piix4 being much older than the
intel port of osx).

I think ovmf simply doesn't get the IRQ routing right (doesn't
initialize PCI_INTERRUPT_LINE register correctly).  It is *not* the same
on piix and q35.  See piix_pci_slot_get_irq vs. mch_pci_slot_get_irq in
seabios source code.

I think if you boot linux guests with "noacpi" it will have trouble with
usb interrupts too.

cheers,
  Gerd