On Mo, 2016-03-07 at 14:41 -0700, Alex Williamson wrote:
> On Fri, 4 Mar 2016 09:41:53 +0100
> Gerd Hoffmann <kra...@redhat.com> wrote:
>
> > Basically skip the lpc quirks with -M q35.
> > Applies on top of the vfio-igd patch series by alex.
> >
> > Signed-off-by: Gerd Hoffmann <kra...@redhat.com>
> > ---
> > hw/vfio/pci-quirks.c | 15 +++++++++++++++
> > 1 file changed, 15 insertions(+)
> >
> > diff --git a/hw/vfio/pci-quirks.c b/hw/vfio/pci-quirks.c
> > index 5828362..1757e3d 100644
> > --- a/hw/vfio/pci-quirks.c
> > +++ b/hw/vfio/pci-quirks.c
> > @@ -12,6 +12,7 @@
> >
> > #include "qemu/osdep.h"
> > #include "hw/nvram/fw_cfg.h"
> > +#include "hw/i386/ich9.h"
> > #include "pci.h"
> > #include "trace.h"
> > #include "qemu/range.h"
> > @@ -1410,6 +1411,7 @@ int vfio_pci_igd_lpc_init(VFIOPCIDevice *vdev,
> > struct vfio_region_info *region)
> > {
> > DeviceClass *dc = DEVICE_GET_CLASS(vdev);
> > + PCIBus *bus;
> > PCIDevice *lpc_bridge;
> > int ret;
> >
> > @@ -1423,6 +1425,19 @@ int vfio_pci_igd_lpc_init(VFIOPCIDevice *vdev,
> >
> > dc->hotpluggable = false;
> >
> > + bus = pci_device_root_bus(&vdev->pdev);
> > + lpc_bridge = pci_find_device(bus, 0, PCI_DEVFN(0x1f, 0));
> > + if (lpc_bridge) {
> > + const char *type = object_get_typename(OBJECT(lpc_bridge));
> > + if (strcmp(type, TYPE_ICH9_LPC_DEVICE) == 0) {
> > + /*
> > + * q35 lpc present, leave it as-is.
> > + * linux kernel 4.5+ can deal with this.
>
> What about anything older? I assume we want to support current
> distributions. Based on this patch it seems like we also want to test
> first if the lpc device is present, create it if not, then probably
> copy host data into it. Thanks,
q35 already has a isa bridge @ 1f.0, and it's not a dummy device but
emulates the ich9 lpc. Just overwriting the identity of that device
isn't a good idea I think.
cheers,
Gerd
