On Fri, Feb 07, 2020 at 10:32:00AM +0100, Eric Auger wrote:
> At the moment, the kernel only supports device tree
> integration of the virtio-iommu. DT bindings between the
> PCI root complex and the IOMMU must be created by the machine
> in conformance to:
>
> Documentation/devicetree/bindings/virtio/iommu.txt.
>
> To make sure the end-user is aware of this, force him to use the
> temporary device option "x-dt-binding" and also double check the
> machine has a hotplug handler for the virtio-iommu-pci device.
> This hotplug handler is in charge of creating those DT bindings.
>
> Signed-off-by: Eric Auger <eric.au...@redhat.com>
> Suggested-by: Michael S. Tsirkin <m...@redhat.com>
how about setting it by default from machine class?
See
[PATCH 1/2] spapr: Disable legacy virtio devices for pseries-5.0 and later
[PATCH 2/2] spapr: Enable virtio iommu_platform=on by default
which does it for spapr.
> ---
>
> May be squashed with previous patch
> ---
> hw/virtio/virtio-iommu-pci.c | 18 ++++++++++++++++++
> 1 file changed, 18 insertions(+)
>
> diff --git a/hw/virtio/virtio-iommu-pci.c b/hw/virtio/virtio-iommu-pci.c
> index d539fcce75..3d06e14000 100644
> --- a/hw/virtio/virtio-iommu-pci.c
> +++ b/hw/virtio/virtio-iommu-pci.c
> @@ -14,6 +14,7 @@
> #include "virtio-pci.h"
> #include "hw/virtio/virtio-iommu.h"
> #include "hw/qdev-properties.h"
> +#include "qapi/error.h"
>
> typedef struct VirtIOIOMMUPCI VirtIOIOMMUPCI;
>
> @@ -27,10 +28,12 @@ typedef struct VirtIOIOMMUPCI VirtIOIOMMUPCI;
> struct VirtIOIOMMUPCI {
> VirtIOPCIProxy parent_obj;
> VirtIOIOMMU vdev;
> + bool dt_binding;
> };
>
> static Property virtio_iommu_pci_properties[] = {
> DEFINE_PROP_UINT32("class", VirtIOPCIProxy, class_code, 0),
> + DEFINE_PROP_BOOL("x-dt-binding", VirtIOIOMMUPCI, dt_binding, false),
> DEFINE_PROP_END_OF_LIST(),
> };
>
> @@ -39,6 +42,21 @@ static void virtio_iommu_pci_realize(VirtIOPCIProxy
> *vpci_dev, Error **errp)
> VirtIOIOMMUPCI *dev = VIRTIO_IOMMU_PCI(vpci_dev);
> DeviceState *vdev = DEVICE(&dev->vdev);
>
> + if (!dev->dt_binding) {
> + error_setg(errp,
> + "Instantiation currently only is possible if the machine "
> + "creates device tree iommu-map bindings, ie. ACPI is not "
> + "yet supported");
> + error_append_hint(errp, "use -virtio-iommu-pci,x-dt-binding\n");
> + return;
> + }
> +
> + if (!qdev_get_machine_hotplug_handler(DEVICE(vpci_dev))) {
> + error_setg(errp,
> + "The machine does not implement a virtio-iommu-pci
> hotplug "
> + " handler that creates the device tree iommu-map
> bindings");
> + return;
> + }
> qdev_set_parent_bus(vdev, BUS(&vpci_dev->bus));
> object_property_set_link(OBJECT(dev),
> OBJECT(pci_get_bus(&vpci_dev->pci_dev)),
> --
> 2.20.1
