Re: [PATCH v2 7/8] hw/arm/virt: Fix devicetree warnings about the virtio-iommu node

[Peter Maydell <peter.maydell@linaro.org>]

On Tue, 27 Sept 2022 at 11:12, Jean-Philippe Brucker
<jean-philippe@linaro.org> wrote:
>
> The "PCI Bus Binding to: IEEE Std 1275-1994" defines the compatible
> string for a PCIe bus or endpoint as "pci<vendorid>,<deviceid>" or
> similar. Since the initial binding for PCI virtio-iommu didn't follow
> this rule, it was modified to accept both strings and ensure backward
> compatibility. Also, the unit-name for the node should be
> "device,function".
>
> Fix corresponding dt-validate and dtc warnings:
>
>   pcie@10000000: virtio_iommu@16:compatible: ['virtio,pci-iommu'] does not contain items matching the given schema
>   pcie@10000000: Unevaluated properties are not allowed (... 'virtio_iommu@16' were unexpected)
>   From schema: linux/Documentation/devicetree/bindings/pci/host-generic-pci.yaml
>   virtio_iommu@16: compatible: 'oneOf' conditional failed, one must be fixed:
>         ['virtio,pci-iommu'] is too short
>         'pci1af4,1057' was expected
>   From schema: dtschema/schemas/pci/pci-bus.yaml
>
>   Warning (pci_device_reg): /pcie@10000000/virtio_iommu@16: PCI unit address format error, expected "2,0"
>
> Signed-off-by: Jean-Philippe Brucker <jean-philippe@linaro.org>
> ---
>  hw/arm/virt.c | 5 +++--
>  1 file changed, 3 insertions(+), 2 deletions(-)
>
> diff --git a/hw/arm/virt.c b/hw/arm/virt.c
> index 2de16f6324..5e16d54bbb 100644
> --- a/hw/arm/virt.c
> +++ b/hw/arm/virt.c
> @@ -1372,14 +1372,15 @@ static void create_smmu(const VirtMachineState *vms,
>
>  static void create_virtio_iommu_dt_bindings(VirtMachineState *vms)
>  {
> -    const char compat[] = "virtio,pci-iommu";
> +    const char compat[] = "virtio,pci-iommu\0pci1af4,1057";
>      uint16_t bdf = vms->virtio_iommu_bdf;

PCI_DEVICE_ID_VIRTIO_IOMMU is listed in include/hw/pci/pci.h
as 0x1014, so where does 1057 come from? (This is a hex value,
right?)

docs/specs/pci-ids.txt doesn't list either 1014 or 1057, so
I guess we forgot to update that...

thanks
-- PMM