[PATCH 10/10] hw/arm/virt: Fix devicetree warnings about the virtio-iommu node

[Jean-Philippe Brucker]

dt-validate and dtc throw a few warnings when parsing the virtio-iommu
node:

  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
  pcie@10000000: virtio_iommu@16:compatible: ['virtio,pci-iommu'] does not 
contain items matching the given schema
  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"

The compatible property for a PCI child node should follow the rules
from "PCI Bus Binding to: IEEE Std 1275-1994". It should contain the
Vendor ID and Device ID (or class code).

The unit-name should be "device,function".

Signed-off-by: Jean-Philippe Brucker <jean-philippe@linaro.org>
---
Note that this doesn't follow
linux/Documentation/devicetree/bindings/virtio/iommu.txt, I'll update
that document when converting it to yaml, hopefully this Linux cycle.
The "virtio,pci-iommu" compatible string is not actually used by any
driver and only QEMU implements it, so we can get rid of it.
---
 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 de508d5329..08b79592eb 100644
--- a/hw/arm/virt.c
+++ b/hw/arm/virt.c
@@ -1374,14 +1374,15 @@ 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[] = "pci1af4,1057";
     uint16_t bdf = vms->virtio_iommu_bdf;
     MachineState *ms = MACHINE(vms);
     char *node;
 
     vms->iommu_phandle = qemu_fdt_alloc_phandle(ms->fdt);
 
-    node = g_strdup_printf("%s/virtio_iommu@%d", vms->pciehb_nodename, bdf);
+    node = g_strdup_printf("%s/virtio_iommu@%x,%x", vms->pciehb_nodename,
+                           PCI_SLOT(bdf), PCI_FUNC(bdf));
     qemu_fdt_add_subnode(ms->fdt, node);
     qemu_fdt_setprop(ms->fdt, node, "compatible", compat, sizeof(compat));
     qemu_fdt_setprop_sized_cells(ms->fdt, node, "reg",
-- 
2.37.1