On Thu, Sep 8, 2022 at 8:05 AM Dan Williams <dan.j.williams@xxxxxxxxx> wrote: > > Robert Richter wrote: > > A lookup of a host bridge's corresponding acpi device (struct > > acpi_device) is not possible, for example: > > > > adev = ACPI_COMPANION(&host_bridge->dev); > > > > This could be useful to find a host bridge's fwnode handle and to > > determine and call additional host bridge ACPI parameters and methods > > such as HID/CID or _UID. > > When is this explicitly needed. "Could be useful" is interesting, but it > needs to have a practical need. It is needed and it is present on x86 AFAICS (see my last reply in this thread). This seems to be addressing an ARM64-specific issue. > > > > Make this work by linking the host bridge to its ACPI fw node. > > > > Signed-off-by: Robert Richter <rrichter@xxxxxxx> > > --- > > drivers/acpi/pci_root.c | 1 + > > 1 file changed, 1 insertion(+) > > > > diff --git a/drivers/acpi/pci_root.c b/drivers/acpi/pci_root.c > > index d57cf8454b93..846c979e4c29 100644 > > --- a/drivers/acpi/pci_root.c > > +++ b/drivers/acpi/pci_root.c > > @@ -1083,6 +1083,7 @@ struct pci_bus *acpi_pci_root_create(struct acpi_pci_root *root, > > goto out_release_info; > > > > host_bridge = to_pci_host_bridge(bus->bridge); > > + host_bridge->dev.fwnode = acpi_fwnode_handle(device); > > if (!(root->osc_control_set & OSC_PCI_EXPRESS_NATIVE_HP_CONTROL)) > > host_bridge->native_pcie_hotplug = 0; > > if (!(root->osc_control_set & OSC_PCI_SHPC_NATIVE_HP_CONTROL)) > > -- > > 2.30.2 > > > >
