When _DSM #5 returns 0 for a host bridge, we need to claim the existing resources rather than reassign everything. Signed-off-by: Benjamin Herrenschmidt <benh@xxxxxxxxxxxxxxxxxxx> --- arch/arm64/kernel/pci.c | 11 +++++++++++ 1 file changed, 11 insertions(+) diff --git a/arch/arm64/kernel/pci.c b/arch/arm64/kernel/pci.c index 1419b1b4e9b9..a2c608a3fc41 100644 --- a/arch/arm64/kernel/pci.c +++ b/arch/arm64/kernel/pci.c @@ -168,6 +168,7 @@ struct pci_bus *pci_acpi_scan_root(struct acpi_pci_root *root) struct acpi_pci_generic_root_info *ri; struct pci_bus *bus, *child; struct acpi_pci_root_ops *root_ops; + struct pci_host_bridge *hb; ri = kzalloc(sizeof(*ri), GFP_KERNEL); if (!ri) @@ -193,6 +194,16 @@ struct pci_bus *pci_acpi_scan_root(struct acpi_pci_root *root) if (!bus) return NULL; + hb = pci_find_host_bridge(bus); + + /* If ACPI tells us to preserve the resource configuration, claim now */ + if (hb->preserve_config) + pci_bus_claim_resources(bus); + + /* + * Assign whatever was left unassigned. If we didn't claim above, this will + * reassign everything. + */ pci_assign_unassigned_root_bus_resources(bus); list_for_each_entry(child, &bus->children, node) -- 2.17.1
