From: Benjamin Herrenschmidt Date: Sat, 15 Jun 2019 10:23:56 +1000 Subject: [PATCH 3/4] arm64: PCI: Allow resource reallocation if necessary Origin: https://git.kernel.org/linus/3e8ba9686600e5f77e692126bf0293edf162989a Call pci_assign_unassigned_root_bus_resources() instead of the simpler: pci_bus_size_bridges(bus); pci_bus_assign_resources(bus); pci_assign_unassigned_root_bus_resources() calls: __pci_bus_size_bridges(bus, add_list); __pci_bus_assign_resources(bus, add_list, &fail_head); so this should be equivalent as long as we're able to assign everything. If we were unable to assign something, previously we did nothing and left it unassigned, but after this patch, we will attempt to do some reallocation. Once we start honoring FW resource allocations, this will bring up the "reallocation" feature which can help making room for SR-IOV when necessary. Link: https://lore.kernel.org/r/20190615002359.29577-1-benh@kernel.crashing.org Signed-off-by: Benjamin Herrenschmidt [bhelgaas: commit log] Signed-off-by: Bjorn Helgaas Acked-by: Lorenzo Pieralisi --- arch/arm64/kernel/pci.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) Index: linux/arch/arm64/kernel/pci.c =================================================================== --- linux.orig/arch/arm64/kernel/pci.c +++ linux/arch/arm64/kernel/pci.c @@ -194,8 +194,7 @@ struct pci_bus *pci_acpi_scan_root(struc if (!bus) return NULL; - pci_bus_size_bridges(bus); - pci_bus_assign_resources(bus); + pci_assign_unassigned_root_bus_resources(bus); list_for_each_entry(child, &bus->children, node) pcie_bus_configure_settings(child);