powerpc/pci: Update bridge windows on PCI plug

On the PCI plugging event, PCI slot's subordinate devices are
scanned and their (IO and MMIO) resources are assigned. Platform
dependent resources (PE#, IO/MMIO/DMA windows) are allocated or
created on updating windows of the slot's upstream bridge.

This updates the windows of the hot plugged slot's upstream bridge
in pcibios_finish_adding_to_bus() so that the platform resources
(PE#, IO/MMIO/DMA segments) are allocated or created accordingly.

Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Reviewed-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

arch/powerpc/kernel/pci-common.c

@@ -1444,8 +1444,12 @@ void pcibios_finish_adding_to_bus(struct pci_bus *bus)
 	/* Allocate bus and devices resources */
 	pcibios_allocate_bus_resources(bus);
 	pcibios_claim_one_bus(bus);
-	if (!pci_has_flag(PCI_PROBE_ONLY))
-		pci_assign_unassigned_bus_resources(bus);
+	if (!pci_has_flag(PCI_PROBE_ONLY)) {
+		if (bus->self)
+			pci_assign_unassigned_bridge_resources(bus->self);
+		else
+			pci_assign_unassigned_bus_resources(bus);
+	}
 
 	/* Fixup EEH */
 	eeh_add_device_tree_late(bus);