powerpc/powernv: Reset root port in firmware

commit 372cf12 upstream.

Resetting root port has more stuff to do than that for PCIe switch
ports and we should have resetting root port done in firmware instead
of the kernel itself. The problem was introduced by commit 5b2e198
("powerpc/powernv: Rework EEH reset").

Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

arch/powerpc/platforms/powernv/eeh-ioda.c

@@ -549,7 +549,8 @@ static int ioda_eeh_reset(struct eeh_pe *pe, int option)
 		ret = ioda_eeh_phb_reset(hose, option);
 	} else {
 		bus = eeh_pe_bus_get(pe);
-		if (pci_is_root_bus(bus))
+		if (pci_is_root_bus(bus) ||
+		    pci_is_root_bus(bus->parent))
 			ret = ioda_eeh_root_reset(hose, option);
 		else
 			ret = ioda_eeh_bridge_reset(hose, bus->self, option);