On Monday 19 January 2015 11:17:02 Yijing Wang wrote: > On 2015/1/16 18:01, Arnd Bergmann wrote: > > On Friday 16 January 2015 09:44:16 Yijing Wang wrote: > >> +static void pci_host_bridge_probe_mode( > >> + struct pci_host_bridge *host) > >> +{ > >> + host->of_scan = true; > >> +} > >> > > > > I probably missed something here, but where does host->of_scan > > get used? > > > > It is used in __pci_scan_root_bus() to detect whether of scan bus is needed > in patch 11.
Ok, I see it now. > @@ -2051,10 +2053,17 @@ static struct pci_bus *__pci_scan_root_bus( > pci_bus_insert_busn_res(b, host->busnum, 255); > } > > - max = pci_scan_child_bus(b); > + if (host->ops && host->ops->phb_probe_mode) > + host->ops->phb_probe_mode(host); > > - if (!found) > - pci_bus_update_busn_res_end(b, max); > + if (host->of_scan) { > + if (host->ops &&host->ops->phb_of_scan_bus) > + host->ops->phb_of_scan_bus(host); > + } else { > + max = pci_scan_child_bus(b); > + if (!found) > + pci_bus_update_busn_res_end(b, max); > + } > I think we can simplify this based on the knowledge that this code will remain powerpc specific. How about removing the phb_probe_mode() callback and replacing it with just a phb_scan_bus() callback that will always get set on sparc, and do this on powerpc: +static void pci_host_bridge_of_scan_bus(struct pci_host_bridge *host) +{ + int mode = PCI_PROBE_NORMAL; + struct pci_bus *bus = host->bus; + struct pci_controller *hose = dev_get_drvdata(&host->dev); + + /* Get probe mode and perform scan */ + if (hose->dn && ppc_md.pci_probe_mode) + mode = ppc_md.pci_probe_mode(bus); + + pr_debug(" probe mode: %d\n", mode); + if (mode == PCI_PROBE_DEVTREE) { + of_scan_bus(host->dn, bus); + return max; // XXX need to get this from somewhere + } + return pci_scan_child_bus(b); +} Would that work? Arnd -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/