Re: [PATCH 1/1 v2 ] PCI: Mobiveil: Add Mobiveil PCIe Host Bridge IP driver

[Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>]

On Tue, Nov 21, 2017 at 08:40:24AM -0600, Bjorn Helgaas wrote:
> [+cc Lorenzo, Tanmay]
> 
> On Tue, Nov 21, 2017 at 05:45:16PM +0530, Subrahmanya Lingappa wrote:
> > On Fri, Nov 10, 2017 at 5:13 AM, Bjorn Helgaas <helgaas@kernel.org> wrote:
> > > On Thu, Nov 09, 2017 at 05:33:03PM +0530, subrahmanya_lingappa wrote:
> 
> > >> +     /* create the PCIe root bus */
> > >> +     bus =
> > >> +         pci_create_root_bus(&pdev->dev, 0, &mobiveil_pcie_ops, pcie, &res);
> > >> +     if (!bus)
> > >> +             return -ENOMEM;
> > >> +
> > >> +     /* setup MSI, if enabled */
> > >> +     if (IS_ENABLED(CONFIG_PCI_MSI)) {
> > >> +             mobiveil_pcie_msi_chip.dev = &pcie->pdev->dev;
> > >> +             bus->msi = &mobiveil_pcie_msi_chip;
> > >> +     }
> > >> +
> > >> +     /* setup the kernel resources for the newly added PCIe root bus */
> > >> +     pci_scan_child_bus(bus);
> > >
> > > Use pci_scan_root_bus_bridge().  For example, see
> > > http://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=123db533072e
> > >
> > >> +     pci_assign_unassigned_bus_resources(bus);
> > >> +
> > >> +     list_for_each_entry(child, &bus->children, node)
> > >> +             pcie_bus_configure_settings(child);
> > >> +
> > >> +     pci_fixup_irqs(pci_common_swizzle, of_irq_parse_and_map_pci);
> > >
> > > pci_scan_root_bus_bridge() also takes care of this pci_fixup_irqs()
> > > (which doesn't exist anymore); see
> > > http://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=6ab380957838
> > >
> > I am testing this driver on a board whcih supports  Xilinx's latest
> > Petalinux build environment has Linux-4.9 kernel version with all
> > the patches from Xilinx included in it. But these
> > pci_scan_root_bus_bridge() and friends we added in recent versions
> > will it be ok keeping pci_scan_child_bus() for now ?
> 
> I would strongly prefer to use pci_scan_root_bus_bridge().  As I
> mentioned, pci_fixup_irqs() doesn't even exist upstream anymore, so
> this can't be merged as-is.
> 
> BTW, Lorenzo, it looks like 9af275be15f7 ("PCI: xgene: Convert PCI
> scan API to pci_scan_root_bus_bridge()") forgot to remove the
> pci_scan_child_bus() call from xgene_pcie_probe().

I will remove it straight away - apologies.

Thanks,
Lorenzo