On Tue, Jul 23, 2019 at 12:27:11PM +0300, Jonathan Chocron wrote:
> This basically aligns the usage of PCI_PROBE_ONLY and
> PCI_REASSIGN_ALL_BUS in dw_pcie_host_init() with the logic in
> pci_host_common_probe().
>
> Now it will be possible to control via the devicetree whether to just
> probe the PCI bus (in cases where FW already configured it) or to fully
> configure it.
>
> Signed-off-by: Jonathan Chocron <jon...@amazon.com>
> ---
> .../pci/controller/dwc/pcie-designware-host.c | 23 +++++++++++++++----
> 1 file changed, 19 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/pci/controller/dwc/pcie-designware-host.c
> b/drivers/pci/controller/dwc/pcie-designware-host.c
> index d2ca748e4c85..0a294d8aa21a 100644
> --- a/drivers/pci/controller/dwc/pcie-designware-host.c
> +++ b/drivers/pci/controller/dwc/pcie-designware-host.c
> @@ -342,6 +342,8 @@ int dw_pcie_host_init(struct pcie_port *pp)
> if (!bridge)
> return -ENOMEM;
>
> + of_pci_check_probe_only();
> +
> ret = devm_of_pci_get_host_bridge_resources(dev, 0, 0xff,
> &bridge->windows, &pp->io_base);
> if (ret)
> @@ -474,6 +476,10 @@ int dw_pcie_host_init(struct pcie_port *pp)
>
> pp->root_bus_nr = pp->busn->start;
>
> + /* Do not reassign bus nums if probe only */
> + if (!pci_has_flag(PCI_PROBE_ONLY))
> + pci_add_flags(PCI_REASSIGN_ALL_BUS);
This changes the default for bus reassignment on all DWC host (that are
!PCI_PROBE_ONLY), we should drop this line, it can trigger regressions.
If we still want to merge it as a separate change we must test it on all
DWC host bridges to make sure it does not trigger any issues with
current set-ups, that's not going to be easy though.
Lorenzo
> +
> bridge->dev.parent = dev;
> bridge->sysdata = pp;
> bridge->busnr = pp->root_bus_nr;
> @@ -490,11 +496,20 @@ int dw_pcie_host_init(struct pcie_port *pp)
> if (pp->ops->scan_bus)
> pp->ops->scan_bus(pp);
>
> - pci_bus_size_bridges(pp->root_bus);
> - pci_bus_assign_resources(pp->root_bus);
> + /*
> + * We insert PCI resources into the iomem_resource and
> + * ioport_resource trees in either pci_bus_claim_resources()
> + * or pci_bus_assign_resources().
> + */
> + if (pci_has_flag(PCI_PROBE_ONLY)) {
> + pci_bus_claim_resources(pp->root_bus);
> + } else {
> + pci_bus_size_bridges(pp->root_bus);
> + pci_bus_assign_resources(pp->root_bus);
>
> - list_for_each_entry(child, &pp->root_bus->children, node)
> - pcie_bus_configure_settings(child);
> + list_for_each_entry(child, &pp->root_bus->children, node)
> + pcie_bus_configure_settings(child);
> + }
>
> pci_bus_add_devices(pp->root_bus);
> return 0;
> --
> 2.17.1
>
