[PATCH 01/10] PCI: save pci_bus pointer in pcie_port structure

Vidya Sagar
2019-03-26T15:14:23Z

save pci_bus pointer created by PCIe sub-system's
pci_scan_root_bus_bridge() to be used by host controller drivers for post
processing. Tegra host controller driver needs it for the following
reasons
- to derive pci_host_bridge structure from pci_bus which is used to
configure iATU's outbound regions for different windows accesses
- to traverse and configure downstream hierarchy. One such case is,
configuring all immediate downstream devices to D0 state before transiting
link to L2 state. Saving pci_bus pointer seems the best method compared to
deriving it by other means.

Signed-off-by: Vidya Sagar <vidyas@nvidia.com>
---
drivers/pci/controller/dwc/pcie-designware-host.c | 1 +
drivers/pci/controller/dwc/pcie-designware.h | 1 +
2 files changed, 2 insertions(+)

diff --git a/drivers/pci/controller/dwc/pcie-designware-host.c b/drivers/pci/controller/dwc/pcie-designware-host.c
index 25087d3c9a82..15add3cf3945 100644
--- a/drivers/pci/controller/dwc/pcie-designware-host.c
+++ b/drivers/pci/controller/dwc/pcie-designware-host.c
@@ -494,6 +494,7 @@ int dw_pcie_host_init(struct pcie_port *pp)
goto error;

bus = bridge->bus;
+ pp->bus = bus;

if (pp->ops->scan_bus)
pp->ops->scan_bus(pp);
diff --git a/drivers/pci/controller/dwc/pcie-designware.h b/drivers/pci/controller/dwc/pcie-designware.h
index 377f4c0b52da..70007276bc93 100644
--- a/drivers/pci/controller/dwc/pcie-designware.h
+++ b/drivers/pci/controller/dwc/pcie-designware.h
@@ -175,6 +175,7 @@ struct pcie_port {
struct resource *busn;
int irq;
const struct dw_pcie_host_ops *ops;
+ struct pci_bus *bus;
int msi_irq;
struct irq_domain *irq_domain;
struct irq_domain *msi_domain;
--
2.7.4