@@ -286,6 +286,7 @@ void __pci_bus_assign_resources(const struct pci_bus *bus,
struct list_head *realloc_head,
struct list_head *fail_head);
bool pci_bus_clip_resource(struct pci_dev *dev, int idx);
+void pci_bus_release_root_bridge_resources(struct pci_bus *bus);
void pci_reassigndev_resource_alignment(struct pci_dev *dev);
void pci_disable_bridge_window(struct pci_dev *dev);
@@ -3250,6 +3250,25 @@ static void pci_bus_rescan_done(struct pci_bus *bus)
}
}
+static void pci_setup_bridges(struct pci_bus *bus)
+{
+ struct pci_dev *dev;
+
+ list_for_each_entry(dev, &bus->devices, bus_list) {
+ struct pci_bus *child;
+
+ if (!pci_dev_is_added(dev))
+ continue;
+
+ child = dev->subordinate;
+ if (child)
+ pci_setup_bridges(child);
+ }
+
+ if (bus->self)
+ pci_setup_bridge(bus);
+}
+
/**
* pci_rescan_bus - Scan a PCI bus for devices
* @bus: PCI bus to scan
@@ -3271,8 +3290,11 @@ unsigned int pci_rescan_bus(struct pci_bus *bus)
pci_bus_rescan_prepare(root);
max = pci_scan_child_bus(root);
+
+ pci_bus_release_root_bridge_resources(root);
pci_assign_unassigned_root_bus_resources(root);
+ pci_setup_bridges(root);
pci_bus_rescan_done(root);
} else {
max = pci_scan_child_bus(bus);
@@ -1663,6 +1663,15 @@ static void pci_bus_release_bridge_resources(struct pci_bus *bus,
pci_bridge_release_resources(bus, type);
}
+void pci_bus_release_root_bridge_resources(struct pci_bus *root_bus)
+{
+ pci_bus_release_bridge_resources(root_bus, IORESOURCE_IO, whole_subtree);
+ pci_bus_release_bridge_resources(root_bus, IORESOURCE_MEM, whole_subtree);
+ pci_bus_release_bridge_resources(root_bus,
+ IORESOURCE_MEM_64 | IORESOURCE_PREFETCH,
+ whole_subtree);
+}
+
static void pci_bus_dump_res(struct pci_bus *bus)
{
struct resource *res;
When the movable BARs feature is enabled and a rescan has been requested, release all bridge windows and recalculate them from scratch, taking into account all kinds of BARs: fixed, movable, new. Comparing to simply trying to expand bridge windows, this also employs the PCI ability to shuffle BARs within a bridge, increasing the chances to find a memory space to fit BARs of newly hot-added devices, especially if no (or not enough) gaps were reserved by the BIOS/bootloader/firmware. The last step of writing the recalculated windows to the bridges is done by the new pci_setup_bridges() function. Signed-off-by: Sergei Miroshnichenko <s.miroshnichenko@yadro.com> --- drivers/pci/pci.h | 1 + drivers/pci/probe.c | 22 ++++++++++++++++++++++ drivers/pci/setup-bus.c | 9 +++++++++ 3 files changed, 32 insertions(+)