@@ -925,6 +925,8 @@ static int pci_register_host_bridge(struct pci_host_bridge *bridge)
device_enable_async_suspend(bus->bridge);
pci_set_bus_of_node(bus);
pci_set_bus_msi_domain(bus);
+ if (bridge->msi_domain && !dev_get_msi_domain(&bus->dev))
+ bus->bus_flags |= PCI_BUS_FLAGS_NO_MSI;
if (!parent)
set_dev_node(bus->bridge, pcibus_to_node(bus));
@@ -550,6 +550,7 @@ struct pci_host_bridge {
unsigned int native_dpc:1; /* OS may use PCIe DPC */
unsigned int preserve_config:1; /* Preserve FW resource setup */
unsigned int size_windows:1; /* Enable root bus sizing */
+ unsigned int msi_domain:1; /* Bridge wants MSI domain */
/* Resource alignment requirements */
resource_size_t (*align_resource)(struct pci_dev *dev,
There is a whole class of host bridges that cannot know whether MSIs will be provided or not, as they rely on other blocks to provide the MSI functionnality, using MSI domains. This is the case for example on systems that use the ARM GIC architecture. Introduce a new attribute ('msi_domain') indicating that implicit dependency, and use this property to set the NO_MSI flag when no MSI domain is found at probe time. Acked-by: Bjorn Helgaas <bhelgaas@google.com> Signed-off-by: Marc Zyngier <maz@kernel.org> --- drivers/pci/probe.c | 2 ++ include/linux/pci.h | 1 + 2 files changed, 3 insertions(+)