From 94e89b145371b68fa0ea294855adebcd03e0522e Mon Sep 17 00:00:00 2001 From: Marc Zyngier Date: Tue, 30 Mar 2021 16:11:41 +0100 Subject: PCI/MSI: Let PCI host bridges declare their reliance on MSI domains 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. Link: https://lore.kernel.org/r/20210330151145.997953-11-maz@kernel.org Signed-off-by: Marc Zyngier Signed-off-by: Lorenzo Pieralisi Acked-by: Bjorn Helgaas --- drivers/pci/probe.c | 2 ++ 1 file changed, 2 insertions(+) (limited to 'drivers/pci') diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c index fb04fc81a8bd..aa6fba35f5d1 100644 --- a/drivers/pci/probe.c +++ b/drivers/pci/probe.c @@ -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)); -- cgit v1.2.3