[PATCH kernel v4 3/6] PCI: Set PCI_BUS_FLAGS_MSI_REMAP if IOMMU have capability of IRQ remapping

[Alexey Kardashevskiy <aik@ozlabs.ru>]

From: Yongji Xie <elohimes@gmail.com>

The capability of IRQ remapping is abstracted on IOMMU side on
some archs. There is a existing flag IOMMU_CAP_INTR_REMAP for this.

To have a universal flag to test this capability for different
archs on PCI side, we set PCI_BUS_FLAGS_MSI_REMAP for PCI buses
when IOMMU_CAP_INTR_REMAP is set.

Signed-off-by: Yongji Xie <xyjxie@linux.vnet.ibm.com>
Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
---
 drivers/pci/probe.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c
index 3529ae17b70e..f2393b7d7ebf 100644
--- a/drivers/pci/probe.c
+++ b/drivers/pci/probe.c
@@ -775,6 +775,9 @@ int pci_register_host_bridge(struct pci_host_bridge *bridge)
 	pci_set_bus_of_node(bus);
 	pci_set_bus_msi_domain(bus);
 
+	if (iommu_capable(&pci_bus_type, IOMMU_CAP_INTR_REMAP))
+		b->bus_flags |= PCI_BUS_FLAGS_MSI_REMAP;
+
 	if (!parent)
 		set_dev_node(bus->bridge, pcibus_to_node(bus));
 
-- 
2.11.0