xen: implement xen_hvm_register_pirq
xen_hvm_register_pirq allows the kernel to map a GSI into a Xen pirq and
receive the interrupt as an event channel from that point on.
Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
diff --git a/arch/x86/pci/xen.c b/arch/x86/pci/xen.c
index 4e37106..08e3cdc 100644
--- a/arch/x86/pci/xen.c
+++ b/arch/x86/pci/xen.c
@@ -17,6 +17,44 @@
#include <xen/events.h>
#include <asm/xen/pci.h>
+#ifdef CONFIG_ACPI
+static int xen_hvm_register_pirq(u32 gsi, int triggering)
+{
+ int rc, irq;
+ struct physdev_map_pirq map_irq;
+ int shareable = 0;
+ char *name;
+
+ if (!xen_hvm_domain())
+ return -1;
+
+ map_irq.domid = DOMID_SELF;
+ map_irq.type = MAP_PIRQ_TYPE_GSI;
+ map_irq.index = gsi;
+ map_irq.pirq = -1;
+
+ rc = HYPERVISOR_physdev_op(PHYSDEVOP_map_pirq, &map_irq);
+ if (rc) {
+ printk(KERN_WARNING "xen map irq failed %d\n", rc);
+ return -1;
+ }
+
+ if (triggering == ACPI_EDGE_SENSITIVE) {
+ shareable = 0;
+ name = "ioapic-edge";
+ } else {
+ shareable = 1;
+ name = "ioapic-level";
+ }
+
+ irq = xen_map_pirq_gsi(map_irq.pirq, gsi, shareable, name);
+
+ printk(KERN_DEBUG "xen: --> irq=%d, pirq=%d\n", irq, map_irq.pirq);
+
+ return irq;
+}
+#endif
+
#if defined(CONFIG_PCI_MSI)
#include <linux/msi.h>