iommu/vt-d: Implement select() method on remapping irqdomain

Preparatory for removing irq_remapping_get_irq_domain()
Signed-off-by: NDavid Woodhouse <dwmw@amazon.co.uk>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/20201024213535.443185-26-dwmw2@infradead.org

drivers/iommu/intel/irq_remapping.c

@@ -1431,7 +1431,20 @@ static void intel_irq_remapping_deactivate(struct irq_domain *domain,
 	modify_irte(&data->irq_2_iommu, &entry);
 }
 
+static int intel_irq_remapping_select(struct irq_domain *d,
+				      struct irq_fwspec *fwspec,
+				      enum irq_domain_bus_token bus_token)
+{
+	if (x86_fwspec_is_ioapic(fwspec))
+		return d == map_ioapic_to_ir(fwspec->param[0]);
+	else if (x86_fwspec_is_hpet(fwspec))
+		return d == map_hpet_to_ir(fwspec->param[0]);
+
+	return 0;
+}
+
 static const struct irq_domain_ops intel_ir_domain_ops = {
+	.select = intel_irq_remapping_select,
 	.alloc = intel_irq_remapping_alloc,
 	.free = intel_irq_remapping_free,
 	.activate = intel_irq_remapping_activate,