xen/pci: Squash pci_xen_initial_domain and xen_setup_pirqs together.

Since they are only called once and the rest of the pci_xen_*
functions follow the same pattern of setup.
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>

arch/x86/include/asm/xen/pci.h

@@ -14,13 +14,14 @@ static inline int pci_xen_hvm_init(void)
 }
 #endif
 #if defined(CONFIG_XEN_DOM0)
-void __init xen_setup_pirqs(void);
+int __init pci_xen_initial_domain(void);
 int xen_find_device_domain_owner(struct pci_dev *dev);
 int xen_register_device_domain_owner(struct pci_dev *dev, uint16_t domain);
 int xen_unregister_device_domain_owner(struct pci_dev *dev);
 #else
-static inline void __init xen_setup_pirqs(void)
+static inline int __init pci_xen_initial_domain(void)
 {
+	return -1;
 }
 static inline int xen_find_device_domain_owner(struct pci_dev *dev)
 {

arch/x86/pci/xen.c

@@ -429,8 +429,11 @@ static __init void xen_setup_acpi_sci(void)
 	return;
 }
 #endif
-static int __init pci_xen_initial_domain(void)
+
+int __init pci_xen_initial_domain(void)
 {
+	int pirq, irq;
+
 #ifdef CONFIG_PCI_MSI
 	x86_msi.setup_msi_irqs = xen_initdom_setup_msi_irqs;
 	x86_msi.teardown_msi_irq = xen_teardown_msi_irq;
@@ -439,15 +442,6 @@ static int __init pci_xen_initial_domain(void)
 	xen_setup_acpi_sci();
 	__acpi_register_gsi = acpi_register_gsi_xen;
 #endif
-	return 0;
-}
-
-void __init xen_setup_pirqs(void)
-{
-	int pirq, irq;
-
-	pci_xen_initial_domain();
-
 	if (0 == nr_ioapics) {
 		for (irq = 0; irq < NR_IRQS_LEGACY; irq++) {
 			pirq = xen_allocate_pirq_gsi(irq);
@@ -456,7 +450,7 @@ void __init xen_setup_pirqs(void)
 				break;
 			irq = xen_bind_pirq_gsi_to_irq(irq, pirq, 0, "xt-pic");
 		}
-		return;
+		return 0;
 	}
 #ifdef CONFIG_ACPI
 	/* Pre-allocate legacy irqs */
@@ -471,6 +465,7 @@ void __init xen_setup_pirqs(void)
 			true /* allocate IRQ */);
 	}
 #endif
+	return 0;
 }
 
 struct xen_device_domain_owner {

drivers/xen/events.c

@@ -1693,6 +1693,6 @@ void __init xen_init_IRQ(void)
 	} else {
 		irq_ctx_init(smp_processor_id());
 		if (xen_initial_domain())
-			xen_setup_pirqs();
+			pci_xen_initial_domain();
 	}
 }