x86: Move pci init function to x86_init

The PCI initialization in pci_subsys_init() is a mess. pci_numaq_init,
pci_acpi_init, pci_visws_init and pci_legacy_init are called and each
implementation checks and eventually modifies the global variable
pcibios_scanned.

x86_init functions allow us to do this more elegant. The pci.init
function pointer is preset to pci_legacy_init. numaq, acpi and visws
can modify the pointer in their early setup functions. The functions
return 0 when they did the full initialization including bus scan. A
non zero return value indicates that pci_legacy_init needs to be
called either because the selected function failed or wants the
generic bus scan in pci_legacy_init to happen (e.g. visws).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
LKML-Reference: <43F901BD926A4E43B106BF17856F07559FB80CFE@orsmsx508.amr.corp.intel.com>
Acked-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Jacob Pan <jacob.jun.pan@intel.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>

5 files changed, 11 insertions, 35 deletions

diff --git a/arch/x86/pci/acpi.c b/arch/x86/pci/acpi.c
index 959e548..73b3fe9 100644
--- a/arch/x86/pci/acpi.c
+++ b/arch/x86/pci/acpi.c
@@ -282,15 +282,11 @@ int __init pci_acpi_init(void)
 {
 	struct pci_dev *dev = NULL;
 
-	if (pcibios_scanned)
-		return 0;
-
 	if (acpi_noirq)
-		return 0;
+		return -ENODEV;
 
 	printk(KERN_INFO "PCI: Using ACPI for IRQ routing\n");
 	acpi_irq_penalty_init();
-	pcibios_scanned++;
 	pcibios_enable_irq = acpi_pci_irq_enable;
 	pcibios_disable_irq = acpi_pci_irq_disable;
 
diff --git a/arch/x86/pci/common.c b/arch/x86/pci/common.c
index d2552c6..f5770b5 100644
--- a/arch/x86/pci/common.c
+++ b/arch/x86/pci/common.c
@@ -72,12 +72,6 @@ struct pci_ops pci_root_ops = {
 };
 
 /*
- * legacy, numa, and acpi all want to call pcibios_scan_root
- * from their initcalls. This flag prevents that.
- */
-int pcibios_scanned;
-
-/*
  * This interrupt-safe spinlock protects all accesses to PCI
  * configuration space.
  */
diff --git a/arch/x86/pci/legacy.c b/arch/x86/pci/legacy.c
index 4061bb0..0daf264 100644
--- a/arch/x86/pci/legacy.c
+++ b/arch/x86/pci/legacy.c
@@ -35,16 +35,13 @@ static void __devinit pcibios_fixup_peer_bridges(void)
 	}
 }
 
-static int __init pci_legacy_init(void)
+int __init pci_legacy_init(void)
 {
 	if (!raw_pci_ops) {
 		printk("PCI: System does not support PCI\n");
 		return 0;
 	}
 
-	if (pcibios_scanned++)
-		return 0;
-
 	printk("PCI: Probing PCI hardware\n");
 	pci_root_bus = pcibios_scan_root(0);
 	if (pci_root_bus)
@@ -55,16 +52,13 @@ static int __init pci_legacy_init(void)
 
 int __init pci_subsys_init(void)
 {
-#ifdef CONFIG_X86_NUMAQ
-	pci_numaq_init();
-#endif
-#ifdef CONFIG_ACPI
-	pci_acpi_init();
-#endif
-#ifdef CONFIG_X86_VISWS
-	pci_visws_init();
-#endif
-	pci_legacy_init();
+	/*
+	 * The init function returns an non zero value when
+	 * pci_legacy_init should be invoked.
+	 */
+	if (x86_init.pci.init())
+		pci_legacy_init();
+
 	pcibios_fixup_peer_bridges();
 	pcibios_irq_init();
 	pcibios_init();
diff --git a/arch/x86/pci/numaq_32.c b/arch/x86/pci/numaq_32.c
index 8eb295e..45c0c9e 100644
--- a/arch/x86/pci/numaq_32.c
+++ b/arch/x86/pci/numaq_32.c
@@ -152,14 +152,8 @@ int __init pci_numaq_init(void)
 {
 	int quad;
 
-	if (!found_numaq)
-		return 0;
-
 	raw_pci_ops = &pci_direct_conf1_mq;
 
-	if (pcibios_scanned++)
-		return 0;
-
 	pci_root_bus = pcibios_scan_root(0);
 	if (pci_root_bus)
 		pci_bus_add_devices(pci_root_bus);
diff --git a/arch/x86/pci/visws.c b/arch/x86/pci/visws.c
index bcead7a..03008f7 100644
--- a/arch/x86/pci/visws.c
+++ b/arch/x86/pci/visws.c
@@ -69,9 +69,6 @@ void __init pcibios_update_irq(struct pci_dev *dev, int irq)
 
 int __init pci_visws_init(void)
 {
-	if (!is_visws_box())
-		return -1;
-
 	pcibios_enable_irq = &pci_visws_enable_irq;
 	pcibios_disable_irq = &pci_visws_disable_irq;
 
@@ -90,5 +87,6 @@ int __init pci_visws_init(void)
 	pci_scan_bus_with_sysdata(pci_bus1);
 	pci_fixup_irqs(pci_common_swizzle, visws_map_irq);
 	pcibios_resource_survey();
-	return 0;
+	/* Request bus scan */
+	return 1;
 }