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>

1 files changed, 8 insertions, 14 deletions

diff --git a/arch/x86/pci/legacy.c b/arch/x86/pci/legacy.c
index 4061bb0f267d..0daf264ddb6c 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();