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>

15 files changed, 53 insertions, 46 deletions

diff --git a/arch/x86/include/asm/numaq.h b/arch/x86/include/asm/numaq.h
index 9f0a5f5d29ec..ef6bf81f8460 100644
--- a/arch/x86/include/asm/numaq.h
+++ b/arch/x86/include/asm/numaq.h
@@ -30,6 +30,7 @@
 
 extern int found_numaq;
 extern int get_memcfg_numaq(void);
+extern int pci_numaq_init(void);
 
 extern void *xquad_portio;
 
diff --git a/arch/x86/include/asm/pci.h b/arch/x86/include/asm/pci.h
index ada8c201d513..8bd433ccc242 100644
--- a/arch/x86/include/asm/pci.h
+++ b/arch/x86/include/asm/pci.h
@@ -45,8 +45,15 @@ static inline int pci_proc_domain(struct pci_bus *bus)
 
 #ifdef CONFIG_PCI
 extern unsigned int pcibios_assign_all_busses(void);
+extern int pci_legacy_init(void);
+# ifdef CONFIG_ACPI
+#  define x86_default_pci_init pci_acpi_init
+# else
+#  define x86_default_pci_init pci_legacy_init
+# endif
 #else
-#define pcibios_assign_all_busses()     0
+# define pcibios_assign_all_busses()    0
+# define x86_default_pci_init           NULL
 #endif
 
 extern unsigned long pci_mem_start;
diff --git a/arch/x86/include/asm/pci_x86.h b/arch/x86/include/asm/pci_x86.h
index b4bf9a942ed0..440124f1224d 100644
--- a/arch/x86/include/asm/pci_x86.h
+++ b/arch/x86/include/asm/pci_x86.h
@@ -82,7 +82,6 @@ struct irq_routing_table {
 
 extern unsigned int pcibios_irq_mask;
 
-extern int pcibios_scanned;
 extern spinlock_t pci_config_lock;
 
 extern int (*pcibios_enable_irq)(struct pci_dev *dev);
@@ -112,9 +111,8 @@ extern void __init dmi_check_skip_isa_align(void);
 /* some common used subsys_initcalls */
 extern int __init pci_acpi_init(void);
 extern int __init pcibios_irq_init(void);
-extern int __init pci_visws_init(void);
-extern int __init pci_numaq_init(void);
 extern int __init pcibios_init(void);
+extern int pci_legacy_init(void);
 
 /* pci-mmconfig.c */
 
@@ -182,3 +180,13 @@ static inline void mmio_config_writel(void __iomem *pos, u32 val)
 {
         asm volatile("movl %%eax,(%1)" : : "a" (val), "r" (pos) : "memory");
 }
+
+#ifdef CONFIG_PCI
+# ifdef CONFIG_ACPI
+#  define x86_default_pci_init          pci_acpi_init
+# else
+#  define x86_default_pci_init          pci_legacy_init
+# endif
+#else
+# define x86_default_pci_init           NULL
+#endif
diff --git a/arch/x86/include/asm/setup.h b/arch/x86/include/asm/setup.h
index 18e496c98ff0..86b1506f4179 100644
--- a/arch/x86/include/asm/setup.h
+++ b/arch/x86/include/asm/setup.h
@@ -37,10 +37,8 @@ void setup_bios_corruption_check(void);
 
 #ifdef CONFIG_X86_VISWS
 extern void visws_early_detect(void);
-extern int is_visws_box(void);
 #else
 static inline void visws_early_detect(void) { }
-static inline int is_visws_box(void) { return 0; }
 #endif
 
 extern unsigned long saved_video_mode;
diff --git a/arch/x86/include/asm/visws/cobalt.h b/arch/x86/include/asm/visws/cobalt.h
index 166adf61e770..2edb37637ead 100644
--- a/arch/x86/include/asm/visws/cobalt.h
+++ b/arch/x86/include/asm/visws/cobalt.h
@@ -122,4 +122,6 @@ extern char visws_board_type;
 
 extern char visws_board_rev;
 
+extern int pci_visws_init(void);
+
 #endif /* _ASM_X86_VISWS_COBALT_H */
diff --git a/arch/x86/include/asm/x86_init.h b/arch/x86/include/asm/x86_init.h
index ea0e8ea15e15..f145d843f03d 100644
--- a/arch/x86/include/asm/x86_init.h
+++ b/arch/x86/include/asm/x86_init.h
@@ -98,6 +98,14 @@ struct x86_init_iommu {
         int (*iommu_init)(void);
 };
 
+ /*
+  * struct x86_init_pci - platform specific pci init functions
+ * @init:                       platform specific pci init
+ */
+struct x86_init_pci {
+        int (*init)(void);
+};
+
 /**
  * struct x86_init_ops - functions for platform specific setup
  *
@@ -110,6 +118,7 @@ struct x86_init_ops {
         struct x86_init_paging          paging;
         struct x86_init_timers          timers;
         struct x86_init_iommu           iommu;
+        struct x86_init_pci             pci;
 };
 
 /**
diff --git a/arch/x86/kernel/acpi/boot.c b/arch/x86/kernel/acpi/boot.c
index 0acbcdfa5ca4..054a5f5548b0 100644
--- a/arch/x86/kernel/acpi/boot.c
+++ b/arch/x86/kernel/acpi/boot.c
@@ -35,6 +35,7 @@
 #include <linux/ioport.h>
 #include <linux/pci.h>
 
+#include <asm/pci_x86.h>
 #include <asm/pgtable.h>
 #include <asm/io_apic.h>
 #include <asm/apic.h>
@@ -1604,6 +1605,9 @@ int __init acpi_boot_init(void)
 
         acpi_table_parse(ACPI_SIG_HPET, acpi_parse_hpet);
 
+        if (!acpi_noirq)
+                x86_init.pci.init = pci_acpi_init;
+
         return 0;
 }
 
diff --git a/arch/x86/kernel/apic/numaq_32.c b/arch/x86/kernel/apic/numaq_32.c
index 98c4665f251c..be5c4fd47778 100644
--- a/arch/x86/kernel/apic/numaq_32.c
+++ b/arch/x86/kernel/apic/numaq_32.c
@@ -277,6 +277,7 @@ static __init void early_check_numaq(void)
                 x86_init.mpparse.mpc_oem_pci_bus = mpc_oem_pci_bus;
                 x86_init.mpparse.mpc_oem_bus_info = mpc_oem_bus_info;
                 x86_init.timers.tsc_pre_init = numaq_tsc_init;
+                x86_init.pci.init = pci_numaq_init;
         }
 }
 
diff --git a/arch/x86/kernel/visws_quirks.c b/arch/x86/kernel/visws_quirks.c
index 34a279a7471d..843e9d30a1e3 100644
--- a/arch/x86/kernel/visws_quirks.c
+++ b/arch/x86/kernel/visws_quirks.c
@@ -49,11 +49,6 @@ extern int no_broadcast;
 char visws_board_type   = -1;
 char visws_board_rev    = -1;
 
-int is_visws_box(void)
-{
-        return visws_board_type >= 0;
-}
-
 static void __init visws_time_init(void)
 {
         printk(KERN_INFO "Starting Cobalt Timer system clock\n");
@@ -242,6 +237,7 @@ void __init visws_early_detect(void)
         x86_init.irqs.pre_vector_init = visws_pre_intr_init;
         x86_init.irqs.trap_init = visws_trap_init;
         x86_init.timers.timer_init = visws_time_init;
+        x86_init.pci.init = pci_visws_init;
 
         /*
          * Install reboot quirks:
diff --git a/arch/x86/kernel/x86_init.c b/arch/x86/kernel/x86_init.c
index ccd179dec36e..81faa6d67d69 100644
--- a/arch/x86/kernel/x86_init.c
+++ b/arch/x86/kernel/x86_init.c
@@ -7,6 +7,7 @@
 
 #include <asm/bios_ebda.h>
 #include <asm/paravirt.h>
+#include <asm/pci_x86.h>
 #include <asm/mpspec.h>
 #include <asm/setup.h>
 #include <asm/apic.h>
@@ -70,6 +71,10 @@ struct x86_init_ops x86_init __initdata = {
         .iommu = {
                 .iommu_init             = iommu_init_noop,
         },
+
+        .pci = {
+                .init                   = x86_default_pci_init,
+        },
 };
 
 struct x86_cpuinit_ops x86_cpuinit __cpuinitdata = {
diff --git a/arch/x86/pci/acpi.c b/arch/x86/pci/acpi.c
index 959e548a7039..73b3fe9aa716 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 d2552c68e94d..f5770b5846a6 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 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();
diff --git a/arch/x86/pci/numaq_32.c b/arch/x86/pci/numaq_32.c
index 8eb295e116f6..45c0c9e45903 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 bcead7a46871..03008f72eb04 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;
 }