x86/pci: insert ioapic resource before assigning unassigned resources

Stephen reported that his DL585 G2 needed noapic after 2.6.22 (?)

Dann bisected it down to:
  commit 30a18d6
  Date:   Tue Feb 19 03:21:20 2008 -0800

      x86: multi pci root bus with different io resource range, on
      64-bit

It turns out that:
  1. that AMD-based systems have two HT chains.
  2. BIOS doesn't allocate resources for BAR 6 of devices under 8132 etc
  3. that multi-peer-root patch will try to split root resources to peer
     root resources according to PCI conf of NB
  4. PCI core assigns unassigned resources, but they overlap with BARs
     that are used by ioapic addr of io4 and 8132.

The reason: at that point ioapic address are not inserted yet.  Solution
is to insert ioapic resources into the tree a bit earlier.

Reported-by: Stephen Frost <sfrost@snowman.net>
Reported-and-Tested-by: dann frazier <dannf@hp.com>
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Cc: stable@kernel.org
Signed-off-by: Jesse Barnes <jbarnes@jbarnes-g45.(none)>

arch/x86/include/asm/io_apic.h

@@ -161,6 +161,7 @@ extern int io_apic_set_pci_routing(struct device *dev, int irq,
 		 struct io_apic_irq_attr *irq_attr);
 extern int (*ioapic_renumber_irq)(int ioapic, int irq);
 extern void ioapic_init_mappings(void);
+extern void ioapic_insert_resources(void);
 
 extern struct IO_APIC_route_entry **alloc_ioapic_entries(void);
 extern void free_ioapic_entries(struct IO_APIC_route_entry **ioapic_entries);
@@ -180,6 +181,7 @@ extern void ioapic_write_entry(int apic, int pin,
 #define io_apic_assign_pci_irqs 0
 static const int timer_through_8259 = 0;
 static inline void ioapic_init_mappings(void)	{ }
+static inline void ioapic_insert_resources(void) { }
 
 static inline void probe_nr_irqs_gsi(void)	{ }
 #endif

arch/x86/kernel/apic/io_apic.c

@@ -4181,28 +4181,20 @@ void __init ioapic_init_mappings(void)
 	}
 }
 
-static int __init ioapic_insert_resources(void)
+void __init ioapic_insert_resources(void)
 {
 	int i;
 	struct resource *r = ioapic_resources;
 
 	if (!r) {
-		if (nr_ioapics > 0) {
+		if (nr_ioapics > 0)
 			printk(KERN_ERR
 				"IO APIC resources couldn't be allocated.\n");
-			return -1;
-		}
-		return 0;
+		return;
 	}
 
 	for (i = 0; i < nr_ioapics; i++) {
 		insert_resource(&iomem_resource, r);
 		r++;
 	}
-
-	return 0;
 }
-
-/* Insert the IO APIC resources after PCI initialization has occured to handle
- * IO APICS that are mapped in on a BAR in PCI space. */
-late_initcall(ioapic_insert_resources);

arch/x86/pci/i386.c

@@ -35,6 +35,7 @@
 #include <asm/pat.h>
 #include <asm/e820.h>
 #include <asm/pci_x86.h>
+#include <asm/io_apic.h>
 
 
 static int
@@ -227,6 +228,12 @@ void __init pcibios_resource_survey(void)
 	pcibios_allocate_resources(1);
 
 	e820_reserve_resources_late();
+	/*
+	 * Insert the IO APIC resources after PCI initialization has
+	 * occured to handle IO APICS that are mapped in on a BAR in
+	 * PCI space, but before trying to assign unassigned pci res.
+	 */
+	ioapic_insert_resources();
 }
 
 /**