[PATCH} x86/pci: insert ioapic resource before assign unassigned resource for pci

[Yinghai Lu <yinghai@kernel.org>]

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

Bann bisected
  --------------------------------------------------------------------
  commit 30a18d6c3f1e774de656ebd8ff219d53e2ba4029
  Date:   Tue Feb 19 03:21:20 2008 -0800

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

it turns out that
1. that system have two HT chains.
2. BIOS doesn't allocate resource for BAR 6 under 8132 etc
3. that patches will try to split root resource to peer root resources
   according to pci conf of NB
4. pci assign unassign path, assign some range to pci-x  bridge, but it
   is overlapping with ioapic addr of io4 and 8132.

the reason is at that point ioapic address and BAR is not inserted yet.
the BAR for io4 ioapic is not in regular position.
the BAR for 8132 is sitting to func1, and pci-x bridge is func0.

aka that patch is not the cause, and it just uncover other problems.

solution is trying to insert ioapic_resource early a little bit.

Reported-by: Stephen Frost <sfrost@snowman.net>
Reported-by: dann frazier <dannf@hp.com>
Signed-off-by: Yinghai Lu <yinghai@kernel.org>

---
 arch/x86/include/asm/io_apic.h |    2 ++
 arch/x86/kernel/apic/io_apic.c |   14 +++-----------
 arch/x86/pci/i386.c            |    7 +++++++
 3 files changed, 12 insertions(+), 11 deletions(-)

Index: linux-2.6/arch/x86/include/asm/io_apic.h
===================================================================
--- linux-2.6.orig/arch/x86/include/asm/io_apic.h
+++ linux-2.6/arch/x86/include/asm/io_apic.h
@@ -161,6 +161,7 @@ extern int io_apic_set_pci_routing(struc
 		 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,
 #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
Index: linux-2.6/arch/x86/kernel/apic/io_apic.c
===================================================================
--- linux-2.6.orig/arch/x86/kernel/apic/io_apic.c
+++ linux-2.6/arch/x86/kernel/apic/io_apic.c
@@ -4182,28 +4182,20 @@ fake_ioapic_page:
 	}
 }
 
-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);
Index: linux-2.6/arch/x86/pci/i386.c
===================================================================
--- linux-2.6.orig/arch/x86/pci/i386.c
+++ linux-2.6/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 we trying to assign unassigned pci res.
+	 */
+	ioapic_insert_resources();
 }
 
 /**