Merge master.kernel.org:/home/rmk/linux-2.6-arm

[pandora-kernel.git] / arch / x86_64 / kernel / mpparse.c

diff --git a/arch/x86_64/kernel/mpparse.c b/arch/x86_64/kernel/mpparse.c
index b17cf3e..083da7e 100644 (file)
--- a/arch/x86_64/kernel/mpparse.c
+++ b/arch/x86_64/kernel/mpparse.c
@@ -968,7 +968,17 @@ int mp_register_gsi(u32 gsi, int triggering, int polarity)
                 */
                int irq = gsi;
                if (gsi < MAX_GSI_NUM) {
-                       if (gsi > 15)
+                       /*
+                        * Retain the VIA chipset work-around (gsi > 15), but
+                        * avoid a problem where the 8254 timer (IRQ0) is setup
+                        * via an override (so it's not on pin 0 of the ioapic),
+                        * and at the same time, the pin 0 interrupt is a PCI
+                        * type.  The gsi > 15 test could cause these two pins
+                        * to be shared as IRQ0, and they are not shareable.
+                        * So test for this condition, and if necessary, avoid
+                        * the pin collision.
+                        */
+                       if (gsi > 15 || (gsi == 0 && !timer_uses_ioapic_pin_0))
                                gsi = pci_irq++;
                        /*
                         * Don't assign IRQ used by ACPI SCI