1 files changed, 62 insertions, 6 deletions

diff --git a/arch/powerpc/sysdev/mpic.c b/arch/powerpc/sysdev/mpic.c
index 8e3478c995ef..1890fb085cde 100644
--- a/arch/powerpc/sysdev/mpic.c
+++ b/arch/powerpc/sysdev/mpic.c
@@ -563,6 +563,51 @@ static void __init mpic_scan_ht_pics(struct mpic *mpic)
 
 #endif /* CONFIG_MPIC_U3_HT_IRQS */
 
+#ifdef CONFIG_SMP
+static int irq_choose_cpu(unsigned int virt_irq)
+{
+        cpumask_t mask = irq_desc[virt_irq].affinity;
+        int cpuid;
+
+        if (cpus_equal(mask, CPU_MASK_ALL)) {
+                static int irq_rover;
+                static DEFINE_SPINLOCK(irq_rover_lock);
+                unsigned long flags;
+
+                /* Round-robin distribution... */
+        do_round_robin:
+                spin_lock_irqsave(&irq_rover_lock, flags);
+
+                while (!cpu_online(irq_rover)) {
+                        if (++irq_rover >= NR_CPUS)
+                                irq_rover = 0;
+                }
+                cpuid = irq_rover;
+                do {
+                        if (++irq_rover >= NR_CPUS)
+                                irq_rover = 0;
+                } while (!cpu_online(irq_rover));
+
+                spin_unlock_irqrestore(&irq_rover_lock, flags);
+        } else {
+                cpumask_t tmp;
+
+                cpus_and(tmp, cpu_online_map, mask);
+
+                if (cpus_empty(tmp))
+                        goto do_round_robin;
+
+                cpuid = first_cpu(tmp);
+        }
+
+        return get_hard_smp_processor_id(cpuid);
+}
+#else
+static int irq_choose_cpu(unsigned int virt_irq)
+{
+        return hard_smp_processor_id();
+}
+#endif
 
 #define mpic_irq_to_hw(virq)    ((unsigned int)irq_map[virq].hwirq)
 
@@ -777,12 +822,18 @@ void mpic_set_affinity(unsigned int irq, cpumask_t cpumask)
         struct mpic *mpic = mpic_from_irq(irq);
         unsigned int src = mpic_irq_to_hw(irq);
 
-        cpumask_t tmp;
+        if (mpic->flags & MPIC_SINGLE_DEST_CPU) {
+                int cpuid = irq_choose_cpu(irq);
+
+                mpic_irq_write(src, MPIC_INFO(IRQ_DESTINATION), 1 << cpuid);
+        } else {
+                cpumask_t tmp;
 
-        cpus_and(tmp, cpumask, cpu_online_map);
+                cpus_and(tmp, cpumask, cpu_online_map);
 
-        mpic_irq_write(src, MPIC_INFO(IRQ_DESTINATION),
-                       mpic_physmask(cpus_addr(tmp)[0]));       
+                mpic_irq_write(src, MPIC_INFO(IRQ_DESTINATION),
+                               mpic_physmask(cpus_addr(tmp)[0]));
+        }
 }
 
 static unsigned int mpic_type_to_vecpri(struct mpic *mpic, unsigned int type)
@@ -1220,6 +1271,7 @@ void __init mpic_set_default_senses(struct mpic *mpic, u8 *senses, int count)
 void __init mpic_init(struct mpic *mpic)
 {
         int i;
+        int cpu;
 
         BUG_ON(mpic->num_sources == 0);
 
@@ -1262,6 +1314,11 @@ void __init mpic_init(struct mpic *mpic)
 
         mpic_pasemi_msi_init(mpic);
 
+        if (mpic->flags & MPIC_PRIMARY)
+                cpu = hard_smp_processor_id();
+        else
+                cpu = 0;
+
         for (i = 0; i < mpic->num_sources; i++) {
                 /* start with vector = source number, and masked */
                 u32 vecpri = MPIC_VECPRI_MASK | i |
@@ -1272,8 +1329,7 @@ void __init mpic_init(struct mpic *mpic)
                         continue;
                 /* init hw */
                 mpic_irq_write(i, MPIC_INFO(IRQ_VECTOR_PRI), vecpri);
-                mpic_irq_write(i, MPIC_INFO(IRQ_DESTINATION),
-                               1 << hard_smp_processor_id());
+                mpic_irq_write(i, MPIC_INFO(IRQ_DESTINATION), 1 << cpu);
         }
         
         /* Init spurious vector */