1 files changed, 25 insertions, 11 deletions

diff --git a/arch/powerpc/sysdev/mpic.c b/arch/powerpc/sysdev/mpic.c
index d5d3ff3d757e..8c7e8528e7c4 100644
--- a/arch/powerpc/sysdev/mpic.c
+++ b/arch/powerpc/sysdev/mpic.c
@@ -800,8 +800,6 @@ static void mpic_end_ipi(struct irq_data *d)
          * IPIs are marked IRQ_PER_CPU. This has the side effect of
          * preventing the IRQ_PENDING/IRQ_INPROGRESS logic from
          * applying to them. We EOI them late to avoid re-entering.
-         * We mark IPI's with IRQF_DISABLED as they must run with
-         * irqs disabled.
          */
         mpic_eoi(mpic);
 }
@@ -1285,13 +1283,11 @@ struct mpic * __init mpic_alloc(struct device_node *node,
                            mpic_read(mpic->gregs, MPIC_INFO(GREG_GLOBAL_CONF_0))
                            | MPIC_GREG_GCONF_MCK);
 
-        /* Read feature register, calculate num CPUs and, for non-ISU
-         * MPICs, num sources as well. On ISU MPICs, sources are counted
-         * as ISUs are added
+        /*
+         * Read feature register.  For non-ISU MPICs, num sources as well. On
+         * ISU MPICs, sources are counted as ISUs are added
          */
         greg_feature = mpic_read(mpic->gregs, MPIC_INFO(GREG_FEATURE_0));
-        mpic->num_cpus = ((greg_feature & MPIC_GREG_FEATURE_LAST_CPU_MASK)
-                          >> MPIC_GREG_FEATURE_LAST_CPU_SHIFT) + 1;
         if (isu_size == 0) {
                 if (flags & MPIC_BROKEN_FRR_NIRQS)
                         mpic->num_sources = mpic->irq_count;
@@ -1301,10 +1297,18 @@ struct mpic * __init mpic_alloc(struct device_node *node,
                                  >> MPIC_GREG_FEATURE_LAST_SRC_SHIFT) + 1;
         }
 
+        /*
+         * The MPIC driver will crash if there are more cores than we
+         * can initialize, so we may as well catch that problem here.
+         */
+        BUG_ON(num_possible_cpus() > MPIC_MAX_CPUS);
+
         /* Map the per-CPU registers */
-        for (i = 0; i < mpic->num_cpus; i++) {
-                mpic_map(mpic, node, paddr, &mpic->cpuregs[i],
-                         MPIC_INFO(CPU_BASE) + i * MPIC_INFO(CPU_STRIDE),
+        for_each_possible_cpu(i) {
+                unsigned int cpu = get_hard_smp_processor_id(i);
+
+                mpic_map(mpic, node, paddr, &mpic->cpuregs[cpu],
+                         MPIC_INFO(CPU_BASE) + cpu * MPIC_INFO(CPU_STRIDE),
                          0x1000);
         }
 
@@ -1343,7 +1347,7 @@ struct mpic * __init mpic_alloc(struct device_node *node,
         }
         printk(KERN_INFO "mpic: Setting up MPIC \"%s\" version %s at %llx,"
                " max %d CPUs\n",
-               name, vers, (unsigned long long)paddr, mpic->num_cpus);
+               name, vers, (unsigned long long)paddr, num_possible_cpus());
         printk(KERN_INFO "mpic: ISU size: %d, shift: %d, mask: %x\n",
                mpic->isu_size, mpic->isu_shift, mpic->isu_mask);
 
@@ -1742,6 +1746,7 @@ void mpic_reset_core(int cpu)
         struct mpic *mpic = mpic_primary;
         u32 pir;
         int cpuid = get_hard_smp_processor_id(cpu);
+        int i;
 
         /* Set target bit for core reset */
         pir = mpic_read(mpic->gregs, MPIC_INFO(GREG_PROCESSOR_INIT));
@@ -1753,6 +1758,15 @@ void mpic_reset_core(int cpu)
         pir &= ~(1 << cpuid);
         mpic_write(mpic->gregs, MPIC_INFO(GREG_PROCESSOR_INIT), pir);
         mpic_read(mpic->gregs, MPIC_INFO(GREG_PROCESSOR_INIT));
+
+        /* Perform 15 EOI on each reset core to clear pending interrupts.
+         * This is required for FSL CoreNet based devices */
+        if (mpic->flags & MPIC_FSL) {
+                for (i = 0; i < 15; i++) {
+                        _mpic_write(mpic->reg_type, &mpic->cpuregs[cpuid],
+                                      MPIC_CPU_EOI, 0);
+                }
+        }
 }
 #endif /* CONFIG_SMP */