6 files changed, 247 insertions, 467 deletions

diff --git a/arch/sparc64/kernel/entry.S b/arch/sparc64/kernel/entry.S
index eee516a71c14..d3973d8a7195 100644
--- a/arch/sparc64/kernel/entry.S
+++ b/arch/sparc64/kernel/entry.S
@@ -553,13 +553,11 @@ do_ivec:
         sllx            %g3, 5, %g3
         or              %g2, %lo(ivector_table), %g2
         add             %g2, %g3, %g3
-        ldx             [%g3 + 0x08], %g2       /* irq_info */
         ldub            [%g3 + 0x04], %g4       /* pil */
-        brz,pn          %g2, do_ivec_spurious
-         mov            1, %g2
-
+        mov             1, %g2
         sllx            %g2, %g4, %g2
         sllx            %g4, 2, %g4
+
         lduw            [%g6 + %g4], %g5        /* g5 = irq_work(cpu, pil) */
         stw             %g5, [%g3 + 0x00]       /* bucket->irq_chain = g5 */
         stw             %g3, [%g6 + %g4]        /* irq_work(cpu, pil) = bucket */
@@ -567,9 +565,9 @@ do_ivec:
         retry
 do_ivec_xcall:
         mov             0x50, %g1
-
         ldxa            [%g1 + %g0] ASI_INTR_R, %g1
         srl             %g3, 0, %g3
+
         mov             0x60, %g7
         ldxa            [%g7 + %g0] ASI_INTR_R, %g7
         stxa            %g0, [%g0] ASI_INTR_RECEIVE
@@ -581,19 +579,6 @@ do_ivec_xcall:
 1:      jmpl            %g3, %g0
          nop
 
-do_ivec_spurious:
-        stw             %g3, [%g6 + 0x00]       /* irq_work(cpu, 0) = bucket */
-        rdpr            %pstate, %g5
-
-        wrpr            %g5, PSTATE_IG | PSTATE_AG, %pstate
-        sethi           %hi(109f), %g7
-        ba,pt           %xcc, etrap
-109:     or             %g7, %lo(109b), %g7
-        call            catch_disabled_ivec
-         add            %sp, PTREGS_OFF, %o0
-        ba,pt           %xcc, rtrap
-         clr            %l6
-
         .globl          save_alternate_globals
 save_alternate_globals: /* %o0 = save_area */
         rdpr            %pstate, %o5
diff --git a/arch/sparc64/kernel/irq.c b/arch/sparc64/kernel/irq.c
index 424712577307..74a2e0808cbc 100644
--- a/arch/sparc64/kernel/irq.c
+++ b/arch/sparc64/kernel/irq.c
@@ -71,31 +71,7 @@ struct irq_work_struct {
 struct irq_work_struct __irq_work[NR_CPUS];
 #define irq_work(__cpu, __pil)  &(__irq_work[(__cpu)].irq_worklists[(__pil)])
 
-#ifdef CONFIG_PCI
-/* This is a table of physical addresses used to deal with IBF_DMA_SYNC.
- * It is used for PCI only to synchronize DMA transfers with IRQ delivery
- * for devices behind busses other than APB on Sabre systems.
- *
- * Currently these physical addresses are just config space accesses
- * to the command register for that device.
- */
-unsigned long pci_dma_wsync;
-unsigned long dma_sync_reg_table[256];
-unsigned char dma_sync_reg_table_entry = 0;
-#endif
-
-/* This is based upon code in the 32-bit Sparc kernel written mostly by
- * David Redman (djhr@tadpole.co.uk).
- */
-#define MAX_STATIC_ALLOC        4
-static struct irqaction static_irqaction[MAX_STATIC_ALLOC];
-static int static_irq_count;
-
-/* This is exported so that fast IRQ handlers can get at it... -DaveM */
-struct irqaction *irq_action[NR_IRQS+1] = {
-          NULL, NULL, NULL, NULL, NULL, NULL , NULL, NULL,
-          NULL, NULL, NULL, NULL, NULL, NULL , NULL, NULL
-};
+static struct irqaction *irq_action[NR_IRQS+1];
 
 /* This only synchronizes entities which modify IRQ handler
  * state and some selected user-level spots that want to
@@ -241,17 +217,22 @@ void disable_irq(unsigned int irq)
  * the CPU %tick register and not by some normal vectored interrupt
  * source.  To handle this special case, we use this dummy INO bucket.
  */
+static struct irq_desc pil0_dummy_desc;
 static struct ino_bucket pil0_dummy_bucket = {
-        0,      /* irq_chain */
-        0,      /* pil */
-        0,      /* pending */
-        0,      /* flags */
-        0,      /* __unused */
-        NULL,   /* irq_info */
-        0UL,    /* iclr */
-        0UL,    /* imap */
+        .irq_info       =       &pil0_dummy_desc,
 };
 
+static void build_irq_error(const char *msg, unsigned int ino, int pil, int inofixup,
+                            unsigned long iclr, unsigned long imap,
+                            struct ino_bucket *bucket)
+{
+        prom_printf("IRQ: INO %04x (%d:%016lx:%016lx) --> "
+                    "(%d:%d:%016lx:%016lx), halting...\n",
+                    ino, bucket->pil, bucket->iclr, bucket->imap,
+                    pil, inofixup, iclr, imap);
+        prom_halt();
+}
+
 unsigned int build_irq(int pil, int inofixup, unsigned long iclr, unsigned long imap)
 {
         struct ino_bucket *bucket;
@@ -280,28 +261,35 @@ unsigned int build_irq(int pil, int inofixup, unsigned long iclr, unsigned long
                 prom_halt();
         }
 
-        /* Ok, looks good, set it up.  Don't touch the irq_chain or
-         * the pending flag.
-         */
         bucket = &ivector_table[ino];
-        if ((bucket->flags & IBF_ACTIVE) ||
-            (bucket->irq_info != NULL)) {
-                /* This is a gross fatal error if it happens here. */
-                prom_printf("IRQ: Trying to reinit INO bucket, fatal error.\n");
-                prom_printf("IRQ: Request INO %04x (%d:%d:%016lx:%016lx)\n",
-                            ino, pil, inofixup, iclr, imap);
-                prom_printf("IRQ: Existing (%d:%016lx:%016lx)\n",
-                            bucket->pil, bucket->iclr, bucket->imap);
-                prom_printf("IRQ: Cannot continue, halting...\n");
+        if (bucket->flags & IBF_ACTIVE)
+                build_irq_error("IRQ: Trying to build active INO bucket.\n",
+                                ino, pil, inofixup, iclr, imap, bucket);
+
+        if (bucket->irq_info) {
+                if (bucket->imap != imap || bucket->iclr != iclr)
+                        build_irq_error("IRQ: Trying to reinit INO bucket.\n",
+                                        ino, pil, inofixup, iclr, imap, bucket);
+
+                goto out;
+        }
+
+        bucket->irq_info = kmalloc(sizeof(struct irq_desc), GFP_ATOMIC);
+        if (!bucket->irq_info) {
+                prom_printf("IRQ: Error, kmalloc(irq_desc) failed.\n");
                 prom_halt();
         }
+        memset(bucket->irq_info, 0, sizeof(struct irq_desc));
+
+        /* Ok, looks good, set it up.  Don't touch the irq_chain or
+         * the pending flag.
+         */
         bucket->imap  = imap;
         bucket->iclr  = iclr;
         bucket->pil   = pil;
         bucket->flags = 0;
 
-        bucket->irq_info = NULL;
-
+out:
         return __irq(bucket);
 }
 
@@ -319,26 +307,65 @@ static void atomic_bucket_insert(struct ino_bucket *bucket)
         __asm__ __volatile__("wrpr %0, 0x0, %%pstate" : : "r" (pstate));
 }
 
+static int check_irq_sharing(int pil, unsigned long irqflags)
+{
+        struct irqaction *action, *tmp;
+
+        action = *(irq_action + pil);
+        if (action) {
+                if ((action->flags & SA_SHIRQ) && (irqflags & SA_SHIRQ)) {
+                        for (tmp = action; tmp->next; tmp = tmp->next)
+                                ;
+                } else {
+                        return -EBUSY;
+                }
+        }
+        return 0;
+}
+
+static void append_irq_action(int pil, struct irqaction *action)
+{
+        struct irqaction **pp = irq_action + pil;
+
+        while (*pp)
+                pp = &((*pp)->next);
+        *pp = action;
+}
+
+static struct irqaction *get_action_slot(struct ino_bucket *bucket)
+{
+        struct irq_desc *desc = bucket->irq_info;
+        int max_irq, i;
+
+        max_irq = 1;
+        if (bucket->flags & IBF_PCI)
+                max_irq = MAX_IRQ_DESC_ACTION;
+        for (i = 0; i < max_irq; i++) {
+                struct irqaction *p = &desc->action[i];
+                u32 mask = (1 << i);
+
+                if (desc->action_active_mask & mask)
+                        continue;
+
+                desc->action_active_mask |= mask;
+                return p;
+        }
+        return NULL;
+}
+
 int request_irq(unsigned int irq, irqreturn_t (*handler)(int, void *, struct pt_regs *),
                 unsigned long irqflags, const char *name, void *dev_id)
 {
-        struct irqaction *action, *tmp = NULL;
+        struct irqaction *action;
         struct ino_bucket *bucket = __bucket(irq);
         unsigned long flags;
         int pending = 0;
 
-        if ((bucket != &pil0_dummy_bucket) &&
-            (bucket < &ivector_table[0] ||
-             bucket >= &ivector_table[NUM_IVECS])) {
-                unsigned int *caller;
-
-                __asm__ __volatile__("mov %%i7, %0" : "=r" (caller));
-                printk(KERN_CRIT "request_irq: Old style IRQ registry attempt "
-                       "from %p, irq %08x.\n", caller, irq);
+        if (unlikely(!handler))
                 return -EINVAL;
-        }       
-        if (!handler)
-            return -EINVAL;
+
+        if (unlikely(!bucket->irq_info))
+                return -ENODEV;
 
         if ((bucket != &pil0_dummy_bucket) && (irqflags & SA_SAMPLE_RANDOM)) {
                 /*
@@ -356,93 +383,20 @@ int request_irq(unsigned int irq, irqreturn_t (*handler)(int, void *, struct pt_
 
         spin_lock_irqsave(&irq_action_lock, flags);
 
-        action = *(bucket->pil + irq_action);
-        if (action) {
-                if ((action->flags & SA_SHIRQ) && (irqflags & SA_SHIRQ))
-                        for (tmp = action; tmp->next; tmp = tmp->next)
-                                ;
-                else {
-                        spin_unlock_irqrestore(&irq_action_lock, flags);
-                        return -EBUSY;
-                }
-                action = NULL;          /* Or else! */
+        if (check_irq_sharing(bucket->pil, irqflags)) {
+                spin_unlock_irqrestore(&irq_action_lock, flags);
+                return -EBUSY;
         }
 
-        /* If this is flagged as statically allocated then we use our
-         * private struct which is never freed.
-         */
-        if (irqflags & SA_STATIC_ALLOC) {
-            if (static_irq_count < MAX_STATIC_ALLOC)
-                action = &static_irqaction[static_irq_count++];
-            else
-                printk("Request for IRQ%d (%s) SA_STATIC_ALLOC failed "
-                       "using kmalloc\n", irq, name);
-        }       
-        if (action == NULL)
-            action = (struct irqaction *)kmalloc(sizeof(struct irqaction),
-                                                 GFP_ATOMIC);
-        
+        action = get_action_slot(bucket);
         if (!action) { 
                 spin_unlock_irqrestore(&irq_action_lock, flags);
                 return -ENOMEM;
         }
 
-        if (bucket == &pil0_dummy_bucket) {
-                bucket->irq_info = action;
-                bucket->flags |= IBF_ACTIVE;
-        } else {
-                if ((bucket->flags & IBF_ACTIVE) != 0) {
-                        void *orig = bucket->irq_info;
-                        void **vector = NULL;
-
-                        if ((bucket->flags & IBF_PCI) == 0) {
-                                printk("IRQ: Trying to share non-PCI bucket.\n");
-                                goto free_and_ebusy;
-                        }
-                        if ((bucket->flags & IBF_MULTI) == 0) {
-                                vector = kmalloc(sizeof(void *) * 4, GFP_ATOMIC);
-                                if (vector == NULL)
-                                        goto free_and_enomem;
-
-                                /* We might have slept. */
-                                if ((bucket->flags & IBF_MULTI) != 0) {
-                                        int ent;
-
-                                        kfree(vector);
-                                        vector = (void **)bucket->irq_info;
-                                        for(ent = 0; ent < 4; ent++) {
-                                                if (vector[ent] == NULL) {
-                                                        vector[ent] = action;
-                                                        break;
-                                                }
-                                        }
-                                        if (ent == 4)
-                                                goto free_and_ebusy;
-                                } else {
-                                        vector[0] = orig;
-                                        vector[1] = action;
-                                        vector[2] = NULL;
-                                        vector[3] = NULL;
-                                        bucket->irq_info = vector;
-                                        bucket->flags |= IBF_MULTI;
-                                }
-                        } else {
-                                int ent;
-
-                                vector = (void **)orig;
-                                for (ent = 0; ent < 4; ent++) {
-                                        if (vector[ent] == NULL) {
-                                                vector[ent] = action;
-                                                break;
-                                        }
-                                }
-                                if (ent == 4)
-                                        goto free_and_ebusy;
-                        }
-                } else {
-                        bucket->irq_info = action;
-                        bucket->flags |= IBF_ACTIVE;
-                }
+        bucket->flags |= IBF_ACTIVE;
+        pending = 0;
+        if (bucket != &pil0_dummy_bucket) {
                 pending = bucket->pending;
                 if (pending)
                         bucket->pending = 0;
@@ -456,10 +410,7 @@ int request_irq(unsigned int irq, irqreturn_t (*handler)(int, void *, struct pt_
         put_ino_in_irqaction(action, irq);
         put_smpaff_in_irqaction(action, CPU_MASK_NONE);
 
-        if (tmp)
-                tmp->next = action;
-        else
-                *(bucket->pil + irq_action) = action;
+        append_irq_action(bucket->pil, action);
 
         enable_irq(irq);
 
@@ -468,147 +419,103 @@ int request_irq(unsigned int irq, irqreturn_t (*handler)(int, void *, struct pt_
                 atomic_bucket_insert(bucket);
                 set_softint(1 << bucket->pil);
         }
+
         spin_unlock_irqrestore(&irq_action_lock, flags);
-        if ((bucket != &pil0_dummy_bucket) && (!(irqflags & SA_STATIC_ALLOC)))
+
+        if (bucket != &pil0_dummy_bucket)
                 register_irq_proc(__irq_ino(irq));
 
 #ifdef CONFIG_SMP
         distribute_irqs();
 #endif
         return 0;
-
-free_and_ebusy:
-        kfree(action);
-        spin_unlock_irqrestore(&irq_action_lock, flags);
-        return -EBUSY;
-
-free_and_enomem:
-        kfree(action);
-        spin_unlock_irqrestore(&irq_action_lock, flags);
-        return -ENOMEM;
 }
 
 EXPORT_SYMBOL(request_irq);
 
-void free_irq(unsigned int irq, void *dev_id)
+static struct irqaction *unlink_irq_action(unsigned int irq, void *dev_id)
 {
-        struct irqaction *action;
-        struct irqaction *tmp = NULL;
-        unsigned long flags;
-        struct ino_bucket *bucket = __bucket(irq), *bp;
-
-        if ((bucket != &pil0_dummy_bucket) &&
-            (bucket < &ivector_table[0] ||
-             bucket >= &ivector_table[NUM_IVECS])) {
-                unsigned int *caller;
+        struct ino_bucket *bucket = __bucket(irq);
+        struct irqaction *action, **pp;
 
-                __asm__ __volatile__("mov %%i7, %0" : "=r" (caller));
-                printk(KERN_CRIT "free_irq: Old style IRQ removal attempt "
-                       "from %p, irq %08x.\n", caller, irq);
-                return;
-        }
-        
-        spin_lock_irqsave(&irq_action_lock, flags);
+        pp = irq_action + bucket->pil;
+        action = *pp;
+        if (unlikely(!action))
+                return NULL;
 
-        action = *(bucket->pil + irq_action);
-        if (!action->handler) {
+        if (unlikely(!action->handler)) {
                 printk("Freeing free IRQ %d\n", bucket->pil);
-                return;
-        }
-        if (dev_id) {
-                for ( ; action; action = action->next) {
-                        if (action->dev_id == dev_id)
-                                break;
-                        tmp = action;
-                }
-                if (!action) {
-                        printk("Trying to free free shared IRQ %d\n", bucket->pil);
-                        spin_unlock_irqrestore(&irq_action_lock, flags);
-                        return;
-                }
-        } else if (action->flags & SA_SHIRQ) {
-                printk("Trying to free shared IRQ %d with NULL device ID\n", bucket->pil);
-                spin_unlock_irqrestore(&irq_action_lock, flags);
-                return;
+                return NULL;
         }
 
-        if (action->flags & SA_STATIC_ALLOC) {
-                printk("Attempt to free statically allocated IRQ %d (%s)\n",
-                       bucket->pil, action->name);
-                spin_unlock_irqrestore(&irq_action_lock, flags);
-                return;
+        while (action && action->dev_id != dev_id) {
+                pp = &action->next;
+                action = *pp;
         }
 
-        if (action && tmp)
-                tmp->next = action->next;
-        else
-                *(bucket->pil + irq_action) = action->next;
+        if (likely(action))
+                *pp = action->next;
+
+        return action;
+}
+
+void free_irq(unsigned int irq, void *dev_id)
+{
+        struct irqaction *action;
+        struct ino_bucket *bucket;
+        unsigned long flags;
+
+        spin_lock_irqsave(&irq_action_lock, flags);
+
+        action = unlink_irq_action(irq, dev_id);
 
         spin_unlock_irqrestore(&irq_action_lock, flags);
 
+        if (unlikely(!action))
+                return;
+
         synchronize_irq(irq);
 
         spin_lock_irqsave(&irq_action_lock, flags);
 
+        bucket = __bucket(irq);
         if (bucket != &pil0_dummy_bucket) {
+                struct irq_desc *desc = bucket->irq_info;
                 unsigned long imap = bucket->imap;
-                void **vector, *orig;
-                int ent;
-
-                orig = bucket->irq_info;
-                vector = (void **)orig;
-
-                if ((bucket->flags & IBF_MULTI) != 0) {
-                        int other = 0;
-                        void *orphan = NULL;
-                        for (ent = 0; ent < 4; ent++) {
-                                if (vector[ent] == action)
-                                        vector[ent] = NULL;
-                                else if (vector[ent] != NULL) {
-                                        orphan = vector[ent];
-                                        other++;
-                                }
-                        }
+                int ent, i;
 
-                        /* Only free when no other shared irq
-                         * uses this bucket.
-                         */
-                        if (other) {
-                                if (other == 1) {
-                                        /* Convert back to non-shared bucket. */
-                                        bucket->irq_info = orphan;
-                                        bucket->flags &= ~(IBF_MULTI);
-                                        kfree(vector);
-                                }
-                                goto out;
+                for (i = 0; i < MAX_IRQ_DESC_ACTION; i++) {
+                        struct irqaction *p = &desc->action[i];
+
+                        if (p == action) {
+                                desc->action_active_mask &= ~(1 << i);
+                                break;
                         }
-                } else {
-                        bucket->irq_info = NULL;
                 }
 
-                /* This unique interrupt source is now inactive. */
-                bucket->flags &= ~IBF_ACTIVE;
+                if (!desc->action_active_mask) {
+                        /* This unique interrupt source is now inactive. */
+                        bucket->flags &= ~IBF_ACTIVE;
 
-                /* See if any other buckets share this bucket's IMAP
-                 * and are still active.
-                 */
-                for (ent = 0; ent < NUM_IVECS; ent++) {
-                        bp = &ivector_table[ent];
-                        if (bp != bucket        &&
-                            bp->imap == imap    &&
-                            (bp->flags & IBF_ACTIVE) != 0)
-                                break;
-                }
+                        /* See if any other buckets share this bucket's IMAP
+                         * and are still active.
+                         */
+                        for (ent = 0; ent < NUM_IVECS; ent++) {
+                                struct ino_bucket *bp = &ivector_table[ent];
+                                if (bp != bucket        &&
+                                    bp->imap == imap    &&
+                                    (bp->flags & IBF_ACTIVE) != 0)
+                                        break;
+                        }
 
-                /* Only disable when no other sub-irq levels of
-                 * the same IMAP are active.
-                 */
-                if (ent == NUM_IVECS)
-                        disable_irq(irq);
+                        /* Only disable when no other sub-irq levels of
+                         * the same IMAP are active.
+                         */
+                        if (ent == NUM_IVECS)
+                                disable_irq(irq);
+                }
         }
 
-out:
-        kfree(action);
         spin_unlock_irqrestore(&irq_action_lock, flags);
 }
 
@@ -647,99 +554,55 @@ void synchronize_irq(unsigned int irq)
 }
 #endif /* CONFIG_SMP */
 
-void catch_disabled_ivec(struct pt_regs *regs)
-{
-        int cpu = smp_processor_id();
-        struct ino_bucket *bucket = __bucket(*irq_work(cpu, 0));
-
-        /* We can actually see this on Ultra/PCI PCI cards, which are bridges
-         * to other devices.  Here a single IMAP enabled potentially multiple
-         * unique interrupt sources (which each do have a unique ICLR register.
-         *
-         * So what we do is just register that the IVEC arrived, when registered
-         * for real the request_irq() code will check the bit and signal
-         * a local CPU interrupt for it.
-         */
-#if 0
-        printk("IVEC: Spurious interrupt vector (%x) received at (%016lx)\n",
-               bucket - &ivector_table[0], regs->tpc);
-#endif
-        *irq_work(cpu, 0) = 0;
-        bucket->pending = 1;
-}
-
-/* Tune this... */
-#define FORWARD_VOLUME          12
-
-#ifdef CONFIG_SMP
-
-static inline void redirect_intr(int cpu, struct ino_bucket *bp)
+static void process_bucket(int irq, struct ino_bucket *bp, struct pt_regs *regs)
 {
-        /* Ok, here is what is going on:
-         * 1) Retargeting IRQs on Starfire is very
-         *    expensive so just forget about it on them.
-         * 2) Moving around very high priority interrupts
-         *    is a losing game.
-         * 3) If the current cpu is idle, interrupts are
-         *    useful work, so keep them here.  But do not
-         *    pass to our neighbour if he is not very idle.
-         * 4) If sysadmin explicitly asks for directed intrs,
-         *    Just Do It.
-         */
-        struct irqaction *ap = bp->irq_info;
-        cpumask_t cpu_mask;
-        unsigned int buddy, ticks;
+        struct irq_desc *desc = bp->irq_info;
+        unsigned char flags = bp->flags;
+        u32 action_mask, i;
+        int random;
 
-        cpu_mask = get_smpaff_in_irqaction(ap);
-        cpus_and(cpu_mask, cpu_mask, cpu_online_map);
-        if (cpus_empty(cpu_mask))
-                cpu_mask = cpu_online_map;
+        bp->flags |= IBF_INPROGRESS;
 
-        if (this_is_starfire != 0 ||
-            bp->pil >= 10 || current->pid == 0)
+        if (unlikely(!(flags & IBF_ACTIVE))) {
+                bp->pending = 1;
                 goto out;
-
-        /* 'cpu' is the MID (ie. UPAID), calculate the MID
-         * of our buddy.
-         */
-        buddy = cpu + 1;
-        if (buddy >= NR_CPUS)
-                buddy = 0;
-
-        ticks = 0;
-        while (!cpu_isset(buddy, cpu_mask)) {
-                if (++buddy >= NR_CPUS)
-                        buddy = 0;
-                if (++ticks > NR_CPUS) {
-                        put_smpaff_in_irqaction(ap, CPU_MASK_NONE);
-                        goto out;
-                }
         }
 
-        if (buddy == cpu)
-                goto out;
+        if (desc->pre_handler)
+                desc->pre_handler(bp,
+                                  desc->pre_handler_arg1,
+                                  desc->pre_handler_arg2);
 
-        /* Voo-doo programming. */
-        if (cpu_data(buddy).idle_volume < FORWARD_VOLUME)
-                goto out;
+        action_mask = desc->action_active_mask;
+        random = 0;
+        for (i = 0; i < MAX_IRQ_DESC_ACTION; i++) {
+                struct irqaction *p = &desc->action[i];
+                u32 mask = (1 << i);
 
-        /* This just so happens to be correct on Cheetah
-         * at the moment.
-         */
-        buddy <<= 26;
+                if (!(action_mask & mask))
+                        continue;
+
+                action_mask &= ~mask;
 
-        /* Push it to our buddy. */
-        upa_writel(buddy | IMAP_VALID, bp->imap);
+                if (p->handler(__irq(bp), p->dev_id, regs) == IRQ_HANDLED)
+                        random |= p->flags;
 
+                if (!action_mask)
+                        break;
+        }
+        if (bp->pil != 0) {
+                upa_writel(ICLR_IDLE, bp->iclr);
+                /* Test and add entropy */
+                if (random & SA_SAMPLE_RANDOM)
+                        add_interrupt_randomness(irq);
+        }
 out:
-        return;
+        bp->flags &= ~IBF_INPROGRESS;
 }
 
-#endif
-
 void handler_irq(int irq, struct pt_regs *regs)
 {
-        struct ino_bucket *bp, *nbp;
+        struct ino_bucket *bp;
         int cpu = smp_processor_id();
 
 #ifndef CONFIG_SMP
@@ -757,8 +620,6 @@ void handler_irq(int irq, struct pt_regs *regs)
                 clear_softint(clr_mask);
         }
 #else
-        int should_forward = 0;
-
         clear_softint(1 << irq);
 #endif
 
@@ -773,63 +634,12 @@ void handler_irq(int irq, struct pt_regs *regs)
 #else
         bp = __bucket(xchg32(irq_work(cpu, irq), 0));
 #endif
-        for ( ; bp != NULL; bp = nbp) {
-                unsigned char flags = bp->flags;
-                unsigned char random = 0;
+        while (bp) {
+                struct ino_bucket *nbp = __bucket(bp->irq_chain);
 
-                nbp = __bucket(bp->irq_chain);
                 bp->irq_chain = 0;
-
-                bp->flags |= IBF_INPROGRESS;
-
-                if ((flags & IBF_ACTIVE) != 0) {
-#ifdef CONFIG_PCI
-                        if ((flags & IBF_DMA_SYNC) != 0) {
-                                upa_readl(dma_sync_reg_table[bp->synctab_ent]);
-                                upa_readq(pci_dma_wsync);
-                        }
-#endif
-                        if ((flags & IBF_MULTI) == 0) {
-                                struct irqaction *ap = bp->irq_info;
-                                int ret;
-
-                                ret = ap->handler(__irq(bp), ap->dev_id, regs);
-                                if (ret == IRQ_HANDLED)
-                                        random |= ap->flags;
-                        } else {
-                                void **vector = (void **)bp->irq_info;
-                                int ent;
-                                for (ent = 0; ent < 4; ent++) {
-                                        struct irqaction *ap = vector[ent];
-                                        if (ap != NULL) {
-                                                int ret;
-
-                                                ret = ap->handler(__irq(bp),
-                                                                  ap->dev_id,
-                                                                  regs);
-                                                if (ret == IRQ_HANDLED)
-                                                        random |= ap->flags;
-                                        }
-                                }
-                        }
-                        /* Only the dummy bucket lacks IMAP/ICLR. */
-                        if (bp->pil != 0) {
-#ifdef CONFIG_SMP
-                                if (should_forward) {
-                                        redirect_intr(cpu, bp);
-                                        should_forward = 0;
-                                }
-#endif
-                                upa_writel(ICLR_IDLE, bp->iclr);
-
-                                /* Test and add entropy */
-                                if (random & SA_SAMPLE_RANDOM)
-                                        add_interrupt_randomness(irq);
-                        }
-                } else
-                        bp->pending = 1;
-
-                bp->flags &= ~IBF_INPROGRESS;
+                process_bucket(irq, bp, regs);
+                bp = nbp;
         }
         irq_exit();
 }
@@ -959,7 +769,10 @@ static void distribute_irqs(void)
          */
         for (level = 1; level < NR_IRQS; level++) {
                 struct irqaction *p = irq_action[level];
-                if (level == 12) continue;
+
+                if (level == 12)
+                        continue;
+
                 while(p) {
                         cpu = retarget_one_irq(p, cpu);
                         p = p->next;
diff --git a/arch/sparc64/kernel/pci_sabre.c b/arch/sparc64/kernel/pci_sabre.c
index 53d333b4a4e8..52bf3431a422 100644
--- a/arch/sparc64/kernel/pci_sabre.c
+++ b/arch/sparc64/kernel/pci_sabre.c
@@ -595,6 +595,23 @@ static int __init sabre_ino_to_pil(struct pci_dev *pdev, unsigned int ino)
         return ret;
 }
 
+/* When a device lives behind a bridge deeper in the PCI bus topology
+ * than APB, a special sequence must run to make sure all pending DMA
+ * transfers at the time of IRQ delivery are visible in the coherency
+ * domain by the cpu.  This sequence is to perform a read on the far
+ * side of the non-APB bridge, then perform a read of Sabre's DMA
+ * write-sync register.
+ */
+static void sabre_wsync_handler(struct ino_bucket *bucket, void *_arg1, void *_arg2)
+{
+        struct pci_dev *pdev = _arg1;
+        unsigned long sync_reg = (unsigned long) _arg2;
+        u16 _unused;
+
+        pci_read_config_word(pdev, PCI_VENDOR_ID, &_unused);
+        sabre_read(sync_reg);
+}
+
 static unsigned int __init sabre_irq_build(struct pci_pbm_info *pbm,
                                            struct pci_dev *pdev,
                                            unsigned int ino)
@@ -639,24 +656,14 @@ static unsigned int __init sabre_irq_build(struct pci_pbm_info *pbm,
         if (pdev) {
                 struct pcidev_cookie *pcp = pdev->sysdata;
 
-                /* When a device lives behind a bridge deeper in the
-                 * PCI bus topology than APB, a special sequence must
-                 * run to make sure all pending DMA transfers at the
-                 * time of IRQ delivery are visible in the coherency
-                 * domain by the cpu.  This sequence is to perform
-                 * a read on the far side of the non-APB bridge, then
-                 * perform a read of Sabre's DMA write-sync register.
-                 *
-                 * Currently, the PCI_CONFIG register for the device
-                 * is used for this read from the far side of the bridge.
-                 */
                 if (pdev->bus->number != pcp->pbm->pci_first_busno) {
-                        bucket->flags |= IBF_DMA_SYNC;
-                        bucket->synctab_ent = dma_sync_reg_table_entry++;
-                        dma_sync_reg_table[bucket->synctab_ent] =
-                                (unsigned long) sabre_pci_config_mkaddr(
-                                        pcp->pbm,
-                                        pdev->bus->number, pdev->devfn, PCI_COMMAND);
+                        struct pci_controller_info *p = pcp->pbm->parent;
+                        struct irq_desc *d = bucket->irq_info;
+
+                        d->pre_handler = sabre_wsync_handler;
+                        d->pre_handler_arg1 = pdev;
+                        d->pre_handler_arg2 = (void *)
+                                p->pbm_A.controller_regs + SABRE_WRSYNC;
                 }
         }
         return __irq(bucket);
@@ -1626,10 +1633,9 @@ void __init sabre_init(int pnode, char *model_name)
          */
         p->pbm_A.controller_regs = pr_regs[0].phys_addr;
         p->pbm_B.controller_regs = pr_regs[0].phys_addr;
-        pci_dma_wsync = p->pbm_A.controller_regs + SABRE_WRSYNC;
 
-        printk("PCI: Found SABRE, main regs at %016lx, wsync at %016lx\n",
-               p->pbm_A.controller_regs, pci_dma_wsync);
+        printk("PCI: Found SABRE, main regs at %016lx\n",
+               p->pbm_A.controller_regs);
 
         /* Clear interrupts */
 
diff --git a/arch/sparc64/kernel/time.c b/arch/sparc64/kernel/time.c
index 71b4e3807694..b40db389f90b 100644
--- a/arch/sparc64/kernel/time.c
+++ b/arch/sparc64/kernel/time.c
@@ -973,7 +973,7 @@ static void sparc64_start_timers(irqreturn_t (*cfunc)(int, void *, struct pt_reg
         int err;
 
         /* Register IRQ handler. */
-        err = request_irq(build_irq(0, 0, 0UL, 0UL), cfunc, SA_STATIC_ALLOC,
+        err = request_irq(build_irq(0, 0, 0UL, 0UL), cfunc, 0,
                           "timer", NULL);
 
         if (err) {
diff --git a/include/asm-sparc64/irq.h b/include/asm-sparc64/irq.h
index 018e2e46082b..8b70edcb80dc 100644
--- a/include/asm-sparc64/irq.h
+++ b/include/asm-sparc64/irq.h
@@ -16,6 +16,18 @@
 #include <asm/pil.h>
 #include <asm/ptrace.h>
 
+struct ino_bucket;
+
+#define MAX_IRQ_DESC_ACTION     4
+
+struct irq_desc {
+        void                    (*pre_handler)(struct ino_bucket *, void *, void *);
+        void                    *pre_handler_arg1;
+        void                    *pre_handler_arg2;
+        u32                     action_active_mask;
+        struct irqaction        action[MAX_IRQ_DESC_ACTION];
+};
+
 /* You should not mess with this directly. That's the job of irq.c.
  *
  * If you make changes here, please update hand coded assembler of
@@ -42,24 +54,11 @@ struct ino_bucket {
         /* Miscellaneous flags. */
 /*0x06*/unsigned char flags;
 
-        /* This is used to deal with IBF_DMA_SYNC on
-         * Sabre systems.
-         */
-/*0x07*/unsigned char synctab_ent;
-
-        /* Reference to handler for this IRQ.  If this is
-         * non-NULL this means it is active and should be
-         * serviced.  Else the pending member is set to one
-         * and later registry of the interrupt checks for
-         * this condition.
-         *
-         * Normally this is just an irq_action structure.
-         * But, on PCI, if multiple interrupt sources behind
-         * a bridge have multiple interrupt sources that share
-         * the same INO bucket, this points to an array of
-         * pointers to four IRQ action structures.
-         */
-/*0x08*/void *irq_info;
+        /* Currently unused.  */
+/*0x07*/unsigned char __pad;
+
+        /* Reference to IRQ descriptor for this bucket. */
+/*0x08*/struct irq_desc *irq_info;
 
         /* Sun5 Interrupt Clear Register. */
 /*0x10*/unsigned long iclr;
@@ -69,12 +68,6 @@ struct ino_bucket {
 
 };
 
-#ifdef CONFIG_PCI
-extern unsigned long pci_dma_wsync;
-extern unsigned long dma_sync_reg_table[256];
-extern unsigned char dma_sync_reg_table_entry;
-#endif
-
 /* IMAP/ICLR register defines */
 #define IMAP_VALID              0x80000000      /* IRQ Enabled          */
 #define IMAP_TID_UPA            0x7c000000      /* UPA TargetID         */
@@ -90,11 +83,9 @@ extern unsigned char dma_sync_reg_table_entry;
 #define ICLR_PENDING            0x00000003      /* Pending state        */
 
 /* Only 8-bits are available, be careful.  -DaveM */
-#define IBF_DMA_SYNC    0x01    /* DMA synchronization behind PCI bridge needed. */
-#define IBF_PCI         0x02    /* Indicates PSYCHO/SABRE/SCHIZO PCI interrupt.  */
-#define IBF_ACTIVE      0x04    /* This interrupt is active and has a handler.   */
-#define IBF_MULTI       0x08    /* On PCI, indicates shared bucket.              */
-#define IBF_INPROGRESS  0x10    /* IRQ is being serviced.                        */
+#define IBF_PCI         0x02    /* PSYCHO/SABRE/SCHIZO PCI interrupt.    */
+#define IBF_ACTIVE      0x04    /* Interrupt is active and has a handler.*/
+#define IBF_INPROGRESS  0x10    /* IRQ is being serviced.                */
 
 #define NUM_IVECS       (IMAP_INR + 1)
 extern struct ino_bucket ivector_table[NUM_IVECS];
diff --git a/include/asm-sparc64/signal.h b/include/asm-sparc64/signal.h
index becdf1bc5924..e3059bb4a465 100644
--- a/include/asm-sparc64/signal.h
+++ b/include/asm-sparc64/signal.h
@@ -162,21 +162,6 @@ struct sigstack {
 #define MINSIGSTKSZ     4096
 #define SIGSTKSZ        16384
 
-#ifdef __KERNEL__
-/*
- * DJHR
- * SA_STATIC_ALLOC is used for the SPARC system to indicate that this
- * interrupt handler's irq structure should be statically allocated
- * by the request_irq routine.
- * The alternative is that arch/sparc/kernel/irq.c has carnal knowledge
- * of interrupt usage and that sucks. Also without a flag like this
- * it may be possible for the free_irq routine to attempt to free
- * statically allocated data.. which is NOT GOOD.
- *
- */
-#define SA_STATIC_ALLOC         0x80
-#endif
-
 #include <asm-generic/signal.h>
 
 struct __new_sigaction {