1 files changed, 296 insertions, 228 deletions

diff --git a/arch/ia64/sn/kernel/irq.c b/arch/ia64/sn/kernel/irq.c
index 0f4e8138658..85d09515490 100644
--- a/arch/ia64/sn/kernel/irq.c
+++ b/arch/ia64/sn/kernel/irq.c
@@ -5,30 +5,33 @@
  * License.  See the file "COPYING" in the main directory of this archive
  * for more details.
  *
- * Copyright (c) 2000-2004 Silicon Graphics, Inc.  All Rights Reserved.
+ * Copyright (c) 2000-2008 Silicon Graphics, Inc.  All Rights Reserved.
  */
 
 #include <linux/irq.h>
-#include <asm/sn/intr.h>
+#include <linux/spinlock.h>
+#include <linux/init.h>
+#include <linux/rculist.h>
+#include <linux/slab.h>
 #include <asm/sn/addrs.h>
 #include <asm/sn/arch.h>
-#include "xtalk/xwidgetdev.h"
+#include <asm/sn/intr.h>
+#include <asm/sn/pcibr_provider.h>
 #include <asm/sn/pcibus_provider_defs.h>
 #include <asm/sn/pcidev.h>
-#include "pci/pcibr_provider.h"
 #include <asm/sn/shub_mmr.h>
 #include <asm/sn/sn_sal.h>
+#include <asm/sn/sn_feature_sets.h>
 
-static void force_interrupt(int irq);
 static void register_intr_pda(struct sn_irq_info *sn_irq_info);
 static void unregister_intr_pda(struct sn_irq_info *sn_irq_info);
 
-extern int sn_force_interrupt_flag;
 extern int sn_ioif_inited;
-struct sn_irq_info **sn_irq;
+struct list_head **sn_irq_lh;
+static DEFINE_SPINLOCK(sn_irq_info_lock); /* non-IRQ lock */
 
-static inline uint64_t sn_intr_alloc(nasid_t local_nasid, int local_widget,
-				     u64 sn_irq_info,
+u64 sn_intr_alloc(nasid_t local_nasid, int local_widget,
+				     struct sn_irq_info *sn_irq_info,
 				     int req_irq, nasid_t req_nasid,
 				     int req_slice)
 {
@@ -38,12 +41,13 @@ static inline uint64_t sn_intr_alloc(nasid_t local_nasid, int local_widget,
 
 	SAL_CALL_NOLOCK(ret_stuff, (u64) SN_SAL_IOIF_INTERRUPT,
 			(u64) SAL_INTR_ALLOC, (u64) local_nasid,
-			(u64) local_widget, (u64) sn_irq_info, (u64) req_irq,
+			(u64) local_widget, __pa(sn_irq_info), (u64) req_irq,
 			(u64) req_nasid, (u64) req_slice);
+
 	return ret_stuff.status;
 }
 
-static inline void sn_intr_free(nasid_t local_nasid, int local_widget,
+void sn_intr_free(nasid_t local_nasid, int local_widget,
 				struct sn_irq_info *sn_irq_info)
 {
 	struct ia64_sal_retval ret_stuff;
@@ -56,143 +60,208 @@ static inline void sn_intr_free(nasid_t local_nasid, int local_widget,
 			(u64) sn_irq_info->irq_cookie, 0, 0);
 }
 
-static unsigned int sn_startup_irq(unsigned int irq)
+u64 sn_intr_redirect(nasid_t local_nasid, int local_widget,
+		      struct sn_irq_info *sn_irq_info,
+		      nasid_t req_nasid, int req_slice)
+{
+	struct ia64_sal_retval ret_stuff;
+	ret_stuff.status = 0;
+	ret_stuff.v0 = 0;
+
+	SAL_CALL_NOLOCK(ret_stuff, (u64) SN_SAL_IOIF_INTERRUPT,
+			(u64) SAL_INTR_REDIRECT, (u64) local_nasid,
+			(u64) local_widget, __pa(sn_irq_info),
+			(u64) req_nasid, (u64) req_slice, 0);
+
+	return ret_stuff.status;
+}
+
+static unsigned int sn_startup_irq(struct irq_data *data)
 {
 	return 0;
 }
 
-static void sn_shutdown_irq(unsigned int irq)
+static void sn_shutdown_irq(struct irq_data *data)
 {
 }
 
-static void sn_disable_irq(unsigned int irq)
+extern void ia64_mca_register_cpev(int);
+
+static void sn_disable_irq(struct irq_data *data)
 {
+	if (data->irq == local_vector_to_irq(IA64_CPE_VECTOR))
+		ia64_mca_register_cpev(0);
 }
 
-static void sn_enable_irq(unsigned int irq)
+static void sn_enable_irq(struct irq_data *data)
 {
+	if (data->irq == local_vector_to_irq(IA64_CPE_VECTOR))
+		ia64_mca_register_cpev(data->irq);
 }
 
-static void sn_ack_irq(unsigned int irq)
+static void sn_ack_irq(struct irq_data *data)
 {
-	uint64_t event_occurred, mask = 0;
-	int nasid;
+	u64 event_occurred, mask;
+	unsigned int irq = data->irq & 0xff;
 
-	irq = irq & 0xff;
-	nasid = get_nasid();
-	event_occurred =
-	    HUB_L((uint64_t *) GLOBAL_MMR_ADDR(nasid, SH_EVENT_OCCURRED));
+	event_occurred = HUB_L((u64*)LOCAL_MMR_ADDR(SH_EVENT_OCCURRED));
 	mask = event_occurred & SH_ALL_INT_MASK;
-	HUB_S((uint64_t *) GLOBAL_MMR_ADDR(nasid, SH_EVENT_OCCURRED_ALIAS),
-		 mask);
+	HUB_S((u64*)LOCAL_MMR_ADDR(SH_EVENT_OCCURRED_ALIAS), mask);
 	__set_bit(irq, (volatile void *)pda->sn_in_service_ivecs);
 
-	move_irq(irq);
+	irq_move_irq(data);
 }
 
-static void sn_end_irq(unsigned int irq)
+struct sn_irq_info *sn_retarget_vector(struct sn_irq_info *sn_irq_info,
+				       nasid_t nasid, int slice)
 {
-	int nasid;
-	int ivec;
-	uint64_t event_occurred;
-
-	ivec = irq & 0xff;
-	if (ivec == SGI_UART_VECTOR) {
-		nasid = get_nasid();
-		event_occurred = HUB_L((uint64_t *) GLOBAL_MMR_ADDR
-				       (nasid, SH_EVENT_OCCURRED));
-		/* If the UART bit is set here, we may have received an 
-		 * interrupt from the UART that the driver missed.  To
-		 * make sure, we IPI ourselves to force us to look again.
-		 */
-		if (event_occurred & SH_EVENT_OCCURRED_UART_INT_MASK) {
-			platform_send_ipi(smp_processor_id(), SGI_UART_VECTOR,
-					  IA64_IPI_DM_INT, 0);
-		}
+	int vector;
+	int cpuid;
+#ifdef CONFIG_SMP
+	int cpuphys;
+#endif
+	int64_t bridge;
+	int local_widget, status;
+	nasid_t local_nasid;
+	struct sn_irq_info *new_irq_info;
+	struct sn_pcibus_provider *pci_provider;
+
+	bridge = (u64) sn_irq_info->irq_bridge;
+	if (!bridge) {
+		return NULL; /* irq is not a device interrupt */
+	}
+
+	local_nasid = NASID_GET(bridge);
+
+	if (local_nasid & 1)
+		local_widget = TIO_SWIN_WIDGETNUM(bridge);
+	else
+		local_widget = SWIN_WIDGETNUM(bridge);
+	vector = sn_irq_info->irq_irq;
+
+	/* Make use of SAL_INTR_REDIRECT if PROM supports it */
+	status = sn_intr_redirect(local_nasid, local_widget, sn_irq_info, nasid, slice);
+	if (!status) {
+		new_irq_info = sn_irq_info;
+		goto finish_up;
+	}
+
+	/*
+	 * PROM does not support SAL_INTR_REDIRECT, or it failed.
+	 * Revert to old method.
+	 */
+	new_irq_info = kmemdup(sn_irq_info, sizeof(struct sn_irq_info),
+			       GFP_ATOMIC);
+	if (new_irq_info == NULL)
+		return NULL;
+
+	/* Free the old PROM new_irq_info structure */
+	sn_intr_free(local_nasid, local_widget, new_irq_info);
+	unregister_intr_pda(new_irq_info);
+
+	/* allocate a new PROM new_irq_info struct */
+	status = sn_intr_alloc(local_nasid, local_widget,
+			       new_irq_info, vector,
+			       nasid, slice);
+
+	/* SAL call failed */
+	if (status) {
+		kfree(new_irq_info);
+		return NULL;
 	}
-	__clear_bit(ivec, (volatile void *)pda->sn_in_service_ivecs);
-	if (sn_force_interrupt_flag)
-		force_interrupt(irq);
+
+	register_intr_pda(new_irq_info);
+	spin_lock(&sn_irq_info_lock);
+	list_replace_rcu(&sn_irq_info->list, &new_irq_info->list);
+	spin_unlock(&sn_irq_info_lock);
+	kfree_rcu(sn_irq_info, rcu);
+
+
+finish_up:
+	/* Update kernels new_irq_info with new target info */
+	cpuid = nasid_slice_to_cpuid(new_irq_info->irq_nasid,
+				     new_irq_info->irq_slice);
+	new_irq_info->irq_cpuid = cpuid;
+
+	pci_provider = sn_pci_provider[new_irq_info->irq_bridge_type];
+
+	/*
+	 * If this represents a line interrupt, target it.  If it's
+	 * an msi (irq_int_bit < 0), it's already targeted.
+	 */
+	if (new_irq_info->irq_int_bit >= 0 &&
+	    pci_provider && pci_provider->target_interrupt)
+		(pci_provider->target_interrupt)(new_irq_info);
+
+#ifdef CONFIG_SMP
+	cpuphys = cpu_physical_id(cpuid);
+	set_irq_affinity_info((vector & 0xff), cpuphys, 0);
+#endif
+
+	return new_irq_info;
 }
 
-static void sn_set_affinity_irq(unsigned int irq, cpumask_t mask)
+static int sn_set_affinity_irq(struct irq_data *data,
+			       const struct cpumask *mask, bool force)
 {
-	struct sn_irq_info *sn_irq_info = sn_irq[irq];
-	struct sn_irq_info *tmp_sn_irq_info;
-	int cpuid, cpuphys;
-	nasid_t t_nasid;	/* nasid to target */
-	int t_slice;		/* slice to target */
-
-	/* allocate a temp sn_irq_info struct to get new target info */
-	tmp_sn_irq_info = kmalloc(sizeof(*tmp_sn_irq_info), GFP_KERNEL);
-	if (!tmp_sn_irq_info)
-		return;
+	struct sn_irq_info *sn_irq_info, *sn_irq_info_safe;
+	unsigned int irq = data->irq;
+	nasid_t nasid;
+	int slice;
 
-	cpuid = first_cpu(mask);
-	cpuphys = cpu_physical_id(cpuid);
-	t_nasid = cpuid_to_nasid(cpuid);
-	t_slice = cpuid_to_slice(cpuid);
-
-	while (sn_irq_info) {
-		int status;
-		int local_widget;
-		uint64_t bridge = (uint64_t) sn_irq_info->irq_bridge;
-		nasid_t local_nasid = NASID_GET(bridge);
-
-		if (!bridge)
-			break;	/* irq is not a device interrupt */
-
-		if (local_nasid & 1)
-			local_widget = TIO_SWIN_WIDGETNUM(bridge);
-		else
-			local_widget = SWIN_WIDGETNUM(bridge);
-
-		/* Free the old PROM sn_irq_info structure */
-		sn_intr_free(local_nasid, local_widget, sn_irq_info);
-
-		/* allocate a new PROM sn_irq_info struct */
-		status = sn_intr_alloc(local_nasid, local_widget,
-				       __pa(tmp_sn_irq_info), irq, t_nasid,
-				       t_slice);
-
-		if (status == 0) {
-			/* Update kernels sn_irq_info with new target info */
-			unregister_intr_pda(sn_irq_info);
-			sn_irq_info->irq_cpuid = cpuid;
-			sn_irq_info->irq_nasid = t_nasid;
-			sn_irq_info->irq_slice = t_slice;
-			sn_irq_info->irq_xtalkaddr =
-			    tmp_sn_irq_info->irq_xtalkaddr;
-			sn_irq_info->irq_cookie = tmp_sn_irq_info->irq_cookie;
-			register_intr_pda(sn_irq_info);
-
-			if (IS_PCI_BRIDGE_ASIC(sn_irq_info->irq_bridge_type)) {
-				pcibr_change_devices_irq(sn_irq_info);
-			}
+	nasid = cpuid_to_nasid(cpumask_first_and(mask, cpu_online_mask));
+	slice = cpuid_to_slice(cpumask_first_and(mask, cpu_online_mask));
 
-			sn_irq_info = sn_irq_info->irq_next;
+	list_for_each_entry_safe(sn_irq_info, sn_irq_info_safe,
+				 sn_irq_lh[irq], list)
+		(void)sn_retarget_vector(sn_irq_info, nasid, slice);
+
+	return 0;
+}
 
 #ifdef CONFIG_SMP
-			set_irq_affinity_info((irq & 0xff), cpuphys, 0);
+void sn_set_err_irq_affinity(unsigned int irq)
+{
+        /*
+         * On systems which support CPU disabling (SHub2), all error interrupts
+         * are targeted at the boot CPU.
+         */
+        if (is_shub2() && sn_prom_feature_available(PRF_CPU_DISABLE_SUPPORT))
+                set_irq_affinity_info(irq, cpu_physical_id(0), 0);
+}
+#else
+void sn_set_err_irq_affinity(unsigned int irq) { }
 #endif
-		} else {
-			break;	/* snp_affinity failed the intr_alloc */
-		}
-	}
-	kfree(tmp_sn_irq_info);
+
+static void
+sn_mask_irq(struct irq_data *data)
+{
+}
+
+static void
+sn_unmask_irq(struct irq_data *data)
+{
 }
 
-struct hw_interrupt_type irq_type_sn = {
-	"SN hub",
-	sn_startup_irq,
-	sn_shutdown_irq,
-	sn_enable_irq,
-	sn_disable_irq,
-	sn_ack_irq,
-	sn_end_irq,
-	sn_set_affinity_irq
+struct irq_chip irq_type_sn = {
+	.name			= "SN hub",
+	.irq_startup		= sn_startup_irq,
+	.irq_shutdown		= sn_shutdown_irq,
+	.irq_enable		= sn_enable_irq,
+	.irq_disable		= sn_disable_irq,
+	.irq_ack		= sn_ack_irq,
+	.irq_mask		= sn_mask_irq,
+	.irq_unmask		= sn_unmask_irq,
+	.irq_set_affinity	= sn_set_affinity_irq
 };
 
+ia64_vector sn_irq_to_vector(int irq)
+{
+	if (irq >= IA64_NUM_VECTORS)
+		return 0;
+	return (ia64_vector)irq;
+}
+
 unsigned int sn_local_vector_to_irq(u8 vector)
 {
 	return (CPU_VECTOR_TO_IRQ(smp_processor_id(), vector));
@@ -201,12 +270,13 @@ unsigned int sn_local_vector_to_irq(u8 vector)
 void sn_irq_init(void)
 {
 	int i;
-	irq_desc_t *base_desc = irq_desc;
+
+	ia64_first_device_vector = IA64_SN2_FIRST_DEVICE_VECTOR;
+	ia64_last_device_vector = IA64_SN2_LAST_DEVICE_VECTOR;
 
 	for (i = 0; i < NR_IRQS; i++) {
-		if (base_desc[i].handler == &no_irq_type) {
-			base_desc[i].handler = &irq_type_sn;
-		}
+		if (irq_get_chip(i) == &no_irq_chip)
+			irq_set_chip(i, &irq_type_sn);
 	}
 }
 
@@ -219,9 +289,8 @@ static void register_intr_pda(struct sn_irq_info *sn_irq_info)
 		pdacpu(cpu)->sn_last_irq = irq;
 	}
 
-	if (pdacpu(cpu)->sn_first_irq == 0 || pdacpu(cpu)->sn_first_irq > irq) {
+	if (pdacpu(cpu)->sn_first_irq == 0 || pdacpu(cpu)->sn_first_irq > irq)
 		pdacpu(cpu)->sn_first_irq = irq;
-	}
 }
 
 static void unregister_intr_pda(struct sn_irq_info *sn_irq_info)
@@ -231,19 +300,18 @@ static void unregister_intr_pda(struct sn_irq_info *sn_irq_info)
 	struct sn_irq_info *tmp_irq_info;
 	int i, foundmatch;
 
+	rcu_read_lock();
 	if (pdacpu(cpu)->sn_last_irq == irq) {
 		foundmatch = 0;
-		for (i = pdacpu(cpu)->sn_last_irq - 1; i; i--) {
-			tmp_irq_info = sn_irq[i];
-			while (tmp_irq_info) {
+		for (i = pdacpu(cpu)->sn_last_irq - 1;
+		     i && !foundmatch; i--) {
+			list_for_each_entry_rcu(tmp_irq_info,
+						sn_irq_lh[i],
+						list) {
 				if (tmp_irq_info->irq_cpuid == cpu) {
-					foundmatch++;
+					foundmatch = 1;
 					break;
 				}
-				tmp_irq_info = tmp_irq_info->irq_next;
-			}
-			if (foundmatch) {
-				break;
 			}
 		}
 		pdacpu(cpu)->sn_last_irq = i;
@@ -251,61 +319,20 @@ static void unregister_intr_pda(struct sn_irq_info *sn_irq_info)
 
 	if (pdacpu(cpu)->sn_first_irq == irq) {
 		foundmatch = 0;
-		for (i = pdacpu(cpu)->sn_first_irq + 1; i < NR_IRQS; i++) {
-			tmp_irq_info = sn_irq[i];
-			while (tmp_irq_info) {
+		for (i = pdacpu(cpu)->sn_first_irq + 1;
+		     i < NR_IRQS && !foundmatch; i++) {
+			list_for_each_entry_rcu(tmp_irq_info,
+						sn_irq_lh[i],
+						list) {
 				if (tmp_irq_info->irq_cpuid == cpu) {
-					foundmatch++;
+					foundmatch = 1;
 					break;
 				}
-				tmp_irq_info = tmp_irq_info->irq_next;
-			}
-			if (foundmatch) {
-				break;
 			}
 		}
 		pdacpu(cpu)->sn_first_irq = ((i == NR_IRQS) ? 0 : i);
 	}
-}
-
-struct sn_irq_info *sn_irq_alloc(nasid_t local_nasid, int local_widget, int irq,
-				 nasid_t nasid, int slice)
-{
-	struct sn_irq_info *sn_irq_info;
-	int status;
-
-	sn_irq_info = kmalloc(sizeof(*sn_irq_info), GFP_KERNEL);
-	if (sn_irq_info == NULL)
-		return NULL;
-
-	memset(sn_irq_info, 0x0, sizeof(*sn_irq_info));
-
-	status =
-	    sn_intr_alloc(local_nasid, local_widget, __pa(sn_irq_info), irq,
-			  nasid, slice);
-
-	if (status) {
-		kfree(sn_irq_info);
-		return NULL;
-	} else {
-		return sn_irq_info;
-	}
-}
-
-void sn_irq_free(struct sn_irq_info *sn_irq_info)
-{
-	uint64_t bridge = (uint64_t) sn_irq_info->irq_bridge;
-	nasid_t local_nasid = NASID_GET(bridge);
-	int local_widget;
-
-	if (local_nasid & 1)	/* tio check */
-		local_widget = TIO_SWIN_WIDGETNUM(bridge);
-	else
-		local_widget = SWIN_WIDGETNUM(bridge);
-
-	sn_intr_free(local_nasid, local_widget, sn_irq_info);
-
-	kfree(sn_irq_info);
+	rcu_read_unlock();
 }
 
 void sn_irq_fixup(struct pci_dev *pci_dev, struct sn_irq_info *sn_irq_info)
@@ -313,31 +340,72 @@ void sn_irq_fixup(struct pci_dev *pci_dev, struct sn_irq_info *sn_irq_info)
 	nasid_t nasid = sn_irq_info->irq_nasid;
 	int slice = sn_irq_info->irq_slice;
 	int cpu = nasid_slice_to_cpuid(nasid, slice);
+#ifdef CONFIG_SMP
+	int cpuphys;
+#endif
 
+	pci_dev_get(pci_dev);
 	sn_irq_info->irq_cpuid = cpu;
 	sn_irq_info->irq_pciioinfo = SN_PCIDEV_INFO(pci_dev);
 
 	/* link it into the sn_irq[irq] list */
-	sn_irq_info->irq_next = sn_irq[sn_irq_info->irq_irq];
-	sn_irq[sn_irq_info->irq_irq] = sn_irq_info;
-
-	(void)register_intr_pda(sn_irq_info);
+	spin_lock(&sn_irq_info_lock);
+	list_add_rcu(&sn_irq_info->list, sn_irq_lh[sn_irq_info->irq_irq]);
+	reserve_irq_vector(sn_irq_info->irq_irq);
+	if (sn_irq_info->irq_int_bit != -1)
+		irq_set_handler(sn_irq_info->irq_irq, handle_level_irq);
+	spin_unlock(&sn_irq_info_lock);
+
+	register_intr_pda(sn_irq_info);
+#ifdef CONFIG_SMP
+	cpuphys = cpu_physical_id(cpu);
+	set_irq_affinity_info(sn_irq_info->irq_irq, cpuphys, 0);
+	/*
+	 * Affinity was set by the PROM, prevent it from
+	 * being reset by the request_irq() path.
+	 */
+	irqd_mark_affinity_was_set(irq_get_irq_data(sn_irq_info->irq_irq));
+#endif
 }
 
-static void force_interrupt(int irq)
+void sn_irq_unfixup(struct pci_dev *pci_dev)
 {
 	struct sn_irq_info *sn_irq_info;
 
-	if (!sn_ioif_inited)
+	/* Only cleanup IRQ stuff if this device has a host bus context */
+	if (!SN_PCIDEV_BUSSOFT(pci_dev))
+		return;
+
+	sn_irq_info = SN_PCIDEV_INFO(pci_dev)->pdi_sn_irq_info;
+	if (!sn_irq_info)
+		return;
+	if (!sn_irq_info->irq_irq) {
+		kfree(sn_irq_info);
 		return;
-	sn_irq_info = sn_irq[irq];
-	while (sn_irq_info) {
-		if (IS_PCI_BRIDGE_ASIC(sn_irq_info->irq_bridge_type) &&
-		    (sn_irq_info->irq_bridge != NULL)) {
-			pcibr_force_interrupt(sn_irq_info);
-		}
-		sn_irq_info = sn_irq_info->irq_next;
 	}
+
+	unregister_intr_pda(sn_irq_info);
+	spin_lock(&sn_irq_info_lock);
+	list_del_rcu(&sn_irq_info->list);
+	spin_unlock(&sn_irq_info_lock);
+	if (list_empty(sn_irq_lh[sn_irq_info->irq_irq]))
+		free_irq_vector(sn_irq_info->irq_irq);
+	kfree_rcu(sn_irq_info, rcu);
+	pci_dev_put(pci_dev);
+
+}
+
+static inline void
+sn_call_force_intr_provider(struct sn_irq_info *sn_irq_info)
+{
+	struct sn_pcibus_provider *pci_provider;
+
+	pci_provider = sn_pci_provider[sn_irq_info->irq_bridge_type];
+
+	/* Don't force an interrupt if the irq has been disabled */
+	if (!irqd_irq_disabled(irq_get_irq_data(sn_irq_info->irq_irq)) &&
+	    pci_provider && pci_provider->force_interrupt)
+		(*pci_provider->force_interrupt)(sn_irq_info);
 }
 
 /*
@@ -351,13 +419,18 @@ static void force_interrupt(int irq)
  */
 static void sn_check_intr(int irq, struct sn_irq_info *sn_irq_info)
 {
-	uint64_t regval;
-	int irr_reg_num;
-	int irr_bit;
-	uint64_t irr_reg;
+	u64 regval;
 	struct pcidev_info *pcidev_info;
 	struct pcibus_info *pcibus_info;
 
+	/*
+	 * Bridge types attached to TIO (anything but PIC) do not need this WAR
+	 * since they do not target Shub II interrupt registers.  If that
+	 * ever changes, this check needs to accommodate.
+	 */
+	if (sn_irq_info->irq_bridge_type != PCIIO_ASIC_TYPE_PIC)
+		return;
+
 	pcidev_info = (struct pcidev_info *)sn_irq_info->irq_pciioinfo;
 	if (!pcidev_info)
 		return;
@@ -367,33 +440,13 @@ static void sn_check_intr(int irq, struct sn_irq_info *sn_irq_info)
 	    pdi_pcibus_info;
 	regval = pcireg_intr_status_get(pcibus_info);
 
-	irr_reg_num = irq_to_vector(irq) / 64;
-	irr_bit = irq_to_vector(irq) % 64;
-	switch (irr_reg_num) {
-	case 0:
-		irr_reg = ia64_getreg(_IA64_REG_CR_IRR0);
-		break;
-	case 1:
-		irr_reg = ia64_getreg(_IA64_REG_CR_IRR1);
-		break;
-	case 2:
-		irr_reg = ia64_getreg(_IA64_REG_CR_IRR2);
-		break;
-	case 3:
-		irr_reg = ia64_getreg(_IA64_REG_CR_IRR3);
-		break;
-	}
-	if (!test_bit(irr_bit, &irr_reg)) {
-		if (!test_bit(irq, pda->sn_soft_irr)) {
-			if (!test_bit(irq, pda->sn_in_service_ivecs)) {
-				regval &= 0xff;
-				if (sn_irq_info->irq_int_bit & regval &
-				    sn_irq_info->irq_last_intr) {
-					regval &=
-					    ~(sn_irq_info->
-					      irq_int_bit & regval);
-					pcibr_force_interrupt(sn_irq_info);
-				}
+	if (!ia64_get_irr(irq_to_vector(irq))) {
+		if (!test_bit(irq, pda->sn_in_service_ivecs)) {
+			regval &= 0xff;
+			if (sn_irq_info->irq_int_bit & regval &
+			    sn_irq_info->irq_last_intr) {
+				regval &= ~(sn_irq_info->irq_int_bit & regval);
+				sn_call_force_intr_provider(sn_irq_info);
 			}
 		}
 	}
@@ -402,19 +455,34 @@ static void sn_check_intr(int irq, struct sn_irq_info *sn_irq_info)
 
 void sn_lb_int_war_check(void)
 {
+	struct sn_irq_info *sn_irq_info;
 	int i;
 
 	if (!sn_ioif_inited || pda->sn_first_irq == 0)
 		return;
+
+	rcu_read_lock();
 	for (i = pda->sn_first_irq; i <= pda->sn_last_irq; i++) {
-		struct sn_irq_info *sn_irq_info = sn_irq[i];
-		while (sn_irq_info) {
-			/* Only call for PCI bridges that are fully initialized. */
-			if (IS_PCI_BRIDGE_ASIC(sn_irq_info->irq_bridge_type) &&
-			    (sn_irq_info->irq_bridge != NULL)) {
-				sn_check_intr(i, sn_irq_info);
-			}
-			sn_irq_info = sn_irq_info->irq_next;
+		list_for_each_entry_rcu(sn_irq_info, sn_irq_lh[i], list) {
+			sn_check_intr(i, sn_irq_info);
 		}
 	}
+	rcu_read_unlock();
+}
+
+void __init sn_irq_lh_init(void)
+{
+	int i;
+
+	sn_irq_lh = kmalloc(sizeof(struct list_head *) * NR_IRQS, GFP_KERNEL);
+	if (!sn_irq_lh)
+		panic("SN PCI INIT: Failed to allocate memory for PCI init\n");
+
+	for (i = 0; i < NR_IRQS; i++) {
+		sn_irq_lh[i] = kmalloc(sizeof(struct list_head), GFP_KERNEL);
+		if (!sn_irq_lh[i])
+			panic("SN PCI INIT: Failed IRQ memory allocation\n");
+
+		INIT_LIST_HEAD(sn_irq_lh[i]);
+	}
 }