[PATCH] PCI: altix: msi support

MSI callouts for altix.  Involves a fair amount of code reorg in sn irq.c
code as well as adding some extensions to the altix PCI provider abstaction.

Signed-off-by: Mark Maule <maule@sgi.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

1 files changed, 77 insertions, 58 deletions

diff --git a/arch/ia64/sn/kernel/irq.c b/arch/ia64/sn/kernel/irq.c
index db187f5cdae1..dc8e2b696713 100644
--- a/arch/ia64/sn/kernel/irq.c
+++ b/arch/ia64/sn/kernel/irq.c
@@ -26,11 +26,11 @@ static void unregister_intr_pda(struct sn_irq_info *sn_irq_info);
 
 int sn_force_interrupt_flag = 1;
 extern int sn_ioif_inited;
-static struct list_head **sn_irq_lh;
+struct list_head **sn_irq_lh;
 static spinlock_t sn_irq_info_lock = SPIN_LOCK_UNLOCKED; /* non-IRQ lock */
 
-static inline u64 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)
 {
@@ -40,12 +40,13 @@ static inline u64 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;
@@ -112,73 +113,91 @@ static void sn_end_irq(unsigned int irq)
 
 static void sn_irq_info_free(struct rcu_head *head);
 
-static void sn_set_affinity_irq(unsigned int irq, cpumask_t mask)
+struct sn_irq_info *sn_retarget_vector(struct sn_irq_info *sn_irq_info,
+                                       nasid_t nasid, int slice)
 {
-        struct sn_irq_info *sn_irq_info, *sn_irq_info_safe;
-        int cpuid, cpuphys;
+        int vector;
+        int cpuphys;
+        int64_t bridge;
+        int local_widget, status;
+        nasid_t local_nasid;
+        struct sn_irq_info *new_irq_info;
+        struct sn_pcibus_provider *pci_provider;
 
-        cpuid = first_cpu(mask);
-        cpuphys = cpu_physical_id(cpuid);
+        new_irq_info = kmalloc(sizeof(struct sn_irq_info), GFP_ATOMIC);
+        if (new_irq_info == NULL)
+                return NULL;
 
-        list_for_each_entry_safe(sn_irq_info, sn_irq_info_safe,
-                                 sn_irq_lh[irq], list) {
-                u64 bridge;
-                int local_widget, status;
-                nasid_t local_nasid;
-                struct sn_irq_info *new_irq_info;
-                struct sn_pcibus_provider *pci_provider;
-
-                new_irq_info = kmalloc(sizeof(struct sn_irq_info), GFP_ATOMIC);
-                if (new_irq_info == NULL)
-                        break;
-                memcpy(new_irq_info, sn_irq_info, sizeof(struct sn_irq_info));
-
-                bridge = (u64) new_irq_info->irq_bridge;
-                if (!bridge) {
-                        kfree(new_irq_info);
-                        break; /* irq is not a device interrupt */
-                }
+        memcpy(new_irq_info, sn_irq_info, sizeof(struct sn_irq_info));
 
-                local_nasid = NASID_GET(bridge);
+        bridge = (u64) new_irq_info->irq_bridge;
+        if (!bridge) {
+                kfree(new_irq_info);
+                return NULL; /* irq is not a device interrupt */
+        }
 
-                if (local_nasid & 1)
-                        local_widget = TIO_SWIN_WIDGETNUM(bridge);
-                else
-                        local_widget = SWIN_WIDGETNUM(bridge);
+        local_nasid = NASID_GET(bridge);
 
-                /* Free the old PROM new_irq_info structure */
-                sn_intr_free(local_nasid, local_widget, new_irq_info);
-                /* Update kernels new_irq_info with new target info */
-                unregister_intr_pda(new_irq_info);
+        if (local_nasid & 1)
+                local_widget = TIO_SWIN_WIDGETNUM(bridge);
+        else
+                local_widget = SWIN_WIDGETNUM(bridge);
 
-                /* allocate a new PROM new_irq_info struct */
-                status = sn_intr_alloc(local_nasid, local_widget,
-                                       __pa(new_irq_info), irq,
-                                       cpuid_to_nasid(cpuid),
-                                       cpuid_to_slice(cpuid));
+        vector = sn_irq_info->irq_irq;
+        /* Free the old PROM new_irq_info structure */
+        sn_intr_free(local_nasid, local_widget, new_irq_info);
+        /* Update kernels new_irq_info with new target info */
+        unregister_intr_pda(new_irq_info);
 
-                /* SAL call failed */
-                if (status) {
-                        kfree(new_irq_info);
-                        break;
-                }
+        /* 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;
+        }
 
-                new_irq_info->irq_cpuid = cpuid;
-                register_intr_pda(new_irq_info);
+        cpuphys = nasid_slice_to_cpuid(nasid, slice);
+        new_irq_info->irq_cpuid = cpuphys;
+        register_intr_pda(new_irq_info);
 
-                pci_provider = sn_pci_provider[new_irq_info->irq_bridge_type];
-                if (pci_provider && pci_provider->target_interrupt)
-                        (pci_provider->target_interrupt)(new_irq_info);
+        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);
 
-                spin_lock(&sn_irq_info_lock);
-                list_replace_rcu(&sn_irq_info->list, &new_irq_info->list);
-                spin_unlock(&sn_irq_info_lock);
-                call_rcu(&sn_irq_info->rcu, sn_irq_info_free);
+        spin_lock(&sn_irq_info_lock);
+        list_replace_rcu(&sn_irq_info->list, &new_irq_info->list);
+        spin_unlock(&sn_irq_info_lock);
+        call_rcu(&sn_irq_info->rcu, sn_irq_info_free);
 
 #ifdef CONFIG_SMP
-                set_irq_affinity_info((irq & 0xff), cpuphys, 0);
+        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)
+{
+        struct sn_irq_info *sn_irq_info, *sn_irq_info_safe;
+        nasid_t nasid;
+        int slice;
+
+        nasid = cpuid_to_nasid(first_cpu(mask));
+        slice = cpuid_to_slice(first_cpu(mask));
+
+        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);
 }
 
 struct hw_interrupt_type irq_type_sn = {