1 files changed, 238 insertions, 0 deletions
diff --git a/arch/ia64/kernel/irq.c b/arch/ia64/kernel/irq.c
new file mode 100644
index 00000000000..28f2aadc38d
--- /dev/null
+++ b/arch/ia64/kernel/irq.c
@@ -0,0 +1,238 @@
+/*
+ *	linux/arch/ia64/kernel/irq.c
+ *
+ *	Copyright (C) 1992, 1998 Linus Torvalds, Ingo Molnar
+ *
+ * This file contains the code used by various IRQ handling routines:
+ * asking for different IRQ's should be done through these routines
+ * instead of just grabbing them. Thus setups with different IRQ numbers
+ * shouldn't result in any weird surprises, and installing new handlers
+ * should be easier.
+ *
+ * Copyright (C) Ashok Raj<ashok.raj@intel.com>, Intel Corporation 2004
+ *
+ * 4/14/2004: Added code to handle cpu migration and do safe irq
+ *			migration without lossing interrupts for iosapic
+ *			architecture.
+ */
+
+#include <asm/delay.h>
+#include <asm/uaccess.h>
+#include <linux/module.h>
+#include <linux/seq_file.h>
+#include <linux/interrupt.h>
+#include <linux/kernel_stat.h>
+
+/*
+ * 'what should we do if we get a hw irq event on an illegal vector'.
+ * each architecture has to answer this themselves.
+ */
+void ack_bad_irq(unsigned int irq)
+{
+	printk(KERN_ERR "Unexpected irq vector 0x%x on CPU %u!\n", irq, smp_processor_id());
+}
+
+#ifdef CONFIG_IA64_GENERIC
+unsigned int __ia64_local_vector_to_irq (ia64_vector vec)
+{
+	return (unsigned int) vec;
+}
+#endif
+
+/*
+ * Interrupt statistics:
+ */
+
+atomic_t irq_err_count;
+
+/*
+ * /proc/interrupts printing:
+ */
+
+int show_interrupts(struct seq_file *p, void *v)
+{
+	int i = *(loff_t *) v, j;
+	struct irqaction * action;
+	unsigned long flags;
+
+	if (i == 0) {
+		seq_printf(p, "           ");
+		for (j=0; j<NR_CPUS; j++)
+			if (cpu_online(j))
+				seq_printf(p, "CPU%d       ",j);
+		seq_putc(p, '\n');
+	}
+
+	if (i < NR_IRQS) {
+		spin_lock_irqsave(&irq_desc[i].lock, flags);
+		action = irq_desc[i].action;
+		if (!action)
+			goto skip;
+		seq_printf(p, "%3d: ",i);
+#ifndef CONFIG_SMP
+		seq_printf(p, "%10u ", kstat_irqs(i));
+#else
+		for (j = 0; j < NR_CPUS; j++)
+			if (cpu_online(j))
+				seq_printf(p, "%10u ", kstat_cpu(j).irqs[i]);
+#endif
+		seq_printf(p, " %14s", irq_desc[i].handler->typename);
+		seq_printf(p, "  %s", action->name);
+
+		for (action=action->next; action; action = action->next)
+			seq_printf(p, ", %s", action->name);
+
+		seq_putc(p, '\n');
+skip:
+		spin_unlock_irqrestore(&irq_desc[i].lock, flags);
+	} else if (i == NR_IRQS)
+		seq_printf(p, "ERR: %10u\n", atomic_read(&irq_err_count));
+	return 0;
+}
+
+#ifdef CONFIG_SMP
+/*
+ * This is updated when the user sets irq affinity via /proc
+ */
+static cpumask_t __cacheline_aligned pending_irq_cpumask[NR_IRQS];
+static unsigned long pending_irq_redir[BITS_TO_LONGS(NR_IRQS)];
+
+static char irq_redir [NR_IRQS]; // = { [0 ... NR_IRQS-1] = 1 };
+
+/*
+ * Arch specific routine for deferred write to iosapic rte to reprogram
+ * intr destination.
+ */
+void proc_set_irq_affinity(unsigned int irq, cpumask_t mask_val)
+{
+	pending_irq_cpumask[irq] = mask_val;
+}
+
+void set_irq_affinity_info (unsigned int irq, int hwid, int redir)
+{
+	cpumask_t mask = CPU_MASK_NONE;
+
+	cpu_set(cpu_logical_id(hwid), mask);
+
+	if (irq < NR_IRQS) {
+		irq_affinity[irq] = mask;
+		irq_redir[irq] = (char) (redir & 0xff);
+	}
+}
+
+
+void move_irq(int irq)
+{
+	/* note - we hold desc->lock */
+	cpumask_t tmp;
+	irq_desc_t *desc = irq_descp(irq);
+	int redir = test_bit(irq, pending_irq_redir);
+
+	if (unlikely(!desc->handler->set_affinity))
+		return;
+
+	if (!cpus_empty(pending_irq_cpumask[irq])) {
+		cpus_and(tmp, pending_irq_cpumask[irq], cpu_online_map);
+		if (unlikely(!cpus_empty(tmp))) {
+			desc->handler->set_affinity(irq | (redir ? IA64_IRQ_REDIRECTED : 0),
+						    pending_irq_cpumask[irq]);
+		}
+		cpus_clear(pending_irq_cpumask[irq]);
+	}
+}
+
+
+#endif /* CONFIG_SMP */
+
+#ifdef CONFIG_HOTPLUG_CPU
+unsigned int vectors_in_migration[NR_IRQS];
+
+/*
+ * Since cpu_online_map is already updated, we just need to check for
+ * affinity that has zeros
+ */
+static void migrate_irqs(void)
+{
+	cpumask_t	mask;
+	irq_desc_t *desc;
+	int 		irq, new_cpu;
+
+	for (irq=0; irq < NR_IRQS; irq++) {
+		desc = irq_descp(irq);
+
+		/*
+		 * No handling for now.
+		 * TBD: Implement a disable function so we can now
+		 * tell CPU not to respond to these local intr sources.
+		 * such as ITV,CPEI,MCA etc.
+		 */
+		if (desc->status == IRQ_PER_CPU)
+			continue;
+
+		cpus_and(mask, irq_affinity[irq], cpu_online_map);
+		if (any_online_cpu(mask) == NR_CPUS) {
+			/*
+			 * Save it for phase 2 processing
+			 */
+			vectors_in_migration[irq] = irq;
+
+			new_cpu = any_online_cpu(cpu_online_map);
+			mask = cpumask_of_cpu(new_cpu);
+
+			/*
+			 * Al three are essential, currently WARN_ON.. maybe panic?
+			 */
+			if (desc->handler && desc->handler->disable &&
+				desc->handler->enable && desc->handler->set_affinity) {
+				desc->handler->disable(irq);
+				desc->handler->set_affinity(irq, mask);
+				desc->handler->enable(irq);
+			} else {
+				WARN_ON((!(desc->handler) || !(desc->handler->disable) ||
+						!(desc->handler->enable) ||
+						!(desc->handler->set_affinity)));
+			}
+		}
+	}
+}
+
+void fixup_irqs(void)
+{
+	unsigned int irq;
+	extern void ia64_process_pending_intr(void);
+
+	ia64_set_itv(1<<16);
+	/*
+	 * Phase 1: Locate irq's bound to this cpu and
+	 * relocate them for cpu removal.
+	 */
+	migrate_irqs();
+
+	/*
+	 * Phase 2: Perform interrupt processing for all entries reported in
+	 * local APIC.
+	 */
+	ia64_process_pending_intr();
+
+	/*
+	 * Phase 3: Now handle any interrupts not captured in local APIC.
+	 * This is to account for cases that device interrupted during the time the
+	 * rte was being disabled and re-programmed.
+	 */
+	for (irq=0; irq < NR_IRQS; irq++) {
+		if (vectors_in_migration[irq]) {
+			vectors_in_migration[irq]=0;
+			__do_IRQ(irq, NULL);
+		}
+	}
+
+	/*
+	 * Now let processor die. We do irq disable and max_xtp() to
+	 * ensure there is no more interrupts routed to this processor.
+	 * But the local timer interrupt can have 1 pending which we
+	 * take care in timer_interrupt().
+	 */
+	max_xtp();
+	local_irq_disable();
+}
+#endif