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-rw-r--r--arch/ia64/kernel/irq.c238
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
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+++ b/arch/ia64/kernel/irq.c
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+/*
+ * 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