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-rw-r--r--arch/alpha/kernel/irq.c122
1 files changed, 122 insertions, 0 deletions
diff --git a/arch/alpha/kernel/irq.c b/arch/alpha/kernel/irq.c
new file mode 100644
index 000000000..51f2c8654
--- /dev/null
+++ b/arch/alpha/kernel/irq.c
@@ -0,0 +1,122 @@
+/*
+ * linux/arch/alpha/kernel/irq.c
+ *
+ * Copyright (C) 1995 Linus Torvalds
+ *
+ * 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.
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/errno.h>
+#include <linux/kernel_stat.h>
+#include <linux/signal.h>
+#include <linux/sched.h>
+#include <linux/ptrace.h>
+#include <linux/interrupt.h>
+#include <linux/random.h>
+#include <linux/irq.h>
+#include <linux/proc_fs.h>
+#include <linux/seq_file.h>
+#include <linux/profile.h>
+#include <linux/bitops.h>
+
+#include <asm/io.h>
+#include <asm/uaccess.h>
+
+volatile unsigned long irq_err_count;
+DEFINE_PER_CPU(unsigned long, irq_pmi_count);
+
+void ack_bad_irq(unsigned int irq)
+{
+ irq_err_count++;
+ printk(KERN_CRIT "Unexpected IRQ trap at vector %u\n", irq);
+}
+
+#ifdef CONFIG_SMP
+static char irq_user_affinity[NR_IRQS];
+
+int irq_select_affinity(unsigned int irq)
+{
+ struct irq_data *data = irq_get_irq_data(irq);
+ struct irq_chip *chip;
+ static int last_cpu;
+ int cpu = last_cpu + 1;
+
+ if (!data)
+ return 1;
+ chip = irq_data_get_irq_chip(data);
+
+ if (!chip->irq_set_affinity || irq_user_affinity[irq])
+ return 1;
+
+ while (!cpu_possible(cpu) ||
+ !cpumask_test_cpu(cpu, irq_default_affinity))
+ cpu = (cpu < (NR_CPUS-1) ? cpu + 1 : 0);
+ last_cpu = cpu;
+
+ cpumask_copy(data->affinity, cpumask_of(cpu));
+ chip->irq_set_affinity(data, cpumask_of(cpu), false);
+ return 0;
+}
+#endif /* CONFIG_SMP */
+
+int arch_show_interrupts(struct seq_file *p, int prec)
+{
+ int j;
+
+#ifdef CONFIG_SMP
+ seq_puts(p, "IPI: ");
+ for_each_online_cpu(j)
+ seq_printf(p, "%10lu ", cpu_data[j].ipi_count);
+ seq_putc(p, '\n');
+#endif
+ seq_puts(p, "PMI: ");
+ for_each_online_cpu(j)
+ seq_printf(p, "%10lu ", per_cpu(irq_pmi_count, j));
+ seq_puts(p, " Performance Monitoring\n");
+ seq_printf(p, "ERR: %10lu\n", irq_err_count);
+ return 0;
+}
+
+/*
+ * handle_irq handles all normal device IRQ's (the special
+ * SMP cross-CPU interrupts have their own specific
+ * handlers).
+ */
+
+#define MAX_ILLEGAL_IRQS 16
+
+void
+handle_irq(int irq)
+{
+ /*
+ * We ack quickly, we don't want the irq controller
+ * thinking we're snobs just because some other CPU has
+ * disabled global interrupts (we have already done the
+ * INT_ACK cycles, it's too late to try to pretend to the
+ * controller that we aren't taking the interrupt).
+ *
+ * 0 return value means that this irq is already being
+ * handled by some other CPU. (or is disabled)
+ */
+ static unsigned int illegal_count=0;
+ struct irq_desc *desc = irq_to_desc(irq);
+
+ if (!desc || ((unsigned) irq > ACTUAL_NR_IRQS &&
+ illegal_count < MAX_ILLEGAL_IRQS)) {
+ irq_err_count++;
+ illegal_count++;
+ printk(KERN_CRIT "device_interrupt: invalid interrupt %d\n",
+ irq);
+ return;
+ }
+
+ irq_enter();
+ generic_handle_irq_desc(irq, desc);
+ irq_exit();
+}