1 files changed, 164 insertions, 0 deletions
diff --git a/arch/mips/kernel/irq.c b/arch/mips/kernel/irq.c
new file mode 100644
index 00000000..a5aa43d0
--- /dev/null
+++ b/arch/mips/kernel/irq.c
@@ -0,0 +1,164 @@
+/*
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License.  See the file "COPYING" in the main directory of this archive
+ * for more details.
+ *
+ * Code to handle x86 style IRQs plus some generic interrupt stuff.
+ *
+ * Copyright (C) 1992 Linus Torvalds
+ * Copyright (C) 1994 - 2000 Ralf Baechle
+ */
+#include <linux/kernel.h>
+#include <linux/delay.h>
+#include <linux/init.h>
+#include <linux/interrupt.h>
+#include <linux/kernel_stat.h>
+#include <linux/proc_fs.h>
+#include <linux/mm.h>
+#include <linux/random.h>
+#include <linux/sched.h>
+#include <linux/seq_file.h>
+#include <linux/kallsyms.h>
+#include <linux/kgdb.h>
+#include <linux/ftrace.h>
+
+#include <linux/atomic.h>
+#include <asm/uaccess.h>
+
+#ifdef CONFIG_KGDB
+int kgdb_early_setup;
+#endif
+
+static unsigned long irq_map[NR_IRQS / BITS_PER_LONG];
+
+int allocate_irqno(void)
+{
+	int irq;
+
+again:
+	irq = find_first_zero_bit(irq_map, NR_IRQS);
+
+	if (irq >= NR_IRQS)
+		return -ENOSPC;
+
+	if (test_and_set_bit(irq, irq_map))
+		goto again;
+
+	return irq;
+}
+
+/*
+ * Allocate the 16 legacy interrupts for i8259 devices.  This happens early
+ * in the kernel initialization so treating allocation failure as BUG() is
+ * ok.
+ */
+void __init alloc_legacy_irqno(void)
+{
+	int i;
+
+	for (i = 0; i <= 16; i++)
+		BUG_ON(test_and_set_bit(i, irq_map));
+}
+
+void free_irqno(unsigned int irq)
+{
+	smp_mb__before_clear_bit();
+	clear_bit(irq, irq_map);
+	smp_mb__after_clear_bit();
+}
+
+/*
+ * '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)
+{
+	smtc_im_ack_irq(irq);
+	printk("unexpected IRQ # %d\n", irq);
+}
+
+atomic_t irq_err_count;
+
+int arch_show_interrupts(struct seq_file *p, int prec)
+{
+	seq_printf(p, "%*s: %10u\n", prec, "ERR", atomic_read(&irq_err_count));
+	return 0;
+}
+
+asmlinkage void spurious_interrupt(void)
+{
+	atomic_inc(&irq_err_count);
+}
+
+void __init init_IRQ(void)
+{
+	int i;
+
+#ifdef CONFIG_KGDB
+	if (kgdb_early_setup)
+		return;
+#endif
+
+	for (i = 0; i < NR_IRQS; i++)
+		irq_set_noprobe(i);
+
+	arch_init_irq();
+
+#ifdef CONFIG_KGDB
+	if (!kgdb_early_setup)
+		kgdb_early_setup = 1;
+#endif
+}
+
+#ifdef DEBUG_STACKOVERFLOW
+static inline void check_stack_overflow(void)
+{
+	unsigned long sp;
+
+	__asm__ __volatile__("move %0, $sp" : "=r" (sp));
+	sp &= THREAD_MASK;
+
+	/*
+	 * Check for stack overflow: is there less than STACK_WARN free?
+	 * STACK_WARN is defined as 1/8 of THREAD_SIZE by default.
+	 */
+	if (unlikely(sp < (sizeof(struct thread_info) + STACK_WARN))) {
+		printk("do_IRQ: stack overflow: %ld\n",
+		       sp - sizeof(struct thread_info));
+		dump_stack();
+	}
+}
+#else
+static inline void check_stack_overflow(void) {}
+#endif
+
+
+/*
+ * do_IRQ handles all normal device IRQ's (the special
+ * SMP cross-CPU interrupts have their own specific
+ * handlers).
+ */
+void __irq_entry do_IRQ(unsigned int irq)
+{
+	irq_enter();
+	check_stack_overflow();
+	if (!smtc_handle_on_other_cpu(irq))
+		generic_handle_irq(irq);
+	irq_exit();
+}
+
+#ifdef CONFIG_MIPS_MT_SMTC_IRQAFF
+/*
+ * To avoid inefficient and in some cases pathological re-checking of
+ * IRQ affinity, we have this variant that skips the affinity check.
+ */
+
+void __irq_entry do_IRQ_no_affinity(unsigned int irq)
+{
+	irq_enter();
+	smtc_im_backstop(irq);
+	generic_handle_irq(irq);
+	irq_exit();
+}
+
+#endif /* CONFIG_MIPS_MT_SMTC_IRQAFF */