2 * linux/arch/xtensa/kernel/irq.c
4 * Xtensa built-in interrupt controller and some generic functions copied
7 * Copyright (C) 2002 - 2005 Tensilica, Inc.
8 * Copyright (C) 1992, 1998 Linus Torvalds, Ingo Molnar
11 * Chris Zankel <chris@zankel.net>
16 #include <linux/module.h>
17 #include <linux/seq_file.h>
18 #include <linux/interrupt.h>
19 #include <linux/irq.h>
20 #include <linux/kernel_stat.h>
22 #include <asm/uaccess.h>
23 #include <asm/platform.h>
25 static void enable_xtensa_irq(unsigned int irq);
26 static void disable_xtensa_irq(unsigned int irq);
27 static void mask_and_ack_xtensa(unsigned int irq);
28 static void end_xtensa_irq(unsigned int irq);
30 static unsigned int cached_irq_mask;
32 atomic_t irq_err_count;
35 * 'what should we do if we get a hw irq event on an illegal vector'.
36 * each architecture has to answer this themselves.
38 void ack_bad_irq(unsigned int irq)
40 printk("unexpected IRQ trap at vector %02x\n", irq);
44 * do_IRQ handles all normal device IRQ's (the special
45 * SMP cross-CPU interrupts have their own specific
49 unsigned int do_IRQ(int irq, struct pt_regs *regs)
53 #ifdef CONFIG_DEBUG_STACKOVERFLOW
54 /* Debugging check for stack overflow: is there less than 1KB free? */
58 __asm__ __volatile__ ("mov %0, a1\n" : "=a" (sp));
59 sp &= THREAD_SIZE - 1;
61 if (unlikely(sp < (sizeof(thread_info) + 1024)))
62 printk("Stack overflow in do_IRQ: %ld\n",
63 sp - sizeof(struct thread_info));
73 * Generic, controller-independent functions:
76 int show_interrupts(struct seq_file *p, void *v)
78 int i = *(loff_t *) v, j;
79 struct irqaction * action;
84 for_each_online_cpu(j)
85 seq_printf(p, "CPU%d ",j);
90 spin_lock_irqsave(&irq_desc[i].lock, flags);
91 action = irq_desc[i].action;
94 seq_printf(p, "%3d: ",i);
96 seq_printf(p, "%10u ", kstat_irqs(i));
98 for_each_online_cpu(j)
99 seq_printf(p, "%10u ", kstat_cpu(j).irqs[i]);
101 seq_printf(p, " %14s", irq_desc[i].chip->typename);
102 seq_printf(p, " %s", action->name);
104 for (action=action->next; action; action = action->next)
105 seq_printf(p, ", %s", action->name);
109 spin_unlock_irqrestore(&irq_desc[i].lock, flags);
110 } else if (i == NR_IRQS) {
111 seq_printf(p, "NMI: ");
112 for_each_online_cpu(j)
113 seq_printf(p, "%10u ", nmi_count(j));
115 seq_printf(p, "ERR: %10u\n", atomic_read(&irq_err_count));
119 /* shutdown is same as "disable" */
120 #define shutdown_xtensa_irq disable_xtensa_irq
122 static unsigned int startup_xtensa_irq(unsigned int irq)
124 enable_xtensa_irq(irq);
125 return 0; /* never anything pending */
128 static struct hw_interrupt_type xtensa_irq_type = {
138 static inline void mask_irq(unsigned int irq)
140 cached_irq_mask &= ~(1 << irq);
141 set_sr (cached_irq_mask, INTENABLE);
144 static inline void unmask_irq(unsigned int irq)
146 cached_irq_mask |= 1 << irq;
147 set_sr (cached_irq_mask, INTENABLE);
150 static void disable_xtensa_irq(unsigned int irq)
153 local_save_flags(flags);
155 local_irq_restore(flags);
158 static void enable_xtensa_irq(unsigned int irq)
161 local_save_flags(flags);
163 local_irq_restore(flags);
166 static void mask_and_ack_xtensa(unsigned int irq)
168 disable_xtensa_irq(irq);
171 static void end_xtensa_irq(unsigned int irq)
173 enable_xtensa_irq(irq);
177 void __init init_IRQ(void)
181 for (i=0; i < XTENSA_NR_IRQS; i++)
182 irq_desc[i].chip = &xtensa_irq_type;