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
));
75 * Generic, controller-independent functions:
78 int show_interrupts(struct seq_file
*p
, void *v
)
80 int i
= *(loff_t
*) v
, j
;
81 struct irqaction
* action
;
86 for_each_online_cpu(j
)
87 seq_printf(p
, "CPU%d ",j
);
92 spin_lock_irqsave(&irq_desc
[i
].lock
, flags
);
93 action
= irq_desc
[i
].action
;
96 seq_printf(p
, "%3d: ",i
);
98 seq_printf(p
, "%10u ", kstat_irqs(i
));
100 for_each_online_cpu(j
)
101 seq_printf(p
, "%10u ", kstat_cpu(j
).irqs
[i
]);
103 seq_printf(p
, " %14s", irq_desc
[i
].handler
->typename
);
104 seq_printf(p
, " %s", action
->name
);
106 for (action
=action
->next
; action
; action
= action
->next
)
107 seq_printf(p
, ", %s", action
->name
);
111 spin_unlock_irqrestore(&irq_desc
[i
].lock
, flags
);
112 } else if (i
== NR_IRQS
) {
113 seq_printf(p
, "NMI: ");
114 for_each_online_cpu(j
)
115 seq_printf(p
, "%10u ", nmi_count(j
));
117 seq_printf(p
, "ERR: %10u\n", atomic_read(&irq_err_count
));
121 /* shutdown is same as "disable" */
122 #define shutdown_xtensa_irq disable_xtensa_irq
124 static unsigned int startup_xtensa_irq(unsigned int irq
)
126 enable_xtensa_irq(irq
);
127 return 0; /* never anything pending */
130 static struct hw_interrupt_type xtensa_irq_type
= {
140 static inline void mask_irq(unsigned int irq
)
142 cached_irq_mask
&= ~(1 << irq
);
143 set_sr (cached_irq_mask
, INTENABLE
);
146 static inline void unmask_irq(unsigned int irq
)
148 cached_irq_mask
|= 1 << irq
;
149 set_sr (cached_irq_mask
, INTENABLE
);
152 static void disable_xtensa_irq(unsigned int irq
)
155 local_save_flags(flags
);
157 local_irq_restore(flags
);
160 static void enable_xtensa_irq(unsigned int irq
)
163 local_save_flags(flags
);
165 local_irq_restore(flags
);
168 static void mask_and_ack_xtensa(unsigned int irq
)
170 disable_xtensa_irq(irq
);
173 static void end_xtensa_irq(unsigned int irq
)
175 enable_xtensa_irq(irq
);
179 void __init
init_IRQ(void)
183 for (i
=0; i
< XTENSA_NR_IRQS
; i
++)
184 irq_desc
[i
].handler
= &xtensa_irq_type
;