5 * linux/include/asm/irq.h
7 * (C) 1992, 1993 Linus Torvalds, (C) 1997 Ingo Molnar
9 * IRQ/IPI changes taken from work by Thomas Radke
10 * <tomsoft@informatik.tu-chemnitz.de>
16 * 16 8259A IRQ's, 208 potential APIC interrupt sources.
17 * Right now the APIC is mostly only used for SMP.
18 * 256 vectors is an architectural limit. (we can have
19 * more than 256 devices theoretically, but they will
20 * have to use shared interrupts)
21 * Since vectors 0x00-0x1f are used/reserved for the CPU,
22 * the usable vector space is 0x20-0xff (224 vectors)
26 * The maximum number of vectors supported by x86_64 processors
27 * is limited to 256. For processors other than x86_64, NR_VECTORS
28 * should be changed accordingly.
30 #define NR_VECTORS 256
32 #define FIRST_SYSTEM_VECTOR 0xef /* duplicated in hw_irq.h */
35 #define NR_IRQS FIRST_SYSTEM_VECTOR
36 #define NR_IRQ_VECTORS NR_IRQS
39 #define NR_IRQ_VECTORS 1024
42 static __inline__ int irq_canonicalize(int irq)
44 return ((irq == 2) ? 9 : irq);
47 #ifdef CONFIG_X86_LOCAL_APIC
48 #define ARCH_HAS_NMI_WATCHDOG /* See include/linux/nmi.h */
53 int handle_IRQ_event(unsigned int, struct pt_regs *, struct irqaction *);
55 #endif /* _ASM_IRQ_H */