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 static __inline__
int irq_canonicalize(int irq
)
28 return ((irq
== 2) ? 9 : irq
);
31 extern void disable_irq(unsigned int);
32 extern void disable_irq_nosync(unsigned int);
33 extern void enable_irq(unsigned int);
35 #ifdef CONFIG_X86_LOCAL_APIC
36 #define ARCH_HAS_NMI_WATCHDOG /* See include/linux/nmi.h */
39 #endif /* _ASM_IRQ_H */