intr.c

TI OMAP 1510上mcbsp的驱动程序

/******************************************************************/
/* intr.c V0.00                                                   */
/* Copyright (c) Texas Instruments , Incorporated  1997           */
/******************************************************************/
/******************************************************************/
/* Define temp location for storing interrupt vector locations    */
/******************************************************************/
#include <intr.h>

extern interrupt void _intr_handler();
extern int _vectors;	 //Start label of vector table

void hook_interrupt(unsigned int trap, Ip func)
{
	unsigned long _branch = 0x6a00ul;
	unsigned long _func = (unsigned long)func;
	unsigned long *_addr = (unsigned long *)(((unsigned long)&_vectors + (trap * 0x8)) >> 1);

	*_addr = (_branch << 16) | _func;
}

void unhook_interrupt(unsigned int trap)
{
	unsigned long _branch = 0x6a00ul;
	unsigned long _func = (unsigned long)_intr_handler;
	unsigned long *_addr = (unsigned long *)(((unsigned long)&_vectors + (trap * 0x8)) >> 1);

	*_addr = (_branch << 16) | _func;
}