nes-proj/drivers/cpu/arm/at91sam7s/interrupt-utils.c

85 lines
1.7 KiB
C

/******************************************************************************
*
* $RCSfile: interrupt-utils.c,v $
* $Revision: 1.2 $
*
* This module provides the interface routines for setting up and
* controlling the various interrupt modes present on the ARM processor.
* Copyright 2004, R O SoftWare
* No guarantees, warrantees, or promises, implied or otherwise.
* May be used for hobby or commercial purposes provided copyright
* notice remains intact.
*
*****************************************************************************/
#include "interrupt-utils.h"
#define IRQ_MASK 0x00000080
#define FIQ_MASK 0x00000040
#define INT_MASK (IRQ_MASK | FIQ_MASK)
static inline unsigned __get_cpsr(void)
{
unsigned long retval;
asm volatile (" mrs %0, cpsr" : "=r" (retval) : /* no inputs */ );
return retval;
}
static inline void __set_cpsr(unsigned val)
{
asm volatile (" msr cpsr_c, %0" : /* no outputs */ : "r" (val) );
}
unsigned disableIRQ(void)
{
unsigned _cpsr;
_cpsr = __get_cpsr();
__set_cpsr(_cpsr | IRQ_MASK);
return _cpsr;
}
unsigned restoreIRQ(unsigned oldCPSR)
{
unsigned _cpsr;
_cpsr = __get_cpsr();
__set_cpsr((_cpsr & ~IRQ_MASK) | (oldCPSR & IRQ_MASK));
return _cpsr;
}
unsigned enableIRQ(void)
{
unsigned _cpsr;
_cpsr = __get_cpsr();
__set_cpsr(_cpsr & ~IRQ_MASK);
return _cpsr;
}
unsigned disableFIQ(void)
{
unsigned _cpsr;
_cpsr = __get_cpsr();
__set_cpsr(_cpsr | FIQ_MASK);
return _cpsr;
}
unsigned restoreFIQ(unsigned oldCPSR)
{
unsigned _cpsr;
_cpsr = __get_cpsr();
__set_cpsr((_cpsr & ~FIQ_MASK) | (oldCPSR & FIQ_MASK));
return _cpsr;
}
unsigned enableFIQ(void)
{
unsigned _cpsr;
_cpsr = __get_cpsr();
__set_cpsr(_cpsr & ~FIQ_MASK);
return _cpsr;
}