boop/lpctool/irq.c
2017-07-01 22:09:52 +02:00

43 lines
762 B
C

#include "lpc2220.hh"
#include "irq.h"
#define IRQ_MASK 0x00000080
static inline unsigned asm_get_cpsr(void)
{
unsigned long retval;
asm volatile (" mrs %0, cpsr" : "=r" (retval) : /* no inputs */ );
return retval;
}
static inline void asm_set_cpsr(unsigned val)
{
asm volatile (" msr cpsr, %0" : /* no outputs */ : "r" (val) );
}
unsigned enableIRQ(void)
{
unsigned _cpsr;
_cpsr = asm_get_cpsr();
asm_set_cpsr(_cpsr & ~IRQ_MASK);
return _cpsr;
}
unsigned disableIRQ(void)
{
unsigned _cpsr;
_cpsr = asm_get_cpsr();
asm_set_cpsr(_cpsr | IRQ_MASK);
return _cpsr;
}
unsigned restoreIRQ(unsigned oldCPSR)
{
unsigned _cpsr;
_cpsr = asm_get_cpsr();
asm_set_cpsr((_cpsr & ~IRQ_MASK) | (oldCPSR & IRQ_MASK));
return _cpsr;
}