void timer_cycle(void)
{
/* The amount of ticks since we last ran */
unsigned int delta = cpu_get_cycles() - prev_time;
prev_time = cpu_get_cycles();
elapsed += delta * 4; /* 4 cycles to a timer tick */
if(elapsed >= 16)
{
timer_tick();
elapsed -= 16; /* keep track of the time overflow */
}
}
//Recup donnée immédiate de 16 bits
unsigned short mem_get_word(unsigned short i){
unsigned long elapsed;
if(DMA_pending && i < 0xFF80)
{
elapsed = cpu_get_cycles() - DMA_pending;
if(elapsed >= 160)
DMA_pending = 0;
else
{
return mem[0xFE00+elapsed];
}
}
return mem[i] | (mem[i+1]<<8);
}
//Recup donnée immédiate de 8 bits
unsigned char mem_get_byte(unsigned short i)
{
unsigned long elapsed;
unsigned char mask = 0;
if(DMA_pending && i < 0xFF80)
{
elapsed = cpu_get_cycles() - DMA_pending;
if(elapsed >= 160)
DMA_pending = 0;
else
{
return mem[0xFE00+elapsed];
}
}
return mem[i];
}
int sys_clock(uint64_t *val)
{
error_t err;
uint64_t cycles;
if((val == NULL) || NOT_IN_USPACE((uint_t)val))
{
err = EINVAL;
goto fail_inval;
}
cycles = cpu_get_cycles(current_cpu);
err = cpu_copy_to_uspace(val, &cycles, sizeof(cycles));
fail_inval:
current_thread->info.errno = err;
return err;
}
