int rt_hw_timer_init(void)
{
uint32_t freq;
// Make sure the timer is off.
HW_ARMGLOBALTIMER_CONTROL.B.TIMER_ENABLE = 0;
HW_ARMGLOBALTIMER_CONTROL.B.FCR0 =1;
HW_ARMGLOBALTIMER_CONTROL.B.FCR1 =0;
HW_ARMGLOBALTIMER_CONTROL.B.DBG_ENABLE =0;
// Clear counter.
HW_ARMGLOBALTIMER_COUNTER_HI_WR(0);
HW_ARMGLOBALTIMER_COUNTER_LO_WR(0);
// Now turn on the timer.
HW_ARMGLOBALTIMER_CONTROL.B.TIMER_ENABLE = 1;
freq = get_main_clock(IPG_CLK);
epit_init(HW_EPIT1, CLKSRC_IPG_CLK, freq / 1000000,
SET_AND_FORGET, 10000, WAIT_MODE_EN | STOP_MODE_EN);
epit_counter_enable(HW_EPIT1, 10000, IRQ_MODE);
rt_hw_interrupt_install(IMX_INT_EPIT1, rt_hw_timer_isr, RT_NULL, "tick");
rt_hw_interrupt_umask(IMX_INT_EPIT1);
return 0;
}
int rt_hw_timer_init(void)
{
uint32_t freq;
// The ARM private peripheral clock is half the CPU clock.
uint32_t periphClock = get_main_clock(CPU_CLK) / 2;
uint32_t prescaler = (periphClock / 1000000) - 1;
// Divide down the prescaler until it fits into 8 bits. We add up the number of ticks
// it takes to equal a microsecond interval.
while (prescaler > 0xff)
{
prescaler /= 2;
}
// Make sure the timer is off.
HW_ARMGLOBALTIMER_CONTROL.B.TIMER_ENABLE = 0;
// Clear counter.
HW_ARMGLOBALTIMER_COUNTERn_WR(0, 0);
HW_ARMGLOBALTIMER_COUNTERn_WR(1, 0);
// Set prescaler and clear other flags.
HW_ARMGLOBALTIMER_CONTROL_WR(BF_ARMGLOBALTIMER_CONTROL_PRESCALER(prescaler));
// Now turn on the timer.
HW_ARMGLOBALTIMER_CONTROL.B.TIMER_ENABLE = 1;
freq = get_main_clock(IPG_CLK);
epit_init(HW_EPIT1, CLKSRC_IPG_CLK, freq / 1000000,
SET_AND_FORGET, 10000, WAIT_MODE_EN | STOP_MODE_EN);
epit_counter_enable(HW_EPIT1, 10000, IRQ_MODE);
rt_hw_interrupt_install(IMX_INT_EPIT1, rt_hw_timer_isr, RT_NULL, "tick");
rt_hw_interrupt_umask(IMX_INT_EPIT1);
return 0;
}
