/**
*
* @brief System clock tick handler
*
* This routine handles the system clock tick interrupt. A TICK_EVENT event
* is pushed onto the kernel stack.
*
* @return N/A
*/
void _timer_int_handler(void *unused)
{
ARG_UNUSED(unused);
#if defined(CONFIG_HPET_TIMER_LEVEL_LOW) || defined(CONFIG_HPET_TIMER_LEVEL_HIGH)
/* Acknowledge interrupt */
*_HPET_GENERAL_INT_STATUS = 1;
#endif
#ifdef CONFIG_INT_LATENCY_BENCHMARK
uint32_t delta = *_HPET_MAIN_COUNTER_VALUE - main_count_expected_value;
if (_hw_irq_to_c_handler_latency > delta) {
/* keep the lowest value observed */
_hw_irq_to_c_handler_latency = delta;
}
/* compute the next expected main counter value */
main_count_expected_value += main_count_first_irq_value;
#endif
#ifndef CONFIG_TICKLESS_IDLE
/*
* one more tick has occurred -- don't need to do anything special since
* timer is already configured to interrupt on the following tick
*/
_sys_clock_tick_announce();
#else
/* see if interrupt was triggered while timer was being reprogrammed */
if (stale_irq_check) {
stale_irq_check = 0;
if (_hpetMainCounterAtomic() < *_HPET_TIMER0_COMPARATOR) {
return; /* ignore "stale" interrupt */
}
}
/* configure timer to expire on next tick */
counter_last_value = *_HPET_TIMER0_COMPARATOR;
*_HPET_TIMER0_CONFIG_CAPS |= HPET_Tn_VAL_SET_CNF;
*_HPET_TIMER0_COMPARATOR = counter_last_value + counter_load_value;
programmed_ticks = 1;
_sys_clock_final_tick_announce();
#endif /* !CONFIG_TICKLESS_IDLE */
}
void _timer_int_handler(void *unused /* parameter is not used */
)
{
ARG_UNUSED(unused);
#ifdef CONFIG_TICKLESS_IDLE
if (timer_mode == TIMER_MODE_ONE_SHOT) {
if (!timer_known_to_have_expired) {
uint32_t cycles;
/*
* The timer fired unexpectedly. This is due to one of two cases:
* 1. Entering tickless idle straddled a tick.
* 2. Leaving tickless idle straddled the final tick.
* Due to the timer reprogramming in _timer_idle_exit(), case #2
* can be handled as a fall-through.
*
* NOTE: Although the cycle count is supposed to stop decrementing
* once it hits zero in one-shot mode, not all targets implement
* this properly (and continue to decrement). Thus, we have to
* perform a second comparison to check for wrap-around.
*/
cycles = current_count_register_get();
if ((cycles > 0) && (cycles < programmed_cycles)) {
/* Case 1 */
_sys_idle_elapsed_ticks = 0;
}
}
/* Return the timer to periodic mode */
initial_count_register_set(cycles_per_tick - 1);
periodic_mode_set();
timer_known_to_have_expired = false;
timer_mode = TIMER_MODE_PERIODIC;
}
_sys_clock_final_tick_announce();
/* track the accumulated cycle count */
accumulated_cycle_count += cycles_per_tick * _sys_idle_elapsed_ticks;
#else
/* track the accumulated cycle count */
accumulated_cycle_count += cycles_per_tick;
_sys_clock_tick_announce();
#endif /*CONFIG_TICKLESS_IDLE*/
}
/**
*
* @brief System clock periodic tick handler
*
* This routine handles the system clock periodic tick interrupt. It always
* announces one tick.
*
* @return N/A
*/
void _timer_int_handler(void *unused)
{
ARG_UNUSED(unused);
/* clear the interrupt by writing 0 to IP bit of the control register */
timer0_control_register_set(_ARC_V2_TMR_CTRL_NH | _ARC_V2_TMR_CTRL_IE);
#ifdef CONFIG_TICKLESS_KERNEL
if (!programmed_ticks) {
if (_sys_clock_always_on) {
_sys_clock_tick_count = _get_elapsed_clock_time();
program_max_cycles();
}
return;
}
_sys_idle_elapsed_ticks = programmed_ticks;
/*
* Clear programmed ticks before announcing elapsed time so
* that recursive calls to _update_elapsed_time() will not
* announce already consumed elapsed time
*/
programmed_ticks = 0;
timer_expired = 1;
_sys_clock_tick_announce();
/* _sys_clock_tick_announce() could cause new programming */
if (!programmed_ticks && _sys_clock_always_on) {
_sys_clock_tick_count = _get_elapsed_clock_time();
program_max_cycles();
}
#else
#if defined(CONFIG_TICKLESS_IDLE)
timer0_limit_register_set(cycles_per_tick - 1);
__ASSERT_EVAL({},
u32_t timer_count = timer0_count_register_get(),
timer_count <= (cycles_per_tick - 1),
"timer_count: %d, limit %d\n", timer_count, cycles_per_tick - 1);
_sys_clock_final_tick_announce();
#else
_sys_clock_tick_announce();
#endif
update_accumulated_count();
#endif
}
/**
*
* @brief System clock tick handler
*
* This routine handles the system clock tick interrupt. A TICK_EVENT event
* is pushed onto the kernel stack.
*
* The symbol for this routine is either _timer_int_handler.
*
* @return N/A
*/
void _timer_int_handler(void *unused)
{
ARG_UNUSED(unused);
#ifdef CONFIG_EXECUTION_BENCHMARKING
extern void read_systick_start_of_tick_handler(void);
read_systick_start_of_tick_handler();
#endif
#ifdef CONFIG_KERNEL_EVENT_LOGGER_INTERRUPT
extern void _sys_k_event_logger_interrupt(void);
_sys_k_event_logger_interrupt();
#endif
#ifdef CONFIG_SYS_POWER_MANAGEMENT
s32_t numIdleTicks;
/*
* All interrupts are disabled when handling idle wakeup.
* For tickless idle, this ensures that the calculation and programming
* of
* the device for the next timer deadline is not interrupted.
* For non-tickless idle, this ensures that the clearing of the kernel
* idle
* state is not interrupted.
* In each case, _sys_power_save_idle_exit is called with interrupts
* disabled.
*/
__asm__(" cpsid i"); /* PRIMASK = 1 */
#ifdef CONFIG_TICKLESS_IDLE
#if defined(CONFIG_TICKLESS_KERNEL)
if (!idle_original_ticks) {
if (_sys_clock_always_on) {
_sys_clock_tick_count = _get_elapsed_clock_time();
/* clear overflow tracking flag as it is accounted */
timer_overflow = 0;
sysTickStop();
idle_original_ticks = max_system_ticks;
sysTickReloadSet(max_load_value);
sysTickStart();
sys_tick_reload();
}
__asm__(" cpsie i"); /* re-enable interrupts (PRIMASK = 0) */
_ExcExit();
return;
}
idle_mode = IDLE_NOT_TICKLESS;
_sys_idle_elapsed_ticks = idle_original_ticks;
/*
* Clear programmed ticks before announcing elapsed time so
* that recursive calls to _update_elapsed_time() will not
* announce already consumed elapsed time
*/
idle_original_ticks = 0;
_sys_clock_tick_announce();
/* _sys_clock_tick_announce() could cause new programming */
if (!idle_original_ticks && _sys_clock_always_on) {
_sys_clock_tick_count = _get_elapsed_clock_time();
/* clear overflow tracking flag as it is accounted */
timer_overflow = 0;
sysTickStop();
sysTickReloadSet(max_load_value);
sysTickStart();
sys_tick_reload();
}
#else
/*
* If this a wakeup from a completed tickless idle or after
* _timer_idle_exit has processed a partial idle, return
* to the normal tick cycle.
*/
if (timer_mode == TIMER_MODE_ONE_SHOT) {
sysTickStop();
sysTickReloadSet(default_load_value);
sysTickStart();
timer_mode = TIMER_MODE_PERIODIC;
}
/* set the number of elapsed ticks and announce them to the kernel */
if (idle_mode == IDLE_TICKLESS) {
/* tickless idle completed without interruption */
idle_mode = IDLE_NOT_TICKLESS;
_sys_idle_elapsed_ticks =
idle_original_ticks + 1; /* actual # of idle ticks */
_sys_clock_tick_announce();
} else {
_sys_clock_final_tick_announce();
}
/* accumulate total counter value */
clock_accumulated_count += default_load_value * _sys_idle_elapsed_ticks;
#endif
#else /* !CONFIG_TICKLESS_IDLE */
/*
* No tickless idle:
* Update the total tick count and announce this tick to the kernel.
*/
clock_accumulated_count += sys_clock_hw_cycles_per_tick;
_sys_clock_tick_announce();
#endif /* CONFIG_TICKLESS_IDLE */
numIdleTicks = _NanoIdleValGet(); /* get # of idle ticks requested */
if (numIdleTicks) {
_NanoIdleValClear(); /* clear kernel idle setting */
/*
* Complete idle processing.
* Note that for tickless idle, nothing will be done in
* _timer_idle_exit.
*/
_sys_power_save_idle_exit(numIdleTicks);
}
__asm__(" cpsie i"); /* re-enable interrupts (PRIMASK = 0) */
#else /* !CONFIG_SYS_POWER_MANAGEMENT */
/* accumulate total counter value */
clock_accumulated_count += sys_clock_hw_cycles_per_tick;
/*
* one more tick has occurred -- don't need to do anything special since
* timer is already configured to interrupt on the following tick
*/
_sys_clock_tick_announce();
#endif /* CONFIG_SYS_POWER_MANAGEMENT */
#ifdef CONFIG_EXECUTION_BENCHMARKING
extern void read_systick_end_of_tick_handler(void);
read_systick_end_of_tick_handler();
#endif
extern void _ExcExit(void);
_ExcExit();
}
