clock.cxx

ecos为实时嵌入式操作系统

            // The alarms are in ascending trigger order. When we
            // find an alarm that is later than us, we go in front of
            // it.
        
            if( list_alarm->trigger > alarm->trigger ) break;
            else alarm_list_ptr = &list_alarm->next;
        }
#endif
        // Insert the new alarm at *alarm_list_ptr

        alarm->next = *alarm_list_ptr;
        *alarm_list_ptr = alarm;
    
        Cyg_Scheduler::unlock();            
    }
}

// -------------------------------------------------------------------------
// Remove an alarm from this counter

void Cyg_Counter::rem_alarm( Cyg_Alarm *alarm )
{
    CYG_REPORT_FUNCTION();

    CYG_ASSERTCLASS( this, "Bad counter object" );
    CYG_ASSERTCLASS( alarm, "Bad alarm passed" );
    
    Cyg_Alarm **alarm_list_ptr;     // pointer to list

#if defined(CYGIMP_KERNEL_COUNTERS_SINGLE_LIST)

    alarm_list_ptr = &alarm_list;

#elif defined(CYGIMP_KERNEL_COUNTERS_MULTI_LIST)

    alarm_list_ptr = &(alarm_list[
        ((alarm->trigger+increment-1)/increment) %
                              CYGNUM_KERNEL_COUNTERS_MULTI_LIST_SIZE ] );
    
#else
#error "No CYGIMP_KERNEL_COUNTERS_x_LIST config"
#endif

    // Now that we have the list pointer, we can use common code for
    // both list organizations.

    Cyg_Scheduler::lock();

    CYG_INSTRUMENT_ALARM( REM, this, alarm );
    
    while( *alarm_list_ptr != NULL )
    {
        Cyg_Alarm *list_alarm = *alarm_list_ptr;

        CYG_ASSERTCLASS(list_alarm, "Bad alarm in counter list" );

        if( list_alarm == alarm ) break;
        else alarm_list_ptr = &list_alarm->next;
    }

    // If the alarm was found, remove it from the list.
    if( *alarm_list_ptr != NULL )
    {
        *alarm_list_ptr = alarm->next;
        alarm->enabled = false;
    }

    Cyg_Scheduler::unlock();            
}

//==========================================================================
// Constructor for clock object

Cyg_Clock::Cyg_Clock(
    cyg_resolution      res
    )
{
    CYG_REPORT_FUNCTION();

    resolution = res;
}

// -------------------------------------------------------------------------
// Destructor for Clock objects

Cyg_Clock::~Cyg_Clock()
{
    CYG_REPORT_FUNCTION();

}

// -------------------------------------------------------------------------
// 

#ifdef CYGDBG_USE_ASSERTS

bool Cyg_Clock::check_this( cyg_assert_class_zeal zeal) const
{
    // check that we have a non-NULL pointer first
    if( this == NULL ) return false;
    
    switch( zeal )
    {
    case cyg_system_test:
    case cyg_extreme:
    case cyg_thorough:
    case cyg_quick:
    case cyg_trivial:
    case cyg_none:
    default:
        break;
    };

    return true;
}

#endif

//==========================================================================
// Constructor for alarm object

Cyg_Alarm::Cyg_Alarm(
        Cyg_Counter     *c,             // Attached to this counter
        cyg_alarm_fn    *a,             // Call-back function
        CYG_ADDRWORD    d               // Call-back data
        )
{
    CYG_REPORT_FUNCTION();

    counter     = c;
    alarm       = a;
    data        = d;
    trigger     = 0;
    interval    = 0;
    enabled     = false;

#if defined(CYGIMP_KERNEL_COUNTERS_SINGLE_LIST) || defined(CYGIMP_KERNEL_COUNTERS_MULTI_LIST)
    next        = NULL;
#endif
    
}

Cyg_Alarm::Cyg_Alarm(){}

// -------------------------------------------------------------------------
// Destructor

Cyg_Alarm::~Cyg_Alarm()
{
    CYG_REPORT_FUNCTION();

    disable();
}

// -------------------------------------------------------------------------
// 

#ifdef CYGDBG_USE_ASSERTS

bool Cyg_Alarm::check_this( cyg_assert_class_zeal zeal) const
{
    // check that we have a non-NULL pointer first
    if( this == NULL ) return false;
    
    switch( zeal )
    {
    case cyg_system_test:
    case cyg_extreme:
    case cyg_thorough:
        if( trigger != 0 && !enabled ) return false;
    case cyg_quick:
    case cyg_trivial:
    case cyg_none:
    default:
        break;
    };

    return true;
}

#endif

// -------------------------------------------------------------------------
// Initialize Alarm and enable

void Cyg_Alarm::initialize(                
    cyg_tick_count    t,                // Absolute trigger time
    cyg_tick_count    i                 // Relative retrigger interval
    )
{
    CYG_REPORT_FUNCTION();

    // If already enabled, remove from counter
    
    if( enabled ) counter->rem_alarm(this);

    CYG_INSTRUMENT_ALARM( INIT,     this, 0 );
    CYG_INSTRUMENT_ALARM( TRIGGER,
                          ((cyg_uint32 *)&t)[0],
                          ((cyg_uint32 *)&t)[1] );
    CYG_INSTRUMENT_ALARM( INTERVAL,
                          ((cyg_uint32 *)&i)[0],
                          ((cyg_uint32 *)&i)[1] );
 
    trigger = t;
    interval = i;

    counter->add_alarm(this);
}

// -------------------------------------------------------------------------
// Synchronize with a past alarm stream that had been disabled,
// bring past times into synch, and the like.

void
Cyg_Alarm::synchronize( void )
{
    if( interval != 0 ) {
        // This expression sets the trigger to the next whole interval
        // at or after the current time. This means that alarms will
        // continue at the same intervals as if they had never been
        // disabled. The alternative would be to just set trigger to
        // (counter->counter + interval), but this is less satisfying
        // than preserving the original intervals. That behaviour can
        // always be obtained by using initialize() rather than
        // enable(), while the current behaviour would be more
        // difficult to achieve that way.
        cyg_tick_count d;
        d = counter->current_value() + interval - trigger;
        if ( d > interval ) {
            // then trigger was in the past, so resynchronize
            trigger += interval * ((d - 1) / interval );
        }
        // otherwise, we were just set up, so no worries.
    }
}

// -------------------------------------------------------------------------
// Ensure alarm enabled

void Cyg_Alarm::enable()
{
    if( !enabled )
    {
        // ensure the alarm time is in our future:
        synchronize();
        enabled = true;
        counter->add_alarm(this);
    }
}

//==========================================================================
// System clock object

#ifdef CYGVAR_KERNEL_COUNTERS_CLOCK

class Cyg_RealTimeClock
    : public Cyg_Clock
{
    Cyg_Interrupt       interrupt;

    static cyg_uint32 isr(cyg_vector vector, CYG_ADDRWORD data);

    static void dsr(cyg_vector vector, cyg_ucount32 count, CYG_ADDRWORD data);

    Cyg_RealTimeClock();

    static Cyg_RealTimeClock rtc;
};

Cyg_Clock::cyg_resolution rtc_resolution = CYGNUM_KERNEL_COUNTERS_RTC_RESOLUTION;

//Cyg_RealTimeClock Cyg_RealTimeClock::rtc __attribute__((init_priority (1)));

Cyg_RealTimeClock Cyg_RealTimeClock::rtc CYG_INIT_PRIORITY( CLOCK );

// -------------------------------------------------------------------------

Cyg_RealTimeClock::Cyg_RealTimeClock()
    : Cyg_Clock(rtc_resolution),
      interrupt(CYGNUM_HAL_INTERRUPT_RTC, 1, (CYG_ADDRWORD)this, isr, dsr)
{
    CYG_REPORT_FUNCTION();

    HAL_CLOCK_INITIALIZE( CYGNUM_KERNEL_COUNTERS_RTC_PERIOD );
    
    interrupt.attach();

    interrupt.unmask_interrupt(CYGNUM_HAL_INTERRUPT_RTC);

    Cyg_Clock::real_time_clock = this;
}

#ifdef HAL_CLOCK_LATENCY
cyg_tick_count total_clock_latency, total_clock_interrupts;
cyg_int32 min_clock_latency = 0x7FFFFFFF;
cyg_int32 max_clock_latency = 0;
bool measure_clock_latency = false;
#endif

// -------------------------------------------------------------------------

cyg_uint32 Cyg_RealTimeClock::isr(cyg_vector vector, CYG_ADDRWORD data)
{
//    CYG_REPORT_FUNCTION();

#ifdef HAL_CLOCK_LATENCY
    if (measure_clock_latency) {
        cyg_int32 delta;
        HAL_CLOCK_LATENCY(&delta);
        // Note: Ignore a latency of 0 when finding min_clock_latency.
        if (delta > 0) {
            // Valid delta measured
            total_clock_latency += delta;
            total_clock_interrupts++;
            if (min_clock_latency > delta) min_clock_latency = delta;
            if (max_clock_latency < delta) max_clock_latency = delta;
        }
    }
#endif

    CYG_INSTRUMENT_CLOCK( ISR, 0, 0);

    HAL_CLOCK_RESET( CYGNUM_HAL_INTERRUPT_RTC, CYGNUM_KERNEL_COUNTERS_RTC_PERIOD );

    Cyg_Interrupt::acknowledge_interrupt(CYGNUM_HAL_INTERRUPT_RTC);
        
    return Cyg_Interrupt::CALL_DSR;
}

// -------------------------------------------------------------------------

void Cyg_RealTimeClock::dsr(cyg_vector vector, cyg_ucount32 count, CYG_ADDRWORD data)
{
//    CYG_REPORT_FUNCTION();

    Cyg_RealTimeClock *rtc = (Cyg_RealTimeClock *)data;

    CYG_INSTRUMENT_CLOCK( TICK_START,
                          rtc->current_value_lo(),
                          rtc->current_value_hi());
                          
    rtc->tick( count );

#ifdef CYGSEM_KERNEL_SCHED_TIMESLICE
#if    0 == CYG_SCHED_UNIQUE_PRIORITIES

    // If timeslicing is enabled, call the scheduler to
    // handle it. But not if we have unique priorities.
    
    Cyg_Scheduler::scheduler.timeslice();

#endif
#endif

    CYG_INSTRUMENT_CLOCK( TICK_END,
                          rtc->current_value_lo(),
                          rtc->current_value_hi());
    
}

#endif

// -------------------------------------------------------------------------
// EOF common/clock.cxx