clock.hpp

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/*
 * Copyright (C) 2014, 2018 Pavel Kirienko <pavel.kirienko@gmail.com>
 * Kinetis Port Author David Sidrane <david_s5@nscdg.com>
 */

#pragma once

#include <uavcan_kinetis/build_config.hpp>
#include <uavcan/driver/system_clock.hpp>

namespace uavcan_kinetis
{

namespace clock
{
/**
 * Starts the clock.
 * Can be called multiple times, only the first call will be effective.
 */
void init();

/**
 * Returns current monotonic time since the moment when clock::init() was called.
 * This function is thread safe.
 */
uavcan::MonotonicTime getMonotonic();

/**
 * Sets the driver's notion of the system UTC. It should be called
 * at startup and any time the system clock is updated from an
 * external source that is not the UAVCAN Timesync master.
 * This function is thread safe.
 */
void setUtc(uavcan::UtcTime time);

/**
 * Returns UTC time if it has been set, otherwise returns zero time.
 * This function is thread safe.
 */
uavcan::UtcTime getUtc();

/**
 * Performs UTC phase and frequency adjustment.
 * The UTC time will be zero until first adjustment has been performed.
 * This function is thread safe.
 */
void adjustUtc(uavcan::UtcDuration adjustment);

/**
 * UTC clock synchronization parameters
 */
struct UtcSyncParams {
    float offset_p;                        ///< PPM per one usec error
    float rate_i;                          ///< PPM per one PPM error for second
    float rate_error_corner_freq;
    float max_rate_correction_ppm;
    float lock_thres_rate_ppm;
    uavcan::UtcDuration lock_thres_offset;
    uavcan::UtcDuration min_jump;          ///< Min error to jump rather than change rate

    UtcSyncParams()
        : offset_p(0.01F),
          rate_i(0.02F),
          rate_error_corner_freq(0.01F),
          max_rate_correction_ppm(300.0F),
          lock_thres_rate_ppm(2.0F),
          lock_thres_offset(uavcan::UtcDuration::fromMSec(4)),
          min_jump(uavcan::UtcDuration::fromMSec(10))
    {
    }
};

/**
 * Clock rate error.
 * Positive if the hardware timer is slower than reference time.
 * This function is thread safe.
 */
float getUtcRateCorrectionPPM();

/**
 * Number of non-gradual adjustments performed so far.
 * Ideally should be zero.
 * This function is thread safe.
 */
uavcan::uint32_t getUtcJumpCount();

/**
 * Whether UTC is synchronized and locked.
 * This function is thread safe.
 */
bool isUtcLocked();

/**
 * UTC sync params get/set.
 * Both functions are thread safe.
 */
UtcSyncParams getUtcSyncParams();
void setUtcSyncParams(const UtcSyncParams &params);

}

/**
 * Adapter for uavcan::ISystemClock.
 */
class SystemClock : public uavcan::ISystemClock
    , uavcan::Noncopyable
{
    SystemClock()
    {
    }

    virtual void adjustUtc(uavcan::UtcDuration adjustment)
    {
        clock::adjustUtc(adjustment);
    }

public:
    virtual uavcan::MonotonicTime getMonotonic() const
    {
        return clock::getMonotonic();
    }
    virtual uavcan::UtcTime getUtc()             const
    {
        return clock::getUtc();
    }

    /**
     * Calls clock::init() as needed.
     * This function is thread safe.
     */
    static SystemClock &instance();
};

}