xref: /gem5/src/systemc/ext/tlm_core/2/quantum/global_quantum.hh

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#ifndef __SYSTEMC_EXT_TLM_CORE_2_QUANTUM_GLOBAL_QUANTUM_HH__
#define __SYSTEMC_EXT_TLM_CORE_2_QUANTUM_GLOBAL_QUANTUM_HH__

#include "../../../core/sc_time.hh"

namespace tlm
{

//
// tlm_global_quantum class
//
// The global quantum is the maximum time an initiator can run ahead of
// SystemC time. All initiators should synchronize on timingpoints that
// are multiples of the global quantum value.
//
// sc_set_time_resolution can only be called before the first
// sc_time object is created. This means that after setting the
// global quantum it will not be possible to call sc_set_time_resolution.
// If sc_set_time_resolution must be called this must be done before
// the global quantum is set.
//

class tlm_global_quantum
{
  public:
    //
    // Returns a reference to the tlm_global_quantum singleton
    //
    static tlm_global_quantum &instance();

  public:

    //
    // Setter/getter for the global quantum
    //
    void set(const sc_core::sc_time &t) { m_global_quantum = t; }
    const sc_core::sc_time &get() const { return m_global_quantum; }

    //
    // This function will calculate the maximum value for the next local
    // quantum for an initiator. All initiators should synchronize on
    // integer multiples of the global quantum value. The value for the
    // local quantum of an initiator can be smaller, but should never be
    // greater than the value returned by this method.
    //
    sc_core::sc_time compute_local_quantum();

  protected:
    tlm_global_quantum();

  protected:
    sc_core::sc_time m_global_quantum;
};

} // namespace tlm

#endif /* __SYSTEMC_EXT_TLM_CORE_2_QUANTUM_GLOBAL_QUANTUM_HH__ */