sc_reset.h

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/*****************************************************************************

  sc_reset.h -- Process reset support.
*/
#if !defined(sc_reset_h_INCLUDED)
#define sc_reset_h_INCLUDED

#include "sysc/communication/sc_writer_policy.h"

#if defined(_MSC_VER) && !defined(SC_WIN_DLL_WARN)
#pragma warning(push)
#pragma warning(disable: 4251) // DLL import for std::vector
#endif

namespace sc_core {

// FORWARD CLASS REFERENCES:

template<typename DATA> class sc_signal_in_if;
template<typename IF, sc_writer_policy POL> class sc_signal;
template<typename DATA> class sc_in;
template<typename DATA> class sc_inout;
template<typename DATA> class sc_out;
template<typename SOURCE> class sc_spawn_reset;
class sc_reset;
class sc_process_b;

//==============================================================================
// CLASS sc_reset_target - RESET ENTRY FOR AN sc_process_b TARGET
//
// This class describes a reset condition associated with an sc_process_b
// instance. 
//==============================================================================
class SC_API sc_reset_target {
  public:
    bool          m_async;     // true asynchronous reset, false synchronous.
    bool          m_level;     // level for reset.
    sc_process_b* m_process_p; // process this reset entry is for.
};

inline std::ostream& operator << ( std::ostream& os, 
                                   const sc_reset_target& target )
{
    os << "[";
    os << target.m_async << ",";
    os << target.m_level << ",";
    os << target.m_process_p << ",";
    return os;
}


//==============================================================================
// sc_reset_finder - place holder class for a port reset signal until it is
//                   bound and an interface class is available. When the port
//                   has been bound the information in this class will be used
//                   to initialize its sc_reset object instance.
//==============================================================================
class SC_API sc_reset_finder {
    friend class sc_reset;
    friend class sc_simcontext;
public:
    sc_reset_finder( bool async, const sc_in<bool>* port_p, bool level,
                     sc_process_b* target_p);
    sc_reset_finder( bool async, const sc_inout<bool>* port_p, bool level,
                     sc_process_b* target_p);
    sc_reset_finder( bool async, const sc_out<bool>* port_p, bool level,
                     sc_process_b* target_p);

protected:
    bool                   m_async;     // True if asynchronous reset.
    bool                   m_level;     // Level for reset.
    sc_reset_finder*       m_next_p;    // Next reset finder in list.
    const sc_in<bool>*     m_in_p;      // Port for which reset is needed.
    const sc_inout<bool>*  m_inout_p;   // Port for which reset is needed.
    const sc_out<bool>*    m_out_p;     // Port for which reset is needed.
    sc_process_b*          m_target_p;  // Process to reset.

private: // disabled
    sc_reset_finder( const sc_reset_finder& );
    const sc_reset_finder& operator = ( const sc_reset_finder& );
};

//==============================================================================
// CLASS sc_reset - RESET INFORMATION FOR A RESET SIGNAL
//
// See the top of sc_reset.cpp for an explaination of how the reset mechanism
// is implemented.
//==============================================================================
class SC_API sc_reset {
    friend class sc_cthread_process;
    friend class sc_method_process; 
    friend class sc_module; 
    friend class sc_process_b;
    friend class sc_signal<bool, SC_ONE_WRITER>;
    friend class sc_signal<bool, SC_MANY_WRITERS>;
    friend class sc_signal<bool, SC_UNCHECKED_WRITERS>;
    friend class sc_simcontext;
    template<typename SOURCE> friend class sc_spawn_reset;
    friend class sc_thread_process;

  protected:
    static void reconcile_resets(sc_reset_finder* reset_finder_q);
    static void 
        reset_signal_is(bool async, const sc_signal_in_if<bool>& iface, 
                        bool level);
    static void 
        reset_signal_is( bool async, const sc_in<bool>& iface, bool level);
    static void 
        reset_signal_is( bool async, const sc_inout<bool>& iface, bool level);
    static void 
        reset_signal_is( bool async, const sc_out<bool>& iface, bool level);

  protected:
    sc_reset( const sc_signal_in_if<bool>* iface_p ) :
        m_iface_p(iface_p), m_targets() {}
    void notify_processes();
    void remove_process( sc_process_b* );

  protected:
    const sc_signal_in_if<bool>*  m_iface_p;  // Interface to read.
    std::vector<sc_reset_target>  m_targets;  // List of processes to reset.

  private: // disabled
    sc_reset( const sc_reset& );
    const sc_reset& operator = ( const sc_reset& );
};

// $Log: sc_reset.h,v $
// Revision 1.11  2011/08/26 20:46:10  acg
//  Andy Goodrich: moved the modification log to the end of the file to
//  eliminate source line number skew when check-ins are done.
//
// Revision 1.10  2011/08/24 22:05:51  acg
//  Torsten Maehne: initialization changes to remove warnings.
//
// Revision 1.9  2011/04/08 22:38:30  acg
//  Andy Goodrich: added comment pointing to the description of how the
//  reset mechanism works that is in sc_reset.cpp.
//
// Revision 1.8  2011/02/18 20:27:14  acg
//  Andy Goodrich: Updated Copyrights.
//
// Revision 1.7  2011/02/13 21:47:37  acg
//  Andy Goodrich: update copyright notice.
//
// Revision 1.6  2011/01/06 18:00:32  acg
//  Andy Goodrich: Removed commented out code.
//
// Revision 1.5  2010/12/07 20:09:14  acg
// Andy Goodrich: removed sc_signal signatures since already have sc_signal_in_if signatures.
//
// Revision 1.4  2010/11/20 17:10:57  acg
//  Andy Goodrich: reset processing changes for new IEEE 1666 standard.
//
// Revision 1.3  2009/05/22 16:06:29  acg
//  Andy Goodrich: process control updates.
//
// Revision 1.2  2008/05/22 17:06:26  acg
//  Andy Goodrich: updated copyright notice to include 2008.
//
// Revision 1.1.1.1  2006/12/15 20:20:05  acg
// SystemC 2.3
//
// Revision 1.6  2006/12/02 20:58:19  acg
//  Andy Goodrich: updates from 2.2 for IEEE 1666 support.
//
// Revision 1.4  2006/04/11 23:13:21  acg
//   Andy Goodrich: Changes for reduced reset support that only includes
//   sc_cthread, but has preliminary hooks for expanding to method and thread
//   processes also.
//
// Revision 1.3  2006/01/13 18:44:30  acg
// Added $Log to record CVS changes into the source.

} // namespace sc_core

#if defined(_MSC_VER) && !defined(SC_WIN_DLL_WARN)
#pragma warning(pop)
#endif

#endif // !defined(sc_reset_h_INCLUDED)