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with this work for additional information regarding copyright ownership.
Accellera licenses this file to you under the Apache License, Version 2.0
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/*****************************************************************************
sc_reset.cpp -- Support for reset.
Original Author: Andy Goodrich, Forte Design Systems
CHANGE LOG AT THE END OF THE FILE
*****************************************************************************/
#include "sysc/kernel/sc_simcontext.h"
#include "sysc/kernel/sc_reset.h"
#include "sysc/kernel/sc_process_handle.h"
#include "sysc/communication/sc_signal.h"
#include "sysc/communication/sc_signal_ports.h"
// THE SYSTEMC PROOF OF CONCEPT SIMULATOR RESET SIGNAL IMPLEMENTATION:
//
// (1) An instance of the sc_reset class is attached to each sc_signal<bool>
// that is used as a reset signal.
//
// (2) Each process that is senstive to a reset signal will be registered in the
// sc_reset class attached to that reset signal.
//
// (3) When a change in the value of a reset signal occurs it invokes the
// notify_processes() method of its sc_reset object instance. The
// notify_processes() method will call the reset_changed() method of each
// process that is registered with it to inform the process that
// state of the reset signal has changed.
//
// (4) A process may have multiple reset signals, so counters are kept for the
// number of active asynchronous, and synchronous, reset signals that are
// active. Those counters are incremented and decremented in the process'
// reset_changed() method.
//
// (5) When a process' semantics() method is called the current reset state is
// checked, and a reset sequence is initiated if the process is in reset.
// This will occur every time an SC_METHOD is dispatched. SC_CTHREAD and
// and SC_THREAD instances, only go through the semantics() method they
// initially start up. So the reset check is duplicated in the suspend_me()
// method, the tail of which will execute each time the thread is
// dispatched.
namespace sc_core {
class sc_reset_finder;
static sc_reset_finder* reset_finder_q=0; // Q of reset finders to reconcile.
//==============================================================================
// 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_reset_finder {
friend class sc_reset;
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& );
};
inline sc_reset_finder::sc_reset_finder(
bool async, const sc_in<bool>* port_p, bool level, sc_process_b* target_p) :
m_async(async), m_level(level), m_next_p(0), m_in_p(port_p), m_inout_p(0),
m_out_p(0), m_target_p(target_p)
{
m_next_p = reset_finder_q;
reset_finder_q = this;
}
inline sc_reset_finder::sc_reset_finder(
bool async, const sc_inout<bool>* port_p, bool level, sc_process_b* target_p
) :
m_async(async), m_level(level), m_next_p(0), m_in_p(0), m_inout_p(port_p),
m_out_p(0), m_target_p(target_p)
{
m_next_p = reset_finder_q;
reset_finder_q = this;
}
inline sc_reset_finder::sc_reset_finder(
bool async, const sc_out<bool>* port_p, bool level, sc_process_b* target_p
) :
m_async(async), m_level(level), m_next_p(0), m_in_p(0), m_inout_p(0),
m_out_p(port_p), m_target_p(target_p)
{
m_next_p = reset_finder_q;
reset_finder_q = this;
}
//------------------------------------------------------------------------------
//"sc_reset::notify_processes"
//
// Notify processes that there is a change in the reset signal value.
//------------------------------------------------------------------------------
void sc_reset::notify_processes()
{
bool active; // true if reset is active.
sc_reset_target* entry_p; // reset entry processing.
std::vector<sc_reset_target>::size_type process_i; // index of process resetting.
std::vector<sc_reset_target>::size_type process_n; // # of processes to reset.
bool value; // value of our signal.
value = m_iface_p->read();
process_n = m_targets.size();
for ( process_i = 0; process_i < process_n; process_i++ )
{
entry_p = &m_targets[process_i];
active = ( entry_p->m_level == value );
entry_p->m_process_p->reset_changed( entry_p->m_async, active );
}
}
//------------------------------------------------------------------------------
//"sc_reset::reconcile_resets"
//
// This static method processes the sc_reset_finders to establish the actual
// reset connections.
//
// Notes:
// (1) If reset is asserted we tell the process that it is in reset.
//------------------------------------------------------------------------------
void sc_reset::reconcile_resets()
{
const sc_signal_in_if<bool>* iface_p; // Interface to reset signal.
sc_reset_finder* next_p; // Next finder to process.
sc_reset_finder* now_p; // Finder currently processing.
sc_reset_target reset_target; // Target's reset entry.
sc_reset* reset_p; // Reset object to use.
for ( now_p = reset_finder_q; now_p; now_p = next_p )
{
next_p = now_p->m_next_p;
if ( now_p->m_in_p )
{
iface_p = DCAST<const sc_signal_in_if<bool>*>(
now_p->m_in_p->get_interface());
}
else if ( now_p->m_inout_p )
{
iface_p = DCAST<const sc_signal_in_if<bool>*>(
now_p->m_inout_p->get_interface());
}
else
{
iface_p = DCAST<const sc_signal_in_if<bool>*>(
now_p->m_out_p->get_interface());
}
assert( iface_p != 0 );
reset_p = iface_p->is_reset();
now_p->m_target_p->m_resets.push_back(reset_p);
reset_target.m_async = now_p->m_async;
reset_target.m_level = now_p->m_level;
reset_target.m_process_p = now_p->m_target_p;
reset_p->m_targets.push_back(reset_target);
if ( iface_p->read() == now_p->m_level ) // see note 1 above
now_p->m_target_p->initially_in_reset( now_p->m_async );
delete now_p;
}
}
//------------------------------------------------------------------------------
//"sc_reset::remove_process"
//
// This method removes the supplied process from the list of processes that
// should be notified when there is a change in the value of the reset signal.
//
// Arguments:
// process_p -> process to be removed.
//------------------------------------------------------------------------------
void sc_reset::remove_process( sc_process_b* process_p )
{
int process_i; // Index of process resetting.
int process_n; // # of processes to reset.
process_n = m_targets.size();
for ( process_i = 0; process_i < process_n; )
{
if ( m_targets[process_i].m_process_p == process_p )
{
m_targets[process_i] = m_targets[process_n-1];
process_n--;
m_targets.resize(process_n);
}
else
{
process_i++;
}
}
}
//------------------------------------------------------------------------------
//"sc_reset::reset_signal_is - ports"
//
// These overloads of the reset_signal_is() method will register the active
// process with the sc_reset object instance associated with the supplied port.
// If the port does not yet have a pointer to its sc_signal<bool> instance it
// will create an sc_reset_finder class object instance that will be used
// to set the process' reset information when the port has been bound.
//
// Arguments:
// async = true if the reset signal is asynchronous, false if not.
// port = port for sc_signal<bool> that will provide the reset signal.
// level = level at which reset is active, either true or false.
//------------------------------------------------------------------------------
void sc_reset::reset_signal_is( bool async, const sc_in<bool>& port, bool level)
{
const sc_signal_in_if<bool>* iface_p;
sc_process_b* process_p;
process_p = (sc_process_b*)sc_get_current_process_handle();
assert( process_p );
process_p->m_has_reset_signal = true;
switch ( process_p->proc_kind() )
{
case SC_THREAD_PROC_:
case SC_METHOD_PROC_:
case SC_CTHREAD_PROC_:
iface_p = DCAST<const sc_signal_in_if<bool>*>(port.get_interface());
if ( iface_p )
reset_signal_is( async, *iface_p, level );
else
new sc_reset_finder( async, &port, level, process_p );
break;
default:
SC_REPORT_ERROR(SC_ID_UNKNOWN_PROCESS_TYPE_, process_p->name());
break;
}
}
void sc_reset::reset_signal_is(
bool async, const sc_inout<bool>& port, bool level )
{
const sc_signal_in_if<bool>* iface_p;
sc_process_b* process_p;
process_p = (sc_process_b*)sc_get_current_process_handle();
assert( process_p );
process_p->m_has_reset_signal = true;
switch ( process_p->proc_kind() )
{
case SC_THREAD_PROC_:
case SC_METHOD_PROC_:
case SC_CTHREAD_PROC_:
iface_p = DCAST<const sc_signal_in_if<bool>*>(port.get_interface());
if ( iface_p )
reset_signal_is( async, *iface_p, level );
else
new sc_reset_finder( async, &port, level, process_p );
break;
default:
SC_REPORT_ERROR(SC_ID_UNKNOWN_PROCESS_TYPE_, process_p->name());
break;
}
}
void sc_reset::reset_signal_is(
bool async, const sc_out<bool>& port, bool level )
{
const sc_signal_in_if<bool>* iface_p;
sc_process_b* process_p;
process_p = (sc_process_b*)sc_get_current_process_handle();
assert( process_p );
process_p->m_has_reset_signal = true;
switch ( process_p->proc_kind() )
{
case SC_THREAD_PROC_:
case SC_METHOD_PROC_:
case SC_CTHREAD_PROC_:
iface_p = DCAST<const sc_signal_in_if<bool>*>(port.get_interface());
if ( iface_p )
reset_signal_is( async, *iface_p, level );
else
new sc_reset_finder( async, &port, level, process_p );
break;
default:
SC_REPORT_ERROR(SC_ID_UNKNOWN_PROCESS_TYPE_, process_p->name());
break;
}
}
//------------------------------------------------------------------------------
//"sc_reset::reset_signal_is"
//
// This static method will register the active process instance as being
// reset by the sc_signal<bool> whose interface has been supplied. If no
// sc_reset object instance has been attached to the sc_signal<bool> yet, it
// will be created and attached. The active process instance is pushed into
// the list of processes that the sc_reset object instance should notify if
// the value of the reset signal changes.
//
// Arguments:
// async = true if the reset signal is asynchronous, false if not.
// iface = interface for the reset signal.
// level = is the level at which reset is active, either true or false.
// Notes:
// (1) If reset is asserted we tell the process that it is in reset
// initially.
//------------------------------------------------------------------------------
void sc_reset::reset_signal_is(
bool async, const sc_signal_in_if<bool>& iface, bool level )
{
sc_process_b* process_p; // process adding reset for.
sc_reset_target reset_target; // entry to build for the process.
sc_reset* reset_p; // reset object.
process_p = sc_process_b::last_created_process_base();
assert( process_p );
process_p->m_has_reset_signal = true;
switch ( process_p->proc_kind() )
{
case SC_METHOD_PROC_:
case SC_CTHREAD_PROC_:
case SC_THREAD_PROC_:
reset_p = iface.is_reset();
process_p->m_resets.push_back(reset_p);
reset_target.m_async = async;
reset_target.m_level = level;
reset_target.m_process_p = process_p;
reset_p->m_targets.push_back(reset_target);
if ( iface.read() == level ) process_p->initially_in_reset( async );
break;
default:
SC_REPORT_ERROR(SC_ID_UNKNOWN_PROCESS_TYPE_, process_p->name());
break;
}
}
} // namespace sc_core
// $Log: sc_reset.cpp,v $
// Revision 1.16 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 1.15 2011/08/24 22:05:51 acg
// Torsten Maehne: initialization changes to remove warnings.
//
// Revision 1.14 2011/04/08 22:37:34 acg
// Andy Goodrich: documentation of the reset mechanism and additional
// documentation of methods. Removal of check for SC_METHODs in
// sc_reset_signal_is() that should not have been there.
//
// Revision 1.13 2011/03/20 15:13:01 acg
// Andy Goodrich: set the reset flag for async_reset_signal_is to catch
// the suspend() corner case.
//
// Revision 1.12 2011/03/20 13:43:23 acg
// Andy Goodrich: added async_signal_is() plus suspend() as a corner case.
//
// Revision 1.11 2011/03/06 19:57:11 acg
// Andy Goodrich: refinements for the illegal suspend - synchronous reset
// interaction.
//
// Revision 1.10 2011/02/18 20:27:14 acg
// Andy Goodrich: Updated Copyrights.
//
// Revision 1.9 2011/02/13 21:47:37 acg
// Andy Goodrich: update copyright notice.
//
// Revision 1.8 2011/02/01 21:08:26 acg
// Andy Goodrich: new multiple reset support.
//
// Revision 1.7 2011/01/06 18:04:38 acg
// Andy Goodrich: removed commented out code.
//
// Revision 1.6 2010/12/07 20:09:13 acg
// Andy Goodrich: removed sc_signal overloads since already have sc_signal_in_if overloads.
//
// Revision 1.5 2010/11/20 17:10:56 acg
// Andy Goodrich: reset processing changes for new IEEE 1666 standard.
//
// Revision 1.4 2009/05/22 16:06:29 acg
// Andy Goodrich: process control updates.
//
// Revision 1.3 2009/03/12 22:59:58 acg
// Andy Goodrich: updates for 2.4 stuff.
//
// 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 1.7 2006/12/02 20:58:19 acg
// Andy Goodrich: updates from 2.2 for IEEE 1666 support.
//
// Revision 1.5 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 1.4 2006/01/24 20:49:05 acg
// Andy Goodrich: changes to remove the use of deprecated features within the
// simulator, and to issue warning messages when deprecated features are used.
//
// Revision 1.3 2006/01/13 18:44:30 acg
// Added $Log to record CVS changes into the source.
//