Subversion Repositories openrisc_2011-10-31

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

// TAP reset action : implementation

// Copyright (C) 2009  Embecosm Limited <info@embecosm.com>

// Contributor Jeremy Bennett <jeremy.bennett@embecosm.com>

// This file is part of the Embecosm cycle accurate SystemC JTAG library.

// This program is free software: you can redistribute it and/or modify it

// under the terms of the GNU Lesser General Public License as published by

// the Free Software Foundation, either version 3 of the License, or (at your

// option) any later version.

// This program is distributed in the hope that it will be useful, but WITHOUT

// ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

// FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Lesser General Public

// License for more details.

// You should have received a copy of the GNU Lesser General Public License

// along with this program.  If not, see <http://www.gnu.org/licenses/>.

// The C/C++ parts of this program are commented throughout in a fashion

// suitable for processing with Doxygen.

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

// $Id$

#include "TapActionReset.h"

//! Constructor

//! Records the SystemC completion event with the parent. Sets the ::firstTime

//! flag, so the ::process () method will mark the tapStateMachine as not

//! reset.

//! @param[in] _doneEvent  The SystemC completion event

TapActionReset::TapActionReset (sc_core::sc_event *_doneEvent) :

  TapAction (_doneEvent),

  firstTime (true)

{

}       // TapActionReset ()

//! Process the reset action

//! This reuses the parent class ::checkResetDone() method. The first time we

//! are called, we mark the state machine as being in an inconsistent state,

//! to force the reset.

//! We use the value of the TAP state machine's resetDone flag to trigger

//! completion, since this is set on the final reset cycle. The result from

//! ::checkResetDone () is only true on the first cycle AFTER reset.

//! @see TapAction::

//! @param[in]  tapStateMachine  The TAP state machine with which this action

//!                              is associated. 

//! @param[out] tdi              The value to drive on TDI

//! @param[in]  tdo              The value currently on TDO

//! @param[out] tms              The value to drive on TMS

//! @return  True if the action is complete

bool

TapActionReset::process (TapStateMachine *tapStateMachine,

                         bool            &tdi,

                         bool             tdo,

                         bool            &tms)

{

  if (firstTime)

    {

      tapStateMachine->setResetDone (false);

      firstTime = false;

    }

  // Parent does the work (no warning message). Our result draws on the value

  // set in the tapStateMachine, to avoid an extra cycle.

  checkResetDone (tapStateMachine, tms, false);

  return tapStateMachine->getResetDone ();

}       // process ()