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

// TAP IR-Scan action: definition

// 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.

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

// $Id$

#ifndef TAP_ACTION_IR_SCAN__H

#define TAP_ACTION_IR_SCAN__H

#include <stdint.h>

#include "TapAction.h"

#include "TapStateMachine.h"

//! Class to represent a TAP IR-Scan action.

//! This class assumes that JTAG instruction registers are relatively

//! small. IEEE 1149.1 mandates at least 2 bits, although implementations

//! often have a wider range of instructions. The OpenRISC 1000 debug unit for

//! example uses 5 bits. 32-bits seems more than enough for the largest

//! applications.

class TapActionIRScan:public TapAction {

public:

        // Constructor

        TapActionIRScan(sc_core::sc_event * _doneEvent,

                        uint32_t _iRegIn, int _iRegSize);

        // Get the shifted out value

        uint32_t getIRegOut();

protected:

        // Process the action for IR-Scan

         bool process(TapStateMachine * tapStateMachine,

                      bool & tdi, bool tdo, bool & tms);

private:

        //! The value being shifted in

         uint32_t iRegIn;

        //! The number of bits to shift

        int iRegSize;

        //! The value shifted out

        uint32_t iRegOut;

        //! The number of bits shifted so far

        int bitsShifted;

        //! Where we are in the IR-scan process

        enum {

                SHIFT_IR_PREPARING,

                SHIFT_IR_SHIFTING,

                SHIFT_IR_UPDATING

        } iRScanState;

};                              // TapActionIRScan

#endif // TAP_ACTION_IR_SCAN__H