HIFIVE1-VP/riscv.sc/incl/sysc/SiFive/gpio.h

////////////////////////////////////////////////////////////////////////////////
// Copyright (C) 2017, MINRES Technologies GmbH
// All rights reserved.
//
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions are met:
//
// 1. Redistributions of source code must retain the above copyright notice,
//    this list of conditions and the following disclaimer.
//
// 2. Redistributions in binary form must reproduce the above copyright notice,
//    this list of conditions and the following disclaimer in the documentation
//    and/or other materials provided with the distribution.
//
// 3. Neither the name of the copyright holder nor the names of its contributors
//    may be used to endorse or promote products derived from this software
//    without specific prior written permission.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
// AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
// IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
// ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
// LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
// CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
// SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
// INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
// CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
// ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
// POSSIBILITY OF SUCH DAMAGE.
//
// Contributors:
//       eyck@minres.com - initial implementation
//
//
////////////////////////////////////////////////////////////////////////////////

#ifndef _GPIO_H_
#define _GPIO_H_

#include "scc/tlm_target.h"
#include "scc/signal_target_mixin.h"
#include "scc/signal_initiator_mixin.h"
#include <tlm/tlm_signal.h>
#include "cci_configuration"

namespace sysc {

class gpio_regs;
class WsHandler;

class gpio : public sc_core::sc_module, public scc::tlm_target<> {
public:
    SC_HAS_PROCESS(gpio);
    sc_core::sc_in<sc_core::sc_time> clk_i;
    sc_core::sc_in<bool> rst_i;
    // sc_core::sc_inout_rv<32> pins_io;

    sc_core::sc_vector<scc::tlm_signal_logic_out> pins_o;
    sc_core::sc_vector<scc::tlm_signal_logic_in>  pins_i;

    sc_core::sc_vector<scc::tlm_signal_bool_opt_out> iof0_o;
    sc_core::sc_vector<scc::tlm_signal_bool_opt_out> iof1_o;
    sc_core::sc_vector<scc::tlm_signal_bool_opt_in>  iof0_i;
    sc_core::sc_vector<scc::tlm_signal_bool_opt_in>  iof1_i;

    gpio(sc_core::sc_module_name nm);
    virtual ~gpio() override; // need to keep it in source file because of fwd declaration of gpio_regs

    cci::cci_param<bool> write_to_ws;

protected:
    void clock_cb();
    void reset_cb();
    void update_pins();
    void before_end_of_elaboration();
    void pin_input(unsigned int tag, tlm::tlm_signal_gp<sc_logic>& gp, sc_core::sc_time& delay);
    void forward_pin_input(unsigned int tag, tlm::tlm_signal_gp<sc_logic>& gp);
    void iof_input(unsigned int tag, unsigned iof_idx, tlm::tlm_signal_gp<>& gp, sc_core::sc_time& delay);
    sc_core::sc_time clk;
    std::array<bool, 32> last_iof0, last_iof1;
    std::unique_ptr<gpio_regs> regs;
    std::shared_ptr<sysc::WsHandler> handler;

private:
    tlm::tlm_phase write_output(tlm::tlm_signal_gp<sc_dt::sc_logic>& gp, size_t i, sc_dt::sc_logic val);
    void enable_outputs(uint32_t new_data);
};

} /* namespace sysc */

#endif /* _GPIO_H_ */