Subversion Repositories ao486

/*

 * Copyright (c) 2014, Aleksander Osman

 * All rights reserved.

 *

 * Redistribution and use in source and binary forms, with or without

 * modification, are permitted provided that the following conditions are met:

 *

 * * Redistributions of source code must retain the above copyright notice, this

 *   list of conditions and the following disclaimer.

 *

 * * 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.

 *

 * 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.

 */

package ao486.module.memory;

import java.util.HashMap;

import java.util.LinkedList;

import java.util.Random;

public class AvalonListener implements Listener {

    public interface AvalonInterface {

        void avalon_read(int cycle, long read_address) throws Exception;

        void avalon_write(int cycle, long write_address) throws Exception;

    }

    public AvalonListener(Random random, AvalonInterface avalon_interface) {

        this.random = random;

        this.avalon_interface = avalon_interface;

        memory = new HashMap<>();

        to_read = new LinkedList<>();

    }

    public void set_memory(long address, long value, int length) {

        for(int i=0; i<length; i++) {

            memory.put(address, (byte)(value & 0xFF));

//System.out.printf("[%x] = %x\n", address, value & 0xFF);

            address++;

            value >>= 8;

        }

    }

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

    public int get_memory(long address) {

        address &= 0xFFFFFFFF;

        if(memory.containsKey(address) == false) memory.put(address, (byte)random.nextInt());

        byte val = memory.get(address);

        return ((int)val) & 0xFF;

    }

    // must be continuous '1'

    boolean check_write_byteenable(long byteenable) {

        byteenable &= 0xF;

        boolean started = false;

        for(int i=0; i<4; i++) {

            boolean bit = (byteenable & 1) == 1;

            if(bit == false && started && byteenable > 0) return false;

            if(bit) started = true;

            byteenable >>= 1;

        }

        return true;

    }

    void append_written(long address, long data, long byteenable) {

        byteenable &= 0xF;

        for(int i=0; i<4; i++) {

            if((byteenable & 1) == 1) {

                memory.put(address+i,(byte)(data & 0xFF));

            }

            byteenable >>= 1;

            data >>= 8;

        }

    }

    @Override

    public void set_input(int cycle, Input input) throws Exception {

        if(state <= 0) {

            input.avm_waitrequest = random.nextInt(4) == 0;

        }

        if(state > 0) {

            int index = state-1;

            long value =

                    (((int)to_read.get(0) & 0xFF)     ) |

                    (((int)to_read.get(1) & 0xFF) << 8) |

                    (((int)to_read.get(2) & 0xFF) << 16) |

                    (((int)to_read.get(3) & 0xFF) << 24);

            input.avm_readdata      = value;

            input.avm_waitrequest   = scenario[index] >= 2;

            input.avm_readdatavalid = scenario[index] == 1 || scenario[index] == 3;

            if(input.avm_readdatavalid) for(int i=0; i<4; i++) to_read.removeFirst();

            state++;

        }

        was_waitrequest = input.avm_waitrequest;

    }

    @Override

    public void get_output(int cycle, Output output) throws Exception {

        if(output.avm_read && output.avm_write) throw new Exception("avm_read && avm_write");

        if(state == 0 && output.avm_read) {

            address    = output.avm_address;

            byteenable = output.avm_byteenable;

            burstcount = output.avm_burstcount;

            if(byteenable != 0xF) throw new Exception("Invalid read byteenable: " + byteenable);

            if(burstcount == 0)   throw new Exception("Invalid read burstcount: " + burstcount);

            state = 1;

            to_read.clear();

            for(int i=0; i<burstcount; i++) {

                for(int j=0; j<4; j++) to_read.add((byte)get_memory(address + i*4 + j));

            }

            LinkedList<Integer> vec = new LinkedList<>();

            for(int i=0; i<burstcount; ) {

                int val = random.nextInt(4);

                vec.add(val);

                if(val == 1 || val == 3) i++;

            }

            scenario = new int[vec.size()];

            for(int i=0; i<scenario.length; i++) {

                scenario[i] = vec.get(i);

                //System.out.println("--- scenario[" + i + "]: " + scenario[i]);

            }

        }

        else if(state > 0 && state > scenario.length) {

            avalon_interface.avalon_read(cycle, address);

            state = 0;

        }

        else if(state > 0) {

            if(address != output.avm_address)       throw new Exception(String.format("Invalid read address: %x != %x, cycle: %d, state: %d", address, output.avm_address, cycle, state));

            if(byteenable != output.avm_byteenable) throw new Exception("Invalid read byteenable: " + byteenable);

            if(burstcount != output.avm_burstcount) throw new Exception("Invalid read burstcount: " + burstcount);

            if(output.avm_write) throw new Exception("Invalid avm_write.");

        }

        else if(state == 0 && output.avm_write) {

            address    = output.avm_address;

            writedata  = output.avm_writedata;

            byteenable = output.avm_byteenable;

            burstcount = output.avm_burstcount;

            if(check_write_byteenable(byteenable) == false) throw new Exception("Invalid write byteenable: " + byteenable);

            if(burstcount == 0)                             throw new Exception("Invalid write burstcount: " + burstcount);

            state = -1;

            if(was_waitrequest == false) {

                append_written(address, writedata, byteenable);

                if(state == -burstcount) {

                    avalon_interface.avalon_write(cycle, address);

                    state = 0;

                }

                else {

                    state--;

                }

            }

            was_write_accepted = was_waitrequest == false;

        }

        else if(state < 0) {

            if(address != output.avm_address)       throw new Exception("Invalid write address: " + address);

            if(burstcount != output.avm_burstcount) throw new Exception("Invalid write burstcount: " + burstcount);

            if(was_write_accepted) {

                byteenable = output.avm_byteenable;

                writedata  = output.avm_writedata;

            }

            else {

                if(byteenable != output.avm_byteenable) throw new Exception("Invalid write byteenable: " + byteenable + ", output.byteenable: " + output.avm_byteenable + ", cycle: " + cycle);

                if(writedata  != output.avm_writedata)  throw new Exception("Invalid writedata: " + writedata);

            }

            was_write_accepted = was_waitrequest == false;

            if(check_write_byteenable(byteenable) == false) throw new Exception("Invalid write byteenable: " + byteenable);

            if(output.avm_write == false) throw new Exception("Invalid avm_write.");

            if(was_waitrequest == false) {

                append_written(address - 4*(state+1), writedata, byteenable);

                if(state == -burstcount) {

                    avalon_interface.avalon_write(cycle, address);

                    state = 0;

                }

                else {

                    state--;

                }

            }

        }

    }

    /*

    //Input

    boolean avm_waitrequest                 = false;

    boolean avm_readdatavalid               = false;

    long    avm_readdata                    = 0; //32

    //Output

    long    avm_address; //32

    long    avm_writedata; //32

    long    avm_byteenable; //4

    long    avm_burstcount; //3

    boolean avm_write;

    boolean avm_read;

    */

    LinkedList<Byte> to_read;

    boolean was_waitrequest;

    boolean was_read_accepted;

    boolean was_write_accepted;

    long    address;

    long    writedata;

    long    byteenable;

    long    burstcount;

    int state; // 0-idle; 1..- read; -1..- write;

    int scenario[]; //0- idle; 1- readdatavalid; 2- waitrequest; 3- readdatavalid && waitrequest

    Random random;

    HashMap<Long, Byte> memory;

    AvalonInterface avalon_interface;

}