src/cpu/testers/traffic_gen/random_gen.hh

/*
 * Copyright (c) 2012-2013, 2017-2018 ARM Limited
 * All rights reserved
 *
 * The license below extends only to copyright in the software and shall
 * not be construed as granting a license to any other intellectual
 * property including but not limited to intellectual property relating
 * to a hardware implementation of the functionality of the software
 * licensed here under.  You may use the software subject to the license
 * terms below provided that you ensure that this notice is replicated
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 * modified or unmodified, in source code or in binary form.
 *
 * 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
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 * neither the name of the copyright holders nor the names of its
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 * this software without specific prior written permission.
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 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
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/**
 * @file
 * Declaration of the random generator that randomly selects
 * addresses within a range.
 */

#ifndef __CPU_TRAFFIC_GEN_RANDOM_GEN_HH__
#define __CPU_TRAFFIC_GEN_RANDOM_GEN_HH__

#include "base/bitfield.hh"
#include "base/intmath.hh"
#include "base_gen.hh"
#include "mem/packet.hh"

namespace gem5
{

/**
 * The random generator is similar to the linear one, but does
 * not generate sequential addresses. Instead it randomly
 * picks an address in the range, aligned to the block size.
 */
class RandomGen : public StochasticGen
{

  public:

    /**
     * Create a random address sequence generator. Set
     * min_period == max_period for a fixed inter-transaction
     * time.
     *
     * @param gen Traffic generator owning this sequence generator
     * @param _duration duration of this state before transitioning
     * @param requestor_id RequestorID related to the memory requests
     * @param start_addr Start address
     * @param end_addr End address
     * @param _blocksize Size used for transactions injected
     * @param cacheline_size cache line size in the system
     * @param min_period Lower limit of random inter-transaction time
     * @param max_period Upper limit of random inter-transaction time
     * @param read_percent Percent of transactions that are reads
     * @param data_limit Upper limit on how much data to read/write
     */
    RandomGen(SimObject &obj,
              RequestorID requestor_id, Tick _duration,
              Addr start_addr, Addr end_addr,
              Addr _blocksize, Addr cacheline_size,
              Tick min_period, Tick max_period,
              uint8_t read_percent, Addr data_limit)
        : StochasticGen(obj, requestor_id, _duration, start_addr, end_addr,
                        _blocksize, cacheline_size, min_period, max_period,
                        read_percent, data_limit),
          dataManipulated(0)
    { }

    void enter();

    PacketPtr getNextPacket();

    Tick nextPacketTick(bool elastic, Tick delay) const;

  protected:
    /**
     * Counter to determine the amount of data
     * manipulated. Used to determine if we should continue
     * generating requests.
     */
    Addr dataManipulated;
};

} // namespace gem5

#endif