/*
 * Copyright (c) 2009 Mark D. Hill and David A. Wood
 * 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;
 * neither the name of the copyright holders 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
 * OWNER 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.
 */

#ifndef MEMORYVECTOR_H
#define MEMORYVECTOR_H

#include "mem/ruby/common/Address.hh"

class DirectoryMemory;

/**
 *  MemoryVector holds memory data (DRAM only)
 */
class MemoryVector {
 public:
  MemoryVector();
  MemoryVector(uint32 size);
  ~MemoryVector();
  friend class DirectoryMemory;

  void setSize(uint32 size);  // destructive

  void write(const Address & paddr, uint8* data, int len);
  uint8* read(const Address & paddr, uint8* data, int len);

private:
  uint8* getBlockPtr(const PhysAddress & addr);

  uint32 m_size;
  uint8** m_pages;
  uint32 m_num_pages;
  const uint32 m_page_offset_mask;
};

inline
MemoryVector::MemoryVector()
  : m_page_offset_mask(4095)
{
  m_size = 0;
  m_num_pages = 0;
  m_pages = NULL;
}

inline
MemoryVector::MemoryVector(uint32 size)
  : m_page_offset_mask(4095)
{
  setSize(size);
}

inline
MemoryVector::~MemoryVector()
{
  for (int i=0; i<m_num_pages; i++) {
    if (m_pages[i] != 0) {
      delete [] m_pages[i];
    }
  }
  delete [] m_pages;
}

inline
void MemoryVector::setSize(uint32 size)
{
  if (m_pages != NULL){
    for (int i=0; i<m_num_pages; i++) {
      if (m_pages[i] != 0) {
        delete [] m_pages[i];
      }
    }
    delete [] m_pages;
  }
  m_size = size;
  assert(size%4096 == 0);
  m_num_pages = size >> 12;
  m_pages = new uint8*[m_num_pages];
  memset(m_pages, 0, m_num_pages * sizeof(uint8*));
}

inline
void MemoryVector::write(const Address & paddr, uint8* data, int len)
{
  assert(paddr.getAddress() + len <= m_size);
  uint32 page_num = paddr.getAddress() >> 12;
  if (m_pages[page_num] == 0) {
    bool all_zeros = true;
    for (int i=0;i<len;i++) {
      if (data[i] != 0) {
        all_zeros = false;
        break;
      }
    }
    if (all_zeros) return;
    m_pages[page_num] = new uint8[4096];
    memset(m_pages[page_num], 0, 4096);
    uint32 offset = paddr.getAddress() & m_page_offset_mask;
    memcpy(&m_pages[page_num][offset], data, len);
  } else {
    memcpy(&m_pages[page_num][paddr.getAddress()&m_page_offset_mask], data, len);
  }
}

inline
uint8* MemoryVector::read(const Address & paddr, uint8* data, int len)
{
  assert(paddr.getAddress() + len <= m_size);
  uint32 page_num = paddr.getAddress() >> 12;
  if (m_pages[page_num] == 0) {
    memset(data, 0, len);
  } else {
    memcpy(data, &m_pages[page_num][paddr.getAddress()&m_page_offset_mask], len);
  }
  return data;
}

inline
uint8* MemoryVector::getBlockPtr(const PhysAddress & paddr)
{
  uint32 page_num = paddr.getAddress() >> 12;
  if (m_pages[page_num] == 0) {
    m_pages[page_num] = new uint8[4096];
    memset(m_pages[page_num], 0, 4096);
  }
  return &m_pages[page_num][paddr.getAddress()&m_page_offset_mask];
}

#endif // MEMORYVECTOR_H