xref: /gem5/src/mem/abstract_mem.hh

/*
 * Copyright (c) 2001-2005 The Regents of The University of Michigan
 * 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.
 */

/* @file
 */

#ifndef __PHYSICAL_MEMORY_HH__
#define __PHYSICAL_MEMORY_HH__

#include "base/range.hh"
#include "mem/memory.hh"

//
// Functional model for a contiguous block of physical memory. (i.e. RAM)
//
class PhysicalMemory : public Memory
{
  private:
    // prevent copying of a MainMemory object
    PhysicalMemory(const PhysicalMemory &specmem);
    const PhysicalMemory &operator=(const PhysicalMemory &specmem);

  protected:
    Addr base_addr;
    Addr pmem_size;
    uint8_t *pmem_addr;
    int page_ptr;

  public:
    Addr new_page();
    uint64_t size() { return pmem_size; }

  public:
    PhysicalMemory(const std::string &n);
    virtual ~PhysicalMemory();

  protected:
    // error handling for prot_* functions
    void prot_access_error(Addr addr, int size, const std::string &func);

  public:

    // Read/Write arbitrary amounts of data to simulated memory space
    virtual void prot_read(Addr addr, uint8_t *p, int size);
    virtual void prot_write(Addr addr, const uint8_t *p, int size);
    virtual void prot_memset(Addr addr, uint8_t val, int size);

    // fast back-door memory access for vtophys(), remote gdb, etc.
    uint64_t phys_read_qword(Addr addr) const;

  public:
    virtual void serialize(std::ostream &os);
    virtual void unserialize(Checkpoint *cp, const std::string &section);
};

PhysicalMemory::phys_read_qword(Addr addr) const
{
    if (addr + sizeof(uint64_t) > pmem_size)
        return 0;

    return *(uint64_t *)(pmem_addr + addr);
}


#endif //__PHYSICAL_MEMORY_HH__