src/arch/power/pagetable.hh

/*
 * Copyright (c) 2002-2005 The Regents of The University of Michigan
 * Copyright (c) 2007 MIPS Technologies, Inc.
 * Copyright (c) 2007-2008 The Florida State University
 * Copyright (c) 2009 The University of Edinburgh
 * 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 __ARCH_POWER_PAGETABLE_H__
#define __ARCH_POWER_PAGETABLE_H__

#include "base/types.hh"
#include "sim/serialize.hh"

namespace gem5
{

namespace PowerISA
{

// ITB/DTB page table entry
struct PTE
{
    // What parts of the VAddr (from bits 28..11) should be used in
    // translation (includes Mask and MaskX from PageMask)
    Addr Mask;

    // Virtual Page Number (/2) (Includes VPN2 + VPN2X .. bits 31..11
    // from EntryHi)
    Addr VPN;

    // Address Space ID (8 bits) // Lower 8 bits of EntryHi
    uint8_t asid;

    // Global Bit - Obtained by an *AND* of EntryLo0 and EntryLo1 G bit
    bool G;

    /* Contents of Entry Lo0 */
    Addr PFN0; // Physical Frame Number - Even
    bool D0;   // Even entry Dirty Bit
    bool V0;   // Even entry Valid Bit
    uint8_t C0; // Cache Coherency Bits - Even

    /* Contents of Entry Lo1 */
    Addr PFN1; // Physical Frame Number - Odd
    bool D1;   // Odd entry Dirty Bit
    bool V1;   // Odd entry Valid Bit
    uint8_t C1; // Cache Coherency Bits (3 bits)

    // The next few variables are put in as optimizations to reduce TLB
    // lookup overheads. For a given Mask, what is the address shift amount
    // and what is the OffsetMask
    int AddrShiftAmount;
    int OffsetMask;

    bool
    Valid()
    {
        return (V0 | V1);
    };

    void serialize(CheckpointOut &cp) const;
    void unserialize(CheckpointIn &cp);
};

} // namespace PowerISA
} // namespace gem5

#endif // __ARCH_POWER_PAGETABLE_H__