/*
 * Copyright (c) 2007 The Hewlett-Packard Development Company
 * 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 hereunder.  You may use the software subject to the license
 * terms below provided that you ensure that this notice is replicated
 * unmodified and in its entirety in all distributions of the software,
 * 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
 * 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_X86_FAULTS_HH__
#define __ARCH_X86_FAULTS_HH__

#include <string>

#include "arch/x86/tlb.hh"
#include "base/bitunion.hh"
#include "base/logging.hh"
#include "cpu/null_static_inst.hh"
#include "sim/faults.hh"

namespace gem5
{

namespace X86ISA
{

// Base class for all x86 "faults" where faults is in the m5 sense
class X86FaultBase : public FaultBase
{
  protected:
    const char *faultName;
    const char *mnem;
    uint8_t vector;
    uint64_t errorCode;

    X86FaultBase(const char *_faultName, const char *_mnem,
                 const uint8_t _vector, uint64_t _errorCode=(uint64_t)-1) :
        faultName(_faultName), mnem(_mnem),
        vector(_vector), errorCode(_errorCode)
    {}

    const char *name() const override { return faultName; }
    virtual bool isBenign() { return true; }
    virtual const char *mnemonic() const { return mnem; }

    void invoke(ThreadContext *tc, const StaticInstPtr &inst=
                nullStaticInstPtr) override;

    virtual std::string describe() const;

  public:
    /**
     * Get the vector of an interrupt.
     *
     * @return interrupt vector number.
     */
    virtual uint8_t getVector() const { return vector; }
};

// Base class for x86 faults which behave as if the underlying instruction
// didn't happen.
class X86Fault : public X86FaultBase
{
  protected:
    using X86FaultBase::X86FaultBase;
};

// Base class for x86 traps which behave as if the underlying instruction
// completed.
class X86Trap : public X86FaultBase
{
  protected:
    using X86FaultBase::X86FaultBase;

    void invoke(ThreadContext *tc, const StaticInstPtr &inst=
                nullStaticInstPtr) override;
};

// Base class for x86 aborts which seem to be catastrophic failures.
class X86Abort : public X86FaultBase
{
  protected:
    using X86FaultBase::X86FaultBase;

    void invoke(ThreadContext *tc, const StaticInstPtr &inst=
                nullStaticInstPtr) override;
};

// Base class for x86 interrupts.
class X86Interrupt : public X86FaultBase
{
  protected:
    using X86FaultBase::X86FaultBase;
};

class UnimpInstFault : public FaultBase
{
  public:
    const char *
    name() const override
    {
        return "unimplemented_micro";
    }

    void
    invoke(ThreadContext *tc, const StaticInstPtr &inst=
            nullStaticInstPtr) override
    {
        panic("Unimplemented instruction!");
    }
};

// Below is a summary of the interrupt/exception information in the
// architecture manuals.

// Class  |  Type    | vector |               Cause                 | mnem
//------------------------------------------------------------------------
//Contrib   Fault     0         Divide Error                          #DE
//Benign    Either    1         Debug                                 #DB
//Benign    Interrupt 2         Non-Maskable-Interrupt                #NMI
//Benign    Trap      3         Breakpoint                            #BP
//Benign    Trap      4         Overflow                              #OF
//Benign    Fault     5         Bound-Range                           #BR
//Benign    Fault     6         Invalid-Opcode                        #UD
//Benign    Fault     7         Device-Not-Available                  #NM
//Benign    Abort     8         Double-Fault                          #DF
//                    9         Coprocessor-Segment-Overrun
//Contrib   Fault     10        Invalid-TSS                           #TS
//Contrib   Fault     11        Segment-Not-Present                   #NP
//Contrib   Fault     12        Stack                                 #SS
//Contrib   Fault     13        General-Protection                    #GP
//Either    Fault     14        Page-Fault                            #PF
//                    15        Reserved
//Benign    Fault     16        x87 Floating-Point Exception Pending  #MF
//Benign    Fault     17        Alignment-Check                       #AC
//Benign    Abort     18        Machine-Check                         #MC
//Benign    Fault     19        SIMD Floating-Point                   #XF
//                    20-29     Reserved
//Contrib   ?         30        Security Exception                    #SX
//                    31        Reserved
//Benign    Interrupt 0-255     External Interrupts                   #INTR
//Benign    Interrupt 0-255     Software Interrupts                   INTn

// Note that
class DivideError : public X86Fault
{
  public:
    DivideError() : X86Fault("Divide-Error", "#DE", 0) {}
};

class DebugException : public X86FaultBase
{
  public:
    DebugException() : X86FaultBase("Debug", "#DB", 1) {}
};

class NonMaskableInterrupt : public X86Interrupt
{
  public:
    NonMaskableInterrupt(uint8_t _vector) :
        X86Interrupt("Non Maskable Interrupt", "#NMI", 2, _vector)
    {}
};

class Breakpoint : public X86Trap
{
  public:
    Breakpoint() : X86Trap("Breakpoint", "#BP", 3) {}
};

class OverflowTrap : public X86Trap
{
  public:
    OverflowTrap() : X86Trap("Overflow", "#OF", 4) {}
};

class BoundRange : public X86Fault
{
  public:
    BoundRange() : X86Fault("Bound-Range", "#BR", 5) {}
};

class InvalidOpcode : public X86Fault
{
  public:
    InvalidOpcode() : X86Fault("Invalid-Opcode", "#UD", 6) {}

    void invoke(ThreadContext *tc, const StaticInstPtr &inst =
                nullStaticInstPtr) override;
};

class DeviceNotAvailable : public X86Fault
{
  public:
    DeviceNotAvailable() : X86Fault("Device-Not-Available", "#NM", 7) {}
};

class DoubleFault : public X86Abort
{
  public:
    DoubleFault() : X86Abort("Double-Fault", "#DF", 8, 0) {}
};

class InvalidTSS : public X86Fault
{
  public:
    InvalidTSS(uint32_t _errorCode) :
        X86Fault("Invalid-TSS", "#TS", 10, _errorCode)
    {}
};

class SegmentNotPresent : public X86Fault
{
  public:
    SegmentNotPresent(uint32_t _errorCode) :
        X86Fault("Segment-Not-Present", "#NP", 11, _errorCode)
    {}
};

class StackFault : public X86Fault
{
  public:
    StackFault(uint32_t _errorCode) : X86Fault("Stack", "#SS", 12, _errorCode)
    {}
};

class GeneralProtection : public X86Fault
{
  public:
    GeneralProtection(uint32_t _errorCode) :
        X86Fault("General-Protection", "#GP", 13, _errorCode)
    {}
};

class PageFault : public X86Fault
{
  protected:
    BitUnion32(PageFaultErrorCode)
        Bitfield<0> present;
        Bitfield<1> write;
        Bitfield<2> user;
        Bitfield<3> reserved;
        Bitfield<4> fetch;
    EndBitUnion(PageFaultErrorCode)

    Addr addr;

  public:
    PageFault(Addr _addr, uint32_t _errorCode) :
        X86Fault("Page-Fault", "#PF", 14, _errorCode), addr(_addr)
    {}

    PageFault(Addr _addr, bool present, BaseMMU::Mode mode,
            bool user, bool reserved) :
        X86Fault("Page-Fault", "#PF", 14, 0), addr(_addr)
    {
        PageFaultErrorCode code = 0;
        code.present = present;
        code.write = (mode == BaseMMU::Write);
        code.user = user;
        code.reserved = reserved;
        code.fetch = (mode == BaseMMU::Execute);
        errorCode = code;
    }

    void
    invoke(ThreadContext *tc, const StaticInstPtr &inst=
                nullStaticInstPtr);

    virtual std::string describe() const;
};

class X87FpExceptionPending : public X86Fault
{
  public:
    X87FpExceptionPending() :
        X86Fault("x87 Floating-Point Exception Pending", "#MF", 16)
    {}
};

class AlignmentCheck : public X86Fault
{
  public:
    AlignmentCheck() : X86Fault("Alignment-Check", "#AC", 17, 0) {}
};

class MachineCheck : public X86Abort
{
  public:
    MachineCheck() : X86Abort("Machine-Check", "#MC", 18) {}
};

class SIMDFloatingPointFault : public X86Fault
{
  public:
    SIMDFloatingPointFault() : X86Fault("SIMD Floating-Point", "#XF", 19) {}
};

class SecurityException : public X86FaultBase
{
  public:
    SecurityException() : X86FaultBase("Security Exception", "#SX", 30) {}
};

class ExternalInterrupt : public X86Interrupt
{
  public:
    ExternalInterrupt(uint8_t _vector) :
        X86Interrupt("External Interrupt", "#INTR", _vector)
    {}
};

class SystemManagementInterrupt : public X86Interrupt
{
  public:
    SystemManagementInterrupt() :
        X86Interrupt("System Management Interrupt", "#SMI", 0)
    {}
};

class InitInterrupt : public X86Interrupt
{
  public:
    InitInterrupt(uint8_t _vector) :
        X86Interrupt("INIT Interrupt", "#INIT", _vector)
    {}

    void invoke(ThreadContext *tc, const StaticInstPtr &inst=
                nullStaticInstPtr) override;
};

class StartupInterrupt : public X86Interrupt
{
  public:
    StartupInterrupt(uint8_t _vector) :
        X86Interrupt("Startup Interrupt", "#SIPI", _vector)
    {}

    void invoke(ThreadContext *tc, const StaticInstPtr &inst=
                nullStaticInstPtr) override;
};

} // namespace X86ISA
} // namespace gem5

#endif // __ARCH_X86_FAULTS_HH__