packet.hh

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/*
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 *
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 * 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
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 * Copyright (c) 2010,2015 Advanced Micro Devices, Inc.
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#ifndef __MEM_PACKET_HH__
#define __MEM_PACKET_HH__
 
#include <bitset>
#include <cassert>
#include <initializer_list>
#include <list>
 
#include "base/addr_range.hh"
#include "base/cast.hh"
#include "base/compiler.hh"
#include "base/flags.hh"
#include "base/logging.hh"
#include "base/printable.hh"
#include "base/types.hh"
#include "mem/htm.hh"
#include "mem/request.hh"
#include "sim/byteswap.hh"
 
namespace gem5
{
 
class Packet;
typedef Packet *PacketPtr;
typedef uint8_t* PacketDataPtr;
typedef std::list<PacketPtr> PacketList;
typedef uint64_t PacketId;
 
class MemCmd
{
    friend class Packet;
 
  public:
    enum Command
    {
        InvalidCmd,
        ReadReq,
        ReadResp,
        ReadRespWithInvalidate,
        WriteReq,
        WriteResp,
        WriteCompleteResp,
        WritebackDirty,
        WritebackClean,
        WriteClean,            // writes dirty data below without evicting
        CleanEvict,
        SoftPFReq,
        SoftPFExReq,
        HardPFReq,
        SoftPFResp,
        HardPFResp,
        WriteLineReq,
        UpgradeReq,
        SCUpgradeReq,           // Special "weak" upgrade for StoreCond
        UpgradeResp,
        SCUpgradeFailReq,       // Failed SCUpgradeReq in MSHR (never sent)
        UpgradeFailResp,        // Valid for SCUpgradeReq only
        ReadExReq,
        ReadExResp,
        ReadCleanReq,
        ReadSharedReq,
        LoadLockedReq,
        StoreCondReq,
        StoreCondFailReq,       // Failed StoreCondReq in MSHR (never sent)
        StoreCondResp,
        LockedRMWReadReq,
        LockedRMWReadResp,
        LockedRMWWriteReq,
        LockedRMWWriteResp,
        SwapReq,
        SwapResp,
        // MessageReq and MessageResp are deprecated.
        MemFenceReq = SwapResp + 3,
        MemSyncReq,  // memory synchronization request (e.g., cache invalidate)
        MemSyncResp, // memory synchronization response
        MemFenceResp,
        CleanSharedReq,
        CleanSharedResp,
        CleanInvalidReq,
        CleanInvalidResp,
        // Error responses
        // @TODO these should be classified as responses rather than
        // requests; coding them as requests initially for backwards
        // compatibility
        InvalidDestError,  // packet dest field invalid
        BadAddressError,   // memory address invalid
        FunctionalReadError, // unable to fulfill functional read
        FunctionalWriteError, // unable to fulfill functional write
        // Fake simulator-only commands
        PrintReq,       // Print state matching address
        FlushReq,      //request for a cache flush
        InvalidateReq,   // request for address to be invalidated
        InvalidateResp,
        // hardware transactional memory
        HTMReq,
        HTMReqResp,
        HTMAbort,
        // Tlb shootdown
        TlbiExtSync,
        NUM_MEM_CMDS
    };
 
  private:
    enum Attribute
    {
        IsRead,         
        IsWrite,        
        IsUpgrade,
        IsInvalidate,
        IsClean,        
        NeedsWritable,  
        IsRequest,      
        IsResponse,     
        NeedsResponse,  
        IsEviction,
        IsSWPrefetch,
        IsHWPrefetch,
        IsLlsc,         
        IsLockedRMW,    
        HasData,        
        IsError,        
        IsPrint,        
        IsFlush,        
        FromCache,      
        NUM_COMMAND_ATTRIBUTES
    };
 
    static constexpr unsigned long long
    buildAttributes(std::initializer_list<Attribute> attrs)
    {
        unsigned long long ret = 0;
        for (const auto &attr: attrs)
            ret |= (1ULL << attr);
        return ret;
    }
 
    struct CommandInfo
    {
        const std::bitset<NUM_COMMAND_ATTRIBUTES> attributes;
        const Command response;
        const std::string str;
 
        CommandInfo(std::initializer_list<Attribute> attrs,
                Command _response, const std::string &_str) :
            attributes(buildAttributes(attrs)), response(_response), str(_str)
        {}
    };
 
    static const CommandInfo commandInfo[];
 
  private:
 
    Command cmd;
 
    bool
    testCmdAttrib(MemCmd::Attribute attrib) const
    {
        return commandInfo[cmd].attributes[attrib] != 0;
    }
 
  public:
 
    bool isRead() const            { return testCmdAttrib(IsRead); }
    bool isWrite() const           { return testCmdAttrib(IsWrite); }
    bool isUpgrade() const         { return testCmdAttrib(IsUpgrade); }
    bool isRequest() const         { return testCmdAttrib(IsRequest); }
    bool isResponse() const        { return testCmdAttrib(IsResponse); }
    bool needsWritable() const     { return testCmdAttrib(NeedsWritable); }
    bool needsResponse() const     { return testCmdAttrib(NeedsResponse); }
    bool isInvalidate() const      { return testCmdAttrib(IsInvalidate); }
    bool isEviction() const        { return testCmdAttrib(IsEviction); }
    bool isClean() const           { return testCmdAttrib(IsClean); }
    bool fromCache() const         { return testCmdAttrib(FromCache); }
 
    bool isWriteback() const       { return testCmdAttrib(IsEviction) &&
                                            testCmdAttrib(HasData); }
 
    bool hasData() const        { return testCmdAttrib(HasData); }
    bool isLLSC() const         { return testCmdAttrib(IsLlsc); }
    bool isLockedRMW() const    { return testCmdAttrib(IsLockedRMW); }
    bool isSWPrefetch() const   { return testCmdAttrib(IsSWPrefetch); }
    bool isHWPrefetch() const   { return testCmdAttrib(IsHWPrefetch); }
    bool isPrefetch() const     { return testCmdAttrib(IsSWPrefetch) ||
                                         testCmdAttrib(IsHWPrefetch); }
    bool isError() const        { return testCmdAttrib(IsError); }
    bool isPrint() const        { return testCmdAttrib(IsPrint); }
    bool isFlush() const        { return testCmdAttrib(IsFlush); }
 
    bool
    isDemand() const
    {
        return (cmd == ReadReq || cmd == WriteReq ||
                cmd == WriteLineReq || cmd == ReadExReq ||
                cmd == ReadCleanReq || cmd == ReadSharedReq);
    }
 
    Command
    responseCommand() const
    {
        return commandInfo[cmd].response;
    }
 
    const std::string &toString() const { return commandInfo[cmd].str; }
    int toInt() const { return (int)cmd; }
 
    MemCmd(Command _cmd) : cmd(_cmd) { }
    MemCmd(int _cmd) : cmd((Command)_cmd) { }
    MemCmd() : cmd(InvalidCmd) { }
 
    bool operator==(MemCmd c2) const { return (cmd == c2.cmd); }
    bool operator!=(MemCmd c2) const { return (cmd != c2.cmd); }
};
 
class Packet : public Printable
{
  public:
    typedef uint32_t FlagsType;
    typedef gem5::Flags<FlagsType> Flags;
 
  private:
    enum : FlagsType
    {
        // Flags to transfer across when copying a packet
        COPY_FLAGS             = 0x000000FF,
 
        // Flags that are used to create reponse packets
        RESPONDER_FLAGS        = 0x00000009,
 
        // Does this packet have sharers (which means it should not be
        // considered writable) or not. See setHasSharers below.
        HAS_SHARERS            = 0x00000001,
 
        // Special control flags
        EXPRESS_SNOOP          = 0x00000002,
 
        RESPONDER_HAD_WRITABLE = 0x00000004,
 
        // Snoop co-ordination flag to indicate that a cache is
        // responding to a snoop. See setCacheResponding below.
        CACHE_RESPONDING       = 0x00000008,
 
        // The writeback/writeclean should be propagated further
        // downstream by the receiver
        WRITE_THROUGH          = 0x00000010,
 
        // Response co-ordination flag for cache maintenance
        // operations
        SATISFIED              = 0x00000020,
 
        // hardware transactional memory
 
        // Indicates that this packet/request has returned from the
        // cache hierarchy in a failed transaction. The core is
        // notified like this.
        FAILS_TRANSACTION      = 0x00000040,
 
        // Indicates that this packet/request originates in the CPU executing
        // in transactional mode, i.e. in a transaction.
        FROM_TRANSACTION       = 0x00000080,
 
        VALID_ADDR             = 0x00000100,
        VALID_SIZE             = 0x00000200,
 
        STATIC_DATA            = 0x00001000,
        DYNAMIC_DATA           = 0x00002000,
 
        SUPPRESS_FUNC_ERROR    = 0x00008000,
 
        // Signal block present to squash prefetch and cache evict packets
        // through express snoop flag
        BLOCK_CACHED          = 0x00010000
    };
 
    Flags flags;
 
  public:
    typedef MemCmd::Command Command;
 
    MemCmd cmd;
 
    const PacketId id;
 
    RequestPtr req;
 
  private:
    PacketDataPtr data;
 
    Addr addr;
 
    bool _isSecure;
 
    unsigned size;
 
    std::vector<bool> bytesValid;
 
    // Quality of Service priority value
    uint8_t _qosValue;
 
    // hardware transactional memory
 
    HtmCacheFailure htmReturnReason;
 
    uint64_t htmTransactionUid;
 
  public:
 
    uint32_t headerDelay;
 
    uint32_t snoopDelay;
 
    uint32_t payloadDelay;
 
    struct SenderState
    {
        SenderState* predecessor;
        SenderState() : predecessor(NULL) {}
        virtual ~SenderState() {}
    };
 
    class PrintReqState : public SenderState
    {
      private:
        struct LabelStackEntry
        {
            const std::string label;
            std::string *prefix;
            bool labelPrinted;
            LabelStackEntry(const std::string &_label, std::string *_prefix);
        };
 
        typedef std::list<LabelStackEntry> LabelStack;
        LabelStack labelStack;
 
        std::string *curPrefixPtr;
 
      public:
        std::ostream &os;
        const int verbosity;
 
        PrintReqState(std::ostream &os, int verbosity = 0);
        ~PrintReqState();
 
        const std::string &curPrefix() { return *curPrefixPtr; }
 
        void pushLabel(const std::string &lbl,
                       const std::string &prefix = "  ");
 
        void popLabel();
 
        void printLabels();
 
        void printObj(Printable *obj);
    };
 
    SenderState *senderState;
 
    void pushSenderState(SenderState *sender_state);
 
    SenderState *popSenderState();
 
    template <typename T>
    T * findNextSenderState() const
    {
        T *t = NULL;
        SenderState* sender_state = senderState;
        while (t == NULL && sender_state != NULL) {
            t = dynamic_cast<T*>(sender_state);
            sender_state = sender_state->predecessor;
        }
        return t;
    }
 
    const std::string &cmdString() const { return cmd.toString(); }
 
    inline int cmdToIndex() const { return cmd.toInt(); }
 
    bool isRead() const              { return cmd.isRead(); }
    bool isWrite() const             { return cmd.isWrite(); }
    bool isDemand() const            { return cmd.isDemand(); }
    bool isUpgrade()  const          { return cmd.isUpgrade(); }
    bool isRequest() const           { return cmd.isRequest(); }
    bool isResponse() const          { return cmd.isResponse(); }
    bool needsWritable() const
    {
        // we should never check if a response needsWritable, the
        // request has this flag, and for a response we should rather
        // look at the hasSharers flag (if not set, the response is to
        // be considered writable)
        assert(isRequest());
        return cmd.needsWritable();
    }
    bool needsResponse() const       { return cmd.needsResponse(); }
    bool isInvalidate() const        { return cmd.isInvalidate(); }
    bool isEviction() const          { return cmd.isEviction(); }
    bool isClean() const             { return cmd.isClean(); }
    bool fromCache() const           { return cmd.fromCache(); }
    bool isWriteback() const         { return cmd.isWriteback(); }
    bool hasData() const             { return cmd.hasData(); }
    bool hasRespData() const
    {
        MemCmd resp_cmd = cmd.responseCommand();
        return resp_cmd.hasData();
    }
    bool isLLSC() const              { return cmd.isLLSC(); }
    bool isLockedRMW() const         { return cmd.isLockedRMW(); }
    bool isError() const             { return cmd.isError(); }
    bool isPrint() const             { return cmd.isPrint(); }
    bool isFlush() const             { return cmd.isFlush(); }
 
    bool isWholeLineWrite(unsigned blk_size)
    {
        return (cmd == MemCmd::WriteReq || cmd == MemCmd::WriteLineReq) &&
            getOffset(blk_size) == 0 && getSize() == blk_size;
    }
 
 
    void setCacheResponding()
    {
        assert(isRequest());
        assert(!flags.isSet(CACHE_RESPONDING));
        flags.set(CACHE_RESPONDING);
    }
    bool cacheResponding() const { return flags.isSet(CACHE_RESPONDING); }
    void setHasSharers()    { flags.set(HAS_SHARERS); }
    bool hasSharers() const { return flags.isSet(HAS_SHARERS); }
 
    void setExpressSnoop()      { flags.set(EXPRESS_SNOOP); }
    bool isExpressSnoop() const { return flags.isSet(EXPRESS_SNOOP); }
 
    void setResponderHadWritable()
    {
        assert(cacheResponding());
        assert(!responderHadWritable());
        flags.set(RESPONDER_HAD_WRITABLE);
    }
    bool responderHadWritable() const
    { return flags.isSet(RESPONDER_HAD_WRITABLE); }
 
    void copyResponderFlags(const PacketPtr pkt);
 
    void setWriteThrough()
    {
        assert(cmd.isWrite() &&
               (cmd.isEviction() || cmd == MemCmd::WriteClean));
        flags.set(WRITE_THROUGH);
    }
    void clearWriteThrough() { flags.clear(WRITE_THROUGH); }
    bool writeThrough() const { return flags.isSet(WRITE_THROUGH); }
 
    void setSatisfied()
    {
        assert(cmd.isClean());
        assert(!flags.isSet(SATISFIED));
        flags.set(SATISFIED);
    }
    bool satisfied() const { return flags.isSet(SATISFIED); }
 
    void setSuppressFuncError()     { flags.set(SUPPRESS_FUNC_ERROR); }
    bool suppressFuncError() const  { return flags.isSet(SUPPRESS_FUNC_ERROR); }
    void setBlockCached()          { flags.set(BLOCK_CACHED); }
    bool isBlockCached() const     { return flags.isSet(BLOCK_CACHED); }
    void clearBlockCached()        { flags.clear(BLOCK_CACHED); }
 
    inline uint8_t qosValue() const { return _qosValue; }
 
    inline void qosValue(const uint8_t qos_value)
    { _qosValue = qos_value; }
 
    inline RequestorID requestorId() const { return req->requestorId(); }
 
    // Network error conditions... encapsulate them as methods since
    // their encoding keeps changing (from result field to command
    // field, etc.)
    void
    setBadAddress()
    {
        assert(isResponse());
        cmd = MemCmd::BadAddressError;
    }
 
    void copyError(Packet *pkt) { assert(pkt->isError()); cmd = pkt->cmd; }
 
    Addr getAddr() const { assert(flags.isSet(VALID_ADDR)); return addr; }
    void setAddr(Addr _addr) { assert(flags.isSet(VALID_ADDR)); addr = _addr; }
 
    unsigned getSize() const  { assert(flags.isSet(VALID_SIZE)); return size; }
 
    AddrRange getAddrRange() const;
 
    Addr getOffset(unsigned int blk_size) const
    {
        return getAddr() & Addr(blk_size - 1);
    }
 
    Addr getBlockAddr(unsigned int blk_size) const
    {
        return getAddr() & ~(Addr(blk_size - 1));
    }
 
    bool isSecure() const
    {
        assert(flags.isSet(VALID_ADDR));
        return _isSecure;
    }
 
    AtomicOpFunctor *getAtomicOp() const { return req->getAtomicOpFunctor(); }
    bool isAtomicOp() const { return req->isAtomic(); }
 
    void
    convertScToWrite()
    {
        assert(isLLSC());
        assert(isWrite());
        cmd = MemCmd::WriteReq;
    }
 
    void
    convertLlToRead()
    {
        assert(isLLSC());
        assert(isRead());
        cmd = MemCmd::ReadReq;
    }
 
    Packet(const RequestPtr &_req, MemCmd _cmd)
        :  cmd(_cmd), id((PacketId)_req.get()), req(_req),
           data(nullptr), addr(0), _isSecure(false), size(0),
           _qosValue(0),
           htmReturnReason(HtmCacheFailure::NO_FAIL),
           htmTransactionUid(0),
           headerDelay(0), snoopDelay(0),
           payloadDelay(0), senderState(NULL)
    {
        flags.clear();
        if (req->hasPaddr()) {
            addr = req->getPaddr();
            flags.set(VALID_ADDR);
            _isSecure = req->isSecure();
        }
 
        if (req->isHTMCmd()) {
            flags.set(VALID_ADDR);
            assert(addr == 0x0);
        }
        if (req->hasSize()) {
            size = req->getSize();
            flags.set(VALID_SIZE);
        }
    }
 
    Packet(const RequestPtr &_req, MemCmd _cmd, int _blkSize, PacketId _id = 0)
        :  cmd(_cmd), id(_id ? _id : (PacketId)_req.get()), req(_req),
           data(nullptr), addr(0), _isSecure(false),
           _qosValue(0),
           htmReturnReason(HtmCacheFailure::NO_FAIL),
           htmTransactionUid(0),
           headerDelay(0),
           snoopDelay(0), payloadDelay(0), senderState(NULL)
    {
        flags.clear();
        if (req->hasPaddr()) {
            addr = req->getPaddr() & ~(_blkSize - 1);
            flags.set(VALID_ADDR);
            _isSecure = req->isSecure();
        }
        size = _blkSize;
        flags.set(VALID_SIZE);
    }
 
    Packet(const PacketPtr pkt, bool clear_flags, bool alloc_data)
        :  cmd(pkt->cmd), id(pkt->id), req(pkt->req),
           data(nullptr),
           addr(pkt->addr), _isSecure(pkt->_isSecure), size(pkt->size),
           bytesValid(pkt->bytesValid),
           _qosValue(pkt->qosValue()),
           htmReturnReason(HtmCacheFailure::NO_FAIL),
           htmTransactionUid(0),
           headerDelay(pkt->headerDelay),
           snoopDelay(0),
           payloadDelay(pkt->payloadDelay),
           senderState(pkt->senderState)
    {
        if (!clear_flags)
            flags.set(pkt->flags & COPY_FLAGS);
 
        flags.set(pkt->flags & (VALID_ADDR|VALID_SIZE));
 
        if (pkt->isHtmTransactional())
            setHtmTransactional(pkt->getHtmTransactionUid());
 
        if (pkt->htmTransactionFailedInCache()) {
            setHtmTransactionFailedInCache(
                pkt->getHtmTransactionFailedInCacheRC()
            );
        }
 
        // should we allocate space for data, or not, the express
        // snoops do not need to carry any data as they only serve to
        // co-ordinate state changes
        if (alloc_data) {
            // even if asked to allocate data, if the original packet
            // holds static data, then the sender will not be doing
            // any memcpy on receiving the response, thus we simply
            // carry the pointer forward
            if (pkt->flags.isSet(STATIC_DATA)) {
                data = pkt->data;
                flags.set(STATIC_DATA);
            } else {
                allocate();
            }
        }
    }
 
    static MemCmd
    makeReadCmd(const RequestPtr &req)
    {
        if (req->isHTMCmd()) {
            if (req->isHTMAbort())
                return MemCmd::HTMAbort;
            else
                return MemCmd::HTMReq;
        } else if (req->isLLSC())
            return MemCmd::LoadLockedReq;
        else if (req->isPrefetchEx())
            return MemCmd::SoftPFExReq;
        else if (req->isPrefetch())
            return MemCmd::SoftPFReq;
        else if (req->isLockedRMW())
            return MemCmd::LockedRMWReadReq;
        else
            return MemCmd::ReadReq;
    }
 
    static MemCmd
    makeWriteCmd(const RequestPtr &req)
    {
        if (req->isLLSC())
            return MemCmd::StoreCondReq;
        else if (req->isSwap() || req->isAtomic())
            return MemCmd::SwapReq;
        else if (req->isCacheInvalidate()) {
          return req->isCacheClean() ? MemCmd::CleanInvalidReq :
              MemCmd::InvalidateReq;
        } else if (req->isCacheClean()) {
            return MemCmd::CleanSharedReq;
        } else if (req->isLockedRMW()) {
            return MemCmd::LockedRMWWriteReq;
        } else
            return MemCmd::WriteReq;
    }
 
    static PacketPtr
    createRead(const RequestPtr &req)
    {
        return new Packet(req, makeReadCmd(req));
    }
 
    static PacketPtr
    createWrite(const RequestPtr &req)
    {
        return new Packet(req, makeWriteCmd(req));
    }
 
    ~Packet()
    {
        deleteData();
    }
 
    void
    makeResponse()
    {
        assert(needsResponse());
        assert(isRequest());
        cmd = cmd.responseCommand();
 
        // responses are never express, even if the snoop that
        // triggered them was
        flags.clear(EXPRESS_SNOOP);
    }
 
    void
    makeAtomicResponse()
    {
        makeResponse();
    }
 
    void
    makeTimingResponse()
    {
        makeResponse();
    }
 
    void
    setFunctionalResponseStatus(bool success)
    {
        if (!success) {
            if (isWrite()) {
                cmd = MemCmd::FunctionalWriteError;
            } else {
                cmd = MemCmd::FunctionalReadError;
            }
        }
    }
 
    void
    setSize(unsigned size)
    {
        assert(!flags.isSet(VALID_SIZE));
 
        this->size = size;
        flags.set(VALID_SIZE);
    }
 
    bool matchBlockAddr(const Addr addr, const bool is_secure,
                        const int blk_size) const;
 
    bool matchBlockAddr(const PacketPtr pkt, const int blk_size) const;
 
    bool matchAddr(const Addr addr, const bool is_secure) const;
 
    bool matchAddr(const PacketPtr pkt) const;
 
  public:
    template <typename T>
    void
    dataStatic(T *p)
    {
        assert(flags.noneSet(STATIC_DATA|DYNAMIC_DATA));
        data = (PacketDataPtr)p;
        flags.set(STATIC_DATA);
    }
 
    template <typename T>
    void
    dataStaticConst(const T *p)
    {
        assert(flags.noneSet(STATIC_DATA|DYNAMIC_DATA));
        data = const_cast<PacketDataPtr>(p);
        flags.set(STATIC_DATA);
    }
 
    template <typename T>
    void
    dataDynamic(T *p)
    {
        assert(flags.noneSet(STATIC_DATA|DYNAMIC_DATA));
        data = (PacketDataPtr)p;
        flags.set(DYNAMIC_DATA);
    }
 
    template <typename T>
    T*
    getPtr()
    {
        assert(flags.isSet(STATIC_DATA|DYNAMIC_DATA));
        assert(!isMaskedWrite());
        return (T*)data;
    }
 
    template <typename T>
    const T*
    getConstPtr() const
    {
        assert(flags.isSet(STATIC_DATA|DYNAMIC_DATA));
        return (const T*)data;
    }
 
    template <typename T>
    T getBE() const;
 
    template <typename T>
    T getLE() const;
 
    template <typename T>
    T get(ByteOrder endian) const;
 
    template <typename T>
    void setBE(T v);
 
    template <typename T>
    void setLE(T v);
 
    template <typename T>
    void set(T v, ByteOrder endian);
 
    uint64_t getUintX(ByteOrder endian) const;
 
    void setUintX(uint64_t w, ByteOrder endian);
 
    void
    setData(const uint8_t *p)
    {
        // we should never be copying data onto itself, which means we
        // must idenfity packets with static data, as they carry the
        // same pointer from source to destination and back
        assert(p != getPtr<uint8_t>() || flags.isSet(STATIC_DATA));
 
        if (p != getPtr<uint8_t>()) {
            // for packet with allocated dynamic data, we copy data from
            // one to the other, e.g. a forwarded response to a response
            std::memcpy(getPtr<uint8_t>(), p, getSize());
        }
    }
 
    void
    setDataFromBlock(const uint8_t *blk_data, int blkSize)
    {
        setData(blk_data + getOffset(blkSize));
    }
 
    void
    writeData(uint8_t *p) const
    {
        if (!isMaskedWrite()) {
            std::memcpy(p, getConstPtr<uint8_t>(), getSize());
        } else {
            assert(req->getByteEnable().size() == getSize());
            // Write only the enabled bytes
            const uint8_t *base = getConstPtr<uint8_t>();
            for (unsigned int i = 0; i < getSize(); i++) {
                if (req->getByteEnable()[i]) {
                    p[i] = *(base + i);
                }
                // Disabled bytes stay untouched
            }
        }
    }
 
    void
    writeDataToBlock(uint8_t *blk_data, int blkSize) const
    {
        writeData(blk_data + getOffset(blkSize));
    }
 
    void
    deleteData()
    {
        if (flags.isSet(DYNAMIC_DATA))
            delete [] data;
 
        flags.clear(STATIC_DATA|DYNAMIC_DATA);
        data = NULL;
    }
 
    void
    allocate()
    {
        // if either this command or the response command has a data
        // payload, actually allocate space
        if (hasData() || hasRespData()) {
            assert(flags.noneSet(STATIC_DATA|DYNAMIC_DATA));
            flags.set(DYNAMIC_DATA);
            data = new uint8_t[getSize()];
        }
    }
 
    template <typename T>
    T getRaw() const;
 
    template <typename T>
    void setRaw(T v);
 
  public:
    bool
    trySatisfyFunctional(PacketPtr other)
    {
        if (other->isMaskedWrite()) {
            // Do not forward data if overlapping with a masked write
            if (_isSecure == other->isSecure() &&
                getAddr() <= (other->getAddr() + other->getSize() - 1) &&
                other->getAddr() <= (getAddr() + getSize() - 1)) {
                warn("Trying to check against a masked write, skipping."
                     " (addr: 0x%x, other addr: 0x%x)", getAddr(),
                     other->getAddr());
            }
            return false;
        }
        // all packets that are carrying a payload should have a valid
        // data pointer
        return trySatisfyFunctional(other, other->getAddr(), other->isSecure(),
                                    other->getSize(),
                                    other->hasData() ?
                                    other->getPtr<uint8_t>() : NULL);
    }
 
    bool
    mustCheckAbove() const
    {
        return cmd == MemCmd::HardPFReq || isEviction();
    }
 
    bool
    isCleanEviction() const
    {
        return cmd == MemCmd::CleanEvict || cmd == MemCmd::WritebackClean;
    }
 
    bool
    isMaskedWrite() const
    {
        return (cmd == MemCmd::WriteReq && req->isMasked());
    }
 
    bool
    trySatisfyFunctional(Printable *obj, Addr base, bool is_secure, int size,
                         uint8_t *_data);
 
    void
    pushLabel(const std::string &lbl)
    {
        if (isPrint())
            safe_cast<PrintReqState*>(senderState)->pushLabel(lbl);
    }
 
    void
    popLabel()
    {
        if (isPrint())
            safe_cast<PrintReqState*>(senderState)->popLabel();
    }
 
    void print(std::ostream &o, int verbosity = 0,
               const std::string &prefix = "") const;
 
    std::string print() const;
 
    // hardware transactional memory
 
    void makeHtmTransactionalReqResponse(const HtmCacheFailure ret_code);
 
    void setHtmTransactional(uint64_t val);
 
    bool isHtmTransactional() const;
 
    uint64_t getHtmTransactionUid() const;
 
    void setHtmTransactionFailedInCache(const HtmCacheFailure ret_code);
 
    bool htmTransactionFailedInCache() const;
 
    HtmCacheFailure getHtmTransactionFailedInCacheRC() const;
};
 
} // namespace gem5
 
#endif //__MEM_PACKET_HH