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/*
* Copyright (c) 2012-2018 ARM Limited
* 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.
*
* Copyright (c) 2002-2005 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.
*
* Authors: Erik Hallnor
* Dave Greene
* Steve Reinhardt
* Ron Dreslinski
* Andreas Hansson
* Nikos Nikoleris
*/
/**
* @file
* Specifies a non-coherent cache. The non-coherent cache is expected
* to be located below the point of coherency. All valid blocks in the
* non-coherent cache can always be written to without any prior
* invalidations or snoops.
*/
#ifndef __MEM_CACHE_NONCOHERENT_CACHE_HH__
#define __MEM_CACHE_NONCOHERENT_CACHE_HH__
#include "base/logging.hh"
#include "base/types.hh"
#include "mem/cache/base.hh"
#include "mem/packet.hh"
class CacheBlk;
class MSHR;
struct NoncoherentCacheParams;
/**
* A non-coherent cache
*/
class NoncoherentCache : public BaseCache
{
protected:
bool access(PacketPtr pkt, CacheBlk *&blk, Cycles &lat,
PacketList &writebacks) override;
void handleTimingReqMiss(PacketPtr pkt, CacheBlk *blk,
Tick forward_time,
Tick request_time) override;
void recvTimingReq(PacketPtr pkt) override;
void doWritebacks(PacketList& writebacks,
Tick forward_time) override;
void doWritebacksAtomic(PacketList& writebacks) override;
void serviceMSHRTargets(MSHR *mshr, const PacketPtr pkt,
CacheBlk *blk, PacketList& writebacks) override;
void recvTimingResp(PacketPtr pkt) override;
void recvTimingSnoopReq(PacketPtr pkt) override {
panic("Unexpected timing snoop request %s", pkt->print());
}
void recvTimingSnoopResp(PacketPtr pkt) override {
panic("Unexpected timing snoop response %s", pkt->print());
}
Cycles handleAtomicReqMiss(PacketPtr pkt, CacheBlk *&blk,
PacketList &writebacks) override;
Tick recvAtomic(PacketPtr pkt) override;
Tick recvAtomicSnoop(PacketPtr pkt) override {
panic("Unexpected atomic snoop request %s", pkt->print());
}
void functionalAccess(PacketPtr pkt, bool from_cpu_side) override;
void satisfyRequest(PacketPtr pkt, CacheBlk *blk,
bool deferred_response = false,
bool pending_downgrade = false) override;
/*
* Creates a new packet with the request to be send to the memory
* below. The noncoherent cache is below the point of coherence
* and therefore all fills bring in writable, therefore the
* needs_writeble parameter is ignored.
*/
PacketPtr createMissPacket(PacketPtr cpu_pkt, CacheBlk *blk,
bool needs_writable,
bool is_whole_line_write) const override;
M5_NODISCARD PacketPtr evictBlock(CacheBlk *blk) override;
public:
NoncoherentCache(const NoncoherentCacheParams *p);
};
#endif // __MEM_CACHE_NONCOHERENTCACHE_HH__