gem5  v22.1.0.0
bridge.hh
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40 
47 #ifndef __MEM_BRIDGE_HH__
48 #define __MEM_BRIDGE_HH__
49 
50 #include <deque>
51 
52 #include "base/types.hh"
53 #include "mem/port.hh"
54 #include "params/Bridge.hh"
55 #include "sim/clocked_object.hh"
56 
57 namespace gem5
58 {
59 
73 class Bridge : public ClockedObject
74 {
75  protected:
76 
82  {
83 
84  public:
85 
86  const Tick tick;
87  const PacketPtr pkt;
88 
89  DeferredPacket(PacketPtr _pkt, Tick _tick) : tick(_tick), pkt(_pkt)
90  { }
91  };
92 
93  // Forward declaration to allow the response port to have a pointer
94  class BridgeRequestPort;
95 
103  {
104 
105  private:
106 
109 
114 
116  const Cycles delay;
117 
120 
128 
130  unsigned int outstandingResponses;
131 
133  bool retryReq;
134 
136  unsigned int respQueueLimit;
137 
142  std::unique_ptr<Packet> pendingDelete;
143 
149  bool respQueueFull() const;
150 
156  void trySendTiming();
157 
160 
161  public:
162 
174  BridgeResponsePort(const std::string& _name, Bridge& _bridge,
175  BridgeRequestPort& _memSidePort, Cycles _delay,
176  int _resp_limit, std::vector<AddrRange> _ranges);
177 
185  void schedTimingResp(PacketPtr pkt, Tick when);
186 
192  void retryStalledReq();
193 
194  protected:
195 
198  bool recvTimingReq(PacketPtr pkt);
199 
202  void recvRespRetry();
203 
207 
210  void recvFunctional(PacketPtr pkt);
211 
215  };
216 
217 
224  {
225 
226  private:
227 
230 
235 
237  const Cycles delay;
238 
246 
248  const unsigned int reqQueueLimit;
249 
255  void trySendTiming();
256 
259 
260  public:
261 
272  BridgeRequestPort(const std::string& _name, Bridge& _bridge,
273  BridgeResponsePort& _cpuSidePort, Cycles _delay,
274  int _req_limit);
275 
281  bool reqQueueFull() const;
282 
290  void schedTimingReq(PacketPtr pkt, Tick when);
291 
301 
302  protected:
303 
306  bool recvTimingResp(PacketPtr pkt);
307 
310  void recvReqRetry();
311  };
312 
315 
318 
319  public:
320 
321  Port &getPort(const std::string &if_name,
322  PortID idx=InvalidPortID) override;
323 
324  void init() override;
325 
326  typedef BridgeParams Params;
327 
328  Bridge(const Params &p);
329 };
330 
331 } // namespace gem5
332 
333 #endif //__MEM_BRIDGE_HH__
Defines global host-dependent types: Counter, Tick, and (indirectly) {int,uint}{8,...
Port on the side that forwards requests and receives responses.
Definition: bridge.hh:224
const Cycles delay
Minimum delay though this bridge.
Definition: bridge.hh:237
std::deque< DeferredPacket > transmitList
Request packet queue.
Definition: bridge.hh:245
bool recvTimingResp(PacketPtr pkt)
When receiving a timing request from the peer port, pass it to the bridge.
Definition: bridge.cc:125
BridgeResponsePort & cpuSidePort
The response port on the other side of the bridge.
Definition: bridge.hh:234
BridgeRequestPort(const std::string &_name, Bridge &_bridge, BridgeResponsePort &_cpuSidePort, Cycles _delay, int _req_limit)
Constructor for the BridgeRequestPort.
Definition: bridge.cc:69
bool trySatisfyFunctional(PacketPtr pkt)
Check a functional request against the packets in our request queue.
Definition: bridge.cc:375
bool reqQueueFull() const
Is this side blocked from accepting new request packets.
Definition: bridge.cc:119
const unsigned int reqQueueLimit
Max queue size for request packets.
Definition: bridge.hh:248
void schedTimingReq(PacketPtr pkt, Tick when)
Queue a request packet to be sent out later and also schedule a send if necessary.
Definition: bridge.cc:217
EventFunctionWrapper sendEvent
Send event for the request queue.
Definition: bridge.hh:258
void trySendTiming()
Handle send event, scheduled when the packet at the head of the outbound queue is ready to transmit (...
Definition: bridge.cc:248
void recvReqRetry()
When receiving a retry request from the peer port, pass it to the bridge.
Definition: bridge.cc:330
Bridge & bridge
The bridge to which this port belongs.
Definition: bridge.hh:229
The port on the side that receives requests and sends responses.
Definition: bridge.hh:103
bool respQueueFull() const
Is this side blocked from accepting new response packets.
Definition: bridge.cc:113
Tick recvAtomic(PacketPtr pkt)
When receiving a Atomic requestfrom the peer port, pass it to the bridge.
Definition: bridge.cc:342
unsigned int respQueueLimit
Max queue size for reserved responses.
Definition: bridge.hh:136
void recvRespRetry()
When receiving a retry request from the peer port, pass it to the bridge.
Definition: bridge.cc:336
const AddrRangeList ranges
Address ranges to pass through the bridge.
Definition: bridge.hh:119
unsigned int outstandingResponses
Counter to track the outstanding responses.
Definition: bridge.hh:130
bool retryReq
If we should send a retry when space becomes available.
Definition: bridge.hh:133
BridgeResponsePort(const std::string &_name, Bridge &_bridge, BridgeRequestPort &_memSidePort, Cycles _delay, int _resp_limit, std::vector< AddrRange > _ranges)
Constructor for the BridgeResponsePort.
Definition: bridge.cc:56
bool recvTimingReq(PacketPtr pkt)
When receiving a timing request from the peer port, pass it to the bridge.
Definition: bridge.cc:147
void schedTimingResp(PacketPtr pkt, Tick when)
Queue a response packet to be sent out later and also schedule a send if necessary.
Definition: bridge.cc:234
EventFunctionWrapper sendEvent
Send event for the response queue.
Definition: bridge.hh:159
const Cycles delay
Minimum request delay though this bridge.
Definition: bridge.hh:116
std::unique_ptr< Packet > pendingDelete
Upstream caches need this packet until true is returned, so hold it for deletion until a subsequent c...
Definition: bridge.hh:142
std::deque< DeferredPacket > transmitList
Response packet queue.
Definition: bridge.hh:127
void recvFunctional(PacketPtr pkt)
When receiving a Functional request from the peer port, pass it to the bridge.
Definition: bridge.cc:351
BridgeRequestPort & memSidePort
Request port on the other side of the bridge.
Definition: bridge.hh:113
AddrRangeList getAddrRanges() const
When receiving a address range request the peer port, pass it to the bridge.
Definition: bridge.cc:392
Bridge & bridge
The bridge to which this port belongs.
Definition: bridge.hh:108
void retryStalledReq()
Retry any stalled request that we have failed to accept at an earlier point in time.
Definition: bridge.cc:207
void trySendTiming()
Handle send event, scheduled when the packet at the head of the response queue is ready to transmit (...
Definition: bridge.cc:286
A deferred packet stores a packet along with its scheduled transmission time.
Definition: bridge.hh:82
DeferredPacket(PacketPtr _pkt, Tick _tick)
Definition: bridge.hh:89
const PacketPtr pkt
Definition: bridge.hh:87
A bridge is used to interface two different crossbars (or in general a memory-mapped requestor and re...
Definition: bridge.hh:74
BridgeRequestPort memSidePort
Request port of the bridge.
Definition: bridge.hh:317
Bridge(const Params &p)
Definition: bridge.cc:80
Port & getPort(const std::string &if_name, PortID idx=InvalidPortID) override
Get a port with a given name and index.
Definition: bridge.cc:90
BridgeParams Params
Definition: bridge.hh:326
BridgeResponsePort cpuSidePort
Response port of the bridge.
Definition: bridge.hh:314
void init() override
init() is called after all C++ SimObjects have been created and all ports are connected.
Definition: bridge.cc:102
The ClockedObject class extends the SimObject with a clock and accessor functions to relate ticks to ...
Cycles is a wrapper class for representing cycle counts, i.e.
Definition: types.hh:79
const std::string _name
Definition: named.hh:41
A Packet is used to encapsulate a transfer between two objects in the memory system (e....
Definition: packet.hh:294
Ports are used to interface objects to each other.
Definition: port.hh:62
A RequestPort is a specialisation of a Port, which implements the default protocol for the three diff...
Definition: port.hh:79
A ResponsePort is a specialization of a port.
Definition: port.hh:270
STL deque class.
Definition: stl.hh:44
STL vector class.
Definition: stl.hh:37
ClockedObject declaration and implementation.
Port Object Declaration.
Bitfield< 54 > p
Definition: pagetable.hh:70
Reference material can be found at the JEDEC website: UFS standard http://www.jedec....
const PortID InvalidPortID
Definition: types.hh:246
int16_t PortID
Port index/ID type, and a symbolic name for an invalid port id.
Definition: types.hh:245
uint64_t Tick
Tick count type.
Definition: types.hh:58

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