gem5  v21.1.0.2
tport.cc
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40 
41 #include "mem/tport.hh"
42 #include "sim/sim_object.hh"
43 
44 namespace gem5
45 {
46 
47 SimpleTimingPort::SimpleTimingPort(const std::string& _name,
48  SimObject* _owner) :
49  QueuedResponsePort(_name, _owner, queueImpl), queueImpl(*_owner, *this)
50 {
51 }
52 
53 void
55 {
56  if (!respQueue.trySatisfyFunctional(pkt)) {
57  // do an atomic access and throw away the returned latency
58  recvAtomic(pkt);
59  }
60 }
61 
62 bool
64 {
65  // the SimpleTimingPort should not be used anywhere where there is
66  // a need to deal with snoop responses and their flow control
67  // requirements
68  if (pkt->cacheResponding())
69  panic("SimpleTimingPort should never see packets with the "
70  "cacheResponding flag set\n");
71 
72  bool needsResponse = pkt->needsResponse();
73  Tick latency = recvAtomic(pkt);
74  // turn packet around to go back to requestor if response expected
75  if (needsResponse) {
76  // recvAtomic() should already have turned packet into
77  // atomic response
78  assert(pkt->isResponse());
79  schedTimingResp(pkt, curTick() + latency);
80  } else {
81  // queue the packet for deletion
82  pendingDelete.reset(pkt);
83  }
84 
85  return true;
86 }
87 
88 } // namespace gem5
gem5::curTick
Tick curTick()
The universal simulation clock.
Definition: cur_tick.hh:46
gem5::SimpleTimingPort::recvFunctional
void recvFunctional(PacketPtr pkt)
Implemented using recvAtomic().
Definition: tport.cc:54
gem5::Packet::cacheResponding
bool cacheResponding() const
Definition: packet.hh:646
gem5::SimpleTimingPort::pendingDelete
std::unique_ptr< Packet > pendingDelete
Upstream caches need this packet until true is returned, so hold it for deletion until a subsequent c...
Definition: tport.hh:89
gem5::QueuedResponsePort::respQueue
RespPacketQueue & respQueue
Packet queue used to store outgoing responses.
Definition: qport.hh:67
gem5::PacketQueue::trySatisfyFunctional
bool trySatisfyFunctional(PacketPtr pkt)
Check the list of buffered packets against the supplied functional request.
Definition: packet_queue.cc:87
gem5::SimpleTimingPort::SimpleTimingPort
SimpleTimingPort(const std::string &name, SimObject *owner)
Create a new SimpleTimingPort that relies on a packet queue to hold responses, and implements recvTim...
Definition: tport.cc:47
sim_object.hh
gem5::QueuedResponsePort
A queued port is a port that has an infinite queue for outgoing packets and thus decouples the module...
Definition: qport.hh:61
gem5::Packet
A Packet is used to encapsulate a transfer between two objects in the memory system (e....
Definition: packet.hh:283
gem5::Tick
uint64_t Tick
Tick count type.
Definition: types.hh:58
gem5::SimObject
Abstract superclass for simulation objects.
Definition: sim_object.hh:146
gem5::Packet::needsResponse
bool needsResponse() const
Definition: packet.hh:597
tport.hh
gem5::SimpleTimingPort::recvAtomic
virtual Tick recvAtomic(PacketPtr pkt)=0
Receive an atomic request packet from the peer.
gem5::QueuedResponsePort::schedTimingResp
void schedTimingResp(PacketPtr pkt, Tick when)
Schedule the sending of a timing response.
Definition: qport.hh:93
gem5
Reference material can be found at the JEDEC website: UFS standard http://www.jedec....
Definition: decoder.cc:40
gem5::Packet::isResponse
bool isResponse() const
Definition: packet.hh:587
panic
#define panic(...)
This implements a cprintf based panic() function.
Definition: logging.hh:177
gem5::SimpleTimingPort::recvTimingReq
bool recvTimingReq(PacketPtr pkt)
Implemented using recvAtomic().
Definition: tport.cc:63

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