diff options
Diffstat (limited to 'src/mem/bus.hh')
| -rw-r--r-- | src/mem/bus.hh | 135 |
1 files changed, 111 insertions, 24 deletions
diff --git a/src/mem/bus.hh b/src/mem/bus.hh index e79e9df9e..8a0676353 100644 --- a/src/mem/bus.hh +++ b/src/mem/bus.hh @@ -91,25 +91,35 @@ class Bus : public MemObject protected: - /** When reciving a timing request from the peer port (at id), - pass it to the bus. */ + /** + * When receiving a timing request, pass it to the bus. + */ virtual bool recvTiming(PacketPtr pkt) { pkt->setSrc(id); return bus->recvTiming(pkt); } - /** When reciving a Atomic requestfrom the peer port (at id), - pass it to the bus. */ + /** + * When receiving a timing snoop response, pass it to the bus. + */ + virtual bool recvTimingSnoop(PacketPtr pkt) + { pkt->setSrc(id); return bus->recvTimingSnoop(pkt); } + + /** + * When receiving an atomic request, pass it to the bus. + */ virtual Tick recvAtomic(PacketPtr pkt) { pkt->setSrc(id); return bus->recvAtomic(pkt); } - /** When reciving a Functional requestfrom the peer port (at id), - pass it to the bus. */ + /** + * When receiving a functional request, pass it to the bus. + */ virtual void recvFunctional(PacketPtr pkt) { pkt->setSrc(id); bus->recvFunctional(pkt); } - /** When reciving a retry from the peer port (at id), - pass it to the bus. */ + /** + * When receiving a retry, pass it to the bus. + */ virtual void recvRetry() - { bus->recvRetry(id); } + { panic("Bus slave ports always succeed and should never retry.\n"); } // This should return all the 'owned' addresses that are // downstream from this bus, yes? That is, the union of all @@ -160,20 +170,29 @@ class Bus : public MemObject protected: - /** When reciving a timing request from the peer port (at id), - pass it to the bus. */ + /** + * When receiving a timing response, pass it to the bus. + */ virtual bool recvTiming(PacketPtr pkt) { pkt->setSrc(id); return bus->recvTiming(pkt); } - /** When reciving a Atomic requestfrom the peer port (at id), - pass it to the bus. */ - virtual Tick recvAtomic(PacketPtr pkt) - { pkt->setSrc(id); return bus->recvAtomic(pkt); } + /** + * When receiving a timing snoop request, pass it to the bus. + */ + virtual bool recvTimingSnoop(PacketPtr pkt) + { pkt->setSrc(id); return bus->recvTimingSnoop(pkt); } - /** When reciving a Functional requestfrom the peer port (at id), - pass it to the bus. */ - virtual void recvFunctional(PacketPtr pkt) - { pkt->setSrc(id); bus->recvFunctional(pkt); } + /** + * When receiving an atomic snoop request, pass it to the bus. + */ + virtual Tick recvAtomicSnoop(PacketPtr pkt) + { pkt->setSrc(id); return bus->recvAtomicSnoop(pkt); } + + /** + * When receiving a functional snoop request, pass it to the bus. + */ + virtual void recvFunctionalSnoop(PacketPtr pkt) + { pkt->setSrc(id); bus->recvFunctionalSnoop(pkt); } /** When reciving a range change from the peer port (at id), pass it to the bus. */ @@ -212,18 +231,91 @@ class Bus : public MemObject typedef std::vector<BusSlavePort*>::iterator SnoopIter; std::vector<BusSlavePort*> snoopPorts; + /** + * Store the outstanding requests so we can determine which ones + * we generated and which ones were merely forwarded. This is used + * in the coherent bus when coherency responses come back. + */ + std::set<RequestPtr> outstandingReq; + /** Function called by the port when the bus is recieving a Timing transaction.*/ bool recvTiming(PacketPtr pkt); + /** Function called by the port when the bus is recieving a timing + snoop transaction.*/ + bool recvTimingSnoop(PacketPtr pkt); + + /** + * Forward a timing packet to our snoopers, potentially excluding + * one of the connected coherent masters to avoid sending a packet + * back to where it came from. + * + * @param pkt Packet to forward + * @param exclude_slave_port_id Id of slave port to exclude + */ + void forwardTiming(PacketPtr pkt, int exclude_slave_port_id); + + /** + * Determine if the bus is to be considered occupied when being + * presented with a packet from a specific port. If so, the port + * in question is also added to the retry list. + * + * @param pkt Incoming packet + * @param port Source port on the bus presenting the packet + * + * @return True if the bus is to be considered occupied + */ + bool isOccupied(PacketPtr pkt, Port* port); + + /** + * Deal with a destination port accepting a packet by potentially + * removing the source port from the retry list (if retrying) and + * occupying the bus accordingly. + * + * @param busy_time Time to spend as a result of a successful send + */ + void succeededTiming(Tick busy_time); + /** Function called by the port when the bus is recieving a Atomic transaction.*/ Tick recvAtomic(PacketPtr pkt); + /** Function called by the port when the bus is recieving an + atomic snoop transaction.*/ + Tick recvAtomicSnoop(PacketPtr pkt); + + /** + * Forward an atomic packet to our snoopers, potentially excluding + * one of the connected coherent masters to avoid sending a packet + * back to where it came from. + * + * @param pkt Packet to forward + * @param exclude_slave_port_id Id of slave port to exclude + * + * @return a pair containing the snoop response and snoop latency + */ + std::pair<MemCmd, Tick> forwardAtomic(PacketPtr pkt, + int exclude_slave_port_id); + /** Function called by the port when the bus is recieving a Functional transaction.*/ void recvFunctional(PacketPtr pkt); + /** Function called by the port when the bus is recieving a functional + snoop transaction.*/ + void recvFunctionalSnoop(PacketPtr pkt); + + /** + * Forward a functional packet to our snoopers, potentially + * excluding one of the connected coherent masters to avoid + * sending a packet back to where it came from. + * + * @param pkt Packet to forward + * @param exclude_slave_port_id Id of slave port to exclude + */ + void forwardFunctional(PacketPtr pkt, int exclude_slave_port_id); + /** Timing function called by port when it is once again able to process * requests. */ void recvRetry(int id); @@ -345,11 +437,6 @@ class Bus : public MemObject bool inRetry; std::set<int> inRecvRangeChange; - // keep track of the number of master ports (not counting the - // default master) since we need this as an offset into the - // interfaces vector - unsigned int nbrMasterPorts; - /** The master and slave ports of the bus */ std::vector<BusSlavePort*> slavePorts; std::vector<BusMasterPort*> masterPorts; |