/*
- * Copyright (c) 2011-2012 ARM Limited
+ * Copyright (c) 2011-2012,2015,2017 ARM Limited
* All rights reserved
*
* The license below extends only to copyright in the software and shall
#ifndef __MEM_PORT_HH__
#define __MEM_PORT_HH__
-#include <list>
-
-#include "base/range.hh"
+#include "base/addr_range.hh"
+#include "mem/backdoor.hh"
#include "mem/packet.hh"
+#include "sim/port.hh"
+
+class MemObject;
+
+/** Forward declaration */
+class BaseSlavePort;
/**
- * This typedef is used to clean up getAddrRanges(). It's declared
- * outside the Port object since it's also used by some mem objects.
- * Eventually we should move this typedef to wherever Addr is
- * defined.
+ * A BaseMasterPort is a protocol-agnostic master port, responsible
+ * only for the structural connection to a slave port. The final
+ * master port that inherits from the base class must override the
+ * bind member function for the specific slave port class.
*/
+class BaseMasterPort : public Port
+{
-typedef std::list<Range<Addr> > AddrRangeList;
-typedef std::list<Range<Addr> >::iterator AddrRangeIter;
+ protected:
-class MemObject;
+ BaseSlavePort* _baseSlavePort;
+
+ BaseMasterPort(const std::string& name, PortID id=InvalidPortID);
+ virtual ~BaseMasterPort();
+
+ public:
+
+ BaseSlavePort& getSlavePort() const;
+
+};
/**
- * Ports are used to interface memory objects to each other. A port is
- * either a master or a slave and the connected peer is always of the
- * opposite role.
- *
- * Each port has a name and an owner, and enables three basic types of
- * accesses to the peer port: sendFunctional, sendAtomic and
- * sendTiming.
+ * A BaseSlavePort is a protocol-agnostic slave port, responsible
+ * only for the structural connection to a master port.
*/
-class Port
+class BaseSlavePort : public Port
{
- private:
+ protected:
- /** Descriptive name (for DPRINTF output) */
- std::string portName;
+ BaseMasterPort* _baseMasterPort;
- protected:
+ BaseSlavePort(const std::string& name, PortID id=InvalidPortID);
+ virtual ~BaseSlavePort();
- /** A pointer to the peer port. */
- Port* peer;
+ public:
- /** A reference to the MemObject that owns this port. */
- MemObject& owner;
+ BaseMasterPort& getMasterPort() const;
- /**
- * Abstract base class for ports
- *
- * @param _name Port name including the owners name
- * @param _owner The MemObject that is the structural owner of this port
- */
- Port(const std::string& _name, MemObject& _owner);
+};
- /**
- * Virtual destructor due to inheritance.
- */
- virtual ~Port();
+/** Forward declaration */
+class SlavePort;
- public:
+/**
+ * A MasterPort is a specialisation of a BaseMasterPort, which
+ * implements the default protocol for the three different level of
+ * transport functions. In addition to the basic functionality of
+ * sending packets, it also has functions to receive range changes or
+ * determine if the port is snooping or not.
+ */
+class MasterPort : public BaseMasterPort
+{
- /** Return port name (for DPRINTF). */
- const std::string name() const { return portName; }
+ friend class SlavePort;
- protected:
+ private:
- /** These functions are protected because they should only be
- * called by a peer port, never directly by any outside object. */
+ SlavePort* _slavePort;
- /** Called to recive a timing call from the peer port. */
- virtual bool recvTiming(PacketPtr pkt) = 0;
+ protected:
- /** Called to recive a atomic call from the peer port. */
- virtual Tick recvAtomic(PacketPtr pkt) = 0;
+ MemObject& owner;
- /** Called to recive a functional call from the peer port. */
- virtual void recvFunctional(PacketPtr pkt) = 0;
+ public:
+
+ MasterPort(const std::string& name, MemObject* _owner,
+ PortID id=InvalidPortID);
+ virtual ~MasterPort();
/**
- * Called by a peer port if sendTiming was unsuccesful, and had to
- * wait.
+ * Bind this master port to a slave port. This also does the
+ * mirror action and binds the slave port to the master port.
*/
- virtual void recvRetry() = 0;
+ void bind(Port &peer) override;
- public:
+ /**
+ * Unbind this master port and the associated slave port.
+ */
+ void unbind() override;
/**
- * Attempt to send a timing packet to the peer port by calling its
- * receive function. If the send does not succeed, as indicated by
- * the return value, then the sender must wait for a recvRetry at
- * which point it can re-issue a sendTiming.
+ * Send an atomic request packet, where the data is moved and the
+ * state is updated in zero time, without interleaving with other
+ * memory accesses.
*
* @param pkt Packet to send.
*
- * @return If the send was succesful or not.
- */
- bool sendTiming(PacketPtr pkt) { return peer->recvTiming(pkt); }
-
- /**
- * Send a retry to a peer port that previously attempted a sendTiming
- * which was unsuccessful.
+ * @return Estimated latency of access.
*/
- void sendRetry() { return peer->recvRetry(); }
+ Tick sendAtomic(PacketPtr pkt);
/**
- * Send an atomic packet, where the data is moved and the state
- * is updated in zero time, without interleaving with other
- * memory accesses.
+ * Send an atomic request packet like above, but also request a backdoor
+ * to the data being accessed.
*
* @param pkt Packet to send.
+ * @param backdoor Can be set to a back door pointer by the target to let
+ * caller have direct access to the requested data.
*
* @return Estimated latency of access.
*/
- Tick sendAtomic(PacketPtr pkt) { return peer->recvAtomic(pkt); }
+ Tick sendAtomicBackdoor(PacketPtr pkt, MemBackdoorPtr &backdoor);
/**
- * Send a functional packet, where the data is instantly updated
- * everywhere in the memory system, without affecting the current
- * state of any block or moving the block.
+ * Send a functional request packet, where the data is instantly
+ * updated everywhere in the memory system, without affecting the
+ * current state of any block or moving the block.
*
* @param pkt Packet to send.
*/
- void sendFunctional(PacketPtr pkt) { return peer->recvFunctional(pkt); }
+ void sendFunctional(PacketPtr pkt);
-};
-
-/** Forward declaration */
-class SlavePort;
-
-/**
- * A MasterPort is a specialisation of a port. In addition to the
- * basic functionality of sending packets to its slave peer, it also
- * has functions specific to a master, e.g. to receive range changes
- * or determine if the port is snooping or not.
- */
-class MasterPort : public Port
-{
-
- private:
-
- SlavePort* _slavePort;
-
- public:
+ /**
+ * Attempt to send a timing request to the slave port by calling
+ * its corresponding receive function. If the send does not
+ * succeed, as indicated by the return value, then the sender must
+ * wait for a recvReqRetry at which point it can re-issue a
+ * sendTimingReq.
+ *
+ * @param pkt Packet to send.
+ *
+ * @return If the send was succesful or not.
+ */
+ bool sendTimingReq(PacketPtr pkt);
- MasterPort(const std::string& name, MemObject* owner);
- virtual ~MasterPort();
+ /**
+ * Check if the slave can handle a timing request.
+ *
+ * If the send cannot be handled at the moment, as indicated by
+ * the return value, then the sender will receive a recvReqRetry
+ * at which point it can re-issue a sendTimingReq.
+ *
+ * @param pkt Packet to send.
+ *
+ * @return If the send was succesful or not.
+ */
+ bool tryTiming(PacketPtr pkt) const;
- void bind(SlavePort& slave_port);
- SlavePort& getSlavePort() const;
- bool isConnected() const;
+ /**
+ * Attempt to send a timing snoop response packet to the slave
+ * port by calling its corresponding receive function. If the send
+ * does not succeed, as indicated by the return value, then the
+ * sender must wait for a recvRetrySnoop at which point it can
+ * re-issue a sendTimingSnoopResp.
+ *
+ * @param pkt Packet to send.
+ */
+ bool sendTimingSnoopResp(PacketPtr pkt);
/**
- * Called to receive an address range change from the peer slave
- * port. the default implementation ignored the change and does
- * nothing. Override this function in a derived class if the owner
- * needs to be aware of he laesddress ranges, e.g. in an
- * interconnect component like a bus.
+ * Send a retry to the slave port that previously attempted a
+ * sendTimingResp to this master port and failed. Note that this
+ * is virtual so that the "fake" snoop response port in the
+ * coherent crossbar can override the behaviour.
*/
- virtual void recvRangeChange() { }
+ virtual void sendRetryResp();
/**
* Determine if this master port is snooping or not. The default
virtual bool isSnooping() const { return false; }
/**
- * Called by a peer port in order to determine the block size of
- * the owner of this port.
+ * Get the address ranges of the connected slave port.
*/
- virtual unsigned deviceBlockSize() const { return 0; }
-
- /** Called by the associated device if it wishes to find out the blocksize
- of the device on attached to the peer port.
- */
- unsigned peerBlockSize() const;
+ AddrRangeList getAddrRanges() const;
/** Inject a PrintReq for the given address to print the state of
* that address throughout the memory system. For debugging.
*/
void printAddr(Addr a);
+
+ protected:
+
+ /**
+ * Receive an atomic snoop request packet from the slave port.
+ */
+ virtual Tick recvAtomicSnoop(PacketPtr pkt)
+ {
+ panic("%s was not expecting an atomic snoop request\n", name());
+ return 0;
+ }
+
+ /**
+ * Receive a functional snoop request packet from the slave port.
+ */
+ virtual void recvFunctionalSnoop(PacketPtr pkt)
+ {
+ panic("%s was not expecting a functional snoop request\n", name());
+ }
+
+ /**
+ * Receive a timing response from the slave port.
+ */
+ virtual bool recvTimingResp(PacketPtr pkt) = 0;
+
+ /**
+ * Receive a timing snoop request from the slave port.
+ */
+ virtual void recvTimingSnoopReq(PacketPtr pkt)
+ {
+ panic("%s was not expecting a timing snoop request\n", name());
+ }
+
+ /**
+ * Called by the slave port if sendTimingReq was called on this
+ * master port (causing recvTimingReq to be called on the slave
+ * port) and was unsuccesful.
+ */
+ virtual void recvReqRetry() = 0;
+
+ /**
+ * Called by the slave port if sendTimingSnoopResp was called on this
+ * master port (causing recvTimingSnoopResp to be called on the slave
+ * port) and was unsuccesful.
+ */
+ virtual void recvRetrySnoopResp()
+ {
+ panic("%s was not expecting a snoop retry\n", name());
+ }
+
+ /**
+ * Called to receive an address range change from the peer slave
+ * port. The default implementation ignores the change and does
+ * nothing. Override this function in a derived class if the owner
+ * needs to be aware of the address ranges, e.g. in an
+ * interconnect component like a bus.
+ */
+ virtual void recvRangeChange() { }
};
/**
* has functions specific to a slave, e.g. to send range changes
* and get the address ranges that the port responds to.
*/
-class SlavePort : public Port
+class SlavePort : public BaseSlavePort
{
+ friend class MasterPort;
+
private:
MasterPort* _masterPort;
+ bool defaultBackdoorWarned;
+
+ protected:
+
+ MemObject& owner;
public:
- SlavePort(const std::string& name, MemObject* owner);
+ SlavePort(const std::string& name, MemObject* _owner,
+ PortID id=InvalidPortID);
virtual ~SlavePort();
- void bind(MasterPort& master_port);
- MasterPort& getMasterPort() const;
- bool isConnected() const;
+ /**
+ * Send an atomic snoop request packet, where the data is moved
+ * and the state is updated in zero time, without interleaving
+ * with other memory accesses.
+ *
+ * @param pkt Snoop packet to send.
+ *
+ * @return Estimated latency of access.
+ */
+ Tick sendAtomicSnoop(PacketPtr pkt);
/**
- * Called by a peer port in order to determine the block size of
- * the owner of this port.
+ * Send a functional snoop request packet, where the data is
+ * instantly updated everywhere in the memory system, without
+ * affecting the current state of any block or moving the block.
+ *
+ * @param pkt Snoop packet to send.
*/
- virtual unsigned deviceBlockSize() const { return 0; }
+ void sendFunctionalSnoop(PacketPtr pkt);
- /** Called by the associated device if it wishes to find out the blocksize
- of the device on attached to the peer port.
+ /**
+ * Attempt to send a timing response to the master port by calling
+ * its corresponding receive function. If the send does not
+ * succeed, as indicated by the return value, then the sender must
+ * wait for a recvRespRetry at which point it can re-issue a
+ * sendTimingResp.
+ *
+ * @param pkt Packet to send.
+ *
+ * @return If the send was succesful or not.
*/
- unsigned peerBlockSize() const;
+ bool sendTimingResp(PacketPtr pkt);
+
+ /**
+ * Attempt to send a timing snoop request packet to the master port
+ * by calling its corresponding receive function. Snoop requests
+ * always succeed and hence no return value is needed.
+ *
+ * @param pkt Packet to send.
+ */
+ void sendTimingSnoopReq(PacketPtr pkt);
+
+ /**
+ * Send a retry to the master port that previously attempted a
+ * sendTimingReq to this slave port and failed.
+ */
+ void sendRetryReq();
+
+ /**
+ * Send a retry to the master port that previously attempted a
+ * sendTimingSnoopResp to this slave port and failed.
+ */
+ void sendRetrySnoopResp();
+
+ /**
+ * Find out if the peer master port is snooping or not.
+ *
+ * @return true if the peer master port is snooping
+ */
+ bool isSnooping() const { return _masterPort->isSnooping(); }
/**
* Called by the owner to send a range change
*/
- void sendRangeChange() const { _masterPort->recvRangeChange(); }
+ void sendRangeChange() const {
+ if (!_masterPort)
+ fatal("%s cannot sendRangeChange() without master port", name());
+ _masterPort->recvRangeChange();
+ }
/**
* Get a list of the non-overlapping address ranges the owner is
*
* @return a list of ranges responded to
*/
- virtual AddrRangeList getAddrRanges() = 0;
+ virtual AddrRangeList getAddrRanges() const = 0;
+
+ /**
+ * We let the master port do the work, so these don't do anything.
+ */
+ void unbind() override {}
+ void bind(Port &peer) override {}
+
+ protected:
+
+ /**
+ * Called by the master port to unbind. Should never be called
+ * directly.
+ */
+ void slaveUnbind();
+
+ /**
+ * Called by the master port to bind. Should never be called
+ * directly.
+ */
+ void slaveBind(MasterPort& master_port);
+
+ /**
+ * Receive an atomic request packet from the master port.
+ */
+ virtual Tick recvAtomic(PacketPtr pkt) = 0;
+
+ /**
+ * Receive an atomic request packet from the master port, and optionally
+ * provide a backdoor to the data being accessed.
+ */
+ virtual Tick recvAtomicBackdoor(PacketPtr pkt, MemBackdoorPtr &backdoor);
+
+ /**
+ * Receive a functional request packet from the master port.
+ */
+ virtual void recvFunctional(PacketPtr pkt) = 0;
+
+ /**
+ * Receive a timing request from the master port.
+ */
+ virtual bool recvTimingReq(PacketPtr pkt) = 0;
+
+ /**
+ * Availability request from the master port.
+ */
+ virtual bool tryTiming(PacketPtr pkt) {
+ panic("%s was not expecting a %s\n", name(), __func__);
+ }
+
+ /**
+ * Receive a timing snoop response from the master port.
+ */
+ virtual bool recvTimingSnoopResp(PacketPtr pkt)
+ {
+ panic("%s was not expecting a timing snoop response\n", name());
+ }
+
+ /**
+ * Called by the master port if sendTimingResp was called on this
+ * slave port (causing recvTimingResp to be called on the master
+ * port) and was unsuccesful.
+ */
+ virtual void recvRespRetry() = 0;
+
};
#endif //__MEM_PORT_HH__