/*
- * 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"
-
-/**
- * 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.
- */
-
-typedef std::list<Range<Addr> > AddrRangeList;
-typedef std::list<Range<Addr> >::iterator AddrRangeIter;
-typedef std::list<Range<Addr> >::const_iterator AddrRangeConstIter;
+#include "sim/port.hh"
class MemObject;
+/** Forward declaration */
+class BaseSlavePort;
+
/**
- * 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, an owner, and an identifier.
+ * 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 Port
+class BaseMasterPort : public Port
{
- private:
+ protected:
- /** Descriptive name (for DPRINTF output) */
- std::string portName;
+ BaseSlavePort* _baseSlavePort;
- protected:
+ BaseMasterPort(const std::string& name, PortID id=InvalidPortID);
+ virtual ~BaseMasterPort();
- /**
- * A numeric identifier to distinguish ports in a vector, and set
- * to InvalidPortID in case this port is not part of a vector.
- */
- const PortID id;
+ public:
- /** A reference to the MemObject that owns this port. */
- MemObject& owner;
+ BaseSlavePort& getSlavePort() 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
- * @param _id A port identifier for vector ports
- */
- Port(const std::string& _name, MemObject& _owner, PortID _id);
+};
- /**
- * Virtual destructor due to inheritance.
- */
- virtual ~Port();
+/**
+ * A BaseSlavePort is a protocol-agnostic slave port, responsible
+ * only for the structural connection to a master port.
+ */
+class BaseSlavePort : public Port
+{
- public:
+ protected:
+
+ BaseMasterPort* _baseMasterPort;
- /** Return port name (for DPRINTF). */
- const std::string name() const { return portName; }
+ BaseSlavePort(const std::string& name, PortID id=InvalidPortID);
+ virtual ~BaseSlavePort();
- /** Get the port id. */
- PortID getId() const { return id; }
+ public:
+
+ BaseMasterPort& getMasterPort() const;
};
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.
+ * 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 Port
+class MasterPort : public BaseMasterPort
{
friend class SlavePort;
SlavePort* _slavePort;
+ protected:
+
+ MemObject& owner;
+
public:
- MasterPort(const std::string& name, MemObject* owner,
- PortID id = InvalidPortID);
+ MasterPort(const std::string& name, MemObject* _owner,
+ PortID id=InvalidPortID);
virtual ~MasterPort();
- void bind(SlavePort& slave_port);
- SlavePort& getSlavePort() const;
- bool isConnected() const;
+ /**
+ * Bind this master port to a slave port. This also does the
+ * mirror action and binds the slave port to the master port.
+ */
+ void bind(Port &peer) override;
+
+ /**
+ * Unbind this master port and the associated slave port.
+ */
+ void unbind() override;
/**
* Send an atomic request packet, where the data is moved and the
*/
Tick sendAtomic(PacketPtr pkt);
+ /**
+ * 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 sendAtomicBackdoor(PacketPtr pkt, MemBackdoorPtr &backdoor);
+
/**
* Send a functional request packet, where the data is instantly
* updated everywhere in the memory system, without affecting the
* 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 recvRetry at which point it can re-issue a
+ * wait for a recvReqRetry at which point it can re-issue a
* sendTimingReq.
*
* @param pkt Packet to send.
*/
bool sendTimingReq(PacketPtr pkt);
+ /**
+ * 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;
+
/**
* 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 recvRetry at which point it can re-issue
- * a sendTimingSnoopResp.
+ * sender must wait for a recvRetrySnoop at which point it can
+ * re-issue a sendTimingSnoopResp.
*
* @param pkt Packet to send.
*/
/**
* Send a retry to the slave port that previously attempted a
- * sendTimingResp to this master port and failed.
+ * 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.
*/
- void sendRetry();
+ 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.
- */
- 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;
-
/**
* Get the address ranges of the connected slave port.
*/
}
/**
- * Called by the slave port if sendTimingReq or
- * sendTimingSnoopResp was called on this master port (causing
- * recvTimingReq and recvTimingSnoopResp to be called on the
- * slave port) and was unsuccesful.
+ * 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 recvRetry() = 0;
+ 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 ignored the change and does
+ * 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 he laesddress ranges, e.g. in an
+ * 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,
- PortID id = InvalidPortID);
+ 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
* 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 recvRetry at which point it can re-issue a
+ * wait for a recvRespRetry at which point it can re-issue a
* sendTimingResp.
*
* @param pkt Packet to send.
/**
* Send a retry to the master port that previously attempted a
- * sendTimingReq or sendTimingSnoopResp to this slave port and
- * failed.
+ * sendTimingReq to this slave port and failed.
*/
- void sendRetry();
+ void sendRetryReq();
/**
- * Called by a peer port in order to determine the block size of
- * the owner of this port.
+ * Send a retry to the master port that previously attempted a
+ * sendTimingSnoopResp to this slave port and failed.
*/
- 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;
+ void sendRetrySnoopResp();
/**
* Find out if the peer master port is snooping or not.
/**
* 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
*/
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 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.
*/
* slave port (causing recvTimingResp to be called on the master
* port) and was unsuccesful.
*/
- virtual void recvRetry() = 0;
+ virtual void recvRespRetry() = 0;
};