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Diffstat (limited to 'src/mem/external_slave.hh')
| -rw-r--r-- | src/mem/external_slave.hh | 142 |
1 files changed, 142 insertions, 0 deletions
diff --git a/src/mem/external_slave.hh b/src/mem/external_slave.hh new file mode 100644 index 000000000..d1782237c --- /dev/null +++ b/src/mem/external_slave.hh @@ -0,0 +1,142 @@ +/* + * Copyright (c) 2012-2014 ARM Limited + * All rights reserved + * + * The license below extends only to copyright in the software and shall + * not be construed as granting a license to any other intellectual + * property including but not limited to intellectual property relating + * to a hardware implementation of the functionality of the software + * licensed hereunder. You may use the software subject to the license + * terms below provided that you ensure that this notice is replicated + * unmodified and in its entirety in all distributions of the software, + * modified or unmodified, in source code or in binary form. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions are + * met: redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer; + * redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution; + * neither the name of the copyright holders nor the names of its + * contributors may be used to endorse or promote products derived from + * this software without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS + * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT + * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR + * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT + * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, + * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT + * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, + * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY + * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT + * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE + * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + * + * Authors: Andrew Bardsley + */ + +/** + * @file + * + * ExternalSlave is a memory object representing a binding from + * a gem5 master to a slave port in a system external to gem5. + * + * During initialisation, a `handler' for the port type specified in the + * port's port_type parameter is found from the registered port handlers + * provided with registerHandler. Once a handler is found, it is passed the + * port_data parameter of the port which can be used to identify the external + * port which is to be bound to. A port handler will usually construct a + * bridge object in the external system to accomodate the port-to-port + * mapping but this bridge is not exposed to gem5 other than be the + * presentation of the SlavePort which can be bound. + * + * The external port must provide a gem5 SlavePort interface (with the + * exception of getAddrRanges which is provided by the ExternalSlave + * object). + */ + +#ifndef __MEM_EXTERNAL_SLAVE__ +#define __MEM_EXTERNAL_SLAVE__ + +#include "mem/mem_object.hh" +#include "params/ExternalSlave.hh" + +class ExternalSlave : public MemObject +{ + public: + /** Derive from this class to create an external port interface */ + class Port : public SlavePort + { + protected: + ExternalSlave &owner; + + public: + Port(const std::string &name_, + ExternalSlave &owner_) : + SlavePort(name_, &owner_), owner(owner_) + { } + + ~Port() { } + + /** Any or all of recv... can be overloaded to provide the port's + * functionality */ + + AddrRangeList getAddrRanges() const; + }; + + /* Handlers are specific to *types* of port not specific port + * instantiations. A handler will typically build a bridge to the + * external port from gem5 and provide gem5 with a SlavePort that can be + * bound to for each call to Handler::getExternalPort.*/ + class Handler + { + public: + /** Create or find an external port which can be bound. Returns + * NULL on failure */ + virtual Port *getExternalPort( + const std::string &name, ExternalSlave &owner, + const std::string &port_data) = 0; + }; + + protected: + /** The peer port for the gem5 port "port" */ + Port *externalPort; + + /** Name of the bound port. This will be name() + ".port" */ + std::string portName; + + /** Key to select a port handler */ + std::string portType; + + /** Handler-specific port configuration */ + std::string portData; + + /** The Range of addresses supported by the devices on the external + * side of this port */ + AddrRangeList addrRanges; + + /** Registered handlers. Handlers are chosen using the port_type + * parameter on ExternalSlaves. port_types form a global namespace + * across the simulation and so handlers are registered into a global + * structure */ + static std::map<std::string, Handler *> portHandlers; + + public: + ExternalSlave(ExternalSlaveParams *params); + + /** SlavePort interface. Responds only to port "port" */ + BaseSlavePort &getSlavePort(const std::string &if_name, + PortID idx = InvalidPortID); + + /** Register a handler which can provide ports with port_type == + * handler_name */ + static void registerHandler(const std::string &handler_name, + Handler *handler); + + void init(); +}; + + +#endif // __MEM_EXTERNAL_SLAVE__ |