src/mem/port_proxy.hh

   1 /*
   2  * Copyright (c) 2011-2013 ARM Limited
   3  * All rights reserved
   4  *
   5  * The license below extends only to copyright in the software and shall
   6  * not be construed as granting a license to any other intellectual
   7  * property including but not limited to intellectual property relating
   8  * to a hardware implementation of the functionality of the software
   9  * licensed hereunder.  You may use the software subject to the license
  10  * terms below provided that you ensure that this notice is replicated
  11  * unmodified and in its entirety in all distributions of the software,
  12  * modified or unmodified, in source code or in binary form.
  13  *
  14  * Redistribution and use in source and binary forms, with or without
  15  * modification, are permitted provided that the following conditions are
  16  * met: redistributions of source code must retain the above copyright
  17  * notice, this list of conditions and the following disclaimer;
  18  * redistributions in binary form must reproduce the above copyright
  19  * notice, this list of conditions and the following disclaimer in the
  20  * documentation and/or other materials provided with the distribution;
  21  * neither the name of the copyright holders nor the names of its
  22  * contributors may be used to endorse or promote products derived from
  23  * this software without specific prior written permission.
  24  *
  25  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  26  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  27  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
  28  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  29  * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  30  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
  31  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  32  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  33  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  34  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  35  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  36  *
  37  * Authors: Andreas Hansson
  38  */
  39
  40 /**
  41  * @file
  42  * PortProxy Object Declaration.
  43  *
  44  * Port proxies are used when non-structural entities need access to
  45  * the memory system (or structural entities that want to peak into
  46  * the memory system without making a real memory access).
  47  *
  48  * Proxy objects replace the previous FunctionalPort, TranslatingPort
  49  * and VirtualPort objects, which provided the same functionality as
  50  * the proxies, but were instances of ports not corresponding to real
  51  * structural ports of the simulated system. Via the port proxies all
  52  * the accesses go through an actual port (either the system port,
  53  * e.g. for processes or initialisation, or a the data port of the
  54  * CPU, e.g. for threads) and thus are transparent to a potentially
  55  * distributed memory and automatically adhere to the memory map of
  56  * the system.
  57  */
  58
  59 #ifndef __MEM_PORT_PROXY_HH__
  60 #define __MEM_PORT_PROXY_HH__
  61
  62 #include "config/the_isa.hh"
  63 #if THE_ISA != NULL_ISA
  64     #include "arch/isa_traits.hh"
  65 #endif
  66
  67 #include "mem/port.hh"
  68 #include "sim/byteswap.hh"
  69
  70 /**
  71  * This object is a proxy for a structural port, to be used for debug
  72  * accesses.
  73  *
  74  * This proxy object is used when non structural entities
  75  * (e.g. thread contexts, object file loaders) need access to the
  76  * memory system. It calls the corresponding functions on the underlying
  77  * structural port, and provides templatized convenience access functions.
  78  *
  79  * The addresses are interpreted as physical addresses.
  80  *
  81  * @sa SETranslatingProxy
  82  * @sa FSTranslatingProxy
  83  */
  84 class PortProxy
  85 {
  86   private:
  87
  88     /** The actual physical port used by this proxy. */
  89     MasterPort &_port;
  90
  91     /** Granularity of any transactions issued through this proxy. */
  92     const unsigned int _cacheLineSize;
  93
  94     void blobHelper(Addr addr, uint8_t *p, int size, MemCmd cmd) const;
  95
  96   public:
  97     PortProxy(MasterPort &port, unsigned int cacheLineSize) :
  98         _port(port), _cacheLineSize(cacheLineSize) { }
  99     virtual ~PortProxy() { }
 100
 101     /**
 102      * Read size bytes memory at address and store in p.
 103      */
 104     virtual void readBlob(Addr addr, uint8_t* p, int size) const
 105     { blobHelper(addr, p, size, MemCmd::ReadReq); }
 106
 107     /**
 108      * Write size bytes from p to address.
 109      */
 110     virtual void writeBlob(Addr addr, uint8_t* p, int size) const
 111     { blobHelper(addr, p, size, MemCmd::WriteReq); }
 112
 113     /**
 114      * Fill size bytes starting at addr with byte value val.
 115      */
 116     virtual void memsetBlob(Addr addr, uint8_t v, int size) const;
 117
 118     /**
 119      * Read sizeof(T) bytes from address and return as object T.
 120      */
 121     template <typename T>
 122     T read(Addr address) const;
 123
 124     /**
 125      * Write object T to address. Writes sizeof(T) bytes.
 126      */
 127     template <typename T>
 128     void write(Addr address, T data) const;
 129
 130 #if THE_ISA != NULL_ISA
 131     /**
 132      * Read sizeof(T) bytes from address and return as object T.
 133      * Performs Guest to Host endianness transform.
 134      */
 135     template <typename T>
 136     T readGtoH(Addr address) const;
 137
 138     /**
 139      * Write object T to address. Writes sizeof(T) bytes.
 140      * Performs Host to Guest endianness transform.
 141      */
 142     template <typename T>
 143     void writeHtoG(Addr address, T data) const;
 144 #endif
 145 };
 146
 147
 148 template <typename T>
 149 T
 150 PortProxy::read(Addr address) const
 151 {
 152     T data;
 153     readBlob(address, (uint8_t*)&data, sizeof(T));
 154     return data;
 155 }
 156
 157 template <typename T>
 158 void
 159 PortProxy::write(Addr address, T data) const
 160 {
 161     writeBlob(address, (uint8_t*)&data, sizeof(T));
 162 }
 163
 164 #if THE_ISA != NULL_ISA
 165 template <typename T>
 166 T
 167 PortProxy::readGtoH(Addr address) const
 168 {
 169     T data;
 170     readBlob(address, (uint8_t*)&data, sizeof(T));
 171     return TheISA::gtoh(data);
 172 }
 173
 174 template <typename T>
 175 void
 176 PortProxy::writeHtoG(Addr address, T data) const
 177 {
 178     data = TheISA::htog(data);
 179     writeBlob(address, (uint8_t*)&data, sizeof(T));
 180 }
 181 #endif
 182
 183 #endif // __MEM_PORT_PROXY_HH__