isa_fake.hh revision 8229
1/* 2 * Copyright (c) 2004-2005 The Regents of The University of Michigan 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions are 7 * met: redistributions of source code must retain the above copyright 8 * notice, this list of conditions and the following disclaimer; 9 * redistributions in binary form must reproduce the above copyright 10 * notice, this list of conditions and the following disclaimer in the 11 * documentation and/or other materials provided with the distribution; 12 * neither the name of the copyright holders nor the names of its 13 * contributors may be used to endorse or promote products derived from 14 * this software without specific prior written permission. 15 * 16 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 17 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 18 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR 19 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT 20 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 21 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT 22 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 23 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 24 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 25 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 26 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 27 * 28 * Authors: Ali Saidi 29 */ 30 31/** @file 32 * Declaration of a fake device. 33 */ 34 35#ifndef __ISA_FAKE_HH__ 36#define __ISA_FAKE_HH__ 37 38#include <string> 39 40#include "base/range.hh" 41#include "dev/io_device.hh" 42// #include "dev/alpha/tsunami.hh" 43#include "mem/packet.hh" 44#include "params/IsaFake.hh" 45 46/** 47 * IsaFake is a device that returns, BadAddr, 1 or 0 on all reads and 48 * rites. It is meant to be placed at an address range 49 * so that an mcheck doesn't occur when an os probes a piece of hw 50 * that doesn't exist (e.g. UARTs1-3), or catch requests in the memory system 51 * that have no responders.. 52 */ 53class IsaFake : public BasicPioDevice 54{ 55 protected: 56 uint8_t retData8; 57 uint16_t retData16; 58 uint32_t retData32; 59 uint64_t retData64; 60 61 public: 62 typedef IsaFakeParams Params; 63 const Params * 64 params() const 65 { 66 return dynamic_cast<const Params *>(_params); 67 } 68 /** 69 * The constructor for Isa Fake just registers itself with the MMU. 70 * @param p params structure 71 */ 72 IsaFake(Params *p); 73 74 /** 75 * This read always returns -1. 76 * @param pkt The memory request. 77 * @param data Where to put the data. 78 */ 79 virtual Tick read(PacketPtr pkt); 80 81 /** 82 * All writes are simply ignored. 83 * @param pkt The memory request. 84 * @param data the data to not write. 85 */ 86 virtual Tick write(PacketPtr pkt); 87}; 88 89#endif // __ISA_FAKE_HH__ 90