request.hh revision 2989 
1/*
2 * Copyright (c) 2002-2005 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: Ron Dreslinski
29 *          Steve Reinhardt
30 *          Ali Saidi
31 */
32
33/**
34 * @file
35 * Declaration of a request, the overall memory request consisting of
36 the parts of the request that are persistent throughout the transaction.
37 */
38
39#ifndef __MEM_REQUEST_HH__
40#define __MEM_REQUEST_HH__
41
42#include "sim/host.hh"
43#include "sim/root.hh"
44
45#include <cassert>
46
47class Request;
48
49typedef Request* RequestPtr;
50
51
52/** The request is a Load locked/store conditional. */
53const unsigned LOCKED		= 0x001;
54/** The virtual address is also the physical address. */
55const unsigned PHYSICAL		= 0x002;
56/** The request is an ALPHA VPTE pal access (hw_ld). */
57const unsigned VPTE		= 0x004;
58/** Use the alternate mode bits in ALPHA. */
59const unsigned ALTMODE		= 0x008;
60/** The request is to an uncacheable address. */
61const unsigned UNCACHEABLE	= 0x010;
62/** The request should not cause a page fault. */
63const unsigned NO_FAULT         = 0x020;
64/** The request should be prefetched into the exclusive state. */
65const unsigned PF_EXCLUSIVE	= 0x100;
66/** The request should be marked as LRU. */
67const unsigned EVICT_NEXT	= 0x200;
68/** The request should ignore unaligned access faults */
69const unsigned NO_ALIGN_FAULT   = 0x400;
70/** The request was an instruction read. */
71const unsigned INST_READ        = 0x800;
72
73class Request
74{
75  private:
76    /**
77     * The physical address of the request. Valid only if validPaddr
78     * is set. */
79    Addr paddr;
80
81    /**
82     * The size of the request. This field must be set when vaddr or
83     * paddr is written via setVirt() or setPhys(), so it is always
84     * valid as long as one of the address fields is valid.  */
85    int size;
86
87    /** Flag structure for the request. */
88    uint32_t flags;
89
90    /**
91     * The time this request was started. Used to calculate
92     * latencies. This field is set to curTick any time paddr or vaddr
93     * is written.  */
94    Tick time;
95
96    /** The address space ID. */
97    int asid;
98    /** The virtual address of the request. */
99    Addr vaddr;
100
101    /** The return value of store conditional. */
102    uint64_t scResult;
103
104    /** The cpu number (for statistics, typically). */
105    int cpuNum;
106    /** The requesting thread id (for statistics, typically). */
107    int  threadNum;
108
109    /** program counter of initiating access; for tracing/debugging */
110    Addr pc;
111
112    /** Whether or not paddr is valid (has been written yet). */
113    bool validPaddr;
114    /** Whether or not the asid & vaddr are valid. */
115    bool validAsidVaddr;
116    /** Whether or not the sc result is valid. */
117    bool validScResult;
118    /** Whether or not the cpu number & thread ID are valid. */
119    bool validCpuAndThreadNums;
120    /** Whether or not the pc is valid. */
121    bool validPC;
122
123  public:
124    /** Minimal constructor.  No fields are initialized. */
125    Request()
126        : validPaddr(false), validAsidVaddr(false),
127          validScResult(false), validCpuAndThreadNums(false), validPC(false)
128    {}
129
130    /**
131     * Constructor for physical (e.g. device) requests.  Initializes
132     * just physical address, size, flags, and timestamp (to curTick).
133     * These fields are adequate to perform a request.  */
134    Request(Addr _paddr, int _size, int _flags)
135        : validCpuAndThreadNums(false)
136    { setPhys(_paddr, _size, _flags); }
137
138    Request(int _asid, Addr _vaddr, int _size, int _flags, Addr _pc,
139            int _cpuNum, int _threadNum)
140    {
141        setThreadContext(_cpuNum, _threadNum);
142        setVirt(_asid, _vaddr, _size, _flags, _pc);
143    }
144
145    /**
146     * Set up CPU and thread numbers. */
147    void setThreadContext(int _cpuNum, int _threadNum)
148    {
149        cpuNum = _cpuNum;
150        threadNum = _threadNum;
151        validCpuAndThreadNums = true;
152    }
153
154    /**
155     * Set up a physical (e.g. device) request in a previously
156     * allocated Request object. */
157    void setPhys(Addr _paddr, int _size, int _flags)
158    {
159        paddr = _paddr;
160        size = _size;
161        flags = _flags;
162        time = curTick;
163        validPaddr = true;
164        validAsidVaddr = false;
165        validPC = false;
166        validScResult = false;
167    }
168
169    /**
170     * Set up a virtual (e.g., CPU) request in a previously
171     * allocated Request object. */
172    void setVirt(int _asid, Addr _vaddr, int _size, int _flags, Addr _pc)
173    {
174        asid = _asid;
175        vaddr = _vaddr;
176        size = _size;
177        flags = _flags;
178        pc = _pc;
179        time = curTick;
180        validPaddr = false;
181        validAsidVaddr = true;
182        validPC = true;
183        validScResult = false;
184    }
185
186    /** Set just the physical address.  This should only be used to
187     * record the result of a translation, and thus the vaddr must be
188     * valid before this method is called.  Otherwise, use setPhys()
189     * to guarantee that the size and flags are also set.
190     */
191    void setPaddr(Addr _paddr)
192    {
193        assert(validAsidVaddr);
194        paddr = _paddr;
195        validPaddr = true;
196    }
197
198    /** Accessor for paddr. */
199    Addr getPaddr() { assert(validPaddr); return paddr; }
200
201    /** Accessor for size. */
202    int getSize() { assert(validPaddr || validAsidVaddr); return size; }
203    /** Accessor for time. */
204    Tick getTime() { assert(validPaddr || validAsidVaddr); return time; }
205
206    /** Accessor for flags. */
207    uint32_t getFlags() { assert(validPaddr || validAsidVaddr); return flags; }
208    /** Accessor for paddr. */
209    void setFlags(uint32_t _flags)
210    { assert(validPaddr || validAsidVaddr); flags = _flags; }
211
212    /** Accessor function for vaddr.*/
213    Addr getVaddr() { assert(validAsidVaddr); return vaddr; }
214
215    /** Accessor function for asid.*/
216    int getAsid() { assert(validAsidVaddr); return asid; }
217
218    /** Accessor function to check if sc result is valid. */
219    bool scResultValid() { return validScResult; }
220    /** Accessor function for store conditional return value.*/
221    uint64_t getScResult() { assert(validScResult); return scResult; }
222    /** Accessor function for store conditional return value.*/
223    void setScResult(uint64_t _scResult)
224    { scResult = _scResult; validScResult = true; }
225
226    /** Accessor function for cpu number.*/
227    int getCpuNum() { assert(validCpuAndThreadNums); return cpuNum; }
228    /** Accessor function for thread number.*/
229    int getThreadNum()  { assert(validCpuAndThreadNums); return threadNum; }
230
231    /** Accessor function for pc.*/
232    Addr getPC() { assert(validPC); return pc; }
233
234    /** Accessor Function to Check Cacheability. */
235    bool isUncacheable() { return getFlags() & UNCACHEABLE; }
236
237    bool isInstRead() { return getFlags() & INST_READ; }
238
239    friend class Packet;
240};
241
242#endif // __MEM_REQUEST_HH__
243