request.hh revision 2812:8e5feae75615 
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 Decleration of a request, the overall memory request consisting of
35 the parts of the request that are persistent throughout the transaction.
36 */
37
38#ifndef __MEM_REQUEST_HH__
39#define __MEM_REQUEST_HH__
40
41#include "arch/isa_traits.hh"
42
43class Request;
44
45typedef Request* RequestPtr;
46
47
48/** The request is a Load locked/store conditional. */
49const unsigned LOCKED		= 0x001;
50/** The virtual address is also the physical address. */
51const unsigned PHYSICAL		= 0x002;
52/** The request is an ALPHA VPTE pal access (hw_ld). */
53const unsigned VPTE		= 0x004;
54/** Use the alternate mode bits in ALPHA. */
55const unsigned ALTMODE		= 0x008;
56/** The request is to an uncacheable address. */
57const unsigned UNCACHEABLE	= 0x010;
58/** The request should not cause a page fault. */
59const unsigned NO_FAULT         = 0x020;
60/** The request should be prefetched into the exclusive state. */
61const unsigned PF_EXCLUSIVE	= 0x100;
62/** The request should be marked as LRU. */
63const unsigned EVICT_NEXT	= 0x200;
64/** The request should ignore unaligned access faults */
65const unsigned NO_ALIGN_FAULT   = 0x400;
66
67class Request
68{
69  private:
70    /**
71     * The physical address of the request. Valid only if validPaddr
72     * is set. */
73    Addr paddr;
74
75    /**
76     * The size of the request. This field must be set when vaddr or
77     * paddr is written via setVirt() or setPhys(), so it is always
78     * valid as long as one of the address fields is valid.  */
79    int size;
80
81    /** Flag structure for the request. */
82    uint32_t flags;
83
84    /**
85     * The time this request was started. Used to calculate
86     * latencies. This field is set to curTick any time paddr or vaddr
87     * is written.  */
88    Tick time;
89
90    /** The address space ID. */
91    int asid;
92    /** The virtual address of the request. */
93    Addr vaddr;
94
95    /** The return value of store conditional. */
96    uint64_t scResult;
97
98    /** The cpu number (for statistics, typically). */
99    int cpuNum;
100    /** The requesting thread id (for statistics, typically). */
101    int  threadNum;
102
103    /** program counter of initiating access; for tracing/debugging */
104    Addr pc;
105
106    /** Whether or not paddr is valid (has been written yet). */
107    bool validPaddr;
108    /** Whether or not the asid & vaddr are valid. */
109    bool validAsidVaddr;
110    /** Whether or not the sc result is valid. */
111    bool validScResult;
112    /** Whether or not the cpu number & thread ID are valid. */
113    bool validCpuAndThreadNums;
114    /** Whether or not the pc is valid. */
115    bool validPC;
116
117  public:
118    /** Minimal constructor.  No fields are initialized. */
119    Request()
120        : validPaddr(false), validAsidVaddr(false),
121          validScResult(false), validCpuAndThreadNums(false), validPC(false)
122    {}
123
124    /**
125     * Constructor for physical (e.g. device) requests.  Initializes
126     * just physical address, size, flags, and timestamp (to curTick).
127     * These fields are adequate to perform a request.  */
128    Request(Addr _paddr, int _size, int _flags)
129        : validCpuAndThreadNums(false)
130    { setPhys(_paddr, _size, _flags); }
131
132    Request(int _asid, Addr _vaddr, int _size, int _flags, Addr _pc,
133            int _cpuNum, int _threadNum)
134    {
135        setThreadContext(_cpuNum, _threadNum);
136        setVirt(_asid, _vaddr, _size, _flags, _pc);
137    }
138
139    /**
140     * Set up CPU and thread numbers. */
141    void setThreadContext(int _cpuNum, int _threadNum)
142    {
143        cpuNum = _cpuNum;
144        threadNum = _threadNum;
145        validCpuAndThreadNums = true;
146    }
147
148    /**
149     * Set up a physical (e.g. device) request in a previously
150     * allocated Request object. */
151    void setPhys(Addr _paddr, int _size, int _flags)
152    {
153        paddr = _paddr;
154        size = _size;
155        flags = _flags;
156        time = curTick;
157        validPaddr = true;
158        validAsidVaddr = false;
159        validPC = false;
160        validScResult = false;
161    }
162
163    /**
164     * Set up a virtual (e.g., CPU) request in a previously
165     * allocated Request object. */
166    void setVirt(int _asid, Addr _vaddr, int _size, int _flags, Addr _pc)
167    {
168        asid = _asid;
169        vaddr = _vaddr;
170        size = _size;
171        flags = _flags;
172        pc = _pc;
173        time = curTick;
174        validPaddr = false;
175        validAsidVaddr = true;
176        validPC = true;
177        validScResult = false;
178    }
179
180    /** Set just the physical address.  This should only be used to
181     * record the result of a translation, and thus the vaddr must be
182     * valid before this method is called.  Otherwise, use setPhys()
183     * to guarantee that the size and flags are also set.
184     */
185    void setPaddr(Addr _paddr)
186    {
187        assert(validAsidVaddr);
188        paddr = _paddr;
189        validPaddr = true;
190    }
191
192    /** Accessor for paddr. */
193    Addr getPaddr() { assert(validPaddr); return paddr; }
194
195    /** Accessor for size. */
196    int getSize() { assert(validPaddr || validAsidVaddr); return size; }
197    /** Accessor for time. */
198    Tick getTime() { assert(validPaddr || validAsidVaddr); return time; }
199
200    /** Accessor for flags. */
201    uint32_t getFlags() { assert(validPaddr || validAsidVaddr); return flags; }
202    /** Accessor for paddr. */
203    void setFlags(uint32_t _flags)
204    { assert(validPaddr || validAsidVaddr); flags = _flags; }
205
206    /** Accessor function for vaddr.*/
207    Addr getVaddr() { assert(validAsidVaddr); return vaddr; }
208
209    /** Accessor function for asid.*/
210    int getAsid() { assert(validAsidVaddr); return asid; }
211
212    /** Accessor function to check if sc result is valid. */
213    bool scResultValid() { return validScResult; }
214    /** Accessor function for store conditional return value.*/
215    uint64_t getScResult() { assert(validScResult); return scResult; }
216    /** Accessor function for store conditional return value.*/
217    void setScResult(uint64_t _scResult)
218    { scResult = _scResult; validScResult = true; }
219
220    /** Accessor function for cpu number.*/
221    int getCpuNum() { assert(validCpuAndThreadNums); return cpuNum; }
222    /** Accessor function for thread number.*/
223    int getThreadNum()  { assert(validCpuAndThreadNums); return threadNum; }
224
225    /** Accessor function for pc.*/
226    Addr getPC() { assert(validPC); return pc; }
227
228    /** Accessor Function to Check Cacheability. */
229    bool isUncacheable() { return getFlags() & UNCACHEABLE; }
230
231    friend class Packet;
232};
233
234#endif // __MEM_REQUEST_HH__
235