request.hh revision 2982 
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 "arch/isa_traits.hh"
43#include "sim/root.hh"
44
45class Request;
46
47typedef Request* RequestPtr;
48
49
50/** The request is a Load locked/store conditional. */
51const unsigned LOCKED		= 0x001;
52/** The virtual address is also the physical address. */
53const unsigned PHYSICAL		= 0x002;
54/** The request is an ALPHA VPTE pal access (hw_ld). */
55const unsigned VPTE		= 0x004;
56/** Use the alternate mode bits in ALPHA. */
57const unsigned ALTMODE		= 0x008;
58/** The request is to an uncacheable address. */
59const unsigned UNCACHEABLE	= 0x010;
60/** The request should not cause a page fault. */
61const unsigned NO_FAULT         = 0x020;
62/** The request should be prefetched into the exclusive state. */
63const unsigned PF_EXCLUSIVE	= 0x100;
64/** The request should be marked as LRU. */
65const unsigned EVICT_NEXT	= 0x200;
66/** The request should ignore unaligned access faults */
67const unsigned NO_ALIGN_FAULT   = 0x400;
68/** The request was an instruction read. */
69const unsigned INST_READ        = 0x800;
70
71class Request
72{
73  private:
74    /**
75     * The physical address of the request. Valid only if validPaddr
76     * is set. */
77    Addr paddr;
78
79    /**
80     * The size of the request. This field must be set when vaddr or
81     * paddr is written via setVirt() or setPhys(), so it is always
82     * valid as long as one of the address fields is valid.  */
83    int size;
84
85    /** Flag structure for the request. */
86    uint32_t flags;
87
88    /**
89     * The time this request was started. Used to calculate
90     * latencies. This field is set to curTick any time paddr or vaddr
91     * is written.  */
92    Tick time;
93
94    /** The address space ID. */
95    int asid;
96    /** The virtual address of the request. */
97    Addr vaddr;
98
99    /** The return value of store conditional. */
100    uint64_t scResult;
101
102    /** The cpu number (for statistics, typically). */
103    int cpuNum;
104    /** The requesting thread id (for statistics, typically). */
105    int  threadNum;
106
107    /** program counter of initiating access; for tracing/debugging */
108    Addr pc;
109
110    /** Whether or not paddr is valid (has been written yet). */
111    bool validPaddr;
112    /** Whether or not the asid & vaddr are valid. */
113    bool validAsidVaddr;
114    /** Whether or not the sc result is valid. */
115    bool validScResult;
116    /** Whether or not the cpu number & thread ID are valid. */
117    bool validCpuAndThreadNums;
118    /** Whether or not the pc is valid. */
119    bool validPC;
120
121  public:
122    /** Minimal constructor.  No fields are initialized. */
123    Request()
124        : validPaddr(false), validAsidVaddr(false),
125          validScResult(false), validCpuAndThreadNums(false), validPC(false)
126    {}
127
128    /**
129     * Constructor for physical (e.g. device) requests.  Initializes
130     * just physical address, size, flags, and timestamp (to curTick).
131     * These fields are adequate to perform a request.  */
132    Request(Addr _paddr, int _size, int _flags)
133        : validCpuAndThreadNums(false)
134    { setPhys(_paddr, _size, _flags); }
135
136    Request(int _asid, Addr _vaddr, int _size, int _flags, Addr _pc,
137            int _cpuNum, int _threadNum)
138    {
139        setThreadContext(_cpuNum, _threadNum);
140        setVirt(_asid, _vaddr, _size, _flags, _pc);
141    }
142
143    /**
144     * Set up CPU and thread numbers. */
145    void setThreadContext(int _cpuNum, int _threadNum)
146    {
147        cpuNum = _cpuNum;
148        threadNum = _threadNum;
149        validCpuAndThreadNums = true;
150    }
151
152    /**
153     * Set up a physical (e.g. device) request in a previously
154     * allocated Request object. */
155    void setPhys(Addr _paddr, int _size, int _flags)
156    {
157        paddr = _paddr;
158        size = _size;
159        flags = _flags;
160        time = curTick;
161        validPaddr = true;
162        validAsidVaddr = false;
163        validPC = false;
164        validScResult = false;
165    }
166
167    /**
168     * Set up a virtual (e.g., CPU) request in a previously
169     * allocated Request object. */
170    void setVirt(int _asid, Addr _vaddr, int _size, int _flags, Addr _pc)
171    {
172        asid = _asid;
173        vaddr = _vaddr;
174        size = _size;
175        flags = _flags;
176        pc = _pc;
177        time = curTick;
178        validPaddr = false;
179        validAsidVaddr = true;
180        validPC = true;
181        validScResult = false;
182    }
183
184    /** Set just the physical address.  This should only be used to
185     * record the result of a translation, and thus the vaddr must be
186     * valid before this method is called.  Otherwise, use setPhys()
187     * to guarantee that the size and flags are also set.
188     */
189    void setPaddr(Addr _paddr)
190    {
191        assert(validAsidVaddr);
192        paddr = _paddr;
193        validPaddr = true;
194    }
195
196    /** Accessor for paddr. */
197    Addr getPaddr() { assert(validPaddr); return paddr; }
198
199    /** Accessor for size. */
200    int getSize() { assert(validPaddr || validAsidVaddr); return size; }
201    /** Accessor for time. */
202    Tick getTime() { assert(validPaddr || validAsidVaddr); return time; }
203
204    /** Accessor for flags. */
205    uint32_t getFlags() { assert(validPaddr || validAsidVaddr); return flags; }
206    /** Accessor for paddr. */
207    void setFlags(uint32_t _flags)
208    { assert(validPaddr || validAsidVaddr); flags = _flags; }
209
210    /** Accessor function for vaddr.*/
211    Addr getVaddr() { assert(validAsidVaddr); return vaddr; }
212
213    /** Accessor function for asid.*/
214    int getAsid() { assert(validAsidVaddr); return asid; }
215
216    /** Accessor function to check if sc result is valid. */
217    bool scResultValid() { return validScResult; }
218    /** Accessor function for store conditional return value.*/
219    uint64_t getScResult() { assert(validScResult); return scResult; }
220    /** Accessor function for store conditional return value.*/
221    void setScResult(uint64_t _scResult)
222    { scResult = _scResult; validScResult = true; }
223
224    /** Accessor function for cpu number.*/
225    int getCpuNum() { assert(validCpuAndThreadNums); return cpuNum; }
226    /** Accessor function for thread number.*/
227    int getThreadNum()  { assert(validCpuAndThreadNums); return threadNum; }
228
229    /** Accessor function for pc.*/
230    Addr getPC() { assert(validPC); return pc; }
231
232    /** Accessor Function to Check Cacheability. */
233    bool isUncacheable() { return getFlags() & UNCACHEABLE; }
234
235    bool isInstRead() { return getFlags() & INST_READ; }
236
237    friend class Packet;
238};
239
240#endif // __MEM_REQUEST_HH__
241