request.hh revision 6104:ca0915f8d86d 
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 <cassert>
43
44#include "base/fast_alloc.hh"
45#include "base/flags.hh"
46#include "base/misc.hh"
47#include "sim/host.hh"
48#include "sim/core.hh"
49
50class Request;
51
52typedef Request* RequestPtr;
53
54class Request : public FastAlloc
55{
56  public:
57    typedef uint32_t FlagsType;
58    typedef ::Flags<FlagsType> Flags;
59
60    /** ASI information for this request if it exists. */
61    static const FlagsType ASI_BITS                    = 0x000000FF;
62    /** The request is a Load locked/store conditional. */
63    static const FlagsType LLSC                        = 0x00000100;
64    /** The virtual address is also the physical address. */
65    static const FlagsType PHYSICAL                    = 0x00000200;
66    /** The request is an ALPHA VPTE pal access (hw_ld). */
67    static const FlagsType VPTE                        = 0x00000400;
68    /** Use the alternate mode bits in ALPHA. */
69    static const FlagsType ALTMODE                     = 0x00000800;
70    /** The request is to an uncacheable address. */
71    static const FlagsType UNCACHEABLE                 = 0x00001000;
72    /** The request should not cause a page fault. */
73    static const FlagsType NO_FAULT                    = 0x00002000;
74    /** The request should not cause a memory access. */
75    static const FlagsType NO_ACCESS                   = 0x00004000;
76    /** This request will lock or unlock the accessed memory. When used with
77     * a load, the access locks the particular chunk of memory. When used
78     * with a store, it unlocks. The rule is that locked accesses have to be
79     * made up of a locked load, some operation on the data, and then a locked
80     * store.
81     */
82    static const FlagsType LOCKED                      = 0x00008000;
83    /** The request should be prefetched into the exclusive state. */
84    static const FlagsType PF_EXCLUSIVE                = 0x00010000;
85    /** The request should be marked as LRU. */
86    static const FlagsType EVICT_NEXT                  = 0x00020000;
87    /** The request should ignore unaligned access faults */
88    static const FlagsType NO_ALIGN_FAULT              = 0x00040000;
89    /** The request was an instruction read. */
90    static const FlagsType INST_READ                   = 0x00080000;
91    /** This request is for a memory swap. */
92    static const FlagsType MEM_SWAP                    = 0x00100000;
93    static const FlagsType MEM_SWAP_COND               = 0x00200000;
94    /** The request should ignore unaligned access faults */
95    static const FlagsType NO_HALF_WORD_ALIGN_FAULT    = 0x00400000;
96    /** This request is to a memory mapped register. */
97    static const FlagsType MMAPED_IPR                  = 0x00800000;
98
99    /** These flags are *not* cleared when a Request object is reused
100       (assigned a new address). */
101    static const FlagsType STICKY_FLAGS = INST_READ;
102
103  private:
104    typedef uint8_t PrivateFlagsType;
105    typedef ::Flags<PrivateFlagsType> PrivateFlags;
106
107    /** Whether or not the size is valid. */
108    static const PrivateFlagsType VALID_SIZE           = 0x00000001;
109    /** Whether or not paddr is valid (has been written yet). */
110    static const PrivateFlagsType VALID_PADDR          = 0x00000002;
111    /** Whether or not the vaddr & asid are valid. */
112    static const PrivateFlagsType VALID_VADDR          = 0x00000004;
113    /** Whether or not the pc is valid. */
114    static const PrivateFlagsType VALID_PC             = 0x00000010;
115    /** Whether or not the context ID is valid. */
116    static const PrivateFlagsType VALID_CONTEXT_ID     = 0x00000020;
117    static const PrivateFlagsType VALID_THREAD_ID      = 0x00000040;
118    /** Whether or not the sc result is valid. */
119    static const PrivateFlagsType VALID_EXTRA_DATA     = 0x00000080;
120
121    /** These flags are *not* cleared when a Request object is reused
122       (assigned a new address). */
123    static const PrivateFlagsType STICKY_PRIVATE_FLAGS =
124        VALID_CONTEXT_ID | VALID_THREAD_ID;
125
126  private:
127    /**
128     * The physical address of the request. Valid only if validPaddr
129     * is set.
130     */
131    Addr paddr;
132
133    /**
134     * The size of the request. This field must be set when vaddr or
135     * paddr is written via setVirt() or setPhys(), so it is always
136     * valid as long as one of the address fields is valid.
137     */
138    int size;
139
140    /** Flag structure for the request. */
141    Flags flags;
142
143    /** Private flags for field validity checking. */
144    PrivateFlags privateFlags;
145
146    /**
147     * The time this request was started. Used to calculate
148     * latencies. This field is set to curTick any time paddr or vaddr
149     * is written.
150     */
151    Tick time;
152
153    /** The address space ID. */
154    int asid;
155
156    /** The virtual address of the request. */
157    Addr vaddr;
158
159    /**
160     * Extra data for the request, such as the return value of
161     * store conditional or the compare value for a CAS. */
162    uint64_t extraData;
163
164    /** The context ID (for statistics, typically). */
165    int _contextId;
166    /** The thread ID (id within this CPU) */
167    int _threadId;
168
169    /** program counter of initiating access; for tracing/debugging */
170    Addr pc;
171
172  public:
173    /** Minimal constructor.  No fields are initialized. */
174    Request()
175    {}
176
177    /**
178     * Constructor for physical (e.g. device) requests.  Initializes
179     * just physical address, size, flags, and timestamp (to curTick).
180     * These fields are adequate to perform a request.
181     */
182    Request(Addr paddr, int size, Flags flags)
183    {
184        setPhys(paddr, size, flags);
185    }
186
187    Request(int asid, Addr vaddr, int size, Flags flags, Addr pc,
188            int cid, int tid)
189    {
190        setVirt(asid, vaddr, size, flags, pc);
191        setThreadContext(cid, tid);
192    }
193
194    ~Request() {}  // for FastAlloc
195
196    /**
197     * Set up CPU and thread numbers.
198     */
199    void
200    setThreadContext(int context_id, int thread_id)
201    {
202        _contextId = context_id;
203        _threadId = thread_id;
204        privateFlags.set(VALID_CONTEXT_ID|VALID_THREAD_ID);
205    }
206
207    /**
208     * Set up a physical (e.g. device) request in a previously
209     * allocated Request object.
210     */
211    void
212    setPhys(Addr _paddr, int _size, Flags _flags)
213    {
214        assert(_size >= 0);
215        paddr = _paddr;
216        size = _size;
217        time = curTick;
218
219        flags.clear(~STICKY_FLAGS);
220        flags.set(_flags);
221        privateFlags.clear(~STICKY_PRIVATE_FLAGS);
222        privateFlags.set(VALID_PADDR|VALID_SIZE);
223    }
224
225    /**
226     * Set up a virtual (e.g., CPU) request in a previously
227     * allocated Request object.
228     */
229    void
230    setVirt(int _asid, Addr _vaddr, int _size, Flags _flags, Addr _pc)
231    {
232        assert(_size >= 0);
233        asid = _asid;
234        vaddr = _vaddr;
235        size = _size;
236        flags = _flags;
237        pc = _pc;
238        time = curTick;
239
240        flags.clear(~STICKY_FLAGS);
241        flags.set(_flags);
242        privateFlags.clear(~STICKY_PRIVATE_FLAGS);
243        privateFlags.set(VALID_VADDR|VALID_SIZE|VALID_PC);
244    }
245
246    /**
247     * Set just the physical address.  This should only be used to
248     * record the result of a translation, and thus the vaddr must be
249     * valid before this method is called.  Otherwise, use setPhys()
250     * to guarantee that the size and flags are also set.
251     */
252    void
253    setPaddr(Addr _paddr)
254    {
255        assert(privateFlags.isSet(VALID_VADDR));
256        paddr = _paddr;
257        privateFlags.set(VALID_PADDR);
258    }
259
260    /**
261     * Generate two requests as if this request had been split into two
262     * pieces. The original request can't have been translated already.
263     */
264    void splitOnVaddr(Addr split_addr, RequestPtr &req1, RequestPtr &req2)
265    {
266        assert(privateFlags.isSet(VALID_VADDR));
267        assert(privateFlags.noneSet(VALID_PADDR));
268        assert(split_addr > vaddr && split_addr < vaddr + size);
269        req1 = new Request;
270        *req1 = *this;
271        req2 = new Request;
272        *req2 = *this;
273        req1->size = split_addr - vaddr;
274        req2->vaddr = split_addr;
275        req2->size = size - req1->size;
276    }
277
278    /**
279     * Accessor for paddr.
280     */
281    bool
282    hasPaddr()
283    {
284        return privateFlags.isSet(VALID_PADDR);
285    }
286
287    Addr
288    getPaddr()
289    {
290        assert(privateFlags.isSet(VALID_PADDR));
291        return paddr;
292    }
293
294    /**
295     *  Accessor for size.
296     */
297    bool
298    hasSize()
299    {
300        return privateFlags.isSet(VALID_SIZE);
301    }
302
303    int
304    getSize()
305    {
306        assert(privateFlags.isSet(VALID_SIZE));
307        return size;
308    }
309
310    /** Accessor for time. */
311    Tick
312    getTime()
313    {
314        assert(privateFlags.isSet(VALID_PADDR|VALID_VADDR));
315        return time;
316    }
317
318    /** Accessor for flags. */
319    Flags
320    getFlags()
321    {
322        assert(privateFlags.isSet(VALID_PADDR|VALID_VADDR));
323        return flags;
324    }
325
326    void
327    setFlags(Flags _flags)
328    {
329        assert(privateFlags.isSet(VALID_PADDR|VALID_VADDR));
330        flags.set(_flags);
331    }
332
333    /** Accessor function for vaddr.*/
334    Addr
335    getVaddr()
336    {
337        assert(privateFlags.isSet(VALID_VADDR));
338        return vaddr;
339    }
340
341    /** Accessor function for asid.*/
342    int
343    getAsid()
344    {
345        assert(privateFlags.isSet(VALID_VADDR));
346        return asid;
347    }
348
349    /** Accessor function for asi.*/
350    uint8_t
351    getAsi()
352    {
353        assert(privateFlags.isSet(VALID_VADDR));
354        return flags & ASI_BITS;
355    }
356
357    /** Accessor function for MMAPED_IPR flag. */
358    bool
359    isMmapedIpr()
360    {
361        assert(privateFlags.isSet(VALID_PADDR));
362        return flags.isSet(MMAPED_IPR);
363    }
364
365    void
366    setMmapedIpr(bool r)
367    {
368        assert(VALID_VADDR);
369        flags.set(MMAPED_IPR);
370    }
371
372    /** Accessor function to check if sc result is valid. */
373    bool
374    extraDataValid()
375    {
376        return privateFlags.isSet(VALID_EXTRA_DATA);
377    }
378
379    /** Accessor function for store conditional return value.*/
380    uint64_t
381    getExtraData() const
382    {
383        assert(privateFlags.isSet(VALID_EXTRA_DATA));
384        return extraData;
385    }
386
387    /** Accessor function for store conditional return value.*/
388    void
389    setExtraData(uint64_t _extraData)
390    {
391        extraData = _extraData;
392        privateFlags.set(VALID_EXTRA_DATA);
393    }
394
395    bool
396    hasContextId() const
397    {
398        return privateFlags.isSet(VALID_CONTEXT_ID);
399    }
400
401    /** Accessor function for context ID.*/
402    int
403    contextId() const
404    {
405        assert(privateFlags.isSet(VALID_CONTEXT_ID));
406        return _contextId;
407    }
408
409    /** Accessor function for thread ID. */
410    int
411    threadId() const
412    {
413        assert(privateFlags.isSet(VALID_THREAD_ID));
414        return _threadId;
415    }
416
417    bool
418    hasPC() const
419    {
420        return privateFlags.isSet(VALID_PC);
421    }
422
423    /** Accessor function for pc.*/
424    Addr
425    getPC() const
426    {
427        assert(privateFlags.isSet(VALID_PC));
428        return pc;
429    }
430
431    /** Accessor Function to Check Cacheability. */
432    bool isUncacheable() const { return flags.isSet(UNCACHEABLE); }
433    bool isInstRead() const { return flags.isSet(INST_READ); }
434    bool isLLSC() const { return flags.isSet(LLSC); }
435    bool isLocked() const { return flags.isSet(LOCKED); }
436    bool isSwap() const { return flags.isSet(MEM_SWAP|MEM_SWAP_COND); }
437    bool isCondSwap() const { return flags.isSet(MEM_SWAP_COND); }
438
439    bool
440    isMisaligned() const
441    {
442        if (flags.isSet(NO_ALIGN_FAULT))
443            return false;
444
445        if ((vaddr & 0x1))
446            return true;
447
448        if (flags.isSet(NO_HALF_WORD_ALIGN_FAULT))
449            return false;
450
451        if ((vaddr & 0x2))
452            return true;
453
454        return false;
455    }
456};
457
458#endif // __MEM_REQUEST_HH__
459