request.hh revision 6103 
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    friend class Packet;
57
58  public:
59    typedef uint32_t FlagsType;
60    typedef ::Flags<FlagsType> Flags;
61
62    /** ASI information for this request if it exists. */
63    static const FlagsType ASI_BITS                    = 0x000000FF;
64    /** The request is a Load locked/store conditional. */
65    static const FlagsType LLSC                        = 0x00000100;
66    /** The virtual address is also the physical address. */
67    static const FlagsType PHYSICAL                    = 0x00000200;
68    /** The request is an ALPHA VPTE pal access (hw_ld). */
69    static const FlagsType VPTE                        = 0x00000400;
70    /** Use the alternate mode bits in ALPHA. */
71    static const FlagsType ALTMODE                     = 0x00000800;
72    /** The request is to an uncacheable address. */
73    static const FlagsType UNCACHEABLE                 = 0x00001000;
74    /** The request should not cause a page fault. */
75    static const FlagsType NO_FAULT                    = 0x00002000;
76    /** The request should not cause a memory access. */
77    static const FlagsType NO_ACCESS                   = 0x00004000;
78    /** This request will lock or unlock the accessed memory. When used with
79     * a load, the access locks the particular chunk of memory. When used
80     * with a store, it unlocks. The rule is that locked accesses have to be
81     * made up of a locked load, some operation on the data, and then a locked
82     * store.
83     */
84    static const FlagsType LOCKED                      = 0x00008000;
85    /** The request should be prefetched into the exclusive state. */
86    static const FlagsType PF_EXCLUSIVE                = 0x00010000;
87    /** The request should be marked as LRU. */
88    static const FlagsType EVICT_NEXT                  = 0x00020000;
89    /** The request should ignore unaligned access faults */
90    static const FlagsType NO_ALIGN_FAULT              = 0x00040000;
91    /** The request was an instruction read. */
92    static const FlagsType INST_READ                   = 0x00080000;
93    /** This request is for a memory swap. */
94    static const FlagsType MEM_SWAP                    = 0x00100000;
95    static const FlagsType MEM_SWAP_COND               = 0x00200000;
96    /** The request should ignore unaligned access faults */
97    static const FlagsType NO_HALF_WORD_ALIGN_FAULT    = 0x00400000;
98    /** This request is to a memory mapped register. */
99    static const FlagsType MMAPED_IPR                  = 0x00800000;
100
101  private:
102    static const FlagsType PUBLIC_FLAGS                = 0x00FFFFFF;
103    static const FlagsType PRIVATE_FLAGS               = 0xFF000000;
104
105    /** Whether or not the size is valid. */
106    static const FlagsType VALID_SIZE                  = 0x01000000;
107    /** Whether or not paddr is valid (has been written yet). */
108    static const FlagsType VALID_PADDR                 = 0x02000000;
109    /** Whether or not the vaddr & asid are valid. */
110    static const FlagsType VALID_VADDR                 = 0x04000000;
111    /** Whether or not the pc is valid. */
112    static const FlagsType VALID_PC                    = 0x10000000;
113    /** Whether or not the context ID is valid. */
114    static const FlagsType VALID_CONTEXT_ID            = 0x20000000;
115    static const FlagsType VALID_THREAD_ID             = 0x40000000;
116    /** Whether or not the sc result is valid. */
117    static const FlagsType VALID_EXTRA_DATA            = 0x80000000;
118
119  private:
120    /**
121     * The physical address of the request. Valid only if validPaddr
122     * is set.
123     */
124    Addr paddr;
125
126    /**
127     * The size of the request. This field must be set when vaddr or
128     * paddr is written via setVirt() or setPhys(), so it is always
129     * valid as long as one of the address fields is valid.
130     */
131    int size;
132
133    /** Flag structure for the request. */
134    Flags flags;
135
136    /**
137     * The time this request was started. Used to calculate
138     * latencies. This field is set to curTick any time paddr or vaddr
139     * is written.
140     */
141    Tick time;
142
143    /** The address space ID. */
144    int asid;
145
146    /** The virtual address of the request. */
147    Addr vaddr;
148
149    /**
150     * Extra data for the request, such as the return value of
151     * store conditional or the compare value for a CAS. */
152    uint64_t extraData;
153
154    /** The context ID (for statistics, typically). */
155    int _contextId;
156    /** The thread ID (id within this CPU) */
157    int _threadId;
158
159    /** program counter of initiating access; for tracing/debugging */
160    Addr pc;
161
162  public:
163    /** Minimal constructor.  No fields are initialized. */
164    Request()
165    {}
166
167    /**
168     * Constructor for physical (e.g. device) requests.  Initializes
169     * just physical address, size, flags, and timestamp (to curTick).
170     * These fields are adequate to perform a request.
171     */
172    Request(Addr paddr, int size, Flags flags)
173    {
174        setPhys(paddr, size, flags);
175    }
176
177    Request(int asid, Addr vaddr, int size, Flags flags, Addr pc,
178            int cid, int tid)
179    {
180        setThreadContext(cid, tid);
181        setVirt(asid, vaddr, size, flags, pc);
182    }
183
184    ~Request() {}  // for FastAlloc
185
186    /**
187     * Set up CPU and thread numbers.
188     */
189    void
190    setThreadContext(int context_id, int thread_id)
191    {
192        _contextId = context_id;
193        _threadId = thread_id;
194        flags.set(VALID_CONTEXT_ID|VALID_THREAD_ID);
195    }
196
197    /**
198     * Set up a physical (e.g. device) request in a previously
199     * allocated Request object.
200     */
201    void
202    setPhys(Addr _paddr, int _size, Flags _flags)
203    {
204        assert(_size >= 0);
205        paddr = _paddr;
206        size = _size;
207        time = curTick;
208
209        flags.set(VALID_PADDR|VALID_SIZE);
210        flags.clear(VALID_VADDR|VALID_PC|VALID_EXTRA_DATA|MMAPED_IPR);
211        flags.update(_flags, PUBLIC_FLAGS);
212    }
213
214    /**
215     * Set up a virtual (e.g., CPU) request in a previously
216     * allocated Request object.
217     */
218    void
219    setVirt(int _asid, Addr _vaddr, int _size, Flags _flags, Addr _pc)
220    {
221        assert(_size >= 0);
222        asid = _asid;
223        vaddr = _vaddr;
224        size = _size;
225        pc = _pc;
226        time = curTick;
227
228        flags.set(VALID_VADDR|VALID_SIZE|VALID_PC);
229        flags.clear(VALID_PADDR|VALID_EXTRA_DATA|MMAPED_IPR);
230        flags.update(_flags, PUBLIC_FLAGS);
231    }
232
233    /**
234     * Set just the physical address.  This should only be used to
235     * record the result of a translation, and thus the vaddr must be
236     * valid before this method is called.  Otherwise, use setPhys()
237     * to guarantee that the size and flags are also set.
238     */
239    void
240    setPaddr(Addr _paddr)
241    {
242        assert(flags.isSet(VALID_VADDR));
243        paddr = _paddr;
244        flags.set(VALID_PADDR);
245    }
246
247    /**
248     * Generate two requests as if this request had been split into two
249     * pieces. The original request can't have been translated already.
250     */
251    void splitOnVaddr(Addr split_addr, RequestPtr &req1, RequestPtr &req2)
252    {
253        assert(flags.isSet(VALID_VADDR));
254        assert(flags.noneSet(VALID_PADDR));
255        assert(split_addr > vaddr && split_addr < vaddr + size);
256        req1 = new Request;
257        *req1 = *this;
258        req2 = new Request;
259        *req2 = *this;
260        req1->size = split_addr - vaddr;
261        req2->vaddr = split_addr;
262        req2->size = size - req1->size;
263    }
264
265    /**
266     * Accessor for paddr.
267     */
268    Addr
269    getPaddr()
270    {
271        assert(flags.isSet(VALID_PADDR));
272        return paddr;
273    }
274
275    /**
276     *  Accessor for size.
277     */
278    int
279    getSize()
280    {
281        assert(flags.isSet(VALID_SIZE));
282        return size;
283    }
284
285    /** Accessor for time. */
286    Tick
287    getTime()
288    {
289        assert(flags.isSet(VALID_PADDR|VALID_VADDR));
290        return time;
291    }
292
293    void
294    setTime(Tick when)
295    {
296        assert(flags.isSet(VALID_PADDR|VALID_VADDR));
297        time = when;
298    }
299
300    /** Accessor for flags. */
301    Flags
302    getFlags()
303    {
304        assert(flags.isSet(VALID_PADDR|VALID_VADDR));
305        return flags & PUBLIC_FLAGS;
306    }
307
308    Flags
309    anyFlags(Flags _flags)
310    {
311        assert(flags.isSet(VALID_PADDR|VALID_VADDR));
312        assert(_flags.noneSet(~PUBLIC_FLAGS));
313        return flags.isSet(_flags);
314    }
315
316    Flags
317    allFlags(Flags _flags)
318    {
319        assert(flags.isSet(VALID_PADDR|VALID_VADDR));
320        assert(_flags.noneSet(~PUBLIC_FLAGS));
321        return flags.allSet(_flags);
322    }
323
324    /** Accessor for flags. */
325    void
326    setFlags(Flags _flags)
327    {
328        assert(flags.isSet(VALID_PADDR|VALID_VADDR));
329        assert(_flags.noneSet(~PUBLIC_FLAGS));
330        flags.set(_flags);
331    }
332
333    void
334    clearFlags(Flags _flags)
335    {
336        assert(flags.isSet(VALID_PADDR|VALID_VADDR));
337        assert(_flags.noneSet(~PUBLIC_FLAGS));
338        flags.clear(_flags);
339    }
340
341    void
342    clearFlags()
343    {
344        assert(flags.isSet(VALID_PADDR|VALID_VADDR));
345        flags.clear(PUBLIC_FLAGS);
346    }
347
348    /** Accessor function for vaddr.*/
349    Addr
350    getVaddr()
351    {
352        assert(flags.isSet(VALID_VADDR));
353        return vaddr;
354    }
355
356    /** Accessor function for asid.*/
357    int
358    getAsid()
359    {
360        assert(flags.isSet(VALID_VADDR));
361        return asid;
362    }
363
364    /** Accessor function for asi.*/
365    uint8_t
366    getAsi()
367    {
368        assert(flags.isSet(VALID_VADDR));
369        return flags & ASI_BITS;
370    }
371
372    /** Accessor function for asi.*/
373    void
374    setAsi(uint8_t a)
375    {
376        assert(flags.isSet(VALID_VADDR));
377        flags.update(a, ASI_BITS);
378    }
379
380    /** Accessor function for asi.*/
381    bool
382    isMmapedIpr()
383    {
384        assert(flags.isSet(VALID_PADDR));
385        return flags.isSet(MMAPED_IPR);
386    }
387
388    /** Accessor function for asi.*/
389    void
390    setMmapedIpr(bool r)
391    {
392        assert(VALID_VADDR);
393        flags.set(MMAPED_IPR);
394    }
395
396    /** Accessor function to check if sc result is valid. */
397    bool
398    extraDataValid()
399    {
400        return flags.isSet(VALID_EXTRA_DATA);
401    }
402
403    /** Accessor function for store conditional return value.*/
404    uint64_t
405    getExtraData() const
406    {
407        assert(flags.isSet(VALID_EXTRA_DATA));
408        return extraData;
409    }
410
411    /** Accessor function for store conditional return value.*/
412    void
413    setExtraData(uint64_t _extraData)
414    {
415        extraData = _extraData;
416        flags.set(VALID_EXTRA_DATA);
417    }
418
419    bool
420    hasContextId() const
421    {
422        return flags.isSet(VALID_CONTEXT_ID);
423    }
424
425    /** Accessor function for context ID.*/
426    int
427    contextId() const
428    {
429        assert(flags.isSet(VALID_CONTEXT_ID));
430        return _contextId;
431    }
432
433    /** Accessor function for thread ID. */
434    int
435    threadId() const
436    {
437        assert(flags.isSet(VALID_THREAD_ID));
438        return _threadId;
439    }
440
441    bool
442    hasPC() const
443    {
444        return flags.isSet(VALID_PC);
445    }
446
447    /** Accessor function for pc.*/
448    Addr
449    getPC() const
450    {
451        assert(flags.isSet(VALID_PC));
452        return pc;
453    }
454
455    /** Accessor Function to Check Cacheability. */
456    bool isUncacheable() const { return flags.isSet(UNCACHEABLE); }
457    bool isInstRead() const { return flags.isSet(INST_READ); }
458    bool isLLSC() const { return flags.isSet(LLSC); }
459    bool isLocked() const { return flags.isSet(LOCKED); }
460    bool isSwap() const { return flags.isSet(MEM_SWAP|MEM_SWAP_COND); }
461    bool isCondSwap() const { return flags.isSet(MEM_SWAP_COND); }
462
463    bool
464    isMisaligned() const
465    {
466        if (flags.isSet(NO_ALIGN_FAULT))
467            return false;
468
469        if ((vaddr & 0x1))
470            return true;
471
472        if (flags.isSet(NO_HALF_WORD_ALIGN_FAULT))
473            return false;
474
475        if ((vaddr & 0x2))
476            return true;
477
478        return false;
479    }
480};
481
482#endif // __MEM_REQUEST_HH__
483