request.hh revision 9950:4b7f60080149 
1/*
2 * Copyright (c) 2012 ARM Limited
3 * All rights reserved
4 *
5 * The license below extends only to copyright in the software and shall
6 * not be construed as granting a license to any other intellectual
7 * property including but not limited to intellectual property relating
8 * to a hardware implementation of the functionality of the software
9 * licensed hereunder.  You may use the software subject to the license
10 * terms below provided that you ensure that this notice is replicated
11 * unmodified and in its entirety in all distributions of the software,
12 * modified or unmodified, in source code or in binary form.
13 *
14 * Copyright (c) 2002-2005 The Regents of The University of Michigan
15 * All rights reserved.
16 *
17 * Redistribution and use in source and binary forms, with or without
18 * modification, are permitted provided that the following conditions are
19 * met: redistributions of source code must retain the above copyright
20 * notice, this list of conditions and the following disclaimer;
21 * redistributions in binary form must reproduce the above copyright
22 * notice, this list of conditions and the following disclaimer in the
23 * documentation and/or other materials provided with the distribution;
24 * neither the name of the copyright holders nor the names of its
25 * contributors may be used to endorse or promote products derived from
26 * this software without specific prior written permission.
27 *
28 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
29 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
30 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
31 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
32 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
33 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
34 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
35 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
36 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
37 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
38 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
39 *
40 * Authors: Ron Dreslinski
41 *          Steve Reinhardt
42 *          Ali Saidi
43 */
44
45/**
46 * @file
47 * Declaration of a request, the overall memory request consisting of
48 the parts of the request that are persistent throughout the transaction.
49 */
50
51#ifndef __MEM_REQUEST_HH__
52#define __MEM_REQUEST_HH__
53
54#include <cassert>
55#include <climits>
56
57#include "base/flags.hh"
58#include "base/misc.hh"
59#include "base/types.hh"
60#include "sim/core.hh"
61
62/**
63 * Special TaskIds that are used for per-context-switch stats dumps
64 * and Cache Occupancy. Having too many tasks seems to be a problem
65 * with vector stats. 1024 seems to be a reasonable number that
66 * doesn't cause a problem with stats and is large enough to realistic
67 * benchmarks (Linux/Android boot, BBench, etc.)
68 */
69
70namespace ContextSwitchTaskId {
71    enum TaskId {
72        MaxNormalTaskId = 1021, /* Maximum number of normal tasks */
73        Prefetcher = 1022, /* For cache lines brought in by prefetcher */
74        DMA = 1023, /* Mostly Table Walker */
75        Unknown = 1024,
76        NumTaskId
77    };
78}
79
80class Request;
81
82typedef Request* RequestPtr;
83typedef uint16_t MasterID;
84
85class Request
86{
87  public:
88    typedef uint32_t FlagsType;
89    typedef uint8_t ArchFlagsType;
90    typedef ::Flags<FlagsType> Flags;
91
92    /**
93     * Architecture specific flags.
94     *
95     * These bits int the flag field are reserved for
96     * architecture-specific code. For example, SPARC uses them to
97     * represent ASIs.
98     */
99    static const FlagsType ARCH_BITS                   = 0x000000FF;
100    /** The request was an instruction fetch. */
101    static const FlagsType INST_FETCH                  = 0x00000100;
102    /** The virtual address is also the physical address. */
103    static const FlagsType PHYSICAL                    = 0x00000200;
104    /** The request is an ALPHA VPTE pal access (hw_ld). */
105    static const FlagsType VPTE                        = 0x00000400;
106    /** Use the alternate mode bits in ALPHA. */
107    static const FlagsType ALTMODE                     = 0x00000800;
108    /** The request is to an uncacheable address. */
109    static const FlagsType UNCACHEABLE                 = 0x00001000;
110    /** This request is to a memory mapped register. */
111    static const FlagsType MMAPPED_IPR                  = 0x00002000;
112    /** This request is a clear exclusive. */
113    static const FlagsType CLEAR_LL                    = 0x00004000;
114    /** This request is made in privileged mode. */
115    static const FlagsType PRIVILEGED                   = 0x00008000;
116
117    /** The request should not cause a memory access. */
118    static const FlagsType NO_ACCESS                   = 0x00080000;
119    /** This request will lock or unlock the accessed memory. When used with
120     * a load, the access locks the particular chunk of memory. When used
121     * with a store, it unlocks. The rule is that locked accesses have to be
122     * made up of a locked load, some operation on the data, and then a locked
123     * store.
124     */
125    static const FlagsType LOCKED                      = 0x00100000;
126    /** The request is a Load locked/store conditional. */
127    static const FlagsType LLSC                        = 0x00200000;
128    /** This request is for a memory swap. */
129    static const FlagsType MEM_SWAP                    = 0x00400000;
130    static const FlagsType MEM_SWAP_COND               = 0x00800000;
131
132    /** The request is a prefetch. */
133    static const FlagsType PREFETCH                    = 0x01000000;
134    /** The request should be prefetched into the exclusive state. */
135    static const FlagsType PF_EXCLUSIVE                = 0x02000000;
136    /** The request should be marked as LRU. */
137    static const FlagsType EVICT_NEXT                  = 0x04000000;
138
139    /** The request should be handled by the generic IPR code (only
140     * valid together with MMAPPED_IPR) */
141    static const FlagsType GENERIC_IPR                 = 0x08000000;
142
143    /** These flags are *not* cleared when a Request object is reused
144       (assigned a new address). */
145    static const FlagsType STICKY_FLAGS = INST_FETCH;
146
147    /** Request Ids that are statically allocated
148     * @{*/
149    /** This request id is used for writeback requests by the caches */
150    static const MasterID wbMasterId = 0;
151    /** This request id is used for functional requests that don't come from a
152     * particular device
153     */
154    static const MasterID funcMasterId = 1;
155    /** This request id is used for message signaled interrupts */
156    static const MasterID intMasterId = 2;
157    /** Invalid request id for assertion checking only. It is invalid behavior
158     * to ever send this id as part of a request.
159     * @todo C++1x replace with numeric_limits when constexpr is added  */
160    static const MasterID invldMasterId = USHRT_MAX;
161    /** @} */
162
163    /** Invalid or unknown Pid. Possible when operating system is not present
164     *  or has not assigned a pid yet */
165    static const uint32_t invldPid = UINT_MAX;
166
167  private:
168    typedef uint8_t PrivateFlagsType;
169    typedef ::Flags<PrivateFlagsType> PrivateFlags;
170
171    /** Whether or not the size is valid. */
172    static const PrivateFlagsType VALID_SIZE           = 0x00000001;
173    /** Whether or not paddr is valid (has been written yet). */
174    static const PrivateFlagsType VALID_PADDR          = 0x00000002;
175    /** Whether or not the vaddr & asid are valid. */
176    static const PrivateFlagsType VALID_VADDR          = 0x00000004;
177    /** Whether or not the pc is valid. */
178    static const PrivateFlagsType VALID_PC             = 0x00000010;
179    /** Whether or not the context ID is valid. */
180    static const PrivateFlagsType VALID_CONTEXT_ID     = 0x00000020;
181    static const PrivateFlagsType VALID_THREAD_ID      = 0x00000040;
182    /** Whether or not the sc result is valid. */
183    static const PrivateFlagsType VALID_EXTRA_DATA     = 0x00000080;
184
185    /** These flags are *not* cleared when a Request object is reused
186       (assigned a new address). */
187    static const PrivateFlagsType STICKY_PRIVATE_FLAGS =
188        VALID_CONTEXT_ID | VALID_THREAD_ID;
189
190  private:
191    /**
192     * The physical address of the request. Valid only if validPaddr
193     * is set.
194     */
195    Addr _paddr;
196
197    /**
198     * The size of the request. This field must be set when vaddr or
199     * paddr is written via setVirt() or setPhys(), so it is always
200     * valid as long as one of the address fields is valid.
201     */
202    int _size;
203
204    /** The requestor ID which is unique in the system for all ports
205     * that are capable of issuing a transaction
206     */
207    MasterID _masterId;
208
209    /** Flag structure for the request. */
210    Flags _flags;
211
212    /** Private flags for field validity checking. */
213    PrivateFlags privateFlags;
214
215    /**
216     * The time this request was started. Used to calculate
217     * latencies. This field is set to curTick() any time paddr or vaddr
218     * is written.
219     */
220    Tick _time;
221
222    /** The address space ID. */
223    int _asid;
224
225    /** The virtual address of the request. */
226    Addr _vaddr;
227
228    /**
229     * Extra data for the request, such as the return value of
230     * store conditional or the compare value for a CAS. */
231    uint64_t _extraData;
232
233    /** The context ID (for statistics, typically). */
234    int _contextId;
235    /** The thread ID (id within this CPU) */
236    int _threadId;
237
238    /** program counter of initiating access; for tracing/debugging */
239    Addr _pc;
240
241  public:
242    /** Minimal constructor.  No fields are initialized.
243     *  (Note that _flags and privateFlags are cleared by Flags
244     *  default constructor.)
245     */
246    Request()
247    {}
248
249    /**
250     * Constructor for physical (e.g. device) requests.  Initializes
251     * just physical address, size, flags, and timestamp (to curTick()).
252     * These fields are adequate to perform a request.
253     */
254    Request(Addr paddr, int size, Flags flags, MasterID mid)
255    {
256        setPhys(paddr, size, flags, mid);
257    }
258
259    Request(Addr paddr, int size, Flags flags, MasterID mid, Tick time)
260    {
261        setPhys(paddr, size, flags, mid, time);
262    }
263
264    Request(Addr paddr, int size, Flags flags, MasterID mid, Tick time, Addr pc)
265    {
266        setPhys(paddr, size, flags, mid, time);
267        privateFlags.set(VALID_PC);
268        _pc = pc;
269    }
270
271    Request(int asid, Addr vaddr, int size, Flags flags, MasterID mid, Addr pc,
272            int cid, ThreadID tid)
273    {
274        setVirt(asid, vaddr, size, flags, mid, pc);
275        setThreadContext(cid, tid);
276    }
277
278    ~Request() {}
279
280    /**
281     * Set up CPU and thread numbers.
282     */
283    void
284    setThreadContext(int context_id, ThreadID tid)
285    {
286        _contextId = context_id;
287        _threadId = tid;
288        privateFlags.set(VALID_CONTEXT_ID|VALID_THREAD_ID);
289    }
290
291    /**
292     * Set up a physical (e.g. device) request in a previously
293     * allocated Request object.
294     */
295    void
296    setPhys(Addr paddr, int size, Flags flags, MasterID mid, Tick time)
297    {
298        assert(size >= 0);
299        _paddr = paddr;
300        _size = size;
301        _time = time;
302        _masterId = mid;
303        _flags.clear(~STICKY_FLAGS);
304        _flags.set(flags);
305        privateFlags.clear(~STICKY_PRIVATE_FLAGS);
306        privateFlags.set(VALID_PADDR|VALID_SIZE);
307    }
308
309    void
310    setPhys(Addr paddr, int size, Flags flags, MasterID mid)
311    {
312        setPhys(paddr, size, flags, mid, curTick());
313    }
314
315    /**
316     * Set up a virtual (e.g., CPU) request in a previously
317     * allocated Request object.
318     */
319    void
320    setVirt(int asid, Addr vaddr, int size, Flags flags, MasterID mid, Addr pc)
321    {
322        assert(size >= 0);
323        _asid = asid;
324        _vaddr = vaddr;
325        _size = size;
326        _masterId = mid;
327        _pc = pc;
328        _time = curTick();
329
330        _flags.clear(~STICKY_FLAGS);
331        _flags.set(flags);
332        privateFlags.clear(~STICKY_PRIVATE_FLAGS);
333        privateFlags.set(VALID_VADDR|VALID_SIZE|VALID_PC);
334    }
335
336    /**
337     * Set just the physical address.  This usually used to record the
338     * result of a translation. However, when using virtualized CPUs
339     * setPhys() is sometimes called to finalize a physical address
340     * without a virtual address, so we can't check if the virtual
341     * address is valid.
342     */
343    void
344    setPaddr(Addr paddr)
345    {
346        _paddr = paddr;
347        privateFlags.set(VALID_PADDR);
348    }
349
350    /**
351     * Generate two requests as if this request had been split into two
352     * pieces. The original request can't have been translated already.
353     */
354    void splitOnVaddr(Addr split_addr, RequestPtr &req1, RequestPtr &req2)
355    {
356        assert(privateFlags.isSet(VALID_VADDR));
357        assert(privateFlags.noneSet(VALID_PADDR));
358        assert(split_addr > _vaddr && split_addr < _vaddr + _size);
359        req1 = new Request;
360        *req1 = *this;
361        req2 = new Request;
362        *req2 = *this;
363        req1->_size = split_addr - _vaddr;
364        req2->_vaddr = split_addr;
365        req2->_size = _size - req1->_size;
366    }
367
368    /**
369     * Accessor for paddr.
370     */
371    bool
372    hasPaddr()
373    {
374        return privateFlags.isSet(VALID_PADDR);
375    }
376
377    Addr
378    getPaddr()
379    {
380        assert(privateFlags.isSet(VALID_PADDR));
381        return _paddr;
382    }
383
384    /**
385     *  Accessor for size.
386     */
387    bool
388    hasSize()
389    {
390        return privateFlags.isSet(VALID_SIZE);
391    }
392
393    int
394    getSize()
395    {
396        assert(privateFlags.isSet(VALID_SIZE));
397        return _size;
398    }
399
400    /** Accessor for time. */
401    Tick
402    time() const
403    {
404        assert(privateFlags.isSet(VALID_PADDR|VALID_VADDR));
405        return _time;
406    }
407
408    void
409    time(Tick time)
410    {
411        assert(privateFlags.isSet(VALID_PADDR|VALID_VADDR));
412        _time = time;
413    }
414
415    /** Accessor for flags. */
416    Flags
417    getFlags()
418    {
419        assert(privateFlags.isSet(VALID_PADDR|VALID_VADDR));
420        return _flags;
421    }
422
423    /** Note that unlike other accessors, this function sets *specific
424       flags* (ORs them in); it does not assign its argument to the
425       _flags field.  Thus this method should rightly be called
426       setFlags() and not just flags(). */
427    void
428    setFlags(Flags flags)
429    {
430        assert(privateFlags.isSet(VALID_PADDR|VALID_VADDR));
431        _flags.set(flags);
432    }
433
434    void
435    setArchFlags(Flags flags)
436    {
437        assert(privateFlags.isSet(VALID_PADDR|VALID_VADDR));
438        _flags.set(flags & ARCH_BITS);
439    }
440
441    /** Accessor function for vaddr.*/
442    Addr
443    getVaddr()
444    {
445        assert(privateFlags.isSet(VALID_VADDR));
446        return _vaddr;
447    }
448
449    /** Accesssor for the requestor id. */
450    MasterID
451    masterId()
452    {
453        return _masterId;
454    }
455
456    /** Accessor function for asid.*/
457    int
458    getAsid()
459    {
460        assert(privateFlags.isSet(VALID_VADDR));
461        return _asid;
462    }
463
464    /** Accessor function for asid.*/
465    void
466    setAsid(int asid)
467    {
468        _asid = asid;
469    }
470
471    /** Accessor function for architecture-specific flags.*/
472    ArchFlagsType
473    getArchFlags()
474    {
475        assert(privateFlags.isSet(VALID_PADDR|VALID_VADDR));
476        return _flags & ARCH_BITS;
477    }
478
479    /** Accessor function to check if sc result is valid. */
480    bool
481    extraDataValid()
482    {
483        return privateFlags.isSet(VALID_EXTRA_DATA);
484    }
485
486    /** Accessor function for store conditional return value.*/
487    uint64_t
488    getExtraData() const
489    {
490        assert(privateFlags.isSet(VALID_EXTRA_DATA));
491        return _extraData;
492    }
493
494    /** Accessor function for store conditional return value.*/
495    void
496    setExtraData(uint64_t extraData)
497    {
498        _extraData = extraData;
499        privateFlags.set(VALID_EXTRA_DATA);
500    }
501
502    bool
503    hasContextId() const
504    {
505        return privateFlags.isSet(VALID_CONTEXT_ID);
506    }
507
508    /** Accessor function for context ID.*/
509    int
510    contextId() const
511    {
512        assert(privateFlags.isSet(VALID_CONTEXT_ID));
513        return _contextId;
514    }
515
516    /** Accessor function for thread ID. */
517    int
518    threadId() const
519    {
520        assert(privateFlags.isSet(VALID_THREAD_ID));
521        return _threadId;
522    }
523
524    bool
525    hasPC() const
526    {
527        return privateFlags.isSet(VALID_PC);
528    }
529
530    /** Accessor function for pc.*/
531    Addr
532    getPC() const
533    {
534        assert(privateFlags.isSet(VALID_PC));
535        return _pc;
536    }
537
538    /** Accessor functions for flags.  Note that these are for testing
539       only; setting flags should be done via setFlags(). */
540    bool isUncacheable() const { return _flags.isSet(UNCACHEABLE); }
541    bool isInstFetch() const { return _flags.isSet(INST_FETCH); }
542    bool isPrefetch() const { return _flags.isSet(PREFETCH); }
543    bool isLLSC() const { return _flags.isSet(LLSC); }
544    bool isPriv() const { return _flags.isSet(PRIVILEGED); }
545    bool isLocked() const { return _flags.isSet(LOCKED); }
546    bool isSwap() const { return _flags.isSet(MEM_SWAP|MEM_SWAP_COND); }
547    bool isCondSwap() const { return _flags.isSet(MEM_SWAP_COND); }
548    bool isMmappedIpr() const { return _flags.isSet(MMAPPED_IPR); }
549    bool isClearLL() const { return _flags.isSet(CLEAR_LL); }
550};
551
552#endif // __MEM_REQUEST_HH__
553