request.hh revision 10568:e70523bd0d26 
1/*
2 * Copyright (c) 2012-2013 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    /** This is a write that is targeted and zeroing an entire cache block.
118     * There is no need for a read/modify/write
119     */
120    static const FlagsType CACHE_BLOCK_ZERO            = 0x00010000;
121
122    /** The request should not cause a memory access. */
123    static const FlagsType NO_ACCESS                   = 0x00080000;
124    /** This request will lock or unlock the accessed memory. When used with
125     * a load, the access locks the particular chunk of memory. When used
126     * with a store, it unlocks. The rule is that locked accesses have to be
127     * made up of a locked load, some operation on the data, and then a locked
128     * store.
129     */
130    static const FlagsType LOCKED                      = 0x00100000;
131    /** The request is a Load locked/store conditional. */
132    static const FlagsType LLSC                        = 0x00200000;
133    /** This request is for a memory swap. */
134    static const FlagsType MEM_SWAP                    = 0x00400000;
135    static const FlagsType MEM_SWAP_COND               = 0x00800000;
136
137    /** The request is a prefetch. */
138    static const FlagsType PREFETCH                    = 0x01000000;
139    /** The request should be prefetched into the exclusive state. */
140    static const FlagsType PF_EXCLUSIVE                = 0x02000000;
141    /** The request should be marked as LRU. */
142    static const FlagsType EVICT_NEXT                  = 0x04000000;
143
144    /** The request should be handled by the generic IPR code (only
145     * valid together with MMAPPED_IPR) */
146    static const FlagsType GENERIC_IPR                 = 0x08000000;
147
148    /** The request targets the secure memory space. */
149    static const FlagsType SECURE                      = 0x10000000;
150    /** The request is a page table walk */
151    static const FlagsType PT_WALK                     = 0x20000000;
152
153    /** These flags are *not* cleared when a Request object is reused
154       (assigned a new address). */
155    static const FlagsType STICKY_FLAGS = INST_FETCH;
156
157    /** Request Ids that are statically allocated
158     * @{*/
159    /** This request id is used for writeback requests by the caches */
160    static const MasterID wbMasterId = 0;
161    /** This request id is used for functional requests that don't come from a
162     * particular device
163     */
164    static const MasterID funcMasterId = 1;
165    /** This request id is used for message signaled interrupts */
166    static const MasterID intMasterId = 2;
167    /** Invalid request id for assertion checking only. It is invalid behavior
168     * to ever send this id as part of a request.
169     * @todo C++1x replace with numeric_limits when constexpr is added  */
170    static const MasterID invldMasterId = USHRT_MAX;
171    /** @} */
172
173    /** Invalid or unknown Pid. Possible when operating system is not present
174     *  or has not assigned a pid yet */
175    static const uint32_t invldPid = UINT_MAX;
176
177  private:
178    typedef uint8_t PrivateFlagsType;
179    typedef ::Flags<PrivateFlagsType> PrivateFlags;
180
181    /** Whether or not the size is valid. */
182    static const PrivateFlagsType VALID_SIZE           = 0x00000001;
183    /** Whether or not paddr is valid (has been written yet). */
184    static const PrivateFlagsType VALID_PADDR          = 0x00000002;
185    /** Whether or not the vaddr & asid are valid. */
186    static const PrivateFlagsType VALID_VADDR          = 0x00000004;
187    /** Whether or not the pc is valid. */
188    static const PrivateFlagsType VALID_PC             = 0x00000010;
189    /** Whether or not the context ID is valid. */
190    static const PrivateFlagsType VALID_CONTEXT_ID     = 0x00000020;
191    static const PrivateFlagsType VALID_THREAD_ID      = 0x00000040;
192    /** Whether or not the sc result is valid. */
193    static const PrivateFlagsType VALID_EXTRA_DATA     = 0x00000080;
194
195    /** These flags are *not* cleared when a Request object is reused
196       (assigned a new address). */
197    static const PrivateFlagsType STICKY_PRIVATE_FLAGS =
198        VALID_CONTEXT_ID | VALID_THREAD_ID;
199
200  private:
201    /**
202     * The physical address of the request. Valid only if validPaddr
203     * is set.
204     */
205    Addr _paddr;
206
207    /**
208     * The size of the request. This field must be set when vaddr or
209     * paddr is written via setVirt() or setPhys(), so it is always
210     * valid as long as one of the address fields is valid.
211     */
212    int _size;
213
214    /** The requestor ID which is unique in the system for all ports
215     * that are capable of issuing a transaction
216     */
217    MasterID _masterId;
218
219    /** Flag structure for the request. */
220    Flags _flags;
221
222    /** Private flags for field validity checking. */
223    PrivateFlags privateFlags;
224
225    /**
226     * The time this request was started. Used to calculate
227     * latencies. This field is set to curTick() any time paddr or vaddr
228     * is written.
229     */
230    Tick _time;
231
232    /**
233     * The task id associated with this request
234     */
235    uint32_t _taskId;
236
237    /** The address space ID. */
238    int _asid;
239
240    /** The virtual address of the request. */
241    Addr _vaddr;
242
243    /**
244     * Extra data for the request, such as the return value of
245     * store conditional or the compare value for a CAS. */
246    uint64_t _extraData;
247
248    /** The context ID (for statistics, typically). */
249    int _contextId;
250    /** The thread ID (id within this CPU) */
251    int _threadId;
252
253    /** program counter of initiating access; for tracing/debugging */
254    Addr _pc;
255
256  public:
257    /** Minimal constructor.  No fields are initialized.
258     *  (Note that _flags and privateFlags are cleared by Flags
259     *  default constructor.)
260     */
261    Request()
262        : _paddr(0), _size(0), _masterId(invldMasterId), _time(0),
263          _taskId(ContextSwitchTaskId::Unknown), _asid(0), _vaddr(0),
264          _extraData(0), _contextId(0), _threadId(0), _pc(0),
265          translateDelta(0), accessDelta(0), depth(0)
266    {}
267
268    /**
269     * Constructor for physical (e.g. device) requests.  Initializes
270     * just physical address, size, flags, and timestamp (to curTick()).
271     * These fields are adequate to perform a request.
272     */
273    Request(Addr paddr, int size, Flags flags, MasterID mid)
274        : _paddr(0), _size(0), _masterId(invldMasterId), _time(0),
275          _taskId(ContextSwitchTaskId::Unknown), _asid(0), _vaddr(0),
276          _extraData(0), _contextId(0), _threadId(0), _pc(0),
277          translateDelta(0), accessDelta(0), depth(0)
278    {
279        setPhys(paddr, size, flags, mid);
280    }
281
282    Request(Addr paddr, int size, Flags flags, MasterID mid, Tick time)
283        : _paddr(0), _size(0), _masterId(invldMasterId), _time(0),
284          _taskId(ContextSwitchTaskId::Unknown), _asid(0), _vaddr(0),
285          _extraData(0), _contextId(0), _threadId(0), _pc(0),
286          translateDelta(0), accessDelta(0), depth(0)
287    {
288        setPhys(paddr, size, flags, mid, time);
289    }
290
291    Request(Addr paddr, int size, Flags flags, MasterID mid, Tick time, Addr pc)
292        : _paddr(0), _size(0), _masterId(invldMasterId), _time(0),
293          _taskId(ContextSwitchTaskId::Unknown), _asid(0), _vaddr(0),
294          _extraData(0), _contextId(0), _threadId(0), _pc(0),
295          translateDelta(0), accessDelta(0), depth(0)
296    {
297        setPhys(paddr, size, flags, mid, time);
298        privateFlags.set(VALID_PC);
299        _pc = pc;
300    }
301
302    Request(int asid, Addr vaddr, int size, Flags flags, MasterID mid, Addr pc,
303            int cid, ThreadID tid)
304        : _paddr(0), _size(0), _masterId(invldMasterId), _time(0),
305          _taskId(ContextSwitchTaskId::Unknown), _asid(0), _vaddr(0),
306          _extraData(0), _contextId(0), _threadId(0), _pc(0),
307          translateDelta(0), accessDelta(0), depth(0)
308    {
309        setVirt(asid, vaddr, size, flags, mid, pc);
310        setThreadContext(cid, tid);
311    }
312
313    ~Request() {}
314
315    /**
316     * Set up CPU and thread numbers.
317     */
318    void
319    setThreadContext(int context_id, ThreadID tid)
320    {
321        _contextId = context_id;
322        _threadId = tid;
323        privateFlags.set(VALID_CONTEXT_ID|VALID_THREAD_ID);
324    }
325
326    /**
327     * Set up a physical (e.g. device) request in a previously
328     * allocated Request object.
329     */
330    void
331    setPhys(Addr paddr, int size, Flags flags, MasterID mid, Tick time)
332    {
333        assert(size >= 0);
334        _paddr = paddr;
335        _size = size;
336        _time = time;
337        _masterId = mid;
338        _flags.clear(~STICKY_FLAGS);
339        _flags.set(flags);
340        privateFlags.clear(~STICKY_PRIVATE_FLAGS);
341        privateFlags.set(VALID_PADDR|VALID_SIZE);
342        depth = 0;
343        accessDelta = 0;
344        //translateDelta = 0;
345    }
346
347    void
348    setPhys(Addr paddr, int size, Flags flags, MasterID mid)
349    {
350        setPhys(paddr, size, flags, mid, curTick());
351    }
352
353    /**
354     * Set up a virtual (e.g., CPU) request in a previously
355     * allocated Request object.
356     */
357    void
358    setVirt(int asid, Addr vaddr, int size, Flags flags, MasterID mid, Addr pc)
359    {
360        assert(size >= 0);
361        _asid = asid;
362        _vaddr = vaddr;
363        _size = size;
364        _masterId = mid;
365        _pc = pc;
366        _time = curTick();
367
368        _flags.clear(~STICKY_FLAGS);
369        _flags.set(flags);
370        privateFlags.clear(~STICKY_PRIVATE_FLAGS);
371        privateFlags.set(VALID_VADDR|VALID_SIZE|VALID_PC);
372        depth = 0;
373        accessDelta = 0;
374        translateDelta = 0;
375    }
376
377    /**
378     * Set just the physical address.  This usually used to record the
379     * result of a translation. However, when using virtualized CPUs
380     * setPhys() is sometimes called to finalize a physical address
381     * without a virtual address, so we can't check if the virtual
382     * address is valid.
383     */
384    void
385    setPaddr(Addr paddr)
386    {
387        _paddr = paddr;
388        privateFlags.set(VALID_PADDR);
389    }
390
391    /**
392     * Generate two requests as if this request had been split into two
393     * pieces. The original request can't have been translated already.
394     */
395    void splitOnVaddr(Addr split_addr, RequestPtr &req1, RequestPtr &req2)
396    {
397        assert(privateFlags.isSet(VALID_VADDR));
398        assert(privateFlags.noneSet(VALID_PADDR));
399        assert(split_addr > _vaddr && split_addr < _vaddr + _size);
400        req1 = new Request;
401        *req1 = *this;
402        req2 = new Request;
403        *req2 = *this;
404        req1->_size = split_addr - _vaddr;
405        req2->_vaddr = split_addr;
406        req2->_size = _size - req1->_size;
407    }
408
409    /**
410     * Accessor for paddr.
411     */
412    bool
413    hasPaddr() const
414    {
415        return privateFlags.isSet(VALID_PADDR);
416    }
417
418    Addr
419    getPaddr() const
420    {
421        assert(privateFlags.isSet(VALID_PADDR));
422        return _paddr;
423    }
424
425    /**
426     * Time for the TLB/table walker to successfully translate this request.
427     */
428    Tick translateDelta;
429
430    /**
431     * Access latency to complete this memory transaction not including
432     * translation time.
433     */
434    Tick accessDelta;
435
436    /**
437     * Level of the cache hierachy where this request was responded to
438     * (e.g. 0 = L1; 1 = L2).
439     */
440    mutable int depth;
441
442    /**
443     *  Accessor for size.
444     */
445    bool
446    hasSize() const
447    {
448        return privateFlags.isSet(VALID_SIZE);
449    }
450
451    int
452    getSize() const
453    {
454        assert(privateFlags.isSet(VALID_SIZE));
455        return _size;
456    }
457
458    /** Accessor for time. */
459    Tick
460    time() const
461    {
462        assert(privateFlags.isSet(VALID_PADDR|VALID_VADDR));
463        return _time;
464    }
465
466    void
467    time(Tick time)
468    {
469        assert(privateFlags.isSet(VALID_PADDR|VALID_VADDR));
470        _time = time;
471    }
472
473    /** Accessor for flags. */
474    Flags
475    getFlags()
476    {
477        assert(privateFlags.isSet(VALID_PADDR|VALID_VADDR));
478        return _flags;
479    }
480
481    /** Note that unlike other accessors, this function sets *specific
482       flags* (ORs them in); it does not assign its argument to the
483       _flags field.  Thus this method should rightly be called
484       setFlags() and not just flags(). */
485    void
486    setFlags(Flags flags)
487    {
488        assert(privateFlags.isSet(VALID_PADDR|VALID_VADDR));
489        _flags.set(flags);
490    }
491
492    void
493    setArchFlags(Flags flags)
494    {
495        assert(privateFlags.isSet(VALID_PADDR|VALID_VADDR));
496        _flags.set(flags & ARCH_BITS);
497    }
498
499    /** Accessor function for vaddr.*/
500    bool
501    hasVaddr() const
502    {
503        return privateFlags.isSet(VALID_VADDR);
504    }
505
506    Addr
507    getVaddr() const
508    {
509        assert(privateFlags.isSet(VALID_VADDR));
510        return _vaddr;
511    }
512
513    /** Accesssor for the requestor id. */
514    MasterID
515    masterId() const
516    {
517        return _masterId;
518    }
519
520    uint32_t
521    taskId() const
522    {
523        return _taskId;
524    }
525
526    void
527    taskId(uint32_t id) {
528        _taskId = id;
529    }
530
531    /** Accessor function for asid.*/
532    int
533    getAsid() const
534    {
535        assert(privateFlags.isSet(VALID_VADDR));
536        return _asid;
537    }
538
539    /** Accessor function for asid.*/
540    void
541    setAsid(int asid)
542    {
543        _asid = asid;
544    }
545
546    /** Accessor function for architecture-specific flags.*/
547    ArchFlagsType
548    getArchFlags() const
549    {
550        assert(privateFlags.isSet(VALID_PADDR|VALID_VADDR));
551        return _flags & ARCH_BITS;
552    }
553
554    /** Accessor function to check if sc result is valid. */
555    bool
556    extraDataValid() const
557    {
558        return privateFlags.isSet(VALID_EXTRA_DATA);
559    }
560
561    /** Accessor function for store conditional return value.*/
562    uint64_t
563    getExtraData() const
564    {
565        assert(privateFlags.isSet(VALID_EXTRA_DATA));
566        return _extraData;
567    }
568
569    /** Accessor function for store conditional return value.*/
570    void
571    setExtraData(uint64_t extraData)
572    {
573        _extraData = extraData;
574        privateFlags.set(VALID_EXTRA_DATA);
575    }
576
577    bool
578    hasContextId() const
579    {
580        return privateFlags.isSet(VALID_CONTEXT_ID);
581    }
582
583    /** Accessor function for context ID.*/
584    int
585    contextId() const
586    {
587        assert(privateFlags.isSet(VALID_CONTEXT_ID));
588        return _contextId;
589    }
590
591    /** Accessor function for thread ID. */
592    int
593    threadId() const
594    {
595        assert(privateFlags.isSet(VALID_THREAD_ID));
596        return _threadId;
597    }
598
599    void
600    setPC(Addr pc)
601    {
602        privateFlags.set(VALID_PC);
603        _pc = pc;
604    }
605
606    bool
607    hasPC() const
608    {
609        return privateFlags.isSet(VALID_PC);
610    }
611
612    /** Accessor function for pc.*/
613    Addr
614    getPC() const
615    {
616        assert(privateFlags.isSet(VALID_PC));
617        return _pc;
618    }
619
620    /**
621     * Increment/Get the depth at which this request is responded to.
622     * This currently happens when the request misses in any cache level.
623     */
624    void incAccessDepth() const { depth++; }
625    int getAccessDepth() const { return depth; }
626
627    /**
628     * Set/Get the time taken for this request to be successfully translated.
629     */
630    void setTranslateLatency() { translateDelta = curTick() - _time; }
631    Tick getTranslateLatency() const { return translateDelta; }
632
633    /**
634     * Set/Get the time taken to complete this request's access, not including
635     *  the time to successfully translate the request.
636     */
637    void setAccessLatency() { accessDelta = curTick() - _time - translateDelta; }
638    Tick getAccessLatency() const { return accessDelta; }
639
640    /** Accessor functions for flags.  Note that these are for testing
641       only; setting flags should be done via setFlags(). */
642    bool isUncacheable() const { return _flags.isSet(UNCACHEABLE); }
643    bool isInstFetch() const { return _flags.isSet(INST_FETCH); }
644    bool isPrefetch() const { return _flags.isSet(PREFETCH); }
645    bool isLLSC() const { return _flags.isSet(LLSC); }
646    bool isPriv() const { return _flags.isSet(PRIVILEGED); }
647    bool isLocked() const { return _flags.isSet(LOCKED); }
648    bool isSwap() const { return _flags.isSet(MEM_SWAP|MEM_SWAP_COND); }
649    bool isCondSwap() const { return _flags.isSet(MEM_SWAP_COND); }
650    bool isMmappedIpr() const { return _flags.isSet(MMAPPED_IPR); }
651    bool isClearLL() const { return _flags.isSet(CLEAR_LL); }
652    bool isSecure() const { return _flags.isSet(SECURE); }
653    bool isPTWalk() const { return _flags.isSet(PT_WALK); }
654};
655
656#endif // __MEM_REQUEST_HH__
657