request.hh revision 10823:64cd1dcd61a5 
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 to an uncacheable address. */
105    static const FlagsType UNCACHEABLE                 = 0x00001000;
106    /** This request is to a memory mapped register. */
107    static const FlagsType MMAPPED_IPR                 = 0x00002000;
108    /** This request is a clear exclusive. */
109    static const FlagsType CLEAR_LL                    = 0x00004000;
110    /** This request is made in privileged mode. */
111    static const FlagsType PRIVILEGED                  = 0x00008000;
112
113    /** This is a write that is targeted and zeroing an entire cache block.
114     * There is no need for a read/modify/write
115     */
116    static const FlagsType CACHE_BLOCK_ZERO            = 0x00010000;
117
118    /** The request should not cause a memory access. */
119    static const FlagsType NO_ACCESS                   = 0x00080000;
120    /** This request will lock or unlock the accessed memory. When used with
121     * a load, the access locks the particular chunk of memory. When used
122     * with a store, it unlocks. The rule is that locked accesses have to be
123     * made up of a locked load, some operation on the data, and then a locked
124     * store.
125     */
126    static const FlagsType LOCKED_RMW                  = 0x00100000;
127    /** The request is a Load locked/store conditional. */
128    static const FlagsType LLSC                        = 0x00200000;
129    /** This request is for a memory swap. */
130    static const FlagsType MEM_SWAP                    = 0x00400000;
131    static const FlagsType MEM_SWAP_COND               = 0x00800000;
132
133    /** The request is a prefetch. */
134    static const FlagsType PREFETCH                    = 0x01000000;
135    /** The request should be prefetched into the exclusive state. */
136    static const FlagsType PF_EXCLUSIVE                = 0x02000000;
137    /** The request should be marked as LRU. */
138    static const FlagsType EVICT_NEXT                  = 0x04000000;
139
140    /** The request should be handled by the generic IPR code (only
141     * valid together with MMAPPED_IPR) */
142    static const FlagsType GENERIC_IPR                 = 0x08000000;
143
144    /** The request targets the secure memory space. */
145    static const FlagsType SECURE                      = 0x10000000;
146    /** The request is a page table walk */
147    static const FlagsType PT_WALK                     = 0x20000000;
148
149    /** These flags are *not* cleared when a Request object is reused
150       (assigned a new address). */
151    static const FlagsType STICKY_FLAGS = INST_FETCH;
152
153    /** Request Ids that are statically allocated
154     * @{*/
155    /** This request id is used for writeback requests by the caches */
156    static const MasterID wbMasterId = 0;
157    /** This request id is used for functional requests that don't come from a
158     * particular device
159     */
160    static const MasterID funcMasterId = 1;
161    /** This request id is used for message signaled interrupts */
162    static const MasterID intMasterId = 2;
163    /** Invalid request id for assertion checking only. It is invalid behavior
164     * to ever send this id as part of a request.
165     * @todo C++1x replace with numeric_limits when constexpr is added  */
166    static const MasterID invldMasterId = std::numeric_limits<MasterID>::max();
167    /** @} */
168
169    /** Invalid or unknown Pid. Possible when operating system is not present
170     *  or has not assigned a pid yet */
171    static const uint32_t invldPid = std::numeric_limits<uint32_t>::max();
172
173  private:
174    typedef uint8_t PrivateFlagsType;
175    typedef ::Flags<PrivateFlagsType> PrivateFlags;
176
177    /** Whether or not the size is valid. */
178    static const PrivateFlagsType VALID_SIZE           = 0x00000001;
179    /** Whether or not paddr is valid (has been written yet). */
180    static const PrivateFlagsType VALID_PADDR          = 0x00000002;
181    /** Whether or not the vaddr & asid are valid. */
182    static const PrivateFlagsType VALID_VADDR          = 0x00000004;
183    /** Whether or not the pc is valid. */
184    static const PrivateFlagsType VALID_PC             = 0x00000010;
185    /** Whether or not the context ID is valid. */
186    static const PrivateFlagsType VALID_CONTEXT_ID     = 0x00000020;
187    static const PrivateFlagsType VALID_THREAD_ID      = 0x00000040;
188    /** Whether or not the sc result is valid. */
189    static const PrivateFlagsType VALID_EXTRA_DATA     = 0x00000080;
190
191    /** These flags are *not* cleared when a Request object is reused
192       (assigned a new address). */
193    static const PrivateFlagsType STICKY_PRIVATE_FLAGS =
194        VALID_CONTEXT_ID | VALID_THREAD_ID;
195
196  private:
197
198    /**
199     * Set up a physical (e.g. device) request in a previously
200     * allocated Request object.
201     */
202    void
203    setPhys(Addr paddr, unsigned size, Flags flags, MasterID mid, Tick time)
204    {
205        assert(size >= 0);
206        _paddr = paddr;
207        _size = size;
208        _time = time;
209        _masterId = mid;
210        _flags.clear(~STICKY_FLAGS);
211        _flags.set(flags);
212        privateFlags.clear(~STICKY_PRIVATE_FLAGS);
213        privateFlags.set(VALID_PADDR|VALID_SIZE);
214        depth = 0;
215        accessDelta = 0;
216        //translateDelta = 0;
217    }
218
219    /**
220     * The physical address of the request. Valid only if validPaddr
221     * is set.
222     */
223    Addr _paddr;
224
225    /**
226     * The size of the request. This field must be set when vaddr or
227     * paddr is written via setVirt() or setPhys(), so it is always
228     * valid as long as one of the address fields is valid.
229     */
230    unsigned _size;
231
232    /** The requestor ID which is unique in the system for all ports
233     * that are capable of issuing a transaction
234     */
235    MasterID _masterId;
236
237    /** Flag structure for the request. */
238    Flags _flags;
239
240    /** Private flags for field validity checking. */
241    PrivateFlags privateFlags;
242
243    /**
244     * The time this request was started. Used to calculate
245     * latencies. This field is set to curTick() any time paddr or vaddr
246     * is written.
247     */
248    Tick _time;
249
250    /**
251     * The task id associated with this request
252     */
253    uint32_t _taskId;
254
255    /** The address space ID. */
256    int _asid;
257
258    /** The virtual address of the request. */
259    Addr _vaddr;
260
261    /**
262     * Extra data for the request, such as the return value of
263     * store conditional or the compare value for a CAS. */
264    uint64_t _extraData;
265
266    /** The context ID (for statistics, typically). */
267    int _contextId;
268    /** The thread ID (id within this CPU) */
269    ThreadID _threadId;
270
271    /** program counter of initiating access; for tracing/debugging */
272    Addr _pc;
273
274  public:
275
276    /**
277     * Minimal constructor. No fields are initialized. (Note that
278     *  _flags and privateFlags are cleared by Flags default
279     *  constructor.)
280     */
281    Request()
282        : _paddr(0), _size(0), _masterId(invldMasterId), _time(0),
283          _taskId(ContextSwitchTaskId::Unknown), _asid(0), _vaddr(0),
284          _extraData(0), _contextId(0), _threadId(0), _pc(0),
285          translateDelta(0), accessDelta(0), depth(0)
286    {}
287
288    /**
289     * Constructor for physical (e.g. device) requests.  Initializes
290     * just physical address, size, flags, and timestamp (to curTick()).
291     * These fields are adequate to perform a request.
292     */
293    Request(Addr paddr, unsigned size, Flags flags, MasterID mid)
294        : _paddr(0), _size(0), _masterId(invldMasterId), _time(0),
295          _taskId(ContextSwitchTaskId::Unknown), _asid(0), _vaddr(0),
296          _extraData(0), _contextId(0), _threadId(0), _pc(0),
297          translateDelta(0), accessDelta(0), depth(0)
298    {
299        setPhys(paddr, size, flags, mid, curTick());
300    }
301
302    Request(Addr paddr, unsigned size, Flags flags, MasterID mid, Tick time)
303        : _paddr(0), _size(0), _masterId(invldMasterId), _time(0),
304          _taskId(ContextSwitchTaskId::Unknown), _asid(0), _vaddr(0),
305          _extraData(0), _contextId(0), _threadId(0), _pc(0),
306          translateDelta(0), accessDelta(0), depth(0)
307    {
308        setPhys(paddr, size, flags, mid, time);
309    }
310
311    Request(Addr paddr, unsigned size, Flags flags, MasterID mid, Tick time,
312            Addr pc)
313        : _paddr(0), _size(0), _masterId(invldMasterId), _time(0),
314          _taskId(ContextSwitchTaskId::Unknown), _asid(0), _vaddr(0),
315          _extraData(0), _contextId(0), _threadId(0), _pc(0),
316          translateDelta(0), accessDelta(0), depth(0)
317    {
318        setPhys(paddr, size, flags, mid, time);
319        privateFlags.set(VALID_PC);
320        _pc = pc;
321    }
322
323    Request(int asid, Addr vaddr, unsigned size, Flags flags, MasterID mid,
324            Addr pc, int cid, ThreadID tid)
325        : _paddr(0), _size(0), _masterId(invldMasterId), _time(0),
326          _taskId(ContextSwitchTaskId::Unknown), _asid(0), _vaddr(0),
327          _extraData(0), _contextId(0), _threadId(0), _pc(0),
328          translateDelta(0), accessDelta(0), depth(0)
329    {
330        setVirt(asid, vaddr, size, flags, mid, pc);
331        setThreadContext(cid, tid);
332    }
333
334    ~Request() {}
335
336    /**
337     * Set up CPU and thread numbers.
338     */
339    void
340    setThreadContext(int context_id, ThreadID tid)
341    {
342        _contextId = context_id;
343        _threadId = tid;
344        privateFlags.set(VALID_CONTEXT_ID|VALID_THREAD_ID);
345    }
346
347    /**
348     * Set up a virtual (e.g., CPU) request in a previously
349     * allocated Request object.
350     */
351    void
352    setVirt(int asid, Addr vaddr, unsigned size, Flags flags, MasterID mid,
353            Addr pc)
354    {
355        _asid = asid;
356        _vaddr = vaddr;
357        _size = size;
358        _masterId = mid;
359        _pc = pc;
360        _time = curTick();
361
362        _flags.clear(~STICKY_FLAGS);
363        _flags.set(flags);
364        privateFlags.clear(~STICKY_PRIVATE_FLAGS);
365        privateFlags.set(VALID_VADDR|VALID_SIZE|VALID_PC);
366        depth = 0;
367        accessDelta = 0;
368        translateDelta = 0;
369    }
370
371    /**
372     * Set just the physical address.  This usually used to record the
373     * result of a translation. However, when using virtualized CPUs
374     * setPhys() is sometimes called to finalize a physical address
375     * without a virtual address, so we can't check if the virtual
376     * address is valid.
377     */
378    void
379    setPaddr(Addr paddr)
380    {
381        _paddr = paddr;
382        privateFlags.set(VALID_PADDR);
383    }
384
385    /**
386     * Generate two requests as if this request had been split into two
387     * pieces. The original request can't have been translated already.
388     */
389    void splitOnVaddr(Addr split_addr, RequestPtr &req1, RequestPtr &req2)
390    {
391        assert(privateFlags.isSet(VALID_VADDR));
392        assert(privateFlags.noneSet(VALID_PADDR));
393        assert(split_addr > _vaddr && split_addr < _vaddr + _size);
394        req1 = new Request(*this);
395        req2 = new Request(*this);
396        req1->_size = split_addr - _vaddr;
397        req2->_vaddr = split_addr;
398        req2->_size = _size - req1->_size;
399    }
400
401    /**
402     * Accessor for paddr.
403     */
404    bool
405    hasPaddr() const
406    {
407        return privateFlags.isSet(VALID_PADDR);
408    }
409
410    Addr
411    getPaddr() const
412    {
413        assert(privateFlags.isSet(VALID_PADDR));
414        return _paddr;
415    }
416
417    /**
418     * Time for the TLB/table walker to successfully translate this request.
419     */
420    Tick translateDelta;
421
422    /**
423     * Access latency to complete this memory transaction not including
424     * translation time.
425     */
426    Tick accessDelta;
427
428    /**
429     * Level of the cache hierachy where this request was responded to
430     * (e.g. 0 = L1; 1 = L2).
431     */
432    mutable int depth;
433
434    /**
435     *  Accessor for size.
436     */
437    bool
438    hasSize() const
439    {
440        return privateFlags.isSet(VALID_SIZE);
441    }
442
443    unsigned
444    getSize() const
445    {
446        assert(privateFlags.isSet(VALID_SIZE));
447        return _size;
448    }
449
450    /** Accessor for time. */
451    Tick
452    time() const
453    {
454        assert(privateFlags.isSet(VALID_PADDR|VALID_VADDR));
455        return _time;
456    }
457
458    /** Accessor for flags. */
459    Flags
460    getFlags()
461    {
462        assert(privateFlags.isSet(VALID_PADDR|VALID_VADDR));
463        return _flags;
464    }
465
466    /** Note that unlike other accessors, this function sets *specific
467       flags* (ORs them in); it does not assign its argument to the
468       _flags field.  Thus this method should rightly be called
469       setFlags() and not just flags(). */
470    void
471    setFlags(Flags flags)
472    {
473        assert(privateFlags.isSet(VALID_PADDR|VALID_VADDR));
474        _flags.set(flags);
475    }
476
477    /** Accessor function for vaddr.*/
478    bool
479    hasVaddr() const
480    {
481        return privateFlags.isSet(VALID_VADDR);
482    }
483
484    Addr
485    getVaddr() const
486    {
487        assert(privateFlags.isSet(VALID_VADDR));
488        return _vaddr;
489    }
490
491    /** Accesssor for the requestor id. */
492    MasterID
493    masterId() const
494    {
495        return _masterId;
496    }
497
498    uint32_t
499    taskId() const
500    {
501        return _taskId;
502    }
503
504    void
505    taskId(uint32_t id) {
506        _taskId = id;
507    }
508
509    /** Accessor function for asid.*/
510    int
511    getAsid() const
512    {
513        assert(privateFlags.isSet(VALID_VADDR));
514        return _asid;
515    }
516
517    /** Accessor function for asid.*/
518    void
519    setAsid(int asid)
520    {
521        _asid = asid;
522    }
523
524    /** Accessor function for architecture-specific flags.*/
525    ArchFlagsType
526    getArchFlags() const
527    {
528        assert(privateFlags.isSet(VALID_PADDR|VALID_VADDR));
529        return _flags & ARCH_BITS;
530    }
531
532    /** Accessor function to check if sc result is valid. */
533    bool
534    extraDataValid() const
535    {
536        return privateFlags.isSet(VALID_EXTRA_DATA);
537    }
538
539    /** Accessor function for store conditional return value.*/
540    uint64_t
541    getExtraData() const
542    {
543        assert(privateFlags.isSet(VALID_EXTRA_DATA));
544        return _extraData;
545    }
546
547    /** Accessor function for store conditional return value.*/
548    void
549    setExtraData(uint64_t extraData)
550    {
551        _extraData = extraData;
552        privateFlags.set(VALID_EXTRA_DATA);
553    }
554
555    bool
556    hasContextId() const
557    {
558        return privateFlags.isSet(VALID_CONTEXT_ID);
559    }
560
561    /** Accessor function for context ID.*/
562    int
563    contextId() const
564    {
565        assert(privateFlags.isSet(VALID_CONTEXT_ID));
566        return _contextId;
567    }
568
569    /** Accessor function for thread ID. */
570    ThreadID
571    threadId() const
572    {
573        assert(privateFlags.isSet(VALID_THREAD_ID));
574        return _threadId;
575    }
576
577    void
578    setPC(Addr pc)
579    {
580        privateFlags.set(VALID_PC);
581        _pc = pc;
582    }
583
584    bool
585    hasPC() const
586    {
587        return privateFlags.isSet(VALID_PC);
588    }
589
590    /** Accessor function for pc.*/
591    Addr
592    getPC() const
593    {
594        assert(privateFlags.isSet(VALID_PC));
595        return _pc;
596    }
597
598    /**
599     * Increment/Get the depth at which this request is responded to.
600     * This currently happens when the request misses in any cache level.
601     */
602    void incAccessDepth() const { depth++; }
603    int getAccessDepth() const { return depth; }
604
605    /**
606     * Set/Get the time taken for this request to be successfully translated.
607     */
608    void setTranslateLatency() { translateDelta = curTick() - _time; }
609    Tick getTranslateLatency() const { return translateDelta; }
610
611    /**
612     * Set/Get the time taken to complete this request's access, not including
613     *  the time to successfully translate the request.
614     */
615    void setAccessLatency() { accessDelta = curTick() - _time - translateDelta; }
616    Tick getAccessLatency() const { return accessDelta; }
617
618    /** Accessor functions for flags.  Note that these are for testing
619       only; setting flags should be done via setFlags(). */
620    bool isUncacheable() const { return _flags.isSet(UNCACHEABLE); }
621    bool isInstFetch() const { return _flags.isSet(INST_FETCH); }
622    bool isPrefetch() const { return _flags.isSet(PREFETCH); }
623    bool isLLSC() const { return _flags.isSet(LLSC); }
624    bool isPriv() const { return _flags.isSet(PRIVILEGED); }
625    bool isLockedRMW() const { return _flags.isSet(LOCKED_RMW); }
626    bool isSwap() const { return _flags.isSet(MEM_SWAP|MEM_SWAP_COND); }
627    bool isCondSwap() const { return _flags.isSet(MEM_SWAP_COND); }
628    bool isMmappedIpr() const { return _flags.isSet(MMAPPED_IPR); }
629    bool isClearLL() const { return _flags.isSet(CLEAR_LL); }
630    bool isSecure() const { return _flags.isSet(SECURE); }
631    bool isPTWalk() const { return _flags.isSet(PT_WALK); }
632};
633
634#endif // __MEM_REQUEST_HH__
635