request.hh revision 10052 
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        : _taskId(ContextSwitchTaskId::Unknown),
263        translateDelta(0), accessDelta(0), depth(0)
264    {}
265
266    /**
267     * Constructor for physical (e.g. device) requests.  Initializes
268     * just physical address, size, flags, and timestamp (to curTick()).
269     * These fields are adequate to perform a request.
270     */
271    Request(Addr paddr, int size, Flags flags, MasterID mid)
272        : _taskId(ContextSwitchTaskId::Unknown)
273    {
274        setPhys(paddr, size, flags, mid);
275    }
276
277    Request(Addr paddr, int size, Flags flags, MasterID mid, Tick time)
278        : _taskId(ContextSwitchTaskId::Unknown)
279    {
280        setPhys(paddr, size, flags, mid, time);
281    }
282
283    Request(Addr paddr, int size, Flags flags, MasterID mid, Tick time, Addr pc)
284        : _taskId(ContextSwitchTaskId::Unknown)
285    {
286        setPhys(paddr, size, flags, mid, time);
287        privateFlags.set(VALID_PC);
288        _pc = pc;
289    }
290
291    Request(int asid, Addr vaddr, int size, Flags flags, MasterID mid, Addr pc,
292            int cid, ThreadID tid)
293        : _taskId(ContextSwitchTaskId::Unknown)
294    {
295        setVirt(asid, vaddr, size, flags, mid, pc);
296        setThreadContext(cid, tid);
297    }
298
299    ~Request() {}
300
301    /**
302     * Set up CPU and thread numbers.
303     */
304    void
305    setThreadContext(int context_id, ThreadID tid)
306    {
307        _contextId = context_id;
308        _threadId = tid;
309        privateFlags.set(VALID_CONTEXT_ID|VALID_THREAD_ID);
310    }
311
312    /**
313     * Set up a physical (e.g. device) request in a previously
314     * allocated Request object.
315     */
316    void
317    setPhys(Addr paddr, int size, Flags flags, MasterID mid, Tick time)
318    {
319        assert(size >= 0);
320        _paddr = paddr;
321        _size = size;
322        _time = time;
323        _masterId = mid;
324        _flags.clear(~STICKY_FLAGS);
325        _flags.set(flags);
326        privateFlags.clear(~STICKY_PRIVATE_FLAGS);
327        privateFlags.set(VALID_PADDR|VALID_SIZE);
328        depth = 0;
329        accessDelta = 0;
330        //translateDelta = 0;
331    }
332
333    void
334    setPhys(Addr paddr, int size, Flags flags, MasterID mid)
335    {
336        setPhys(paddr, size, flags, mid, curTick());
337    }
338
339    /**
340     * Set up a virtual (e.g., CPU) request in a previously
341     * allocated Request object.
342     */
343    void
344    setVirt(int asid, Addr vaddr, int size, Flags flags, MasterID mid, Addr pc)
345    {
346        assert(size >= 0);
347        _asid = asid;
348        _vaddr = vaddr;
349        _size = size;
350        _masterId = mid;
351        _pc = pc;
352        _time = curTick();
353
354        _flags.clear(~STICKY_FLAGS);
355        _flags.set(flags);
356        privateFlags.clear(~STICKY_PRIVATE_FLAGS);
357        privateFlags.set(VALID_VADDR|VALID_SIZE|VALID_PC);
358        depth = 0;
359        accessDelta = 0;
360        translateDelta = 0;
361    }
362
363    /**
364     * Set just the physical address.  This usually used to record the
365     * result of a translation. However, when using virtualized CPUs
366     * setPhys() is sometimes called to finalize a physical address
367     * without a virtual address, so we can't check if the virtual
368     * address is valid.
369     */
370    void
371    setPaddr(Addr paddr)
372    {
373        _paddr = paddr;
374        privateFlags.set(VALID_PADDR);
375    }
376
377    /**
378     * Generate two requests as if this request had been split into two
379     * pieces. The original request can't have been translated already.
380     */
381    void splitOnVaddr(Addr split_addr, RequestPtr &req1, RequestPtr &req2)
382    {
383        assert(privateFlags.isSet(VALID_VADDR));
384        assert(privateFlags.noneSet(VALID_PADDR));
385        assert(split_addr > _vaddr && split_addr < _vaddr + _size);
386        req1 = new Request;
387        *req1 = *this;
388        req2 = new Request;
389        *req2 = *this;
390        req1->_size = split_addr - _vaddr;
391        req2->_vaddr = split_addr;
392        req2->_size = _size - req1->_size;
393    }
394
395    /**
396     * Accessor for paddr.
397     */
398    bool
399    hasPaddr()
400    {
401        return privateFlags.isSet(VALID_PADDR);
402    }
403
404    Addr
405    getPaddr()
406    {
407        assert(privateFlags.isSet(VALID_PADDR));
408        return _paddr;
409    }
410
411    /**
412     * Time for the TLB/table walker to successfully translate this request.
413     */
414    Tick translateDelta;
415
416    /**
417     * Access latency to complete this memory transaction not including
418     * translation time.
419     */
420    Tick accessDelta;
421
422    /**
423     * Level of the cache hierachy where this request was responded to
424     * (e.g. 0 = L1; 1 = L2).
425     */
426    int depth;
427
428    /**
429     *  Accessor for size.
430     */
431    bool
432    hasSize()
433    {
434        return privateFlags.isSet(VALID_SIZE);
435    }
436
437    int
438    getSize()
439    {
440        assert(privateFlags.isSet(VALID_SIZE));
441        return _size;
442    }
443
444    /** Accessor for time. */
445    Tick
446    time() const
447    {
448        assert(privateFlags.isSet(VALID_PADDR|VALID_VADDR));
449        return _time;
450    }
451
452    void
453    time(Tick time)
454    {
455        assert(privateFlags.isSet(VALID_PADDR|VALID_VADDR));
456        _time = time;
457    }
458
459    /** Accessor for flags. */
460    Flags
461    getFlags()
462    {
463        assert(privateFlags.isSet(VALID_PADDR|VALID_VADDR));
464        return _flags;
465    }
466
467    /** Note that unlike other accessors, this function sets *specific
468       flags* (ORs them in); it does not assign its argument to the
469       _flags field.  Thus this method should rightly be called
470       setFlags() and not just flags(). */
471    void
472    setFlags(Flags flags)
473    {
474        assert(privateFlags.isSet(VALID_PADDR|VALID_VADDR));
475        _flags.set(flags);
476    }
477
478    void
479    setArchFlags(Flags flags)
480    {
481        assert(privateFlags.isSet(VALID_PADDR|VALID_VADDR));
482        _flags.set(flags & ARCH_BITS);
483    }
484
485    /** Accessor function for vaddr.*/
486    Addr
487    getVaddr()
488    {
489        assert(privateFlags.isSet(VALID_VADDR));
490        return _vaddr;
491    }
492
493    /** Accesssor for the requestor id. */
494    MasterID
495    masterId()
496    {
497        return _masterId;
498    }
499
500    uint32_t
501    taskId() const
502    {
503        return _taskId;
504    }
505
506    void
507    taskId(uint32_t id) {
508        _taskId = id;
509    }
510
511    /** Accessor function for asid.*/
512    int
513    getAsid()
514    {
515        assert(privateFlags.isSet(VALID_VADDR));
516        return _asid;
517    }
518
519    /** Accessor function for asid.*/
520    void
521    setAsid(int asid)
522    {
523        _asid = asid;
524    }
525
526    /** Accessor function for architecture-specific flags.*/
527    ArchFlagsType
528    getArchFlags()
529    {
530        assert(privateFlags.isSet(VALID_PADDR|VALID_VADDR));
531        return _flags & ARCH_BITS;
532    }
533
534    /** Accessor function to check if sc result is valid. */
535    bool
536    extraDataValid()
537    {
538        return privateFlags.isSet(VALID_EXTRA_DATA);
539    }
540
541    /** Accessor function for store conditional return value.*/
542    uint64_t
543    getExtraData() const
544    {
545        assert(privateFlags.isSet(VALID_EXTRA_DATA));
546        return _extraData;
547    }
548
549    /** Accessor function for store conditional return value.*/
550    void
551    setExtraData(uint64_t extraData)
552    {
553        _extraData = extraData;
554        privateFlags.set(VALID_EXTRA_DATA);
555    }
556
557    bool
558    hasContextId() const
559    {
560        return privateFlags.isSet(VALID_CONTEXT_ID);
561    }
562
563    /** Accessor function for context ID.*/
564    int
565    contextId() const
566    {
567        assert(privateFlags.isSet(VALID_CONTEXT_ID));
568        return _contextId;
569    }
570
571    /** Accessor function for thread ID. */
572    int
573    threadId() const
574    {
575        assert(privateFlags.isSet(VALID_THREAD_ID));
576        return _threadId;
577    }
578
579    void
580    setPC(Addr pc)
581    {
582        privateFlags.set(VALID_PC);
583        _pc = pc;
584    }
585
586    bool
587    hasPC() const
588    {
589        return privateFlags.isSet(VALID_PC);
590    }
591
592    /** Accessor function for pc.*/
593    Addr
594    getPC() const
595    {
596        assert(privateFlags.isSet(VALID_PC));
597        return _pc;
598    }
599
600    /**
601     * Increment/Get the depth at which this request is responded to.
602     * This currently happens when the request misses in any cache level.
603     */
604    void incAccessDepth() { depth++; }
605    int getAccessDepth() const { return depth; }
606
607    /**
608     * Set/Get the time taken for this request to be successfully translated.
609     */
610    void setTranslateLatency() { translateDelta = curTick() - _time; }
611    Tick getTranslateLatency() const { return translateDelta; }
612
613    /**
614     * Set/Get the time taken to complete this request's access, not including
615     *  the time to successfully translate the request.
616     */
617    void setAccessLatency() { accessDelta = curTick() - _time - translateDelta; }
618    Tick getAccessLatency() const { return accessDelta; }
619
620    /** Accessor functions for flags.  Note that these are for testing
621       only; setting flags should be done via setFlags(). */
622    bool isUncacheable() const { return _flags.isSet(UNCACHEABLE); }
623    bool isInstFetch() const { return _flags.isSet(INST_FETCH); }
624    bool isPrefetch() const { return _flags.isSet(PREFETCH); }
625    bool isLLSC() const { return _flags.isSet(LLSC); }
626    bool isPriv() const { return _flags.isSet(PRIVILEGED); }
627    bool isLocked() const { return _flags.isSet(LOCKED); }
628    bool isSwap() const { return _flags.isSet(MEM_SWAP|MEM_SWAP_COND); }
629    bool isCondSwap() const { return _flags.isSet(MEM_SWAP_COND); }
630    bool isMmappedIpr() const { return _flags.isSet(MMAPPED_IPR); }
631    bool isClearLL() const { return _flags.isSet(CLEAR_LL); }
632    bool isSecure() const { return _flags.isSet(SECURE); }
633    bool isPTWalk() const { return _flags.isSet(PT_WALK); }
634};
635
636#endif // __MEM_REQUEST_HH__
637