request.hh revision 9760:9db8a438608c 
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 ::Flags<FlagsType> Flags;
90
91    /** ASI information for this request if it exists. */
92    static const FlagsType ASI_BITS                    = 0x000000FF;
93    /** The request was an instruction fetch. */
94    static const FlagsType INST_FETCH                  = 0x00000100;
95    /** The virtual address is also the physical address. */
96    static const FlagsType PHYSICAL                    = 0x00000200;
97    /** The request is an ALPHA VPTE pal access (hw_ld). */
98    static const FlagsType VPTE                        = 0x00000400;
99    /** Use the alternate mode bits in ALPHA. */
100    static const FlagsType ALTMODE                     = 0x00000800;
101    /** The request is to an uncacheable address. */
102    static const FlagsType UNCACHEABLE                 = 0x00001000;
103    /** This request is to a memory mapped register. */
104    static const FlagsType MMAPPED_IPR                  = 0x00002000;
105    /** This request is a clear exclusive. */
106    static const FlagsType CLEAR_LL                    = 0x00004000;
107
108    /** The request should not cause a memory access. */
109    static const FlagsType NO_ACCESS                   = 0x00080000;
110    /** This request will lock or unlock the accessed memory. When used with
111     * a load, the access locks the particular chunk of memory. When used
112     * with a store, it unlocks. The rule is that locked accesses have to be
113     * made up of a locked load, some operation on the data, and then a locked
114     * store.
115     */
116    static const FlagsType LOCKED                      = 0x00100000;
117    /** The request is a Load locked/store conditional. */
118    static const FlagsType LLSC                        = 0x00200000;
119    /** This request is for a memory swap. */
120    static const FlagsType MEM_SWAP                    = 0x00400000;
121    static const FlagsType MEM_SWAP_COND               = 0x00800000;
122
123    /** The request is a prefetch. */
124    static const FlagsType PREFETCH                    = 0x01000000;
125    /** The request should be prefetched into the exclusive state. */
126    static const FlagsType PF_EXCLUSIVE                = 0x02000000;
127    /** The request should be marked as LRU. */
128    static const FlagsType EVICT_NEXT                  = 0x04000000;
129
130    /** These flags are *not* cleared when a Request object is reused
131       (assigned a new address). */
132    static const FlagsType STICKY_FLAGS = INST_FETCH;
133
134    /** Request Ids that are statically allocated
135     * @{*/
136    /** This request id is used for writeback requests by the caches */
137    static const MasterID wbMasterId = 0;
138    /** This request id is used for functional requests that don't come from a
139     * particular device
140     */
141    static const MasterID funcMasterId = 1;
142    /** This request id is used for message signaled interrupts */
143    static const MasterID intMasterId = 2;
144    /** Invalid request id for assertion checking only. It is invalid behavior
145     * to ever send this id as part of a request.
146     * @todo C++1x replace with numeric_limits when constexpr is added  */
147    static const MasterID invldMasterId = USHRT_MAX;
148    /** @} */
149
150    /** Invalid or unknown Pid. Possible when operating system is not present
151     *  or has not assigned a pid yet */
152    static const uint32_t invldPid = UINT_MAX;
153
154  private:
155    typedef uint8_t PrivateFlagsType;
156    typedef ::Flags<PrivateFlagsType> PrivateFlags;
157
158    /** Whether or not the size is valid. */
159    static const PrivateFlagsType VALID_SIZE           = 0x00000001;
160    /** Whether or not paddr is valid (has been written yet). */
161    static const PrivateFlagsType VALID_PADDR          = 0x00000002;
162    /** Whether or not the vaddr & asid are valid. */
163    static const PrivateFlagsType VALID_VADDR          = 0x00000004;
164    /** Whether or not the pc is valid. */
165    static const PrivateFlagsType VALID_PC             = 0x00000010;
166    /** Whether or not the context ID is valid. */
167    static const PrivateFlagsType VALID_CONTEXT_ID     = 0x00000020;
168    static const PrivateFlagsType VALID_THREAD_ID      = 0x00000040;
169    /** Whether or not the sc result is valid. */
170    static const PrivateFlagsType VALID_EXTRA_DATA     = 0x00000080;
171
172    /** These flags are *not* cleared when a Request object is reused
173       (assigned a new address). */
174    static const PrivateFlagsType STICKY_PRIVATE_FLAGS =
175        VALID_CONTEXT_ID | VALID_THREAD_ID;
176
177  private:
178    /**
179     * The physical address of the request. Valid only if validPaddr
180     * is set.
181     */
182    Addr _paddr;
183
184    /**
185     * The size of the request. This field must be set when vaddr or
186     * paddr is written via setVirt() or setPhys(), so it is always
187     * valid as long as one of the address fields is valid.
188     */
189    int _size;
190
191    /** The requestor ID which is unique in the system for all ports
192     * that are capable of issuing a transaction
193     */
194    MasterID _masterId;
195
196    /** Flag structure for the request. */
197    Flags _flags;
198
199    /** Private flags for field validity checking. */
200    PrivateFlags privateFlags;
201
202    /**
203     * The time this request was started. Used to calculate
204     * latencies. This field is set to curTick() any time paddr or vaddr
205     * is written.
206     */
207    Tick _time;
208
209    /** The address space ID. */
210    int _asid;
211
212    /** The virtual address of the request. */
213    Addr _vaddr;
214
215    /**
216     * Extra data for the request, such as the return value of
217     * store conditional or the compare value for a CAS. */
218    uint64_t _extraData;
219
220    /** The context ID (for statistics, typically). */
221    int _contextId;
222    /** The thread ID (id within this CPU) */
223    int _threadId;
224
225    /** program counter of initiating access; for tracing/debugging */
226    Addr _pc;
227
228  public:
229    /** Minimal constructor.  No fields are initialized.
230     *  (Note that _flags and privateFlags are cleared by Flags
231     *  default constructor.)
232     */
233    Request()
234    {}
235
236    /**
237     * Constructor for physical (e.g. device) requests.  Initializes
238     * just physical address, size, flags, and timestamp (to curTick()).
239     * These fields are adequate to perform a request.
240     */
241    Request(Addr paddr, int size, Flags flags, MasterID mid)
242    {
243        setPhys(paddr, size, flags, mid);
244    }
245
246    Request(Addr paddr, int size, Flags flags, MasterID mid, Tick time)
247    {
248        setPhys(paddr, size, flags, mid, time);
249    }
250
251    Request(Addr paddr, int size, Flags flags, MasterID mid, Tick time, Addr pc)
252    {
253        setPhys(paddr, size, flags, mid, time);
254        privateFlags.set(VALID_PC);
255        _pc = pc;
256    }
257
258    Request(int asid, Addr vaddr, int size, Flags flags, MasterID mid, Addr pc,
259            int cid, ThreadID tid)
260    {
261        setVirt(asid, vaddr, size, flags, mid, pc);
262        setThreadContext(cid, tid);
263    }
264
265    ~Request() {}
266
267    /**
268     * Set up CPU and thread numbers.
269     */
270    void
271    setThreadContext(int context_id, ThreadID tid)
272    {
273        _contextId = context_id;
274        _threadId = tid;
275        privateFlags.set(VALID_CONTEXT_ID|VALID_THREAD_ID);
276    }
277
278    /**
279     * Set up a physical (e.g. device) request in a previously
280     * allocated Request object.
281     */
282    void
283    setPhys(Addr paddr, int size, Flags flags, MasterID mid, Tick time)
284    {
285        assert(size >= 0);
286        _paddr = paddr;
287        _size = size;
288        _time = time;
289        _masterId = mid;
290        _flags.clear(~STICKY_FLAGS);
291        _flags.set(flags);
292        privateFlags.clear(~STICKY_PRIVATE_FLAGS);
293        privateFlags.set(VALID_PADDR|VALID_SIZE);
294    }
295
296    void
297    setPhys(Addr paddr, int size, Flags flags, MasterID mid)
298    {
299        setPhys(paddr, size, flags, mid, curTick());
300    }
301
302    /**
303     * Set up a virtual (e.g., CPU) request in a previously
304     * allocated Request object.
305     */
306    void
307    setVirt(int asid, Addr vaddr, int size, Flags flags, MasterID mid, Addr pc)
308    {
309        assert(size >= 0);
310        _asid = asid;
311        _vaddr = vaddr;
312        _size = size;
313        _masterId = mid;
314        _pc = pc;
315        _time = curTick();
316
317        _flags.clear(~STICKY_FLAGS);
318        _flags.set(flags);
319        privateFlags.clear(~STICKY_PRIVATE_FLAGS);
320        privateFlags.set(VALID_VADDR|VALID_SIZE|VALID_PC);
321    }
322
323    /**
324     * Set just the physical address.  This usually used to record the
325     * result of a translation. However, when using virtualized CPUs
326     * setPhys() is sometimes called to finalize a physical address
327     * without a virtual address, so we can't check if the virtual
328     * address is valid.
329     */
330    void
331    setPaddr(Addr paddr)
332    {
333        _paddr = paddr;
334        privateFlags.set(VALID_PADDR);
335    }
336
337    /**
338     * Generate two requests as if this request had been split into two
339     * pieces. The original request can't have been translated already.
340     */
341    void splitOnVaddr(Addr split_addr, RequestPtr &req1, RequestPtr &req2)
342    {
343        assert(privateFlags.isSet(VALID_VADDR));
344        assert(privateFlags.noneSet(VALID_PADDR));
345        assert(split_addr > _vaddr && split_addr < _vaddr + _size);
346        req1 = new Request;
347        *req1 = *this;
348        req2 = new Request;
349        *req2 = *this;
350        req1->_size = split_addr - _vaddr;
351        req2->_vaddr = split_addr;
352        req2->_size = _size - req1->_size;
353    }
354
355    /**
356     * Accessor for paddr.
357     */
358    bool
359    hasPaddr()
360    {
361        return privateFlags.isSet(VALID_PADDR);
362    }
363
364    Addr
365    getPaddr()
366    {
367        assert(privateFlags.isSet(VALID_PADDR));
368        return _paddr;
369    }
370
371    /**
372     *  Accessor for size.
373     */
374    bool
375    hasSize()
376    {
377        return privateFlags.isSet(VALID_SIZE);
378    }
379
380    int
381    getSize()
382    {
383        assert(privateFlags.isSet(VALID_SIZE));
384        return _size;
385    }
386
387    /** Accessor for time. */
388    Tick
389    time() const
390    {
391        assert(privateFlags.isSet(VALID_PADDR|VALID_VADDR));
392        return _time;
393    }
394
395    void
396    time(Tick time)
397    {
398        assert(privateFlags.isSet(VALID_PADDR|VALID_VADDR));
399        _time = time;
400    }
401
402    /** Accessor for flags. */
403    Flags
404    getFlags()
405    {
406        assert(privateFlags.isSet(VALID_PADDR|VALID_VADDR));
407        return _flags;
408    }
409
410    /** Note that unlike other accessors, this function sets *specific
411       flags* (ORs them in); it does not assign its argument to the
412       _flags field.  Thus this method should rightly be called
413       setFlags() and not just flags(). */
414    void
415    setFlags(Flags flags)
416    {
417        assert(privateFlags.isSet(VALID_PADDR|VALID_VADDR));
418        _flags.set(flags);
419    }
420
421    /** Accessor function for vaddr.*/
422    Addr
423    getVaddr()
424    {
425        assert(privateFlags.isSet(VALID_VADDR));
426        return _vaddr;
427    }
428
429    /** Accesssor for the requestor id. */
430    MasterID
431    masterId()
432    {
433        return _masterId;
434    }
435
436    /** Accessor function for asid.*/
437    int
438    getAsid()
439    {
440        assert(privateFlags.isSet(VALID_VADDR));
441        return _asid;
442    }
443
444    /** Accessor function for asid.*/
445    void
446    setAsid(int asid)
447    {
448        _asid = asid;
449    }
450
451    /** Accessor function for asi.*/
452    uint8_t
453    getAsi()
454    {
455        assert(privateFlags.isSet(VALID_VADDR));
456        return _flags & ASI_BITS;
457    }
458
459    /** Accessor function to check if sc result is valid. */
460    bool
461    extraDataValid()
462    {
463        return privateFlags.isSet(VALID_EXTRA_DATA);
464    }
465
466    /** Accessor function for store conditional return value.*/
467    uint64_t
468    getExtraData() const
469    {
470        assert(privateFlags.isSet(VALID_EXTRA_DATA));
471        return _extraData;
472    }
473
474    /** Accessor function for store conditional return value.*/
475    void
476    setExtraData(uint64_t extraData)
477    {
478        _extraData = extraData;
479        privateFlags.set(VALID_EXTRA_DATA);
480    }
481
482    bool
483    hasContextId() const
484    {
485        return privateFlags.isSet(VALID_CONTEXT_ID);
486    }
487
488    /** Accessor function for context ID.*/
489    int
490    contextId() const
491    {
492        assert(privateFlags.isSet(VALID_CONTEXT_ID));
493        return _contextId;
494    }
495
496    /** Accessor function for thread ID. */
497    int
498    threadId() const
499    {
500        assert(privateFlags.isSet(VALID_THREAD_ID));
501        return _threadId;
502    }
503
504    bool
505    hasPC() const
506    {
507        return privateFlags.isSet(VALID_PC);
508    }
509
510    /** Accessor function for pc.*/
511    Addr
512    getPC() const
513    {
514        assert(privateFlags.isSet(VALID_PC));
515        return _pc;
516    }
517
518    /** Accessor functions for flags.  Note that these are for testing
519       only; setting flags should be done via setFlags(). */
520    bool isUncacheable() const { return _flags.isSet(UNCACHEABLE); }
521    bool isInstFetch() const { return _flags.isSet(INST_FETCH); }
522    bool isPrefetch() const { return _flags.isSet(PREFETCH); }
523    bool isLLSC() const { return _flags.isSet(LLSC); }
524    bool isLocked() const { return _flags.isSet(LOCKED); }
525    bool isSwap() const { return _flags.isSet(MEM_SWAP|MEM_SWAP_COND); }
526    bool isCondSwap() const { return _flags.isSet(MEM_SWAP_COND); }
527    bool isMmappedIpr() const { return _flags.isSet(MMAPPED_IPR); }
528    bool isClearLL() const { return _flags.isSet(CLEAR_LL); }
529};
530
531#endif // __MEM_REQUEST_HH__
532