request.hh revision 9911:676d3dcf1cc2 
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    /** The request should be handled by the generic IPR code (only
131     * valid together with MMAPPED_IPR) */
132    static const FlagsType GENERIC_IPR                 = 0x08000000;
133
134    /** These flags are *not* cleared when a Request object is reused
135       (assigned a new address). */
136    static const FlagsType STICKY_FLAGS = INST_FETCH;
137
138    /** Request Ids that are statically allocated
139     * @{*/
140    /** This request id is used for writeback requests by the caches */
141    static const MasterID wbMasterId = 0;
142    /** This request id is used for functional requests that don't come from a
143     * particular device
144     */
145    static const MasterID funcMasterId = 1;
146    /** This request id is used for message signaled interrupts */
147    static const MasterID intMasterId = 2;
148    /** Invalid request id for assertion checking only. It is invalid behavior
149     * to ever send this id as part of a request.
150     * @todo C++1x replace with numeric_limits when constexpr is added  */
151    static const MasterID invldMasterId = USHRT_MAX;
152    /** @} */
153
154    /** Invalid or unknown Pid. Possible when operating system is not present
155     *  or has not assigned a pid yet */
156    static const uint32_t invldPid = UINT_MAX;
157
158  private:
159    typedef uint8_t PrivateFlagsType;
160    typedef ::Flags<PrivateFlagsType> PrivateFlags;
161
162    /** Whether or not the size is valid. */
163    static const PrivateFlagsType VALID_SIZE           = 0x00000001;
164    /** Whether or not paddr is valid (has been written yet). */
165    static const PrivateFlagsType VALID_PADDR          = 0x00000002;
166    /** Whether or not the vaddr & asid are valid. */
167    static const PrivateFlagsType VALID_VADDR          = 0x00000004;
168    /** Whether or not the pc is valid. */
169    static const PrivateFlagsType VALID_PC             = 0x00000010;
170    /** Whether or not the context ID is valid. */
171    static const PrivateFlagsType VALID_CONTEXT_ID     = 0x00000020;
172    static const PrivateFlagsType VALID_THREAD_ID      = 0x00000040;
173    /** Whether or not the sc result is valid. */
174    static const PrivateFlagsType VALID_EXTRA_DATA     = 0x00000080;
175
176    /** These flags are *not* cleared when a Request object is reused
177       (assigned a new address). */
178    static const PrivateFlagsType STICKY_PRIVATE_FLAGS =
179        VALID_CONTEXT_ID | VALID_THREAD_ID;
180
181  private:
182    /**
183     * The physical address of the request. Valid only if validPaddr
184     * is set.
185     */
186    Addr _paddr;
187
188    /**
189     * The size of the request. This field must be set when vaddr or
190     * paddr is written via setVirt() or setPhys(), so it is always
191     * valid as long as one of the address fields is valid.
192     */
193    int _size;
194
195    /** The requestor ID which is unique in the system for all ports
196     * that are capable of issuing a transaction
197     */
198    MasterID _masterId;
199
200    /** Flag structure for the request. */
201    Flags _flags;
202
203    /** Private flags for field validity checking. */
204    PrivateFlags privateFlags;
205
206    /**
207     * The time this request was started. Used to calculate
208     * latencies. This field is set to curTick() any time paddr or vaddr
209     * is written.
210     */
211    Tick _time;
212
213    /** The address space ID. */
214    int _asid;
215
216    /** The virtual address of the request. */
217    Addr _vaddr;
218
219    /**
220     * Extra data for the request, such as the return value of
221     * store conditional or the compare value for a CAS. */
222    uint64_t _extraData;
223
224    /** The context ID (for statistics, typically). */
225    int _contextId;
226    /** The thread ID (id within this CPU) */
227    int _threadId;
228
229    /** program counter of initiating access; for tracing/debugging */
230    Addr _pc;
231
232  public:
233    /** Minimal constructor.  No fields are initialized.
234     *  (Note that _flags and privateFlags are cleared by Flags
235     *  default constructor.)
236     */
237    Request()
238    {}
239
240    /**
241     * Constructor for physical (e.g. device) requests.  Initializes
242     * just physical address, size, flags, and timestamp (to curTick()).
243     * These fields are adequate to perform a request.
244     */
245    Request(Addr paddr, int size, Flags flags, MasterID mid)
246    {
247        setPhys(paddr, size, flags, mid);
248    }
249
250    Request(Addr paddr, int size, Flags flags, MasterID mid, Tick time)
251    {
252        setPhys(paddr, size, flags, mid, time);
253    }
254
255    Request(Addr paddr, int size, Flags flags, MasterID mid, Tick time, Addr pc)
256    {
257        setPhys(paddr, size, flags, mid, time);
258        privateFlags.set(VALID_PC);
259        _pc = pc;
260    }
261
262    Request(int asid, Addr vaddr, int size, Flags flags, MasterID mid, Addr pc,
263            int cid, ThreadID tid)
264    {
265        setVirt(asid, vaddr, size, flags, mid, pc);
266        setThreadContext(cid, tid);
267    }
268
269    ~Request() {}
270
271    /**
272     * Set up CPU and thread numbers.
273     */
274    void
275    setThreadContext(int context_id, ThreadID tid)
276    {
277        _contextId = context_id;
278        _threadId = tid;
279        privateFlags.set(VALID_CONTEXT_ID|VALID_THREAD_ID);
280    }
281
282    /**
283     * Set up a physical (e.g. device) request in a previously
284     * allocated Request object.
285     */
286    void
287    setPhys(Addr paddr, int size, Flags flags, MasterID mid, Tick time)
288    {
289        assert(size >= 0);
290        _paddr = paddr;
291        _size = size;
292        _time = time;
293        _masterId = mid;
294        _flags.clear(~STICKY_FLAGS);
295        _flags.set(flags);
296        privateFlags.clear(~STICKY_PRIVATE_FLAGS);
297        privateFlags.set(VALID_PADDR|VALID_SIZE);
298    }
299
300    void
301    setPhys(Addr paddr, int size, Flags flags, MasterID mid)
302    {
303        setPhys(paddr, size, flags, mid, curTick());
304    }
305
306    /**
307     * Set up a virtual (e.g., CPU) request in a previously
308     * allocated Request object.
309     */
310    void
311    setVirt(int asid, Addr vaddr, int size, Flags flags, MasterID mid, Addr pc)
312    {
313        assert(size >= 0);
314        _asid = asid;
315        _vaddr = vaddr;
316        _size = size;
317        _masterId = mid;
318        _pc = pc;
319        _time = curTick();
320
321        _flags.clear(~STICKY_FLAGS);
322        _flags.set(flags);
323        privateFlags.clear(~STICKY_PRIVATE_FLAGS);
324        privateFlags.set(VALID_VADDR|VALID_SIZE|VALID_PC);
325    }
326
327    /**
328     * Set just the physical address.  This usually used to record the
329     * result of a translation. However, when using virtualized CPUs
330     * setPhys() is sometimes called to finalize a physical address
331     * without a virtual address, so we can't check if the virtual
332     * address is valid.
333     */
334    void
335    setPaddr(Addr paddr)
336    {
337        _paddr = paddr;
338        privateFlags.set(VALID_PADDR);
339    }
340
341    /**
342     * Generate two requests as if this request had been split into two
343     * pieces. The original request can't have been translated already.
344     */
345    void splitOnVaddr(Addr split_addr, RequestPtr &req1, RequestPtr &req2)
346    {
347        assert(privateFlags.isSet(VALID_VADDR));
348        assert(privateFlags.noneSet(VALID_PADDR));
349        assert(split_addr > _vaddr && split_addr < _vaddr + _size);
350        req1 = new Request;
351        *req1 = *this;
352        req2 = new Request;
353        *req2 = *this;
354        req1->_size = split_addr - _vaddr;
355        req2->_vaddr = split_addr;
356        req2->_size = _size - req1->_size;
357    }
358
359    /**
360     * Accessor for paddr.
361     */
362    bool
363    hasPaddr()
364    {
365        return privateFlags.isSet(VALID_PADDR);
366    }
367
368    Addr
369    getPaddr()
370    {
371        assert(privateFlags.isSet(VALID_PADDR));
372        return _paddr;
373    }
374
375    /**
376     *  Accessor for size.
377     */
378    bool
379    hasSize()
380    {
381        return privateFlags.isSet(VALID_SIZE);
382    }
383
384    int
385    getSize()
386    {
387        assert(privateFlags.isSet(VALID_SIZE));
388        return _size;
389    }
390
391    /** Accessor for time. */
392    Tick
393    time() const
394    {
395        assert(privateFlags.isSet(VALID_PADDR|VALID_VADDR));
396        return _time;
397    }
398
399    void
400    time(Tick time)
401    {
402        assert(privateFlags.isSet(VALID_PADDR|VALID_VADDR));
403        _time = time;
404    }
405
406    /** Accessor for flags. */
407    Flags
408    getFlags()
409    {
410        assert(privateFlags.isSet(VALID_PADDR|VALID_VADDR));
411        return _flags;
412    }
413
414    /** Note that unlike other accessors, this function sets *specific
415       flags* (ORs them in); it does not assign its argument to the
416       _flags field.  Thus this method should rightly be called
417       setFlags() and not just flags(). */
418    void
419    setFlags(Flags flags)
420    {
421        assert(privateFlags.isSet(VALID_PADDR|VALID_VADDR));
422        _flags.set(flags);
423    }
424
425    /** Accessor function for vaddr.*/
426    Addr
427    getVaddr()
428    {
429        assert(privateFlags.isSet(VALID_VADDR));
430        return _vaddr;
431    }
432
433    /** Accesssor for the requestor id. */
434    MasterID
435    masterId()
436    {
437        return _masterId;
438    }
439
440    /** Accessor function for asid.*/
441    int
442    getAsid()
443    {
444        assert(privateFlags.isSet(VALID_VADDR));
445        return _asid;
446    }
447
448    /** Accessor function for asid.*/
449    void
450    setAsid(int asid)
451    {
452        _asid = asid;
453    }
454
455    /** Accessor function for asi.*/
456    uint8_t
457    getAsi()
458    {
459        assert(privateFlags.isSet(VALID_VADDR));
460        return _flags & ASI_BITS;
461    }
462
463    /** Accessor function to check if sc result is valid. */
464    bool
465    extraDataValid()
466    {
467        return privateFlags.isSet(VALID_EXTRA_DATA);
468    }
469
470    /** Accessor function for store conditional return value.*/
471    uint64_t
472    getExtraData() const
473    {
474        assert(privateFlags.isSet(VALID_EXTRA_DATA));
475        return _extraData;
476    }
477
478    /** Accessor function for store conditional return value.*/
479    void
480    setExtraData(uint64_t extraData)
481    {
482        _extraData = extraData;
483        privateFlags.set(VALID_EXTRA_DATA);
484    }
485
486    bool
487    hasContextId() const
488    {
489        return privateFlags.isSet(VALID_CONTEXT_ID);
490    }
491
492    /** Accessor function for context ID.*/
493    int
494    contextId() const
495    {
496        assert(privateFlags.isSet(VALID_CONTEXT_ID));
497        return _contextId;
498    }
499
500    /** Accessor function for thread ID. */
501    int
502    threadId() const
503    {
504        assert(privateFlags.isSet(VALID_THREAD_ID));
505        return _threadId;
506    }
507
508    bool
509    hasPC() const
510    {
511        return privateFlags.isSet(VALID_PC);
512    }
513
514    /** Accessor function for pc.*/
515    Addr
516    getPC() const
517    {
518        assert(privateFlags.isSet(VALID_PC));
519        return _pc;
520    }
521
522    /** Accessor functions for flags.  Note that these are for testing
523       only; setting flags should be done via setFlags(). */
524    bool isUncacheable() const { return _flags.isSet(UNCACHEABLE); }
525    bool isInstFetch() const { return _flags.isSet(INST_FETCH); }
526    bool isPrefetch() const { return _flags.isSet(PREFETCH); }
527    bool isLLSC() const { return _flags.isSet(LLSC); }
528    bool isLocked() const { return _flags.isSet(LOCKED); }
529    bool isSwap() const { return _flags.isSet(MEM_SWAP|MEM_SWAP_COND); }
530    bool isCondSwap() const { return _flags.isSet(MEM_SWAP_COND); }
531    bool isMmappedIpr() const { return _flags.isSet(MMAPPED_IPR); }
532    bool isClearLL() const { return _flags.isSet(CLEAR_LL); }
533};
534
535#endif // __MEM_REQUEST_HH__
536