1/*
2 * Copyright (c) 2002-2005 The Regents of The University of Michigan
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions are
7 * met: redistributions of source code must retain the above copyright
8 * notice, this list of conditions and the following disclaimer;
9 * redistributions in binary form must reproduce the above copyright
10 * notice, this list of conditions and the following disclaimer in the
11 * documentation and/or other materials provided with the distribution;
12 * neither the name of the copyright holders nor the names of its
13 * contributors may be used to endorse or promote products derived from
14 * this software without specific prior written permission.
15 *
16 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
17 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
18 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
19 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
20 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
21 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
22 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
23 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
24 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
25 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
26 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27 *
28 * Authors: Ron Dreslinski
29 * Steve Reinhardt
30 * Ali Saidi
31 */
32
33/**
34 * @file
35 * Declaration of a request, the overall memory request consisting of
36 the parts of the request that are persistent throughout the transaction.
37 */
38
39#ifndef __MEM_REQUEST_HH__
40#define __MEM_REQUEST_HH__
41
42#include <cassert>
43
44#include "base/fast_alloc.hh"
45#include "base/flags.hh"
46#include "base/misc.hh"
47#include "base/types.hh"
48#include "sim/core.hh"
49
50class Request;
51
52typedef Request* RequestPtr;
53
54class Request : public FastAlloc
55{
56 public:
57 typedef uint32_t FlagsType;
58 typedef ::Flags<FlagsType> Flags;
59
60 /** ASI information for this request if it exists. */
61 static const FlagsType ASI_BITS = 0x000000FF;
62 /** The request was an instruction fetch. */
63 static const FlagsType INST_FETCH = 0x00000100;
64 /** The virtual address is also the physical address. */
65 static const FlagsType PHYSICAL = 0x00000200;
66 /** The request is an ALPHA VPTE pal access (hw_ld). */
67 static const FlagsType VPTE = 0x00000400;
68 /** Use the alternate mode bits in ALPHA. */
69 static const FlagsType ALTMODE = 0x00000800;
70 /** The request is to an uncacheable address. */
71 static const FlagsType UNCACHEABLE = 0x00001000;
72 /** This request is to a memory mapped register. */
73 static const FlagsType MMAPED_IPR = 0x00002000;
74
75 /** The request should not cause a page fault. */
76 static const FlagsType NO_FAULT = 0x00010000;
77 /** The request should ignore unaligned access faults */
78 static const FlagsType NO_ALIGN_FAULT = 0x00020000;
79 /** The request should ignore unaligned access faults */
80 static const FlagsType NO_HALF_WORD_ALIGN_FAULT = 0x00040000;
81 /** The request should not cause a memory access. */
82 static const FlagsType NO_ACCESS = 0x00080000;
83 /** This request will lock or unlock the accessed memory. When used with
84 * a load, the access locks the particular chunk of memory. When used
85 * with a store, it unlocks. The rule is that locked accesses have to be
86 * made up of a locked load, some operation on the data, and then a locked
87 * store.
88 */
89 static const FlagsType LOCKED = 0x00100000;
90 /** The request is a Load locked/store conditional. */
91 static const FlagsType LLSC = 0x00200000;
92 /** This request is for a memory swap. */
93 static const FlagsType MEM_SWAP = 0x00400000;
94 static const FlagsType MEM_SWAP_COND = 0x00800000;
95
96 /** The request is a prefetch. */
97 static const FlagsType PREFETCH = 0x01000000;
98 /** The request should be prefetched into the exclusive state. */
99 static const FlagsType PF_EXCLUSIVE = 0x02000000;
100 /** The request should be marked as LRU. */
101 static const FlagsType EVICT_NEXT = 0x04000000;
102
103 /** These flags are *not* cleared when a Request object is reused
104 (assigned a new address). */
105 static const FlagsType STICKY_FLAGS = INST_FETCH;
106
107 private:
108 typedef uint8_t PrivateFlagsType;
109 typedef ::Flags<PrivateFlagsType> PrivateFlags;
110
111 /** Whether or not the size is valid. */
112 static const PrivateFlagsType VALID_SIZE = 0x00000001;
113 /** Whether or not paddr is valid (has been written yet). */
114 static const PrivateFlagsType VALID_PADDR = 0x00000002;
115 /** Whether or not the vaddr & asid are valid. */
116 static const PrivateFlagsType VALID_VADDR = 0x00000004;
117 /** Whether or not the pc is valid. */
118 static const PrivateFlagsType VALID_PC = 0x00000010;
119 /** Whether or not the context ID is valid. */
120 static const PrivateFlagsType VALID_CONTEXT_ID = 0x00000020;
121 static const PrivateFlagsType VALID_THREAD_ID = 0x00000040;
122 /** Whether or not the sc result is valid. */
123 static const PrivateFlagsType VALID_EXTRA_DATA = 0x00000080;
124
125 /** These flags are *not* cleared when a Request object is reused
126 (assigned a new address). */
127 static const PrivateFlagsType STICKY_PRIVATE_FLAGS =
128 VALID_CONTEXT_ID | VALID_THREAD_ID;
129
130 private:
131 /**
132 * The physical address of the request. Valid only if validPaddr
133 * is set.
134 */
135 Addr _paddr;
136
137 /**
138 * The size of the request. This field must be set when vaddr or
139 * paddr is written via setVirt() or setPhys(), so it is always
140 * valid as long as one of the address fields is valid.
141 */
142 int _size;
143
144 /** Flag structure for the request. */
145 Flags _flags;
146
147 /** Private flags for field validity checking. */
148 PrivateFlags privateFlags;
149
150 /**
151 * The time this request was started. Used to calculate
152 * latencies. This field is set to curTick any time paddr or vaddr
153 * is written.
154 */
155 Tick _time;
156
157 /** The address space ID. */
158 int _asid;
159
160 /** The virtual address of the request. */
161 Addr _vaddr;
162
163 /**
164 * Extra data for the request, such as the return value of
165 * store conditional or the compare value for a CAS. */
166 uint64_t _extraData;
167
168 /** The context ID (for statistics, typically). */
169 int _contextId;
170 /** The thread ID (id within this CPU) */
171 int _threadId;
172
173 /** program counter of initiating access; for tracing/debugging */
174 Addr _pc;
175
176 public:
177 /** Minimal constructor. No fields are initialized.
178 * (Note that _flags and privateFlags are cleared by Flags
179 * default constructor.)
180 */
181 Request()
182 {}
183
184 /**
185 * Constructor for physical (e.g. device) requests. Initializes
186 * just physical address, size, flags, and timestamp (to curTick).
187 * These fields are adequate to perform a request.
188 */
189 Request(Addr paddr, int size, Flags flags)
190 {
191 setPhys(paddr, size, flags);
192 }
193
194 Request(Addr paddr, int size, Flags flags, Tick time)
195 {
196 setPhys(paddr, size, flags, time);
197 }
198
199 Request(int asid, Addr vaddr, int size, Flags flags, Addr pc,
200 int cid, ThreadID tid)
201 {
202 setVirt(asid, vaddr, size, flags, pc);
203 setThreadContext(cid, tid);
204 }
205
206 ~Request() {} // for FastAlloc
207
208 /**
209 * Set up CPU and thread numbers.
210 */
211 void
212 setThreadContext(int context_id, ThreadID tid)
213 {
214 _contextId = context_id;
215 _threadId = tid;
216 privateFlags.set(VALID_CONTEXT_ID|VALID_THREAD_ID);
217 }
218
219 /**
220 * Set up a physical (e.g. device) request in a previously
221 * allocated Request object.
222 */
223 void
224 setPhys(Addr paddr, int size, Flags flags, Tick time)
225 {
226 assert(size >= 0);
227 _paddr = paddr;
228 _size = size;
229 _time = time;
230
231 _flags.clear(~STICKY_FLAGS);
232 _flags.set(flags);
233 privateFlags.clear(~STICKY_PRIVATE_FLAGS);
234 privateFlags.set(VALID_PADDR|VALID_SIZE);
235 }
236
237 void
238 setPhys(Addr paddr, int size, Flags flags)
239 {
240 setPhys(paddr, size, flags, curTick);
241 }
242
243 /**
244 * Set up a virtual (e.g., CPU) request in a previously
245 * allocated Request object.
246 */
247 void
248 setVirt(int asid, Addr vaddr, int size, Flags flags, Addr pc)
249 {
250 assert(size >= 0);
251 _asid = asid;
252 _vaddr = vaddr;
253 _size = size;
254 _pc = pc;
255 _time = curTick;
256
257 _flags.clear(~STICKY_FLAGS);
258 _flags.set(flags);
259 privateFlags.clear(~STICKY_PRIVATE_FLAGS);
260 privateFlags.set(VALID_VADDR|VALID_SIZE|VALID_PC);
261 }
262
263 /**
264 * Set just the physical address. This should only be used to
265 * record the result of a translation, and thus the vaddr must be
266 * valid before this method is called. Otherwise, use setPhys()
267 * to guarantee that the size and flags are also set.
268 */
269 void
270 setPaddr(Addr paddr)
271 {
272 assert(privateFlags.isSet(VALID_VADDR));
273 _paddr = paddr;
274 privateFlags.set(VALID_PADDR);
275 }
276
277 /**
278 * Generate two requests as if this request had been split into two
279 * pieces. The original request can't have been translated already.
280 */
281 void splitOnVaddr(Addr split_addr, RequestPtr &req1, RequestPtr &req2)
282 {
283 assert(privateFlags.isSet(VALID_VADDR));
284 assert(privateFlags.noneSet(VALID_PADDR));
285 assert(split_addr > _vaddr && split_addr < _vaddr + _size);
286 req1 = new Request;
287 *req1 = *this;
288 req2 = new Request;
289 *req2 = *this;
290 req1->_size = split_addr - _vaddr;
291 req2->_vaddr = split_addr;
292 req2->_size = _size - req1->_size;
293 }
294
295 /**
296 * Accessor for paddr.
297 */
298 bool
299 hasPaddr()
300 {
301 return privateFlags.isSet(VALID_PADDR);
302 }
303
304 Addr
305 getPaddr()
306 {
307 assert(privateFlags.isSet(VALID_PADDR));
308 return _paddr;
309 }
310
311 /**
312 * Accessor for size.
313 */
314 bool
315 hasSize()
316 {
317 return privateFlags.isSet(VALID_SIZE);
318 }
319
320 int
321 getSize()
322 {
323 assert(privateFlags.isSet(VALID_SIZE));
324 return _size;
325 }
326
327 /** Accessor for time. */
328 Tick
329 time() const
330 {
331 assert(privateFlags.isSet(VALID_PADDR|VALID_VADDR));
332 return _time;
333 }
334
335 void
336 time(Tick time)
337 {
338 assert(privateFlags.isSet(VALID_PADDR|VALID_VADDR));
339 _time = time;
340 }
341
342 /** Accessor for flags. */
343 Flags
344 getFlags()
345 {
346 assert(privateFlags.isSet(VALID_PADDR|VALID_VADDR));
347 return _flags;
348 }
349
350 /** Note that unlike other accessors, this function sets *specific
351 flags* (ORs them in); it does not assign its argument to the
352 _flags field. Thus this method should rightly be called
353 setFlags() and not just flags(). */
354 void
355 setFlags(Flags flags)
356 {
357 assert(privateFlags.isSet(VALID_PADDR|VALID_VADDR));
358 _flags.set(flags);
359 }
360
361 /** Accessor function for vaddr.*/
362 Addr
363 getVaddr()
364 {
365 assert(privateFlags.isSet(VALID_VADDR));
366 return _vaddr;
367 }
368
369 /** Accessor function for asid.*/
370 int
371 getAsid()
372 {
373 assert(privateFlags.isSet(VALID_VADDR));
374 return _asid;
375 }
376
377 /** Accessor function for asi.*/
378 uint8_t
379 getAsi()
380 {
381 assert(privateFlags.isSet(VALID_VADDR));
382 return _flags & ASI_BITS;
383 }
384
385 /** Accessor function to check if sc result is valid. */
386 bool
387 extraDataValid()
388 {
389 return privateFlags.isSet(VALID_EXTRA_DATA);
390 }
391
392 /** Accessor function for store conditional return value.*/
393 uint64_t
394 getExtraData() const
395 {
396 assert(privateFlags.isSet(VALID_EXTRA_DATA));
397 return _extraData;
398 }
399
400 /** Accessor function for store conditional return value.*/
401 void
402 setExtraData(uint64_t extraData)
403 {
404 _extraData = extraData;
405 privateFlags.set(VALID_EXTRA_DATA);
406 }
407
408 bool
409 hasContextId() const
410 {
411 return privateFlags.isSet(VALID_CONTEXT_ID);
412 }
413
414 /** Accessor function for context ID.*/
415 int
416 contextId() const
417 {
418 assert(privateFlags.isSet(VALID_CONTEXT_ID));
419 return _contextId;
420 }
421
422 /** Accessor function for thread ID. */
423 int
424 threadId() const
425 {
426 assert(privateFlags.isSet(VALID_THREAD_ID));
427 return _threadId;
428 }
429
430 bool
431 hasPC() const
432 {
433 return privateFlags.isSet(VALID_PC);
434 }
435
436 /** Accessor function for pc.*/
437 Addr
438 getPC() const
439 {
440 assert(privateFlags.isSet(VALID_PC));
441 return _pc;
442 }
443
444 /** Accessor functions for flags. Note that these are for testing
445 only; setting flags should be done via setFlags(). */
446 bool isUncacheable() const { return _flags.isSet(UNCACHEABLE); }
447 bool isInstFetch() const { return _flags.isSet(INST_FETCH); }
448 bool isPrefetch() const { return _flags.isSet(PREFETCH); }
449 bool isLLSC() const { return _flags.isSet(LLSC); }
450 bool isLocked() const { return _flags.isSet(LOCKED); }
451 bool isSwap() const { return _flags.isSet(MEM_SWAP|MEM_SWAP_COND); }
452 bool isCondSwap() const { return _flags.isSet(MEM_SWAP_COND); }
453 bool isMmapedIpr() const { return _flags.isSet(MMAPED_IPR); }
454
455 bool
456 isMisaligned() const
457 {
458 if (_flags.isSet(NO_ALIGN_FAULT))
459 return false;
460
461 if ((_vaddr & 0x1))
462 return true;
463
464 if (_flags.isSet(NO_HALF_WORD_ALIGN_FAULT))
465 return false;
466
467 if ((_vaddr & 0x2))
468 return true;
469
470 return false;
471 }
472};
473
474#endif // __MEM_REQUEST_HH__