1 /* armvirt.c -- ARMulator virtual memory interace: ARM6 Instruction Emulator.
2 Copyright (C) 1994 Advanced RISC Machines Ltd.
4 This program is free software; you can redistribute it and/or modify
5 it under the terms of the GNU General Public License as published by
6 the Free Software Foundation; either version 2 of the License, or
7 (at your option) any later version.
9 This program is distributed in the hope that it will be useful,
10 but WITHOUT ANY WARRANTY; without even the implied warranty of
11 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 GNU General Public License for more details.
14 You should have received a copy of the GNU General Public License
15 along with this program; if not, write to the Free Software
16 Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */
18 /* This file contains a complete ARMulator memory model, modelling a
19 "virtual memory" system. A much simpler model can be found in armfast.c,
20 and that model goes faster too, but has a fixed amount of memory. This
21 model's memory has 64K pages, allocated on demand from a 64K entry page
22 table. The routines PutWord and GetWord implement this. Pages are never
23 freed as they might be needed again. A single area of memory may be
24 defined to generate aborts. */
31 #ifdef VALIDATE /* for running the validate suite */
32 #define TUBE 48 * 1024 * 1024 /* write a char on the screen */
38 #ifdef ABORTS /* the memory system will abort */
39 /* For the old test suite Abort between 32 Kbytes and 32 Mbytes
40 For the new test suite Abort between 8 Mbytes and 26 Mbytes */
41 /* #define LOWABORT 32 * 1024
42 #define HIGHABORT 32 * 1024 * 1024 */
43 #define LOWABORT 8 * 1024 * 1024
44 #define HIGHABORT 26 * 1024 * 1024
48 #define NUMPAGES 64 * 1024
49 #define PAGESIZE 64 * 1024
51 #define OFFSETBITS 0xffff
53 int SWI_vector_installed
= FALSE
;
55 /***************************************************************************\
56 * Get a Word from Virtual Memory, maybe allocating the page *
57 \***************************************************************************/
60 GetWord (ARMul_State
* state
, ARMword address
, int check
)
67 XScale_check_memacc (state
, &address
, 0);
69 page
= address
>> PAGEBITS
;
70 offset
= (address
& OFFSETBITS
) >> 2;
71 pagetable
= (ARMword
**) state
->MemDataPtr
;
72 pageptr
= *(pagetable
+ page
);
76 pageptr
= (ARMword
*) malloc (PAGESIZE
);
80 perror ("ARMulator can't allocate VM page");
84 *(pagetable
+ page
) = pageptr
;
87 return *(pageptr
+ offset
);
90 /***************************************************************************\
91 * Put a Word into Virtual Memory, maybe allocating the page *
92 \***************************************************************************/
95 PutWord (ARMul_State
* state
, ARMword address
, ARMword data
, int check
)
102 XScale_check_memacc (state
, &address
, 1);
104 page
= address
>> PAGEBITS
;
105 offset
= (address
& OFFSETBITS
) >> 2;
106 pagetable
= (ARMword
**) state
->MemDataPtr
;
107 pageptr
= *(pagetable
+ page
);
111 pageptr
= (ARMword
*) malloc (PAGESIZE
);
114 perror ("ARMulator can't allocate VM page");
118 *(pagetable
+ page
) = pageptr
;
122 SWI_vector_installed
= TRUE
;
124 *(pageptr
+ offset
) = data
;
127 /***************************************************************************\
128 * Initialise the memory interface *
129 \***************************************************************************/
132 ARMul_MemoryInit (ARMul_State
* state
, unsigned long initmemsize
)
138 state
->MemSize
= initmemsize
;
140 pagetable
= (ARMword
**) malloc (sizeof (ARMword
) * NUMPAGES
);
142 if (pagetable
== NULL
)
145 for (page
= 0; page
< NUMPAGES
; page
++)
146 *(pagetable
+ page
) = NULL
;
148 state
->MemDataPtr
= (unsigned char *) pagetable
;
150 ARMul_ConsolePrint (state
, ", 4 Gb memory");
155 /***************************************************************************\
156 * Remove the memory interface *
157 \***************************************************************************/
160 ARMul_MemoryExit (ARMul_State
* state
)
166 pagetable
= (ARMword
**) state
->MemDataPtr
;
167 for (page
= 0; page
< NUMPAGES
; page
++)
169 pageptr
= *(pagetable
+ page
);
171 free ((char *) pageptr
);
173 free ((char *) pagetable
);
177 /***************************************************************************\
178 * ReLoad Instruction *
179 \***************************************************************************/
182 ARMul_ReLoadInstr (ARMul_State
* state
, ARMword address
, ARMword isize
)
185 if (address
>= LOWABORT
&& address
< HIGHABORT
)
187 ARMul_PREFETCHABORT (address
);
188 return ARMul_ABORTWORD
;
196 if ((isize
== 2) && (address
& 0x2))
198 /* We return the next two halfwords: */
199 ARMword lo
= GetWord (state
, address
, FALSE
);
200 ARMword hi
= GetWord (state
, address
+ 4, FALSE
);
202 if (state
->bigendSig
== HIGH
)
203 return (lo
<< 16) | (hi
>> 16);
205 return ((hi
& 0xFFFF) << 16) | (lo
>> 16);
208 return GetWord (state
, address
, TRUE
);
211 /***************************************************************************\
212 * Load Instruction, Sequential Cycle *
213 \***************************************************************************/
215 ARMword
ARMul_LoadInstrS (ARMul_State
* state
, ARMword address
, ARMword isize
)
220 if ((state
->NumScycles
& HOURGLASS_RATE
) == 0)
226 return ARMul_ReLoadInstr (state
, address
, isize
);
229 /***************************************************************************\
230 * Load Instruction, Non Sequential Cycle *
231 \***************************************************************************/
233 ARMword
ARMul_LoadInstrN (ARMul_State
* state
, ARMword address
, ARMword isize
)
237 return ARMul_ReLoadInstr (state
, address
, isize
);
240 /***************************************************************************\
241 * Read Word (but don't tell anyone!) *
242 \***************************************************************************/
244 ARMword
ARMul_ReadWord (ARMul_State
* state
, ARMword address
)
247 if (address
>= LOWABORT
&& address
< HIGHABORT
)
249 ARMul_DATAABORT (address
);
250 return ARMul_ABORTWORD
;
258 return GetWord (state
, address
, TRUE
);
261 /***************************************************************************\
262 * Load Word, Sequential Cycle *
263 \***************************************************************************/
265 ARMword
ARMul_LoadWordS (ARMul_State
* state
, ARMword address
)
269 return ARMul_ReadWord (state
, address
);
272 /***************************************************************************\
273 * Load Word, Non Sequential Cycle *
274 \***************************************************************************/
276 ARMword
ARMul_LoadWordN (ARMul_State
* state
, ARMword address
)
280 return ARMul_ReadWord (state
, address
);
283 /***************************************************************************\
284 * Load Halfword, (Non Sequential Cycle) *
285 \***************************************************************************/
287 ARMword
ARMul_LoadHalfWord (ARMul_State
* state
, ARMword address
)
289 ARMword temp
, offset
;
293 temp
= ARMul_ReadWord (state
, address
);
294 offset
= (((ARMword
) state
->bigendSig
* 2) ^ (address
& 2)) << 3; /* bit offset into the word */
296 return (temp
>> offset
) & 0xffff;
299 /***************************************************************************\
300 * Read Byte (but don't tell anyone!) *
301 \***************************************************************************/
303 ARMword
ARMul_ReadByte (ARMul_State
* state
, ARMword address
)
305 ARMword temp
, offset
;
307 temp
= ARMul_ReadWord (state
, address
);
308 offset
= (((ARMword
) state
->bigendSig
* 3) ^ (address
& 3)) << 3; /* bit offset into the word */
310 return (temp
>> offset
& 0xffL
);
313 /***************************************************************************\
314 * Load Byte, (Non Sequential Cycle) *
315 \***************************************************************************/
317 ARMword
ARMul_LoadByte (ARMul_State
* state
, ARMword address
)
321 return ARMul_ReadByte (state
, address
);
324 /***************************************************************************\
325 * Write Word (but don't tell anyone!) *
326 \***************************************************************************/
329 ARMul_WriteWord (ARMul_State
* state
, ARMword address
, ARMword data
)
332 if (address
>= LOWABORT
&& address
< HIGHABORT
)
334 ARMul_DATAABORT (address
);
343 PutWord (state
, address
, data
, TRUE
);
346 /***************************************************************************\
347 * Store Word, Sequential Cycle *
348 \***************************************************************************/
351 ARMul_StoreWordS (ARMul_State
* state
, ARMword address
, ARMword data
)
355 ARMul_WriteWord (state
, address
, data
);
358 /***************************************************************************\
359 * Store Word, Non Sequential Cycle *
360 \***************************************************************************/
363 ARMul_StoreWordN (ARMul_State
* state
, ARMword address
, ARMword data
)
367 ARMul_WriteWord (state
, address
, data
);
370 /***************************************************************************\
371 * Store HalfWord, (Non Sequential Cycle) *
372 \***************************************************************************/
375 ARMul_StoreHalfWord (ARMul_State
* state
, ARMword address
, ARMword data
)
377 ARMword temp
, offset
;
385 state
->Emulate
= FALSE
;
387 (void) putc ((char) data
, stderr
); /* Write Char */
392 temp
= ARMul_ReadWord (state
, address
);
393 offset
= (((ARMword
) state
->bigendSig
* 2) ^ (address
& 2)) << 3; /* bit offset into the word */
395 PutWord (state
, address
,
396 (temp
& ~(0xffffL
<< offset
)) | ((data
& 0xffffL
) << offset
),
400 /***************************************************************************\
401 * Write Byte (but don't tell anyone!) *
402 \***************************************************************************/
405 ARMul_WriteByte (ARMul_State
* state
, ARMword address
, ARMword data
)
407 ARMword temp
, offset
;
409 temp
= ARMul_ReadWord (state
, address
);
410 offset
= (((ARMword
) state
->bigendSig
* 3) ^ (address
& 3)) << 3; /* bit offset into the word */
412 PutWord (state
, address
,
413 (temp
& ~(0xffL
<< offset
)) | ((data
& 0xffL
) << offset
),
417 /***************************************************************************\
418 * Store Byte, (Non Sequential Cycle) *
419 \***************************************************************************/
422 ARMul_StoreByte (ARMul_State
* state
, ARMword address
, ARMword data
)
430 state
->Emulate
= FALSE
;
432 (void) putc ((char) data
, stderr
); /* Write Char */
437 ARMul_WriteByte (state
, address
, data
);
440 /***************************************************************************\
441 * Swap Word, (Two Non Sequential Cycles) *
442 \***************************************************************************/
444 ARMword
ARMul_SwapWord (ARMul_State
* state
, ARMword address
, ARMword data
)
450 temp
= ARMul_ReadWord (state
, address
);
454 PutWord (state
, address
, data
, TRUE
);
459 /***************************************************************************\
460 * Swap Byte, (Two Non Sequential Cycles) *
461 \***************************************************************************/
463 ARMword
ARMul_SwapByte (ARMul_State
* state
, ARMword address
, ARMword data
)
467 temp
= ARMul_LoadByte (state
, address
);
468 ARMul_StoreByte (state
, address
, data
);
473 /***************************************************************************\
475 \***************************************************************************/
478 ARMul_Icycles (ARMul_State
* state
, unsigned number
, ARMword address ATTRIBUTE_UNUSED
)
480 state
->NumIcycles
+= number
;
484 /***************************************************************************\
486 \***************************************************************************/
489 ARMul_Ccycles (ARMul_State
* state
, unsigned number
, ARMword address ATTRIBUTE_UNUSED
)
491 state
->NumCcycles
+= number
;
496 /* Read a byte. Do not check for alignment or access errors. */
499 ARMul_SafeReadByte (ARMul_State
* state
, ARMword address
)
501 ARMword temp
, offset
;
503 temp
= GetWord (state
, address
, FALSE
);
504 offset
= (((ARMword
) state
->bigendSig
* 3) ^ (address
& 3)) << 3;
506 return (temp
>> offset
& 0xffL
);
510 ARMul_SafeWriteByte (ARMul_State
* state
, ARMword address
, ARMword data
)
512 ARMword temp
, offset
;
514 temp
= GetWord (state
, address
, FALSE
);
515 offset
= (((ARMword
) state
->bigendSig
* 3) ^ (address
& 3)) << 3;
517 PutWord (state
, address
,
518 (temp
& ~(0xffL
<< offset
)) | ((data
& 0xffL
) << offset
),