xref: /netbsd-src/external/gpl3/gdb/dist/sim/arm/arminit.c (revision a5847cc334d9a7029f6352b847e9e8d71a0f9e0c)
1 /*  arminit.c -- ARMulator initialization:  ARM6 Instruction Emulator.
2     Copyright (C) 1994 Advanced RISC Machines Ltd.
3 
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.
8 
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.
13 
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., 51 Franklin Street - Fifth Floor, Boston, MA 02110-1301, USA. */
17 
18 #include <string.h>
19 
20 #include "armdefs.h"
21 #include "armemu.h"
22 #include "dbg_rdi.h"
23 
24 /***************************************************************************\
25 *                 Definitions for the emulator architecture                 *
26 \***************************************************************************/
27 
28 void ARMul_EmulateInit (void);
29 ARMul_State *ARMul_NewState (void);
30 void ARMul_Reset (ARMul_State * state);
31 ARMword ARMul_DoCycle (ARMul_State * state);
32 unsigned ARMul_DoCoPro (ARMul_State * state);
33 ARMword ARMul_DoProg (ARMul_State * state);
34 ARMword ARMul_DoInstr (ARMul_State * state);
35 void ARMul_Abort (ARMul_State * state, ARMword address);
36 
37 unsigned ARMul_MultTable[32] =
38   { 1, 2, 2, 3, 3, 4, 4, 5, 5, 6, 6, 7, 7, 8, 8, 9, 9,
39   10, 10, 11, 11, 12, 12, 13, 13, 14, 14, 15, 15, 16, 16, 16
40 };
41 ARMword ARMul_ImmedTable[4096];	/* immediate DP LHS values */
42 char ARMul_BitList[256];	/* number of bits in a byte table */
43 
44 /***************************************************************************\
45 *         Call this routine once to set up the emulator's tables.           *
46 \***************************************************************************/
47 
48 void
49 ARMul_EmulateInit (void)
50 {
51   unsigned long i, j;
52 
53   for (i = 0; i < 4096; i++)
54     {				/* the values of 12 bit dp rhs's */
55       ARMul_ImmedTable[i] = ROTATER (i & 0xffL, (i >> 7L) & 0x1eL);
56     }
57 
58   for (i = 0; i < 256; ARMul_BitList[i++] = 0);	/* how many bits in LSM */
59   for (j = 1; j < 256; j <<= 1)
60     for (i = 0; i < 256; i++)
61       if ((i & j) > 0)
62 	ARMul_BitList[i]++;
63 
64   for (i = 0; i < 256; i++)
65     ARMul_BitList[i] *= 4;	/* you always need 4 times these values */
66 
67 }
68 
69 /***************************************************************************\
70 *            Returns a new instantiation of the ARMulator's state           *
71 \***************************************************************************/
72 
73 ARMul_State *
74 ARMul_NewState (void)
75 {
76   ARMul_State *state;
77   unsigned i, j;
78 
79   state = (ARMul_State *) malloc (sizeof (ARMul_State));
80   memset (state, 0, sizeof (ARMul_State));
81 
82   state->Emulate = RUN;
83   for (i = 0; i < 16; i++)
84     {
85       state->Reg[i] = 0;
86       for (j = 0; j < 7; j++)
87 	state->RegBank[j][i] = 0;
88     }
89   for (i = 0; i < 7; i++)
90     state->Spsr[i] = 0;
91 
92   /* state->Mode = USER26MODE;  */
93   state->Mode = USER32MODE;
94 
95   state->CallDebug = FALSE;
96   state->Debug = FALSE;
97   state->VectorCatch = 0;
98   state->Aborted = FALSE;
99   state->Reseted = FALSE;
100   state->Inted = 3;
101   state->LastInted = 3;
102 
103   state->MemDataPtr = NULL;
104   state->MemInPtr = NULL;
105   state->MemOutPtr = NULL;
106   state->MemSparePtr = NULL;
107   state->MemSize = 0;
108 
109   state->OSptr = NULL;
110   state->CommandLine = NULL;
111 
112   state->CP14R0_CCD = -1;
113   state->LastTime = 0;
114 
115   state->EventSet = 0;
116   state->Now = 0;
117   state->EventPtr = (struct EventNode **) malloc ((unsigned) EVENTLISTSIZE *
118 						  sizeof (struct EventNode
119 							  *));
120   for (i = 0; i < EVENTLISTSIZE; i++)
121     *(state->EventPtr + i) = NULL;
122 
123   state->prog32Sig = HIGH;
124   state->data32Sig = HIGH;
125 
126   state->lateabtSig = LOW;
127   state->bigendSig = LOW;
128 
129   state->is_v4 = LOW;
130   state->is_v5 = LOW;
131   state->is_v5e = LOW;
132   state->is_XScale = LOW;
133   state->is_iWMMXt = LOW;
134   state->is_v6 = LOW;
135 
136   ARMul_Reset (state);
137 
138   return state;
139 }
140 
141 /***************************************************************************\
142   Call this routine to set ARMulator to model certain processor properities
143 \***************************************************************************/
144 
145 void
146 ARMul_SelectProcessor (ARMul_State * state, unsigned properties)
147 {
148   if (properties & ARM_Fix26_Prop)
149     {
150       state->prog32Sig = LOW;
151       state->data32Sig = LOW;
152     }
153   else
154     {
155       state->prog32Sig = HIGH;
156       state->data32Sig = HIGH;
157     }
158 
159   state->lateabtSig = LOW;
160 
161   state->is_v4 = (properties & (ARM_v4_Prop | ARM_v5_Prop)) ? HIGH : LOW;
162   state->is_v5 = (properties & ARM_v5_Prop) ? HIGH : LOW;
163   state->is_v5e = (properties & ARM_v5e_Prop) ? HIGH : LOW;
164   state->is_XScale = (properties & ARM_XScale_Prop) ? HIGH : LOW;
165   state->is_iWMMXt = (properties & ARM_iWMMXt_Prop) ? HIGH : LOW;
166   state->is_ep9312 = (properties & ARM_ep9312_Prop) ? HIGH : LOW;
167   state->is_v6 = (properties & ARM_v6_Prop) ? HIGH : LOW;
168 
169   /* Only initialse the coprocessor support once we
170      know what kind of chip we are dealing with.  */
171   ARMul_CoProInit (state);
172 }
173 
174 /***************************************************************************\
175 * Call this routine to set up the initial machine state (or perform a RESET *
176 \***************************************************************************/
177 
178 void
179 ARMul_Reset (ARMul_State * state)
180 {
181   state->NextInstr = 0;
182 
183   if (state->prog32Sig)
184     {
185       state->Reg[15] = 0;
186       state->Cpsr = INTBITS | SVC32MODE;
187       state->Mode = SVC32MODE;
188     }
189   else
190     {
191       state->Reg[15] = R15INTBITS | SVC26MODE;
192       state->Cpsr = INTBITS | SVC26MODE;
193       state->Mode = SVC26MODE;
194     }
195 
196   ARMul_CPSRAltered (state);
197   state->Bank = SVCBANK;
198 
199   FLUSHPIPE;
200 
201   state->EndCondition = 0;
202   state->ErrorCode = 0;
203 
204   state->Exception = FALSE;
205   state->NresetSig = HIGH;
206   state->NfiqSig = HIGH;
207   state->NirqSig = HIGH;
208   state->NtransSig = (state->Mode & 3) ? HIGH : LOW;
209   state->abortSig = LOW;
210   state->AbortAddr = 1;
211 
212   state->NumInstrs = 0;
213   state->NumNcycles = 0;
214   state->NumScycles = 0;
215   state->NumIcycles = 0;
216   state->NumCcycles = 0;
217   state->NumFcycles = 0;
218 #ifdef ASIM
219   (void) ARMul_MemoryInit ();
220   ARMul_OSInit (state);
221 #endif
222 }
223 
224 
225 /***************************************************************************\
226 * Emulate the execution of an entire program.  Start the correct emulator   *
227 * (Emulate26 for a 26 bit ARM and Emulate32 for a 32 bit ARM), return the   *
228 * address of the last instruction that is executed.                         *
229 \***************************************************************************/
230 
231 ARMword
232 ARMul_DoProg (ARMul_State * state)
233 {
234   ARMword pc = 0;
235 
236   state->Emulate = RUN;
237   while (state->Emulate != STOP)
238     {
239       state->Emulate = RUN;
240       if (state->prog32Sig && ARMul_MODE32BIT)
241 	pc = ARMul_Emulate32 (state);
242       else
243 	pc = ARMul_Emulate26 (state);
244     }
245   return (pc);
246 }
247 
248 /***************************************************************************\
249 * Emulate the execution of one instruction.  Start the correct emulator     *
250 * (Emulate26 for a 26 bit ARM and Emulate32 for a 32 bit ARM), return the   *
251 * address of the instruction that is executed.                              *
252 \***************************************************************************/
253 
254 ARMword
255 ARMul_DoInstr (ARMul_State * state)
256 {
257   ARMword pc = 0;
258 
259   state->Emulate = ONCE;
260   if (state->prog32Sig && ARMul_MODE32BIT)
261     pc = ARMul_Emulate32 (state);
262   else
263     pc = ARMul_Emulate26 (state);
264 
265   return (pc);
266 }
267 
268 /***************************************************************************\
269 * This routine causes an Abort to occur, including selecting the correct    *
270 * mode, register bank, and the saving of registers.  Call with the          *
271 * appropriate vector's memory address (0,4,8 ....)                          *
272 \***************************************************************************/
273 
274 void
275 ARMul_Abort (ARMul_State * state, ARMword vector)
276 {
277   ARMword temp;
278   int isize = INSN_SIZE;
279   int esize = (TFLAG ? 0 : 4);
280   int e2size = (TFLAG ? -4 : 0);
281 
282   state->Aborted = FALSE;
283 
284   if (ARMul_OSException (state, vector, ARMul_GetPC (state)))
285     return;
286 
287   if (state->prog32Sig)
288     if (ARMul_MODE26BIT)
289       temp = R15PC;
290     else
291       temp = state->Reg[15];
292   else
293     temp = R15PC | ECC | ER15INT | EMODE;
294 
295   switch (vector)
296     {
297     case ARMul_ResetV:		/* RESET */
298       SETABORT (INTBITS, state->prog32Sig ? SVC32MODE : SVC26MODE, 0);
299       break;
300     case ARMul_UndefinedInstrV:	/* Undefined Instruction */
301       SETABORT (IBIT, state->prog32Sig ? UNDEF32MODE : SVC26MODE, isize);
302       break;
303     case ARMul_SWIV:		/* Software Interrupt */
304       SETABORT (IBIT, state->prog32Sig ? SVC32MODE : SVC26MODE, isize);
305       break;
306     case ARMul_PrefetchAbortV:	/* Prefetch Abort */
307       state->AbortAddr = 1;
308       SETABORT (IBIT, state->prog32Sig ? ABORT32MODE : SVC26MODE, esize);
309       break;
310     case ARMul_DataAbortV:	/* Data Abort */
311       SETABORT (IBIT, state->prog32Sig ? ABORT32MODE : SVC26MODE, e2size);
312       break;
313     case ARMul_AddrExceptnV:	/* Address Exception */
314       SETABORT (IBIT, SVC26MODE, isize);
315       break;
316     case ARMul_IRQV:		/* IRQ */
317       if (   ! state->is_XScale
318 	  || ! state->CPRead[13] (state, 0, & temp)
319 	  || (temp & ARMul_CP13_R0_IRQ))
320         SETABORT (IBIT, state->prog32Sig ? IRQ32MODE : IRQ26MODE, esize);
321       break;
322     case ARMul_FIQV:		/* FIQ */
323       if (   ! state->is_XScale
324 	  || ! state->CPRead[13] (state, 0, & temp)
325 	  || (temp & ARMul_CP13_R0_FIQ))
326         SETABORT (INTBITS, state->prog32Sig ? FIQ32MODE : FIQ26MODE, esize);
327       break;
328     }
329   if (ARMul_MODE32BIT)
330     ARMul_SetR15 (state, vector);
331   else
332     ARMul_SetR15 (state, R15CCINTMODE | vector);
333 
334   if (ARMul_ReadWord (state, ARMul_GetPC (state)) == 0)
335     {
336       /* No vector has been installed.  Rather than simulating whatever
337 	 random bits might happen to be at address 0x20 onwards we elect
338 	 to stop.  */
339       switch (vector)
340 	{
341 	case ARMul_ResetV: state->EndCondition = RDIError_Reset; break;
342 	case ARMul_UndefinedInstrV: state->EndCondition = RDIError_UndefinedInstruction; break;
343 	case ARMul_SWIV: state->EndCondition = RDIError_SoftwareInterrupt; break;
344 	case ARMul_PrefetchAbortV: state->EndCondition = RDIError_PrefetchAbort; break;
345 	case ARMul_DataAbortV: state->EndCondition = RDIError_DataAbort; break;
346 	case ARMul_AddrExceptnV: state->EndCondition = RDIError_AddressException; break;
347 	case ARMul_IRQV: state->EndCondition = RDIError_IRQ; break;
348 	case ARMul_FIQV: state->EndCondition = RDIError_FIQ; break;
349 	default: break;
350 	}
351       state->Emulate = FALSE;
352     }
353 }
354