1 /*
2 NetWinder Floating Point Emulator
3 (c) Rebel.com, 1998-1999
4 (c) Philip Blundell, 1998, 2001
5
6 Direct questions, comments to Scott Bambrough <scottb@netwinder.org>
7
8 This program is free software; you can redistribute it and/or modify
9 it under the terms of the GNU General Public License as published by
10 the Free Software Foundation; either version 2 of the License, or
11 (at your option) any later version.
12
13 This program is distributed in the hope that it will be useful,
14 but WITHOUT ANY WARRANTY; without even the implied warranty of
15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 GNU General Public License for more details.
17
18 You should have received a copy of the GNU General Public License
19 along with this program; if not, write to the Free Software
20 Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
21 */
22
23 #include "fpa11.h"
24 #include "softfloat.h"
25 #include "fpopcode.h"
26 #include "fpmodule.h"
27 #include "fpmodule.inl"
28
29 #include <linux/uaccess.h>
30
loadSingle(const unsigned int Fn,const unsigned int __user * pMem)31 static inline void loadSingle(const unsigned int Fn, const unsigned int __user *pMem)
32 {
33 FPA11 *fpa11 = GET_FPA11();
34 fpa11->fType[Fn] = typeSingle;
35 get_user(fpa11->fpreg[Fn].fSingle, pMem);
36 }
37
loadDouble(const unsigned int Fn,const unsigned int __user * pMem)38 static inline void loadDouble(const unsigned int Fn, const unsigned int __user *pMem)
39 {
40 FPA11 *fpa11 = GET_FPA11();
41 unsigned int *p;
42 p = (unsigned int *) &fpa11->fpreg[Fn].fDouble;
43 fpa11->fType[Fn] = typeDouble;
44 #ifdef __ARMEB__
45 get_user(p[0], &pMem[0]); /* sign & exponent */
46 get_user(p[1], &pMem[1]);
47 #else
48 get_user(p[0], &pMem[1]);
49 get_user(p[1], &pMem[0]); /* sign & exponent */
50 #endif
51 }
52
53 #ifdef CONFIG_FPE_NWFPE_XP
loadExtended(const unsigned int Fn,const unsigned int __user * pMem)54 static inline void loadExtended(const unsigned int Fn, const unsigned int __user *pMem)
55 {
56 FPA11 *fpa11 = GET_FPA11();
57 unsigned int *p;
58 p = (unsigned int *) &fpa11->fpreg[Fn].fExtended;
59 fpa11->fType[Fn] = typeExtended;
60 get_user(p[0], &pMem[0]); /* sign & exponent */
61 #ifdef __ARMEB__
62 get_user(p[1], &pMem[1]); /* ms bits */
63 get_user(p[2], &pMem[2]); /* ls bits */
64 #else
65 get_user(p[1], &pMem[2]); /* ls bits */
66 get_user(p[2], &pMem[1]); /* ms bits */
67 #endif
68 }
69 #endif
70
loadMultiple(const unsigned int Fn,const unsigned int __user * pMem)71 static inline void loadMultiple(const unsigned int Fn, const unsigned int __user *pMem)
72 {
73 FPA11 *fpa11 = GET_FPA11();
74 register unsigned int *p;
75 unsigned long x;
76
77 p = (unsigned int *) &(fpa11->fpreg[Fn]);
78 get_user(x, &pMem[0]);
79 fpa11->fType[Fn] = (x >> 14) & 0x00000003;
80
81 switch (fpa11->fType[Fn]) {
82 case typeSingle:
83 case typeDouble:
84 {
85 get_user(p[0], &pMem[2]); /* Single */
86 get_user(p[1], &pMem[1]); /* double msw */
87 p[2] = 0; /* empty */
88 }
89 break;
90
91 #ifdef CONFIG_FPE_NWFPE_XP
92 case typeExtended:
93 {
94 get_user(p[1], &pMem[2]);
95 get_user(p[2], &pMem[1]); /* msw */
96 p[0] = (x & 0x80003fff);
97 }
98 break;
99 #endif
100 }
101 }
102
storeSingle(struct roundingData * roundData,const unsigned int Fn,unsigned int __user * pMem)103 static inline void storeSingle(struct roundingData *roundData, const unsigned int Fn, unsigned int __user *pMem)
104 {
105 FPA11 *fpa11 = GET_FPA11();
106 union {
107 float32 f;
108 unsigned int i[1];
109 } val;
110
111 switch (fpa11->fType[Fn]) {
112 case typeDouble:
113 val.f = float64_to_float32(roundData, fpa11->fpreg[Fn].fDouble);
114 break;
115
116 #ifdef CONFIG_FPE_NWFPE_XP
117 case typeExtended:
118 val.f = floatx80_to_float32(roundData, fpa11->fpreg[Fn].fExtended);
119 break;
120 #endif
121
122 default:
123 val.f = fpa11->fpreg[Fn].fSingle;
124 }
125
126 put_user(val.i[0], pMem);
127 }
128
storeDouble(struct roundingData * roundData,const unsigned int Fn,unsigned int __user * pMem)129 static inline void storeDouble(struct roundingData *roundData, const unsigned int Fn, unsigned int __user *pMem)
130 {
131 FPA11 *fpa11 = GET_FPA11();
132 union {
133 float64 f;
134 unsigned int i[2];
135 } val;
136
137 switch (fpa11->fType[Fn]) {
138 case typeSingle:
139 val.f = float32_to_float64(fpa11->fpreg[Fn].fSingle);
140 break;
141
142 #ifdef CONFIG_FPE_NWFPE_XP
143 case typeExtended:
144 val.f = floatx80_to_float64(roundData, fpa11->fpreg[Fn].fExtended);
145 break;
146 #endif
147
148 default:
149 val.f = fpa11->fpreg[Fn].fDouble;
150 }
151
152 #ifdef __ARMEB__
153 put_user(val.i[0], &pMem[0]); /* msw */
154 put_user(val.i[1], &pMem[1]); /* lsw */
155 #else
156 put_user(val.i[1], &pMem[0]); /* msw */
157 put_user(val.i[0], &pMem[1]); /* lsw */
158 #endif
159 }
160
161 #ifdef CONFIG_FPE_NWFPE_XP
storeExtended(const unsigned int Fn,unsigned int __user * pMem)162 static inline void storeExtended(const unsigned int Fn, unsigned int __user *pMem)
163 {
164 FPA11 *fpa11 = GET_FPA11();
165 union {
166 floatx80 f;
167 unsigned int i[3];
168 } val;
169
170 switch (fpa11->fType[Fn]) {
171 case typeSingle:
172 val.f = float32_to_floatx80(fpa11->fpreg[Fn].fSingle);
173 break;
174
175 case typeDouble:
176 val.f = float64_to_floatx80(fpa11->fpreg[Fn].fDouble);
177 break;
178
179 default:
180 val.f = fpa11->fpreg[Fn].fExtended;
181 }
182
183 put_user(val.i[0], &pMem[0]); /* sign & exp */
184 #ifdef __ARMEB__
185 put_user(val.i[1], &pMem[1]); /* msw */
186 put_user(val.i[2], &pMem[2]);
187 #else
188 put_user(val.i[1], &pMem[2]);
189 put_user(val.i[2], &pMem[1]); /* msw */
190 #endif
191 }
192 #endif
193
storeMultiple(const unsigned int Fn,unsigned int __user * pMem)194 static inline void storeMultiple(const unsigned int Fn, unsigned int __user *pMem)
195 {
196 FPA11 *fpa11 = GET_FPA11();
197 register unsigned int nType, *p;
198
199 p = (unsigned int *) &(fpa11->fpreg[Fn]);
200 nType = fpa11->fType[Fn];
201
202 switch (nType) {
203 case typeSingle:
204 case typeDouble:
205 {
206 put_user(p[0], &pMem[2]); /* single */
207 put_user(p[1], &pMem[1]); /* double msw */
208 put_user(nType << 14, &pMem[0]);
209 }
210 break;
211
212 #ifdef CONFIG_FPE_NWFPE_XP
213 case typeExtended:
214 {
215 put_user(p[2], &pMem[1]); /* msw */
216 put_user(p[1], &pMem[2]);
217 put_user((p[0] & 0x80003fff) | (nType << 14), &pMem[0]);
218 }
219 break;
220 #endif
221 }
222 }
223
PerformLDF(const unsigned int opcode)224 unsigned int PerformLDF(const unsigned int opcode)
225 {
226 unsigned int __user *pBase, *pAddress, *pFinal;
227 unsigned int nRc = 1, write_back = WRITE_BACK(opcode);
228
229 pBase = (unsigned int __user *) readRegister(getRn(opcode));
230 if (REG_PC == getRn(opcode)) {
231 pBase += 2;
232 write_back = 0;
233 }
234
235 pFinal = pBase;
236 if (BIT_UP_SET(opcode))
237 pFinal += getOffset(opcode);
238 else
239 pFinal -= getOffset(opcode);
240
241 if (PREINDEXED(opcode))
242 pAddress = pFinal;
243 else
244 pAddress = pBase;
245
246 switch (opcode & MASK_TRANSFER_LENGTH) {
247 case TRANSFER_SINGLE:
248 loadSingle(getFd(opcode), pAddress);
249 break;
250 case TRANSFER_DOUBLE:
251 loadDouble(getFd(opcode), pAddress);
252 break;
253 #ifdef CONFIG_FPE_NWFPE_XP
254 case TRANSFER_EXTENDED:
255 loadExtended(getFd(opcode), pAddress);
256 break;
257 #endif
258 default:
259 nRc = 0;
260 }
261
262 if (write_back)
263 writeRegister(getRn(opcode), (unsigned long) pFinal);
264 return nRc;
265 }
266
PerformSTF(const unsigned int opcode)267 unsigned int PerformSTF(const unsigned int opcode)
268 {
269 unsigned int __user *pBase, *pAddress, *pFinal;
270 unsigned int nRc = 1, write_back = WRITE_BACK(opcode);
271 struct roundingData roundData;
272
273 roundData.mode = SetRoundingMode(opcode);
274 roundData.precision = SetRoundingPrecision(opcode);
275 roundData.exception = 0;
276
277 pBase = (unsigned int __user *) readRegister(getRn(opcode));
278 if (REG_PC == getRn(opcode)) {
279 pBase += 2;
280 write_back = 0;
281 }
282
283 pFinal = pBase;
284 if (BIT_UP_SET(opcode))
285 pFinal += getOffset(opcode);
286 else
287 pFinal -= getOffset(opcode);
288
289 if (PREINDEXED(opcode))
290 pAddress = pFinal;
291 else
292 pAddress = pBase;
293
294 switch (opcode & MASK_TRANSFER_LENGTH) {
295 case TRANSFER_SINGLE:
296 storeSingle(&roundData, getFd(opcode), pAddress);
297 break;
298 case TRANSFER_DOUBLE:
299 storeDouble(&roundData, getFd(opcode), pAddress);
300 break;
301 #ifdef CONFIG_FPE_NWFPE_XP
302 case TRANSFER_EXTENDED:
303 storeExtended(getFd(opcode), pAddress);
304 break;
305 #endif
306 default:
307 nRc = 0;
308 }
309
310 if (roundData.exception)
311 float_raise(roundData.exception);
312
313 if (write_back)
314 writeRegister(getRn(opcode), (unsigned long) pFinal);
315 return nRc;
316 }
317
PerformLFM(const unsigned int opcode)318 unsigned int PerformLFM(const unsigned int opcode)
319 {
320 unsigned int __user *pBase, *pAddress, *pFinal;
321 unsigned int i, Fd, write_back = WRITE_BACK(opcode);
322
323 pBase = (unsigned int __user *) readRegister(getRn(opcode));
324 if (REG_PC == getRn(opcode)) {
325 pBase += 2;
326 write_back = 0;
327 }
328
329 pFinal = pBase;
330 if (BIT_UP_SET(opcode))
331 pFinal += getOffset(opcode);
332 else
333 pFinal -= getOffset(opcode);
334
335 if (PREINDEXED(opcode))
336 pAddress = pFinal;
337 else
338 pAddress = pBase;
339
340 Fd = getFd(opcode);
341 for (i = getRegisterCount(opcode); i > 0; i--) {
342 loadMultiple(Fd, pAddress);
343 pAddress += 3;
344 Fd++;
345 if (Fd == 8)
346 Fd = 0;
347 }
348
349 if (write_back)
350 writeRegister(getRn(opcode), (unsigned long) pFinal);
351 return 1;
352 }
353
PerformSFM(const unsigned int opcode)354 unsigned int PerformSFM(const unsigned int opcode)
355 {
356 unsigned int __user *pBase, *pAddress, *pFinal;
357 unsigned int i, Fd, write_back = WRITE_BACK(opcode);
358
359 pBase = (unsigned int __user *) readRegister(getRn(opcode));
360 if (REG_PC == getRn(opcode)) {
361 pBase += 2;
362 write_back = 0;
363 }
364
365 pFinal = pBase;
366 if (BIT_UP_SET(opcode))
367 pFinal += getOffset(opcode);
368 else
369 pFinal -= getOffset(opcode);
370
371 if (PREINDEXED(opcode))
372 pAddress = pFinal;
373 else
374 pAddress = pBase;
375
376 Fd = getFd(opcode);
377 for (i = getRegisterCount(opcode); i > 0; i--) {
378 storeMultiple(Fd, pAddress);
379 pAddress += 3;
380 Fd++;
381 if (Fd == 8)
382 Fd = 0;
383 }
384
385 if (write_back)
386 writeRegister(getRn(opcode), (unsigned long) pFinal);
387 return 1;
388 }
389
EmulateCPDT(const unsigned int opcode)390 unsigned int EmulateCPDT(const unsigned int opcode)
391 {
392 unsigned int nRc = 0;
393
394 if (LDF_OP(opcode)) {
395 nRc = PerformLDF(opcode);
396 } else if (LFM_OP(opcode)) {
397 nRc = PerformLFM(opcode);
398 } else if (STF_OP(opcode)) {
399 nRc = PerformSTF(opcode);
400 } else if (SFM_OP(opcode)) {
401 nRc = PerformSFM(opcode);
402 } else {
403 nRc = 0;
404 }
405
406 return nRc;
407 }
408