1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3 NetWinder Floating Point Emulator
4 (c) Rebel.com, 1998-1999
5 (c) Philip Blundell, 1998, 2001
6
7 Direct questions, comments to Scott Bambrough <scottb@netwinder.org>
8
9 */
10
11 #include "fpa11.h"
12 #include "softfloat.h"
13 #include "fpopcode.h"
14 #include "fpmodule.h"
15 #include "fpmodule.inl"
16
17 #include <linux/uaccess.h>
18
loadSingle(const unsigned int Fn,const unsigned int __user * pMem)19 static inline void loadSingle(const unsigned int Fn, const unsigned int __user *pMem)
20 {
21 FPA11 *fpa11 = GET_FPA11();
22 fpa11->fType[Fn] = typeSingle;
23 get_user(fpa11->fpreg[Fn].fSingle, pMem);
24 }
25
loadDouble(const unsigned int Fn,const unsigned int __user * pMem)26 static inline void loadDouble(const unsigned int Fn, const unsigned int __user *pMem)
27 {
28 FPA11 *fpa11 = GET_FPA11();
29 unsigned int *p;
30 p = (unsigned int *) &fpa11->fpreg[Fn].fDouble;
31 fpa11->fType[Fn] = typeDouble;
32 #ifdef __ARMEB__
33 get_user(p[0], &pMem[0]); /* sign & exponent */
34 get_user(p[1], &pMem[1]);
35 #else
36 get_user(p[0], &pMem[1]);
37 get_user(p[1], &pMem[0]); /* sign & exponent */
38 #endif
39 }
40
41 #ifdef CONFIG_FPE_NWFPE_XP
loadExtended(const unsigned int Fn,const unsigned int __user * pMem)42 static inline void loadExtended(const unsigned int Fn, const unsigned int __user *pMem)
43 {
44 FPA11 *fpa11 = GET_FPA11();
45 unsigned int *p;
46 p = (unsigned int *) &fpa11->fpreg[Fn].fExtended;
47 fpa11->fType[Fn] = typeExtended;
48 get_user(p[0], &pMem[0]); /* sign & exponent */
49 #ifdef __ARMEB__
50 get_user(p[1], &pMem[1]); /* ms bits */
51 get_user(p[2], &pMem[2]); /* ls bits */
52 #else
53 get_user(p[1], &pMem[2]); /* ls bits */
54 get_user(p[2], &pMem[1]); /* ms bits */
55 #endif
56 }
57 #endif
58
loadMultiple(const unsigned int Fn,const unsigned int __user * pMem)59 static inline void loadMultiple(const unsigned int Fn, const unsigned int __user *pMem)
60 {
61 FPA11 *fpa11 = GET_FPA11();
62 register unsigned int *p;
63 unsigned long x;
64
65 p = (unsigned int *) &(fpa11->fpreg[Fn]);
66 get_user(x, &pMem[0]);
67 fpa11->fType[Fn] = (x >> 14) & 0x00000003;
68
69 switch (fpa11->fType[Fn]) {
70 case typeSingle:
71 case typeDouble:
72 {
73 get_user(p[0], &pMem[2]); /* Single */
74 get_user(p[1], &pMem[1]); /* double msw */
75 p[2] = 0; /* empty */
76 }
77 break;
78
79 #ifdef CONFIG_FPE_NWFPE_XP
80 case typeExtended:
81 {
82 get_user(p[1], &pMem[2]);
83 get_user(p[2], &pMem[1]); /* msw */
84 p[0] = (x & 0x80003fff);
85 }
86 break;
87 #endif
88 }
89 }
90
storeSingle(struct roundingData * roundData,const unsigned int Fn,unsigned int __user * pMem)91 static inline void storeSingle(struct roundingData *roundData, const unsigned int Fn, unsigned int __user *pMem)
92 {
93 FPA11 *fpa11 = GET_FPA11();
94 union {
95 float32 f;
96 unsigned int i[1];
97 } val;
98
99 switch (fpa11->fType[Fn]) {
100 case typeDouble:
101 val.f = float64_to_float32(roundData, fpa11->fpreg[Fn].fDouble);
102 break;
103
104 #ifdef CONFIG_FPE_NWFPE_XP
105 case typeExtended:
106 val.f = floatx80_to_float32(roundData, fpa11->fpreg[Fn].fExtended);
107 break;
108 #endif
109
110 default:
111 val.f = fpa11->fpreg[Fn].fSingle;
112 }
113
114 put_user(val.i[0], pMem);
115 }
116
storeDouble(struct roundingData * roundData,const unsigned int Fn,unsigned int __user * pMem)117 static inline void storeDouble(struct roundingData *roundData, const unsigned int Fn, unsigned int __user *pMem)
118 {
119 FPA11 *fpa11 = GET_FPA11();
120 union {
121 float64 f;
122 unsigned int i[2];
123 } val;
124
125 switch (fpa11->fType[Fn]) {
126 case typeSingle:
127 val.f = float32_to_float64(fpa11->fpreg[Fn].fSingle);
128 break;
129
130 #ifdef CONFIG_FPE_NWFPE_XP
131 case typeExtended:
132 val.f = floatx80_to_float64(roundData, fpa11->fpreg[Fn].fExtended);
133 break;
134 #endif
135
136 default:
137 val.f = fpa11->fpreg[Fn].fDouble;
138 }
139
140 #ifdef __ARMEB__
141 put_user(val.i[0], &pMem[0]); /* msw */
142 put_user(val.i[1], &pMem[1]); /* lsw */
143 #else
144 put_user(val.i[1], &pMem[0]); /* msw */
145 put_user(val.i[0], &pMem[1]); /* lsw */
146 #endif
147 }
148
149 #ifdef CONFIG_FPE_NWFPE_XP
storeExtended(const unsigned int Fn,unsigned int __user * pMem)150 static inline void storeExtended(const unsigned int Fn, unsigned int __user *pMem)
151 {
152 FPA11 *fpa11 = GET_FPA11();
153 union {
154 floatx80 f;
155 unsigned int i[3];
156 } val;
157
158 switch (fpa11->fType[Fn]) {
159 case typeSingle:
160 val.f = float32_to_floatx80(fpa11->fpreg[Fn].fSingle);
161 break;
162
163 case typeDouble:
164 val.f = float64_to_floatx80(fpa11->fpreg[Fn].fDouble);
165 break;
166
167 default:
168 val.f = fpa11->fpreg[Fn].fExtended;
169 }
170
171 put_user(val.i[0], &pMem[0]); /* sign & exp */
172 #ifdef __ARMEB__
173 put_user(val.i[1], &pMem[1]); /* msw */
174 put_user(val.i[2], &pMem[2]);
175 #else
176 put_user(val.i[1], &pMem[2]);
177 put_user(val.i[2], &pMem[1]); /* msw */
178 #endif
179 }
180 #endif
181
storeMultiple(const unsigned int Fn,unsigned int __user * pMem)182 static inline void storeMultiple(const unsigned int Fn, unsigned int __user *pMem)
183 {
184 FPA11 *fpa11 = GET_FPA11();
185 register unsigned int nType, *p;
186
187 p = (unsigned int *) &(fpa11->fpreg[Fn]);
188 nType = fpa11->fType[Fn];
189
190 switch (nType) {
191 case typeSingle:
192 case typeDouble:
193 {
194 put_user(p[0], &pMem[2]); /* single */
195 put_user(p[1], &pMem[1]); /* double msw */
196 put_user(nType << 14, &pMem[0]);
197 }
198 break;
199
200 #ifdef CONFIG_FPE_NWFPE_XP
201 case typeExtended:
202 {
203 put_user(p[2], &pMem[1]); /* msw */
204 put_user(p[1], &pMem[2]);
205 put_user((p[0] & 0x80003fff) | (nType << 14), &pMem[0]);
206 }
207 break;
208 #endif
209 }
210 }
211
PerformLDF(const unsigned int opcode)212 unsigned int PerformLDF(const unsigned int opcode)
213 {
214 unsigned int __user *pBase, *pAddress, *pFinal;
215 unsigned int nRc = 1, write_back = WRITE_BACK(opcode);
216
217 pBase = (unsigned int __user *) readRegister(getRn(opcode));
218 if (REG_PC == getRn(opcode)) {
219 pBase += 2;
220 write_back = 0;
221 }
222
223 pFinal = pBase;
224 if (BIT_UP_SET(opcode))
225 pFinal += getOffset(opcode);
226 else
227 pFinal -= getOffset(opcode);
228
229 if (PREINDEXED(opcode))
230 pAddress = pFinal;
231 else
232 pAddress = pBase;
233
234 switch (opcode & MASK_TRANSFER_LENGTH) {
235 case TRANSFER_SINGLE:
236 loadSingle(getFd(opcode), pAddress);
237 break;
238 case TRANSFER_DOUBLE:
239 loadDouble(getFd(opcode), pAddress);
240 break;
241 #ifdef CONFIG_FPE_NWFPE_XP
242 case TRANSFER_EXTENDED:
243 loadExtended(getFd(opcode), pAddress);
244 break;
245 #endif
246 default:
247 nRc = 0;
248 }
249
250 if (write_back)
251 writeRegister(getRn(opcode), (unsigned long) pFinal);
252 return nRc;
253 }
254
PerformSTF(const unsigned int opcode)255 unsigned int PerformSTF(const unsigned int opcode)
256 {
257 unsigned int __user *pBase, *pAddress, *pFinal;
258 unsigned int nRc = 1, write_back = WRITE_BACK(opcode);
259 struct roundingData roundData;
260
261 roundData.mode = SetRoundingMode(opcode);
262 roundData.precision = SetRoundingPrecision(opcode);
263 roundData.exception = 0;
264
265 pBase = (unsigned int __user *) readRegister(getRn(opcode));
266 if (REG_PC == getRn(opcode)) {
267 pBase += 2;
268 write_back = 0;
269 }
270
271 pFinal = pBase;
272 if (BIT_UP_SET(opcode))
273 pFinal += getOffset(opcode);
274 else
275 pFinal -= getOffset(opcode);
276
277 if (PREINDEXED(opcode))
278 pAddress = pFinal;
279 else
280 pAddress = pBase;
281
282 switch (opcode & MASK_TRANSFER_LENGTH) {
283 case TRANSFER_SINGLE:
284 storeSingle(&roundData, getFd(opcode), pAddress);
285 break;
286 case TRANSFER_DOUBLE:
287 storeDouble(&roundData, getFd(opcode), pAddress);
288 break;
289 #ifdef CONFIG_FPE_NWFPE_XP
290 case TRANSFER_EXTENDED:
291 storeExtended(getFd(opcode), pAddress);
292 break;
293 #endif
294 default:
295 nRc = 0;
296 }
297
298 if (roundData.exception)
299 float_raise(roundData.exception);
300
301 if (write_back)
302 writeRegister(getRn(opcode), (unsigned long) pFinal);
303 return nRc;
304 }
305
PerformLFM(const unsigned int opcode)306 unsigned int PerformLFM(const unsigned int opcode)
307 {
308 unsigned int __user *pBase, *pAddress, *pFinal;
309 unsigned int i, Fd, write_back = WRITE_BACK(opcode);
310
311 pBase = (unsigned int __user *) readRegister(getRn(opcode));
312 if (REG_PC == getRn(opcode)) {
313 pBase += 2;
314 write_back = 0;
315 }
316
317 pFinal = pBase;
318 if (BIT_UP_SET(opcode))
319 pFinal += getOffset(opcode);
320 else
321 pFinal -= getOffset(opcode);
322
323 if (PREINDEXED(opcode))
324 pAddress = pFinal;
325 else
326 pAddress = pBase;
327
328 Fd = getFd(opcode);
329 for (i = getRegisterCount(opcode); i > 0; i--) {
330 loadMultiple(Fd, pAddress);
331 pAddress += 3;
332 Fd++;
333 if (Fd == 8)
334 Fd = 0;
335 }
336
337 if (write_back)
338 writeRegister(getRn(opcode), (unsigned long) pFinal);
339 return 1;
340 }
341
PerformSFM(const unsigned int opcode)342 unsigned int PerformSFM(const unsigned int opcode)
343 {
344 unsigned int __user *pBase, *pAddress, *pFinal;
345 unsigned int i, Fd, write_back = WRITE_BACK(opcode);
346
347 pBase = (unsigned int __user *) readRegister(getRn(opcode));
348 if (REG_PC == getRn(opcode)) {
349 pBase += 2;
350 write_back = 0;
351 }
352
353 pFinal = pBase;
354 if (BIT_UP_SET(opcode))
355 pFinal += getOffset(opcode);
356 else
357 pFinal -= getOffset(opcode);
358
359 if (PREINDEXED(opcode))
360 pAddress = pFinal;
361 else
362 pAddress = pBase;
363
364 Fd = getFd(opcode);
365 for (i = getRegisterCount(opcode); i > 0; i--) {
366 storeMultiple(Fd, pAddress);
367 pAddress += 3;
368 Fd++;
369 if (Fd == 8)
370 Fd = 0;
371 }
372
373 if (write_back)
374 writeRegister(getRn(opcode), (unsigned long) pFinal);
375 return 1;
376 }
377
EmulateCPDT(const unsigned int opcode)378 unsigned int EmulateCPDT(const unsigned int opcode)
379 {
380 unsigned int nRc = 0;
381
382 if (LDF_OP(opcode)) {
383 nRc = PerformLDF(opcode);
384 } else if (LFM_OP(opcode)) {
385 nRc = PerformLFM(opcode);
386 } else if (STF_OP(opcode)) {
387 nRc = PerformSTF(opcode);
388 } else if (SFM_OP(opcode)) {
389 nRc = PerformSFM(opcode);
390 } else {
391 nRc = 0;
392 }
393
394 return nRc;
395 }
396