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Merge branch 'for-3.11' of git://linux-nfs.org/~bfields/linux
[linux-2.6.git] / arch / mips / math-emu / cp1emu.c
blobe773659ccf9f8f607db709109e39b0cacb6f7989
1 /*
2 * cp1emu.c: a MIPS coprocessor 1 (fpu) instruction emulator
3 *
4 * MIPS floating point support
5 * Copyright (C) 1994-2000 Algorithmics Ltd.
6 *
7 * Kevin D. Kissell, kevink@mips.com and Carsten Langgaard, carstenl@mips.com
8 * Copyright (C) 2000 MIPS Technologies, Inc.
9 *
10 * This program is free software; you can distribute it and/or modify it
11 * under the terms of the GNU General Public License (Version 2) as
12 * published by the Free Software Foundation.
13 *
14 * This program is distributed in the hope it will be useful, but WITHOUT
15 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
16 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
17 * for more details.
18 *
19 * You should have received a copy of the GNU General Public License along
20 * with this program; if not, write to the Free Software Foundation, Inc.,
21 * 59 Temple Place - Suite 330, Boston MA 02111-1307, USA.
22 *
23 * A complete emulator for MIPS coprocessor 1 instructions. This is
24 * required for #float(switch) or #float(trap), where it catches all
25 * COP1 instructions via the "CoProcessor Unusable" exception.
26 *
27 * More surprisingly it is also required for #float(ieee), to help out
28 * the hardware fpu at the boundaries of the IEEE-754 representation
29 * (denormalised values, infinities, underflow, etc). It is made
30 * quite nasty because emulation of some non-COP1 instructions is
31 * required, e.g. in branch delay slots.
32 *
33 * Note if you know that you won't have an fpu, then you'll get much
34 * better performance by compiling with -msoft-float!
35 */
36 #include <linux/sched.h>
37 #include <linux/module.h>
38 #include <linux/debugfs.h>
39 #include <linux/perf_event.h>
40
41 #include <asm/inst.h>
42 #include <asm/bootinfo.h>
43 #include <asm/processor.h>
44 #include <asm/ptrace.h>
45 #include <asm/signal.h>
46 #include <asm/mipsregs.h>
47 #include <asm/fpu_emulator.h>
48 #include <asm/fpu.h>
49 #include <asm/uaccess.h>
50 #include <asm/branch.h>
51
52 #include "ieee754.h"
53
54 /* Strap kernel emulator for full MIPS IV emulation */
55
56 #ifdef __mips
57 #undef __mips
58 #endif
59 #define __mips 4
60
61 /* Function which emulates a floating point instruction. */
62
63 static int fpu_emu(struct pt_regs *, struct mips_fpu_struct *,
64 mips_instruction);
65
66 #if __mips >= 4 && __mips != 32
67 static int fpux_emu(struct pt_regs *,
68 struct mips_fpu_struct *, mips_instruction, void *__user *);
69 #endif
70
71 /* Further private data for which no space exists in mips_fpu_struct */
72
73 #ifdef CONFIG_DEBUG_FS
74 DEFINE_PER_CPU(struct mips_fpu_emulator_stats, fpuemustats);
75 #endif
76
77 /* Control registers */
78
79 #define FPCREG_RID 0 /* $0 = revision id */
80 #define FPCREG_CSR 31 /* $31 = csr */
81
82 /* Determine rounding mode from the RM bits of the FCSR */
83 #define modeindex(v) ((v) & FPU_CSR_RM)
84
85 /* microMIPS bitfields */
86 #define MM_POOL32A_MINOR_MASK 0x3f
87 #define MM_POOL32A_MINOR_SHIFT 0x6
88 #define MM_MIPS32_COND_FC 0x30
89
90 /* Convert Mips rounding mode (0..3) to IEEE library modes. */
91 static const unsigned char ieee_rm[4] = {
92 [FPU_CSR_RN] = IEEE754_RN,
93 [FPU_CSR_RZ] = IEEE754_RZ,
94 [FPU_CSR_RU] = IEEE754_RU,
95 [FPU_CSR_RD] = IEEE754_RD,
96 };
97 /* Convert IEEE library modes to Mips rounding mode (0..3). */
98 static const unsigned char mips_rm[4] = {
99 [IEEE754_RN] = FPU_CSR_RN,
100 [IEEE754_RZ] = FPU_CSR_RZ,
101 [IEEE754_RD] = FPU_CSR_RD,
102 [IEEE754_RU] = FPU_CSR_RU,
103 };
104
105 #if __mips >= 4
106 /* convert condition code register number to csr bit */
107 static const unsigned int fpucondbit[8] = {
108 FPU_CSR_COND0,
109 FPU_CSR_COND1,
110 FPU_CSR_COND2,
111 FPU_CSR_COND3,
112 FPU_CSR_COND4,
113 FPU_CSR_COND5,
114 FPU_CSR_COND6,
115 FPU_CSR_COND7
116 };
117 #endif
118
119 /* (microMIPS) Convert 16-bit register encoding to 32-bit register encoding. */
120 static const unsigned int reg16to32map[8] = {16, 17, 2, 3, 4, 5, 6, 7};
121
122 /* (microMIPS) Convert certain microMIPS instructions to MIPS32 format. */
123 static const int sd_format[] = {16, 17, 0, 0, 0, 0, 0, 0};
124 static const int sdps_format[] = {16, 17, 22, 0, 0, 0, 0, 0};
125 static const int dwl_format[] = {17, 20, 21, 0, 0, 0, 0, 0};
126 static const int swl_format[] = {16, 20, 21, 0, 0, 0, 0, 0};
127
128 /*
129 * This functions translates a 32-bit microMIPS instruction
130 * into a 32-bit MIPS32 instruction. Returns 0 on success
131 * and SIGILL otherwise.
132 */
133 static int microMIPS32_to_MIPS32(union mips_instruction *insn_ptr)
134 {
135 union mips_instruction insn = *insn_ptr;
136 union mips_instruction mips32_insn = insn;
137 int func, fmt, op;
138
139 switch (insn.mm_i_format.opcode) {
140 case mm_ldc132_op:
141 mips32_insn.mm_i_format.opcode = ldc1_op;
142 mips32_insn.mm_i_format.rt = insn.mm_i_format.rs;
143 mips32_insn.mm_i_format.rs = insn.mm_i_format.rt;
144 break;
145 case mm_lwc132_op:
146 mips32_insn.mm_i_format.opcode = lwc1_op;
147 mips32_insn.mm_i_format.rt = insn.mm_i_format.rs;
148 mips32_insn.mm_i_format.rs = insn.mm_i_format.rt;
149 break;
150 case mm_sdc132_op:
151 mips32_insn.mm_i_format.opcode = sdc1_op;
152 mips32_insn.mm_i_format.rt = insn.mm_i_format.rs;
153 mips32_insn.mm_i_format.rs = insn.mm_i_format.rt;
154 break;
155 case mm_swc132_op:
156 mips32_insn.mm_i_format.opcode = swc1_op;
157 mips32_insn.mm_i_format.rt = insn.mm_i_format.rs;
158 mips32_insn.mm_i_format.rs = insn.mm_i_format.rt;
159 break;
160 case mm_pool32i_op:
161 /* NOTE: offset is << by 1 if in microMIPS mode. */
162 if ((insn.mm_i_format.rt == mm_bc1f_op) ||
163 (insn.mm_i_format.rt == mm_bc1t_op)) {
164 mips32_insn.fb_format.opcode = cop1_op;
165 mips32_insn.fb_format.bc = bc_op;
166 mips32_insn.fb_format.flag =
167 (insn.mm_i_format.rt == mm_bc1t_op) ? 1 : 0;
168 } else
169 return SIGILL;
170 break;
171 case mm_pool32f_op:
172 switch (insn.mm_fp0_format.func) {
173 case mm_32f_01_op:
174 case mm_32f_11_op:
175 case mm_32f_02_op:
176 case mm_32f_12_op:
177 case mm_32f_41_op:
178 case mm_32f_51_op:
179 case mm_32f_42_op:
180 case mm_32f_52_op:
181 op = insn.mm_fp0_format.func;
182 if (op == mm_32f_01_op)
183 func = madd_s_op;
184 else if (op == mm_32f_11_op)
185 func = madd_d_op;
186 else if (op == mm_32f_02_op)
187 func = nmadd_s_op;
188 else if (op == mm_32f_12_op)
189 func = nmadd_d_op;
190 else if (op == mm_32f_41_op)
191 func = msub_s_op;
192 else if (op == mm_32f_51_op)
193 func = msub_d_op;
194 else if (op == mm_32f_42_op)
195 func = nmsub_s_op;
196 else
197 func = nmsub_d_op;
198 mips32_insn.fp6_format.opcode = cop1x_op;
199 mips32_insn.fp6_format.fr = insn.mm_fp6_format.fr;
200 mips32_insn.fp6_format.ft = insn.mm_fp6_format.ft;
201 mips32_insn.fp6_format.fs = insn.mm_fp6_format.fs;
202 mips32_insn.fp6_format.fd = insn.mm_fp6_format.fd;
203 mips32_insn.fp6_format.func = func;
204 break;
205 case mm_32f_10_op:
206 func = -1; /* Invalid */
207 op = insn.mm_fp5_format.op & 0x7;
208 if (op == mm_ldxc1_op)
209 func = ldxc1_op;
210 else if (op == mm_sdxc1_op)
211 func = sdxc1_op;
212 else if (op == mm_lwxc1_op)
213 func = lwxc1_op;
214 else if (op == mm_swxc1_op)
215 func = swxc1_op;
216
217 if (func != -1) {
218 mips32_insn.r_format.opcode = cop1x_op;
219 mips32_insn.r_format.rs =
220 insn.mm_fp5_format.base;
221 mips32_insn.r_format.rt =
222 insn.mm_fp5_format.index;
223 mips32_insn.r_format.rd = 0;
224 mips32_insn.r_format.re = insn.mm_fp5_format.fd;
225 mips32_insn.r_format.func = func;
226 } else
227 return SIGILL;
228 break;
229 case mm_32f_40_op:
230 op = -1; /* Invalid */
231 if (insn.mm_fp2_format.op == mm_fmovt_op)
232 op = 1;
233 else if (insn.mm_fp2_format.op == mm_fmovf_op)
234 op = 0;
235 if (op != -1) {
236 mips32_insn.fp0_format.opcode = cop1_op;
237 mips32_insn.fp0_format.fmt =
238 sdps_format[insn.mm_fp2_format.fmt];
239 mips32_insn.fp0_format.ft =
240 (insn.mm_fp2_format.cc<<2) + op;
241 mips32_insn.fp0_format.fs =
242 insn.mm_fp2_format.fs;
243 mips32_insn.fp0_format.fd =
244 insn.mm_fp2_format.fd;
245 mips32_insn.fp0_format.func = fmovc_op;
246 } else
247 return SIGILL;
248 break;
249 case mm_32f_60_op:
250 func = -1; /* Invalid */
251 if (insn.mm_fp0_format.op == mm_fadd_op)
252 func = fadd_op;
253 else if (insn.mm_fp0_format.op == mm_fsub_op)
254 func = fsub_op;
255 else if (insn.mm_fp0_format.op == mm_fmul_op)
256 func = fmul_op;
257 else if (insn.mm_fp0_format.op == mm_fdiv_op)
258 func = fdiv_op;
259 if (func != -1) {
260 mips32_insn.fp0_format.opcode = cop1_op;
261 mips32_insn.fp0_format.fmt =
262 sdps_format[insn.mm_fp0_format.fmt];
263 mips32_insn.fp0_format.ft =
264 insn.mm_fp0_format.ft;
265 mips32_insn.fp0_format.fs =
266 insn.mm_fp0_format.fs;
267 mips32_insn.fp0_format.fd =
268 insn.mm_fp0_format.fd;
269 mips32_insn.fp0_format.func = func;
270 } else
271 return SIGILL;
272 break;
273 case mm_32f_70_op:
274 func = -1; /* Invalid */
275 if (insn.mm_fp0_format.op == mm_fmovn_op)
276 func = fmovn_op;
277 else if (insn.mm_fp0_format.op == mm_fmovz_op)
278 func = fmovz_op;
279 if (func != -1) {
280 mips32_insn.fp0_format.opcode = cop1_op;
281 mips32_insn.fp0_format.fmt =
282 sdps_format[insn.mm_fp0_format.fmt];
283 mips32_insn.fp0_format.ft =
284 insn.mm_fp0_format.ft;
285 mips32_insn.fp0_format.fs =
286 insn.mm_fp0_format.fs;
287 mips32_insn.fp0_format.fd =
288 insn.mm_fp0_format.fd;
289 mips32_insn.fp0_format.func = func;
290 } else
291 return SIGILL;
292 break;
293 case mm_32f_73_op: /* POOL32FXF */
294 switch (insn.mm_fp1_format.op) {
295 case mm_movf0_op:
296 case mm_movf1_op:
297 case mm_movt0_op:
298 case mm_movt1_op:
299 if ((insn.mm_fp1_format.op & 0x7f) ==
300 mm_movf0_op)
301 op = 0;
302 else
303 op = 1;
304 mips32_insn.r_format.opcode = spec_op;
305 mips32_insn.r_format.rs = insn.mm_fp4_format.fs;
306 mips32_insn.r_format.rt =
307 (insn.mm_fp4_format.cc << 2) + op;
308 mips32_insn.r_format.rd = insn.mm_fp4_format.rt;
309 mips32_insn.r_format.re = 0;
310 mips32_insn.r_format.func = movc_op;
311 break;
312 case mm_fcvtd0_op:
313 case mm_fcvtd1_op:
314 case mm_fcvts0_op:
315 case mm_fcvts1_op:
316 if ((insn.mm_fp1_format.op & 0x7f) ==
317 mm_fcvtd0_op) {
318 func = fcvtd_op;
319 fmt = swl_format[insn.mm_fp3_format.fmt];
320 } else {
321 func = fcvts_op;
322 fmt = dwl_format[insn.mm_fp3_format.fmt];
323 }
324 mips32_insn.fp0_format.opcode = cop1_op;
325 mips32_insn.fp0_format.fmt = fmt;
326 mips32_insn.fp0_format.ft = 0;
327 mips32_insn.fp0_format.fs =
328 insn.mm_fp3_format.fs;
329 mips32_insn.fp0_format.fd =
330 insn.mm_fp3_format.rt;
331 mips32_insn.fp0_format.func = func;
332 break;
333 case mm_fmov0_op:
334 case mm_fmov1_op:
335 case mm_fabs0_op:
336 case mm_fabs1_op:
337 case mm_fneg0_op:
338 case mm_fneg1_op:
339 if ((insn.mm_fp1_format.op & 0x7f) ==
340 mm_fmov0_op)
341 func = fmov_op;
342 else if ((insn.mm_fp1_format.op & 0x7f) ==
343 mm_fabs0_op)
344 func = fabs_op;
345 else
346 func = fneg_op;
347 mips32_insn.fp0_format.opcode = cop1_op;
348 mips32_insn.fp0_format.fmt =
349 sdps_format[insn.mm_fp3_format.fmt];
350 mips32_insn.fp0_format.ft = 0;
351 mips32_insn.fp0_format.fs =
352 insn.mm_fp3_format.fs;
353 mips32_insn.fp0_format.fd =
354 insn.mm_fp3_format.rt;
355 mips32_insn.fp0_format.func = func;
356 break;
357 case mm_ffloorl_op:
358 case mm_ffloorw_op:
359 case mm_fceill_op:
360 case mm_fceilw_op:
361 case mm_ftruncl_op:
362 case mm_ftruncw_op:
363 case mm_froundl_op:
364 case mm_froundw_op:
365 case mm_fcvtl_op:
366 case mm_fcvtw_op:
367 if (insn.mm_fp1_format.op == mm_ffloorl_op)
368 func = ffloorl_op;
369 else if (insn.mm_fp1_format.op == mm_ffloorw_op)
370 func = ffloor_op;
371 else if (insn.mm_fp1_format.op == mm_fceill_op)
372 func = fceill_op;
373 else if (insn.mm_fp1_format.op == mm_fceilw_op)
374 func = fceil_op;
375 else if (insn.mm_fp1_format.op == mm_ftruncl_op)
376 func = ftruncl_op;
377 else if (insn.mm_fp1_format.op == mm_ftruncw_op)
378 func = ftrunc_op;
379 else if (insn.mm_fp1_format.op == mm_froundl_op)
380 func = froundl_op;
381 else if (insn.mm_fp1_format.op == mm_froundw_op)
382 func = fround_op;
383 else if (insn.mm_fp1_format.op == mm_fcvtl_op)
384 func = fcvtl_op;
385 else
386 func = fcvtw_op;
387 mips32_insn.fp0_format.opcode = cop1_op;
388 mips32_insn.fp0_format.fmt =
389 sd_format[insn.mm_fp1_format.fmt];
390 mips32_insn.fp0_format.ft = 0;
391 mips32_insn.fp0_format.fs =
392 insn.mm_fp1_format.fs;
393 mips32_insn.fp0_format.fd =
394 insn.mm_fp1_format.rt;
395 mips32_insn.fp0_format.func = func;
396 break;
397 case mm_frsqrt_op:
398 case mm_fsqrt_op:
399 case mm_frecip_op:
400 if (insn.mm_fp1_format.op == mm_frsqrt_op)
401 func = frsqrt_op;
402 else if (insn.mm_fp1_format.op == mm_fsqrt_op)
403 func = fsqrt_op;
404 else
405 func = frecip_op;
406 mips32_insn.fp0_format.opcode = cop1_op;
407 mips32_insn.fp0_format.fmt =
408 sdps_format[insn.mm_fp1_format.fmt];
409 mips32_insn.fp0_format.ft = 0;
410 mips32_insn.fp0_format.fs =
411 insn.mm_fp1_format.fs;
412 mips32_insn.fp0_format.fd =
413 insn.mm_fp1_format.rt;
414 mips32_insn.fp0_format.func = func;
415 break;
416 case mm_mfc1_op:
417 case mm_mtc1_op:
418 case mm_cfc1_op:
419 case mm_ctc1_op:
420 if (insn.mm_fp1_format.op == mm_mfc1_op)
421 op = mfc_op;
422 else if (insn.mm_fp1_format.op == mm_mtc1_op)
423 op = mtc_op;
424 else if (insn.mm_fp1_format.op == mm_cfc1_op)
425 op = cfc_op;
426 else
427 op = ctc_op;
428 mips32_insn.fp1_format.opcode = cop1_op;
429 mips32_insn.fp1_format.op = op;
430 mips32_insn.fp1_format.rt =
431 insn.mm_fp1_format.rt;
432 mips32_insn.fp1_format.fs =
433 insn.mm_fp1_format.fs;
434 mips32_insn.fp1_format.fd = 0;
435 mips32_insn.fp1_format.func = 0;
436 break;
437 default:
438 return SIGILL;
439 break;
440 }
441 break;
442 case mm_32f_74_op: /* c.cond.fmt */
443 mips32_insn.fp0_format.opcode = cop1_op;
444 mips32_insn.fp0_format.fmt =
445 sdps_format[insn.mm_fp4_format.fmt];
446 mips32_insn.fp0_format.ft = insn.mm_fp4_format.rt;
447 mips32_insn.fp0_format.fs = insn.mm_fp4_format.fs;
448 mips32_insn.fp0_format.fd = insn.mm_fp4_format.cc << 2;
449 mips32_insn.fp0_format.func =
450 insn.mm_fp4_format.cond | MM_MIPS32_COND_FC;
451 break;
452 default:
453 return SIGILL;
454 break;
455 }
456 break;
457 default:
458 return SIGILL;
459 break;
460 }
461
462 *insn_ptr = mips32_insn;
463 return 0;
464 }
465
466 int mm_isBranchInstr(struct pt_regs *regs, struct mm_decoded_insn dec_insn,
467 unsigned long *contpc)
468 {
469 union mips_instruction insn = (union mips_instruction)dec_insn.insn;
470 int bc_false = 0;
471 unsigned int fcr31;
472 unsigned int bit;
473
474 if (!cpu_has_mmips)
475 return 0;
476
477 switch (insn.mm_i_format.opcode) {
478 case mm_pool32a_op:
479 if ((insn.mm_i_format.simmediate & MM_POOL32A_MINOR_MASK) ==
480 mm_pool32axf_op) {
481 switch (insn.mm_i_format.simmediate >>
482 MM_POOL32A_MINOR_SHIFT) {
483 case mm_jalr_op:
484 case mm_jalrhb_op:
485 case mm_jalrs_op:
486 case mm_jalrshb_op:
487 if (insn.mm_i_format.rt != 0) /* Not mm_jr */
488 regs->regs[insn.mm_i_format.rt] =
489 regs->cp0_epc +
490 dec_insn.pc_inc +
491 dec_insn.next_pc_inc;
492 *contpc = regs->regs[insn.mm_i_format.rs];
493 return 1;
494 break;
495 }
496 }
497 break;
498 case mm_pool32i_op:
499 switch (insn.mm_i_format.rt) {
500 case mm_bltzals_op:
501 case mm_bltzal_op:
502 regs->regs[31] = regs->cp0_epc +
503 dec_insn.pc_inc +
504 dec_insn.next_pc_inc;
505 /* Fall through */
506 case mm_bltz_op:
507 if ((long)regs->regs[insn.mm_i_format.rs] < 0)
508 *contpc = regs->cp0_epc +
509 dec_insn.pc_inc +
510 (insn.mm_i_format.simmediate << 1);
511 else
512 *contpc = regs->cp0_epc +
513 dec_insn.pc_inc +
514 dec_insn.next_pc_inc;
515 return 1;
516 break;
517 case mm_bgezals_op:
518 case mm_bgezal_op:
519 regs->regs[31] = regs->cp0_epc +
520 dec_insn.pc_inc +
521 dec_insn.next_pc_inc;
522 /* Fall through */
523 case mm_bgez_op:
524 if ((long)regs->regs[insn.mm_i_format.rs] >= 0)
525 *contpc = regs->cp0_epc +
526 dec_insn.pc_inc +
527 (insn.mm_i_format.simmediate << 1);
528 else
529 *contpc = regs->cp0_epc +
530 dec_insn.pc_inc +
531 dec_insn.next_pc_inc;
532 return 1;
533 break;
534 case mm_blez_op:
535 if ((long)regs->regs[insn.mm_i_format.rs] <= 0)
536 *contpc = regs->cp0_epc +
537 dec_insn.pc_inc +
538 (insn.mm_i_format.simmediate << 1);
539 else
540 *contpc = regs->cp0_epc +
541 dec_insn.pc_inc +
542 dec_insn.next_pc_inc;
543 return 1;
544 break;
545 case mm_bgtz_op:
546 if ((long)regs->regs[insn.mm_i_format.rs] <= 0)
547 *contpc = regs->cp0_epc +
548 dec_insn.pc_inc +
549 (insn.mm_i_format.simmediate << 1);
550 else
551 *contpc = regs->cp0_epc +
552 dec_insn.pc_inc +
553 dec_insn.next_pc_inc;
554 return 1;
555 break;
556 case mm_bc2f_op:
557 case mm_bc1f_op:
558 bc_false = 1;
559 /* Fall through */
560 case mm_bc2t_op:
561 case mm_bc1t_op:
562 preempt_disable();
563 if (is_fpu_owner())
564 asm volatile("cfc1\t%0,$31" : "=r" (fcr31));
565 else
566 fcr31 = current->thread.fpu.fcr31;
567 preempt_enable();
568
569 if (bc_false)
570 fcr31 = ~fcr31;
571
572 bit = (insn.mm_i_format.rs >> 2);
573 bit += (bit != 0);
574 bit += 23;
575 if (fcr31 & (1 << bit))
576 *contpc = regs->cp0_epc +
577 dec_insn.pc_inc +
578 (insn.mm_i_format.simmediate << 1);
579 else
580 *contpc = regs->cp0_epc +
581 dec_insn.pc_inc + dec_insn.next_pc_inc;
582 return 1;
583 break;
584 }
585 break;
586 case mm_pool16c_op:
587 switch (insn.mm_i_format.rt) {
588 case mm_jalr16_op:
589 case mm_jalrs16_op:
590 regs->regs[31] = regs->cp0_epc +
591 dec_insn.pc_inc + dec_insn.next_pc_inc;
592 /* Fall through */
593 case mm_jr16_op:
594 *contpc = regs->regs[insn.mm_i_format.rs];
595 return 1;
596 break;
597 }
598 break;
599 case mm_beqz16_op:
600 if ((long)regs->regs[reg16to32map[insn.mm_b1_format.rs]] == 0)
601 *contpc = regs->cp0_epc +
602 dec_insn.pc_inc +
603 (insn.mm_b1_format.simmediate << 1);
604 else
605 *contpc = regs->cp0_epc +
606 dec_insn.pc_inc + dec_insn.next_pc_inc;
607 return 1;
608 break;
609 case mm_bnez16_op:
610 if ((long)regs->regs[reg16to32map[insn.mm_b1_format.rs]] != 0)
611 *contpc = regs->cp0_epc +
612 dec_insn.pc_inc +
613 (insn.mm_b1_format.simmediate << 1);
614 else
615 *contpc = regs->cp0_epc +
616 dec_insn.pc_inc + dec_insn.next_pc_inc;
617 return 1;
618 break;
619 case mm_b16_op:
620 *contpc = regs->cp0_epc + dec_insn.pc_inc +
621 (insn.mm_b0_format.simmediate << 1);
622 return 1;
623 break;
624 case mm_beq32_op:
625 if (regs->regs[insn.mm_i_format.rs] ==
626 regs->regs[insn.mm_i_format.rt])
627 *contpc = regs->cp0_epc +
628 dec_insn.pc_inc +
629 (insn.mm_i_format.simmediate << 1);
630 else
631 *contpc = regs->cp0_epc +
632 dec_insn.pc_inc +
633 dec_insn.next_pc_inc;
634 return 1;
635 break;
636 case mm_bne32_op:
637 if (regs->regs[insn.mm_i_format.rs] !=
638 regs->regs[insn.mm_i_format.rt])
639 *contpc = regs->cp0_epc +
640 dec_insn.pc_inc +
641 (insn.mm_i_format.simmediate << 1);
642 else
643 *contpc = regs->cp0_epc +
644 dec_insn.pc_inc + dec_insn.next_pc_inc;
645 return 1;
646 break;
647 case mm_jalx32_op:
648 regs->regs[31] = regs->cp0_epc +
649 dec_insn.pc_inc + dec_insn.next_pc_inc;
650 *contpc = regs->cp0_epc + dec_insn.pc_inc;
651 *contpc >>= 28;
652 *contpc <<= 28;
653 *contpc |= (insn.j_format.target << 2);
654 return 1;
655 break;
656 case mm_jals32_op:
657 case mm_jal32_op:
658 regs->regs[31] = regs->cp0_epc +
659 dec_insn.pc_inc + dec_insn.next_pc_inc;
660 /* Fall through */
661 case mm_j32_op:
662 *contpc = regs->cp0_epc + dec_insn.pc_inc;
663 *contpc >>= 27;
664 *contpc <<= 27;
665 *contpc |= (insn.j_format.target << 1);
666 set_isa16_mode(*contpc);
667 return 1;
668 break;
669 }
670 return 0;
671 }
672
673 /*
674 * Redundant with logic already in kernel/branch.c,
675 * embedded in compute_return_epc. At some point,
676 * a single subroutine should be used across both
677 * modules.
678 */
679 static int isBranchInstr(struct pt_regs *regs, struct mm_decoded_insn dec_insn,
680 unsigned long *contpc)
681 {
682 union mips_instruction insn = (union mips_instruction)dec_insn.insn;
683 unsigned int fcr31;
684 unsigned int bit = 0;
685
686 switch (insn.i_format.opcode) {
687 case spec_op:
688 switch (insn.r_format.func) {
689 case jalr_op:
690 regs->regs[insn.r_format.rd] =
691 regs->cp0_epc + dec_insn.pc_inc +
692 dec_insn.next_pc_inc;
693 /* Fall through */
694 case jr_op:
695 *contpc = regs->regs[insn.r_format.rs];
696 return 1;
697 break;
698 }
699 break;
700 case bcond_op:
701 switch (insn.i_format.rt) {
702 case bltzal_op:
703 case bltzall_op:
704 regs->regs[31] = regs->cp0_epc +
705 dec_insn.pc_inc +
706 dec_insn.next_pc_inc;
707 /* Fall through */
708 case bltz_op:
709 case bltzl_op:
710 if ((long)regs->regs[insn.i_format.rs] < 0)
711 *contpc = regs->cp0_epc +
712 dec_insn.pc_inc +
713 (insn.i_format.simmediate << 2);
714 else
715 *contpc = regs->cp0_epc +
716 dec_insn.pc_inc +
717 dec_insn.next_pc_inc;
718 return 1;
719 break;
720 case bgezal_op:
721 case bgezall_op:
722 regs->regs[31] = regs->cp0_epc +
723 dec_insn.pc_inc +
724 dec_insn.next_pc_inc;
725 /* Fall through */
726 case bgez_op:
727 case bgezl_op:
728 if ((long)regs->regs[insn.i_format.rs] >= 0)
729 *contpc = regs->cp0_epc +
730 dec_insn.pc_inc +
731 (insn.i_format.simmediate << 2);
732 else
733 *contpc = regs->cp0_epc +
734 dec_insn.pc_inc +
735 dec_insn.next_pc_inc;
736 return 1;
737 break;
738 }
739 break;
740 case jalx_op:
741 set_isa16_mode(bit);
742 case jal_op:
743 regs->regs[31] = regs->cp0_epc +
744 dec_insn.pc_inc +
745 dec_insn.next_pc_inc;
746 /* Fall through */
747 case j_op:
748 *contpc = regs->cp0_epc + dec_insn.pc_inc;
749 *contpc >>= 28;
750 *contpc <<= 28;
751 *contpc |= (insn.j_format.target << 2);
752 /* Set microMIPS mode bit: XOR for jalx. */
753 *contpc ^= bit;
754 return 1;
755 break;
756 case beq_op:
757 case beql_op:
758 if (regs->regs[insn.i_format.rs] ==
759 regs->regs[insn.i_format.rt])
760 *contpc = regs->cp0_epc +
761 dec_insn.pc_inc +
762 (insn.i_format.simmediate << 2);
763 else
764 *contpc = regs->cp0_epc +
765 dec_insn.pc_inc +
766 dec_insn.next_pc_inc;
767 return 1;
768 break;
769 case bne_op:
770 case bnel_op:
771 if (regs->regs[insn.i_format.rs] !=
772 regs->regs[insn.i_format.rt])
773 *contpc = regs->cp0_epc +
774 dec_insn.pc_inc +
775 (insn.i_format.simmediate << 2);
776 else
777 *contpc = regs->cp0_epc +
778 dec_insn.pc_inc +
779 dec_insn.next_pc_inc;
780 return 1;
781 break;
782 case blez_op:
783 case blezl_op:
784 if ((long)regs->regs[insn.i_format.rs] <= 0)
785 *contpc = regs->cp0_epc +
786 dec_insn.pc_inc +
787 (insn.i_format.simmediate << 2);
788 else
789 *contpc = regs->cp0_epc +
790 dec_insn.pc_inc +
791 dec_insn.next_pc_inc;
792 return 1;
793 break;
794 case bgtz_op:
795 case bgtzl_op:
796 if ((long)regs->regs[insn.i_format.rs] > 0)
797 *contpc = regs->cp0_epc +
798 dec_insn.pc_inc +
799 (insn.i_format.simmediate << 2);
800 else
801 *contpc = regs->cp0_epc +
802 dec_insn.pc_inc +
803 dec_insn.next_pc_inc;
804 return 1;
805 break;
806 case cop0_op:
807 case cop1_op:
808 case cop2_op:
809 case cop1x_op:
810 if (insn.i_format.rs == bc_op) {
811 preempt_disable();
812 if (is_fpu_owner())
813 asm volatile("cfc1\t%0,$31" : "=r" (fcr31));
814 else
815 fcr31 = current->thread.fpu.fcr31;
816 preempt_enable();
817
818 bit = (insn.i_format.rt >> 2);
819 bit += (bit != 0);
820 bit += 23;
821 switch (insn.i_format.rt & 3) {
822 case 0: /* bc1f */
823 case 2: /* bc1fl */
824 if (~fcr31 & (1 << bit))
825 *contpc = regs->cp0_epc +
826 dec_insn.pc_inc +
827 (insn.i_format.simmediate << 2);
828 else
829 *contpc = regs->cp0_epc +
830 dec_insn.pc_inc +
831 dec_insn.next_pc_inc;
832 return 1;
833 break;
834 case 1: /* bc1t */
835 case 3: /* bc1tl */
836 if (fcr31 & (1 << bit))
837 *contpc = regs->cp0_epc +
838 dec_insn.pc_inc +
839 (insn.i_format.simmediate << 2);
840 else
841 *contpc = regs->cp0_epc +
842 dec_insn.pc_inc +
843 dec_insn.next_pc_inc;
844 return 1;
845 break;
846 }
847 }
848 break;
849 }
850 return 0;
851 }
852
853 /*
854 * In the Linux kernel, we support selection of FPR format on the
855 * basis of the Status.FR bit. If an FPU is not present, the FR bit
856 * is hardwired to zero, which would imply a 32-bit FPU even for
857 * 64-bit CPUs so we rather look at TIF_32BIT_REGS.
858 * FPU emu is slow and bulky and optimizing this function offers fairly
859 * sizeable benefits so we try to be clever and make this function return
860 * a constant whenever possible, that is on 64-bit kernels without O32
861 * compatibility enabled and on 32-bit kernels.
862 */
863 static inline int cop1_64bit(struct pt_regs *xcp)
864 {
865 #if defined(CONFIG_64BIT) && !defined(CONFIG_MIPS32_O32)
866 return 1;
867 #elif defined(CONFIG_64BIT) && defined(CONFIG_MIPS32_O32)
868 return !test_thread_flag(TIF_32BIT_REGS);
869 #else
870 return 0;
871 #endif
872 }
873
874 #define SIFROMREG(si, x) ((si) = cop1_64bit(xcp) || !(x & 1) ? \
875 (int)ctx->fpr[x] : (int)(ctx->fpr[x & ~1] >> 32))
876
877 #define SITOREG(si, x) (ctx->fpr[x & ~(cop1_64bit(xcp) == 0)] = \
878 cop1_64bit(xcp) || !(x & 1) ? \
879 ctx->fpr[x & ~1] >> 32 << 32 | (u32)(si) : \
880 ctx->fpr[x & ~1] << 32 >> 32 | (u64)(si) << 32)
881
882 #define DIFROMREG(di, x) ((di) = ctx->fpr[x & ~(cop1_64bit(xcp) == 0)])
883 #define DITOREG(di, x) (ctx->fpr[x & ~(cop1_64bit(xcp) == 0)] = (di))
884
885 #define SPFROMREG(sp, x) SIFROMREG((sp).bits, x)
886 #define SPTOREG(sp, x) SITOREG((sp).bits, x)
887 #define DPFROMREG(dp, x) DIFROMREG((dp).bits, x)
888 #define DPTOREG(dp, x) DITOREG((dp).bits, x)
889
890 /*
891 * Emulate the single floating point instruction pointed at by EPC.
892 * Two instructions if the instruction is in a branch delay slot.
893 */
894
895 static int cop1Emulate(struct pt_regs *xcp, struct mips_fpu_struct *ctx,
896 struct mm_decoded_insn dec_insn, void *__user *fault_addr)
897 {
898 mips_instruction ir;
899 unsigned long contpc = xcp->cp0_epc + dec_insn.pc_inc;
900 unsigned int cond;
901 int pc_inc;
902
903 /* XXX NEC Vr54xx bug workaround */
904 if (xcp->cp0_cause & CAUSEF_BD) {
905 if (dec_insn.micro_mips_mode) {
906 if (!mm_isBranchInstr(xcp, dec_insn, &contpc))
907 xcp->cp0_cause &= ~CAUSEF_BD;
908 } else {
909 if (!isBranchInstr(xcp, dec_insn, &contpc))
910 xcp->cp0_cause &= ~CAUSEF_BD;
911 }
912 }
913
914 if (xcp->cp0_cause & CAUSEF_BD) {
915 /*
916 * The instruction to be emulated is in a branch delay slot
917 * which means that we have to emulate the branch instruction
918 * BEFORE we do the cop1 instruction.
919 *
920 * This branch could be a COP1 branch, but in that case we
921 * would have had a trap for that instruction, and would not
922 * come through this route.
923 *
924 * Linux MIPS branch emulator operates on context, updating the
925 * cp0_epc.
926 */
927 ir = dec_insn.next_insn; /* process delay slot instr */
928 pc_inc = dec_insn.next_pc_inc;
929 } else {
930 ir = dec_insn.insn; /* process current instr */
931 pc_inc = dec_insn.pc_inc;
932 }
933
934 /*
935 * Since microMIPS FPU instructios are a subset of MIPS32 FPU
936 * instructions, we want to convert microMIPS FPU instructions
937 * into MIPS32 instructions so that we could reuse all of the
938 * FPU emulation code.
939 *
940 * NOTE: We cannot do this for branch instructions since they
941 * are not a subset. Example: Cannot emulate a 16-bit
942 * aligned target address with a MIPS32 instruction.
943 */
944 if (dec_insn.micro_mips_mode) {
945 /*
946 * If next instruction is a 16-bit instruction, then it
947 * it cannot be a FPU instruction. This could happen
948 * since we can be called for non-FPU instructions.
949 */
950 if ((pc_inc == 2) ||
951 (microMIPS32_to_MIPS32((union mips_instruction *)&ir)
952 == SIGILL))
953 return SIGILL;
954 }
955
956 emul:
957 perf_sw_event(PERF_COUNT_SW_EMULATION_FAULTS, 1, xcp, 0);
958 MIPS_FPU_EMU_INC_STATS(emulated);
959 switch (MIPSInst_OPCODE(ir)) {
960 case ldc1_op:{
961 u64 __user *va = (u64 __user *) (xcp->regs[MIPSInst_RS(ir)] +
962 MIPSInst_SIMM(ir));
963 u64 val;
964
965 MIPS_FPU_EMU_INC_STATS(loads);
966
967 if (!access_ok(VERIFY_READ, va, sizeof(u64))) {
968 MIPS_FPU_EMU_INC_STATS(errors);
969 *fault_addr = va;
970 return SIGBUS;
971 }
972 if (__get_user(val, va)) {
973 MIPS_FPU_EMU_INC_STATS(errors);
974 *fault_addr = va;
975 return SIGSEGV;
976 }
977 DITOREG(val, MIPSInst_RT(ir));
978 break;
979 }
980
981 case sdc1_op:{
982 u64 __user *va = (u64 __user *) (xcp->regs[MIPSInst_RS(ir)] +
983 MIPSInst_SIMM(ir));
984 u64 val;
985
986 MIPS_FPU_EMU_INC_STATS(stores);
987 DIFROMREG(val, MIPSInst_RT(ir));
988 if (!access_ok(VERIFY_WRITE, va, sizeof(u64))) {
989 MIPS_FPU_EMU_INC_STATS(errors);
990 *fault_addr = va;
991 return SIGBUS;
992 }
993 if (__put_user(val, va)) {
994 MIPS_FPU_EMU_INC_STATS(errors);
995 *fault_addr = va;
996 return SIGSEGV;
997 }
998 break;
999 }
1000
1001 case lwc1_op:{
1002 u32 __user *va = (u32 __user *) (xcp->regs[MIPSInst_RS(ir)] +
1003 MIPSInst_SIMM(ir));
1004 u32 val;
1005
1006 MIPS_FPU_EMU_INC_STATS(loads);
1007 if (!access_ok(VERIFY_READ, va, sizeof(u32))) {
1008 MIPS_FPU_EMU_INC_STATS(errors);
1009 *fault_addr = va;
1010 return SIGBUS;
1011 }
1012 if (__get_user(val, va)) {
1013 MIPS_FPU_EMU_INC_STATS(errors);
1014 *fault_addr = va;
1015 return SIGSEGV;
1016 }
1017 SITOREG(val, MIPSInst_RT(ir));
1018 break;
1019 }
1020
1021 case swc1_op:{
1022 u32 __user *va = (u32 __user *) (xcp->regs[MIPSInst_RS(ir)] +
1023 MIPSInst_SIMM(ir));
1024 u32 val;
1025
1026 MIPS_FPU_EMU_INC_STATS(stores);
1027 SIFROMREG(val, MIPSInst_RT(ir));
1028 if (!access_ok(VERIFY_WRITE, va, sizeof(u32))) {
1029 MIPS_FPU_EMU_INC_STATS(errors);
1030 *fault_addr = va;
1031 return SIGBUS;
1032 }
1033 if (__put_user(val, va)) {
1034 MIPS_FPU_EMU_INC_STATS(errors);
1035 *fault_addr = va;
1036 return SIGSEGV;
1037 }
1038 break;
1039 }
1040
1041 case cop1_op:
1042 switch (MIPSInst_RS(ir)) {
1043
1044 #if defined(__mips64)
1045 case dmfc_op:
1046 /* copregister fs -> gpr[rt] */
1047 if (MIPSInst_RT(ir) != 0) {
1048 DIFROMREG(xcp->regs[MIPSInst_RT(ir)],
1049 MIPSInst_RD(ir));
1050 }
1051 break;
1052
1053 case dmtc_op:
1054 /* copregister fs <- rt */
1055 DITOREG(xcp->regs[MIPSInst_RT(ir)], MIPSInst_RD(ir));
1056 break;
1057 #endif
1058
1059 case mfc_op:
1060 /* copregister rd -> gpr[rt] */
1061 if (MIPSInst_RT(ir) != 0) {
1062 SIFROMREG(xcp->regs[MIPSInst_RT(ir)],
1063 MIPSInst_RD(ir));
1064 }
1065 break;
1066
1067 case mtc_op:
1068 /* copregister rd <- rt */
1069 SITOREG(xcp->regs[MIPSInst_RT(ir)], MIPSInst_RD(ir));
1070 break;
1071
1072 case cfc_op:{
1073 /* cop control register rd -> gpr[rt] */
1074 u32 value;
1075
1076 if (MIPSInst_RD(ir) == FPCREG_CSR) {
1077 value = ctx->fcr31;
1078 value = (value & ~FPU_CSR_RM) |
1079 mips_rm[modeindex(value)];
1080 #ifdef CSRTRACE
1081 printk("%p gpr[%d]<-csr=%08x\n",
1082 (void *) (xcp->cp0_epc),
1083 MIPSInst_RT(ir), value);
1084 #endif
1085 }
1086 else if (MIPSInst_RD(ir) == FPCREG_RID)
1087 value = 0;
1088 else
1089 value = 0;
1090 if (MIPSInst_RT(ir))
1091 xcp->regs[MIPSInst_RT(ir)] = value;
1092 break;
1093 }
1094
1095 case ctc_op:{
1096 /* copregister rd <- rt */
1097 u32 value;
1098
1099 if (MIPSInst_RT(ir) == 0)
1100 value = 0;
1101 else
1102 value = xcp->regs[MIPSInst_RT(ir)];
1103
1104 /* we only have one writable control reg
1105 */
1106 if (MIPSInst_RD(ir) == FPCREG_CSR) {
1107 #ifdef CSRTRACE
1108 printk("%p gpr[%d]->csr=%08x\n",
1109 (void *) (xcp->cp0_epc),
1110 MIPSInst_RT(ir), value);
1111 #endif
1112
1113 /*
1114 * Don't write reserved bits,
1115 * and convert to ieee library modes
1116 */
1117 ctx->fcr31 = (value &
1118 ~(FPU_CSR_RSVD | FPU_CSR_RM)) |
1119 ieee_rm[modeindex(value)];
1120 }
1121 if ((ctx->fcr31 >> 5) & ctx->fcr31 & FPU_CSR_ALL_E) {
1122 return SIGFPE;
1123 }
1124 break;
1125 }
1126
1127 case bc_op:{
1128 int likely = 0;
1129
1130 if (xcp->cp0_cause & CAUSEF_BD)
1131 return SIGILL;
1132
1133 #if __mips >= 4
1134 cond = ctx->fcr31 & fpucondbit[MIPSInst_RT(ir) >> 2];
1135 #else
1136 cond = ctx->fcr31 & FPU_CSR_COND;
1137 #endif
1138 switch (MIPSInst_RT(ir) & 3) {
1139 case bcfl_op:
1140 likely = 1;
1141 case bcf_op:
1142 cond = !cond;
1143 break;
1144 case bctl_op:
1145 likely = 1;
1146 case bct_op:
1147 break;
1148 default:
1149 /* thats an illegal instruction */
1150 return SIGILL;
1151 }
1152
1153 xcp->cp0_cause |= CAUSEF_BD;
1154 if (cond) {
1155 /* branch taken: emulate dslot
1156 * instruction
1157 */
1158 xcp->cp0_epc += dec_insn.pc_inc;
1159
1160 contpc = MIPSInst_SIMM(ir);
1161 ir = dec_insn.next_insn;
1162 if (dec_insn.micro_mips_mode) {
1163 contpc = (xcp->cp0_epc + (contpc << 1));
1164
1165 /* If 16-bit instruction, not FPU. */
1166 if ((dec_insn.next_pc_inc == 2) ||
1167 (microMIPS32_to_MIPS32((union mips_instruction *)&ir) == SIGILL)) {
1168
1169 /*
1170 * Since this instruction will
1171 * be put on the stack with
1172 * 32-bit words, get around
1173 * this problem by putting a
1174 * NOP16 as the second one.
1175 */
1176 if (dec_insn.next_pc_inc == 2)
1177 ir = (ir & (~0xffff)) | MM_NOP16;
1178
1179 /*
1180 * Single step the non-CP1
1181 * instruction in the dslot.
1182 */
1183 return mips_dsemul(xcp, ir, contpc);
1184 }
1185 } else
1186 contpc = (xcp->cp0_epc + (contpc << 2));
1187
1188 switch (MIPSInst_OPCODE(ir)) {
1189 case lwc1_op:
1190 case swc1_op:
1191 #if (__mips >= 2 || defined(__mips64))
1192 case ldc1_op:
1193 case sdc1_op:
1194 #endif
1195 case cop1_op:
1196 #if __mips >= 4 && __mips != 32
1197 case cop1x_op:
1198 #endif
1199 /* its one of ours */
1200 goto emul;
1201 #if __mips >= 4
1202 case spec_op:
1203 if (MIPSInst_FUNC(ir) == movc_op)
1204 goto emul;
1205 break;
1206 #endif
1207 }
1208
1209 /*
1210 * Single step the non-cp1
1211 * instruction in the dslot
1212 */
1213 return mips_dsemul(xcp, ir, contpc);
1214 }
1215 else {
1216 /* branch not taken */
1217 if (likely) {
1218 /*
1219 * branch likely nullifies
1220 * dslot if not taken
1221 */
1222 xcp->cp0_epc += dec_insn.pc_inc;
1223 contpc += dec_insn.pc_inc;
1224 /*
1225 * else continue & execute
1226 * dslot as normal insn
1227 */
1228 }
1229 }
1230 break;
1231 }
1232
1233 default:
1234 if (!(MIPSInst_RS(ir) & 0x10))
1235 return SIGILL;
1236 {
1237 int sig;
1238
1239 /* a real fpu computation instruction */
1240 if ((sig = fpu_emu(xcp, ctx, ir)))
1241 return sig;
1242 }
1243 }
1244 break;
1245
1246 #if __mips >= 4 && __mips != 32
1247 case cop1x_op:{
1248 int sig = fpux_emu(xcp, ctx, ir, fault_addr);
1249 if (sig)
1250 return sig;
1251 break;
1252 }
1253 #endif
1254
1255 #if __mips >= 4
1256 case spec_op:
1257 if (MIPSInst_FUNC(ir) != movc_op)
1258 return SIGILL;
1259 cond = fpucondbit[MIPSInst_RT(ir) >> 2];
1260 if (((ctx->fcr31 & cond) != 0) == ((MIPSInst_RT(ir) & 1) != 0))
1261 xcp->regs[MIPSInst_RD(ir)] =
1262 xcp->regs[MIPSInst_RS(ir)];
1263 break;
1264 #endif
1265
1266 default:
1267 return SIGILL;
1268 }
1269
1270 /* we did it !! */
1271 xcp->cp0_epc = contpc;
1272 xcp->cp0_cause &= ~CAUSEF_BD;
1273
1274 return 0;
1275 }
1276
1277 /*
1278 * Conversion table from MIPS compare ops 48-63
1279 * cond = ieee754dp_cmp(x,y,IEEE754_UN,sig);
1280 */
1281 static const unsigned char cmptab[8] = {
1282 0, /* cmp_0 (sig) cmp_sf */
1283 IEEE754_CUN, /* cmp_un (sig) cmp_ngle */
1284 IEEE754_CEQ, /* cmp_eq (sig) cmp_seq */
1285 IEEE754_CEQ | IEEE754_CUN, /* cmp_ueq (sig) cmp_ngl */
1286 IEEE754_CLT, /* cmp_olt (sig) cmp_lt */
1287 IEEE754_CLT | IEEE754_CUN, /* cmp_ult (sig) cmp_nge */
1288 IEEE754_CLT | IEEE754_CEQ, /* cmp_ole (sig) cmp_le */
1289 IEEE754_CLT | IEEE754_CEQ | IEEE754_CUN, /* cmp_ule (sig) cmp_ngt */
1290 };
1291
1292
1293 #if __mips >= 4 && __mips != 32
1294
1295 /*
1296 * Additional MIPS4 instructions
1297 */
1298
1299 #define DEF3OP(name, p, f1, f2, f3) \
1300 static ieee754##p fpemu_##p##_##name(ieee754##p r, ieee754##p s, \
1301 ieee754##p t) \
1302 { \
1303 struct _ieee754_csr ieee754_csr_save; \
1304 s = f1(s, t); \
1305 ieee754_csr_save = ieee754_csr; \
1306 s = f2(s, r); \
1307 ieee754_csr_save.cx |= ieee754_csr.cx; \
1308 ieee754_csr_save.sx |= ieee754_csr.sx; \
1309 s = f3(s); \
1310 ieee754_csr.cx |= ieee754_csr_save.cx; \
1311 ieee754_csr.sx |= ieee754_csr_save.sx; \
1312 return s; \
1313 }
1314
1315 static ieee754dp fpemu_dp_recip(ieee754dp d)
1316 {
1317 return ieee754dp_div(ieee754dp_one(0), d);
1318 }
1319
1320 static ieee754dp fpemu_dp_rsqrt(ieee754dp d)
1321 {
1322 return ieee754dp_div(ieee754dp_one(0), ieee754dp_sqrt(d));
1323 }
1324
1325 static ieee754sp fpemu_sp_recip(ieee754sp s)
1326 {
1327 return ieee754sp_div(ieee754sp_one(0), s);
1328 }
1329
1330 static ieee754sp fpemu_sp_rsqrt(ieee754sp s)
1331 {
1332 return ieee754sp_div(ieee754sp_one(0), ieee754sp_sqrt(s));
1333 }
1334
1335 DEF3OP(madd, sp, ieee754sp_mul, ieee754sp_add, );
1336 DEF3OP(msub, sp, ieee754sp_mul, ieee754sp_sub, );
1337 DEF3OP(nmadd, sp, ieee754sp_mul, ieee754sp_add, ieee754sp_neg);
1338 DEF3OP(nmsub, sp, ieee754sp_mul, ieee754sp_sub, ieee754sp_neg);
1339 DEF3OP(madd, dp, ieee754dp_mul, ieee754dp_add, );
1340 DEF3OP(msub, dp, ieee754dp_mul, ieee754dp_sub, );
1341 DEF3OP(nmadd, dp, ieee754dp_mul, ieee754dp_add, ieee754dp_neg);
1342 DEF3OP(nmsub, dp, ieee754dp_mul, ieee754dp_sub, ieee754dp_neg);
1343
1344 static int fpux_emu(struct pt_regs *xcp, struct mips_fpu_struct *ctx,
1345 mips_instruction ir, void *__user *fault_addr)
1346 {
1347 unsigned rcsr = 0; /* resulting csr */
1348
1349 MIPS_FPU_EMU_INC_STATS(cp1xops);
1350
1351 switch (MIPSInst_FMA_FFMT(ir)) {
1352 case s_fmt:{ /* 0 */
1353
1354 ieee754sp(*handler) (ieee754sp, ieee754sp, ieee754sp);
1355 ieee754sp fd, fr, fs, ft;
1356 u32 __user *va;
1357 u32 val;
1358
1359 switch (MIPSInst_FUNC(ir)) {
1360 case lwxc1_op:
1361 va = (void __user *) (xcp->regs[MIPSInst_FR(ir)] +
1362 xcp->regs[MIPSInst_FT(ir)]);
1363
1364 MIPS_FPU_EMU_INC_STATS(loads);
1365 if (!access_ok(VERIFY_READ, va, sizeof(u32))) {
1366 MIPS_FPU_EMU_INC_STATS(errors);
1367 *fault_addr = va;
1368 return SIGBUS;
1369 }
1370 if (__get_user(val, va)) {
1371 MIPS_FPU_EMU_INC_STATS(errors);
1372 *fault_addr = va;
1373 return SIGSEGV;
1374 }
1375 SITOREG(val, MIPSInst_FD(ir));
1376 break;
1377
1378 case swxc1_op:
1379 va = (void __user *) (xcp->regs[MIPSInst_FR(ir)] +
1380 xcp->regs[MIPSInst_FT(ir)]);
1381
1382 MIPS_FPU_EMU_INC_STATS(stores);
1383
1384 SIFROMREG(val, MIPSInst_FS(ir));
1385 if (!access_ok(VERIFY_WRITE, va, sizeof(u32))) {
1386 MIPS_FPU_EMU_INC_STATS(errors);
1387 *fault_addr = va;
1388 return SIGBUS;
1389 }
1390 if (put_user(val, va)) {
1391 MIPS_FPU_EMU_INC_STATS(errors);
1392 *fault_addr = va;
1393 return SIGSEGV;
1394 }
1395 break;
1396
1397 case madd_s_op:
1398 handler = fpemu_sp_madd;
1399 goto scoptop;
1400 case msub_s_op:
1401 handler = fpemu_sp_msub;
1402 goto scoptop;
1403 case nmadd_s_op:
1404 handler = fpemu_sp_nmadd;
1405 goto scoptop;
1406 case nmsub_s_op:
1407 handler = fpemu_sp_nmsub;
1408 goto scoptop;
1409
1410 scoptop:
1411 SPFROMREG(fr, MIPSInst_FR(ir));
1412 SPFROMREG(fs, MIPSInst_FS(ir));
1413 SPFROMREG(ft, MIPSInst_FT(ir));
1414 fd = (*handler) (fr, fs, ft);
1415 SPTOREG(fd, MIPSInst_FD(ir));
1416
1417 copcsr:
1418 if (ieee754_cxtest(IEEE754_INEXACT))
1419 rcsr |= FPU_CSR_INE_X | FPU_CSR_INE_S;
1420 if (ieee754_cxtest(IEEE754_UNDERFLOW))
1421 rcsr |= FPU_CSR_UDF_X | FPU_CSR_UDF_S;
1422 if (ieee754_cxtest(IEEE754_OVERFLOW))
1423 rcsr |= FPU_CSR_OVF_X | FPU_CSR_OVF_S;
1424 if (ieee754_cxtest(IEEE754_INVALID_OPERATION))
1425 rcsr |= FPU_CSR_INV_X | FPU_CSR_INV_S;
1426
1427 ctx->fcr31 = (ctx->fcr31 & ~FPU_CSR_ALL_X) | rcsr;
1428 if ((ctx->fcr31 >> 5) & ctx->fcr31 & FPU_CSR_ALL_E) {
1429 /*printk ("SIGFPE: fpu csr = %08x\n",
1430 ctx->fcr31); */
1431 return SIGFPE;
1432 }
1433
1434 break;
1435
1436 default:
1437 return SIGILL;
1438 }
1439 break;
1440 }
1441
1442 case d_fmt:{ /* 1 */
1443 ieee754dp(*handler) (ieee754dp, ieee754dp, ieee754dp);
1444 ieee754dp fd, fr, fs, ft;
1445 u64 __user *va;
1446 u64 val;
1447
1448 switch (MIPSInst_FUNC(ir)) {
1449 case ldxc1_op:
1450 va = (void __user *) (xcp->regs[MIPSInst_FR(ir)] +
1451 xcp->regs[MIPSInst_FT(ir)]);
1452
1453 MIPS_FPU_EMU_INC_STATS(loads);
1454 if (!access_ok(VERIFY_READ, va, sizeof(u64))) {
1455 MIPS_FPU_EMU_INC_STATS(errors);
1456 *fault_addr = va;
1457 return SIGBUS;
1458 }
1459 if (__get_user(val, va)) {
1460 MIPS_FPU_EMU_INC_STATS(errors);
1461 *fault_addr = va;
1462 return SIGSEGV;
1463 }
1464 DITOREG(val, MIPSInst_FD(ir));
1465 break;
1466
1467 case sdxc1_op:
1468 va = (void __user *) (xcp->regs[MIPSInst_FR(ir)] +
1469 xcp->regs[MIPSInst_FT(ir)]);
1470
1471 MIPS_FPU_EMU_INC_STATS(stores);
1472 DIFROMREG(val, MIPSInst_FS(ir));
1473 if (!access_ok(VERIFY_WRITE, va, sizeof(u64))) {
1474 MIPS_FPU_EMU_INC_STATS(errors);
1475 *fault_addr = va;
1476 return SIGBUS;
1477 }
1478 if (__put_user(val, va)) {
1479 MIPS_FPU_EMU_INC_STATS(errors);
1480 *fault_addr = va;
1481 return SIGSEGV;
1482 }
1483 break;
1484
1485 case madd_d_op:
1486 handler = fpemu_dp_madd;
1487 goto dcoptop;
1488 case msub_d_op:
1489 handler = fpemu_dp_msub;
1490 goto dcoptop;
1491 case nmadd_d_op:
1492 handler = fpemu_dp_nmadd;
1493 goto dcoptop;
1494 case nmsub_d_op:
1495 handler = fpemu_dp_nmsub;
1496 goto dcoptop;
1497
1498 dcoptop:
1499 DPFROMREG(fr, MIPSInst_FR(ir));
1500 DPFROMREG(fs, MIPSInst_FS(ir));
1501 DPFROMREG(ft, MIPSInst_FT(ir));
1502 fd = (*handler) (fr, fs, ft);
1503 DPTOREG(fd, MIPSInst_FD(ir));
1504 goto copcsr;
1505
1506 default:
1507 return SIGILL;
1508 }
1509 break;
1510 }
1511
1512 case 0x7: /* 7 */
1513 if (MIPSInst_FUNC(ir) != pfetch_op) {
1514 return SIGILL;
1515 }
1516 /* ignore prefx operation */
1517 break;
1518
1519 default:
1520 return SIGILL;
1521 }
1522
1523 return 0;
1524 }
1525 #endif
1526
1527
1528
1529 /*
1530 * Emulate a single COP1 arithmetic instruction.
1531 */
1532 static int fpu_emu(struct pt_regs *xcp, struct mips_fpu_struct *ctx,
1533 mips_instruction ir)
1534 {
1535 int rfmt; /* resulting format */
1536 unsigned rcsr = 0; /* resulting csr */
1537 unsigned cond;
1538 union {
1539 ieee754dp d;
1540 ieee754sp s;
1541 int w;
1542 #ifdef __mips64
1543 s64 l;
1544 #endif
1545 } rv; /* resulting value */
1546
1547 MIPS_FPU_EMU_INC_STATS(cp1ops);
1548 switch (rfmt = (MIPSInst_FFMT(ir) & 0xf)) {
1549 case s_fmt:{ /* 0 */
1550 union {
1551 ieee754sp(*b) (ieee754sp, ieee754sp);
1552 ieee754sp(*u) (ieee754sp);
1553 } handler;
1554
1555 switch (MIPSInst_FUNC(ir)) {
1556 /* binary ops */
1557 case fadd_op:
1558 handler.b = ieee754sp_add;
1559 goto scopbop;
1560 case fsub_op:
1561 handler.b = ieee754sp_sub;
1562 goto scopbop;
1563 case fmul_op:
1564 handler.b = ieee754sp_mul;
1565 goto scopbop;
1566 case fdiv_op:
1567 handler.b = ieee754sp_div;
1568 goto scopbop;
1569
1570 /* unary ops */
1571 #if __mips >= 2 || defined(__mips64)
1572 case fsqrt_op:
1573 handler.u = ieee754sp_sqrt;
1574 goto scopuop;
1575 #endif
1576 #if __mips >= 4 && __mips != 32
1577 case frsqrt_op:
1578 handler.u = fpemu_sp_rsqrt;
1579 goto scopuop;
1580 case frecip_op:
1581 handler.u = fpemu_sp_recip;
1582 goto scopuop;
1583 #endif
1584 #if __mips >= 4
1585 case fmovc_op:
1586 cond = fpucondbit[MIPSInst_FT(ir) >> 2];
1587 if (((ctx->fcr31 & cond) != 0) !=
1588 ((MIPSInst_FT(ir) & 1) != 0))
1589 return 0;
1590 SPFROMREG(rv.s, MIPSInst_FS(ir));
1591 break;
1592 case fmovz_op:
1593 if (xcp->regs[MIPSInst_FT(ir)] != 0)
1594 return 0;
1595 SPFROMREG(rv.s, MIPSInst_FS(ir));
1596 break;
1597 case fmovn_op:
1598 if (xcp->regs[MIPSInst_FT(ir)] == 0)
1599 return 0;
1600 SPFROMREG(rv.s, MIPSInst_FS(ir));
1601 break;
1602 #endif
1603 case fabs_op:
1604 handler.u = ieee754sp_abs;
1605 goto scopuop;
1606 case fneg_op:
1607 handler.u = ieee754sp_neg;
1608 goto scopuop;
1609 case fmov_op:
1610 /* an easy one */
1611 SPFROMREG(rv.s, MIPSInst_FS(ir));
1612 goto copcsr;
1613
1614 /* binary op on handler */
1615 scopbop:
1616 {
1617 ieee754sp fs, ft;
1618
1619 SPFROMREG(fs, MIPSInst_FS(ir));
1620 SPFROMREG(ft, MIPSInst_FT(ir));
1621
1622 rv.s = (*handler.b) (fs, ft);
1623 goto copcsr;
1624 }
1625 scopuop:
1626 {
1627 ieee754sp fs;
1628
1629 SPFROMREG(fs, MIPSInst_FS(ir));
1630 rv.s = (*handler.u) (fs);
1631 goto copcsr;
1632 }
1633 copcsr:
1634 if (ieee754_cxtest(IEEE754_INEXACT))
1635 rcsr |= FPU_CSR_INE_X | FPU_CSR_INE_S;
1636 if (ieee754_cxtest(IEEE754_UNDERFLOW))
1637 rcsr |= FPU_CSR_UDF_X | FPU_CSR_UDF_S;
1638 if (ieee754_cxtest(IEEE754_OVERFLOW))
1639 rcsr |= FPU_CSR_OVF_X | FPU_CSR_OVF_S;
1640 if (ieee754_cxtest(IEEE754_ZERO_DIVIDE))
1641 rcsr |= FPU_CSR_DIV_X | FPU_CSR_DIV_S;
1642 if (ieee754_cxtest(IEEE754_INVALID_OPERATION))
1643 rcsr |= FPU_CSR_INV_X | FPU_CSR_INV_S;
1644 break;
1645
1646 /* unary conv ops */
1647 case fcvts_op:
1648 return SIGILL; /* not defined */
1649 case fcvtd_op:{
1650 ieee754sp fs;
1651
1652 SPFROMREG(fs, MIPSInst_FS(ir));
1653 rv.d = ieee754dp_fsp(fs);
1654 rfmt = d_fmt;
1655 goto copcsr;
1656 }
1657 case fcvtw_op:{
1658 ieee754sp fs;
1659
1660 SPFROMREG(fs, MIPSInst_FS(ir));
1661 rv.w = ieee754sp_tint(fs);
1662 rfmt = w_fmt;
1663 goto copcsr;
1664 }
1665
1666 #if __mips >= 2 || defined(__mips64)
1667 case fround_op:
1668 case ftrunc_op:
1669 case fceil_op:
1670 case ffloor_op:{
1671 unsigned int oldrm = ieee754_csr.rm;
1672 ieee754sp fs;
1673
1674 SPFROMREG(fs, MIPSInst_FS(ir));
1675 ieee754_csr.rm = ieee_rm[modeindex(MIPSInst_FUNC(ir))];
1676 rv.w = ieee754sp_tint(fs);
1677 ieee754_csr.rm = oldrm;
1678 rfmt = w_fmt;
1679 goto copcsr;
1680 }
1681 #endif /* __mips >= 2 */
1682
1683 #if defined(__mips64)
1684 case fcvtl_op:{
1685 ieee754sp fs;
1686
1687 SPFROMREG(fs, MIPSInst_FS(ir));
1688 rv.l = ieee754sp_tlong(fs);
1689 rfmt = l_fmt;
1690 goto copcsr;
1691 }
1692
1693 case froundl_op:
1694 case ftruncl_op:
1695 case fceill_op:
1696 case ffloorl_op:{
1697 unsigned int oldrm = ieee754_csr.rm;
1698 ieee754sp fs;
1699
1700 SPFROMREG(fs, MIPSInst_FS(ir));
1701 ieee754_csr.rm = ieee_rm[modeindex(MIPSInst_FUNC(ir))];
1702 rv.l = ieee754sp_tlong(fs);
1703 ieee754_csr.rm = oldrm;
1704 rfmt = l_fmt;
1705 goto copcsr;
1706 }
1707 #endif /* defined(__mips64) */
1708
1709 default:
1710 if (MIPSInst_FUNC(ir) >= fcmp_op) {
1711 unsigned cmpop = MIPSInst_FUNC(ir) - fcmp_op;
1712 ieee754sp fs, ft;
1713
1714 SPFROMREG(fs, MIPSInst_FS(ir));
1715 SPFROMREG(ft, MIPSInst_FT(ir));
1716 rv.w = ieee754sp_cmp(fs, ft,
1717 cmptab[cmpop & 0x7], cmpop & 0x8);
1718 rfmt = -1;
1719 if ((cmpop & 0x8) && ieee754_cxtest
1720 (IEEE754_INVALID_OPERATION))
1721 rcsr = FPU_CSR_INV_X | FPU_CSR_INV_S;
1722 else
1723 goto copcsr;
1724
1725 }
1726 else {
1727 return SIGILL;
1728 }
1729 break;
1730 }
1731 break;
1732 }
1733
1734 case d_fmt:{
1735 union {
1736 ieee754dp(*b) (ieee754dp, ieee754dp);
1737 ieee754dp(*u) (ieee754dp);
1738 } handler;
1739
1740 switch (MIPSInst_FUNC(ir)) {
1741 /* binary ops */
1742 case fadd_op:
1743 handler.b = ieee754dp_add;
1744 goto dcopbop;
1745 case fsub_op:
1746 handler.b = ieee754dp_sub;
1747 goto dcopbop;
1748 case fmul_op:
1749 handler.b = ieee754dp_mul;
1750 goto dcopbop;
1751 case fdiv_op:
1752 handler.b = ieee754dp_div;
1753 goto dcopbop;
1754
1755 /* unary ops */
1756 #if __mips >= 2 || defined(__mips64)
1757 case fsqrt_op:
1758 handler.u = ieee754dp_sqrt;
1759 goto dcopuop;
1760 #endif
1761 #if __mips >= 4 && __mips != 32
1762 case frsqrt_op:
1763 handler.u = fpemu_dp_rsqrt;
1764 goto dcopuop;
1765 case frecip_op:
1766 handler.u = fpemu_dp_recip;
1767 goto dcopuop;
1768 #endif
1769 #if __mips >= 4
1770 case fmovc_op:
1771 cond = fpucondbit[MIPSInst_FT(ir) >> 2];
1772 if (((ctx->fcr31 & cond) != 0) !=
1773 ((MIPSInst_FT(ir) & 1) != 0))
1774 return 0;
1775 DPFROMREG(rv.d, MIPSInst_FS(ir));
1776 break;
1777 case fmovz_op:
1778 if (xcp->regs[MIPSInst_FT(ir)] != 0)
1779 return 0;
1780 DPFROMREG(rv.d, MIPSInst_FS(ir));
1781 break;
1782 case fmovn_op:
1783 if (xcp->regs[MIPSInst_FT(ir)] == 0)
1784 return 0;
1785 DPFROMREG(rv.d, MIPSInst_FS(ir));
1786 break;
1787 #endif
1788 case fabs_op:
1789 handler.u = ieee754dp_abs;
1790 goto dcopuop;
1791
1792 case fneg_op:
1793 handler.u = ieee754dp_neg;
1794 goto dcopuop;
1795
1796 case fmov_op:
1797 /* an easy one */
1798 DPFROMREG(rv.d, MIPSInst_FS(ir));
1799 goto copcsr;
1800
1801 /* binary op on handler */
1802 dcopbop:{
1803 ieee754dp fs, ft;
1804
1805 DPFROMREG(fs, MIPSInst_FS(ir));
1806 DPFROMREG(ft, MIPSInst_FT(ir));
1807
1808 rv.d = (*handler.b) (fs, ft);
1809 goto copcsr;
1810 }
1811 dcopuop:{
1812 ieee754dp fs;
1813
1814 DPFROMREG(fs, MIPSInst_FS(ir));
1815 rv.d = (*handler.u) (fs);
1816 goto copcsr;
1817 }
1818
1819 /* unary conv ops */
1820 case fcvts_op:{
1821 ieee754dp fs;
1822
1823 DPFROMREG(fs, MIPSInst_FS(ir));
1824 rv.s = ieee754sp_fdp(fs);
1825 rfmt = s_fmt;
1826 goto copcsr;
1827 }
1828 case fcvtd_op:
1829 return SIGILL; /* not defined */
1830
1831 case fcvtw_op:{
1832 ieee754dp fs;
1833
1834 DPFROMREG(fs, MIPSInst_FS(ir));
1835 rv.w = ieee754dp_tint(fs); /* wrong */
1836 rfmt = w_fmt;
1837 goto copcsr;
1838 }
1839
1840 #if __mips >= 2 || defined(__mips64)
1841 case fround_op:
1842 case ftrunc_op:
1843 case fceil_op:
1844 case ffloor_op:{
1845 unsigned int oldrm = ieee754_csr.rm;
1846 ieee754dp fs;
1847
1848 DPFROMREG(fs, MIPSInst_FS(ir));
1849 ieee754_csr.rm = ieee_rm[modeindex(MIPSInst_FUNC(ir))];
1850 rv.w = ieee754dp_tint(fs);
1851 ieee754_csr.rm = oldrm;
1852 rfmt = w_fmt;
1853 goto copcsr;
1854 }
1855 #endif
1856
1857 #if defined(__mips64)
1858 case fcvtl_op:{
1859 ieee754dp fs;
1860
1861 DPFROMREG(fs, MIPSInst_FS(ir));
1862 rv.l = ieee754dp_tlong(fs);
1863 rfmt = l_fmt;
1864 goto copcsr;
1865 }
1866
1867 case froundl_op:
1868 case ftruncl_op:
1869 case fceill_op:
1870 case ffloorl_op:{
1871 unsigned int oldrm = ieee754_csr.rm;
1872 ieee754dp fs;
1873
1874 DPFROMREG(fs, MIPSInst_FS(ir));
1875 ieee754_csr.rm = ieee_rm[modeindex(MIPSInst_FUNC(ir))];
1876 rv.l = ieee754dp_tlong(fs);
1877 ieee754_csr.rm = oldrm;
1878 rfmt = l_fmt;
1879 goto copcsr;
1880 }
1881 #endif /* __mips >= 3 */
1882
1883 default:
1884 if (MIPSInst_FUNC(ir) >= fcmp_op) {
1885 unsigned cmpop = MIPSInst_FUNC(ir) - fcmp_op;
1886 ieee754dp fs, ft;
1887
1888 DPFROMREG(fs, MIPSInst_FS(ir));
1889 DPFROMREG(ft, MIPSInst_FT(ir));
1890 rv.w = ieee754dp_cmp(fs, ft,
1891 cmptab[cmpop & 0x7], cmpop & 0x8);
1892 rfmt = -1;
1893 if ((cmpop & 0x8)
1894 &&
1895 ieee754_cxtest
1896 (IEEE754_INVALID_OPERATION))
1897 rcsr = FPU_CSR_INV_X | FPU_CSR_INV_S;
1898 else
1899 goto copcsr;
1900
1901 }
1902 else {
1903 return SIGILL;
1904 }
1905 break;
1906 }
1907 break;
1908 }
1909
1910 case w_fmt:{
1911 ieee754sp fs;
1912
1913 switch (MIPSInst_FUNC(ir)) {
1914 case fcvts_op:
1915 /* convert word to single precision real */
1916 SPFROMREG(fs, MIPSInst_FS(ir));
1917 rv.s = ieee754sp_fint(fs.bits);
1918 rfmt = s_fmt;
1919 goto copcsr;
1920 case fcvtd_op:
1921 /* convert word to double precision real */
1922 SPFROMREG(fs, MIPSInst_FS(ir));
1923 rv.d = ieee754dp_fint(fs.bits);
1924 rfmt = d_fmt;
1925 goto copcsr;
1926 default:
1927 return SIGILL;
1928 }
1929 break;
1930 }
1931
1932 #if defined(__mips64)
1933 case l_fmt:{
1934 switch (MIPSInst_FUNC(ir)) {
1935 case fcvts_op:
1936 /* convert long to single precision real */
1937 rv.s = ieee754sp_flong(ctx->fpr[MIPSInst_FS(ir)]);
1938 rfmt = s_fmt;
1939 goto copcsr;
1940 case fcvtd_op:
1941 /* convert long to double precision real */
1942 rv.d = ieee754dp_flong(ctx->fpr[MIPSInst_FS(ir)]);
1943 rfmt = d_fmt;
1944 goto copcsr;
1945 default:
1946 return SIGILL;
1947 }
1948 break;
1949 }
1950 #endif
1951
1952 default:
1953 return SIGILL;
1954 }
1955
1956 /*
1957 * Update the fpu CSR register for this operation.
1958 * If an exception is required, generate a tidy SIGFPE exception,
1959 * without updating the result register.
1960 * Note: cause exception bits do not accumulate, they are rewritten
1961 * for each op; only the flag/sticky bits accumulate.
1962 */
1963 ctx->fcr31 = (ctx->fcr31 & ~FPU_CSR_ALL_X) | rcsr;
1964 if ((ctx->fcr31 >> 5) & ctx->fcr31 & FPU_CSR_ALL_E) {
1965 /*printk ("SIGFPE: fpu csr = %08x\n",ctx->fcr31); */
1966 return SIGFPE;
1967 }
1968
1969 /*
1970 * Now we can safely write the result back to the register file.
1971 */
1972 switch (rfmt) {
1973 case -1:{
1974 #if __mips >= 4
1975 cond = fpucondbit[MIPSInst_FD(ir) >> 2];
1976 #else
1977 cond = FPU_CSR_COND;
1978 #endif
1979 if (rv.w)
1980 ctx->fcr31 |= cond;
1981 else
1982 ctx->fcr31 &= ~cond;
1983 break;
1984 }
1985 case d_fmt:
1986 DPTOREG(rv.d, MIPSInst_FD(ir));
1987 break;
1988 case s_fmt:
1989 SPTOREG(rv.s, MIPSInst_FD(ir));
1990 break;
1991 case w_fmt:
1992 SITOREG(rv.w, MIPSInst_FD(ir));
1993 break;
1994 #if defined(__mips64)
1995 case l_fmt:
1996 DITOREG(rv.l, MIPSInst_FD(ir));
1997 break;
1998 #endif
1999 default:
2000 return SIGILL;
2001 }
2002
2003 return 0;
2004 }
2005
2006 int fpu_emulator_cop1Handler(struct pt_regs *xcp, struct mips_fpu_struct *ctx,
2007 int has_fpu, void *__user *fault_addr)
2008 {
2009 unsigned long oldepc, prevepc;
2010 struct mm_decoded_insn dec_insn;
2011 u16 instr[4];
2012 u16 *instr_ptr;
2013 int sig = 0;
2014
2015 oldepc = xcp->cp0_epc;
2016 do {
2017 prevepc = xcp->cp0_epc;
2018
2019 if (get_isa16_mode(prevepc) && cpu_has_mmips) {
2020 /*
2021 * Get next 2 microMIPS instructions and convert them
2022 * into 32-bit instructions.
2023 */
2024 if ((get_user(instr[0], (u16 __user *)msk_isa16_mode(xcp->cp0_epc))) ||
2025 (get_user(instr[1], (u16 __user *)msk_isa16_mode(xcp->cp0_epc + 2))) ||
2026 (get_user(instr[2], (u16 __user *)msk_isa16_mode(xcp->cp0_epc + 4))) ||
2027 (get_user(instr[3], (u16 __user *)msk_isa16_mode(xcp->cp0_epc + 6)))) {
2028 MIPS_FPU_EMU_INC_STATS(errors);
2029 return SIGBUS;
2030 }
2031 instr_ptr = instr;
2032
2033 /* Get first instruction. */
2034 if (mm_insn_16bit(*instr_ptr)) {
2035 /* Duplicate the half-word. */
2036 dec_insn.insn = (*instr_ptr << 16) |
2037 (*instr_ptr);
2038 /* 16-bit instruction. */
2039 dec_insn.pc_inc = 2;
2040 instr_ptr += 1;
2041 } else {
2042 dec_insn.insn = (*instr_ptr << 16) |
2043 *(instr_ptr+1);
2044 /* 32-bit instruction. */
2045 dec_insn.pc_inc = 4;
2046 instr_ptr += 2;
2047 }
2048 /* Get second instruction. */
2049 if (mm_insn_16bit(*instr_ptr)) {
2050 /* Duplicate the half-word. */
2051 dec_insn.next_insn = (*instr_ptr << 16) |
2052 (*instr_ptr);
2053 /* 16-bit instruction. */
2054 dec_insn.next_pc_inc = 2;
2055 } else {
2056 dec_insn.next_insn = (*instr_ptr << 16) |
2057 *(instr_ptr+1);
2058 /* 32-bit instruction. */
2059 dec_insn.next_pc_inc = 4;
2060 }
2061 dec_insn.micro_mips_mode = 1;
2062 } else {
2063 if ((get_user(dec_insn.insn,
2064 (mips_instruction __user *) xcp->cp0_epc)) ||
2065 (get_user(dec_insn.next_insn,
2066 (mips_instruction __user *)(xcp->cp0_epc+4)))) {
2067 MIPS_FPU_EMU_INC_STATS(errors);
2068 return SIGBUS;
2069 }
2070 dec_insn.pc_inc = 4;
2071 dec_insn.next_pc_inc = 4;
2072 dec_insn.micro_mips_mode = 0;
2073 }
2074
2075 if ((dec_insn.insn == 0) ||
2076 ((dec_insn.pc_inc == 2) &&
2077 ((dec_insn.insn & 0xffff) == MM_NOP16)))
2078 xcp->cp0_epc += dec_insn.pc_inc; /* Skip NOPs */
2079 else {
2080 /*
2081 * The 'ieee754_csr' is an alias of
2082 * ctx->fcr31. No need to copy ctx->fcr31 to
2083 * ieee754_csr. But ieee754_csr.rm is ieee
2084 * library modes. (not mips rounding mode)
2085 */
2086 /* convert to ieee library modes */
2087 ieee754_csr.rm = ieee_rm[ieee754_csr.rm];
2088 sig = cop1Emulate(xcp, ctx, dec_insn, fault_addr);
2089 /* revert to mips rounding mode */
2090 ieee754_csr.rm = mips_rm[ieee754_csr.rm];
2091 }
2092
2093 if (has_fpu)
2094 break;
2095 if (sig)
2096 break;
2097
2098 cond_resched();
2099 } while (xcp->cp0_epc > prevepc);
2100
2101 /* SIGILL indicates a non-fpu instruction */
2102 if (sig == SIGILL && xcp->cp0_epc != oldepc)
2103 /* but if epc has advanced, then ignore it */
2104 sig = 0;
2105
2106 return sig;
2107 }
2108
2109 #ifdef CONFIG_DEBUG_FS
2110
2111 static int fpuemu_stat_get(void *data, u64 *val)
2112 {
2113 int cpu;
2114 unsigned long sum = 0;
2115 for_each_online_cpu(cpu) {
2116 struct mips_fpu_emulator_stats *ps;
2117 local_t *pv;
2118 ps = &per_cpu(fpuemustats, cpu);
2119 pv = (void *)ps + (unsigned long)data;
2120 sum += local_read(pv);
2121 }
2122 *val = sum;
2123 return 0;
2124 }
2125 DEFINE_SIMPLE_ATTRIBUTE(fops_fpuemu_stat, fpuemu_stat_get, NULL, "%llu\n");
2126
2127 extern struct dentry *mips_debugfs_dir;
2128 static int __init debugfs_fpuemu(void)
2129 {
2130 struct dentry *d, *dir;
2131
2132 if (!mips_debugfs_dir)
2133 return -ENODEV;
2134 dir = debugfs_create_dir("fpuemustats", mips_debugfs_dir);
2135 if (!dir)
2136 return -ENOMEM;
2137
2138 #define FPU_STAT_CREATE(M) \
2139 do { \
2140 d = debugfs_create_file(#M , S_IRUGO, dir, \
2141 (void *)offsetof(struct mips_fpu_emulator_stats, M), \
2142 &fops_fpuemu_stat); \
2143 if (!d) \
2144 return -ENOMEM; \
2145 } while (0)
2146
2147 FPU_STAT_CREATE(emulated);
2148 FPU_STAT_CREATE(loads);
2149 FPU_STAT_CREATE(stores);
2150 FPU_STAT_CREATE(cp1ops);
2151 FPU_STAT_CREATE(cp1xops);
2152 FPU_STAT_CREATE(errors);
2153
2154 return 0;
2155 }
2156 __initcall(debugfs_fpuemu);
2157 #endif
Linus' kernel tree