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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 * 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 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/debugfs.h>
38#include <linux/percpu-defs.h>
39#include <linux/perf_event.h>
40
41#include <asm/branch.h>
42#include <asm/inst.h>
43#include <asm/ptrace.h>
44#include <asm/signal.h>
45#include <linux/uaccess.h>
46
47#include <asm/cpu-info.h>
48#include <asm/processor.h>
49#include <asm/fpu_emulator.h>
50#include <asm/fpu.h>
51#include <asm/mips-r2-to-r6-emul.h>
52
53#include "ieee754.h"
54
55/* Function which emulates a floating point instruction. */
56
57static int fpu_emu(struct pt_regs *, struct mips_fpu_struct *,
58 mips_instruction);
59
60static int fpux_emu(struct pt_regs *,
61 struct mips_fpu_struct *, mips_instruction, void __user **);
62
63/* Control registers */
64
65#define FPCREG_RID 0 /* $0 = revision id */
66#define FPCREG_FCCR 25 /* $25 = fccr */
67#define FPCREG_FEXR 26 /* $26 = fexr */
68#define FPCREG_FENR 28 /* $28 = fenr */
69#define FPCREG_CSR 31 /* $31 = csr */
70
71/* convert condition code register number to csr bit */
72const unsigned int fpucondbit[8] = {
73 FPU_CSR_COND,
74 FPU_CSR_COND1,
75 FPU_CSR_COND2,
76 FPU_CSR_COND3,
77 FPU_CSR_COND4,
78 FPU_CSR_COND5,
79 FPU_CSR_COND6,
80 FPU_CSR_COND7
81};
82
83/* (microMIPS) Convert certain microMIPS instructions to MIPS32 format. */
84static const int sd_format[] = {16, 17, 0, 0, 0, 0, 0, 0};
85static const int sdps_format[] = {16, 17, 22, 0, 0, 0, 0, 0};
86static const int dwl_format[] = {17, 20, 21, 0, 0, 0, 0, 0};
87static const int swl_format[] = {16, 20, 21, 0, 0, 0, 0, 0};
88
89/*
90 * This functions translates a 32-bit microMIPS instruction
91 * into a 32-bit MIPS32 instruction. Returns 0 on success
92 * and SIGILL otherwise.
93 */
94static int microMIPS32_to_MIPS32(union mips_instruction *insn_ptr)
95{
96 union mips_instruction insn = *insn_ptr;
97 union mips_instruction mips32_insn = insn;
98 int func, fmt, op;
99
100 switch (insn.mm_i_format.opcode) {
101 case mm_ldc132_op:
102 mips32_insn.mm_i_format.opcode = ldc1_op;
103 mips32_insn.mm_i_format.rt = insn.mm_i_format.rs;
104 mips32_insn.mm_i_format.rs = insn.mm_i_format.rt;
105 break;
106 case mm_lwc132_op:
107 mips32_insn.mm_i_format.opcode = lwc1_op;
108 mips32_insn.mm_i_format.rt = insn.mm_i_format.rs;
109 mips32_insn.mm_i_format.rs = insn.mm_i_format.rt;
110 break;
111 case mm_sdc132_op:
112 mips32_insn.mm_i_format.opcode = sdc1_op;
113 mips32_insn.mm_i_format.rt = insn.mm_i_format.rs;
114 mips32_insn.mm_i_format.rs = insn.mm_i_format.rt;
115 break;
116 case mm_swc132_op:
117 mips32_insn.mm_i_format.opcode = swc1_op;
118 mips32_insn.mm_i_format.rt = insn.mm_i_format.rs;
119 mips32_insn.mm_i_format.rs = insn.mm_i_format.rt;
120 break;
121 case mm_pool32i_op:
122 /* NOTE: offset is << by 1 if in microMIPS mode. */
123 if ((insn.mm_i_format.rt == mm_bc1f_op) ||
124 (insn.mm_i_format.rt == mm_bc1t_op)) {
125 mips32_insn.fb_format.opcode = cop1_op;
126 mips32_insn.fb_format.bc = bc_op;
127 mips32_insn.fb_format.flag =
128 (insn.mm_i_format.rt == mm_bc1t_op) ? 1 : 0;
129 } else
130 return SIGILL;
131 break;
132 case mm_pool32f_op:
133 switch (insn.mm_fp0_format.func) {
134 case mm_32f_01_op:
135 case mm_32f_11_op:
136 case mm_32f_02_op:
137 case mm_32f_12_op:
138 case mm_32f_41_op:
139 case mm_32f_51_op:
140 case mm_32f_42_op:
141 case mm_32f_52_op:
142 op = insn.mm_fp0_format.func;
143 if (op == mm_32f_01_op)
144 func = madd_s_op;
145 else if (op == mm_32f_11_op)
146 func = madd_d_op;
147 else if (op == mm_32f_02_op)
148 func = nmadd_s_op;
149 else if (op == mm_32f_12_op)
150 func = nmadd_d_op;
151 else if (op == mm_32f_41_op)
152 func = msub_s_op;
153 else if (op == mm_32f_51_op)
154 func = msub_d_op;
155 else if (op == mm_32f_42_op)
156 func = nmsub_s_op;
157 else
158 func = nmsub_d_op;
159 mips32_insn.fp6_format.opcode = cop1x_op;
160 mips32_insn.fp6_format.fr = insn.mm_fp6_format.fr;
161 mips32_insn.fp6_format.ft = insn.mm_fp6_format.ft;
162 mips32_insn.fp6_format.fs = insn.mm_fp6_format.fs;
163 mips32_insn.fp6_format.fd = insn.mm_fp6_format.fd;
164 mips32_insn.fp6_format.func = func;
165 break;
166 case mm_32f_10_op:
167 func = -1; /* Invalid */
168 op = insn.mm_fp5_format.op & 0x7;
169 if (op == mm_ldxc1_op)
170 func = ldxc1_op;
171 else if (op == mm_sdxc1_op)
172 func = sdxc1_op;
173 else if (op == mm_lwxc1_op)
174 func = lwxc1_op;
175 else if (op == mm_swxc1_op)
176 func = swxc1_op;
177
178 if (func != -1) {
179 mips32_insn.r_format.opcode = cop1x_op;
180 mips32_insn.r_format.rs =
181 insn.mm_fp5_format.base;
182 mips32_insn.r_format.rt =
183 insn.mm_fp5_format.index;
184 mips32_insn.r_format.rd = 0;
185 mips32_insn.r_format.re = insn.mm_fp5_format.fd;
186 mips32_insn.r_format.func = func;
187 } else
188 return SIGILL;
189 break;
190 case mm_32f_40_op:
191 op = -1; /* Invalid */
192 if (insn.mm_fp2_format.op == mm_fmovt_op)
193 op = 1;
194 else if (insn.mm_fp2_format.op == mm_fmovf_op)
195 op = 0;
196 if (op != -1) {
197 mips32_insn.fp0_format.opcode = cop1_op;
198 mips32_insn.fp0_format.fmt =
199 sdps_format[insn.mm_fp2_format.fmt];
200 mips32_insn.fp0_format.ft =
201 (insn.mm_fp2_format.cc<<2) + op;
202 mips32_insn.fp0_format.fs =
203 insn.mm_fp2_format.fs;
204 mips32_insn.fp0_format.fd =
205 insn.mm_fp2_format.fd;
206 mips32_insn.fp0_format.func = fmovc_op;
207 } else
208 return SIGILL;
209 break;
210 case mm_32f_60_op:
211 func = -1; /* Invalid */
212 if (insn.mm_fp0_format.op == mm_fadd_op)
213 func = fadd_op;
214 else if (insn.mm_fp0_format.op == mm_fsub_op)
215 func = fsub_op;
216 else if (insn.mm_fp0_format.op == mm_fmul_op)
217 func = fmul_op;
218 else if (insn.mm_fp0_format.op == mm_fdiv_op)
219 func = fdiv_op;
220 if (func != -1) {
221 mips32_insn.fp0_format.opcode = cop1_op;
222 mips32_insn.fp0_format.fmt =
223 sdps_format[insn.mm_fp0_format.fmt];
224 mips32_insn.fp0_format.ft =
225 insn.mm_fp0_format.ft;
226 mips32_insn.fp0_format.fs =
227 insn.mm_fp0_format.fs;
228 mips32_insn.fp0_format.fd =
229 insn.mm_fp0_format.fd;
230 mips32_insn.fp0_format.func = func;
231 } else
232 return SIGILL;
233 break;
234 case mm_32f_70_op:
235 func = -1; /* Invalid */
236 if (insn.mm_fp0_format.op == mm_fmovn_op)
237 func = fmovn_op;
238 else if (insn.mm_fp0_format.op == mm_fmovz_op)
239 func = fmovz_op;
240 if (func != -1) {
241 mips32_insn.fp0_format.opcode = cop1_op;
242 mips32_insn.fp0_format.fmt =
243 sdps_format[insn.mm_fp0_format.fmt];
244 mips32_insn.fp0_format.ft =
245 insn.mm_fp0_format.ft;
246 mips32_insn.fp0_format.fs =
247 insn.mm_fp0_format.fs;
248 mips32_insn.fp0_format.fd =
249 insn.mm_fp0_format.fd;
250 mips32_insn.fp0_format.func = func;
251 } else
252 return SIGILL;
253 break;
254 case mm_32f_73_op: /* POOL32FXF */
255 switch (insn.mm_fp1_format.op) {
256 case mm_movf0_op:
257 case mm_movf1_op:
258 case mm_movt0_op:
259 case mm_movt1_op:
260 if ((insn.mm_fp1_format.op & 0x7f) ==
261 mm_movf0_op)
262 op = 0;
263 else
264 op = 1;
265 mips32_insn.r_format.opcode = spec_op;
266 mips32_insn.r_format.rs = insn.mm_fp4_format.fs;
267 mips32_insn.r_format.rt =
268 (insn.mm_fp4_format.cc << 2) + op;
269 mips32_insn.r_format.rd = insn.mm_fp4_format.rt;
270 mips32_insn.r_format.re = 0;
271 mips32_insn.r_format.func = movc_op;
272 break;
273 case mm_fcvtd0_op:
274 case mm_fcvtd1_op:
275 case mm_fcvts0_op:
276 case mm_fcvts1_op:
277 if ((insn.mm_fp1_format.op & 0x7f) ==
278 mm_fcvtd0_op) {
279 func = fcvtd_op;
280 fmt = swl_format[insn.mm_fp3_format.fmt];
281 } else {
282 func = fcvts_op;
283 fmt = dwl_format[insn.mm_fp3_format.fmt];
284 }
285 mips32_insn.fp0_format.opcode = cop1_op;
286 mips32_insn.fp0_format.fmt = fmt;
287 mips32_insn.fp0_format.ft = 0;
288 mips32_insn.fp0_format.fs =
289 insn.mm_fp3_format.fs;
290 mips32_insn.fp0_format.fd =
291 insn.mm_fp3_format.rt;
292 mips32_insn.fp0_format.func = func;
293 break;
294 case mm_fmov0_op:
295 case mm_fmov1_op:
296 case mm_fabs0_op:
297 case mm_fabs1_op:
298 case mm_fneg0_op:
299 case mm_fneg1_op:
300 if ((insn.mm_fp1_format.op & 0x7f) ==
301 mm_fmov0_op)
302 func = fmov_op;
303 else if ((insn.mm_fp1_format.op & 0x7f) ==
304 mm_fabs0_op)
305 func = fabs_op;
306 else
307 func = fneg_op;
308 mips32_insn.fp0_format.opcode = cop1_op;
309 mips32_insn.fp0_format.fmt =
310 sdps_format[insn.mm_fp3_format.fmt];
311 mips32_insn.fp0_format.ft = 0;
312 mips32_insn.fp0_format.fs =
313 insn.mm_fp3_format.fs;
314 mips32_insn.fp0_format.fd =
315 insn.mm_fp3_format.rt;
316 mips32_insn.fp0_format.func = func;
317 break;
318 case mm_ffloorl_op:
319 case mm_ffloorw_op:
320 case mm_fceill_op:
321 case mm_fceilw_op:
322 case mm_ftruncl_op:
323 case mm_ftruncw_op:
324 case mm_froundl_op:
325 case mm_froundw_op:
326 case mm_fcvtl_op:
327 case mm_fcvtw_op:
328 if (insn.mm_fp1_format.op == mm_ffloorl_op)
329 func = ffloorl_op;
330 else if (insn.mm_fp1_format.op == mm_ffloorw_op)
331 func = ffloor_op;
332 else if (insn.mm_fp1_format.op == mm_fceill_op)
333 func = fceill_op;
334 else if (insn.mm_fp1_format.op == mm_fceilw_op)
335 func = fceil_op;
336 else if (insn.mm_fp1_format.op == mm_ftruncl_op)
337 func = ftruncl_op;
338 else if (insn.mm_fp1_format.op == mm_ftruncw_op)
339 func = ftrunc_op;
340 else if (insn.mm_fp1_format.op == mm_froundl_op)
341 func = froundl_op;
342 else if (insn.mm_fp1_format.op == mm_froundw_op)
343 func = fround_op;
344 else if (insn.mm_fp1_format.op == mm_fcvtl_op)
345 func = fcvtl_op;
346 else
347 func = fcvtw_op;
348 mips32_insn.fp0_format.opcode = cop1_op;
349 mips32_insn.fp0_format.fmt =
350 sd_format[insn.mm_fp1_format.fmt];
351 mips32_insn.fp0_format.ft = 0;
352 mips32_insn.fp0_format.fs =
353 insn.mm_fp1_format.fs;
354 mips32_insn.fp0_format.fd =
355 insn.mm_fp1_format.rt;
356 mips32_insn.fp0_format.func = func;
357 break;
358 case mm_frsqrt_op:
359 case mm_fsqrt_op:
360 case mm_frecip_op:
361 if (insn.mm_fp1_format.op == mm_frsqrt_op)
362 func = frsqrt_op;
363 else if (insn.mm_fp1_format.op == mm_fsqrt_op)
364 func = fsqrt_op;
365 else
366 func = frecip_op;
367 mips32_insn.fp0_format.opcode = cop1_op;
368 mips32_insn.fp0_format.fmt =
369 sdps_format[insn.mm_fp1_format.fmt];
370 mips32_insn.fp0_format.ft = 0;
371 mips32_insn.fp0_format.fs =
372 insn.mm_fp1_format.fs;
373 mips32_insn.fp0_format.fd =
374 insn.mm_fp1_format.rt;
375 mips32_insn.fp0_format.func = func;
376 break;
377 case mm_mfc1_op:
378 case mm_mtc1_op:
379 case mm_cfc1_op:
380 case mm_ctc1_op:
381 case mm_mfhc1_op:
382 case mm_mthc1_op:
383 if (insn.mm_fp1_format.op == mm_mfc1_op)
384 op = mfc_op;
385 else if (insn.mm_fp1_format.op == mm_mtc1_op)
386 op = mtc_op;
387 else if (insn.mm_fp1_format.op == mm_cfc1_op)
388 op = cfc_op;
389 else if (insn.mm_fp1_format.op == mm_ctc1_op)
390 op = ctc_op;
391 else if (insn.mm_fp1_format.op == mm_mfhc1_op)
392 op = mfhc_op;
393 else
394 op = mthc_op;
395 mips32_insn.fp1_format.opcode = cop1_op;
396 mips32_insn.fp1_format.op = op;
397 mips32_insn.fp1_format.rt =
398 insn.mm_fp1_format.rt;
399 mips32_insn.fp1_format.fs =
400 insn.mm_fp1_format.fs;
401 mips32_insn.fp1_format.fd = 0;
402 mips32_insn.fp1_format.func = 0;
403 break;
404 default:
405 return SIGILL;
406 }
407 break;
408 case mm_32f_74_op: /* c.cond.fmt */
409 mips32_insn.fp0_format.opcode = cop1_op;
410 mips32_insn.fp0_format.fmt =
411 sdps_format[insn.mm_fp4_format.fmt];
412 mips32_insn.fp0_format.ft = insn.mm_fp4_format.rt;
413 mips32_insn.fp0_format.fs = insn.mm_fp4_format.fs;
414 mips32_insn.fp0_format.fd = insn.mm_fp4_format.cc << 2;
415 mips32_insn.fp0_format.func =
416 insn.mm_fp4_format.cond | MM_MIPS32_COND_FC;
417 break;
418 default:
419 return SIGILL;
420 }
421 break;
422 default:
423 return SIGILL;
424 }
425
426 *insn_ptr = mips32_insn;
427 return 0;
428}
429
430/*
431 * Redundant with logic already in kernel/branch.c,
432 * embedded in compute_return_epc. At some point,
433 * a single subroutine should be used across both
434 * modules.
435 */
436int isBranchInstr(struct pt_regs *regs, struct mm_decoded_insn dec_insn,
437 unsigned long *contpc)
438{
439 union mips_instruction insn = (union mips_instruction)dec_insn.insn;
440 unsigned int fcr31;
441 unsigned int bit = 0;
442 unsigned int bit0;
443 union fpureg *fpr;
444
445 switch (insn.i_format.opcode) {
446 case spec_op:
447 switch (insn.r_format.func) {
448 case jalr_op:
449 if (insn.r_format.rd != 0) {
450 regs->regs[insn.r_format.rd] =
451 regs->cp0_epc + dec_insn.pc_inc +
452 dec_insn.next_pc_inc;
453 }
454 /* fall through */
455 case jr_op:
456 /* For R6, JR already emulated in jalr_op */
457 if (NO_R6EMU && insn.r_format.func == jr_op)
458 break;
459 *contpc = regs->regs[insn.r_format.rs];
460 return 1;
461 }
462 break;
463 case bcond_op:
464 switch (insn.i_format.rt) {
465 case bltzal_op:
466 case bltzall_op:
467 if (NO_R6EMU && (insn.i_format.rs ||
468 insn.i_format.rt == bltzall_op))
469 break;
470
471 regs->regs[31] = regs->cp0_epc +
472 dec_insn.pc_inc +
473 dec_insn.next_pc_inc;
474 /* fall through */
475 case bltzl_op:
476 if (NO_R6EMU)
477 break;
478 /* fall through */
479 case bltz_op:
480 if ((long)regs->regs[insn.i_format.rs] < 0)
481 *contpc = regs->cp0_epc +
482 dec_insn.pc_inc +
483 (insn.i_format.simmediate << 2);
484 else
485 *contpc = regs->cp0_epc +
486 dec_insn.pc_inc +
487 dec_insn.next_pc_inc;
488 return 1;
489 case bgezal_op:
490 case bgezall_op:
491 if (NO_R6EMU && (insn.i_format.rs ||
492 insn.i_format.rt == bgezall_op))
493 break;
494
495 regs->regs[31] = regs->cp0_epc +
496 dec_insn.pc_inc +
497 dec_insn.next_pc_inc;
498 /* fall through */
499 case bgezl_op:
500 if (NO_R6EMU)
501 break;
502 /* fall through */
503 case bgez_op:
504 if ((long)regs->regs[insn.i_format.rs] >= 0)
505 *contpc = regs->cp0_epc +
506 dec_insn.pc_inc +
507 (insn.i_format.simmediate << 2);
508 else
509 *contpc = regs->cp0_epc +
510 dec_insn.pc_inc +
511 dec_insn.next_pc_inc;
512 return 1;
513 }
514 break;
515 case jalx_op:
516 set_isa16_mode(bit);
517 /* fall through */
518 case jal_op:
519 regs->regs[31] = regs->cp0_epc +
520 dec_insn.pc_inc +
521 dec_insn.next_pc_inc;
522 /* fall through */
523 case j_op:
524 *contpc = regs->cp0_epc + dec_insn.pc_inc;
525 *contpc >>= 28;
526 *contpc <<= 28;
527 *contpc |= (insn.j_format.target << 2);
528 /* Set microMIPS mode bit: XOR for jalx. */
529 *contpc ^= bit;
530 return 1;
531 case beql_op:
532 if (NO_R6EMU)
533 break;
534 /* fall through */
535 case beq_op:
536 if (regs->regs[insn.i_format.rs] ==
537 regs->regs[insn.i_format.rt])
538 *contpc = regs->cp0_epc +
539 dec_insn.pc_inc +
540 (insn.i_format.simmediate << 2);
541 else
542 *contpc = regs->cp0_epc +
543 dec_insn.pc_inc +
544 dec_insn.next_pc_inc;
545 return 1;
546 case bnel_op:
547 if (NO_R6EMU)
548 break;
549 /* fall through */
550 case bne_op:
551 if (regs->regs[insn.i_format.rs] !=
552 regs->regs[insn.i_format.rt])
553 *contpc = regs->cp0_epc +
554 dec_insn.pc_inc +
555 (insn.i_format.simmediate << 2);
556 else
557 *contpc = regs->cp0_epc +
558 dec_insn.pc_inc +
559 dec_insn.next_pc_inc;
560 return 1;
561 case blezl_op:
562 if (!insn.i_format.rt && NO_R6EMU)
563 break;
564 /* fall through */
565 case blez_op:
566
567 /*
568 * Compact branches for R6 for the
569 * blez and blezl opcodes.
570 * BLEZ | rs = 0 | rt != 0 == BLEZALC
571 * BLEZ | rs = rt != 0 == BGEZALC
572 * BLEZ | rs != 0 | rt != 0 == BGEUC
573 * BLEZL | rs = 0 | rt != 0 == BLEZC
574 * BLEZL | rs = rt != 0 == BGEZC
575 * BLEZL | rs != 0 | rt != 0 == BGEC
576 *
577 * For real BLEZ{,L}, rt is always 0.
578 */
579 if (cpu_has_mips_r6 && insn.i_format.rt) {
580 if ((insn.i_format.opcode == blez_op) &&
581 ((!insn.i_format.rs && insn.i_format.rt) ||
582 (insn.i_format.rs == insn.i_format.rt)))
583 regs->regs[31] = regs->cp0_epc +
584 dec_insn.pc_inc;
585 *contpc = regs->cp0_epc + dec_insn.pc_inc +
586 dec_insn.next_pc_inc;
587
588 return 1;
589 }
590 if ((long)regs->regs[insn.i_format.rs] <= 0)
591 *contpc = regs->cp0_epc +
592 dec_insn.pc_inc +
593 (insn.i_format.simmediate << 2);
594 else
595 *contpc = regs->cp0_epc +
596 dec_insn.pc_inc +
597 dec_insn.next_pc_inc;
598 return 1;
599 case bgtzl_op:
600 if (!insn.i_format.rt && NO_R6EMU)
601 break;
602 /* fall through */
603 case bgtz_op:
604 /*
605 * Compact branches for R6 for the
606 * bgtz and bgtzl opcodes.
607 * BGTZ | rs = 0 | rt != 0 == BGTZALC
608 * BGTZ | rs = rt != 0 == BLTZALC
609 * BGTZ | rs != 0 | rt != 0 == BLTUC
610 * BGTZL | rs = 0 | rt != 0 == BGTZC
611 * BGTZL | rs = rt != 0 == BLTZC
612 * BGTZL | rs != 0 | rt != 0 == BLTC
613 *
614 * *ZALC varint for BGTZ &&& rt != 0
615 * For real GTZ{,L}, rt is always 0.
616 */
617 if (cpu_has_mips_r6 && insn.i_format.rt) {
618 if ((insn.i_format.opcode == blez_op) &&
619 ((!insn.i_format.rs && insn.i_format.rt) ||
620 (insn.i_format.rs == insn.i_format.rt)))
621 regs->regs[31] = regs->cp0_epc +
622 dec_insn.pc_inc;
623 *contpc = regs->cp0_epc + dec_insn.pc_inc +
624 dec_insn.next_pc_inc;
625
626 return 1;
627 }
628
629 if ((long)regs->regs[insn.i_format.rs] > 0)
630 *contpc = regs->cp0_epc +
631 dec_insn.pc_inc +
632 (insn.i_format.simmediate << 2);
633 else
634 *contpc = regs->cp0_epc +
635 dec_insn.pc_inc +
636 dec_insn.next_pc_inc;
637 return 1;
638 case pop10_op:
639 case pop30_op:
640 if (!cpu_has_mips_r6)
641 break;
642 if (insn.i_format.rt && !insn.i_format.rs)
643 regs->regs[31] = regs->cp0_epc + 4;
644 *contpc = regs->cp0_epc + dec_insn.pc_inc +
645 dec_insn.next_pc_inc;
646
647 return 1;
648#ifdef CONFIG_CPU_CAVIUM_OCTEON
649 case lwc2_op: /* This is bbit0 on Octeon */
650 if ((regs->regs[insn.i_format.rs] & (1ull<<insn.i_format.rt)) == 0)
651 *contpc = regs->cp0_epc + 4 + (insn.i_format.simmediate << 2);
652 else
653 *contpc = regs->cp0_epc + 8;
654 return 1;
655 case ldc2_op: /* This is bbit032 on Octeon */
656 if ((regs->regs[insn.i_format.rs] & (1ull<<(insn.i_format.rt + 32))) == 0)
657 *contpc = regs->cp0_epc + 4 + (insn.i_format.simmediate << 2);
658 else
659 *contpc = regs->cp0_epc + 8;
660 return 1;
661 case swc2_op: /* This is bbit1 on Octeon */
662 if (regs->regs[insn.i_format.rs] & (1ull<<insn.i_format.rt))
663 *contpc = regs->cp0_epc + 4 + (insn.i_format.simmediate << 2);
664 else
665 *contpc = regs->cp0_epc + 8;
666 return 1;
667 case sdc2_op: /* This is bbit132 on Octeon */
668 if (regs->regs[insn.i_format.rs] & (1ull<<(insn.i_format.rt + 32)))
669 *contpc = regs->cp0_epc + 4 + (insn.i_format.simmediate << 2);
670 else
671 *contpc = regs->cp0_epc + 8;
672 return 1;
673#else
674 case bc6_op:
675 /*
676 * Only valid for MIPS R6 but we can still end up
677 * here from a broken userland so just tell emulator
678 * this is not a branch and let it break later on.
679 */
680 if (!cpu_has_mips_r6)
681 break;
682 *contpc = regs->cp0_epc + dec_insn.pc_inc +
683 dec_insn.next_pc_inc;
684
685 return 1;
686 case balc6_op:
687 if (!cpu_has_mips_r6)
688 break;
689 regs->regs[31] = regs->cp0_epc + 4;
690 *contpc = regs->cp0_epc + dec_insn.pc_inc +
691 dec_insn.next_pc_inc;
692
693 return 1;
694 case pop66_op:
695 if (!cpu_has_mips_r6)
696 break;
697 *contpc = regs->cp0_epc + dec_insn.pc_inc +
698 dec_insn.next_pc_inc;
699
700 return 1;
701 case pop76_op:
702 if (!cpu_has_mips_r6)
703 break;
704 if (!insn.i_format.rs)
705 regs->regs[31] = regs->cp0_epc + 4;
706 *contpc = regs->cp0_epc + dec_insn.pc_inc +
707 dec_insn.next_pc_inc;
708
709 return 1;
710#endif
711 case cop0_op:
712 case cop1_op:
713 /* Need to check for R6 bc1nez and bc1eqz branches */
714 if (cpu_has_mips_r6 &&
715 ((insn.i_format.rs == bc1eqz_op) ||
716 (insn.i_format.rs == bc1nez_op))) {
717 bit = 0;
718 fpr = ¤t->thread.fpu.fpr[insn.i_format.rt];
719 bit0 = get_fpr32(fpr, 0) & 0x1;
720 switch (insn.i_format.rs) {
721 case bc1eqz_op:
722 bit = bit0 == 0;
723 break;
724 case bc1nez_op:
725 bit = bit0 != 0;
726 break;
727 }
728 if (bit)
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
737 return 1;
738 }
739 /* R2/R6 compatible cop1 instruction */
740 /* fall through */
741 case cop2_op:
742 case cop1x_op:
743 if (insn.i_format.rs == bc_op) {
744 preempt_disable();
745 if (is_fpu_owner())
746 fcr31 = read_32bit_cp1_register(CP1_STATUS);
747 else
748 fcr31 = current->thread.fpu.fcr31;
749 preempt_enable();
750
751 bit = (insn.i_format.rt >> 2);
752 bit += (bit != 0);
753 bit += 23;
754 switch (insn.i_format.rt & 3) {
755 case 0: /* bc1f */
756 case 2: /* bc1fl */
757 if (~fcr31 & (1 << bit))
758 *contpc = regs->cp0_epc +
759 dec_insn.pc_inc +
760 (insn.i_format.simmediate << 2);
761 else
762 *contpc = regs->cp0_epc +
763 dec_insn.pc_inc +
764 dec_insn.next_pc_inc;
765 return 1;
766 case 1: /* bc1t */
767 case 3: /* bc1tl */
768 if (fcr31 & (1 << bit))
769 *contpc = regs->cp0_epc +
770 dec_insn.pc_inc +
771 (insn.i_format.simmediate << 2);
772 else
773 *contpc = regs->cp0_epc +
774 dec_insn.pc_inc +
775 dec_insn.next_pc_inc;
776 return 1;
777 }
778 }
779 break;
780 }
781 return 0;
782}
783
784/*
785 * In the Linux kernel, we support selection of FPR format on the
786 * basis of the Status.FR bit. If an FPU is not present, the FR bit
787 * is hardwired to zero, which would imply a 32-bit FPU even for
788 * 64-bit CPUs so we rather look at TIF_32BIT_FPREGS.
789 * FPU emu is slow and bulky and optimizing this function offers fairly
790 * sizeable benefits so we try to be clever and make this function return
791 * a constant whenever possible, that is on 64-bit kernels without O32
792 * compatibility enabled and on 32-bit without 64-bit FPU support.
793 */
794static inline int cop1_64bit(struct pt_regs *xcp)
795{
796 if (IS_ENABLED(CONFIG_64BIT) && !IS_ENABLED(CONFIG_MIPS32_O32))
797 return 1;
798 else if (IS_ENABLED(CONFIG_32BIT) &&
799 !IS_ENABLED(CONFIG_MIPS_O32_FP64_SUPPORT))
800 return 0;
801
802 return !test_thread_flag(TIF_32BIT_FPREGS);
803}
804
805static inline bool hybrid_fprs(void)
806{
807 return test_thread_flag(TIF_HYBRID_FPREGS);
808}
809
810#define SIFROMREG(si, x) \
811do { \
812 if (cop1_64bit(xcp) && !hybrid_fprs()) \
813 (si) = (int)get_fpr32(&ctx->fpr[x], 0); \
814 else \
815 (si) = (int)get_fpr32(&ctx->fpr[(x) & ~1], (x) & 1); \
816} while (0)
817
818#define SITOREG(si, x) \
819do { \
820 if (cop1_64bit(xcp) && !hybrid_fprs()) { \
821 unsigned int i; \
822 set_fpr32(&ctx->fpr[x], 0, si); \
823 for (i = 1; i < ARRAY_SIZE(ctx->fpr[x].val32); i++) \
824 set_fpr32(&ctx->fpr[x], i, 0); \
825 } else { \
826 set_fpr32(&ctx->fpr[(x) & ~1], (x) & 1, si); \
827 } \
828} while (0)
829
830#define SIFROMHREG(si, x) ((si) = (int)get_fpr32(&ctx->fpr[x], 1))
831
832#define SITOHREG(si, x) \
833do { \
834 unsigned int i; \
835 set_fpr32(&ctx->fpr[x], 1, si); \
836 for (i = 2; i < ARRAY_SIZE(ctx->fpr[x].val32); i++) \
837 set_fpr32(&ctx->fpr[x], i, 0); \
838} while (0)
839
840#define DIFROMREG(di, x) \
841 ((di) = get_fpr64(&ctx->fpr[(x) & ~(cop1_64bit(xcp) ^ 1)], 0))
842
843#define DITOREG(di, x) \
844do { \
845 unsigned int fpr, i; \
846 fpr = (x) & ~(cop1_64bit(xcp) ^ 1); \
847 set_fpr64(&ctx->fpr[fpr], 0, di); \
848 for (i = 1; i < ARRAY_SIZE(ctx->fpr[x].val64); i++) \
849 set_fpr64(&ctx->fpr[fpr], i, 0); \
850} while (0)
851
852#define SPFROMREG(sp, x) SIFROMREG((sp).bits, x)
853#define SPTOREG(sp, x) SITOREG((sp).bits, x)
854#define DPFROMREG(dp, x) DIFROMREG((dp).bits, x)
855#define DPTOREG(dp, x) DITOREG((dp).bits, x)
856
857/*
858 * Emulate a CFC1 instruction.
859 */
860static inline void cop1_cfc(struct pt_regs *xcp, struct mips_fpu_struct *ctx,
861 mips_instruction ir)
862{
863 u32 fcr31 = ctx->fcr31;
864 u32 value = 0;
865
866 switch (MIPSInst_RD(ir)) {
867 case FPCREG_CSR:
868 value = fcr31;
869 pr_debug("%p gpr[%d]<-csr=%08x\n",
870 (void *)xcp->cp0_epc, MIPSInst_RT(ir), value);
871 break;
872
873 case FPCREG_FENR:
874 if (!cpu_has_mips_r)
875 break;
876 value = (fcr31 >> (FPU_CSR_FS_S - MIPS_FENR_FS_S)) &
877 MIPS_FENR_FS;
878 value |= fcr31 & (FPU_CSR_ALL_E | FPU_CSR_RM);
879 pr_debug("%p gpr[%d]<-enr=%08x\n",
880 (void *)xcp->cp0_epc, MIPSInst_RT(ir), value);
881 break;
882
883 case FPCREG_FEXR:
884 if (!cpu_has_mips_r)
885 break;
886 value = fcr31 & (FPU_CSR_ALL_X | FPU_CSR_ALL_S);
887 pr_debug("%p gpr[%d]<-exr=%08x\n",
888 (void *)xcp->cp0_epc, MIPSInst_RT(ir), value);
889 break;
890
891 case FPCREG_FCCR:
892 if (!cpu_has_mips_r)
893 break;
894 value = (fcr31 >> (FPU_CSR_COND_S - MIPS_FCCR_COND0_S)) &
895 MIPS_FCCR_COND0;
896 value |= (fcr31 >> (FPU_CSR_COND1_S - MIPS_FCCR_COND1_S)) &
897 (MIPS_FCCR_CONDX & ~MIPS_FCCR_COND0);
898 pr_debug("%p gpr[%d]<-ccr=%08x\n",
899 (void *)xcp->cp0_epc, MIPSInst_RT(ir), value);
900 break;
901
902 case FPCREG_RID:
903 value = boot_cpu_data.fpu_id;
904 break;
905
906 default:
907 break;
908 }
909
910 if (MIPSInst_RT(ir))
911 xcp->regs[MIPSInst_RT(ir)] = value;
912}
913
914/*
915 * Emulate a CTC1 instruction.
916 */
917static inline void cop1_ctc(struct pt_regs *xcp, struct mips_fpu_struct *ctx,
918 mips_instruction ir)
919{
920 u32 fcr31 = ctx->fcr31;
921 u32 value;
922 u32 mask;
923
924 if (MIPSInst_RT(ir) == 0)
925 value = 0;
926 else
927 value = xcp->regs[MIPSInst_RT(ir)];
928
929 switch (MIPSInst_RD(ir)) {
930 case FPCREG_CSR:
931 pr_debug("%p gpr[%d]->csr=%08x\n",
932 (void *)xcp->cp0_epc, MIPSInst_RT(ir), value);
933
934 /* Preserve read-only bits. */
935 mask = boot_cpu_data.fpu_msk31;
936 fcr31 = (value & ~mask) | (fcr31 & mask);
937 break;
938
939 case FPCREG_FENR:
940 if (!cpu_has_mips_r)
941 break;
942 pr_debug("%p gpr[%d]->enr=%08x\n",
943 (void *)xcp->cp0_epc, MIPSInst_RT(ir), value);
944 fcr31 &= ~(FPU_CSR_FS | FPU_CSR_ALL_E | FPU_CSR_RM);
945 fcr31 |= (value << (FPU_CSR_FS_S - MIPS_FENR_FS_S)) &
946 FPU_CSR_FS;
947 fcr31 |= value & (FPU_CSR_ALL_E | FPU_CSR_RM);
948 break;
949
950 case FPCREG_FEXR:
951 if (!cpu_has_mips_r)
952 break;
953 pr_debug("%p gpr[%d]->exr=%08x\n",
954 (void *)xcp->cp0_epc, MIPSInst_RT(ir), value);
955 fcr31 &= ~(FPU_CSR_ALL_X | FPU_CSR_ALL_S);
956 fcr31 |= value & (FPU_CSR_ALL_X | FPU_CSR_ALL_S);
957 break;
958
959 case FPCREG_FCCR:
960 if (!cpu_has_mips_r)
961 break;
962 pr_debug("%p gpr[%d]->ccr=%08x\n",
963 (void *)xcp->cp0_epc, MIPSInst_RT(ir), value);
964 fcr31 &= ~(FPU_CSR_CONDX | FPU_CSR_COND);
965 fcr31 |= (value << (FPU_CSR_COND_S - MIPS_FCCR_COND0_S)) &
966 FPU_CSR_COND;
967 fcr31 |= (value << (FPU_CSR_COND1_S - MIPS_FCCR_COND1_S)) &
968 FPU_CSR_CONDX;
969 break;
970
971 default:
972 break;
973 }
974
975 ctx->fcr31 = fcr31;
976}
977
978/*
979 * Emulate the single floating point instruction pointed at by EPC.
980 * Two instructions if the instruction is in a branch delay slot.
981 */
982
983static int cop1Emulate(struct pt_regs *xcp, struct mips_fpu_struct *ctx,
984 struct mm_decoded_insn dec_insn, void __user **fault_addr)
985{
986 unsigned long contpc = xcp->cp0_epc + dec_insn.pc_inc;
987 unsigned int cond, cbit, bit0;
988 mips_instruction ir;
989 int likely, pc_inc;
990 union fpureg *fpr;
991 u32 __user *wva;
992 u64 __user *dva;
993 u32 wval;
994 u64 dval;
995 int sig;
996
997 /*
998 * These are giving gcc a gentle hint about what to expect in
999 * dec_inst in order to do better optimization.
1000 */
1001 if (!cpu_has_mmips && dec_insn.micro_mips_mode)
1002 unreachable();
1003
1004 /* XXX NEC Vr54xx bug workaround */
1005 if (delay_slot(xcp)) {
1006 if (dec_insn.micro_mips_mode) {
1007 if (!mm_isBranchInstr(xcp, dec_insn, &contpc))
1008 clear_delay_slot(xcp);
1009 } else {
1010 if (!isBranchInstr(xcp, dec_insn, &contpc))
1011 clear_delay_slot(xcp);
1012 }
1013 }
1014
1015 if (delay_slot(xcp)) {
1016 /*
1017 * The instruction to be emulated is in a branch delay slot
1018 * which means that we have to emulate the branch instruction
1019 * BEFORE we do the cop1 instruction.
1020 *
1021 * This branch could be a COP1 branch, but in that case we
1022 * would have had a trap for that instruction, and would not
1023 * come through this route.
1024 *
1025 * Linux MIPS branch emulator operates on context, updating the
1026 * cp0_epc.
1027 */
1028 ir = dec_insn.next_insn; /* process delay slot instr */
1029 pc_inc = dec_insn.next_pc_inc;
1030 } else {
1031 ir = dec_insn.insn; /* process current instr */
1032 pc_inc = dec_insn.pc_inc;
1033 }
1034
1035 /*
1036 * Since microMIPS FPU instructios are a subset of MIPS32 FPU
1037 * instructions, we want to convert microMIPS FPU instructions
1038 * into MIPS32 instructions so that we could reuse all of the
1039 * FPU emulation code.
1040 *
1041 * NOTE: We cannot do this for branch instructions since they
1042 * are not a subset. Example: Cannot emulate a 16-bit
1043 * aligned target address with a MIPS32 instruction.
1044 */
1045 if (dec_insn.micro_mips_mode) {
1046 /*
1047 * If next instruction is a 16-bit instruction, then it
1048 * it cannot be a FPU instruction. This could happen
1049 * since we can be called for non-FPU instructions.
1050 */
1051 if ((pc_inc == 2) ||
1052 (microMIPS32_to_MIPS32((union mips_instruction *)&ir)
1053 == SIGILL))
1054 return SIGILL;
1055 }
1056
1057emul:
1058 perf_sw_event(PERF_COUNT_SW_EMULATION_FAULTS, 1, xcp, 0);
1059 MIPS_FPU_EMU_INC_STATS(emulated);
1060 switch (MIPSInst_OPCODE(ir)) {
1061 case ldc1_op:
1062 dva = (u64 __user *) (xcp->regs[MIPSInst_RS(ir)] +
1063 MIPSInst_SIMM(ir));
1064 MIPS_FPU_EMU_INC_STATS(loads);
1065
1066 if (!access_ok(VERIFY_READ, dva, sizeof(u64))) {
1067 MIPS_FPU_EMU_INC_STATS(errors);
1068 *fault_addr = dva;
1069 return SIGBUS;
1070 }
1071 if (__get_user(dval, dva)) {
1072 MIPS_FPU_EMU_INC_STATS(errors);
1073 *fault_addr = dva;
1074 return SIGSEGV;
1075 }
1076 DITOREG(dval, MIPSInst_RT(ir));
1077 break;
1078
1079 case sdc1_op:
1080 dva = (u64 __user *) (xcp->regs[MIPSInst_RS(ir)] +
1081 MIPSInst_SIMM(ir));
1082 MIPS_FPU_EMU_INC_STATS(stores);
1083 DIFROMREG(dval, MIPSInst_RT(ir));
1084 if (!access_ok(VERIFY_WRITE, dva, sizeof(u64))) {
1085 MIPS_FPU_EMU_INC_STATS(errors);
1086 *fault_addr = dva;
1087 return SIGBUS;
1088 }
1089 if (__put_user(dval, dva)) {
1090 MIPS_FPU_EMU_INC_STATS(errors);
1091 *fault_addr = dva;
1092 return SIGSEGV;
1093 }
1094 break;
1095
1096 case lwc1_op:
1097 wva = (u32 __user *) (xcp->regs[MIPSInst_RS(ir)] +
1098 MIPSInst_SIMM(ir));
1099 MIPS_FPU_EMU_INC_STATS(loads);
1100 if (!access_ok(VERIFY_READ, wva, sizeof(u32))) {
1101 MIPS_FPU_EMU_INC_STATS(errors);
1102 *fault_addr = wva;
1103 return SIGBUS;
1104 }
1105 if (__get_user(wval, wva)) {
1106 MIPS_FPU_EMU_INC_STATS(errors);
1107 *fault_addr = wva;
1108 return SIGSEGV;
1109 }
1110 SITOREG(wval, MIPSInst_RT(ir));
1111 break;
1112
1113 case swc1_op:
1114 wva = (u32 __user *) (xcp->regs[MIPSInst_RS(ir)] +
1115 MIPSInst_SIMM(ir));
1116 MIPS_FPU_EMU_INC_STATS(stores);
1117 SIFROMREG(wval, MIPSInst_RT(ir));
1118 if (!access_ok(VERIFY_WRITE, wva, sizeof(u32))) {
1119 MIPS_FPU_EMU_INC_STATS(errors);
1120 *fault_addr = wva;
1121 return SIGBUS;
1122 }
1123 if (__put_user(wval, wva)) {
1124 MIPS_FPU_EMU_INC_STATS(errors);
1125 *fault_addr = wva;
1126 return SIGSEGV;
1127 }
1128 break;
1129
1130 case cop1_op:
1131 switch (MIPSInst_RS(ir)) {
1132 case dmfc_op:
1133 if (!cpu_has_mips_3_4_5 && !cpu_has_mips64)
1134 return SIGILL;
1135
1136 /* copregister fs -> gpr[rt] */
1137 if (MIPSInst_RT(ir) != 0) {
1138 DIFROMREG(xcp->regs[MIPSInst_RT(ir)],
1139 MIPSInst_RD(ir));
1140 }
1141 break;
1142
1143 case dmtc_op:
1144 if (!cpu_has_mips_3_4_5 && !cpu_has_mips64)
1145 return SIGILL;
1146
1147 /* copregister fs <- rt */
1148 DITOREG(xcp->regs[MIPSInst_RT(ir)], MIPSInst_RD(ir));
1149 break;
1150
1151 case mfhc_op:
1152 if (!cpu_has_mips_r2_r6)
1153 return SIGILL;
1154
1155 /* copregister rd -> gpr[rt] */
1156 if (MIPSInst_RT(ir) != 0) {
1157 SIFROMHREG(xcp->regs[MIPSInst_RT(ir)],
1158 MIPSInst_RD(ir));
1159 }
1160 break;
1161
1162 case mthc_op:
1163 if (!cpu_has_mips_r2_r6)
1164 return SIGILL;
1165
1166 /* copregister rd <- gpr[rt] */
1167 SITOHREG(xcp->regs[MIPSInst_RT(ir)], MIPSInst_RD(ir));
1168 break;
1169
1170 case mfc_op:
1171 /* copregister rd -> gpr[rt] */
1172 if (MIPSInst_RT(ir) != 0) {
1173 SIFROMREG(xcp->regs[MIPSInst_RT(ir)],
1174 MIPSInst_RD(ir));
1175 }
1176 break;
1177
1178 case mtc_op:
1179 /* copregister rd <- rt */
1180 SITOREG(xcp->regs[MIPSInst_RT(ir)], MIPSInst_RD(ir));
1181 break;
1182
1183 case cfc_op:
1184 /* cop control register rd -> gpr[rt] */
1185 cop1_cfc(xcp, ctx, ir);
1186 break;
1187
1188 case ctc_op:
1189 /* copregister rd <- rt */
1190 cop1_ctc(xcp, ctx, ir);
1191 if ((ctx->fcr31 >> 5) & ctx->fcr31 & FPU_CSR_ALL_E) {
1192 return SIGFPE;
1193 }
1194 break;
1195
1196 case bc1eqz_op:
1197 case bc1nez_op:
1198 if (!cpu_has_mips_r6 || delay_slot(xcp))
1199 return SIGILL;
1200
1201 likely = 0;
1202 cond = 0;
1203 fpr = ¤t->thread.fpu.fpr[MIPSInst_RT(ir)];
1204 bit0 = get_fpr32(fpr, 0) & 0x1;
1205 switch (MIPSInst_RS(ir)) {
1206 case bc1eqz_op:
1207 MIPS_FPU_EMU_INC_STATS(bc1eqz);
1208 cond = bit0 == 0;
1209 break;
1210 case bc1nez_op:
1211 MIPS_FPU_EMU_INC_STATS(bc1nez);
1212 cond = bit0 != 0;
1213 break;
1214 }
1215 goto branch_common;
1216
1217 case bc_op:
1218 if (delay_slot(xcp))
1219 return SIGILL;
1220
1221 if (cpu_has_mips_4_5_r)
1222 cbit = fpucondbit[MIPSInst_RT(ir) >> 2];
1223 else
1224 cbit = FPU_CSR_COND;
1225 cond = ctx->fcr31 & cbit;
1226
1227 likely = 0;
1228 switch (MIPSInst_RT(ir) & 3) {
1229 case bcfl_op:
1230 if (cpu_has_mips_2_3_4_5_r)
1231 likely = 1;
1232 /* fall through */
1233 case bcf_op:
1234 cond = !cond;
1235 break;
1236 case bctl_op:
1237 if (cpu_has_mips_2_3_4_5_r)
1238 likely = 1;
1239 /* fall through */
1240 case bct_op:
1241 break;
1242 }
1243branch_common:
1244 MIPS_FPU_EMU_INC_STATS(branches);
1245 set_delay_slot(xcp);
1246 if (cond) {
1247 /*
1248 * Branch taken: emulate dslot instruction
1249 */
1250 unsigned long bcpc;
1251
1252 /*
1253 * Remember EPC at the branch to point back
1254 * at so that any delay-slot instruction
1255 * signal is not silently ignored.
1256 */
1257 bcpc = xcp->cp0_epc;
1258 xcp->cp0_epc += dec_insn.pc_inc;
1259
1260 contpc = MIPSInst_SIMM(ir);
1261 ir = dec_insn.next_insn;
1262 if (dec_insn.micro_mips_mode) {
1263 contpc = (xcp->cp0_epc + (contpc << 1));
1264
1265 /* If 16-bit instruction, not FPU. */
1266 if ((dec_insn.next_pc_inc == 2) ||
1267 (microMIPS32_to_MIPS32((union mips_instruction *)&ir) == SIGILL)) {
1268
1269 /*
1270 * Since this instruction will
1271 * be put on the stack with
1272 * 32-bit words, get around
1273 * this problem by putting a
1274 * NOP16 as the second one.
1275 */
1276 if (dec_insn.next_pc_inc == 2)
1277 ir = (ir & (~0xffff)) | MM_NOP16;
1278
1279 /*
1280 * Single step the non-CP1
1281 * instruction in the dslot.
1282 */
1283 sig = mips_dsemul(xcp, ir,
1284 bcpc, contpc);
1285 if (sig < 0)
1286 break;
1287 if (sig)
1288 xcp->cp0_epc = bcpc;
1289 /*
1290 * SIGILL forces out of
1291 * the emulation loop.
1292 */
1293 return sig ? sig : SIGILL;
1294 }
1295 } else
1296 contpc = (xcp->cp0_epc + (contpc << 2));
1297
1298 switch (MIPSInst_OPCODE(ir)) {
1299 case lwc1_op:
1300 case swc1_op:
1301 goto emul;
1302
1303 case ldc1_op:
1304 case sdc1_op:
1305 if (cpu_has_mips_2_3_4_5_r)
1306 goto emul;
1307
1308 goto bc_sigill;
1309
1310 case cop1_op:
1311 goto emul;
1312
1313 case cop1x_op:
1314 if (cpu_has_mips_4_5_64_r2_r6)
1315 /* its one of ours */
1316 goto emul;
1317
1318 goto bc_sigill;
1319
1320 case spec_op:
1321 switch (MIPSInst_FUNC(ir)) {
1322 case movc_op:
1323 if (cpu_has_mips_4_5_r)
1324 goto emul;
1325
1326 goto bc_sigill;
1327 }
1328 break;
1329
1330 bc_sigill:
1331 xcp->cp0_epc = bcpc;
1332 return SIGILL;
1333 }
1334
1335 /*
1336 * Single step the non-cp1
1337 * instruction in the dslot
1338 */
1339 sig = mips_dsemul(xcp, ir, bcpc, contpc);
1340 if (sig < 0)
1341 break;
1342 if (sig)
1343 xcp->cp0_epc = bcpc;
1344 /* SIGILL forces out of the emulation loop. */
1345 return sig ? sig : SIGILL;
1346 } else if (likely) { /* branch not taken */
1347 /*
1348 * branch likely nullifies
1349 * dslot if not taken
1350 */
1351 xcp->cp0_epc += dec_insn.pc_inc;
1352 contpc += dec_insn.pc_inc;
1353 /*
1354 * else continue & execute
1355 * dslot as normal insn
1356 */
1357 }
1358 break;
1359
1360 default:
1361 if (!(MIPSInst_RS(ir) & 0x10))
1362 return SIGILL;
1363
1364 /* a real fpu computation instruction */
1365 sig = fpu_emu(xcp, ctx, ir);
1366 if (sig)
1367 return sig;
1368 }
1369 break;
1370
1371 case cop1x_op:
1372 if (!cpu_has_mips_4_5_64_r2_r6)
1373 return SIGILL;
1374
1375 sig = fpux_emu(xcp, ctx, ir, fault_addr);
1376 if (sig)
1377 return sig;
1378 break;
1379
1380 case spec_op:
1381 if (!cpu_has_mips_4_5_r)
1382 return SIGILL;
1383
1384 if (MIPSInst_FUNC(ir) != movc_op)
1385 return SIGILL;
1386 cond = fpucondbit[MIPSInst_RT(ir) >> 2];
1387 if (((ctx->fcr31 & cond) != 0) == ((MIPSInst_RT(ir) & 1) != 0))
1388 xcp->regs[MIPSInst_RD(ir)] =
1389 xcp->regs[MIPSInst_RS(ir)];
1390 break;
1391 default:
1392 return SIGILL;
1393 }
1394
1395 /* we did it !! */
1396 xcp->cp0_epc = contpc;
1397 clear_delay_slot(xcp);
1398
1399 return 0;
1400}
1401
1402/*
1403 * Conversion table from MIPS compare ops 48-63
1404 * cond = ieee754dp_cmp(x,y,IEEE754_UN,sig);
1405 */
1406static const unsigned char cmptab[8] = {
1407 0, /* cmp_0 (sig) cmp_sf */
1408 IEEE754_CUN, /* cmp_un (sig) cmp_ngle */
1409 IEEE754_CEQ, /* cmp_eq (sig) cmp_seq */
1410 IEEE754_CEQ | IEEE754_CUN, /* cmp_ueq (sig) cmp_ngl */
1411 IEEE754_CLT, /* cmp_olt (sig) cmp_lt */
1412 IEEE754_CLT | IEEE754_CUN, /* cmp_ult (sig) cmp_nge */
1413 IEEE754_CLT | IEEE754_CEQ, /* cmp_ole (sig) cmp_le */
1414 IEEE754_CLT | IEEE754_CEQ | IEEE754_CUN, /* cmp_ule (sig) cmp_ngt */
1415};
1416
1417static const unsigned char negative_cmptab[8] = {
1418 0, /* Reserved */
1419 IEEE754_CLT | IEEE754_CGT | IEEE754_CEQ,
1420 IEEE754_CLT | IEEE754_CGT | IEEE754_CUN,
1421 IEEE754_CLT | IEEE754_CGT,
1422 /* Reserved */
1423};
1424
1425
1426/*
1427 * Additional MIPS4 instructions
1428 */
1429
1430#define DEF3OP(name, p, f1, f2, f3) \
1431static union ieee754##p fpemu_##p##_##name(union ieee754##p r, \
1432 union ieee754##p s, union ieee754##p t) \
1433{ \
1434 struct _ieee754_csr ieee754_csr_save; \
1435 s = f1(s, t); \
1436 ieee754_csr_save = ieee754_csr; \
1437 s = f2(s, r); \
1438 ieee754_csr_save.cx |= ieee754_csr.cx; \
1439 ieee754_csr_save.sx |= ieee754_csr.sx; \
1440 s = f3(s); \
1441 ieee754_csr.cx |= ieee754_csr_save.cx; \
1442 ieee754_csr.sx |= ieee754_csr_save.sx; \
1443 return s; \
1444}
1445
1446static union ieee754dp fpemu_dp_recip(union ieee754dp d)
1447{
1448 return ieee754dp_div(ieee754dp_one(0), d);
1449}
1450
1451static union ieee754dp fpemu_dp_rsqrt(union ieee754dp d)
1452{
1453 return ieee754dp_div(ieee754dp_one(0), ieee754dp_sqrt(d));
1454}
1455
1456static union ieee754sp fpemu_sp_recip(union ieee754sp s)
1457{
1458 return ieee754sp_div(ieee754sp_one(0), s);
1459}
1460
1461static union ieee754sp fpemu_sp_rsqrt(union ieee754sp s)
1462{
1463 return ieee754sp_div(ieee754sp_one(0), ieee754sp_sqrt(s));
1464}
1465
1466DEF3OP(madd, sp, ieee754sp_mul, ieee754sp_add, );
1467DEF3OP(msub, sp, ieee754sp_mul, ieee754sp_sub, );
1468DEF3OP(nmadd, sp, ieee754sp_mul, ieee754sp_add, ieee754sp_neg);
1469DEF3OP(nmsub, sp, ieee754sp_mul, ieee754sp_sub, ieee754sp_neg);
1470DEF3OP(madd, dp, ieee754dp_mul, ieee754dp_add, );
1471DEF3OP(msub, dp, ieee754dp_mul, ieee754dp_sub, );
1472DEF3OP(nmadd, dp, ieee754dp_mul, ieee754dp_add, ieee754dp_neg);
1473DEF3OP(nmsub, dp, ieee754dp_mul, ieee754dp_sub, ieee754dp_neg);
1474
1475static int fpux_emu(struct pt_regs *xcp, struct mips_fpu_struct *ctx,
1476 mips_instruction ir, void __user **fault_addr)
1477{
1478 unsigned int rcsr = 0; /* resulting csr */
1479
1480 MIPS_FPU_EMU_INC_STATS(cp1xops);
1481
1482 switch (MIPSInst_FMA_FFMT(ir)) {
1483 case s_fmt:{ /* 0 */
1484
1485 union ieee754sp(*handler) (union ieee754sp, union ieee754sp, union ieee754sp);
1486 union ieee754sp fd, fr, fs, ft;
1487 u32 __user *va;
1488 u32 val;
1489
1490 switch (MIPSInst_FUNC(ir)) {
1491 case lwxc1_op:
1492 va = (void __user *) (xcp->regs[MIPSInst_FR(ir)] +
1493 xcp->regs[MIPSInst_FT(ir)]);
1494
1495 MIPS_FPU_EMU_INC_STATS(loads);
1496 if (!access_ok(VERIFY_READ, va, sizeof(u32))) {
1497 MIPS_FPU_EMU_INC_STATS(errors);
1498 *fault_addr = va;
1499 return SIGBUS;
1500 }
1501 if (__get_user(val, va)) {
1502 MIPS_FPU_EMU_INC_STATS(errors);
1503 *fault_addr = va;
1504 return SIGSEGV;
1505 }
1506 SITOREG(val, MIPSInst_FD(ir));
1507 break;
1508
1509 case swxc1_op:
1510 va = (void __user *) (xcp->regs[MIPSInst_FR(ir)] +
1511 xcp->regs[MIPSInst_FT(ir)]);
1512
1513 MIPS_FPU_EMU_INC_STATS(stores);
1514
1515 SIFROMREG(val, MIPSInst_FS(ir));
1516 if (!access_ok(VERIFY_WRITE, va, sizeof(u32))) {
1517 MIPS_FPU_EMU_INC_STATS(errors);
1518 *fault_addr = va;
1519 return SIGBUS;
1520 }
1521 if (put_user(val, va)) {
1522 MIPS_FPU_EMU_INC_STATS(errors);
1523 *fault_addr = va;
1524 return SIGSEGV;
1525 }
1526 break;
1527
1528 case madd_s_op:
1529 handler = fpemu_sp_madd;
1530 goto scoptop;
1531 case msub_s_op:
1532 handler = fpemu_sp_msub;
1533 goto scoptop;
1534 case nmadd_s_op:
1535 handler = fpemu_sp_nmadd;
1536 goto scoptop;
1537 case nmsub_s_op:
1538 handler = fpemu_sp_nmsub;
1539 goto scoptop;
1540
1541 scoptop:
1542 SPFROMREG(fr, MIPSInst_FR(ir));
1543 SPFROMREG(fs, MIPSInst_FS(ir));
1544 SPFROMREG(ft, MIPSInst_FT(ir));
1545 fd = (*handler) (fr, fs, ft);
1546 SPTOREG(fd, MIPSInst_FD(ir));
1547
1548 copcsr:
1549 if (ieee754_cxtest(IEEE754_INEXACT)) {
1550 MIPS_FPU_EMU_INC_STATS(ieee754_inexact);
1551 rcsr |= FPU_CSR_INE_X | FPU_CSR_INE_S;
1552 }
1553 if (ieee754_cxtest(IEEE754_UNDERFLOW)) {
1554 MIPS_FPU_EMU_INC_STATS(ieee754_underflow);
1555 rcsr |= FPU_CSR_UDF_X | FPU_CSR_UDF_S;
1556 }
1557 if (ieee754_cxtest(IEEE754_OVERFLOW)) {
1558 MIPS_FPU_EMU_INC_STATS(ieee754_overflow);
1559 rcsr |= FPU_CSR_OVF_X | FPU_CSR_OVF_S;
1560 }
1561 if (ieee754_cxtest(IEEE754_INVALID_OPERATION)) {
1562 MIPS_FPU_EMU_INC_STATS(ieee754_invalidop);
1563 rcsr |= FPU_CSR_INV_X | FPU_CSR_INV_S;
1564 }
1565
1566 ctx->fcr31 = (ctx->fcr31 & ~FPU_CSR_ALL_X) | rcsr;
1567 if ((ctx->fcr31 >> 5) & ctx->fcr31 & FPU_CSR_ALL_E) {
1568 /*printk ("SIGFPE: FPU csr = %08x\n",
1569 ctx->fcr31); */
1570 return SIGFPE;
1571 }
1572
1573 break;
1574
1575 default:
1576 return SIGILL;
1577 }
1578 break;
1579 }
1580
1581 case d_fmt:{ /* 1 */
1582 union ieee754dp(*handler) (union ieee754dp, union ieee754dp, union ieee754dp);
1583 union ieee754dp fd, fr, fs, ft;
1584 u64 __user *va;
1585 u64 val;
1586
1587 switch (MIPSInst_FUNC(ir)) {
1588 case ldxc1_op:
1589 va = (void __user *) (xcp->regs[MIPSInst_FR(ir)] +
1590 xcp->regs[MIPSInst_FT(ir)]);
1591
1592 MIPS_FPU_EMU_INC_STATS(loads);
1593 if (!access_ok(VERIFY_READ, va, sizeof(u64))) {
1594 MIPS_FPU_EMU_INC_STATS(errors);
1595 *fault_addr = va;
1596 return SIGBUS;
1597 }
1598 if (__get_user(val, va)) {
1599 MIPS_FPU_EMU_INC_STATS(errors);
1600 *fault_addr = va;
1601 return SIGSEGV;
1602 }
1603 DITOREG(val, MIPSInst_FD(ir));
1604 break;
1605
1606 case sdxc1_op:
1607 va = (void __user *) (xcp->regs[MIPSInst_FR(ir)] +
1608 xcp->regs[MIPSInst_FT(ir)]);
1609
1610 MIPS_FPU_EMU_INC_STATS(stores);
1611 DIFROMREG(val, MIPSInst_FS(ir));
1612 if (!access_ok(VERIFY_WRITE, va, sizeof(u64))) {
1613 MIPS_FPU_EMU_INC_STATS(errors);
1614 *fault_addr = va;
1615 return SIGBUS;
1616 }
1617 if (__put_user(val, va)) {
1618 MIPS_FPU_EMU_INC_STATS(errors);
1619 *fault_addr = va;
1620 return SIGSEGV;
1621 }
1622 break;
1623
1624 case madd_d_op:
1625 handler = fpemu_dp_madd;
1626 goto dcoptop;
1627 case msub_d_op:
1628 handler = fpemu_dp_msub;
1629 goto dcoptop;
1630 case nmadd_d_op:
1631 handler = fpemu_dp_nmadd;
1632 goto dcoptop;
1633 case nmsub_d_op:
1634 handler = fpemu_dp_nmsub;
1635 goto dcoptop;
1636
1637 dcoptop:
1638 DPFROMREG(fr, MIPSInst_FR(ir));
1639 DPFROMREG(fs, MIPSInst_FS(ir));
1640 DPFROMREG(ft, MIPSInst_FT(ir));
1641 fd = (*handler) (fr, fs, ft);
1642 DPTOREG(fd, MIPSInst_FD(ir));
1643 goto copcsr;
1644
1645 default:
1646 return SIGILL;
1647 }
1648 break;
1649 }
1650
1651 case 0x3:
1652 if (MIPSInst_FUNC(ir) != pfetch_op)
1653 return SIGILL;
1654
1655 /* ignore prefx operation */
1656 break;
1657
1658 default:
1659 return SIGILL;
1660 }
1661
1662 return 0;
1663}
1664
1665
1666
1667/*
1668 * Emulate a single COP1 arithmetic instruction.
1669 */
1670static int fpu_emu(struct pt_regs *xcp, struct mips_fpu_struct *ctx,
1671 mips_instruction ir)
1672{
1673 int rfmt; /* resulting format */
1674 unsigned int rcsr = 0; /* resulting csr */
1675 unsigned int oldrm;
1676 unsigned int cbit;
1677 unsigned int cond;
1678 union {
1679 union ieee754dp d;
1680 union ieee754sp s;
1681 int w;
1682 s64 l;
1683 } rv; /* resulting value */
1684 u64 bits;
1685
1686 MIPS_FPU_EMU_INC_STATS(cp1ops);
1687 switch (rfmt = (MIPSInst_FFMT(ir) & 0xf)) {
1688 case s_fmt: { /* 0 */
1689 union {
1690 union ieee754sp(*b) (union ieee754sp, union ieee754sp);
1691 union ieee754sp(*u) (union ieee754sp);
1692 } handler;
1693 union ieee754sp fd, fs, ft;
1694
1695 switch (MIPSInst_FUNC(ir)) {
1696 /* binary ops */
1697 case fadd_op:
1698 MIPS_FPU_EMU_INC_STATS(add_s);
1699 handler.b = ieee754sp_add;
1700 goto scopbop;
1701 case fsub_op:
1702 MIPS_FPU_EMU_INC_STATS(sub_s);
1703 handler.b = ieee754sp_sub;
1704 goto scopbop;
1705 case fmul_op:
1706 MIPS_FPU_EMU_INC_STATS(mul_s);
1707 handler.b = ieee754sp_mul;
1708 goto scopbop;
1709 case fdiv_op:
1710 MIPS_FPU_EMU_INC_STATS(div_s);
1711 handler.b = ieee754sp_div;
1712 goto scopbop;
1713
1714 /* unary ops */
1715 case fsqrt_op:
1716 if (!cpu_has_mips_2_3_4_5_r)
1717 return SIGILL;
1718
1719 MIPS_FPU_EMU_INC_STATS(sqrt_s);
1720 handler.u = ieee754sp_sqrt;
1721 goto scopuop;
1722
1723 /*
1724 * Note that on some MIPS IV implementations such as the
1725 * R5000 and R8000 the FSQRT and FRECIP instructions do not
1726 * achieve full IEEE-754 accuracy - however this emulator does.
1727 */
1728 case frsqrt_op:
1729 if (!cpu_has_mips_4_5_64_r2_r6)
1730 return SIGILL;
1731
1732 MIPS_FPU_EMU_INC_STATS(rsqrt_s);
1733 handler.u = fpemu_sp_rsqrt;
1734 goto scopuop;
1735
1736 case frecip_op:
1737 if (!cpu_has_mips_4_5_64_r2_r6)
1738 return SIGILL;
1739
1740 MIPS_FPU_EMU_INC_STATS(recip_s);
1741 handler.u = fpemu_sp_recip;
1742 goto scopuop;
1743
1744 case fmovc_op:
1745 if (!cpu_has_mips_4_5_r)
1746 return SIGILL;
1747
1748 cond = fpucondbit[MIPSInst_FT(ir) >> 2];
1749 if (((ctx->fcr31 & cond) != 0) !=
1750 ((MIPSInst_FT(ir) & 1) != 0))
1751 return 0;
1752 SPFROMREG(rv.s, MIPSInst_FS(ir));
1753 break;
1754
1755 case fmovz_op:
1756 if (!cpu_has_mips_4_5_r)
1757 return SIGILL;
1758
1759 if (xcp->regs[MIPSInst_FT(ir)] != 0)
1760 return 0;
1761 SPFROMREG(rv.s, MIPSInst_FS(ir));
1762 break;
1763
1764 case fmovn_op:
1765 if (!cpu_has_mips_4_5_r)
1766 return SIGILL;
1767
1768 if (xcp->regs[MIPSInst_FT(ir)] == 0)
1769 return 0;
1770 SPFROMREG(rv.s, MIPSInst_FS(ir));
1771 break;
1772
1773 case fseleqz_op:
1774 if (!cpu_has_mips_r6)
1775 return SIGILL;
1776
1777 MIPS_FPU_EMU_INC_STATS(seleqz_s);
1778 SPFROMREG(rv.s, MIPSInst_FT(ir));
1779 if (rv.w & 0x1)
1780 rv.w = 0;
1781 else
1782 SPFROMREG(rv.s, MIPSInst_FS(ir));
1783 break;
1784
1785 case fselnez_op:
1786 if (!cpu_has_mips_r6)
1787 return SIGILL;
1788
1789 MIPS_FPU_EMU_INC_STATS(selnez_s);
1790 SPFROMREG(rv.s, MIPSInst_FT(ir));
1791 if (rv.w & 0x1)
1792 SPFROMREG(rv.s, MIPSInst_FS(ir));
1793 else
1794 rv.w = 0;
1795 break;
1796
1797 case fmaddf_op: {
1798 union ieee754sp ft, fs, fd;
1799
1800 if (!cpu_has_mips_r6)
1801 return SIGILL;
1802
1803 MIPS_FPU_EMU_INC_STATS(maddf_s);
1804 SPFROMREG(ft, MIPSInst_FT(ir));
1805 SPFROMREG(fs, MIPSInst_FS(ir));
1806 SPFROMREG(fd, MIPSInst_FD(ir));
1807 rv.s = ieee754sp_maddf(fd, fs, ft);
1808 goto copcsr;
1809 }
1810
1811 case fmsubf_op: {
1812 union ieee754sp ft, fs, fd;
1813
1814 if (!cpu_has_mips_r6)
1815 return SIGILL;
1816
1817 MIPS_FPU_EMU_INC_STATS(msubf_s);
1818 SPFROMREG(ft, MIPSInst_FT(ir));
1819 SPFROMREG(fs, MIPSInst_FS(ir));
1820 SPFROMREG(fd, MIPSInst_FD(ir));
1821 rv.s = ieee754sp_msubf(fd, fs, ft);
1822 goto copcsr;
1823 }
1824
1825 case frint_op: {
1826 union ieee754sp fs;
1827
1828 if (!cpu_has_mips_r6)
1829 return SIGILL;
1830
1831 MIPS_FPU_EMU_INC_STATS(rint_s);
1832 SPFROMREG(fs, MIPSInst_FS(ir));
1833 rv.s = ieee754sp_rint(fs);
1834 goto copcsr;
1835 }
1836
1837 case fclass_op: {
1838 union ieee754sp fs;
1839
1840 if (!cpu_has_mips_r6)
1841 return SIGILL;
1842
1843 MIPS_FPU_EMU_INC_STATS(class_s);
1844 SPFROMREG(fs, MIPSInst_FS(ir));
1845 rv.w = ieee754sp_2008class(fs);
1846 rfmt = w_fmt;
1847 goto copcsr;
1848 }
1849
1850 case fmin_op: {
1851 union ieee754sp fs, ft;
1852
1853 if (!cpu_has_mips_r6)
1854 return SIGILL;
1855
1856 MIPS_FPU_EMU_INC_STATS(min_s);
1857 SPFROMREG(ft, MIPSInst_FT(ir));
1858 SPFROMREG(fs, MIPSInst_FS(ir));
1859 rv.s = ieee754sp_fmin(fs, ft);
1860 goto copcsr;
1861 }
1862
1863 case fmina_op: {
1864 union ieee754sp fs, ft;
1865
1866 if (!cpu_has_mips_r6)
1867 return SIGILL;
1868
1869 MIPS_FPU_EMU_INC_STATS(mina_s);
1870 SPFROMREG(ft, MIPSInst_FT(ir));
1871 SPFROMREG(fs, MIPSInst_FS(ir));
1872 rv.s = ieee754sp_fmina(fs, ft);
1873 goto copcsr;
1874 }
1875
1876 case fmax_op: {
1877 union ieee754sp fs, ft;
1878
1879 if (!cpu_has_mips_r6)
1880 return SIGILL;
1881
1882 MIPS_FPU_EMU_INC_STATS(max_s);
1883 SPFROMREG(ft, MIPSInst_FT(ir));
1884 SPFROMREG(fs, MIPSInst_FS(ir));
1885 rv.s = ieee754sp_fmax(fs, ft);
1886 goto copcsr;
1887 }
1888
1889 case fmaxa_op: {
1890 union ieee754sp fs, ft;
1891
1892 if (!cpu_has_mips_r6)
1893 return SIGILL;
1894
1895 MIPS_FPU_EMU_INC_STATS(maxa_s);
1896 SPFROMREG(ft, MIPSInst_FT(ir));
1897 SPFROMREG(fs, MIPSInst_FS(ir));
1898 rv.s = ieee754sp_fmaxa(fs, ft);
1899 goto copcsr;
1900 }
1901
1902 case fabs_op:
1903 MIPS_FPU_EMU_INC_STATS(abs_s);
1904 handler.u = ieee754sp_abs;
1905 goto scopuop;
1906
1907 case fneg_op:
1908 MIPS_FPU_EMU_INC_STATS(neg_s);
1909 handler.u = ieee754sp_neg;
1910 goto scopuop;
1911
1912 case fmov_op:
1913 /* an easy one */
1914 MIPS_FPU_EMU_INC_STATS(mov_s);
1915 SPFROMREG(rv.s, MIPSInst_FS(ir));
1916 goto copcsr;
1917
1918 /* binary op on handler */
1919scopbop:
1920 SPFROMREG(fs, MIPSInst_FS(ir));
1921 SPFROMREG(ft, MIPSInst_FT(ir));
1922
1923 rv.s = (*handler.b) (fs, ft);
1924 goto copcsr;
1925scopuop:
1926 SPFROMREG(fs, MIPSInst_FS(ir));
1927 rv.s = (*handler.u) (fs);
1928 goto copcsr;
1929copcsr:
1930 if (ieee754_cxtest(IEEE754_INEXACT)) {
1931 MIPS_FPU_EMU_INC_STATS(ieee754_inexact);
1932 rcsr |= FPU_CSR_INE_X | FPU_CSR_INE_S;
1933 }
1934 if (ieee754_cxtest(IEEE754_UNDERFLOW)) {
1935 MIPS_FPU_EMU_INC_STATS(ieee754_underflow);
1936 rcsr |= FPU_CSR_UDF_X | FPU_CSR_UDF_S;
1937 }
1938 if (ieee754_cxtest(IEEE754_OVERFLOW)) {
1939 MIPS_FPU_EMU_INC_STATS(ieee754_overflow);
1940 rcsr |= FPU_CSR_OVF_X | FPU_CSR_OVF_S;
1941 }
1942 if (ieee754_cxtest(IEEE754_ZERO_DIVIDE)) {
1943 MIPS_FPU_EMU_INC_STATS(ieee754_zerodiv);
1944 rcsr |= FPU_CSR_DIV_X | FPU_CSR_DIV_S;
1945 }
1946 if (ieee754_cxtest(IEEE754_INVALID_OPERATION)) {
1947 MIPS_FPU_EMU_INC_STATS(ieee754_invalidop);
1948 rcsr |= FPU_CSR_INV_X | FPU_CSR_INV_S;
1949 }
1950 break;
1951
1952 /* unary conv ops */
1953 case fcvts_op:
1954 return SIGILL; /* not defined */
1955
1956 case fcvtd_op:
1957 MIPS_FPU_EMU_INC_STATS(cvt_d_s);
1958 SPFROMREG(fs, MIPSInst_FS(ir));
1959 rv.d = ieee754dp_fsp(fs);
1960 rfmt = d_fmt;
1961 goto copcsr;
1962
1963 case fcvtw_op:
1964 MIPS_FPU_EMU_INC_STATS(cvt_w_s);
1965 SPFROMREG(fs, MIPSInst_FS(ir));
1966 rv.w = ieee754sp_tint(fs);
1967 rfmt = w_fmt;
1968 goto copcsr;
1969
1970 case fround_op:
1971 case ftrunc_op:
1972 case fceil_op:
1973 case ffloor_op:
1974 if (!cpu_has_mips_2_3_4_5_r)
1975 return SIGILL;
1976
1977 if (MIPSInst_FUNC(ir) == fceil_op)
1978 MIPS_FPU_EMU_INC_STATS(ceil_w_s);
1979 if (MIPSInst_FUNC(ir) == ffloor_op)
1980 MIPS_FPU_EMU_INC_STATS(floor_w_s);
1981 if (MIPSInst_FUNC(ir) == fround_op)
1982 MIPS_FPU_EMU_INC_STATS(round_w_s);
1983 if (MIPSInst_FUNC(ir) == ftrunc_op)
1984 MIPS_FPU_EMU_INC_STATS(trunc_w_s);
1985
1986 oldrm = ieee754_csr.rm;
1987 SPFROMREG(fs, MIPSInst_FS(ir));
1988 ieee754_csr.rm = MIPSInst_FUNC(ir);
1989 rv.w = ieee754sp_tint(fs);
1990 ieee754_csr.rm = oldrm;
1991 rfmt = w_fmt;
1992 goto copcsr;
1993
1994 case fsel_op:
1995 if (!cpu_has_mips_r6)
1996 return SIGILL;
1997
1998 MIPS_FPU_EMU_INC_STATS(sel_s);
1999 SPFROMREG(fd, MIPSInst_FD(ir));
2000 if (fd.bits & 0x1)
2001 SPFROMREG(rv.s, MIPSInst_FT(ir));
2002 else
2003 SPFROMREG(rv.s, MIPSInst_FS(ir));
2004 break;
2005
2006 case fcvtl_op:
2007 if (!cpu_has_mips_3_4_5_64_r2_r6)
2008 return SIGILL;
2009
2010 MIPS_FPU_EMU_INC_STATS(cvt_l_s);
2011 SPFROMREG(fs, MIPSInst_FS(ir));
2012 rv.l = ieee754sp_tlong(fs);
2013 rfmt = l_fmt;
2014 goto copcsr;
2015
2016 case froundl_op:
2017 case ftruncl_op:
2018 case fceill_op:
2019 case ffloorl_op:
2020 if (!cpu_has_mips_3_4_5_64_r2_r6)
2021 return SIGILL;
2022
2023 if (MIPSInst_FUNC(ir) == fceill_op)
2024 MIPS_FPU_EMU_INC_STATS(ceil_l_s);
2025 if (MIPSInst_FUNC(ir) == ffloorl_op)
2026 MIPS_FPU_EMU_INC_STATS(floor_l_s);
2027 if (MIPSInst_FUNC(ir) == froundl_op)
2028 MIPS_FPU_EMU_INC_STATS(round_l_s);
2029 if (MIPSInst_FUNC(ir) == ftruncl_op)
2030 MIPS_FPU_EMU_INC_STATS(trunc_l_s);
2031
2032 oldrm = ieee754_csr.rm;
2033 SPFROMREG(fs, MIPSInst_FS(ir));
2034 ieee754_csr.rm = MIPSInst_FUNC(ir);
2035 rv.l = ieee754sp_tlong(fs);
2036 ieee754_csr.rm = oldrm;
2037 rfmt = l_fmt;
2038 goto copcsr;
2039
2040 default:
2041 if (!NO_R6EMU && MIPSInst_FUNC(ir) >= fcmp_op) {
2042 unsigned int cmpop;
2043 union ieee754sp fs, ft;
2044
2045 cmpop = MIPSInst_FUNC(ir) - fcmp_op;
2046 SPFROMREG(fs, MIPSInst_FS(ir));
2047 SPFROMREG(ft, MIPSInst_FT(ir));
2048 rv.w = ieee754sp_cmp(fs, ft,
2049 cmptab[cmpop & 0x7], cmpop & 0x8);
2050 rfmt = -1;
2051 if ((cmpop & 0x8) && ieee754_cxtest
2052 (IEEE754_INVALID_OPERATION))
2053 rcsr = FPU_CSR_INV_X | FPU_CSR_INV_S;
2054 else
2055 goto copcsr;
2056
2057 } else
2058 return SIGILL;
2059 break;
2060 }
2061 break;
2062 }
2063
2064 case d_fmt: {
2065 union ieee754dp fd, fs, ft;
2066 union {
2067 union ieee754dp(*b) (union ieee754dp, union ieee754dp);
2068 union ieee754dp(*u) (union ieee754dp);
2069 } handler;
2070
2071 switch (MIPSInst_FUNC(ir)) {
2072 /* binary ops */
2073 case fadd_op:
2074 MIPS_FPU_EMU_INC_STATS(add_d);
2075 handler.b = ieee754dp_add;
2076 goto dcopbop;
2077 case fsub_op:
2078 MIPS_FPU_EMU_INC_STATS(sub_d);
2079 handler.b = ieee754dp_sub;
2080 goto dcopbop;
2081 case fmul_op:
2082 MIPS_FPU_EMU_INC_STATS(mul_d);
2083 handler.b = ieee754dp_mul;
2084 goto dcopbop;
2085 case fdiv_op:
2086 MIPS_FPU_EMU_INC_STATS(div_d);
2087 handler.b = ieee754dp_div;
2088 goto dcopbop;
2089
2090 /* unary ops */
2091 case fsqrt_op:
2092 if (!cpu_has_mips_2_3_4_5_r)
2093 return SIGILL;
2094
2095 MIPS_FPU_EMU_INC_STATS(sqrt_d);
2096 handler.u = ieee754dp_sqrt;
2097 goto dcopuop;
2098 /*
2099 * Note that on some MIPS IV implementations such as the
2100 * R5000 and R8000 the FSQRT and FRECIP instructions do not
2101 * achieve full IEEE-754 accuracy - however this emulator does.
2102 */
2103 case frsqrt_op:
2104 if (!cpu_has_mips_4_5_64_r2_r6)
2105 return SIGILL;
2106
2107 MIPS_FPU_EMU_INC_STATS(rsqrt_d);
2108 handler.u = fpemu_dp_rsqrt;
2109 goto dcopuop;
2110 case frecip_op:
2111 if (!cpu_has_mips_4_5_64_r2_r6)
2112 return SIGILL;
2113
2114 MIPS_FPU_EMU_INC_STATS(recip_d);
2115 handler.u = fpemu_dp_recip;
2116 goto dcopuop;
2117 case fmovc_op:
2118 if (!cpu_has_mips_4_5_r)
2119 return SIGILL;
2120
2121 cond = fpucondbit[MIPSInst_FT(ir) >> 2];
2122 if (((ctx->fcr31 & cond) != 0) !=
2123 ((MIPSInst_FT(ir) & 1) != 0))
2124 return 0;
2125 DPFROMREG(rv.d, MIPSInst_FS(ir));
2126 break;
2127 case fmovz_op:
2128 if (!cpu_has_mips_4_5_r)
2129 return SIGILL;
2130
2131 if (xcp->regs[MIPSInst_FT(ir)] != 0)
2132 return 0;
2133 DPFROMREG(rv.d, MIPSInst_FS(ir));
2134 break;
2135 case fmovn_op:
2136 if (!cpu_has_mips_4_5_r)
2137 return SIGILL;
2138
2139 if (xcp->regs[MIPSInst_FT(ir)] == 0)
2140 return 0;
2141 DPFROMREG(rv.d, MIPSInst_FS(ir));
2142 break;
2143
2144 case fseleqz_op:
2145 if (!cpu_has_mips_r6)
2146 return SIGILL;
2147
2148 MIPS_FPU_EMU_INC_STATS(seleqz_d);
2149 DPFROMREG(rv.d, MIPSInst_FT(ir));
2150 if (rv.l & 0x1)
2151 rv.l = 0;
2152 else
2153 DPFROMREG(rv.d, MIPSInst_FS(ir));
2154 break;
2155
2156 case fselnez_op:
2157 if (!cpu_has_mips_r6)
2158 return SIGILL;
2159
2160 MIPS_FPU_EMU_INC_STATS(selnez_d);
2161 DPFROMREG(rv.d, MIPSInst_FT(ir));
2162 if (rv.l & 0x1)
2163 DPFROMREG(rv.d, MIPSInst_FS(ir));
2164 else
2165 rv.l = 0;
2166 break;
2167
2168 case fmaddf_op: {
2169 union ieee754dp ft, fs, fd;
2170
2171 if (!cpu_has_mips_r6)
2172 return SIGILL;
2173
2174 MIPS_FPU_EMU_INC_STATS(maddf_d);
2175 DPFROMREG(ft, MIPSInst_FT(ir));
2176 DPFROMREG(fs, MIPSInst_FS(ir));
2177 DPFROMREG(fd, MIPSInst_FD(ir));
2178 rv.d = ieee754dp_maddf(fd, fs, ft);
2179 goto copcsr;
2180 }
2181
2182 case fmsubf_op: {
2183 union ieee754dp ft, fs, fd;
2184
2185 if (!cpu_has_mips_r6)
2186 return SIGILL;
2187
2188 MIPS_FPU_EMU_INC_STATS(msubf_d);
2189 DPFROMREG(ft, MIPSInst_FT(ir));
2190 DPFROMREG(fs, MIPSInst_FS(ir));
2191 DPFROMREG(fd, MIPSInst_FD(ir));
2192 rv.d = ieee754dp_msubf(fd, fs, ft);
2193 goto copcsr;
2194 }
2195
2196 case frint_op: {
2197 union ieee754dp fs;
2198
2199 if (!cpu_has_mips_r6)
2200 return SIGILL;
2201
2202 MIPS_FPU_EMU_INC_STATS(rint_d);
2203 DPFROMREG(fs, MIPSInst_FS(ir));
2204 rv.d = ieee754dp_rint(fs);
2205 goto copcsr;
2206 }
2207
2208 case fclass_op: {
2209 union ieee754dp fs;
2210
2211 if (!cpu_has_mips_r6)
2212 return SIGILL;
2213
2214 MIPS_FPU_EMU_INC_STATS(class_d);
2215 DPFROMREG(fs, MIPSInst_FS(ir));
2216 rv.l = ieee754dp_2008class(fs);
2217 rfmt = l_fmt;
2218 goto copcsr;
2219 }
2220
2221 case fmin_op: {
2222 union ieee754dp fs, ft;
2223
2224 if (!cpu_has_mips_r6)
2225 return SIGILL;
2226
2227 MIPS_FPU_EMU_INC_STATS(min_d);
2228 DPFROMREG(ft, MIPSInst_FT(ir));
2229 DPFROMREG(fs, MIPSInst_FS(ir));
2230 rv.d = ieee754dp_fmin(fs, ft);
2231 goto copcsr;
2232 }
2233
2234 case fmina_op: {
2235 union ieee754dp fs, ft;
2236
2237 if (!cpu_has_mips_r6)
2238 return SIGILL;
2239
2240 MIPS_FPU_EMU_INC_STATS(mina_d);
2241 DPFROMREG(ft, MIPSInst_FT(ir));
2242 DPFROMREG(fs, MIPSInst_FS(ir));
2243 rv.d = ieee754dp_fmina(fs, ft);
2244 goto copcsr;
2245 }
2246
2247 case fmax_op: {
2248 union ieee754dp fs, ft;
2249
2250 if (!cpu_has_mips_r6)
2251 return SIGILL;
2252
2253 MIPS_FPU_EMU_INC_STATS(max_d);
2254 DPFROMREG(ft, MIPSInst_FT(ir));
2255 DPFROMREG(fs, MIPSInst_FS(ir));
2256 rv.d = ieee754dp_fmax(fs, ft);
2257 goto copcsr;
2258 }
2259
2260 case fmaxa_op: {
2261 union ieee754dp fs, ft;
2262
2263 if (!cpu_has_mips_r6)
2264 return SIGILL;
2265
2266 MIPS_FPU_EMU_INC_STATS(maxa_d);
2267 DPFROMREG(ft, MIPSInst_FT(ir));
2268 DPFROMREG(fs, MIPSInst_FS(ir));
2269 rv.d = ieee754dp_fmaxa(fs, ft);
2270 goto copcsr;
2271 }
2272
2273 case fabs_op:
2274 MIPS_FPU_EMU_INC_STATS(abs_d);
2275 handler.u = ieee754dp_abs;
2276 goto dcopuop;
2277
2278 case fneg_op:
2279 MIPS_FPU_EMU_INC_STATS(neg_d);
2280 handler.u = ieee754dp_neg;
2281 goto dcopuop;
2282
2283 case fmov_op:
2284 /* an easy one */
2285 MIPS_FPU_EMU_INC_STATS(mov_d);
2286 DPFROMREG(rv.d, MIPSInst_FS(ir));
2287 goto copcsr;
2288
2289 /* binary op on handler */
2290dcopbop:
2291 DPFROMREG(fs, MIPSInst_FS(ir));
2292 DPFROMREG(ft, MIPSInst_FT(ir));
2293
2294 rv.d = (*handler.b) (fs, ft);
2295 goto copcsr;
2296dcopuop:
2297 DPFROMREG(fs, MIPSInst_FS(ir));
2298 rv.d = (*handler.u) (fs);
2299 goto copcsr;
2300
2301 /*
2302 * unary conv ops
2303 */
2304 case fcvts_op:
2305 MIPS_FPU_EMU_INC_STATS(cvt_s_d);
2306 DPFROMREG(fs, MIPSInst_FS(ir));
2307 rv.s = ieee754sp_fdp(fs);
2308 rfmt = s_fmt;
2309 goto copcsr;
2310
2311 case fcvtd_op:
2312 return SIGILL; /* not defined */
2313
2314 case fcvtw_op:
2315 MIPS_FPU_EMU_INC_STATS(cvt_w_d);
2316 DPFROMREG(fs, MIPSInst_FS(ir));
2317 rv.w = ieee754dp_tint(fs); /* wrong */
2318 rfmt = w_fmt;
2319 goto copcsr;
2320
2321 case fround_op:
2322 case ftrunc_op:
2323 case fceil_op:
2324 case ffloor_op:
2325 if (!cpu_has_mips_2_3_4_5_r)
2326 return SIGILL;
2327
2328 if (MIPSInst_FUNC(ir) == fceil_op)
2329 MIPS_FPU_EMU_INC_STATS(ceil_w_d);
2330 if (MIPSInst_FUNC(ir) == ffloor_op)
2331 MIPS_FPU_EMU_INC_STATS(floor_w_d);
2332 if (MIPSInst_FUNC(ir) == fround_op)
2333 MIPS_FPU_EMU_INC_STATS(round_w_d);
2334 if (MIPSInst_FUNC(ir) == ftrunc_op)
2335 MIPS_FPU_EMU_INC_STATS(trunc_w_d);
2336
2337 oldrm = ieee754_csr.rm;
2338 DPFROMREG(fs, MIPSInst_FS(ir));
2339 ieee754_csr.rm = MIPSInst_FUNC(ir);
2340 rv.w = ieee754dp_tint(fs);
2341 ieee754_csr.rm = oldrm;
2342 rfmt = w_fmt;
2343 goto copcsr;
2344
2345 case fsel_op:
2346 if (!cpu_has_mips_r6)
2347 return SIGILL;
2348
2349 MIPS_FPU_EMU_INC_STATS(sel_d);
2350 DPFROMREG(fd, MIPSInst_FD(ir));
2351 if (fd.bits & 0x1)
2352 DPFROMREG(rv.d, MIPSInst_FT(ir));
2353 else
2354 DPFROMREG(rv.d, MIPSInst_FS(ir));
2355 break;
2356
2357 case fcvtl_op:
2358 if (!cpu_has_mips_3_4_5_64_r2_r6)
2359 return SIGILL;
2360
2361 MIPS_FPU_EMU_INC_STATS(cvt_l_d);
2362 DPFROMREG(fs, MIPSInst_FS(ir));
2363 rv.l = ieee754dp_tlong(fs);
2364 rfmt = l_fmt;
2365 goto copcsr;
2366
2367 case froundl_op:
2368 case ftruncl_op:
2369 case fceill_op:
2370 case ffloorl_op:
2371 if (!cpu_has_mips_3_4_5_64_r2_r6)
2372 return SIGILL;
2373
2374 if (MIPSInst_FUNC(ir) == fceill_op)
2375 MIPS_FPU_EMU_INC_STATS(ceil_l_d);
2376 if (MIPSInst_FUNC(ir) == ffloorl_op)
2377 MIPS_FPU_EMU_INC_STATS(floor_l_d);
2378 if (MIPSInst_FUNC(ir) == froundl_op)
2379 MIPS_FPU_EMU_INC_STATS(round_l_d);
2380 if (MIPSInst_FUNC(ir) == ftruncl_op)
2381 MIPS_FPU_EMU_INC_STATS(trunc_l_d);
2382
2383 oldrm = ieee754_csr.rm;
2384 DPFROMREG(fs, MIPSInst_FS(ir));
2385 ieee754_csr.rm = MIPSInst_FUNC(ir);
2386 rv.l = ieee754dp_tlong(fs);
2387 ieee754_csr.rm = oldrm;
2388 rfmt = l_fmt;
2389 goto copcsr;
2390
2391 default:
2392 if (!NO_R6EMU && MIPSInst_FUNC(ir) >= fcmp_op) {
2393 unsigned int cmpop;
2394 union ieee754dp fs, ft;
2395
2396 cmpop = MIPSInst_FUNC(ir) - fcmp_op;
2397 DPFROMREG(fs, MIPSInst_FS(ir));
2398 DPFROMREG(ft, MIPSInst_FT(ir));
2399 rv.w = ieee754dp_cmp(fs, ft,
2400 cmptab[cmpop & 0x7], cmpop & 0x8);
2401 rfmt = -1;
2402 if ((cmpop & 0x8)
2403 &&
2404 ieee754_cxtest
2405 (IEEE754_INVALID_OPERATION))
2406 rcsr = FPU_CSR_INV_X | FPU_CSR_INV_S;
2407 else
2408 goto copcsr;
2409
2410 }
2411 else {
2412 return SIGILL;
2413 }
2414 break;
2415 }
2416 break;
2417 }
2418
2419 case w_fmt: {
2420 union ieee754dp fs;
2421
2422 switch (MIPSInst_FUNC(ir)) {
2423 case fcvts_op:
2424 /* convert word to single precision real */
2425 MIPS_FPU_EMU_INC_STATS(cvt_s_w);
2426 SPFROMREG(fs, MIPSInst_FS(ir));
2427 rv.s = ieee754sp_fint(fs.bits);
2428 rfmt = s_fmt;
2429 goto copcsr;
2430 case fcvtd_op:
2431 /* convert word to double precision real */
2432 MIPS_FPU_EMU_INC_STATS(cvt_d_w);
2433 SPFROMREG(fs, MIPSInst_FS(ir));
2434 rv.d = ieee754dp_fint(fs.bits);
2435 rfmt = d_fmt;
2436 goto copcsr;
2437 default: {
2438 /* Emulating the new CMP.condn.fmt R6 instruction */
2439#define CMPOP_MASK 0x7
2440#define SIGN_BIT (0x1 << 3)
2441#define PREDICATE_BIT (0x1 << 4)
2442
2443 int cmpop = MIPSInst_FUNC(ir) & CMPOP_MASK;
2444 int sig = MIPSInst_FUNC(ir) & SIGN_BIT;
2445 union ieee754sp fs, ft;
2446
2447 /* This is an R6 only instruction */
2448 if (!cpu_has_mips_r6 ||
2449 (MIPSInst_FUNC(ir) & 0x20))
2450 return SIGILL;
2451
2452 if (!sig) {
2453 if (!(MIPSInst_FUNC(ir) & PREDICATE_BIT)) {
2454 switch (cmpop) {
2455 case 0:
2456 MIPS_FPU_EMU_INC_STATS(cmp_af_s);
2457 break;
2458 case 1:
2459 MIPS_FPU_EMU_INC_STATS(cmp_un_s);
2460 break;
2461 case 2:
2462 MIPS_FPU_EMU_INC_STATS(cmp_eq_s);
2463 break;
2464 case 3:
2465 MIPS_FPU_EMU_INC_STATS(cmp_ueq_s);
2466 break;
2467 case 4:
2468 MIPS_FPU_EMU_INC_STATS(cmp_lt_s);
2469 break;
2470 case 5:
2471 MIPS_FPU_EMU_INC_STATS(cmp_ult_s);
2472 break;
2473 case 6:
2474 MIPS_FPU_EMU_INC_STATS(cmp_le_s);
2475 break;
2476 case 7:
2477 MIPS_FPU_EMU_INC_STATS(cmp_ule_s);
2478 break;
2479 }
2480 } else {
2481 switch (cmpop) {
2482 case 1:
2483 MIPS_FPU_EMU_INC_STATS(cmp_or_s);
2484 break;
2485 case 2:
2486 MIPS_FPU_EMU_INC_STATS(cmp_une_s);
2487 break;
2488 case 3:
2489 MIPS_FPU_EMU_INC_STATS(cmp_ne_s);
2490 break;
2491 }
2492 }
2493 } else {
2494 if (!(MIPSInst_FUNC(ir) & PREDICATE_BIT)) {
2495 switch (cmpop) {
2496 case 0:
2497 MIPS_FPU_EMU_INC_STATS(cmp_saf_s);
2498 break;
2499 case 1:
2500 MIPS_FPU_EMU_INC_STATS(cmp_sun_s);
2501 break;
2502 case 2:
2503 MIPS_FPU_EMU_INC_STATS(cmp_seq_s);
2504 break;
2505 case 3:
2506 MIPS_FPU_EMU_INC_STATS(cmp_sueq_s);
2507 break;
2508 case 4:
2509 MIPS_FPU_EMU_INC_STATS(cmp_slt_s);
2510 break;
2511 case 5:
2512 MIPS_FPU_EMU_INC_STATS(cmp_sult_s);
2513 break;
2514 case 6:
2515 MIPS_FPU_EMU_INC_STATS(cmp_sle_s);
2516 break;
2517 case 7:
2518 MIPS_FPU_EMU_INC_STATS(cmp_sule_s);
2519 break;
2520 }
2521 } else {
2522 switch (cmpop) {
2523 case 1:
2524 MIPS_FPU_EMU_INC_STATS(cmp_sor_s);
2525 break;
2526 case 2:
2527 MIPS_FPU_EMU_INC_STATS(cmp_sune_s);
2528 break;
2529 case 3:
2530 MIPS_FPU_EMU_INC_STATS(cmp_sne_s);
2531 break;
2532 }
2533 }
2534 }
2535
2536 /* fmt is w_fmt for single precision so fix it */
2537 rfmt = s_fmt;
2538 /* default to false */
2539 rv.w = 0;
2540
2541 /* CMP.condn.S */
2542 SPFROMREG(fs, MIPSInst_FS(ir));
2543 SPFROMREG(ft, MIPSInst_FT(ir));
2544
2545 /* positive predicates */
2546 if (!(MIPSInst_FUNC(ir) & PREDICATE_BIT)) {
2547 if (ieee754sp_cmp(fs, ft, cmptab[cmpop],
2548 sig))
2549 rv.w = -1; /* true, all 1s */
2550 if ((sig) &&
2551 ieee754_cxtest(IEEE754_INVALID_OPERATION))
2552 rcsr = FPU_CSR_INV_X | FPU_CSR_INV_S;
2553 else
2554 goto copcsr;
2555 } else {
2556 /* negative predicates */
2557 switch (cmpop) {
2558 case 1:
2559 case 2:
2560 case 3:
2561 if (ieee754sp_cmp(fs, ft,
2562 negative_cmptab[cmpop],
2563 sig))
2564 rv.w = -1; /* true, all 1s */
2565 if (sig &&
2566 ieee754_cxtest(IEEE754_INVALID_OPERATION))
2567 rcsr = FPU_CSR_INV_X | FPU_CSR_INV_S;
2568 else
2569 goto copcsr;
2570 break;
2571 default:
2572 /* Reserved R6 ops */
2573 return SIGILL;
2574 }
2575 }
2576 break;
2577 }
2578 }
2579 break;
2580 }
2581
2582 case l_fmt:
2583
2584 if (!cpu_has_mips_3_4_5_64_r2_r6)
2585 return SIGILL;
2586
2587 DIFROMREG(bits, MIPSInst_FS(ir));
2588
2589 switch (MIPSInst_FUNC(ir)) {
2590 case fcvts_op:
2591 /* convert long to single precision real */
2592 MIPS_FPU_EMU_INC_STATS(cvt_s_l);
2593 rv.s = ieee754sp_flong(bits);
2594 rfmt = s_fmt;
2595 goto copcsr;
2596 case fcvtd_op:
2597 /* convert long to double precision real */
2598 MIPS_FPU_EMU_INC_STATS(cvt_d_l);
2599 rv.d = ieee754dp_flong(bits);
2600 rfmt = d_fmt;
2601 goto copcsr;
2602 default: {
2603 /* Emulating the new CMP.condn.fmt R6 instruction */
2604 int cmpop = MIPSInst_FUNC(ir) & CMPOP_MASK;
2605 int sig = MIPSInst_FUNC(ir) & SIGN_BIT;
2606 union ieee754dp fs, ft;
2607
2608 if (!cpu_has_mips_r6 ||
2609 (MIPSInst_FUNC(ir) & 0x20))
2610 return SIGILL;
2611
2612 if (!sig) {
2613 if (!(MIPSInst_FUNC(ir) & PREDICATE_BIT)) {
2614 switch (cmpop) {
2615 case 0:
2616 MIPS_FPU_EMU_INC_STATS(cmp_af_d);
2617 break;
2618 case 1:
2619 MIPS_FPU_EMU_INC_STATS(cmp_un_d);
2620 break;
2621 case 2:
2622 MIPS_FPU_EMU_INC_STATS(cmp_eq_d);
2623 break;
2624 case 3:
2625 MIPS_FPU_EMU_INC_STATS(cmp_ueq_d);
2626 break;
2627 case 4:
2628 MIPS_FPU_EMU_INC_STATS(cmp_lt_d);
2629 break;
2630 case 5:
2631 MIPS_FPU_EMU_INC_STATS(cmp_ult_d);
2632 break;
2633 case 6:
2634 MIPS_FPU_EMU_INC_STATS(cmp_le_d);
2635 break;
2636 case 7:
2637 MIPS_FPU_EMU_INC_STATS(cmp_ule_d);
2638 break;
2639 }
2640 } else {
2641 switch (cmpop) {
2642 case 1:
2643 MIPS_FPU_EMU_INC_STATS(cmp_or_d);
2644 break;
2645 case 2:
2646 MIPS_FPU_EMU_INC_STATS(cmp_une_d);
2647 break;
2648 case 3:
2649 MIPS_FPU_EMU_INC_STATS(cmp_ne_d);
2650 break;
2651 }
2652 }
2653 } else {
2654 if (!(MIPSInst_FUNC(ir) & PREDICATE_BIT)) {
2655 switch (cmpop) {
2656 case 0:
2657 MIPS_FPU_EMU_INC_STATS(cmp_saf_d);
2658 break;
2659 case 1:
2660 MIPS_FPU_EMU_INC_STATS(cmp_sun_d);
2661 break;
2662 case 2:
2663 MIPS_FPU_EMU_INC_STATS(cmp_seq_d);
2664 break;
2665 case 3:
2666 MIPS_FPU_EMU_INC_STATS(cmp_sueq_d);
2667 break;
2668 case 4:
2669 MIPS_FPU_EMU_INC_STATS(cmp_slt_d);
2670 break;
2671 case 5:
2672 MIPS_FPU_EMU_INC_STATS(cmp_sult_d);
2673 break;
2674 case 6:
2675 MIPS_FPU_EMU_INC_STATS(cmp_sle_d);
2676 break;
2677 case 7:
2678 MIPS_FPU_EMU_INC_STATS(cmp_sule_d);
2679 break;
2680 }
2681 } else {
2682 switch (cmpop) {
2683 case 1:
2684 MIPS_FPU_EMU_INC_STATS(cmp_sor_d);
2685 break;
2686 case 2:
2687 MIPS_FPU_EMU_INC_STATS(cmp_sune_d);
2688 break;
2689 case 3:
2690 MIPS_FPU_EMU_INC_STATS(cmp_sne_d);
2691 break;
2692 }
2693 }
2694 }
2695
2696 /* fmt is l_fmt for double precision so fix it */
2697 rfmt = d_fmt;
2698 /* default to false */
2699 rv.l = 0;
2700
2701 /* CMP.condn.D */
2702 DPFROMREG(fs, MIPSInst_FS(ir));
2703 DPFROMREG(ft, MIPSInst_FT(ir));
2704
2705 /* positive predicates */
2706 if (!(MIPSInst_FUNC(ir) & PREDICATE_BIT)) {
2707 if (ieee754dp_cmp(fs, ft,
2708 cmptab[cmpop], sig))
2709 rv.l = -1LL; /* true, all 1s */
2710 if (sig &&
2711 ieee754_cxtest(IEEE754_INVALID_OPERATION))
2712 rcsr = FPU_CSR_INV_X | FPU_CSR_INV_S;
2713 else
2714 goto copcsr;
2715 } else {
2716 /* negative predicates */
2717 switch (cmpop) {
2718 case 1:
2719 case 2:
2720 case 3:
2721 if (ieee754dp_cmp(fs, ft,
2722 negative_cmptab[cmpop],
2723 sig))
2724 rv.l = -1LL; /* true, all 1s */
2725 if (sig &&
2726 ieee754_cxtest(IEEE754_INVALID_OPERATION))
2727 rcsr = FPU_CSR_INV_X | FPU_CSR_INV_S;
2728 else
2729 goto copcsr;
2730 break;
2731 default:
2732 /* Reserved R6 ops */
2733 return SIGILL;
2734 }
2735 }
2736 break;
2737 }
2738 }
2739 break;
2740
2741 default:
2742 return SIGILL;
2743 }
2744
2745 /*
2746 * Update the fpu CSR register for this operation.
2747 * If an exception is required, generate a tidy SIGFPE exception,
2748 * without updating the result register.
2749 * Note: cause exception bits do not accumulate, they are rewritten
2750 * for each op; only the flag/sticky bits accumulate.
2751 */
2752 ctx->fcr31 = (ctx->fcr31 & ~FPU_CSR_ALL_X) | rcsr;
2753 if ((ctx->fcr31 >> 5) & ctx->fcr31 & FPU_CSR_ALL_E) {
2754 /*printk ("SIGFPE: FPU csr = %08x\n",ctx->fcr31); */
2755 return SIGFPE;
2756 }
2757
2758 /*
2759 * Now we can safely write the result back to the register file.
2760 */
2761 switch (rfmt) {
2762 case -1:
2763
2764 if (cpu_has_mips_4_5_r)
2765 cbit = fpucondbit[MIPSInst_FD(ir) >> 2];
2766 else
2767 cbit = FPU_CSR_COND;
2768 if (rv.w)
2769 ctx->fcr31 |= cbit;
2770 else
2771 ctx->fcr31 &= ~cbit;
2772 break;
2773
2774 case d_fmt:
2775 DPTOREG(rv.d, MIPSInst_FD(ir));
2776 break;
2777 case s_fmt:
2778 SPTOREG(rv.s, MIPSInst_FD(ir));
2779 break;
2780 case w_fmt:
2781 SITOREG(rv.w, MIPSInst_FD(ir));
2782 break;
2783 case l_fmt:
2784 if (!cpu_has_mips_3_4_5_64_r2_r6)
2785 return SIGILL;
2786
2787 DITOREG(rv.l, MIPSInst_FD(ir));
2788 break;
2789 default:
2790 return SIGILL;
2791 }
2792
2793 return 0;
2794}
2795
2796/*
2797 * Emulate FPU instructions.
2798 *
2799 * If we use FPU hardware, then we have been typically called to handle
2800 * an unimplemented operation, such as where an operand is a NaN or
2801 * denormalized. In that case exit the emulation loop after a single
2802 * iteration so as to let hardware execute any subsequent instructions.
2803 *
2804 * If we have no FPU hardware or it has been disabled, then continue
2805 * emulating floating-point instructions until one of these conditions
2806 * has occurred:
2807 *
2808 * - a non-FPU instruction has been encountered,
2809 *
2810 * - an attempt to emulate has ended with a signal,
2811 *
2812 * - the ISA mode has been switched.
2813 *
2814 * We need to terminate the emulation loop if we got switched to the
2815 * MIPS16 mode, whether supported or not, so that we do not attempt
2816 * to emulate a MIPS16 instruction as a regular MIPS FPU instruction.
2817 * Similarly if we got switched to the microMIPS mode and only the
2818 * regular MIPS mode is supported, so that we do not attempt to emulate
2819 * a microMIPS instruction as a regular MIPS FPU instruction. Or if
2820 * we got switched to the regular MIPS mode and only the microMIPS mode
2821 * is supported, so that we do not attempt to emulate a regular MIPS
2822 * instruction that should cause an Address Error exception instead.
2823 * For simplicity we always terminate upon an ISA mode switch.
2824 */
2825int fpu_emulator_cop1Handler(struct pt_regs *xcp, struct mips_fpu_struct *ctx,
2826 int has_fpu, void __user **fault_addr)
2827{
2828 unsigned long oldepc, prevepc;
2829 struct mm_decoded_insn dec_insn;
2830 u16 instr[4];
2831 u16 *instr_ptr;
2832 int sig = 0;
2833
2834 oldepc = xcp->cp0_epc;
2835 do {
2836 prevepc = xcp->cp0_epc;
2837
2838 if (get_isa16_mode(prevepc) && cpu_has_mmips) {
2839 /*
2840 * Get next 2 microMIPS instructions and convert them
2841 * into 32-bit instructions.
2842 */
2843 if ((get_user(instr[0], (u16 __user *)msk_isa16_mode(xcp->cp0_epc))) ||
2844 (get_user(instr[1], (u16 __user *)msk_isa16_mode(xcp->cp0_epc + 2))) ||
2845 (get_user(instr[2], (u16 __user *)msk_isa16_mode(xcp->cp0_epc + 4))) ||
2846 (get_user(instr[3], (u16 __user *)msk_isa16_mode(xcp->cp0_epc + 6)))) {
2847 MIPS_FPU_EMU_INC_STATS(errors);
2848 return SIGBUS;
2849 }
2850 instr_ptr = instr;
2851
2852 /* Get first instruction. */
2853 if (mm_insn_16bit(*instr_ptr)) {
2854 /* Duplicate the half-word. */
2855 dec_insn.insn = (*instr_ptr << 16) |
2856 (*instr_ptr);
2857 /* 16-bit instruction. */
2858 dec_insn.pc_inc = 2;
2859 instr_ptr += 1;
2860 } else {
2861 dec_insn.insn = (*instr_ptr << 16) |
2862 *(instr_ptr+1);
2863 /* 32-bit instruction. */
2864 dec_insn.pc_inc = 4;
2865 instr_ptr += 2;
2866 }
2867 /* Get second instruction. */
2868 if (mm_insn_16bit(*instr_ptr)) {
2869 /* Duplicate the half-word. */
2870 dec_insn.next_insn = (*instr_ptr << 16) |
2871 (*instr_ptr);
2872 /* 16-bit instruction. */
2873 dec_insn.next_pc_inc = 2;
2874 } else {
2875 dec_insn.next_insn = (*instr_ptr << 16) |
2876 *(instr_ptr+1);
2877 /* 32-bit instruction. */
2878 dec_insn.next_pc_inc = 4;
2879 }
2880 dec_insn.micro_mips_mode = 1;
2881 } else {
2882 if ((get_user(dec_insn.insn,
2883 (mips_instruction __user *) xcp->cp0_epc)) ||
2884 (get_user(dec_insn.next_insn,
2885 (mips_instruction __user *)(xcp->cp0_epc+4)))) {
2886 MIPS_FPU_EMU_INC_STATS(errors);
2887 return SIGBUS;
2888 }
2889 dec_insn.pc_inc = 4;
2890 dec_insn.next_pc_inc = 4;
2891 dec_insn.micro_mips_mode = 0;
2892 }
2893
2894 if ((dec_insn.insn == 0) ||
2895 ((dec_insn.pc_inc == 2) &&
2896 ((dec_insn.insn & 0xffff) == MM_NOP16)))
2897 xcp->cp0_epc += dec_insn.pc_inc; /* Skip NOPs */
2898 else {
2899 /*
2900 * The 'ieee754_csr' is an alias of ctx->fcr31.
2901 * No need to copy ctx->fcr31 to ieee754_csr.
2902 */
2903 sig = cop1Emulate(xcp, ctx, dec_insn, fault_addr);
2904 }
2905
2906 if (has_fpu)
2907 break;
2908 if (sig)
2909 break;
2910 /*
2911 * We have to check for the ISA bit explicitly here,
2912 * because `get_isa16_mode' may return 0 if support
2913 * for code compression has been globally disabled,
2914 * or otherwise we may produce the wrong signal or
2915 * even proceed successfully where we must not.
2916 */
2917 if ((xcp->cp0_epc ^ prevepc) & 0x1)
2918 break;
2919
2920 cond_resched();
2921 } while (xcp->cp0_epc > prevepc);
2922
2923 /* SIGILL indicates a non-fpu instruction */
2924 if (sig == SIGILL && xcp->cp0_epc != oldepc)
2925 /* but if EPC has advanced, then ignore it */
2926 sig = 0;
2927
2928 return sig;
2929}
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/uaccess.h>
49#include <asm/branch.h>
50
51#include "ieee754.h"
52
53/* Strap kernel emulator for full MIPS IV emulation */
54
55#ifdef __mips
56#undef __mips
57#endif
58#define __mips 4
59
60/* Function which emulates a floating point instruction. */
61
62static int fpu_emu(struct pt_regs *, struct mips_fpu_struct *,
63 mips_instruction);
64
65#if __mips >= 4 && __mips != 32
66static int fpux_emu(struct pt_regs *,
67 struct mips_fpu_struct *, mips_instruction, void *__user *);
68#endif
69
70/* Further private data for which no space exists in mips_fpu_struct */
71
72#ifdef CONFIG_DEBUG_FS
73DEFINE_PER_CPU(struct mips_fpu_emulator_stats, fpuemustats);
74#endif
75
76/* Control registers */
77
78#define FPCREG_RID 0 /* $0 = revision id */
79#define FPCREG_CSR 31 /* $31 = csr */
80
81/* Determine rounding mode from the RM bits of the FCSR */
82#define modeindex(v) ((v) & FPU_CSR_RM)
83
84/* Convert Mips rounding mode (0..3) to IEEE library modes. */
85static const unsigned char ieee_rm[4] = {
86 [FPU_CSR_RN] = IEEE754_RN,
87 [FPU_CSR_RZ] = IEEE754_RZ,
88 [FPU_CSR_RU] = IEEE754_RU,
89 [FPU_CSR_RD] = IEEE754_RD,
90};
91/* Convert IEEE library modes to Mips rounding mode (0..3). */
92static const unsigned char mips_rm[4] = {
93 [IEEE754_RN] = FPU_CSR_RN,
94 [IEEE754_RZ] = FPU_CSR_RZ,
95 [IEEE754_RD] = FPU_CSR_RD,
96 [IEEE754_RU] = FPU_CSR_RU,
97};
98
99#if __mips >= 4
100/* convert condition code register number to csr bit */
101static const unsigned int fpucondbit[8] = {
102 FPU_CSR_COND0,
103 FPU_CSR_COND1,
104 FPU_CSR_COND2,
105 FPU_CSR_COND3,
106 FPU_CSR_COND4,
107 FPU_CSR_COND5,
108 FPU_CSR_COND6,
109 FPU_CSR_COND7
110};
111#endif
112
113
114/*
115 * Redundant with logic already in kernel/branch.c,
116 * embedded in compute_return_epc. At some point,
117 * a single subroutine should be used across both
118 * modules.
119 */
120static int isBranchInstr(mips_instruction * i)
121{
122 switch (MIPSInst_OPCODE(*i)) {
123 case spec_op:
124 switch (MIPSInst_FUNC(*i)) {
125 case jalr_op:
126 case jr_op:
127 return 1;
128 }
129 break;
130
131 case bcond_op:
132 switch (MIPSInst_RT(*i)) {
133 case bltz_op:
134 case bgez_op:
135 case bltzl_op:
136 case bgezl_op:
137 case bltzal_op:
138 case bgezal_op:
139 case bltzall_op:
140 case bgezall_op:
141 return 1;
142 }
143 break;
144
145 case j_op:
146 case jal_op:
147 case jalx_op:
148 case beq_op:
149 case bne_op:
150 case blez_op:
151 case bgtz_op:
152 case beql_op:
153 case bnel_op:
154 case blezl_op:
155 case bgtzl_op:
156 return 1;
157
158 case cop0_op:
159 case cop1_op:
160 case cop2_op:
161 case cop1x_op:
162 if (MIPSInst_RS(*i) == bc_op)
163 return 1;
164 break;
165 }
166
167 return 0;
168}
169
170/*
171 * In the Linux kernel, we support selection of FPR format on the
172 * basis of the Status.FR bit. If an FPU is not present, the FR bit
173 * is hardwired to zero, which would imply a 32-bit FPU even for
174 * 64-bit CPUs. For 64-bit kernels with no FPU we use TIF_32BIT_REGS
175 * as a proxy for the FR bit so that a 64-bit FPU is emulated. In any
176 * case, for a 32-bit kernel which uses the O32 MIPS ABI, only the
177 * even FPRs are used (Status.FR = 0).
178 */
179static inline int cop1_64bit(struct pt_regs *xcp)
180{
181 if (cpu_has_fpu)
182 return xcp->cp0_status & ST0_FR;
183#ifdef CONFIG_64BIT
184 return !test_thread_flag(TIF_32BIT_REGS);
185#else
186 return 0;
187#endif
188}
189
190#define SIFROMREG(si, x) ((si) = cop1_64bit(xcp) || !(x & 1) ? \
191 (int)ctx->fpr[x] : (int)(ctx->fpr[x & ~1] >> 32))
192
193#define SITOREG(si, x) (ctx->fpr[x & ~(cop1_64bit(xcp) == 0)] = \
194 cop1_64bit(xcp) || !(x & 1) ? \
195 ctx->fpr[x & ~1] >> 32 << 32 | (u32)(si) : \
196 ctx->fpr[x & ~1] << 32 >> 32 | (u64)(si) << 32)
197
198#define DIFROMREG(di, x) ((di) = ctx->fpr[x & ~(cop1_64bit(xcp) == 0)])
199#define DITOREG(di, x) (ctx->fpr[x & ~(cop1_64bit(xcp) == 0)] = (di))
200
201#define SPFROMREG(sp, x) SIFROMREG((sp).bits, x)
202#define SPTOREG(sp, x) SITOREG((sp).bits, x)
203#define DPFROMREG(dp, x) DIFROMREG((dp).bits, x)
204#define DPTOREG(dp, x) DITOREG((dp).bits, x)
205
206/*
207 * Emulate the single floating point instruction pointed at by EPC.
208 * Two instructions if the instruction is in a branch delay slot.
209 */
210
211static int cop1Emulate(struct pt_regs *xcp, struct mips_fpu_struct *ctx,
212 void *__user *fault_addr)
213{
214 mips_instruction ir;
215 unsigned long emulpc, contpc;
216 unsigned int cond;
217
218 if (!access_ok(VERIFY_READ, xcp->cp0_epc, sizeof(mips_instruction))) {
219 MIPS_FPU_EMU_INC_STATS(errors);
220 *fault_addr = (mips_instruction __user *)xcp->cp0_epc;
221 return SIGBUS;
222 }
223 if (__get_user(ir, (mips_instruction __user *) xcp->cp0_epc)) {
224 MIPS_FPU_EMU_INC_STATS(errors);
225 *fault_addr = (mips_instruction __user *)xcp->cp0_epc;
226 return SIGSEGV;
227 }
228
229 /* XXX NEC Vr54xx bug workaround */
230 if ((xcp->cp0_cause & CAUSEF_BD) && !isBranchInstr(&ir))
231 xcp->cp0_cause &= ~CAUSEF_BD;
232
233 if (xcp->cp0_cause & CAUSEF_BD) {
234 /*
235 * The instruction to be emulated is in a branch delay slot
236 * which means that we have to emulate the branch instruction
237 * BEFORE we do the cop1 instruction.
238 *
239 * This branch could be a COP1 branch, but in that case we
240 * would have had a trap for that instruction, and would not
241 * come through this route.
242 *
243 * Linux MIPS branch emulator operates on context, updating the
244 * cp0_epc.
245 */
246 emulpc = xcp->cp0_epc + 4; /* Snapshot emulation target */
247
248 if (__compute_return_epc(xcp)) {
249#ifdef CP1DBG
250 printk("failed to emulate branch at %p\n",
251 (void *) (xcp->cp0_epc));
252#endif
253 return SIGILL;
254 }
255 if (!access_ok(VERIFY_READ, emulpc, sizeof(mips_instruction))) {
256 MIPS_FPU_EMU_INC_STATS(errors);
257 *fault_addr = (mips_instruction __user *)emulpc;
258 return SIGBUS;
259 }
260 if (__get_user(ir, (mips_instruction __user *) emulpc)) {
261 MIPS_FPU_EMU_INC_STATS(errors);
262 *fault_addr = (mips_instruction __user *)emulpc;
263 return SIGSEGV;
264 }
265 /* __compute_return_epc() will have updated cp0_epc */
266 contpc = xcp->cp0_epc;
267 /* In order not to confuse ptrace() et al, tweak context */
268 xcp->cp0_epc = emulpc - 4;
269 } else {
270 emulpc = xcp->cp0_epc;
271 contpc = xcp->cp0_epc + 4;
272 }
273
274 emul:
275 perf_sw_event(PERF_COUNT_SW_EMULATION_FAULTS, 1, xcp, 0);
276 MIPS_FPU_EMU_INC_STATS(emulated);
277 switch (MIPSInst_OPCODE(ir)) {
278 case ldc1_op:{
279 u64 __user *va = (u64 __user *) (xcp->regs[MIPSInst_RS(ir)] +
280 MIPSInst_SIMM(ir));
281 u64 val;
282
283 MIPS_FPU_EMU_INC_STATS(loads);
284
285 if (!access_ok(VERIFY_READ, va, sizeof(u64))) {
286 MIPS_FPU_EMU_INC_STATS(errors);
287 *fault_addr = va;
288 return SIGBUS;
289 }
290 if (__get_user(val, va)) {
291 MIPS_FPU_EMU_INC_STATS(errors);
292 *fault_addr = va;
293 return SIGSEGV;
294 }
295 DITOREG(val, MIPSInst_RT(ir));
296 break;
297 }
298
299 case sdc1_op:{
300 u64 __user *va = (u64 __user *) (xcp->regs[MIPSInst_RS(ir)] +
301 MIPSInst_SIMM(ir));
302 u64 val;
303
304 MIPS_FPU_EMU_INC_STATS(stores);
305 DIFROMREG(val, MIPSInst_RT(ir));
306 if (!access_ok(VERIFY_WRITE, va, sizeof(u64))) {
307 MIPS_FPU_EMU_INC_STATS(errors);
308 *fault_addr = va;
309 return SIGBUS;
310 }
311 if (__put_user(val, va)) {
312 MIPS_FPU_EMU_INC_STATS(errors);
313 *fault_addr = va;
314 return SIGSEGV;
315 }
316 break;
317 }
318
319 case lwc1_op:{
320 u32 __user *va = (u32 __user *) (xcp->regs[MIPSInst_RS(ir)] +
321 MIPSInst_SIMM(ir));
322 u32 val;
323
324 MIPS_FPU_EMU_INC_STATS(loads);
325 if (!access_ok(VERIFY_READ, va, sizeof(u32))) {
326 MIPS_FPU_EMU_INC_STATS(errors);
327 *fault_addr = va;
328 return SIGBUS;
329 }
330 if (__get_user(val, va)) {
331 MIPS_FPU_EMU_INC_STATS(errors);
332 *fault_addr = va;
333 return SIGSEGV;
334 }
335 SITOREG(val, MIPSInst_RT(ir));
336 break;
337 }
338
339 case swc1_op:{
340 u32 __user *va = (u32 __user *) (xcp->regs[MIPSInst_RS(ir)] +
341 MIPSInst_SIMM(ir));
342 u32 val;
343
344 MIPS_FPU_EMU_INC_STATS(stores);
345 SIFROMREG(val, MIPSInst_RT(ir));
346 if (!access_ok(VERIFY_WRITE, va, sizeof(u32))) {
347 MIPS_FPU_EMU_INC_STATS(errors);
348 *fault_addr = va;
349 return SIGBUS;
350 }
351 if (__put_user(val, va)) {
352 MIPS_FPU_EMU_INC_STATS(errors);
353 *fault_addr = va;
354 return SIGSEGV;
355 }
356 break;
357 }
358
359 case cop1_op:
360 switch (MIPSInst_RS(ir)) {
361
362#if defined(__mips64)
363 case dmfc_op:
364 /* copregister fs -> gpr[rt] */
365 if (MIPSInst_RT(ir) != 0) {
366 DIFROMREG(xcp->regs[MIPSInst_RT(ir)],
367 MIPSInst_RD(ir));
368 }
369 break;
370
371 case dmtc_op:
372 /* copregister fs <- rt */
373 DITOREG(xcp->regs[MIPSInst_RT(ir)], MIPSInst_RD(ir));
374 break;
375#endif
376
377 case mfc_op:
378 /* copregister rd -> gpr[rt] */
379 if (MIPSInst_RT(ir) != 0) {
380 SIFROMREG(xcp->regs[MIPSInst_RT(ir)],
381 MIPSInst_RD(ir));
382 }
383 break;
384
385 case mtc_op:
386 /* copregister rd <- rt */
387 SITOREG(xcp->regs[MIPSInst_RT(ir)], MIPSInst_RD(ir));
388 break;
389
390 case cfc_op:{
391 /* cop control register rd -> gpr[rt] */
392 u32 value;
393
394 if (MIPSInst_RD(ir) == FPCREG_CSR) {
395 value = ctx->fcr31;
396 value = (value & ~FPU_CSR_RM) |
397 mips_rm[modeindex(value)];
398#ifdef CSRTRACE
399 printk("%p gpr[%d]<-csr=%08x\n",
400 (void *) (xcp->cp0_epc),
401 MIPSInst_RT(ir), value);
402#endif
403 }
404 else if (MIPSInst_RD(ir) == FPCREG_RID)
405 value = 0;
406 else
407 value = 0;
408 if (MIPSInst_RT(ir))
409 xcp->regs[MIPSInst_RT(ir)] = value;
410 break;
411 }
412
413 case ctc_op:{
414 /* copregister rd <- rt */
415 u32 value;
416
417 if (MIPSInst_RT(ir) == 0)
418 value = 0;
419 else
420 value = xcp->regs[MIPSInst_RT(ir)];
421
422 /* we only have one writable control reg
423 */
424 if (MIPSInst_RD(ir) == FPCREG_CSR) {
425#ifdef CSRTRACE
426 printk("%p gpr[%d]->csr=%08x\n",
427 (void *) (xcp->cp0_epc),
428 MIPSInst_RT(ir), value);
429#endif
430
431 /*
432 * Don't write reserved bits,
433 * and convert to ieee library modes
434 */
435 ctx->fcr31 = (value &
436 ~(FPU_CSR_RSVD | FPU_CSR_RM)) |
437 ieee_rm[modeindex(value)];
438 }
439 if ((ctx->fcr31 >> 5) & ctx->fcr31 & FPU_CSR_ALL_E) {
440 return SIGFPE;
441 }
442 break;
443 }
444
445 case bc_op:{
446 int likely = 0;
447
448 if (xcp->cp0_cause & CAUSEF_BD)
449 return SIGILL;
450
451#if __mips >= 4
452 cond = ctx->fcr31 & fpucondbit[MIPSInst_RT(ir) >> 2];
453#else
454 cond = ctx->fcr31 & FPU_CSR_COND;
455#endif
456 switch (MIPSInst_RT(ir) & 3) {
457 case bcfl_op:
458 likely = 1;
459 case bcf_op:
460 cond = !cond;
461 break;
462 case bctl_op:
463 likely = 1;
464 case bct_op:
465 break;
466 default:
467 /* thats an illegal instruction */
468 return SIGILL;
469 }
470
471 xcp->cp0_cause |= CAUSEF_BD;
472 if (cond) {
473 /* branch taken: emulate dslot
474 * instruction
475 */
476 xcp->cp0_epc += 4;
477 contpc = (xcp->cp0_epc +
478 (MIPSInst_SIMM(ir) << 2));
479
480 if (!access_ok(VERIFY_READ, xcp->cp0_epc,
481 sizeof(mips_instruction))) {
482 MIPS_FPU_EMU_INC_STATS(errors);
483 *fault_addr = (mips_instruction __user *)xcp->cp0_epc;
484 return SIGBUS;
485 }
486 if (__get_user(ir,
487 (mips_instruction __user *) xcp->cp0_epc)) {
488 MIPS_FPU_EMU_INC_STATS(errors);
489 *fault_addr = (mips_instruction __user *)xcp->cp0_epc;
490 return SIGSEGV;
491 }
492
493 switch (MIPSInst_OPCODE(ir)) {
494 case lwc1_op:
495 case swc1_op:
496#if (__mips >= 2 || defined(__mips64))
497 case ldc1_op:
498 case sdc1_op:
499#endif
500 case cop1_op:
501#if __mips >= 4 && __mips != 32
502 case cop1x_op:
503#endif
504 /* its one of ours */
505 goto emul;
506#if __mips >= 4
507 case spec_op:
508 if (MIPSInst_FUNC(ir) == movc_op)
509 goto emul;
510 break;
511#endif
512 }
513
514 /*
515 * Single step the non-cp1
516 * instruction in the dslot
517 */
518 return mips_dsemul(xcp, ir, contpc);
519 }
520 else {
521 /* branch not taken */
522 if (likely) {
523 /*
524 * branch likely nullifies
525 * dslot if not taken
526 */
527 xcp->cp0_epc += 4;
528 contpc += 4;
529 /*
530 * else continue & execute
531 * dslot as normal insn
532 */
533 }
534 }
535 break;
536 }
537
538 default:
539 if (!(MIPSInst_RS(ir) & 0x10))
540 return SIGILL;
541 {
542 int sig;
543
544 /* a real fpu computation instruction */
545 if ((sig = fpu_emu(xcp, ctx, ir)))
546 return sig;
547 }
548 }
549 break;
550
551#if __mips >= 4 && __mips != 32
552 case cop1x_op:{
553 int sig = fpux_emu(xcp, ctx, ir, fault_addr);
554 if (sig)
555 return sig;
556 break;
557 }
558#endif
559
560#if __mips >= 4
561 case spec_op:
562 if (MIPSInst_FUNC(ir) != movc_op)
563 return SIGILL;
564 cond = fpucondbit[MIPSInst_RT(ir) >> 2];
565 if (((ctx->fcr31 & cond) != 0) == ((MIPSInst_RT(ir) & 1) != 0))
566 xcp->regs[MIPSInst_RD(ir)] =
567 xcp->regs[MIPSInst_RS(ir)];
568 break;
569#endif
570
571 default:
572 return SIGILL;
573 }
574
575 /* we did it !! */
576 xcp->cp0_epc = contpc;
577 xcp->cp0_cause &= ~CAUSEF_BD;
578
579 return 0;
580}
581
582/*
583 * Conversion table from MIPS compare ops 48-63
584 * cond = ieee754dp_cmp(x,y,IEEE754_UN,sig);
585 */
586static const unsigned char cmptab[8] = {
587 0, /* cmp_0 (sig) cmp_sf */
588 IEEE754_CUN, /* cmp_un (sig) cmp_ngle */
589 IEEE754_CEQ, /* cmp_eq (sig) cmp_seq */
590 IEEE754_CEQ | IEEE754_CUN, /* cmp_ueq (sig) cmp_ngl */
591 IEEE754_CLT, /* cmp_olt (sig) cmp_lt */
592 IEEE754_CLT | IEEE754_CUN, /* cmp_ult (sig) cmp_nge */
593 IEEE754_CLT | IEEE754_CEQ, /* cmp_ole (sig) cmp_le */
594 IEEE754_CLT | IEEE754_CEQ | IEEE754_CUN, /* cmp_ule (sig) cmp_ngt */
595};
596
597
598#if __mips >= 4 && __mips != 32
599
600/*
601 * Additional MIPS4 instructions
602 */
603
604#define DEF3OP(name, p, f1, f2, f3) \
605static ieee754##p fpemu_##p##_##name(ieee754##p r, ieee754##p s, \
606 ieee754##p t) \
607{ \
608 struct _ieee754_csr ieee754_csr_save; \
609 s = f1(s, t); \
610 ieee754_csr_save = ieee754_csr; \
611 s = f2(s, r); \
612 ieee754_csr_save.cx |= ieee754_csr.cx; \
613 ieee754_csr_save.sx |= ieee754_csr.sx; \
614 s = f3(s); \
615 ieee754_csr.cx |= ieee754_csr_save.cx; \
616 ieee754_csr.sx |= ieee754_csr_save.sx; \
617 return s; \
618}
619
620static ieee754dp fpemu_dp_recip(ieee754dp d)
621{
622 return ieee754dp_div(ieee754dp_one(0), d);
623}
624
625static ieee754dp fpemu_dp_rsqrt(ieee754dp d)
626{
627 return ieee754dp_div(ieee754dp_one(0), ieee754dp_sqrt(d));
628}
629
630static ieee754sp fpemu_sp_recip(ieee754sp s)
631{
632 return ieee754sp_div(ieee754sp_one(0), s);
633}
634
635static ieee754sp fpemu_sp_rsqrt(ieee754sp s)
636{
637 return ieee754sp_div(ieee754sp_one(0), ieee754sp_sqrt(s));
638}
639
640DEF3OP(madd, sp, ieee754sp_mul, ieee754sp_add, );
641DEF3OP(msub, sp, ieee754sp_mul, ieee754sp_sub, );
642DEF3OP(nmadd, sp, ieee754sp_mul, ieee754sp_add, ieee754sp_neg);
643DEF3OP(nmsub, sp, ieee754sp_mul, ieee754sp_sub, ieee754sp_neg);
644DEF3OP(madd, dp, ieee754dp_mul, ieee754dp_add, );
645DEF3OP(msub, dp, ieee754dp_mul, ieee754dp_sub, );
646DEF3OP(nmadd, dp, ieee754dp_mul, ieee754dp_add, ieee754dp_neg);
647DEF3OP(nmsub, dp, ieee754dp_mul, ieee754dp_sub, ieee754dp_neg);
648
649static int fpux_emu(struct pt_regs *xcp, struct mips_fpu_struct *ctx,
650 mips_instruction ir, void *__user *fault_addr)
651{
652 unsigned rcsr = 0; /* resulting csr */
653
654 MIPS_FPU_EMU_INC_STATS(cp1xops);
655
656 switch (MIPSInst_FMA_FFMT(ir)) {
657 case s_fmt:{ /* 0 */
658
659 ieee754sp(*handler) (ieee754sp, ieee754sp, ieee754sp);
660 ieee754sp fd, fr, fs, ft;
661 u32 __user *va;
662 u32 val;
663
664 switch (MIPSInst_FUNC(ir)) {
665 case lwxc1_op:
666 va = (void __user *) (xcp->regs[MIPSInst_FR(ir)] +
667 xcp->regs[MIPSInst_FT(ir)]);
668
669 MIPS_FPU_EMU_INC_STATS(loads);
670 if (!access_ok(VERIFY_READ, va, sizeof(u32))) {
671 MIPS_FPU_EMU_INC_STATS(errors);
672 *fault_addr = va;
673 return SIGBUS;
674 }
675 if (__get_user(val, va)) {
676 MIPS_FPU_EMU_INC_STATS(errors);
677 *fault_addr = va;
678 return SIGSEGV;
679 }
680 SITOREG(val, MIPSInst_FD(ir));
681 break;
682
683 case swxc1_op:
684 va = (void __user *) (xcp->regs[MIPSInst_FR(ir)] +
685 xcp->regs[MIPSInst_FT(ir)]);
686
687 MIPS_FPU_EMU_INC_STATS(stores);
688
689 SIFROMREG(val, MIPSInst_FS(ir));
690 if (!access_ok(VERIFY_WRITE, va, sizeof(u32))) {
691 MIPS_FPU_EMU_INC_STATS(errors);
692 *fault_addr = va;
693 return SIGBUS;
694 }
695 if (put_user(val, va)) {
696 MIPS_FPU_EMU_INC_STATS(errors);
697 *fault_addr = va;
698 return SIGSEGV;
699 }
700 break;
701
702 case madd_s_op:
703 handler = fpemu_sp_madd;
704 goto scoptop;
705 case msub_s_op:
706 handler = fpemu_sp_msub;
707 goto scoptop;
708 case nmadd_s_op:
709 handler = fpemu_sp_nmadd;
710 goto scoptop;
711 case nmsub_s_op:
712 handler = fpemu_sp_nmsub;
713 goto scoptop;
714
715 scoptop:
716 SPFROMREG(fr, MIPSInst_FR(ir));
717 SPFROMREG(fs, MIPSInst_FS(ir));
718 SPFROMREG(ft, MIPSInst_FT(ir));
719 fd = (*handler) (fr, fs, ft);
720 SPTOREG(fd, MIPSInst_FD(ir));
721
722 copcsr:
723 if (ieee754_cxtest(IEEE754_INEXACT))
724 rcsr |= FPU_CSR_INE_X | FPU_CSR_INE_S;
725 if (ieee754_cxtest(IEEE754_UNDERFLOW))
726 rcsr |= FPU_CSR_UDF_X | FPU_CSR_UDF_S;
727 if (ieee754_cxtest(IEEE754_OVERFLOW))
728 rcsr |= FPU_CSR_OVF_X | FPU_CSR_OVF_S;
729 if (ieee754_cxtest(IEEE754_INVALID_OPERATION))
730 rcsr |= FPU_CSR_INV_X | FPU_CSR_INV_S;
731
732 ctx->fcr31 = (ctx->fcr31 & ~FPU_CSR_ALL_X) | rcsr;
733 if ((ctx->fcr31 >> 5) & ctx->fcr31 & FPU_CSR_ALL_E) {
734 /*printk ("SIGFPE: fpu csr = %08x\n",
735 ctx->fcr31); */
736 return SIGFPE;
737 }
738
739 break;
740
741 default:
742 return SIGILL;
743 }
744 break;
745 }
746
747 case d_fmt:{ /* 1 */
748 ieee754dp(*handler) (ieee754dp, ieee754dp, ieee754dp);
749 ieee754dp fd, fr, fs, ft;
750 u64 __user *va;
751 u64 val;
752
753 switch (MIPSInst_FUNC(ir)) {
754 case ldxc1_op:
755 va = (void __user *) (xcp->regs[MIPSInst_FR(ir)] +
756 xcp->regs[MIPSInst_FT(ir)]);
757
758 MIPS_FPU_EMU_INC_STATS(loads);
759 if (!access_ok(VERIFY_READ, va, sizeof(u64))) {
760 MIPS_FPU_EMU_INC_STATS(errors);
761 *fault_addr = va;
762 return SIGBUS;
763 }
764 if (__get_user(val, va)) {
765 MIPS_FPU_EMU_INC_STATS(errors);
766 *fault_addr = va;
767 return SIGSEGV;
768 }
769 DITOREG(val, MIPSInst_FD(ir));
770 break;
771
772 case sdxc1_op:
773 va = (void __user *) (xcp->regs[MIPSInst_FR(ir)] +
774 xcp->regs[MIPSInst_FT(ir)]);
775
776 MIPS_FPU_EMU_INC_STATS(stores);
777 DIFROMREG(val, MIPSInst_FS(ir));
778 if (!access_ok(VERIFY_WRITE, va, sizeof(u64))) {
779 MIPS_FPU_EMU_INC_STATS(errors);
780 *fault_addr = va;
781 return SIGBUS;
782 }
783 if (__put_user(val, va)) {
784 MIPS_FPU_EMU_INC_STATS(errors);
785 *fault_addr = va;
786 return SIGSEGV;
787 }
788 break;
789
790 case madd_d_op:
791 handler = fpemu_dp_madd;
792 goto dcoptop;
793 case msub_d_op:
794 handler = fpemu_dp_msub;
795 goto dcoptop;
796 case nmadd_d_op:
797 handler = fpemu_dp_nmadd;
798 goto dcoptop;
799 case nmsub_d_op:
800 handler = fpemu_dp_nmsub;
801 goto dcoptop;
802
803 dcoptop:
804 DPFROMREG(fr, MIPSInst_FR(ir));
805 DPFROMREG(fs, MIPSInst_FS(ir));
806 DPFROMREG(ft, MIPSInst_FT(ir));
807 fd = (*handler) (fr, fs, ft);
808 DPTOREG(fd, MIPSInst_FD(ir));
809 goto copcsr;
810
811 default:
812 return SIGILL;
813 }
814 break;
815 }
816
817 case 0x7: /* 7 */
818 if (MIPSInst_FUNC(ir) != pfetch_op) {
819 return SIGILL;
820 }
821 /* ignore prefx operation */
822 break;
823
824 default:
825 return SIGILL;
826 }
827
828 return 0;
829}
830#endif
831
832
833
834/*
835 * Emulate a single COP1 arithmetic instruction.
836 */
837static int fpu_emu(struct pt_regs *xcp, struct mips_fpu_struct *ctx,
838 mips_instruction ir)
839{
840 int rfmt; /* resulting format */
841 unsigned rcsr = 0; /* resulting csr */
842 unsigned cond;
843 union {
844 ieee754dp d;
845 ieee754sp s;
846 int w;
847#ifdef __mips64
848 s64 l;
849#endif
850 } rv; /* resulting value */
851
852 MIPS_FPU_EMU_INC_STATS(cp1ops);
853 switch (rfmt = (MIPSInst_FFMT(ir) & 0xf)) {
854 case s_fmt:{ /* 0 */
855 union {
856 ieee754sp(*b) (ieee754sp, ieee754sp);
857 ieee754sp(*u) (ieee754sp);
858 } handler;
859
860 switch (MIPSInst_FUNC(ir)) {
861 /* binary ops */
862 case fadd_op:
863 handler.b = ieee754sp_add;
864 goto scopbop;
865 case fsub_op:
866 handler.b = ieee754sp_sub;
867 goto scopbop;
868 case fmul_op:
869 handler.b = ieee754sp_mul;
870 goto scopbop;
871 case fdiv_op:
872 handler.b = ieee754sp_div;
873 goto scopbop;
874
875 /* unary ops */
876#if __mips >= 2 || defined(__mips64)
877 case fsqrt_op:
878 handler.u = ieee754sp_sqrt;
879 goto scopuop;
880#endif
881#if __mips >= 4 && __mips != 32
882 case frsqrt_op:
883 handler.u = fpemu_sp_rsqrt;
884 goto scopuop;
885 case frecip_op:
886 handler.u = fpemu_sp_recip;
887 goto scopuop;
888#endif
889#if __mips >= 4
890 case fmovc_op:
891 cond = fpucondbit[MIPSInst_FT(ir) >> 2];
892 if (((ctx->fcr31 & cond) != 0) !=
893 ((MIPSInst_FT(ir) & 1) != 0))
894 return 0;
895 SPFROMREG(rv.s, MIPSInst_FS(ir));
896 break;
897 case fmovz_op:
898 if (xcp->regs[MIPSInst_FT(ir)] != 0)
899 return 0;
900 SPFROMREG(rv.s, MIPSInst_FS(ir));
901 break;
902 case fmovn_op:
903 if (xcp->regs[MIPSInst_FT(ir)] == 0)
904 return 0;
905 SPFROMREG(rv.s, MIPSInst_FS(ir));
906 break;
907#endif
908 case fabs_op:
909 handler.u = ieee754sp_abs;
910 goto scopuop;
911 case fneg_op:
912 handler.u = ieee754sp_neg;
913 goto scopuop;
914 case fmov_op:
915 /* an easy one */
916 SPFROMREG(rv.s, MIPSInst_FS(ir));
917 goto copcsr;
918
919 /* binary op on handler */
920 scopbop:
921 {
922 ieee754sp fs, ft;
923
924 SPFROMREG(fs, MIPSInst_FS(ir));
925 SPFROMREG(ft, MIPSInst_FT(ir));
926
927 rv.s = (*handler.b) (fs, ft);
928 goto copcsr;
929 }
930 scopuop:
931 {
932 ieee754sp fs;
933
934 SPFROMREG(fs, MIPSInst_FS(ir));
935 rv.s = (*handler.u) (fs);
936 goto copcsr;
937 }
938 copcsr:
939 if (ieee754_cxtest(IEEE754_INEXACT))
940 rcsr |= FPU_CSR_INE_X | FPU_CSR_INE_S;
941 if (ieee754_cxtest(IEEE754_UNDERFLOW))
942 rcsr |= FPU_CSR_UDF_X | FPU_CSR_UDF_S;
943 if (ieee754_cxtest(IEEE754_OVERFLOW))
944 rcsr |= FPU_CSR_OVF_X | FPU_CSR_OVF_S;
945 if (ieee754_cxtest(IEEE754_ZERO_DIVIDE))
946 rcsr |= FPU_CSR_DIV_X | FPU_CSR_DIV_S;
947 if (ieee754_cxtest(IEEE754_INVALID_OPERATION))
948 rcsr |= FPU_CSR_INV_X | FPU_CSR_INV_S;
949 break;
950
951 /* unary conv ops */
952 case fcvts_op:
953 return SIGILL; /* not defined */
954 case fcvtd_op:{
955 ieee754sp fs;
956
957 SPFROMREG(fs, MIPSInst_FS(ir));
958 rv.d = ieee754dp_fsp(fs);
959 rfmt = d_fmt;
960 goto copcsr;
961 }
962 case fcvtw_op:{
963 ieee754sp fs;
964
965 SPFROMREG(fs, MIPSInst_FS(ir));
966 rv.w = ieee754sp_tint(fs);
967 rfmt = w_fmt;
968 goto copcsr;
969 }
970
971#if __mips >= 2 || defined(__mips64)
972 case fround_op:
973 case ftrunc_op:
974 case fceil_op:
975 case ffloor_op:{
976 unsigned int oldrm = ieee754_csr.rm;
977 ieee754sp fs;
978
979 SPFROMREG(fs, MIPSInst_FS(ir));
980 ieee754_csr.rm = ieee_rm[modeindex(MIPSInst_FUNC(ir))];
981 rv.w = ieee754sp_tint(fs);
982 ieee754_csr.rm = oldrm;
983 rfmt = w_fmt;
984 goto copcsr;
985 }
986#endif /* __mips >= 2 */
987
988#if defined(__mips64)
989 case fcvtl_op:{
990 ieee754sp fs;
991
992 SPFROMREG(fs, MIPSInst_FS(ir));
993 rv.l = ieee754sp_tlong(fs);
994 rfmt = l_fmt;
995 goto copcsr;
996 }
997
998 case froundl_op:
999 case ftruncl_op:
1000 case fceill_op:
1001 case ffloorl_op:{
1002 unsigned int oldrm = ieee754_csr.rm;
1003 ieee754sp fs;
1004
1005 SPFROMREG(fs, MIPSInst_FS(ir));
1006 ieee754_csr.rm = ieee_rm[modeindex(MIPSInst_FUNC(ir))];
1007 rv.l = ieee754sp_tlong(fs);
1008 ieee754_csr.rm = oldrm;
1009 rfmt = l_fmt;
1010 goto copcsr;
1011 }
1012#endif /* defined(__mips64) */
1013
1014 default:
1015 if (MIPSInst_FUNC(ir) >= fcmp_op) {
1016 unsigned cmpop = MIPSInst_FUNC(ir) - fcmp_op;
1017 ieee754sp fs, ft;
1018
1019 SPFROMREG(fs, MIPSInst_FS(ir));
1020 SPFROMREG(ft, MIPSInst_FT(ir));
1021 rv.w = ieee754sp_cmp(fs, ft,
1022 cmptab[cmpop & 0x7], cmpop & 0x8);
1023 rfmt = -1;
1024 if ((cmpop & 0x8) && ieee754_cxtest
1025 (IEEE754_INVALID_OPERATION))
1026 rcsr = FPU_CSR_INV_X | FPU_CSR_INV_S;
1027 else
1028 goto copcsr;
1029
1030 }
1031 else {
1032 return SIGILL;
1033 }
1034 break;
1035 }
1036 break;
1037 }
1038
1039 case d_fmt:{
1040 union {
1041 ieee754dp(*b) (ieee754dp, ieee754dp);
1042 ieee754dp(*u) (ieee754dp);
1043 } handler;
1044
1045 switch (MIPSInst_FUNC(ir)) {
1046 /* binary ops */
1047 case fadd_op:
1048 handler.b = ieee754dp_add;
1049 goto dcopbop;
1050 case fsub_op:
1051 handler.b = ieee754dp_sub;
1052 goto dcopbop;
1053 case fmul_op:
1054 handler.b = ieee754dp_mul;
1055 goto dcopbop;
1056 case fdiv_op:
1057 handler.b = ieee754dp_div;
1058 goto dcopbop;
1059
1060 /* unary ops */
1061#if __mips >= 2 || defined(__mips64)
1062 case fsqrt_op:
1063 handler.u = ieee754dp_sqrt;
1064 goto dcopuop;
1065#endif
1066#if __mips >= 4 && __mips != 32
1067 case frsqrt_op:
1068 handler.u = fpemu_dp_rsqrt;
1069 goto dcopuop;
1070 case frecip_op:
1071 handler.u = fpemu_dp_recip;
1072 goto dcopuop;
1073#endif
1074#if __mips >= 4
1075 case fmovc_op:
1076 cond = fpucondbit[MIPSInst_FT(ir) >> 2];
1077 if (((ctx->fcr31 & cond) != 0) !=
1078 ((MIPSInst_FT(ir) & 1) != 0))
1079 return 0;
1080 DPFROMREG(rv.d, MIPSInst_FS(ir));
1081 break;
1082 case fmovz_op:
1083 if (xcp->regs[MIPSInst_FT(ir)] != 0)
1084 return 0;
1085 DPFROMREG(rv.d, MIPSInst_FS(ir));
1086 break;
1087 case fmovn_op:
1088 if (xcp->regs[MIPSInst_FT(ir)] == 0)
1089 return 0;
1090 DPFROMREG(rv.d, MIPSInst_FS(ir));
1091 break;
1092#endif
1093 case fabs_op:
1094 handler.u = ieee754dp_abs;
1095 goto dcopuop;
1096
1097 case fneg_op:
1098 handler.u = ieee754dp_neg;
1099 goto dcopuop;
1100
1101 case fmov_op:
1102 /* an easy one */
1103 DPFROMREG(rv.d, MIPSInst_FS(ir));
1104 goto copcsr;
1105
1106 /* binary op on handler */
1107 dcopbop:{
1108 ieee754dp fs, ft;
1109
1110 DPFROMREG(fs, MIPSInst_FS(ir));
1111 DPFROMREG(ft, MIPSInst_FT(ir));
1112
1113 rv.d = (*handler.b) (fs, ft);
1114 goto copcsr;
1115 }
1116 dcopuop:{
1117 ieee754dp fs;
1118
1119 DPFROMREG(fs, MIPSInst_FS(ir));
1120 rv.d = (*handler.u) (fs);
1121 goto copcsr;
1122 }
1123
1124 /* unary conv ops */
1125 case fcvts_op:{
1126 ieee754dp fs;
1127
1128 DPFROMREG(fs, MIPSInst_FS(ir));
1129 rv.s = ieee754sp_fdp(fs);
1130 rfmt = s_fmt;
1131 goto copcsr;
1132 }
1133 case fcvtd_op:
1134 return SIGILL; /* not defined */
1135
1136 case fcvtw_op:{
1137 ieee754dp fs;
1138
1139 DPFROMREG(fs, MIPSInst_FS(ir));
1140 rv.w = ieee754dp_tint(fs); /* wrong */
1141 rfmt = w_fmt;
1142 goto copcsr;
1143 }
1144
1145#if __mips >= 2 || defined(__mips64)
1146 case fround_op:
1147 case ftrunc_op:
1148 case fceil_op:
1149 case ffloor_op:{
1150 unsigned int oldrm = ieee754_csr.rm;
1151 ieee754dp fs;
1152
1153 DPFROMREG(fs, MIPSInst_FS(ir));
1154 ieee754_csr.rm = ieee_rm[modeindex(MIPSInst_FUNC(ir))];
1155 rv.w = ieee754dp_tint(fs);
1156 ieee754_csr.rm = oldrm;
1157 rfmt = w_fmt;
1158 goto copcsr;
1159 }
1160#endif
1161
1162#if defined(__mips64)
1163 case fcvtl_op:{
1164 ieee754dp fs;
1165
1166 DPFROMREG(fs, MIPSInst_FS(ir));
1167 rv.l = ieee754dp_tlong(fs);
1168 rfmt = l_fmt;
1169 goto copcsr;
1170 }
1171
1172 case froundl_op:
1173 case ftruncl_op:
1174 case fceill_op:
1175 case ffloorl_op:{
1176 unsigned int oldrm = ieee754_csr.rm;
1177 ieee754dp fs;
1178
1179 DPFROMREG(fs, MIPSInst_FS(ir));
1180 ieee754_csr.rm = ieee_rm[modeindex(MIPSInst_FUNC(ir))];
1181 rv.l = ieee754dp_tlong(fs);
1182 ieee754_csr.rm = oldrm;
1183 rfmt = l_fmt;
1184 goto copcsr;
1185 }
1186#endif /* __mips >= 3 */
1187
1188 default:
1189 if (MIPSInst_FUNC(ir) >= fcmp_op) {
1190 unsigned cmpop = MIPSInst_FUNC(ir) - fcmp_op;
1191 ieee754dp fs, ft;
1192
1193 DPFROMREG(fs, MIPSInst_FS(ir));
1194 DPFROMREG(ft, MIPSInst_FT(ir));
1195 rv.w = ieee754dp_cmp(fs, ft,
1196 cmptab[cmpop & 0x7], cmpop & 0x8);
1197 rfmt = -1;
1198 if ((cmpop & 0x8)
1199 &&
1200 ieee754_cxtest
1201 (IEEE754_INVALID_OPERATION))
1202 rcsr = FPU_CSR_INV_X | FPU_CSR_INV_S;
1203 else
1204 goto copcsr;
1205
1206 }
1207 else {
1208 return SIGILL;
1209 }
1210 break;
1211 }
1212 break;
1213 }
1214
1215 case w_fmt:{
1216 ieee754sp fs;
1217
1218 switch (MIPSInst_FUNC(ir)) {
1219 case fcvts_op:
1220 /* convert word to single precision real */
1221 SPFROMREG(fs, MIPSInst_FS(ir));
1222 rv.s = ieee754sp_fint(fs.bits);
1223 rfmt = s_fmt;
1224 goto copcsr;
1225 case fcvtd_op:
1226 /* convert word to double precision real */
1227 SPFROMREG(fs, MIPSInst_FS(ir));
1228 rv.d = ieee754dp_fint(fs.bits);
1229 rfmt = d_fmt;
1230 goto copcsr;
1231 default:
1232 return SIGILL;
1233 }
1234 break;
1235 }
1236
1237#if defined(__mips64)
1238 case l_fmt:{
1239 switch (MIPSInst_FUNC(ir)) {
1240 case fcvts_op:
1241 /* convert long to single precision real */
1242 rv.s = ieee754sp_flong(ctx->fpr[MIPSInst_FS(ir)]);
1243 rfmt = s_fmt;
1244 goto copcsr;
1245 case fcvtd_op:
1246 /* convert long to double precision real */
1247 rv.d = ieee754dp_flong(ctx->fpr[MIPSInst_FS(ir)]);
1248 rfmt = d_fmt;
1249 goto copcsr;
1250 default:
1251 return SIGILL;
1252 }
1253 break;
1254 }
1255#endif
1256
1257 default:
1258 return SIGILL;
1259 }
1260
1261 /*
1262 * Update the fpu CSR register for this operation.
1263 * If an exception is required, generate a tidy SIGFPE exception,
1264 * without updating the result register.
1265 * Note: cause exception bits do not accumulate, they are rewritten
1266 * for each op; only the flag/sticky bits accumulate.
1267 */
1268 ctx->fcr31 = (ctx->fcr31 & ~FPU_CSR_ALL_X) | rcsr;
1269 if ((ctx->fcr31 >> 5) & ctx->fcr31 & FPU_CSR_ALL_E) {
1270 /*printk ("SIGFPE: fpu csr = %08x\n",ctx->fcr31); */
1271 return SIGFPE;
1272 }
1273
1274 /*
1275 * Now we can safely write the result back to the register file.
1276 */
1277 switch (rfmt) {
1278 case -1:{
1279#if __mips >= 4
1280 cond = fpucondbit[MIPSInst_FD(ir) >> 2];
1281#else
1282 cond = FPU_CSR_COND;
1283#endif
1284 if (rv.w)
1285 ctx->fcr31 |= cond;
1286 else
1287 ctx->fcr31 &= ~cond;
1288 break;
1289 }
1290 case d_fmt:
1291 DPTOREG(rv.d, MIPSInst_FD(ir));
1292 break;
1293 case s_fmt:
1294 SPTOREG(rv.s, MIPSInst_FD(ir));
1295 break;
1296 case w_fmt:
1297 SITOREG(rv.w, MIPSInst_FD(ir));
1298 break;
1299#if defined(__mips64)
1300 case l_fmt:
1301 DITOREG(rv.l, MIPSInst_FD(ir));
1302 break;
1303#endif
1304 default:
1305 return SIGILL;
1306 }
1307
1308 return 0;
1309}
1310
1311int fpu_emulator_cop1Handler(struct pt_regs *xcp, struct mips_fpu_struct *ctx,
1312 int has_fpu, void *__user *fault_addr)
1313{
1314 unsigned long oldepc, prevepc;
1315 mips_instruction insn;
1316 int sig = 0;
1317
1318 oldepc = xcp->cp0_epc;
1319 do {
1320 prevepc = xcp->cp0_epc;
1321
1322 if (!access_ok(VERIFY_READ, xcp->cp0_epc, sizeof(mips_instruction))) {
1323 MIPS_FPU_EMU_INC_STATS(errors);
1324 *fault_addr = (mips_instruction __user *)xcp->cp0_epc;
1325 return SIGBUS;
1326 }
1327 if (__get_user(insn, (mips_instruction __user *) xcp->cp0_epc)) {
1328 MIPS_FPU_EMU_INC_STATS(errors);
1329 *fault_addr = (mips_instruction __user *)xcp->cp0_epc;
1330 return SIGSEGV;
1331 }
1332 if (insn == 0)
1333 xcp->cp0_epc += 4; /* skip nops */
1334 else {
1335 /*
1336 * The 'ieee754_csr' is an alias of
1337 * ctx->fcr31. No need to copy ctx->fcr31 to
1338 * ieee754_csr. But ieee754_csr.rm is ieee
1339 * library modes. (not mips rounding mode)
1340 */
1341 /* convert to ieee library modes */
1342 ieee754_csr.rm = ieee_rm[ieee754_csr.rm];
1343 sig = cop1Emulate(xcp, ctx, fault_addr);
1344 /* revert to mips rounding mode */
1345 ieee754_csr.rm = mips_rm[ieee754_csr.rm];
1346 }
1347
1348 if (has_fpu)
1349 break;
1350 if (sig)
1351 break;
1352
1353 cond_resched();
1354 } while (xcp->cp0_epc > prevepc);
1355
1356 /* SIGILL indicates a non-fpu instruction */
1357 if (sig == SIGILL && xcp->cp0_epc != oldepc)
1358 /* but if epc has advanced, then ignore it */
1359 sig = 0;
1360
1361 return sig;
1362}
1363
1364#ifdef CONFIG_DEBUG_FS
1365
1366static int fpuemu_stat_get(void *data, u64 *val)
1367{
1368 int cpu;
1369 unsigned long sum = 0;
1370 for_each_online_cpu(cpu) {
1371 struct mips_fpu_emulator_stats *ps;
1372 local_t *pv;
1373 ps = &per_cpu(fpuemustats, cpu);
1374 pv = (void *)ps + (unsigned long)data;
1375 sum += local_read(pv);
1376 }
1377 *val = sum;
1378 return 0;
1379}
1380DEFINE_SIMPLE_ATTRIBUTE(fops_fpuemu_stat, fpuemu_stat_get, NULL, "%llu\n");
1381
1382extern struct dentry *mips_debugfs_dir;
1383static int __init debugfs_fpuemu(void)
1384{
1385 struct dentry *d, *dir;
1386
1387 if (!mips_debugfs_dir)
1388 return -ENODEV;
1389 dir = debugfs_create_dir("fpuemustats", mips_debugfs_dir);
1390 if (!dir)
1391 return -ENOMEM;
1392
1393#define FPU_STAT_CREATE(M) \
1394 do { \
1395 d = debugfs_create_file(#M , S_IRUGO, dir, \
1396 (void *)offsetof(struct mips_fpu_emulator_stats, M), \
1397 &fops_fpuemu_stat); \
1398 if (!d) \
1399 return -ENOMEM; \
1400 } while (0)
1401
1402 FPU_STAT_CREATE(emulated);
1403 FPU_STAT_CREATE(loads);
1404 FPU_STAT_CREATE(stores);
1405 FPU_STAT_CREATE(cp1ops);
1406 FPU_STAT_CREATE(cp1xops);
1407 FPU_STAT_CREATE(errors);
1408
1409 return 0;
1410}
1411__initcall(debugfs_fpuemu);
1412#endif