xref: /linux/arch/mips/math-emu/cp1emu.c (revision cf40a76e7d5874bb25f4404eecc58a2e033af885)
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 
57 static int fpu_emu(struct pt_regs *, struct mips_fpu_struct *,
58 	mips_instruction);
59 
60 static 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 */
72 const 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. */
84 static const int sd_format[] = {16, 17, 0, 0, 0, 0, 0, 0};
85 static const int sdps_format[] = {16, 17, 22, 0, 0, 0, 0, 0};
86 static const int dwl_format[] = {17, 20, 21, 0, 0, 0, 0, 0};
87 static 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  */
94 static 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  */
436 int 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 		case bltz_op:
479 			if ((long)regs->regs[insn.i_format.rs] < 0)
480 				*contpc = regs->cp0_epc +
481 					dec_insn.pc_inc +
482 					(insn.i_format.simmediate << 2);
483 			else
484 				*contpc = regs->cp0_epc +
485 					dec_insn.pc_inc +
486 					dec_insn.next_pc_inc;
487 			return 1;
488 		case bgezal_op:
489 		case bgezall_op:
490 			if (NO_R6EMU && (insn.i_format.rs ||
491 			    insn.i_format.rt == bgezall_op))
492 				break;
493 
494 			regs->regs[31] = regs->cp0_epc +
495 				dec_insn.pc_inc +
496 				dec_insn.next_pc_inc;
497 			/* Fall through */
498 		case bgezl_op:
499 			if (NO_R6EMU)
500 				break;
501 		case bgez_op:
502 			if ((long)regs->regs[insn.i_format.rs] >= 0)
503 				*contpc = regs->cp0_epc +
504 					dec_insn.pc_inc +
505 					(insn.i_format.simmediate << 2);
506 			else
507 				*contpc = regs->cp0_epc +
508 					dec_insn.pc_inc +
509 					dec_insn.next_pc_inc;
510 			return 1;
511 		}
512 		break;
513 	case jalx_op:
514 		set_isa16_mode(bit);
515 	case jal_op:
516 		regs->regs[31] = regs->cp0_epc +
517 			dec_insn.pc_inc +
518 			dec_insn.next_pc_inc;
519 		/* Fall through */
520 	case j_op:
521 		*contpc = regs->cp0_epc + dec_insn.pc_inc;
522 		*contpc >>= 28;
523 		*contpc <<= 28;
524 		*contpc |= (insn.j_format.target << 2);
525 		/* Set microMIPS mode bit: XOR for jalx. */
526 		*contpc ^= bit;
527 		return 1;
528 	case beql_op:
529 		if (NO_R6EMU)
530 			break;
531 	case beq_op:
532 		if (regs->regs[insn.i_format.rs] ==
533 		    regs->regs[insn.i_format.rt])
534 			*contpc = regs->cp0_epc +
535 				dec_insn.pc_inc +
536 				(insn.i_format.simmediate << 2);
537 		else
538 			*contpc = regs->cp0_epc +
539 				dec_insn.pc_inc +
540 				dec_insn.next_pc_inc;
541 		return 1;
542 	case bnel_op:
543 		if (NO_R6EMU)
544 			break;
545 	case bne_op:
546 		if (regs->regs[insn.i_format.rs] !=
547 		    regs->regs[insn.i_format.rt])
548 			*contpc = regs->cp0_epc +
549 				dec_insn.pc_inc +
550 				(insn.i_format.simmediate << 2);
551 		else
552 			*contpc = regs->cp0_epc +
553 				dec_insn.pc_inc +
554 				dec_insn.next_pc_inc;
555 		return 1;
556 	case blezl_op:
557 		if (!insn.i_format.rt && NO_R6EMU)
558 			break;
559 	case blez_op:
560 
561 		/*
562 		 * Compact branches for R6 for the
563 		 * blez and blezl opcodes.
564 		 * BLEZ  | rs = 0 | rt != 0  == BLEZALC
565 		 * BLEZ  | rs = rt != 0      == BGEZALC
566 		 * BLEZ  | rs != 0 | rt != 0 == BGEUC
567 		 * BLEZL | rs = 0 | rt != 0  == BLEZC
568 		 * BLEZL | rs = rt != 0      == BGEZC
569 		 * BLEZL | rs != 0 | rt != 0 == BGEC
570 		 *
571 		 * For real BLEZ{,L}, rt is always 0.
572 		 */
573 		if (cpu_has_mips_r6 && insn.i_format.rt) {
574 			if ((insn.i_format.opcode == blez_op) &&
575 			    ((!insn.i_format.rs && insn.i_format.rt) ||
576 			     (insn.i_format.rs == insn.i_format.rt)))
577 				regs->regs[31] = regs->cp0_epc +
578 					dec_insn.pc_inc;
579 			*contpc = regs->cp0_epc + dec_insn.pc_inc +
580 				dec_insn.next_pc_inc;
581 
582 			return 1;
583 		}
584 		if ((long)regs->regs[insn.i_format.rs] <= 0)
585 			*contpc = regs->cp0_epc +
586 				dec_insn.pc_inc +
587 				(insn.i_format.simmediate << 2);
588 		else
589 			*contpc = regs->cp0_epc +
590 				dec_insn.pc_inc +
591 				dec_insn.next_pc_inc;
592 		return 1;
593 	case bgtzl_op:
594 		if (!insn.i_format.rt && NO_R6EMU)
595 			break;
596 	case bgtz_op:
597 		/*
598 		 * Compact branches for R6 for the
599 		 * bgtz and bgtzl opcodes.
600 		 * BGTZ  | rs = 0 | rt != 0  == BGTZALC
601 		 * BGTZ  | rs = rt != 0      == BLTZALC
602 		 * BGTZ  | rs != 0 | rt != 0 == BLTUC
603 		 * BGTZL | rs = 0 | rt != 0  == BGTZC
604 		 * BGTZL | rs = rt != 0      == BLTZC
605 		 * BGTZL | rs != 0 | rt != 0 == BLTC
606 		 *
607 		 * *ZALC varint for BGTZ &&& rt != 0
608 		 * For real GTZ{,L}, rt is always 0.
609 		 */
610 		if (cpu_has_mips_r6 && insn.i_format.rt) {
611 			if ((insn.i_format.opcode == blez_op) &&
612 			    ((!insn.i_format.rs && insn.i_format.rt) ||
613 			     (insn.i_format.rs == insn.i_format.rt)))
614 				regs->regs[31] = regs->cp0_epc +
615 					dec_insn.pc_inc;
616 			*contpc = regs->cp0_epc + dec_insn.pc_inc +
617 				dec_insn.next_pc_inc;
618 
619 			return 1;
620 		}
621 
622 		if ((long)regs->regs[insn.i_format.rs] > 0)
623 			*contpc = regs->cp0_epc +
624 				dec_insn.pc_inc +
625 				(insn.i_format.simmediate << 2);
626 		else
627 			*contpc = regs->cp0_epc +
628 				dec_insn.pc_inc +
629 				dec_insn.next_pc_inc;
630 		return 1;
631 	case pop10_op:
632 	case pop30_op:
633 		if (!cpu_has_mips_r6)
634 			break;
635 		if (insn.i_format.rt && !insn.i_format.rs)
636 			regs->regs[31] = regs->cp0_epc + 4;
637 		*contpc = regs->cp0_epc + dec_insn.pc_inc +
638 			dec_insn.next_pc_inc;
639 
640 		return 1;
641 #ifdef CONFIG_CPU_CAVIUM_OCTEON
642 	case lwc2_op: /* This is bbit0 on Octeon */
643 		if ((regs->regs[insn.i_format.rs] & (1ull<<insn.i_format.rt)) == 0)
644 			*contpc = regs->cp0_epc + 4 + (insn.i_format.simmediate << 2);
645 		else
646 			*contpc = regs->cp0_epc + 8;
647 		return 1;
648 	case ldc2_op: /* This is bbit032 on Octeon */
649 		if ((regs->regs[insn.i_format.rs] & (1ull<<(insn.i_format.rt + 32))) == 0)
650 			*contpc = regs->cp0_epc + 4 + (insn.i_format.simmediate << 2);
651 		else
652 			*contpc = regs->cp0_epc + 8;
653 		return 1;
654 	case swc2_op: /* This is bbit1 on Octeon */
655 		if (regs->regs[insn.i_format.rs] & (1ull<<insn.i_format.rt))
656 			*contpc = regs->cp0_epc + 4 + (insn.i_format.simmediate << 2);
657 		else
658 			*contpc = regs->cp0_epc + 8;
659 		return 1;
660 	case sdc2_op: /* This is bbit132 on Octeon */
661 		if (regs->regs[insn.i_format.rs] & (1ull<<(insn.i_format.rt + 32)))
662 			*contpc = regs->cp0_epc + 4 + (insn.i_format.simmediate << 2);
663 		else
664 			*contpc = regs->cp0_epc + 8;
665 		return 1;
666 #else
667 	case bc6_op:
668 		/*
669 		 * Only valid for MIPS R6 but we can still end up
670 		 * here from a broken userland so just tell emulator
671 		 * this is not a branch and let it break later on.
672 		 */
673 		if  (!cpu_has_mips_r6)
674 			break;
675 		*contpc = regs->cp0_epc + dec_insn.pc_inc +
676 			dec_insn.next_pc_inc;
677 
678 		return 1;
679 	case balc6_op:
680 		if (!cpu_has_mips_r6)
681 			break;
682 		regs->regs[31] = regs->cp0_epc + 4;
683 		*contpc = regs->cp0_epc + dec_insn.pc_inc +
684 			dec_insn.next_pc_inc;
685 
686 		return 1;
687 	case pop66_op:
688 		if (!cpu_has_mips_r6)
689 			break;
690 		*contpc = regs->cp0_epc + dec_insn.pc_inc +
691 			dec_insn.next_pc_inc;
692 
693 		return 1;
694 	case pop76_op:
695 		if (!cpu_has_mips_r6)
696 			break;
697 		if (!insn.i_format.rs)
698 			regs->regs[31] = regs->cp0_epc + 4;
699 		*contpc = regs->cp0_epc + dec_insn.pc_inc +
700 			dec_insn.next_pc_inc;
701 
702 		return 1;
703 #endif
704 	case cop0_op:
705 	case cop1_op:
706 		/* Need to check for R6 bc1nez and bc1eqz branches */
707 		if (cpu_has_mips_r6 &&
708 		    ((insn.i_format.rs == bc1eqz_op) ||
709 		     (insn.i_format.rs == bc1nez_op))) {
710 			bit = 0;
711 			fpr = &current->thread.fpu.fpr[insn.i_format.rt];
712 			bit0 = get_fpr32(fpr, 0) & 0x1;
713 			switch (insn.i_format.rs) {
714 			case bc1eqz_op:
715 				bit = bit0 == 0;
716 				break;
717 			case bc1nez_op:
718 				bit = bit0 != 0;
719 				break;
720 			}
721 			if (bit)
722 				*contpc = regs->cp0_epc +
723 					dec_insn.pc_inc +
724 					(insn.i_format.simmediate << 2);
725 			else
726 				*contpc = regs->cp0_epc +
727 					dec_insn.pc_inc +
728 					dec_insn.next_pc_inc;
729 
730 			return 1;
731 		}
732 		/* R2/R6 compatible cop1 instruction. Fall through */
733 	case cop2_op:
734 	case cop1x_op:
735 		if (insn.i_format.rs == bc_op) {
736 			preempt_disable();
737 			if (is_fpu_owner())
738 			        fcr31 = read_32bit_cp1_register(CP1_STATUS);
739 			else
740 				fcr31 = current->thread.fpu.fcr31;
741 			preempt_enable();
742 
743 			bit = (insn.i_format.rt >> 2);
744 			bit += (bit != 0);
745 			bit += 23;
746 			switch (insn.i_format.rt & 3) {
747 			case 0:	/* bc1f */
748 			case 2:	/* bc1fl */
749 				if (~fcr31 & (1 << bit))
750 					*contpc = regs->cp0_epc +
751 						dec_insn.pc_inc +
752 						(insn.i_format.simmediate << 2);
753 				else
754 					*contpc = regs->cp0_epc +
755 						dec_insn.pc_inc +
756 						dec_insn.next_pc_inc;
757 				return 1;
758 			case 1:	/* bc1t */
759 			case 3:	/* bc1tl */
760 				if (fcr31 & (1 << bit))
761 					*contpc = regs->cp0_epc +
762 						dec_insn.pc_inc +
763 						(insn.i_format.simmediate << 2);
764 				else
765 					*contpc = regs->cp0_epc +
766 						dec_insn.pc_inc +
767 						dec_insn.next_pc_inc;
768 				return 1;
769 			}
770 		}
771 		break;
772 	}
773 	return 0;
774 }
775 
776 /*
777  * In the Linux kernel, we support selection of FPR format on the
778  * basis of the Status.FR bit.	If an FPU is not present, the FR bit
779  * is hardwired to zero, which would imply a 32-bit FPU even for
780  * 64-bit CPUs so we rather look at TIF_32BIT_FPREGS.
781  * FPU emu is slow and bulky and optimizing this function offers fairly
782  * sizeable benefits so we try to be clever and make this function return
783  * a constant whenever possible, that is on 64-bit kernels without O32
784  * compatibility enabled and on 32-bit without 64-bit FPU support.
785  */
786 static inline int cop1_64bit(struct pt_regs *xcp)
787 {
788 	if (IS_ENABLED(CONFIG_64BIT) && !IS_ENABLED(CONFIG_MIPS32_O32))
789 		return 1;
790 	else if (IS_ENABLED(CONFIG_32BIT) &&
791 		 !IS_ENABLED(CONFIG_MIPS_O32_FP64_SUPPORT))
792 		return 0;
793 
794 	return !test_thread_flag(TIF_32BIT_FPREGS);
795 }
796 
797 static inline bool hybrid_fprs(void)
798 {
799 	return test_thread_flag(TIF_HYBRID_FPREGS);
800 }
801 
802 #define SIFROMREG(si, x)						\
803 do {									\
804 	if (cop1_64bit(xcp) && !hybrid_fprs())				\
805 		(si) = (int)get_fpr32(&ctx->fpr[x], 0);			\
806 	else								\
807 		(si) = (int)get_fpr32(&ctx->fpr[(x) & ~1], (x) & 1);	\
808 } while (0)
809 
810 #define SITOREG(si, x)							\
811 do {									\
812 	if (cop1_64bit(xcp) && !hybrid_fprs()) {			\
813 		unsigned int i;						\
814 		set_fpr32(&ctx->fpr[x], 0, si);				\
815 		for (i = 1; i < ARRAY_SIZE(ctx->fpr[x].val32); i++)	\
816 			set_fpr32(&ctx->fpr[x], i, 0);			\
817 	} else {							\
818 		set_fpr32(&ctx->fpr[(x) & ~1], (x) & 1, si);		\
819 	}								\
820 } while (0)
821 
822 #define SIFROMHREG(si, x)	((si) = (int)get_fpr32(&ctx->fpr[x], 1))
823 
824 #define SITOHREG(si, x)							\
825 do {									\
826 	unsigned int i;							\
827 	set_fpr32(&ctx->fpr[x], 1, si);					\
828 	for (i = 2; i < ARRAY_SIZE(ctx->fpr[x].val32); i++)		\
829 		set_fpr32(&ctx->fpr[x], i, 0);				\
830 } while (0)
831 
832 #define DIFROMREG(di, x)						\
833 	((di) = get_fpr64(&ctx->fpr[(x) & ~(cop1_64bit(xcp) ^ 1)], 0))
834 
835 #define DITOREG(di, x)							\
836 do {									\
837 	unsigned int fpr, i;						\
838 	fpr = (x) & ~(cop1_64bit(xcp) ^ 1);				\
839 	set_fpr64(&ctx->fpr[fpr], 0, di);				\
840 	for (i = 1; i < ARRAY_SIZE(ctx->fpr[x].val64); i++)		\
841 		set_fpr64(&ctx->fpr[fpr], i, 0);			\
842 } while (0)
843 
844 #define SPFROMREG(sp, x) SIFROMREG((sp).bits, x)
845 #define SPTOREG(sp, x)	SITOREG((sp).bits, x)
846 #define DPFROMREG(dp, x)	DIFROMREG((dp).bits, x)
847 #define DPTOREG(dp, x)	DITOREG((dp).bits, x)
848 
849 /*
850  * Emulate a CFC1 instruction.
851  */
852 static inline void cop1_cfc(struct pt_regs *xcp, struct mips_fpu_struct *ctx,
853 			    mips_instruction ir)
854 {
855 	u32 fcr31 = ctx->fcr31;
856 	u32 value = 0;
857 
858 	switch (MIPSInst_RD(ir)) {
859 	case FPCREG_CSR:
860 		value = fcr31;
861 		pr_debug("%p gpr[%d]<-csr=%08x\n",
862 			 (void *)xcp->cp0_epc, MIPSInst_RT(ir), value);
863 		break;
864 
865 	case FPCREG_FENR:
866 		if (!cpu_has_mips_r)
867 			break;
868 		value = (fcr31 >> (FPU_CSR_FS_S - MIPS_FENR_FS_S)) &
869 			MIPS_FENR_FS;
870 		value |= fcr31 & (FPU_CSR_ALL_E | FPU_CSR_RM);
871 		pr_debug("%p gpr[%d]<-enr=%08x\n",
872 			 (void *)xcp->cp0_epc, MIPSInst_RT(ir), value);
873 		break;
874 
875 	case FPCREG_FEXR:
876 		if (!cpu_has_mips_r)
877 			break;
878 		value = fcr31 & (FPU_CSR_ALL_X | FPU_CSR_ALL_S);
879 		pr_debug("%p gpr[%d]<-exr=%08x\n",
880 			 (void *)xcp->cp0_epc, MIPSInst_RT(ir), value);
881 		break;
882 
883 	case FPCREG_FCCR:
884 		if (!cpu_has_mips_r)
885 			break;
886 		value = (fcr31 >> (FPU_CSR_COND_S - MIPS_FCCR_COND0_S)) &
887 			MIPS_FCCR_COND0;
888 		value |= (fcr31 >> (FPU_CSR_COND1_S - MIPS_FCCR_COND1_S)) &
889 			 (MIPS_FCCR_CONDX & ~MIPS_FCCR_COND0);
890 		pr_debug("%p gpr[%d]<-ccr=%08x\n",
891 			 (void *)xcp->cp0_epc, MIPSInst_RT(ir), value);
892 		break;
893 
894 	case FPCREG_RID:
895 		value = boot_cpu_data.fpu_id;
896 		break;
897 
898 	default:
899 		break;
900 	}
901 
902 	if (MIPSInst_RT(ir))
903 		xcp->regs[MIPSInst_RT(ir)] = value;
904 }
905 
906 /*
907  * Emulate a CTC1 instruction.
908  */
909 static inline void cop1_ctc(struct pt_regs *xcp, struct mips_fpu_struct *ctx,
910 			    mips_instruction ir)
911 {
912 	u32 fcr31 = ctx->fcr31;
913 	u32 value;
914 	u32 mask;
915 
916 	if (MIPSInst_RT(ir) == 0)
917 		value = 0;
918 	else
919 		value = xcp->regs[MIPSInst_RT(ir)];
920 
921 	switch (MIPSInst_RD(ir)) {
922 	case FPCREG_CSR:
923 		pr_debug("%p gpr[%d]->csr=%08x\n",
924 			 (void *)xcp->cp0_epc, MIPSInst_RT(ir), value);
925 
926 		/* Preserve read-only bits.  */
927 		mask = boot_cpu_data.fpu_msk31;
928 		fcr31 = (value & ~mask) | (fcr31 & mask);
929 		break;
930 
931 	case FPCREG_FENR:
932 		if (!cpu_has_mips_r)
933 			break;
934 		pr_debug("%p gpr[%d]->enr=%08x\n",
935 			 (void *)xcp->cp0_epc, MIPSInst_RT(ir), value);
936 		fcr31 &= ~(FPU_CSR_FS | FPU_CSR_ALL_E | FPU_CSR_RM);
937 		fcr31 |= (value << (FPU_CSR_FS_S - MIPS_FENR_FS_S)) &
938 			 FPU_CSR_FS;
939 		fcr31 |= value & (FPU_CSR_ALL_E | FPU_CSR_RM);
940 		break;
941 
942 	case FPCREG_FEXR:
943 		if (!cpu_has_mips_r)
944 			break;
945 		pr_debug("%p gpr[%d]->exr=%08x\n",
946 			 (void *)xcp->cp0_epc, MIPSInst_RT(ir), value);
947 		fcr31 &= ~(FPU_CSR_ALL_X | FPU_CSR_ALL_S);
948 		fcr31 |= value & (FPU_CSR_ALL_X | FPU_CSR_ALL_S);
949 		break;
950 
951 	case FPCREG_FCCR:
952 		if (!cpu_has_mips_r)
953 			break;
954 		pr_debug("%p gpr[%d]->ccr=%08x\n",
955 			 (void *)xcp->cp0_epc, MIPSInst_RT(ir), value);
956 		fcr31 &= ~(FPU_CSR_CONDX | FPU_CSR_COND);
957 		fcr31 |= (value << (FPU_CSR_COND_S - MIPS_FCCR_COND0_S)) &
958 			 FPU_CSR_COND;
959 		fcr31 |= (value << (FPU_CSR_COND1_S - MIPS_FCCR_COND1_S)) &
960 			 FPU_CSR_CONDX;
961 		break;
962 
963 	default:
964 		break;
965 	}
966 
967 	ctx->fcr31 = fcr31;
968 }
969 
970 /*
971  * Emulate the single floating point instruction pointed at by EPC.
972  * Two instructions if the instruction is in a branch delay slot.
973  */
974 
975 static int cop1Emulate(struct pt_regs *xcp, struct mips_fpu_struct *ctx,
976 		struct mm_decoded_insn dec_insn, void __user **fault_addr)
977 {
978 	unsigned long contpc = xcp->cp0_epc + dec_insn.pc_inc;
979 	unsigned int cond, cbit, bit0;
980 	mips_instruction ir;
981 	int likely, pc_inc;
982 	union fpureg *fpr;
983 	u32 __user *wva;
984 	u64 __user *dva;
985 	u32 wval;
986 	u64 dval;
987 	int sig;
988 
989 	/*
990 	 * These are giving gcc a gentle hint about what to expect in
991 	 * dec_inst in order to do better optimization.
992 	 */
993 	if (!cpu_has_mmips && dec_insn.micro_mips_mode)
994 		unreachable();
995 
996 	/* XXX NEC Vr54xx bug workaround */
997 	if (delay_slot(xcp)) {
998 		if (dec_insn.micro_mips_mode) {
999 			if (!mm_isBranchInstr(xcp, dec_insn, &contpc))
1000 				clear_delay_slot(xcp);
1001 		} else {
1002 			if (!isBranchInstr(xcp, dec_insn, &contpc))
1003 				clear_delay_slot(xcp);
1004 		}
1005 	}
1006 
1007 	if (delay_slot(xcp)) {
1008 		/*
1009 		 * The instruction to be emulated is in a branch delay slot
1010 		 * which means that we have to	emulate the branch instruction
1011 		 * BEFORE we do the cop1 instruction.
1012 		 *
1013 		 * This branch could be a COP1 branch, but in that case we
1014 		 * would have had a trap for that instruction, and would not
1015 		 * come through this route.
1016 		 *
1017 		 * Linux MIPS branch emulator operates on context, updating the
1018 		 * cp0_epc.
1019 		 */
1020 		ir = dec_insn.next_insn;  /* process delay slot instr */
1021 		pc_inc = dec_insn.next_pc_inc;
1022 	} else {
1023 		ir = dec_insn.insn;       /* process current instr */
1024 		pc_inc = dec_insn.pc_inc;
1025 	}
1026 
1027 	/*
1028 	 * Since microMIPS FPU instructios are a subset of MIPS32 FPU
1029 	 * instructions, we want to convert microMIPS FPU instructions
1030 	 * into MIPS32 instructions so that we could reuse all of the
1031 	 * FPU emulation code.
1032 	 *
1033 	 * NOTE: We cannot do this for branch instructions since they
1034 	 *       are not a subset. Example: Cannot emulate a 16-bit
1035 	 *       aligned target address with a MIPS32 instruction.
1036 	 */
1037 	if (dec_insn.micro_mips_mode) {
1038 		/*
1039 		 * If next instruction is a 16-bit instruction, then it
1040 		 * it cannot be a FPU instruction. This could happen
1041 		 * since we can be called for non-FPU instructions.
1042 		 */
1043 		if ((pc_inc == 2) ||
1044 			(microMIPS32_to_MIPS32((union mips_instruction *)&ir)
1045 			 == SIGILL))
1046 			return SIGILL;
1047 	}
1048 
1049 emul:
1050 	perf_sw_event(PERF_COUNT_SW_EMULATION_FAULTS, 1, xcp, 0);
1051 	MIPS_FPU_EMU_INC_STATS(emulated);
1052 	switch (MIPSInst_OPCODE(ir)) {
1053 	case ldc1_op:
1054 		dva = (u64 __user *) (xcp->regs[MIPSInst_RS(ir)] +
1055 				     MIPSInst_SIMM(ir));
1056 		MIPS_FPU_EMU_INC_STATS(loads);
1057 
1058 		if (!access_ok(VERIFY_READ, dva, sizeof(u64))) {
1059 			MIPS_FPU_EMU_INC_STATS(errors);
1060 			*fault_addr = dva;
1061 			return SIGBUS;
1062 		}
1063 		if (__get_user(dval, dva)) {
1064 			MIPS_FPU_EMU_INC_STATS(errors);
1065 			*fault_addr = dva;
1066 			return SIGSEGV;
1067 		}
1068 		DITOREG(dval, MIPSInst_RT(ir));
1069 		break;
1070 
1071 	case sdc1_op:
1072 		dva = (u64 __user *) (xcp->regs[MIPSInst_RS(ir)] +
1073 				      MIPSInst_SIMM(ir));
1074 		MIPS_FPU_EMU_INC_STATS(stores);
1075 		DIFROMREG(dval, MIPSInst_RT(ir));
1076 		if (!access_ok(VERIFY_WRITE, dva, sizeof(u64))) {
1077 			MIPS_FPU_EMU_INC_STATS(errors);
1078 			*fault_addr = dva;
1079 			return SIGBUS;
1080 		}
1081 		if (__put_user(dval, dva)) {
1082 			MIPS_FPU_EMU_INC_STATS(errors);
1083 			*fault_addr = dva;
1084 			return SIGSEGV;
1085 		}
1086 		break;
1087 
1088 	case lwc1_op:
1089 		wva = (u32 __user *) (xcp->regs[MIPSInst_RS(ir)] +
1090 				      MIPSInst_SIMM(ir));
1091 		MIPS_FPU_EMU_INC_STATS(loads);
1092 		if (!access_ok(VERIFY_READ, wva, sizeof(u32))) {
1093 			MIPS_FPU_EMU_INC_STATS(errors);
1094 			*fault_addr = wva;
1095 			return SIGBUS;
1096 		}
1097 		if (__get_user(wval, wva)) {
1098 			MIPS_FPU_EMU_INC_STATS(errors);
1099 			*fault_addr = wva;
1100 			return SIGSEGV;
1101 		}
1102 		SITOREG(wval, MIPSInst_RT(ir));
1103 		break;
1104 
1105 	case swc1_op:
1106 		wva = (u32 __user *) (xcp->regs[MIPSInst_RS(ir)] +
1107 				      MIPSInst_SIMM(ir));
1108 		MIPS_FPU_EMU_INC_STATS(stores);
1109 		SIFROMREG(wval, MIPSInst_RT(ir));
1110 		if (!access_ok(VERIFY_WRITE, wva, sizeof(u32))) {
1111 			MIPS_FPU_EMU_INC_STATS(errors);
1112 			*fault_addr = wva;
1113 			return SIGBUS;
1114 		}
1115 		if (__put_user(wval, wva)) {
1116 			MIPS_FPU_EMU_INC_STATS(errors);
1117 			*fault_addr = wva;
1118 			return SIGSEGV;
1119 		}
1120 		break;
1121 
1122 	case cop1_op:
1123 		switch (MIPSInst_RS(ir)) {
1124 		case dmfc_op:
1125 			if (!cpu_has_mips_3_4_5 && !cpu_has_mips64)
1126 				return SIGILL;
1127 
1128 			/* copregister fs -> gpr[rt] */
1129 			if (MIPSInst_RT(ir) != 0) {
1130 				DIFROMREG(xcp->regs[MIPSInst_RT(ir)],
1131 					MIPSInst_RD(ir));
1132 			}
1133 			break;
1134 
1135 		case dmtc_op:
1136 			if (!cpu_has_mips_3_4_5 && !cpu_has_mips64)
1137 				return SIGILL;
1138 
1139 			/* copregister fs <- rt */
1140 			DITOREG(xcp->regs[MIPSInst_RT(ir)], MIPSInst_RD(ir));
1141 			break;
1142 
1143 		case mfhc_op:
1144 			if (!cpu_has_mips_r2_r6)
1145 				return SIGILL;
1146 
1147 			/* copregister rd -> gpr[rt] */
1148 			if (MIPSInst_RT(ir) != 0) {
1149 				SIFROMHREG(xcp->regs[MIPSInst_RT(ir)],
1150 					MIPSInst_RD(ir));
1151 			}
1152 			break;
1153 
1154 		case mthc_op:
1155 			if (!cpu_has_mips_r2_r6)
1156 				return SIGILL;
1157 
1158 			/* copregister rd <- gpr[rt] */
1159 			SITOHREG(xcp->regs[MIPSInst_RT(ir)], MIPSInst_RD(ir));
1160 			break;
1161 
1162 		case mfc_op:
1163 			/* copregister rd -> gpr[rt] */
1164 			if (MIPSInst_RT(ir) != 0) {
1165 				SIFROMREG(xcp->regs[MIPSInst_RT(ir)],
1166 					MIPSInst_RD(ir));
1167 			}
1168 			break;
1169 
1170 		case mtc_op:
1171 			/* copregister rd <- rt */
1172 			SITOREG(xcp->regs[MIPSInst_RT(ir)], MIPSInst_RD(ir));
1173 			break;
1174 
1175 		case cfc_op:
1176 			/* cop control register rd -> gpr[rt] */
1177 			cop1_cfc(xcp, ctx, ir);
1178 			break;
1179 
1180 		case ctc_op:
1181 			/* copregister rd <- rt */
1182 			cop1_ctc(xcp, ctx, ir);
1183 			if ((ctx->fcr31 >> 5) & ctx->fcr31 & FPU_CSR_ALL_E) {
1184 				return SIGFPE;
1185 			}
1186 			break;
1187 
1188 		case bc1eqz_op:
1189 		case bc1nez_op:
1190 			if (!cpu_has_mips_r6 || delay_slot(xcp))
1191 				return SIGILL;
1192 
1193 			cond = likely = 0;
1194 			fpr = &current->thread.fpu.fpr[MIPSInst_RT(ir)];
1195 			bit0 = get_fpr32(fpr, 0) & 0x1;
1196 			switch (MIPSInst_RS(ir)) {
1197 			case bc1eqz_op:
1198 				MIPS_FPU_EMU_INC_STATS(bc1eqz);
1199 				cond = bit0 == 0;
1200 				break;
1201 			case bc1nez_op:
1202 				MIPS_FPU_EMU_INC_STATS(bc1nez);
1203 				cond = bit0 != 0;
1204 				break;
1205 			}
1206 			goto branch_common;
1207 
1208 		case bc_op:
1209 			if (delay_slot(xcp))
1210 				return SIGILL;
1211 
1212 			if (cpu_has_mips_4_5_r)
1213 				cbit = fpucondbit[MIPSInst_RT(ir) >> 2];
1214 			else
1215 				cbit = FPU_CSR_COND;
1216 			cond = ctx->fcr31 & cbit;
1217 
1218 			likely = 0;
1219 			switch (MIPSInst_RT(ir) & 3) {
1220 			case bcfl_op:
1221 				if (cpu_has_mips_2_3_4_5_r)
1222 					likely = 1;
1223 				/* Fall through */
1224 			case bcf_op:
1225 				cond = !cond;
1226 				break;
1227 			case bctl_op:
1228 				if (cpu_has_mips_2_3_4_5_r)
1229 					likely = 1;
1230 				/* Fall through */
1231 			case bct_op:
1232 				break;
1233 			}
1234 branch_common:
1235 			MIPS_FPU_EMU_INC_STATS(branches);
1236 			set_delay_slot(xcp);
1237 			if (cond) {
1238 				/*
1239 				 * Branch taken: emulate dslot instruction
1240 				 */
1241 				unsigned long bcpc;
1242 
1243 				/*
1244 				 * Remember EPC at the branch to point back
1245 				 * at so that any delay-slot instruction
1246 				 * signal is not silently ignored.
1247 				 */
1248 				bcpc = xcp->cp0_epc;
1249 				xcp->cp0_epc += dec_insn.pc_inc;
1250 
1251 				contpc = MIPSInst_SIMM(ir);
1252 				ir = dec_insn.next_insn;
1253 				if (dec_insn.micro_mips_mode) {
1254 					contpc = (xcp->cp0_epc + (contpc << 1));
1255 
1256 					/* If 16-bit instruction, not FPU. */
1257 					if ((dec_insn.next_pc_inc == 2) ||
1258 						(microMIPS32_to_MIPS32((union mips_instruction *)&ir) == SIGILL)) {
1259 
1260 						/*
1261 						 * Since this instruction will
1262 						 * be put on the stack with
1263 						 * 32-bit words, get around
1264 						 * this problem by putting a
1265 						 * NOP16 as the second one.
1266 						 */
1267 						if (dec_insn.next_pc_inc == 2)
1268 							ir = (ir & (~0xffff)) | MM_NOP16;
1269 
1270 						/*
1271 						 * Single step the non-CP1
1272 						 * instruction in the dslot.
1273 						 */
1274 						sig = mips_dsemul(xcp, ir,
1275 								  bcpc, contpc);
1276 						if (sig < 0)
1277 							break;
1278 						if (sig)
1279 							xcp->cp0_epc = bcpc;
1280 						/*
1281 						 * SIGILL forces out of
1282 						 * the emulation loop.
1283 						 */
1284 						return sig ? sig : SIGILL;
1285 					}
1286 				} else
1287 					contpc = (xcp->cp0_epc + (contpc << 2));
1288 
1289 				switch (MIPSInst_OPCODE(ir)) {
1290 				case lwc1_op:
1291 				case swc1_op:
1292 					goto emul;
1293 
1294 				case ldc1_op:
1295 				case sdc1_op:
1296 					if (cpu_has_mips_2_3_4_5_r)
1297 						goto emul;
1298 
1299 					goto bc_sigill;
1300 
1301 				case cop1_op:
1302 					goto emul;
1303 
1304 				case cop1x_op:
1305 					if (cpu_has_mips_4_5_64_r2_r6)
1306 						/* its one of ours */
1307 						goto emul;
1308 
1309 					goto bc_sigill;
1310 
1311 				case spec_op:
1312 					switch (MIPSInst_FUNC(ir)) {
1313 					case movc_op:
1314 						if (cpu_has_mips_4_5_r)
1315 							goto emul;
1316 
1317 						goto bc_sigill;
1318 					}
1319 					break;
1320 
1321 				bc_sigill:
1322 					xcp->cp0_epc = bcpc;
1323 					return SIGILL;
1324 				}
1325 
1326 				/*
1327 				 * Single step the non-cp1
1328 				 * instruction in the dslot
1329 				 */
1330 				sig = mips_dsemul(xcp, ir, bcpc, contpc);
1331 				if (sig < 0)
1332 					break;
1333 				if (sig)
1334 					xcp->cp0_epc = bcpc;
1335 				/* SIGILL forces out of the emulation loop.  */
1336 				return sig ? sig : SIGILL;
1337 			} else if (likely) {	/* branch not taken */
1338 				/*
1339 				 * branch likely nullifies
1340 				 * dslot if not taken
1341 				 */
1342 				xcp->cp0_epc += dec_insn.pc_inc;
1343 				contpc += dec_insn.pc_inc;
1344 				/*
1345 				 * else continue & execute
1346 				 * dslot as normal insn
1347 				 */
1348 			}
1349 			break;
1350 
1351 		default:
1352 			if (!(MIPSInst_RS(ir) & 0x10))
1353 				return SIGILL;
1354 
1355 			/* a real fpu computation instruction */
1356 			if ((sig = fpu_emu(xcp, ctx, ir)))
1357 				return sig;
1358 		}
1359 		break;
1360 
1361 	case cop1x_op:
1362 		if (!cpu_has_mips_4_5_64_r2_r6)
1363 			return SIGILL;
1364 
1365 		sig = fpux_emu(xcp, ctx, ir, fault_addr);
1366 		if (sig)
1367 			return sig;
1368 		break;
1369 
1370 	case spec_op:
1371 		if (!cpu_has_mips_4_5_r)
1372 			return SIGILL;
1373 
1374 		if (MIPSInst_FUNC(ir) != movc_op)
1375 			return SIGILL;
1376 		cond = fpucondbit[MIPSInst_RT(ir) >> 2];
1377 		if (((ctx->fcr31 & cond) != 0) == ((MIPSInst_RT(ir) & 1) != 0))
1378 			xcp->regs[MIPSInst_RD(ir)] =
1379 				xcp->regs[MIPSInst_RS(ir)];
1380 		break;
1381 	default:
1382 		return SIGILL;
1383 	}
1384 
1385 	/* we did it !! */
1386 	xcp->cp0_epc = contpc;
1387 	clear_delay_slot(xcp);
1388 
1389 	return 0;
1390 }
1391 
1392 /*
1393  * Conversion table from MIPS compare ops 48-63
1394  * cond = ieee754dp_cmp(x,y,IEEE754_UN,sig);
1395  */
1396 static const unsigned char cmptab[8] = {
1397 	0,			/* cmp_0 (sig) cmp_sf */
1398 	IEEE754_CUN,		/* cmp_un (sig) cmp_ngle */
1399 	IEEE754_CEQ,		/* cmp_eq (sig) cmp_seq */
1400 	IEEE754_CEQ | IEEE754_CUN,	/* cmp_ueq (sig) cmp_ngl  */
1401 	IEEE754_CLT,		/* cmp_olt (sig) cmp_lt */
1402 	IEEE754_CLT | IEEE754_CUN,	/* cmp_ult (sig) cmp_nge */
1403 	IEEE754_CLT | IEEE754_CEQ,	/* cmp_ole (sig) cmp_le */
1404 	IEEE754_CLT | IEEE754_CEQ | IEEE754_CUN,	/* cmp_ule (sig) cmp_ngt */
1405 };
1406 
1407 static const unsigned char negative_cmptab[8] = {
1408 	0, /* Reserved */
1409 	IEEE754_CLT | IEEE754_CGT | IEEE754_CEQ,
1410 	IEEE754_CLT | IEEE754_CGT | IEEE754_CUN,
1411 	IEEE754_CLT | IEEE754_CGT,
1412 	/* Reserved */
1413 };
1414 
1415 
1416 /*
1417  * Additional MIPS4 instructions
1418  */
1419 
1420 #define DEF3OP(name, p, f1, f2, f3)					\
1421 static union ieee754##p fpemu_##p##_##name(union ieee754##p r,		\
1422 	union ieee754##p s, union ieee754##p t)				\
1423 {									\
1424 	struct _ieee754_csr ieee754_csr_save;				\
1425 	s = f1(s, t);							\
1426 	ieee754_csr_save = ieee754_csr;					\
1427 	s = f2(s, r);							\
1428 	ieee754_csr_save.cx |= ieee754_csr.cx;				\
1429 	ieee754_csr_save.sx |= ieee754_csr.sx;				\
1430 	s = f3(s);							\
1431 	ieee754_csr.cx |= ieee754_csr_save.cx;				\
1432 	ieee754_csr.sx |= ieee754_csr_save.sx;				\
1433 	return s;							\
1434 }
1435 
1436 static union ieee754dp fpemu_dp_recip(union ieee754dp d)
1437 {
1438 	return ieee754dp_div(ieee754dp_one(0), d);
1439 }
1440 
1441 static union ieee754dp fpemu_dp_rsqrt(union ieee754dp d)
1442 {
1443 	return ieee754dp_div(ieee754dp_one(0), ieee754dp_sqrt(d));
1444 }
1445 
1446 static union ieee754sp fpemu_sp_recip(union ieee754sp s)
1447 {
1448 	return ieee754sp_div(ieee754sp_one(0), s);
1449 }
1450 
1451 static union ieee754sp fpemu_sp_rsqrt(union ieee754sp s)
1452 {
1453 	return ieee754sp_div(ieee754sp_one(0), ieee754sp_sqrt(s));
1454 }
1455 
1456 DEF3OP(madd, sp, ieee754sp_mul, ieee754sp_add, );
1457 DEF3OP(msub, sp, ieee754sp_mul, ieee754sp_sub, );
1458 DEF3OP(nmadd, sp, ieee754sp_mul, ieee754sp_add, ieee754sp_neg);
1459 DEF3OP(nmsub, sp, ieee754sp_mul, ieee754sp_sub, ieee754sp_neg);
1460 DEF3OP(madd, dp, ieee754dp_mul, ieee754dp_add, );
1461 DEF3OP(msub, dp, ieee754dp_mul, ieee754dp_sub, );
1462 DEF3OP(nmadd, dp, ieee754dp_mul, ieee754dp_add, ieee754dp_neg);
1463 DEF3OP(nmsub, dp, ieee754dp_mul, ieee754dp_sub, ieee754dp_neg);
1464 
1465 static int fpux_emu(struct pt_regs *xcp, struct mips_fpu_struct *ctx,
1466 	mips_instruction ir, void __user **fault_addr)
1467 {
1468 	unsigned int rcsr = 0;	/* resulting csr */
1469 
1470 	MIPS_FPU_EMU_INC_STATS(cp1xops);
1471 
1472 	switch (MIPSInst_FMA_FFMT(ir)) {
1473 	case s_fmt:{		/* 0 */
1474 
1475 		union ieee754sp(*handler) (union ieee754sp, union ieee754sp, union ieee754sp);
1476 		union ieee754sp fd, fr, fs, ft;
1477 		u32 __user *va;
1478 		u32 val;
1479 
1480 		switch (MIPSInst_FUNC(ir)) {
1481 		case lwxc1_op:
1482 			va = (void __user *) (xcp->regs[MIPSInst_FR(ir)] +
1483 				xcp->regs[MIPSInst_FT(ir)]);
1484 
1485 			MIPS_FPU_EMU_INC_STATS(loads);
1486 			if (!access_ok(VERIFY_READ, va, sizeof(u32))) {
1487 				MIPS_FPU_EMU_INC_STATS(errors);
1488 				*fault_addr = va;
1489 				return SIGBUS;
1490 			}
1491 			if (__get_user(val, va)) {
1492 				MIPS_FPU_EMU_INC_STATS(errors);
1493 				*fault_addr = va;
1494 				return SIGSEGV;
1495 			}
1496 			SITOREG(val, MIPSInst_FD(ir));
1497 			break;
1498 
1499 		case swxc1_op:
1500 			va = (void __user *) (xcp->regs[MIPSInst_FR(ir)] +
1501 				xcp->regs[MIPSInst_FT(ir)]);
1502 
1503 			MIPS_FPU_EMU_INC_STATS(stores);
1504 
1505 			SIFROMREG(val, MIPSInst_FS(ir));
1506 			if (!access_ok(VERIFY_WRITE, va, sizeof(u32))) {
1507 				MIPS_FPU_EMU_INC_STATS(errors);
1508 				*fault_addr = va;
1509 				return SIGBUS;
1510 			}
1511 			if (put_user(val, va)) {
1512 				MIPS_FPU_EMU_INC_STATS(errors);
1513 				*fault_addr = va;
1514 				return SIGSEGV;
1515 			}
1516 			break;
1517 
1518 		case madd_s_op:
1519 			handler = fpemu_sp_madd;
1520 			goto scoptop;
1521 		case msub_s_op:
1522 			handler = fpemu_sp_msub;
1523 			goto scoptop;
1524 		case nmadd_s_op:
1525 			handler = fpemu_sp_nmadd;
1526 			goto scoptop;
1527 		case nmsub_s_op:
1528 			handler = fpemu_sp_nmsub;
1529 			goto scoptop;
1530 
1531 		      scoptop:
1532 			SPFROMREG(fr, MIPSInst_FR(ir));
1533 			SPFROMREG(fs, MIPSInst_FS(ir));
1534 			SPFROMREG(ft, MIPSInst_FT(ir));
1535 			fd = (*handler) (fr, fs, ft);
1536 			SPTOREG(fd, MIPSInst_FD(ir));
1537 
1538 		      copcsr:
1539 			if (ieee754_cxtest(IEEE754_INEXACT)) {
1540 				MIPS_FPU_EMU_INC_STATS(ieee754_inexact);
1541 				rcsr |= FPU_CSR_INE_X | FPU_CSR_INE_S;
1542 			}
1543 			if (ieee754_cxtest(IEEE754_UNDERFLOW)) {
1544 				MIPS_FPU_EMU_INC_STATS(ieee754_underflow);
1545 				rcsr |= FPU_CSR_UDF_X | FPU_CSR_UDF_S;
1546 			}
1547 			if (ieee754_cxtest(IEEE754_OVERFLOW)) {
1548 				MIPS_FPU_EMU_INC_STATS(ieee754_overflow);
1549 				rcsr |= FPU_CSR_OVF_X | FPU_CSR_OVF_S;
1550 			}
1551 			if (ieee754_cxtest(IEEE754_INVALID_OPERATION)) {
1552 				MIPS_FPU_EMU_INC_STATS(ieee754_invalidop);
1553 				rcsr |= FPU_CSR_INV_X | FPU_CSR_INV_S;
1554 			}
1555 
1556 			ctx->fcr31 = (ctx->fcr31 & ~FPU_CSR_ALL_X) | rcsr;
1557 			if ((ctx->fcr31 >> 5) & ctx->fcr31 & FPU_CSR_ALL_E) {
1558 				/*printk ("SIGFPE: FPU csr = %08x\n",
1559 				   ctx->fcr31); */
1560 				return SIGFPE;
1561 			}
1562 
1563 			break;
1564 
1565 		default:
1566 			return SIGILL;
1567 		}
1568 		break;
1569 	}
1570 
1571 	case d_fmt:{		/* 1 */
1572 		union ieee754dp(*handler) (union ieee754dp, union ieee754dp, union ieee754dp);
1573 		union ieee754dp fd, fr, fs, ft;
1574 		u64 __user *va;
1575 		u64 val;
1576 
1577 		switch (MIPSInst_FUNC(ir)) {
1578 		case ldxc1_op:
1579 			va = (void __user *) (xcp->regs[MIPSInst_FR(ir)] +
1580 				xcp->regs[MIPSInst_FT(ir)]);
1581 
1582 			MIPS_FPU_EMU_INC_STATS(loads);
1583 			if (!access_ok(VERIFY_READ, va, sizeof(u64))) {
1584 				MIPS_FPU_EMU_INC_STATS(errors);
1585 				*fault_addr = va;
1586 				return SIGBUS;
1587 			}
1588 			if (__get_user(val, va)) {
1589 				MIPS_FPU_EMU_INC_STATS(errors);
1590 				*fault_addr = va;
1591 				return SIGSEGV;
1592 			}
1593 			DITOREG(val, MIPSInst_FD(ir));
1594 			break;
1595 
1596 		case sdxc1_op:
1597 			va = (void __user *) (xcp->regs[MIPSInst_FR(ir)] +
1598 				xcp->regs[MIPSInst_FT(ir)]);
1599 
1600 			MIPS_FPU_EMU_INC_STATS(stores);
1601 			DIFROMREG(val, MIPSInst_FS(ir));
1602 			if (!access_ok(VERIFY_WRITE, va, sizeof(u64))) {
1603 				MIPS_FPU_EMU_INC_STATS(errors);
1604 				*fault_addr = va;
1605 				return SIGBUS;
1606 			}
1607 			if (__put_user(val, va)) {
1608 				MIPS_FPU_EMU_INC_STATS(errors);
1609 				*fault_addr = va;
1610 				return SIGSEGV;
1611 			}
1612 			break;
1613 
1614 		case madd_d_op:
1615 			handler = fpemu_dp_madd;
1616 			goto dcoptop;
1617 		case msub_d_op:
1618 			handler = fpemu_dp_msub;
1619 			goto dcoptop;
1620 		case nmadd_d_op:
1621 			handler = fpemu_dp_nmadd;
1622 			goto dcoptop;
1623 		case nmsub_d_op:
1624 			handler = fpemu_dp_nmsub;
1625 			goto dcoptop;
1626 
1627 		      dcoptop:
1628 			DPFROMREG(fr, MIPSInst_FR(ir));
1629 			DPFROMREG(fs, MIPSInst_FS(ir));
1630 			DPFROMREG(ft, MIPSInst_FT(ir));
1631 			fd = (*handler) (fr, fs, ft);
1632 			DPTOREG(fd, MIPSInst_FD(ir));
1633 			goto copcsr;
1634 
1635 		default:
1636 			return SIGILL;
1637 		}
1638 		break;
1639 	}
1640 
1641 	case 0x3:
1642 		if (MIPSInst_FUNC(ir) != pfetch_op)
1643 			return SIGILL;
1644 
1645 		/* ignore prefx operation */
1646 		break;
1647 
1648 	default:
1649 		return SIGILL;
1650 	}
1651 
1652 	return 0;
1653 }
1654 
1655 
1656 
1657 /*
1658  * Emulate a single COP1 arithmetic instruction.
1659  */
1660 static int fpu_emu(struct pt_regs *xcp, struct mips_fpu_struct *ctx,
1661 	mips_instruction ir)
1662 {
1663 	int rfmt;		/* resulting format */
1664 	unsigned int rcsr = 0;	/* resulting csr */
1665 	unsigned int oldrm;
1666 	unsigned int cbit;
1667 	unsigned int cond;
1668 	union {
1669 		union ieee754dp d;
1670 		union ieee754sp s;
1671 		int w;
1672 		s64 l;
1673 	} rv;			/* resulting value */
1674 	u64 bits;
1675 
1676 	MIPS_FPU_EMU_INC_STATS(cp1ops);
1677 	switch (rfmt = (MIPSInst_FFMT(ir) & 0xf)) {
1678 	case s_fmt: {		/* 0 */
1679 		union {
1680 			union ieee754sp(*b) (union ieee754sp, union ieee754sp);
1681 			union ieee754sp(*u) (union ieee754sp);
1682 		} handler;
1683 		union ieee754sp fd, fs, ft;
1684 
1685 		switch (MIPSInst_FUNC(ir)) {
1686 			/* binary ops */
1687 		case fadd_op:
1688 			MIPS_FPU_EMU_INC_STATS(add_s);
1689 			handler.b = ieee754sp_add;
1690 			goto scopbop;
1691 		case fsub_op:
1692 			MIPS_FPU_EMU_INC_STATS(sub_s);
1693 			handler.b = ieee754sp_sub;
1694 			goto scopbop;
1695 		case fmul_op:
1696 			MIPS_FPU_EMU_INC_STATS(mul_s);
1697 			handler.b = ieee754sp_mul;
1698 			goto scopbop;
1699 		case fdiv_op:
1700 			MIPS_FPU_EMU_INC_STATS(div_s);
1701 			handler.b = ieee754sp_div;
1702 			goto scopbop;
1703 
1704 			/* unary  ops */
1705 		case fsqrt_op:
1706 			if (!cpu_has_mips_2_3_4_5_r)
1707 				return SIGILL;
1708 
1709 			MIPS_FPU_EMU_INC_STATS(sqrt_s);
1710 			handler.u = ieee754sp_sqrt;
1711 			goto scopuop;
1712 
1713 		/*
1714 		 * Note that on some MIPS IV implementations such as the
1715 		 * R5000 and R8000 the FSQRT and FRECIP instructions do not
1716 		 * achieve full IEEE-754 accuracy - however this emulator does.
1717 		 */
1718 		case frsqrt_op:
1719 			if (!cpu_has_mips_4_5_64_r2_r6)
1720 				return SIGILL;
1721 
1722 			MIPS_FPU_EMU_INC_STATS(rsqrt_s);
1723 			handler.u = fpemu_sp_rsqrt;
1724 			goto scopuop;
1725 
1726 		case frecip_op:
1727 			if (!cpu_has_mips_4_5_64_r2_r6)
1728 				return SIGILL;
1729 
1730 			MIPS_FPU_EMU_INC_STATS(recip_s);
1731 			handler.u = fpemu_sp_recip;
1732 			goto scopuop;
1733 
1734 		case fmovc_op:
1735 			if (!cpu_has_mips_4_5_r)
1736 				return SIGILL;
1737 
1738 			cond = fpucondbit[MIPSInst_FT(ir) >> 2];
1739 			if (((ctx->fcr31 & cond) != 0) !=
1740 				((MIPSInst_FT(ir) & 1) != 0))
1741 				return 0;
1742 			SPFROMREG(rv.s, MIPSInst_FS(ir));
1743 			break;
1744 
1745 		case fmovz_op:
1746 			if (!cpu_has_mips_4_5_r)
1747 				return SIGILL;
1748 
1749 			if (xcp->regs[MIPSInst_FT(ir)] != 0)
1750 				return 0;
1751 			SPFROMREG(rv.s, MIPSInst_FS(ir));
1752 			break;
1753 
1754 		case fmovn_op:
1755 			if (!cpu_has_mips_4_5_r)
1756 				return SIGILL;
1757 
1758 			if (xcp->regs[MIPSInst_FT(ir)] == 0)
1759 				return 0;
1760 			SPFROMREG(rv.s, MIPSInst_FS(ir));
1761 			break;
1762 
1763 		case fseleqz_op:
1764 			if (!cpu_has_mips_r6)
1765 				return SIGILL;
1766 
1767 			MIPS_FPU_EMU_INC_STATS(seleqz_s);
1768 			SPFROMREG(rv.s, MIPSInst_FT(ir));
1769 			if (rv.w & 0x1)
1770 				rv.w = 0;
1771 			else
1772 				SPFROMREG(rv.s, MIPSInst_FS(ir));
1773 			break;
1774 
1775 		case fselnez_op:
1776 			if (!cpu_has_mips_r6)
1777 				return SIGILL;
1778 
1779 			MIPS_FPU_EMU_INC_STATS(selnez_s);
1780 			SPFROMREG(rv.s, MIPSInst_FT(ir));
1781 			if (rv.w & 0x1)
1782 				SPFROMREG(rv.s, MIPSInst_FS(ir));
1783 			else
1784 				rv.w = 0;
1785 			break;
1786 
1787 		case fmaddf_op: {
1788 			union ieee754sp ft, fs, fd;
1789 
1790 			if (!cpu_has_mips_r6)
1791 				return SIGILL;
1792 
1793 			MIPS_FPU_EMU_INC_STATS(maddf_s);
1794 			SPFROMREG(ft, MIPSInst_FT(ir));
1795 			SPFROMREG(fs, MIPSInst_FS(ir));
1796 			SPFROMREG(fd, MIPSInst_FD(ir));
1797 			rv.s = ieee754sp_maddf(fd, fs, ft);
1798 			goto copcsr;
1799 		}
1800 
1801 		case fmsubf_op: {
1802 			union ieee754sp ft, fs, fd;
1803 
1804 			if (!cpu_has_mips_r6)
1805 				return SIGILL;
1806 
1807 			MIPS_FPU_EMU_INC_STATS(msubf_s);
1808 			SPFROMREG(ft, MIPSInst_FT(ir));
1809 			SPFROMREG(fs, MIPSInst_FS(ir));
1810 			SPFROMREG(fd, MIPSInst_FD(ir));
1811 			rv.s = ieee754sp_msubf(fd, fs, ft);
1812 			goto copcsr;
1813 		}
1814 
1815 		case frint_op: {
1816 			union ieee754sp fs;
1817 
1818 			if (!cpu_has_mips_r6)
1819 				return SIGILL;
1820 
1821 			MIPS_FPU_EMU_INC_STATS(rint_s);
1822 			SPFROMREG(fs, MIPSInst_FS(ir));
1823 			rv.s = ieee754sp_rint(fs);
1824 			goto copcsr;
1825 		}
1826 
1827 		case fclass_op: {
1828 			union ieee754sp fs;
1829 
1830 			if (!cpu_has_mips_r6)
1831 				return SIGILL;
1832 
1833 			MIPS_FPU_EMU_INC_STATS(class_s);
1834 			SPFROMREG(fs, MIPSInst_FS(ir));
1835 			rv.w = ieee754sp_2008class(fs);
1836 			rfmt = w_fmt;
1837 			goto copcsr;
1838 		}
1839 
1840 		case fmin_op: {
1841 			union ieee754sp fs, ft;
1842 
1843 			if (!cpu_has_mips_r6)
1844 				return SIGILL;
1845 
1846 			MIPS_FPU_EMU_INC_STATS(min_s);
1847 			SPFROMREG(ft, MIPSInst_FT(ir));
1848 			SPFROMREG(fs, MIPSInst_FS(ir));
1849 			rv.s = ieee754sp_fmin(fs, ft);
1850 			goto copcsr;
1851 		}
1852 
1853 		case fmina_op: {
1854 			union ieee754sp fs, ft;
1855 
1856 			if (!cpu_has_mips_r6)
1857 				return SIGILL;
1858 
1859 			MIPS_FPU_EMU_INC_STATS(mina_s);
1860 			SPFROMREG(ft, MIPSInst_FT(ir));
1861 			SPFROMREG(fs, MIPSInst_FS(ir));
1862 			rv.s = ieee754sp_fmina(fs, ft);
1863 			goto copcsr;
1864 		}
1865 
1866 		case fmax_op: {
1867 			union ieee754sp fs, ft;
1868 
1869 			if (!cpu_has_mips_r6)
1870 				return SIGILL;
1871 
1872 			MIPS_FPU_EMU_INC_STATS(max_s);
1873 			SPFROMREG(ft, MIPSInst_FT(ir));
1874 			SPFROMREG(fs, MIPSInst_FS(ir));
1875 			rv.s = ieee754sp_fmax(fs, ft);
1876 			goto copcsr;
1877 		}
1878 
1879 		case fmaxa_op: {
1880 			union ieee754sp fs, ft;
1881 
1882 			if (!cpu_has_mips_r6)
1883 				return SIGILL;
1884 
1885 			MIPS_FPU_EMU_INC_STATS(maxa_s);
1886 			SPFROMREG(ft, MIPSInst_FT(ir));
1887 			SPFROMREG(fs, MIPSInst_FS(ir));
1888 			rv.s = ieee754sp_fmaxa(fs, ft);
1889 			goto copcsr;
1890 		}
1891 
1892 		case fabs_op:
1893 			MIPS_FPU_EMU_INC_STATS(abs_s);
1894 			handler.u = ieee754sp_abs;
1895 			goto scopuop;
1896 
1897 		case fneg_op:
1898 			MIPS_FPU_EMU_INC_STATS(neg_s);
1899 			handler.u = ieee754sp_neg;
1900 			goto scopuop;
1901 
1902 		case fmov_op:
1903 			/* an easy one */
1904 			MIPS_FPU_EMU_INC_STATS(mov_s);
1905 			SPFROMREG(rv.s, MIPSInst_FS(ir));
1906 			goto copcsr;
1907 
1908 			/* binary op on handler */
1909 scopbop:
1910 			SPFROMREG(fs, MIPSInst_FS(ir));
1911 			SPFROMREG(ft, MIPSInst_FT(ir));
1912 
1913 			rv.s = (*handler.b) (fs, ft);
1914 			goto copcsr;
1915 scopuop:
1916 			SPFROMREG(fs, MIPSInst_FS(ir));
1917 			rv.s = (*handler.u) (fs);
1918 			goto copcsr;
1919 copcsr:
1920 			if (ieee754_cxtest(IEEE754_INEXACT)) {
1921 				MIPS_FPU_EMU_INC_STATS(ieee754_inexact);
1922 				rcsr |= FPU_CSR_INE_X | FPU_CSR_INE_S;
1923 			}
1924 			if (ieee754_cxtest(IEEE754_UNDERFLOW)) {
1925 				MIPS_FPU_EMU_INC_STATS(ieee754_underflow);
1926 				rcsr |= FPU_CSR_UDF_X | FPU_CSR_UDF_S;
1927 			}
1928 			if (ieee754_cxtest(IEEE754_OVERFLOW)) {
1929 				MIPS_FPU_EMU_INC_STATS(ieee754_overflow);
1930 				rcsr |= FPU_CSR_OVF_X | FPU_CSR_OVF_S;
1931 			}
1932 			if (ieee754_cxtest(IEEE754_ZERO_DIVIDE)) {
1933 				MIPS_FPU_EMU_INC_STATS(ieee754_zerodiv);
1934 				rcsr |= FPU_CSR_DIV_X | FPU_CSR_DIV_S;
1935 			}
1936 			if (ieee754_cxtest(IEEE754_INVALID_OPERATION)) {
1937 				MIPS_FPU_EMU_INC_STATS(ieee754_invalidop);
1938 				rcsr |= FPU_CSR_INV_X | FPU_CSR_INV_S;
1939 			}
1940 			break;
1941 
1942 			/* unary conv ops */
1943 		case fcvts_op:
1944 			return SIGILL;	/* not defined */
1945 
1946 		case fcvtd_op:
1947 			MIPS_FPU_EMU_INC_STATS(cvt_d_s);
1948 			SPFROMREG(fs, MIPSInst_FS(ir));
1949 			rv.d = ieee754dp_fsp(fs);
1950 			rfmt = d_fmt;
1951 			goto copcsr;
1952 
1953 		case fcvtw_op:
1954 			MIPS_FPU_EMU_INC_STATS(cvt_w_s);
1955 			SPFROMREG(fs, MIPSInst_FS(ir));
1956 			rv.w = ieee754sp_tint(fs);
1957 			rfmt = w_fmt;
1958 			goto copcsr;
1959 
1960 		case fround_op:
1961 		case ftrunc_op:
1962 		case fceil_op:
1963 		case ffloor_op:
1964 			if (!cpu_has_mips_2_3_4_5_r)
1965 				return SIGILL;
1966 
1967 			if (MIPSInst_FUNC(ir) == fceil_op)
1968 				MIPS_FPU_EMU_INC_STATS(ceil_w_s);
1969 			if (MIPSInst_FUNC(ir) == ffloor_op)
1970 				MIPS_FPU_EMU_INC_STATS(floor_w_s);
1971 			if (MIPSInst_FUNC(ir) == fround_op)
1972 				MIPS_FPU_EMU_INC_STATS(round_w_s);
1973 			if (MIPSInst_FUNC(ir) == ftrunc_op)
1974 				MIPS_FPU_EMU_INC_STATS(trunc_w_s);
1975 
1976 			oldrm = ieee754_csr.rm;
1977 			SPFROMREG(fs, MIPSInst_FS(ir));
1978 			ieee754_csr.rm = MIPSInst_FUNC(ir);
1979 			rv.w = ieee754sp_tint(fs);
1980 			ieee754_csr.rm = oldrm;
1981 			rfmt = w_fmt;
1982 			goto copcsr;
1983 
1984 		case fsel_op:
1985 			if (!cpu_has_mips_r6)
1986 				return SIGILL;
1987 
1988 			MIPS_FPU_EMU_INC_STATS(sel_s);
1989 			SPFROMREG(fd, MIPSInst_FD(ir));
1990 			if (fd.bits & 0x1)
1991 				SPFROMREG(rv.s, MIPSInst_FT(ir));
1992 			else
1993 				SPFROMREG(rv.s, MIPSInst_FS(ir));
1994 			break;
1995 
1996 		case fcvtl_op:
1997 			if (!cpu_has_mips_3_4_5_64_r2_r6)
1998 				return SIGILL;
1999 
2000 			MIPS_FPU_EMU_INC_STATS(cvt_l_s);
2001 			SPFROMREG(fs, MIPSInst_FS(ir));
2002 			rv.l = ieee754sp_tlong(fs);
2003 			rfmt = l_fmt;
2004 			goto copcsr;
2005 
2006 		case froundl_op:
2007 		case ftruncl_op:
2008 		case fceill_op:
2009 		case ffloorl_op:
2010 			if (!cpu_has_mips_3_4_5_64_r2_r6)
2011 				return SIGILL;
2012 
2013 			if (MIPSInst_FUNC(ir) == fceill_op)
2014 				MIPS_FPU_EMU_INC_STATS(ceil_l_s);
2015 			if (MIPSInst_FUNC(ir) == ffloorl_op)
2016 				MIPS_FPU_EMU_INC_STATS(floor_l_s);
2017 			if (MIPSInst_FUNC(ir) == froundl_op)
2018 				MIPS_FPU_EMU_INC_STATS(round_l_s);
2019 			if (MIPSInst_FUNC(ir) == ftruncl_op)
2020 				MIPS_FPU_EMU_INC_STATS(trunc_l_s);
2021 
2022 			oldrm = ieee754_csr.rm;
2023 			SPFROMREG(fs, MIPSInst_FS(ir));
2024 			ieee754_csr.rm = MIPSInst_FUNC(ir);
2025 			rv.l = ieee754sp_tlong(fs);
2026 			ieee754_csr.rm = oldrm;
2027 			rfmt = l_fmt;
2028 			goto copcsr;
2029 
2030 		default:
2031 			if (!NO_R6EMU && MIPSInst_FUNC(ir) >= fcmp_op) {
2032 				unsigned int cmpop;
2033 				union ieee754sp fs, ft;
2034 
2035 				cmpop = MIPSInst_FUNC(ir) - fcmp_op;
2036 				SPFROMREG(fs, MIPSInst_FS(ir));
2037 				SPFROMREG(ft, MIPSInst_FT(ir));
2038 				rv.w = ieee754sp_cmp(fs, ft,
2039 					cmptab[cmpop & 0x7], cmpop & 0x8);
2040 				rfmt = -1;
2041 				if ((cmpop & 0x8) && ieee754_cxtest
2042 					(IEEE754_INVALID_OPERATION))
2043 					rcsr = FPU_CSR_INV_X | FPU_CSR_INV_S;
2044 				else
2045 					goto copcsr;
2046 
2047 			} else
2048 				return SIGILL;
2049 			break;
2050 		}
2051 		break;
2052 	}
2053 
2054 	case d_fmt: {
2055 		union ieee754dp fd, fs, ft;
2056 		union {
2057 			union ieee754dp(*b) (union ieee754dp, union ieee754dp);
2058 			union ieee754dp(*u) (union ieee754dp);
2059 		} handler;
2060 
2061 		switch (MIPSInst_FUNC(ir)) {
2062 			/* binary ops */
2063 		case fadd_op:
2064 			MIPS_FPU_EMU_INC_STATS(add_d);
2065 			handler.b = ieee754dp_add;
2066 			goto dcopbop;
2067 		case fsub_op:
2068 			MIPS_FPU_EMU_INC_STATS(sub_d);
2069 			handler.b = ieee754dp_sub;
2070 			goto dcopbop;
2071 		case fmul_op:
2072 			MIPS_FPU_EMU_INC_STATS(mul_d);
2073 			handler.b = ieee754dp_mul;
2074 			goto dcopbop;
2075 		case fdiv_op:
2076 			MIPS_FPU_EMU_INC_STATS(div_d);
2077 			handler.b = ieee754dp_div;
2078 			goto dcopbop;
2079 
2080 			/* unary  ops */
2081 		case fsqrt_op:
2082 			if (!cpu_has_mips_2_3_4_5_r)
2083 				return SIGILL;
2084 
2085 			MIPS_FPU_EMU_INC_STATS(sqrt_d);
2086 			handler.u = ieee754dp_sqrt;
2087 			goto dcopuop;
2088 		/*
2089 		 * Note that on some MIPS IV implementations such as the
2090 		 * R5000 and R8000 the FSQRT and FRECIP instructions do not
2091 		 * achieve full IEEE-754 accuracy - however this emulator does.
2092 		 */
2093 		case frsqrt_op:
2094 			if (!cpu_has_mips_4_5_64_r2_r6)
2095 				return SIGILL;
2096 
2097 			MIPS_FPU_EMU_INC_STATS(rsqrt_d);
2098 			handler.u = fpemu_dp_rsqrt;
2099 			goto dcopuop;
2100 		case frecip_op:
2101 			if (!cpu_has_mips_4_5_64_r2_r6)
2102 				return SIGILL;
2103 
2104 			MIPS_FPU_EMU_INC_STATS(recip_d);
2105 			handler.u = fpemu_dp_recip;
2106 			goto dcopuop;
2107 		case fmovc_op:
2108 			if (!cpu_has_mips_4_5_r)
2109 				return SIGILL;
2110 
2111 			cond = fpucondbit[MIPSInst_FT(ir) >> 2];
2112 			if (((ctx->fcr31 & cond) != 0) !=
2113 				((MIPSInst_FT(ir) & 1) != 0))
2114 				return 0;
2115 			DPFROMREG(rv.d, MIPSInst_FS(ir));
2116 			break;
2117 		case fmovz_op:
2118 			if (!cpu_has_mips_4_5_r)
2119 				return SIGILL;
2120 
2121 			if (xcp->regs[MIPSInst_FT(ir)] != 0)
2122 				return 0;
2123 			DPFROMREG(rv.d, MIPSInst_FS(ir));
2124 			break;
2125 		case fmovn_op:
2126 			if (!cpu_has_mips_4_5_r)
2127 				return SIGILL;
2128 
2129 			if (xcp->regs[MIPSInst_FT(ir)] == 0)
2130 				return 0;
2131 			DPFROMREG(rv.d, MIPSInst_FS(ir));
2132 			break;
2133 
2134 		case fseleqz_op:
2135 			if (!cpu_has_mips_r6)
2136 				return SIGILL;
2137 
2138 			MIPS_FPU_EMU_INC_STATS(seleqz_d);
2139 			DPFROMREG(rv.d, MIPSInst_FT(ir));
2140 			if (rv.l & 0x1)
2141 				rv.l = 0;
2142 			else
2143 				DPFROMREG(rv.d, MIPSInst_FS(ir));
2144 			break;
2145 
2146 		case fselnez_op:
2147 			if (!cpu_has_mips_r6)
2148 				return SIGILL;
2149 
2150 			MIPS_FPU_EMU_INC_STATS(selnez_d);
2151 			DPFROMREG(rv.d, MIPSInst_FT(ir));
2152 			if (rv.l & 0x1)
2153 				DPFROMREG(rv.d, MIPSInst_FS(ir));
2154 			else
2155 				rv.l = 0;
2156 			break;
2157 
2158 		case fmaddf_op: {
2159 			union ieee754dp ft, fs, fd;
2160 
2161 			if (!cpu_has_mips_r6)
2162 				return SIGILL;
2163 
2164 			MIPS_FPU_EMU_INC_STATS(maddf_d);
2165 			DPFROMREG(ft, MIPSInst_FT(ir));
2166 			DPFROMREG(fs, MIPSInst_FS(ir));
2167 			DPFROMREG(fd, MIPSInst_FD(ir));
2168 			rv.d = ieee754dp_maddf(fd, fs, ft);
2169 			goto copcsr;
2170 		}
2171 
2172 		case fmsubf_op: {
2173 			union ieee754dp ft, fs, fd;
2174 
2175 			if (!cpu_has_mips_r6)
2176 				return SIGILL;
2177 
2178 			MIPS_FPU_EMU_INC_STATS(msubf_d);
2179 			DPFROMREG(ft, MIPSInst_FT(ir));
2180 			DPFROMREG(fs, MIPSInst_FS(ir));
2181 			DPFROMREG(fd, MIPSInst_FD(ir));
2182 			rv.d = ieee754dp_msubf(fd, fs, ft);
2183 			goto copcsr;
2184 		}
2185 
2186 		case frint_op: {
2187 			union ieee754dp fs;
2188 
2189 			if (!cpu_has_mips_r6)
2190 				return SIGILL;
2191 
2192 			MIPS_FPU_EMU_INC_STATS(rint_d);
2193 			DPFROMREG(fs, MIPSInst_FS(ir));
2194 			rv.d = ieee754dp_rint(fs);
2195 			goto copcsr;
2196 		}
2197 
2198 		case fclass_op: {
2199 			union ieee754dp fs;
2200 
2201 			if (!cpu_has_mips_r6)
2202 				return SIGILL;
2203 
2204 			MIPS_FPU_EMU_INC_STATS(class_d);
2205 			DPFROMREG(fs, MIPSInst_FS(ir));
2206 			rv.l = ieee754dp_2008class(fs);
2207 			rfmt = l_fmt;
2208 			goto copcsr;
2209 		}
2210 
2211 		case fmin_op: {
2212 			union ieee754dp fs, ft;
2213 
2214 			if (!cpu_has_mips_r6)
2215 				return SIGILL;
2216 
2217 			MIPS_FPU_EMU_INC_STATS(min_d);
2218 			DPFROMREG(ft, MIPSInst_FT(ir));
2219 			DPFROMREG(fs, MIPSInst_FS(ir));
2220 			rv.d = ieee754dp_fmin(fs, ft);
2221 			goto copcsr;
2222 		}
2223 
2224 		case fmina_op: {
2225 			union ieee754dp fs, ft;
2226 
2227 			if (!cpu_has_mips_r6)
2228 				return SIGILL;
2229 
2230 			MIPS_FPU_EMU_INC_STATS(mina_d);
2231 			DPFROMREG(ft, MIPSInst_FT(ir));
2232 			DPFROMREG(fs, MIPSInst_FS(ir));
2233 			rv.d = ieee754dp_fmina(fs, ft);
2234 			goto copcsr;
2235 		}
2236 
2237 		case fmax_op: {
2238 			union ieee754dp fs, ft;
2239 
2240 			if (!cpu_has_mips_r6)
2241 				return SIGILL;
2242 
2243 			MIPS_FPU_EMU_INC_STATS(max_d);
2244 			DPFROMREG(ft, MIPSInst_FT(ir));
2245 			DPFROMREG(fs, MIPSInst_FS(ir));
2246 			rv.d = ieee754dp_fmax(fs, ft);
2247 			goto copcsr;
2248 		}
2249 
2250 		case fmaxa_op: {
2251 			union ieee754dp fs, ft;
2252 
2253 			if (!cpu_has_mips_r6)
2254 				return SIGILL;
2255 
2256 			MIPS_FPU_EMU_INC_STATS(maxa_d);
2257 			DPFROMREG(ft, MIPSInst_FT(ir));
2258 			DPFROMREG(fs, MIPSInst_FS(ir));
2259 			rv.d = ieee754dp_fmaxa(fs, ft);
2260 			goto copcsr;
2261 		}
2262 
2263 		case fabs_op:
2264 			MIPS_FPU_EMU_INC_STATS(abs_d);
2265 			handler.u = ieee754dp_abs;
2266 			goto dcopuop;
2267 
2268 		case fneg_op:
2269 			MIPS_FPU_EMU_INC_STATS(neg_d);
2270 			handler.u = ieee754dp_neg;
2271 			goto dcopuop;
2272 
2273 		case fmov_op:
2274 			/* an easy one */
2275 			MIPS_FPU_EMU_INC_STATS(mov_d);
2276 			DPFROMREG(rv.d, MIPSInst_FS(ir));
2277 			goto copcsr;
2278 
2279 			/* binary op on handler */
2280 dcopbop:
2281 			DPFROMREG(fs, MIPSInst_FS(ir));
2282 			DPFROMREG(ft, MIPSInst_FT(ir));
2283 
2284 			rv.d = (*handler.b) (fs, ft);
2285 			goto copcsr;
2286 dcopuop:
2287 			DPFROMREG(fs, MIPSInst_FS(ir));
2288 			rv.d = (*handler.u) (fs);
2289 			goto copcsr;
2290 
2291 		/*
2292 		 * unary conv ops
2293 		 */
2294 		case fcvts_op:
2295 			MIPS_FPU_EMU_INC_STATS(cvt_s_d);
2296 			DPFROMREG(fs, MIPSInst_FS(ir));
2297 			rv.s = ieee754sp_fdp(fs);
2298 			rfmt = s_fmt;
2299 			goto copcsr;
2300 
2301 		case fcvtd_op:
2302 			return SIGILL;	/* not defined */
2303 
2304 		case fcvtw_op:
2305 			MIPS_FPU_EMU_INC_STATS(cvt_w_d);
2306 			DPFROMREG(fs, MIPSInst_FS(ir));
2307 			rv.w = ieee754dp_tint(fs);	/* wrong */
2308 			rfmt = w_fmt;
2309 			goto copcsr;
2310 
2311 		case fround_op:
2312 		case ftrunc_op:
2313 		case fceil_op:
2314 		case ffloor_op:
2315 			if (!cpu_has_mips_2_3_4_5_r)
2316 				return SIGILL;
2317 
2318 			if (MIPSInst_FUNC(ir) == fceil_op)
2319 				MIPS_FPU_EMU_INC_STATS(ceil_w_d);
2320 			if (MIPSInst_FUNC(ir) == ffloor_op)
2321 				MIPS_FPU_EMU_INC_STATS(floor_w_d);
2322 			if (MIPSInst_FUNC(ir) == fround_op)
2323 				MIPS_FPU_EMU_INC_STATS(round_w_d);
2324 			if (MIPSInst_FUNC(ir) == ftrunc_op)
2325 				MIPS_FPU_EMU_INC_STATS(trunc_w_d);
2326 
2327 			oldrm = ieee754_csr.rm;
2328 			DPFROMREG(fs, MIPSInst_FS(ir));
2329 			ieee754_csr.rm = MIPSInst_FUNC(ir);
2330 			rv.w = ieee754dp_tint(fs);
2331 			ieee754_csr.rm = oldrm;
2332 			rfmt = w_fmt;
2333 			goto copcsr;
2334 
2335 		case fsel_op:
2336 			if (!cpu_has_mips_r6)
2337 				return SIGILL;
2338 
2339 			MIPS_FPU_EMU_INC_STATS(sel_d);
2340 			DPFROMREG(fd, MIPSInst_FD(ir));
2341 			if (fd.bits & 0x1)
2342 				DPFROMREG(rv.d, MIPSInst_FT(ir));
2343 			else
2344 				DPFROMREG(rv.d, MIPSInst_FS(ir));
2345 			break;
2346 
2347 		case fcvtl_op:
2348 			if (!cpu_has_mips_3_4_5_64_r2_r6)
2349 				return SIGILL;
2350 
2351 			MIPS_FPU_EMU_INC_STATS(cvt_l_d);
2352 			DPFROMREG(fs, MIPSInst_FS(ir));
2353 			rv.l = ieee754dp_tlong(fs);
2354 			rfmt = l_fmt;
2355 			goto copcsr;
2356 
2357 		case froundl_op:
2358 		case ftruncl_op:
2359 		case fceill_op:
2360 		case ffloorl_op:
2361 			if (!cpu_has_mips_3_4_5_64_r2_r6)
2362 				return SIGILL;
2363 
2364 			if (MIPSInst_FUNC(ir) == fceill_op)
2365 				MIPS_FPU_EMU_INC_STATS(ceil_l_d);
2366 			if (MIPSInst_FUNC(ir) == ffloorl_op)
2367 				MIPS_FPU_EMU_INC_STATS(floor_l_d);
2368 			if (MIPSInst_FUNC(ir) == froundl_op)
2369 				MIPS_FPU_EMU_INC_STATS(round_l_d);
2370 			if (MIPSInst_FUNC(ir) == ftruncl_op)
2371 				MIPS_FPU_EMU_INC_STATS(trunc_l_d);
2372 
2373 			oldrm = ieee754_csr.rm;
2374 			DPFROMREG(fs, MIPSInst_FS(ir));
2375 			ieee754_csr.rm = MIPSInst_FUNC(ir);
2376 			rv.l = ieee754dp_tlong(fs);
2377 			ieee754_csr.rm = oldrm;
2378 			rfmt = l_fmt;
2379 			goto copcsr;
2380 
2381 		default:
2382 			if (!NO_R6EMU && MIPSInst_FUNC(ir) >= fcmp_op) {
2383 				unsigned int cmpop;
2384 				union ieee754dp fs, ft;
2385 
2386 				cmpop = MIPSInst_FUNC(ir) - fcmp_op;
2387 				DPFROMREG(fs, MIPSInst_FS(ir));
2388 				DPFROMREG(ft, MIPSInst_FT(ir));
2389 				rv.w = ieee754dp_cmp(fs, ft,
2390 					cmptab[cmpop & 0x7], cmpop & 0x8);
2391 				rfmt = -1;
2392 				if ((cmpop & 0x8)
2393 					&&
2394 					ieee754_cxtest
2395 					(IEEE754_INVALID_OPERATION))
2396 					rcsr = FPU_CSR_INV_X | FPU_CSR_INV_S;
2397 				else
2398 					goto copcsr;
2399 
2400 			}
2401 			else {
2402 				return SIGILL;
2403 			}
2404 			break;
2405 		}
2406 		break;
2407 	}
2408 
2409 	case w_fmt: {
2410 		union ieee754dp fs;
2411 
2412 		switch (MIPSInst_FUNC(ir)) {
2413 		case fcvts_op:
2414 			/* convert word to single precision real */
2415 			MIPS_FPU_EMU_INC_STATS(cvt_s_w);
2416 			SPFROMREG(fs, MIPSInst_FS(ir));
2417 			rv.s = ieee754sp_fint(fs.bits);
2418 			rfmt = s_fmt;
2419 			goto copcsr;
2420 		case fcvtd_op:
2421 			/* convert word to double precision real */
2422 			MIPS_FPU_EMU_INC_STATS(cvt_d_w);
2423 			SPFROMREG(fs, MIPSInst_FS(ir));
2424 			rv.d = ieee754dp_fint(fs.bits);
2425 			rfmt = d_fmt;
2426 			goto copcsr;
2427 		default: {
2428 			/* Emulating the new CMP.condn.fmt R6 instruction */
2429 #define CMPOP_MASK	0x7
2430 #define SIGN_BIT	(0x1 << 3)
2431 #define PREDICATE_BIT	(0x1 << 4)
2432 
2433 			int cmpop = MIPSInst_FUNC(ir) & CMPOP_MASK;
2434 			int sig = MIPSInst_FUNC(ir) & SIGN_BIT;
2435 			union ieee754sp fs, ft;
2436 
2437 			/* This is an R6 only instruction */
2438 			if (!cpu_has_mips_r6 ||
2439 			    (MIPSInst_FUNC(ir) & 0x20))
2440 				return SIGILL;
2441 
2442 			if (!sig) {
2443 				if (!(MIPSInst_FUNC(ir) & PREDICATE_BIT)) {
2444 					switch (cmpop) {
2445 					case 0:
2446 					MIPS_FPU_EMU_INC_STATS(cmp_af_s);
2447 					break;
2448 					case 1:
2449 					MIPS_FPU_EMU_INC_STATS(cmp_un_s);
2450 					break;
2451 					case 2:
2452 					MIPS_FPU_EMU_INC_STATS(cmp_eq_s);
2453 					break;
2454 					case 3:
2455 					MIPS_FPU_EMU_INC_STATS(cmp_ueq_s);
2456 					break;
2457 					case 4:
2458 					MIPS_FPU_EMU_INC_STATS(cmp_lt_s);
2459 					break;
2460 					case 5:
2461 					MIPS_FPU_EMU_INC_STATS(cmp_ult_s);
2462 					break;
2463 					case 6:
2464 					MIPS_FPU_EMU_INC_STATS(cmp_le_s);
2465 					break;
2466 					case 7:
2467 					MIPS_FPU_EMU_INC_STATS(cmp_ule_s);
2468 					break;
2469 					}
2470 				} else {
2471 					switch (cmpop) {
2472 					case 1:
2473 					MIPS_FPU_EMU_INC_STATS(cmp_or_s);
2474 					break;
2475 					case 2:
2476 					MIPS_FPU_EMU_INC_STATS(cmp_une_s);
2477 					break;
2478 					case 3:
2479 					MIPS_FPU_EMU_INC_STATS(cmp_ne_s);
2480 					break;
2481 					}
2482 				}
2483 			} else {
2484 				if (!(MIPSInst_FUNC(ir) & PREDICATE_BIT)) {
2485 					switch (cmpop) {
2486 					case 0:
2487 					MIPS_FPU_EMU_INC_STATS(cmp_saf_s);
2488 					break;
2489 					case 1:
2490 					MIPS_FPU_EMU_INC_STATS(cmp_sun_s);
2491 					break;
2492 					case 2:
2493 					MIPS_FPU_EMU_INC_STATS(cmp_seq_s);
2494 					break;
2495 					case 3:
2496 					MIPS_FPU_EMU_INC_STATS(cmp_sueq_s);
2497 					break;
2498 					case 4:
2499 					MIPS_FPU_EMU_INC_STATS(cmp_slt_s);
2500 					break;
2501 					case 5:
2502 					MIPS_FPU_EMU_INC_STATS(cmp_sult_s);
2503 					break;
2504 					case 6:
2505 					MIPS_FPU_EMU_INC_STATS(cmp_sle_s);
2506 					break;
2507 					case 7:
2508 					MIPS_FPU_EMU_INC_STATS(cmp_sule_s);
2509 					break;
2510 					}
2511 				} else {
2512 					switch (cmpop) {
2513 					case 1:
2514 					MIPS_FPU_EMU_INC_STATS(cmp_sor_s);
2515 					break;
2516 					case 2:
2517 					MIPS_FPU_EMU_INC_STATS(cmp_sune_s);
2518 					break;
2519 					case 3:
2520 					MIPS_FPU_EMU_INC_STATS(cmp_sne_s);
2521 					break;
2522 					}
2523 				}
2524 			}
2525 
2526 			/* fmt is w_fmt for single precision so fix it */
2527 			rfmt = s_fmt;
2528 			/* default to false */
2529 			rv.w = 0;
2530 
2531 			/* CMP.condn.S */
2532 			SPFROMREG(fs, MIPSInst_FS(ir));
2533 			SPFROMREG(ft, MIPSInst_FT(ir));
2534 
2535 			/* positive predicates */
2536 			if (!(MIPSInst_FUNC(ir) & PREDICATE_BIT)) {
2537 				if (ieee754sp_cmp(fs, ft, cmptab[cmpop],
2538 						  sig))
2539 				    rv.w = -1; /* true, all 1s */
2540 				if ((sig) &&
2541 				    ieee754_cxtest(IEEE754_INVALID_OPERATION))
2542 					rcsr = FPU_CSR_INV_X | FPU_CSR_INV_S;
2543 				else
2544 					goto copcsr;
2545 			} else {
2546 				/* negative predicates */
2547 				switch (cmpop) {
2548 				case 1:
2549 				case 2:
2550 				case 3:
2551 					if (ieee754sp_cmp(fs, ft,
2552 							  negative_cmptab[cmpop],
2553 							  sig))
2554 						rv.w = -1; /* true, all 1s */
2555 					if (sig &&
2556 					    ieee754_cxtest(IEEE754_INVALID_OPERATION))
2557 						rcsr = FPU_CSR_INV_X | FPU_CSR_INV_S;
2558 					else
2559 						goto copcsr;
2560 					break;
2561 				default:
2562 					/* Reserved R6 ops */
2563 					return SIGILL;
2564 				}
2565 			}
2566 			break;
2567 			}
2568 		}
2569 		break;
2570 	}
2571 
2572 	case l_fmt:
2573 
2574 		if (!cpu_has_mips_3_4_5_64_r2_r6)
2575 			return SIGILL;
2576 
2577 		DIFROMREG(bits, MIPSInst_FS(ir));
2578 
2579 		switch (MIPSInst_FUNC(ir)) {
2580 		case fcvts_op:
2581 			/* convert long to single precision real */
2582 			MIPS_FPU_EMU_INC_STATS(cvt_s_l);
2583 			rv.s = ieee754sp_flong(bits);
2584 			rfmt = s_fmt;
2585 			goto copcsr;
2586 		case fcvtd_op:
2587 			/* convert long to double precision real */
2588 			MIPS_FPU_EMU_INC_STATS(cvt_d_l);
2589 			rv.d = ieee754dp_flong(bits);
2590 			rfmt = d_fmt;
2591 			goto copcsr;
2592 		default: {
2593 			/* Emulating the new CMP.condn.fmt R6 instruction */
2594 			int cmpop = MIPSInst_FUNC(ir) & CMPOP_MASK;
2595 			int sig = MIPSInst_FUNC(ir) & SIGN_BIT;
2596 			union ieee754dp fs, ft;
2597 
2598 			if (!cpu_has_mips_r6 ||
2599 			    (MIPSInst_FUNC(ir) & 0x20))
2600 				return SIGILL;
2601 
2602 			if (!sig) {
2603 				if (!(MIPSInst_FUNC(ir) & PREDICATE_BIT)) {
2604 					switch (cmpop) {
2605 					case 0:
2606 					MIPS_FPU_EMU_INC_STATS(cmp_af_d);
2607 					break;
2608 					case 1:
2609 					MIPS_FPU_EMU_INC_STATS(cmp_un_d);
2610 					break;
2611 					case 2:
2612 					MIPS_FPU_EMU_INC_STATS(cmp_eq_d);
2613 					break;
2614 					case 3:
2615 					MIPS_FPU_EMU_INC_STATS(cmp_ueq_d);
2616 					break;
2617 					case 4:
2618 					MIPS_FPU_EMU_INC_STATS(cmp_lt_d);
2619 					break;
2620 					case 5:
2621 					MIPS_FPU_EMU_INC_STATS(cmp_ult_d);
2622 					break;
2623 					case 6:
2624 					MIPS_FPU_EMU_INC_STATS(cmp_le_d);
2625 					break;
2626 					case 7:
2627 					MIPS_FPU_EMU_INC_STATS(cmp_ule_d);
2628 					break;
2629 					}
2630 				} else {
2631 					switch (cmpop) {
2632 					case 1:
2633 					MIPS_FPU_EMU_INC_STATS(cmp_or_d);
2634 					break;
2635 					case 2:
2636 					MIPS_FPU_EMU_INC_STATS(cmp_une_d);
2637 					break;
2638 					case 3:
2639 					MIPS_FPU_EMU_INC_STATS(cmp_ne_d);
2640 					break;
2641 					}
2642 				}
2643 			} else {
2644 				if (!(MIPSInst_FUNC(ir) & PREDICATE_BIT)) {
2645 					switch (cmpop) {
2646 					case 0:
2647 					MIPS_FPU_EMU_INC_STATS(cmp_saf_d);
2648 					break;
2649 					case 1:
2650 					MIPS_FPU_EMU_INC_STATS(cmp_sun_d);
2651 					break;
2652 					case 2:
2653 					MIPS_FPU_EMU_INC_STATS(cmp_seq_d);
2654 					break;
2655 					case 3:
2656 					MIPS_FPU_EMU_INC_STATS(cmp_sueq_d);
2657 					break;
2658 					case 4:
2659 					MIPS_FPU_EMU_INC_STATS(cmp_slt_d);
2660 					break;
2661 					case 5:
2662 					MIPS_FPU_EMU_INC_STATS(cmp_sult_d);
2663 					break;
2664 					case 6:
2665 					MIPS_FPU_EMU_INC_STATS(cmp_sle_d);
2666 					break;
2667 					case 7:
2668 					MIPS_FPU_EMU_INC_STATS(cmp_sule_d);
2669 					break;
2670 					}
2671 				} else {
2672 					switch (cmpop) {
2673 					case 1:
2674 					MIPS_FPU_EMU_INC_STATS(cmp_sor_d);
2675 					break;
2676 					case 2:
2677 					MIPS_FPU_EMU_INC_STATS(cmp_sune_d);
2678 					break;
2679 					case 3:
2680 					MIPS_FPU_EMU_INC_STATS(cmp_sne_d);
2681 					break;
2682 					}
2683 				}
2684 			}
2685 
2686 			/* fmt is l_fmt for double precision so fix it */
2687 			rfmt = d_fmt;
2688 			/* default to false */
2689 			rv.l = 0;
2690 
2691 			/* CMP.condn.D */
2692 			DPFROMREG(fs, MIPSInst_FS(ir));
2693 			DPFROMREG(ft, MIPSInst_FT(ir));
2694 
2695 			/* positive predicates */
2696 			if (!(MIPSInst_FUNC(ir) & PREDICATE_BIT)) {
2697 				if (ieee754dp_cmp(fs, ft,
2698 						  cmptab[cmpop], sig))
2699 				    rv.l = -1LL; /* true, all 1s */
2700 				if (sig &&
2701 				    ieee754_cxtest(IEEE754_INVALID_OPERATION))
2702 					rcsr = FPU_CSR_INV_X | FPU_CSR_INV_S;
2703 				else
2704 					goto copcsr;
2705 			} else {
2706 				/* negative predicates */
2707 				switch (cmpop) {
2708 				case 1:
2709 				case 2:
2710 				case 3:
2711 					if (ieee754dp_cmp(fs, ft,
2712 							  negative_cmptab[cmpop],
2713 							  sig))
2714 						rv.l = -1LL; /* true, all 1s */
2715 					if (sig &&
2716 					    ieee754_cxtest(IEEE754_INVALID_OPERATION))
2717 						rcsr = FPU_CSR_INV_X | FPU_CSR_INV_S;
2718 					else
2719 						goto copcsr;
2720 					break;
2721 				default:
2722 					/* Reserved R6 ops */
2723 					return SIGILL;
2724 				}
2725 			}
2726 			break;
2727 			}
2728 		}
2729 		break;
2730 
2731 	default:
2732 		return SIGILL;
2733 	}
2734 
2735 	/*
2736 	 * Update the fpu CSR register for this operation.
2737 	 * If an exception is required, generate a tidy SIGFPE exception,
2738 	 * without updating the result register.
2739 	 * Note: cause exception bits do not accumulate, they are rewritten
2740 	 * for each op; only the flag/sticky bits accumulate.
2741 	 */
2742 	ctx->fcr31 = (ctx->fcr31 & ~FPU_CSR_ALL_X) | rcsr;
2743 	if ((ctx->fcr31 >> 5) & ctx->fcr31 & FPU_CSR_ALL_E) {
2744 		/*printk ("SIGFPE: FPU csr = %08x\n",ctx->fcr31); */
2745 		return SIGFPE;
2746 	}
2747 
2748 	/*
2749 	 * Now we can safely write the result back to the register file.
2750 	 */
2751 	switch (rfmt) {
2752 	case -1:
2753 
2754 		if (cpu_has_mips_4_5_r)
2755 			cbit = fpucondbit[MIPSInst_FD(ir) >> 2];
2756 		else
2757 			cbit = FPU_CSR_COND;
2758 		if (rv.w)
2759 			ctx->fcr31 |= cbit;
2760 		else
2761 			ctx->fcr31 &= ~cbit;
2762 		break;
2763 
2764 	case d_fmt:
2765 		DPTOREG(rv.d, MIPSInst_FD(ir));
2766 		break;
2767 	case s_fmt:
2768 		SPTOREG(rv.s, MIPSInst_FD(ir));
2769 		break;
2770 	case w_fmt:
2771 		SITOREG(rv.w, MIPSInst_FD(ir));
2772 		break;
2773 	case l_fmt:
2774 		if (!cpu_has_mips_3_4_5_64_r2_r6)
2775 			return SIGILL;
2776 
2777 		DITOREG(rv.l, MIPSInst_FD(ir));
2778 		break;
2779 	default:
2780 		return SIGILL;
2781 	}
2782 
2783 	return 0;
2784 }
2785 
2786 /*
2787  * Emulate FPU instructions.
2788  *
2789  * If we use FPU hardware, then we have been typically called to handle
2790  * an unimplemented operation, such as where an operand is a NaN or
2791  * denormalized.  In that case exit the emulation loop after a single
2792  * iteration so as to let hardware execute any subsequent instructions.
2793  *
2794  * If we have no FPU hardware or it has been disabled, then continue
2795  * emulating floating-point instructions until one of these conditions
2796  * has occurred:
2797  *
2798  * - a non-FPU instruction has been encountered,
2799  *
2800  * - an attempt to emulate has ended with a signal,
2801  *
2802  * - the ISA mode has been switched.
2803  *
2804  * We need to terminate the emulation loop if we got switched to the
2805  * MIPS16 mode, whether supported or not, so that we do not attempt
2806  * to emulate a MIPS16 instruction as a regular MIPS FPU instruction.
2807  * Similarly if we got switched to the microMIPS mode and only the
2808  * regular MIPS mode is supported, so that we do not attempt to emulate
2809  * a microMIPS instruction as a regular MIPS FPU instruction.  Or if
2810  * we got switched to the regular MIPS mode and only the microMIPS mode
2811  * is supported, so that we do not attempt to emulate a regular MIPS
2812  * instruction that should cause an Address Error exception instead.
2813  * For simplicity we always terminate upon an ISA mode switch.
2814  */
2815 int fpu_emulator_cop1Handler(struct pt_regs *xcp, struct mips_fpu_struct *ctx,
2816 	int has_fpu, void __user **fault_addr)
2817 {
2818 	unsigned long oldepc, prevepc;
2819 	struct mm_decoded_insn dec_insn;
2820 	u16 instr[4];
2821 	u16 *instr_ptr;
2822 	int sig = 0;
2823 
2824 	oldepc = xcp->cp0_epc;
2825 	do {
2826 		prevepc = xcp->cp0_epc;
2827 
2828 		if (get_isa16_mode(prevepc) && cpu_has_mmips) {
2829 			/*
2830 			 * Get next 2 microMIPS instructions and convert them
2831 			 * into 32-bit instructions.
2832 			 */
2833 			if ((get_user(instr[0], (u16 __user *)msk_isa16_mode(xcp->cp0_epc))) ||
2834 			    (get_user(instr[1], (u16 __user *)msk_isa16_mode(xcp->cp0_epc + 2))) ||
2835 			    (get_user(instr[2], (u16 __user *)msk_isa16_mode(xcp->cp0_epc + 4))) ||
2836 			    (get_user(instr[3], (u16 __user *)msk_isa16_mode(xcp->cp0_epc + 6)))) {
2837 				MIPS_FPU_EMU_INC_STATS(errors);
2838 				return SIGBUS;
2839 			}
2840 			instr_ptr = instr;
2841 
2842 			/* Get first instruction. */
2843 			if (mm_insn_16bit(*instr_ptr)) {
2844 				/* Duplicate the half-word. */
2845 				dec_insn.insn = (*instr_ptr << 16) |
2846 					(*instr_ptr);
2847 				/* 16-bit instruction. */
2848 				dec_insn.pc_inc = 2;
2849 				instr_ptr += 1;
2850 			} else {
2851 				dec_insn.insn = (*instr_ptr << 16) |
2852 					*(instr_ptr+1);
2853 				/* 32-bit instruction. */
2854 				dec_insn.pc_inc = 4;
2855 				instr_ptr += 2;
2856 			}
2857 			/* Get second instruction. */
2858 			if (mm_insn_16bit(*instr_ptr)) {
2859 				/* Duplicate the half-word. */
2860 				dec_insn.next_insn = (*instr_ptr << 16) |
2861 					(*instr_ptr);
2862 				/* 16-bit instruction. */
2863 				dec_insn.next_pc_inc = 2;
2864 			} else {
2865 				dec_insn.next_insn = (*instr_ptr << 16) |
2866 					*(instr_ptr+1);
2867 				/* 32-bit instruction. */
2868 				dec_insn.next_pc_inc = 4;
2869 			}
2870 			dec_insn.micro_mips_mode = 1;
2871 		} else {
2872 			if ((get_user(dec_insn.insn,
2873 			    (mips_instruction __user *) xcp->cp0_epc)) ||
2874 			    (get_user(dec_insn.next_insn,
2875 			    (mips_instruction __user *)(xcp->cp0_epc+4)))) {
2876 				MIPS_FPU_EMU_INC_STATS(errors);
2877 				return SIGBUS;
2878 			}
2879 			dec_insn.pc_inc = 4;
2880 			dec_insn.next_pc_inc = 4;
2881 			dec_insn.micro_mips_mode = 0;
2882 		}
2883 
2884 		if ((dec_insn.insn == 0) ||
2885 		   ((dec_insn.pc_inc == 2) &&
2886 		   ((dec_insn.insn & 0xffff) == MM_NOP16)))
2887 			xcp->cp0_epc += dec_insn.pc_inc;	/* Skip NOPs */
2888 		else {
2889 			/*
2890 			 * The 'ieee754_csr' is an alias of ctx->fcr31.
2891 			 * No need to copy ctx->fcr31 to ieee754_csr.
2892 			 */
2893 			sig = cop1Emulate(xcp, ctx, dec_insn, fault_addr);
2894 		}
2895 
2896 		if (has_fpu)
2897 			break;
2898 		if (sig)
2899 			break;
2900 		/*
2901 		 * We have to check for the ISA bit explicitly here,
2902 		 * because `get_isa16_mode' may return 0 if support
2903 		 * for code compression has been globally disabled,
2904 		 * or otherwise we may produce the wrong signal or
2905 		 * even proceed successfully where we must not.
2906 		 */
2907 		if ((xcp->cp0_epc ^ prevepc) & 0x1)
2908 			break;
2909 
2910 		cond_resched();
2911 	} while (xcp->cp0_epc > prevepc);
2912 
2913 	/* SIGILL indicates a non-fpu instruction */
2914 	if (sig == SIGILL && xcp->cp0_epc != oldepc)
2915 		/* but if EPC has advanced, then ignore it */
2916 		sig = 0;
2917 
2918 	return sig;
2919 }
2920