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Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input
[linux-btrfs-devel.git] / arch / mips / math-emu / cp1emu.c
blobdbf2f93a50911b5914a295a82b3179c36562013f
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
62 static int fpu_emu(struct pt_regs *, struct mips_fpu_struct *,
63 mips_instruction);
64
65 #if __mips >= 4 && __mips != 32
66 static 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
73 DEFINE_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. */
85 static 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). */
92 static 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 */
101 static 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 */
120 static 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 */
179 static 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
211 static 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 */
586 static 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) \
605 static 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
620 static ieee754dp fpemu_dp_recip(ieee754dp d)
621 {
622 return ieee754dp_div(ieee754dp_one(0), d);
623 }
624
625 static ieee754dp fpemu_dp_rsqrt(ieee754dp d)
626 {
627 return ieee754dp_div(ieee754dp_one(0), ieee754dp_sqrt(d));
628 }
629
630 static ieee754sp fpemu_sp_recip(ieee754sp s)
631 {
632 return ieee754sp_div(ieee754sp_one(0), s);
633 }
634
635 static ieee754sp fpemu_sp_rsqrt(ieee754sp s)
636 {
637 return ieee754sp_div(ieee754sp_one(0), ieee754sp_sqrt(s));
638 }
639
640 DEF3OP(madd, sp, ieee754sp_mul, ieee754sp_add, );
641 DEF3OP(msub, sp, ieee754sp_mul, ieee754sp_sub, );
642 DEF3OP(nmadd, sp, ieee754sp_mul, ieee754sp_add, ieee754sp_neg);
643 DEF3OP(nmsub, sp, ieee754sp_mul, ieee754sp_sub, ieee754sp_neg);
644 DEF3OP(madd, dp, ieee754dp_mul, ieee754dp_add, );
645 DEF3OP(msub, dp, ieee754dp_mul, ieee754dp_sub, );
646 DEF3OP(nmadd, dp, ieee754dp_mul, ieee754dp_add, ieee754dp_neg);
647 DEF3OP(nmsub, dp, ieee754dp_mul, ieee754dp_sub, ieee754dp_neg);
648
649 static 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 */
837 static 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
1311 int 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
1366 static 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 }
1380 DEFINE_SIMPLE_ATTRIBUTE(fops_fpuemu_stat, fpuemu_stat_get, NULL, "%llu\n");
1381
1382 extern struct dentry *mips_debugfs_dir;
1383 static 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
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