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Add linux-next specific files for 20110516
[linux-2.6/next.git] / arch / mips / math-emu / cp1emu.c
blobd32cb050311053a8e873ea470617b0ec17f13e26
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,
276 1, 0, xcp, 0);
277 MIPS_FPU_EMU_INC_STATS(emulated);
278 switch (MIPSInst_OPCODE(ir)) {
279 case ldc1_op:{
280 u64 __user *va = (u64 __user *) (xcp->regs[MIPSInst_RS(ir)] +
281 MIPSInst_SIMM(ir));
282 u64 val;
283
284 MIPS_FPU_EMU_INC_STATS(loads);
285
286 if (!access_ok(VERIFY_READ, va, sizeof(u64))) {
287 MIPS_FPU_EMU_INC_STATS(errors);
288 *fault_addr = va;
289 return SIGBUS;
290 }
291 if (__get_user(val, va)) {
292 MIPS_FPU_EMU_INC_STATS(errors);
293 *fault_addr = va;
294 return SIGSEGV;
295 }
296 DITOREG(val, MIPSInst_RT(ir));
297 break;
298 }
299
300 case sdc1_op:{
301 u64 __user *va = (u64 __user *) (xcp->regs[MIPSInst_RS(ir)] +
302 MIPSInst_SIMM(ir));
303 u64 val;
304
305 MIPS_FPU_EMU_INC_STATS(stores);
306 DIFROMREG(val, MIPSInst_RT(ir));
307 if (!access_ok(VERIFY_WRITE, va, sizeof(u64))) {
308 MIPS_FPU_EMU_INC_STATS(errors);
309 *fault_addr = va;
310 return SIGBUS;
311 }
312 if (__put_user(val, va)) {
313 MIPS_FPU_EMU_INC_STATS(errors);
314 *fault_addr = va;
315 return SIGSEGV;
316 }
317 break;
318 }
319
320 case lwc1_op:{
321 u32 __user *va = (u32 __user *) (xcp->regs[MIPSInst_RS(ir)] +
322 MIPSInst_SIMM(ir));
323 u32 val;
324
325 MIPS_FPU_EMU_INC_STATS(loads);
326 if (!access_ok(VERIFY_READ, va, sizeof(u32))) {
327 MIPS_FPU_EMU_INC_STATS(errors);
328 *fault_addr = va;
329 return SIGBUS;
330 }
331 if (__get_user(val, va)) {
332 MIPS_FPU_EMU_INC_STATS(errors);
333 *fault_addr = va;
334 return SIGSEGV;
335 }
336 SITOREG(val, MIPSInst_RT(ir));
337 break;
338 }
339
340 case swc1_op:{
341 u32 __user *va = (u32 __user *) (xcp->regs[MIPSInst_RS(ir)] +
342 MIPSInst_SIMM(ir));
343 u32 val;
344
345 MIPS_FPU_EMU_INC_STATS(stores);
346 SIFROMREG(val, MIPSInst_RT(ir));
347 if (!access_ok(VERIFY_WRITE, va, sizeof(u32))) {
348 MIPS_FPU_EMU_INC_STATS(errors);
349 *fault_addr = va;
350 return SIGBUS;
351 }
352 if (__put_user(val, va)) {
353 MIPS_FPU_EMU_INC_STATS(errors);
354 *fault_addr = va;
355 return SIGSEGV;
356 }
357 break;
358 }
359
360 case cop1_op:
361 switch (MIPSInst_RS(ir)) {
362
363 #if defined(__mips64)
364 case dmfc_op:
365 /* copregister fs -> gpr[rt] */
366 if (MIPSInst_RT(ir) != 0) {
367 DIFROMREG(xcp->regs[MIPSInst_RT(ir)],
368 MIPSInst_RD(ir));
369 }
370 break;
371
372 case dmtc_op:
373 /* copregister fs <- rt */
374 DITOREG(xcp->regs[MIPSInst_RT(ir)], MIPSInst_RD(ir));
375 break;
376 #endif
377
378 case mfc_op:
379 /* copregister rd -> gpr[rt] */
380 if (MIPSInst_RT(ir) != 0) {
381 SIFROMREG(xcp->regs[MIPSInst_RT(ir)],
382 MIPSInst_RD(ir));
383 }
384 break;
385
386 case mtc_op:
387 /* copregister rd <- rt */
388 SITOREG(xcp->regs[MIPSInst_RT(ir)], MIPSInst_RD(ir));
389 break;
390
391 case cfc_op:{
392 /* cop control register rd -> gpr[rt] */
393 u32 value;
394
395 if (MIPSInst_RD(ir) == FPCREG_CSR) {
396 value = ctx->fcr31;
397 value = (value & ~FPU_CSR_RM) |
398 mips_rm[modeindex(value)];
399 #ifdef CSRTRACE
400 printk("%p gpr[%d]<-csr=%08x\n",
401 (void *) (xcp->cp0_epc),
402 MIPSInst_RT(ir), value);
403 #endif
404 }
405 else if (MIPSInst_RD(ir) == FPCREG_RID)
406 value = 0;
407 else
408 value = 0;
409 if (MIPSInst_RT(ir))
410 xcp->regs[MIPSInst_RT(ir)] = value;
411 break;
412 }
413
414 case ctc_op:{
415 /* copregister rd <- rt */
416 u32 value;
417
418 if (MIPSInst_RT(ir) == 0)
419 value = 0;
420 else
421 value = xcp->regs[MIPSInst_RT(ir)];
422
423 /* we only have one writable control reg
424 */
425 if (MIPSInst_RD(ir) == FPCREG_CSR) {
426 #ifdef CSRTRACE
427 printk("%p gpr[%d]->csr=%08x\n",
428 (void *) (xcp->cp0_epc),
429 MIPSInst_RT(ir), value);
430 #endif
431
432 /*
433 * Don't write reserved bits,
434 * and convert to ieee library modes
435 */
436 ctx->fcr31 = (value &
437 ~(FPU_CSR_RSVD | FPU_CSR_RM)) |
438 ieee_rm[modeindex(value)];
439 }
440 if ((ctx->fcr31 >> 5) & ctx->fcr31 & FPU_CSR_ALL_E) {
441 return SIGFPE;
442 }
443 break;
444 }
445
446 case bc_op:{
447 int likely = 0;
448
449 if (xcp->cp0_cause & CAUSEF_BD)
450 return SIGILL;
451
452 #if __mips >= 4
453 cond = ctx->fcr31 & fpucondbit[MIPSInst_RT(ir) >> 2];
454 #else
455 cond = ctx->fcr31 & FPU_CSR_COND;
456 #endif
457 switch (MIPSInst_RT(ir) & 3) {
458 case bcfl_op:
459 likely = 1;
460 case bcf_op:
461 cond = !cond;
462 break;
463 case bctl_op:
464 likely = 1;
465 case bct_op:
466 break;
467 default:
468 /* thats an illegal instruction */
469 return SIGILL;
470 }
471
472 xcp->cp0_cause |= CAUSEF_BD;
473 if (cond) {
474 /* branch taken: emulate dslot
475 * instruction
476 */
477 xcp->cp0_epc += 4;
478 contpc = (xcp->cp0_epc +
479 (MIPSInst_SIMM(ir) << 2));
480
481 if (!access_ok(VERIFY_READ, xcp->cp0_epc,
482 sizeof(mips_instruction))) {
483 MIPS_FPU_EMU_INC_STATS(errors);
484 *fault_addr = (mips_instruction __user *)xcp->cp0_epc;
485 return SIGBUS;
486 }
487 if (__get_user(ir,
488 (mips_instruction __user *) xcp->cp0_epc)) {
489 MIPS_FPU_EMU_INC_STATS(errors);
490 *fault_addr = (mips_instruction __user *)xcp->cp0_epc;
491 return SIGSEGV;
492 }
493
494 switch (MIPSInst_OPCODE(ir)) {
495 case lwc1_op:
496 case swc1_op:
497 #if (__mips >= 2 || defined(__mips64))
498 case ldc1_op:
499 case sdc1_op:
500 #endif
501 case cop1_op:
502 #if __mips >= 4 && __mips != 32
503 case cop1x_op:
504 #endif
505 /* its one of ours */
506 goto emul;
507 #if __mips >= 4
508 case spec_op:
509 if (MIPSInst_FUNC(ir) == movc_op)
510 goto emul;
511 break;
512 #endif
513 }
514
515 /*
516 * Single step the non-cp1
517 * instruction in the dslot
518 */
519 return mips_dsemul(xcp, ir, contpc);
520 }
521 else {
522 /* branch not taken */
523 if (likely) {
524 /*
525 * branch likely nullifies
526 * dslot if not taken
527 */
528 xcp->cp0_epc += 4;
529 contpc += 4;
530 /*
531 * else continue & execute
532 * dslot as normal insn
533 */
534 }
535 }
536 break;
537 }
538
539 default:
540 if (!(MIPSInst_RS(ir) & 0x10))
541 return SIGILL;
542 {
543 int sig;
544
545 /* a real fpu computation instruction */
546 if ((sig = fpu_emu(xcp, ctx, ir)))
547 return sig;
548 }
549 }
550 break;
551
552 #if __mips >= 4 && __mips != 32
553 case cop1x_op:{
554 int sig = fpux_emu(xcp, ctx, ir, fault_addr);
555 if (sig)
556 return sig;
557 break;
558 }
559 #endif
560
561 #if __mips >= 4
562 case spec_op:
563 if (MIPSInst_FUNC(ir) != movc_op)
564 return SIGILL;
565 cond = fpucondbit[MIPSInst_RT(ir) >> 2];
566 if (((ctx->fcr31 & cond) != 0) == ((MIPSInst_RT(ir) & 1) != 0))
567 xcp->regs[MIPSInst_RD(ir)] =
568 xcp->regs[MIPSInst_RS(ir)];
569 break;
570 #endif
571
572 default:
573 return SIGILL;
574 }
575
576 /* we did it !! */
577 xcp->cp0_epc = contpc;
578 xcp->cp0_cause &= ~CAUSEF_BD;
579
580 return 0;
581 }
582
583 /*
584 * Conversion table from MIPS compare ops 48-63
585 * cond = ieee754dp_cmp(x,y,IEEE754_UN,sig);
586 */
587 static const unsigned char cmptab[8] = {
588 0, /* cmp_0 (sig) cmp_sf */
589 IEEE754_CUN, /* cmp_un (sig) cmp_ngle */
590 IEEE754_CEQ, /* cmp_eq (sig) cmp_seq */
591 IEEE754_CEQ | IEEE754_CUN, /* cmp_ueq (sig) cmp_ngl */
592 IEEE754_CLT, /* cmp_olt (sig) cmp_lt */
593 IEEE754_CLT | IEEE754_CUN, /* cmp_ult (sig) cmp_nge */
594 IEEE754_CLT | IEEE754_CEQ, /* cmp_ole (sig) cmp_le */
595 IEEE754_CLT | IEEE754_CEQ | IEEE754_CUN, /* cmp_ule (sig) cmp_ngt */
596 };
597
598
599 #if __mips >= 4 && __mips != 32
600
601 /*
602 * Additional MIPS4 instructions
603 */
604
605 #define DEF3OP(name, p, f1, f2, f3) \
606 static ieee754##p fpemu_##p##_##name(ieee754##p r, ieee754##p s, \
607 ieee754##p t) \
608 { \
609 struct _ieee754_csr ieee754_csr_save; \
610 s = f1(s, t); \
611 ieee754_csr_save = ieee754_csr; \
612 s = f2(s, r); \
613 ieee754_csr_save.cx |= ieee754_csr.cx; \
614 ieee754_csr_save.sx |= ieee754_csr.sx; \
615 s = f3(s); \
616 ieee754_csr.cx |= ieee754_csr_save.cx; \
617 ieee754_csr.sx |= ieee754_csr_save.sx; \
618 return s; \
619 }
620
621 static ieee754dp fpemu_dp_recip(ieee754dp d)
622 {
623 return ieee754dp_div(ieee754dp_one(0), d);
624 }
625
626 static ieee754dp fpemu_dp_rsqrt(ieee754dp d)
627 {
628 return ieee754dp_div(ieee754dp_one(0), ieee754dp_sqrt(d));
629 }
630
631 static ieee754sp fpemu_sp_recip(ieee754sp s)
632 {
633 return ieee754sp_div(ieee754sp_one(0), s);
634 }
635
636 static ieee754sp fpemu_sp_rsqrt(ieee754sp s)
637 {
638 return ieee754sp_div(ieee754sp_one(0), ieee754sp_sqrt(s));
639 }
640
641 DEF3OP(madd, sp, ieee754sp_mul, ieee754sp_add, );
642 DEF3OP(msub, sp, ieee754sp_mul, ieee754sp_sub, );
643 DEF3OP(nmadd, sp, ieee754sp_mul, ieee754sp_add, ieee754sp_neg);
644 DEF3OP(nmsub, sp, ieee754sp_mul, ieee754sp_sub, ieee754sp_neg);
645 DEF3OP(madd, dp, ieee754dp_mul, ieee754dp_add, );
646 DEF3OP(msub, dp, ieee754dp_mul, ieee754dp_sub, );
647 DEF3OP(nmadd, dp, ieee754dp_mul, ieee754dp_add, ieee754dp_neg);
648 DEF3OP(nmsub, dp, ieee754dp_mul, ieee754dp_sub, ieee754dp_neg);
649
650 static int fpux_emu(struct pt_regs *xcp, struct mips_fpu_struct *ctx,
651 mips_instruction ir, void *__user *fault_addr)
652 {
653 unsigned rcsr = 0; /* resulting csr */
654
655 MIPS_FPU_EMU_INC_STATS(cp1xops);
656
657 switch (MIPSInst_FMA_FFMT(ir)) {
658 case s_fmt:{ /* 0 */
659
660 ieee754sp(*handler) (ieee754sp, ieee754sp, ieee754sp);
661 ieee754sp fd, fr, fs, ft;
662 u32 __user *va;
663 u32 val;
664
665 switch (MIPSInst_FUNC(ir)) {
666 case lwxc1_op:
667 va = (void __user *) (xcp->regs[MIPSInst_FR(ir)] +
668 xcp->regs[MIPSInst_FT(ir)]);
669
670 MIPS_FPU_EMU_INC_STATS(loads);
671 if (!access_ok(VERIFY_READ, va, sizeof(u32))) {
672 MIPS_FPU_EMU_INC_STATS(errors);
673 *fault_addr = va;
674 return SIGBUS;
675 }
676 if (__get_user(val, va)) {
677 MIPS_FPU_EMU_INC_STATS(errors);
678 *fault_addr = va;
679 return SIGSEGV;
680 }
681 SITOREG(val, MIPSInst_FD(ir));
682 break;
683
684 case swxc1_op:
685 va = (void __user *) (xcp->regs[MIPSInst_FR(ir)] +
686 xcp->regs[MIPSInst_FT(ir)]);
687
688 MIPS_FPU_EMU_INC_STATS(stores);
689
690 SIFROMREG(val, MIPSInst_FS(ir));
691 if (!access_ok(VERIFY_WRITE, va, sizeof(u32))) {
692 MIPS_FPU_EMU_INC_STATS(errors);
693 *fault_addr = va;
694 return SIGBUS;
695 }
696 if (put_user(val, va)) {
697 MIPS_FPU_EMU_INC_STATS(errors);
698 *fault_addr = va;
699 return SIGSEGV;
700 }
701 break;
702
703 case madd_s_op:
704 handler = fpemu_sp_madd;
705 goto scoptop;
706 case msub_s_op:
707 handler = fpemu_sp_msub;
708 goto scoptop;
709 case nmadd_s_op:
710 handler = fpemu_sp_nmadd;
711 goto scoptop;
712 case nmsub_s_op:
713 handler = fpemu_sp_nmsub;
714 goto scoptop;
715
716 scoptop:
717 SPFROMREG(fr, MIPSInst_FR(ir));
718 SPFROMREG(fs, MIPSInst_FS(ir));
719 SPFROMREG(ft, MIPSInst_FT(ir));
720 fd = (*handler) (fr, fs, ft);
721 SPTOREG(fd, MIPSInst_FD(ir));
722
723 copcsr:
724 if (ieee754_cxtest(IEEE754_INEXACT))
725 rcsr |= FPU_CSR_INE_X | FPU_CSR_INE_S;
726 if (ieee754_cxtest(IEEE754_UNDERFLOW))
727 rcsr |= FPU_CSR_UDF_X | FPU_CSR_UDF_S;
728 if (ieee754_cxtest(IEEE754_OVERFLOW))
729 rcsr |= FPU_CSR_OVF_X | FPU_CSR_OVF_S;
730 if (ieee754_cxtest(IEEE754_INVALID_OPERATION))
731 rcsr |= FPU_CSR_INV_X | FPU_CSR_INV_S;
732
733 ctx->fcr31 = (ctx->fcr31 & ~FPU_CSR_ALL_X) | rcsr;
734 if ((ctx->fcr31 >> 5) & ctx->fcr31 & FPU_CSR_ALL_E) {
735 /*printk ("SIGFPE: fpu csr = %08x\n",
736 ctx->fcr31); */
737 return SIGFPE;
738 }
739
740 break;
741
742 default:
743 return SIGILL;
744 }
745 break;
746 }
747
748 case d_fmt:{ /* 1 */
749 ieee754dp(*handler) (ieee754dp, ieee754dp, ieee754dp);
750 ieee754dp fd, fr, fs, ft;
751 u64 __user *va;
752 u64 val;
753
754 switch (MIPSInst_FUNC(ir)) {
755 case ldxc1_op:
756 va = (void __user *) (xcp->regs[MIPSInst_FR(ir)] +
757 xcp->regs[MIPSInst_FT(ir)]);
758
759 MIPS_FPU_EMU_INC_STATS(loads);
760 if (!access_ok(VERIFY_READ, va, sizeof(u64))) {
761 MIPS_FPU_EMU_INC_STATS(errors);
762 *fault_addr = va;
763 return SIGBUS;
764 }
765 if (__get_user(val, va)) {
766 MIPS_FPU_EMU_INC_STATS(errors);
767 *fault_addr = va;
768 return SIGSEGV;
769 }
770 DITOREG(val, MIPSInst_FD(ir));
771 break;
772
773 case sdxc1_op:
774 va = (void __user *) (xcp->regs[MIPSInst_FR(ir)] +
775 xcp->regs[MIPSInst_FT(ir)]);
776
777 MIPS_FPU_EMU_INC_STATS(stores);
778 DIFROMREG(val, MIPSInst_FS(ir));
779 if (!access_ok(VERIFY_WRITE, va, sizeof(u64))) {
780 MIPS_FPU_EMU_INC_STATS(errors);
781 *fault_addr = va;
782 return SIGBUS;
783 }
784 if (__put_user(val, va)) {
785 MIPS_FPU_EMU_INC_STATS(errors);
786 *fault_addr = va;
787 return SIGSEGV;
788 }
789 break;
790
791 case madd_d_op:
792 handler = fpemu_dp_madd;
793 goto dcoptop;
794 case msub_d_op:
795 handler = fpemu_dp_msub;
796 goto dcoptop;
797 case nmadd_d_op:
798 handler = fpemu_dp_nmadd;
799 goto dcoptop;
800 case nmsub_d_op:
801 handler = fpemu_dp_nmsub;
802 goto dcoptop;
803
804 dcoptop:
805 DPFROMREG(fr, MIPSInst_FR(ir));
806 DPFROMREG(fs, MIPSInst_FS(ir));
807 DPFROMREG(ft, MIPSInst_FT(ir));
808 fd = (*handler) (fr, fs, ft);
809 DPTOREG(fd, MIPSInst_FD(ir));
810 goto copcsr;
811
812 default:
813 return SIGILL;
814 }
815 break;
816 }
817
818 case 0x7: /* 7 */
819 if (MIPSInst_FUNC(ir) != pfetch_op) {
820 return SIGILL;
821 }
822 /* ignore prefx operation */
823 break;
824
825 default:
826 return SIGILL;
827 }
828
829 return 0;
830 }
831 #endif
832
833
834
835 /*
836 * Emulate a single COP1 arithmetic instruction.
837 */
838 static int fpu_emu(struct pt_regs *xcp, struct mips_fpu_struct *ctx,
839 mips_instruction ir)
840 {
841 int rfmt; /* resulting format */
842 unsigned rcsr = 0; /* resulting csr */
843 unsigned cond;
844 union {
845 ieee754dp d;
846 ieee754sp s;
847 int w;
848 #ifdef __mips64
849 s64 l;
850 #endif
851 } rv; /* resulting value */
852
853 MIPS_FPU_EMU_INC_STATS(cp1ops);
854 switch (rfmt = (MIPSInst_FFMT(ir) & 0xf)) {
855 case s_fmt:{ /* 0 */
856 union {
857 ieee754sp(*b) (ieee754sp, ieee754sp);
858 ieee754sp(*u) (ieee754sp);
859 } handler;
860
861 switch (MIPSInst_FUNC(ir)) {
862 /* binary ops */
863 case fadd_op:
864 handler.b = ieee754sp_add;
865 goto scopbop;
866 case fsub_op:
867 handler.b = ieee754sp_sub;
868 goto scopbop;
869 case fmul_op:
870 handler.b = ieee754sp_mul;
871 goto scopbop;
872 case fdiv_op:
873 handler.b = ieee754sp_div;
874 goto scopbop;
875
876 /* unary ops */
877 #if __mips >= 2 || defined(__mips64)
878 case fsqrt_op:
879 handler.u = ieee754sp_sqrt;
880 goto scopuop;
881 #endif
882 #if __mips >= 4 && __mips != 32
883 case frsqrt_op:
884 handler.u = fpemu_sp_rsqrt;
885 goto scopuop;
886 case frecip_op:
887 handler.u = fpemu_sp_recip;
888 goto scopuop;
889 #endif
890 #if __mips >= 4
891 case fmovc_op:
892 cond = fpucondbit[MIPSInst_FT(ir) >> 2];
893 if (((ctx->fcr31 & cond) != 0) !=
894 ((MIPSInst_FT(ir) & 1) != 0))
895 return 0;
896 SPFROMREG(rv.s, MIPSInst_FS(ir));
897 break;
898 case fmovz_op:
899 if (xcp->regs[MIPSInst_FT(ir)] != 0)
900 return 0;
901 SPFROMREG(rv.s, MIPSInst_FS(ir));
902 break;
903 case fmovn_op:
904 if (xcp->regs[MIPSInst_FT(ir)] == 0)
905 return 0;
906 SPFROMREG(rv.s, MIPSInst_FS(ir));
907 break;
908 #endif
909 case fabs_op:
910 handler.u = ieee754sp_abs;
911 goto scopuop;
912 case fneg_op:
913 handler.u = ieee754sp_neg;
914 goto scopuop;
915 case fmov_op:
916 /* an easy one */
917 SPFROMREG(rv.s, MIPSInst_FS(ir));
918 goto copcsr;
919
920 /* binary op on handler */
921 scopbop:
922 {
923 ieee754sp fs, ft;
924
925 SPFROMREG(fs, MIPSInst_FS(ir));
926 SPFROMREG(ft, MIPSInst_FT(ir));
927
928 rv.s = (*handler.b) (fs, ft);
929 goto copcsr;
930 }
931 scopuop:
932 {
933 ieee754sp fs;
934
935 SPFROMREG(fs, MIPSInst_FS(ir));
936 rv.s = (*handler.u) (fs);
937 goto copcsr;
938 }
939 copcsr:
940 if (ieee754_cxtest(IEEE754_INEXACT))
941 rcsr |= FPU_CSR_INE_X | FPU_CSR_INE_S;
942 if (ieee754_cxtest(IEEE754_UNDERFLOW))
943 rcsr |= FPU_CSR_UDF_X | FPU_CSR_UDF_S;
944 if (ieee754_cxtest(IEEE754_OVERFLOW))
945 rcsr |= FPU_CSR_OVF_X | FPU_CSR_OVF_S;
946 if (ieee754_cxtest(IEEE754_ZERO_DIVIDE))
947 rcsr |= FPU_CSR_DIV_X | FPU_CSR_DIV_S;
948 if (ieee754_cxtest(IEEE754_INVALID_OPERATION))
949 rcsr |= FPU_CSR_INV_X | FPU_CSR_INV_S;
950 break;
951
952 /* unary conv ops */
953 case fcvts_op:
954 return SIGILL; /* not defined */
955 case fcvtd_op:{
956 ieee754sp fs;
957
958 SPFROMREG(fs, MIPSInst_FS(ir));
959 rv.d = ieee754dp_fsp(fs);
960 rfmt = d_fmt;
961 goto copcsr;
962 }
963 case fcvtw_op:{
964 ieee754sp fs;
965
966 SPFROMREG(fs, MIPSInst_FS(ir));
967 rv.w = ieee754sp_tint(fs);
968 rfmt = w_fmt;
969 goto copcsr;
970 }
971
972 #if __mips >= 2 || defined(__mips64)
973 case fround_op:
974 case ftrunc_op:
975 case fceil_op:
976 case ffloor_op:{
977 unsigned int oldrm = ieee754_csr.rm;
978 ieee754sp fs;
979
980 SPFROMREG(fs, MIPSInst_FS(ir));
981 ieee754_csr.rm = ieee_rm[modeindex(MIPSInst_FUNC(ir))];
982 rv.w = ieee754sp_tint(fs);
983 ieee754_csr.rm = oldrm;
984 rfmt = w_fmt;
985 goto copcsr;
986 }
987 #endif /* __mips >= 2 */
988
989 #if defined(__mips64)
990 case fcvtl_op:{
991 ieee754sp fs;
992
993 SPFROMREG(fs, MIPSInst_FS(ir));
994 rv.l = ieee754sp_tlong(fs);
995 rfmt = l_fmt;
996 goto copcsr;
997 }
998
999 case froundl_op:
1000 case ftruncl_op:
1001 case fceill_op:
1002 case ffloorl_op:{
1003 unsigned int oldrm = ieee754_csr.rm;
1004 ieee754sp fs;
1005
1006 SPFROMREG(fs, MIPSInst_FS(ir));
1007 ieee754_csr.rm = ieee_rm[modeindex(MIPSInst_FUNC(ir))];
1008 rv.l = ieee754sp_tlong(fs);
1009 ieee754_csr.rm = oldrm;
1010 rfmt = l_fmt;
1011 goto copcsr;
1012 }
1013 #endif /* defined(__mips64) */
1014
1015 default:
1016 if (MIPSInst_FUNC(ir) >= fcmp_op) {
1017 unsigned cmpop = MIPSInst_FUNC(ir) - fcmp_op;
1018 ieee754sp fs, ft;
1019
1020 SPFROMREG(fs, MIPSInst_FS(ir));
1021 SPFROMREG(ft, MIPSInst_FT(ir));
1022 rv.w = ieee754sp_cmp(fs, ft,
1023 cmptab[cmpop & 0x7], cmpop & 0x8);
1024 rfmt = -1;
1025 if ((cmpop & 0x8) && ieee754_cxtest
1026 (IEEE754_INVALID_OPERATION))
1027 rcsr = FPU_CSR_INV_X | FPU_CSR_INV_S;
1028 else
1029 goto copcsr;
1030
1031 }
1032 else {
1033 return SIGILL;
1034 }
1035 break;
1036 }
1037 break;
1038 }
1039
1040 case d_fmt:{
1041 union {
1042 ieee754dp(*b) (ieee754dp, ieee754dp);
1043 ieee754dp(*u) (ieee754dp);
1044 } handler;
1045
1046 switch (MIPSInst_FUNC(ir)) {
1047 /* binary ops */
1048 case fadd_op:
1049 handler.b = ieee754dp_add;
1050 goto dcopbop;
1051 case fsub_op:
1052 handler.b = ieee754dp_sub;
1053 goto dcopbop;
1054 case fmul_op:
1055 handler.b = ieee754dp_mul;
1056 goto dcopbop;
1057 case fdiv_op:
1058 handler.b = ieee754dp_div;
1059 goto dcopbop;
1060
1061 /* unary ops */
1062 #if __mips >= 2 || defined(__mips64)
1063 case fsqrt_op:
1064 handler.u = ieee754dp_sqrt;
1065 goto dcopuop;
1066 #endif
1067 #if __mips >= 4 && __mips != 32
1068 case frsqrt_op:
1069 handler.u = fpemu_dp_rsqrt;
1070 goto dcopuop;
1071 case frecip_op:
1072 handler.u = fpemu_dp_recip;
1073 goto dcopuop;
1074 #endif
1075 #if __mips >= 4
1076 case fmovc_op:
1077 cond = fpucondbit[MIPSInst_FT(ir) >> 2];
1078 if (((ctx->fcr31 & cond) != 0) !=
1079 ((MIPSInst_FT(ir) & 1) != 0))
1080 return 0;
1081 DPFROMREG(rv.d, MIPSInst_FS(ir));
1082 break;
1083 case fmovz_op:
1084 if (xcp->regs[MIPSInst_FT(ir)] != 0)
1085 return 0;
1086 DPFROMREG(rv.d, MIPSInst_FS(ir));
1087 break;
1088 case fmovn_op:
1089 if (xcp->regs[MIPSInst_FT(ir)] == 0)
1090 return 0;
1091 DPFROMREG(rv.d, MIPSInst_FS(ir));
1092 break;
1093 #endif
1094 case fabs_op:
1095 handler.u = ieee754dp_abs;
1096 goto dcopuop;
1097
1098 case fneg_op:
1099 handler.u = ieee754dp_neg;
1100 goto dcopuop;
1101
1102 case fmov_op:
1103 /* an easy one */
1104 DPFROMREG(rv.d, MIPSInst_FS(ir));
1105 goto copcsr;
1106
1107 /* binary op on handler */
1108 dcopbop:{
1109 ieee754dp fs, ft;
1110
1111 DPFROMREG(fs, MIPSInst_FS(ir));
1112 DPFROMREG(ft, MIPSInst_FT(ir));
1113
1114 rv.d = (*handler.b) (fs, ft);
1115 goto copcsr;
1116 }
1117 dcopuop:{
1118 ieee754dp fs;
1119
1120 DPFROMREG(fs, MIPSInst_FS(ir));
1121 rv.d = (*handler.u) (fs);
1122 goto copcsr;
1123 }
1124
1125 /* unary conv ops */
1126 case fcvts_op:{
1127 ieee754dp fs;
1128
1129 DPFROMREG(fs, MIPSInst_FS(ir));
1130 rv.s = ieee754sp_fdp(fs);
1131 rfmt = s_fmt;
1132 goto copcsr;
1133 }
1134 case fcvtd_op:
1135 return SIGILL; /* not defined */
1136
1137 case fcvtw_op:{
1138 ieee754dp fs;
1139
1140 DPFROMREG(fs, MIPSInst_FS(ir));
1141 rv.w = ieee754dp_tint(fs); /* wrong */
1142 rfmt = w_fmt;
1143 goto copcsr;
1144 }
1145
1146 #if __mips >= 2 || defined(__mips64)
1147 case fround_op:
1148 case ftrunc_op:
1149 case fceil_op:
1150 case ffloor_op:{
1151 unsigned int oldrm = ieee754_csr.rm;
1152 ieee754dp fs;
1153
1154 DPFROMREG(fs, MIPSInst_FS(ir));
1155 ieee754_csr.rm = ieee_rm[modeindex(MIPSInst_FUNC(ir))];
1156 rv.w = ieee754dp_tint(fs);
1157 ieee754_csr.rm = oldrm;
1158 rfmt = w_fmt;
1159 goto copcsr;
1160 }
1161 #endif
1162
1163 #if defined(__mips64)
1164 case fcvtl_op:{
1165 ieee754dp fs;
1166
1167 DPFROMREG(fs, MIPSInst_FS(ir));
1168 rv.l = ieee754dp_tlong(fs);
1169 rfmt = l_fmt;
1170 goto copcsr;
1171 }
1172
1173 case froundl_op:
1174 case ftruncl_op:
1175 case fceill_op:
1176 case ffloorl_op:{
1177 unsigned int oldrm = ieee754_csr.rm;
1178 ieee754dp fs;
1179
1180 DPFROMREG(fs, MIPSInst_FS(ir));
1181 ieee754_csr.rm = ieee_rm[modeindex(MIPSInst_FUNC(ir))];
1182 rv.l = ieee754dp_tlong(fs);
1183 ieee754_csr.rm = oldrm;
1184 rfmt = l_fmt;
1185 goto copcsr;
1186 }
1187 #endif /* __mips >= 3 */
1188
1189 default:
1190 if (MIPSInst_FUNC(ir) >= fcmp_op) {
1191 unsigned cmpop = MIPSInst_FUNC(ir) - fcmp_op;
1192 ieee754dp fs, ft;
1193
1194 DPFROMREG(fs, MIPSInst_FS(ir));
1195 DPFROMREG(ft, MIPSInst_FT(ir));
1196 rv.w = ieee754dp_cmp(fs, ft,
1197 cmptab[cmpop & 0x7], cmpop & 0x8);
1198 rfmt = -1;
1199 if ((cmpop & 0x8)
1200 &&
1201 ieee754_cxtest
1202 (IEEE754_INVALID_OPERATION))
1203 rcsr = FPU_CSR_INV_X | FPU_CSR_INV_S;
1204 else
1205 goto copcsr;
1206
1207 }
1208 else {
1209 return SIGILL;
1210 }
1211 break;
1212 }
1213 break;
1214 }
1215
1216 case w_fmt:{
1217 ieee754sp fs;
1218
1219 switch (MIPSInst_FUNC(ir)) {
1220 case fcvts_op:
1221 /* convert word to single precision real */
1222 SPFROMREG(fs, MIPSInst_FS(ir));
1223 rv.s = ieee754sp_fint(fs.bits);
1224 rfmt = s_fmt;
1225 goto copcsr;
1226 case fcvtd_op:
1227 /* convert word to double precision real */
1228 SPFROMREG(fs, MIPSInst_FS(ir));
1229 rv.d = ieee754dp_fint(fs.bits);
1230 rfmt = d_fmt;
1231 goto copcsr;
1232 default:
1233 return SIGILL;
1234 }
1235 break;
1236 }
1237
1238 #if defined(__mips64)
1239 case l_fmt:{
1240 switch (MIPSInst_FUNC(ir)) {
1241 case fcvts_op:
1242 /* convert long to single precision real */
1243 rv.s = ieee754sp_flong(ctx->fpr[MIPSInst_FS(ir)]);
1244 rfmt = s_fmt;
1245 goto copcsr;
1246 case fcvtd_op:
1247 /* convert long to double precision real */
1248 rv.d = ieee754dp_flong(ctx->fpr[MIPSInst_FS(ir)]);
1249 rfmt = d_fmt;
1250 goto copcsr;
1251 default:
1252 return SIGILL;
1253 }
1254 break;
1255 }
1256 #endif
1257
1258 default:
1259 return SIGILL;
1260 }
1261
1262 /*
1263 * Update the fpu CSR register for this operation.
1264 * If an exception is required, generate a tidy SIGFPE exception,
1265 * without updating the result register.
1266 * Note: cause exception bits do not accumulate, they are rewritten
1267 * for each op; only the flag/sticky bits accumulate.
1268 */
1269 ctx->fcr31 = (ctx->fcr31 & ~FPU_CSR_ALL_X) | rcsr;
1270 if ((ctx->fcr31 >> 5) & ctx->fcr31 & FPU_CSR_ALL_E) {
1271 /*printk ("SIGFPE: fpu csr = %08x\n",ctx->fcr31); */
1272 return SIGFPE;
1273 }
1274
1275 /*
1276 * Now we can safely write the result back to the register file.
1277 */
1278 switch (rfmt) {
1279 case -1:{
1280 #if __mips >= 4
1281 cond = fpucondbit[MIPSInst_FD(ir) >> 2];
1282 #else
1283 cond = FPU_CSR_COND;
1284 #endif
1285 if (rv.w)
1286 ctx->fcr31 |= cond;
1287 else
1288 ctx->fcr31 &= ~cond;
1289 break;
1290 }
1291 case d_fmt:
1292 DPTOREG(rv.d, MIPSInst_FD(ir));
1293 break;
1294 case s_fmt:
1295 SPTOREG(rv.s, MIPSInst_FD(ir));
1296 break;
1297 case w_fmt:
1298 SITOREG(rv.w, MIPSInst_FD(ir));
1299 break;
1300 #if defined(__mips64)
1301 case l_fmt:
1302 DITOREG(rv.l, MIPSInst_FD(ir));
1303 break;
1304 #endif
1305 default:
1306 return SIGILL;
1307 }
1308
1309 return 0;
1310 }
1311
1312 int fpu_emulator_cop1Handler(struct pt_regs *xcp, struct mips_fpu_struct *ctx,
1313 int has_fpu, void *__user *fault_addr)
1314 {
1315 unsigned long oldepc, prevepc;
1316 mips_instruction insn;
1317 int sig = 0;
1318
1319 oldepc = xcp->cp0_epc;
1320 do {
1321 prevepc = xcp->cp0_epc;
1322
1323 if (!access_ok(VERIFY_READ, xcp->cp0_epc, sizeof(mips_instruction))) {
1324 MIPS_FPU_EMU_INC_STATS(errors);
1325 *fault_addr = (mips_instruction __user *)xcp->cp0_epc;
1326 return SIGBUS;
1327 }
1328 if (__get_user(insn, (mips_instruction __user *) xcp->cp0_epc)) {
1329 MIPS_FPU_EMU_INC_STATS(errors);
1330 *fault_addr = (mips_instruction __user *)xcp->cp0_epc;
1331 return SIGSEGV;
1332 }
1333 if (insn == 0)
1334 xcp->cp0_epc += 4; /* skip nops */
1335 else {
1336 /*
1337 * The 'ieee754_csr' is an alias of
1338 * ctx->fcr31. No need to copy ctx->fcr31 to
1339 * ieee754_csr. But ieee754_csr.rm is ieee
1340 * library modes. (not mips rounding mode)
1341 */
1342 /* convert to ieee library modes */
1343 ieee754_csr.rm = ieee_rm[ieee754_csr.rm];
1344 sig = cop1Emulate(xcp, ctx, fault_addr);
1345 /* revert to mips rounding mode */
1346 ieee754_csr.rm = mips_rm[ieee754_csr.rm];
1347 }
1348
1349 if (has_fpu)
1350 break;
1351 if (sig)
1352 break;
1353
1354 cond_resched();
1355 } while (xcp->cp0_epc > prevepc);
1356
1357 /* SIGILL indicates a non-fpu instruction */
1358 if (sig == SIGILL && xcp->cp0_epc != oldepc)
1359 /* but if epc has advanced, then ignore it */
1360 sig = 0;
1361
1362 return sig;
1363 }
1364
1365 #ifdef CONFIG_DEBUG_FS
1366
1367 static int fpuemu_stat_get(void *data, u64 *val)
1368 {
1369 int cpu;
1370 unsigned long sum = 0;
1371 for_each_online_cpu(cpu) {
1372 struct mips_fpu_emulator_stats *ps;
1373 local_t *pv;
1374 ps = &per_cpu(fpuemustats, cpu);
1375 pv = (void *)ps + (unsigned long)data;
1376 sum += local_read(pv);
1377 }
1378 *val = sum;
1379 return 0;
1380 }
1381 DEFINE_SIMPLE_ATTRIBUTE(fops_fpuemu_stat, fpuemu_stat_get, NULL, "%llu\n");
1382
1383 extern struct dentry *mips_debugfs_dir;
1384 static int __init debugfs_fpuemu(void)
1385 {
1386 struct dentry *d, *dir;
1387
1388 if (!mips_debugfs_dir)
1389 return -ENODEV;
1390 dir = debugfs_create_dir("fpuemustats", mips_debugfs_dir);
1391 if (!dir)
1392 return -ENOMEM;
1393
1394 #define FPU_STAT_CREATE(M) \
1395 do { \
1396 d = debugfs_create_file(#M , S_IRUGO, dir, \
1397 (void *)offsetof(struct mips_fpu_emulator_stats, M), \
1398 &fops_fpuemu_stat); \
1399 if (!d) \
1400 return -ENOMEM; \
1401 } while (0)
1402
1403 FPU_STAT_CREATE(emulated);
1404 FPU_STAT_CREATE(loads);
1405 FPU_STAT_CREATE(stores);
1406 FPU_STAT_CREATE(cp1ops);
1407 FPU_STAT_CREATE(cp1xops);
1408 FPU_STAT_CREATE(errors);
1409
1410 return 0;
1411 }
1412 __initcall(debugfs_fpuemu);
1413 #endif
linux-next