1/*
2 * This file is subject to the terms and conditions of the GNU General Public
3 * License. See the file "COPYING" in the main directory of this archive
4 * for more details.
5 *
6 * Copyright (c) 2014 Imagination Technologies Ltd.
7 * Author: Leonid Yegoshin <Leonid.Yegoshin@imgtec.com>
8 * Author: Markos Chandras <markos.chandras@imgtec.com>
9 *
10 * MIPS R2 user space instruction emulator for MIPS R6
11 *
12 */
13#include <linux/bug.h>
14#include <linux/compiler.h>
15#include <linux/debugfs.h>
16#include <linux/init.h>
17#include <linux/kernel.h>
18#include <linux/ptrace.h>
19#include <linux/seq_file.h>
20
21#include <asm/asm.h>
22#include <asm/branch.h>
23#include <asm/break.h>
24#include <asm/debug.h>
25#include <asm/fpu.h>
26#include <asm/fpu_emulator.h>
27#include <asm/inst.h>
28#include <asm/mips-r2-to-r6-emul.h>
29#include <asm/local.h>
30#include <asm/mipsregs.h>
31#include <asm/ptrace.h>
32#include <linux/uaccess.h>
33
34#ifdef CONFIG_64BIT
35#define ADDIU "daddiu "
36#define INS "dins "
37#define EXT "dext "
38#else
39#define ADDIU "addiu "
40#define INS "ins "
41#define EXT "ext "
42#endif /* CONFIG_64BIT */
43
44#define SB "sb "
45#define LB "lb "
46#define LL "ll "
47#define SC "sc "
48
49#ifdef CONFIG_DEBUG_FS
50static DEFINE_PER_CPU(struct mips_r2_emulator_stats, mipsr2emustats);
51static DEFINE_PER_CPU(struct mips_r2_emulator_stats, mipsr2bdemustats);
52static DEFINE_PER_CPU(struct mips_r2br_emulator_stats, mipsr2bremustats);
53#endif
54
55extern const unsigned int fpucondbit[8];
56
57#define MIPS_R2_EMUL_TOTAL_PASS 10
58
59int mipsr2_emulation = 0;
60
61static int __init mipsr2emu_enable(char *s)
62{
63 mipsr2_emulation = 1;
64
65 pr_info("MIPS R2-to-R6 Emulator Enabled!");
66
67 return 1;
68}
69__setup("mipsr2emu", mipsr2emu_enable);
70
71/**
72 * mipsr6_emul - Emulate some frequent R2/R5/R6 instructions in delay slot
73 * for performance instead of the traditional way of using a stack trampoline
74 * which is rather slow.
75 * @regs: Process register set
76 * @ir: Instruction
77 */
78static inline int mipsr6_emul(struct pt_regs *regs, u32 ir)
79{
80 switch (MIPSInst_OPCODE(ir)) {
81 case addiu_op:
82 if (MIPSInst_RT(ir))
83 regs->regs[MIPSInst_RT(ir)] =
84 (s32)regs->regs[MIPSInst_RS(ir)] +
85 (s32)MIPSInst_SIMM(ir);
86 return 0;
87 case daddiu_op:
88 if (IS_ENABLED(CONFIG_32BIT))
89 break;
90
91 if (MIPSInst_RT(ir))
92 regs->regs[MIPSInst_RT(ir)] =
93 (s64)regs->regs[MIPSInst_RS(ir)] +
94 (s64)MIPSInst_SIMM(ir);
95 return 0;
96 case lwc1_op:
97 case swc1_op:
98 case cop1_op:
99 case cop1x_op:
100 /* FPU instructions in delay slot */
101 return -SIGFPE;
102 case spec_op:
103 switch (MIPSInst_FUNC(ir)) {
104 case or_op:
105 if (MIPSInst_RD(ir))
106 regs->regs[MIPSInst_RD(ir)] =
107 regs->regs[MIPSInst_RS(ir)] |
108 regs->regs[MIPSInst_RT(ir)];
109 return 0;
110 case sll_op:
111 if (MIPSInst_RS(ir))
112 break;
113
114 if (MIPSInst_RD(ir))
115 regs->regs[MIPSInst_RD(ir)] =
116 (s32)(((u32)regs->regs[MIPSInst_RT(ir)]) <<
117 MIPSInst_FD(ir));
118 return 0;
119 case srl_op:
120 if (MIPSInst_RS(ir))
121 break;
122
123 if (MIPSInst_RD(ir))
124 regs->regs[MIPSInst_RD(ir)] =
125 (s32)(((u32)regs->regs[MIPSInst_RT(ir)]) >>
126 MIPSInst_FD(ir));
127 return 0;
128 case addu_op:
129 if (MIPSInst_FD(ir))
130 break;
131
132 if (MIPSInst_RD(ir))
133 regs->regs[MIPSInst_RD(ir)] =
134 (s32)((u32)regs->regs[MIPSInst_RS(ir)] +
135 (u32)regs->regs[MIPSInst_RT(ir)]);
136 return 0;
137 case subu_op:
138 if (MIPSInst_FD(ir))
139 break;
140
141 if (MIPSInst_RD(ir))
142 regs->regs[MIPSInst_RD(ir)] =
143 (s32)((u32)regs->regs[MIPSInst_RS(ir)] -
144 (u32)regs->regs[MIPSInst_RT(ir)]);
145 return 0;
146 case dsll_op:
147 if (IS_ENABLED(CONFIG_32BIT) || MIPSInst_RS(ir))
148 break;
149
150 if (MIPSInst_RD(ir))
151 regs->regs[MIPSInst_RD(ir)] =
152 (s64)(((u64)regs->regs[MIPSInst_RT(ir)]) <<
153 MIPSInst_FD(ir));
154 return 0;
155 case dsrl_op:
156 if (IS_ENABLED(CONFIG_32BIT) || MIPSInst_RS(ir))
157 break;
158
159 if (MIPSInst_RD(ir))
160 regs->regs[MIPSInst_RD(ir)] =
161 (s64)(((u64)regs->regs[MIPSInst_RT(ir)]) >>
162 MIPSInst_FD(ir));
163 return 0;
164 case daddu_op:
165 if (IS_ENABLED(CONFIG_32BIT) || MIPSInst_FD(ir))
166 break;
167
168 if (MIPSInst_RD(ir))
169 regs->regs[MIPSInst_RD(ir)] =
170 (u64)regs->regs[MIPSInst_RS(ir)] +
171 (u64)regs->regs[MIPSInst_RT(ir)];
172 return 0;
173 case dsubu_op:
174 if (IS_ENABLED(CONFIG_32BIT) || MIPSInst_FD(ir))
175 break;
176
177 if (MIPSInst_RD(ir))
178 regs->regs[MIPSInst_RD(ir)] =
179 (s64)((u64)regs->regs[MIPSInst_RS(ir)] -
180 (u64)regs->regs[MIPSInst_RT(ir)]);
181 return 0;
182 }
183 break;
184 default:
185 pr_debug("No fastpath BD emulation for instruction 0x%08x (op: %02x)\n",
186 ir, MIPSInst_OPCODE(ir));
187 }
188
189 return SIGILL;
190}
191
192/**
193 * movf_func - Emulate a MOVF instruction
194 * @regs: Process register set
195 * @ir: Instruction
196 *
197 * Returns 0 since it always succeeds.
198 */
199static int movf_func(struct pt_regs *regs, u32 ir)
200{
201 u32 csr;
202 u32 cond;
203
204 csr = current->thread.fpu.fcr31;
205 cond = fpucondbit[MIPSInst_RT(ir) >> 2];
206
207 if (((csr & cond) == 0) && MIPSInst_RD(ir))
208 regs->regs[MIPSInst_RD(ir)] = regs->regs[MIPSInst_RS(ir)];
209
210 MIPS_R2_STATS(movs);
211
212 return 0;
213}
214
215/**
216 * movt_func - Emulate a MOVT instruction
217 * @regs: Process register set
218 * @ir: Instruction
219 *
220 * Returns 0 since it always succeeds.
221 */
222static int movt_func(struct pt_regs *regs, u32 ir)
223{
224 u32 csr;
225 u32 cond;
226
227 csr = current->thread.fpu.fcr31;
228 cond = fpucondbit[MIPSInst_RT(ir) >> 2];
229
230 if (((csr & cond) != 0) && MIPSInst_RD(ir))
231 regs->regs[MIPSInst_RD(ir)] = regs->regs[MIPSInst_RS(ir)];
232
233 MIPS_R2_STATS(movs);
234
235 return 0;
236}
237
238/**
239 * jr_func - Emulate a JR instruction.
240 * @pt_regs: Process register set
241 * @ir: Instruction
242 *
243 * Returns SIGILL if JR was in delay slot, SIGEMT if we
244 * can't compute the EPC, SIGSEGV if we can't access the
245 * userland instruction or 0 on success.
246 */
247static int jr_func(struct pt_regs *regs, u32 ir)
248{
249 int err;
250 unsigned long cepc, epc, nepc;
251 u32 nir;
252
253 if (delay_slot(regs))
254 return SIGILL;
255
256 /* EPC after the RI/JR instruction */
257 nepc = regs->cp0_epc;
258 /* Roll back to the reserved R2 JR instruction */
259 regs->cp0_epc -= 4;
260 epc = regs->cp0_epc;
261 err = __compute_return_epc(regs);
262
263 if (err < 0)
264 return SIGEMT;
265
266
267 /* Computed EPC */
268 cepc = regs->cp0_epc;
269
270 /* Get DS instruction */
271 err = __get_user(nir, (u32 __user *)nepc);
272 if (err)
273 return SIGSEGV;
274
275 MIPS_R2BR_STATS(jrs);
276
277 /* If nir == 0(NOP), then nothing else to do */
278 if (nir) {
279 /*
280 * Negative err means FPU instruction in BD-slot,
281 * Zero err means 'BD-slot emulation done'
282 * For anything else we go back to trampoline emulation.
283 */
284 err = mipsr6_emul(regs, ir: nir);
285 if (err > 0) {
286 regs->cp0_epc = nepc;
287 err = mips_dsemul(regs, nir, epc, cepc);
288 if (err == SIGILL)
289 err = SIGEMT;
290 MIPS_R2_STATS(dsemul);
291 }
292 }
293
294 return err;
295}
296
297/**
298 * movz_func - Emulate a MOVZ instruction
299 * @regs: Process register set
300 * @ir: Instruction
301 *
302 * Returns 0 since it always succeeds.
303 */
304static int movz_func(struct pt_regs *regs, u32 ir)
305{
306 if (((regs->regs[MIPSInst_RT(ir)]) == 0) && MIPSInst_RD(ir))
307 regs->regs[MIPSInst_RD(ir)] = regs->regs[MIPSInst_RS(ir)];
308 MIPS_R2_STATS(movs);
309
310 return 0;
311}
312
313/**
314 * movn_func - Emulate a MOVZ instruction
315 * @regs: Process register set
316 * @ir: Instruction
317 *
318 * Returns 0 since it always succeeds.
319 */
320static int movn_func(struct pt_regs *regs, u32 ir)
321{
322 if (((regs->regs[MIPSInst_RT(ir)]) != 0) && MIPSInst_RD(ir))
323 regs->regs[MIPSInst_RD(ir)] = regs->regs[MIPSInst_RS(ir)];
324 MIPS_R2_STATS(movs);
325
326 return 0;
327}
328
329/**
330 * mfhi_func - Emulate a MFHI instruction
331 * @regs: Process register set
332 * @ir: Instruction
333 *
334 * Returns 0 since it always succeeds.
335 */
336static int mfhi_func(struct pt_regs *regs, u32 ir)
337{
338 if (MIPSInst_RD(ir))
339 regs->regs[MIPSInst_RD(ir)] = regs->hi;
340
341 MIPS_R2_STATS(hilo);
342
343 return 0;
344}
345
346/**
347 * mthi_func - Emulate a MTHI instruction
348 * @regs: Process register set
349 * @ir: Instruction
350 *
351 * Returns 0 since it always succeeds.
352 */
353static int mthi_func(struct pt_regs *regs, u32 ir)
354{
355 regs->hi = regs->regs[MIPSInst_RS(ir)];
356
357 MIPS_R2_STATS(hilo);
358
359 return 0;
360}
361
362/**
363 * mflo_func - Emulate a MFLO instruction
364 * @regs: Process register set
365 * @ir: Instruction
366 *
367 * Returns 0 since it always succeeds.
368 */
369static int mflo_func(struct pt_regs *regs, u32 ir)
370{
371 if (MIPSInst_RD(ir))
372 regs->regs[MIPSInst_RD(ir)] = regs->lo;
373
374 MIPS_R2_STATS(hilo);
375
376 return 0;
377}
378
379/**
380 * mtlo_func - Emulate a MTLO instruction
381 * @regs: Process register set
382 * @ir: Instruction
383 *
384 * Returns 0 since it always succeeds.
385 */
386static int mtlo_func(struct pt_regs *regs, u32 ir)
387{
388 regs->lo = regs->regs[MIPSInst_RS(ir)];
389
390 MIPS_R2_STATS(hilo);
391
392 return 0;
393}
394
395/**
396 * mult_func - Emulate a MULT instruction
397 * @regs: Process register set
398 * @ir: Instruction
399 *
400 * Returns 0 since it always succeeds.
401 */
402static int mult_func(struct pt_regs *regs, u32 ir)
403{
404 s64 res;
405 s32 rt, rs;
406
407 rt = regs->regs[MIPSInst_RT(ir)];
408 rs = regs->regs[MIPSInst_RS(ir)];
409 res = (s64)rt * (s64)rs;
410
411 rs = res;
412 regs->lo = (s64)rs;
413 rt = res >> 32;
414 res = (s64)rt;
415 regs->hi = res;
416
417 MIPS_R2_STATS(muls);
418
419 return 0;
420}
421
422/**
423 * multu_func - Emulate a MULTU instruction
424 * @regs: Process register set
425 * @ir: Instruction
426 *
427 * Returns 0 since it always succeeds.
428 */
429static int multu_func(struct pt_regs *regs, u32 ir)
430{
431 u64 res;
432 u32 rt, rs;
433
434 rt = regs->regs[MIPSInst_RT(ir)];
435 rs = regs->regs[MIPSInst_RS(ir)];
436 res = (u64)rt * (u64)rs;
437 rt = res;
438 regs->lo = (s64)(s32)rt;
439 regs->hi = (s64)(s32)(res >> 32);
440
441 MIPS_R2_STATS(muls);
442
443 return 0;
444}
445
446/**
447 * div_func - Emulate a DIV instruction
448 * @regs: Process register set
449 * @ir: Instruction
450 *
451 * Returns 0 since it always succeeds.
452 */
453static int div_func(struct pt_regs *regs, u32 ir)
454{
455 s32 rt, rs;
456
457 rt = regs->regs[MIPSInst_RT(ir)];
458 rs = regs->regs[MIPSInst_RS(ir)];
459
460 regs->lo = (s64)(rs / rt);
461 regs->hi = (s64)(rs % rt);
462
463 MIPS_R2_STATS(divs);
464
465 return 0;
466}
467
468/**
469 * divu_func - Emulate a DIVU instruction
470 * @regs: Process register set
471 * @ir: Instruction
472 *
473 * Returns 0 since it always succeeds.
474 */
475static int divu_func(struct pt_regs *regs, u32 ir)
476{
477 u32 rt, rs;
478
479 rt = regs->regs[MIPSInst_RT(ir)];
480 rs = regs->regs[MIPSInst_RS(ir)];
481
482 regs->lo = (s64)(rs / rt);
483 regs->hi = (s64)(rs % rt);
484
485 MIPS_R2_STATS(divs);
486
487 return 0;
488}
489
490/**
491 * dmult_func - Emulate a DMULT instruction
492 * @regs: Process register set
493 * @ir: Instruction
494 *
495 * Returns 0 on success or SIGILL for 32-bit kernels.
496 */
497static int dmult_func(struct pt_regs *regs, u32 ir)
498{
499 s64 res;
500 s64 rt, rs;
501
502 if (IS_ENABLED(CONFIG_32BIT))
503 return SIGILL;
504
505 rt = regs->regs[MIPSInst_RT(ir)];
506 rs = regs->regs[MIPSInst_RS(ir)];
507 res = rt * rs;
508
509 regs->lo = res;
510 __asm__ __volatile__(
511 "dmuh %0, %1, %2\t\n"
512 : "=r"(res)
513 : "r"(rt), "r"(rs));
514
515 regs->hi = res;
516
517 MIPS_R2_STATS(muls);
518
519 return 0;
520}
521
522/**
523 * dmultu_func - Emulate a DMULTU instruction
524 * @regs: Process register set
525 * @ir: Instruction
526 *
527 * Returns 0 on success or SIGILL for 32-bit kernels.
528 */
529static int dmultu_func(struct pt_regs *regs, u32 ir)
530{
531 u64 res;
532 u64 rt, rs;
533
534 if (IS_ENABLED(CONFIG_32BIT))
535 return SIGILL;
536
537 rt = regs->regs[MIPSInst_RT(ir)];
538 rs = regs->regs[MIPSInst_RS(ir)];
539 res = rt * rs;
540
541 regs->lo = res;
542 __asm__ __volatile__(
543 "dmuhu %0, %1, %2\t\n"
544 : "=r"(res)
545 : "r"(rt), "r"(rs));
546
547 regs->hi = res;
548
549 MIPS_R2_STATS(muls);
550
551 return 0;
552}
553
554/**
555 * ddiv_func - Emulate a DDIV instruction
556 * @regs: Process register set
557 * @ir: Instruction
558 *
559 * Returns 0 on success or SIGILL for 32-bit kernels.
560 */
561static int ddiv_func(struct pt_regs *regs, u32 ir)
562{
563 s64 rt, rs;
564
565 if (IS_ENABLED(CONFIG_32BIT))
566 return SIGILL;
567
568 rt = regs->regs[MIPSInst_RT(ir)];
569 rs = regs->regs[MIPSInst_RS(ir)];
570
571 regs->lo = rs / rt;
572 regs->hi = rs % rt;
573
574 MIPS_R2_STATS(divs);
575
576 return 0;
577}
578
579/**
580 * ddivu_func - Emulate a DDIVU instruction
581 * @regs: Process register set
582 * @ir: Instruction
583 *
584 * Returns 0 on success or SIGILL for 32-bit kernels.
585 */
586static int ddivu_func(struct pt_regs *regs, u32 ir)
587{
588 u64 rt, rs;
589
590 if (IS_ENABLED(CONFIG_32BIT))
591 return SIGILL;
592
593 rt = regs->regs[MIPSInst_RT(ir)];
594 rs = regs->regs[MIPSInst_RS(ir)];
595
596 regs->lo = rs / rt;
597 regs->hi = rs % rt;
598
599 MIPS_R2_STATS(divs);
600
601 return 0;
602}
603
604/* R6 removed instructions for the SPECIAL opcode */
605static const struct r2_decoder_table spec_op_table[] = {
606 { 0xfc1ff83f, 0x00000008, jr_func },
607 { 0xfc00ffff, 0x00000018, mult_func },
608 { 0xfc00ffff, 0x00000019, multu_func },
609 { 0xfc00ffff, 0x0000001c, dmult_func },
610 { 0xfc00ffff, 0x0000001d, dmultu_func },
611 { 0xffff07ff, 0x00000010, mfhi_func },
612 { 0xfc1fffff, 0x00000011, mthi_func },
613 { 0xffff07ff, 0x00000012, mflo_func },
614 { 0xfc1fffff, 0x00000013, mtlo_func },
615 { 0xfc0307ff, 0x00000001, movf_func },
616 { 0xfc0307ff, 0x00010001, movt_func },
617 { 0xfc0007ff, 0x0000000a, movz_func },
618 { 0xfc0007ff, 0x0000000b, movn_func },
619 { 0xfc00ffff, 0x0000001a, div_func },
620 { 0xfc00ffff, 0x0000001b, divu_func },
621 { 0xfc00ffff, 0x0000001e, ddiv_func },
622 { 0xfc00ffff, 0x0000001f, ddivu_func },
623 {}
624};
625
626/**
627 * madd_func - Emulate a MADD instruction
628 * @regs: Process register set
629 * @ir: Instruction
630 *
631 * Returns 0 since it always succeeds.
632 */
633static int madd_func(struct pt_regs *regs, u32 ir)
634{
635 s64 res;
636 s32 rt, rs;
637
638 rt = regs->regs[MIPSInst_RT(ir)];
639 rs = regs->regs[MIPSInst_RS(ir)];
640 res = (s64)rt * (s64)rs;
641 rt = regs->hi;
642 rs = regs->lo;
643 res += ((((s64)rt) << 32) | (u32)rs);
644
645 rt = res;
646 regs->lo = (s64)rt;
647 rs = res >> 32;
648 regs->hi = (s64)rs;
649
650 MIPS_R2_STATS(dsps);
651
652 return 0;
653}
654
655/**
656 * maddu_func - Emulate a MADDU instruction
657 * @regs: Process register set
658 * @ir: Instruction
659 *
660 * Returns 0 since it always succeeds.
661 */
662static int maddu_func(struct pt_regs *regs, u32 ir)
663{
664 u64 res;
665 u32 rt, rs;
666
667 rt = regs->regs[MIPSInst_RT(ir)];
668 rs = regs->regs[MIPSInst_RS(ir)];
669 res = (u64)rt * (u64)rs;
670 rt = regs->hi;
671 rs = regs->lo;
672 res += ((((s64)rt) << 32) | (u32)rs);
673
674 rt = res;
675 regs->lo = (s64)(s32)rt;
676 rs = res >> 32;
677 regs->hi = (s64)(s32)rs;
678
679 MIPS_R2_STATS(dsps);
680
681 return 0;
682}
683
684/**
685 * msub_func - Emulate a MSUB instruction
686 * @regs: Process register set
687 * @ir: Instruction
688 *
689 * Returns 0 since it always succeeds.
690 */
691static int msub_func(struct pt_regs *regs, u32 ir)
692{
693 s64 res;
694 s32 rt, rs;
695
696 rt = regs->regs[MIPSInst_RT(ir)];
697 rs = regs->regs[MIPSInst_RS(ir)];
698 res = (s64)rt * (s64)rs;
699 rt = regs->hi;
700 rs = regs->lo;
701 res = ((((s64)rt) << 32) | (u32)rs) - res;
702
703 rt = res;
704 regs->lo = (s64)rt;
705 rs = res >> 32;
706 regs->hi = (s64)rs;
707
708 MIPS_R2_STATS(dsps);
709
710 return 0;
711}
712
713/**
714 * msubu_func - Emulate a MSUBU instruction
715 * @regs: Process register set
716 * @ir: Instruction
717 *
718 * Returns 0 since it always succeeds.
719 */
720static int msubu_func(struct pt_regs *regs, u32 ir)
721{
722 u64 res;
723 u32 rt, rs;
724
725 rt = regs->regs[MIPSInst_RT(ir)];
726 rs = regs->regs[MIPSInst_RS(ir)];
727 res = (u64)rt * (u64)rs;
728 rt = regs->hi;
729 rs = regs->lo;
730 res = ((((s64)rt) << 32) | (u32)rs) - res;
731
732 rt = res;
733 regs->lo = (s64)(s32)rt;
734 rs = res >> 32;
735 regs->hi = (s64)(s32)rs;
736
737 MIPS_R2_STATS(dsps);
738
739 return 0;
740}
741
742/**
743 * mul_func - Emulate a MUL instruction
744 * @regs: Process register set
745 * @ir: Instruction
746 *
747 * Returns 0 since it always succeeds.
748 */
749static int mul_func(struct pt_regs *regs, u32 ir)
750{
751 s64 res;
752 s32 rt, rs;
753
754 if (!MIPSInst_RD(ir))
755 return 0;
756 rt = regs->regs[MIPSInst_RT(ir)];
757 rs = regs->regs[MIPSInst_RS(ir)];
758 res = (s64)rt * (s64)rs;
759
760 rs = res;
761 regs->regs[MIPSInst_RD(ir)] = (s64)rs;
762
763 MIPS_R2_STATS(muls);
764
765 return 0;
766}
767
768/**
769 * clz_func - Emulate a CLZ instruction
770 * @regs: Process register set
771 * @ir: Instruction
772 *
773 * Returns 0 since it always succeeds.
774 */
775static int clz_func(struct pt_regs *regs, u32 ir)
776{
777 u32 res;
778 u32 rs;
779
780 if (!MIPSInst_RD(ir))
781 return 0;
782
783 rs = regs->regs[MIPSInst_RS(ir)];
784 __asm__ __volatile__("clz %0, %1" : "=r"(res) : "r"(rs));
785 regs->regs[MIPSInst_RD(ir)] = res;
786
787 MIPS_R2_STATS(bops);
788
789 return 0;
790}
791
792/**
793 * clo_func - Emulate a CLO instruction
794 * @regs: Process register set
795 * @ir: Instruction
796 *
797 * Returns 0 since it always succeeds.
798 */
799
800static int clo_func(struct pt_regs *regs, u32 ir)
801{
802 u32 res;
803 u32 rs;
804
805 if (!MIPSInst_RD(ir))
806 return 0;
807
808 rs = regs->regs[MIPSInst_RS(ir)];
809 __asm__ __volatile__("clo %0, %1" : "=r"(res) : "r"(rs));
810 regs->regs[MIPSInst_RD(ir)] = res;
811
812 MIPS_R2_STATS(bops);
813
814 return 0;
815}
816
817/**
818 * dclz_func - Emulate a DCLZ instruction
819 * @regs: Process register set
820 * @ir: Instruction
821 *
822 * Returns 0 since it always succeeds.
823 */
824static int dclz_func(struct pt_regs *regs, u32 ir)
825{
826 u64 res;
827 u64 rs;
828
829 if (IS_ENABLED(CONFIG_32BIT))
830 return SIGILL;
831
832 if (!MIPSInst_RD(ir))
833 return 0;
834
835 rs = regs->regs[MIPSInst_RS(ir)];
836 __asm__ __volatile__("dclz %0, %1" : "=r"(res) : "r"(rs));
837 regs->regs[MIPSInst_RD(ir)] = res;
838
839 MIPS_R2_STATS(bops);
840
841 return 0;
842}
843
844/**
845 * dclo_func - Emulate a DCLO instruction
846 * @regs: Process register set
847 * @ir: Instruction
848 *
849 * Returns 0 since it always succeeds.
850 */
851static int dclo_func(struct pt_regs *regs, u32 ir)
852{
853 u64 res;
854 u64 rs;
855
856 if (IS_ENABLED(CONFIG_32BIT))
857 return SIGILL;
858
859 if (!MIPSInst_RD(ir))
860 return 0;
861
862 rs = regs->regs[MIPSInst_RS(ir)];
863 __asm__ __volatile__("dclo %0, %1" : "=r"(res) : "r"(rs));
864 regs->regs[MIPSInst_RD(ir)] = res;
865
866 MIPS_R2_STATS(bops);
867
868 return 0;
869}
870
871/* R6 removed instructions for the SPECIAL2 opcode */
872static const struct r2_decoder_table spec2_op_table[] = {
873 { 0xfc00ffff, 0x70000000, madd_func },
874 { 0xfc00ffff, 0x70000001, maddu_func },
875 { 0xfc0007ff, 0x70000002, mul_func },
876 { 0xfc00ffff, 0x70000004, msub_func },
877 { 0xfc00ffff, 0x70000005, msubu_func },
878 { 0xfc0007ff, 0x70000020, clz_func },
879 { 0xfc0007ff, 0x70000021, clo_func },
880 { 0xfc0007ff, 0x70000024, dclz_func },
881 { 0xfc0007ff, 0x70000025, dclo_func },
882 { }
883};
884
885static inline int mipsr2_find_op_func(struct pt_regs *regs, u32 inst,
886 const struct r2_decoder_table *table)
887{
888 const struct r2_decoder_table *p;
889 int err;
890
891 for (p = table; p->func; p++) {
892 if ((inst & p->mask) == p->code) {
893 err = (p->func)(regs, inst);
894 return err;
895 }
896 }
897 return SIGILL;
898}
899
900/**
901 * mipsr2_decoder: Decode and emulate a MIPS R2 instruction
902 * @regs: Process register set
903 * @inst: Instruction to decode and emulate
904 * @fcr31: Floating Point Control and Status Register Cause bits returned
905 */
906int mipsr2_decoder(struct pt_regs *regs, u32 inst, unsigned long *fcr31)
907{
908 int err = 0;
909 unsigned long vaddr;
910 u32 nir;
911 unsigned long cpc, epc, nepc, r31, res, rs, rt;
912
913 void __user *fault_addr = NULL;
914 int pass = 0;
915
916repeat:
917 r31 = regs->regs[31];
918 epc = regs->cp0_epc;
919 err = compute_return_epc(regs);
920 if (err < 0) {
921 BUG();
922 return SIGEMT;
923 }
924 pr_debug("Emulating the 0x%08x R2 instruction @ 0x%08lx (pass=%d))\n",
925 inst, epc, pass);
926
927 switch (MIPSInst_OPCODE(inst)) {
928 case spec_op:
929 err = mipsr2_find_op_func(regs, inst, table: spec_op_table);
930 if (err < 0) {
931 /* FPU instruction under JR */
932 regs->cp0_cause |= CAUSEF_BD;
933 goto fpu_emul;
934 }
935 break;
936 case spec2_op:
937 err = mipsr2_find_op_func(regs, inst, table: spec2_op_table);
938 break;
939 case bcond_op:
940 rt = MIPSInst_RT(inst);
941 rs = MIPSInst_RS(inst);
942 switch (rt) {
943 case tgei_op:
944 if ((long)regs->regs[rs] >= MIPSInst_SIMM(inst))
945 do_trap_or_bp(regs, 0, 0, "TGEI");
946
947 MIPS_R2_STATS(traps);
948
949 break;
950 case tgeiu_op:
951 if (regs->regs[rs] >= MIPSInst_UIMM(inst))
952 do_trap_or_bp(regs, 0, 0, "TGEIU");
953
954 MIPS_R2_STATS(traps);
955
956 break;
957 case tlti_op:
958 if ((long)regs->regs[rs] < MIPSInst_SIMM(inst))
959 do_trap_or_bp(regs, 0, 0, "TLTI");
960
961 MIPS_R2_STATS(traps);
962
963 break;
964 case tltiu_op:
965 if (regs->regs[rs] < MIPSInst_UIMM(inst))
966 do_trap_or_bp(regs, 0, 0, "TLTIU");
967
968 MIPS_R2_STATS(traps);
969
970 break;
971 case teqi_op:
972 if (regs->regs[rs] == MIPSInst_SIMM(inst))
973 do_trap_or_bp(regs, 0, 0, "TEQI");
974
975 MIPS_R2_STATS(traps);
976
977 break;
978 case tnei_op:
979 if (regs->regs[rs] != MIPSInst_SIMM(inst))
980 do_trap_or_bp(regs, 0, 0, "TNEI");
981
982 MIPS_R2_STATS(traps);
983
984 break;
985 case bltzl_op:
986 case bgezl_op:
987 case bltzall_op:
988 case bgezall_op:
989 if (delay_slot(regs)) {
990 err = SIGILL;
991 break;
992 }
993 regs->regs[31] = r31;
994 regs->cp0_epc = epc;
995 err = __compute_return_epc(regs);
996 if (err < 0)
997 return SIGEMT;
998 if (err != BRANCH_LIKELY_TAKEN)
999 break;
1000 cpc = regs->cp0_epc;
1001 nepc = epc + 4;
1002 err = __get_user(nir, (u32 __user *)nepc);
1003 if (err) {
1004 err = SIGSEGV;
1005 break;
1006 }
1007 /*
1008 * This will probably be optimized away when
1009 * CONFIG_DEBUG_FS is not enabled
1010 */
1011 switch (rt) {
1012 case bltzl_op:
1013 MIPS_R2BR_STATS(bltzl);
1014 break;
1015 case bgezl_op:
1016 MIPS_R2BR_STATS(bgezl);
1017 break;
1018 case bltzall_op:
1019 MIPS_R2BR_STATS(bltzall);
1020 break;
1021 case bgezall_op:
1022 MIPS_R2BR_STATS(bgezall);
1023 break;
1024 }
1025
1026 switch (MIPSInst_OPCODE(nir)) {
1027 case cop1_op:
1028 case cop1x_op:
1029 case lwc1_op:
1030 case swc1_op:
1031 regs->cp0_cause |= CAUSEF_BD;
1032 goto fpu_emul;
1033 }
1034 if (nir) {
1035 err = mipsr6_emul(regs, ir: nir);
1036 if (err > 0) {
1037 err = mips_dsemul(regs, nir, epc, cpc);
1038 if (err == SIGILL)
1039 err = SIGEMT;
1040 MIPS_R2_STATS(dsemul);
1041 }
1042 }
1043 break;
1044 case bltzal_op:
1045 case bgezal_op:
1046 if (delay_slot(regs)) {
1047 err = SIGILL;
1048 break;
1049 }
1050 regs->regs[31] = r31;
1051 regs->cp0_epc = epc;
1052 err = __compute_return_epc(regs);
1053 if (err < 0)
1054 return SIGEMT;
1055 cpc = regs->cp0_epc;
1056 nepc = epc + 4;
1057 err = __get_user(nir, (u32 __user *)nepc);
1058 if (err) {
1059 err = SIGSEGV;
1060 break;
1061 }
1062 /*
1063 * This will probably be optimized away when
1064 * CONFIG_DEBUG_FS is not enabled
1065 */
1066 switch (rt) {
1067 case bltzal_op:
1068 MIPS_R2BR_STATS(bltzal);
1069 break;
1070 case bgezal_op:
1071 MIPS_R2BR_STATS(bgezal);
1072 break;
1073 }
1074
1075 switch (MIPSInst_OPCODE(nir)) {
1076 case cop1_op:
1077 case cop1x_op:
1078 case lwc1_op:
1079 case swc1_op:
1080 regs->cp0_cause |= CAUSEF_BD;
1081 goto fpu_emul;
1082 }
1083 if (nir) {
1084 err = mipsr6_emul(regs, ir: nir);
1085 if (err > 0) {
1086 err = mips_dsemul(regs, nir, epc, cpc);
1087 if (err == SIGILL)
1088 err = SIGEMT;
1089 MIPS_R2_STATS(dsemul);
1090 }
1091 }
1092 break;
1093 default:
1094 regs->regs[31] = r31;
1095 regs->cp0_epc = epc;
1096 err = SIGILL;
1097 break;
1098 }
1099 break;
1100
1101 case blezl_op:
1102 case bgtzl_op:
1103 /*
1104 * For BLEZL and BGTZL, rt field must be set to 0. If this
1105 * is not the case, this may be an encoding of a MIPS R6
1106 * instruction, so return to CPU execution if this occurs
1107 */
1108 if (MIPSInst_RT(inst)) {
1109 err = SIGILL;
1110 break;
1111 }
1112 fallthrough;
1113 case beql_op:
1114 case bnel_op:
1115 if (delay_slot(regs)) {
1116 err = SIGILL;
1117 break;
1118 }
1119 regs->regs[31] = r31;
1120 regs->cp0_epc = epc;
1121 err = __compute_return_epc(regs);
1122 if (err < 0)
1123 return SIGEMT;
1124 if (err != BRANCH_LIKELY_TAKEN)
1125 break;
1126 cpc = regs->cp0_epc;
1127 nepc = epc + 4;
1128 err = __get_user(nir, (u32 __user *)nepc);
1129 if (err) {
1130 err = SIGSEGV;
1131 break;
1132 }
1133 /*
1134 * This will probably be optimized away when
1135 * CONFIG_DEBUG_FS is not enabled
1136 */
1137 switch (MIPSInst_OPCODE(inst)) {
1138 case beql_op:
1139 MIPS_R2BR_STATS(beql);
1140 break;
1141 case bnel_op:
1142 MIPS_R2BR_STATS(bnel);
1143 break;
1144 case blezl_op:
1145 MIPS_R2BR_STATS(blezl);
1146 break;
1147 case bgtzl_op:
1148 MIPS_R2BR_STATS(bgtzl);
1149 break;
1150 }
1151
1152 switch (MIPSInst_OPCODE(nir)) {
1153 case cop1_op:
1154 case cop1x_op:
1155 case lwc1_op:
1156 case swc1_op:
1157 regs->cp0_cause |= CAUSEF_BD;
1158 goto fpu_emul;
1159 }
1160 if (nir) {
1161 err = mipsr6_emul(regs, ir: nir);
1162 if (err > 0) {
1163 err = mips_dsemul(regs, nir, epc, cpc);
1164 if (err == SIGILL)
1165 err = SIGEMT;
1166 MIPS_R2_STATS(dsemul);
1167 }
1168 }
1169 break;
1170 case lwc1_op:
1171 case swc1_op:
1172 case cop1_op:
1173 case cop1x_op:
1174fpu_emul:
1175 regs->regs[31] = r31;
1176 regs->cp0_epc = epc;
1177
1178 err = fpu_emulator_cop1Handler(regs, &current->thread.fpu, 0,
1179 &fault_addr);
1180
1181 /*
1182 * We can't allow the emulated instruction to leave any
1183 * enabled Cause bits set in $fcr31.
1184 */
1185 *fcr31 = res = mask_fcr31_x(current->thread.fpu.fcr31);
1186 current->thread.fpu.fcr31 &= ~res;
1187
1188 /*
1189 * this is a tricky issue - lose_fpu() uses LL/SC atomics
1190 * if FPU is owned and effectively cancels user level LL/SC.
1191 * So, it could be logical to don't restore FPU ownership here.
1192 * But the sequence of multiple FPU instructions is much much
1193 * more often than LL-FPU-SC and I prefer loop here until
1194 * next scheduler cycle cancels FPU ownership
1195 */
1196 own_fpu(1); /* Restore FPU state. */
1197
1198 if (err)
1199 current->thread.cp0_baduaddr = (unsigned long)fault_addr;
1200
1201 MIPS_R2_STATS(fpus);
1202
1203 break;
1204
1205 case lwl_op:
1206 rt = regs->regs[MIPSInst_RT(inst)];
1207 vaddr = regs->regs[MIPSInst_RS(inst)] + MIPSInst_SIMM(inst);
1208 if (!access_ok((void __user *)vaddr, 4)) {
1209 current->thread.cp0_baduaddr = vaddr;
1210 err = SIGSEGV;
1211 break;
1212 }
1213 __asm__ __volatile__(
1214 " .set push\n"
1215 " .set reorder\n"
1216#ifdef CONFIG_CPU_LITTLE_ENDIAN
1217 "1:" LB "%1, 0(%2)\n"
1218 INS "%0, %1, 24, 8\n"
1219 " andi %1, %2, 0x3\n"
1220 " beq $0, %1, 9f\n"
1221 ADDIU "%2, %2, -1\n"
1222 "2:" LB "%1, 0(%2)\n"
1223 INS "%0, %1, 16, 8\n"
1224 " andi %1, %2, 0x3\n"
1225 " beq $0, %1, 9f\n"
1226 ADDIU "%2, %2, -1\n"
1227 "3:" LB "%1, 0(%2)\n"
1228 INS "%0, %1, 8, 8\n"
1229 " andi %1, %2, 0x3\n"
1230 " beq $0, %1, 9f\n"
1231 ADDIU "%2, %2, -1\n"
1232 "4:" LB "%1, 0(%2)\n"
1233 INS "%0, %1, 0, 8\n"
1234#else /* !CONFIG_CPU_LITTLE_ENDIAN */
1235 "1:" LB "%1, 0(%2)\n"
1236 INS "%0, %1, 24, 8\n"
1237 ADDIU "%2, %2, 1\n"
1238 " andi %1, %2, 0x3\n"
1239 " beq $0, %1, 9f\n"
1240 "2:" LB "%1, 0(%2)\n"
1241 INS "%0, %1, 16, 8\n"
1242 ADDIU "%2, %2, 1\n"
1243 " andi %1, %2, 0x3\n"
1244 " beq $0, %1, 9f\n"
1245 "3:" LB "%1, 0(%2)\n"
1246 INS "%0, %1, 8, 8\n"
1247 ADDIU "%2, %2, 1\n"
1248 " andi %1, %2, 0x3\n"
1249 " beq $0, %1, 9f\n"
1250 "4:" LB "%1, 0(%2)\n"
1251 INS "%0, %1, 0, 8\n"
1252#endif /* CONFIG_CPU_LITTLE_ENDIAN */
1253 "9: sll %0, %0, 0\n"
1254 "10:\n"
1255 " .insn\n"
1256 " .section .fixup,\"ax\"\n"
1257 "8: li %3,%4\n"
1258 " j 10b\n"
1259 " .previous\n"
1260 " .section __ex_table,\"a\"\n"
1261 STR(PTR_WD) " 1b,8b\n"
1262 STR(PTR_WD) " 2b,8b\n"
1263 STR(PTR_WD) " 3b,8b\n"
1264 STR(PTR_WD) " 4b,8b\n"
1265 " .previous\n"
1266 " .set pop\n"
1267 : "+&r"(rt), "=&r"(rs),
1268 "+&r"(vaddr), "+&r"(err)
1269 : "i"(SIGSEGV));
1270
1271 if (MIPSInst_RT(inst) && !err)
1272 regs->regs[MIPSInst_RT(inst)] = rt;
1273
1274 MIPS_R2_STATS(loads);
1275
1276 break;
1277
1278 case lwr_op:
1279 rt = regs->regs[MIPSInst_RT(inst)];
1280 vaddr = regs->regs[MIPSInst_RS(inst)] + MIPSInst_SIMM(inst);
1281 if (!access_ok((void __user *)vaddr, 4)) {
1282 current->thread.cp0_baduaddr = vaddr;
1283 err = SIGSEGV;
1284 break;
1285 }
1286 __asm__ __volatile__(
1287 " .set push\n"
1288 " .set reorder\n"
1289#ifdef CONFIG_CPU_LITTLE_ENDIAN
1290 "1:" LB "%1, 0(%2)\n"
1291 INS "%0, %1, 0, 8\n"
1292 ADDIU "%2, %2, 1\n"
1293 " andi %1, %2, 0x3\n"
1294 " beq $0, %1, 9f\n"
1295 "2:" LB "%1, 0(%2)\n"
1296 INS "%0, %1, 8, 8\n"
1297 ADDIU "%2, %2, 1\n"
1298 " andi %1, %2, 0x3\n"
1299 " beq $0, %1, 9f\n"
1300 "3:" LB "%1, 0(%2)\n"
1301 INS "%0, %1, 16, 8\n"
1302 ADDIU "%2, %2, 1\n"
1303 " andi %1, %2, 0x3\n"
1304 " beq $0, %1, 9f\n"
1305 "4:" LB "%1, 0(%2)\n"
1306 INS "%0, %1, 24, 8\n"
1307 " sll %0, %0, 0\n"
1308#else /* !CONFIG_CPU_LITTLE_ENDIAN */
1309 "1:" LB "%1, 0(%2)\n"
1310 INS "%0, %1, 0, 8\n"
1311 " andi %1, %2, 0x3\n"
1312 " beq $0, %1, 9f\n"
1313 ADDIU "%2, %2, -1\n"
1314 "2:" LB "%1, 0(%2)\n"
1315 INS "%0, %1, 8, 8\n"
1316 " andi %1, %2, 0x3\n"
1317 " beq $0, %1, 9f\n"
1318 ADDIU "%2, %2, -1\n"
1319 "3:" LB "%1, 0(%2)\n"
1320 INS "%0, %1, 16, 8\n"
1321 " andi %1, %2, 0x3\n"
1322 " beq $0, %1, 9f\n"
1323 ADDIU "%2, %2, -1\n"
1324 "4:" LB "%1, 0(%2)\n"
1325 INS "%0, %1, 24, 8\n"
1326 " sll %0, %0, 0\n"
1327#endif /* CONFIG_CPU_LITTLE_ENDIAN */
1328 "9:\n"
1329 "10:\n"
1330 " .insn\n"
1331 " .section .fixup,\"ax\"\n"
1332 "8: li %3,%4\n"
1333 " j 10b\n"
1334 " .previous\n"
1335 " .section __ex_table,\"a\"\n"
1336 STR(PTR_WD) " 1b,8b\n"
1337 STR(PTR_WD) " 2b,8b\n"
1338 STR(PTR_WD) " 3b,8b\n"
1339 STR(PTR_WD) " 4b,8b\n"
1340 " .previous\n"
1341 " .set pop\n"
1342 : "+&r"(rt), "=&r"(rs),
1343 "+&r"(vaddr), "+&r"(err)
1344 : "i"(SIGSEGV));
1345 if (MIPSInst_RT(inst) && !err)
1346 regs->regs[MIPSInst_RT(inst)] = rt;
1347
1348 MIPS_R2_STATS(loads);
1349
1350 break;
1351
1352 case swl_op:
1353 rt = regs->regs[MIPSInst_RT(inst)];
1354 vaddr = regs->regs[MIPSInst_RS(inst)] + MIPSInst_SIMM(inst);
1355 if (!access_ok((void __user *)vaddr, 4)) {
1356 current->thread.cp0_baduaddr = vaddr;
1357 err = SIGSEGV;
1358 break;
1359 }
1360 __asm__ __volatile__(
1361 " .set push\n"
1362 " .set reorder\n"
1363#ifdef CONFIG_CPU_LITTLE_ENDIAN
1364 EXT "%1, %0, 24, 8\n"
1365 "1:" SB "%1, 0(%2)\n"
1366 " andi %1, %2, 0x3\n"
1367 " beq $0, %1, 9f\n"
1368 ADDIU "%2, %2, -1\n"
1369 EXT "%1, %0, 16, 8\n"
1370 "2:" SB "%1, 0(%2)\n"
1371 " andi %1, %2, 0x3\n"
1372 " beq $0, %1, 9f\n"
1373 ADDIU "%2, %2, -1\n"
1374 EXT "%1, %0, 8, 8\n"
1375 "3:" SB "%1, 0(%2)\n"
1376 " andi %1, %2, 0x3\n"
1377 " beq $0, %1, 9f\n"
1378 ADDIU "%2, %2, -1\n"
1379 EXT "%1, %0, 0, 8\n"
1380 "4:" SB "%1, 0(%2)\n"
1381#else /* !CONFIG_CPU_LITTLE_ENDIAN */
1382 EXT "%1, %0, 24, 8\n"
1383 "1:" SB "%1, 0(%2)\n"
1384 ADDIU "%2, %2, 1\n"
1385 " andi %1, %2, 0x3\n"
1386 " beq $0, %1, 9f\n"
1387 EXT "%1, %0, 16, 8\n"
1388 "2:" SB "%1, 0(%2)\n"
1389 ADDIU "%2, %2, 1\n"
1390 " andi %1, %2, 0x3\n"
1391 " beq $0, %1, 9f\n"
1392 EXT "%1, %0, 8, 8\n"
1393 "3:" SB "%1, 0(%2)\n"
1394 ADDIU "%2, %2, 1\n"
1395 " andi %1, %2, 0x3\n"
1396 " beq $0, %1, 9f\n"
1397 EXT "%1, %0, 0, 8\n"
1398 "4:" SB "%1, 0(%2)\n"
1399#endif /* CONFIG_CPU_LITTLE_ENDIAN */
1400 "9:\n"
1401 " .insn\n"
1402 " .section .fixup,\"ax\"\n"
1403 "8: li %3,%4\n"
1404 " j 9b\n"
1405 " .previous\n"
1406 " .section __ex_table,\"a\"\n"
1407 STR(PTR_WD) " 1b,8b\n"
1408 STR(PTR_WD) " 2b,8b\n"
1409 STR(PTR_WD) " 3b,8b\n"
1410 STR(PTR_WD) " 4b,8b\n"
1411 " .previous\n"
1412 " .set pop\n"
1413 : "+&r"(rt), "=&r"(rs),
1414 "+&r"(vaddr), "+&r"(err)
1415 : "i"(SIGSEGV)
1416 : "memory");
1417
1418 MIPS_R2_STATS(stores);
1419
1420 break;
1421
1422 case swr_op:
1423 rt = regs->regs[MIPSInst_RT(inst)];
1424 vaddr = regs->regs[MIPSInst_RS(inst)] + MIPSInst_SIMM(inst);
1425 if (!access_ok((void __user *)vaddr, 4)) {
1426 current->thread.cp0_baduaddr = vaddr;
1427 err = SIGSEGV;
1428 break;
1429 }
1430 __asm__ __volatile__(
1431 " .set push\n"
1432 " .set reorder\n"
1433#ifdef CONFIG_CPU_LITTLE_ENDIAN
1434 EXT "%1, %0, 0, 8\n"
1435 "1:" SB "%1, 0(%2)\n"
1436 ADDIU "%2, %2, 1\n"
1437 " andi %1, %2, 0x3\n"
1438 " beq $0, %1, 9f\n"
1439 EXT "%1, %0, 8, 8\n"
1440 "2:" SB "%1, 0(%2)\n"
1441 ADDIU "%2, %2, 1\n"
1442 " andi %1, %2, 0x3\n"
1443 " beq $0, %1, 9f\n"
1444 EXT "%1, %0, 16, 8\n"
1445 "3:" SB "%1, 0(%2)\n"
1446 ADDIU "%2, %2, 1\n"
1447 " andi %1, %2, 0x3\n"
1448 " beq $0, %1, 9f\n"
1449 EXT "%1, %0, 24, 8\n"
1450 "4:" SB "%1, 0(%2)\n"
1451#else /* !CONFIG_CPU_LITTLE_ENDIAN */
1452 EXT "%1, %0, 0, 8\n"
1453 "1:" SB "%1, 0(%2)\n"
1454 " andi %1, %2, 0x3\n"
1455 " beq $0, %1, 9f\n"
1456 ADDIU "%2, %2, -1\n"
1457 EXT "%1, %0, 8, 8\n"
1458 "2:" SB "%1, 0(%2)\n"
1459 " andi %1, %2, 0x3\n"
1460 " beq $0, %1, 9f\n"
1461 ADDIU "%2, %2, -1\n"
1462 EXT "%1, %0, 16, 8\n"
1463 "3:" SB "%1, 0(%2)\n"
1464 " andi %1, %2, 0x3\n"
1465 " beq $0, %1, 9f\n"
1466 ADDIU "%2, %2, -1\n"
1467 EXT "%1, %0, 24, 8\n"
1468 "4:" SB "%1, 0(%2)\n"
1469#endif /* CONFIG_CPU_LITTLE_ENDIAN */
1470 "9:\n"
1471 " .insn\n"
1472 " .section .fixup,\"ax\"\n"
1473 "8: li %3,%4\n"
1474 " j 9b\n"
1475 " .previous\n"
1476 " .section __ex_table,\"a\"\n"
1477 STR(PTR_WD) " 1b,8b\n"
1478 STR(PTR_WD) " 2b,8b\n"
1479 STR(PTR_WD) " 3b,8b\n"
1480 STR(PTR_WD) " 4b,8b\n"
1481 " .previous\n"
1482 " .set pop\n"
1483 : "+&r"(rt), "=&r"(rs),
1484 "+&r"(vaddr), "+&r"(err)
1485 : "i"(SIGSEGV)
1486 : "memory");
1487
1488 MIPS_R2_STATS(stores);
1489
1490 break;
1491
1492 case ldl_op:
1493 if (IS_ENABLED(CONFIG_32BIT)) {
1494 err = SIGILL;
1495 break;
1496 }
1497
1498 rt = regs->regs[MIPSInst_RT(inst)];
1499 vaddr = regs->regs[MIPSInst_RS(inst)] + MIPSInst_SIMM(inst);
1500 if (!access_ok((void __user *)vaddr, 8)) {
1501 current->thread.cp0_baduaddr = vaddr;
1502 err = SIGSEGV;
1503 break;
1504 }
1505 __asm__ __volatile__(
1506 " .set push\n"
1507 " .set reorder\n"
1508#ifdef CONFIG_CPU_LITTLE_ENDIAN
1509 "1: lb %1, 0(%2)\n"
1510 " dinsu %0, %1, 56, 8\n"
1511 " andi %1, %2, 0x7\n"
1512 " beq $0, %1, 9f\n"
1513 " daddiu %2, %2, -1\n"
1514 "2: lb %1, 0(%2)\n"
1515 " dinsu %0, %1, 48, 8\n"
1516 " andi %1, %2, 0x7\n"
1517 " beq $0, %1, 9f\n"
1518 " daddiu %2, %2, -1\n"
1519 "3: lb %1, 0(%2)\n"
1520 " dinsu %0, %1, 40, 8\n"
1521 " andi %1, %2, 0x7\n"
1522 " beq $0, %1, 9f\n"
1523 " daddiu %2, %2, -1\n"
1524 "4: lb %1, 0(%2)\n"
1525 " dinsu %0, %1, 32, 8\n"
1526 " andi %1, %2, 0x7\n"
1527 " beq $0, %1, 9f\n"
1528 " daddiu %2, %2, -1\n"
1529 "5: lb %1, 0(%2)\n"
1530 " dins %0, %1, 24, 8\n"
1531 " andi %1, %2, 0x7\n"
1532 " beq $0, %1, 9f\n"
1533 " daddiu %2, %2, -1\n"
1534 "6: lb %1, 0(%2)\n"
1535 " dins %0, %1, 16, 8\n"
1536 " andi %1, %2, 0x7\n"
1537 " beq $0, %1, 9f\n"
1538 " daddiu %2, %2, -1\n"
1539 "7: lb %1, 0(%2)\n"
1540 " dins %0, %1, 8, 8\n"
1541 " andi %1, %2, 0x7\n"
1542 " beq $0, %1, 9f\n"
1543 " daddiu %2, %2, -1\n"
1544 "0: lb %1, 0(%2)\n"
1545 " dins %0, %1, 0, 8\n"
1546#else /* !CONFIG_CPU_LITTLE_ENDIAN */
1547 "1: lb %1, 0(%2)\n"
1548 " dinsu %0, %1, 56, 8\n"
1549 " daddiu %2, %2, 1\n"
1550 " andi %1, %2, 0x7\n"
1551 " beq $0, %1, 9f\n"
1552 "2: lb %1, 0(%2)\n"
1553 " dinsu %0, %1, 48, 8\n"
1554 " daddiu %2, %2, 1\n"
1555 " andi %1, %2, 0x7\n"
1556 " beq $0, %1, 9f\n"
1557 "3: lb %1, 0(%2)\n"
1558 " dinsu %0, %1, 40, 8\n"
1559 " daddiu %2, %2, 1\n"
1560 " andi %1, %2, 0x7\n"
1561 " beq $0, %1, 9f\n"
1562 "4: lb %1, 0(%2)\n"
1563 " dinsu %0, %1, 32, 8\n"
1564 " daddiu %2, %2, 1\n"
1565 " andi %1, %2, 0x7\n"
1566 " beq $0, %1, 9f\n"
1567 "5: lb %1, 0(%2)\n"
1568 " dins %0, %1, 24, 8\n"
1569 " daddiu %2, %2, 1\n"
1570 " andi %1, %2, 0x7\n"
1571 " beq $0, %1, 9f\n"
1572 "6: lb %1, 0(%2)\n"
1573 " dins %0, %1, 16, 8\n"
1574 " daddiu %2, %2, 1\n"
1575 " andi %1, %2, 0x7\n"
1576 " beq $0, %1, 9f\n"
1577 "7: lb %1, 0(%2)\n"
1578 " dins %0, %1, 8, 8\n"
1579 " daddiu %2, %2, 1\n"
1580 " andi %1, %2, 0x7\n"
1581 " beq $0, %1, 9f\n"
1582 "0: lb %1, 0(%2)\n"
1583 " dins %0, %1, 0, 8\n"
1584#endif /* CONFIG_CPU_LITTLE_ENDIAN */
1585 "9:\n"
1586 " .insn\n"
1587 " .section .fixup,\"ax\"\n"
1588 "8: li %3,%4\n"
1589 " j 9b\n"
1590 " .previous\n"
1591 " .section __ex_table,\"a\"\n"
1592 STR(PTR_WD) " 1b,8b\n"
1593 STR(PTR_WD) " 2b,8b\n"
1594 STR(PTR_WD) " 3b,8b\n"
1595 STR(PTR_WD) " 4b,8b\n"
1596 STR(PTR_WD) " 5b,8b\n"
1597 STR(PTR_WD) " 6b,8b\n"
1598 STR(PTR_WD) " 7b,8b\n"
1599 STR(PTR_WD) " 0b,8b\n"
1600 " .previous\n"
1601 " .set pop\n"
1602 : "+&r"(rt), "=&r"(rs),
1603 "+&r"(vaddr), "+&r"(err)
1604 : "i"(SIGSEGV));
1605 if (MIPSInst_RT(inst) && !err)
1606 regs->regs[MIPSInst_RT(inst)] = rt;
1607
1608 MIPS_R2_STATS(loads);
1609 break;
1610
1611 case ldr_op:
1612 if (IS_ENABLED(CONFIG_32BIT)) {
1613 err = SIGILL;
1614 break;
1615 }
1616
1617 rt = regs->regs[MIPSInst_RT(inst)];
1618 vaddr = regs->regs[MIPSInst_RS(inst)] + MIPSInst_SIMM(inst);
1619 if (!access_ok((void __user *)vaddr, 8)) {
1620 current->thread.cp0_baduaddr = vaddr;
1621 err = SIGSEGV;
1622 break;
1623 }
1624 __asm__ __volatile__(
1625 " .set push\n"
1626 " .set reorder\n"
1627#ifdef CONFIG_CPU_LITTLE_ENDIAN
1628 "1: lb %1, 0(%2)\n"
1629 " dins %0, %1, 0, 8\n"
1630 " daddiu %2, %2, 1\n"
1631 " andi %1, %2, 0x7\n"
1632 " beq $0, %1, 9f\n"
1633 "2: lb %1, 0(%2)\n"
1634 " dins %0, %1, 8, 8\n"
1635 " daddiu %2, %2, 1\n"
1636 " andi %1, %2, 0x7\n"
1637 " beq $0, %1, 9f\n"
1638 "3: lb %1, 0(%2)\n"
1639 " dins %0, %1, 16, 8\n"
1640 " daddiu %2, %2, 1\n"
1641 " andi %1, %2, 0x7\n"
1642 " beq $0, %1, 9f\n"
1643 "4: lb %1, 0(%2)\n"
1644 " dins %0, %1, 24, 8\n"
1645 " daddiu %2, %2, 1\n"
1646 " andi %1, %2, 0x7\n"
1647 " beq $0, %1, 9f\n"
1648 "5: lb %1, 0(%2)\n"
1649 " dinsu %0, %1, 32, 8\n"
1650 " daddiu %2, %2, 1\n"
1651 " andi %1, %2, 0x7\n"
1652 " beq $0, %1, 9f\n"
1653 "6: lb %1, 0(%2)\n"
1654 " dinsu %0, %1, 40, 8\n"
1655 " daddiu %2, %2, 1\n"
1656 " andi %1, %2, 0x7\n"
1657 " beq $0, %1, 9f\n"
1658 "7: lb %1, 0(%2)\n"
1659 " dinsu %0, %1, 48, 8\n"
1660 " daddiu %2, %2, 1\n"
1661 " andi %1, %2, 0x7\n"
1662 " beq $0, %1, 9f\n"
1663 "0: lb %1, 0(%2)\n"
1664 " dinsu %0, %1, 56, 8\n"
1665#else /* !CONFIG_CPU_LITTLE_ENDIAN */
1666 "1: lb %1, 0(%2)\n"
1667 " dins %0, %1, 0, 8\n"
1668 " andi %1, %2, 0x7\n"
1669 " beq $0, %1, 9f\n"
1670 " daddiu %2, %2, -1\n"
1671 "2: lb %1, 0(%2)\n"
1672 " dins %0, %1, 8, 8\n"
1673 " andi %1, %2, 0x7\n"
1674 " beq $0, %1, 9f\n"
1675 " daddiu %2, %2, -1\n"
1676 "3: lb %1, 0(%2)\n"
1677 " dins %0, %1, 16, 8\n"
1678 " andi %1, %2, 0x7\n"
1679 " beq $0, %1, 9f\n"
1680 " daddiu %2, %2, -1\n"
1681 "4: lb %1, 0(%2)\n"
1682 " dins %0, %1, 24, 8\n"
1683 " andi %1, %2, 0x7\n"
1684 " beq $0, %1, 9f\n"
1685 " daddiu %2, %2, -1\n"
1686 "5: lb %1, 0(%2)\n"
1687 " dinsu %0, %1, 32, 8\n"
1688 " andi %1, %2, 0x7\n"
1689 " beq $0, %1, 9f\n"
1690 " daddiu %2, %2, -1\n"
1691 "6: lb %1, 0(%2)\n"
1692 " dinsu %0, %1, 40, 8\n"
1693 " andi %1, %2, 0x7\n"
1694 " beq $0, %1, 9f\n"
1695 " daddiu %2, %2, -1\n"
1696 "7: lb %1, 0(%2)\n"
1697 " dinsu %0, %1, 48, 8\n"
1698 " andi %1, %2, 0x7\n"
1699 " beq $0, %1, 9f\n"
1700 " daddiu %2, %2, -1\n"
1701 "0: lb %1, 0(%2)\n"
1702 " dinsu %0, %1, 56, 8\n"
1703#endif /* CONFIG_CPU_LITTLE_ENDIAN */
1704 "9:\n"
1705 " .insn\n"
1706 " .section .fixup,\"ax\"\n"
1707 "8: li %3,%4\n"
1708 " j 9b\n"
1709 " .previous\n"
1710 " .section __ex_table,\"a\"\n"
1711 STR(PTR_WD) " 1b,8b\n"
1712 STR(PTR_WD) " 2b,8b\n"
1713 STR(PTR_WD) " 3b,8b\n"
1714 STR(PTR_WD) " 4b,8b\n"
1715 STR(PTR_WD) " 5b,8b\n"
1716 STR(PTR_WD) " 6b,8b\n"
1717 STR(PTR_WD) " 7b,8b\n"
1718 STR(PTR_WD) " 0b,8b\n"
1719 " .previous\n"
1720 " .set pop\n"
1721 : "+&r"(rt), "=&r"(rs),
1722 "+&r"(vaddr), "+&r"(err)
1723 : "i"(SIGSEGV));
1724 if (MIPSInst_RT(inst) && !err)
1725 regs->regs[MIPSInst_RT(inst)] = rt;
1726
1727 MIPS_R2_STATS(loads);
1728 break;
1729
1730 case sdl_op:
1731 if (IS_ENABLED(CONFIG_32BIT)) {
1732 err = SIGILL;
1733 break;
1734 }
1735
1736 rt = regs->regs[MIPSInst_RT(inst)];
1737 vaddr = regs->regs[MIPSInst_RS(inst)] + MIPSInst_SIMM(inst);
1738 if (!access_ok((void __user *)vaddr, 8)) {
1739 current->thread.cp0_baduaddr = vaddr;
1740 err = SIGSEGV;
1741 break;
1742 }
1743 __asm__ __volatile__(
1744 " .set push\n"
1745 " .set reorder\n"
1746#ifdef CONFIG_CPU_LITTLE_ENDIAN
1747 " dextu %1, %0, 56, 8\n"
1748 "1: sb %1, 0(%2)\n"
1749 " andi %1, %2, 0x7\n"
1750 " beq $0, %1, 9f\n"
1751 " daddiu %2, %2, -1\n"
1752 " dextu %1, %0, 48, 8\n"
1753 "2: sb %1, 0(%2)\n"
1754 " andi %1, %2, 0x7\n"
1755 " beq $0, %1, 9f\n"
1756 " daddiu %2, %2, -1\n"
1757 " dextu %1, %0, 40, 8\n"
1758 "3: sb %1, 0(%2)\n"
1759 " andi %1, %2, 0x7\n"
1760 " beq $0, %1, 9f\n"
1761 " daddiu %2, %2, -1\n"
1762 " dextu %1, %0, 32, 8\n"
1763 "4: sb %1, 0(%2)\n"
1764 " andi %1, %2, 0x7\n"
1765 " beq $0, %1, 9f\n"
1766 " daddiu %2, %2, -1\n"
1767 " dext %1, %0, 24, 8\n"
1768 "5: sb %1, 0(%2)\n"
1769 " andi %1, %2, 0x7\n"
1770 " beq $0, %1, 9f\n"
1771 " daddiu %2, %2, -1\n"
1772 " dext %1, %0, 16, 8\n"
1773 "6: sb %1, 0(%2)\n"
1774 " andi %1, %2, 0x7\n"
1775 " beq $0, %1, 9f\n"
1776 " daddiu %2, %2, -1\n"
1777 " dext %1, %0, 8, 8\n"
1778 "7: sb %1, 0(%2)\n"
1779 " andi %1, %2, 0x7\n"
1780 " beq $0, %1, 9f\n"
1781 " daddiu %2, %2, -1\n"
1782 " dext %1, %0, 0, 8\n"
1783 "0: sb %1, 0(%2)\n"
1784#else /* !CONFIG_CPU_LITTLE_ENDIAN */
1785 " dextu %1, %0, 56, 8\n"
1786 "1: sb %1, 0(%2)\n"
1787 " daddiu %2, %2, 1\n"
1788 " andi %1, %2, 0x7\n"
1789 " beq $0, %1, 9f\n"
1790 " dextu %1, %0, 48, 8\n"
1791 "2: sb %1, 0(%2)\n"
1792 " daddiu %2, %2, 1\n"
1793 " andi %1, %2, 0x7\n"
1794 " beq $0, %1, 9f\n"
1795 " dextu %1, %0, 40, 8\n"
1796 "3: sb %1, 0(%2)\n"
1797 " daddiu %2, %2, 1\n"
1798 " andi %1, %2, 0x7\n"
1799 " beq $0, %1, 9f\n"
1800 " dextu %1, %0, 32, 8\n"
1801 "4: sb %1, 0(%2)\n"
1802 " daddiu %2, %2, 1\n"
1803 " andi %1, %2, 0x7\n"
1804 " beq $0, %1, 9f\n"
1805 " dext %1, %0, 24, 8\n"
1806 "5: sb %1, 0(%2)\n"
1807 " daddiu %2, %2, 1\n"
1808 " andi %1, %2, 0x7\n"
1809 " beq $0, %1, 9f\n"
1810 " dext %1, %0, 16, 8\n"
1811 "6: sb %1, 0(%2)\n"
1812 " daddiu %2, %2, 1\n"
1813 " andi %1, %2, 0x7\n"
1814 " beq $0, %1, 9f\n"
1815 " dext %1, %0, 8, 8\n"
1816 "7: sb %1, 0(%2)\n"
1817 " daddiu %2, %2, 1\n"
1818 " andi %1, %2, 0x7\n"
1819 " beq $0, %1, 9f\n"
1820 " dext %1, %0, 0, 8\n"
1821 "0: sb %1, 0(%2)\n"
1822#endif /* CONFIG_CPU_LITTLE_ENDIAN */
1823 "9:\n"
1824 " .insn\n"
1825 " .section .fixup,\"ax\"\n"
1826 "8: li %3,%4\n"
1827 " j 9b\n"
1828 " .previous\n"
1829 " .section __ex_table,\"a\"\n"
1830 STR(PTR_WD) " 1b,8b\n"
1831 STR(PTR_WD) " 2b,8b\n"
1832 STR(PTR_WD) " 3b,8b\n"
1833 STR(PTR_WD) " 4b,8b\n"
1834 STR(PTR_WD) " 5b,8b\n"
1835 STR(PTR_WD) " 6b,8b\n"
1836 STR(PTR_WD) " 7b,8b\n"
1837 STR(PTR_WD) " 0b,8b\n"
1838 " .previous\n"
1839 " .set pop\n"
1840 : "+&r"(rt), "=&r"(rs),
1841 "+&r"(vaddr), "+&r"(err)
1842 : "i"(SIGSEGV)
1843 : "memory");
1844
1845 MIPS_R2_STATS(stores);
1846 break;
1847
1848 case sdr_op:
1849 if (IS_ENABLED(CONFIG_32BIT)) {
1850 err = SIGILL;
1851 break;
1852 }
1853
1854 rt = regs->regs[MIPSInst_RT(inst)];
1855 vaddr = regs->regs[MIPSInst_RS(inst)] + MIPSInst_SIMM(inst);
1856 if (!access_ok((void __user *)vaddr, 8)) {
1857 current->thread.cp0_baduaddr = vaddr;
1858 err = SIGSEGV;
1859 break;
1860 }
1861 __asm__ __volatile__(
1862 " .set push\n"
1863 " .set reorder\n"
1864#ifdef CONFIG_CPU_LITTLE_ENDIAN
1865 " dext %1, %0, 0, 8\n"
1866 "1: sb %1, 0(%2)\n"
1867 " daddiu %2, %2, 1\n"
1868 " andi %1, %2, 0x7\n"
1869 " beq $0, %1, 9f\n"
1870 " dext %1, %0, 8, 8\n"
1871 "2: sb %1, 0(%2)\n"
1872 " daddiu %2, %2, 1\n"
1873 " andi %1, %2, 0x7\n"
1874 " beq $0, %1, 9f\n"
1875 " dext %1, %0, 16, 8\n"
1876 "3: sb %1, 0(%2)\n"
1877 " daddiu %2, %2, 1\n"
1878 " andi %1, %2, 0x7\n"
1879 " beq $0, %1, 9f\n"
1880 " dext %1, %0, 24, 8\n"
1881 "4: sb %1, 0(%2)\n"
1882 " daddiu %2, %2, 1\n"
1883 " andi %1, %2, 0x7\n"
1884 " beq $0, %1, 9f\n"
1885 " dextu %1, %0, 32, 8\n"
1886 "5: sb %1, 0(%2)\n"
1887 " daddiu %2, %2, 1\n"
1888 " andi %1, %2, 0x7\n"
1889 " beq $0, %1, 9f\n"
1890 " dextu %1, %0, 40, 8\n"
1891 "6: sb %1, 0(%2)\n"
1892 " daddiu %2, %2, 1\n"
1893 " andi %1, %2, 0x7\n"
1894 " beq $0, %1, 9f\n"
1895 " dextu %1, %0, 48, 8\n"
1896 "7: sb %1, 0(%2)\n"
1897 " daddiu %2, %2, 1\n"
1898 " andi %1, %2, 0x7\n"
1899 " beq $0, %1, 9f\n"
1900 " dextu %1, %0, 56, 8\n"
1901 "0: sb %1, 0(%2)\n"
1902#else /* !CONFIG_CPU_LITTLE_ENDIAN */
1903 " dext %1, %0, 0, 8\n"
1904 "1: sb %1, 0(%2)\n"
1905 " andi %1, %2, 0x7\n"
1906 " beq $0, %1, 9f\n"
1907 " daddiu %2, %2, -1\n"
1908 " dext %1, %0, 8, 8\n"
1909 "2: sb %1, 0(%2)\n"
1910 " andi %1, %2, 0x7\n"
1911 " beq $0, %1, 9f\n"
1912 " daddiu %2, %2, -1\n"
1913 " dext %1, %0, 16, 8\n"
1914 "3: sb %1, 0(%2)\n"
1915 " andi %1, %2, 0x7\n"
1916 " beq $0, %1, 9f\n"
1917 " daddiu %2, %2, -1\n"
1918 " dext %1, %0, 24, 8\n"
1919 "4: sb %1, 0(%2)\n"
1920 " andi %1, %2, 0x7\n"
1921 " beq $0, %1, 9f\n"
1922 " daddiu %2, %2, -1\n"
1923 " dextu %1, %0, 32, 8\n"
1924 "5: sb %1, 0(%2)\n"
1925 " andi %1, %2, 0x7\n"
1926 " beq $0, %1, 9f\n"
1927 " daddiu %2, %2, -1\n"
1928 " dextu %1, %0, 40, 8\n"
1929 "6: sb %1, 0(%2)\n"
1930 " andi %1, %2, 0x7\n"
1931 " beq $0, %1, 9f\n"
1932 " daddiu %2, %2, -1\n"
1933 " dextu %1, %0, 48, 8\n"
1934 "7: sb %1, 0(%2)\n"
1935 " andi %1, %2, 0x7\n"
1936 " beq $0, %1, 9f\n"
1937 " daddiu %2, %2, -1\n"
1938 " dextu %1, %0, 56, 8\n"
1939 "0: sb %1, 0(%2)\n"
1940#endif /* CONFIG_CPU_LITTLE_ENDIAN */
1941 "9:\n"
1942 " .insn\n"
1943 " .section .fixup,\"ax\"\n"
1944 "8: li %3,%4\n"
1945 " j 9b\n"
1946 " .previous\n"
1947 " .section __ex_table,\"a\"\n"
1948 STR(PTR_WD) " 1b,8b\n"
1949 STR(PTR_WD) " 2b,8b\n"
1950 STR(PTR_WD) " 3b,8b\n"
1951 STR(PTR_WD) " 4b,8b\n"
1952 STR(PTR_WD) " 5b,8b\n"
1953 STR(PTR_WD) " 6b,8b\n"
1954 STR(PTR_WD) " 7b,8b\n"
1955 STR(PTR_WD) " 0b,8b\n"
1956 " .previous\n"
1957 " .set pop\n"
1958 : "+&r"(rt), "=&r"(rs),
1959 "+&r"(vaddr), "+&r"(err)
1960 : "i"(SIGSEGV)
1961 : "memory");
1962
1963 MIPS_R2_STATS(stores);
1964
1965 break;
1966 case ll_op:
1967 vaddr = regs->regs[MIPSInst_RS(inst)] + MIPSInst_SIMM(inst);
1968 if (vaddr & 0x3) {
1969 current->thread.cp0_baduaddr = vaddr;
1970 err = SIGBUS;
1971 break;
1972 }
1973 if (!access_ok((void __user *)vaddr, 4)) {
1974 current->thread.cp0_baduaddr = vaddr;
1975 err = SIGBUS;
1976 break;
1977 }
1978
1979 if (!cpu_has_rw_llb) {
1980 /*
1981 * An LL/SC block can't be safely emulated without
1982 * a Config5/LLB availability. So it's probably time to
1983 * kill our process before things get any worse. This is
1984 * because Config5/LLB allows us to use ERETNC so that
1985 * the LLAddr/LLB bit is not cleared when we return from
1986 * an exception. MIPS R2 LL/SC instructions trap with an
1987 * RI exception so once we emulate them here, we return
1988 * back to userland with ERETNC. That preserves the
1989 * LLAddr/LLB so the subsequent SC instruction will
1990 * succeed preserving the atomic semantics of the LL/SC
1991 * block. Without that, there is no safe way to emulate
1992 * an LL/SC block in MIPSR2 userland.
1993 */
1994 pr_err("Can't emulate MIPSR2 LL/SC without Config5/LLB\n");
1995 err = SIGKILL;
1996 break;
1997 }
1998
1999 __asm__ __volatile__(
2000 "1:\n"
2001 "ll %0, 0(%2)\n"
2002 "2:\n"
2003 ".insn\n"
2004 ".section .fixup,\"ax\"\n"
2005 "3:\n"
2006 "li %1, %3\n"
2007 "j 2b\n"
2008 ".previous\n"
2009 ".section __ex_table,\"a\"\n"
2010 STR(PTR_WD) " 1b,3b\n"
2011 ".previous\n"
2012 : "=&r"(res), "+&r"(err)
2013 : "r"(vaddr), "i"(SIGSEGV)
2014 : "memory");
2015
2016 if (MIPSInst_RT(inst) && !err)
2017 regs->regs[MIPSInst_RT(inst)] = res;
2018 MIPS_R2_STATS(llsc);
2019
2020 break;
2021
2022 case sc_op:
2023 vaddr = regs->regs[MIPSInst_RS(inst)] + MIPSInst_SIMM(inst);
2024 if (vaddr & 0x3) {
2025 current->thread.cp0_baduaddr = vaddr;
2026 err = SIGBUS;
2027 break;
2028 }
2029 if (!access_ok((void __user *)vaddr, 4)) {
2030 current->thread.cp0_baduaddr = vaddr;
2031 err = SIGBUS;
2032 break;
2033 }
2034
2035 if (!cpu_has_rw_llb) {
2036 /*
2037 * An LL/SC block can't be safely emulated without
2038 * a Config5/LLB availability. So it's probably time to
2039 * kill our process before things get any worse. This is
2040 * because Config5/LLB allows us to use ERETNC so that
2041 * the LLAddr/LLB bit is not cleared when we return from
2042 * an exception. MIPS R2 LL/SC instructions trap with an
2043 * RI exception so once we emulate them here, we return
2044 * back to userland with ERETNC. That preserves the
2045 * LLAddr/LLB so the subsequent SC instruction will
2046 * succeed preserving the atomic semantics of the LL/SC
2047 * block. Without that, there is no safe way to emulate
2048 * an LL/SC block in MIPSR2 userland.
2049 */
2050 pr_err("Can't emulate MIPSR2 LL/SC without Config5/LLB\n");
2051 err = SIGKILL;
2052 break;
2053 }
2054
2055 res = regs->regs[MIPSInst_RT(inst)];
2056
2057 __asm__ __volatile__(
2058 "1:\n"
2059 "sc %0, 0(%2)\n"
2060 "2:\n"
2061 ".insn\n"
2062 ".section .fixup,\"ax\"\n"
2063 "3:\n"
2064 "li %1, %3\n"
2065 "j 2b\n"
2066 ".previous\n"
2067 ".section __ex_table,\"a\"\n"
2068 STR(PTR_WD) " 1b,3b\n"
2069 ".previous\n"
2070 : "+&r"(res), "+&r"(err)
2071 : "r"(vaddr), "i"(SIGSEGV));
2072
2073 if (MIPSInst_RT(inst) && !err)
2074 regs->regs[MIPSInst_RT(inst)] = res;
2075
2076 MIPS_R2_STATS(llsc);
2077
2078 break;
2079
2080 case lld_op:
2081 if (IS_ENABLED(CONFIG_32BIT)) {
2082 err = SIGILL;
2083 break;
2084 }
2085
2086 vaddr = regs->regs[MIPSInst_RS(inst)] + MIPSInst_SIMM(inst);
2087 if (vaddr & 0x7) {
2088 current->thread.cp0_baduaddr = vaddr;
2089 err = SIGBUS;
2090 break;
2091 }
2092 if (!access_ok((void __user *)vaddr, 8)) {
2093 current->thread.cp0_baduaddr = vaddr;
2094 err = SIGBUS;
2095 break;
2096 }
2097
2098 if (!cpu_has_rw_llb) {
2099 /*
2100 * An LL/SC block can't be safely emulated without
2101 * a Config5/LLB availability. So it's probably time to
2102 * kill our process before things get any worse. This is
2103 * because Config5/LLB allows us to use ERETNC so that
2104 * the LLAddr/LLB bit is not cleared when we return from
2105 * an exception. MIPS R2 LL/SC instructions trap with an
2106 * RI exception so once we emulate them here, we return
2107 * back to userland with ERETNC. That preserves the
2108 * LLAddr/LLB so the subsequent SC instruction will
2109 * succeed preserving the atomic semantics of the LL/SC
2110 * block. Without that, there is no safe way to emulate
2111 * an LL/SC block in MIPSR2 userland.
2112 */
2113 pr_err("Can't emulate MIPSR2 LL/SC without Config5/LLB\n");
2114 err = SIGKILL;
2115 break;
2116 }
2117
2118 __asm__ __volatile__(
2119 "1:\n"
2120 "lld %0, 0(%2)\n"
2121 "2:\n"
2122 ".insn\n"
2123 ".section .fixup,\"ax\"\n"
2124 "3:\n"
2125 "li %1, %3\n"
2126 "j 2b\n"
2127 ".previous\n"
2128 ".section __ex_table,\"a\"\n"
2129 STR(PTR_WD) " 1b,3b\n"
2130 ".previous\n"
2131 : "=&r"(res), "+&r"(err)
2132 : "r"(vaddr), "i"(SIGSEGV)
2133 : "memory");
2134 if (MIPSInst_RT(inst) && !err)
2135 regs->regs[MIPSInst_RT(inst)] = res;
2136
2137 MIPS_R2_STATS(llsc);
2138
2139 break;
2140
2141 case scd_op:
2142 if (IS_ENABLED(CONFIG_32BIT)) {
2143 err = SIGILL;
2144 break;
2145 }
2146
2147 vaddr = regs->regs[MIPSInst_RS(inst)] + MIPSInst_SIMM(inst);
2148 if (vaddr & 0x7) {
2149 current->thread.cp0_baduaddr = vaddr;
2150 err = SIGBUS;
2151 break;
2152 }
2153 if (!access_ok((void __user *)vaddr, 8)) {
2154 current->thread.cp0_baduaddr = vaddr;
2155 err = SIGBUS;
2156 break;
2157 }
2158
2159 if (!cpu_has_rw_llb) {
2160 /*
2161 * An LL/SC block can't be safely emulated without
2162 * a Config5/LLB availability. So it's probably time to
2163 * kill our process before things get any worse. This is
2164 * because Config5/LLB allows us to use ERETNC so that
2165 * the LLAddr/LLB bit is not cleared when we return from
2166 * an exception. MIPS R2 LL/SC instructions trap with an
2167 * RI exception so once we emulate them here, we return
2168 * back to userland with ERETNC. That preserves the
2169 * LLAddr/LLB so the subsequent SC instruction will
2170 * succeed preserving the atomic semantics of the LL/SC
2171 * block. Without that, there is no safe way to emulate
2172 * an LL/SC block in MIPSR2 userland.
2173 */
2174 pr_err("Can't emulate MIPSR2 LL/SC without Config5/LLB\n");
2175 err = SIGKILL;
2176 break;
2177 }
2178
2179 res = regs->regs[MIPSInst_RT(inst)];
2180
2181 __asm__ __volatile__(
2182 "1:\n"
2183 "scd %0, 0(%2)\n"
2184 "2:\n"
2185 ".insn\n"
2186 ".section .fixup,\"ax\"\n"
2187 "3:\n"
2188 "li %1, %3\n"
2189 "j 2b\n"
2190 ".previous\n"
2191 ".section __ex_table,\"a\"\n"
2192 STR(PTR_WD) " 1b,3b\n"
2193 ".previous\n"
2194 : "+&r"(res), "+&r"(err)
2195 : "r"(vaddr), "i"(SIGSEGV));
2196
2197 if (MIPSInst_RT(inst) && !err)
2198 regs->regs[MIPSInst_RT(inst)] = res;
2199
2200 MIPS_R2_STATS(llsc);
2201
2202 break;
2203 case pref_op:
2204 /* skip it */
2205 break;
2206 default:
2207 err = SIGILL;
2208 }
2209
2210 /*
2211 * Let's not return to userland just yet. It's costly and
2212 * it's likely we have more R2 instructions to emulate
2213 */
2214 if (!err && (pass++ < MIPS_R2_EMUL_TOTAL_PASS)) {
2215 regs->cp0_cause &= ~CAUSEF_BD;
2216 err = get_user(inst, (u32 __user *)regs->cp0_epc);
2217 if (!err)
2218 goto repeat;
2219
2220 if (err < 0)
2221 err = SIGSEGV;
2222 }
2223
2224 if (err && (err != SIGEMT)) {
2225 regs->regs[31] = r31;
2226 regs->cp0_epc = epc;
2227 }
2228
2229 /* Likely a MIPS R6 compatible instruction */
2230 if (pass && (err == SIGILL))
2231 err = 0;
2232
2233 return err;
2234}
2235
2236#ifdef CONFIG_DEBUG_FS
2237
2238static int mipsr2_emul_show(struct seq_file *s, void *unused)
2239{
2240
2241 seq_printf(m: s, fmt: "Instruction\tTotal\tBDslot\n------------------------------\n");
2242 seq_printf(m: s, fmt: "movs\t\t%ld\t%ld\n",
2243 (unsigned long)__this_cpu_read(mipsr2emustats.movs),
2244 (unsigned long)__this_cpu_read(mipsr2bdemustats.movs));
2245 seq_printf(m: s, fmt: "hilo\t\t%ld\t%ld\n",
2246 (unsigned long)__this_cpu_read(mipsr2emustats.hilo),
2247 (unsigned long)__this_cpu_read(mipsr2bdemustats.hilo));
2248 seq_printf(m: s, fmt: "muls\t\t%ld\t%ld\n",
2249 (unsigned long)__this_cpu_read(mipsr2emustats.muls),
2250 (unsigned long)__this_cpu_read(mipsr2bdemustats.muls));
2251 seq_printf(m: s, fmt: "divs\t\t%ld\t%ld\n",
2252 (unsigned long)__this_cpu_read(mipsr2emustats.divs),
2253 (unsigned long)__this_cpu_read(mipsr2bdemustats.divs));
2254 seq_printf(m: s, fmt: "dsps\t\t%ld\t%ld\n",
2255 (unsigned long)__this_cpu_read(mipsr2emustats.dsps),
2256 (unsigned long)__this_cpu_read(mipsr2bdemustats.dsps));
2257 seq_printf(m: s, fmt: "bops\t\t%ld\t%ld\n",
2258 (unsigned long)__this_cpu_read(mipsr2emustats.bops),
2259 (unsigned long)__this_cpu_read(mipsr2bdemustats.bops));
2260 seq_printf(m: s, fmt: "traps\t\t%ld\t%ld\n",
2261 (unsigned long)__this_cpu_read(mipsr2emustats.traps),
2262 (unsigned long)__this_cpu_read(mipsr2bdemustats.traps));
2263 seq_printf(m: s, fmt: "fpus\t\t%ld\t%ld\n",
2264 (unsigned long)__this_cpu_read(mipsr2emustats.fpus),
2265 (unsigned long)__this_cpu_read(mipsr2bdemustats.fpus));
2266 seq_printf(m: s, fmt: "loads\t\t%ld\t%ld\n",
2267 (unsigned long)__this_cpu_read(mipsr2emustats.loads),
2268 (unsigned long)__this_cpu_read(mipsr2bdemustats.loads));
2269 seq_printf(m: s, fmt: "stores\t\t%ld\t%ld\n",
2270 (unsigned long)__this_cpu_read(mipsr2emustats.stores),
2271 (unsigned long)__this_cpu_read(mipsr2bdemustats.stores));
2272 seq_printf(m: s, fmt: "llsc\t\t%ld\t%ld\n",
2273 (unsigned long)__this_cpu_read(mipsr2emustats.llsc),
2274 (unsigned long)__this_cpu_read(mipsr2bdemustats.llsc));
2275 seq_printf(m: s, fmt: "dsemul\t\t%ld\t%ld\n",
2276 (unsigned long)__this_cpu_read(mipsr2emustats.dsemul),
2277 (unsigned long)__this_cpu_read(mipsr2bdemustats.dsemul));
2278 seq_printf(m: s, fmt: "jr\t\t%ld\n",
2279 (unsigned long)__this_cpu_read(mipsr2bremustats.jrs));
2280 seq_printf(m: s, fmt: "bltzl\t\t%ld\n",
2281 (unsigned long)__this_cpu_read(mipsr2bremustats.bltzl));
2282 seq_printf(m: s, fmt: "bgezl\t\t%ld\n",
2283 (unsigned long)__this_cpu_read(mipsr2bremustats.bgezl));
2284 seq_printf(m: s, fmt: "bltzll\t\t%ld\n",
2285 (unsigned long)__this_cpu_read(mipsr2bremustats.bltzll));
2286 seq_printf(m: s, fmt: "bgezll\t\t%ld\n",
2287 (unsigned long)__this_cpu_read(mipsr2bremustats.bgezll));
2288 seq_printf(m: s, fmt: "bltzal\t\t%ld\n",
2289 (unsigned long)__this_cpu_read(mipsr2bremustats.bltzal));
2290 seq_printf(m: s, fmt: "bgezal\t\t%ld\n",
2291 (unsigned long)__this_cpu_read(mipsr2bremustats.bgezal));
2292 seq_printf(m: s, fmt: "beql\t\t%ld\n",
2293 (unsigned long)__this_cpu_read(mipsr2bremustats.beql));
2294 seq_printf(m: s, fmt: "bnel\t\t%ld\n",
2295 (unsigned long)__this_cpu_read(mipsr2bremustats.bnel));
2296 seq_printf(m: s, fmt: "blezl\t\t%ld\n",
2297 (unsigned long)__this_cpu_read(mipsr2bremustats.blezl));
2298 seq_printf(m: s, fmt: "bgtzl\t\t%ld\n",
2299 (unsigned long)__this_cpu_read(mipsr2bremustats.bgtzl));
2300
2301 return 0;
2302}
2303
2304static int mipsr2_clear_show(struct seq_file *s, void *unused)
2305{
2306 mipsr2_emul_show(s, unused);
2307
2308 __this_cpu_write((mipsr2emustats).movs, 0);
2309 __this_cpu_write((mipsr2bdemustats).movs, 0);
2310 __this_cpu_write((mipsr2emustats).hilo, 0);
2311 __this_cpu_write((mipsr2bdemustats).hilo, 0);
2312 __this_cpu_write((mipsr2emustats).muls, 0);
2313 __this_cpu_write((mipsr2bdemustats).muls, 0);
2314 __this_cpu_write((mipsr2emustats).divs, 0);
2315 __this_cpu_write((mipsr2bdemustats).divs, 0);
2316 __this_cpu_write((mipsr2emustats).dsps, 0);
2317 __this_cpu_write((mipsr2bdemustats).dsps, 0);
2318 __this_cpu_write((mipsr2emustats).bops, 0);
2319 __this_cpu_write((mipsr2bdemustats).bops, 0);
2320 __this_cpu_write((mipsr2emustats).traps, 0);
2321 __this_cpu_write((mipsr2bdemustats).traps, 0);
2322 __this_cpu_write((mipsr2emustats).fpus, 0);
2323 __this_cpu_write((mipsr2bdemustats).fpus, 0);
2324 __this_cpu_write((mipsr2emustats).loads, 0);
2325 __this_cpu_write((mipsr2bdemustats).loads, 0);
2326 __this_cpu_write((mipsr2emustats).stores, 0);
2327 __this_cpu_write((mipsr2bdemustats).stores, 0);
2328 __this_cpu_write((mipsr2emustats).llsc, 0);
2329 __this_cpu_write((mipsr2bdemustats).llsc, 0);
2330 __this_cpu_write((mipsr2emustats).dsemul, 0);
2331 __this_cpu_write((mipsr2bdemustats).dsemul, 0);
2332 __this_cpu_write((mipsr2bremustats).jrs, 0);
2333 __this_cpu_write((mipsr2bremustats).bltzl, 0);
2334 __this_cpu_write((mipsr2bremustats).bgezl, 0);
2335 __this_cpu_write((mipsr2bremustats).bltzll, 0);
2336 __this_cpu_write((mipsr2bremustats).bgezll, 0);
2337 __this_cpu_write((mipsr2bremustats).bltzall, 0);
2338 __this_cpu_write((mipsr2bremustats).bgezall, 0);
2339 __this_cpu_write((mipsr2bremustats).bltzal, 0);
2340 __this_cpu_write((mipsr2bremustats).bgezal, 0);
2341 __this_cpu_write((mipsr2bremustats).beql, 0);
2342 __this_cpu_write((mipsr2bremustats).bnel, 0);
2343 __this_cpu_write((mipsr2bremustats).blezl, 0);
2344 __this_cpu_write((mipsr2bremustats).bgtzl, 0);
2345
2346 return 0;
2347}
2348
2349DEFINE_SHOW_ATTRIBUTE(mipsr2_emul);
2350DEFINE_SHOW_ATTRIBUTE(mipsr2_clear);
2351
2352static int __init mipsr2_init_debugfs(void)
2353{
2354 debugfs_create_file("r2_emul_stats", S_IRUGO, mips_debugfs_dir, NULL,
2355 &mipsr2_emul_fops);
2356 debugfs_create_file("r2_emul_stats_clear", S_IRUGO, mips_debugfs_dir,
2357 NULL, &mipsr2_clear_fops);
2358 return 0;
2359}
2360
2361device_initcall(mipsr2_init_debugfs);
2362
2363#endif /* CONFIG_DEBUG_FS */
2364

source code of linux/arch/mips/kernel/mips-r2-to-r6-emul.c