1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * 'traps.c' handles hardware traps and faults after we have saved some
4 * state in 'entry.S'.
5 *
6 * SuperH version: Copyright (C) 1999 Niibe Yutaka
7 * Copyright (C) 2000 Philipp Rumpf
8 * Copyright (C) 2000 David Howells
9 * Copyright (C) 2002 - 2010 Paul Mundt
10 */
11 #include <linux/kernel.h>
12 #include <linux/ptrace.h>
13 #include <linux/hardirq.h>
14 #include <linux/init.h>
15 #include <linux/spinlock.h>
16 #include <linux/kallsyms.h>
17 #include <linux/io.h>
18 #include <linux/bug.h>
19 #include <linux/debug_locks.h>
20 #include <linux/kdebug.h>
21 #include <linux/limits.h>
22 #include <linux/sysfs.h>
23 #include <linux/uaccess.h>
24 #include <linux/perf_event.h>
25 #include <linux/sched/task_stack.h>
26
27 #include <asm/alignment.h>
28 #include <asm/fpu.h>
29 #include <asm/kprobes.h>
30 #include <asm/setup.h>
31 #include <asm/traps.h>
32 #include <asm/bl_bit.h>
33
34 #ifdef CONFIG_CPU_SH2
35 # define TRAP_RESERVED_INST 4
36 # define TRAP_ILLEGAL_SLOT_INST 6
37 # define TRAP_ADDRESS_ERROR 9
38 # ifdef CONFIG_CPU_SH2A
39 # define TRAP_UBC 12
40 # define TRAP_FPU_ERROR 13
41 # define TRAP_DIVZERO_ERROR 17
42 # define TRAP_DIVOVF_ERROR 18
43 # endif
44 #else
45 #define TRAP_RESERVED_INST 12
46 #define TRAP_ILLEGAL_SLOT_INST 13
47 #endif
48
49 static inline void sign_extend(unsigned int count, unsigned char *dst)
50 {
51 #ifdef __LITTLE_ENDIAN__
52 if ((count == 1) && dst[0] & 0x80) {
53 dst[1] = 0xff;
54 dst[2] = 0xff;
55 dst[3] = 0xff;
56 }
57 if ((count == 2) && dst[1] & 0x80) {
58 dst[2] = 0xff;
59 dst[3] = 0xff;
60 }
61 #else
62 if ((count == 1) && dst[3] & 0x80) {
63 dst[2] = 0xff;
64 dst[1] = 0xff;
65 dst[0] = 0xff;
66 }
67 if ((count == 2) && dst[2] & 0x80) {
68 dst[1] = 0xff;
69 dst[0] = 0xff;
70 }
71 #endif
72 }
73
74 static struct mem_access user_mem_access = {
75 copy_from_user,
76 copy_to_user,
77 };
78
79 static unsigned long copy_from_kernel_wrapper(void *dst, const void __user *src,
80 unsigned long cnt)
81 {
82 return copy_from_kernel_nofault(dst, (const void __force *)src, cnt);
83 }
84
85 static unsigned long copy_to_kernel_wrapper(void __user *dst, const void *src,
86 unsigned long cnt)
87 {
88 return copy_to_kernel_nofault((void __force *)dst, src, cnt);
89 }
90
91 static struct mem_access kernel_mem_access = {
92 copy_from_kernel_wrapper,
93 copy_to_kernel_wrapper,
94 };
95
96 /*
97 * handle an instruction that does an unaligned memory access by emulating the
98 * desired behaviour
99 * - note that PC _may not_ point to the faulting instruction
100 * (if that instruction is in a branch delay slot)
101 * - return 0 if emulation okay, -EFAULT on existential error
102 */
103 static int handle_unaligned_ins(insn_size_t instruction, struct pt_regs *regs,
104 struct mem_access *ma)
105 {
106 int ret, index, count;
107 unsigned long *rm, *rn;
108 unsigned char *src, *dst;
109 unsigned char __user *srcu, *dstu;
110
111 index = (instruction>>8)&15; /* 0x0F00 */
112 rn = ®s->regs[index];
113
114 index = (instruction>>4)&15; /* 0x00F0 */
115 rm = ®s->regs[index];
116
117 count = 1<<(instruction&3);
118
119 switch (count) {
120 case 1: inc_unaligned_byte_access(); break;
121 case 2: inc_unaligned_word_access(); break;
122 case 4: inc_unaligned_dword_access(); break;
123 case 8: inc_unaligned_multi_access(); break;
124 }
125
126 ret = -EFAULT;
127 switch (instruction>>12) {
128 case 0: /* mov.[bwl] to/from memory via r0+rn */
129 if (instruction & 8) {
130 /* from memory */
131 srcu = (unsigned char __user *)*rm;
132 srcu += regs->regs[0];
133 dst = (unsigned char *)rn;
134 *(unsigned long *)dst = 0;
135
136 #if !defined(__LITTLE_ENDIAN__)
137 dst += 4-count;
138 #endif
139 if (ma->from(dst, srcu, count))
140 goto fetch_fault;
141
142 sign_extend(count, dst);
143 } else {
144 /* to memory */
145 src = (unsigned char *)rm;
146 #if !defined(__LITTLE_ENDIAN__)
147 src += 4-count;
148 #endif
149 dstu = (unsigned char __user *)*rn;
150 dstu += regs->regs[0];
151
152 if (ma->to(dstu, src, count))
153 goto fetch_fault;
154 }
155 ret = 0;
156 break;
157
158 case 1: /* mov.l Rm,@(disp,Rn) */
159 src = (unsigned char*) rm;
160 dstu = (unsigned char __user *)*rn;
161 dstu += (instruction&0x000F)<<2;
162
163 if (ma->to(dstu, src, 4))
164 goto fetch_fault;
165 ret = 0;
166 break;
167
168 case 2: /* mov.[bwl] to memory, possibly with pre-decrement */
169 if (instruction & 4)
170 *rn -= count;
171 src = (unsigned char*) rm;
172 dstu = (unsigned char __user *)*rn;
173 #if !defined(__LITTLE_ENDIAN__)
174 src += 4-count;
175 #endif
176 if (ma->to(dstu, src, count))
177 goto fetch_fault;
178 ret = 0;
179 break;
180
181 case 5: /* mov.l @(disp,Rm),Rn */
182 srcu = (unsigned char __user *)*rm;
183 srcu += (instruction & 0x000F) << 2;
184 dst = (unsigned char *)rn;
185 *(unsigned long *)dst = 0;
186
187 if (ma->from(dst, srcu, 4))
188 goto fetch_fault;
189 ret = 0;
190 break;
191
192 case 6: /* mov.[bwl] from memory, possibly with post-increment */
193 srcu = (unsigned char __user *)*rm;
194 if (instruction & 4)
195 *rm += count;
196 dst = (unsigned char*) rn;
197 *(unsigned long*)dst = 0;
198
199 #if !defined(__LITTLE_ENDIAN__)
200 dst += 4-count;
201 #endif
202 if (ma->from(dst, srcu, count))
203 goto fetch_fault;
204 sign_extend(count, dst);
205 ret = 0;
206 break;
207
208 case 8:
209 switch ((instruction&0xFF00)>>8) {
210 case 0x81: /* mov.w R0,@(disp,Rn) */
211 src = (unsigned char *) ®s->regs[0];
212 #if !defined(__LITTLE_ENDIAN__)
213 src += 2;
214 #endif
215 dstu = (unsigned char __user *)*rm; /* called Rn in the spec */
216 dstu += (instruction & 0x000F) << 1;
217
218 if (ma->to(dstu, src, 2))
219 goto fetch_fault;
220 ret = 0;
221 break;
222
223 case 0x85: /* mov.w @(disp,Rm),R0 */
224 srcu = (unsigned char __user *)*rm;
225 srcu += (instruction & 0x000F) << 1;
226 dst = (unsigned char *) ®s->regs[0];
227 *(unsigned long *)dst = 0;
228
229 #if !defined(__LITTLE_ENDIAN__)
230 dst += 2;
231 #endif
232 if (ma->from(dst, srcu, 2))
233 goto fetch_fault;
234 sign_extend(2, dst);
235 ret = 0;
236 break;
237 }
238 break;
239
240 case 9: /* mov.w @(disp,PC),Rn */
241 srcu = (unsigned char __user *)regs->pc;
242 srcu += 4;
243 srcu += (instruction & 0x00FF) << 1;
244 dst = (unsigned char *)rn;
245 *(unsigned long *)dst = 0;
246
247 #if !defined(__LITTLE_ENDIAN__)
248 dst += 2;
249 #endif
250
251 if (ma->from(dst, srcu, 2))
252 goto fetch_fault;
253 sign_extend(2, dst);
254 ret = 0;
255 break;
256
257 case 0xd: /* mov.l @(disp,PC),Rn */
258 srcu = (unsigned char __user *)(regs->pc & ~0x3);
259 srcu += 4;
260 srcu += (instruction & 0x00FF) << 2;
261 dst = (unsigned char *)rn;
262 *(unsigned long *)dst = 0;
263
264 if (ma->from(dst, srcu, 4))
265 goto fetch_fault;
266 ret = 0;
267 break;
268 }
269 return ret;
270
271 fetch_fault:
272 /* Argh. Address not only misaligned but also non-existent.
273 * Raise an EFAULT and see if it's trapped
274 */
275 die_if_no_fixup("Fault in unaligned fixup", regs, 0);
276 return -EFAULT;
277 }
278
279 /*
280 * emulate the instruction in the delay slot
281 * - fetches the instruction from PC+2
282 */
283 static inline int handle_delayslot(struct pt_regs *regs,
284 insn_size_t old_instruction,
285 struct mem_access *ma)
286 {
287 insn_size_t instruction;
288 void __user *addr = (void __user *)(regs->pc +
289 instruction_size(old_instruction));
290
291 if (copy_from_user(&instruction, addr, sizeof(instruction))) {
292 /* the instruction-fetch faulted */
293 if (user_mode(regs))
294 return -EFAULT;
295
296 /* kernel */
297 die("delay-slot-insn faulting in handle_unaligned_delayslot",
298 regs, 0);
299 }
300
301 return handle_unaligned_ins(instruction, regs, ma);
302 }
303
304 /*
305 * handle an instruction that does an unaligned memory access
306 * - have to be careful of branch delay-slot instructions that fault
307 * SH3:
308 * - if the branch would be taken PC points to the branch
309 * - if the branch would not be taken, PC points to delay-slot
310 * SH4:
311 * - PC always points to delayed branch
312 * - return 0 if handled, -EFAULT if failed (may not return if in kernel)
313 */
314
315 /* Macros to determine offset from current PC for branch instructions */
316 /* Explicit type coercion is used to force sign extension where needed */
317 #define SH_PC_8BIT_OFFSET(instr) ((((signed char)(instr))*2) + 4)
318 #define SH_PC_12BIT_OFFSET(instr) ((((signed short)(instr<<4))>>3) + 4)
319
320 int handle_unaligned_access(insn_size_t instruction, struct pt_regs *regs,
321 struct mem_access *ma, int expected,
322 unsigned long address)
323 {
324 u_int rm;
325 int ret, index;
326
327 /*
328 * XXX: We can't handle mixed 16/32-bit instructions yet
329 */
330 if (instruction_size(instruction) != 2)
331 return -EINVAL;
332
333 index = (instruction>>8)&15; /* 0x0F00 */
334 rm = regs->regs[index];
335
336 /*
337 * Log the unexpected fixups, and then pass them on to perf.
338 *
339 * We intentionally don't report the expected cases to perf as
340 * otherwise the trapped I/O case will skew the results too much
341 * to be useful.
342 */
343 if (!expected) {
344 unaligned_fixups_notify(current, instruction, regs);
345 perf_sw_event(PERF_COUNT_SW_ALIGNMENT_FAULTS, 1,
346 regs, address);
347 }
348
349 ret = -EFAULT;
350 switch (instruction&0xF000) {
351 case 0x0000:
352 if (instruction==0x000B) {
353 /* rts */
354 ret = handle_delayslot(regs, instruction, ma);
355 if (ret==0)
356 regs->pc = regs->pr;
357 }
358 else if ((instruction&0x00FF)==0x0023) {
359 /* braf @Rm */
360 ret = handle_delayslot(regs, instruction, ma);
361 if (ret==0)
362 regs->pc += rm + 4;
363 }
364 else if ((instruction&0x00FF)==0x0003) {
365 /* bsrf @Rm */
366 ret = handle_delayslot(regs, instruction, ma);
367 if (ret==0) {
368 regs->pr = regs->pc + 4;
369 regs->pc += rm + 4;
370 }
371 }
372 else {
373 /* mov.[bwl] to/from memory via r0+rn */
374 goto simple;
375 }
376 break;
377
378 case 0x1000: /* mov.l Rm,@(disp,Rn) */
379 goto simple;
380
381 case 0x2000: /* mov.[bwl] to memory, possibly with pre-decrement */
382 goto simple;
383
384 case 0x4000:
385 if ((instruction&0x00FF)==0x002B) {
386 /* jmp @Rm */
387 ret = handle_delayslot(regs, instruction, ma);
388 if (ret==0)
389 regs->pc = rm;
390 }
391 else if ((instruction&0x00FF)==0x000B) {
392 /* jsr @Rm */
393 ret = handle_delayslot(regs, instruction, ma);
394 if (ret==0) {
395 regs->pr = regs->pc + 4;
396 regs->pc = rm;
397 }
398 }
399 else {
400 /* mov.[bwl] to/from memory via r0+rn */
401 goto simple;
402 }
403 break;
404
405 case 0x5000: /* mov.l @(disp,Rm),Rn */
406 goto simple;
407
408 case 0x6000: /* mov.[bwl] from memory, possibly with post-increment */
409 goto simple;
410
411 case 0x8000: /* bf lab, bf/s lab, bt lab, bt/s lab */
412 switch (instruction&0x0F00) {
413 case 0x0100: /* mov.w R0,@(disp,Rm) */
414 goto simple;
415 case 0x0500: /* mov.w @(disp,Rm),R0 */
416 goto simple;
417 case 0x0B00: /* bf lab - no delayslot*/
418 ret = 0;
419 break;
420 case 0x0F00: /* bf/s lab */
421 ret = handle_delayslot(regs, instruction, ma);
422 if (ret==0) {
423 #if defined(CONFIG_CPU_SH4) || defined(CONFIG_SH7705_CACHE_32KB)
424 if ((regs->sr & 0x00000001) != 0)
425 regs->pc += 4; /* next after slot */
426 else
427 #endif
428 regs->pc += SH_PC_8BIT_OFFSET(instruction);
429 }
430 break;
431 case 0x0900: /* bt lab - no delayslot */
432 ret = 0;
433 break;
434 case 0x0D00: /* bt/s lab */
435 ret = handle_delayslot(regs, instruction, ma);
436 if (ret==0) {
437 #if defined(CONFIG_CPU_SH4) || defined(CONFIG_SH7705_CACHE_32KB)
438 if ((regs->sr & 0x00000001) == 0)
439 regs->pc += 4; /* next after slot */
440 else
441 #endif
442 regs->pc += SH_PC_8BIT_OFFSET(instruction);
443 }
444 break;
445 }
446 break;
447
448 case 0x9000: /* mov.w @(disp,Rm),Rn */
449 goto simple;
450
451 case 0xA000: /* bra label */
452 ret = handle_delayslot(regs, instruction, ma);
453 if (ret==0)
454 regs->pc += SH_PC_12BIT_OFFSET(instruction);
455 break;
456
457 case 0xB000: /* bsr label */
458 ret = handle_delayslot(regs, instruction, ma);
459 if (ret==0) {
460 regs->pr = regs->pc + 4;
461 regs->pc += SH_PC_12BIT_OFFSET(instruction);
462 }
463 break;
464
465 case 0xD000: /* mov.l @(disp,Rm),Rn */
466 goto simple;
467 }
468 return ret;
469
470 /* handle non-delay-slot instruction */
471 simple:
472 ret = handle_unaligned_ins(instruction, regs, ma);
473 if (ret==0)
474 regs->pc += instruction_size(instruction);
475 return ret;
476 }
477
478 /*
479 * Handle various address error exceptions:
480 * - instruction address error:
481 * misaligned PC
482 * PC >= 0x80000000 in user mode
483 * - data address error (read and write)
484 * misaligned data access
485 * access to >= 0x80000000 is user mode
486 * Unfortuntaly we can't distinguish between instruction address error
487 * and data address errors caused by read accesses.
488 */
489 asmlinkage void do_address_error(struct pt_regs *regs,
490 unsigned long writeaccess,
491 unsigned long address)
492 {
493 unsigned long error_code = 0;
494 insn_size_t instruction;
495 int tmp;
496
497 /* Intentional ifdef */
498 #ifdef CONFIG_CPU_HAS_SR_RB
499 error_code = lookup_exception_vector();
500 #endif
501
502 if (user_mode(regs)) {
503 int si_code = BUS_ADRERR;
504 unsigned int user_action;
505
506 local_irq_enable();
507 inc_unaligned_user_access();
508
509 if (copy_from_user(&instruction, (insn_size_t __user *)(regs->pc & ~1),
510 sizeof(instruction))) {
511 goto uspace_segv;
512 }
513
514 /* shout about userspace fixups */
515 unaligned_fixups_notify(current, instruction, regs);
516
517 user_action = unaligned_user_action();
518 if (user_action & UM_FIXUP)
519 goto fixup;
520 if (user_action & UM_SIGNAL)
521 goto uspace_segv;
522 else {
523 /* ignore */
524 regs->pc += instruction_size(instruction);
525 return;
526 }
527
528 fixup:
529 /* bad PC is not something we can fix */
530 if (regs->pc & 1) {
531 si_code = BUS_ADRALN;
532 goto uspace_segv;
533 }
534
535 tmp = handle_unaligned_access(instruction, regs,
536 &user_mem_access, 0,
537 address);
538
539 if (tmp == 0)
540 return; /* sorted */
541 uspace_segv:
542 printk(KERN_NOTICE "Sending SIGBUS to \"%s\" due to unaligned "
543 "access (PC %lx PR %lx)\n", current->comm, regs->pc,
544 regs->pr);
545
546 force_sig_fault(SIGBUS, si_code, (void __user *)address);
547 } else {
548 inc_unaligned_kernel_access();
549
550 if (regs->pc & 1)
551 die("unaligned program counter", regs, error_code);
552
553 if (copy_from_kernel_nofault(&instruction, (void *)(regs->pc),
554 sizeof(instruction))) {
555 /* Argh. Fault on the instruction itself.
556 This should never happen non-SMP
557 */
558 die("insn faulting in do_address_error", regs, 0);
559 }
560
561 unaligned_fixups_notify(current, instruction, regs);
562
563 handle_unaligned_access(instruction, regs, &kernel_mem_access,
564 0, address);
565 }
566 }
567
568 #ifdef CONFIG_SH_DSP
569 /*
570 * SH-DSP support gerg@snapgear.com.
571 */
572 static int is_dsp_inst(struct pt_regs *regs)
573 {
574 unsigned short inst = 0;
575
576 /*
577 * Safe guard if DSP mode is already enabled or we're lacking
578 * the DSP altogether.
579 */
580 if (!(current_cpu_data.flags & CPU_HAS_DSP) || (regs->sr & SR_DSP))
581 return 0;
582
583 get_user(inst, ((unsigned short *) regs->pc));
584
585 inst &= 0xf000;
586
587 /* Check for any type of DSP or support instruction */
588 if ((inst == 0xf000) || (inst == 0x4000))
589 return 1;
590
591 return 0;
592 }
593 #else
594 static inline int is_dsp_inst(struct pt_regs *regs) { return 0; }
595 #endif /* CONFIG_SH_DSP */
596
597 #ifdef CONFIG_CPU_SH2A
598 asmlinkage void do_divide_error(unsigned long r4)
599 {
600 int code;
601
602 switch (r4) {
603 case TRAP_DIVZERO_ERROR:
604 code = FPE_INTDIV;
605 break;
606 case TRAP_DIVOVF_ERROR:
607 code = FPE_INTOVF;
608 break;
609 default:
610 /* Let gcc know unhandled cases don't make it past here */
611 return;
612 }
613 force_sig_fault(SIGFPE, code, NULL);
614 }
615 #endif
616
617 asmlinkage void do_reserved_inst(void)
618 {
619 struct pt_regs *regs = current_pt_regs();
620 unsigned long error_code;
621
622 #ifdef CONFIG_SH_FPU_EMU
623 unsigned short inst = 0;
624 int err;
625
626 get_user(inst, (unsigned short __user *)regs->pc);
627
628 err = do_fpu_inst(inst, regs);
629 if (!err) {
630 regs->pc += instruction_size(inst);
631 return;
632 }
633 /* not a FPU inst. */
634 #endif
635
636 #ifdef CONFIG_SH_DSP
637 /* Check if it's a DSP instruction */
638 if (is_dsp_inst(regs)) {
639 /* Enable DSP mode, and restart instruction. */
640 regs->sr |= SR_DSP;
641 /* Save DSP mode */
642 current->thread.dsp_status.status |= SR_DSP;
643 return;
644 }
645 #endif
646
647 error_code = lookup_exception_vector();
648
649 local_irq_enable();
650 force_sig(SIGILL);
651 die_if_no_fixup("reserved instruction", regs, error_code);
652 }
653
654 #ifdef CONFIG_SH_FPU_EMU
655 static int emulate_branch(unsigned short inst, struct pt_regs *regs)
656 {
657 /*
658 * bfs: 8fxx: PC+=d*2+4;
659 * bts: 8dxx: PC+=d*2+4;
660 * bra: axxx: PC+=D*2+4;
661 * bsr: bxxx: PC+=D*2+4 after PR=PC+4;
662 * braf:0x23: PC+=Rn*2+4;
663 * bsrf:0x03: PC+=Rn*2+4 after PR=PC+4;
664 * jmp: 4x2b: PC=Rn;
665 * jsr: 4x0b: PC=Rn after PR=PC+4;
666 * rts: 000b: PC=PR;
667 */
668 if (((inst & 0xf000) == 0xb000) || /* bsr */
669 ((inst & 0xf0ff) == 0x0003) || /* bsrf */
670 ((inst & 0xf0ff) == 0x400b)) /* jsr */
671 regs->pr = regs->pc + 4;
672
673 if ((inst & 0xfd00) == 0x8d00) { /* bfs, bts */
674 regs->pc += SH_PC_8BIT_OFFSET(inst);
675 return 0;
676 }
677
678 if ((inst & 0xe000) == 0xa000) { /* bra, bsr */
679 regs->pc += SH_PC_12BIT_OFFSET(inst);
680 return 0;
681 }
682
683 if ((inst & 0xf0df) == 0x0003) { /* braf, bsrf */
684 regs->pc += regs->regs[(inst & 0x0f00) >> 8] + 4;
685 return 0;
686 }
687
688 if ((inst & 0xf0df) == 0x400b) { /* jmp, jsr */
689 regs->pc = regs->regs[(inst & 0x0f00) >> 8];
690 return 0;
691 }
692
693 if ((inst & 0xffff) == 0x000b) { /* rts */
694 regs->pc = regs->pr;
695 return 0;
696 }
697
698 return 1;
699 }
700 #endif
701
702 asmlinkage void do_illegal_slot_inst(void)
703 {
704 struct pt_regs *regs = current_pt_regs();
705 unsigned long inst;
706
707 if (kprobe_handle_illslot(regs->pc) == 0)
708 return;
709
710 #ifdef CONFIG_SH_FPU_EMU
711 get_user(inst, (unsigned short __user *)regs->pc + 1);
712 if (!do_fpu_inst(inst, regs)) {
713 get_user(inst, (unsigned short __user *)regs->pc);
714 if (!emulate_branch(inst, regs))
715 return;
716 /* fault in branch.*/
717 }
718 /* not a FPU inst. */
719 #endif
720
721 inst = lookup_exception_vector();
722
723 local_irq_enable();
724 force_sig(SIGILL);
725 die_if_no_fixup("illegal slot instruction", regs, inst);
726 }
727
728 asmlinkage void do_exception_error(void)
729 {
730 long ex;
731
732 ex = lookup_exception_vector();
733 die_if_kernel("exception", current_pt_regs(), ex);
734 }
735
736 void per_cpu_trap_init(void)
737 {
738 extern void *vbr_base;
739
740 /* NOTE: The VBR value should be at P1
741 (or P2, virtural "fixed" address space).
742 It's definitely should not in physical address. */
743
744 asm volatile("ldc %0, vbr"
745 : /* no output */
746 : "r" (&vbr_base)
747 : "memory");
748
749 /* disable exception blocking now when the vbr has been setup */
750 clear_bl_bit();
751 }
752
753 void *set_exception_table_vec(unsigned int vec, void *handler)
754 {
755 extern void *exception_handling_table[];
756 void *old_handler;
757
758 old_handler = exception_handling_table[vec];
759 exception_handling_table[vec] = handler;
760 return old_handler;
761 }
762
763 void __init trap_init(void)
764 {
765 set_exception_table_vec(TRAP_RESERVED_INST, do_reserved_inst);
766 set_exception_table_vec(TRAP_ILLEGAL_SLOT_INST, do_illegal_slot_inst);
767
768 #if defined(CONFIG_CPU_SH4) && !defined(CONFIG_SH_FPU) || \
769 defined(CONFIG_SH_FPU_EMU)
770 /*
771 * For SH-4 lacking an FPU, treat floating point instructions as
772 * reserved. They'll be handled in the math-emu case, or faulted on
773 * otherwise.
774 */
775 set_exception_table_evt(0x800, do_reserved_inst);
776 set_exception_table_evt(0x820, do_illegal_slot_inst);
777 #elif defined(CONFIG_SH_FPU)
778 set_exception_table_evt(0x800, fpu_state_restore_trap_handler);
779 set_exception_table_evt(0x820, fpu_state_restore_trap_handler);
780 #endif
781
782 #ifdef CONFIG_CPU_SH2
783 set_exception_table_vec(TRAP_ADDRESS_ERROR, address_error_trap_handler);
784 #endif
785 #ifdef CONFIG_CPU_SH2A
786 set_exception_table_vec(TRAP_DIVZERO_ERROR, do_divide_error);
787 set_exception_table_vec(TRAP_DIVOVF_ERROR, do_divide_error);
788 #ifdef CONFIG_SH_FPU
789 set_exception_table_vec(TRAP_FPU_ERROR, fpu_error_trap_handler);
790 #endif
791 #endif
792
793 #ifdef TRAP_UBC
794 set_exception_table_vec(TRAP_UBC, breakpoint_trap_handler);
795 #endif
796 }
797
Linux® is a registered trademark of Linus Torvalds in the United States and other countries.
TOMOYO® is a registered trademark of NTT DATA CORPORATION.