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1// SPDX-License-Identifier: GPL-2.0
2/*
3 * arch/sh/kernel/traps_64.c
4 *
5 * Copyright (C) 2000, 2001 Paolo Alberelli
6 * Copyright (C) 2003, 2004 Paul Mundt
7 * Copyright (C) 2003, 2004 Richard Curnow
8 */
9#include <linux/sched.h>
10#include <linux/sched/debug.h>
11#include <linux/kernel.h>
12#include <linux/string.h>
13#include <linux/errno.h>
14#include <linux/ptrace.h>
15#include <linux/timer.h>
16#include <linux/mm.h>
17#include <linux/smp.h>
18#include <linux/init.h>
19#include <linux/delay.h>
20#include <linux/spinlock.h>
21#include <linux/kallsyms.h>
22#include <linux/interrupt.h>
23#include <linux/sysctl.h>
24#include <linux/module.h>
25#include <linux/perf_event.h>
26#include <linux/uaccess.h>
27#include <asm/io.h>
28#include <asm/alignment.h>
29#include <asm/processor.h>
30#include <asm/pgtable.h>
31#include <asm/fpu.h>
32
33static int read_opcode(reg_size_t pc, insn_size_t *result_opcode, int from_user_mode)
34{
35 int get_user_error;
36 unsigned long aligned_pc;
37 insn_size_t opcode;
38
39 if ((pc & 3) == 1) {
40 /* SHmedia */
41 aligned_pc = pc & ~3;
42 if (from_user_mode) {
43 if (!access_ok(aligned_pc, sizeof(insn_size_t))) {
44 get_user_error = -EFAULT;
45 } else {
46 get_user_error = __get_user(opcode, (insn_size_t *)aligned_pc);
47 *result_opcode = opcode;
48 }
49 return get_user_error;
50 } else {
51 /* If the fault was in the kernel, we can either read
52 * this directly, or if not, we fault.
53 */
54 *result_opcode = *(insn_size_t *)aligned_pc;
55 return 0;
56 }
57 } else if ((pc & 1) == 0) {
58 /* SHcompact */
59 /* TODO : provide handling for this. We don't really support
60 user-mode SHcompact yet, and for a kernel fault, this would
61 have to come from a module built for SHcompact. */
62 return -EFAULT;
63 } else {
64 /* misaligned */
65 return -EFAULT;
66 }
67}
68
69static int address_is_sign_extended(__u64 a)
70{
71 __u64 b;
72#if (NEFF == 32)
73 b = (__u64)(__s64)(__s32)(a & 0xffffffffUL);
74 return (b == a) ? 1 : 0;
75#else
76#error "Sign extend check only works for NEFF==32"
77#endif
78}
79
80/* return -1 for fault, 0 for OK */
81static int generate_and_check_address(struct pt_regs *regs,
82 insn_size_t opcode,
83 int displacement_not_indexed,
84 int width_shift,
85 __u64 *address)
86{
87 __u64 base_address, addr;
88 int basereg;
89
90 switch (1 << width_shift) {
91 case 1: inc_unaligned_byte_access(); break;
92 case 2: inc_unaligned_word_access(); break;
93 case 4: inc_unaligned_dword_access(); break;
94 case 8: inc_unaligned_multi_access(); break;
95 }
96
97 basereg = (opcode >> 20) & 0x3f;
98 base_address = regs->regs[basereg];
99 if (displacement_not_indexed) {
100 __s64 displacement;
101 displacement = (opcode >> 10) & 0x3ff;
102 displacement = sign_extend64(displacement, 9);
103 addr = (__u64)((__s64)base_address + (displacement << width_shift));
104 } else {
105 __u64 offset;
106 int offsetreg;
107 offsetreg = (opcode >> 10) & 0x3f;
108 offset = regs->regs[offsetreg];
109 addr = base_address + offset;
110 }
111
112 /* Check sign extended */
113 if (!address_is_sign_extended(addr))
114 return -1;
115
116 /* Check accessible. For misaligned access in the kernel, assume the
117 address is always accessible (and if not, just fault when the
118 load/store gets done.) */
119 if (user_mode(regs)) {
120 inc_unaligned_user_access();
121
122 if (addr >= TASK_SIZE)
123 return -1;
124 } else
125 inc_unaligned_kernel_access();
126
127 *address = addr;
128
129 perf_sw_event(PERF_COUNT_SW_EMULATION_FAULTS, 1, regs, addr);
130 unaligned_fixups_notify(current, opcode, regs);
131
132 return 0;
133}
134
135static void misaligned_kernel_word_load(__u64 address, int do_sign_extend, __u64 *result)
136{
137 unsigned short x;
138 unsigned char *p, *q;
139 p = (unsigned char *) (int) address;
140 q = (unsigned char *) &x;
141 q[0] = p[0];
142 q[1] = p[1];
143
144 if (do_sign_extend) {
145 *result = (__u64)(__s64) *(short *) &x;
146 } else {
147 *result = (__u64) x;
148 }
149}
150
151static void misaligned_kernel_word_store(__u64 address, __u64 value)
152{
153 unsigned short x;
154 unsigned char *p, *q;
155 p = (unsigned char *) (int) address;
156 q = (unsigned char *) &x;
157
158 x = (__u16) value;
159 p[0] = q[0];
160 p[1] = q[1];
161}
162
163static int misaligned_load(struct pt_regs *regs,
164 insn_size_t opcode,
165 int displacement_not_indexed,
166 int width_shift,
167 int do_sign_extend)
168{
169 /* Return -1 for a fault, 0 for OK */
170 int error;
171 int destreg;
172 __u64 address;
173
174 error = generate_and_check_address(regs, opcode,
175 displacement_not_indexed, width_shift, &address);
176 if (error < 0)
177 return error;
178
179 destreg = (opcode >> 4) & 0x3f;
180 if (user_mode(regs)) {
181 __u64 buffer;
182
183 if (!access_ok((unsigned long) address, 1UL<<width_shift)) {
184 return -1;
185 }
186
187 if (__copy_user(&buffer, (const void *)(int)address, (1 << width_shift)) > 0) {
188 return -1; /* fault */
189 }
190 switch (width_shift) {
191 case 1:
192 if (do_sign_extend) {
193 regs->regs[destreg] = (__u64)(__s64) *(__s16 *) &buffer;
194 } else {
195 regs->regs[destreg] = (__u64) *(__u16 *) &buffer;
196 }
197 break;
198 case 2:
199 regs->regs[destreg] = (__u64)(__s64) *(__s32 *) &buffer;
200 break;
201 case 3:
202 regs->regs[destreg] = buffer;
203 break;
204 default:
205 printk("Unexpected width_shift %d in misaligned_load, PC=%08lx\n",
206 width_shift, (unsigned long) regs->pc);
207 break;
208 }
209 } else {
210 /* kernel mode - we can take short cuts since if we fault, it's a genuine bug */
211 __u64 lo, hi;
212
213 switch (width_shift) {
214 case 1:
215 misaligned_kernel_word_load(address, do_sign_extend, ®s->regs[destreg]);
216 break;
217 case 2:
218 asm ("ldlo.l %1, 0, %0" : "=r" (lo) : "r" (address));
219 asm ("ldhi.l %1, 3, %0" : "=r" (hi) : "r" (address));
220 regs->regs[destreg] = lo | hi;
221 break;
222 case 3:
223 asm ("ldlo.q %1, 0, %0" : "=r" (lo) : "r" (address));
224 asm ("ldhi.q %1, 7, %0" : "=r" (hi) : "r" (address));
225 regs->regs[destreg] = lo | hi;
226 break;
227
228 default:
229 printk("Unexpected width_shift %d in misaligned_load, PC=%08lx\n",
230 width_shift, (unsigned long) regs->pc);
231 break;
232 }
233 }
234
235 return 0;
236}
237
238static int misaligned_store(struct pt_regs *regs,
239 insn_size_t opcode,
240 int displacement_not_indexed,
241 int width_shift)
242{
243 /* Return -1 for a fault, 0 for OK */
244 int error;
245 int srcreg;
246 __u64 address;
247
248 error = generate_and_check_address(regs, opcode,
249 displacement_not_indexed, width_shift, &address);
250 if (error < 0)
251 return error;
252
253 srcreg = (opcode >> 4) & 0x3f;
254 if (user_mode(regs)) {
255 __u64 buffer;
256
257 if (!access_ok((unsigned long) address, 1UL<<width_shift)) {
258 return -1;
259 }
260
261 switch (width_shift) {
262 case 1:
263 *(__u16 *) &buffer = (__u16) regs->regs[srcreg];
264 break;
265 case 2:
266 *(__u32 *) &buffer = (__u32) regs->regs[srcreg];
267 break;
268 case 3:
269 buffer = regs->regs[srcreg];
270 break;
271 default:
272 printk("Unexpected width_shift %d in misaligned_store, PC=%08lx\n",
273 width_shift, (unsigned long) regs->pc);
274 break;
275 }
276
277 if (__copy_user((void *)(int)address, &buffer, (1 << width_shift)) > 0) {
278 return -1; /* fault */
279 }
280 } else {
281 /* kernel mode - we can take short cuts since if we fault, it's a genuine bug */
282 __u64 val = regs->regs[srcreg];
283
284 switch (width_shift) {
285 case 1:
286 misaligned_kernel_word_store(address, val);
287 break;
288 case 2:
289 asm ("stlo.l %1, 0, %0" : : "r" (val), "r" (address));
290 asm ("sthi.l %1, 3, %0" : : "r" (val), "r" (address));
291 break;
292 case 3:
293 asm ("stlo.q %1, 0, %0" : : "r" (val), "r" (address));
294 asm ("sthi.q %1, 7, %0" : : "r" (val), "r" (address));
295 break;
296
297 default:
298 printk("Unexpected width_shift %d in misaligned_store, PC=%08lx\n",
299 width_shift, (unsigned long) regs->pc);
300 break;
301 }
302 }
303
304 return 0;
305}
306
307/* Never need to fix up misaligned FPU accesses within the kernel since that's a real
308 error. */
309static int misaligned_fpu_load(struct pt_regs *regs,
310 insn_size_t opcode,
311 int displacement_not_indexed,
312 int width_shift,
313 int do_paired_load)
314{
315 /* Return -1 for a fault, 0 for OK */
316 int error;
317 int destreg;
318 __u64 address;
319
320 error = generate_and_check_address(regs, opcode,
321 displacement_not_indexed, width_shift, &address);
322 if (error < 0)
323 return error;
324
325 destreg = (opcode >> 4) & 0x3f;
326 if (user_mode(regs)) {
327 __u64 buffer;
328 __u32 buflo, bufhi;
329
330 if (!access_ok((unsigned long) address, 1UL<<width_shift)) {
331 return -1;
332 }
333
334 if (__copy_user(&buffer, (const void *)(int)address, (1 << width_shift)) > 0) {
335 return -1; /* fault */
336 }
337 /* 'current' may be the current owner of the FPU state, so
338 context switch the registers into memory so they can be
339 indexed by register number. */
340 if (last_task_used_math == current) {
341 enable_fpu();
342 save_fpu(current);
343 disable_fpu();
344 last_task_used_math = NULL;
345 regs->sr |= SR_FD;
346 }
347
348 buflo = *(__u32*) &buffer;
349 bufhi = *(1 + (__u32*) &buffer);
350
351 switch (width_shift) {
352 case 2:
353 current->thread.xstate->hardfpu.fp_regs[destreg] = buflo;
354 break;
355 case 3:
356 if (do_paired_load) {
357 current->thread.xstate->hardfpu.fp_regs[destreg] = buflo;
358 current->thread.xstate->hardfpu.fp_regs[destreg+1] = bufhi;
359 } else {
360#if defined(CONFIG_CPU_LITTLE_ENDIAN)
361 current->thread.xstate->hardfpu.fp_regs[destreg] = bufhi;
362 current->thread.xstate->hardfpu.fp_regs[destreg+1] = buflo;
363#else
364 current->thread.xstate->hardfpu.fp_regs[destreg] = buflo;
365 current->thread.xstate->hardfpu.fp_regs[destreg+1] = bufhi;
366#endif
367 }
368 break;
369 default:
370 printk("Unexpected width_shift %d in misaligned_fpu_load, PC=%08lx\n",
371 width_shift, (unsigned long) regs->pc);
372 break;
373 }
374 return 0;
375 } else {
376 die ("Misaligned FPU load inside kernel", regs, 0);
377 return -1;
378 }
379}
380
381static int misaligned_fpu_store(struct pt_regs *regs,
382 insn_size_t opcode,
383 int displacement_not_indexed,
384 int width_shift,
385 int do_paired_load)
386{
387 /* Return -1 for a fault, 0 for OK */
388 int error;
389 int srcreg;
390 __u64 address;
391
392 error = generate_and_check_address(regs, opcode,
393 displacement_not_indexed, width_shift, &address);
394 if (error < 0)
395 return error;
396
397 srcreg = (opcode >> 4) & 0x3f;
398 if (user_mode(regs)) {
399 __u64 buffer;
400 /* Initialise these to NaNs. */
401 __u32 buflo=0xffffffffUL, bufhi=0xffffffffUL;
402
403 if (!access_ok((unsigned long) address, 1UL<<width_shift)) {
404 return -1;
405 }
406
407 /* 'current' may be the current owner of the FPU state, so
408 context switch the registers into memory so they can be
409 indexed by register number. */
410 if (last_task_used_math == current) {
411 enable_fpu();
412 save_fpu(current);
413 disable_fpu();
414 last_task_used_math = NULL;
415 regs->sr |= SR_FD;
416 }
417
418 switch (width_shift) {
419 case 2:
420 buflo = current->thread.xstate->hardfpu.fp_regs[srcreg];
421 break;
422 case 3:
423 if (do_paired_load) {
424 buflo = current->thread.xstate->hardfpu.fp_regs[srcreg];
425 bufhi = current->thread.xstate->hardfpu.fp_regs[srcreg+1];
426 } else {
427#if defined(CONFIG_CPU_LITTLE_ENDIAN)
428 bufhi = current->thread.xstate->hardfpu.fp_regs[srcreg];
429 buflo = current->thread.xstate->hardfpu.fp_regs[srcreg+1];
430#else
431 buflo = current->thread.xstate->hardfpu.fp_regs[srcreg];
432 bufhi = current->thread.xstate->hardfpu.fp_regs[srcreg+1];
433#endif
434 }
435 break;
436 default:
437 printk("Unexpected width_shift %d in misaligned_fpu_store, PC=%08lx\n",
438 width_shift, (unsigned long) regs->pc);
439 break;
440 }
441
442 *(__u32*) &buffer = buflo;
443 *(1 + (__u32*) &buffer) = bufhi;
444 if (__copy_user((void *)(int)address, &buffer, (1 << width_shift)) > 0) {
445 return -1; /* fault */
446 }
447 return 0;
448 } else {
449 die ("Misaligned FPU load inside kernel", regs, 0);
450 return -1;
451 }
452}
453
454static int misaligned_fixup(struct pt_regs *regs)
455{
456 insn_size_t opcode;
457 int error;
458 int major, minor;
459 unsigned int user_action;
460
461 user_action = unaligned_user_action();
462 if (!(user_action & UM_FIXUP))
463 return -1;
464
465 error = read_opcode(regs->pc, &opcode, user_mode(regs));
466 if (error < 0) {
467 return error;
468 }
469 major = (opcode >> 26) & 0x3f;
470 minor = (opcode >> 16) & 0xf;
471
472 switch (major) {
473 case (0x84>>2): /* LD.W */
474 error = misaligned_load(regs, opcode, 1, 1, 1);
475 break;
476 case (0xb0>>2): /* LD.UW */
477 error = misaligned_load(regs, opcode, 1, 1, 0);
478 break;
479 case (0x88>>2): /* LD.L */
480 error = misaligned_load(regs, opcode, 1, 2, 1);
481 break;
482 case (0x8c>>2): /* LD.Q */
483 error = misaligned_load(regs, opcode, 1, 3, 0);
484 break;
485
486 case (0xa4>>2): /* ST.W */
487 error = misaligned_store(regs, opcode, 1, 1);
488 break;
489 case (0xa8>>2): /* ST.L */
490 error = misaligned_store(regs, opcode, 1, 2);
491 break;
492 case (0xac>>2): /* ST.Q */
493 error = misaligned_store(regs, opcode, 1, 3);
494 break;
495
496 case (0x40>>2): /* indexed loads */
497 switch (minor) {
498 case 0x1: /* LDX.W */
499 error = misaligned_load(regs, opcode, 0, 1, 1);
500 break;
501 case 0x5: /* LDX.UW */
502 error = misaligned_load(regs, opcode, 0, 1, 0);
503 break;
504 case 0x2: /* LDX.L */
505 error = misaligned_load(regs, opcode, 0, 2, 1);
506 break;
507 case 0x3: /* LDX.Q */
508 error = misaligned_load(regs, opcode, 0, 3, 0);
509 break;
510 default:
511 error = -1;
512 break;
513 }
514 break;
515
516 case (0x60>>2): /* indexed stores */
517 switch (minor) {
518 case 0x1: /* STX.W */
519 error = misaligned_store(regs, opcode, 0, 1);
520 break;
521 case 0x2: /* STX.L */
522 error = misaligned_store(regs, opcode, 0, 2);
523 break;
524 case 0x3: /* STX.Q */
525 error = misaligned_store(regs, opcode, 0, 3);
526 break;
527 default:
528 error = -1;
529 break;
530 }
531 break;
532
533 case (0x94>>2): /* FLD.S */
534 error = misaligned_fpu_load(regs, opcode, 1, 2, 0);
535 break;
536 case (0x98>>2): /* FLD.P */
537 error = misaligned_fpu_load(regs, opcode, 1, 3, 1);
538 break;
539 case (0x9c>>2): /* FLD.D */
540 error = misaligned_fpu_load(regs, opcode, 1, 3, 0);
541 break;
542 case (0x1c>>2): /* floating indexed loads */
543 switch (minor) {
544 case 0x8: /* FLDX.S */
545 error = misaligned_fpu_load(regs, opcode, 0, 2, 0);
546 break;
547 case 0xd: /* FLDX.P */
548 error = misaligned_fpu_load(regs, opcode, 0, 3, 1);
549 break;
550 case 0x9: /* FLDX.D */
551 error = misaligned_fpu_load(regs, opcode, 0, 3, 0);
552 break;
553 default:
554 error = -1;
555 break;
556 }
557 break;
558 case (0xb4>>2): /* FLD.S */
559 error = misaligned_fpu_store(regs, opcode, 1, 2, 0);
560 break;
561 case (0xb8>>2): /* FLD.P */
562 error = misaligned_fpu_store(regs, opcode, 1, 3, 1);
563 break;
564 case (0xbc>>2): /* FLD.D */
565 error = misaligned_fpu_store(regs, opcode, 1, 3, 0);
566 break;
567 case (0x3c>>2): /* floating indexed stores */
568 switch (minor) {
569 case 0x8: /* FSTX.S */
570 error = misaligned_fpu_store(regs, opcode, 0, 2, 0);
571 break;
572 case 0xd: /* FSTX.P */
573 error = misaligned_fpu_store(regs, opcode, 0, 3, 1);
574 break;
575 case 0x9: /* FSTX.D */
576 error = misaligned_fpu_store(regs, opcode, 0, 3, 0);
577 break;
578 default:
579 error = -1;
580 break;
581 }
582 break;
583
584 default:
585 /* Fault */
586 error = -1;
587 break;
588 }
589
590 if (error < 0) {
591 return error;
592 } else {
593 regs->pc += 4; /* Skip the instruction that's just been emulated */
594 return 0;
595 }
596}
597
598static void do_unhandled_exception(int signr, char *str, unsigned long error,
599 struct pt_regs *regs)
600{
601 if (user_mode(regs))
602 force_sig(signr);
603
604 die_if_no_fixup(str, regs, error);
605}
606
607#define DO_ERROR(signr, str, name) \
608asmlinkage void do_##name(unsigned long error_code, struct pt_regs *regs) \
609{ \
610 do_unhandled_exception(signr, str, error_code, regs); \
611}
612
613DO_ERROR(SIGILL, "illegal slot instruction", illegal_slot_inst)
614DO_ERROR(SIGSEGV, "address error (exec)", address_error_exec)
615
616#if defined(CONFIG_SH64_ID2815_WORKAROUND)
617
618#define OPCODE_INVALID 0
619#define OPCODE_USER_VALID 1
620#define OPCODE_PRIV_VALID 2
621
622/* getcon/putcon - requires checking which control register is referenced. */
623#define OPCODE_CTRL_REG 3
624
625/* Table of valid opcodes for SHmedia mode.
626 Form a 10-bit value by concatenating the major/minor opcodes i.e.
627 opcode[31:26,20:16]. The 6 MSBs of this value index into the following
628 array. The 4 LSBs select the bit-pair in the entry (bits 1:0 correspond to
629 LSBs==4'b0000 etc). */
630static unsigned long shmedia_opcode_table[64] = {
631 0x55554044,0x54445055,0x15141514,0x14541414,0x00000000,0x10001000,0x01110055,0x04050015,
632 0x00000444,0xc0000000,0x44545515,0x40405555,0x55550015,0x10005555,0x55555505,0x04050000,
633 0x00000555,0x00000404,0x00040445,0x15151414,0x00000000,0x00000000,0x00000000,0x00000000,
634 0x00000055,0x40404444,0x00000404,0xc0009495,0x00000000,0x00000000,0x00000000,0x00000000,
635 0x55555555,0x55555555,0x55555555,0x55555555,0x55555555,0x55555555,0x55555555,0x55555555,
636 0x55555555,0x55555555,0x55555555,0x55555555,0x55555555,0x55555555,0x55555555,0x55555555,
637 0x80005050,0x04005055,0x55555555,0x55555555,0x55555555,0x55555555,0x55555555,0x55555555,
638 0x81055554,0x00000404,0x55555555,0x55555555,0x00000000,0x00000000,0x00000000,0x00000000
639};
640
641/* Workaround SH5-101 cut2 silicon defect #2815 :
642 in some situations, inter-mode branches from SHcompact -> SHmedia
643 which should take ITLBMISS or EXECPROT exceptions at the target
644 falsely take RESINST at the target instead. */
645void do_reserved_inst(unsigned long error_code, struct pt_regs *regs)
646{
647 insn_size_t opcode = 0x6ff4fff0; /* guaranteed reserved opcode */
648 unsigned long pc, aligned_pc;
649 unsigned long index, shift;
650 unsigned long major, minor, combined;
651 unsigned long reserved_field;
652 int opcode_state;
653 int get_user_error;
654 int signr = SIGILL;
655 char *exception_name = "reserved_instruction";
656
657 pc = regs->pc;
658
659 /* SHcompact is not handled */
660 if (unlikely((pc & 3) == 0))
661 goto out;
662
663 /* SHmedia : check for defect. This requires executable vmas
664 to be readable too. */
665 aligned_pc = pc & ~3;
666 if (!access_ok(aligned_pc, sizeof(insn_size_t)))
667 get_user_error = -EFAULT;
668 else
669 get_user_error = __get_user(opcode, (insn_size_t *)aligned_pc);
670
671 if (get_user_error < 0) {
672 /*
673 * Error trying to read opcode. This typically means a
674 * real fault, not a RESINST any more. So change the
675 * codes.
676 */
677 exception_name = "address error (exec)";
678 signr = SIGSEGV;
679 goto out;
680 }
681
682 /* These bits are currently reserved as zero in all valid opcodes */
683 reserved_field = opcode & 0xf;
684 if (unlikely(reserved_field))
685 goto out; /* invalid opcode */
686
687 major = (opcode >> 26) & 0x3f;
688 minor = (opcode >> 16) & 0xf;
689 combined = (major << 4) | minor;
690 index = major;
691 shift = minor << 1;
692 opcode_state = (shmedia_opcode_table[index] >> shift) & 0x3;
693 switch (opcode_state) {
694 case OPCODE_INVALID:
695 /* Trap. */
696 break;
697 case OPCODE_USER_VALID:
698 /*
699 * Restart the instruction: the branch to the instruction
700 * will now be from an RTE not from SHcompact so the
701 * silicon defect won't be triggered.
702 */
703 return;
704 case OPCODE_PRIV_VALID:
705 if (!user_mode(regs)) {
706 /*
707 * Should only ever get here if a module has
708 * SHcompact code inside it. If so, the same fix
709 * up is needed.
710 */
711 return; /* same reason */
712 }
713
714 /*
715 * Otherwise, user mode trying to execute a privileged
716 * instruction - fall through to trap.
717 */
718 break;
719 case OPCODE_CTRL_REG:
720 /* If in privileged mode, return as above. */
721 if (!user_mode(regs))
722 return;
723
724 /* In user mode ... */
725 if (combined == 0x9f) { /* GETCON */
726 unsigned long regno = (opcode >> 20) & 0x3f;
727
728 if (regno >= 62)
729 return;
730
731 /* reserved/privileged control register => trap */
732 } else if (combined == 0x1bf) { /* PUTCON */
733 unsigned long regno = (opcode >> 4) & 0x3f;
734
735 if (regno >= 62)
736 return;
737
738 /* reserved/privileged control register => trap */
739 }
740
741 break;
742 default:
743 /* Fall through to trap. */
744 break;
745 }
746
747out:
748 do_unhandled_exception(signr, exception_name, error_code, regs);
749}
750
751#else /* CONFIG_SH64_ID2815_WORKAROUND */
752
753/* If the workaround isn't needed, this is just a straightforward reserved
754 instruction */
755DO_ERROR(SIGILL, "reserved instruction", reserved_inst)
756
757#endif /* CONFIG_SH64_ID2815_WORKAROUND */
758
759/* Called with interrupts disabled */
760asmlinkage void do_exception_error(unsigned long ex, struct pt_regs *regs)
761{
762 die_if_kernel("exception", regs, ex);
763}
764
765asmlinkage int do_unknown_trapa(unsigned long scId, struct pt_regs *regs)
766{
767 /* Syscall debug */
768 printk("System call ID error: [0x1#args:8 #syscall:16 0x%lx]\n", scId);
769
770 die_if_kernel("unknown trapa", regs, scId);
771
772 return -ENOSYS;
773}
774
775/* Implement misaligned load/store handling for kernel (and optionally for user
776 mode too). Limitation : only SHmedia mode code is handled - there is no
777 handling at all for misaligned accesses occurring in SHcompact code yet. */
778
779asmlinkage void do_address_error_load(unsigned long error_code, struct pt_regs *regs)
780{
781 if (misaligned_fixup(regs) < 0)
782 do_unhandled_exception(SIGSEGV, "address error(load)",
783 error_code, regs);
784}
785
786asmlinkage void do_address_error_store(unsigned long error_code, struct pt_regs *regs)
787{
788 if (misaligned_fixup(regs) < 0)
789 do_unhandled_exception(SIGSEGV, "address error(store)",
790 error_code, regs);
791}
792
793asmlinkage void do_debug_interrupt(unsigned long code, struct pt_regs *regs)
794{
795 u64 peek_real_address_q(u64 addr);
796 u64 poke_real_address_q(u64 addr, u64 val);
797 unsigned long long DM_EXP_CAUSE_PHY = 0x0c100010;
798 unsigned long long exp_cause;
799 /* It's not worth ioremapping the debug module registers for the amount
800 of access we make to them - just go direct to their physical
801 addresses. */
802 exp_cause = peek_real_address_q(DM_EXP_CAUSE_PHY);
803 if (exp_cause & ~4)
804 printk("DM.EXP_CAUSE had unexpected bits set (=%08lx)\n",
805 (unsigned long)(exp_cause & 0xffffffff));
806 show_state();
807 /* Clear all DEBUGINT causes */
808 poke_real_address_q(DM_EXP_CAUSE_PHY, 0x0);
809}
810
811void per_cpu_trap_init(void)
812{
813 /* Nothing to do for now, VBR initialization later. */
814}
1/*
2 * arch/sh/kernel/traps_64.c
3 *
4 * Copyright (C) 2000, 2001 Paolo Alberelli
5 * Copyright (C) 2003, 2004 Paul Mundt
6 * Copyright (C) 2003, 2004 Richard Curnow
7 *
8 * This file is subject to the terms and conditions of the GNU General Public
9 * License. See the file "COPYING" in the main directory of this archive
10 * for more details.
11 */
12#include <linux/sched.h>
13#include <linux/kernel.h>
14#include <linux/string.h>
15#include <linux/errno.h>
16#include <linux/ptrace.h>
17#include <linux/timer.h>
18#include <linux/mm.h>
19#include <linux/smp.h>
20#include <linux/init.h>
21#include <linux/delay.h>
22#include <linux/spinlock.h>
23#include <linux/kallsyms.h>
24#include <linux/interrupt.h>
25#include <linux/sysctl.h>
26#include <linux/module.h>
27#include <linux/perf_event.h>
28#include <asm/uaccess.h>
29#include <asm/io.h>
30#include <linux/atomic.h>
31#include <asm/processor.h>
32#include <asm/pgtable.h>
33#include <asm/fpu.h>
34
35#undef DEBUG_EXCEPTION
36#ifdef DEBUG_EXCEPTION
37/* implemented in ../lib/dbg.c */
38extern void show_excp_regs(char *fname, int trapnr, int signr,
39 struct pt_regs *regs);
40#else
41#define show_excp_regs(a, b, c, d)
42#endif
43
44static void do_unhandled_exception(int trapnr, int signr, char *str, char *fn_name,
45 unsigned long error_code, struct pt_regs *regs, struct task_struct *tsk);
46
47#define DO_ERROR(trapnr, signr, str, name, tsk) \
48asmlinkage void do_##name(unsigned long error_code, struct pt_regs *regs) \
49{ \
50 do_unhandled_exception(trapnr, signr, str, __stringify(name), error_code, regs, current); \
51}
52
53static DEFINE_SPINLOCK(die_lock);
54
55void die(const char * str, struct pt_regs * regs, long err)
56{
57 console_verbose();
58 spin_lock_irq(&die_lock);
59 printk("%s: %lx\n", str, (err & 0xffffff));
60 show_regs(regs);
61 spin_unlock_irq(&die_lock);
62 do_exit(SIGSEGV);
63}
64
65static inline void die_if_kernel(const char * str, struct pt_regs * regs, long err)
66{
67 if (!user_mode(regs))
68 die(str, regs, err);
69}
70
71static void die_if_no_fixup(const char * str, struct pt_regs * regs, long err)
72{
73 if (!user_mode(regs)) {
74 const struct exception_table_entry *fixup;
75 fixup = search_exception_tables(regs->pc);
76 if (fixup) {
77 regs->pc = fixup->fixup;
78 return;
79 }
80 die(str, regs, err);
81 }
82}
83
84DO_ERROR(13, SIGILL, "illegal slot instruction", illegal_slot_inst, current)
85DO_ERROR(87, SIGSEGV, "address error (exec)", address_error_exec, current)
86
87
88/* Implement misaligned load/store handling for kernel (and optionally for user
89 mode too). Limitation : only SHmedia mode code is handled - there is no
90 handling at all for misaligned accesses occurring in SHcompact code yet. */
91
92static int misaligned_fixup(struct pt_regs *regs);
93
94asmlinkage void do_address_error_load(unsigned long error_code, struct pt_regs *regs)
95{
96 if (misaligned_fixup(regs) < 0) {
97 do_unhandled_exception(7, SIGSEGV, "address error(load)",
98 "do_address_error_load",
99 error_code, regs, current);
100 }
101 return;
102}
103
104asmlinkage void do_address_error_store(unsigned long error_code, struct pt_regs *regs)
105{
106 if (misaligned_fixup(regs) < 0) {
107 do_unhandled_exception(8, SIGSEGV, "address error(store)",
108 "do_address_error_store",
109 error_code, regs, current);
110 }
111 return;
112}
113
114#if defined(CONFIG_SH64_ID2815_WORKAROUND)
115
116#define OPCODE_INVALID 0
117#define OPCODE_USER_VALID 1
118#define OPCODE_PRIV_VALID 2
119
120/* getcon/putcon - requires checking which control register is referenced. */
121#define OPCODE_CTRL_REG 3
122
123/* Table of valid opcodes for SHmedia mode.
124 Form a 10-bit value by concatenating the major/minor opcodes i.e.
125 opcode[31:26,20:16]. The 6 MSBs of this value index into the following
126 array. The 4 LSBs select the bit-pair in the entry (bits 1:0 correspond to
127 LSBs==4'b0000 etc). */
128static unsigned long shmedia_opcode_table[64] = {
129 0x55554044,0x54445055,0x15141514,0x14541414,0x00000000,0x10001000,0x01110055,0x04050015,
130 0x00000444,0xc0000000,0x44545515,0x40405555,0x55550015,0x10005555,0x55555505,0x04050000,
131 0x00000555,0x00000404,0x00040445,0x15151414,0x00000000,0x00000000,0x00000000,0x00000000,
132 0x00000055,0x40404444,0x00000404,0xc0009495,0x00000000,0x00000000,0x00000000,0x00000000,
133 0x55555555,0x55555555,0x55555555,0x55555555,0x55555555,0x55555555,0x55555555,0x55555555,
134 0x55555555,0x55555555,0x55555555,0x55555555,0x55555555,0x55555555,0x55555555,0x55555555,
135 0x80005050,0x04005055,0x55555555,0x55555555,0x55555555,0x55555555,0x55555555,0x55555555,
136 0x81055554,0x00000404,0x55555555,0x55555555,0x00000000,0x00000000,0x00000000,0x00000000
137};
138
139void do_reserved_inst(unsigned long error_code, struct pt_regs *regs)
140{
141 /* Workaround SH5-101 cut2 silicon defect #2815 :
142 in some situations, inter-mode branches from SHcompact -> SHmedia
143 which should take ITLBMISS or EXECPROT exceptions at the target
144 falsely take RESINST at the target instead. */
145
146 unsigned long opcode = 0x6ff4fff0; /* guaranteed reserved opcode */
147 unsigned long pc, aligned_pc;
148 int get_user_error;
149 int trapnr = 12;
150 int signr = SIGILL;
151 char *exception_name = "reserved_instruction";
152
153 pc = regs->pc;
154 if ((pc & 3) == 1) {
155 /* SHmedia : check for defect. This requires executable vmas
156 to be readable too. */
157 aligned_pc = pc & ~3;
158 if (!access_ok(VERIFY_READ, aligned_pc, sizeof(unsigned long))) {
159 get_user_error = -EFAULT;
160 } else {
161 get_user_error = __get_user(opcode, (unsigned long *)aligned_pc);
162 }
163 if (get_user_error >= 0) {
164 unsigned long index, shift;
165 unsigned long major, minor, combined;
166 unsigned long reserved_field;
167 reserved_field = opcode & 0xf; /* These bits are currently reserved as zero in all valid opcodes */
168 major = (opcode >> 26) & 0x3f;
169 minor = (opcode >> 16) & 0xf;
170 combined = (major << 4) | minor;
171 index = major;
172 shift = minor << 1;
173 if (reserved_field == 0) {
174 int opcode_state = (shmedia_opcode_table[index] >> shift) & 0x3;
175 switch (opcode_state) {
176 case OPCODE_INVALID:
177 /* Trap. */
178 break;
179 case OPCODE_USER_VALID:
180 /* Restart the instruction : the branch to the instruction will now be from an RTE
181 not from SHcompact so the silicon defect won't be triggered. */
182 return;
183 case OPCODE_PRIV_VALID:
184 if (!user_mode(regs)) {
185 /* Should only ever get here if a module has
186 SHcompact code inside it. If so, the same fix up is needed. */
187 return; /* same reason */
188 }
189 /* Otherwise, user mode trying to execute a privileged instruction -
190 fall through to trap. */
191 break;
192 case OPCODE_CTRL_REG:
193 /* If in privileged mode, return as above. */
194 if (!user_mode(regs)) return;
195 /* In user mode ... */
196 if (combined == 0x9f) { /* GETCON */
197 unsigned long regno = (opcode >> 20) & 0x3f;
198 if (regno >= 62) {
199 return;
200 }
201 /* Otherwise, reserved or privileged control register, => trap */
202 } else if (combined == 0x1bf) { /* PUTCON */
203 unsigned long regno = (opcode >> 4) & 0x3f;
204 if (regno >= 62) {
205 return;
206 }
207 /* Otherwise, reserved or privileged control register, => trap */
208 } else {
209 /* Trap */
210 }
211 break;
212 default:
213 /* Fall through to trap. */
214 break;
215 }
216 }
217 /* fall through to normal resinst processing */
218 } else {
219 /* Error trying to read opcode. This typically means a
220 real fault, not a RESINST any more. So change the
221 codes. */
222 trapnr = 87;
223 exception_name = "address error (exec)";
224 signr = SIGSEGV;
225 }
226 }
227
228 do_unhandled_exception(trapnr, signr, exception_name, "do_reserved_inst", error_code, regs, current);
229}
230
231#else /* CONFIG_SH64_ID2815_WORKAROUND */
232
233/* If the workaround isn't needed, this is just a straightforward reserved
234 instruction */
235DO_ERROR(12, SIGILL, "reserved instruction", reserved_inst, current)
236
237#endif /* CONFIG_SH64_ID2815_WORKAROUND */
238
239/* Called with interrupts disabled */
240asmlinkage void do_exception_error(unsigned long ex, struct pt_regs *regs)
241{
242 show_excp_regs(__func__, -1, -1, regs);
243 die_if_kernel("exception", regs, ex);
244}
245
246int do_unknown_trapa(unsigned long scId, struct pt_regs *regs)
247{
248 /* Syscall debug */
249 printk("System call ID error: [0x1#args:8 #syscall:16 0x%lx]\n", scId);
250
251 die_if_kernel("unknown trapa", regs, scId);
252
253 return -ENOSYS;
254}
255
256void show_stack(struct task_struct *tsk, unsigned long *sp)
257{
258#ifdef CONFIG_KALLSYMS
259 extern void sh64_unwind(struct pt_regs *regs);
260 struct pt_regs *regs;
261
262 regs = tsk ? tsk->thread.kregs : NULL;
263
264 sh64_unwind(regs);
265#else
266 printk(KERN_ERR "Can't backtrace on sh64 without CONFIG_KALLSYMS\n");
267#endif
268}
269
270void show_task(unsigned long *sp)
271{
272 show_stack(NULL, sp);
273}
274
275void dump_stack(void)
276{
277 show_task(NULL);
278}
279/* Needed by any user of WARN_ON in view of the defn in include/asm-sh/bug.h */
280EXPORT_SYMBOL(dump_stack);
281
282static void do_unhandled_exception(int trapnr, int signr, char *str, char *fn_name,
283 unsigned long error_code, struct pt_regs *regs, struct task_struct *tsk)
284{
285 show_excp_regs(fn_name, trapnr, signr, regs);
286
287 if (user_mode(regs))
288 force_sig(signr, tsk);
289
290 die_if_no_fixup(str, regs, error_code);
291}
292
293static int read_opcode(unsigned long long pc, unsigned long *result_opcode, int from_user_mode)
294{
295 int get_user_error;
296 unsigned long aligned_pc;
297 unsigned long opcode;
298
299 if ((pc & 3) == 1) {
300 /* SHmedia */
301 aligned_pc = pc & ~3;
302 if (from_user_mode) {
303 if (!access_ok(VERIFY_READ, aligned_pc, sizeof(unsigned long))) {
304 get_user_error = -EFAULT;
305 } else {
306 get_user_error = __get_user(opcode, (unsigned long *)aligned_pc);
307 *result_opcode = opcode;
308 }
309 return get_user_error;
310 } else {
311 /* If the fault was in the kernel, we can either read
312 * this directly, or if not, we fault.
313 */
314 *result_opcode = *(unsigned long *) aligned_pc;
315 return 0;
316 }
317 } else if ((pc & 1) == 0) {
318 /* SHcompact */
319 /* TODO : provide handling for this. We don't really support
320 user-mode SHcompact yet, and for a kernel fault, this would
321 have to come from a module built for SHcompact. */
322 return -EFAULT;
323 } else {
324 /* misaligned */
325 return -EFAULT;
326 }
327}
328
329static int address_is_sign_extended(__u64 a)
330{
331 __u64 b;
332#if (NEFF == 32)
333 b = (__u64)(__s64)(__s32)(a & 0xffffffffUL);
334 return (b == a) ? 1 : 0;
335#else
336#error "Sign extend check only works for NEFF==32"
337#endif
338}
339
340static int generate_and_check_address(struct pt_regs *regs,
341 __u32 opcode,
342 int displacement_not_indexed,
343 int width_shift,
344 __u64 *address)
345{
346 /* return -1 for fault, 0 for OK */
347
348 __u64 base_address, addr;
349 int basereg;
350
351 basereg = (opcode >> 20) & 0x3f;
352 base_address = regs->regs[basereg];
353 if (displacement_not_indexed) {
354 __s64 displacement;
355 displacement = (opcode >> 10) & 0x3ff;
356 displacement = ((displacement << 54) >> 54); /* sign extend */
357 addr = (__u64)((__s64)base_address + (displacement << width_shift));
358 } else {
359 __u64 offset;
360 int offsetreg;
361 offsetreg = (opcode >> 10) & 0x3f;
362 offset = regs->regs[offsetreg];
363 addr = base_address + offset;
364 }
365
366 /* Check sign extended */
367 if (!address_is_sign_extended(addr)) {
368 return -1;
369 }
370
371 /* Check accessible. For misaligned access in the kernel, assume the
372 address is always accessible (and if not, just fault when the
373 load/store gets done.) */
374 if (user_mode(regs)) {
375 if (addr >= TASK_SIZE) {
376 return -1;
377 }
378 /* Do access_ok check later - it depends on whether it's a load or a store. */
379 }
380
381 *address = addr;
382 return 0;
383}
384
385static int user_mode_unaligned_fixup_count = 10;
386static int user_mode_unaligned_fixup_enable = 1;
387static int kernel_mode_unaligned_fixup_count = 32;
388
389static void misaligned_kernel_word_load(__u64 address, int do_sign_extend, __u64 *result)
390{
391 unsigned short x;
392 unsigned char *p, *q;
393 p = (unsigned char *) (int) address;
394 q = (unsigned char *) &x;
395 q[0] = p[0];
396 q[1] = p[1];
397
398 if (do_sign_extend) {
399 *result = (__u64)(__s64) *(short *) &x;
400 } else {
401 *result = (__u64) x;
402 }
403}
404
405static void misaligned_kernel_word_store(__u64 address, __u64 value)
406{
407 unsigned short x;
408 unsigned char *p, *q;
409 p = (unsigned char *) (int) address;
410 q = (unsigned char *) &x;
411
412 x = (__u16) value;
413 p[0] = q[0];
414 p[1] = q[1];
415}
416
417static int misaligned_load(struct pt_regs *regs,
418 __u32 opcode,
419 int displacement_not_indexed,
420 int width_shift,
421 int do_sign_extend)
422{
423 /* Return -1 for a fault, 0 for OK */
424 int error;
425 int destreg;
426 __u64 address;
427
428 error = generate_and_check_address(regs, opcode,
429 displacement_not_indexed, width_shift, &address);
430 if (error < 0) {
431 return error;
432 }
433
434 perf_sw_event(PERF_COUNT_SW_ALIGNMENT_FAULTS, 1, regs, address);
435
436 destreg = (opcode >> 4) & 0x3f;
437 if (user_mode(regs)) {
438 __u64 buffer;
439
440 if (!access_ok(VERIFY_READ, (unsigned long) address, 1UL<<width_shift)) {
441 return -1;
442 }
443
444 if (__copy_user(&buffer, (const void *)(int)address, (1 << width_shift)) > 0) {
445 return -1; /* fault */
446 }
447 switch (width_shift) {
448 case 1:
449 if (do_sign_extend) {
450 regs->regs[destreg] = (__u64)(__s64) *(__s16 *) &buffer;
451 } else {
452 regs->regs[destreg] = (__u64) *(__u16 *) &buffer;
453 }
454 break;
455 case 2:
456 regs->regs[destreg] = (__u64)(__s64) *(__s32 *) &buffer;
457 break;
458 case 3:
459 regs->regs[destreg] = buffer;
460 break;
461 default:
462 printk("Unexpected width_shift %d in misaligned_load, PC=%08lx\n",
463 width_shift, (unsigned long) regs->pc);
464 break;
465 }
466 } else {
467 /* kernel mode - we can take short cuts since if we fault, it's a genuine bug */
468 __u64 lo, hi;
469
470 switch (width_shift) {
471 case 1:
472 misaligned_kernel_word_load(address, do_sign_extend, ®s->regs[destreg]);
473 break;
474 case 2:
475 asm ("ldlo.l %1, 0, %0" : "=r" (lo) : "r" (address));
476 asm ("ldhi.l %1, 3, %0" : "=r" (hi) : "r" (address));
477 regs->regs[destreg] = lo | hi;
478 break;
479 case 3:
480 asm ("ldlo.q %1, 0, %0" : "=r" (lo) : "r" (address));
481 asm ("ldhi.q %1, 7, %0" : "=r" (hi) : "r" (address));
482 regs->regs[destreg] = lo | hi;
483 break;
484
485 default:
486 printk("Unexpected width_shift %d in misaligned_load, PC=%08lx\n",
487 width_shift, (unsigned long) regs->pc);
488 break;
489 }
490 }
491
492 return 0;
493
494}
495
496static int misaligned_store(struct pt_regs *regs,
497 __u32 opcode,
498 int displacement_not_indexed,
499 int width_shift)
500{
501 /* Return -1 for a fault, 0 for OK */
502 int error;
503 int srcreg;
504 __u64 address;
505
506 error = generate_and_check_address(regs, opcode,
507 displacement_not_indexed, width_shift, &address);
508 if (error < 0) {
509 return error;
510 }
511
512 perf_sw_event(PERF_COUNT_SW_ALIGNMENT_FAULTS, 1, regs, address);
513
514 srcreg = (opcode >> 4) & 0x3f;
515 if (user_mode(regs)) {
516 __u64 buffer;
517
518 if (!access_ok(VERIFY_WRITE, (unsigned long) address, 1UL<<width_shift)) {
519 return -1;
520 }
521
522 switch (width_shift) {
523 case 1:
524 *(__u16 *) &buffer = (__u16) regs->regs[srcreg];
525 break;
526 case 2:
527 *(__u32 *) &buffer = (__u32) regs->regs[srcreg];
528 break;
529 case 3:
530 buffer = regs->regs[srcreg];
531 break;
532 default:
533 printk("Unexpected width_shift %d in misaligned_store, PC=%08lx\n",
534 width_shift, (unsigned long) regs->pc);
535 break;
536 }
537
538 if (__copy_user((void *)(int)address, &buffer, (1 << width_shift)) > 0) {
539 return -1; /* fault */
540 }
541 } else {
542 /* kernel mode - we can take short cuts since if we fault, it's a genuine bug */
543 __u64 val = regs->regs[srcreg];
544
545 switch (width_shift) {
546 case 1:
547 misaligned_kernel_word_store(address, val);
548 break;
549 case 2:
550 asm ("stlo.l %1, 0, %0" : : "r" (val), "r" (address));
551 asm ("sthi.l %1, 3, %0" : : "r" (val), "r" (address));
552 break;
553 case 3:
554 asm ("stlo.q %1, 0, %0" : : "r" (val), "r" (address));
555 asm ("sthi.q %1, 7, %0" : : "r" (val), "r" (address));
556 break;
557
558 default:
559 printk("Unexpected width_shift %d in misaligned_store, PC=%08lx\n",
560 width_shift, (unsigned long) regs->pc);
561 break;
562 }
563 }
564
565 return 0;
566
567}
568
569/* Never need to fix up misaligned FPU accesses within the kernel since that's a real
570 error. */
571static int misaligned_fpu_load(struct pt_regs *regs,
572 __u32 opcode,
573 int displacement_not_indexed,
574 int width_shift,
575 int do_paired_load)
576{
577 /* Return -1 for a fault, 0 for OK */
578 int error;
579 int destreg;
580 __u64 address;
581
582 error = generate_and_check_address(regs, opcode,
583 displacement_not_indexed, width_shift, &address);
584 if (error < 0) {
585 return error;
586 }
587
588 perf_sw_event(PERF_COUNT_SW_EMULATION_FAULTS, 1, regs, address);
589
590 destreg = (opcode >> 4) & 0x3f;
591 if (user_mode(regs)) {
592 __u64 buffer;
593 __u32 buflo, bufhi;
594
595 if (!access_ok(VERIFY_READ, (unsigned long) address, 1UL<<width_shift)) {
596 return -1;
597 }
598
599 if (__copy_user(&buffer, (const void *)(int)address, (1 << width_shift)) > 0) {
600 return -1; /* fault */
601 }
602 /* 'current' may be the current owner of the FPU state, so
603 context switch the registers into memory so they can be
604 indexed by register number. */
605 if (last_task_used_math == current) {
606 enable_fpu();
607 save_fpu(current);
608 disable_fpu();
609 last_task_used_math = NULL;
610 regs->sr |= SR_FD;
611 }
612
613 buflo = *(__u32*) &buffer;
614 bufhi = *(1 + (__u32*) &buffer);
615
616 switch (width_shift) {
617 case 2:
618 current->thread.xstate->hardfpu.fp_regs[destreg] = buflo;
619 break;
620 case 3:
621 if (do_paired_load) {
622 current->thread.xstate->hardfpu.fp_regs[destreg] = buflo;
623 current->thread.xstate->hardfpu.fp_regs[destreg+1] = bufhi;
624 } else {
625#if defined(CONFIG_CPU_LITTLE_ENDIAN)
626 current->thread.xstate->hardfpu.fp_regs[destreg] = bufhi;
627 current->thread.xstate->hardfpu.fp_regs[destreg+1] = buflo;
628#else
629 current->thread.xstate->hardfpu.fp_regs[destreg] = buflo;
630 current->thread.xstate->hardfpu.fp_regs[destreg+1] = bufhi;
631#endif
632 }
633 break;
634 default:
635 printk("Unexpected width_shift %d in misaligned_fpu_load, PC=%08lx\n",
636 width_shift, (unsigned long) regs->pc);
637 break;
638 }
639 return 0;
640 } else {
641 die ("Misaligned FPU load inside kernel", regs, 0);
642 return -1;
643 }
644
645
646}
647
648static int misaligned_fpu_store(struct pt_regs *regs,
649 __u32 opcode,
650 int displacement_not_indexed,
651 int width_shift,
652 int do_paired_load)
653{
654 /* Return -1 for a fault, 0 for OK */
655 int error;
656 int srcreg;
657 __u64 address;
658
659 error = generate_and_check_address(regs, opcode,
660 displacement_not_indexed, width_shift, &address);
661 if (error < 0) {
662 return error;
663 }
664
665 perf_sw_event(PERF_COUNT_SW_EMULATION_FAULTS, 1, regs, address);
666
667 srcreg = (opcode >> 4) & 0x3f;
668 if (user_mode(regs)) {
669 __u64 buffer;
670 /* Initialise these to NaNs. */
671 __u32 buflo=0xffffffffUL, bufhi=0xffffffffUL;
672
673 if (!access_ok(VERIFY_WRITE, (unsigned long) address, 1UL<<width_shift)) {
674 return -1;
675 }
676
677 /* 'current' may be the current owner of the FPU state, so
678 context switch the registers into memory so they can be
679 indexed by register number. */
680 if (last_task_used_math == current) {
681 enable_fpu();
682 save_fpu(current);
683 disable_fpu();
684 last_task_used_math = NULL;
685 regs->sr |= SR_FD;
686 }
687
688 switch (width_shift) {
689 case 2:
690 buflo = current->thread.xstate->hardfpu.fp_regs[srcreg];
691 break;
692 case 3:
693 if (do_paired_load) {
694 buflo = current->thread.xstate->hardfpu.fp_regs[srcreg];
695 bufhi = current->thread.xstate->hardfpu.fp_regs[srcreg+1];
696 } else {
697#if defined(CONFIG_CPU_LITTLE_ENDIAN)
698 bufhi = current->thread.xstate->hardfpu.fp_regs[srcreg];
699 buflo = current->thread.xstate->hardfpu.fp_regs[srcreg+1];
700#else
701 buflo = current->thread.xstate->hardfpu.fp_regs[srcreg];
702 bufhi = current->thread.xstate->hardfpu.fp_regs[srcreg+1];
703#endif
704 }
705 break;
706 default:
707 printk("Unexpected width_shift %d in misaligned_fpu_store, PC=%08lx\n",
708 width_shift, (unsigned long) regs->pc);
709 break;
710 }
711
712 *(__u32*) &buffer = buflo;
713 *(1 + (__u32*) &buffer) = bufhi;
714 if (__copy_user((void *)(int)address, &buffer, (1 << width_shift)) > 0) {
715 return -1; /* fault */
716 }
717 return 0;
718 } else {
719 die ("Misaligned FPU load inside kernel", regs, 0);
720 return -1;
721 }
722}
723
724static int misaligned_fixup(struct pt_regs *regs)
725{
726 unsigned long opcode;
727 int error;
728 int major, minor;
729
730 if (!user_mode_unaligned_fixup_enable)
731 return -1;
732
733 error = read_opcode(regs->pc, &opcode, user_mode(regs));
734 if (error < 0) {
735 return error;
736 }
737 major = (opcode >> 26) & 0x3f;
738 minor = (opcode >> 16) & 0xf;
739
740 if (user_mode(regs) && (user_mode_unaligned_fixup_count > 0)) {
741 --user_mode_unaligned_fixup_count;
742 /* Only do 'count' worth of these reports, to remove a potential DoS against syslog */
743 printk("Fixing up unaligned userspace access in \"%s\" pid=%d pc=0x%08x ins=0x%08lx\n",
744 current->comm, task_pid_nr(current), (__u32)regs->pc, opcode);
745 } else if (!user_mode(regs) && (kernel_mode_unaligned_fixup_count > 0)) {
746 --kernel_mode_unaligned_fixup_count;
747 if (in_interrupt()) {
748 printk("Fixing up unaligned kernelspace access in interrupt pc=0x%08x ins=0x%08lx\n",
749 (__u32)regs->pc, opcode);
750 } else {
751 printk("Fixing up unaligned kernelspace access in \"%s\" pid=%d pc=0x%08x ins=0x%08lx\n",
752 current->comm, task_pid_nr(current), (__u32)regs->pc, opcode);
753 }
754 }
755
756
757 switch (major) {
758 case (0x84>>2): /* LD.W */
759 error = misaligned_load(regs, opcode, 1, 1, 1);
760 break;
761 case (0xb0>>2): /* LD.UW */
762 error = misaligned_load(regs, opcode, 1, 1, 0);
763 break;
764 case (0x88>>2): /* LD.L */
765 error = misaligned_load(regs, opcode, 1, 2, 1);
766 break;
767 case (0x8c>>2): /* LD.Q */
768 error = misaligned_load(regs, opcode, 1, 3, 0);
769 break;
770
771 case (0xa4>>2): /* ST.W */
772 error = misaligned_store(regs, opcode, 1, 1);
773 break;
774 case (0xa8>>2): /* ST.L */
775 error = misaligned_store(regs, opcode, 1, 2);
776 break;
777 case (0xac>>2): /* ST.Q */
778 error = misaligned_store(regs, opcode, 1, 3);
779 break;
780
781 case (0x40>>2): /* indexed loads */
782 switch (minor) {
783 case 0x1: /* LDX.W */
784 error = misaligned_load(regs, opcode, 0, 1, 1);
785 break;
786 case 0x5: /* LDX.UW */
787 error = misaligned_load(regs, opcode, 0, 1, 0);
788 break;
789 case 0x2: /* LDX.L */
790 error = misaligned_load(regs, opcode, 0, 2, 1);
791 break;
792 case 0x3: /* LDX.Q */
793 error = misaligned_load(regs, opcode, 0, 3, 0);
794 break;
795 default:
796 error = -1;
797 break;
798 }
799 break;
800
801 case (0x60>>2): /* indexed stores */
802 switch (minor) {
803 case 0x1: /* STX.W */
804 error = misaligned_store(regs, opcode, 0, 1);
805 break;
806 case 0x2: /* STX.L */
807 error = misaligned_store(regs, opcode, 0, 2);
808 break;
809 case 0x3: /* STX.Q */
810 error = misaligned_store(regs, opcode, 0, 3);
811 break;
812 default:
813 error = -1;
814 break;
815 }
816 break;
817
818 case (0x94>>2): /* FLD.S */
819 error = misaligned_fpu_load(regs, opcode, 1, 2, 0);
820 break;
821 case (0x98>>2): /* FLD.P */
822 error = misaligned_fpu_load(regs, opcode, 1, 3, 1);
823 break;
824 case (0x9c>>2): /* FLD.D */
825 error = misaligned_fpu_load(regs, opcode, 1, 3, 0);
826 break;
827 case (0x1c>>2): /* floating indexed loads */
828 switch (minor) {
829 case 0x8: /* FLDX.S */
830 error = misaligned_fpu_load(regs, opcode, 0, 2, 0);
831 break;
832 case 0xd: /* FLDX.P */
833 error = misaligned_fpu_load(regs, opcode, 0, 3, 1);
834 break;
835 case 0x9: /* FLDX.D */
836 error = misaligned_fpu_load(regs, opcode, 0, 3, 0);
837 break;
838 default:
839 error = -1;
840 break;
841 }
842 break;
843 case (0xb4>>2): /* FLD.S */
844 error = misaligned_fpu_store(regs, opcode, 1, 2, 0);
845 break;
846 case (0xb8>>2): /* FLD.P */
847 error = misaligned_fpu_store(regs, opcode, 1, 3, 1);
848 break;
849 case (0xbc>>2): /* FLD.D */
850 error = misaligned_fpu_store(regs, opcode, 1, 3, 0);
851 break;
852 case (0x3c>>2): /* floating indexed stores */
853 switch (minor) {
854 case 0x8: /* FSTX.S */
855 error = misaligned_fpu_store(regs, opcode, 0, 2, 0);
856 break;
857 case 0xd: /* FSTX.P */
858 error = misaligned_fpu_store(regs, opcode, 0, 3, 1);
859 break;
860 case 0x9: /* FSTX.D */
861 error = misaligned_fpu_store(regs, opcode, 0, 3, 0);
862 break;
863 default:
864 error = -1;
865 break;
866 }
867 break;
868
869 default:
870 /* Fault */
871 error = -1;
872 break;
873 }
874
875 if (error < 0) {
876 return error;
877 } else {
878 regs->pc += 4; /* Skip the instruction that's just been emulated */
879 return 0;
880 }
881
882}
883
884static ctl_table unaligned_table[] = {
885 {
886 .procname = "kernel_reports",
887 .data = &kernel_mode_unaligned_fixup_count,
888 .maxlen = sizeof(int),
889 .mode = 0644,
890 .proc_handler = proc_dointvec
891 },
892 {
893 .procname = "user_reports",
894 .data = &user_mode_unaligned_fixup_count,
895 .maxlen = sizeof(int),
896 .mode = 0644,
897 .proc_handler = proc_dointvec
898 },
899 {
900 .procname = "user_enable",
901 .data = &user_mode_unaligned_fixup_enable,
902 .maxlen = sizeof(int),
903 .mode = 0644,
904 .proc_handler = proc_dointvec},
905 {}
906};
907
908static ctl_table unaligned_root[] = {
909 {
910 .procname = "unaligned_fixup",
911 .mode = 0555,
912 .child = unaligned_table
913 },
914 {}
915};
916
917static ctl_table sh64_root[] = {
918 {
919 .procname = "sh64",
920 .mode = 0555,
921 .child = unaligned_root
922 },
923 {}
924};
925static struct ctl_table_header *sysctl_header;
926static int __init init_sysctl(void)
927{
928 sysctl_header = register_sysctl_table(sh64_root);
929 return 0;
930}
931
932__initcall(init_sysctl);
933
934
935asmlinkage void do_debug_interrupt(unsigned long code, struct pt_regs *regs)
936{
937 u64 peek_real_address_q(u64 addr);
938 u64 poke_real_address_q(u64 addr, u64 val);
939 unsigned long long DM_EXP_CAUSE_PHY = 0x0c100010;
940 unsigned long long exp_cause;
941 /* It's not worth ioremapping the debug module registers for the amount
942 of access we make to them - just go direct to their physical
943 addresses. */
944 exp_cause = peek_real_address_q(DM_EXP_CAUSE_PHY);
945 if (exp_cause & ~4) {
946 printk("DM.EXP_CAUSE had unexpected bits set (=%08lx)\n",
947 (unsigned long)(exp_cause & 0xffffffff));
948 }
949 show_state();
950 /* Clear all DEBUGINT causes */
951 poke_real_address_q(DM_EXP_CAUSE_PHY, 0x0);
952}
953
954void __cpuinit per_cpu_trap_init(void)
955{
956 /* Nothing to do for now, VBR initialization later. */
957}