Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound-2.6
[linux-2.6] / arch / frv / kernel / traps.c
1 /* traps.c: high-level exception handler for FR-V
2  *
3  * Copyright (C) 2003 Red Hat, Inc. All Rights Reserved.
4  * Written by David Howells (dhowells@redhat.com)
5  *
6  * This program is free software; you can redistribute it and/or
7  * modify it under the terms of the GNU General Public License
8  * as published by the Free Software Foundation; either version
9  * 2 of the License, or (at your option) any later version.
10  */
11
12 #include <linux/sched.h>
13 #include <linux/signal.h>
14 #include <linux/kernel.h>
15 #include <linux/mm.h>
16 #include <linux/types.h>
17 #include <linux/user.h>
18 #include <linux/string.h>
19 #include <linux/linkage.h>
20 #include <linux/init.h>
21 #include <linux/module.h>
22
23 #include <asm/asm-offsets.h>
24 #include <asm/setup.h>
25 #include <asm/fpu.h>
26 #include <asm/system.h>
27 #include <asm/uaccess.h>
28 #include <asm/pgtable.h>
29 #include <asm/siginfo.h>
30 #include <asm/unaligned.h>
31
32 void show_backtrace(struct pt_regs *, unsigned long);
33
34 extern asmlinkage void __break_hijack_kernel_event(void);
35
36 /*****************************************************************************/
37 /*
38  * instruction access error
39  */
40 asmlinkage void insn_access_error(unsigned long esfr1, unsigned long epcr0, unsigned long esr0)
41 {
42         siginfo_t info;
43
44         die_if_kernel("-- Insn Access Error --\n"
45                       "EPCR0 : %08lx\n"
46                       "ESR0  : %08lx\n",
47                       epcr0, esr0);
48
49         info.si_signo   = SIGSEGV;
50         info.si_code    = SEGV_ACCERR;
51         info.si_errno   = 0;
52         info.si_addr    = (void __user *) ((epcr0 & EPCR0_V) ? (epcr0 & EPCR0_PC) : __frame->pc);
53
54         force_sig_info(info.si_signo, &info, current);
55 } /* end insn_access_error() */
56
57 /*****************************************************************************/
58 /*
59  * handler for:
60  * - illegal instruction
61  * - privileged instruction
62  * - unsupported trap
63  * - debug exceptions
64  */
65 asmlinkage void illegal_instruction(unsigned long esfr1, unsigned long epcr0, unsigned long esr0)
66 {
67         siginfo_t info;
68
69         die_if_kernel("-- Illegal Instruction --\n"
70                       "EPCR0 : %08lx\n"
71                       "ESR0  : %08lx\n"
72                       "ESFR1 : %08lx\n",
73                       epcr0, esr0, esfr1);
74
75         info.si_errno   = 0;
76         info.si_addr    = (void __user *) ((epcr0 & EPCR0_V) ? (epcr0 & EPCR0_PC) : __frame->pc);
77
78         switch (__frame->tbr & TBR_TT) {
79         case TBR_TT_ILLEGAL_INSTR:
80                 info.si_signo   = SIGILL;
81                 info.si_code    = ILL_ILLOPC;
82                 break;
83         case TBR_TT_PRIV_INSTR:
84                 info.si_signo   = SIGILL;
85                 info.si_code    = ILL_PRVOPC;
86                 break;
87         case TBR_TT_TRAP2 ... TBR_TT_TRAP126:
88                 info.si_signo   = SIGILL;
89                 info.si_code    = ILL_ILLTRP;
90                 break;
91         /* GDB uses "tira gr0, #1" as a breakpoint instruction.  */
92         case TBR_TT_TRAP1:
93         case TBR_TT_BREAK:
94                 info.si_signo   = SIGTRAP;
95                 info.si_code    =
96                         (__frame->__status & REG__STATUS_STEPPED) ? TRAP_TRACE : TRAP_BRKPT;
97                 break;
98         }
99
100         force_sig_info(info.si_signo, &info, current);
101 } /* end illegal_instruction() */
102
103 /*****************************************************************************/
104 /*
105  * handle atomic operations with errors
106  * - arguments in gr8, gr9, gr10
107  * - original memory value placed in gr5
108  * - replacement memory value placed in gr9
109  */
110 asmlinkage void atomic_operation(unsigned long esfr1, unsigned long epcr0,
111                                  unsigned long esr0)
112 {
113         static DEFINE_SPINLOCK(atomic_op_lock);
114         unsigned long x, y, z;
115         unsigned long __user *p;
116         mm_segment_t oldfs;
117         siginfo_t info;
118         int ret;
119
120         y = 0;
121         z = 0;
122
123         oldfs = get_fs();
124         if (!user_mode(__frame))
125                 set_fs(KERNEL_DS);
126
127         switch (__frame->tbr & TBR_TT) {
128                 /* TIRA gr0,#120
129                  * u32 __atomic_user_cmpxchg32(u32 *ptr, u32 test, u32 new)
130                  */
131         case TBR_TT_ATOMIC_CMPXCHG32:
132                 p = (unsigned long __user *) __frame->gr8;
133                 x = __frame->gr9;
134                 y = __frame->gr10;
135
136                 for (;;) {
137                         ret = get_user(z, p);
138                         if (ret < 0)
139                                 goto error;
140
141                         if (z != x)
142                                 goto done;
143
144                         spin_lock_irq(&atomic_op_lock);
145
146                         if (__get_user(z, p) == 0) {
147                                 if (z != x)
148                                         goto done2;
149
150                                 if (__put_user(y, p) == 0)
151                                         goto done2;
152                                 goto error2;
153                         }
154
155                         spin_unlock_irq(&atomic_op_lock);
156                 }
157
158                 /* TIRA gr0,#121
159                  * u32 __atomic_kernel_xchg32(void *v, u32 new)
160                  */
161         case TBR_TT_ATOMIC_XCHG32:
162                 p = (unsigned long __user *) __frame->gr8;
163                 y = __frame->gr9;
164
165                 for (;;) {
166                         ret = get_user(z, p);
167                         if (ret < 0)
168                                 goto error;
169
170                         spin_lock_irq(&atomic_op_lock);
171
172                         if (__get_user(z, p) == 0) {
173                                 if (__put_user(y, p) == 0)
174                                         goto done2;
175                                 goto error2;
176                         }
177
178                         spin_unlock_irq(&atomic_op_lock);
179                 }
180
181                 /* TIRA gr0,#122
182                  * ulong __atomic_kernel_XOR_return(ulong i, ulong *v)
183                  */
184         case TBR_TT_ATOMIC_XOR:
185                 p = (unsigned long __user *) __frame->gr8;
186                 x = __frame->gr9;
187
188                 for (;;) {
189                         ret = get_user(z, p);
190                         if (ret < 0)
191                                 goto error;
192
193                         spin_lock_irq(&atomic_op_lock);
194
195                         if (__get_user(z, p) == 0) {
196                                 y = x ^ z;
197                                 if (__put_user(y, p) == 0)
198                                         goto done2;
199                                 goto error2;
200                         }
201
202                         spin_unlock_irq(&atomic_op_lock);
203                 }
204
205                 /* TIRA gr0,#123
206                  * ulong __atomic_kernel_OR_return(ulong i, ulong *v)
207                  */
208         case TBR_TT_ATOMIC_OR:
209                 p = (unsigned long __user *) __frame->gr8;
210                 x = __frame->gr9;
211
212                 for (;;) {
213                         ret = get_user(z, p);
214                         if (ret < 0)
215                                 goto error;
216
217                         spin_lock_irq(&atomic_op_lock);
218
219                         if (__get_user(z, p) == 0) {
220                                 y = x ^ z;
221                                 if (__put_user(y, p) == 0)
222                                         goto done2;
223                                 goto error2;
224                         }
225
226                         spin_unlock_irq(&atomic_op_lock);
227                 }
228
229                 /* TIRA gr0,#124
230                  * ulong __atomic_kernel_AND_return(ulong i, ulong *v)
231                  */
232         case TBR_TT_ATOMIC_AND:
233                 p = (unsigned long __user *) __frame->gr8;
234                 x = __frame->gr9;
235
236                 for (;;) {
237                         ret = get_user(z, p);
238                         if (ret < 0)
239                                 goto error;
240
241                         spin_lock_irq(&atomic_op_lock);
242
243                         if (__get_user(z, p) == 0) {
244                                 y = x & z;
245                                 if (__put_user(y, p) == 0)
246                                         goto done2;
247                                 goto error2;
248                         }
249
250                         spin_unlock_irq(&atomic_op_lock);
251                 }
252
253                 /* TIRA gr0,#125
254                  * int __atomic_user_sub_return(atomic_t *v, int i)
255                  */
256         case TBR_TT_ATOMIC_SUB:
257                 p = (unsigned long __user *) __frame->gr8;
258                 x = __frame->gr9;
259
260                 for (;;) {
261                         ret = get_user(z, p);
262                         if (ret < 0)
263                                 goto error;
264
265                         spin_lock_irq(&atomic_op_lock);
266
267                         if (__get_user(z, p) == 0) {
268                                 y = z - x;
269                                 if (__put_user(y, p) == 0)
270                                         goto done2;
271                                 goto error2;
272                         }
273
274                         spin_unlock_irq(&atomic_op_lock);
275                 }
276
277                 /* TIRA gr0,#126
278                  * int __atomic_user_add_return(atomic_t *v, int i)
279                  */
280         case TBR_TT_ATOMIC_ADD:
281                 p = (unsigned long __user *) __frame->gr8;
282                 x = __frame->gr9;
283
284                 for (;;) {
285                         ret = get_user(z, p);
286                         if (ret < 0)
287                                 goto error;
288
289                         spin_lock_irq(&atomic_op_lock);
290
291                         if (__get_user(z, p) == 0) {
292                                 y = z + x;
293                                 if (__put_user(y, p) == 0)
294                                         goto done2;
295                                 goto error2;
296                         }
297
298                         spin_unlock_irq(&atomic_op_lock);
299                 }
300
301         default:
302                 BUG();
303         }
304
305 done2:
306         spin_unlock_irq(&atomic_op_lock);
307 done:
308         if (!user_mode(__frame))
309                 set_fs(oldfs);
310         __frame->gr5 = z;
311         __frame->gr9 = y;
312         return;
313
314 error2:
315         spin_unlock_irq(&atomic_op_lock);
316 error:
317         if (!user_mode(__frame))
318                 set_fs(oldfs);
319         __frame->pc -= 4;
320
321         die_if_kernel("-- Atomic Op Error --\n");
322
323         info.si_signo   = SIGSEGV;
324         info.si_code    = SEGV_ACCERR;
325         info.si_errno   = 0;
326         info.si_addr    = (void __user *) __frame->pc;
327
328         force_sig_info(info.si_signo, &info, current);
329 }
330
331 /*****************************************************************************/
332 /*
333  *
334  */
335 asmlinkage void media_exception(unsigned long msr0, unsigned long msr1)
336 {
337         siginfo_t info;
338
339         die_if_kernel("-- Media Exception --\n"
340                       "MSR0 : %08lx\n"
341                       "MSR1 : %08lx\n",
342                       msr0, msr1);
343
344         info.si_signo   = SIGFPE;
345         info.si_code    = FPE_MDAOVF;
346         info.si_errno   = 0;
347         info.si_addr    = (void __user *) __frame->pc;
348
349         force_sig_info(info.si_signo, &info, current);
350 } /* end media_exception() */
351
352 /*****************************************************************************/
353 /*
354  * instruction or data access exception
355  */
356 asmlinkage void memory_access_exception(unsigned long esr0,
357                                         unsigned long ear0,
358                                         unsigned long epcr0)
359 {
360         siginfo_t info;
361
362 #ifdef CONFIG_MMU
363         unsigned long fixup;
364
365         fixup = search_exception_table(__frame->pc);
366         if (fixup) {
367                 __frame->pc = fixup;
368                 return;
369         }
370 #endif
371
372         die_if_kernel("-- Memory Access Exception --\n"
373                       "ESR0  : %08lx\n"
374                       "EAR0  : %08lx\n"
375                       "EPCR0 : %08lx\n",
376                       esr0, ear0, epcr0);
377
378         info.si_signo   = SIGSEGV;
379         info.si_code    = SEGV_ACCERR;
380         info.si_errno   = 0;
381         info.si_addr    = NULL;
382
383         if ((esr0 & (ESRx_VALID | ESR0_EAV)) == (ESRx_VALID | ESR0_EAV))
384                 info.si_addr = (void __user *) ear0;
385
386         force_sig_info(info.si_signo, &info, current);
387
388 } /* end memory_access_exception() */
389
390 /*****************************************************************************/
391 /*
392  * data access error
393  * - double-word data load from CPU control area (0xFExxxxxx)
394  * - read performed on inactive or self-refreshing SDRAM
395  * - error notification from slave device
396  * - misaligned address
397  * - access to out of bounds memory region
398  * - user mode accessing privileged memory region
399  * - write to R/O memory region
400  */
401 asmlinkage void data_access_error(unsigned long esfr1, unsigned long esr15, unsigned long ear15)
402 {
403         siginfo_t info;
404
405         die_if_kernel("-- Data Access Error --\n"
406                       "ESR15 : %08lx\n"
407                       "EAR15 : %08lx\n",
408                       esr15, ear15);
409
410         info.si_signo   = SIGSEGV;
411         info.si_code    = SEGV_ACCERR;
412         info.si_errno   = 0;
413         info.si_addr    = (void __user *)
414                 (((esr15 & (ESRx_VALID|ESR15_EAV)) == (ESRx_VALID|ESR15_EAV)) ? ear15 : 0);
415
416         force_sig_info(info.si_signo, &info, current);
417 } /* end data_access_error() */
418
419 /*****************************************************************************/
420 /*
421  * data store error - should only happen if accessing inactive or self-refreshing SDRAM
422  */
423 asmlinkage void data_store_error(unsigned long esfr1, unsigned long esr15)
424 {
425         die_if_kernel("-- Data Store Error --\n"
426                       "ESR15 : %08lx\n",
427                       esr15);
428         BUG();
429 } /* end data_store_error() */
430
431 /*****************************************************************************/
432 /*
433  *
434  */
435 asmlinkage void division_exception(unsigned long esfr1, unsigned long esr0, unsigned long isr)
436 {
437         siginfo_t info;
438
439         die_if_kernel("-- Division Exception --\n"
440                       "ESR0 : %08lx\n"
441                       "ISR  : %08lx\n",
442                       esr0, isr);
443
444         info.si_signo   = SIGFPE;
445         info.si_code    = FPE_INTDIV;
446         info.si_errno   = 0;
447         info.si_addr    = (void __user *) __frame->pc;
448
449         force_sig_info(info.si_signo, &info, current);
450 } /* end division_exception() */
451
452 /*****************************************************************************/
453 /*
454  *
455  */
456 asmlinkage void compound_exception(unsigned long esfr1,
457                                    unsigned long esr0, unsigned long esr14, unsigned long esr15,
458                                    unsigned long msr0, unsigned long msr1)
459 {
460         die_if_kernel("-- Compound Exception --\n"
461                       "ESR0  : %08lx\n"
462                       "ESR15 : %08lx\n"
463                       "ESR15 : %08lx\n"
464                       "MSR0  : %08lx\n"
465                       "MSR1  : %08lx\n",
466                       esr0, esr14, esr15, msr0, msr1);
467         BUG();
468 } /* end compound_exception() */
469
470 /*****************************************************************************/
471 /*
472  * The architecture-independent backtrace generator
473  */
474 void dump_stack(void)
475 {
476         show_stack(NULL, NULL);
477 }
478
479 EXPORT_SYMBOL(dump_stack);
480
481 void show_stack(struct task_struct *task, unsigned long *sp)
482 {
483 }
484
485 void show_trace_task(struct task_struct *tsk)
486 {
487         printk("CONTEXT: stack=0x%lx frame=0x%p LR=0x%lx RET=0x%lx\n",
488                tsk->thread.sp, tsk->thread.frame, tsk->thread.lr, tsk->thread.sched_lr);
489 }
490
491 static const char *regnames[] = {
492         "PSR ", "ISR ", "CCR ", "CCCR",
493         "LR  ", "LCR ", "PC  ", "_stt",
494         "sys ", "GR8*", "GNE0", "GNE1",
495         "IACH", "IACL",
496         "TBR ", "SP  ", "FP  ", "GR3 ",
497         "GR4 ", "GR5 ", "GR6 ", "GR7 ",
498         "GR8 ", "GR9 ", "GR10", "GR11",
499         "GR12", "GR13", "GR14", "GR15",
500         "GR16", "GR17", "GR18", "GR19",
501         "GR20", "GR21", "GR22", "GR23",
502         "GR24", "GR25", "GR26", "GR27",
503         "EFRM", "CURR", "GR30", "BFRM"
504 };
505
506 void show_regs(struct pt_regs *regs)
507 {
508         unsigned long *reg;
509         int loop;
510
511         printk("\n");
512
513         printk("Frame: @%08lx [%s]\n",
514                (unsigned long) regs,
515                regs->psr & PSR_S ? "kernel" : "user");
516
517         reg = (unsigned long *) regs;
518         for (loop = 0; loop < NR_PT_REGS; loop++) {
519                 printk("%s %08lx", regnames[loop + 0], reg[loop + 0]);
520
521                 if (loop == NR_PT_REGS - 1 || loop % 5 == 4)
522                         printk("\n");
523                 else
524                         printk(" | ");
525         }
526
527         printk("Process %s (pid: %d)\n", current->comm, current->pid);
528 }
529
530 void die_if_kernel(const char *str, ...)
531 {
532         char buffer[256];
533         va_list va;
534
535         if (user_mode(__frame))
536                 return;
537
538         va_start(va, str);
539         vsprintf(buffer, str, va);
540         va_end(va);
541
542         console_verbose();
543         printk("\n===================================\n");
544         printk("%s\n", buffer);
545         show_backtrace(__frame, 0);
546
547         __break_hijack_kernel_event();
548         do_exit(SIGSEGV);
549 }
550
551 /*****************************************************************************/
552 /*
553  * dump the contents of an exception frame
554  */
555 static void show_backtrace_regs(struct pt_regs *frame)
556 {
557         unsigned long *reg;
558         int loop;
559
560         /* print the registers for this frame */
561         printk("<-- %s Frame: @%p -->\n",
562                frame->psr & PSR_S ? "Kernel Mode" : "User Mode",
563                frame);
564
565         reg = (unsigned long *) frame;
566         for (loop = 0; loop < NR_PT_REGS; loop++) {
567                 printk("%s %08lx", regnames[loop + 0], reg[loop + 0]);
568
569                 if (loop == NR_PT_REGS - 1 || loop % 5 == 4)
570                         printk("\n");
571                 else
572                         printk(" | ");
573         }
574
575         printk("--------\n");
576 } /* end show_backtrace_regs() */
577
578 /*****************************************************************************/
579 /*
580  * generate a backtrace of the kernel stack
581  */
582 void show_backtrace(struct pt_regs *frame, unsigned long sp)
583 {
584         struct pt_regs *frame0;
585         unsigned long tos = 0, stop = 0, base;
586         int format;
587
588         base = ((((unsigned long) frame) + 8191) & ~8191) - sizeof(struct user_context);
589         frame0 = (struct pt_regs *) base;
590
591         if (sp) {
592                 tos = sp;
593                 stop = (unsigned long) frame;
594         }
595
596         printk("\nProcess %s (pid: %d)\n\n", current->comm, current->pid);
597
598         for (;;) {
599                 /* dump stack segment between frames */
600                 //printk("%08lx -> %08lx\n", tos, stop);
601                 format = 0;
602                 while (tos < stop) {
603                         if (format == 0)
604                                 printk(" %04lx :", tos & 0xffff);
605
606                         printk(" %08lx", *(unsigned long *) tos);
607
608                         tos += 4;
609                         format++;
610                         if (format == 8) {
611                                 printk("\n");
612                                 format = 0;
613                         }
614                 }
615
616                 if (format > 0)
617                         printk("\n");
618
619                 /* dump frame 0 outside of the loop */
620                 if (frame == frame0)
621                         break;
622
623                 tos = frame->sp;
624                 if (((unsigned long) frame) + sizeof(*frame) != tos) {
625                         printk("-- TOS %08lx does not follow frame %p --\n",
626                                tos, frame);
627                         break;
628                 }
629
630                 show_backtrace_regs(frame);
631
632                 /* dump the stack between this frame and the next */
633                 stop = (unsigned long) frame->next_frame;
634                 if (stop != base &&
635                     (stop < tos ||
636                      stop > base ||
637                      (stop < base && stop + sizeof(*frame) > base) ||
638                      stop & 3)) {
639                         printk("-- next_frame %08lx is invalid (range %08lx-%08lx) --\n",
640                                stop, tos, base);
641                         break;
642                 }
643
644                 /* move to next frame */
645                 frame = frame->next_frame;
646         }
647
648         /* we can always dump frame 0, even if the rest of the stack is corrupt */
649         show_backtrace_regs(frame0);
650
651 } /* end show_backtrace() */
652
653 /*****************************************************************************/
654 /*
655  * initialise traps
656  */
657 void __init trap_init (void)
658 {
659 } /* end trap_init() */