summaryrefslogtreecommitdiffstats
path: root/arch/blackfin/kernel/traps.c
blob: d0f6754220746c49a0f20c55876e1ed2237a850f (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
/*
 * File:         arch/blackfin/kernel/traps.c
 * Based on:
 * Author:       Hamish Macdonald
 *
 * Created:
 * Description:  uses S/W interrupt 15 for the system calls
 *
 * Modified:
 *               Copyright 2004-2006 Analog Devices Inc.
 *
 * Bugs:         Enter bugs at http://blackfin.uclinux.org/
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, see the file COPYING, or write
 * to the Free Software Foundation, Inc.,
 * 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
 */

#include <linux/uaccess.h>
#include <linux/interrupt.h>
#include <linux/module.h>
#include <linux/kallsyms.h>
#include <linux/fs.h>
#include <asm/traps.h>
#include <asm/cacheflush.h>
#include <asm/blackfin.h>
#include <asm/irq_handler.h>
#include <linux/irq.h>
#include <asm/trace.h>
#include <asm/fixed_code.h>
#include <asm/dma.h>

#ifdef CONFIG_KGDB
# include <linux/debugger.h>
# include <linux/kgdb.h>

# define CHK_DEBUGGER_TRAP() \
	do { \
		CHK_DEBUGGER(trapnr, sig, info.si_code, fp, ); \
	} while (0)
# define CHK_DEBUGGER_TRAP_MAYBE() \
	do { \
		if (kgdb_connected) \
			CHK_DEBUGGER_TRAP(); \
	} while (0)
#else
# define CHK_DEBUGGER_TRAP() do { } while (0)
# define CHK_DEBUGGER_TRAP_MAYBE() do { } while (0)
#endif

/* Initiate the event table handler */
void __init trap_init(void)
{
	CSYNC();
	bfin_write_EVT3(trap);
	CSYNC();
}

int kstack_depth_to_print = 48;

static void decode_address(char *buf, unsigned long address)
{
	struct vm_list_struct *vml;
	struct task_struct *p;
	struct mm_struct *mm;
	unsigned long flags, offset;
	unsigned char in_atomic = (bfin_read_IPEND() & 0x10) || in_atomic();

#ifdef CONFIG_KALLSYMS
	unsigned long symsize;
	const char *symname;
	char *modname;
	char *delim = ":";
	char namebuf[128];

	/* look up the address and see if we are in kernel space */
	symname = kallsyms_lookup(address, &symsize, &offset, &modname, namebuf);

	if (symname) {
		/* yeah! kernel space! */
		if (!modname)
			modname = delim = "";
		sprintf(buf, "<0x%p> { %s%s%s%s + 0x%lx }",
		              (void *)address, delim, modname, delim, symname,
		              (unsigned long)offset);
		return;

	}
#endif

	/* Problem in fixed code section? */
	if (address >= FIXED_CODE_START && address < FIXED_CODE_END) {
		sprintf(buf, "<0x%p> /* Maybe fixed code section */", (void *)address);
		return;
	}

	/* Problem somewhere before the kernel start address */
	if (address < CONFIG_BOOT_LOAD) {
		sprintf(buf, "<0x%p> /* Maybe null pointer? */", (void *)address);
		return;
	}

	/* looks like we're off in user-land, so let's walk all the
	 * mappings of all our processes and see if we can't be a whee
	 * bit more specific
	 */
	write_lock_irqsave(&tasklist_lock, flags);
	for_each_process(p) {
		mm = (in_atomic ? p->mm : get_task_mm(p));
		if (!mm)
			continue;

		vml = mm->context.vmlist;
		while (vml) {
			struct vm_area_struct *vma = vml->vma;

			if (address >= vma->vm_start && address < vma->vm_end) {
				char _tmpbuf[256];
				char *name = p->comm;
				struct file *file = vma->vm_file;

				if (file)
					name = d_path(&file->f_path, _tmpbuf,
						      sizeof(_tmpbuf));

				/* FLAT does not have its text aligned to the start of
				 * the map while FDPIC ELF does ...
				 */

				/* before we can check flat/fdpic, we need to
				 * make sure current is valid
				 */
				if ((unsigned long)current >= FIXED_CODE_START &&
				    !((unsigned long)current & 0x3)) {
					if (current->mm &&
					    (address > current->mm->start_code) &&
					    (address < current->mm->end_code))
						offset = address - current->mm->start_code;
					else
						offset = (address - vma->vm_start) +
							 (vma->vm_pgoff << PAGE_SHIFT);

					sprintf(buf, "<0x%p> [ %s + 0x%lx ]",
						(void *)address, name, offset);
				} else
					sprintf(buf, "<0x%p> [ %s vma:0x%lx-0x%lx]",
						(void *)address, name,
						vma->vm_start, vma->vm_end);

				if (!in_atomic)
					mmput(mm);

				goto done;
			}

			vml = vml->next;
		}
		if (!in_atomic)
			mmput(mm);
	}

	/* we were unable to find this address anywhere */
	sprintf(buf, "<0x%p> /* unknown address */", (void *)address);

done:
	write_unlock_irqrestore(&tasklist_lock, flags);
}

asmlinkage void double_fault_c(struct pt_regs *fp)
{
	console_verbose();
	oops_in_progress = 1;
	printk(KERN_EMERG "\n" KERN_EMERG "Double Fault\n");
	dump_bfin_process(fp);
	dump_bfin_mem(fp);
	show_regs(fp);
	panic("Double Fault - unrecoverable event\n");

}

asmlinkage void trap_c(struct pt_regs *fp)
{
#ifdef CONFIG_DEBUG_BFIN_HWTRACE_ON
	int j;
#endif
	int sig = 0;
	siginfo_t info;
	unsigned long trapnr = fp->seqstat & SEQSTAT_EXCAUSE;

	trace_buffer_save(j);

	/* Important - be very careful dereferncing pointers - will lead to
	 * double faults if the stack has become corrupt
	 */

	/* If the fault was caused by a kernel thread, or interrupt handler
	 * we will kernel panic, so the system reboots.
	 * If KGDB is enabled, don't set this for kernel breakpoints
	*/

	/* TODO: check to see if we are in some sort of deferred HWERR
	 * that we should be able to recover from, not kernel panic
	 */
	if ((bfin_read_IPEND() & 0xFFC0) && (trapnr != VEC_STEP)
#ifdef CONFIG_KGDB
		&& (trapnr != VEC_EXCPT02)
#endif
	){
		console_verbose();
		oops_in_progress = 1;
	} else if (current) {
		if (current->mm == NULL) {
			console_verbose();
			oops_in_progress = 1;
		}
	}

	/* trap_c() will be called for exceptions. During exceptions
	 * processing, the pc value should be set with retx value.
	 * With this change we can cleanup some code in signal.c- TODO
	 */
	fp->orig_pc = fp->retx;
	/* printk("exception: 0x%x, ipend=%x, reti=%x, retx=%x\n",
		trapnr, fp->ipend, fp->pc, fp->retx); */

	/* send the appropriate signal to the user program */
	switch (trapnr) {

	/* This table works in conjuction with the one in ./mach-common/entry.S
	 * Some exceptions are handled there (in assembly, in exception space)
	 * Some are handled here, (in C, in interrupt space)
	 * Some, like CPLB, are handled in both, where the normal path is
	 * handled in assembly/exception space, and the error path is handled
	 * here
	 */

	/* 0x00 - Linux Syscall, getting here is an error */
	/* 0x01 - userspace gdb breakpoint, handled here */
	case VEC_EXCPT01:
		info.si_code = TRAP_ILLTRAP;
		sig = SIGTRAP;
		CHK_DEBUGGER_TRAP_MAYBE();
		/* Check if this is a breakpoint in kernel space */
		if (fp->ipend & 0xffc0)
			return;
		else
			break;
#ifdef CONFIG_KGDB
	case VEC_EXCPT02 :		 /* gdb connection */
		info.si_code = TRAP_ILLTRAP;
		sig = SIGTRAP;
		CHK_DEBUGGER_TRAP();
		return;
#else
	/* 0x02 - User Defined, Caught by default */
#endif
	/* 0x03 - User Defined, userspace stack overflow */
	case VEC_EXCPT03:
		info.si_code = SEGV_STACKFLOW;
		sig = SIGSEGV;
		printk(KERN_NOTICE EXC_0x03(KERN_NOTICE));
		CHK_DEBUGGER_TRAP();
		break;
	/* 0x04 - User Defined, Caught by default */
	/* 0x05 - User Defined, Caught by default */
	/* 0x06 - User Defined, Caught by default */
	/* 0x07 - User Defined, Caught by default */
	/* 0x08 - User Defined, Caught by default */
	/* 0x09 - User Defined, Caught by default */
	/* 0x0A - User Defined, Caught by default */
	/* 0x0B - User Defined, Caught by default */
	/* 0x0C - User Defined, Caught by default */
	/* 0x0D - User Defined, Caught by default */
	/* 0x0E - User Defined, Caught by default */
	/* 0x0F - User Defined, Caught by default */
	/* 0x10 HW Single step, handled here */
	case VEC_STEP:
		info.si_code = TRAP_STEP;
		sig = SIGTRAP;
		CHK_DEBUGGER_TRAP_MAYBE();
		/* Check if this is a single step in kernel space */
		if (fp->ipend & 0xffc0)
			return;
		else
			break;
	/* 0x11 - Trace Buffer Full, handled here */
	case VEC_OVFLOW:
		info.si_code = TRAP_TRACEFLOW;
		sig = SIGTRAP;
		printk(KERN_NOTICE EXC_0x11(KERN_NOTICE));
		CHK_DEBUGGER_TRAP();
		break;
	/* 0x12 - Reserved, Caught by default */
	/* 0x13 - Reserved, Caught by default */
	/* 0x14 - Reserved, Caught by default */
	/* 0x15 - Reserved, Caught by default */
	/* 0x16 - Reserved, Caught by default */
	/* 0x17 - Reserved, Caught by default */
	/* 0x18 - Reserved, Caught by default */
	/* 0x19 - Reserved, Caught by default */
	/* 0x1A - Reserved, Caught by default */
	/* 0x1B - Reserved, Caught by default */
	/* 0x1C - Reserved, Caught by default */
	/* 0x1D - Reserved, Caught by default */
	/* 0x1E - Reserved, Caught by default */
	/* 0x1F - Reserved, Caught by default */
	/* 0x20 - Reserved, Caught by default */
	/* 0x21 - Undefined Instruction, handled here */
	case VEC_UNDEF_I:
		info.si_code = ILL_ILLOPC;
		sig = SIGILL;
		printk(KERN_NOTICE EXC_0x21(KERN_NOTICE));
		CHK_DEBUGGER_TRAP();
		break;
	/* 0x22 - Illegal Instruction Combination, handled here */
	case VEC_ILGAL_I:
		info.si_code = ILL_ILLPARAOP;
		sig = SIGILL;
		printk(KERN_NOTICE EXC_0x22(KERN_NOTICE));
		CHK_DEBUGGER_TRAP();
		break;
	/* 0x23 - Data CPLB protection violation, handled here */
	case VEC_CPLB_VL:
		info.si_code = ILL_CPLB_VI;
		sig = SIGBUS;
		printk(KERN_NOTICE EXC_0x23(KERN_NOTICE));
		CHK_DEBUGGER_TRAP();
		break;
	/* 0x24 - Data access misaligned, handled here */
	case VEC_MISALI_D:
		info.si_code = BUS_ADRALN;
		sig = SIGBUS;
		printk(KERN_NOTICE EXC_0x24(KERN_NOTICE));
		CHK_DEBUGGER_TRAP();
		break;
	/* 0x25 - Unrecoverable Event, handled here */
	case VEC_UNCOV:
		info.si_code = ILL_ILLEXCPT;
		sig = SIGILL;
		printk(KERN_NOTICE EXC_0x25(KERN_NOTICE));
		CHK_DEBUGGER_TRAP();
		break;
	/* 0x26 - Data CPLB Miss, normal case is handled in _cplb_hdr,
		error case is handled here */
	case VEC_CPLB_M:
		info.si_code = BUS_ADRALN;
		sig = SIGBUS;
		printk(KERN_NOTICE EXC_0x26(KERN_NOTICE));
		CHK_DEBUGGER_TRAP();
		break;
	/* 0x27 - Data CPLB Multiple Hits - Linux Trap Zero, handled here */
	case VEC_CPLB_MHIT:
		info.si_code = ILL_CPLB_MULHIT;
#ifdef CONFIG_DEBUG_HUNT_FOR_ZERO
		sig = SIGSEGV;
		printk(KERN_NOTICE "NULL pointer access (probably)\n");
#else
		sig = SIGILL;
		printk(KERN_NOTICE EXC_0x27(KERN_NOTICE));
#endif
		CHK_DEBUGGER_TRAP();
		break;
	/* 0x28 - Emulation Watchpoint, handled here */
	case VEC_WATCH:
		info.si_code = TRAP_WATCHPT;
		sig = SIGTRAP;
		pr_debug(EXC_0x28(KERN_DEBUG));
		CHK_DEBUGGER_TRAP_MAYBE();
		/* Check if this is a watchpoint in kernel space */
		if (fp->ipend & 0xffc0)
			return;
		else
			break;
#ifdef CONFIG_BF535
	/* 0x29 - Instruction fetch access error (535 only) */
	case VEC_ISTRU_VL:      /* ADSP-BF535 only (MH) */
		info.si_code = BUS_OPFETCH;
		sig = SIGBUS;
		printk(KERN_NOTICE "BF535: VEC_ISTRU_VL\n");
		CHK_DEBUGGER_TRAP();
		break;
#else
	/* 0x29 - Reserved, Caught by default */
#endif
	/* 0x2A - Instruction fetch misaligned, handled here */
	case VEC_MISALI_I:
		info.si_code = BUS_ADRALN;
		sig = SIGBUS;
		printk(KERN_NOTICE EXC_0x2A(KERN_NOTICE));
		CHK_DEBUGGER_TRAP();
		break;
	/* 0x2B - Instruction CPLB protection violation, handled here */
	case VEC_CPLB_I_VL:
		info.si_code = ILL_CPLB_VI;
		sig = SIGBUS;
		printk(KERN_NOTICE EXC_0x2B(KERN_NOTICE));
		CHK_DEBUGGER_TRAP();
		break;
	/* 0x2C - Instruction CPLB miss, handled in _cplb_hdr */
	case VEC_CPLB_I_M:
		info.si_code = ILL_CPLB_MISS;
		sig = SIGBUS;
		printk(KERN_NOTICE EXC_0x2C(KERN_NOTICE));
		CHK_DEBUGGER_TRAP();
		break;
	/* 0x2D - Instruction CPLB Multiple Hits, handled here */
	case VEC_CPLB_I_MHIT:
		info.si_code = ILL_CPLB_MULHIT;
#ifdef CONFIG_DEBUG_HUNT_FOR_ZERO
		sig = SIGSEGV;
		printk(KERN_NOTICE "Jump to address 0 - 0x0fff\n");
#else
		sig = SIGILL;
		printk(KERN_NOTICE EXC_0x2D(KERN_NOTICE));
#endif
		CHK_DEBUGGER_TRAP();
		break;
	/* 0x2E - Illegal use of Supervisor Resource, handled here */
	case VEC_ILL_RES:
		info.si_code = ILL_PRVOPC;
		sig = SIGILL;
		printk(KERN_NOTICE EXC_0x2E(KERN_NOTICE));
		CHK_DEBUGGER_TRAP();
		break;
	/* 0x2F - Reserved, Caught by default */
	/* 0x30 - Reserved, Caught by default */
	/* 0x31 - Reserved, Caught by default */
	/* 0x32 - Reserved, Caught by default */
	/* 0x33 - Reserved, Caught by default */
	/* 0x34 - Reserved, Caught by default */
	/* 0x35 - Reserved, Caught by default */
	/* 0x36 - Reserved, Caught by default */
	/* 0x37 - Reserved, Caught by default */
	/* 0x38 - Reserved, Caught by default */
	/* 0x39 - Reserved, Caught by default */
	/* 0x3A - Reserved, Caught by default */
	/* 0x3B - Reserved, Caught by default */
	/* 0x3C - Reserved, Caught by default */
	/* 0x3D - Reserved, Caught by default */
	/* 0x3E - Reserved, Caught by default */
	/* 0x3F - Reserved, Caught by default */
	case VEC_HWERR:
		info.si_code = BUS_ADRALN;
		sig = SIGBUS;
		switch (fp->seqstat & SEQSTAT_HWERRCAUSE) {
		/* System MMR Error */
		case (SEQSTAT_HWERRCAUSE_SYSTEM_MMR):
			info.si_code = BUS_ADRALN;
			sig = SIGBUS;
			printk(KERN_NOTICE HWC_x2(KERN_NOTICE));
			break;
		/* External Memory Addressing Error */
		case (SEQSTAT_HWERRCAUSE_EXTERN_ADDR):
			info.si_code = BUS_ADRERR;
			sig = SIGBUS;
			printk(KERN_NOTICE HWC_x3(KERN_NOTICE));
			break;
		/* Performance Monitor Overflow */
		case (SEQSTAT_HWERRCAUSE_PERF_FLOW):
			printk(KERN_NOTICE HWC_x12(KERN_NOTICE));
			break;
		/* RAISE 5 instruction */
		case (SEQSTAT_HWERRCAUSE_RAISE_5):
			printk(KERN_NOTICE HWC_x18(KERN_NOTICE));
			break;
		default:        /* Reserved */
			printk(KERN_NOTICE HWC_default(KERN_NOTICE));
			break;
		}
		CHK_DEBUGGER_TRAP();
		break;
	default:
		info.si_code = TRAP_ILLTRAP;
		sig = SIGTRAP;
		printk(KERN_EMERG "Caught Unhandled Exception, code = %08lx\n",
			(fp->seqstat & SEQSTAT_EXCAUSE));
		CHK_DEBUGGER_TRAP();
		break;
	}

	BUG_ON(sig == 0);

	if (sig != SIGTRAP) {
		unsigned long stack;
		dump_bfin_process(fp);
		dump_bfin_mem(fp);
		show_regs(fp);

		/* Print out the trace buffer if it makes sense */
#ifndef CONFIG_DEBUG_BFIN_NO_KERN_HWTRACE
		if (trapnr == VEC_CPLB_I_M || trapnr == VEC_CPLB_M)
			printk(KERN_NOTICE "No trace since you do not have "
				"CONFIG_DEBUG_BFIN_NO_KERN_HWTRACE enabled\n"
				KERN_NOTICE "\n");
		else
#endif
			dump_bfin_trace_buffer();
		show_stack(current, &stack);
		if (oops_in_progress) {
			print_modules();
#ifndef CONFIG_ACCESS_CHECK
			printk(KERN_EMERG "Please turn on "
			       "CONFIG_ACCESS_CHECK\n");
#endif
			panic("Kernel exception");
		}
	}

	info.si_signo = sig;
	info.si_errno = 0;
	info.si_addr = (void __user *)fp->pc;
	force_sig_info(sig, &info, current);

	trace_buffer_restore(j);
	return;
}

/* Typical exception handling routines	*/

#define EXPAND_LEN ((1 << CONFIG_DEBUG_BFIN_HWTRACE_EXPAND_LEN) * 256 - 1)

void dump_bfin_trace_buffer(void)
{
#ifdef CONFIG_DEBUG_BFIN_HWTRACE_ON
	int tflags, i = 0;
	char buf[150];
#ifdef CONFIG_DEBUG_BFIN_HWTRACE_EXPAND
	int j, index;
#endif

	trace_buffer_save(tflags);

	printk(KERN_NOTICE "Hardware Trace:\n");

	if (likely(bfin_read_TBUFSTAT() & TBUFCNT)) {
		for (; bfin_read_TBUFSTAT() & TBUFCNT; i++) {
			decode_address(buf, (unsigned long)bfin_read_TBUF());
			printk(KERN_NOTICE "%4i Target : %s\n", i, buf);
			decode_address(buf, (unsigned long)bfin_read_TBUF());
			printk(KERN_NOTICE "     Source : %s\n", buf);
		}
	}

#ifdef CONFIG_DEBUG_BFIN_HWTRACE_EXPAND
	if (trace_buff_offset)
		index = trace_buff_offset/4 - 1;
	else
		index = EXPAND_LEN;

	j = (1 << CONFIG_DEBUG_BFIN_HWTRACE_EXPAND_LEN) * 128;
	while (j) {
		decode_address(buf, software_trace_buff[index]);
		printk(KERN_NOTICE "%4i Target : %s\n", i, buf);
		index -= 1;
		if (index < 0 )
			index = EXPAND_LEN;
		decode_address(buf, software_trace_buff[index]);
		printk(KERN_NOTICE "     Source : %s\n", buf);
		index -= 1;
		if (index < 0)
			index = EXPAND_LEN;
		j--;
		i++;
	}
#endif

	trace_buffer_restore(tflags);
#endif
}
EXPORT_SYMBOL(dump_bfin_trace_buffer);

static void show_trace(struct task_struct *tsk, unsigned long *sp)
{
	unsigned long addr;

	printk(KERN_NOTICE "\n" KERN_NOTICE "Call Trace:\n");

	while (!kstack_end(sp)) {
		addr = *sp++;
		/*
		 * If the address is either in the text segment of the
		 * kernel, or in the region which contains vmalloc'ed
		 * memory, it *may* be the address of a calling
		 * routine; if so, print it so that someone tracing
		 * down the cause of the crash will be able to figure
		 * out the call path that was taken.
		 */
		if (kernel_text_address(addr))
			print_ip_sym(addr);
	}

	printk(KERN_NOTICE "\n");
}

void show_stack(struct task_struct *task, unsigned long *stack)
{
	unsigned long *endstack, addr;
	int i;

	/* Cannot call dump_bfin_trace_buffer() here as show_stack() is
	 * called externally in some places in the kernel.
	 */

	if (!stack) {
		if (task)
			stack = (unsigned long *)task->thread.ksp;
		else
			stack = (unsigned long *)&stack;
	}

	addr = (unsigned long)stack;
	endstack = (unsigned long *)PAGE_ALIGN(addr);

	printk(KERN_NOTICE "Stack from %08lx:", (unsigned long)stack);
	for (i = 0; i < kstack_depth_to_print; i++) {
		if (stack + 1 > endstack)
			break;
		if (i % 8 == 0)
			printk("\n" KERN_NOTICE "       ");
		printk(" %08lx", *stack++);
	}
	printk("\n");

	show_trace(task, stack);
}

void dump_stack(void)
{
	unsigned long stack;
#ifdef CONFIG_DEBUG_BFIN_HWTRACE_ON
	int tflags;
#endif
	trace_buffer_save(tflags);
	dump_bfin_trace_buffer();
	show_stack(current, &stack);
	trace_buffer_restore(tflags);
}
EXPORT_SYMBOL(dump_stack);

void dump_bfin_process(struct pt_regs *fp)
{
	/* We should be able to look at fp->ipend, but we don't push it on the
	 * stack all the time, so do this until we fix that */
	unsigned int context = bfin_read_IPEND();

	if (oops_in_progress)
		printk(KERN_EMERG "Kernel OOPS in progress\n");

	if (context & 0x0020 && (fp->seqstat & SEQSTAT_EXCAUSE) == VEC_HWERR)
		printk(KERN_NOTICE "HW Error context\n");
	else if (context & 0x0020)
		printk(KERN_NOTICE "Deferred Exception context\n");
	else if (context & 0x3FC0)
		printk(KERN_NOTICE "Interrupt context\n");
	else if (context & 0x4000)
		printk(KERN_NOTICE "Deferred Interrupt context\n");
	else if (context & 0x8000)
		printk(KERN_NOTICE "Kernel process context\n");

	/* Because we are crashing, and pointers could be bad, we check things
	 * pretty closely before we use them
	 */
	if ((unsigned long)current >= FIXED_CODE_START &&
	    !((unsigned long)current & 0x3) && current->pid) {
		printk(KERN_NOTICE "CURRENT PROCESS:\n");
		if (current->comm >= (char *)FIXED_CODE_START)
			printk(KERN_NOTICE "COMM=%s PID=%d\n",
				current->comm, current->pid);
		else
			printk(KERN_NOTICE "COMM= invalid\n");

		if (!((unsigned long)current->mm & 0x3) && (unsigned long)current->mm >= FIXED_CODE_START)
			printk(KERN_NOTICE  "TEXT = 0x%p-0x%p        DATA = 0x%p-0x%p\n"
				KERN_NOTICE " BSS = 0x%p-0x%p  USER-STACK = 0x%p\n"
				KERN_NOTICE "\n",
				(void *)current->mm->start_code,
				(void *)current->mm->end_code,
				(void *)current->mm->start_data,
				(void *)current->mm->end_data,
				(void *)current->mm->end_data,
				(void *)current->mm->brk,
				(void *)current->mm->start_stack);
		else
			printk(KERN_NOTICE "invalid mm\n");
	} else
		printk(KERN_NOTICE "\n" KERN_NOTICE
		     "No Valid process in current context\n");
}

void dump_bfin_mem(struct pt_regs *fp)
{
	unsigned short *addr, *erraddr, val = 0, err = 0;
	char sti = 0, buf[6];

	if (unlikely((fp->seqstat & SEQSTAT_EXCAUSE) == VEC_HWERR))
		erraddr = (void *)fp->pc;
	else
		erraddr = (void *)fp->retx;

	printk(KERN_NOTICE "return address: [0x%p]; contents of:", erraddr);

	for (addr = (unsigned short *)((unsigned long)erraddr & ~0xF) - 0x10;
	     addr < (unsigned short *)((unsigned long)erraddr & ~0xF) + 0x10;
	     addr++) {
		if (!((unsigned long)addr & 0xF))
			printk("\n" KERN_NOTICE "0x%p: ", addr);

		if (get_user(val, addr)) {
			if (addr >= (unsigned short *)L1_CODE_START &&
			    addr < (unsigned short *)(L1_CODE_START + L1_CODE_LENGTH)) {
				dma_memcpy(&val, addr, sizeof(val));
				sprintf(buf, "%04x", val);
			} else if (addr >= (unsigned short *)FIXED_CODE_START &&
				addr <= (unsigned short *)memory_start) {
				val = bfin_read16(addr);
				sprintf(buf, "%04x", val);
			} else {
				val = 0;
				sprintf(buf, "????");
			}
		} else
			sprintf(buf, "%04x", val);

		if (addr == erraddr) {
			printk("[%s]", buf);
			err = val;
		} else
			printk(" %s ", buf);

		/* Do any previous instructions turn on interrupts? */
		if (addr <= erraddr &&				/* in the past */
		    ((val >= 0x0040 && val <= 0x0047) ||	/* STI instruction */
		      val == 0x017b))				/* [SP++] = RETI */
			sti = 1;
	}

	printk("\n");

	/* Hardware error interrupts can be deferred */
	if (unlikely(sti && (fp->seqstat & SEQSTAT_EXCAUSE) == VEC_HWERR &&
	    oops_in_progress)){
		printk(KERN_NOTICE "Looks like this was a deferred error - sorry\n");
#ifndef CONFIG_DEBUG_HWERR
		printk(KERN_NOTICE "The remaining message may be meaningless\n"
			KERN_NOTICE "You should enable CONFIG_DEBUG_HWERR to get a"
			 " better idea where it came from\n");
#else
		/* If we are handling only one peripheral interrupt
		 * and current mm and pid are valid, and the last error
		 * was in that user space process's text area
		 * print it out - because that is where the problem exists
		 */
		if ((!(((fp)->ipend & ~0x30) & (((fp)->ipend & ~0x30) - 1))) &&
		     (current->pid && current->mm)) {
			/* And the last RETI points to the current userspace context */
			if ((fp + 1)->pc >= current->mm->start_code &&
			    (fp + 1)->pc <= current->mm->end_code) {
				printk(KERN_NOTICE "It might be better to look around here : \n");
				printk(KERN_NOTICE "-------------------------------------------\n");
				show_regs(fp + 1);
				printk(KERN_NOTICE "-------------------------------------------\n");
			}
		}
#endif
	}
}

void show_regs(struct pt_regs *fp)
{
	char buf [150];
	struct irqaction *action;
	unsigned int i;
	unsigned long flags;

	printk(KERN_NOTICE "\n" KERN_NOTICE "SEQUENCER STATUS:\t\t%s\n", print_tainted());
	printk(KERN_NOTICE " SEQSTAT: %08lx  IPEND: %04lx  SYSCFG: %04lx\n",
		(long)fp->seqstat, fp->ipend, fp->syscfg);
	printk(KERN_NOTICE "  HWERRCAUSE: 0x%lx\n",
		(fp->seqstat & SEQSTAT_HWERRCAUSE) >> 14);
	printk(KERN_NOTICE "  EXCAUSE   : 0x%lx\n",
		fp->seqstat & SEQSTAT_EXCAUSE);
	for (i = 6; i <= 15 ; i++) {
		if (fp->ipend & (1 << i)) {
			decode_address(buf, bfin_read32(EVT0 + 4*i));
			printk(KERN_NOTICE "  physical IVG%i asserted : %s\n", i, buf);
		}
	}

	/* if no interrupts are going off, don't print this out */
	if (fp->ipend & ~0x3F) {
		for (i = 0; i < (NR_IRQS - 1); i++) {
			spin_lock_irqsave(&irq_desc[i].lock, flags);
			action = irq_desc[i].action;
			if (!action)
				goto unlock;

			decode_address(buf, (unsigned int)action->handler);
			printk(KERN_NOTICE "  logical irq %3d mapped  : %s", i, buf);
			for (action = action->next; action; action = action->next) {
				decode_address(buf, (unsigned int)action->handler);
				printk(", %s", buf);
			}
			printk("\n");
unlock:
			spin_unlock_irqrestore(&irq_desc[i].lock, flags);
		}
	}

	decode_address(buf, fp->rete);
	printk(KERN_NOTICE " RETE: %s\n", buf);
	decode_address(buf, fp->retn);
	printk(KERN_NOTICE " RETN: %s\n", buf);
	decode_address(buf, fp->retx);
	printk(KERN_NOTICE " RETX: %s\n", buf);
	decode_address(buf, fp->rets);
	printk(KERN_NOTICE " RETS: %s\n", buf);
	decode_address(buf, fp->pc);
	printk(KERN_NOTICE " PC  : %s\n", buf);

	if (((long)fp->seqstat &  SEQSTAT_EXCAUSE) &&
	    (((long)fp->seqstat & SEQSTAT_EXCAUSE) != VEC_HWERR)) {
		decode_address(buf, bfin_read_DCPLB_FAULT_ADDR());
		printk(KERN_NOTICE "DCPLB_FAULT_ADDR: %s\n", buf);
		decode_address(buf, bfin_read_ICPLB_FAULT_ADDR());
		printk(KERN_NOTICE "ICPLB_FAULT_ADDR: %s\n", buf);
	}

	printk(KERN_NOTICE "\n" KERN_NOTICE "PROCESSOR STATE:\n");
	printk(KERN_NOTICE " R0 : %08lx    R1 : %08lx    R2 : %08lx    R3 : %08lx\n",
		fp->r0, fp->r1, fp->r2, fp->r3);
	printk(KERN_NOTICE " R4 : %08lx    R5 : %08lx    R6 : %08lx    R7 : %08lx\n",
		fp->r4, fp->r5, fp->r6, fp->r7);
	printk(KERN_NOTICE " P0 : %08lx    P1 : %08lx    P2 : %08lx    P3 : %08lx\n",
		fp->p0, fp->p1, fp->p2, fp->p3);
	printk(KERN_NOTICE " P4 : %08lx    P5 : %08lx    FP : %08lx    SP : %08lx\n",
		fp->p4, fp->p5, fp->fp, (long)fp);
	printk(KERN_NOTICE " LB0: %08lx    LT0: %08lx    LC0: %08lx\n",
		fp->lb0, fp->lt0, fp->lc0);
	printk(KERN_NOTICE " LB1: %08lx    LT1: %08lx    LC1: %08lx\n",
		fp->lb1, fp->lt1, fp->lc1);
	printk(KERN_NOTICE " B0 : %08lx    L0 : %08lx    M0 : %08lx    I0 : %08lx\n",
		fp->b0, fp->l0, fp->m0, fp->i0);
	printk(KERN_NOTICE " B1 : %08lx    L1 : %08lx    M1 : %08lx    I1 : %08lx\n",
		fp->b1, fp->l1, fp->m1, fp->i1);
	printk(KERN_NOTICE " B2 : %08lx    L2 : %08lx    M2 : %08lx    I2 : %08lx\n",
		fp->b2, fp->l2, fp->m2, fp->i2);
	printk(KERN_NOTICE " B3 : %08lx    L3 : %08lx    M3 : %08lx    I3 : %08lx\n",
		fp->b3, fp->l3, fp->m3, fp->i3);
	printk(KERN_NOTICE "A0.w: %08lx   A0.x: %08lx   A1.w: %08lx   A1.x: %08lx\n",
		fp->a0w, fp->a0x, fp->a1w, fp->a1x);

	printk(KERN_NOTICE "USP : %08lx  ASTAT: %08lx\n",
		rdusp(), fp->astat);

	printk(KERN_NOTICE "\n");
}

#ifdef CONFIG_SYS_BFIN_SPINLOCK_L1
asmlinkage int sys_bfin_spinlock(int *spinlock)__attribute__((l1_text));
#endif

asmlinkage int sys_bfin_spinlock(int *spinlock)
{
	int ret = 0;
	int tmp = 0;

	local_irq_disable();
	ret = get_user(tmp, spinlock);
	if (ret == 0) {
		if (tmp)
			ret = 1;
		tmp = 1;
		put_user(tmp, spinlock);
	}
	local_irq_enable();
	return ret;
}

int bfin_request_exception(unsigned int exception, void (*handler)(void))
{
	void (*curr_handler)(void);

	if (exception > 0x3F)
		return -EINVAL;

	curr_handler = ex_table[exception];

	if (curr_handler != ex_replaceable)
		return -EBUSY;

	ex_table[exception] = handler;

	return 0;
}
EXPORT_SYMBOL(bfin_request_exception);

int bfin_free_exception(unsigned int exception, void (*handler)(void))
{
	void (*curr_handler)(void);

	if (exception > 0x3F)
		return -EINVAL;

	curr_handler = ex_table[exception];

	if (curr_handler != handler)
		return -EBUSY;

	ex_table[exception] = ex_replaceable;

	return 0;
}
EXPORT_SYMBOL(bfin_free_exception);

void panic_cplb_error(int cplb_panic, struct pt_regs *fp)
{
	switch (cplb_panic) {
	case CPLB_NO_UNLOCKED:
		printk(KERN_EMERG "All CPLBs are locked\n");
		break;
	case CPLB_PROT_VIOL:
		return;
	case CPLB_NO_ADDR_MATCH:
		return;
	case CPLB_UNKNOWN_ERR:
		printk(KERN_EMERG "Unknown CPLB Exception\n");
		break;
	}

	oops_in_progress = 1;

	printk(KERN_EMERG "DCPLB_FAULT_ADDR=%p\n", (void *)bfin_read_DCPLB_FAULT_ADDR());
	printk(KERN_EMERG "ICPLB_FAULT_ADDR=%p\n", (void *)bfin_read_ICPLB_FAULT_ADDR());
	dump_bfin_process(fp);
	dump_bfin_mem(fp);
	show_regs(fp);
	dump_stack();
	panic("Unrecoverable event\n");
}