summaryrefslogtreecommitdiff
path: root/arch/blackfin/mach-common/entry.S
blob: 1c3d2c5bb0bb873fcec8f65eb48379279e479c65 (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
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
1043
1044
1045
1046
1047
1048
1049
1050
1051
1052
1053
1054
1055
1056
1057
1058
1059
1060
1061
1062
1063
1064
1065
1066
1067
1068
1069
1070
1071
1072
1073
1074
1075
1076
1077
1078
1079
1080
1081
1082
1083
1084
1085
1086
1087
1088
1089
1090
1091
1092
1093
1094
1095
1096
1097
1098
1099
1100
1101
1102
1103
1104
1105
1106
1107
1108
1109
1110
1111
1112
1113
1114
1115
1116
1117
1118
1119
1120
1121
1122
1123
1124
1125
1126
1127
1128
1129
1130
1131
1132
1133
1134
1135
1136
1137
1138
1139
1140
1141
1142
1143
1144
1145
1146
1147
1148
1149
1150
1151
1152
1153
1154
1155
1156
1157
1158
1159
1160
1161
1162
1163
1164
1165
1166
1167
1168
1169
1170
1171
1172
1173
1174
1175
1176
1177
1178
1179
1180
1181
1182
1183
1184
1185
1186
1187
1188
1189
1190
1191
1192
1193
1194
1195
1196
1197
1198
1199
1200
1201
1202
1203
1204
1205
1206
1207
1208
1209
1210
1211
1212
1213
1214
1215
1216
1217
1218
1219
1220
1221
1222
1223
1224
1225
1226
1227
1228
1229
1230
1231
1232
1233
1234
1235
1236
1237
1238
1239
1240
1241
1242
1243
1244
1245
1246
1247
1248
1249
1250
1251
1252
1253
1254
1255
1256
1257
1258
1259
1260
1261
1262
1263
1264
1265
1266
1267
1268
1269
1270
1271
1272
1273
1274
1275
1276
1277
1278
1279
1280
1281
1282
1283
1284
1285
1286
1287
1288
1289
1290
1291
1292
1293
1294
1295
1296
1297
1298
1299
1300
1301
1302
1303
1304
1305
1306
1307
1308
1309
1310
1311
1312
1313
1314
1315
1316
1317
1318
1319
1320
1321
1322
1323
1324
1325
1326
1327
1328
1329
1330
1331
1332
1333
1334
1335
1336
1337
1338
1339
1340
1341
1342
1343
1344
1345
1346
1347
1348
1349
1350
1351
1352
1353
1354
1355
1356
1357
1358
1359
1360
1361
1362
1363
1364
1365
1366
1367
1368
1369
1370
1371
1372
1373
1374
1375
1376
1377
1378
1379
1380
1381
1382
1383
1384
1385
1386
1387
1388
1389
1390
1391
1392
1393
1394
1395
1396
1397
1398
1399
1400
1401
1402
1403
1404
1405
1406
1407
1408
1409
1410
1411
1412
1413
1414
1415
1416
1417
1418
1419
1420
1421
1422
1423
1424
1425
1426
1427
1428
1429
1430
1431
1432
1433
1434
1435
1436
1437
1438
1439
1440
1441
1442
1443
1444
1445
1446
1447
1448
1449
1450
1451
1452
1453
1454
1455
1456
1457
1458
1459
1460
1461
1462
1463
1464
1465
1466
1467
1468
1469
1470
1471
1472
1473
1474
1475
1476
1477
1478
1479
1480
1481
1482
1483
1484
1485
1486
1487
1488
1489
1490
1491
1492
1493
1494
1495
1496
1497
1498
1499
1500
1501
1502
1503
1504
1505
1506
1507
1508
1509
1510
1511
1512
1513
1514
1515
1516
1517
1518
1519
1520
1521
1522
1523
1524
1525
1526
1527
1528
1529
1530
1531
1532
1533
1534
1535
1536
1537
1538
1539
1540
1541
1542
1543
1544
1545
1546
1547
1548
1549
1550
1551
1552
1553
1554
1555
1556
1557
1558
1559
1560
1561
1562
1563
1564
1565
1566
1567
1568
1569
1570
1571
1572
1573
1574
1575
1576
1577
1578
1579
1580
1581
1582
1583
1584
1585
1586
1587
1588
1589
1590
1591
1592
1593
1594
1595
1596
1597
1598
1599
1600
1601
1602
1603
1604
1605
1606
1607
1608
1609
1610
1611
1612
1613
1614
1615
1616
1617
1618
1619
1620
1621
1622
1623
1624
1625
1626
1627
1628
1629
1630
1631
1632
1633
1634
1635
1636
1637
1638
1639
1640
1641
1642
1643
1644
1645
1646
1647
1648
1649
1650
1651
1652
1653
1654
1655
1656
1657
1658
1659
1660
1661
1662
1663
1664
1665
1666
1667
1668
1669
1670
1671
1672
1673
1674
1675
1676
1677
1678
1679
1680
1681
1682
1683
1684
1685
1686
1687
1688
1689
1690
1691
1692
1693
1694
1695
1696
1697
1698
1699
1700
1701
1702
1703
1704
1705
1706
1707
1708
1709
1710
1711
1712
1713
1714
1715
1716
1717
1718
1719
1720
1721
1722
1723
1724
1725
1726
1727
1728
1729
1730
1731
1732
1733
1734
1735
1736
1737
1738
1739
1740
1741
1742
1743
1744
1745
1746
1747
1748
1749
1750
1751
1752
1753
1754
1755
1756
/*
 * Contains the system-call and fault low-level handling routines.
 * This also contains the timer-interrupt handler, as well as all
 * interrupts and faults that can result in a task-switch.
 *
 * Copyright 2005-2009 Analog Devices Inc.
 *
 * Licensed under the GPL-2 or later.
 */

/* NOTE: This code handles signal-recognition, which happens every time
 * after a timer-interrupt and after each system call.
 */

#include <linux/init.h>
#include <linux/linkage.h>
#include <linux/unistd.h>
#include <asm/blackfin.h>
#include <asm/errno.h>
#include <asm/fixed_code.h>
#include <asm/thread_info.h>  /* TIF_NEED_RESCHED */
#include <asm/asm-offsets.h>
#include <asm/trace.h>
#include <asm/traps.h>

#include <asm/context.S>


#ifdef CONFIG_EXCPT_IRQ_SYSC_L1
.section .l1.text
#else
.text
#endif

/* Slightly simplified and streamlined entry point for CPLB misses.
 * This one does not lower the level to IRQ5, and thus can be used to
 * patch up CPLB misses on the kernel stack.
 */
#if ANOMALY_05000261
#define _ex_dviol _ex_workaround_261
#define _ex_dmiss _ex_workaround_261
#define _ex_dmult _ex_workaround_261

ENTRY(_ex_workaround_261)
	/*
	 * Work around an anomaly: if we see a new DCPLB fault, return
	 * without doing anything.  Then, if we get the same fault again,
	 * handle it.
	 */
	P4 = R7;	/* Store EXCAUSE */

	GET_PDA(p5, r7);
	r7 = [p5 + PDA_LFRETX];
	r6 = retx;
	[p5 + PDA_LFRETX] = r6;
	cc = r6 == r7;
	if !cc jump _bfin_return_from_exception;
	/* fall through */
	R7 = P4;
	R6 = VEC_CPLB_M;	/* Data CPLB Miss */
	cc = R6 == R7;
	if cc jump _ex_dcplb_miss (BP);
#ifdef CONFIG_MPU
	R6 = VEC_CPLB_VL;	/* Data CPLB Violation */
	cc = R6 == R7;
	if cc jump _ex_dcplb_viol (BP);
#endif
	/* Handle Data CPLB Protection Violation
	 * and Data CPLB Multiple Hits - Linux Trap Zero
	 */
	jump _ex_trap_c;
ENDPROC(_ex_workaround_261)

#else
#ifdef CONFIG_MPU
#define _ex_dviol _ex_dcplb_viol
#else
#define _ex_dviol _ex_trap_c
#endif
#define _ex_dmiss _ex_dcplb_miss
#define _ex_dmult _ex_trap_c
#endif


ENTRY(_ex_dcplb_viol)
ENTRY(_ex_dcplb_miss)
ENTRY(_ex_icplb_miss)
	(R7:6,P5:4) = [sp++];
	/* We leave the previously pushed ASTAT on the stack.  */
	SAVE_CONTEXT_CPLB

	/* We must load R1 here, _before_ DEBUG_HWTRACE_SAVE, since that
	 * will change the stack pointer.  */
	R0 = SEQSTAT;
	R1 = SP;

	DEBUG_HWTRACE_SAVE(p5, r7)

	sp += -12;
	call _cplb_hdr;
	sp += 12;
	CC = R0 == 0;
	IF !CC JUMP _handle_bad_cplb;

#ifdef CONFIG_DEBUG_DOUBLEFAULT
	/* While we were processing this, did we double fault? */
	r7 = SEQSTAT;           /* reason code is in bit 5:0 */
	r6.l = lo(SEQSTAT_EXCAUSE);
	r6.h = hi(SEQSTAT_EXCAUSE);
	r7 = r7 & r6;
	r6 = 0x25;
	CC = R7 == R6;
	if CC JUMP _double_fault;
#endif

	DEBUG_HWTRACE_RESTORE(p5, r7)
	RESTORE_CONTEXT_CPLB
	ASTAT = [SP++];
	SP = EX_SCRATCH_REG;
	rtx;
ENDPROC(_ex_icplb_miss)

ENTRY(_ex_syscall)
	raise 15;		/* invoked by TRAP #0, for sys call */
	jump.s _bfin_return_from_exception;
ENDPROC(_ex_syscall)

ENTRY(_ex_single_step)
	/* If we just returned from an interrupt, the single step event is
	   for the RTI instruction.  */
	r7 = retx;
	r6 = reti;
	cc = r7 == r6;
	if cc jump _bfin_return_from_exception;

#ifdef CONFIG_KGDB
	/* Don't do single step in hardware exception handler */
        p5.l = lo(IPEND);
        p5.h = hi(IPEND);
	r6 = [p5];
	cc = bittst(r6, 4);
	if cc jump _bfin_return_from_exception;
	cc = bittst(r6, 5);
	if cc jump _bfin_return_from_exception;

	/* skip single step if current interrupt priority is higher than
	 * that of the first instruction, from which gdb starts single step */
	r6 >>= 6;
	r7 = 10;
.Lfind_priority_start:
	cc = bittst(r6, 0);
	if cc jump .Lfind_priority_done;
	r6 >>= 1;
	r7 += -1;
	cc = r7 == 0;
	if cc jump .Lfind_priority_done;
	jump.s .Lfind_priority_start;
.Lfind_priority_done:
	p4.l = _kgdb_single_step;
	p4.h = _kgdb_single_step;
	r6 = [p4];
	cc = r6 == 0;
	if cc jump .Ldo_single_step;
	r6 += -1;
	cc = r6 < r7;
	if cc jump 1f;
.Ldo_single_step:
#else
	/* If we were in user mode, do the single step normally.  */
	p5.l = lo(IPEND);
	p5.h = hi(IPEND);
	r6 = [p5];
	r7 = 0xffe0 (z);
	r7 = r7 & r6;
	cc = r7 == 0;
	if !cc jump 1f;
#endif
#ifdef CONFIG_EXACT_HWERR
	/* Read the ILAT, and to check to see if the process we are
	 * single stepping caused a previous hardware error
	 * If so, do not single step, (which lowers to IRQ5, and makes
	 * us miss the error).
	 */
	p5.l = lo(ILAT);
	p5.h = hi(ILAT);
	r7 = [p5];
	cc = bittst(r7, EVT_IVHW_P);
	if cc jump 1f;
#endif
	/* Single stepping only a single instruction, so clear the trace
	 * bit here.  */
	r7 = syscfg;
	bitclr (r7, SYSCFG_SSSTEP_P);
	syscfg = R7;
	jump _ex_trap_c;

1:
	/*
	 * We were in an interrupt handler.  By convention, all of them save
	 * SYSCFG with their first instruction, so by checking whether our
	 * RETX points at the entry point, we can determine whether to allow
	 * a single step, or whether to clear SYSCFG.
	 *
	 * First, find out the interrupt level and the event vector for it.
	 */
	p5.l = lo(EVT0);
	p5.h = hi(EVT0);
	p5 += -4;
2:
	r7 = rot r7 by -1;
	p5 += 4;
	if !cc jump 2b;

	/* What we actually do is test for the _second_ instruction in the
	 * IRQ handler.  That way, if there are insns following the restore
	 * of SYSCFG after leaving the handler, we will not turn off SYSCFG
	 * for them.  */

	r7 = [p5];
	r7 += 2;
	r6 = RETX;
	cc = R7 == R6;
	if !cc jump _bfin_return_from_exception;

	r7 = syscfg;
	bitclr (r7, SYSCFG_SSSTEP_P);	/* Turn off single step */
	syscfg = R7;

	/* Fall through to _bfin_return_from_exception.  */
ENDPROC(_ex_single_step)

ENTRY(_bfin_return_from_exception)
#if ANOMALY_05000257
	R7=LC0;
	LC0=R7;
	R7=LC1;
	LC1=R7;
#endif

#ifdef CONFIG_DEBUG_DOUBLEFAULT
	/* While we were processing the current exception,
	 * did we cause another, and double fault?
	 */
	r7 = SEQSTAT;           /* reason code is in bit 5:0 */
	r6.l = lo(SEQSTAT_EXCAUSE);
	r6.h = hi(SEQSTAT_EXCAUSE);
	r7 = r7 & r6;
	r6 = VEC_UNCOV;
	CC = R7 == R6;
	if CC JUMP _double_fault;
#endif

	(R7:6,P5:4) = [sp++];
	ASTAT = [sp++];
	sp = EX_SCRATCH_REG;
	rtx;
ENDPROC(_bfin_return_from_exception)

ENTRY(_handle_bad_cplb)
	DEBUG_HWTRACE_RESTORE(p5, r7)
	/* To get here, we just tried and failed to change a CPLB
	 * so, handle things in trap_c (C code), by lowering to
	 * IRQ5, just like we normally do. Since this is not a
	 * "normal" return path, we have a do a lot of stuff to
	 * the stack to get ready so, we can fall through - we
	 * need to make a CPLB exception look like a normal exception
	 */
	RESTORE_CONTEXT_CPLB
	/* ASTAT is still on the stack, where it is needed.  */
	[--sp] = (R7:6,P5:4);

ENTRY(_ex_replaceable)
	nop;

ENTRY(_ex_trap_c)
	/* The only thing that has been saved in this context is
	 * (R7:6,P5:4), ASTAT & SP - don't use anything else
	 */

	GET_PDA(p5, r6);

	/* Make sure we are not in a double fault */
	p4.l = lo(IPEND);
	p4.h = hi(IPEND);
	r7 = [p4];
	CC = BITTST (r7, 5);
	if CC jump _double_fault;
	[p5 + PDA_EXIPEND] = r7;

	/* Call C code (trap_c) to handle the exception, which most
	 * likely involves sending a signal to the current process.
	 * To avoid double faults, lower our priority to IRQ5 first.
	 */
	r7.h = _exception_to_level5;
	r7.l = _exception_to_level5;
	p4.l = lo(EVT5);
	p4.h = hi(EVT5);
	[p4] = r7;
	csync;

	/*
	 * Save these registers, as they are only valid in exception context
	 *  (where we are now - as soon as we defer to IRQ5, they can change)
	 * DCPLB_STATUS and ICPLB_STATUS are also only valid in EVT3,
	 * but they are not very interesting, so don't save them
	 */

	p4.l = lo(DCPLB_FAULT_ADDR);
	p4.h = hi(DCPLB_FAULT_ADDR);
	r7 = [p4];
	[p5 + PDA_DCPLB] = r7;

	p4.l = lo(ICPLB_FAULT_ADDR);
	p4.h = hi(ICPLB_FAULT_ADDR);
	r6 = [p4];
	[p5 + PDA_ICPLB] = r6;

	r6 = retx;
	[p5 + PDA_RETX] = r6;

	r6 = SEQSTAT;
	[p5 + PDA_SEQSTAT] = r6;

	/* Save the state of single stepping */
	r6 = SYSCFG;
	[p5 + PDA_SYSCFG] = r6;
	/* Clear it while we handle the exception in IRQ5 mode */
	BITCLR(r6, SYSCFG_SSSTEP_P);
	SYSCFG = r6;

	/* Save the current IMASK, since we change in order to jump to level 5 */
	cli r6;
	[p5 + PDA_EXIMASK] = r6;

	p4.l = lo(SAFE_USER_INSTRUCTION);
	p4.h = hi(SAFE_USER_INSTRUCTION);
	retx = p4;

	/* Disable all interrupts, but make sure level 5 is enabled so
	 * we can switch to that level.
	 */
	r6 = 0x3f;
	sti r6;

	/* In case interrupts are disabled IPEND[4] (global interrupt disable bit)
	 * clear it (re-enabling interrupts again) by the special sequence of pushing
	 * RETI onto the stack.  This way we can lower ourselves to IVG5 even if the
	 * exception was taken after the interrupt handler was called but before it
	 * got a chance to enable global interrupts itself.
	 */
	[--sp] = reti;
	sp += 4;

	raise 5;
	jump.s _bfin_return_from_exception;
ENDPROC(_ex_trap_c)

/* We just realized we got an exception, while we were processing a different
 * exception. This is a unrecoverable event, so crash.
 * Note: this cannot be ENTRY() as we jump here with "if cc jump" ...
 */
ENTRY(_double_fault)
	/* Turn caches & protection off, to ensure we don't get any more
	 * double exceptions
	 */

	P4.L = LO(IMEM_CONTROL);
	P4.H = HI(IMEM_CONTROL);

	R5 = [P4];              /* Control Register*/
	BITCLR(R5,ENICPLB_P);
	CSYNC;          /* Disabling of CPLBs should be proceeded by a CSYNC */
	[P4] = R5;
	SSYNC;

	P4.L = LO(DMEM_CONTROL);
	P4.H = HI(DMEM_CONTROL);
	R5 = [P4];
	BITCLR(R5,ENDCPLB_P);
	CSYNC;          /* Disabling of CPLBs should be proceeded by a CSYNC */
	[P4] = R5;
	SSYNC;

	/* Fix up the stack */
	(R7:6,P5:4) = [sp++];
	ASTAT = [sp++];
	SP = EX_SCRATCH_REG;

	/* We should be out of the exception stack, and back down into
	 * kernel or user space stack
	 */
	SAVE_ALL_SYS

	/* The dumping functions expect the return address in the RETI
	 * slot.  */
	r6 = retx;
	[sp + PT_PC] = r6;

	r0 = sp;        /* stack frame pt_regs pointer argument ==> r0 */
	SP += -12;
	pseudo_long_call _double_fault_c, p5;
	SP += 12;
.L_double_fault_panic:
        JUMP .L_double_fault_panic

ENDPROC(_double_fault)

ENTRY(_exception_to_level5)
	SAVE_ALL_SYS

	GET_PDA(p5, r7);        /* Fetch current PDA */
	r6 = [p5 + PDA_RETX];
	[sp + PT_PC] = r6;

	r6 = [p5 + PDA_SYSCFG];
	[sp + PT_SYSCFG] = r6;

	r6 = [p5 + PDA_SEQSTAT]; /* Read back seqstat */
	[sp + PT_SEQSTAT] = r6;

	/* Restore the hardware error vector.  */
	r7.h = _evt_ivhw;
	r7.l = _evt_ivhw;
	p4.l = lo(EVT5);
	p4.h = hi(EVT5);
	[p4] = r7;
	csync;

#ifdef CONFIG_DEBUG_DOUBLEFAULT
	/* Now that we have the hardware error vector programmed properly
	 * we can re-enable interrupts (IPEND[4]), so if the _trap_c causes
	 * another hardware error, we can catch it (self-nesting).
	 */
	[--sp] = reti;
	sp += 4;
#endif

	r7 = [p5 + PDA_EXIPEND]	/* Read the IPEND from the Exception state */
	[sp + PT_IPEND] = r7;   /* Store IPEND onto the stack */

	r0 = sp; 	/* stack frame pt_regs pointer argument ==> r0 */
	SP += -12;
	pseudo_long_call _trap_c, p4;
	SP += 12;

	/* If interrupts were off during the exception (IPEND[4] = 1), turn them off
	 * before we return.
	 */
	CC = BITTST(r7, EVT_IRPTEN_P)
	if !CC jump 1f;
	/* this will load a random value into the reti register - but that is OK,
	 * since we do restore it to the correct value in the 'RESTORE_ALL_SYS' macro
	 */
	sp += -4;
	reti = [sp++];
1:
	/* restore the interrupt mask (IMASK) */
	r6 = [p5 + PDA_EXIMASK];
	sti r6;

	call _ret_from_exception;
	RESTORE_ALL_SYS
	rti;
ENDPROC(_exception_to_level5)

ENTRY(_trap) /* Exception: 4th entry into system event table(supervisor mode)*/
	/* Since the kernel stack can be anywhere, it's not guaranteed to be
	 * covered by a CPLB.  Switch to an exception stack; use RETN as a
	 * scratch register (for want of a better option).
	 */
	EX_SCRATCH_REG = sp;
	GET_PDA_SAFE(sp);
	sp = [sp + PDA_EXSTACK];
	/* Try to deal with syscalls quickly.  */
	[--sp] = ASTAT;
	[--sp] = (R7:6,P5:4);

	ANOMALY_283_315_WORKAROUND(p5, r7)

#ifdef CONFIG_EXACT_HWERR
	/* Make sure all pending read/writes complete. This will ensure any
	 * accesses which could cause hardware errors completes, and signal
	 * the the hardware before we do something silly, like crash the
	 * kernel. We don't need to work around anomaly 05000312, since
	 * we are already atomic
	 */
	ssync;
#endif

#ifdef CONFIG_DEBUG_DOUBLEFAULT
	/*
	 * Save these registers, as they are only valid in exception context
	 * (where we are now - as soon as we defer to IRQ5, they can change)
	 * DCPLB_STATUS and ICPLB_STATUS are also only valid in EVT3,
	 * but they are not very interesting, so don't save them
	 */

	GET_PDA(p5, r7);
	p4.l = lo(DCPLB_FAULT_ADDR);
	p4.h = hi(DCPLB_FAULT_ADDR);
	r7 = [p4];
	[p5 + PDA_DF_DCPLB] = r7;

	p4.l = lo(ICPLB_FAULT_ADDR);
	p4.h = hi(ICPLB_FAULT_ADDR);
	r7 = [p4];
	[p5 + PDA_DF_ICPLB] = r7;

	r7 = retx;
	[p5 + PDA_DF_RETX] = r7;

	r7 = SEQSTAT;		/* reason code is in bit 5:0 */
	[p5 + PDA_DF_SEQSTAT] = r7;
#else
	r7 = SEQSTAT;           /* reason code is in bit 5:0 */
#endif
	r6.l = lo(SEQSTAT_EXCAUSE);
	r6.h = hi(SEQSTAT_EXCAUSE);
	r7 = r7 & r6;
	p5.h = _ex_table;
	p5.l = _ex_table;
	p4 = r7;
	p5 = p5 + (p4 << 2);
	p4 = [p5];
	jump (p4);

.Lbadsys:
	r7 = -ENOSYS; 		/* signextending enough */
	[sp + PT_R0] = r7;	/* return value from system call */
	jump .Lsyscall_really_exit;
ENDPROC(_trap)

ENTRY(_kernel_execve)
	link SIZEOF_PTREGS;
	p0 = sp;
	r3 = SIZEOF_PTREGS / 4;
	r4 = 0(x);
.Lclear_regs:
	[p0++] = r4;
	r3 += -1;
	cc = r3 == 0;
	if !cc jump .Lclear_regs (bp);

	p0 = sp;
	sp += -16;
	[sp + 12] = p0;
	pseudo_long_call _do_execve, p5;
	SP += 16;
	cc = r0 == 0;
	if ! cc jump .Lexecve_failed;
	/* Success.  Copy our temporary pt_regs to the top of the kernel
	 * stack and do a normal exception return.
	 */
	r1 = sp;
	r0 = (-KERNEL_STACK_SIZE) (x);
	r1 = r1 & r0;
	p2 = r1;
	p3 = [p2];
	r0 = KERNEL_STACK_SIZE - 4 (z);
	p1 = r0;
	p1 = p1 + p2;

	p0 = fp;
	r4 = [p0--];
	r3 = SIZEOF_PTREGS / 4;
.Lcopy_regs:
	r4 = [p0--];
	[p1--] = r4;
	r3 += -1;
	cc = r3 == 0;
	if ! cc jump .Lcopy_regs (bp);

	r0 = (KERNEL_STACK_SIZE - SIZEOF_PTREGS) (z);
	p1 = r0;
	p1 = p1 + p2;
	sp = p1;
	r0 = syscfg;
	[SP + PT_SYSCFG] = r0;
	[p3 + (TASK_THREAD + THREAD_KSP)] = sp;

	RESTORE_CONTEXT;
	rti;
.Lexecve_failed:
	unlink;
	rts;
ENDPROC(_kernel_execve)

ENTRY(_system_call)
	/* Store IPEND */
	p2.l = lo(IPEND);
	p2.h = hi(IPEND);
	csync;
	r0 = [p2];
	[sp + PT_IPEND] = r0;

	/* Store RETS for now */
	r0 = rets;
	[sp + PT_RESERVED] = r0;
	/* Set the stack for the current process */
	r7 = sp;
	r6.l = lo(ALIGN_PAGE_MASK);
	r6.h = hi(ALIGN_PAGE_MASK);
	r7 = r7 & r6;  		/* thread_info */
	p2 = r7;
	p2 = [p2];

	[p2+(TASK_THREAD+THREAD_KSP)] = sp;
#ifdef CONFIG_IPIPE
	r0 = sp;
	SP += -12;
	pseudo_long_call ___ipipe_syscall_root, p0;
	SP += 12;
	cc = r0 == 1;
	if cc jump .Lsyscall_really_exit;
	cc = r0 == -1;
	if cc jump .Lresume_userspace;
	r3 = [sp + PT_R3];
	r4 = [sp + PT_R4];
	p0 = [sp + PT_ORIG_P0];
#endif /* CONFIG_IPIPE */

	/* are we tracing syscalls?*/
	r7 = sp;
	r6.l = lo(ALIGN_PAGE_MASK);
	r6.h = hi(ALIGN_PAGE_MASK);
	r7 = r7 & r6;
	p2 = r7;
	r7 = [p2+TI_FLAGS];
	CC = BITTST(r7,TIF_SYSCALL_TRACE);
	if CC JUMP _sys_trace;
	CC = BITTST(r7,TIF_SINGLESTEP);
	if CC JUMP _sys_trace;

	/* Make sure the system call # is valid */
	p4 = __NR_syscall;
	/* System call number is passed in P0 */
	cc = p4 <= p0;
	if cc jump .Lbadsys;

	/* Execute the appropriate system call */

	p4 = p0;
	p5.l = _sys_call_table;
	p5.h = _sys_call_table;
	p5 = p5 + (p4 << 2);
	r0 = [sp + PT_R0];
	r1 = [sp + PT_R1];
	r2 = [sp + PT_R2];
	p5 = [p5];

	[--sp] = r5;
	[--sp] = r4;
	[--sp] = r3;
	SP += -12;
	call (p5);
	SP += 24;
	[sp + PT_R0] = r0;

.Lresume_userspace:
	r7 = sp;
	r4.l = lo(ALIGN_PAGE_MASK);
	r4.h = hi(ALIGN_PAGE_MASK);
	r7 = r7 & r4;		/* thread_info->flags */
	p5 = r7;
.Lresume_userspace_1:
	/* Disable interrupts.  */
	[--sp] = reti;
	reti = [sp++];

	r7 = [p5 + TI_FLAGS];
	r4.l = lo(_TIF_WORK_MASK);
	r4.h = hi(_TIF_WORK_MASK);
	r7 =  r7 & r4;

.Lsyscall_resched:
#ifdef CONFIG_IPIPE
	cc = BITTST(r7, TIF_IRQ_SYNC);
	if !cc jump .Lsyscall_no_irqsync;
	/*
	 * Clear IPEND[4] manually to undo what resume_userspace_1 just did;
	 * we need this so that high priority domain interrupts may still
	 * preempt the current domain while the pipeline log is being played
	 * back.
	 */
	[--sp] = reti;
	SP += 4; /* don't merge with next insn to keep the pattern obvious */
	SP += -12;
	pseudo_long_call ___ipipe_sync_root, p4;
	SP += 12;
	jump .Lresume_userspace_1;
.Lsyscall_no_irqsync:
#endif
	cc = BITTST(r7, TIF_NEED_RESCHED);
	if !cc jump .Lsyscall_sigpending;

	/* Reenable interrupts.  */
	[--sp] = reti;
	sp += 4;

	SP += -12;
	pseudo_long_call _schedule, p4;
	SP += 12;

	jump .Lresume_userspace_1;

.Lsyscall_sigpending:
	cc = BITTST(r7, TIF_SIGPENDING);
	if cc jump .Lsyscall_do_signals;
	cc = BITTST(r7, TIF_NOTIFY_RESUME);
	if !cc jump .Lsyscall_really_exit;
.Lsyscall_do_signals:
	/* Reenable interrupts.  */
	[--sp] = reti;
	sp += 4;

	r0 = sp;
	SP += -12;
	pseudo_long_call _do_notify_resume, p5;
	SP += 12;

.Lsyscall_really_exit:
	r5 = [sp + PT_RESERVED];
	rets = r5;
	rts;
ENDPROC(_system_call)

/* Do not mark as ENTRY() to avoid error in assembler ...
 * this symbol need not be global anyways, so ...
 */
_sys_trace:
	r0 = sp;
	pseudo_long_call _syscall_trace_enter, p5;

	/* Make sure the system call # is valid */
	p4 = [SP + PT_P0];
	p3 = __NR_syscall;
	cc = p3 <= p4;
	r0 = -ENOSYS;
	if cc jump .Lsys_trace_badsys;

	/* Execute the appropriate system call */
	p5.l = _sys_call_table;
	p5.h = _sys_call_table;
	p5 = p5 + (p4 << 2);
	r0 = [sp + PT_R0];
	r1 = [sp + PT_R1];
	r2 = [sp + PT_R2];
	r3 = [sp + PT_R3];
	r4 = [sp + PT_R4];
	r5 = [sp + PT_R5];
	p5 = [p5];

	[--sp] = r5;
	[--sp] = r4;
	[--sp] = r3;
	SP += -12;
	call (p5);
	SP += 24;
.Lsys_trace_badsys:
	[sp + PT_R0] = r0;

	r0 = sp;
	pseudo_long_call _syscall_trace_leave, p5;
	jump .Lresume_userspace;
ENDPROC(_sys_trace)

ENTRY(_resume)
	/*
	 * Beware - when entering resume, prev (the current task) is
	 * in r0, next (the new task) is in r1.
	 */
	p0 = r0;
	p1 = r1;
	[--sp] = rets;
	[--sp] = fp;
	[--sp] = (r7:4, p5:3);

	/* save usp */
	p2 = usp;
	[p0+(TASK_THREAD+THREAD_USP)] = p2;

	/* save current kernel stack pointer */
	[p0+(TASK_THREAD+THREAD_KSP)] = sp;

	/* save program counter */
	r1.l = _new_old_task;
	r1.h = _new_old_task;
	[p0+(TASK_THREAD+THREAD_PC)] = r1;

	/* restore the kernel stack pointer */
	sp = [p1+(TASK_THREAD+THREAD_KSP)];

	/* restore user stack pointer */
	p0 = [p1+(TASK_THREAD+THREAD_USP)];
	usp = p0;

	/* restore pc */
	p0 = [p1+(TASK_THREAD+THREAD_PC)];
	jump (p0);

	/*
	 * Following code actually lands up in a new (old) task.
	 */

_new_old_task:
	(r7:4, p5:3) = [sp++];
	fp = [sp++];
	rets = [sp++];

	/*
	 * When we come out of resume, r0 carries "old" task, because we are
	 * in "new" task.
	 */
	rts;
ENDPROC(_resume)

ENTRY(_ret_from_exception)
#ifdef CONFIG_IPIPE
	p2.l = _ipipe_percpu_domain;
	p2.h = _ipipe_percpu_domain;
	r0.l = _ipipe_root;
	r0.h = _ipipe_root;
	r2 = [p2];
	cc = r0 == r2;
	if !cc jump 4f;  /* not on behalf of the root domain, get out */
#endif /* CONFIG_IPIPE */
	p2.l = lo(IPEND);
	p2.h = hi(IPEND);

	csync;
	r0 = [p2];
	[sp + PT_IPEND] = r0;

1:
	r2 = LO(~0x37) (Z);
	r0 = r2 & r0;
	cc = r0 == 0;
	if !cc jump 4f;	/* if not return to user mode, get out */

	/* Make sure any pending system call or deferred exception
	 * return in ILAT for this process to get executed, otherwise
	 * in case context switch happens, system call of
	 * first process (i.e in ILAT) will be carried
	 * forward to the switched process
	 */

	p2.l = lo(ILAT);
	p2.h = hi(ILAT);
	r0 = [p2];
	r1 = (EVT_IVG14 | EVT_IVG15) (z);
	r0 = r0 & r1;
	cc = r0 == 0;
	if !cc jump 5f;

	/* Set the stack for the current process */
	r7 = sp;
	r4.l = lo(ALIGN_PAGE_MASK);
	r4.h = hi(ALIGN_PAGE_MASK);
	r7 = r7 & r4;		/* thread_info->flags */
	p5 = r7;
	r7 = [p5 + TI_FLAGS];
	r4.l = lo(_TIF_WORK_MASK);
	r4.h = hi(_TIF_WORK_MASK);
	r7 =  r7 & r4;
	cc = r7 == 0;
	if cc jump 4f;

	p0.l = lo(EVT15);
	p0.h = hi(EVT15);
	p1.l = _schedule_and_signal;
	p1.h = _schedule_and_signal;
	[p0] = p1;
	csync;
	raise 15;		/* raise evt15 to do signal or reschedule */
4:
	r0 = syscfg;
	bitclr(r0, SYSCFG_SSSTEP_P);		/* Turn off single step */
	syscfg = r0;
5:
	rts;
ENDPROC(_ret_from_exception)

#if defined(CONFIG_PREEMPT)

ENTRY(_up_to_irq14)
#if ANOMALY_05000281 || ANOMALY_05000461
	r0.l = lo(SAFE_USER_INSTRUCTION);
	r0.h = hi(SAFE_USER_INSTRUCTION);
	reti = r0;
#endif

#ifdef CONFIG_DEBUG_HWERR
	/* enable irq14 & hwerr interrupt, until we transition to _evt_evt14 */
	r0 = (EVT_IVG14 | EVT_IVHW | EVT_IRPTEN | EVT_EVX | EVT_NMI | EVT_RST | EVT_EMU);
#else
	/* Only enable irq14 interrupt, until we transition to _evt_evt14 */
	r0 = (EVT_IVG14 | EVT_IRPTEN | EVT_EVX | EVT_NMI | EVT_RST | EVT_EMU);
#endif
	sti r0;

	p0.l = lo(EVT14);
	p0.h = hi(EVT14);
	p1.l = _evt_up_evt14;
	p1.h = _evt_up_evt14;
	[p0] = p1;
	csync;

	raise 14;
1:
	jump 1b;
ENDPROC(_up_to_irq14)

ENTRY(_evt_up_evt14)
#ifdef CONFIG_DEBUG_HWERR
	r0 = (EVT_IVHW | EVT_IRPTEN | EVT_EVX | EVT_NMI | EVT_RST | EVT_EMU);
	sti r0;
#else
	cli r0;
#endif
#ifdef CONFIG_TRACE_IRQFLAGS
	[--sp] = rets;
	sp += -12;
	call _trace_hardirqs_off;
	sp += 12;
	rets = [sp++];
#endif
	[--sp] = RETI;
	SP += 4;

	/* restore normal evt14 */
	p0.l = lo(EVT14);
	p0.h = hi(EVT14);
	p1.l = _evt_evt14;
	p1.h = _evt_evt14;
	[p0] = p1;
	csync;

	rts;
ENDPROC(_evt_up_evt14)

#endif

#ifdef CONFIG_IPIPE

_resume_kernel_from_int:
	r1 = LO(~0x8000) (Z);
	r1 = r0 & r1;
	r0 = 1;
	r0 = r1 - r0;
	r2 = r1 & r0;
	cc = r2 == 0;
	/* Sync the root stage only from the outer interrupt level. */
	if !cc jump .Lnosync;
	r0.l = ___ipipe_sync_root;
	r0.h = ___ipipe_sync_root;
	[--sp] = reti;
	[--sp] = rets;
	[--sp] = ( r7:4, p5:3 );
	SP += -12;
	call ___ipipe_call_irqtail
	SP += 12;
	( r7:4, p5:3 ) = [sp++];
	rets = [sp++];
	reti = [sp++];
.Lnosync:
	rts
#elif defined(CONFIG_PREEMPT)

_resume_kernel_from_int:
	/* check preempt_count */
	r7 = sp;
	r4.l = lo(ALIGN_PAGE_MASK);
	r4.h = hi(ALIGN_PAGE_MASK);
	r7 = r7 & r4;
	p5 = r7;
	r7 = [p5 + TI_PREEMPT];
	cc = r7 == 0x0;
	if !cc jump .Lreturn_to_kernel;
.Lneed_schedule:
	r7 = [p5 + TI_FLAGS];
	r4.l = lo(_TIF_WORK_MASK);
	r4.h = hi(_TIF_WORK_MASK);
	r7 =  r7 & r4;
	cc = BITTST(r7, TIF_NEED_RESCHED);
	if !cc jump .Lreturn_to_kernel;
	/*
	 * let schedule done at level 15, otherwise sheduled process will run
	 * at high level and block low level interrupt
	 */
	r6 = reti;  /* save reti */
	r5.l = .Lkernel_schedule;
	r5.h = .Lkernel_schedule;
	reti = r5;
	rti;
.Lkernel_schedule:
	[--sp] = rets;
	sp += -12;
	pseudo_long_call _preempt_schedule_irq, p4;
	sp += 12;
	rets = [sp++];

	[--sp] = rets;
	sp += -12;
	/* up to irq14 so that reti after restore_all can return to irq15(kernel) */
	pseudo_long_call _up_to_irq14, p4;
	sp += 12;
	rets = [sp++];

	reti = r6; /* restore reti so that origin process can return to interrupted point */

	jump .Lneed_schedule;
#else

#define _resume_kernel_from_int	.Lreturn_to_kernel
#endif

ENTRY(_return_from_int)
	/* If someone else already raised IRQ 15, do nothing.  */
	csync;
	p2.l = lo(ILAT);
	p2.h = hi(ILAT);
	r0 = [p2];
	cc = bittst (r0, EVT_IVG15_P);
	if cc jump .Lreturn_to_kernel;

	/* if not return to user mode, get out */
	p2.l = lo(IPEND);
	p2.h = hi(IPEND);
	r0 = [p2];
	r1 = 0x17(Z);
	r2 = ~r1;
	r2.h = 0;
	r0 = r2 & r0;
	r1 = 1;
	r1 = r0 - r1;
	r2 = r0 & r1;
	cc = r2 == 0;
	if !cc jump _resume_kernel_from_int;

	/* Lower the interrupt level to 15.  */
	p0.l = lo(EVT15);
	p0.h = hi(EVT15);
	p1.l = _schedule_and_signal_from_int;
	p1.h = _schedule_and_signal_from_int;
	[p0] = p1;
	csync;
#if ANOMALY_05000281 || ANOMALY_05000461
	r0.l = lo(SAFE_USER_INSTRUCTION);
	r0.h = hi(SAFE_USER_INSTRUCTION);
	reti = r0;
#endif
	r0 = 0x801f (z);
	STI r0;
	raise 15;	/* raise evt15 to do signal or reschedule */
	rti;
.Lreturn_to_kernel:
	rts;
ENDPROC(_return_from_int)

ENTRY(_lower_to_irq14)
#if ANOMALY_05000281 || ANOMALY_05000461
	r0.l = lo(SAFE_USER_INSTRUCTION);
	r0.h = hi(SAFE_USER_INSTRUCTION);
	reti = r0;
#endif

#ifdef CONFIG_DEBUG_HWERR
	/* enable irq14 & hwerr interrupt, until we transition to _evt_evt14 */
	r0 = (EVT_IVG14 | EVT_IVHW | EVT_IRPTEN | EVT_EVX | EVT_NMI | EVT_RST | EVT_EMU);
#else
	/* Only enable irq14 interrupt, until we transition to _evt_evt14 */
	r0 = (EVT_IVG14 | EVT_IRPTEN | EVT_EVX | EVT_NMI | EVT_RST | EVT_EMU);
#endif
	sti r0;
	raise 14;
	rti;
ENDPROC(_lower_to_irq14)

ENTRY(_evt_evt14)
#ifdef CONFIG_DEBUG_HWERR
	r0 = (EVT_IVHW | EVT_IRPTEN | EVT_EVX | EVT_NMI | EVT_RST | EVT_EMU);
	sti r0;
#else
	cli r0;
#endif
#ifdef CONFIG_TRACE_IRQFLAGS
	[--sp] = rets;
	sp += -12;
	call _trace_hardirqs_off;
	sp += 12;
	rets = [sp++];
#endif
	[--sp] = RETI;
	SP += 4;
	rts;
ENDPROC(_evt_evt14)

ENTRY(_schedule_and_signal_from_int)
	/* To end up here, vector 15 was changed - so we have to change it
	 * back.
	 */
	p0.l = lo(EVT15);
	p0.h = hi(EVT15);
	p1.l = _evt_system_call;
	p1.h = _evt_system_call;
	[p0] = p1;
	csync;

	/* Set orig_p0 to -1 to indicate this isn't the end of a syscall.  */
	r0 = -1 (x);
	[sp + PT_ORIG_P0] = r0;

	p1 = rets;
	[sp + PT_RESERVED] = p1;

#ifdef CONFIG_TRACE_IRQFLAGS
	/* trace_hardirqs_on() checks if all irqs are disabled. But here IRQ 15
	 * is turned on, so disable all irqs. */
	cli r0;
	sp += -12;
	call _trace_hardirqs_on;
	sp += 12;
#endif
#ifdef CONFIG_SMP
	GET_PDA(p0, r0); 	/* Fetch current PDA (can't migrate to other CPU here) */
	r0 = [p0 + PDA_IRQFLAGS];
#else
	p0.l = _bfin_irq_flags;
	p0.h = _bfin_irq_flags;
	r0 = [p0];
#endif
	sti r0;

	/* finish the userspace "atomic" functions for it */
	r1.l = lo(FIXED_CODE_END);
	r1.h = hi(FIXED_CODE_END);
	r2 = [sp + PT_PC];
	cc = r1 <= r2;
	if cc jump .Lresume_userspace (bp);

	r0 = sp;
	sp += -12;

	pseudo_long_call _finish_atomic_sections, p5;
	sp += 12;
	jump.s .Lresume_userspace;
ENDPROC(_schedule_and_signal_from_int)

ENTRY(_schedule_and_signal)
	SAVE_CONTEXT_SYSCALL
	/* To end up here, vector 15 was changed - so we have to change it
	 * back.
	 */
	p0.l = lo(EVT15);
	p0.h = hi(EVT15);
	p1.l = _evt_system_call;
	p1.h = _evt_system_call;
	[p0] = p1;
	csync;
	p0.l = 1f;
	p0.h = 1f;
	[sp + PT_RESERVED] = P0;
	call .Lresume_userspace;
1:
	RESTORE_CONTEXT
	rti;
ENDPROC(_schedule_and_signal)

/* We handle this 100% in exception space - to reduce overhead
 * Only potiential problem is if the software buffer gets swapped out of the
 * CPLB table - then double fault. - so we don't let this happen in other places
 */
#ifdef CONFIG_DEBUG_BFIN_HWTRACE_EXPAND
ENTRY(_ex_trace_buff_full)
	[--sp] = P3;
	[--sp] = P2;
	[--sp] = LC0;
	[--sp] = LT0;
	[--sp] = LB0;
	P5.L = _trace_buff_offset;
	P5.H = _trace_buff_offset;
	P3 = [P5];              /* trace_buff_offset */
	P5.L = lo(TBUFSTAT);
	P5.H = hi(TBUFSTAT);
	R7 = [P5];
	R7 <<= 1;               /* double, since we need to read twice */
	LC0 = R7;
	R7 <<= 2;               /* need to shift over again,
				 * to get the number of bytes */
	P5.L = lo(TBUF);
	P5.H = hi(TBUF);
	R6 = ((1 << CONFIG_DEBUG_BFIN_HWTRACE_EXPAND_LEN)*1024) - 1;

	P2 = R7;
	P3 = P3 + P2;
	R7 = P3;
	R7 = R7 & R6;
	P3 = R7;
	P2.L = _trace_buff_offset;
	P2.H = _trace_buff_offset;
	[P2] = P3;

	P2.L = _software_trace_buff;
	P2.H = _software_trace_buff;

	LSETUP (.Lstart, .Lend) LC0;
.Lstart:
	R7 = [P5];      /* read TBUF */
	P4 = P3 + P2;
	[P4] = R7;
	P3 += -4;
	R7 = P3;
	R7 = R7 & R6;
.Lend:
	P3 = R7;

	LB0 = [sp++];
	LT0 = [sp++];
	LC0 = [sp++];
	P2 = [sp++];
	P3 = [sp++];
	jump _bfin_return_from_exception;
ENDPROC(_ex_trace_buff_full)

#if CONFIG_DEBUG_BFIN_HWTRACE_EXPAND_LEN == 4
.data
#else
.section .l1.data.B
#endif /* CONFIG_DEBUG_BFIN_HWTRACE_EXPAND_LEN */
ENTRY(_trace_buff_offset)
        .long 0;
ALIGN
ENTRY(_software_trace_buff)
	.rept ((1 << CONFIG_DEBUG_BFIN_HWTRACE_EXPAND_LEN)*256);
	.long 0
	.endr
#endif /* CONFIG_DEBUG_BFIN_HWTRACE_EXPAND */

#ifdef CONFIG_EARLY_PRINTK
__INIT
ENTRY(_early_trap)
	SAVE_ALL_SYS
	trace_buffer_stop(p0,r0);

	ANOMALY_283_315_WORKAROUND(p4, r5)

	/* Turn caches off, to ensure we don't get double exceptions */

	P4.L = LO(IMEM_CONTROL);
	P4.H = HI(IMEM_CONTROL);

	R5 = [P4];              /* Control Register*/
	BITCLR(R5,ENICPLB_P);
	CSYNC;          /* Disabling of CPLBs should be proceeded by a CSYNC */
	[P4] = R5;
	SSYNC;

	P4.L = LO(DMEM_CONTROL);
	P4.H = HI(DMEM_CONTROL);
	R5 = [P4];
	BITCLR(R5,ENDCPLB_P);
	CSYNC;          /* Disabling of CPLBs should be proceeded by a CSYNC */
	[P4] = R5;
	SSYNC;

	r0 = sp;        /* stack frame pt_regs pointer argument ==> r0 */
	r1 = RETX;

	SP += -12;
	call _early_trap_c;
	SP += 12;
ENDPROC(_early_trap)
__FINIT
#endif /* CONFIG_EARLY_PRINTK */

/*
 * Put these in the kernel data section - that should always be covered by
 * a CPLB. This is needed to ensure we don't get double fault conditions
 */

#ifdef CONFIG_SYSCALL_TAB_L1
.section .l1.data
#else
.data
#endif

ENTRY(_ex_table)
	/* entry for each EXCAUSE[5:0]
	 * This table must be in sync with the table in ./kernel/traps.c
	 * EXCPT instruction can provide 4 bits of EXCAUSE, allowing 16 to be user defined
	 */
	.long _ex_syscall       /* 0x00 - User Defined - Linux Syscall */
	.long _ex_trap_c        /* 0x01 - User Defined - Software breakpoint */
#ifdef	CONFIG_KGDB
	.long _ex_trap_c	/* 0x02 - User Defined - KGDB initial connection
							 and break signal trap */
#else
	.long _ex_replaceable   /* 0x02 - User Defined */
#endif
	.long _ex_trap_c        /* 0x03 - User Defined - userspace stack overflow */
	.long _ex_trap_c        /* 0x04 - User Defined - dump trace buffer */
	.long _ex_replaceable   /* 0x05 - User Defined */
	.long _ex_replaceable   /* 0x06 - User Defined */
	.long _ex_replaceable   /* 0x07 - User Defined */
	.long _ex_replaceable   /* 0x08 - User Defined */
	.long _ex_replaceable   /* 0x09 - User Defined */
	.long _ex_replaceable   /* 0x0A - User Defined */
	.long _ex_replaceable   /* 0x0B - User Defined */
	.long _ex_replaceable   /* 0x0C - User Defined */
	.long _ex_replaceable   /* 0x0D - User Defined */
	.long _ex_replaceable   /* 0x0E - User Defined */
	.long _ex_replaceable   /* 0x0F - User Defined */
	.long _ex_single_step   /* 0x10 - HW Single step */
#ifdef CONFIG_DEBUG_BFIN_HWTRACE_EXPAND
	.long _ex_trace_buff_full /* 0x11 - Trace Buffer Full */
#else
	.long _ex_trap_c        /* 0x11 - Trace Buffer Full */
#endif
	.long _ex_trap_c        /* 0x12 - Reserved */
	.long _ex_trap_c        /* 0x13 - Reserved */
	.long _ex_trap_c        /* 0x14 - Reserved */
	.long _ex_trap_c        /* 0x15 - Reserved */
	.long _ex_trap_c        /* 0x16 - Reserved */
	.long _ex_trap_c        /* 0x17 - Reserved */
	.long _ex_trap_c        /* 0x18 - Reserved */
	.long _ex_trap_c        /* 0x19 - Reserved */
	.long _ex_trap_c        /* 0x1A - Reserved */
	.long _ex_trap_c        /* 0x1B - Reserved */
	.long _ex_trap_c        /* 0x1C - Reserved */
	.long _ex_trap_c        /* 0x1D - Reserved */
	.long _ex_trap_c        /* 0x1E - Reserved */
	.long _ex_trap_c        /* 0x1F - Reserved */
	.long _ex_trap_c        /* 0x20 - Reserved */
	.long _ex_trap_c        /* 0x21 - Undefined Instruction */
	.long _ex_trap_c        /* 0x22 - Illegal Instruction Combination */
	.long _ex_dviol         /* 0x23 - Data CPLB Protection Violation */
	.long _ex_trap_c        /* 0x24 - Data access misaligned */
	.long _ex_trap_c        /* 0x25 - Unrecoverable Event */
	.long _ex_dmiss         /* 0x26 - Data CPLB Miss */
	.long _ex_dmult         /* 0x27 - Data CPLB Multiple Hits - Linux Trap Zero */
	.long _ex_trap_c        /* 0x28 - Emulation Watchpoint */
	.long _ex_trap_c        /* 0x29 - Instruction fetch access error (535 only) */
	.long _ex_trap_c        /* 0x2A - Instruction fetch misaligned */
	.long _ex_trap_c        /* 0x2B - Instruction CPLB protection Violation */
	.long _ex_icplb_miss    /* 0x2C - Instruction CPLB miss */
	.long _ex_trap_c        /* 0x2D - Instruction CPLB Multiple Hits */
	.long _ex_trap_c        /* 0x2E - Illegal use of Supervisor Resource */
	.long _ex_trap_c        /* 0x2E - Illegal use of Supervisor Resource */
	.long _ex_trap_c        /* 0x2F - Reserved */
	.long _ex_trap_c        /* 0x30 - Reserved */
	.long _ex_trap_c        /* 0x31 - Reserved */
	.long _ex_trap_c        /* 0x32 - Reserved */
	.long _ex_trap_c        /* 0x33 - Reserved */
	.long _ex_trap_c        /* 0x34 - Reserved */
	.long _ex_trap_c        /* 0x35 - Reserved */
	.long _ex_trap_c        /* 0x36 - Reserved */
	.long _ex_trap_c        /* 0x37 - Reserved */
	.long _ex_trap_c        /* 0x38 - Reserved */
	.long _ex_trap_c        /* 0x39 - Reserved */
	.long _ex_trap_c        /* 0x3A - Reserved */
	.long _ex_trap_c        /* 0x3B - Reserved */
	.long _ex_trap_c        /* 0x3C - Reserved */
	.long _ex_trap_c        /* 0x3D - Reserved */
	.long _ex_trap_c        /* 0x3E - Reserved */
	.long _ex_trap_c        /* 0x3F - Reserved */
END(_ex_table)

ENTRY(_sys_call_table)
	.long _sys_restart_syscall	/* 0 */
	.long _sys_exit
	.long _sys_ni_syscall	/* fork */
	.long _sys_read
	.long _sys_write
	.long _sys_open		/* 5 */
	.long _sys_close
	.long _sys_ni_syscall	/* old waitpid */
	.long _sys_creat
	.long _sys_link
	.long _sys_unlink	/* 10 */
	.long _sys_execve
	.long _sys_chdir
	.long _sys_time
	.long _sys_mknod
	.long _sys_chmod		/* 15 */
	.long _sys_chown	/* chown16 */
	.long _sys_ni_syscall	/* old break syscall holder */
	.long _sys_ni_syscall	/* old stat */
	.long _sys_lseek
	.long _sys_getpid	/* 20 */
	.long _sys_mount
	.long _sys_ni_syscall	/* old umount */
	.long _sys_setuid
	.long _sys_getuid
	.long _sys_stime		/* 25 */
	.long _sys_ptrace
	.long _sys_alarm
	.long _sys_ni_syscall	/* old fstat */
	.long _sys_pause
	.long _sys_ni_syscall	/* old utime */ /* 30 */
	.long _sys_ni_syscall	/* old stty syscall holder */
	.long _sys_ni_syscall	/* old gtty syscall holder */
	.long _sys_access
	.long _sys_nice
	.long _sys_ni_syscall	/* 35 */ /* old ftime syscall holder */
	.long _sys_sync
	.long _sys_kill
	.long _sys_rename
	.long _sys_mkdir
	.long _sys_rmdir		/* 40 */
	.long _sys_dup
	.long _sys_pipe
	.long _sys_times
	.long _sys_ni_syscall	/* old prof syscall holder */
	.long _sys_brk		/* 45 */
	.long _sys_setgid
	.long _sys_getgid
	.long _sys_ni_syscall	/* old sys_signal */
	.long _sys_geteuid	/* geteuid16 */
	.long _sys_getegid	/* getegid16 */	/* 50 */
	.long _sys_acct
	.long _sys_umount	/* recycled never used phys() */
	.long _sys_ni_syscall	/* old lock syscall holder */
	.long _sys_ioctl
	.long _sys_fcntl		/* 55 */
	.long _sys_ni_syscall	/* old mpx syscall holder */
	.long _sys_setpgid
	.long _sys_ni_syscall	/* old ulimit syscall holder */
	.long _sys_ni_syscall	/* old old uname */
	.long _sys_umask		/* 60 */
	.long _sys_chroot
	.long _sys_ustat
	.long _sys_dup2
	.long _sys_getppid
	.long _sys_getpgrp	/* 65 */
	.long _sys_setsid
	.long _sys_ni_syscall	/* old sys_sigaction */
	.long _sys_sgetmask
	.long _sys_ssetmask
	.long _sys_setreuid	/* setreuid16 */	/* 70 */
	.long _sys_setregid	/* setregid16 */
	.long _sys_ni_syscall	/* old sys_sigsuspend */
	.long _sys_ni_syscall	/* old sys_sigpending */
	.long _sys_sethostname
	.long _sys_setrlimit	/* 75 */
	.long _sys_ni_syscall	/* old getrlimit */
	.long _sys_getrusage
	.long _sys_gettimeofday
	.long _sys_settimeofday
	.long _sys_getgroups	/* getgroups16 */	/* 80 */
	.long _sys_setgroups	/* setgroups16 */
	.long _sys_ni_syscall	/* old_select */
	.long _sys_symlink
	.long _sys_ni_syscall	/* old lstat */
	.long _sys_readlink	/* 85 */
	.long _sys_uselib
	.long _sys_ni_syscall	/* sys_swapon */
	.long _sys_reboot
	.long _sys_ni_syscall	/* old_readdir */
	.long _sys_ni_syscall	/* sys_mmap */	/* 90 */
	.long _sys_munmap
	.long _sys_truncate
	.long _sys_ftruncate
	.long _sys_fchmod
	.long _sys_fchown	/* fchown16 */	/* 95 */
	.long _sys_getpriority
	.long _sys_setpriority
	.long _sys_ni_syscall	/* old profil syscall holder */
	.long _sys_statfs
	.long _sys_fstatfs	/* 100 */
	.long _sys_ni_syscall
	.long _sys_ni_syscall	/* old sys_socketcall */
	.long _sys_syslog
	.long _sys_setitimer
	.long _sys_getitimer	/* 105 */
	.long _sys_newstat
	.long _sys_newlstat
	.long _sys_newfstat
	.long _sys_ni_syscall	/* old uname */
	.long _sys_ni_syscall	/* iopl for i386 */ /* 110 */
	.long _sys_vhangup
	.long _sys_ni_syscall	/* obsolete idle() syscall */
	.long _sys_ni_syscall	/* vm86old for i386 */
	.long _sys_wait4
	.long _sys_ni_syscall	/* 115 */ /* sys_swapoff */
	.long _sys_sysinfo
	.long _sys_ni_syscall	/* old sys_ipc */
	.long _sys_fsync
	.long _sys_ni_syscall	/* old sys_sigreturn */
	.long _sys_clone		/* 120 */
	.long _sys_setdomainname
	.long _sys_newuname
	.long _sys_ni_syscall	/* old sys_modify_ldt */
	.long _sys_adjtimex
	.long _sys_mprotect	/* 125 */
	.long _sys_ni_syscall	/* old sys_sigprocmask */
	.long _sys_ni_syscall	/* old "creat_module" */
	.long _sys_init_module
	.long _sys_delete_module
	.long _sys_ni_syscall	/* 130: old "get_kernel_syms" */
	.long _sys_quotactl
	.long _sys_getpgid
	.long _sys_fchdir
	.long _sys_bdflush
	.long _sys_ni_syscall	/* 135 */ /* sys_sysfs */
	.long _sys_personality
	.long _sys_ni_syscall	/* for afs_syscall */
	.long _sys_setfsuid	/* setfsuid16 */
	.long _sys_setfsgid	/* setfsgid16 */
	.long _sys_llseek	/* 140 */
	.long _sys_getdents
	.long _sys_ni_syscall	/* sys_select */
	.long _sys_flock
	.long _sys_msync
	.long _sys_readv		/* 145 */
	.long _sys_writev
	.long _sys_getsid
	.long _sys_fdatasync
	.long _sys_sysctl
	.long _sys_mlock	/* 150 */
	.long _sys_munlock
	.long _sys_mlockall
	.long _sys_munlockall
	.long _sys_sched_setparam
	.long _sys_sched_getparam /* 155 */
	.long _sys_sched_setscheduler
	.long _sys_sched_getscheduler
	.long _sys_sched_yield
	.long _sys_sched_get_priority_max
	.long _sys_sched_get_priority_min  /* 160 */
	.long _sys_sched_rr_get_interval
	.long _sys_nanosleep
	.long _sys_mremap
	.long _sys_setresuid	/* setresuid16 */
	.long _sys_getresuid	/* getresuid16 */	/* 165 */
	.long _sys_ni_syscall	/* for vm86 */
	.long _sys_ni_syscall	/* old "query_module" */
	.long _sys_ni_syscall	/* sys_poll */
	.long _sys_ni_syscall   /* old nfsservctl */
	.long _sys_setresgid	/* setresgid16 */	/* 170 */
	.long _sys_getresgid	/* getresgid16 */
	.long _sys_prctl
	.long _sys_rt_sigreturn
	.long _sys_rt_sigaction
	.long _sys_rt_sigprocmask /* 175 */
	.long _sys_rt_sigpending
	.long _sys_rt_sigtimedwait
	.long _sys_rt_sigqueueinfo
	.long _sys_rt_sigsuspend
	.long _sys_pread64	/* 180 */
	.long _sys_pwrite64
	.long _sys_lchown	/* lchown16 */
	.long _sys_getcwd
	.long _sys_capget
	.long _sys_capset	/* 185 */
	.long _sys_sigaltstack
	.long _sys_sendfile
	.long _sys_ni_syscall	/* streams1 */
	.long _sys_ni_syscall	/* streams2 */
	.long _sys_vfork		/* 190 */
	.long _sys_getrlimit
	.long _sys_mmap_pgoff
	.long _sys_truncate64
	.long _sys_ftruncate64
	.long _sys_stat64	/* 195 */
	.long _sys_lstat64
	.long _sys_fstat64
	.long _sys_chown
	.long _sys_getuid
	.long _sys_getgid	/* 200 */
	.long _sys_geteuid
	.long _sys_getegid
	.long _sys_setreuid
	.long _sys_setregid
	.long _sys_getgroups	/* 205 */
	.long _sys_setgroups
	.long _sys_fchown
	.long _sys_setresuid
	.long _sys_getresuid
	.long _sys_setresgid	/* 210 */
	.long _sys_getresgid
	.long _sys_lchown
	.long _sys_setuid
	.long _sys_setgid
	.long _sys_setfsuid	/* 215 */
	.long _sys_setfsgid
	.long _sys_pivot_root
	.long _sys_mincore
	.long _sys_madvise
	.long _sys_getdents64	/* 220 */
	.long _sys_fcntl64
	.long _sys_ni_syscall	/* reserved for TUX */
	.long _sys_ni_syscall
	.long _sys_gettid
	.long _sys_readahead	/* 225 */
	.long _sys_setxattr
	.long _sys_lsetxattr
	.long _sys_fsetxattr
	.long _sys_getxattr
	.long _sys_lgetxattr	/* 230 */
	.long _sys_fgetxattr
	.long _sys_listxattr
	.long _sys_llistxattr
	.long _sys_flistxattr
	.long _sys_removexattr	/* 235 */
	.long _sys_lremovexattr
	.long _sys_fremovexattr
	.long _sys_tkill
	.long _sys_sendfile64
	.long _sys_futex		/* 240 */
	.long _sys_sched_setaffinity
	.long _sys_sched_getaffinity
	.long _sys_ni_syscall	/* sys_set_thread_area */
	.long _sys_ni_syscall	/* sys_get_thread_area */
	.long _sys_io_setup	/* 245 */
	.long _sys_io_destroy
	.long _sys_io_getevents
	.long _sys_io_submit
	.long _sys_io_cancel
	.long _sys_ni_syscall	/* 250 */ /* sys_alloc_hugepages */
	.long _sys_ni_syscall	/* sys_freec_hugepages */
	.long _sys_exit_group
	.long _sys_lookup_dcookie
	.long _sys_bfin_spinlock
	.long _sys_epoll_create	/* 255 */
	.long _sys_epoll_ctl
	.long _sys_epoll_wait
	.long _sys_ni_syscall /* remap_file_pages */
	.long _sys_set_tid_address
	.long _sys_timer_create	/* 260 */
	.long _sys_timer_settime
	.long _sys_timer_gettime
	.long _sys_timer_getoverrun
	.long _sys_timer_delete
	.long _sys_clock_settime /* 265 */
	.long _sys_clock_gettime
	.long _sys_clock_getres
	.long _sys_clock_nanosleep
	.long _sys_statfs64
	.long _sys_fstatfs64	/* 270 */
	.long _sys_tgkill
	.long _sys_utimes
	.long _sys_fadvise64_64
	.long _sys_ni_syscall /* vserver */
	.long _sys_mbind	/* 275 */
	.long _sys_ni_syscall /* get_mempolicy */
	.long _sys_ni_syscall /* set_mempolicy */
	.long _sys_mq_open
	.long _sys_mq_unlink
	.long _sys_mq_timedsend	/* 280 */
	.long _sys_mq_timedreceive
	.long _sys_mq_notify
	.long _sys_mq_getsetattr
	.long _sys_ni_syscall /* kexec_load */
	.long _sys_waitid	/* 285 */
	.long _sys_add_key
	.long _sys_request_key
	.long _sys_keyctl
	.long _sys_ioprio_set
	.long _sys_ioprio_get	/* 290 */
	.long _sys_inotify_init
	.long _sys_inotify_add_watch
	.long _sys_inotify_rm_watch
	.long _sys_ni_syscall /* migrate_pages */
	.long _sys_openat	/* 295 */
	.long _sys_mkdirat
	.long _sys_mknodat
	.long _sys_fchownat
	.long _sys_futimesat
	.long _sys_fstatat64	/* 300 */
	.long _sys_unlinkat
	.long _sys_renameat
	.long _sys_linkat
	.long _sys_symlinkat
	.long _sys_readlinkat	/* 305 */
	.long _sys_fchmodat
	.long _sys_faccessat
	.long _sys_pselect6
	.long _sys_ppoll
	.long _sys_unshare	/* 310 */
	.long _sys_sram_alloc
	.long _sys_sram_free
	.long _sys_dma_memcpy
	.long _sys_accept
	.long _sys_bind		/* 315 */
	.long _sys_connect
	.long _sys_getpeername
	.long _sys_getsockname
	.long _sys_getsockopt
	.long _sys_listen	/* 320 */
	.long _sys_recv
	.long _sys_recvfrom
	.long _sys_recvmsg
	.long _sys_send
	.long _sys_sendmsg	/* 325 */
	.long _sys_sendto
	.long _sys_setsockopt
	.long _sys_shutdown
	.long _sys_socket
	.long _sys_socketpair	/* 330 */
	.long _sys_semctl
	.long _sys_semget
	.long _sys_semop
	.long _sys_msgctl
	.long _sys_msgget	/* 335 */
	.long _sys_msgrcv
	.long _sys_msgsnd
	.long _sys_shmat
	.long _sys_shmctl
	.long _sys_shmdt	/* 340 */
	.long _sys_shmget
	.long _sys_splice
	.long _sys_sync_file_range
	.long _sys_tee
	.long _sys_vmsplice	/* 345 */
	.long _sys_epoll_pwait
	.long _sys_utimensat
	.long _sys_signalfd
	.long _sys_timerfd_create
	.long _sys_eventfd	/* 350 */
	.long _sys_pread64
	.long _sys_pwrite64
	.long _sys_fadvise64
	.long _sys_set_robust_list
	.long _sys_get_robust_list	/* 355 */
	.long _sys_fallocate
	.long _sys_semtimedop
	.long _sys_timerfd_settime
	.long _sys_timerfd_gettime
	.long _sys_signalfd4		/* 360 */
	.long _sys_eventfd2
	.long _sys_epoll_create1
	.long _sys_dup3
	.long _sys_pipe2
	.long _sys_inotify_init1	/* 365 */
	.long _sys_preadv
	.long _sys_pwritev
	.long _sys_rt_tgsigqueueinfo
	.long _sys_perf_event_open
	.long _sys_recvmmsg		/* 370 */
	.long _sys_fanotify_init
	.long _sys_fanotify_mark
	.long _sys_prlimit64
	.long _sys_cacheflush
	.long _sys_name_to_handle_at	/* 375 */
	.long _sys_open_by_handle_at
	.long _sys_clock_adjtime
	.long _sys_syncfs
	.long _sys_setns
	.long _sys_sendmmsg		/* 380 */
	.long _sys_process_vm_readv
	.long _sys_process_vm_writev

	.rept NR_syscalls-(.-_sys_call_table)/4
	.long _sys_ni_syscall
	.endr
END(_sys_call_table)