summaryrefslogtreecommitdiffstats
path: root/arch/x86_64/kernel/io_apic.c
blob: 0491019d4c8dc44204995cab7bf5eee7b1973c31 (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
1757
1758
1759
1760
1761
1762
1763
1764
1765
1766
1767
1768
1769
1770
1771
1772
1773
1774
1775
1776
1777
1778
1779
1780
1781
1782
1783
1784
1785
1786
1787
1788
1789
1790
1791
1792
1793
1794
1795
1796
1797
1798
1799
1800
1801
1802
1803
1804
1805
1806
1807
1808
1809
1810
1811
1812
1813
1814
1815
1816
1817
1818
1819
1820
1821
1822
1823
1824
1825
1826
1827
1828
1829
1830
1831
1832
1833
1834
1835
1836
1837
1838
1839
1840
1841
1842
1843
1844
1845
/*
 *	Intel IO-APIC support for multi-Pentium hosts.
 *
 *	Copyright (C) 1997, 1998, 1999, 2000 Ingo Molnar, Hajnalka Szabo
 *
 *	Many thanks to Stig Venaas for trying out countless experimental
 *	patches and reporting/debugging problems patiently!
 *
 *	(c) 1999, Multiple IO-APIC support, developed by
 *	Ken-ichi Yaku <yaku@css1.kbnes.nec.co.jp> and
 *      Hidemi Kishimoto <kisimoto@css1.kbnes.nec.co.jp>,
 *	further tested and cleaned up by Zach Brown <zab@redhat.com>
 *	and Ingo Molnar <mingo@redhat.com>
 *
 *	Fixes
 *	Maciej W. Rozycki	:	Bits for genuine 82489DX APICs;
 *					thanks to Eric Gilmore
 *					and Rolf G. Tews
 *					for testing these extensively
 *	Paul Diefenbaugh	:	Added full ACPI support
 */

#include <linux/mm.h>
#include <linux/interrupt.h>
#include <linux/init.h>
#include <linux/delay.h>
#include <linux/sched.h>
#include <linux/smp_lock.h>
#include <linux/mc146818rtc.h>
#include <linux/acpi.h>
#include <linux/sysdev.h>
#ifdef CONFIG_ACPI
#include <acpi/acpi_bus.h>
#endif

#include <asm/io.h>
#include <asm/smp.h>
#include <asm/desc.h>
#include <asm/proto.h>
#include <asm/mach_apic.h>
#include <asm/acpi.h>
#include <asm/dma.h>
#include <asm/nmi.h>

#define __apicdebuginit  __init

int sis_apic_bug; /* not actually supported, dummy for compile */

static int no_timer_check;

static int disable_timer_pin_1 __initdata;

int timer_over_8254 __initdata = 0;

/* Where if anywhere is the i8259 connect in external int mode */
static struct { int pin, apic; } ioapic_i8259 = { -1, -1 };

static DEFINE_SPINLOCK(ioapic_lock);
static DEFINE_SPINLOCK(vector_lock);

/*
 * # of IRQ routing registers
 */
int nr_ioapic_registers[MAX_IO_APICS];

/*
 * Rough estimation of how many shared IRQs there are, can
 * be changed anytime.
 */
#define MAX_PLUS_SHARED_IRQS NR_IRQ_VECTORS
#define PIN_MAP_SIZE (MAX_PLUS_SHARED_IRQS + NR_IRQS)

/*
 * This is performance-critical, we want to do it O(1)
 *
 * the indexing order of this array favors 1:1 mappings
 * between pins and IRQs.
 */

static struct irq_pin_list {
	short apic, pin, next;
} irq_2_pin[PIN_MAP_SIZE];

int vector_irq[NR_VECTORS] __read_mostly = { [0 ... NR_VECTORS - 1] = -1};
#ifdef CONFIG_PCI_MSI
#define vector_to_irq(vector) 	\
	(platform_legacy_irq(vector) ? vector : vector_irq[vector])
#else
#define vector_to_irq(vector)	(vector)
#endif

#define __DO_ACTION(R, ACTION, FINAL)					\
									\
{									\
	int pin;							\
	struct irq_pin_list *entry = irq_2_pin + irq;			\
									\
	BUG_ON(irq >= NR_IRQS);						\
	for (;;) {							\
		unsigned int reg;					\
		pin = entry->pin;					\
		if (pin == -1)						\
			break;						\
		reg = io_apic_read(entry->apic, 0x10 + R + pin*2);	\
		reg ACTION;						\
		io_apic_modify(entry->apic, reg);			\
		if (!entry->next)					\
			break;						\
		entry = irq_2_pin + entry->next;			\
	}								\
	FINAL;								\
}

union entry_union {
	struct { u32 w1, w2; };
	struct IO_APIC_route_entry entry;
};

static struct IO_APIC_route_entry ioapic_read_entry(int apic, int pin)
{
	union entry_union eu;
	unsigned long flags;
	spin_lock_irqsave(&ioapic_lock, flags);
	eu.w1 = io_apic_read(apic, 0x10 + 2 * pin);
	eu.w2 = io_apic_read(apic, 0x11 + 2 * pin);
	spin_unlock_irqrestore(&ioapic_lock, flags);
	return eu.entry;
}

static void ioapic_write_entry(int apic, int pin, struct IO_APIC_route_entry e)
{
	unsigned long flags;
	union entry_union eu;
	eu.entry = e;
	spin_lock_irqsave(&ioapic_lock, flags);
	io_apic_write(apic, 0x10 + 2*pin, eu.w1);
	io_apic_write(apic, 0x11 + 2*pin, eu.w2);
	spin_unlock_irqrestore(&ioapic_lock, flags);
}

#ifdef CONFIG_SMP
static void set_ioapic_affinity_irq(unsigned int irq, cpumask_t mask)
{
	unsigned long flags;
	unsigned int dest;
	cpumask_t tmp;

	cpus_and(tmp, mask, cpu_online_map);
	if (cpus_empty(tmp))
		tmp = TARGET_CPUS;

	cpus_and(mask, tmp, CPU_MASK_ALL);

	dest = cpu_mask_to_apicid(mask);

	/*
	 * Only the high 8 bits are valid.
	 */
	dest = SET_APIC_LOGICAL_ID(dest);

	spin_lock_irqsave(&ioapic_lock, flags);
	__DO_ACTION(1, = dest, )
	set_irq_info(irq, mask);
	spin_unlock_irqrestore(&ioapic_lock, flags);
}
#endif

static u8 gsi_2_irq[NR_IRQ_VECTORS] = { [0 ... NR_IRQ_VECTORS-1] = 0xFF };

/*
 * The common case is 1:1 IRQ<->pin mappings. Sometimes there are
 * shared ISA-space IRQs, so we have to support them. We are super
 * fast in the common case, and fast for shared ISA-space IRQs.
 */
static void add_pin_to_irq(unsigned int irq, int apic, int pin)
{
	static int first_free_entry = NR_IRQS;
	struct irq_pin_list *entry = irq_2_pin + irq;

	BUG_ON(irq >= NR_IRQS);
	while (entry->next)
		entry = irq_2_pin + entry->next;

	if (entry->pin != -1) {
		entry->next = first_free_entry;
		entry = irq_2_pin + entry->next;
		if (++first_free_entry >= PIN_MAP_SIZE)
			panic("io_apic.c: ran out of irq_2_pin entries!");
	}
	entry->apic = apic;
	entry->pin = pin;
}


#define DO_ACTION(name,R,ACTION, FINAL)					\
									\
	static void name##_IO_APIC_irq (unsigned int irq)		\
	__DO_ACTION(R, ACTION, FINAL)

DO_ACTION( __mask,             0, |= 0x00010000, io_apic_sync(entry->apic) )
						/* mask = 1 */
DO_ACTION( __unmask,           0, &= 0xfffeffff, )
						/* mask = 0 */

static void mask_IO_APIC_irq (unsigned int irq)
{
	unsigned long flags;

	spin_lock_irqsave(&ioapic_lock, flags);
	__mask_IO_APIC_irq(irq);
	spin_unlock_irqrestore(&ioapic_lock, flags);
}

static void unmask_IO_APIC_irq (unsigned int irq)
{
	unsigned long flags;

	spin_lock_irqsave(&ioapic_lock, flags);
	__unmask_IO_APIC_irq(irq);
	spin_unlock_irqrestore(&ioapic_lock, flags);
}

static void clear_IO_APIC_pin(unsigned int apic, unsigned int pin)
{
	struct IO_APIC_route_entry entry;

	/* Check delivery_mode to be sure we're not clearing an SMI pin */
	entry = ioapic_read_entry(apic, pin);
	if (entry.delivery_mode == dest_SMI)
		return;
	/*
	 * Disable it in the IO-APIC irq-routing table:
	 */
	memset(&entry, 0, sizeof(entry));
	entry.mask = 1;
	ioapic_write_entry(apic, pin, entry);
}

static void clear_IO_APIC (void)
{
	int apic, pin;

	for (apic = 0; apic < nr_ioapics; apic++)
		for (pin = 0; pin < nr_ioapic_registers[apic]; pin++)
			clear_IO_APIC_pin(apic, pin);
}

int skip_ioapic_setup;
int ioapic_force;

/* dummy parsing: see setup.c */

static int __init disable_ioapic_setup(char *str)
{
	skip_ioapic_setup = 1;
	return 0;
}
early_param("noapic", disable_ioapic_setup);

/* Actually the next is obsolete, but keep it for paranoid reasons -AK */
static int __init disable_timer_pin_setup(char *arg)
{
	disable_timer_pin_1 = 1;
	return 1;
}
__setup("disable_timer_pin_1", disable_timer_pin_setup);

static int __init setup_disable_8254_timer(char *s)
{
	timer_over_8254 = -1;
	return 1;
}
static int __init setup_enable_8254_timer(char *s)
{
	timer_over_8254 = 2;
	return 1;
}

__setup("disable_8254_timer", setup_disable_8254_timer);
__setup("enable_8254_timer", setup_enable_8254_timer);


/*
 * Find the IRQ entry number of a certain pin.
 */
static int find_irq_entry(int apic, int pin, int type)
{
	int i;

	for (i = 0; i < mp_irq_entries; i++)
		if (mp_irqs[i].mpc_irqtype == type &&
		    (mp_irqs[i].mpc_dstapic == mp_ioapics[apic].mpc_apicid ||
		     mp_irqs[i].mpc_dstapic == MP_APIC_ALL) &&
		    mp_irqs[i].mpc_dstirq == pin)
			return i;

	return -1;
}

/*
 * Find the pin to which IRQ[irq] (ISA) is connected
 */
static int __init find_isa_irq_pin(int irq, int type)
{
	int i;

	for (i = 0; i < mp_irq_entries; i++) {
		int lbus = mp_irqs[i].mpc_srcbus;

		if (test_bit(lbus, mp_bus_not_pci) &&
		    (mp_irqs[i].mpc_irqtype == type) &&
		    (mp_irqs[i].mpc_srcbusirq == irq))

			return mp_irqs[i].mpc_dstirq;
	}
	return -1;
}

static int __init find_isa_irq_apic(int irq, int type)
{
	int i;

	for (i = 0; i < mp_irq_entries; i++) {
		int lbus = mp_irqs[i].mpc_srcbus;

		if (test_bit(lbus, mp_bus_not_pci) &&
		    (mp_irqs[i].mpc_irqtype == type) &&
		    (mp_irqs[i].mpc_srcbusirq == irq))
			break;
	}
	if (i < mp_irq_entries) {
		int apic;
		for(apic = 0; apic < nr_ioapics; apic++) {
			if (mp_ioapics[apic].mpc_apicid == mp_irqs[i].mpc_dstapic)
				return apic;
		}
	}

	return -1;
}

/*
 * Find a specific PCI IRQ entry.
 * Not an __init, possibly needed by modules
 */
static int pin_2_irq(int idx, int apic, int pin);

int IO_APIC_get_PCI_irq_vector(int bus, int slot, int pin)
{
	int apic, i, best_guess = -1;

	apic_printk(APIC_DEBUG, "querying PCI -> IRQ mapping bus:%d, slot:%d, pin:%d.\n",
		bus, slot, pin);
	if (mp_bus_id_to_pci_bus[bus] == -1) {
		apic_printk(APIC_VERBOSE, "PCI BIOS passed nonexistent PCI bus %d!\n", bus);
		return -1;
	}
	for (i = 0; i < mp_irq_entries; i++) {
		int lbus = mp_irqs[i].mpc_srcbus;

		for (apic = 0; apic < nr_ioapics; apic++)
			if (mp_ioapics[apic].mpc_apicid == mp_irqs[i].mpc_dstapic ||
			    mp_irqs[i].mpc_dstapic == MP_APIC_ALL)
				break;

		if (!test_bit(lbus, mp_bus_not_pci) &&
		    !mp_irqs[i].mpc_irqtype &&
		    (bus == lbus) &&
		    (slot == ((mp_irqs[i].mpc_srcbusirq >> 2) & 0x1f))) {
			int irq = pin_2_irq(i,apic,mp_irqs[i].mpc_dstirq);

			if (!(apic || IO_APIC_IRQ(irq)))
				continue;

			if (pin == (mp_irqs[i].mpc_srcbusirq & 3))
				return irq;
			/*
			 * Use the first all-but-pin matching entry as a
			 * best-guess fuzzy result for broken mptables.
			 */
			if (best_guess < 0)
				best_guess = irq;
		}
	}
	BUG_ON(best_guess >= NR_IRQS);
	return best_guess;
}

/* ISA interrupts are always polarity zero edge triggered,
 * when listed as conforming in the MP table. */

#define default_ISA_trigger(idx)	(0)
#define default_ISA_polarity(idx)	(0)

/* PCI interrupts are always polarity one level triggered,
 * when listed as conforming in the MP table. */

#define default_PCI_trigger(idx)	(1)
#define default_PCI_polarity(idx)	(1)

static int __init MPBIOS_polarity(int idx)
{
	int bus = mp_irqs[idx].mpc_srcbus;
	int polarity;

	/*
	 * Determine IRQ line polarity (high active or low active):
	 */
	switch (mp_irqs[idx].mpc_irqflag & 3)
	{
		case 0: /* conforms, ie. bus-type dependent polarity */
			if (test_bit(bus, mp_bus_not_pci))
				polarity = default_ISA_polarity(idx);
			else
				polarity = default_PCI_polarity(idx);
			break;
		case 1: /* high active */
		{
			polarity = 0;
			break;
		}
		case 2: /* reserved */
		{
			printk(KERN_WARNING "broken BIOS!!\n");
			polarity = 1;
			break;
		}
		case 3: /* low active */
		{
			polarity = 1;
			break;
		}
		default: /* invalid */
		{
			printk(KERN_WARNING "broken BIOS!!\n");
			polarity = 1;
			break;
		}
	}
	return polarity;
}

static int MPBIOS_trigger(int idx)
{
	int bus = mp_irqs[idx].mpc_srcbus;
	int trigger;

	/*
	 * Determine IRQ trigger mode (edge or level sensitive):
	 */
	switch ((mp_irqs[idx].mpc_irqflag>>2) & 3)
	{
		case 0: /* conforms, ie. bus-type dependent */
			if (test_bit(bus, mp_bus_not_pci))
				trigger = default_ISA_trigger(idx);
			else
				trigger = default_PCI_trigger(idx);
			break;
		case 1: /* edge */
		{
			trigger = 0;
			break;
		}
		case 2: /* reserved */
		{
			printk(KERN_WARNING "broken BIOS!!\n");
			trigger = 1;
			break;
		}
		case 3: /* level */
		{
			trigger = 1;
			break;
		}
		default: /* invalid */
		{
			printk(KERN_WARNING "broken BIOS!!\n");
			trigger = 0;
			break;
		}
	}
	return trigger;
}

static inline int irq_polarity(int idx)
{
	return MPBIOS_polarity(idx);
}

static inline int irq_trigger(int idx)
{
	return MPBIOS_trigger(idx);
}

static int next_irq = 16;

/*
 * gsi_irq_sharing -- Name overload!  "irq" can be either a legacy IRQ
 * in the range 0-15, a linux IRQ in the range 0-223, or a GSI number
 * from ACPI, which can reach 800 in large boxen.
 *
 * Compact the sparse GSI space into a sequential IRQ series and reuse
 * vectors if possible.
 */
int gsi_irq_sharing(int gsi)
{
	int i, tries, vector;

	BUG_ON(gsi >= NR_IRQ_VECTORS);

	if (platform_legacy_irq(gsi))
		return gsi;

	if (gsi_2_irq[gsi] != 0xFF)
		return (int)gsi_2_irq[gsi];

	tries = NR_IRQS;
  try_again:
	vector = assign_irq_vector(gsi);

	/*
	 * Sharing vectors means sharing IRQs, so scan irq_vectors for previous
	 * use of vector and if found, return that IRQ.  However, we never want
	 * to share legacy IRQs, which usually have a different trigger mode
	 * than PCI.
	 */
	for (i = 0; i < NR_IRQS; i++)
		if (IO_APIC_VECTOR(i) == vector)
			break;
	if (platform_legacy_irq(i)) {
		if (--tries >= 0) {
			IO_APIC_VECTOR(i) = 0;
			goto try_again;
		}
		panic("gsi_irq_sharing: didn't find an IRQ using vector 0x%02X for GSI %d", vector, gsi);
	}
	if (i < NR_IRQS) {
		gsi_2_irq[gsi] = i;
		printk(KERN_INFO "GSI %d sharing vector 0x%02X and IRQ %d\n",
				gsi, vector, i);
		return i;
	}

	i = next_irq++;
	BUG_ON(i >= NR_IRQS);
	gsi_2_irq[gsi] = i;
	IO_APIC_VECTOR(i) = vector;
	printk(KERN_INFO "GSI %d assigned vector 0x%02X and IRQ %d\n",
			gsi, vector, i);
	return i;
}

static int pin_2_irq(int idx, int apic, int pin)
{
	int irq, i;
	int bus = mp_irqs[idx].mpc_srcbus;

	/*
	 * Debugging check, we are in big trouble if this message pops up!
	 */
	if (mp_irqs[idx].mpc_dstirq != pin)
		printk(KERN_ERR "broken BIOS or MPTABLE parser, ayiee!!\n");

	if (test_bit(bus, mp_bus_not_pci)) {
		irq = mp_irqs[idx].mpc_srcbusirq;
	} else {
		/*
		 * PCI IRQs are mapped in order
		 */
		i = irq = 0;
		while (i < apic)
			irq += nr_ioapic_registers[i++];
		irq += pin;
		irq = gsi_irq_sharing(irq);
	}
	BUG_ON(irq >= NR_IRQS);
	return irq;
}

static inline int IO_APIC_irq_trigger(int irq)
{
	int apic, idx, pin;

	for (apic = 0; apic < nr_ioapics; apic++) {
		for (pin = 0; pin < nr_ioapic_registers[apic]; pin++) {
			idx = find_irq_entry(apic,pin,mp_INT);
			if ((idx != -1) && (irq == pin_2_irq(idx,apic,pin)))
				return irq_trigger(idx);
		}
	}
	/*
	 * nonexistent IRQs are edge default
	 */
	return 0;
}

/* irq_vectors is indexed by the sum of all RTEs in all I/O APICs. */
u8 irq_vector[NR_IRQ_VECTORS] __read_mostly = { FIRST_DEVICE_VECTOR , 0 };

int assign_irq_vector(int irq)
{
	static int current_vector = FIRST_DEVICE_VECTOR, offset = 0;
	unsigned long flags;
	int vector;

	BUG_ON(irq != AUTO_ASSIGN && (unsigned)irq >= NR_IRQ_VECTORS);

	spin_lock_irqsave(&vector_lock, flags);

	if (irq != AUTO_ASSIGN && IO_APIC_VECTOR(irq) > 0) {
		spin_unlock_irqrestore(&vector_lock, flags);
		return IO_APIC_VECTOR(irq);
	}
next:
	current_vector += 8;
	if (current_vector == IA32_SYSCALL_VECTOR)
		goto next;

	if (current_vector >= FIRST_SYSTEM_VECTOR) {
		/* If we run out of vectors on large boxen, must share them. */
		offset = (offset + 1) % 8;
		current_vector = FIRST_DEVICE_VECTOR + offset;
	}

	vector = current_vector;
	vector_irq[vector] = irq;
	if (irq != AUTO_ASSIGN)
		IO_APIC_VECTOR(irq) = vector;

	spin_unlock_irqrestore(&vector_lock, flags);

	return vector;
}

extern void (*interrupt[NR_IRQS])(void);
static struct hw_interrupt_type ioapic_level_type;
static struct hw_interrupt_type ioapic_edge_type;

#define IOAPIC_AUTO	-1
#define IOAPIC_EDGE	0
#define IOAPIC_LEVEL	1

static void ioapic_register_intr(int irq, int vector, unsigned long trigger)
{
	unsigned idx;

	idx = use_pci_vector() && !platform_legacy_irq(irq) ? vector : irq;

	if ((trigger == IOAPIC_AUTO && IO_APIC_irq_trigger(irq)) ||
			trigger == IOAPIC_LEVEL)
		irq_desc[idx].chip = &ioapic_level_type;
	else
		irq_desc[idx].chip = &ioapic_edge_type;
	set_intr_gate(vector, interrupt[idx]);
}

static void __init setup_IO_APIC_irqs(void)
{
	struct IO_APIC_route_entry entry;
	int apic, pin, idx, irq, first_notcon = 1, vector;
	unsigned long flags;

	apic_printk(APIC_VERBOSE, KERN_DEBUG "init IO_APIC IRQs\n");

	for (apic = 0; apic < nr_ioapics; apic++) {
	for (pin = 0; pin < nr_ioapic_registers[apic]; pin++) {

		/*
		 * add it to the IO-APIC irq-routing table:
		 */
		memset(&entry,0,sizeof(entry));

		entry.delivery_mode = INT_DELIVERY_MODE;
		entry.dest_mode = INT_DEST_MODE;
		entry.mask = 0;				/* enable IRQ */
		entry.dest.logical.logical_dest = cpu_mask_to_apicid(TARGET_CPUS);

		idx = find_irq_entry(apic,pin,mp_INT);
		if (idx == -1) {
			if (first_notcon) {
				apic_printk(APIC_VERBOSE, KERN_DEBUG " IO-APIC (apicid-pin) %d-%d", mp_ioapics[apic].mpc_apicid, pin);
				first_notcon = 0;
			} else
				apic_printk(APIC_VERBOSE, ", %d-%d", mp_ioapics[apic].mpc_apicid, pin);
			continue;
		}

		entry.trigger = irq_trigger(idx);
		entry.polarity = irq_polarity(idx);

		if (irq_trigger(idx)) {
			entry.trigger = 1;
			entry.mask = 1;
			entry.dest.logical.logical_dest = cpu_mask_to_apicid(TARGET_CPUS);
		}

		irq = pin_2_irq(idx, apic, pin);
		add_pin_to_irq(irq, apic, pin);

		if (!apic && !IO_APIC_IRQ(irq))
			continue;

		if (IO_APIC_IRQ(irq)) {
			vector = assign_irq_vector(irq);
			entry.vector = vector;

			ioapic_register_intr(irq, vector, IOAPIC_AUTO);
			if (!apic && (irq < 16))
				disable_8259A_irq(irq);
		}
		ioapic_write_entry(apic, pin, entry);

		spin_lock_irqsave(&ioapic_lock, flags);
		set_native_irq_info(irq, TARGET_CPUS);
		spin_unlock_irqrestore(&ioapic_lock, flags);
	}
	}

	if (!first_notcon)
		apic_printk(APIC_VERBOSE," not connected.\n");
}

/*
 * Set up the 8259A-master output pin as broadcast to all
 * CPUs.
 */
static void __init setup_ExtINT_IRQ0_pin(unsigned int apic, unsigned int pin, int vector)
{
	struct IO_APIC_route_entry entry;
	unsigned long flags;

	memset(&entry,0,sizeof(entry));

	disable_8259A_irq(0);

	/* mask LVT0 */
	apic_write(APIC_LVT0, APIC_LVT_MASKED | APIC_DM_EXTINT);

	/*
	 * We use logical delivery to get the timer IRQ
	 * to the first CPU.
	 */
	entry.dest_mode = INT_DEST_MODE;
	entry.mask = 0;					/* unmask IRQ now */
	entry.dest.logical.logical_dest = cpu_mask_to_apicid(TARGET_CPUS);
	entry.delivery_mode = INT_DELIVERY_MODE;
	entry.polarity = 0;
	entry.trigger = 0;
	entry.vector = vector;

	/*
	 * The timer IRQ doesn't have to know that behind the
	 * scene we have a 8259A-master in AEOI mode ...
	 */
	irq_desc[0].chip = &ioapic_edge_type;

	/*
	 * Add it to the IO-APIC irq-routing table:
	 */
	spin_lock_irqsave(&ioapic_lock, flags);
	io_apic_write(apic, 0x11+2*pin, *(((int *)&entry)+1));
	io_apic_write(apic, 0x10+2*pin, *(((int *)&entry)+0));
	spin_unlock_irqrestore(&ioapic_lock, flags);

	enable_8259A_irq(0);
}

void __init UNEXPECTED_IO_APIC(void)
{
}

void __apicdebuginit print_IO_APIC(void)
{
	int apic, i;
	union IO_APIC_reg_00 reg_00;
	union IO_APIC_reg_01 reg_01;
	union IO_APIC_reg_02 reg_02;
	unsigned long flags;

	if (apic_verbosity == APIC_QUIET)
		return;

	printk(KERN_DEBUG "number of MP IRQ sources: %d.\n", mp_irq_entries);
	for (i = 0; i < nr_ioapics; i++)
		printk(KERN_DEBUG "number of IO-APIC #%d registers: %d.\n",
		       mp_ioapics[i].mpc_apicid, nr_ioapic_registers[i]);

	/*
	 * We are a bit conservative about what we expect.  We have to
	 * know about every hardware change ASAP.
	 */
	printk(KERN_INFO "testing the IO APIC.......................\n");

	for (apic = 0; apic < nr_ioapics; apic++) {

	spin_lock_irqsave(&ioapic_lock, flags);
	reg_00.raw = io_apic_read(apic, 0);
	reg_01.raw = io_apic_read(apic, 1);
	if (reg_01.bits.version >= 0x10)
		reg_02.raw = io_apic_read(apic, 2);
	spin_unlock_irqrestore(&ioapic_lock, flags);

	printk("\n");
	printk(KERN_DEBUG "IO APIC #%d......\n", mp_ioapics[apic].mpc_apicid);
	printk(KERN_DEBUG ".... register #00: %08X\n", reg_00.raw);
	printk(KERN_DEBUG ".......    : physical APIC id: %02X\n", reg_00.bits.ID);
	if (reg_00.bits.__reserved_1 || reg_00.bits.__reserved_2)
		UNEXPECTED_IO_APIC();

	printk(KERN_DEBUG ".... register #01: %08X\n", *(int *)&reg_01);
	printk(KERN_DEBUG ".......     : max redirection entries: %04X\n", reg_01.bits.entries);
	if (	(reg_01.bits.entries != 0x0f) && /* older (Neptune) boards */
		(reg_01.bits.entries != 0x17) && /* typical ISA+PCI boards */
		(reg_01.bits.entries != 0x1b) && /* Compaq Proliant boards */
		(reg_01.bits.entries != 0x1f) && /* dual Xeon boards */
		(reg_01.bits.entries != 0x22) && /* bigger Xeon boards */
		(reg_01.bits.entries != 0x2E) &&
		(reg_01.bits.entries != 0x3F) &&
		(reg_01.bits.entries != 0x03) 
	)
		UNEXPECTED_IO_APIC();

	printk(KERN_DEBUG ".......     : PRQ implemented: %X\n", reg_01.bits.PRQ);
	printk(KERN_DEBUG ".......     : IO APIC version: %04X\n", reg_01.bits.version);
	if (	(reg_01.bits.version != 0x01) && /* 82489DX IO-APICs */
		(reg_01.bits.version != 0x02) && /* 82801BA IO-APICs (ICH2) */
		(reg_01.bits.version != 0x10) && /* oldest IO-APICs */
		(reg_01.bits.version != 0x11) && /* Pentium/Pro IO-APICs */
		(reg_01.bits.version != 0x13) && /* Xeon IO-APICs */
		(reg_01.bits.version != 0x20)    /* Intel P64H (82806 AA) */
	)
		UNEXPECTED_IO_APIC();
	if (reg_01.bits.__reserved_1 || reg_01.bits.__reserved_2)
		UNEXPECTED_IO_APIC();

	if (reg_01.bits.version >= 0x10) {
		printk(KERN_DEBUG ".... register #02: %08X\n", reg_02.raw);
		printk(KERN_DEBUG ".......     : arbitration: %02X\n", reg_02.bits.arbitration);
		if (reg_02.bits.__reserved_1 || reg_02.bits.__reserved_2)
			UNEXPECTED_IO_APIC();
	}

	printk(KERN_DEBUG ".... IRQ redirection table:\n");

	printk(KERN_DEBUG " NR Log Phy Mask Trig IRR Pol"
			  " Stat Dest Deli Vect:   \n");

	for (i = 0; i <= reg_01.bits.entries; i++) {
		struct IO_APIC_route_entry entry;

		entry = ioapic_read_entry(apic, i);

		printk(KERN_DEBUG " %02x %03X %02X  ",
			i,
			entry.dest.logical.logical_dest,
			entry.dest.physical.physical_dest
		);

		printk("%1d    %1d    %1d   %1d   %1d    %1d    %1d    %02X\n",
			entry.mask,
			entry.trigger,
			entry.irr,
			entry.polarity,
			entry.delivery_status,
			entry.dest_mode,
			entry.delivery_mode,
			entry.vector
		);
	}
	}
	if (use_pci_vector())
		printk(KERN_INFO "Using vector-based indexing\n");
	printk(KERN_DEBUG "IRQ to pin mappings:\n");
	for (i = 0; i < NR_IRQS; i++) {
		struct irq_pin_list *entry = irq_2_pin + i;
		if (entry->pin < 0)
			continue;
 		if (use_pci_vector() && !platform_legacy_irq(i))
			printk(KERN_DEBUG "IRQ%d ", IO_APIC_VECTOR(i));
		else
			printk(KERN_DEBUG "IRQ%d ", i);
		for (;;) {
			printk("-> %d:%d", entry->apic, entry->pin);
			if (!entry->next)
				break;
			entry = irq_2_pin + entry->next;
		}
		printk("\n");
	}

	printk(KERN_INFO ".................................... done.\n");

	return;
}

#if 0

static __apicdebuginit void print_APIC_bitfield (int base)
{
	unsigned int v;
	int i, j;

	if (apic_verbosity == APIC_QUIET)
		return;

	printk(KERN_DEBUG "0123456789abcdef0123456789abcdef\n" KERN_DEBUG);
	for (i = 0; i < 8; i++) {
		v = apic_read(base + i*0x10);
		for (j = 0; j < 32; j++) {
			if (v & (1<<j))
				printk("1");
			else
				printk("0");
		}
		printk("\n");
	}
}

void __apicdebuginit print_local_APIC(void * dummy)
{
	unsigned int v, ver, maxlvt;

	if (apic_verbosity == APIC_QUIET)
		return;

	printk("\n" KERN_DEBUG "printing local APIC contents on CPU#%d/%d:\n",
		smp_processor_id(), hard_smp_processor_id());
	v = apic_read(APIC_ID);
	printk(KERN_INFO "... APIC ID:      %08x (%01x)\n", v, GET_APIC_ID(v));
	v = apic_read(APIC_LVR);
	printk(KERN_INFO "... APIC VERSION: %08x\n", v);
	ver = GET_APIC_VERSION(v);
	maxlvt = get_maxlvt();

	v = apic_read(APIC_TASKPRI);
	printk(KERN_DEBUG "... APIC TASKPRI: %08x (%02x)\n", v, v & APIC_TPRI_MASK);

	v = apic_read(APIC_ARBPRI);
	printk(KERN_DEBUG "... APIC ARBPRI: %08x (%02x)\n", v,
		v & APIC_ARBPRI_MASK);
	v = apic_read(APIC_PROCPRI);
	printk(KERN_DEBUG "... APIC PROCPRI: %08x\n", v);

	v = apic_read(APIC_EOI);
	printk(KERN_DEBUG "... APIC EOI: %08x\n", v);
	v = apic_read(APIC_RRR);
	printk(KERN_DEBUG "... APIC RRR: %08x\n", v);
	v = apic_read(APIC_LDR);
	printk(KERN_DEBUG "... APIC LDR: %08x\n", v);
	v = apic_read(APIC_DFR);
	printk(KERN_DEBUG "... APIC DFR: %08x\n", v);
	v = apic_read(APIC_SPIV);
	printk(KERN_DEBUG "... APIC SPIV: %08x\n", v);

	printk(KERN_DEBUG "... APIC ISR field:\n");
	print_APIC_bitfield(APIC_ISR);
	printk(KERN_DEBUG "... APIC TMR field:\n");
	print_APIC_bitfield(APIC_TMR);
	printk(KERN_DEBUG "... APIC IRR field:\n");
	print_APIC_bitfield(APIC_IRR);

	v = apic_read(APIC_ESR);
	printk(KERN_DEBUG "... APIC ESR: %08x\n", v);

	v = apic_read(APIC_ICR);
	printk(KERN_DEBUG "... APIC ICR: %08x\n", v);
	v = apic_read(APIC_ICR2);
	printk(KERN_DEBUG "... APIC ICR2: %08x\n", v);

	v = apic_read(APIC_LVTT);
	printk(KERN_DEBUG "... APIC LVTT: %08x\n", v);

	if (maxlvt > 3) {                       /* PC is LVT#4. */
		v = apic_read(APIC_LVTPC);
		printk(KERN_DEBUG "... APIC LVTPC: %08x\n", v);
	}
	v = apic_read(APIC_LVT0);
	printk(KERN_DEBUG "... APIC LVT0: %08x\n", v);
	v = apic_read(APIC_LVT1);
	printk(KERN_DEBUG "... APIC LVT1: %08x\n", v);

	if (maxlvt > 2) {			/* ERR is LVT#3. */
		v = apic_read(APIC_LVTERR);
		printk(KERN_DEBUG "... APIC LVTERR: %08x\n", v);
	}

	v = apic_read(APIC_TMICT);
	printk(KERN_DEBUG "... APIC TMICT: %08x\n", v);
	v = apic_read(APIC_TMCCT);
	printk(KERN_DEBUG "... APIC TMCCT: %08x\n", v);
	v = apic_read(APIC_TDCR);
	printk(KERN_DEBUG "... APIC TDCR: %08x\n", v);
	printk("\n");
}

void print_all_local_APICs (void)
{
	on_each_cpu(print_local_APIC, NULL, 1, 1);
}

void __apicdebuginit print_PIC(void)
{
	unsigned int v;
	unsigned long flags;

	if (apic_verbosity == APIC_QUIET)
		return;

	printk(KERN_DEBUG "\nprinting PIC contents\n");

	spin_lock_irqsave(&i8259A_lock, flags);

	v = inb(0xa1) << 8 | inb(0x21);
	printk(KERN_DEBUG "... PIC  IMR: %04x\n", v);

	v = inb(0xa0) << 8 | inb(0x20);
	printk(KERN_DEBUG "... PIC  IRR: %04x\n", v);

	outb(0x0b,0xa0);
	outb(0x0b,0x20);
	v = inb(0xa0) << 8 | inb(0x20);
	outb(0x0a,0xa0);
	outb(0x0a,0x20);

	spin_unlock_irqrestore(&i8259A_lock, flags);

	printk(KERN_DEBUG "... PIC  ISR: %04x\n", v);

	v = inb(0x4d1) << 8 | inb(0x4d0);
	printk(KERN_DEBUG "... PIC ELCR: %04x\n", v);
}

#endif  /*  0  */

static void __init enable_IO_APIC(void)
{
	union IO_APIC_reg_01 reg_01;
	int i8259_apic, i8259_pin;
	int i, apic;
	unsigned long flags;

	for (i = 0; i < PIN_MAP_SIZE; i++) {
		irq_2_pin[i].pin = -1;
		irq_2_pin[i].next = 0;
	}

	/*
	 * The number of IO-APIC IRQ registers (== #pins):
	 */
	for (apic = 0; apic < nr_ioapics; apic++) {
		spin_lock_irqsave(&ioapic_lock, flags);
		reg_01.raw = io_apic_read(apic, 1);
		spin_unlock_irqrestore(&ioapic_lock, flags);
		nr_ioapic_registers[apic] = reg_01.bits.entries+1;
	}
	for(apic = 0; apic < nr_ioapics; apic++) {
		int pin;
		/* See if any of the pins is in ExtINT mode */
		for (pin = 0; pin < nr_ioapic_registers[apic]; pin++) {
			struct IO_APIC_route_entry entry;
			entry = ioapic_read_entry(apic, pin);

			/* If the interrupt line is enabled and in ExtInt mode
			 * I have found the pin where the i8259 is connected.
			 */
			if ((entry.mask == 0) && (entry.delivery_mode == dest_ExtINT)) {
				ioapic_i8259.apic = apic;
				ioapic_i8259.pin  = pin;
				goto found_i8259;
			}
		}
	}
 found_i8259:
	/* Look to see what if the MP table has reported the ExtINT */
	i8259_pin  = find_isa_irq_pin(0, mp_ExtINT);
	i8259_apic = find_isa_irq_apic(0, mp_ExtINT);
	/* Trust the MP table if nothing is setup in the hardware */
	if ((ioapic_i8259.pin == -1) && (i8259_pin >= 0)) {
		printk(KERN_WARNING "ExtINT not setup in hardware but reported by MP table\n");
		ioapic_i8259.pin  = i8259_pin;
		ioapic_i8259.apic = i8259_apic;
	}
	/* Complain if the MP table and the hardware disagree */
	if (((ioapic_i8259.apic != i8259_apic) || (ioapic_i8259.pin != i8259_pin)) &&
		(i8259_pin >= 0) && (ioapic_i8259.pin >= 0))
	{
		printk(KERN_WARNING "ExtINT in hardware and MP table differ\n");
	}

	/*
	 * Do not trust the IO-APIC being empty at bootup
	 */
	clear_IO_APIC();
}

/*
 * Not an __init, needed by the reboot code
 */
void disable_IO_APIC(void)
{
	/*
	 * Clear the IO-APIC before rebooting:
	 */
	clear_IO_APIC();

	/*
	 * If the i8259 is routed through an IOAPIC
	 * Put that IOAPIC in virtual wire mode
	 * so legacy interrupts can be delivered.
	 */
	if (ioapic_i8259.pin != -1) {
		struct IO_APIC_route_entry entry;

		memset(&entry, 0, sizeof(entry));
		entry.mask            = 0; /* Enabled */
		entry.trigger         = 0; /* Edge */
		entry.irr             = 0;
		entry.polarity        = 0; /* High */
		entry.delivery_status = 0;
		entry.dest_mode       = 0; /* Physical */
		entry.delivery_mode   = dest_ExtINT; /* ExtInt */
		entry.vector          = 0;
		entry.dest.physical.physical_dest =
					GET_APIC_ID(apic_read(APIC_ID));

		/*
		 * Add it to the IO-APIC irq-routing table:
		 */
		ioapic_write_entry(ioapic_i8259.apic, ioapic_i8259.pin, entry);
	}

	disconnect_bsp_APIC(ioapic_i8259.pin != -1);
}

/*
 * There is a nasty bug in some older SMP boards, their mptable lies
 * about the timer IRQ. We do the following to work around the situation:
 *
 *	- timer IRQ defaults to IO-APIC IRQ
 *	- if this function detects that timer IRQs are defunct, then we fall
 *	  back to ISA timer IRQs
 */
static int __init timer_irq_works(void)
{
	unsigned long t1 = jiffies;

	local_irq_enable();
	/* Let ten ticks pass... */
	mdelay((10 * 1000) / HZ);

	/*
	 * Expect a few ticks at least, to be sure some possible
	 * glue logic does not lock up after one or two first
	 * ticks in a non-ExtINT mode.  Also the local APIC
	 * might have cached one ExtINT interrupt.  Finally, at
	 * least one tick may be lost due to delays.
	 */

	/* jiffies wrap? */
	if (jiffies - t1 > 4)
		return 1;
	return 0;
}

/*
 * In the SMP+IOAPIC case it might happen that there are an unspecified
 * number of pending IRQ events unhandled. These cases are very rare,
 * so we 'resend' these IRQs via IPIs, to the same CPU. It's much
 * better to do it this way as thus we do not have to be aware of
 * 'pending' interrupts in the IRQ path, except at this point.
 */
/*
 * Edge triggered needs to resend any interrupt
 * that was delayed but this is now handled in the device
 * independent code.
 */

/*
 * Starting up a edge-triggered IO-APIC interrupt is
 * nasty - we need to make sure that we get the edge.
 * If it is already asserted for some reason, we need
 * return 1 to indicate that is was pending.
 *
 * This is not complete - we should be able to fake
 * an edge even if it isn't on the 8259A...
 */

static unsigned int startup_edge_ioapic_irq(unsigned int irq)
{
	int was_pending = 0;
	unsigned long flags;

	spin_lock_irqsave(&ioapic_lock, flags);
	if (irq < 16) {
		disable_8259A_irq(irq);
		if (i8259A_irq_pending(irq))
			was_pending = 1;
	}
	__unmask_IO_APIC_irq(irq);
	spin_unlock_irqrestore(&ioapic_lock, flags);

	return was_pending;
}

/*
 * Once we have recorded IRQ_PENDING already, we can mask the
 * interrupt for real. This prevents IRQ storms from unhandled
 * devices.
 */
static void ack_edge_ioapic_irq(unsigned int irq)
{
	move_irq(irq);
	if ((irq_desc[irq].status & (IRQ_PENDING | IRQ_DISABLED))
					== (IRQ_PENDING | IRQ_DISABLED))
		mask_IO_APIC_irq(irq);
	ack_APIC_irq();
}

/*
 * Level triggered interrupts can just be masked,
 * and shutting down and starting up the interrupt
 * is the same as enabling and disabling them -- except
 * with a startup need to return a "was pending" value.
 *
 * Level triggered interrupts are special because we
 * do not touch any IO-APIC register while handling
 * them. We ack the APIC in the end-IRQ handler, not
 * in the start-IRQ-handler. Protection against reentrance
 * from the same interrupt is still provided, both by the
 * generic IRQ layer and by the fact that an unacked local
 * APIC does not accept IRQs.
 */
static unsigned int startup_level_ioapic_irq (unsigned int irq)
{
	unmask_IO_APIC_irq(irq);

	return 0; /* don't check for pending */
}

static void end_level_ioapic_irq (unsigned int irq)
{
	move_irq(irq);
	ack_APIC_irq();
}

#ifdef CONFIG_PCI_MSI
static unsigned int startup_edge_ioapic_vector(unsigned int vector)
{
	int irq = vector_to_irq(vector);

	return startup_edge_ioapic_irq(irq);
}

static void ack_edge_ioapic_vector(unsigned int vector)
{
	int irq = vector_to_irq(vector);

	move_native_irq(vector);
	ack_edge_ioapic_irq(irq);
}

static unsigned int startup_level_ioapic_vector (unsigned int vector)
{
	int irq = vector_to_irq(vector);

	return startup_level_ioapic_irq (irq);
}

static void end_level_ioapic_vector (unsigned int vector)
{
	int irq = vector_to_irq(vector);

	move_native_irq(vector);
	end_level_ioapic_irq(irq);
}

static void mask_IO_APIC_vector (unsigned int vector)
{
	int irq = vector_to_irq(vector);

	mask_IO_APIC_irq(irq);
}

static void unmask_IO_APIC_vector (unsigned int vector)
{
	int irq = vector_to_irq(vector);

	unmask_IO_APIC_irq(irq);
}

#ifdef CONFIG_SMP
static void set_ioapic_affinity_vector (unsigned int vector,
					cpumask_t cpu_mask)
{
	int irq = vector_to_irq(vector);

	set_native_irq_info(vector, cpu_mask);
	set_ioapic_affinity_irq(irq, cpu_mask);
}
#endif // CONFIG_SMP
#endif // CONFIG_PCI_MSI

static int ioapic_retrigger(unsigned int irq)
{
	send_IPI_self(IO_APIC_VECTOR(irq));

	return 1;
}

/*
 * Level and edge triggered IO-APIC interrupts need different handling,
 * so we use two separate IRQ descriptors. Edge triggered IRQs can be
 * handled with the level-triggered descriptor, but that one has slightly
 * more overhead. Level-triggered interrupts cannot be handled with the
 * edge-triggered handler, without risking IRQ storms and other ugly
 * races.
 */

static struct hw_interrupt_type ioapic_edge_type __read_mostly = {
	.typename = "IO-APIC-edge",
	.startup 	= startup_edge_ioapic,
	.shutdown 	= shutdown_edge_ioapic,
	.enable 	= enable_edge_ioapic,
	.disable 	= disable_edge_ioapic,
	.ack 		= ack_edge_ioapic,
	.end 		= end_edge_ioapic,
#ifdef CONFIG_SMP
	.set_affinity = set_ioapic_affinity,
#endif
	.retrigger	= ioapic_retrigger,
};

static struct hw_interrupt_type ioapic_level_type __read_mostly = {
	.typename = "IO-APIC-level",
	.startup 	= startup_level_ioapic,
	.shutdown 	= shutdown_level_ioapic,
	.enable 	= enable_level_ioapic,
	.disable 	= disable_level_ioapic,
	.ack 		= mask_and_ack_level_ioapic,
	.end 		= end_level_ioapic,
#ifdef CONFIG_SMP
	.set_affinity = set_ioapic_affinity,
#endif
	.retrigger	= ioapic_retrigger,
};

static inline void init_IO_APIC_traps(void)
{
	int irq;

	/*
	 * NOTE! The local APIC isn't very good at handling
	 * multiple interrupts at the same interrupt level.
	 * As the interrupt level is determined by taking the
	 * vector number and shifting that right by 4, we
	 * want to spread these out a bit so that they don't
	 * all fall in the same interrupt level.
	 *
	 * Also, we've got to be careful not to trash gate
	 * 0x80, because int 0x80 is hm, kind of importantish. ;)
	 */
	for (irq = 0; irq < NR_IRQS ; irq++) {
		int tmp = irq;
		if (use_pci_vector()) {
			if (!platform_legacy_irq(tmp))
				if ((tmp = vector_to_irq(tmp)) == -1)
					continue;
		}
		if (IO_APIC_IRQ(tmp) && !IO_APIC_VECTOR(tmp)) {
			/*
			 * Hmm.. We don't have an entry for this,
			 * so default to an old-fashioned 8259
			 * interrupt if we can..
			 */
			if (irq < 16)
				make_8259A_irq(irq);
			else
				/* Strange. Oh, well.. */
				irq_desc[irq].chip = &no_irq_type;
		}
	}
}

static void enable_lapic_irq (unsigned int irq)
{
	unsigned long v;

	v = apic_read(APIC_LVT0);
	apic_write(APIC_LVT0, v & ~APIC_LVT_MASKED);
}

static void disable_lapic_irq (unsigned int irq)
{
	unsigned long v;

	v = apic_read(APIC_LVT0);
	apic_write(APIC_LVT0, v | APIC_LVT_MASKED);
}

static void ack_lapic_irq (unsigned int irq)
{
	ack_APIC_irq();
}

static void end_lapic_irq (unsigned int i) { /* nothing */ }

static struct hw_interrupt_type lapic_irq_type __read_mostly = {
	.typename = "local-APIC-edge",
	.startup = NULL, /* startup_irq() not used for IRQ0 */
	.shutdown = NULL, /* shutdown_irq() not used for IRQ0 */
	.enable = enable_lapic_irq,
	.disable = disable_lapic_irq,
	.ack = ack_lapic_irq,
	.end = end_lapic_irq,
};

static void setup_nmi (void)
{
	/*
 	 * Dirty trick to enable the NMI watchdog ...
	 * We put the 8259A master into AEOI mode and
	 * unmask on all local APICs LVT0 as NMI.
	 *
	 * The idea to use the 8259A in AEOI mode ('8259A Virtual Wire')
	 * is from Maciej W. Rozycki - so we do not have to EOI from
	 * the NMI handler or the timer interrupt.
	 */ 
	printk(KERN_INFO "activating NMI Watchdog ...");

	enable_NMI_through_LVT0(NULL);

	printk(" done.\n");
}

/*
 * This looks a bit hackish but it's about the only one way of sending
 * a few INTA cycles to 8259As and any associated glue logic.  ICR does
 * not support the ExtINT mode, unfortunately.  We need to send these
 * cycles as some i82489DX-based boards have glue logic that keeps the
 * 8259A interrupt line asserted until INTA.  --macro
 */
static inline void unlock_ExtINT_logic(void)
{
	int apic, pin, i;
	struct IO_APIC_route_entry entry0, entry1;
	unsigned char save_control, save_freq_select;
	unsigned long flags;

	pin  = find_isa_irq_pin(8, mp_INT);
	apic = find_isa_irq_apic(8, mp_INT);
	if (pin == -1)
		return;

	spin_lock_irqsave(&ioapic_lock, flags);
	*(((int *)&entry0) + 1) = io_apic_read(apic, 0x11 + 2 * pin);
	*(((int *)&entry0) + 0) = io_apic_read(apic, 0x10 + 2 * pin);
	spin_unlock_irqrestore(&ioapic_lock, flags);
	clear_IO_APIC_pin(apic, pin);

	memset(&entry1, 0, sizeof(entry1));

	entry1.dest_mode = 0;			/* physical delivery */
	entry1.mask = 0;			/* unmask IRQ now */
	entry1.dest.physical.physical_dest = hard_smp_processor_id();
	entry1.delivery_mode = dest_ExtINT;
	entry1.polarity = entry0.polarity;
	entry1.trigger = 0;
	entry1.vector = 0;

	spin_lock_irqsave(&ioapic_lock, flags);
	io_apic_write(apic, 0x11 + 2 * pin, *(((int *)&entry1) + 1));
	io_apic_write(apic, 0x10 + 2 * pin, *(((int *)&entry1) + 0));
	spin_unlock_irqrestore(&ioapic_lock, flags);

	save_control = CMOS_READ(RTC_CONTROL);
	save_freq_select = CMOS_READ(RTC_FREQ_SELECT);
	CMOS_WRITE((save_freq_select & ~RTC_RATE_SELECT) | 0x6,
		   RTC_FREQ_SELECT);
	CMOS_WRITE(save_control | RTC_PIE, RTC_CONTROL);

	i = 100;
	while (i-- > 0) {
		mdelay(10);
		if ((CMOS_READ(RTC_INTR_FLAGS) & RTC_PF) == RTC_PF)
			i -= 10;
	}

	CMOS_WRITE(save_control, RTC_CONTROL);
	CMOS_WRITE(save_freq_select, RTC_FREQ_SELECT);
	clear_IO_APIC_pin(apic, pin);

	spin_lock_irqsave(&ioapic_lock, flags);
	io_apic_write(apic, 0x11 + 2 * pin, *(((int *)&entry0) + 1));
	io_apic_write(apic, 0x10 + 2 * pin, *(((int *)&entry0) + 0));
	spin_unlock_irqrestore(&ioapic_lock, flags);
}

int timer_uses_ioapic_pin_0;

/*
 * This code may look a bit paranoid, but it's supposed to cooperate with
 * a wide range of boards and BIOS bugs.  Fortunately only the timer IRQ
 * is so screwy.  Thanks to Brian Perkins for testing/hacking this beast
 * fanatically on his truly buggy board.
 *
 * FIXME: really need to revamp this for modern platforms only.
 */
static inline void check_timer(void)
{
	int apic1, pin1, apic2, pin2;
	int vector;

	/*
	 * get/set the timer IRQ vector:
	 */
	disable_8259A_irq(0);
	vector = assign_irq_vector(0);
	set_intr_gate(vector, interrupt[0]);

	/*
	 * Subtle, code in do_timer_interrupt() expects an AEOI
	 * mode for the 8259A whenever interrupts are routed
	 * through I/O APICs.  Also IRQ0 has to be enabled in
	 * the 8259A which implies the virtual wire has to be
	 * disabled in the local APIC.
	 */
	apic_write(APIC_LVT0, APIC_LVT_MASKED | APIC_DM_EXTINT);
	init_8259A(1);
	if (timer_over_8254 > 0)
		enable_8259A_irq(0);

	pin1  = find_isa_irq_pin(0, mp_INT);
	apic1 = find_isa_irq_apic(0, mp_INT);
	pin2  = ioapic_i8259.pin;
	apic2 = ioapic_i8259.apic;

	if (pin1 == 0)
		timer_uses_ioapic_pin_0 = 1;

	apic_printk(APIC_VERBOSE,KERN_INFO "..TIMER: vector=0x%02X apic1=%d pin1=%d apic2=%d pin2=%d\n",
		vector, apic1, pin1, apic2, pin2);

	if (pin1 != -1) {
		/*
		 * Ok, does IRQ0 through the IOAPIC work?
		 */
		unmask_IO_APIC_irq(0);
		if (!no_timer_check && timer_irq_works()) {
			nmi_watchdog_default();
			if (nmi_watchdog == NMI_IO_APIC) {
				disable_8259A_irq(0);
				setup_nmi();
				enable_8259A_irq(0);
			}
			if (disable_timer_pin_1 > 0)
				clear_IO_APIC_pin(0, pin1);
			return;
		}
		clear_IO_APIC_pin(apic1, pin1);
		apic_printk(APIC_QUIET,KERN_ERR "..MP-BIOS bug: 8254 timer not "
				"connected to IO-APIC\n");
	}

	apic_printk(APIC_VERBOSE,KERN_INFO "...trying to set up timer (IRQ0) "
				"through the 8259A ... ");
	if (pin2 != -1) {
		apic_printk(APIC_VERBOSE,"\n..... (found apic %d pin %d) ...",
			apic2, pin2);
		/*
		 * legacy devices should be connected to IO APIC #0
		 */
		setup_ExtINT_IRQ0_pin(apic2, pin2, vector);
		if (timer_irq_works()) {
			apic_printk(APIC_VERBOSE," works.\n");
			nmi_watchdog_default();
			if (nmi_watchdog == NMI_IO_APIC) {
				setup_nmi();
			}
			return;
		}
		/*
		 * Cleanup, just in case ...
		 */
		clear_IO_APIC_pin(apic2, pin2);
	}
	apic_printk(APIC_VERBOSE," failed.\n");

	if (nmi_watchdog == NMI_IO_APIC) {
		printk(KERN_WARNING "timer doesn't work through the IO-APIC - disabling NMI Watchdog!\n");
		nmi_watchdog = 0;
	}

	apic_printk(APIC_VERBOSE, KERN_INFO "...trying to set up timer as Virtual Wire IRQ...");

	disable_8259A_irq(0);
	irq_desc[0].chip = &lapic_irq_type;
	apic_write(APIC_LVT0, APIC_DM_FIXED | vector);	/* Fixed mode */
	enable_8259A_irq(0);

	if (timer_irq_works()) {
		apic_printk(APIC_VERBOSE," works.\n");
		return;
	}
	apic_write(APIC_LVT0, APIC_LVT_MASKED | APIC_DM_FIXED | vector);
	apic_printk(APIC_VERBOSE," failed.\n");

	apic_printk(APIC_VERBOSE, KERN_INFO "...trying to set up timer as ExtINT IRQ...");

	init_8259A(0);
	make_8259A_irq(0);
	apic_write(APIC_LVT0, APIC_DM_EXTINT);

	unlock_ExtINT_logic();

	if (timer_irq_works()) {
		apic_printk(APIC_VERBOSE," works.\n");
		return;
	}
	apic_printk(APIC_VERBOSE," failed :(.\n");
	panic("IO-APIC + timer doesn't work! Try using the 'noapic' kernel parameter\n");
}

static int __init notimercheck(char *s)
{
	no_timer_check = 1;
	return 1;
}
__setup("no_timer_check", notimercheck);

/*
 *
 * IRQ's that are handled by the PIC in the MPS IOAPIC case.
 * - IRQ2 is the cascade IRQ, and cannot be a io-apic IRQ.
 *   Linux doesn't really care, as it's not actually used
 *   for any interrupt handling anyway.
 */
#define PIC_IRQS	(1<<2)

void __init setup_IO_APIC(void)
{
	enable_IO_APIC();

	if (acpi_ioapic)
		io_apic_irqs = ~0;	/* all IRQs go through IOAPIC */
	else
		io_apic_irqs = ~PIC_IRQS;

	apic_printk(APIC_VERBOSE, "ENABLING IO-APIC IRQs\n");

	sync_Arb_IDs();
	setup_IO_APIC_irqs();
	init_IO_APIC_traps();
	check_timer();
	if (!acpi_ioapic)
		print_IO_APIC();
}

struct sysfs_ioapic_data {
	struct sys_device dev;
	struct IO_APIC_route_entry entry[0];
};
static struct sysfs_ioapic_data * mp_ioapic_data[MAX_IO_APICS];

static int ioapic_suspend(struct sys_device *dev, pm_message_t state)
{
	struct IO_APIC_route_entry *entry;
	struct sysfs_ioapic_data *data;
	int i;

	data = container_of(dev, struct sysfs_ioapic_data, dev);
	entry = data->entry;
	for (i = 0; i < nr_ioapic_registers[dev->id]; i ++, entry ++ )
		*entry = ioapic_read_entry(dev->id, i);

	return 0;
}

static int ioapic_resume(struct sys_device *dev)
{
	struct IO_APIC_route_entry *entry;
	struct sysfs_ioapic_data *data;
	unsigned long flags;
	union IO_APIC_reg_00 reg_00;
	int i;

	data = container_of(dev, struct sysfs_ioapic_data, dev);
	entry = data->entry;

	spin_lock_irqsave(&ioapic_lock, flags);
	reg_00.raw = io_apic_read(dev->id, 0);
	if (reg_00.bits.ID != mp_ioapics[dev->id].mpc_apicid) {
		reg_00.bits.ID = mp_ioapics[dev->id].mpc_apicid;
		io_apic_write(dev->id, 0, reg_00.raw);
	}
	spin_unlock_irqrestore(&ioapic_lock, flags);
	for (i = 0; i < nr_ioapic_registers[dev->id]; i++)
		ioapic_write_entry(dev->id, i, entry[i]);

	return 0;
}

static struct sysdev_class ioapic_sysdev_class = {
	set_kset_name("ioapic"),
	.suspend = ioapic_suspend,
	.resume = ioapic_resume,
};

static int __init ioapic_init_sysfs(void)
{
	struct sys_device * dev;
	int i, size, error = 0;

	error = sysdev_class_register(&ioapic_sysdev_class);
	if (error)
		return error;

	for (i = 0; i < nr_ioapics; i++ ) {
		size = sizeof(struct sys_device) + nr_ioapic_registers[i]
			* sizeof(struct IO_APIC_route_entry);
		mp_ioapic_data[i] = kmalloc(size, GFP_KERNEL);
		if (!mp_ioapic_data[i]) {
			printk(KERN_ERR "Can't suspend/resume IOAPIC %d\n", i);
			continue;
		}
		memset(mp_ioapic_data[i], 0, size);
		dev = &mp_ioapic_data[i]->dev;
		dev->id = i;
		dev->cls = &ioapic_sysdev_class;
		error = sysdev_register(dev);
		if (error) {
			kfree(mp_ioapic_data[i]);
			mp_ioapic_data[i] = NULL;
			printk(KERN_ERR "Can't suspend/resume IOAPIC %d\n", i);
			continue;
		}
	}

	return 0;
}

device_initcall(ioapic_init_sysfs);

/* --------------------------------------------------------------------------
                          ACPI-based IOAPIC Configuration
   -------------------------------------------------------------------------- */

#ifdef CONFIG_ACPI

#define IO_APIC_MAX_ID		0xFE

int __init io_apic_get_redir_entries (int ioapic)
{
	union IO_APIC_reg_01	reg_01;
	unsigned long flags;

	spin_lock_irqsave(&ioapic_lock, flags);
	reg_01.raw = io_apic_read(ioapic, 1);
	spin_unlock_irqrestore(&ioapic_lock, flags);

	return reg_01.bits.entries;
}


int io_apic_set_pci_routing (int ioapic, int pin, int irq, int triggering, int polarity)
{
	struct IO_APIC_route_entry entry;
	unsigned long flags;

	if (!IO_APIC_IRQ(irq)) {
		apic_printk(APIC_QUIET,KERN_ERR "IOAPIC[%d]: Invalid reference to IRQ 0\n",
			ioapic);
		return -EINVAL;
	}

	/*
	 * Generate a PCI IRQ routing entry and program the IOAPIC accordingly.
	 * Note that we mask (disable) IRQs now -- these get enabled when the
	 * corresponding device driver registers for this IRQ.
	 */

	memset(&entry,0,sizeof(entry));

	entry.delivery_mode = INT_DELIVERY_MODE;
	entry.dest_mode = INT_DEST_MODE;
	entry.dest.logical.logical_dest = cpu_mask_to_apicid(TARGET_CPUS);
	entry.trigger = triggering;
	entry.polarity = polarity;
	entry.mask = 1;					 /* Disabled (masked) */

	irq = gsi_irq_sharing(irq);
	/*
	 * IRQs < 16 are already in the irq_2_pin[] map
	 */
	if (irq >= 16)
		add_pin_to_irq(irq, ioapic, pin);

	entry.vector = assign_irq_vector(irq);

	apic_printk(APIC_VERBOSE,KERN_DEBUG "IOAPIC[%d]: Set PCI routing entry (%d-%d -> 0x%x -> "
		"IRQ %d Mode:%i Active:%i)\n", ioapic, 
	       mp_ioapics[ioapic].mpc_apicid, pin, entry.vector, irq,
	       triggering, polarity);

	ioapic_register_intr(irq, entry.vector, triggering);

	if (!ioapic && (irq < 16))
		disable_8259A_irq(irq);

	ioapic_write_entry(ioapic, pin, entry);

	spin_lock_irqsave(&ioapic_lock, flags);
	set_native_irq_info(use_pci_vector() ? entry.vector : irq, TARGET_CPUS);
	spin_unlock_irqrestore(&ioapic_lock, flags);

	return 0;
}

#endif /* CONFIG_ACPI */


/*
 * This function currently is only a helper for the i386 smp boot process where
 * we need to reprogram the ioredtbls to cater for the cpus which have come online
 * so mask in all cases should simply be TARGET_CPUS
 */
#ifdef CONFIG_SMP
void __init setup_ioapic_dest(void)
{
	int pin, ioapic, irq, irq_entry;

	if (skip_ioapic_setup == 1)
		return;

	for (ioapic = 0; ioapic < nr_ioapics; ioapic++) {
		for (pin = 0; pin < nr_ioapic_registers[ioapic]; pin++) {
			irq_entry = find_irq_entry(ioapic, pin, mp_INT);
			if (irq_entry == -1)
				continue;
			irq = pin_2_irq(irq_entry, ioapic, pin);
			set_ioapic_affinity_irq(irq, TARGET_CPUS);
		}

	}
}
#endif
OpenPOWER on IntegriCloud