summaryrefslogtreecommitdiffstats
path: root/drivers/rapidio/rio.c
blob: b17d5218005e154ac287df6c9eade6568ba280d8 (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
/*
 * RapidIO interconnect services
 * (RapidIO Interconnect Specification, http://www.rapidio.org)
 *
 * Copyright 2005 MontaVista Software, Inc.
 * Matt Porter <mporter@kernel.crashing.org>
 *
 * Copyright 2009 Integrated Device Technology, Inc.
 * Alex Bounine <alexandre.bounine@idt.com>
 *
 * This program is free software; you can redistribute  it and/or modify it
 * under  the terms of  the GNU General  Public License as published by the
 * Free Software Foundation;  either version 2 of the  License, or (at your
 * option) any later version.
 */

#include <linux/types.h>
#include <linux/kernel.h>

#include <linux/delay.h>
#include <linux/init.h>
#include <linux/rio.h>
#include <linux/rio_drv.h>
#include <linux/rio_ids.h>
#include <linux/rio_regs.h>
#include <linux/module.h>
#include <linux/spinlock.h>
#include <linux/slab.h>
#include <linux/interrupt.h>

#include "rio.h"

static LIST_HEAD(rio_devices);
static DEFINE_SPINLOCK(rio_global_list_lock);

static LIST_HEAD(rio_mports);
static DEFINE_MUTEX(rio_mport_list_lock);
static unsigned char next_portid;
static DEFINE_SPINLOCK(rio_mmap_lock);

/**
 * rio_local_get_device_id - Get the base/extended device id for a port
 * @port: RIO master port from which to get the deviceid
 *
 * Reads the base/extended device id from the local device
 * implementing the master port. Returns the 8/16-bit device
 * id.
 */
u16 rio_local_get_device_id(struct rio_mport *port)
{
	u32 result;

	rio_local_read_config_32(port, RIO_DID_CSR, &result);

	return (RIO_GET_DID(port->sys_size, result));
}

/**
 * rio_add_device- Adds a RIO device to the device model
 * @rdev: RIO device
 *
 * Adds the RIO device to the global device list and adds the RIO
 * device to the RIO device list.  Creates the generic sysfs nodes
 * for an RIO device.
 */
int rio_add_device(struct rio_dev *rdev)
{
	int err;

	err = device_add(&rdev->dev);
	if (err)
		return err;

	spin_lock(&rio_global_list_lock);
	list_add_tail(&rdev->global_list, &rio_devices);
	spin_unlock(&rio_global_list_lock);

	rio_create_sysfs_dev_files(rdev);

	return 0;
}
EXPORT_SYMBOL_GPL(rio_add_device);

/**
 * rio_request_inb_mbox - request inbound mailbox service
 * @mport: RIO master port from which to allocate the mailbox resource
 * @dev_id: Device specific pointer to pass on event
 * @mbox: Mailbox number to claim
 * @entries: Number of entries in inbound mailbox queue
 * @minb: Callback to execute when inbound message is received
 *
 * Requests ownership of an inbound mailbox resource and binds
 * a callback function to the resource. Returns %0 on success.
 */
int rio_request_inb_mbox(struct rio_mport *mport,
			 void *dev_id,
			 int mbox,
			 int entries,
			 void (*minb) (struct rio_mport * mport, void *dev_id, int mbox,
				       int slot))
{
	int rc = -ENOSYS;
	struct resource *res;

	if (mport->ops->open_inb_mbox == NULL)
		goto out;

	res = kmalloc(sizeof(struct resource), GFP_KERNEL);

	if (res) {
		rio_init_mbox_res(res, mbox, mbox);

		/* Make sure this mailbox isn't in use */
		if ((rc =
		     request_resource(&mport->riores[RIO_INB_MBOX_RESOURCE],
				      res)) < 0) {
			kfree(res);
			goto out;
		}

		mport->inb_msg[mbox].res = res;

		/* Hook the inbound message callback */
		mport->inb_msg[mbox].mcback = minb;

		rc = mport->ops->open_inb_mbox(mport, dev_id, mbox, entries);
	} else
		rc = -ENOMEM;

      out:
	return rc;
}

/**
 * rio_release_inb_mbox - release inbound mailbox message service
 * @mport: RIO master port from which to release the mailbox resource
 * @mbox: Mailbox number to release
 *
 * Releases ownership of an inbound mailbox resource. Returns 0
 * if the request has been satisfied.
 */
int rio_release_inb_mbox(struct rio_mport *mport, int mbox)
{
	if (mport->ops->close_inb_mbox) {
		mport->ops->close_inb_mbox(mport, mbox);

		/* Release the mailbox resource */
		return release_resource(mport->inb_msg[mbox].res);
	} else
		return -ENOSYS;
}

/**
 * rio_request_outb_mbox - request outbound mailbox service
 * @mport: RIO master port from which to allocate the mailbox resource
 * @dev_id: Device specific pointer to pass on event
 * @mbox: Mailbox number to claim
 * @entries: Number of entries in outbound mailbox queue
 * @moutb: Callback to execute when outbound message is sent
 *
 * Requests ownership of an outbound mailbox resource and binds
 * a callback function to the resource. Returns 0 on success.
 */
int rio_request_outb_mbox(struct rio_mport *mport,
			  void *dev_id,
			  int mbox,
			  int entries,
			  void (*moutb) (struct rio_mport * mport, void *dev_id, int mbox, int slot))
{
	int rc = -ENOSYS;
	struct resource *res;

	if (mport->ops->open_outb_mbox == NULL)
		goto out;

	res = kmalloc(sizeof(struct resource), GFP_KERNEL);

	if (res) {
		rio_init_mbox_res(res, mbox, mbox);

		/* Make sure this outbound mailbox isn't in use */
		if ((rc =
		     request_resource(&mport->riores[RIO_OUTB_MBOX_RESOURCE],
				      res)) < 0) {
			kfree(res);
			goto out;
		}

		mport->outb_msg[mbox].res = res;

		/* Hook the inbound message callback */
		mport->outb_msg[mbox].mcback = moutb;

		rc = mport->ops->open_outb_mbox(mport, dev_id, mbox, entries);
	} else
		rc = -ENOMEM;

      out:
	return rc;
}

/**
 * rio_release_outb_mbox - release outbound mailbox message service
 * @mport: RIO master port from which to release the mailbox resource
 * @mbox: Mailbox number to release
 *
 * Releases ownership of an inbound mailbox resource. Returns 0
 * if the request has been satisfied.
 */
int rio_release_outb_mbox(struct rio_mport *mport, int mbox)
{
	if (mport->ops->close_outb_mbox) {
		mport->ops->close_outb_mbox(mport, mbox);

		/* Release the mailbox resource */
		return release_resource(mport->outb_msg[mbox].res);
	} else
		return -ENOSYS;
}

/**
 * rio_setup_inb_dbell - bind inbound doorbell callback
 * @mport: RIO master port to bind the doorbell callback
 * @dev_id: Device specific pointer to pass on event
 * @res: Doorbell message resource
 * @dinb: Callback to execute when doorbell is received
 *
 * Adds a doorbell resource/callback pair into a port's
 * doorbell event list. Returns 0 if the request has been
 * satisfied.
 */
static int
rio_setup_inb_dbell(struct rio_mport *mport, void *dev_id, struct resource *res,
		    void (*dinb) (struct rio_mport * mport, void *dev_id, u16 src, u16 dst,
				  u16 info))
{
	int rc = 0;
	struct rio_dbell *dbell;

	if (!(dbell = kmalloc(sizeof(struct rio_dbell), GFP_KERNEL))) {
		rc = -ENOMEM;
		goto out;
	}

	dbell->res = res;
	dbell->dinb = dinb;
	dbell->dev_id = dev_id;

	list_add_tail(&dbell->node, &mport->dbells);

      out:
	return rc;
}

/**
 * rio_request_inb_dbell - request inbound doorbell message service
 * @mport: RIO master port from which to allocate the doorbell resource
 * @dev_id: Device specific pointer to pass on event
 * @start: Doorbell info range start
 * @end: Doorbell info range end
 * @dinb: Callback to execute when doorbell is received
 *
 * Requests ownership of an inbound doorbell resource and binds
 * a callback function to the resource. Returns 0 if the request
 * has been satisfied.
 */
int rio_request_inb_dbell(struct rio_mport *mport,
			  void *dev_id,
			  u16 start,
			  u16 end,
			  void (*dinb) (struct rio_mport * mport, void *dev_id, u16 src,
					u16 dst, u16 info))
{
	int rc = 0;

	struct resource *res = kmalloc(sizeof(struct resource), GFP_KERNEL);

	if (res) {
		rio_init_dbell_res(res, start, end);

		/* Make sure these doorbells aren't in use */
		if ((rc =
		     request_resource(&mport->riores[RIO_DOORBELL_RESOURCE],
				      res)) < 0) {
			kfree(res);
			goto out;
		}

		/* Hook the doorbell callback */
		rc = rio_setup_inb_dbell(mport, dev_id, res, dinb);
	} else
		rc = -ENOMEM;

      out:
	return rc;
}

/**
 * rio_release_inb_dbell - release inbound doorbell message service
 * @mport: RIO master port from which to release the doorbell resource
 * @start: Doorbell info range start
 * @end: Doorbell info range end
 *
 * Releases ownership of an inbound doorbell resource and removes
 * callback from the doorbell event list. Returns 0 if the request
 * has been satisfied.
 */
int rio_release_inb_dbell(struct rio_mport *mport, u16 start, u16 end)
{
	int rc = 0, found = 0;
	struct rio_dbell *dbell;

	list_for_each_entry(dbell, &mport->dbells, node) {
		if ((dbell->res->start == start) && (dbell->res->end == end)) {
			found = 1;
			break;
		}
	}

	/* If we can't find an exact match, fail */
	if (!found) {
		rc = -EINVAL;
		goto out;
	}

	/* Delete from list */
	list_del(&dbell->node);

	/* Release the doorbell resource */
	rc = release_resource(dbell->res);

	/* Free the doorbell event */
	kfree(dbell);

      out:
	return rc;
}

/**
 * rio_request_outb_dbell - request outbound doorbell message range
 * @rdev: RIO device from which to allocate the doorbell resource
 * @start: Doorbell message range start
 * @end: Doorbell message range end
 *
 * Requests ownership of a doorbell message range. Returns a resource
 * if the request has been satisfied or %NULL on failure.
 */
struct resource *rio_request_outb_dbell(struct rio_dev *rdev, u16 start,
					u16 end)
{
	struct resource *res = kmalloc(sizeof(struct resource), GFP_KERNEL);

	if (res) {
		rio_init_dbell_res(res, start, end);

		/* Make sure these doorbells aren't in use */
		if (request_resource(&rdev->riores[RIO_DOORBELL_RESOURCE], res)
		    < 0) {
			kfree(res);
			res = NULL;
		}
	}

	return res;
}

/**
 * rio_release_outb_dbell - release outbound doorbell message range
 * @rdev: RIO device from which to release the doorbell resource
 * @res: Doorbell resource to be freed
 *
 * Releases ownership of a doorbell message range. Returns 0 if the
 * request has been satisfied.
 */
int rio_release_outb_dbell(struct rio_dev *rdev, struct resource *res)
{
	int rc = release_resource(res);

	kfree(res);

	return rc;
}

/**
 * rio_request_inb_pwrite - request inbound port-write message service
 * @rdev: RIO device to which register inbound port-write callback routine
 * @pwcback: Callback routine to execute when port-write is received
 *
 * Binds a port-write callback function to the RapidIO device.
 * Returns 0 if the request has been satisfied.
 */
int rio_request_inb_pwrite(struct rio_dev *rdev,
	int (*pwcback)(struct rio_dev *rdev, union rio_pw_msg *msg, int step))
{
	int rc = 0;

	spin_lock(&rio_global_list_lock);
	if (rdev->pwcback != NULL)
		rc = -ENOMEM;
	else
		rdev->pwcback = pwcback;

	spin_unlock(&rio_global_list_lock);
	return rc;
}
EXPORT_SYMBOL_GPL(rio_request_inb_pwrite);

/**
 * rio_release_inb_pwrite - release inbound port-write message service
 * @rdev: RIO device which registered for inbound port-write callback
 *
 * Removes callback from the rio_dev structure. Returns 0 if the request
 * has been satisfied.
 */
int rio_release_inb_pwrite(struct rio_dev *rdev)
{
	int rc = -ENOMEM;

	spin_lock(&rio_global_list_lock);
	if (rdev->pwcback) {
		rdev->pwcback = NULL;
		rc = 0;
	}

	spin_unlock(&rio_global_list_lock);
	return rc;
}
EXPORT_SYMBOL_GPL(rio_release_inb_pwrite);

/**
 * rio_map_inb_region -- Map inbound memory region.
 * @mport: Master port.
 * @local: physical address of memory region to be mapped
 * @rbase: RIO base address assigned to this window
 * @size: Size of the memory region
 * @rflags: Flags for mapping.
 *
 * Return: 0 -- Success.
 *
 * This function will create the mapping from RIO space to local memory.
 */
int rio_map_inb_region(struct rio_mport *mport, dma_addr_t local,
			u64 rbase, u32 size, u32 rflags)
{
	int rc = 0;
	unsigned long flags;

	if (!mport->ops->map_inb)
		return -1;
	spin_lock_irqsave(&rio_mmap_lock, flags);
	rc = mport->ops->map_inb(mport, local, rbase, size, rflags);
	spin_unlock_irqrestore(&rio_mmap_lock, flags);
	return rc;
}
EXPORT_SYMBOL_GPL(rio_map_inb_region);

/**
 * rio_unmap_inb_region -- Unmap the inbound memory region
 * @mport: Master port
 * @lstart: physical address of memory region to be unmapped
 */
void rio_unmap_inb_region(struct rio_mport *mport, dma_addr_t lstart)
{
	unsigned long flags;
	if (!mport->ops->unmap_inb)
		return;
	spin_lock_irqsave(&rio_mmap_lock, flags);
	mport->ops->unmap_inb(mport, lstart);
	spin_unlock_irqrestore(&rio_mmap_lock, flags);
}
EXPORT_SYMBOL_GPL(rio_unmap_inb_region);

/**
 * rio_mport_get_physefb - Helper function that returns register offset
 *                      for Physical Layer Extended Features Block.
 * @port: Master port to issue transaction
 * @local: Indicate a local master port or remote device access
 * @destid: Destination ID of the device
 * @hopcount: Number of switch hops to the device
 */
u32
rio_mport_get_physefb(struct rio_mport *port, int local,
		      u16 destid, u8 hopcount)
{
	u32 ext_ftr_ptr;
	u32 ftr_header;

	ext_ftr_ptr = rio_mport_get_efb(port, local, destid, hopcount, 0);

	while (ext_ftr_ptr)  {
		if (local)
			rio_local_read_config_32(port, ext_ftr_ptr,
						 &ftr_header);
		else
			rio_mport_read_config_32(port, destid, hopcount,
						 ext_ftr_ptr, &ftr_header);

		ftr_header = RIO_GET_BLOCK_ID(ftr_header);
		switch (ftr_header) {

		case RIO_EFB_SER_EP_ID_V13P:
		case RIO_EFB_SER_EP_REC_ID_V13P:
		case RIO_EFB_SER_EP_FREE_ID_V13P:
		case RIO_EFB_SER_EP_ID:
		case RIO_EFB_SER_EP_REC_ID:
		case RIO_EFB_SER_EP_FREE_ID:
		case RIO_EFB_SER_EP_FREC_ID:

			return ext_ftr_ptr;

		default:
			break;
		}

		ext_ftr_ptr = rio_mport_get_efb(port, local, destid,
						hopcount, ext_ftr_ptr);
	}

	return ext_ftr_ptr;
}
EXPORT_SYMBOL_GPL(rio_mport_get_physefb);

/**
 * rio_get_comptag - Begin or continue searching for a RIO device by component tag
 * @comp_tag: RIO component tag to match
 * @from: Previous RIO device found in search, or %NULL for new search
 *
 * Iterates through the list of known RIO devices. If a RIO device is
 * found with a matching @comp_tag, a pointer to its device
 * structure is returned. Otherwise, %NULL is returned. A new search
 * is initiated by passing %NULL to the @from argument. Otherwise, if
 * @from is not %NULL, searches continue from next device on the global
 * list.
 */
struct rio_dev *rio_get_comptag(u32 comp_tag, struct rio_dev *from)
{
	struct list_head *n;
	struct rio_dev *rdev;

	spin_lock(&rio_global_list_lock);
	n = from ? from->global_list.next : rio_devices.next;

	while (n && (n != &rio_devices)) {
		rdev = rio_dev_g(n);
		if (rdev->comp_tag == comp_tag)
			goto exit;
		n = n->next;
	}
	rdev = NULL;
exit:
	spin_unlock(&rio_global_list_lock);
	return rdev;
}
EXPORT_SYMBOL_GPL(rio_get_comptag);

/**
 * rio_set_port_lockout - Sets/clears LOCKOUT bit (RIO EM 1.3) for a switch port.
 * @rdev: Pointer to RIO device control structure
 * @pnum: Switch port number to set LOCKOUT bit
 * @lock: Operation : set (=1) or clear (=0)
 */
int rio_set_port_lockout(struct rio_dev *rdev, u32 pnum, int lock)
{
	u32 regval;

	rio_read_config_32(rdev,
				 rdev->phys_efptr + RIO_PORT_N_CTL_CSR(pnum),
				 &regval);
	if (lock)
		regval |= RIO_PORT_N_CTL_LOCKOUT;
	else
		regval &= ~RIO_PORT_N_CTL_LOCKOUT;

	rio_write_config_32(rdev,
				  rdev->phys_efptr + RIO_PORT_N_CTL_CSR(pnum),
				  regval);
	return 0;
}
EXPORT_SYMBOL_GPL(rio_set_port_lockout);

/**
 * rio_enable_rx_tx_port - enable input receiver and output transmitter of
 * given port
 * @port: Master port associated with the RIO network
 * @local: local=1 select local port otherwise a far device is reached
 * @destid: Destination ID of the device to check host bit
 * @hopcount: Number of hops to reach the target
 * @port_num: Port (-number on switch) to enable on a far end device
 *
 * Returns 0 or 1 from on General Control Command and Status Register
 * (EXT_PTR+0x3C)
 */
int rio_enable_rx_tx_port(struct rio_mport *port,
			  int local, u16 destid,
			  u8 hopcount, u8 port_num)
{
#ifdef CONFIG_RAPIDIO_ENABLE_RX_TX_PORTS
	u32 regval;
	u32 ext_ftr_ptr;

	/*
	* enable rx input tx output port
	*/
	pr_debug("rio_enable_rx_tx_port(local = %d, destid = %d, hopcount = "
		 "%d, port_num = %d)\n", local, destid, hopcount, port_num);

	ext_ftr_ptr = rio_mport_get_physefb(port, local, destid, hopcount);

	if (local) {
		rio_local_read_config_32(port, ext_ftr_ptr +
				RIO_PORT_N_CTL_CSR(0),
				&regval);
	} else {
		if (rio_mport_read_config_32(port, destid, hopcount,
		ext_ftr_ptr + RIO_PORT_N_CTL_CSR(port_num), &regval) < 0)
			return -EIO;
	}

	if (regval & RIO_PORT_N_CTL_P_TYP_SER) {
		/* serial */
		regval = regval | RIO_PORT_N_CTL_EN_RX_SER
				| RIO_PORT_N_CTL_EN_TX_SER;
	} else {
		/* parallel */
		regval = regval | RIO_PORT_N_CTL_EN_RX_PAR
				| RIO_PORT_N_CTL_EN_TX_PAR;
	}

	if (local) {
		rio_local_write_config_32(port, ext_ftr_ptr +
					  RIO_PORT_N_CTL_CSR(0), regval);
	} else {
		if (rio_mport_write_config_32(port, destid, hopcount,
		    ext_ftr_ptr + RIO_PORT_N_CTL_CSR(port_num), regval) < 0)
			return -EIO;
	}
#endif
	return 0;
}
EXPORT_SYMBOL_GPL(rio_enable_rx_tx_port);


/**
 * rio_chk_dev_route - Validate route to the specified device.
 * @rdev:  RIO device failed to respond
 * @nrdev: Last active device on the route to rdev
 * @npnum: nrdev's port number on the route to rdev
 *
 * Follows a route to the specified RIO device to determine the last available
 * device (and corresponding RIO port) on the route.
 */
static int
rio_chk_dev_route(struct rio_dev *rdev, struct rio_dev **nrdev, int *npnum)
{
	u32 result;
	int p_port, rc = -EIO;
	struct rio_dev *prev = NULL;

	/* Find switch with failed RIO link */
	while (rdev->prev && (rdev->prev->pef & RIO_PEF_SWITCH)) {
		if (!rio_read_config_32(rdev->prev, RIO_DEV_ID_CAR, &result)) {
			prev = rdev->prev;
			break;
		}
		rdev = rdev->prev;
	}

	if (prev == NULL)
		goto err_out;

	p_port = prev->rswitch->route_table[rdev->destid];

	if (p_port != RIO_INVALID_ROUTE) {
		pr_debug("RIO: link failed on [%s]-P%d\n",
			 rio_name(prev), p_port);
		*nrdev = prev;
		*npnum = p_port;
		rc = 0;
	} else
		pr_debug("RIO: failed to trace route to %s\n", rio_name(rdev));
err_out:
	return rc;
}

/**
 * rio_mport_chk_dev_access - Validate access to the specified device.
 * @mport: Master port to send transactions
 * @destid: Device destination ID in network
 * @hopcount: Number of hops into the network
 */
int
rio_mport_chk_dev_access(struct rio_mport *mport, u16 destid, u8 hopcount)
{
	int i = 0;
	u32 tmp;

	while (rio_mport_read_config_32(mport, destid, hopcount,
					RIO_DEV_ID_CAR, &tmp)) {
		i++;
		if (i == RIO_MAX_CHK_RETRY)
			return -EIO;
		mdelay(1);
	}

	return 0;
}
EXPORT_SYMBOL_GPL(rio_mport_chk_dev_access);

/**
 * rio_chk_dev_access - Validate access to the specified device.
 * @rdev: Pointer to RIO device control structure
 */
static int rio_chk_dev_access(struct rio_dev *rdev)
{
	return rio_mport_chk_dev_access(rdev->net->hport,
					rdev->destid, rdev->hopcount);
}

/**
 * rio_get_input_status - Sends a Link-Request/Input-Status control symbol and
 *                        returns link-response (if requested).
 * @rdev: RIO devive to issue Input-status command
 * @pnum: Device port number to issue the command
 * @lnkresp: Response from a link partner
 */
static int
rio_get_input_status(struct rio_dev *rdev, int pnum, u32 *lnkresp)
{
	u32 regval;
	int checkcount;

	if (lnkresp) {
		/* Read from link maintenance response register
		 * to clear valid bit */
		rio_read_config_32(rdev,
			rdev->phys_efptr + RIO_PORT_N_MNT_RSP_CSR(pnum),
			&regval);
		udelay(50);
	}

	/* Issue Input-status command */
	rio_write_config_32(rdev,
		rdev->phys_efptr + RIO_PORT_N_MNT_REQ_CSR(pnum),
		RIO_MNT_REQ_CMD_IS);

	/* Exit if the response is not expected */
	if (lnkresp == NULL)
		return 0;

	checkcount = 3;
	while (checkcount--) {
		udelay(50);
		rio_read_config_32(rdev,
			rdev->phys_efptr + RIO_PORT_N_MNT_RSP_CSR(pnum),
			&regval);
		if (regval & RIO_PORT_N_MNT_RSP_RVAL) {
			*lnkresp = regval;
			return 0;
		}
	}

	return -EIO;
}

/**
 * rio_clr_err_stopped - Clears port Error-stopped states.
 * @rdev: Pointer to RIO device control structure
 * @pnum: Switch port number to clear errors
 * @err_status: port error status (if 0 reads register from device)
 */
static int rio_clr_err_stopped(struct rio_dev *rdev, u32 pnum, u32 err_status)
{
	struct rio_dev *nextdev = rdev->rswitch->nextdev[pnum];
	u32 regval;
	u32 far_ackid, far_linkstat, near_ackid;

	if (err_status == 0)
		rio_read_config_32(rdev,
			rdev->phys_efptr + RIO_PORT_N_ERR_STS_CSR(pnum),
			&err_status);

	if (err_status & RIO_PORT_N_ERR_STS_PW_OUT_ES) {
		pr_debug("RIO_EM: servicing Output Error-Stopped state\n");
		/*
		 * Send a Link-Request/Input-Status control symbol
		 */
		if (rio_get_input_status(rdev, pnum, &regval)) {
			pr_debug("RIO_EM: Input-status response timeout\n");
			goto rd_err;
		}

		pr_debug("RIO_EM: SP%d Input-status response=0x%08x\n",
			 pnum, regval);
		far_ackid = (regval & RIO_PORT_N_MNT_RSP_ASTAT) >> 5;
		far_linkstat = regval & RIO_PORT_N_MNT_RSP_LSTAT;
		rio_read_config_32(rdev,
			rdev->phys_efptr + RIO_PORT_N_ACK_STS_CSR(pnum),
			&regval);
		pr_debug("RIO_EM: SP%d_ACK_STS_CSR=0x%08x\n", pnum, regval);
		near_ackid = (regval & RIO_PORT_N_ACK_INBOUND) >> 24;
		pr_debug("RIO_EM: SP%d far_ackID=0x%02x far_linkstat=0x%02x" \
			 " near_ackID=0x%02x\n",
			pnum, far_ackid, far_linkstat, near_ackid);

		/*
		 * If required, synchronize ackIDs of near and
		 * far sides.
		 */
		if ((far_ackid != ((regval & RIO_PORT_N_ACK_OUTSTAND) >> 8)) ||
		    (far_ackid != (regval & RIO_PORT_N_ACK_OUTBOUND))) {
			/* Align near outstanding/outbound ackIDs with
			 * far inbound.
			 */
			rio_write_config_32(rdev,
				rdev->phys_efptr + RIO_PORT_N_ACK_STS_CSR(pnum),
				(near_ackid << 24) |
					(far_ackid << 8) | far_ackid);
			/* Align far outstanding/outbound ackIDs with
			 * near inbound.
			 */
			far_ackid++;
			if (nextdev)
				rio_write_config_32(nextdev,
					nextdev->phys_efptr +
					RIO_PORT_N_ACK_STS_CSR(RIO_GET_PORT_NUM(nextdev->swpinfo)),
					(far_ackid << 24) |
					(near_ackid << 8) | near_ackid);
			else
				pr_debug("RIO_EM: Invalid nextdev pointer (NULL)\n");
		}
rd_err:
		rio_read_config_32(rdev,
			rdev->phys_efptr + RIO_PORT_N_ERR_STS_CSR(pnum),
			&err_status);
		pr_debug("RIO_EM: SP%d_ERR_STS_CSR=0x%08x\n", pnum, err_status);
	}

	if ((err_status & RIO_PORT_N_ERR_STS_PW_INP_ES) && nextdev) {
		pr_debug("RIO_EM: servicing Input Error-Stopped state\n");
		rio_get_input_status(nextdev,
				     RIO_GET_PORT_NUM(nextdev->swpinfo), NULL);
		udelay(50);

		rio_read_config_32(rdev,
			rdev->phys_efptr + RIO_PORT_N_ERR_STS_CSR(pnum),
			&err_status);
		pr_debug("RIO_EM: SP%d_ERR_STS_CSR=0x%08x\n", pnum, err_status);
	}

	return (err_status & (RIO_PORT_N_ERR_STS_PW_OUT_ES |
			      RIO_PORT_N_ERR_STS_PW_INP_ES)) ? 1 : 0;
}

/**
 * rio_inb_pwrite_handler - process inbound port-write message
 * @pw_msg: pointer to inbound port-write message
 *
 * Processes an inbound port-write message. Returns 0 if the request
 * has been satisfied.
 */
int rio_inb_pwrite_handler(union rio_pw_msg *pw_msg)
{
	struct rio_dev *rdev;
	u32 err_status, em_perrdet, em_ltlerrdet;
	int rc, portnum;

	rdev = rio_get_comptag((pw_msg->em.comptag & RIO_CTAG_UDEVID), NULL);
	if (rdev == NULL) {
		/* Device removed or enumeration error */
		pr_debug("RIO: %s No matching device for CTag 0x%08x\n",
			__func__, pw_msg->em.comptag);
		return -EIO;
	}

	pr_debug("RIO: Port-Write message from %s\n", rio_name(rdev));

#ifdef DEBUG_PW
	{
	u32 i;
	for (i = 0; i < RIO_PW_MSG_SIZE/sizeof(u32);) {
			pr_debug("0x%02x: %08x %08x %08x %08x\n",
				 i*4, pw_msg->raw[i], pw_msg->raw[i + 1],
				 pw_msg->raw[i + 2], pw_msg->raw[i + 3]);
			i += 4;
	}
	}
#endif

	/* Call an external service function (if such is registered
	 * for this device). This may be the service for endpoints that send
	 * device-specific port-write messages. End-point messages expected
	 * to be handled completely by EP specific device driver.
	 * For switches rc==0 signals that no standard processing required.
	 */
	if (rdev->pwcback != NULL) {
		rc = rdev->pwcback(rdev, pw_msg, 0);
		if (rc == 0)
			return 0;
	}

	portnum = pw_msg->em.is_port & 0xFF;

	/* Check if device and route to it are functional:
	 * Sometimes devices may send PW message(s) just before being
	 * powered down (or link being lost).
	 */
	if (rio_chk_dev_access(rdev)) {
		pr_debug("RIO: device access failed - get link partner\n");
		/* Scan route to the device and identify failed link.
		 * This will replace device and port reported in PW message.
		 * PW message should not be used after this point.
		 */
		if (rio_chk_dev_route(rdev, &rdev, &portnum)) {
			pr_err("RIO: Route trace for %s failed\n",
				rio_name(rdev));
			return -EIO;
		}
		pw_msg = NULL;
	}

	/* For End-point devices processing stops here */
	if (!(rdev->pef & RIO_PEF_SWITCH))
		return 0;

	if (rdev->phys_efptr == 0) {
		pr_err("RIO_PW: Bad switch initialization for %s\n",
			rio_name(rdev));
		return 0;
	}

	/*
	 * Process the port-write notification from switch
	 */
	if (rdev->rswitch->ops && rdev->rswitch->ops->em_handle)
		rdev->rswitch->ops->em_handle(rdev, portnum);

	rio_read_config_32(rdev,
			rdev->phys_efptr + RIO_PORT_N_ERR_STS_CSR(portnum),
			&err_status);
	pr_debug("RIO_PW: SP%d_ERR_STS_CSR=0x%08x\n", portnum, err_status);

	if (err_status & RIO_PORT_N_ERR_STS_PORT_OK) {

		if (!(rdev->rswitch->port_ok & (1 << portnum))) {
			rdev->rswitch->port_ok |= (1 << portnum);
			rio_set_port_lockout(rdev, portnum, 0);
			/* Schedule Insertion Service */
			pr_debug("RIO_PW: Device Insertion on [%s]-P%d\n",
			       rio_name(rdev), portnum);
		}

		/* Clear error-stopped states (if reported).
		 * Depending on the link partner state, two attempts
		 * may be needed for successful recovery.
		 */
		if (err_status & (RIO_PORT_N_ERR_STS_PW_OUT_ES |
				  RIO_PORT_N_ERR_STS_PW_INP_ES)) {
			if (rio_clr_err_stopped(rdev, portnum, err_status))
				rio_clr_err_stopped(rdev, portnum, 0);
		}
	}  else { /* if (err_status & RIO_PORT_N_ERR_STS_PORT_UNINIT) */

		if (rdev->rswitch->port_ok & (1 << portnum)) {
			rdev->rswitch->port_ok &= ~(1 << portnum);
			rio_set_port_lockout(rdev, portnum, 1);

			rio_write_config_32(rdev,
				rdev->phys_efptr +
					RIO_PORT_N_ACK_STS_CSR(portnum),
				RIO_PORT_N_ACK_CLEAR);

			/* Schedule Extraction Service */
			pr_debug("RIO_PW: Device Extraction on [%s]-P%d\n",
			       rio_name(rdev), portnum);
		}
	}

	rio_read_config_32(rdev,
		rdev->em_efptr + RIO_EM_PN_ERR_DETECT(portnum), &em_perrdet);
	if (em_perrdet) {
		pr_debug("RIO_PW: RIO_EM_P%d_ERR_DETECT=0x%08x\n",
			 portnum, em_perrdet);
		/* Clear EM Port N Error Detect CSR */
		rio_write_config_32(rdev,
			rdev->em_efptr + RIO_EM_PN_ERR_DETECT(portnum), 0);
	}

	rio_read_config_32(rdev,
		rdev->em_efptr + RIO_EM_LTL_ERR_DETECT, &em_ltlerrdet);
	if (em_ltlerrdet) {
		pr_debug("RIO_PW: RIO_EM_LTL_ERR_DETECT=0x%08x\n",
			 em_ltlerrdet);
		/* Clear EM L/T Layer Error Detect CSR */
		rio_write_config_32(rdev,
			rdev->em_efptr + RIO_EM_LTL_ERR_DETECT, 0);
	}

	/* Clear remaining error bits and Port-Write Pending bit */
	rio_write_config_32(rdev,
			rdev->phys_efptr + RIO_PORT_N_ERR_STS_CSR(portnum),
			err_status);

	return 0;
}
EXPORT_SYMBOL_GPL(rio_inb_pwrite_handler);

/**
 * rio_mport_get_efb - get pointer to next extended features block
 * @port: Master port to issue transaction
 * @local: Indicate a local master port or remote device access
 * @destid: Destination ID of the device
 * @hopcount: Number of switch hops to the device
 * @from: Offset of  current Extended Feature block header (if 0 starts
 * from	ExtFeaturePtr)
 */
u32
rio_mport_get_efb(struct rio_mport *port, int local, u16 destid,
		      u8 hopcount, u32 from)
{
	u32 reg_val;

	if (from == 0) {
		if (local)
			rio_local_read_config_32(port, RIO_ASM_INFO_CAR,
						 &reg_val);
		else
			rio_mport_read_config_32(port, destid, hopcount,
						 RIO_ASM_INFO_CAR, &reg_val);
		return reg_val & RIO_EXT_FTR_PTR_MASK;
	} else {
		if (local)
			rio_local_read_config_32(port, from, &reg_val);
		else
			rio_mport_read_config_32(port, destid, hopcount,
						 from, &reg_val);
		return RIO_GET_BLOCK_ID(reg_val);
	}
}
EXPORT_SYMBOL_GPL(rio_mport_get_efb);

/**
 * rio_mport_get_feature - query for devices' extended features
 * @port: Master port to issue transaction
 * @local: Indicate a local master port or remote device access
 * @destid: Destination ID of the device
 * @hopcount: Number of switch hops to the device
 * @ftr: Extended feature code
 *
 * Tell if a device supports a given RapidIO capability.
 * Returns the offset of the requested extended feature
 * block within the device's RIO configuration space or
 * 0 in case the device does not support it.  Possible
 * values for @ftr:
 *
 * %RIO_EFB_PAR_EP_ID		LP/LVDS EP Devices
 *
 * %RIO_EFB_PAR_EP_REC_ID	LP/LVDS EP Recovery Devices
 *
 * %RIO_EFB_PAR_EP_FREE_ID	LP/LVDS EP Free Devices
 *
 * %RIO_EFB_SER_EP_ID		LP/Serial EP Devices
 *
 * %RIO_EFB_SER_EP_REC_ID	LP/Serial EP Recovery Devices
 *
 * %RIO_EFB_SER_EP_FREE_ID	LP/Serial EP Free Devices
 */
u32
rio_mport_get_feature(struct rio_mport * port, int local, u16 destid,
		      u8 hopcount, int ftr)
{
	u32 asm_info, ext_ftr_ptr, ftr_header;

	if (local)
		rio_local_read_config_32(port, RIO_ASM_INFO_CAR, &asm_info);
	else
		rio_mport_read_config_32(port, destid, hopcount,
					 RIO_ASM_INFO_CAR, &asm_info);

	ext_ftr_ptr = asm_info & RIO_EXT_FTR_PTR_MASK;

	while (ext_ftr_ptr) {
		if (local)
			rio_local_read_config_32(port, ext_ftr_ptr,
						 &ftr_header);
		else
			rio_mport_read_config_32(port, destid, hopcount,
						 ext_ftr_ptr, &ftr_header);
		if (RIO_GET_BLOCK_ID(ftr_header) == ftr)
			return ext_ftr_ptr;
		if (!(ext_ftr_ptr = RIO_GET_BLOCK_PTR(ftr_header)))
			break;
	}

	return 0;
}
EXPORT_SYMBOL_GPL(rio_mport_get_feature);

/**
 * rio_get_asm - Begin or continue searching for a RIO device by vid/did/asm_vid/asm_did
 * @vid: RIO vid to match or %RIO_ANY_ID to match all vids
 * @did: RIO did to match or %RIO_ANY_ID to match all dids
 * @asm_vid: RIO asm_vid to match or %RIO_ANY_ID to match all asm_vids
 * @asm_did: RIO asm_did to match or %RIO_ANY_ID to match all asm_dids
 * @from: Previous RIO device found in search, or %NULL for new search
 *
 * Iterates through the list of known RIO devices. If a RIO device is
 * found with a matching @vid, @did, @asm_vid, @asm_did, the reference
 * count to the device is incrememted and a pointer to its device
 * structure is returned. Otherwise, %NULL is returned. A new search
 * is initiated by passing %NULL to the @from argument. Otherwise, if
 * @from is not %NULL, searches continue from next device on the global
 * list. The reference count for @from is always decremented if it is
 * not %NULL.
 */
struct rio_dev *rio_get_asm(u16 vid, u16 did,
			    u16 asm_vid, u16 asm_did, struct rio_dev *from)
{
	struct list_head *n;
	struct rio_dev *rdev;

	WARN_ON(in_interrupt());
	spin_lock(&rio_global_list_lock);
	n = from ? from->global_list.next : rio_devices.next;

	while (n && (n != &rio_devices)) {
		rdev = rio_dev_g(n);
		if ((vid == RIO_ANY_ID || rdev->vid == vid) &&
		    (did == RIO_ANY_ID || rdev->did == did) &&
		    (asm_vid == RIO_ANY_ID || rdev->asm_vid == asm_vid) &&
		    (asm_did == RIO_ANY_ID || rdev->asm_did == asm_did))
			goto exit;
		n = n->next;
	}
	rdev = NULL;
      exit:
	rio_dev_put(from);
	rdev = rio_dev_get(rdev);
	spin_unlock(&rio_global_list_lock);
	return rdev;
}

/**
 * rio_get_device - Begin or continue searching for a RIO device by vid/did
 * @vid: RIO vid to match or %RIO_ANY_ID to match all vids
 * @did: RIO did to match or %RIO_ANY_ID to match all dids
 * @from: Previous RIO device found in search, or %NULL for new search
 *
 * Iterates through the list of known RIO devices. If a RIO device is
 * found with a matching @vid and @did, the reference count to the
 * device is incrememted and a pointer to its device structure is returned.
 * Otherwise, %NULL is returned. A new search is initiated by passing %NULL
 * to the @from argument. Otherwise, if @from is not %NULL, searches
 * continue from next device on the global list. The reference count for
 * @from is always decremented if it is not %NULL.
 */
struct rio_dev *rio_get_device(u16 vid, u16 did, struct rio_dev *from)
{
	return rio_get_asm(vid, did, RIO_ANY_ID, RIO_ANY_ID, from);
}

/**
 * rio_std_route_add_entry - Add switch route table entry using standard
 *   registers defined in RIO specification rev.1.3
 * @mport: Master port to issue transaction
 * @destid: Destination ID of the device
 * @hopcount: Number of switch hops to the device
 * @table: routing table ID (global or port-specific)
 * @route_destid: destID entry in the RT
 * @route_port: destination port for specified destID
 */
static int
rio_std_route_add_entry(struct rio_mport *mport, u16 destid, u8 hopcount,
			u16 table, u16 route_destid, u8 route_port)
{
	if (table == RIO_GLOBAL_TABLE) {
		rio_mport_write_config_32(mport, destid, hopcount,
				RIO_STD_RTE_CONF_DESTID_SEL_CSR,
				(u32)route_destid);
		rio_mport_write_config_32(mport, destid, hopcount,
				RIO_STD_RTE_CONF_PORT_SEL_CSR,
				(u32)route_port);
	}

	udelay(10);
	return 0;
}

/**
 * rio_std_route_get_entry - Read switch route table entry (port number)
 *   associated with specified destID using standard registers defined in RIO
 *   specification rev.1.3
 * @mport: Master port to issue transaction
 * @destid: Destination ID of the device
 * @hopcount: Number of switch hops to the device
 * @table: routing table ID (global or port-specific)
 * @route_destid: destID entry in the RT
 * @route_port: returned destination port for specified destID
 */
static int
rio_std_route_get_entry(struct rio_mport *mport, u16 destid, u8 hopcount,
			u16 table, u16 route_destid, u8 *route_port)
{
	u32 result;

	if (table == RIO_GLOBAL_TABLE) {
		rio_mport_write_config_32(mport, destid, hopcount,
				RIO_STD_RTE_CONF_DESTID_SEL_CSR, route_destid);
		rio_mport_read_config_32(mport, destid, hopcount,
				RIO_STD_RTE_CONF_PORT_SEL_CSR, &result);

		*route_port = (u8)result;
	}

	return 0;
}

/**
 * rio_std_route_clr_table - Clear swotch route table using standard registers
 *   defined in RIO specification rev.1.3.
 * @mport: Master port to issue transaction
 * @destid: Destination ID of the device
 * @hopcount: Number of switch hops to the device
 * @table: routing table ID (global or port-specific)
 */
static int
rio_std_route_clr_table(struct rio_mport *mport, u16 destid, u8 hopcount,
			u16 table)
{
	u32 max_destid = 0xff;
	u32 i, pef, id_inc = 1, ext_cfg = 0;
	u32 port_sel = RIO_INVALID_ROUTE;

	if (table == RIO_GLOBAL_TABLE) {
		rio_mport_read_config_32(mport, destid, hopcount,
					 RIO_PEF_CAR, &pef);

		if (mport->sys_size) {
			rio_mport_read_config_32(mport, destid, hopcount,
						 RIO_SWITCH_RT_LIMIT,
						 &max_destid);
			max_destid &= RIO_RT_MAX_DESTID;
		}

		if (pef & RIO_PEF_EXT_RT) {
			ext_cfg = 0x80000000;
			id_inc = 4;
			port_sel = (RIO_INVALID_ROUTE << 24) |
				   (RIO_INVALID_ROUTE << 16) |
				   (RIO_INVALID_ROUTE << 8) |
				   RIO_INVALID_ROUTE;
		}

		for (i = 0; i <= max_destid;) {
			rio_mport_write_config_32(mport, destid, hopcount,
					RIO_STD_RTE_CONF_DESTID_SEL_CSR,
					ext_cfg | i);
			rio_mport_write_config_32(mport, destid, hopcount,
					RIO_STD_RTE_CONF_PORT_SEL_CSR,
					port_sel);
			i += id_inc;
		}
	}

	udelay(10);
	return 0;
}

/**
 * rio_lock_device - Acquires host device lock for specified device
 * @port: Master port to send transaction
 * @destid: Destination ID for device/switch
 * @hopcount: Hopcount to reach switch
 * @wait_ms: Max wait time in msec (0 = no timeout)
 *
 * Attepts to acquire host device lock for specified device
 * Returns 0 if device lock acquired or EINVAL if timeout expires.
 */
int rio_lock_device(struct rio_mport *port, u16 destid,
		    u8 hopcount, int wait_ms)
{
	u32 result;
	int tcnt = 0;

	/* Attempt to acquire device lock */
	rio_mport_write_config_32(port, destid, hopcount,
				  RIO_HOST_DID_LOCK_CSR, port->host_deviceid);
	rio_mport_read_config_32(port, destid, hopcount,
				 RIO_HOST_DID_LOCK_CSR, &result);

	while (result != port->host_deviceid) {
		if (wait_ms != 0 && tcnt == wait_ms) {
			pr_debug("RIO: timeout when locking device %x:%x\n",
				destid, hopcount);
			return -EINVAL;
		}

		/* Delay a bit */
		mdelay(1);
		tcnt++;
		/* Try to acquire device lock again */
		rio_mport_write_config_32(port, destid,
			hopcount,
			RIO_HOST_DID_LOCK_CSR,
			port->host_deviceid);
		rio_mport_read_config_32(port, destid,
			hopcount,
			RIO_HOST_DID_LOCK_CSR, &result);
	}

	return 0;
}
EXPORT_SYMBOL_GPL(rio_lock_device);

/**
 * rio_unlock_device - Releases host device lock for specified device
 * @port: Master port to send transaction
 * @destid: Destination ID for device/switch
 * @hopcount: Hopcount to reach switch
 *
 * Returns 0 if device lock released or EINVAL if fails.
 */
int rio_unlock_device(struct rio_mport *port, u16 destid, u8 hopcount)
{
	u32 result;

	/* Release device lock */
	rio_mport_write_config_32(port, destid,
				  hopcount,
				  RIO_HOST_DID_LOCK_CSR,
				  port->host_deviceid);
	rio_mport_read_config_32(port, destid, hopcount,
		RIO_HOST_DID_LOCK_CSR, &result);
	if ((result & 0xffff) != 0xffff) {
		pr_debug("RIO: badness when releasing device lock %x:%x\n",
			 destid, hopcount);
		return -EINVAL;
	}

	return 0;
}
EXPORT_SYMBOL_GPL(rio_unlock_device);

/**
 * rio_route_add_entry- Add a route entry to a switch routing table
 * @rdev: RIO device
 * @table: Routing table ID
 * @route_destid: Destination ID to be routed
 * @route_port: Port number to be routed
 * @lock: apply a hardware lock on switch device flag (1=lock, 0=no_lock)
 *
 * If available calls the switch specific add_entry() method to add a route
 * entry into a switch routing table. Otherwise uses standard RT update method
 * as defined by RapidIO specification. A specific routing table can be selected
 * using the @table argument if a switch has per port routing tables or
 * the standard (or global) table may be used by passing
 * %RIO_GLOBAL_TABLE in @table.
 *
 * Returns %0 on success or %-EINVAL on failure.
 */
int rio_route_add_entry(struct rio_dev *rdev,
			u16 table, u16 route_destid, u8 route_port, int lock)
{
	int rc = -EINVAL;
	struct rio_switch_ops *ops = rdev->rswitch->ops;

	if (lock) {
		rc = rio_lock_device(rdev->net->hport, rdev->destid,
				     rdev->hopcount, 1000);
		if (rc)
			return rc;
	}

	spin_lock(&rdev->rswitch->lock);

	if (ops == NULL || ops->add_entry == NULL) {
		rc = rio_std_route_add_entry(rdev->net->hport, rdev->destid,
					     rdev->hopcount, table,
					     route_destid, route_port);
	} else if (try_module_get(ops->owner)) {
		rc = ops->add_entry(rdev->net->hport, rdev->destid,
				    rdev->hopcount, table, route_destid,
				    route_port);
		module_put(ops->owner);
	}

	spin_unlock(&rdev->rswitch->lock);

	if (lock)
		rio_unlock_device(rdev->net->hport, rdev->destid,
				  rdev->hopcount);

	return rc;
}
EXPORT_SYMBOL_GPL(rio_route_add_entry);

/**
 * rio_route_get_entry- Read an entry from a switch routing table
 * @rdev: RIO device
 * @table: Routing table ID
 * @route_destid: Destination ID to be routed
 * @route_port: Pointer to read port number into
 * @lock: apply a hardware lock on switch device flag (1=lock, 0=no_lock)
 *
 * If available calls the switch specific get_entry() method to fetch a route
 * entry from a switch routing table. Otherwise uses standard RT read method
 * as defined by RapidIO specification. A specific routing table can be selected
 * using the @table argument if a switch has per port routing tables or
 * the standard (or global) table may be used by passing
 * %RIO_GLOBAL_TABLE in @table.
 *
 * Returns %0 on success or %-EINVAL on failure.
 */
int rio_route_get_entry(struct rio_dev *rdev, u16 table,
			u16 route_destid, u8 *route_port, int lock)
{
	int rc = -EINVAL;
	struct rio_switch_ops *ops = rdev->rswitch->ops;

	if (lock) {
		rc = rio_lock_device(rdev->net->hport, rdev->destid,
				     rdev->hopcount, 1000);
		if (rc)
			return rc;
	}

	spin_lock(&rdev->rswitch->lock);

	if (ops == NULL || ops->get_entry == NULL) {
		rc = rio_std_route_get_entry(rdev->net->hport, rdev->destid,
					     rdev->hopcount, table,
					     route_destid, route_port);
	} else if (try_module_get(ops->owner)) {
		rc = ops->get_entry(rdev->net->hport, rdev->destid,
				    rdev->hopcount, table, route_destid,
				    route_port);
		module_put(ops->owner);
	}

	spin_unlock(&rdev->rswitch->lock);

	if (lock)
		rio_unlock_device(rdev->net->hport, rdev->destid,
				  rdev->hopcount);
	return rc;
}
EXPORT_SYMBOL_GPL(rio_route_get_entry);

/**
 * rio_route_clr_table - Clear a switch routing table
 * @rdev: RIO device
 * @table: Routing table ID
 * @lock: apply a hardware lock on switch device flag (1=lock, 0=no_lock)
 *
 * If available calls the switch specific clr_table() method to clear a switch
 * routing table. Otherwise uses standard RT write method as defined by RapidIO
 * specification. A specific routing table can be selected using the @table
 * argument if a switch has per port routing tables or the standard (or global)
 * table may be used by passing %RIO_GLOBAL_TABLE in @table.
 *
 * Returns %0 on success or %-EINVAL on failure.
 */
int rio_route_clr_table(struct rio_dev *rdev, u16 table, int lock)
{
	int rc = -EINVAL;
	struct rio_switch_ops *ops = rdev->rswitch->ops;

	if (lock) {
		rc = rio_lock_device(rdev->net->hport, rdev->destid,
				     rdev->hopcount, 1000);
		if (rc)
			return rc;
	}

	spin_lock(&rdev->rswitch->lock);

	if (ops == NULL || ops->clr_table == NULL) {
		rc = rio_std_route_clr_table(rdev->net->hport, rdev->destid,
					     rdev->hopcount, table);
	} else if (try_module_get(ops->owner)) {
		rc = ops->clr_table(rdev->net->hport, rdev->destid,
				    rdev->hopcount, table);

		module_put(ops->owner);
	}

	spin_unlock(&rdev->rswitch->lock);

	if (lock)
		rio_unlock_device(rdev->net->hport, rdev->destid,
				  rdev->hopcount);

	return rc;
}
EXPORT_SYMBOL_GPL(rio_route_clr_table);

#ifdef CONFIG_RAPIDIO_DMA_ENGINE

static bool rio_chan_filter(struct dma_chan *chan, void *arg)
{
	struct rio_dev *rdev = arg;

	/* Check that DMA device belongs to the right MPORT */
	return (rdev->net->hport ==
		container_of(chan->device, struct rio_mport, dma));
}

/**
 * rio_request_dma - request RapidIO capable DMA channel that supports
 *   specified target RapidIO device.
 * @rdev: RIO device control structure
 *
 * Returns pointer to allocated DMA channel or NULL if failed.
 */
struct dma_chan *rio_request_dma(struct rio_dev *rdev)
{
	dma_cap_mask_t mask;
	struct dma_chan *dchan;

	dma_cap_zero(mask);
	dma_cap_set(DMA_SLAVE, mask);
	dchan = dma_request_channel(mask, rio_chan_filter, rdev);

	return dchan;
}
EXPORT_SYMBOL_GPL(rio_request_dma);

/**
 * rio_release_dma - release specified DMA channel
 * @dchan: DMA channel to release
 */
void rio_release_dma(struct dma_chan *dchan)
{
	dma_release_channel(dchan);
}
EXPORT_SYMBOL_GPL(rio_release_dma);

/**
 * rio_dma_prep_slave_sg - RapidIO specific wrapper
 *   for device_prep_slave_sg callback defined by DMAENGINE.
 * @rdev: RIO device control structure
 * @dchan: DMA channel to configure
 * @data: RIO specific data descriptor
 * @direction: DMA data transfer direction (TO or FROM the device)
 * @flags: dmaengine defined flags
 *
 * Initializes RapidIO capable DMA channel for the specified data transfer.
 * Uses DMA channel private extension to pass information related to remote
 * target RIO device.
 * Returns pointer to DMA transaction descriptor or NULL if failed.
 */
struct dma_async_tx_descriptor *rio_dma_prep_slave_sg(struct rio_dev *rdev,
	struct dma_chan *dchan, struct rio_dma_data *data,
	enum dma_transfer_direction direction, unsigned long flags)
{
	struct dma_async_tx_descriptor *txd = NULL;
	struct rio_dma_ext rio_ext;

	if (dchan->device->device_prep_slave_sg == NULL) {
		pr_err("%s: prep_rio_sg == NULL\n", __func__);
		return NULL;
	}

	rio_ext.destid = rdev->destid;
	rio_ext.rio_addr_u = data->rio_addr_u;
	rio_ext.rio_addr = data->rio_addr;
	rio_ext.wr_type = data->wr_type;

	txd = dmaengine_prep_rio_sg(dchan, data->sg, data->sg_len,
					direction, flags, &rio_ext);

	return txd;
}
EXPORT_SYMBOL_GPL(rio_dma_prep_slave_sg);

#endif /* CONFIG_RAPIDIO_DMA_ENGINE */

/**
 * rio_find_mport - find RIO mport by its ID
 * @mport_id: number (ID) of mport device
 *
 * Given a RIO mport number, the desired mport is located
 * in the global list of mports. If the mport is found, a pointer to its
 * data structure is returned.  If no mport is found, %NULL is returned.
 */
struct rio_mport *rio_find_mport(int mport_id)
{
	struct rio_mport *port;

	mutex_lock(&rio_mport_list_lock);
	list_for_each_entry(port, &rio_mports, node) {
		if (port->id == mport_id)
			goto found;
	}
	port = NULL;
found:
	mutex_unlock(&rio_mport_list_lock);

	return port;
}

/**
 * rio_register_scan - enumeration/discovery method registration interface
 * @mport_id: mport device ID for which fabric scan routine has to be set
 *            (RIO_MPORT_ANY = set for all available mports)
 * @scan_ops: enumeration/discovery control structure
 *
 * Assigns enumeration or discovery method to the specified mport device (or all
 * available mports if RIO_MPORT_ANY is specified).
 * Returns error if the mport already has an enumerator attached to it.
 * In case of RIO_MPORT_ANY ignores ports with valid scan routines and returns
 * an error if was unable to find at least one available mport.
 */
int rio_register_scan(int mport_id, struct rio_scan *scan_ops)
{
	struct rio_mport *port;
	int rc = -EBUSY;

	mutex_lock(&rio_mport_list_lock);
	list_for_each_entry(port, &rio_mports, node) {
		if (port->id == mport_id || mport_id == RIO_MPORT_ANY) {
			if (port->nscan && mport_id == RIO_MPORT_ANY)
				continue;
			else if (port->nscan)
				break;

			port->nscan = scan_ops;
			rc = 0;

			if (mport_id != RIO_MPORT_ANY)
				break;
		}
	}
	mutex_unlock(&rio_mport_list_lock);

	return rc;
}
EXPORT_SYMBOL_GPL(rio_register_scan);

/**
 * rio_unregister_scan - removes enumeration/discovery method from mport
 * @mport_id: mport device ID for which fabric scan routine has to be
 *            unregistered (RIO_MPORT_ANY = set for all available mports)
 *
 * Removes enumeration or discovery method assigned to the specified mport
 * device (or all available mports if RIO_MPORT_ANY is specified).
 */
int rio_unregister_scan(int mport_id)
{
	struct rio_mport *port;

	mutex_lock(&rio_mport_list_lock);
	list_for_each_entry(port, &rio_mports, node) {
		if (port->id == mport_id || mport_id == RIO_MPORT_ANY) {
			if (port->nscan)
				port->nscan = NULL;
			if (mport_id != RIO_MPORT_ANY)
				break;
		}
	}
	mutex_unlock(&rio_mport_list_lock);

	return 0;
}
EXPORT_SYMBOL_GPL(rio_unregister_scan);

static void rio_fixup_device(struct rio_dev *dev)
{
}

static int rio_init(void)
{
	struct rio_dev *dev = NULL;

	while ((dev = rio_get_device(RIO_ANY_ID, RIO_ANY_ID, dev)) != NULL) {
		rio_fixup_device(dev);
	}
	return 0;
}

static struct workqueue_struct *rio_wq;

struct rio_disc_work {
	struct work_struct	work;
	struct rio_mport	*mport;
};

static void disc_work_handler(struct work_struct *_work)
{
	struct rio_disc_work *work;

	work = container_of(_work, struct rio_disc_work, work);
	pr_debug("RIO: discovery work for mport %d %s\n",
		 work->mport->id, work->mport->name);
	work->mport->nscan->discover(work->mport, 0);
}

int rio_init_mports(void)
{
	struct rio_mport *port;
	struct rio_disc_work *work;
	int n = 0;

	if (!next_portid)
		return -ENODEV;

	/*
	 * First, run enumerations and check if we need to perform discovery
	 * on any of the registered mports.
	 */
	mutex_lock(&rio_mport_list_lock);
	list_for_each_entry(port, &rio_mports, node) {
		if (port->host_deviceid >= 0) {
			if (port->nscan)
				port->nscan->enumerate(port, 0);
		} else
			n++;
	}
	mutex_unlock(&rio_mport_list_lock);

	if (!n)
		goto no_disc;

	/*
	 * If we have mports that require discovery schedule a discovery work
	 * for each of them. If the code below fails to allocate needed
	 * resources, exit without error to keep results of enumeration
	 * process (if any).
	 * TODO: Implement restart of dicovery process for all or
	 * individual discovering mports.
	 */
	rio_wq = alloc_workqueue("riodisc", 0, 0);
	if (!rio_wq) {
		pr_err("RIO: unable allocate rio_wq\n");
		goto no_disc;
	}

	work = kcalloc(n, sizeof *work, GFP_KERNEL);
	if (!work) {
		pr_err("RIO: no memory for work struct\n");
		destroy_workqueue(rio_wq);
		goto no_disc;
	}

	n = 0;
	mutex_lock(&rio_mport_list_lock);
	list_for_each_entry(port, &rio_mports, node) {
		if (port->host_deviceid < 0 && port->nscan) {
			work[n].mport = port;
			INIT_WORK(&work[n].work, disc_work_handler);
			queue_work(rio_wq, &work[n].work);
			n++;
		}
	}
	mutex_unlock(&rio_mport_list_lock);

	flush_workqueue(rio_wq);
	pr_debug("RIO: destroy discovery workqueue\n");
	destroy_workqueue(rio_wq);
	kfree(work);

no_disc:
	rio_init();

	return 0;
}

static int hdids[RIO_MAX_MPORTS + 1];

static int rio_get_hdid(int index)
{
	if (!hdids[0] || hdids[0] <= index || index >= RIO_MAX_MPORTS)
		return -1;

	return hdids[index + 1];
}

static int rio_hdid_setup(char *str)
{
	(void)get_options(str, ARRAY_SIZE(hdids), hdids);
	return 1;
}

__setup("riohdid=", rio_hdid_setup);

int rio_register_mport(struct rio_mport *port)
{
	if (next_portid >= RIO_MAX_MPORTS) {
		pr_err("RIO: reached specified max number of mports\n");
		return 1;
	}

	port->id = next_portid++;
	port->host_deviceid = rio_get_hdid(port->id);
	port->nscan = NULL;
	mutex_lock(&rio_mport_list_lock);
	list_add_tail(&port->node, &rio_mports);
	mutex_unlock(&rio_mport_list_lock);
	return 0;
}

EXPORT_SYMBOL_GPL(rio_local_get_device_id);
EXPORT_SYMBOL_GPL(rio_get_device);
EXPORT_SYMBOL_GPL(rio_get_asm);
EXPORT_SYMBOL_GPL(rio_request_inb_dbell);
EXPORT_SYMBOL_GPL(rio_release_inb_dbell);
EXPORT_SYMBOL_GPL(rio_request_outb_dbell);
EXPORT_SYMBOL_GPL(rio_release_outb_dbell);
EXPORT_SYMBOL_GPL(rio_request_inb_mbox);
EXPORT_SYMBOL_GPL(rio_release_inb_mbox);
EXPORT_SYMBOL_GPL(rio_request_outb_mbox);
EXPORT_SYMBOL_GPL(rio_release_outb_mbox);
EXPORT_SYMBOL_GPL(rio_init_mports);
OpenPOWER on IntegriCloud