aboutsummaryrefslogtreecommitdiff
path: root/drivers/net/ethernet/3com/3c515.c
blob: 94c656f5a05ddbe9a09e505009466961a8e119a2 (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
/*
	Written 1997-1998 by Donald Becker.

	This software may be used and distributed according to the terms
	of the GNU General Public License, incorporated herein by reference.

	This driver is for the 3Com ISA EtherLink XL "Corkscrew" 3c515 ethercard.

	The author may be reached as becker@scyld.com, or C/O
	Scyld Computing Corporation
	410 Severn Ave., Suite 210
	Annapolis MD 21403


	2000/2/2- Added support for kernel-level ISAPnP
		by Stephen Frost <sfrost@snowman.net> and Alessandro Zummo
	Cleaned up for 2.3.x/softnet by Jeff Garzik and Alan Cox.

	2001/11/17 - Added ethtool support (jgarzik)

	2002/10/28 - Locking updates for 2.5 (alan@lxorguk.ukuu.org.uk)

*/

#define DRV_NAME		"3c515"
#define DRV_VERSION		"0.99t-ac"
#define DRV_RELDATE		"28-Oct-2002"

static char *version =
DRV_NAME ".c:v" DRV_VERSION " " DRV_RELDATE " becker@scyld.com and others\n";

#define CORKSCREW 1

/* "Knobs" that adjust features and parameters. */
/* Set the copy breakpoint for the copy-only-tiny-frames scheme.
   Setting to > 1512 effectively disables this feature. */
static int rx_copybreak = 200;

/* Allow setting MTU to a larger size, bypassing the normal ethernet setup. */
static const int mtu = 1500;

/* Maximum events (Rx packets, etc.) to handle at each interrupt. */
static int max_interrupt_work = 20;

/* Enable the automatic media selection code -- usually set. */
#define AUTOMEDIA 1

/* Allow the use of fragment bus master transfers instead of only
   programmed-I/O for Vortex cards.  Full-bus-master transfers are always
   enabled by default on Boomerang cards.  If VORTEX_BUS_MASTER is defined,
   the feature may be turned on using 'options'. */
#define VORTEX_BUS_MASTER

/* A few values that may be tweaked. */
/* Keep the ring sizes a power of two for efficiency. */
#define TX_RING_SIZE	16
#define RX_RING_SIZE	16
#define PKT_BUF_SZ		1536	/* Size of each temporary Rx buffer. */

#include <linux/module.h>
#include <linux/isapnp.h>
#include <linux/kernel.h>
#include <linux/netdevice.h>
#include <linux/string.h>
#include <linux/errno.h>
#include <linux/in.h>
#include <linux/ioport.h>
#include <linux/skbuff.h>
#include <linux/etherdevice.h>
#include <linux/interrupt.h>
#include <linux/timer.h>
#include <linux/ethtool.h>
#include <linux/bitops.h>

#include <asm/uaccess.h>
#include <asm/io.h>
#include <asm/dma.h>

#define NEW_MULTICAST
#include <linux/delay.h>

#define MAX_UNITS 8

MODULE_AUTHOR("Donald Becker <becker@scyld.com>");
MODULE_DESCRIPTION("3Com 3c515 Corkscrew driver");
MODULE_LICENSE("GPL");
MODULE_VERSION(DRV_VERSION);

/* "Knobs" for adjusting internal parameters. */
/* Put out somewhat more debugging messages. (0 - no msg, 1 minimal msgs). */
#define DRIVER_DEBUG 1
/* Some values here only for performance evaluation and path-coverage
   debugging. */
static int rx_nocopy, rx_copy, queued_packet;

/* Number of times to check to see if the Tx FIFO has space, used in some
   limited cases. */
#define WAIT_TX_AVAIL 200

/* Operational parameter that usually are not changed. */
#define TX_TIMEOUT  ((4*HZ)/10)	/* Time in jiffies before concluding Tx hung */

/* The size here is somewhat misleading: the Corkscrew also uses the ISA
   aliased registers at <base>+0x400.
   */
#define CORKSCREW_TOTAL_SIZE 0x20

#ifdef DRIVER_DEBUG
static int corkscrew_debug = DRIVER_DEBUG;
#else
static int corkscrew_debug = 1;
#endif

#define CORKSCREW_ID 10

/*
				Theory of Operation

I. Board Compatibility

This device driver is designed for the 3Com 3c515 ISA Fast EtherLink XL,
3Com's ISA bus adapter for Fast Ethernet.  Due to the unique I/O port layout,
it's not practical to integrate this driver with the other EtherLink drivers.

II. Board-specific settings

The Corkscrew has an EEPROM for configuration, but no special settings are
needed for Linux.

III. Driver operation

The 3c515 series use an interface that's very similar to the 3c900 "Boomerang"
PCI cards, with the bus master interface extensively modified to work with
the ISA bus.

The card is capable of full-bus-master transfers with separate
lists of transmit and receive descriptors, similar to the AMD LANCE/PCnet,
DEC Tulip and Intel Speedo3.

This driver uses a "RX_COPYBREAK" scheme rather than a fixed intermediate
receive buffer.  This scheme allocates full-sized skbuffs as receive
buffers.  The value RX_COPYBREAK is used as the copying breakpoint: it is
chosen to trade-off the memory wasted by passing the full-sized skbuff to
the queue layer for all frames vs. the copying cost of copying a frame to a
correctly-sized skbuff.


IIIC. Synchronization
The driver runs as two independent, single-threaded flows of control.  One
is the send-packet routine, which enforces single-threaded use by the netif
layer.  The other thread is the interrupt handler, which is single
threaded by the hardware and other software.

IV. Notes

Thanks to Terry Murphy of 3Com for providing documentation and a development
board.

The names "Vortex", "Boomerang" and "Corkscrew" are the internal 3Com
project names.  I use these names to eliminate confusion -- 3Com product
numbers and names are very similar and often confused.

The new chips support both ethernet (1.5K) and FDDI (4.5K) frame sizes!
This driver only supports ethernet frames because of the recent MTU limit
of 1.5K, but the changes to support 4.5K are minimal.
*/

/* Operational definitions.
   These are not used by other compilation units and thus are not
   exported in a ".h" file.

   First the windows.  There are eight register windows, with the command
   and status registers available in each.
   */
#define EL3WINDOW(win_num) outw(SelectWindow + (win_num), ioaddr + EL3_CMD)
#define EL3_CMD 0x0e
#define EL3_STATUS 0x0e

/* The top five bits written to EL3_CMD are a command, the lower
   11 bits are the parameter, if applicable.
   Note that 11 parameters bits was fine for ethernet, but the new chips
   can handle FDDI length frames (~4500 octets) and now parameters count
   32-bit 'Dwords' rather than octets. */

enum corkscrew_cmd {
	TotalReset = 0 << 11, SelectWindow = 1 << 11, StartCoax = 2 << 11,
	RxDisable = 3 << 11, RxEnable = 4 << 11, RxReset = 5 << 11,
	UpStall = 6 << 11, UpUnstall = (6 << 11) + 1, DownStall = (6 << 11) + 2,
	DownUnstall = (6 << 11) + 3, RxDiscard = 8 << 11, TxEnable = 9 << 11,
	TxDisable = 10 << 11, TxReset = 11 << 11, FakeIntr = 12 << 11,
	AckIntr = 13 << 11, SetIntrEnb = 14 << 11, SetStatusEnb = 15 << 11,
	SetRxFilter = 16 << 11, SetRxThreshold = 17 << 11,
	SetTxThreshold = 18 << 11, SetTxStart = 19 << 11, StartDMAUp = 20 << 11,
	StartDMADown = (20 << 11) + 1, StatsEnable = 21 << 11,
	StatsDisable = 22 << 11, StopCoax = 23 << 11,
};

/* The SetRxFilter command accepts the following classes: */
enum RxFilter {
	RxStation = 1, RxMulticast = 2, RxBroadcast = 4, RxProm = 8
};

/* Bits in the general status register. */
enum corkscrew_status {
	IntLatch = 0x0001, AdapterFailure = 0x0002, TxComplete = 0x0004,
	TxAvailable = 0x0008, RxComplete = 0x0010, RxEarly = 0x0020,
	IntReq = 0x0040, StatsFull = 0x0080,
	DMADone = 1 << 8, DownComplete = 1 << 9, UpComplete = 1 << 10,
	DMAInProgress = 1 << 11,	/* DMA controller is still busy. */
	CmdInProgress = 1 << 12,	/* EL3_CMD is still busy. */
};

/* Register window 1 offsets, the window used in normal operation.
   On the Corkscrew this window is always mapped at offsets 0x10-0x1f. */
enum Window1 {
	TX_FIFO = 0x10, RX_FIFO = 0x10, RxErrors = 0x14,
	RxStatus = 0x18, Timer = 0x1A, TxStatus = 0x1B,
	TxFree = 0x1C,		/* Remaining free bytes in Tx buffer. */
};
enum Window0 {
	Wn0IRQ = 0x08,
#if defined(CORKSCREW)
	Wn0EepromCmd = 0x200A,	/* Corkscrew EEPROM command register. */
	Wn0EepromData = 0x200C,	/* Corkscrew EEPROM results register. */
#else
	Wn0EepromCmd = 10,	/* Window 0: EEPROM command register. */
	Wn0EepromData = 12,	/* Window 0: EEPROM results register. */
#endif
};
enum Win0_EEPROM_bits {
	EEPROM_Read = 0x80, EEPROM_WRITE = 0x40, EEPROM_ERASE = 0xC0,
	EEPROM_EWENB = 0x30,	/* Enable erasing/writing for 10 msec. */
	EEPROM_EWDIS = 0x00,	/* Disable EWENB before 10 msec timeout. */
};

/* EEPROM locations. */
enum eeprom_offset {
	PhysAddr01 = 0, PhysAddr23 = 1, PhysAddr45 = 2, ModelID = 3,
	EtherLink3ID = 7,
};

enum Window3 {			/* Window 3: MAC/config bits. */
	Wn3_Config = 0, Wn3_MAC_Ctrl = 6, Wn3_Options = 8,
};
enum wn3_config {
	Ram_size = 7,
	Ram_width = 8,
	Ram_speed = 0x30,
	Rom_size = 0xc0,
	Ram_split_shift = 16,
	Ram_split = 3 << Ram_split_shift,
	Xcvr_shift = 20,
	Xcvr = 7 << Xcvr_shift,
	Autoselect = 0x1000000,
};

enum Window4 {
	Wn4_NetDiag = 6, Wn4_Media = 10,	/* Window 4: Xcvr/media bits. */
};
enum Win4_Media_bits {
	Media_SQE = 0x0008,	/* Enable SQE error counting for AUI. */
	Media_10TP = 0x00C0,	/* Enable link beat and jabber for 10baseT. */
	Media_Lnk = 0x0080,	/* Enable just link beat for 100TX/100FX. */
	Media_LnkBeat = 0x0800,
};
enum Window7 {			/* Window 7: Bus Master control. */
	Wn7_MasterAddr = 0, Wn7_MasterLen = 6, Wn7_MasterStatus = 12,
};

/* Boomerang-style bus master control registers.  Note ISA aliases! */
enum MasterCtrl {
	PktStatus = 0x400, DownListPtr = 0x404, FragAddr = 0x408, FragLen =
	    0x40c,
	TxFreeThreshold = 0x40f, UpPktStatus = 0x410, UpListPtr = 0x418,
};

/* The Rx and Tx descriptor lists.
   Caution Alpha hackers: these types are 32 bits!  Note also the 8 byte
   alignment contraint on tx_ring[] and rx_ring[]. */
struct boom_rx_desc {
	u32 next;
	s32 status;
	u32 addr;
	s32 length;
};

/* Values for the Rx status entry. */
enum rx_desc_status {
	RxDComplete = 0x00008000, RxDError = 0x4000,
	/* See boomerang_rx() for actual error bits */
};

struct boom_tx_desc {
	u32 next;
	s32 status;
	u32 addr;
	s32 length;
};

struct corkscrew_private {
	const char *product_name;
	struct list_head list;
	struct net_device *our_dev;
	/* The Rx and Tx rings are here to keep them quad-word-aligned. */
	struct boom_rx_desc rx_ring[RX_RING_SIZE];
	struct boom_tx_desc tx_ring[TX_RING_SIZE];
	/* The addresses of transmit- and receive-in-place skbuffs. */
	struct sk_buff *rx_skbuff[RX_RING_SIZE];
	struct sk_buff *tx_skbuff[TX_RING_SIZE];
	unsigned int cur_rx, cur_tx;	/* The next free ring entry */
	unsigned int dirty_rx, dirty_tx;/* The ring entries to be free()ed. */
	struct sk_buff *tx_skb;	/* Packet being eaten by bus master ctrl.  */
	struct timer_list timer;	/* Media selection timer. */
	int capabilities	;	/* Adapter capabilities word. */
	int options;			/* User-settable misc. driver options. */
	int last_rx_packets;		/* For media autoselection. */
	unsigned int available_media:8,	/* From Wn3_Options */
		media_override:3,	/* Passed-in media type. */
		default_media:3,	/* Read from the EEPROM. */
		full_duplex:1, autoselect:1, bus_master:1,	/* Vortex can only do a fragment bus-m. */
		full_bus_master_tx:1, full_bus_master_rx:1,	/* Boomerang  */
		tx_full:1;
	spinlock_t lock;
	struct device *dev;
};

/* The action to take with a media selection timer tick.
   Note that we deviate from the 3Com order by checking 10base2 before AUI.
 */
enum xcvr_types {
	XCVR_10baseT = 0, XCVR_AUI, XCVR_10baseTOnly, XCVR_10base2, XCVR_100baseTx,
	XCVR_100baseFx, XCVR_MII = 6, XCVR_Default = 8,
};

static struct media_table {
	char *name;
	unsigned int media_bits:16,	/* Bits to set in Wn4_Media register. */
		mask:8,			/* The transceiver-present bit in Wn3_Config. */
		next:8;			/* The media type to try next. */
	short wait;			/* Time before we check media status. */
} media_tbl[] = {
	{ "10baseT", Media_10TP, 0x08, XCVR_10base2, (14 * HZ) / 10 },
	{ "10Mbs AUI", Media_SQE, 0x20, XCVR_Default, (1 * HZ) / 10},
	{ "undefined", 0, 0x80, XCVR_10baseT, 10000},
	{ "10base2", 0, 0x10, XCVR_AUI, (1 * HZ) / 10},
	{ "100baseTX", Media_Lnk, 0x02, XCVR_100baseFx, (14 * HZ) / 10},
	{ "100baseFX", Media_Lnk, 0x04, XCVR_MII, (14 * HZ) / 10},
	{ "MII", 0, 0x40, XCVR_10baseT, 3 * HZ},
	{ "undefined", 0, 0x01, XCVR_10baseT, 10000},
	{ "Default", 0, 0xFF, XCVR_10baseT, 10000},
};

#ifdef __ISAPNP__
static struct isapnp_device_id corkscrew_isapnp_adapters[] = {
	{	ISAPNP_ANY_ID, ISAPNP_ANY_ID,
		ISAPNP_VENDOR('T', 'C', 'M'), ISAPNP_FUNCTION(0x5051),
		(long) "3Com Fast EtherLink ISA" },
	{ }	/* terminate list */
};

MODULE_DEVICE_TABLE(isapnp, corkscrew_isapnp_adapters);

static int nopnp;
#endif /* __ISAPNP__ */

static struct net_device *corkscrew_scan(int unit);
static int corkscrew_setup(struct net_device *dev, int ioaddr,
			    struct pnp_dev *idev, int card_number);
static int corkscrew_open(struct net_device *dev);
static void corkscrew_timer(unsigned long arg);
static netdev_tx_t corkscrew_start_xmit(struct sk_buff *skb,
					struct net_device *dev);
static int corkscrew_rx(struct net_device *dev);
static void corkscrew_timeout(struct net_device *dev);
static int boomerang_rx(struct net_device *dev);
static irqreturn_t corkscrew_interrupt(int irq, void *dev_id);
static int corkscrew_close(struct net_device *dev);
static void update_stats(int addr, struct net_device *dev);
static struct net_device_stats *corkscrew_get_stats(struct net_device *dev);
static void set_rx_mode(struct net_device *dev);
static const struct ethtool_ops netdev_ethtool_ops;


/*
   Unfortunately maximizing the shared code between the integrated and
   module version of the driver results in a complicated set of initialization
   procedures.
   init_module() -- modules /  tc59x_init()  -- built-in
		The wrappers for corkscrew_scan()
   corkscrew_scan()  		 The common routine that scans for PCI and EISA cards
   corkscrew_found_device() Allocate a device structure when we find a card.
					Different versions exist for modules and built-in.
   corkscrew_probe1()		Fill in the device structure -- this is separated
					so that the modules code can put it in dev->init.
*/
/* This driver uses 'options' to pass the media type, full-duplex flag, etc. */
/* Note: this is the only limit on the number of cards supported!! */
static int options[MAX_UNITS] = { -1, -1, -1, -1, -1, -1, -1, -1, };

#ifdef MODULE
static int debug = -1;

module_param(debug, int, 0);
module_param_array(options, int, NULL, 0);
module_param(rx_copybreak, int, 0);
module_param(max_interrupt_work, int, 0);
MODULE_PARM_DESC(debug, "3c515 debug level (0-6)");
MODULE_PARM_DESC(options, "3c515: Bits 0-2: media type, bit 3: full duplex, bit 4: bus mastering");
MODULE_PARM_DESC(rx_copybreak, "3c515 copy breakpoint for copy-only-tiny-frames");
MODULE_PARM_DESC(max_interrupt_work, "3c515 maximum events handled per interrupt");

/* A list of all installed Vortex devices, for removing the driver module. */
/* we will need locking (and refcounting) if we ever use it for more */
static LIST_HEAD(root_corkscrew_dev);

int init_module(void)
{
	int found = 0;
	if (debug >= 0)
		corkscrew_debug = debug;
	if (corkscrew_debug)
		pr_debug("%s", version);
	while (corkscrew_scan(-1))
		found++;
	return found ? 0 : -ENODEV;
}

#else
struct net_device *tc515_probe(int unit)
{
	struct net_device *dev = corkscrew_scan(unit);
	static int printed;

	if (!dev)
		return ERR_PTR(-ENODEV);

	if (corkscrew_debug > 0 && !printed) {
		printed = 1;
		pr_debug("%s", version);
	}

	return dev;
}
#endif				/* not MODULE */

static int check_device(unsigned ioaddr)
{
	int timer;

	if (!request_region(ioaddr, CORKSCREW_TOTAL_SIZE, "3c515"))
		return 0;
	/* Check the resource configuration for a matching ioaddr. */
	if ((inw(ioaddr + 0x2002) & 0x1f0) != (ioaddr & 0x1f0)) {
		release_region(ioaddr, CORKSCREW_TOTAL_SIZE);
		return 0;
	}
	/* Verify by reading the device ID from the EEPROM. */
	outw(EEPROM_Read + 7, ioaddr + Wn0EepromCmd);
	/* Pause for at least 162 us. for the read to take place. */
	for (timer = 4; timer >= 0; timer--) {
		udelay(162);
		if ((inw(ioaddr + Wn0EepromCmd) & 0x0200) == 0)
			break;
	}
	if (inw(ioaddr + Wn0EepromData) != 0x6d50) {
		release_region(ioaddr, CORKSCREW_TOTAL_SIZE);
		return 0;
	}
	return 1;
}

static void cleanup_card(struct net_device *dev)
{
	struct corkscrew_private *vp = netdev_priv(dev);
	list_del_init(&vp->list);
	if (dev->dma)
		free_dma(dev->dma);
	outw(TotalReset, dev->base_addr + EL3_CMD);
	release_region(dev->base_addr, CORKSCREW_TOTAL_SIZE);
	if (vp->dev)
		pnp_device_detach(to_pnp_dev(vp->dev));
}

static struct net_device *corkscrew_scan(int unit)
{
	struct net_device *dev;
	static int cards_found = 0;
	static int ioaddr;
	int err;
#ifdef __ISAPNP__
	short i;
	static int pnp_cards;
#endif

	dev = alloc_etherdev(sizeof(struct corkscrew_private));
	if (!dev)
		return ERR_PTR(-ENOMEM);

	if (unit >= 0) {
		sprintf(dev->name, "eth%d", unit);
		netdev_boot_setup_check(dev);
	}

#ifdef __ISAPNP__
	if(nopnp == 1)
		goto no_pnp;
	for(i=0; corkscrew_isapnp_adapters[i].vendor != 0; i++) {
		struct pnp_dev *idev = NULL;
		int irq;
		while((idev = pnp_find_dev(NULL,
					   corkscrew_isapnp_adapters[i].vendor,
					   corkscrew_isapnp_adapters[i].function,
					   idev))) {

			if (pnp_device_attach(idev) < 0)
				continue;
			if (pnp_activate_dev(idev) < 0) {
				pr_warning("pnp activate failed (out of resources?)\n");
				pnp_device_detach(idev);
				continue;
			}
			if (!pnp_port_valid(idev, 0) || !pnp_irq_valid(idev, 0)) {
				pnp_device_detach(idev);
				continue;
			}
			ioaddr = pnp_port_start(idev, 0);
			irq = pnp_irq(idev, 0);
			if (!check_device(ioaddr)) {
				pnp_device_detach(idev);
				continue;
			}
			if(corkscrew_debug)
				pr_debug("ISAPNP reports %s at i/o 0x%x, irq %d\n",
					(char*) corkscrew_isapnp_adapters[i].driver_data, ioaddr, irq);
			pr_info("3c515 Resource configuration register %#4.4x, DCR %4.4x.\n",
		     		inl(ioaddr + 0x2002), inw(ioaddr + 0x2000));
			/* irq = inw(ioaddr + 0x2002) & 15; */ /* Use the irq from isapnp */
			SET_NETDEV_DEV(dev, &idev->dev);
			pnp_cards++;
			err = corkscrew_setup(dev, ioaddr, idev, cards_found++);
			if (!err)
				return dev;
			cleanup_card(dev);
		}
	}
no_pnp:
#endif /* __ISAPNP__ */

	/* Check all locations on the ISA bus -- evil! */
	for (ioaddr = 0x100; ioaddr < 0x400; ioaddr += 0x20) {
		if (!check_device(ioaddr))
			continue;

		pr_info("3c515 Resource configuration register %#4.4x, DCR %4.4x.\n",
		     inl(ioaddr + 0x2002), inw(ioaddr + 0x2000));
		err = corkscrew_setup(dev, ioaddr, NULL, cards_found++);
		if (!err)
			return dev;
		cleanup_card(dev);
	}
	free_netdev(dev);
	return NULL;
}


static const struct net_device_ops netdev_ops = {
	.ndo_open		= corkscrew_open,
	.ndo_stop		= corkscrew_close,
	.ndo_start_xmit		= corkscrew_start_xmit,
	.ndo_tx_timeout		= corkscrew_timeout,
	.ndo_get_stats		= corkscrew_get_stats,
	.ndo_set_rx_mode	= set_rx_mode,
	.ndo_change_mtu		= eth_change_mtu,
	.ndo_set_mac_address 	= eth_mac_addr,
	.ndo_validate_addr	= eth_validate_addr,
};


static int corkscrew_setup(struct net_device *dev, int ioaddr,
			    struct pnp_dev *idev, int card_number)
{
	struct corkscrew_private *vp = netdev_priv(dev);
	unsigned int eeprom[0x40], checksum = 0;	/* EEPROM contents */
	int i;
	int irq;

#ifdef __ISAPNP__
	if (idev) {
		irq = pnp_irq(idev, 0);
		vp->dev = &idev->dev;
	} else {
		irq = inw(ioaddr + 0x2002) & 15;
	}
#else
	irq = inw(ioaddr + 0x2002) & 15;
#endif

	dev->base_addr = ioaddr;
	dev->irq = irq;
	dev->dma = inw(ioaddr + 0x2000) & 7;
	vp->product_name = "3c515";
	vp->options = dev->mem_start;
	vp->our_dev = dev;

	if (!vp->options) {
		 if (card_number >= MAX_UNITS)
			vp->options = -1;
		else
			vp->options = options[card_number];
	}

	if (vp->options >= 0) {
		vp->media_override = vp->options & 7;
		if (vp->media_override == 2)
			vp->media_override = 0;
		vp->full_duplex = (vp->options & 8) ? 1 : 0;
		vp->bus_master = (vp->options & 16) ? 1 : 0;
	} else {
		vp->media_override = 7;
		vp->full_duplex = 0;
		vp->bus_master = 0;
	}
#ifdef MODULE
	list_add(&vp->list, &root_corkscrew_dev);
#endif

	pr_info("%s: 3Com %s at %#3x,", dev->name, vp->product_name, ioaddr);

	spin_lock_init(&vp->lock);

	/* Read the station address from the EEPROM. */
	EL3WINDOW(0);
	for (i = 0; i < 0x18; i++) {
		__be16 *phys_addr = (__be16 *) dev->dev_addr;
		int timer;
		outw(EEPROM_Read + i, ioaddr + Wn0EepromCmd);
		/* Pause for at least 162 us. for the read to take place. */
		for (timer = 4; timer >= 0; timer--) {
			udelay(162);
			if ((inw(ioaddr + Wn0EepromCmd) & 0x0200) == 0)
				break;
		}
		eeprom[i] = inw(ioaddr + Wn0EepromData);
		checksum ^= eeprom[i];
		if (i < 3)
			phys_addr[i] = htons(eeprom[i]);
	}
	checksum = (checksum ^ (checksum >> 8)) & 0xff;
	if (checksum != 0x00)
		pr_cont(" ***INVALID CHECKSUM %4.4x*** ", checksum);
	pr_cont(" %pM", dev->dev_addr);
	if (eeprom[16] == 0x11c7) {	/* Corkscrew */
		if (request_dma(dev->dma, "3c515")) {
			pr_cont(", DMA %d allocation failed", dev->dma);
			dev->dma = 0;
		} else
			pr_cont(", DMA %d", dev->dma);
	}
	pr_cont(", IRQ %d\n", dev->irq);
	/* Tell them about an invalid IRQ. */
	if (corkscrew_debug && (dev->irq <= 0 || dev->irq > 15))
		pr_warning(" *** Warning: this IRQ is unlikely to work! ***\n");

	{
		static const char * const ram_split[] = {
			"5:3", "3:1", "1:1", "3:5"
		};
		__u32 config;
		EL3WINDOW(3);
		vp->available_media = inw(ioaddr + Wn3_Options);
		config = inl(ioaddr + Wn3_Config);
		if (corkscrew_debug > 1)
			pr_info("  Internal config register is %4.4x, transceivers %#x.\n",
				config, inw(ioaddr + Wn3_Options));
		pr_info("  %dK %s-wide RAM %s Rx:Tx split, %s%s interface.\n",
			8 << config & Ram_size,
			config & Ram_width ? "word" : "byte",
			ram_split[(config & Ram_split) >> Ram_split_shift],
			config & Autoselect ? "autoselect/" : "",
			media_tbl[(config & Xcvr) >> Xcvr_shift].name);
		vp->default_media = (config & Xcvr) >> Xcvr_shift;
		vp->autoselect = config & Autoselect ? 1 : 0;
		dev->if_port = vp->default_media;
	}
	if (vp->media_override != 7) {
		pr_info("  Media override to transceiver type %d (%s).\n",
		       vp->media_override,
		       media_tbl[vp->media_override].name);
		dev->if_port = vp->media_override;
	}

	vp->capabilities = eeprom[16];
	vp->full_bus_master_tx = (vp->capabilities & 0x20) ? 1 : 0;
	/* Rx is broken at 10mbps, so we always disable it. */
	/* vp->full_bus_master_rx = 0; */
	vp->full_bus_master_rx = (vp->capabilities & 0x20) ? 1 : 0;

	/* The 3c51x-specific entries in the device structure. */
	dev->netdev_ops = &netdev_ops;
	dev->watchdog_timeo = (400 * HZ) / 1000;
	dev->ethtool_ops = &netdev_ethtool_ops;

	return register_netdev(dev);
}


static int corkscrew_open(struct net_device *dev)
{
	int ioaddr = dev->base_addr;
	struct corkscrew_private *vp = netdev_priv(dev);
	__u32 config;
	int i;

	/* Before initializing select the active media port. */
	EL3WINDOW(3);
	if (vp->full_duplex)
		outb(0x20, ioaddr + Wn3_MAC_Ctrl);	/* Set the full-duplex bit. */
	config = inl(ioaddr + Wn3_Config);

	if (vp->media_override != 7) {
		if (corkscrew_debug > 1)
			pr_info("%s: Media override to transceiver %d (%s).\n",
				dev->name, vp->media_override,
				media_tbl[vp->media_override].name);
		dev->if_port = vp->media_override;
	} else if (vp->autoselect) {
		/* Find first available media type, starting with 100baseTx. */
		dev->if_port = 4;
		while (!(vp->available_media & media_tbl[dev->if_port].mask))
			dev->if_port = media_tbl[dev->if_port].next;

		if (corkscrew_debug > 1)
			pr_debug("%s: Initial media type %s.\n",
			       dev->name, media_tbl[dev->if_port].name);

		init_timer(&vp->timer);
		vp->timer.expires = jiffies + media_tbl[dev->if_port].wait;
		vp->timer.data = (unsigned long) dev;
		vp->timer.function = corkscrew_timer;	/* timer handler */
		add_timer(&vp->timer);
	} else
		dev->if_port = vp->default_media;

	config = (config & ~Xcvr) | (dev->if_port << Xcvr_shift);
	outl(config, ioaddr + Wn3_Config);

	if (corkscrew_debug > 1) {
		pr_debug("%s: corkscrew_open() InternalConfig %8.8x.\n",
		       dev->name, config);
	}

	outw(TxReset, ioaddr + EL3_CMD);
	for (i = 20; i >= 0; i--)
		if (!(inw(ioaddr + EL3_STATUS) & CmdInProgress))
			break;

	outw(RxReset, ioaddr + EL3_CMD);
	/* Wait a few ticks for the RxReset command to complete. */
	for (i = 20; i >= 0; i--)
		if (!(inw(ioaddr + EL3_STATUS) & CmdInProgress))
			break;

	outw(SetStatusEnb | 0x00, ioaddr + EL3_CMD);

	/* Use the now-standard shared IRQ implementation. */
	if (vp->capabilities == 0x11c7) {
		/* Corkscrew: Cannot share ISA resources. */
		if (dev->irq == 0 ||
		    dev->dma == 0 ||
		    request_irq(dev->irq, corkscrew_interrupt, 0,
				vp->product_name, dev))
			return -EAGAIN;
		enable_dma(dev->dma);
		set_dma_mode(dev->dma, DMA_MODE_CASCADE);
	} else if (request_irq(dev->irq, corkscrew_interrupt, IRQF_SHARED,
			       vp->product_name, dev)) {
		return -EAGAIN;
	}

	if (corkscrew_debug > 1) {
		EL3WINDOW(4);
		pr_debug("%s: corkscrew_open() irq %d media status %4.4x.\n",
		       dev->name, dev->irq, inw(ioaddr + Wn4_Media));
	}

	/* Set the station address and mask in window 2 each time opened. */
	EL3WINDOW(2);
	for (i = 0; i < 6; i++)
		outb(dev->dev_addr[i], ioaddr + i);
	for (; i < 12; i += 2)
		outw(0, ioaddr + i);

	if (dev->if_port == 3)
		/* Start the thinnet transceiver. We should really wait 50ms... */
		outw(StartCoax, ioaddr + EL3_CMD);
	EL3WINDOW(4);
	outw((inw(ioaddr + Wn4_Media) & ~(Media_10TP | Media_SQE)) |
	     media_tbl[dev->if_port].media_bits, ioaddr + Wn4_Media);

	/* Switch to the stats window, and clear all stats by reading. */
	outw(StatsDisable, ioaddr + EL3_CMD);
	EL3WINDOW(6);
	for (i = 0; i < 10; i++)
		inb(ioaddr + i);
	inw(ioaddr + 10);
	inw(ioaddr + 12);
	/* New: On the Vortex we must also clear the BadSSD counter. */
	EL3WINDOW(4);
	inb(ioaddr + 12);
	/* ..and on the Boomerang we enable the extra statistics bits. */
	outw(0x0040, ioaddr + Wn4_NetDiag);

	/* Switch to register set 7 for normal use. */
	EL3WINDOW(7);

	if (vp->full_bus_master_rx) {	/* Boomerang bus master. */
		vp->cur_rx = vp->dirty_rx = 0;
		if (corkscrew_debug > 2)
			pr_debug("%s:  Filling in the Rx ring.\n", dev->name);
		for (i = 0; i < RX_RING_SIZE; i++) {
			struct sk_buff *skb;
			if (i < (RX_RING_SIZE - 1))
				vp->rx_ring[i].next =
				    isa_virt_to_bus(&vp->rx_ring[i + 1]);
			else
				vp->rx_ring[i].next = 0;
			vp->rx_ring[i].status = 0;	/* Clear complete bit. */
			vp->rx_ring[i].length = PKT_BUF_SZ | 0x80000000;
			skb = netdev_alloc_skb(dev, PKT_BUF_SZ);
			vp->rx_skbuff[i] = skb;
			if (skb == NULL)
				break;	/* Bad news!  */
			skb_reserve(skb, 2);	/* Align IP on 16 byte boundaries */
			vp->rx_ring[i].addr = isa_virt_to_bus(skb->data);
		}
		if (i != 0)
			vp->rx_ring[i - 1].next =
				isa_virt_to_bus(&vp->rx_ring[0]);	/* Wrap the ring. */
		outl(isa_virt_to_bus(&vp->rx_ring[0]), ioaddr + UpListPtr);
	}
	if (vp->full_bus_master_tx) {	/* Boomerang bus master Tx. */
		vp->cur_tx = vp->dirty_tx = 0;
		outb(PKT_BUF_SZ >> 8, ioaddr + TxFreeThreshold);	/* Room for a packet. */
		/* Clear the Tx ring. */
		for (i = 0; i < TX_RING_SIZE; i++)
			vp->tx_skbuff[i] = NULL;
		outl(0, ioaddr + DownListPtr);
	}
	/* Set receiver mode: presumably accept b-case and phys addr only. */
	set_rx_mode(dev);
	outw(StatsEnable, ioaddr + EL3_CMD);	/* Turn on statistics. */

	netif_start_queue(dev);

	outw(RxEnable, ioaddr + EL3_CMD);	/* Enable the receiver. */
	outw(TxEnable, ioaddr + EL3_CMD);	/* Enable transmitter. */
	/* Allow status bits to be seen. */
	outw(SetStatusEnb | AdapterFailure | IntReq | StatsFull |
	     (vp->full_bus_master_tx ? DownComplete : TxAvailable) |
	     (vp->full_bus_master_rx ? UpComplete : RxComplete) |
	     (vp->bus_master ? DMADone : 0), ioaddr + EL3_CMD);
	/* Ack all pending events, and set active indicator mask. */
	outw(AckIntr | IntLatch | TxAvailable | RxEarly | IntReq,
	     ioaddr + EL3_CMD);
	outw(SetIntrEnb | IntLatch | TxAvailable | RxComplete | StatsFull
	     | (vp->bus_master ? DMADone : 0) | UpComplete | DownComplete,
	     ioaddr + EL3_CMD);

	return 0;
}

static void corkscrew_timer(unsigned long data)
{
#ifdef AUTOMEDIA
	struct net_device *dev = (struct net_device *) data;
	struct corkscrew_private *vp = netdev_priv(dev);
	int ioaddr = dev->base_addr;
	unsigned long flags;
	int ok = 0;

	if (corkscrew_debug > 1)
		pr_debug("%s: Media selection timer tick happened, %s.\n",
		       dev->name, media_tbl[dev->if_port].name);

	spin_lock_irqsave(&vp->lock, flags);

	{
		int old_window = inw(ioaddr + EL3_CMD) >> 13;
		int media_status;
		EL3WINDOW(4);
		media_status = inw(ioaddr + Wn4_Media);
		switch (dev->if_port) {
		case 0:
		case 4:
		case 5:	/* 10baseT, 100baseTX, 100baseFX  */
			if (media_status & Media_LnkBeat) {
				ok = 1;
				if (corkscrew_debug > 1)
					pr_debug("%s: Media %s has link beat, %x.\n",
						dev->name,
						media_tbl[dev->if_port].name,
						media_status);
			} else if (corkscrew_debug > 1)
				pr_debug("%s: Media %s is has no link beat, %x.\n",
					dev->name,
					media_tbl[dev->if_port].name,
					media_status);

			break;
		default:	/* Other media types handled by Tx timeouts. */
			if (corkscrew_debug > 1)
				pr_debug("%s: Media %s is has no indication, %x.\n",
					dev->name,
					media_tbl[dev->if_port].name,
					media_status);
			ok = 1;
		}
		if (!ok) {
			__u32 config;

			do {
				dev->if_port =
				    media_tbl[dev->if_port].next;
			}
			while (!(vp->available_media & media_tbl[dev->if_port].mask));

			if (dev->if_port == 8) {	/* Go back to default. */
				dev->if_port = vp->default_media;
				if (corkscrew_debug > 1)
					pr_debug("%s: Media selection failing, using default %s port.\n",
						dev->name,
						media_tbl[dev->if_port].name);
			} else {
				if (corkscrew_debug > 1)
					pr_debug("%s: Media selection failed, now trying %s port.\n",
						dev->name,
						media_tbl[dev->if_port].name);
				vp->timer.expires = jiffies + media_tbl[dev->if_port].wait;
				add_timer(&vp->timer);
			}
			outw((media_status & ~(Media_10TP | Media_SQE)) |
			     media_tbl[dev->if_port].media_bits,
			     ioaddr + Wn4_Media);

			EL3WINDOW(3);
			config = inl(ioaddr + Wn3_Config);
			config = (config & ~Xcvr) | (dev->if_port << Xcvr_shift);
			outl(config, ioaddr + Wn3_Config);

			outw(dev->if_port == 3 ? StartCoax : StopCoax,
			     ioaddr + EL3_CMD);
		}
		EL3WINDOW(old_window);
	}

	spin_unlock_irqrestore(&vp->lock, flags);
	if (corkscrew_debug > 1)
		pr_debug("%s: Media selection timer finished, %s.\n",
		       dev->name, media_tbl[dev->if_port].name);

#endif				/* AUTOMEDIA */
}

static void corkscrew_timeout(struct net_device *dev)
{
	int i;
	struct corkscrew_private *vp = netdev_priv(dev);
	int ioaddr = dev->base_addr;

	pr_warning("%s: transmit timed out, tx_status %2.2x status %4.4x.\n",
	       dev->name, inb(ioaddr + TxStatus),
	       inw(ioaddr + EL3_STATUS));
	/* Slight code bloat to be user friendly. */
	if ((inb(ioaddr + TxStatus) & 0x88) == 0x88)
		pr_warning("%s: Transmitter encountered 16 collisions --"
		       " network cable problem?\n", dev->name);
#ifndef final_version
	pr_debug("  Flags; bus-master %d, full %d; dirty %d current %d.\n",
	       vp->full_bus_master_tx, vp->tx_full, vp->dirty_tx,
	       vp->cur_tx);
	pr_debug("  Down list %8.8x vs. %p.\n", inl(ioaddr + DownListPtr),
	       &vp->tx_ring[0]);
	for (i = 0; i < TX_RING_SIZE; i++) {
		pr_debug("  %d: %p  length %8.8x status %8.8x\n", i,
		       &vp->tx_ring[i],
		       vp->tx_ring[i].length, vp->tx_ring[i].status);
	}
#endif
	/* Issue TX_RESET and TX_START commands. */
	outw(TxReset, ioaddr + EL3_CMD);
	for (i = 20; i >= 0; i--)
		if (!(inw(ioaddr + EL3_STATUS) & CmdInProgress))
			break;
	outw(TxEnable, ioaddr + EL3_CMD);
	dev->trans_start = jiffies; /* prevent tx timeout */
	dev->stats.tx_errors++;
	dev->stats.tx_dropped++;
	netif_wake_queue(dev);
}

static netdev_tx_t corkscrew_start_xmit(struct sk_buff *skb,
					struct net_device *dev)
{
	struct corkscrew_private *vp = netdev_priv(dev);
	int ioaddr = dev->base_addr;

	/* Block a timer-based transmit from overlapping. */

	netif_stop_queue(dev);

	if (vp->full_bus_master_tx) {	/* BOOMERANG bus-master */
		/* Calculate the next Tx descriptor entry. */
		int entry = vp->cur_tx % TX_RING_SIZE;
		struct boom_tx_desc *prev_entry;
		unsigned long flags;
		int i;

		if (vp->tx_full)	/* No room to transmit with */
			return NETDEV_TX_BUSY;
		if (vp->cur_tx != 0)
			prev_entry = &vp->tx_ring[(vp->cur_tx - 1) % TX_RING_SIZE];
		else
			prev_entry = NULL;
		if (corkscrew_debug > 3)
			pr_debug("%s: Trying to send a packet, Tx index %d.\n",
				dev->name, vp->cur_tx);
		/* vp->tx_full = 1; */
		vp->tx_skbuff[entry] = skb;
		vp->tx_ring[entry].next = 0;
		vp->tx_ring[entry].addr = isa_virt_to_bus(skb->data);
		vp->tx_ring[entry].length = skb->len | 0x80000000;
		vp->tx_ring[entry].status = skb->len | 0x80000000;

		spin_lock_irqsave(&vp->lock, flags);
		outw(DownStall, ioaddr + EL3_CMD);
		/* Wait for the stall to complete. */
		for (i = 20; i >= 0; i--)
			if ((inw(ioaddr + EL3_STATUS) & CmdInProgress) == 0)
				break;
		if (prev_entry)
			prev_entry->next = isa_virt_to_bus(&vp->tx_ring[entry]);
		if (inl(ioaddr + DownListPtr) == 0) {
			outl(isa_virt_to_bus(&vp->tx_ring[entry]),
			     ioaddr + DownListPtr);
			queued_packet++;
		}
		outw(DownUnstall, ioaddr + EL3_CMD);
		spin_unlock_irqrestore(&vp->lock, flags);

		vp->cur_tx++;
		if (vp->cur_tx - vp->dirty_tx > TX_RING_SIZE - 1)
			vp->tx_full = 1;
		else {		/* Clear previous interrupt enable. */
			if (prev_entry)
				prev_entry->status &= ~0x80000000;
			netif_wake_queue(dev);
		}
		return NETDEV_TX_OK;
	}
	/* Put out the doubleword header... */
	outl(skb->len, ioaddr + TX_FIFO);
	dev->stats.tx_bytes += skb->len;
#ifdef VORTEX_BUS_MASTER
	if (vp->bus_master) {
		/* Set the bus-master controller to transfer the packet. */
		outl((int) (skb->data), ioaddr + Wn7_MasterAddr);
		outw((skb->len + 3) & ~3, ioaddr + Wn7_MasterLen);
		vp->tx_skb = skb;
		outw(StartDMADown, ioaddr + EL3_CMD);
		/* queue will be woken at the DMADone interrupt. */
	} else {
		/* ... and the packet rounded to a doubleword. */
		outsl(ioaddr + TX_FIFO, skb->data, (skb->len + 3) >> 2);
		dev_kfree_skb(skb);
		if (inw(ioaddr + TxFree) > 1536) {
			netif_wake_queue(dev);
		} else
			/* Interrupt us when the FIFO has room for max-sized packet. */
			outw(SetTxThreshold + (1536 >> 2),
			     ioaddr + EL3_CMD);
	}
#else
	/* ... and the packet rounded to a doubleword. */
	outsl(ioaddr + TX_FIFO, skb->data, (skb->len + 3) >> 2);
	dev_kfree_skb(skb);
	if (inw(ioaddr + TxFree) > 1536) {
		netif_wake_queue(dev);
	} else
		/* Interrupt us when the FIFO has room for max-sized packet. */
		outw(SetTxThreshold + (1536 >> 2), ioaddr + EL3_CMD);
#endif				/* bus master */


	/* Clear the Tx status stack. */
	{
		short tx_status;
		int i = 4;

		while (--i > 0 && (tx_status = inb(ioaddr + TxStatus)) > 0) {
			if (tx_status & 0x3C) {	/* A Tx-disabling error occurred.  */
				if (corkscrew_debug > 2)
					pr_debug("%s: Tx error, status %2.2x.\n",
						dev->name, tx_status);
				if (tx_status & 0x04)
					dev->stats.tx_fifo_errors++;
				if (tx_status & 0x38)
					dev->stats.tx_aborted_errors++;
				if (tx_status & 0x30) {
					int j;
					outw(TxReset, ioaddr + EL3_CMD);
					for (j = 20; j >= 0; j--)
						if (!(inw(ioaddr + EL3_STATUS) & CmdInProgress))
							break;
				}
				outw(TxEnable, ioaddr + EL3_CMD);
			}
			outb(0x00, ioaddr + TxStatus);	/* Pop the status stack. */
		}
	}
	return NETDEV_TX_OK;
}

/* The interrupt handler does all of the Rx thread work and cleans up
   after the Tx thread. */

static irqreturn_t corkscrew_interrupt(int irq, void *dev_id)
{
	/* Use the now-standard shared IRQ implementation. */
	struct net_device *dev = dev_id;
	struct corkscrew_private *lp = netdev_priv(dev);
	int ioaddr, status;
	int latency;
	int i = max_interrupt_work;

	ioaddr = dev->base_addr;
	latency = inb(ioaddr + Timer);

	spin_lock(&lp->lock);

	status = inw(ioaddr + EL3_STATUS);

	if (corkscrew_debug > 4)
		pr_debug("%s: interrupt, status %4.4x, timer %d.\n",
			dev->name, status, latency);
	if ((status & 0xE000) != 0xE000) {
		static int donedidthis;
		/* Some interrupt controllers store a bogus interrupt from boot-time.
		   Ignore a single early interrupt, but don't hang the machine for
		   other interrupt problems. */
		if (donedidthis++ > 100) {
			pr_err("%s: Bogus interrupt, bailing. Status %4.4x, start=%d.\n",
				   dev->name, status, netif_running(dev));
			free_irq(dev->irq, dev);
			dev->irq = -1;
		}
	}

	do {
		if (corkscrew_debug > 5)
			pr_debug("%s: In interrupt loop, status %4.4x.\n",
			       dev->name, status);
		if (status & RxComplete)
			corkscrew_rx(dev);

		if (status & TxAvailable) {
			if (corkscrew_debug > 5)
				pr_debug("	TX room bit was handled.\n");
			/* There's room in the FIFO for a full-sized packet. */
			outw(AckIntr | TxAvailable, ioaddr + EL3_CMD);
			netif_wake_queue(dev);
		}
		if (status & DownComplete) {
			unsigned int dirty_tx = lp->dirty_tx;

			while (lp->cur_tx - dirty_tx > 0) {
				int entry = dirty_tx % TX_RING_SIZE;
				if (inl(ioaddr + DownListPtr) == isa_virt_to_bus(&lp->tx_ring[entry]))
					break;	/* It still hasn't been processed. */
				if (lp->tx_skbuff[entry]) {
					dev_kfree_skb_irq(lp->tx_skbuff[entry]);
					lp->tx_skbuff[entry] = NULL;
				}
				dirty_tx++;
			}
			lp->dirty_tx = dirty_tx;
			outw(AckIntr | DownComplete, ioaddr + EL3_CMD);
			if (lp->tx_full && (lp->cur_tx - dirty_tx <= TX_RING_SIZE - 1)) {
				lp->tx_full = 0;
				netif_wake_queue(dev);
			}
		}
#ifdef VORTEX_BUS_MASTER
		if (status & DMADone) {
			outw(0x1000, ioaddr + Wn7_MasterStatus);	/* Ack the event. */
			dev_kfree_skb_irq(lp->tx_skb);	/* Release the transferred buffer */
			netif_wake_queue(dev);
		}
#endif
		if (status & UpComplete) {
			boomerang_rx(dev);
			outw(AckIntr | UpComplete, ioaddr + EL3_CMD);
		}
		if (status & (AdapterFailure | RxEarly | StatsFull)) {
			/* Handle all uncommon interrupts at once. */
			if (status & RxEarly) {	/* Rx early is unused. */
				corkscrew_rx(dev);
				outw(AckIntr | RxEarly, ioaddr + EL3_CMD);
			}
			if (status & StatsFull) {	/* Empty statistics. */
				static int DoneDidThat;
				if (corkscrew_debug > 4)
					pr_debug("%s: Updating stats.\n", dev->name);
				update_stats(ioaddr, dev);
				/* DEBUG HACK: Disable statistics as an interrupt source. */
				/* This occurs when we have the wrong media type! */
				if (DoneDidThat == 0 && inw(ioaddr + EL3_STATUS) & StatsFull) {
					int win, reg;
					pr_notice("%s: Updating stats failed, disabling stats as an interrupt source.\n",
						dev->name);
					for (win = 0; win < 8; win++) {
						EL3WINDOW(win);
						pr_notice("Vortex window %d:", win);
						for (reg = 0; reg < 16; reg++)
							pr_cont(" %2.2x", inb(ioaddr + reg));
						pr_cont("\n");
					}
					EL3WINDOW(7);
					outw(SetIntrEnb | TxAvailable |
					     RxComplete | AdapterFailure |
					     UpComplete | DownComplete |
					     TxComplete, ioaddr + EL3_CMD);
					DoneDidThat++;
				}
			}
			if (status & AdapterFailure) {
				/* Adapter failure requires Rx reset and reinit. */
				outw(RxReset, ioaddr + EL3_CMD);
				/* Set the Rx filter to the current state. */
				set_rx_mode(dev);
				outw(RxEnable, ioaddr + EL3_CMD);	/* Re-enable the receiver. */
				outw(AckIntr | AdapterFailure,
				     ioaddr + EL3_CMD);
			}
		}

		if (--i < 0) {
			pr_err("%s: Too much work in interrupt, status %4.4x. Disabling functions (%4.4x).\n",
				dev->name, status, SetStatusEnb | ((~status) & 0x7FE));
			/* Disable all pending interrupts. */
			outw(SetStatusEnb | ((~status) & 0x7FE), ioaddr + EL3_CMD);
			outw(AckIntr | 0x7FF, ioaddr + EL3_CMD);
			break;
		}
		/* Acknowledge the IRQ. */
		outw(AckIntr | IntReq | IntLatch, ioaddr + EL3_CMD);

	} while ((status = inw(ioaddr + EL3_STATUS)) & (IntLatch | RxComplete));

	spin_unlock(&lp->lock);

	if (corkscrew_debug > 4)
		pr_debug("%s: exiting interrupt, status %4.4x.\n", dev->name, status);
	return IRQ_HANDLED;
}

static int corkscrew_rx(struct net_device *dev)
{
	int ioaddr = dev->base_addr;
	int i;
	short rx_status;

	if (corkscrew_debug > 5)
		pr_debug("   In rx_packet(), status %4.4x, rx_status %4.4x.\n",
		     inw(ioaddr + EL3_STATUS), inw(ioaddr + RxStatus));
	while ((rx_status = inw(ioaddr + RxStatus)) > 0) {
		if (rx_status & 0x4000) {	/* Error, update stats. */
			unsigned char rx_error = inb(ioaddr + RxErrors);
			if (corkscrew_debug > 2)
				pr_debug(" Rx error: status %2.2x.\n",
				       rx_error);
			dev->stats.rx_errors++;
			if (rx_error & 0x01)
				dev->stats.rx_over_errors++;
			if (rx_error & 0x02)
				dev->stats.rx_length_errors++;
			if (rx_error & 0x04)
				dev->stats.rx_frame_errors++;
			if (rx_error & 0x08)
				dev->stats.rx_crc_errors++;
			if (rx_error & 0x10)
				dev->stats.rx_length_errors++;
		} else {
			/* The packet length: up to 4.5K!. */
			short pkt_len = rx_status & 0x1fff;
			struct sk_buff *skb;

			skb = netdev_alloc_skb(dev, pkt_len + 5 + 2);
			if (corkscrew_debug > 4)
				pr_debug("Receiving packet size %d status %4.4x.\n",
				     pkt_len, rx_status);
			if (skb != NULL) {
				skb_reserve(skb, 2);	/* Align IP on 16 byte boundaries */
				/* 'skb_put()' points to the start of sk_buff data area. */
				insl(ioaddr + RX_FIFO,
				     skb_put(skb, pkt_len),
				     (pkt_len + 3) >> 2);
				outw(RxDiscard, ioaddr + EL3_CMD);	/* Pop top Rx packet. */
				skb->protocol = eth_type_trans(skb, dev);
				netif_rx(skb);
				dev->stats.rx_packets++;
				dev->stats.rx_bytes += pkt_len;
				/* Wait a limited time to go to next packet. */
				for (i = 200; i >= 0; i--)
					if (! (inw(ioaddr + EL3_STATUS) & CmdInProgress))
						break;
				continue;
			} else if (corkscrew_debug)
				pr_debug("%s: Couldn't allocate a sk_buff of size %d.\n", dev->name, pkt_len);
		}
		outw(RxDiscard, ioaddr + EL3_CMD);
		dev->stats.rx_dropped++;
		/* Wait a limited time to skip this packet. */
		for (i = 200; i >= 0; i--)
			if (!(inw(ioaddr + EL3_STATUS) & CmdInProgress))
				break;
	}
	return 0;
}

static int boomerang_rx(struct net_device *dev)
{
	struct corkscrew_private *vp = netdev_priv(dev);
	int entry = vp->cur_rx % RX_RING_SIZE;
	int ioaddr = dev->base_addr;
	int rx_status;

	if (corkscrew_debug > 5)
		pr_debug("   In boomerang_rx(), status %4.4x, rx_status %4.4x.\n",
			inw(ioaddr + EL3_STATUS), inw(ioaddr + RxStatus));
	while ((rx_status = vp->rx_ring[entry].status) & RxDComplete) {
		if (rx_status & RxDError) {	/* Error, update stats. */
			unsigned char rx_error = rx_status >> 16;
			if (corkscrew_debug > 2)
				pr_debug(" Rx error: status %2.2x.\n",
				       rx_error);
			dev->stats.rx_errors++;
			if (rx_error & 0x01)
				dev->stats.rx_over_errors++;
			if (rx_error & 0x02)
				dev->stats.rx_length_errors++;
			if (rx_error & 0x04)
				dev->stats.rx_frame_errors++;
			if (rx_error & 0x08)
				dev->stats.rx_crc_errors++;
			if (rx_error & 0x10)
				dev->stats.rx_length_errors++;
		} else {
			/* The packet length: up to 4.5K!. */
			short pkt_len = rx_status & 0x1fff;
			struct sk_buff *skb;

			dev->stats.rx_bytes += pkt_len;
			if (corkscrew_debug > 4)
				pr_debug("Receiving packet size %d status %4.4x.\n",
				     pkt_len, rx_status);

			/* Check if the packet is long enough to just accept without
			   copying to a properly sized skbuff. */
			if (pkt_len < rx_copybreak &&
			    (skb = netdev_alloc_skb(dev, pkt_len + 4)) != NULL) {
				skb_reserve(skb, 2);	/* Align IP on 16 byte boundaries */
				/* 'skb_put()' points to the start of sk_buff data area. */
				memcpy(skb_put(skb, pkt_len),
				       isa_bus_to_virt(vp->rx_ring[entry].
						   addr), pkt_len);
				rx_copy++;
			} else {
				void *temp;
				/* Pass up the skbuff already on the Rx ring. */
				skb = vp->rx_skbuff[entry];
				vp->rx_skbuff[entry] = NULL;
				temp = skb_put(skb, pkt_len);
				/* Remove this checking code for final release. */
				if (isa_bus_to_virt(vp->rx_ring[entry].addr) != temp)
					pr_warning("%s: Warning -- the skbuff addresses do not match"
					     " in boomerang_rx: %p vs. %p / %p.\n",
					     dev->name,
					     isa_bus_to_virt(vp->
							 rx_ring[entry].
							 addr), skb->head,
					     temp);
				rx_nocopy++;
			}
			skb->protocol = eth_type_trans(skb, dev);
			netif_rx(skb);
			dev->stats.rx_packets++;
		}
		entry = (++vp->cur_rx) % RX_RING_SIZE;
	}
	/* Refill the Rx ring buffers. */
	for (; vp->cur_rx - vp->dirty_rx > 0; vp->dirty_rx++) {
		struct sk_buff *skb;
		entry = vp->dirty_rx % RX_RING_SIZE;
		if (vp->rx_skbuff[entry] == NULL) {
			skb = netdev_alloc_skb(dev, PKT_BUF_SZ);
			if (skb == NULL)
				break;	/* Bad news!  */
			skb_reserve(skb, 2);	/* Align IP on 16 byte boundaries */
			vp->rx_ring[entry].addr = isa_virt_to_bus(skb->data);
			vp->rx_skbuff[entry] = skb;
		}
		vp->rx_ring[entry].status = 0;	/* Clear complete bit. */
	}
	return 0;
}

static int corkscrew_close(struct net_device *dev)
{
	struct corkscrew_private *vp = netdev_priv(dev);
	int ioaddr = dev->base_addr;
	int i;

	netif_stop_queue(dev);

	if (corkscrew_debug > 1) {
		pr_debug("%s: corkscrew_close() status %4.4x, Tx status %2.2x.\n",
		     dev->name, inw(ioaddr + EL3_STATUS),
		     inb(ioaddr + TxStatus));
		pr_debug("%s: corkscrew close stats: rx_nocopy %d rx_copy %d tx_queued %d.\n",
			dev->name, rx_nocopy, rx_copy, queued_packet);
	}

	del_timer(&vp->timer);

	/* Turn off statistics ASAP.  We update lp->stats below. */
	outw(StatsDisable, ioaddr + EL3_CMD);

	/* Disable the receiver and transmitter. */
	outw(RxDisable, ioaddr + EL3_CMD);
	outw(TxDisable, ioaddr + EL3_CMD);

	if (dev->if_port == XCVR_10base2)
		/* Turn off thinnet power.  Green! */
		outw(StopCoax, ioaddr + EL3_CMD);

	free_irq(dev->irq, dev);

	outw(SetIntrEnb | 0x0000, ioaddr + EL3_CMD);

	update_stats(ioaddr, dev);
	if (vp->full_bus_master_rx) {	/* Free Boomerang bus master Rx buffers. */
		outl(0, ioaddr + UpListPtr);
		for (i = 0; i < RX_RING_SIZE; i++)
			if (vp->rx_skbuff[i]) {
				dev_kfree_skb(vp->rx_skbuff[i]);
				vp->rx_skbuff[i] = NULL;
			}
	}
	if (vp->full_bus_master_tx) {	/* Free Boomerang bus master Tx buffers. */
		outl(0, ioaddr + DownListPtr);
		for (i = 0; i < TX_RING_SIZE; i++)
			if (vp->tx_skbuff[i]) {
				dev_kfree_skb(vp->tx_skbuff[i]);
				vp->tx_skbuff[i] = NULL;
			}
	}

	return 0;
}

static struct net_device_stats *corkscrew_get_stats(struct net_device *dev)
{
	struct corkscrew_private *vp = netdev_priv(dev);
	unsigned long flags;

	if (netif_running(dev)) {
		spin_lock_irqsave(&vp->lock, flags);
		update_stats(dev->base_addr, dev);
		spin_unlock_irqrestore(&vp->lock, flags);
	}
	return &dev->stats;
}

/*  Update statistics.
	Unlike with the EL3 we need not worry about interrupts changing
	the window setting from underneath us, but we must still guard
	against a race condition with a StatsUpdate interrupt updating the
	table.  This is done by checking that the ASM (!) code generated uses
	atomic updates with '+='.
	*/
static void update_stats(int ioaddr, struct net_device *dev)
{
	/* Unlike the 3c5x9 we need not turn off stats updates while reading. */
	/* Switch to the stats window, and read everything. */
	EL3WINDOW(6);
	dev->stats.tx_carrier_errors += inb(ioaddr + 0);
	dev->stats.tx_heartbeat_errors += inb(ioaddr + 1);
	/* Multiple collisions. */ inb(ioaddr + 2);
	dev->stats.collisions += inb(ioaddr + 3);
	dev->stats.tx_window_errors += inb(ioaddr + 4);
	dev->stats.rx_fifo_errors += inb(ioaddr + 5);
	dev->stats.tx_packets += inb(ioaddr + 6);
	dev->stats.tx_packets += (inb(ioaddr + 9) & 0x30) << 4;
						/* Rx packets   */ inb(ioaddr + 7);
						/* Must read to clear */
	/* Tx deferrals */ inb(ioaddr + 8);
	/* Don't bother with register 9, an extension of registers 6&7.
	   If we do use the 6&7 values the atomic update assumption above
	   is invalid. */
	inw(ioaddr + 10);	/* Total Rx and Tx octets. */
	inw(ioaddr + 12);
	/* New: On the Vortex we must also clear the BadSSD counter. */
	EL3WINDOW(4);
	inb(ioaddr + 12);

	/* We change back to window 7 (not 1) with the Vortex. */
	EL3WINDOW(7);
}

/* This new version of set_rx_mode() supports v1.4 kernels.
   The Vortex chip has no documented multicast filter, so the only
   multicast setting is to receive all multicast frames.  At least
   the chip has a very clean way to set the mode, unlike many others. */
static void set_rx_mode(struct net_device *dev)
{
	int ioaddr = dev->base_addr;
	short new_mode;

	if (dev->flags & IFF_PROMISC) {
		if (corkscrew_debug > 3)
			pr_debug("%s: Setting promiscuous mode.\n",
			       dev->name);
		new_mode = SetRxFilter | RxStation | RxMulticast | RxBroadcast | RxProm;
	} else if (!netdev_mc_empty(dev) || dev->flags & IFF_ALLMULTI) {
		new_mode = SetRxFilter | RxStation | RxMulticast | RxBroadcast;
	} else
		new_mode = SetRxFilter | RxStation | RxBroadcast;

	outw(new_mode, ioaddr + EL3_CMD);
}

static void netdev_get_drvinfo(struct net_device *dev,
			       struct ethtool_drvinfo *info)
{
	strlcpy(info->driver, DRV_NAME, sizeof(info->driver));
	strlcpy(info->version, DRV_VERSION, sizeof(info->version));
	snprintf(info->bus_info, sizeof(info->bus_info), "ISA 0x%lx",
		 dev->base_addr);
}

static u32 netdev_get_msglevel(struct net_device *dev)
{
	return corkscrew_debug;
}

static void netdev_set_msglevel(struct net_device *dev, u32 level)
{
	corkscrew_debug = level;
}

static const struct ethtool_ops netdev_ethtool_ops = {
	.get_drvinfo		= netdev_get_drvinfo,
	.get_msglevel		= netdev_get_msglevel,
	.set_msglevel		= netdev_set_msglevel,
};


#ifdef MODULE
void cleanup_module(void)
{
	while (!list_empty(&root_corkscrew_dev)) {
		struct net_device *dev;
		struct corkscrew_private *vp;

		vp = list_entry(root_corkscrew_dev.next,
				struct corkscrew_private, list);
		dev = vp->our_dev;
		unregister_netdev(dev);
		cleanup_card(dev);
		free_netdev(dev);
	}
}
#endif				/* MODULE */