aboutsummaryrefslogtreecommitdiff
path: root/drivers/net/ethernet/toshiba/spider_net.c
blob: 23417266b7ecc24aca2a0e562cd17985399c9cc3 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
1043
1044
1045
1046
1047
1048
1049
1050
1051
1052
1053
1054
1055
1056
1057
1058
1059
1060
1061
1062
1063
1064
1065
1066
1067
1068
1069
1070
1071
1072
1073
1074
1075
1076
1077
1078
1079
1080
1081
1082
1083
1084
1085
1086
1087
1088
1089
1090
1091
1092
1093
1094
1095
1096
1097
1098
1099
1100
1101
1102
1103
1104
1105
1106
1107
1108
1109
1110
1111
1112
1113
1114
1115
1116
1117
1118
1119
1120
1121
1122
1123
1124
1125
1126
1127
1128
1129
1130
1131
1132
1133
1134
1135
1136
1137
1138
1139
1140
1141
1142
1143
1144
1145
1146
1147
1148
1149
1150
1151
1152
1153
1154
1155
1156
1157
1158
1159
1160
1161
1162
1163
1164
1165
1166
1167
1168
1169
1170
1171
1172
1173
1174
1175
1176
1177
1178
1179
1180
1181
1182
1183
1184
1185
1186
1187
1188
1189
1190
1191
1192
1193
1194
1195
1196
1197
1198
1199
1200
1201
1202
1203
1204
1205
1206
1207
1208
1209
1210
1211
1212
1213
1214
1215
1216
1217
1218
1219
1220
1221
1222
1223
1224
1225
1226
1227
1228
1229
1230
1231
1232
1233
1234
1235
1236
1237
1238
1239
1240
1241
1242
1243
1244
1245
1246
1247
1248
1249
1250
1251
1252
1253
1254
1255
1256
1257
1258
1259
1260
1261
1262
1263
1264
1265
1266
1267
1268
1269
1270
1271
1272
1273
1274
1275
1276
1277
1278
1279
1280
1281
1282
1283
1284
1285
1286
1287
1288
1289
1290
1291
1292
1293
1294
1295
1296
1297
1298
1299
1300
1301
1302
1303
1304
1305
1306
1307
1308
1309
1310
1311
1312
1313
1314
1315
1316
1317
1318
1319
1320
1321
1322
1323
1324
1325
1326
1327
1328
1329
1330
1331
1332
1333
1334
1335
1336
1337
1338
1339
1340
1341
1342
1343
1344
1345
1346
1347
1348
1349
1350
1351
1352
1353
1354
1355
1356
1357
1358
1359
1360
1361
1362
1363
1364
1365
1366
1367
1368
1369
1370
1371
1372
1373
1374
1375
1376
1377
1378
1379
1380
1381
1382
1383
1384
1385
1386
1387
1388
1389
1390
1391
1392
1393
1394
1395
1396
1397
1398
1399
1400
1401
1402
1403
1404
1405
1406
1407
1408
1409
1410
1411
1412
1413
1414
1415
1416
1417
1418
1419
1420
1421
1422
1423
1424
1425
1426
1427
1428
1429
1430
1431
1432
1433
1434
1435
1436
1437
1438
1439
1440
1441
1442
1443
1444
1445
1446
1447
1448
1449
1450
1451
1452
1453
1454
1455
1456
1457
1458
1459
1460
1461
1462
1463
1464
1465
1466
1467
1468
1469
1470
1471
1472
1473
1474
1475
1476
1477
1478
1479
1480
1481
1482
1483
1484
1485
1486
1487
1488
1489
1490
1491
1492
1493
1494
1495
1496
1497
1498
1499
1500
1501
1502
1503
1504
1505
1506
1507
1508
1509
1510
1511
1512
1513
1514
1515
1516
1517
1518
1519
1520
1521
1522
1523
1524
1525
1526
1527
1528
1529
1530
1531
1532
1533
1534
1535
1536
1537
1538
1539
1540
1541
1542
1543
1544
1545
1546
1547
1548
1549
1550
1551
1552
1553
1554
1555
1556
1557
1558
1559
1560
1561
1562
1563
1564
1565
1566
1567
1568
1569
1570
1571
1572
1573
1574
1575
1576
1577
1578
1579
1580
1581
1582
1583
1584
1585
1586
1587
1588
1589
1590
1591
1592
1593
1594
1595
1596
1597
1598
1599
1600
1601
1602
1603
1604
1605
1606
1607
1608
1609
1610
1611
1612
1613
1614
1615
1616
1617
1618
1619
1620
1621
1622
1623
1624
1625
1626
1627
1628
1629
1630
1631
1632
1633
1634
1635
1636
1637
1638
1639
1640
1641
1642
1643
1644
1645
1646
1647
1648
1649
1650
1651
1652
1653
1654
1655
1656
1657
1658
1659
1660
1661
1662
1663
1664
1665
1666
1667
1668
1669
1670
1671
1672
1673
1674
1675
1676
1677
1678
1679
1680
1681
1682
1683
1684
1685
1686
1687
1688
1689
1690
1691
1692
1693
1694
1695
1696
1697
1698
1699
1700
1701
1702
1703
1704
1705
1706
1707
1708
1709
1710
1711
1712
1713
1714
1715
1716
1717
1718
1719
1720
1721
1722
1723
1724
1725
1726
1727
1728
1729
1730
1731
1732
1733
1734
1735
1736
1737
1738
1739
1740
1741
1742
1743
1744
1745
1746
1747
1748
1749
1750
1751
1752
1753
1754
1755
1756
1757
1758
1759
1760
1761
1762
1763
1764
1765
1766
1767
1768
1769
1770
1771
1772
1773
1774
1775
1776
1777
1778
1779
1780
1781
1782
1783
1784
1785
1786
1787
1788
1789
1790
1791
1792
1793
1794
1795
1796
1797
1798
1799
1800
1801
1802
1803
1804
1805
1806
1807
1808
1809
1810
1811
1812
1813
1814
1815
1816
1817
1818
1819
1820
1821
1822
1823
1824
1825
1826
1827
1828
1829
1830
1831
1832
1833
1834
1835
1836
1837
1838
1839
1840
1841
1842
1843
1844
1845
1846
1847
1848
1849
1850
1851
1852
1853
1854
1855
1856
1857
1858
1859
1860
1861
1862
1863
1864
1865
1866
1867
1868
1869
1870
1871
1872
1873
1874
1875
1876
1877
1878
1879
1880
1881
1882
1883
1884
1885
1886
1887
1888
1889
1890
1891
1892
1893
1894
1895
1896
1897
1898
1899
1900
1901
1902
1903
1904
1905
1906
1907
1908
1909
1910
1911
1912
1913
1914
1915
1916
1917
1918
1919
1920
1921
1922
1923
1924
1925
1926
1927
1928
1929
1930
1931
1932
1933
1934
1935
1936
1937
1938
1939
1940
1941
1942
1943
1944
1945
1946
1947
1948
1949
1950
1951
1952
1953
1954
1955
1956
1957
1958
1959
1960
1961
1962
1963
1964
1965
1966
1967
1968
1969
1970
1971
1972
1973
1974
1975
1976
1977
1978
1979
1980
1981
1982
1983
1984
1985
1986
1987
1988
1989
1990
1991
1992
1993
1994
1995
1996
1997
1998
1999
2000
2001
2002
2003
2004
2005
2006
2007
2008
2009
2010
2011
2012
2013
2014
2015
2016
2017
2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
2028
2029
2030
2031
2032
2033
2034
2035
2036
2037
2038
2039
2040
2041
2042
2043
2044
2045
2046
2047
2048
2049
2050
2051
2052
2053
2054
2055
2056
2057
2058
2059
2060
2061
2062
2063
2064
2065
2066
2067
2068
2069
2070
2071
2072
2073
2074
2075
2076
2077
2078
2079
2080
2081
2082
2083
2084
2085
2086
2087
2088
2089
2090
2091
2092
2093
2094
2095
2096
2097
2098
2099
2100
2101
2102
2103
2104
2105
2106
2107
2108
2109
2110
2111
2112
2113
2114
2115
2116
2117
2118
2119
2120
2121
2122
2123
2124
2125
2126
2127
2128
2129
2130
2131
2132
2133
2134
2135
2136
2137
2138
2139
2140
2141
2142
2143
2144
2145
2146
2147
2148
2149
2150
2151
2152
2153
2154
2155
2156
2157
2158
2159
2160
2161
2162
2163
2164
2165
2166
2167
2168
2169
2170
2171
2172
2173
2174
2175
2176
2177
2178
2179
2180
2181
2182
2183
2184
2185
2186
2187
2188
2189
2190
2191
2192
2193
2194
2195
2196
2197
2198
2199
2200
2201
2202
2203
2204
2205
2206
2207
2208
2209
2210
2211
2212
2213
2214
2215
2216
2217
2218
2219
2220
2221
2222
2223
2224
2225
2226
2227
2228
2229
2230
2231
2232
2233
2234
2235
2236
2237
2238
2239
2240
2241
2242
2243
2244
2245
2246
2247
2248
2249
2250
2251
2252
2253
2254
2255
2256
2257
2258
2259
2260
2261
2262
2263
2264
2265
2266
2267
2268
2269
2270
2271
2272
2273
2274
2275
2276
2277
2278
2279
2280
2281
2282
2283
2284
2285
2286
2287
2288
2289
2290
2291
2292
2293
2294
2295
2296
2297
2298
2299
2300
2301
2302
2303
2304
2305
2306
2307
2308
2309
2310
2311
2312
2313
2314
2315
2316
2317
2318
2319
2320
2321
2322
2323
2324
2325
2326
2327
2328
2329
2330
2331
2332
2333
2334
2335
2336
2337
2338
2339
2340
2341
2342
2343
2344
2345
2346
2347
2348
2349
2350
2351
2352
2353
2354
2355
2356
2357
2358
2359
2360
2361
2362
2363
2364
2365
2366
2367
2368
2369
2370
2371
2372
2373
2374
2375
2376
2377
2378
2379
2380
2381
2382
2383
2384
2385
2386
2387
2388
2389
2390
2391
2392
2393
2394
2395
2396
2397
2398
2399
2400
2401
2402
2403
2404
2405
2406
2407
2408
2409
2410
2411
2412
2413
2414
2415
2416
2417
2418
2419
2420
2421
2422
2423
2424
2425
2426
2427
2428
2429
2430
2431
2432
2433
2434
2435
2436
2437
2438
2439
2440
2441
2442
2443
2444
2445
2446
2447
2448
2449
2450
2451
2452
2453
2454
2455
2456
2457
2458
2459
2460
2461
2462
2463
2464
2465
2466
2467
2468
2469
2470
2471
2472
2473
2474
2475
2476
2477
2478
2479
2480
2481
2482
2483
2484
2485
2486
2487
2488
2489
2490
2491
2492
2493
2494
2495
2496
2497
2498
2499
2500
2501
2502
2503
2504
2505
2506
2507
2508
2509
2510
2511
2512
2513
2514
2515
2516
2517
2518
2519
2520
2521
2522
2523
2524
2525
2526
2527
2528
2529
2530
2531
2532
2533
2534
2535
2536
2537
2538
2539
2540
2541
2542
2543
2544
2545
2546
2547
2548
2549
2550
/*
 * Network device driver for Cell Processor-Based Blade and Celleb platform
 *
 * (C) Copyright IBM Corp. 2005
 * (C) Copyright 2006 TOSHIBA CORPORATION
 *
 * Authors : Utz Bacher <utz.bacher@de.ibm.com>
 *           Jens Osterkamp <Jens.Osterkamp@de.ibm.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, or (at your option)
 * any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 */

#include <linux/compiler.h>
#include <linux/crc32.h>
#include <linux/delay.h>
#include <linux/etherdevice.h>
#include <linux/ethtool.h>
#include <linux/firmware.h>
#include <linux/if_vlan.h>
#include <linux/in.h>
#include <linux/init.h>
#include <linux/interrupt.h>
#include <linux/gfp.h>
#include <linux/ioport.h>
#include <linux/ip.h>
#include <linux/kernel.h>
#include <linux/mii.h>
#include <linux/module.h>
#include <linux/netdevice.h>
#include <linux/device.h>
#include <linux/pci.h>
#include <linux/skbuff.h>
#include <linux/tcp.h>
#include <linux/types.h>
#include <linux/vmalloc.h>
#include <linux/wait.h>
#include <linux/workqueue.h>
#include <linux/bitops.h>
#include <net/checksum.h>

#include "spider_net.h"

MODULE_AUTHOR("Utz Bacher <utz.bacher@de.ibm.com> and Jens Osterkamp " \
	      "<Jens.Osterkamp@de.ibm.com>");
MODULE_DESCRIPTION("Spider Southbridge Gigabit Ethernet driver");
MODULE_LICENSE("GPL");
MODULE_VERSION(VERSION);
MODULE_FIRMWARE(SPIDER_NET_FIRMWARE_NAME);

static int rx_descriptors = SPIDER_NET_RX_DESCRIPTORS_DEFAULT;
static int tx_descriptors = SPIDER_NET_TX_DESCRIPTORS_DEFAULT;

module_param(rx_descriptors, int, 0444);
module_param(tx_descriptors, int, 0444);

MODULE_PARM_DESC(rx_descriptors, "number of descriptors used " \
		 "in rx chains");
MODULE_PARM_DESC(tx_descriptors, "number of descriptors used " \
		 "in tx chain");

char spider_net_driver_name[] = "spidernet";

static const struct pci_device_id spider_net_pci_tbl[] = {
	{ PCI_VENDOR_ID_TOSHIBA_2, PCI_DEVICE_ID_TOSHIBA_SPIDER_NET,
	  PCI_ANY_ID, PCI_ANY_ID, 0, 0, 0UL },
	{ 0, }
};

MODULE_DEVICE_TABLE(pci, spider_net_pci_tbl);

/**
 * spider_net_read_reg - reads an SMMIO register of a card
 * @card: device structure
 * @reg: register to read from
 *
 * returns the content of the specified SMMIO register.
 */
static inline u32
spider_net_read_reg(struct spider_net_card *card, u32 reg)
{
	/* We use the powerpc specific variants instead of readl_be() because
	 * we know spidernet is not a real PCI device and we can thus avoid the
	 * performance hit caused by the PCI workarounds.
	 */
	return in_be32(card->regs + reg);
}

/**
 * spider_net_write_reg - writes to an SMMIO register of a card
 * @card: device structure
 * @reg: register to write to
 * @value: value to write into the specified SMMIO register
 */
static inline void
spider_net_write_reg(struct spider_net_card *card, u32 reg, u32 value)
{
	/* We use the powerpc specific variants instead of writel_be() because
	 * we know spidernet is not a real PCI device and we can thus avoid the
	 * performance hit caused by the PCI workarounds.
	 */
	out_be32(card->regs + reg, value);
}

/**
 * spider_net_write_phy - write to phy register
 * @netdev: adapter to be written to
 * @mii_id: id of MII
 * @reg: PHY register
 * @val: value to be written to phy register
 *
 * spider_net_write_phy_register writes to an arbitrary PHY
 * register via the spider GPCWOPCMD register. We assume the queue does
 * not run full (not more than 15 commands outstanding).
 **/
static void
spider_net_write_phy(struct net_device *netdev, int mii_id,
		     int reg, int val)
{
	struct spider_net_card *card = netdev_priv(netdev);
	u32 writevalue;

	writevalue = ((u32)mii_id << 21) |
		((u32)reg << 16) | ((u32)val);

	spider_net_write_reg(card, SPIDER_NET_GPCWOPCMD, writevalue);
}

/**
 * spider_net_read_phy - read from phy register
 * @netdev: network device to be read from
 * @mii_id: id of MII
 * @reg: PHY register
 *
 * Returns value read from PHY register
 *
 * spider_net_write_phy reads from an arbitrary PHY
 * register via the spider GPCROPCMD register
 **/
static int
spider_net_read_phy(struct net_device *netdev, int mii_id, int reg)
{
	struct spider_net_card *card = netdev_priv(netdev);
	u32 readvalue;

	readvalue = ((u32)mii_id << 21) | ((u32)reg << 16);
	spider_net_write_reg(card, SPIDER_NET_GPCROPCMD, readvalue);

	/* we don't use semaphores to wait for an SPIDER_NET_GPROPCMPINT
	 * interrupt, as we poll for the completion of the read operation
	 * in spider_net_read_phy. Should take about 50 us */
	do {
		readvalue = spider_net_read_reg(card, SPIDER_NET_GPCROPCMD);
	} while (readvalue & SPIDER_NET_GPREXEC);

	readvalue &= SPIDER_NET_GPRDAT_MASK;

	return readvalue;
}

/**
 * spider_net_setup_aneg - initial auto-negotiation setup
 * @card: device structure
 **/
static void
spider_net_setup_aneg(struct spider_net_card *card)
{
	struct mii_phy *phy = &card->phy;
	u32 advertise = 0;
	u16 bmsr, estat;

	bmsr  = spider_net_read_phy(card->netdev, phy->mii_id, MII_BMSR);
	estat = spider_net_read_phy(card->netdev, phy->mii_id, MII_ESTATUS);

	if (bmsr & BMSR_10HALF)
		advertise |= ADVERTISED_10baseT_Half;
	if (bmsr & BMSR_10FULL)
		advertise |= ADVERTISED_10baseT_Full;
	if (bmsr & BMSR_100HALF)
		advertise |= ADVERTISED_100baseT_Half;
	if (bmsr & BMSR_100FULL)
		advertise |= ADVERTISED_100baseT_Full;

	if ((bmsr & BMSR_ESTATEN) && (estat & ESTATUS_1000_TFULL))
		advertise |= SUPPORTED_1000baseT_Full;
	if ((bmsr & BMSR_ESTATEN) && (estat & ESTATUS_1000_THALF))
		advertise |= SUPPORTED_1000baseT_Half;

	sungem_phy_probe(phy, phy->mii_id);
	phy->def->ops->setup_aneg(phy, advertise);

}

/**
 * spider_net_rx_irq_off - switch off rx irq on this spider card
 * @card: device structure
 *
 * switches off rx irq by masking them out in the GHIINTnMSK register
 */
static void
spider_net_rx_irq_off(struct spider_net_card *card)
{
	u32 regvalue;

	regvalue = SPIDER_NET_INT0_MASK_VALUE & (~SPIDER_NET_RXINT);
	spider_net_write_reg(card, SPIDER_NET_GHIINT0MSK, regvalue);
}

/**
 * spider_net_rx_irq_on - switch on rx irq on this spider card
 * @card: device structure
 *
 * switches on rx irq by enabling them in the GHIINTnMSK register
 */
static void
spider_net_rx_irq_on(struct spider_net_card *card)
{
	u32 regvalue;

	regvalue = SPIDER_NET_INT0_MASK_VALUE | SPIDER_NET_RXINT;
	spider_net_write_reg(card, SPIDER_NET_GHIINT0MSK, regvalue);
}

/**
 * spider_net_set_promisc - sets the unicast address or the promiscuous mode
 * @card: card structure
 *
 * spider_net_set_promisc sets the unicast destination address filter and
 * thus either allows for non-promisc mode or promisc mode
 */
static void
spider_net_set_promisc(struct spider_net_card *card)
{
	u32 macu, macl;
	struct net_device *netdev = card->netdev;

	if (netdev->flags & IFF_PROMISC) {
		/* clear destination entry 0 */
		spider_net_write_reg(card, SPIDER_NET_GMRUAFILnR, 0);
		spider_net_write_reg(card, SPIDER_NET_GMRUAFILnR + 0x04, 0);
		spider_net_write_reg(card, SPIDER_NET_GMRUA0FIL15R,
				     SPIDER_NET_PROMISC_VALUE);
	} else {
		macu = netdev->dev_addr[0];
		macu <<= 8;
		macu |= netdev->dev_addr[1];
		memcpy(&macl, &netdev->dev_addr[2], sizeof(macl));

		macu |= SPIDER_NET_UA_DESCR_VALUE;
		spider_net_write_reg(card, SPIDER_NET_GMRUAFILnR, macu);
		spider_net_write_reg(card, SPIDER_NET_GMRUAFILnR + 0x04, macl);
		spider_net_write_reg(card, SPIDER_NET_GMRUA0FIL15R,
				     SPIDER_NET_NONPROMISC_VALUE);
	}
}

/**
 * spider_net_get_descr_status -- returns the status of a descriptor
 * @descr: descriptor to look at
 *
 * returns the status as in the dmac_cmd_status field of the descriptor
 */
static inline int
spider_net_get_descr_status(struct spider_net_hw_descr *hwdescr)
{
	return hwdescr->dmac_cmd_status & SPIDER_NET_DESCR_IND_PROC_MASK;
}

/**
 * spider_net_free_chain - free descriptor chain
 * @card: card structure
 * @chain: address of chain
 *
 */
static void
spider_net_free_chain(struct spider_net_card *card,
		      struct spider_net_descr_chain *chain)
{
	struct spider_net_descr *descr;

	descr = chain->ring;
	do {
		descr->bus_addr = 0;
		descr->hwdescr->next_descr_addr = 0;
		descr = descr->next;
	} while (descr != chain->ring);

	dma_free_coherent(&card->pdev->dev, chain->num_desc,
	    chain->hwring, chain->dma_addr);
}

/**
 * spider_net_init_chain - alloc and link descriptor chain
 * @card: card structure
 * @chain: address of chain
 *
 * We manage a circular list that mirrors the hardware structure,
 * except that the hardware uses bus addresses.
 *
 * Returns 0 on success, <0 on failure
 */
static int
spider_net_init_chain(struct spider_net_card *card,
		       struct spider_net_descr_chain *chain)
{
	int i;
	struct spider_net_descr *descr;
	struct spider_net_hw_descr *hwdescr;
	dma_addr_t buf;
	size_t alloc_size;

	alloc_size = chain->num_desc * sizeof(struct spider_net_hw_descr);

	chain->hwring = dma_alloc_coherent(&card->pdev->dev, alloc_size,
					   &chain->dma_addr, GFP_KERNEL);
	if (!chain->hwring)
		return -ENOMEM;

	memset(chain->ring, 0, chain->num_desc * sizeof(struct spider_net_descr));

	/* Set up the hardware pointers in each descriptor */
	descr = chain->ring;
	hwdescr = chain->hwring;
	buf = chain->dma_addr;
	for (i=0; i < chain->num_desc; i++, descr++, hwdescr++) {
		hwdescr->dmac_cmd_status = SPIDER_NET_DESCR_NOT_IN_USE;
		hwdescr->next_descr_addr = 0;

		descr->hwdescr = hwdescr;
		descr->bus_addr = buf;
		descr->next = descr + 1;
		descr->prev = descr - 1;

		buf += sizeof(struct spider_net_hw_descr);
	}
	/* do actual circular list */
	(descr-1)->next = chain->ring;
	chain->ring->prev = descr-1;

	spin_lock_init(&chain->lock);
	chain->head = chain->ring;
	chain->tail = chain->ring;
	return 0;
}

/**
 * spider_net_free_rx_chain_contents - frees descr contents in rx chain
 * @card: card structure
 *
 * returns 0 on success, <0 on failure
 */
static void
spider_net_free_rx_chain_contents(struct spider_net_card *card)
{
	struct spider_net_descr *descr;

	descr = card->rx_chain.head;
	do {
		if (descr->skb) {
			pci_unmap_single(card->pdev, descr->hwdescr->buf_addr,
					 SPIDER_NET_MAX_FRAME,
					 PCI_DMA_BIDIRECTIONAL);
			dev_kfree_skb(descr->skb);
			descr->skb = NULL;
		}
		descr = descr->next;
	} while (descr != card->rx_chain.head);
}

/**
 * spider_net_prepare_rx_descr - Reinitialize RX descriptor
 * @card: card structure
 * @descr: descriptor to re-init
 *
 * Return 0 on success, <0 on failure.
 *
 * Allocates a new rx skb, iommu-maps it and attaches it to the
 * descriptor. Mark the descriptor as activated, ready-to-use.
 */
static int
spider_net_prepare_rx_descr(struct spider_net_card *card,
			    struct spider_net_descr *descr)
{
	struct spider_net_hw_descr *hwdescr = descr->hwdescr;
	dma_addr_t buf;
	int offset;
	int bufsize;

	/* we need to round up the buffer size to a multiple of 128 */
	bufsize = (SPIDER_NET_MAX_FRAME + SPIDER_NET_RXBUF_ALIGN - 1) &
		(~(SPIDER_NET_RXBUF_ALIGN - 1));

	/* and we need to have it 128 byte aligned, therefore we allocate a
	 * bit more */
	/* allocate an skb */
	descr->skb = netdev_alloc_skb(card->netdev,
				      bufsize + SPIDER_NET_RXBUF_ALIGN - 1);
	if (!descr->skb) {
		if (netif_msg_rx_err(card) && net_ratelimit())
			dev_err(&card->netdev->dev,
			        "Not enough memory to allocate rx buffer\n");
		card->spider_stats.alloc_rx_skb_error++;
		return -ENOMEM;
	}
	hwdescr->buf_size = bufsize;
	hwdescr->result_size = 0;
	hwdescr->valid_size = 0;
	hwdescr->data_status = 0;
	hwdescr->data_error = 0;

	offset = ((unsigned long)descr->skb->data) &
		(SPIDER_NET_RXBUF_ALIGN - 1);
	if (offset)
		skb_reserve(descr->skb, SPIDER_NET_RXBUF_ALIGN - offset);
	/* iommu-map the skb */
	buf = pci_map_single(card->pdev, descr->skb->data,
			SPIDER_NET_MAX_FRAME, PCI_DMA_FROMDEVICE);
	if (pci_dma_mapping_error(card->pdev, buf)) {
		dev_kfree_skb_any(descr->skb);
		descr->skb = NULL;
		if (netif_msg_rx_err(card) && net_ratelimit())
			dev_err(&card->netdev->dev, "Could not iommu-map rx buffer\n");
		card->spider_stats.rx_iommu_map_error++;
		hwdescr->dmac_cmd_status = SPIDER_NET_DESCR_NOT_IN_USE;
	} else {
		hwdescr->buf_addr = buf;
		wmb();
		hwdescr->dmac_cmd_status = SPIDER_NET_DESCR_CARDOWNED |
					 SPIDER_NET_DMAC_NOINTR_COMPLETE;
	}

	return 0;
}

/**
 * spider_net_enable_rxchtails - sets RX dmac chain tail addresses
 * @card: card structure
 *
 * spider_net_enable_rxchtails sets the RX DMAC chain tail addresses in the
 * chip by writing to the appropriate register. DMA is enabled in
 * spider_net_enable_rxdmac.
 */
static inline void
spider_net_enable_rxchtails(struct spider_net_card *card)
{
	/* assume chain is aligned correctly */
	spider_net_write_reg(card, SPIDER_NET_GDADCHA ,
			     card->rx_chain.tail->bus_addr);
}

/**
 * spider_net_enable_rxdmac - enables a receive DMA controller
 * @card: card structure
 *
 * spider_net_enable_rxdmac enables the DMA controller by setting RX_DMA_EN
 * in the GDADMACCNTR register
 */
static inline void
spider_net_enable_rxdmac(struct spider_net_card *card)
{
	wmb();
	spider_net_write_reg(card, SPIDER_NET_GDADMACCNTR,
			     SPIDER_NET_DMA_RX_VALUE);
}

/**
 * spider_net_disable_rxdmac - disables the receive DMA controller
 * @card: card structure
 *
 * spider_net_disable_rxdmac terminates processing on the DMA controller
 * by turing off the DMA controller, with the force-end flag set.
 */
static inline void
spider_net_disable_rxdmac(struct spider_net_card *card)
{
	spider_net_write_reg(card, SPIDER_NET_GDADMACCNTR,
			     SPIDER_NET_DMA_RX_FEND_VALUE);
}

/**
 * spider_net_refill_rx_chain - refills descriptors/skbs in the rx chains
 * @card: card structure
 *
 * refills descriptors in the rx chain: allocates skbs and iommu-maps them.
 */
static void
spider_net_refill_rx_chain(struct spider_net_card *card)
{
	struct spider_net_descr_chain *chain = &card->rx_chain;
	unsigned long flags;

	/* one context doing the refill (and a second context seeing that
	 * and omitting it) is ok. If called by NAPI, we'll be called again
	 * as spider_net_decode_one_descr is called several times. If some
	 * interrupt calls us, the NAPI is about to clean up anyway. */
	if (!spin_trylock_irqsave(&chain->lock, flags))
		return;

	while (spider_net_get_descr_status(chain->head->hwdescr) ==
			SPIDER_NET_DESCR_NOT_IN_USE) {
		if (spider_net_prepare_rx_descr(card, chain->head))
			break;
		chain->head = chain->head->next;
	}

	spin_unlock_irqrestore(&chain->lock, flags);
}

/**
 * spider_net_alloc_rx_skbs - Allocates rx skbs in rx descriptor chains
 * @card: card structure
 *
 * Returns 0 on success, <0 on failure.
 */
static int
spider_net_alloc_rx_skbs(struct spider_net_card *card)
{
	struct spider_net_descr_chain *chain = &card->rx_chain;
	struct spider_net_descr *start = chain->tail;
	struct spider_net_descr *descr = start;

	/* Link up the hardware chain pointers */
	do {
		descr->prev->hwdescr->next_descr_addr = descr->bus_addr;
		descr = descr->next;
	} while (descr != start);

	/* Put at least one buffer into the chain. if this fails,
	 * we've got a problem. If not, spider_net_refill_rx_chain
	 * will do the rest at the end of this function. */
	if (spider_net_prepare_rx_descr(card, chain->head))
		goto error;
	else
		chain->head = chain->head->next;

	/* This will allocate the rest of the rx buffers;
	 * if not, it's business as usual later on. */
	spider_net_refill_rx_chain(card);
	spider_net_enable_rxdmac(card);
	return 0;

error:
	spider_net_free_rx_chain_contents(card);
	return -ENOMEM;
}

/**
 * spider_net_get_multicast_hash - generates hash for multicast filter table
 * @addr: multicast address
 *
 * returns the hash value.
 *
 * spider_net_get_multicast_hash calculates a hash value for a given multicast
 * address, that is used to set the multicast filter tables
 */
static u8
spider_net_get_multicast_hash(struct net_device *netdev, __u8 *addr)
{
	u32 crc;
	u8 hash;
	char addr_for_crc[ETH_ALEN] = { 0, };
	int i, bit;

	for (i = 0; i < ETH_ALEN * 8; i++) {
		bit = (addr[i / 8] >> (i % 8)) & 1;
		addr_for_crc[ETH_ALEN - 1 - i / 8] += bit << (7 - (i % 8));
	}

	crc = crc32_be(~0, addr_for_crc, netdev->addr_len);

	hash = (crc >> 27);
	hash <<= 3;
	hash |= crc & 7;
	hash &= 0xff;

	return hash;
}

/**
 * spider_net_set_multi - sets multicast addresses and promisc flags
 * @netdev: interface device structure
 *
 * spider_net_set_multi configures multicast addresses as needed for the
 * netdev interface. It also sets up multicast, allmulti and promisc
 * flags appropriately
 */
static void
spider_net_set_multi(struct net_device *netdev)
{
	struct netdev_hw_addr *ha;
	u8 hash;
	int i;
	u32 reg;
	struct spider_net_card *card = netdev_priv(netdev);
	DECLARE_BITMAP(bitmask, SPIDER_NET_MULTICAST_HASHES) = {};

	spider_net_set_promisc(card);

	if (netdev->flags & IFF_ALLMULTI) {
		for (i = 0; i < SPIDER_NET_MULTICAST_HASHES; i++) {
			set_bit(i, bitmask);
		}
		goto write_hash;
	}

	/* well, we know, what the broadcast hash value is: it's xfd
	hash = spider_net_get_multicast_hash(netdev, netdev->broadcast); */
	set_bit(0xfd, bitmask);

	netdev_for_each_mc_addr(ha, netdev) {
		hash = spider_net_get_multicast_hash(netdev, ha->addr);
		set_bit(hash, bitmask);
	}

write_hash:
	for (i = 0; i < SPIDER_NET_MULTICAST_HASHES / 4; i++) {
		reg = 0;
		if (test_bit(i * 4, bitmask))
			reg += 0x08;
		reg <<= 8;
		if (test_bit(i * 4 + 1, bitmask))
			reg += 0x08;
		reg <<= 8;
		if (test_bit(i * 4 + 2, bitmask))
			reg += 0x08;
		reg <<= 8;
		if (test_bit(i * 4 + 3, bitmask))
			reg += 0x08;

		spider_net_write_reg(card, SPIDER_NET_GMRMHFILnR + i * 4, reg);
	}
}

/**
 * spider_net_prepare_tx_descr - fill tx descriptor with skb data
 * @card: card structure
 * @skb: packet to use
 *
 * returns 0 on success, <0 on failure.
 *
 * fills out the descriptor structure with skb data and len. Copies data,
 * if needed (32bit DMA!)
 */
static int
spider_net_prepare_tx_descr(struct spider_net_card *card,
			    struct sk_buff *skb)
{
	struct spider_net_descr_chain *chain = &card->tx_chain;
	struct spider_net_descr *descr;
	struct spider_net_hw_descr *hwdescr;
	dma_addr_t buf;
	unsigned long flags;

	buf = pci_map_single(card->pdev, skb->data, skb->len, PCI_DMA_TODEVICE);
	if (pci_dma_mapping_error(card->pdev, buf)) {
		if (netif_msg_tx_err(card) && net_ratelimit())
			dev_err(&card->netdev->dev, "could not iommu-map packet (%p, %i). "
				  "Dropping packet\n", skb->data, skb->len);
		card->spider_stats.tx_iommu_map_error++;
		return -ENOMEM;
	}

	spin_lock_irqsave(&chain->lock, flags);
	descr = card->tx_chain.head;
	if (descr->next == chain->tail->prev) {
		spin_unlock_irqrestore(&chain->lock, flags);
		pci_unmap_single(card->pdev, buf, skb->len, PCI_DMA_TODEVICE);
		return -ENOMEM;
	}
	hwdescr = descr->hwdescr;
	chain->head = descr->next;

	descr->skb = skb;
	hwdescr->buf_addr = buf;
	hwdescr->buf_size = skb->len;
	hwdescr->next_descr_addr = 0;
	hwdescr->data_status = 0;

	hwdescr->dmac_cmd_status =
			SPIDER_NET_DESCR_CARDOWNED | SPIDER_NET_DMAC_TXFRMTL;
	spin_unlock_irqrestore(&chain->lock, flags);

	if (skb->ip_summed == CHECKSUM_PARTIAL)
		switch (ip_hdr(skb)->protocol) {
		case IPPROTO_TCP:
			hwdescr->dmac_cmd_status |= SPIDER_NET_DMAC_TCP;
			break;
		case IPPROTO_UDP:
			hwdescr->dmac_cmd_status |= SPIDER_NET_DMAC_UDP;
			break;
		}

	/* Chain the bus address, so that the DMA engine finds this descr. */
	wmb();
	descr->prev->hwdescr->next_descr_addr = descr->bus_addr;

	netif_trans_update(card->netdev); /* set netdev watchdog timer */
	return 0;
}

static int
spider_net_set_low_watermark(struct spider_net_card *card)
{
	struct spider_net_descr *descr = card->tx_chain.tail;
	struct spider_net_hw_descr *hwdescr;
	unsigned long flags;
	int status;
	int cnt=0;
	int i;

	/* Measure the length of the queue. Measurement does not
	 * need to be precise -- does not need a lock. */
	while (descr != card->tx_chain.head) {
		status = descr->hwdescr->dmac_cmd_status & SPIDER_NET_DESCR_NOT_IN_USE;
		if (status == SPIDER_NET_DESCR_NOT_IN_USE)
			break;
		descr = descr->next;
		cnt++;
	}

	/* If TX queue is short, don't even bother with interrupts */
	if (cnt < card->tx_chain.num_desc/4)
		return cnt;

	/* Set low-watermark 3/4th's of the way into the queue. */
	descr = card->tx_chain.tail;
	cnt = (cnt*3)/4;
	for (i=0;i<cnt; i++)
		descr = descr->next;

	/* Set the new watermark, clear the old watermark */
	spin_lock_irqsave(&card->tx_chain.lock, flags);
	descr->hwdescr->dmac_cmd_status |= SPIDER_NET_DESCR_TXDESFLG;
	if (card->low_watermark && card->low_watermark != descr) {
		hwdescr = card->low_watermark->hwdescr;
		hwdescr->dmac_cmd_status =
		     hwdescr->dmac_cmd_status & ~SPIDER_NET_DESCR_TXDESFLG;
	}
	card->low_watermark = descr;
	spin_unlock_irqrestore(&card->tx_chain.lock, flags);
	return cnt;
}

/**
 * spider_net_release_tx_chain - processes sent tx descriptors
 * @card: adapter structure
 * @brutal: if set, don't care about whether descriptor seems to be in use
 *
 * returns 0 if the tx ring is empty, otherwise 1.
 *
 * spider_net_release_tx_chain releases the tx descriptors that spider has
 * finished with (if non-brutal) or simply release tx descriptors (if brutal).
 * If some other context is calling this function, we return 1 so that we're
 * scheduled again (if we were scheduled) and will not lose initiative.
 */
static int
spider_net_release_tx_chain(struct spider_net_card *card, int brutal)
{
	struct net_device *dev = card->netdev;
	struct spider_net_descr_chain *chain = &card->tx_chain;
	struct spider_net_descr *descr;
	struct spider_net_hw_descr *hwdescr;
	struct sk_buff *skb;
	u32 buf_addr;
	unsigned long flags;
	int status;

	while (1) {
		spin_lock_irqsave(&chain->lock, flags);
		if (chain->tail == chain->head) {
			spin_unlock_irqrestore(&chain->lock, flags);
			return 0;
		}
		descr = chain->tail;
		hwdescr = descr->hwdescr;

		status = spider_net_get_descr_status(hwdescr);
		switch (status) {
		case SPIDER_NET_DESCR_COMPLETE:
			dev->stats.tx_packets++;
			dev->stats.tx_bytes += descr->skb->len;
			break;

		case SPIDER_NET_DESCR_CARDOWNED:
			if (!brutal) {
				spin_unlock_irqrestore(&chain->lock, flags);
				return 1;
			}

			/* fallthrough, if we release the descriptors
			 * brutally (then we don't care about
			 * SPIDER_NET_DESCR_CARDOWNED) */

		case SPIDER_NET_DESCR_RESPONSE_ERROR:
		case SPIDER_NET_DESCR_PROTECTION_ERROR:
		case SPIDER_NET_DESCR_FORCE_END:
			if (netif_msg_tx_err(card))
				dev_err(&card->netdev->dev, "forcing end of tx descriptor "
				       "with status x%02x\n", status);
			dev->stats.tx_errors++;
			break;

		default:
			dev->stats.tx_dropped++;
			if (!brutal) {
				spin_unlock_irqrestore(&chain->lock, flags);
				return 1;
			}
		}

		chain->tail = descr->next;
		hwdescr->dmac_cmd_status |= SPIDER_NET_DESCR_NOT_IN_USE;
		skb = descr->skb;
		descr->skb = NULL;
		buf_addr = hwdescr->buf_addr;
		spin_unlock_irqrestore(&chain->lock, flags);

		/* unmap the skb */
		if (skb) {
			pci_unmap_single(card->pdev, buf_addr, skb->len,
					PCI_DMA_TODEVICE);
			dev_consume_skb_any(skb);
		}
	}
	return 0;
}

/**
 * spider_net_kick_tx_dma - enables TX DMA processing
 * @card: card structure
 *
 * This routine will start the transmit DMA running if
 * it is not already running. This routine ned only be
 * called when queueing a new packet to an empty tx queue.
 * Writes the current tx chain head as start address
 * of the tx descriptor chain and enables the transmission
 * DMA engine.
 */
static inline void
spider_net_kick_tx_dma(struct spider_net_card *card)
{
	struct spider_net_descr *descr;

	if (spider_net_read_reg(card, SPIDER_NET_GDTDMACCNTR) &
			SPIDER_NET_TX_DMA_EN)
		goto out;

	descr = card->tx_chain.tail;
	for (;;) {
		if (spider_net_get_descr_status(descr->hwdescr) ==
				SPIDER_NET_DESCR_CARDOWNED) {
			spider_net_write_reg(card, SPIDER_NET_GDTDCHA,
					descr->bus_addr);
			spider_net_write_reg(card, SPIDER_NET_GDTDMACCNTR,
					SPIDER_NET_DMA_TX_VALUE);
			break;
		}
		if (descr == card->tx_chain.head)
			break;
		descr = descr->next;
	}

out:
	mod_timer(&card->tx_timer, jiffies + SPIDER_NET_TX_TIMER);
}

/**
 * spider_net_xmit - transmits a frame over the device
 * @skb: packet to send out
 * @netdev: interface device structure
 *
 * returns NETDEV_TX_OK on success, NETDEV_TX_BUSY on failure
 */
static netdev_tx_t
spider_net_xmit(struct sk_buff *skb, struct net_device *netdev)
{
	int cnt;
	struct spider_net_card *card = netdev_priv(netdev);

	spider_net_release_tx_chain(card, 0);

	if (spider_net_prepare_tx_descr(card, skb) != 0) {
		netdev->stats.tx_dropped++;
		netif_stop_queue(netdev);
		return NETDEV_TX_BUSY;
	}

	cnt = spider_net_set_low_watermark(card);
	if (cnt < 5)
		spider_net_kick_tx_dma(card);
	return NETDEV_TX_OK;
}

/**
 * spider_net_cleanup_tx_ring - cleans up the TX ring
 * @card: card structure
 *
 * spider_net_cleanup_tx_ring is called by either the tx_timer
 * or from the NAPI polling routine.
 * This routine releases resources associted with transmitted
 * packets, including updating the queue tail pointer.
 */
static void
spider_net_cleanup_tx_ring(struct timer_list *t)
{
	struct spider_net_card *card = from_timer(card, t, tx_timer);
	if ((spider_net_release_tx_chain(card, 0) != 0) &&
	    (card->netdev->flags & IFF_UP)) {
		spider_net_kick_tx_dma(card);
		netif_wake_queue(card->netdev);
	}
}

/**
 * spider_net_do_ioctl - called for device ioctls
 * @netdev: interface device structure
 * @ifr: request parameter structure for ioctl
 * @cmd: command code for ioctl
 *
 * returns 0 on success, <0 on failure. Currently, we have no special ioctls.
 * -EOPNOTSUPP is returned, if an unknown ioctl was requested
 */
static int
spider_net_do_ioctl(struct net_device *netdev, struct ifreq *ifr, int cmd)
{
	switch (cmd) {
	default:
		return -EOPNOTSUPP;
	}
}

/**
 * spider_net_pass_skb_up - takes an skb from a descriptor and passes it on
 * @descr: descriptor to process
 * @card: card structure
 *
 * Fills out skb structure and passes the data to the stack.
 * The descriptor state is not changed.
 */
static void
spider_net_pass_skb_up(struct spider_net_descr *descr,
		       struct spider_net_card *card)
{
	struct spider_net_hw_descr *hwdescr = descr->hwdescr;
	struct sk_buff *skb = descr->skb;
	struct net_device *netdev = card->netdev;
	u32 data_status = hwdescr->data_status;
	u32 data_error = hwdescr->data_error;

	skb_put(skb, hwdescr->valid_size);

	/* the card seems to add 2 bytes of junk in front
	 * of the ethernet frame */
#define SPIDER_MISALIGN		2
	skb_pull(skb, SPIDER_MISALIGN);
	skb->protocol = eth_type_trans(skb, netdev);

	/* checksum offload */
	skb_checksum_none_assert(skb);
	if (netdev->features & NETIF_F_RXCSUM) {
		if ( ( (data_status & SPIDER_NET_DATA_STATUS_CKSUM_MASK) ==
		       SPIDER_NET_DATA_STATUS_CKSUM_MASK) &&
		     !(data_error & SPIDER_NET_DATA_ERR_CKSUM_MASK))
			skb->ip_summed = CHECKSUM_UNNECESSARY;
	}

	if (data_status & SPIDER_NET_VLAN_PACKET) {
		/* further enhancements: HW-accel VLAN */
	}

	/* update netdevice statistics */
	netdev->stats.rx_packets++;
	netdev->stats.rx_bytes += skb->len;

	/* pass skb up to stack */
	netif_receive_skb(skb);
}

static void show_rx_chain(struct spider_net_card *card)
{
	struct spider_net_descr_chain *chain = &card->rx_chain;
	struct spider_net_descr *start= chain->tail;
	struct spider_net_descr *descr= start;
	struct spider_net_hw_descr *hwd = start->hwdescr;
	struct device *dev = &card->netdev->dev;
	u32 curr_desc, next_desc;
	int status;

	int tot = 0;
	int cnt = 0;
	int off = start - chain->ring;
	int cstat = hwd->dmac_cmd_status;

	dev_info(dev, "Total number of descrs=%d\n",
		chain->num_desc);
	dev_info(dev, "Chain tail located at descr=%d, status=0x%x\n",
		off, cstat);

	curr_desc = spider_net_read_reg(card, SPIDER_NET_GDACTDPA);
	next_desc = spider_net_read_reg(card, SPIDER_NET_GDACNEXTDA);

	status = cstat;
	do
	{
		hwd = descr->hwdescr;
		off = descr - chain->ring;
		status = hwd->dmac_cmd_status;

		if (descr == chain->head)
			dev_info(dev, "Chain head is at %d, head status=0x%x\n",
			         off, status);

		if (curr_desc == descr->bus_addr)
			dev_info(dev, "HW curr desc (GDACTDPA) is at %d, status=0x%x\n",
			         off, status);

		if (next_desc == descr->bus_addr)
			dev_info(dev, "HW next desc (GDACNEXTDA) is at %d, status=0x%x\n",
			         off, status);

		if (hwd->next_descr_addr == 0)
			dev_info(dev, "chain is cut at %d\n", off);

		if (cstat != status) {
			int from = (chain->num_desc + off - cnt) % chain->num_desc;
			int to = (chain->num_desc + off - 1) % chain->num_desc;
			dev_info(dev, "Have %d (from %d to %d) descrs "
			         "with stat=0x%08x\n", cnt, from, to, cstat);
			cstat = status;
			cnt = 0;
		}

		cnt ++;
		tot ++;
		descr = descr->next;
	} while (descr != start);

	dev_info(dev, "Last %d descrs with stat=0x%08x "
	         "for a total of %d descrs\n", cnt, cstat, tot);

#ifdef DEBUG
	/* Now dump the whole ring */
	descr = start;
	do
	{
		struct spider_net_hw_descr *hwd = descr->hwdescr;
		status = spider_net_get_descr_status(hwd);
		cnt = descr - chain->ring;
		dev_info(dev, "Descr %d stat=0x%08x skb=%p\n",
		         cnt, status, descr->skb);
		dev_info(dev, "bus addr=%08x buf addr=%08x sz=%d\n",
		         descr->bus_addr, hwd->buf_addr, hwd->buf_size);
		dev_info(dev, "next=%08x result sz=%d valid sz=%d\n",
		         hwd->next_descr_addr, hwd->result_size,
		         hwd->valid_size);
		dev_info(dev, "dmac=%08x data stat=%08x data err=%08x\n",
		         hwd->dmac_cmd_status, hwd->data_status,
		         hwd->data_error);
		dev_info(dev, "\n");

		descr = descr->next;
	} while (descr != start);
#endif

}

/**
 * spider_net_resync_head_ptr - Advance head ptr past empty descrs
 *
 * If the driver fails to keep up and empty the queue, then the
 * hardware wil run out of room to put incoming packets. This
 * will cause the hardware to skip descrs that are full (instead
 * of halting/retrying). Thus, once the driver runs, it wil need
 * to "catch up" to where the hardware chain pointer is at.
 */
static void spider_net_resync_head_ptr(struct spider_net_card *card)
{
	unsigned long flags;
	struct spider_net_descr_chain *chain = &card->rx_chain;
	struct spider_net_descr *descr;
	int i, status;

	/* Advance head pointer past any empty descrs */
	descr = chain->head;
	status = spider_net_get_descr_status(descr->hwdescr);

	if (status == SPIDER_NET_DESCR_NOT_IN_USE)
		return;

	spin_lock_irqsave(&chain->lock, flags);

	descr = chain->head;
	status = spider_net_get_descr_status(descr->hwdescr);
	for (i=0; i<chain->num_desc; i++) {
		if (status != SPIDER_NET_DESCR_CARDOWNED) break;
		descr = descr->next;
		status = spider_net_get_descr_status(descr->hwdescr);
	}
	chain->head = descr;

	spin_unlock_irqrestore(&chain->lock, flags);
}

static int spider_net_resync_tail_ptr(struct spider_net_card *card)
{
	struct spider_net_descr_chain *chain = &card->rx_chain;
	struct spider_net_descr *descr;
	int i, status;

	/* Advance tail pointer past any empty and reaped descrs */
	descr = chain->tail;
	status = spider_net_get_descr_status(descr->hwdescr);

	for (i=0; i<chain->num_desc; i++) {
		if ((status != SPIDER_NET_DESCR_CARDOWNED) &&
		    (status != SPIDER_NET_DESCR_NOT_IN_USE)) break;
		descr = descr->next;
		status = spider_net_get_descr_status(descr->hwdescr);
	}
	chain->tail = descr;

	if ((i == chain->num_desc) || (i == 0))
		return 1;
	return 0;
}

/**
 * spider_net_decode_one_descr - processes an RX descriptor
 * @card: card structure
 *
 * Returns 1 if a packet has been sent to the stack, otherwise 0.
 *
 * Processes an RX descriptor by iommu-unmapping the data buffer
 * and passing the packet up to the stack. This function is called
 * in softirq context, e.g. either bottom half from interrupt or
 * NAPI polling context.
 */
static int
spider_net_decode_one_descr(struct spider_net_card *card)
{
	struct net_device *dev = card->netdev;
	struct spider_net_descr_chain *chain = &card->rx_chain;
	struct spider_net_descr *descr = chain->tail;
	struct spider_net_hw_descr *hwdescr = descr->hwdescr;
	u32 hw_buf_addr;
	int status;

	status = spider_net_get_descr_status(hwdescr);

	/* Nothing in the descriptor, or ring must be empty */
	if ((status == SPIDER_NET_DESCR_CARDOWNED) ||
	    (status == SPIDER_NET_DESCR_NOT_IN_USE))
		return 0;

	/* descriptor definitively used -- move on tail */
	chain->tail = descr->next;

	/* unmap descriptor */
	hw_buf_addr = hwdescr->buf_addr;
	hwdescr->buf_addr = 0xffffffff;
	pci_unmap_single(card->pdev, hw_buf_addr,
			SPIDER_NET_MAX_FRAME, PCI_DMA_FROMDEVICE);

	if ( (status == SPIDER_NET_DESCR_RESPONSE_ERROR) ||
	     (status == SPIDER_NET_DESCR_PROTECTION_ERROR) ||
	     (status == SPIDER_NET_DESCR_FORCE_END) ) {
		if (netif_msg_rx_err(card))
			dev_err(&dev->dev,
			       "dropping RX descriptor with state %d\n", status);
		dev->stats.rx_dropped++;
		goto bad_desc;
	}

	if ( (status != SPIDER_NET_DESCR_COMPLETE) &&
	     (status != SPIDER_NET_DESCR_FRAME_END) ) {
		if (netif_msg_rx_err(card))
			dev_err(&card->netdev->dev,
			       "RX descriptor with unknown state %d\n", status);
		card->spider_stats.rx_desc_unk_state++;
		goto bad_desc;
	}

	/* The cases we'll throw away the packet immediately */
	if (hwdescr->data_error & SPIDER_NET_DESTROY_RX_FLAGS) {
		if (netif_msg_rx_err(card))
			dev_err(&card->netdev->dev,
			       "error in received descriptor found, "
			       "data_status=x%08x, data_error=x%08x\n",
			       hwdescr->data_status, hwdescr->data_error);
		goto bad_desc;
	}

	if (hwdescr->dmac_cmd_status & SPIDER_NET_DESCR_BAD_STATUS) {
		dev_err(&card->netdev->dev, "bad status, cmd_status=x%08x\n",
			       hwdescr->dmac_cmd_status);
		pr_err("buf_addr=x%08x\n", hw_buf_addr);
		pr_err("buf_size=x%08x\n", hwdescr->buf_size);
		pr_err("next_descr_addr=x%08x\n", hwdescr->next_descr_addr);
		pr_err("result_size=x%08x\n", hwdescr->result_size);
		pr_err("valid_size=x%08x\n", hwdescr->valid_size);
		pr_err("data_status=x%08x\n", hwdescr->data_status);
		pr_err("data_error=x%08x\n", hwdescr->data_error);
		pr_err("which=%ld\n", descr - card->rx_chain.ring);

		card->spider_stats.rx_desc_error++;
		goto bad_desc;
	}

	/* Ok, we've got a packet in descr */
	spider_net_pass_skb_up(descr, card);
	descr->skb = NULL;
	hwdescr->dmac_cmd_status = SPIDER_NET_DESCR_NOT_IN_USE;
	return 1;

bad_desc:
	if (netif_msg_rx_err(card))
		show_rx_chain(card);
	dev_kfree_skb_irq(descr->skb);
	descr->skb = NULL;
	hwdescr->dmac_cmd_status = SPIDER_NET_DESCR_NOT_IN_USE;
	return 0;
}

/**
 * spider_net_poll - NAPI poll function called by the stack to return packets
 * @netdev: interface device structure
 * @budget: number of packets we can pass to the stack at most
 *
 * returns 0 if no more packets available to the driver/stack. Returns 1,
 * if the quota is exceeded, but the driver has still packets.
 *
 * spider_net_poll returns all packets from the rx descriptors to the stack
 * (using netif_receive_skb). If all/enough packets are up, the driver
 * reenables interrupts and returns 0. If not, 1 is returned.
 */
static int spider_net_poll(struct napi_struct *napi, int budget)
{
	struct spider_net_card *card = container_of(napi, struct spider_net_card, napi);
	int packets_done = 0;

	while (packets_done < budget) {
		if (!spider_net_decode_one_descr(card))
			break;

		packets_done++;
	}

	if ((packets_done == 0) && (card->num_rx_ints != 0)) {
		if (!spider_net_resync_tail_ptr(card))
			packets_done = budget;
		spider_net_resync_head_ptr(card);
	}
	card->num_rx_ints = 0;

	spider_net_refill_rx_chain(card);
	spider_net_enable_rxdmac(card);

	spider_net_cleanup_tx_ring(&card->tx_timer);

	/* if all packets are in the stack, enable interrupts and return 0 */
	/* if not, return 1 */
	if (packets_done < budget) {
		napi_complete_done(napi, packets_done);
		spider_net_rx_irq_on(card);
		card->ignore_rx_ramfull = 0;
	}

	return packets_done;
}

/**
 * spider_net_set_mac - sets the MAC of an interface
 * @netdev: interface device structure
 * @ptr: pointer to new MAC address
 *
 * Returns 0 on success, <0 on failure. Currently, we don't support this
 * and will always return EOPNOTSUPP.
 */
static int
spider_net_set_mac(struct net_device *netdev, void *p)
{
	struct spider_net_card *card = netdev_priv(netdev);
	u32 macl, macu, regvalue;
	struct sockaddr *addr = p;

	if (!is_valid_ether_addr(addr->sa_data))
		return -EADDRNOTAVAIL;

	memcpy(netdev->dev_addr, addr->sa_data, ETH_ALEN);

	/* switch off GMACTPE and GMACRPE */
	regvalue = spider_net_read_reg(card, SPIDER_NET_GMACOPEMD);
	regvalue &= ~((1 << 5) | (1 << 6));
	spider_net_write_reg(card, SPIDER_NET_GMACOPEMD, regvalue);

	/* write mac */
	macu = (netdev->dev_addr[0]<<24) + (netdev->dev_addr[1]<<16) +
		(netdev->dev_addr[2]<<8) + (netdev->dev_addr[3]);
	macl = (netdev->dev_addr[4]<<8) + (netdev->dev_addr[5]);
	spider_net_write_reg(card, SPIDER_NET_GMACUNIMACU, macu);
	spider_net_write_reg(card, SPIDER_NET_GMACUNIMACL, macl);

	/* switch GMACTPE and GMACRPE back on */
	regvalue = spider_net_read_reg(card, SPIDER_NET_GMACOPEMD);
	regvalue |= ((1 << 5) | (1 << 6));
	spider_net_write_reg(card, SPIDER_NET_GMACOPEMD, regvalue);

	spider_net_set_promisc(card);

	return 0;
}

/**
 * spider_net_link_reset
 * @netdev: net device structure
 *
 * This is called when the PHY_LINK signal is asserted. For the blade this is
 * not connected so we should never get here.
 *
 */
static void
spider_net_link_reset(struct net_device *netdev)
{

	struct spider_net_card *card = netdev_priv(netdev);

	del_timer_sync(&card->aneg_timer);

	/* clear interrupt, block further interrupts */
	spider_net_write_reg(card, SPIDER_NET_GMACST,
			     spider_net_read_reg(card, SPIDER_NET_GMACST));
	spider_net_write_reg(card, SPIDER_NET_GMACINTEN, 0);

	/* reset phy and setup aneg */
	card->aneg_count = 0;
	card->medium = BCM54XX_COPPER;
	spider_net_setup_aneg(card);
	mod_timer(&card->aneg_timer, jiffies + SPIDER_NET_ANEG_TIMER);

}

/**
 * spider_net_handle_error_irq - handles errors raised by an interrupt
 * @card: card structure
 * @status_reg: interrupt status register 0 (GHIINT0STS)
 *
 * spider_net_handle_error_irq treats or ignores all error conditions
 * found when an interrupt is presented
 */
static void
spider_net_handle_error_irq(struct spider_net_card *card, u32 status_reg,
			    u32 error_reg1, u32 error_reg2)
{
	u32 i;
	int show_error = 1;

	/* check GHIINT0STS ************************************/
	if (status_reg)
		for (i = 0; i < 32; i++)
			if (status_reg & (1<<i))
				switch (i)
	{
	/* let error_reg1 and error_reg2 evaluation decide, what to do
	case SPIDER_NET_PHYINT:
	case SPIDER_NET_GMAC2INT:
	case SPIDER_NET_GMAC1INT:
	case SPIDER_NET_GFIFOINT:
	case SPIDER_NET_DMACINT:
	case SPIDER_NET_GSYSINT:
		break; */

	case SPIDER_NET_GIPSINT:
		show_error = 0;
		break;

	case SPIDER_NET_GPWOPCMPINT:
		/* PHY write operation completed */
		show_error = 0;
		break;
	case SPIDER_NET_GPROPCMPINT:
		/* PHY read operation completed */
		/* we don't use semaphores, as we poll for the completion
		 * of the read operation in spider_net_read_phy. Should take
		 * about 50 us */
		show_error = 0;
		break;
	case SPIDER_NET_GPWFFINT:
		/* PHY command queue full */
		if (netif_msg_intr(card))
			dev_err(&card->netdev->dev, "PHY write queue full\n");
		show_error = 0;
		break;

	/* case SPIDER_NET_GRMDADRINT: not used. print a message */
	/* case SPIDER_NET_GRMARPINT: not used. print a message */
	/* case SPIDER_NET_GRMMPINT: not used. print a message */

	case SPIDER_NET_GDTDEN0INT:
		/* someone has set TX_DMA_EN to 0 */
		show_error = 0;
		break;

	case SPIDER_NET_GDDDEN0INT: /* fallthrough */
	case SPIDER_NET_GDCDEN0INT: /* fallthrough */
	case SPIDER_NET_GDBDEN0INT: /* fallthrough */
	case SPIDER_NET_GDADEN0INT:
		/* someone has set RX_DMA_EN to 0 */
		show_error = 0;
		break;

	/* RX interrupts */
	case SPIDER_NET_GDDFDCINT:
	case SPIDER_NET_GDCFDCINT:
	case SPIDER_NET_GDBFDCINT:
	case SPIDER_NET_GDAFDCINT:
	/* case SPIDER_NET_GDNMINT: not used. print a message */
	/* case SPIDER_NET_GCNMINT: not used. print a message */
	/* case SPIDER_NET_GBNMINT: not used. print a message */
	/* case SPIDER_NET_GANMINT: not used. print a message */
	/* case SPIDER_NET_GRFNMINT: not used. print a message */
		show_error = 0;
		break;

	/* TX interrupts */
	case SPIDER_NET_GDTFDCINT:
		show_error = 0;
		break;
	case SPIDER_NET_GTTEDINT:
		show_error = 0;
		break;
	case SPIDER_NET_GDTDCEINT:
		/* chain end. If a descriptor should be sent, kick off
		 * tx dma
		if (card->tx_chain.tail != card->tx_chain.head)
			spider_net_kick_tx_dma(card);
		*/
		show_error = 0;
		break;

	/* case SPIDER_NET_G1TMCNTINT: not used. print a message */
	/* case SPIDER_NET_GFREECNTINT: not used. print a message */
	}

	/* check GHIINT1STS ************************************/
	if (error_reg1)
		for (i = 0; i < 32; i++)
			if (error_reg1 & (1<<i))
				switch (i)
	{
	case SPIDER_NET_GTMFLLINT:
		/* TX RAM full may happen on a usual case.
		 * Logging is not needed. */
		show_error = 0;
		break;
	case SPIDER_NET_GRFDFLLINT: /* fallthrough */
	case SPIDER_NET_GRFCFLLINT: /* fallthrough */
	case SPIDER_NET_GRFBFLLINT: /* fallthrough */
	case SPIDER_NET_GRFAFLLINT: /* fallthrough */
	case SPIDER_NET_GRMFLLINT:
		/* Could happen when rx chain is full */
		if (card->ignore_rx_ramfull == 0) {
			card->ignore_rx_ramfull = 1;
			spider_net_resync_head_ptr(card);
			spider_net_refill_rx_chain(card);
			spider_net_enable_rxdmac(card);
			card->num_rx_ints ++;
			napi_schedule(&card->napi);
		}
		show_error = 0;
		break;

	/* case SPIDER_NET_GTMSHTINT: problem, print a message */
	case SPIDER_NET_GDTINVDINT:
		/* allrighty. tx from previous descr ok */
		show_error = 0;
		break;

	/* chain end */
	case SPIDER_NET_GDDDCEINT: /* fallthrough */
	case SPIDER_NET_GDCDCEINT: /* fallthrough */
	case SPIDER_NET_GDBDCEINT: /* fallthrough */
	case SPIDER_NET_GDADCEINT:
		spider_net_resync_head_ptr(card);
		spider_net_refill_rx_chain(card);
		spider_net_enable_rxdmac(card);
		card->num_rx_ints ++;
		napi_schedule(&card->napi);
		show_error = 0;
		break;

	/* invalid descriptor */
	case SPIDER_NET_GDDINVDINT: /* fallthrough */
	case SPIDER_NET_GDCINVDINT: /* fallthrough */
	case SPIDER_NET_GDBINVDINT: /* fallthrough */
	case SPIDER_NET_GDAINVDINT:
		/* Could happen when rx chain is full */
		spider_net_resync_head_ptr(card);
		spider_net_refill_rx_chain(card);
		spider_net_enable_rxdmac(card);
		card->num_rx_ints ++;
		napi_schedule(&card->napi);
		show_error = 0;
		break;

	/* case SPIDER_NET_GDTRSERINT: problem, print a message */
	/* case SPIDER_NET_GDDRSERINT: problem, print a message */
	/* case SPIDER_NET_GDCRSERINT: problem, print a message */
	/* case SPIDER_NET_GDBRSERINT: problem, print a message */
	/* case SPIDER_NET_GDARSERINT: problem, print a message */
	/* case SPIDER_NET_GDSERINT: problem, print a message */
	/* case SPIDER_NET_GDTPTERINT: problem, print a message */
	/* case SPIDER_NET_GDDPTERINT: problem, print a message */
	/* case SPIDER_NET_GDCPTERINT: problem, print a message */
	/* case SPIDER_NET_GDBPTERINT: problem, print a message */
	/* case SPIDER_NET_GDAPTERINT: problem, print a message */
	default:
		show_error = 1;
		break;
	}

	/* check GHIINT2STS ************************************/
	if (error_reg2)
		for (i = 0; i < 32; i++)
			if (error_reg2 & (1<<i))
				switch (i)
	{
	/* there is nothing we can (want  to) do at this time. Log a
	 * message, we can switch on and off the specific values later on
	case SPIDER_NET_GPROPERINT:
	case SPIDER_NET_GMCTCRSNGINT:
	case SPIDER_NET_GMCTLCOLINT:
	case SPIDER_NET_GMCTTMOTINT:
	case SPIDER_NET_GMCRCAERINT:
	case SPIDER_NET_GMCRCALERINT:
	case SPIDER_NET_GMCRALNERINT:
	case SPIDER_NET_GMCROVRINT:
	case SPIDER_NET_GMCRRNTINT:
	case SPIDER_NET_GMCRRXERINT:
	case SPIDER_NET_GTITCSERINT:
	case SPIDER_NET_GTIFMTERINT:
	case SPIDER_NET_GTIPKTRVKINT:
	case SPIDER_NET_GTISPINGINT:
	case SPIDER_NET_GTISADNGINT:
	case SPIDER_NET_GTISPDNGINT:
	case SPIDER_NET_GRIFMTERINT:
	case SPIDER_NET_GRIPKTRVKINT:
	case SPIDER_NET_GRISPINGINT:
	case SPIDER_NET_GRISADNGINT:
	case SPIDER_NET_GRISPDNGINT:
		break;
	*/
		default:
			break;
	}

	if ((show_error) && (netif_msg_intr(card)) && net_ratelimit())
		dev_err(&card->netdev->dev, "Error interrupt, GHIINT0STS = 0x%08x, "
		       "GHIINT1STS = 0x%08x, GHIINT2STS = 0x%08x\n",
		       status_reg, error_reg1, error_reg2);

	/* clear interrupt sources */
	spider_net_write_reg(card, SPIDER_NET_GHIINT1STS, error_reg1);
	spider_net_write_reg(card, SPIDER_NET_GHIINT2STS, error_reg2);
}

/**
 * spider_net_interrupt - interrupt handler for spider_net
 * @irq: interrupt number
 * @ptr: pointer to net_device
 *
 * returns IRQ_HANDLED, if interrupt was for driver, or IRQ_NONE, if no
 * interrupt found raised by card.
 *
 * This is the interrupt handler, that turns off
 * interrupts for this device and makes the stack poll the driver
 */
static irqreturn_t
spider_net_interrupt(int irq, void *ptr)
{
	struct net_device *netdev = ptr;
	struct spider_net_card *card = netdev_priv(netdev);
	u32 status_reg, error_reg1, error_reg2;

	status_reg = spider_net_read_reg(card, SPIDER_NET_GHIINT0STS);
	error_reg1 = spider_net_read_reg(card, SPIDER_NET_GHIINT1STS);
	error_reg2 = spider_net_read_reg(card, SPIDER_NET_GHIINT2STS);

	if (!(status_reg & SPIDER_NET_INT0_MASK_VALUE) &&
	    !(error_reg1 & SPIDER_NET_INT1_MASK_VALUE) &&
	    !(error_reg2 & SPIDER_NET_INT2_MASK_VALUE))
		return IRQ_NONE;

	if (status_reg & SPIDER_NET_RXINT ) {
		spider_net_rx_irq_off(card);
		napi_schedule(&card->napi);
		card->num_rx_ints ++;
	}
	if (status_reg & SPIDER_NET_TXINT)
		napi_schedule(&card->napi);

	if (status_reg & SPIDER_NET_LINKINT)
		spider_net_link_reset(netdev);

	if (status_reg & SPIDER_NET_ERRINT )
		spider_net_handle_error_irq(card, status_reg,
					    error_reg1, error_reg2);

	/* clear interrupt sources */
	spider_net_write_reg(card, SPIDER_NET_GHIINT0STS, status_reg);

	return IRQ_HANDLED;
}

#ifdef CONFIG_NET_POLL_CONTROLLER
/**
 * spider_net_poll_controller - artificial interrupt for netconsole etc.
 * @netdev: interface device structure
 *
 * see Documentation/networking/netconsole.txt
 */
static void
spider_net_poll_controller(struct net_device *netdev)
{
	disable_irq(netdev->irq);
	spider_net_interrupt(netdev->irq, netdev);
	enable_irq(netdev->irq);
}
#endif /* CONFIG_NET_POLL_CONTROLLER */

/**
 * spider_net_enable_interrupts - enable interrupts
 * @card: card structure
 *
 * spider_net_enable_interrupt enables several interrupts
 */
static void
spider_net_enable_interrupts(struct spider_net_card *card)
{
	spider_net_write_reg(card, SPIDER_NET_GHIINT0MSK,
			     SPIDER_NET_INT0_MASK_VALUE);
	spider_net_write_reg(card, SPIDER_NET_GHIINT1MSK,
			     SPIDER_NET_INT1_MASK_VALUE);
	spider_net_write_reg(card, SPIDER_NET_GHIINT2MSK,
			     SPIDER_NET_INT2_MASK_VALUE);
}

/**
 * spider_net_disable_interrupts - disable interrupts
 * @card: card structure
 *
 * spider_net_disable_interrupts disables all the interrupts
 */
static void
spider_net_disable_interrupts(struct spider_net_card *card)
{
	spider_net_write_reg(card, SPIDER_NET_GHIINT0MSK, 0);
	spider_net_write_reg(card, SPIDER_NET_GHIINT1MSK, 0);
	spider_net_write_reg(card, SPIDER_NET_GHIINT2MSK, 0);
	spider_net_write_reg(card, SPIDER_NET_GMACINTEN, 0);
}

/**
 * spider_net_init_card - initializes the card
 * @card: card structure
 *
 * spider_net_init_card initializes the card so that other registers can
 * be used
 */
static void
spider_net_init_card(struct spider_net_card *card)
{
	spider_net_write_reg(card, SPIDER_NET_CKRCTRL,
			     SPIDER_NET_CKRCTRL_STOP_VALUE);

	spider_net_write_reg(card, SPIDER_NET_CKRCTRL,
			     SPIDER_NET_CKRCTRL_RUN_VALUE);

	/* trigger ETOMOD signal */
	spider_net_write_reg(card, SPIDER_NET_GMACOPEMD,
		spider_net_read_reg(card, SPIDER_NET_GMACOPEMD) | 0x4);

	spider_net_disable_interrupts(card);
}

/**
 * spider_net_enable_card - enables the card by setting all kinds of regs
 * @card: card structure
 *
 * spider_net_enable_card sets a lot of SMMIO registers to enable the device
 */
static void
spider_net_enable_card(struct spider_net_card *card)
{
	int i;
	/* the following array consists of (register),(value) pairs
	 * that are set in this function. A register of 0 ends the list */
	u32 regs[][2] = {
		{ SPIDER_NET_GRESUMINTNUM, 0 },
		{ SPIDER_NET_GREINTNUM, 0 },

		/* set interrupt frame number registers */
		/* clear the single DMA engine registers first */
		{ SPIDER_NET_GFAFRMNUM, SPIDER_NET_GFXFRAMES_VALUE },
		{ SPIDER_NET_GFBFRMNUM, SPIDER_NET_GFXFRAMES_VALUE },
		{ SPIDER_NET_GFCFRMNUM, SPIDER_NET_GFXFRAMES_VALUE },
		{ SPIDER_NET_GFDFRMNUM, SPIDER_NET_GFXFRAMES_VALUE },
		/* then set, what we really need */
		{ SPIDER_NET_GFFRMNUM, SPIDER_NET_FRAMENUM_VALUE },

		/* timer counter registers and stuff */
		{ SPIDER_NET_GFREECNNUM, 0 },
		{ SPIDER_NET_GONETIMENUM, 0 },
		{ SPIDER_NET_GTOUTFRMNUM, 0 },

		/* RX mode setting */
		{ SPIDER_NET_GRXMDSET, SPIDER_NET_RXMODE_VALUE },
		/* TX mode setting */
		{ SPIDER_NET_GTXMDSET, SPIDER_NET_TXMODE_VALUE },
		/* IPSEC mode setting */
		{ SPIDER_NET_GIPSECINIT, SPIDER_NET_IPSECINIT_VALUE },

		{ SPIDER_NET_GFTRESTRT, SPIDER_NET_RESTART_VALUE },

		{ SPIDER_NET_GMRWOLCTRL, 0 },
		{ SPIDER_NET_GTESTMD, 0x10000000 },
		{ SPIDER_NET_GTTQMSK, 0x00400040 },

		{ SPIDER_NET_GMACINTEN, 0 },

		/* flow control stuff */
		{ SPIDER_NET_GMACAPAUSE, SPIDER_NET_MACAPAUSE_VALUE },
		{ SPIDER_NET_GMACTXPAUSE, SPIDER_NET_TXPAUSE_VALUE },

		{ SPIDER_NET_GMACBSTLMT, SPIDER_NET_BURSTLMT_VALUE },
		{ 0, 0}
	};

	i = 0;
	while (regs[i][0]) {
		spider_net_write_reg(card, regs[i][0], regs[i][1]);
		i++;
	}

	/* clear unicast filter table entries 1 to 14 */
	for (i = 1; i <= 14; i++) {
		spider_net_write_reg(card,
				     SPIDER_NET_GMRUAFILnR + i * 8,
				     0x00080000);
		spider_net_write_reg(card,
				     SPIDER_NET_GMRUAFILnR + i * 8 + 4,
				     0x00000000);
	}

	spider_net_write_reg(card, SPIDER_NET_GMRUA0FIL15R, 0x08080000);

	spider_net_write_reg(card, SPIDER_NET_ECMODE, SPIDER_NET_ECMODE_VALUE);

	/* set chain tail address for RX chains and
	 * enable DMA */
	spider_net_enable_rxchtails(card);
	spider_net_enable_rxdmac(card);

	spider_net_write_reg(card, SPIDER_NET_GRXDMAEN, SPIDER_NET_WOL_VALUE);

	spider_net_write_reg(card, SPIDER_NET_GMACLENLMT,
			     SPIDER_NET_LENLMT_VALUE);
	spider_net_write_reg(card, SPIDER_NET_GMACOPEMD,
			     SPIDER_NET_OPMODE_VALUE);

	spider_net_write_reg(card, SPIDER_NET_GDTDMACCNTR,
			     SPIDER_NET_GDTBSTA);
}

/**
 * spider_net_download_firmware - loads firmware into the adapter
 * @card: card structure
 * @firmware_ptr: pointer to firmware data
 *
 * spider_net_download_firmware loads the firmware data into the
 * adapter. It assumes the length etc. to be allright.
 */
static int
spider_net_download_firmware(struct spider_net_card *card,
			     const void *firmware_ptr)
{
	int sequencer, i;
	const u32 *fw_ptr = firmware_ptr;

	/* stop sequencers */
	spider_net_write_reg(card, SPIDER_NET_GSINIT,
			     SPIDER_NET_STOP_SEQ_VALUE);

	for (sequencer = 0; sequencer < SPIDER_NET_FIRMWARE_SEQS;
	     sequencer++) {
		spider_net_write_reg(card,
				     SPIDER_NET_GSnPRGADR + sequencer * 8, 0);
		for (i = 0; i < SPIDER_NET_FIRMWARE_SEQWORDS; i++) {
			spider_net_write_reg(card, SPIDER_NET_GSnPRGDAT +
					     sequencer * 8, *fw_ptr);
			fw_ptr++;
		}
	}

	if (spider_net_read_reg(card, SPIDER_NET_GSINIT))
		return -EIO;

	spider_net_write_reg(card, SPIDER_NET_GSINIT,
			     SPIDER_NET_RUN_SEQ_VALUE);

	return 0;
}

/**
 * spider_net_init_firmware - reads in firmware parts
 * @card: card structure
 *
 * Returns 0 on success, <0 on failure
 *
 * spider_net_init_firmware opens the sequencer firmware and does some basic
 * checks. This function opens and releases the firmware structure. A call
 * to download the firmware is performed before the release.
 *
 * Firmware format
 * ===============
 * spider_fw.bin is expected to be a file containing 6*1024*4 bytes, 4k being
 * the program for each sequencer. Use the command
 *    tail -q -n +2 Seq_code1_0x088.txt Seq_code2_0x090.txt              \
 *         Seq_code3_0x098.txt Seq_code4_0x0A0.txt Seq_code5_0x0A8.txt   \
 *         Seq_code6_0x0B0.txt | xxd -r -p -c4 > spider_fw.bin
 *
 * to generate spider_fw.bin, if you have sequencer programs with something
 * like the following contents for each sequencer:
 *    <ONE LINE COMMENT>
 *    <FIRST 4-BYTES-WORD FOR SEQUENCER>
 *    <SECOND 4-BYTES-WORD FOR SEQUENCER>
 *     ...
 *    <1024th 4-BYTES-WORD FOR SEQUENCER>
 */
static int
spider_net_init_firmware(struct spider_net_card *card)
{
	struct firmware *firmware = NULL;
	struct device_node *dn;
	const u8 *fw_prop = NULL;
	int err = -ENOENT;
	int fw_size;

	if (request_firmware((const struct firmware **)&firmware,
			     SPIDER_NET_FIRMWARE_NAME, &card->pdev->dev) == 0) {
		if ( (firmware->size != SPIDER_NET_FIRMWARE_LEN) &&
		     netif_msg_probe(card) ) {
			dev_err(&card->netdev->dev,
			       "Incorrect size of spidernet firmware in " \
			       "filesystem. Looking in host firmware...\n");
			goto try_host_fw;
		}
		err = spider_net_download_firmware(card, firmware->data);

		release_firmware(firmware);
		if (err)
			goto try_host_fw;

		goto done;
	}

try_host_fw:
	dn = pci_device_to_OF_node(card->pdev);
	if (!dn)
		goto out_err;

	fw_prop = of_get_property(dn, "firmware", &fw_size);
	if (!fw_prop)
		goto out_err;

	if ( (fw_size != SPIDER_NET_FIRMWARE_LEN) &&
	     netif_msg_probe(card) ) {
		dev_err(&card->netdev->dev,
		       "Incorrect size of spidernet firmware in host firmware\n");
		goto done;
	}

	err = spider_net_download_firmware(card, fw_prop);

done:
	return err;
out_err:
	if (netif_msg_probe(card))
		dev_err(&card->netdev->dev,
		       "Couldn't find spidernet firmware in filesystem " \
		       "or host firmware\n");
	return err;
}

/**
 * spider_net_open - called upon ifonfig up
 * @netdev: interface device structure
 *
 * returns 0 on success, <0 on failure
 *
 * spider_net_open allocates all the descriptors and memory needed for
 * operation, sets up multicast list and enables interrupts
 */
int
spider_net_open(struct net_device *netdev)
{
	struct spider_net_card *card = netdev_priv(netdev);
	int result;

	result = spider_net_init_firmware(card);
	if (result)
		goto init_firmware_failed;

	/* start probing with copper */
	card->aneg_count = 0;
	card->medium = BCM54XX_COPPER;
	spider_net_setup_aneg(card);
	if (card->phy.def->phy_id)
		mod_timer(&card->aneg_timer, jiffies + SPIDER_NET_ANEG_TIMER);

	result = spider_net_init_chain(card, &card->tx_chain);
	if (result)
		goto alloc_tx_failed;
	card->low_watermark = NULL;

	result = spider_net_init_chain(card, &card->rx_chain);
	if (result)
		goto alloc_rx_failed;

	/* Allocate rx skbs */
	result = spider_net_alloc_rx_skbs(card);
	if (result)
		goto alloc_skbs_failed;

	spider_net_set_multi(netdev);

	/* further enhancement: setup hw vlan, if needed */

	result = -EBUSY;
	if (request_irq(netdev->irq, spider_net_interrupt,
			     IRQF_SHARED, netdev->name, netdev))
		goto register_int_failed;

	spider_net_enable_card(card);

	netif_start_queue(netdev);
	netif_carrier_on(netdev);
	napi_enable(&card->napi);

	spider_net_enable_interrupts(card);

	return 0;

register_int_failed:
	spider_net_free_rx_chain_contents(card);
alloc_skbs_failed:
	spider_net_free_chain(card, &card->rx_chain);
alloc_rx_failed:
	spider_net_free_chain(card, &card->tx_chain);
alloc_tx_failed:
	del_timer_sync(&card->aneg_timer);
init_firmware_failed:
	return result;
}

/**
 * spider_net_link_phy
 * @data: used for pointer to card structure
 *
 */
static void spider_net_link_phy(struct timer_list *t)
{
	struct spider_net_card *card = from_timer(card, t, aneg_timer);
	struct mii_phy *phy = &card->phy;

	/* if link didn't come up after SPIDER_NET_ANEG_TIMEOUT tries, setup phy again */
	if (card->aneg_count > SPIDER_NET_ANEG_TIMEOUT) {

		pr_debug("%s: link is down trying to bring it up\n",
			 card->netdev->name);

		switch (card->medium) {
		case BCM54XX_COPPER:
			/* enable fiber with autonegotiation first */
			if (phy->def->ops->enable_fiber)
				phy->def->ops->enable_fiber(phy, 1);
			card->medium = BCM54XX_FIBER;
			break;

		case BCM54XX_FIBER:
			/* fiber didn't come up, try to disable fiber autoneg */
			if (phy->def->ops->enable_fiber)
				phy->def->ops->enable_fiber(phy, 0);
			card->medium = BCM54XX_UNKNOWN;
			break;

		case BCM54XX_UNKNOWN:
			/* copper, fiber with and without failed,
			 * retry from beginning */
			spider_net_setup_aneg(card);
			card->medium = BCM54XX_COPPER;
			break;
		}

		card->aneg_count = 0;
		mod_timer(&card->aneg_timer, jiffies + SPIDER_NET_ANEG_TIMER);
		return;
	}

	/* link still not up, try again later */
	if (!(phy->def->ops->poll_link(phy))) {
		card->aneg_count++;
		mod_timer(&card->aneg_timer, jiffies + SPIDER_NET_ANEG_TIMER);
		return;
	}

	/* link came up, get abilities */
	phy->def->ops->read_link(phy);

	spider_net_write_reg(card, SPIDER_NET_GMACST,
			     spider_net_read_reg(card, SPIDER_NET_GMACST));
	spider_net_write_reg(card, SPIDER_NET_GMACINTEN, 0x4);

	if (phy->speed == 1000)
		spider_net_write_reg(card, SPIDER_NET_GMACMODE, 0x00000001);
	else
		spider_net_write_reg(card, SPIDER_NET_GMACMODE, 0);

	card->aneg_count = 0;

	pr_info("%s: link up, %i Mbps, %s-duplex %sautoneg.\n",
		card->netdev->name, phy->speed,
		phy->duplex == 1 ? "Full" : "Half",
		phy->autoneg == 1 ? "" : "no ");
}

/**
 * spider_net_setup_phy - setup PHY
 * @card: card structure
 *
 * returns 0 on success, <0 on failure
 *
 * spider_net_setup_phy is used as part of spider_net_probe.
 **/
static int
spider_net_setup_phy(struct spider_net_card *card)
{
	struct mii_phy *phy = &card->phy;

	spider_net_write_reg(card, SPIDER_NET_GDTDMASEL,
			     SPIDER_NET_DMASEL_VALUE);
	spider_net_write_reg(card, SPIDER_NET_GPCCTRL,
			     SPIDER_NET_PHY_CTRL_VALUE);

	phy->dev = card->netdev;
	phy->mdio_read = spider_net_read_phy;
	phy->mdio_write = spider_net_write_phy;

	for (phy->mii_id = 1; phy->mii_id <= 31; phy->mii_id++) {
		unsigned short id;
		id = spider_net_read_phy(card->netdev, phy->mii_id, MII_BMSR);
		if (id != 0x0000 && id != 0xffff) {
			if (!sungem_phy_probe(phy, phy->mii_id)) {
				pr_info("Found %s.\n", phy->def->name);
				break;
			}
		}
	}

	return 0;
}

/**
 * spider_net_workaround_rxramfull - work around firmware bug
 * @card: card structure
 *
 * no return value
 **/
static void
spider_net_workaround_rxramfull(struct spider_net_card *card)
{
	int i, sequencer = 0;

	/* cancel reset */
	spider_net_write_reg(card, SPIDER_NET_CKRCTRL,
			     SPIDER_NET_CKRCTRL_RUN_VALUE);

	/* empty sequencer data */
	for (sequencer = 0; sequencer < SPIDER_NET_FIRMWARE_SEQS;
	     sequencer++) {
		spider_net_write_reg(card, SPIDER_NET_GSnPRGADR +
				     sequencer * 8, 0x0);
		for (i = 0; i < SPIDER_NET_FIRMWARE_SEQWORDS; i++) {
			spider_net_write_reg(card, SPIDER_NET_GSnPRGDAT +
					     sequencer * 8, 0x0);
		}
	}

	/* set sequencer operation */
	spider_net_write_reg(card, SPIDER_NET_GSINIT, 0x000000fe);

	/* reset */
	spider_net_write_reg(card, SPIDER_NET_CKRCTRL,
			     SPIDER_NET_CKRCTRL_STOP_VALUE);
}

/**
 * spider_net_stop - called upon ifconfig down
 * @netdev: interface device structure
 *
 * always returns 0
 */
int
spider_net_stop(struct net_device *netdev)
{
	struct spider_net_card *card = netdev_priv(netdev);

	napi_disable(&card->napi);
	netif_carrier_off(netdev);
	netif_stop_queue(netdev);
	del_timer_sync(&card->tx_timer);
	del_timer_sync(&card->aneg_timer);

	spider_net_disable_interrupts(card);

	free_irq(netdev->irq, netdev);

	spider_net_write_reg(card, SPIDER_NET_GDTDMACCNTR,
			     SPIDER_NET_DMA_TX_FEND_VALUE);

	/* turn off DMA, force end */
	spider_net_disable_rxdmac(card);

	/* release chains */
	spider_net_release_tx_chain(card, 1);
	spider_net_free_rx_chain_contents(card);

	spider_net_free_chain(card, &card->tx_chain);
	spider_net_free_chain(card, &card->rx_chain);

	return 0;
}

/**
 * spider_net_tx_timeout_task - task scheduled by the watchdog timeout
 * function (to be called not under interrupt status)
 * @data: data, is interface device structure
 *
 * called as task when tx hangs, resets interface (if interface is up)
 */
static void
spider_net_tx_timeout_task(struct work_struct *work)
{
	struct spider_net_card *card =
		container_of(work, struct spider_net_card, tx_timeout_task);
	struct net_device *netdev = card->netdev;

	if (!(netdev->flags & IFF_UP))
		goto out;

	netif_device_detach(netdev);
	spider_net_stop(netdev);

	spider_net_workaround_rxramfull(card);
	spider_net_init_card(card);

	if (spider_net_setup_phy(card))
		goto out;

	spider_net_open(netdev);
	spider_net_kick_tx_dma(card);
	netif_device_attach(netdev);

out:
	atomic_dec(&card->tx_timeout_task_counter);
}

/**
 * spider_net_tx_timeout - called when the tx timeout watchdog kicks in.
 * @netdev: interface device structure
 *
 * called, if tx hangs. Schedules a task that resets the interface
 */
static void
spider_net_tx_timeout(struct net_device *netdev)
{
	struct spider_net_card *card;

	card = netdev_priv(netdev);
	atomic_inc(&card->tx_timeout_task_counter);
	if (netdev->flags & IFF_UP)
		schedule_work(&card->tx_timeout_task);
	else
		atomic_dec(&card->tx_timeout_task_counter);
	card->spider_stats.tx_timeouts++;
}

static const struct net_device_ops spider_net_ops = {
	.ndo_open		= spider_net_open,
	.ndo_stop		= spider_net_stop,
	.ndo_start_xmit		= spider_net_xmit,
	.ndo_set_rx_mode	= spider_net_set_multi,
	.ndo_set_mac_address	= spider_net_set_mac,
	.ndo_do_ioctl		= spider_net_do_ioctl,
	.ndo_tx_timeout		= spider_net_tx_timeout,
	.ndo_validate_addr	= eth_validate_addr,
	/* HW VLAN */
#ifdef CONFIG_NET_POLL_CONTROLLER
	/* poll controller */
	.ndo_poll_controller	= spider_net_poll_controller,
#endif /* CONFIG_NET_POLL_CONTROLLER */
};

/**
 * spider_net_setup_netdev_ops - initialization of net_device operations
 * @netdev: net_device structure
 *
 * fills out function pointers in the net_device structure
 */
static void
spider_net_setup_netdev_ops(struct net_device *netdev)
{
	netdev->netdev_ops = &spider_net_ops;
	netdev->watchdog_timeo = SPIDER_NET_WATCHDOG_TIMEOUT;
	/* ethtool ops */
	netdev->ethtool_ops = &spider_net_ethtool_ops;
}

/**
 * spider_net_setup_netdev - initialization of net_device
 * @card: card structure
 *
 * Returns 0 on success or <0 on failure
 *
 * spider_net_setup_netdev initializes the net_device structure
 **/
static int
spider_net_setup_netdev(struct spider_net_card *card)
{
	int result;
	struct net_device *netdev = card->netdev;
	struct device_node *dn;
	struct sockaddr addr;
	const u8 *mac;

	SET_NETDEV_DEV(netdev, &card->pdev->dev);

	pci_set_drvdata(card->pdev, netdev);

	timer_setup(&card->tx_timer, spider_net_cleanup_tx_ring, 0);
	netdev->irq = card->pdev->irq;

	card->aneg_count = 0;
	timer_setup(&card->aneg_timer, spider_net_link_phy, 0);

	netif_napi_add(netdev, &card->napi,
		       spider_net_poll, SPIDER_NET_NAPI_WEIGHT);

	spider_net_setup_netdev_ops(netdev);

	netdev->hw_features = NETIF_F_RXCSUM | NETIF_F_IP_CSUM;
	if (SPIDER_NET_RX_CSUM_DEFAULT)
		netdev->features |= NETIF_F_RXCSUM;
	netdev->features |= NETIF_F_IP_CSUM | NETIF_F_LLTX;
	/* some time: NETIF_F_HW_VLAN_CTAG_TX | NETIF_F_HW_VLAN_CTAG_RX |
	 *		NETIF_F_HW_VLAN_CTAG_FILTER */

	/* MTU range: 64 - 2294 */
	netdev->min_mtu = SPIDER_NET_MIN_MTU;
	netdev->max_mtu = SPIDER_NET_MAX_MTU;

	netdev->irq = card->pdev->irq;
	card->num_rx_ints = 0;
	card->ignore_rx_ramfull = 0;

	dn = pci_device_to_OF_node(card->pdev);
	if (!dn)
		return -EIO;

	mac = of_get_property(dn, "local-mac-address", NULL);
	if (!mac)
		return -EIO;
	memcpy(addr.sa_data, mac, ETH_ALEN);

	result = spider_net_set_mac(netdev, &addr);
	if ((result) && (netif_msg_probe(card)))
		dev_err(&card->netdev->dev,
		        "Failed to set MAC address: %i\n", result);

	result = register_netdev(netdev);
	if (result) {
		if (netif_msg_probe(card))
			dev_err(&card->netdev->dev,
			        "Couldn't register net_device: %i\n", result);
		return result;
	}

	if (netif_msg_probe(card))
		pr_info("Initialized device %s.\n", netdev->name);

	return 0;
}

/**
 * spider_net_alloc_card - allocates net_device and card structure
 *
 * returns the card structure or NULL in case of errors
 *
 * the card and net_device structures are linked to each other
 */
static struct spider_net_card *
spider_net_alloc_card(void)
{
	struct net_device *netdev;
	struct spider_net_card *card;
	size_t alloc_size;

	alloc_size = sizeof(struct spider_net_card) +
	   (tx_descriptors + rx_descriptors) * sizeof(struct spider_net_descr);
	netdev = alloc_etherdev(alloc_size);
	if (!netdev)
		return NULL;

	card = netdev_priv(netdev);
	card->netdev = netdev;
	card->msg_enable = SPIDER_NET_DEFAULT_MSG;
	INIT_WORK(&card->tx_timeout_task, spider_net_tx_timeout_task);
	init_waitqueue_head(&card->waitq);
	atomic_set(&card->tx_timeout_task_counter, 0);

	card->rx_chain.num_desc = rx_descriptors;
	card->rx_chain.ring = card->darray;
	card->tx_chain.num_desc = tx_descriptors;
	card->tx_chain.ring = card->darray + rx_descriptors;

	return card;
}

/**
 * spider_net_undo_pci_setup - releases PCI ressources
 * @card: card structure
 *
 * spider_net_undo_pci_setup releases the mapped regions
 */
static void
spider_net_undo_pci_setup(struct spider_net_card *card)
{
	iounmap(card->regs);
	pci_release_regions(card->pdev);
}

/**
 * spider_net_setup_pci_dev - sets up the device in terms of PCI operations
 * @pdev: PCI device
 *
 * Returns the card structure or NULL if any errors occur
 *
 * spider_net_setup_pci_dev initializes pdev and together with the
 * functions called in spider_net_open configures the device so that
 * data can be transferred over it
 * The net_device structure is attached to the card structure, if the
 * function returns without error.
 **/
static struct spider_net_card *
spider_net_setup_pci_dev(struct pci_dev *pdev)
{
	struct spider_net_card *card;
	unsigned long mmio_start, mmio_len;

	if (pci_enable_device(pdev)) {
		dev_err(&pdev->dev, "Couldn't enable PCI device\n");
		return NULL;
	}

	if (!(pci_resource_flags(pdev, 0) & IORESOURCE_MEM)) {
		dev_err(&pdev->dev,
		        "Couldn't find proper PCI device base address.\n");
		goto out_disable_dev;
	}

	if (pci_request_regions(pdev, spider_net_driver_name)) {
		dev_err(&pdev->dev,
		        "Couldn't obtain PCI resources, aborting.\n");
		goto out_disable_dev;
	}

	pci_set_master(pdev);

	card = spider_net_alloc_card();
	if (!card) {
		dev_err(&pdev->dev,
		        "Couldn't allocate net_device structure, aborting.\n");
		goto out_release_regions;
	}
	card->pdev = pdev;

	/* fetch base address and length of first resource */
	mmio_start = pci_resource_start(pdev, 0);
	mmio_len = pci_resource_len(pdev, 0);

	card->netdev->mem_start = mmio_start;
	card->netdev->mem_end = mmio_start + mmio_len;
	card->regs = ioremap(mmio_start, mmio_len);

	if (!card->regs) {
		dev_err(&pdev->dev,
		        "Couldn't obtain PCI resources, aborting.\n");
		goto out_release_regions;
	}

	return card;

out_release_regions:
	pci_release_regions(pdev);
out_disable_dev:
	pci_disable_device(pdev);
	return NULL;
}

/**
 * spider_net_probe - initialization of a device
 * @pdev: PCI device
 * @ent: entry in the device id list
 *
 * Returns 0 on success, <0 on failure
 *
 * spider_net_probe initializes pdev and registers a net_device
 * structure for it. After that, the device can be ifconfig'ed up
 **/
static int
spider_net_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
{
	int err = -EIO;
	struct spider_net_card *card;

	card = spider_net_setup_pci_dev(pdev);
	if (!card)
		goto out;

	spider_net_workaround_rxramfull(card);
	spider_net_init_card(card);

	err = spider_net_setup_phy(card);
	if (err)
		goto out_undo_pci;

	err = spider_net_setup_netdev(card);
	if (err)
		goto out_undo_pci;

	return 0;

out_undo_pci:
	spider_net_undo_pci_setup(card);
	free_netdev(card->netdev);
out:
	return err;
}

/**
 * spider_net_remove - removal of a device
 * @pdev: PCI device
 *
 * Returns 0 on success, <0 on failure
 *
 * spider_net_remove is called to remove the device and unregisters the
 * net_device
 **/
static void
spider_net_remove(struct pci_dev *pdev)
{
	struct net_device *netdev;
	struct spider_net_card *card;

	netdev = pci_get_drvdata(pdev);
	card = netdev_priv(netdev);

	wait_event(card->waitq,
		   atomic_read(&card->tx_timeout_task_counter) == 0);

	unregister_netdev(netdev);

	/* switch off card */
	spider_net_write_reg(card, SPIDER_NET_CKRCTRL,
			     SPIDER_NET_CKRCTRL_STOP_VALUE);
	spider_net_write_reg(card, SPIDER_NET_CKRCTRL,
			     SPIDER_NET_CKRCTRL_RUN_VALUE);

	spider_net_undo_pci_setup(card);
	free_netdev(netdev);
}

static struct pci_driver spider_net_driver = {
	.name		= spider_net_driver_name,
	.id_table	= spider_net_pci_tbl,
	.probe		= spider_net_probe,
	.remove		= spider_net_remove
};

/**
 * spider_net_init - init function when the driver is loaded
 *
 * spider_net_init registers the device driver
 */
static int __init spider_net_init(void)
{
	printk(KERN_INFO "Spidernet version %s.\n", VERSION);

	if (rx_descriptors < SPIDER_NET_RX_DESCRIPTORS_MIN) {
		rx_descriptors = SPIDER_NET_RX_DESCRIPTORS_MIN;
		pr_info("adjusting rx descriptors to %i.\n", rx_descriptors);
	}
	if (rx_descriptors > SPIDER_NET_RX_DESCRIPTORS_MAX) {
		rx_descriptors = SPIDER_NET_RX_DESCRIPTORS_MAX;
		pr_info("adjusting rx descriptors to %i.\n", rx_descriptors);
	}
	if (tx_descriptors < SPIDER_NET_TX_DESCRIPTORS_MIN) {
		tx_descriptors = SPIDER_NET_TX_DESCRIPTORS_MIN;
		pr_info("adjusting tx descriptors to %i.\n", tx_descriptors);
	}
	if (tx_descriptors > SPIDER_NET_TX_DESCRIPTORS_MAX) {
		tx_descriptors = SPIDER_NET_TX_DESCRIPTORS_MAX;
		pr_info("adjusting tx descriptors to %i.\n", tx_descriptors);
	}

	return pci_register_driver(&spider_net_driver);
}

/**
 * spider_net_cleanup - exit function when driver is unloaded
 *
 * spider_net_cleanup unregisters the device driver
 */
static void __exit spider_net_cleanup(void)
{
	pci_unregister_driver(&spider_net_driver);
}

module_init(spider_net_init);
module_exit(spider_net_cleanup);