summaryrefslogtreecommitdiffstats
path: root/drivers/net/ethernet/micrel/ks8695net.c
blob: b6c60fdef4ff6d1d5498e1bfb688b4edfa7ad8bd (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
/*
 * Micrel KS8695 (Centaur) Ethernet.
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License as
 * published by the Free Software Foundation; either version 2 of the
 * License, or (at your option) any later version.
 *
 * 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.
 *
 * Copyright 2008 Simtec Electronics
 *		  Daniel Silverstone <dsilvers@simtec.co.uk>
 *		  Vincent Sanders <vince@simtec.co.uk>
 */

#include <linux/dma-mapping.h>
#include <linux/module.h>
#include <linux/ioport.h>
#include <linux/netdevice.h>
#include <linux/etherdevice.h>
#include <linux/init.h>
#include <linux/interrupt.h>
#include <linux/skbuff.h>
#include <linux/spinlock.h>
#include <linux/crc32.h>
#include <linux/mii.h>
#include <linux/ethtool.h>
#include <linux/delay.h>
#include <linux/platform_device.h>
#include <linux/irq.h>
#include <linux/io.h>
#include <linux/slab.h>

#include <asm/irq.h>

#include <mach/regs-switch.h>
#include <mach/regs-misc.h>
#include <asm/mach/irq.h>
#include <mach/regs-irq.h>

#include "ks8695net.h"

#define MODULENAME	"ks8695_ether"
#define MODULEVERSION	"1.02"

/*
 * Transmit and device reset timeout, default 5 seconds.
 */
static int watchdog = 5000;

/* Hardware structures */

/**
 *	struct rx_ring_desc - Receive descriptor ring element
 *	@status: The status of the descriptor element (E.g. who owns it)
 *	@length: The number of bytes in the block pointed to by data_ptr
 *	@data_ptr: The physical address of the data block to receive into
 *	@next_desc: The physical address of the next descriptor element.
 */
struct rx_ring_desc {
	__le32	status;
	__le32	length;
	__le32	data_ptr;
	__le32	next_desc;
};

/**
 *	struct tx_ring_desc - Transmit descriptor ring element
 *	@owner: Who owns the descriptor
 *	@status: The number of bytes in the block pointed to by data_ptr
 *	@data_ptr: The physical address of the data block to receive into
 *	@next_desc: The physical address of the next descriptor element.
 */
struct tx_ring_desc {
	__le32	owner;
	__le32	status;
	__le32	data_ptr;
	__le32	next_desc;
};

/**
 *	struct ks8695_skbuff - sk_buff wrapper for rx/tx rings.
 *	@skb: The buffer in the ring
 *	@dma_ptr: The mapped DMA pointer of the buffer
 *	@length: The number of bytes mapped to dma_ptr
 */
struct ks8695_skbuff {
	struct sk_buff	*skb;
	dma_addr_t	dma_ptr;
	u32		length;
};

/* Private device structure */

#define MAX_TX_DESC 8
#define MAX_TX_DESC_MASK 0x7
#define MAX_RX_DESC 16
#define MAX_RX_DESC_MASK 0xf

/*napi_weight have better more than rx DMA buffers*/
#define NAPI_WEIGHT   64

#define MAX_RXBUF_SIZE 0x700

#define TX_RING_DMA_SIZE (sizeof(struct tx_ring_desc) * MAX_TX_DESC)
#define RX_RING_DMA_SIZE (sizeof(struct rx_ring_desc) * MAX_RX_DESC)
#define RING_DMA_SIZE (TX_RING_DMA_SIZE + RX_RING_DMA_SIZE)

/**
 *	enum ks8695_dtype - Device type
 *	@KS8695_DTYPE_WAN: This device is a WAN interface
 *	@KS8695_DTYPE_LAN: This device is a LAN interface
 *	@KS8695_DTYPE_HPNA: This device is an HPNA interface
 */
enum ks8695_dtype {
	KS8695_DTYPE_WAN,
	KS8695_DTYPE_LAN,
	KS8695_DTYPE_HPNA,
};

/**
 *	struct ks8695_priv - Private data for the KS8695 Ethernet
 *	@in_suspend: Flag to indicate if we're suspending/resuming
 *	@ndev: The net_device for this interface
 *	@dev: The platform device object for this interface
 *	@dtype: The type of this device
 *	@io_regs: The ioremapped registers for this interface
 *      @napi : Add support NAPI for Rx
 *	@rx_irq_name: The textual name of the RX IRQ from the platform data
 *	@tx_irq_name: The textual name of the TX IRQ from the platform data
 *	@link_irq_name: The textual name of the link IRQ from the
 *			platform data if available
 *	@rx_irq: The IRQ number for the RX IRQ
 *	@tx_irq: The IRQ number for the TX IRQ
 *	@link_irq: The IRQ number for the link IRQ if available
 *	@regs_req: The resource request for the registers region
 *	@phyiface_req: The resource request for the phy/switch region
 *		       if available
 *	@phyiface_regs: The ioremapped registers for the phy/switch if available
 *	@ring_base: The base pointer of the dma coherent memory for the rings
 *	@ring_base_dma: The DMA mapped equivalent of ring_base
 *	@tx_ring: The pointer in ring_base of the TX ring
 *	@tx_ring_used: The number of slots in the TX ring which are occupied
 *	@tx_ring_next_slot: The next slot to fill in the TX ring
 *	@tx_ring_dma: The DMA mapped equivalent of tx_ring
 *	@tx_buffers: The sk_buff mappings for the TX ring
 *	@txq_lock: A lock to protect the tx_buffers tx_ring_used etc variables
 *	@rx_ring: The pointer in ring_base of the RX ring
 *	@rx_ring_dma: The DMA mapped equivalent of rx_ring
 *	@rx_buffers: The sk_buff mappings for the RX ring
 *	@next_rx_desc_read: The next RX descriptor to read from on IRQ
 *      @rx_lock: A lock to protect Rx irq function
 *	@msg_enable: The flags for which messages to emit
 */
struct ks8695_priv {
	int in_suspend;
	struct net_device *ndev;
	struct device *dev;
	enum ks8695_dtype dtype;
	void __iomem *io_regs;

	struct napi_struct	napi;

	const char *rx_irq_name, *tx_irq_name, *link_irq_name;
	int rx_irq, tx_irq, link_irq;

	struct resource *regs_req, *phyiface_req;
	void __iomem *phyiface_regs;

	void *ring_base;
	dma_addr_t ring_base_dma;

	struct tx_ring_desc *tx_ring;
	int tx_ring_used;
	int tx_ring_next_slot;
	dma_addr_t tx_ring_dma;
	struct ks8695_skbuff tx_buffers[MAX_TX_DESC];
	spinlock_t txq_lock;

	struct rx_ring_desc *rx_ring;
	dma_addr_t rx_ring_dma;
	struct ks8695_skbuff rx_buffers[MAX_RX_DESC];
	int next_rx_desc_read;
	spinlock_t rx_lock;

	int msg_enable;
};

/* Register access */

/**
 *	ks8695_readreg - Read from a KS8695 ethernet register
 *	@ksp: The device to read from
 *	@reg: The register to read
 */
static inline u32
ks8695_readreg(struct ks8695_priv *ksp, int reg)
{
	return readl(ksp->io_regs + reg);
}

/**
 *	ks8695_writereg - Write to a KS8695 ethernet register
 *	@ksp: The device to write to
 *	@reg: The register to write
 *	@value: The value to write to the register
 */
static inline void
ks8695_writereg(struct ks8695_priv *ksp, int reg, u32 value)
{
	writel(value, ksp->io_regs + reg);
}

/* Utility functions */

/**
 *	ks8695_port_type - Retrieve port-type as user-friendly string
 *	@ksp: The device to return the type for
 *
 *	Returns a string indicating which of the WAN, LAN or HPNA
 *	ports this device is likely to represent.
 */
static const char *
ks8695_port_type(struct ks8695_priv *ksp)
{
	switch (ksp->dtype) {
	case KS8695_DTYPE_LAN:
		return "LAN";
	case KS8695_DTYPE_WAN:
		return "WAN";
	case KS8695_DTYPE_HPNA:
		return "HPNA";
	}

	return "UNKNOWN";
}

/**
 *	ks8695_update_mac - Update the MAC registers in the device
 *	@ksp: The device to update
 *
 *	Updates the MAC registers in the KS8695 device from the address in the
 *	net_device structure associated with this interface.
 */
static void
ks8695_update_mac(struct ks8695_priv *ksp)
{
	/* Update the HW with the MAC from the net_device */
	struct net_device *ndev = ksp->ndev;
	u32 machigh, maclow;

	maclow	= ((ndev->dev_addr[2] << 24) | (ndev->dev_addr[3] << 16) |
		   (ndev->dev_addr[4] <<  8) | (ndev->dev_addr[5] <<  0));
	machigh = ((ndev->dev_addr[0] <<  8) | (ndev->dev_addr[1] <<  0));

	ks8695_writereg(ksp, KS8695_MAL, maclow);
	ks8695_writereg(ksp, KS8695_MAH, machigh);

}

/**
 *	ks8695_refill_rxbuffers - Re-fill the RX buffer ring
 *	@ksp: The device to refill
 *
 *	Iterates the RX ring of the device looking for empty slots.
 *	For each empty slot, we allocate and map a new SKB and give it
 *	to the hardware.
 *	This can be called from interrupt context safely.
 */
static void
ks8695_refill_rxbuffers(struct ks8695_priv *ksp)
{
	/* Run around the RX ring, filling in any missing sk_buff's */
	int buff_n;

	for (buff_n = 0; buff_n < MAX_RX_DESC; ++buff_n) {
		if (!ksp->rx_buffers[buff_n].skb) {
			struct sk_buff *skb =
				netdev_alloc_skb(ksp->ndev, MAX_RXBUF_SIZE);
			dma_addr_t mapping;

			ksp->rx_buffers[buff_n].skb = skb;
			if (skb == NULL) {
				/* Failed to allocate one, perhaps
				 * we'll try again later.
				 */
				break;
			}

			mapping = dma_map_single(ksp->dev, skb->data,
						 MAX_RXBUF_SIZE,
						 DMA_FROM_DEVICE);
			if (unlikely(dma_mapping_error(ksp->dev, mapping))) {
				/* Failed to DMA map this SKB, try later */
				dev_kfree_skb_irq(skb);
				ksp->rx_buffers[buff_n].skb = NULL;
				break;
			}
			ksp->rx_buffers[buff_n].dma_ptr = mapping;
			ksp->rx_buffers[buff_n].length = MAX_RXBUF_SIZE;

			/* Record this into the DMA ring */
			ksp->rx_ring[buff_n].data_ptr = cpu_to_le32(mapping);
			ksp->rx_ring[buff_n].length =
				cpu_to_le32(MAX_RXBUF_SIZE);

			wmb();

			/* And give ownership over to the hardware */
			ksp->rx_ring[buff_n].status = cpu_to_le32(RDES_OWN);
		}
	}
}

/* Maximum number of multicast addresses which the KS8695 HW supports */
#define KS8695_NR_ADDRESSES	16

/**
 *	ks8695_init_partial_multicast - Init the mcast addr registers
 *	@ksp: The device to initialise
 *	@addr: The multicast address list to use
 *	@nr_addr: The number of addresses in the list
 *
 *	This routine is a helper for ks8695_set_multicast - it writes
 *	the additional-address registers in the KS8695 ethernet device
 *	and cleans up any others left behind.
 */
static void
ks8695_init_partial_multicast(struct ks8695_priv *ksp,
			      struct net_device *ndev)
{
	u32 low, high;
	int i;
	struct netdev_hw_addr *ha;

	i = 0;
	netdev_for_each_mc_addr(ha, ndev) {
		/* Ran out of space in chip? */
		BUG_ON(i == KS8695_NR_ADDRESSES);

		low = (ha->addr[2] << 24) | (ha->addr[3] << 16) |
		      (ha->addr[4] << 8) | (ha->addr[5]);
		high = (ha->addr[0] << 8) | (ha->addr[1]);

		ks8695_writereg(ksp, KS8695_AAL_(i), low);
		ks8695_writereg(ksp, KS8695_AAH_(i), AAH_E | high);
		i++;
	}

	/* Clear the remaining Additional Station Addresses */
	for (; i < KS8695_NR_ADDRESSES; i++) {
		ks8695_writereg(ksp, KS8695_AAL_(i), 0);
		ks8695_writereg(ksp, KS8695_AAH_(i), 0);
	}
}

/* Interrupt handling */

/**
 *	ks8695_tx_irq - Transmit IRQ handler
 *	@irq: The IRQ which went off (ignored)
 *	@dev_id: The net_device for the interrupt
 *
 *	Process the TX ring, clearing out any transmitted slots.
 *	Allows the net_device to pass us new packets once slots are
 *	freed.
 */
static irqreturn_t
ks8695_tx_irq(int irq, void *dev_id)
{
	struct net_device *ndev = (struct net_device *)dev_id;
	struct ks8695_priv *ksp = netdev_priv(ndev);
	int buff_n;

	for (buff_n = 0; buff_n < MAX_TX_DESC; ++buff_n) {
		if (ksp->tx_buffers[buff_n].skb &&
		    !(ksp->tx_ring[buff_n].owner & cpu_to_le32(TDES_OWN))) {
			rmb();
			/* An SKB which is not owned by HW is present */
			/* Update the stats for the net_device */
			ndev->stats.tx_packets++;
			ndev->stats.tx_bytes += ksp->tx_buffers[buff_n].length;

			/* Free the packet from the ring */
			ksp->tx_ring[buff_n].data_ptr = 0;

			/* Free the sk_buff */
			dma_unmap_single(ksp->dev,
					 ksp->tx_buffers[buff_n].dma_ptr,
					 ksp->tx_buffers[buff_n].length,
					 DMA_TO_DEVICE);
			dev_kfree_skb_irq(ksp->tx_buffers[buff_n].skb);
			ksp->tx_buffers[buff_n].skb = NULL;
			ksp->tx_ring_used--;
		}
	}

	netif_wake_queue(ndev);

	return IRQ_HANDLED;
}

/**
 *	ks8695_get_rx_enable_bit - Get rx interrupt enable/status bit
 *	@ksp: Private data for the KS8695 Ethernet
 *
 *    For KS8695 document:
 *    Interrupt Enable Register (offset 0xE204)
 *        Bit29 : WAN MAC Receive Interrupt Enable
 *        Bit16 : LAN MAC Receive Interrupt Enable
 *    Interrupt Status Register (Offset 0xF208)
 *        Bit29: WAN MAC Receive Status
 *        Bit16: LAN MAC Receive Status
 *    So, this Rx interrupt enable/status bit number is equal
 *    as Rx IRQ number.
 */
static inline u32 ks8695_get_rx_enable_bit(struct ks8695_priv *ksp)
{
	return ksp->rx_irq;
}

/**
 *	ks8695_rx_irq - Receive IRQ handler
 *	@irq: The IRQ which went off (ignored)
 *	@dev_id: The net_device for the interrupt
 *
 *	Inform NAPI that packet reception needs to be scheduled
 */

static irqreturn_t
ks8695_rx_irq(int irq, void *dev_id)
{
	struct net_device *ndev = (struct net_device *)dev_id;
	struct ks8695_priv *ksp = netdev_priv(ndev);

	spin_lock(&ksp->rx_lock);

	if (napi_schedule_prep(&ksp->napi)) {
		unsigned long status = readl(KS8695_IRQ_VA + KS8695_INTEN);
		unsigned long mask_bit = 1 << ks8695_get_rx_enable_bit(ksp);
		/*disable rx interrupt*/
		status &= ~mask_bit;
		writel(status , KS8695_IRQ_VA + KS8695_INTEN);
		__napi_schedule(&ksp->napi);
	}

	spin_unlock(&ksp->rx_lock);
	return IRQ_HANDLED;
}

/**
 *	ks8695_rx - Receive packets called by NAPI poll method
 *	@ksp: Private data for the KS8695 Ethernet
 *	@budget: Number of packets allowed to process
 */
static int ks8695_rx(struct ks8695_priv *ksp, int budget)
{
	struct net_device *ndev = ksp->ndev;
	struct sk_buff *skb;
	int buff_n;
	u32 flags;
	int pktlen;
	int received = 0;

	buff_n = ksp->next_rx_desc_read;
	while (received < budget
			&& ksp->rx_buffers[buff_n].skb
			&& (!(ksp->rx_ring[buff_n].status &
					cpu_to_le32(RDES_OWN)))) {
			rmb();
			flags = le32_to_cpu(ksp->rx_ring[buff_n].status);

			/* Found an SKB which we own, this means we
			 * received a packet
			 */
			if ((flags & (RDES_FS | RDES_LS)) !=
			    (RDES_FS | RDES_LS)) {
				/* This packet is not the first and
				 * the last segment.  Therefore it is
				 * a "spanning" packet and we can't
				 * handle it
				 */
				goto rx_failure;
			}

			if (flags & (RDES_ES | RDES_RE)) {
				/* It's an error packet */
				ndev->stats.rx_errors++;
				if (flags & RDES_TL)
					ndev->stats.rx_length_errors++;
				if (flags & RDES_RF)
					ndev->stats.rx_length_errors++;
				if (flags & RDES_CE)
					ndev->stats.rx_crc_errors++;
				if (flags & RDES_RE)
					ndev->stats.rx_missed_errors++;

				goto rx_failure;
			}

			pktlen = flags & RDES_FLEN;
			pktlen -= 4; /* Drop the CRC */

			/* Retrieve the sk_buff */
			skb = ksp->rx_buffers[buff_n].skb;

			/* Clear it from the ring */
			ksp->rx_buffers[buff_n].skb = NULL;
			ksp->rx_ring[buff_n].data_ptr = 0;

			/* Unmap the SKB */
			dma_unmap_single(ksp->dev,
					 ksp->rx_buffers[buff_n].dma_ptr,
					 ksp->rx_buffers[buff_n].length,
					 DMA_FROM_DEVICE);

			/* Relinquish the SKB to the network layer */
			skb_put(skb, pktlen);
			skb->protocol = eth_type_trans(skb, ndev);
			netif_receive_skb(skb);

			/* Record stats */
			ndev->stats.rx_packets++;
			ndev->stats.rx_bytes += pktlen;
			goto rx_finished;

rx_failure:
			/* This ring entry is an error, but we can
			 * re-use the skb
			 */
			/* Give the ring entry back to the hardware */
			ksp->rx_ring[buff_n].status = cpu_to_le32(RDES_OWN);
rx_finished:
			received++;
			buff_n = (buff_n + 1) & MAX_RX_DESC_MASK;
	}

	/* And note which RX descriptor we last did */
	ksp->next_rx_desc_read = buff_n;

	/* And refill the buffers */
	ks8695_refill_rxbuffers(ksp);

	/* Kick the RX DMA engine, in case it became suspended */
	ks8695_writereg(ksp, KS8695_DRSC, 0);

	return received;
}


/**
 *	ks8695_poll - Receive packet by NAPI poll method
 *	@ksp: Private data for the KS8695 Ethernet
 *	@budget: The remaining number packets for network subsystem
 *
 *     Invoked by the network core when it requests for new
 *     packets from the driver
 */
static int ks8695_poll(struct napi_struct *napi, int budget)
{
	struct ks8695_priv *ksp = container_of(napi, struct ks8695_priv, napi);
	unsigned long  work_done;

	unsigned long isr = readl(KS8695_IRQ_VA + KS8695_INTEN);
	unsigned long mask_bit = 1 << ks8695_get_rx_enable_bit(ksp);

	work_done = ks8695_rx(ksp, budget);

	if (work_done < budget) {
		unsigned long flags;
		spin_lock_irqsave(&ksp->rx_lock, flags);
		__napi_complete(napi);
		/*enable rx interrupt*/
		writel(isr | mask_bit, KS8695_IRQ_VA + KS8695_INTEN);
		spin_unlock_irqrestore(&ksp->rx_lock, flags);
	}
	return work_done;
}

/**
 *	ks8695_link_irq - Link change IRQ handler
 *	@irq: The IRQ which went off (ignored)
 *	@dev_id: The net_device for the interrupt
 *
 *	The WAN interface can generate an IRQ when the link changes,
 *	report this to the net layer and the user.
 */
static irqreturn_t
ks8695_link_irq(int irq, void *dev_id)
{
	struct net_device *ndev = (struct net_device *)dev_id;
	struct ks8695_priv *ksp = netdev_priv(ndev);
	u32 ctrl;

	ctrl = readl(ksp->phyiface_regs + KS8695_WMC);
	if (ctrl & WMC_WLS) {
		netif_carrier_on(ndev);
		if (netif_msg_link(ksp))
			dev_info(ksp->dev,
				 "%s: Link is now up (10%sMbps/%s-duplex)\n",
				 ndev->name,
				 (ctrl & WMC_WSS) ? "0" : "",
				 (ctrl & WMC_WDS) ? "Full" : "Half");
	} else {
		netif_carrier_off(ndev);
		if (netif_msg_link(ksp))
			dev_info(ksp->dev, "%s: Link is now down.\n",
				 ndev->name);
	}

	return IRQ_HANDLED;
}


/* KS8695 Device functions */

/**
 *	ks8695_reset - Reset a KS8695 ethernet interface
 *	@ksp: The interface to reset
 *
 *	Perform an engine reset of the interface and re-program it
 *	with sensible defaults.
 */
static void
ks8695_reset(struct ks8695_priv *ksp)
{
	int reset_timeout = watchdog;
	/* Issue the reset via the TX DMA control register */
	ks8695_writereg(ksp, KS8695_DTXC, DTXC_TRST);
	while (reset_timeout--) {
		if (!(ks8695_readreg(ksp, KS8695_DTXC) & DTXC_TRST))
			break;
		msleep(1);
	}

	if (reset_timeout < 0) {
		dev_crit(ksp->dev,
			 "Timeout waiting for DMA engines to reset\n");
		/* And blithely carry on */
	}

	/* Definitely wait long enough before attempting to program
	 * the engines
	 */
	msleep(10);

	/* RX: unicast and broadcast */
	ks8695_writereg(ksp, KS8695_DRXC, DRXC_RU | DRXC_RB);
	/* TX: pad and add CRC */
	ks8695_writereg(ksp, KS8695_DTXC, DTXC_TEP | DTXC_TAC);
}

/**
 *	ks8695_shutdown - Shut down a KS8695 ethernet interface
 *	@ksp: The interface to shut down
 *
 *	This disables packet RX/TX, cleans up IRQs, drains the rings,
 *	and basically places the interface into a clean shutdown
 *	state.
 */
static void
ks8695_shutdown(struct ks8695_priv *ksp)
{
	u32 ctrl;
	int buff_n;

	/* Disable packet transmission */
	ctrl = ks8695_readreg(ksp, KS8695_DTXC);
	ks8695_writereg(ksp, KS8695_DTXC, ctrl & ~DTXC_TE);

	/* Disable packet reception */
	ctrl = ks8695_readreg(ksp, KS8695_DRXC);
	ks8695_writereg(ksp, KS8695_DRXC, ctrl & ~DRXC_RE);

	/* Release the IRQs */
	free_irq(ksp->rx_irq, ksp->ndev);
	free_irq(ksp->tx_irq, ksp->ndev);
	if (ksp->link_irq != -1)
		free_irq(ksp->link_irq, ksp->ndev);

	/* Throw away any pending TX packets */
	for (buff_n = 0; buff_n < MAX_TX_DESC; ++buff_n) {
		if (ksp->tx_buffers[buff_n].skb) {
			/* Remove this SKB from the TX ring */
			ksp->tx_ring[buff_n].owner = 0;
			ksp->tx_ring[buff_n].status = 0;
			ksp->tx_ring[buff_n].data_ptr = 0;

			/* Unmap and bin this SKB */
			dma_unmap_single(ksp->dev,
					 ksp->tx_buffers[buff_n].dma_ptr,
					 ksp->tx_buffers[buff_n].length,
					 DMA_TO_DEVICE);
			dev_kfree_skb_irq(ksp->tx_buffers[buff_n].skb);
			ksp->tx_buffers[buff_n].skb = NULL;
		}
	}

	/* Purge the RX buffers */
	for (buff_n = 0; buff_n < MAX_RX_DESC; ++buff_n) {
		if (ksp->rx_buffers[buff_n].skb) {
			/* Remove the SKB from the RX ring */
			ksp->rx_ring[buff_n].status = 0;
			ksp->rx_ring[buff_n].data_ptr = 0;

			/* Unmap and bin the SKB */
			dma_unmap_single(ksp->dev,
					 ksp->rx_buffers[buff_n].dma_ptr,
					 ksp->rx_buffers[buff_n].length,
					 DMA_FROM_DEVICE);
			dev_kfree_skb_irq(ksp->rx_buffers[buff_n].skb);
			ksp->rx_buffers[buff_n].skb = NULL;
		}
	}
}


/**
 *	ks8695_setup_irq - IRQ setup helper function
 *	@irq: The IRQ number to claim
 *	@irq_name: The name to give the IRQ claimant
 *	@handler: The function to call to handle the IRQ
 *	@ndev: The net_device to pass in as the dev_id argument to the handler
 *
 *	Return 0 on success.
 */
static int
ks8695_setup_irq(int irq, const char *irq_name,
		 irq_handler_t handler, struct net_device *ndev)
{
	int ret;

	ret = request_irq(irq, handler, IRQF_SHARED, irq_name, ndev);

	if (ret) {
		dev_err(&ndev->dev, "failure to request IRQ %d\n", irq);
		return ret;
	}

	return 0;
}

/**
 *	ks8695_init_net - Initialise a KS8695 ethernet interface
 *	@ksp: The interface to initialise
 *
 *	This routine fills the RX ring, initialises the DMA engines,
 *	allocates the IRQs and then starts the packet TX and RX
 *	engines.
 */
static int
ks8695_init_net(struct ks8695_priv *ksp)
{
	int ret;
	u32 ctrl;

	ks8695_refill_rxbuffers(ksp);

	/* Initialise the DMA engines */
	ks8695_writereg(ksp, KS8695_RDLB, (u32) ksp->rx_ring_dma);
	ks8695_writereg(ksp, KS8695_TDLB, (u32) ksp->tx_ring_dma);

	/* Request the IRQs */
	ret = ks8695_setup_irq(ksp->rx_irq, ksp->rx_irq_name,
			       ks8695_rx_irq, ksp->ndev);
	if (ret)
		return ret;
	ret = ks8695_setup_irq(ksp->tx_irq, ksp->tx_irq_name,
			       ks8695_tx_irq, ksp->ndev);
	if (ret)
		return ret;
	if (ksp->link_irq != -1) {
		ret = ks8695_setup_irq(ksp->link_irq, ksp->link_irq_name,
				       ks8695_link_irq, ksp->ndev);
		if (ret)
			return ret;
	}

	/* Set up the ring indices */
	ksp->next_rx_desc_read = 0;
	ksp->tx_ring_next_slot = 0;
	ksp->tx_ring_used = 0;

	/* Bring up transmission */
	ctrl = ks8695_readreg(ksp, KS8695_DTXC);
	/* Enable packet transmission */
	ks8695_writereg(ksp, KS8695_DTXC, ctrl | DTXC_TE);

	/* Bring up the reception */
	ctrl = ks8695_readreg(ksp, KS8695_DRXC);
	/* Enable packet reception */
	ks8695_writereg(ksp, KS8695_DRXC, ctrl | DRXC_RE);
	/* And start the DMA engine */
	ks8695_writereg(ksp, KS8695_DRSC, 0);

	/* All done */
	return 0;
}

/**
 *	ks8695_release_device - HW resource release for KS8695 e-net
 *	@ksp: The device to be freed
 *
 *	This unallocates io memory regions, dma-coherent regions etc
 *	which were allocated in ks8695_probe.
 */
static void
ks8695_release_device(struct ks8695_priv *ksp)
{
	/* Unmap the registers */
	iounmap(ksp->io_regs);
	if (ksp->phyiface_regs)
		iounmap(ksp->phyiface_regs);

	/* And release the request */
	release_resource(ksp->regs_req);
	kfree(ksp->regs_req);
	if (ksp->phyiface_req) {
		release_resource(ksp->phyiface_req);
		kfree(ksp->phyiface_req);
	}

	/* Free the ring buffers */
	dma_free_coherent(ksp->dev, RING_DMA_SIZE,
			  ksp->ring_base, ksp->ring_base_dma);
}

/* Ethtool support */

/**
 *	ks8695_get_msglevel - Get the messages enabled for emission
 *	@ndev: The network device to read from
 */
static u32
ks8695_get_msglevel(struct net_device *ndev)
{
	struct ks8695_priv *ksp = netdev_priv(ndev);

	return ksp->msg_enable;
}

/**
 *	ks8695_set_msglevel - Set the messages enabled for emission
 *	@ndev: The network device to configure
 *	@value: The messages to set for emission
 */
static void
ks8695_set_msglevel(struct net_device *ndev, u32 value)
{
	struct ks8695_priv *ksp = netdev_priv(ndev);

	ksp->msg_enable = value;
}

/**
 *	ks8695_wan_get_settings - Get device-specific settings.
 *	@ndev: The network device to read settings from
 *	@cmd: The ethtool structure to read into
 */
static int
ks8695_wan_get_settings(struct net_device *ndev, struct ethtool_cmd *cmd)
{
	struct ks8695_priv *ksp = netdev_priv(ndev);
	u32 ctrl;

	/* All ports on the KS8695 support these... */
	cmd->supported = (SUPPORTED_10baseT_Half | SUPPORTED_10baseT_Full |
			  SUPPORTED_100baseT_Half | SUPPORTED_100baseT_Full |
			  SUPPORTED_TP | SUPPORTED_MII);
	cmd->transceiver = XCVR_INTERNAL;

	cmd->advertising = ADVERTISED_TP | ADVERTISED_MII;
	cmd->port = PORT_MII;
	cmd->supported |= (SUPPORTED_Autoneg | SUPPORTED_Pause);
	cmd->phy_address = 0;

	ctrl = readl(ksp->phyiface_regs + KS8695_WMC);
	if ((ctrl & WMC_WAND) == 0) {
		/* auto-negotiation is enabled */
		cmd->advertising |= ADVERTISED_Autoneg;
		if (ctrl & WMC_WANA100F)
			cmd->advertising |= ADVERTISED_100baseT_Full;
		if (ctrl & WMC_WANA100H)
			cmd->advertising |= ADVERTISED_100baseT_Half;
		if (ctrl & WMC_WANA10F)
			cmd->advertising |= ADVERTISED_10baseT_Full;
		if (ctrl & WMC_WANA10H)
			cmd->advertising |= ADVERTISED_10baseT_Half;
		if (ctrl & WMC_WANAP)
			cmd->advertising |= ADVERTISED_Pause;
		cmd->autoneg = AUTONEG_ENABLE;

		ethtool_cmd_speed_set(cmd,
				      (ctrl & WMC_WSS) ? SPEED_100 : SPEED_10);
		cmd->duplex = (ctrl & WMC_WDS) ?
			DUPLEX_FULL : DUPLEX_HALF;
	} else {
		/* auto-negotiation is disabled */
		cmd->autoneg = AUTONEG_DISABLE;

		ethtool_cmd_speed_set(cmd, ((ctrl & WMC_WANF100) ?
					    SPEED_100 : SPEED_10));
		cmd->duplex = (ctrl & WMC_WANFF) ?
			DUPLEX_FULL : DUPLEX_HALF;
	}

	return 0;
}

/**
 *	ks8695_wan_set_settings - Set device-specific settings.
 *	@ndev: The network device to configure
 *	@cmd: The settings to configure
 */
static int
ks8695_wan_set_settings(struct net_device *ndev, struct ethtool_cmd *cmd)
{
	struct ks8695_priv *ksp = netdev_priv(ndev);
	u32 ctrl;

	if ((cmd->speed != SPEED_10) && (cmd->speed != SPEED_100))
		return -EINVAL;
	if ((cmd->duplex != DUPLEX_HALF) && (cmd->duplex != DUPLEX_FULL))
		return -EINVAL;
	if (cmd->port != PORT_MII)
		return -EINVAL;
	if (cmd->transceiver != XCVR_INTERNAL)
		return -EINVAL;
	if ((cmd->autoneg != AUTONEG_DISABLE) &&
	    (cmd->autoneg != AUTONEG_ENABLE))
		return -EINVAL;

	if (cmd->autoneg == AUTONEG_ENABLE) {
		if ((cmd->advertising & (ADVERTISED_10baseT_Half |
				ADVERTISED_10baseT_Full |
				ADVERTISED_100baseT_Half |
				ADVERTISED_100baseT_Full)) == 0)
			return -EINVAL;

		ctrl = readl(ksp->phyiface_regs + KS8695_WMC);

		ctrl &= ~(WMC_WAND | WMC_WANA100F | WMC_WANA100H |
			  WMC_WANA10F | WMC_WANA10H);
		if (cmd->advertising & ADVERTISED_100baseT_Full)
			ctrl |= WMC_WANA100F;
		if (cmd->advertising & ADVERTISED_100baseT_Half)
			ctrl |= WMC_WANA100H;
		if (cmd->advertising & ADVERTISED_10baseT_Full)
			ctrl |= WMC_WANA10F;
		if (cmd->advertising & ADVERTISED_10baseT_Half)
			ctrl |= WMC_WANA10H;

		/* force a re-negotiation */
		ctrl |= WMC_WANR;
		writel(ctrl, ksp->phyiface_regs + KS8695_WMC);
	} else {
		ctrl = readl(ksp->phyiface_regs + KS8695_WMC);

		/* disable auto-negotiation */
		ctrl |= WMC_WAND;
		ctrl &= ~(WMC_WANF100 | WMC_WANFF);

		if (cmd->speed == SPEED_100)
			ctrl |= WMC_WANF100;
		if (cmd->duplex == DUPLEX_FULL)
			ctrl |= WMC_WANFF;

		writel(ctrl, ksp->phyiface_regs + KS8695_WMC);
	}

	return 0;
}

/**
 *	ks8695_wan_nwayreset - Restart the autonegotiation on the port.
 *	@ndev: The network device to restart autoneotiation on
 */
static int
ks8695_wan_nwayreset(struct net_device *ndev)
{
	struct ks8695_priv *ksp = netdev_priv(ndev);
	u32 ctrl;

	ctrl = readl(ksp->phyiface_regs + KS8695_WMC);

	if ((ctrl & WMC_WAND) == 0)
		writel(ctrl | WMC_WANR,
		       ksp->phyiface_regs + KS8695_WMC);
	else
		/* auto-negotiation not enabled */
		return -EINVAL;

	return 0;
}

/**
 *	ks8695_wan_get_pause - Retrieve network pause/flow-control advertising
 *	@ndev: The device to retrieve settings from
 *	@param: The structure to fill out with the information
 */
static void
ks8695_wan_get_pause(struct net_device *ndev, struct ethtool_pauseparam *param)
{
	struct ks8695_priv *ksp = netdev_priv(ndev);
	u32 ctrl;

	ctrl = readl(ksp->phyiface_regs + KS8695_WMC);

	/* advertise Pause */
	param->autoneg = (ctrl & WMC_WANAP);

	/* current Rx Flow-control */
	ctrl = ks8695_readreg(ksp, KS8695_DRXC);
	param->rx_pause = (ctrl & DRXC_RFCE);

	/* current Tx Flow-control */
	ctrl = ks8695_readreg(ksp, KS8695_DTXC);
	param->tx_pause = (ctrl & DTXC_TFCE);
}

/**
 *	ks8695_get_drvinfo - Retrieve driver information
 *	@ndev: The network device to retrieve info about
 *	@info: The info structure to fill out.
 */
static void
ks8695_get_drvinfo(struct net_device *ndev, struct ethtool_drvinfo *info)
{
	strlcpy(info->driver, MODULENAME, sizeof(info->driver));
	strlcpy(info->version, MODULEVERSION, sizeof(info->version));
	strlcpy(info->bus_info, dev_name(ndev->dev.parent),
		sizeof(info->bus_info));
}

static const struct ethtool_ops ks8695_ethtool_ops = {
	.get_msglevel	= ks8695_get_msglevel,
	.set_msglevel	= ks8695_set_msglevel,
	.get_drvinfo	= ks8695_get_drvinfo,
};

static const struct ethtool_ops ks8695_wan_ethtool_ops = {
	.get_msglevel	= ks8695_get_msglevel,
	.set_msglevel	= ks8695_set_msglevel,
	.get_settings	= ks8695_wan_get_settings,
	.set_settings	= ks8695_wan_set_settings,
	.nway_reset	= ks8695_wan_nwayreset,
	.get_link	= ethtool_op_get_link,
	.get_pauseparam = ks8695_wan_get_pause,
	.get_drvinfo	= ks8695_get_drvinfo,
};

/* Network device interface functions */

/**
 *	ks8695_set_mac - Update MAC in net dev and HW
 *	@ndev: The network device to update
 *	@addr: The new MAC address to set
 */
static int
ks8695_set_mac(struct net_device *ndev, void *addr)
{
	struct ks8695_priv *ksp = netdev_priv(ndev);
	struct sockaddr *address = addr;

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

	memcpy(ndev->dev_addr, address->sa_data, ndev->addr_len);

	ks8695_update_mac(ksp);

	dev_dbg(ksp->dev, "%s: Updated MAC address to %pM\n",
		ndev->name, ndev->dev_addr);

	return 0;
}

/**
 *	ks8695_set_multicast - Set up the multicast behaviour of the interface
 *	@ndev: The net_device to configure
 *
 *	This routine, called by the net layer, configures promiscuity
 *	and multicast reception behaviour for the interface.
 */
static void
ks8695_set_multicast(struct net_device *ndev)
{
	struct ks8695_priv *ksp = netdev_priv(ndev);
	u32 ctrl;

	ctrl = ks8695_readreg(ksp, KS8695_DRXC);

	if (ndev->flags & IFF_PROMISC) {
		/* enable promiscuous mode */
		ctrl |= DRXC_RA;
	} else if (ndev->flags & ~IFF_PROMISC) {
		/* disable promiscuous mode */
		ctrl &= ~DRXC_RA;
	}

	if (ndev->flags & IFF_ALLMULTI) {
		/* enable all multicast mode */
		ctrl |= DRXC_RM;
	} else if (netdev_mc_count(ndev) > KS8695_NR_ADDRESSES) {
		/* more specific multicast addresses than can be
		 * handled in hardware
		 */
		ctrl |= DRXC_RM;
	} else {
		/* enable specific multicasts */
		ctrl &= ~DRXC_RM;
		ks8695_init_partial_multicast(ksp, ndev);
	}

	ks8695_writereg(ksp, KS8695_DRXC, ctrl);
}

/**
 *	ks8695_timeout - Handle a network tx/rx timeout.
 *	@ndev: The net_device which timed out.
 *
 *	A network transaction timed out, reset the device.
 */
static void
ks8695_timeout(struct net_device *ndev)
{
	struct ks8695_priv *ksp = netdev_priv(ndev);

	netif_stop_queue(ndev);
	ks8695_shutdown(ksp);

	ks8695_reset(ksp);

	ks8695_update_mac(ksp);

	/* We ignore the return from this since it managed to init
	 * before it probably will be okay to init again.
	 */
	ks8695_init_net(ksp);

	/* Reconfigure promiscuity etc */
	ks8695_set_multicast(ndev);

	/* And start the TX queue once more */
	netif_start_queue(ndev);
}

/**
 *	ks8695_start_xmit - Start a packet transmission
 *	@skb: The packet to transmit
 *	@ndev: The network device to send the packet on
 *
 *	This routine, called by the net layer, takes ownership of the
 *	sk_buff and adds it to the TX ring. It then kicks the TX DMA
 *	engine to ensure transmission begins.
 */
static int
ks8695_start_xmit(struct sk_buff *skb, struct net_device *ndev)
{
	struct ks8695_priv *ksp = netdev_priv(ndev);
	int buff_n;
	dma_addr_t dmap;

	spin_lock_irq(&ksp->txq_lock);

	if (ksp->tx_ring_used == MAX_TX_DESC) {
		/* Somehow we got entered when we have no room */
		spin_unlock_irq(&ksp->txq_lock);
		return NETDEV_TX_BUSY;
	}

	buff_n = ksp->tx_ring_next_slot;

	BUG_ON(ksp->tx_buffers[buff_n].skb);

	dmap = dma_map_single(ksp->dev, skb->data, skb->len, DMA_TO_DEVICE);
	if (unlikely(dma_mapping_error(ksp->dev, dmap))) {
		/* Failed to DMA map this SKB, give it back for now */
		spin_unlock_irq(&ksp->txq_lock);
		dev_dbg(ksp->dev, "%s: Could not map DMA memory for "\
			"transmission, trying later\n", ndev->name);
		return NETDEV_TX_BUSY;
	}

	ksp->tx_buffers[buff_n].dma_ptr = dmap;
	/* Mapped okay, store the buffer pointer and length for later */
	ksp->tx_buffers[buff_n].skb = skb;
	ksp->tx_buffers[buff_n].length = skb->len;

	/* Fill out the TX descriptor */
	ksp->tx_ring[buff_n].data_ptr =
		cpu_to_le32(ksp->tx_buffers[buff_n].dma_ptr);
	ksp->tx_ring[buff_n].status =
		cpu_to_le32(TDES_IC | TDES_FS | TDES_LS |
			    (skb->len & TDES_TBS));

	wmb();

	/* Hand it over to the hardware */
	ksp->tx_ring[buff_n].owner = cpu_to_le32(TDES_OWN);

	if (++ksp->tx_ring_used == MAX_TX_DESC)
		netif_stop_queue(ndev);

	/* Kick the TX DMA in case it decided to go IDLE */
	ks8695_writereg(ksp, KS8695_DTSC, 0);

	/* And update the next ring slot */
	ksp->tx_ring_next_slot = (buff_n + 1) & MAX_TX_DESC_MASK;

	spin_unlock_irq(&ksp->txq_lock);
	return NETDEV_TX_OK;
}

/**
 *	ks8695_stop - Stop (shutdown) a KS8695 ethernet interface
 *	@ndev: The net_device to stop
 *
 *	This disables the TX queue and cleans up a KS8695 ethernet
 *	device.
 */
static int
ks8695_stop(struct net_device *ndev)
{
	struct ks8695_priv *ksp = netdev_priv(ndev);

	netif_stop_queue(ndev);
	napi_disable(&ksp->napi);

	ks8695_shutdown(ksp);

	return 0;
}

/**
 *	ks8695_open - Open (bring up) a KS8695 ethernet interface
 *	@ndev: The net_device to open
 *
 *	This resets, configures the MAC, initialises the RX ring and
 *	DMA engines and starts the TX queue for a KS8695 ethernet
 *	device.
 */
static int
ks8695_open(struct net_device *ndev)
{
	struct ks8695_priv *ksp = netdev_priv(ndev);
	int ret;

	ks8695_reset(ksp);

	ks8695_update_mac(ksp);

	ret = ks8695_init_net(ksp);
	if (ret) {
		ks8695_shutdown(ksp);
		return ret;
	}

	napi_enable(&ksp->napi);
	netif_start_queue(ndev);

	return 0;
}

/* Platform device driver */

/**
 *	ks8695_init_switch - Init LAN switch to known good defaults.
 *	@ksp: The device to initialise
 *
 *	This initialises the LAN switch in the KS8695 to a known-good
 *	set of defaults.
 */
static void
ks8695_init_switch(struct ks8695_priv *ksp)
{
	u32 ctrl;

	/* Default value for SEC0 according to datasheet */
	ctrl = 0x40819e00;

	/* LED0 = Speed	 LED1 = Link/Activity */
	ctrl &= ~(SEC0_LLED1S | SEC0_LLED0S);
	ctrl |= (LLED0S_LINK | LLED1S_LINK_ACTIVITY);

	/* Enable Switch */
	ctrl |= SEC0_ENABLE;

	writel(ctrl, ksp->phyiface_regs + KS8695_SEC0);

	/* Defaults for SEC1 */
	writel(0x9400100, ksp->phyiface_regs + KS8695_SEC1);
}

/**
 *	ks8695_init_wan_phy - Initialise the WAN PHY to sensible defaults
 *	@ksp: The device to initialise
 *
 *	This initialises a KS8695's WAN phy to sensible values for
 *	autonegotiation etc.
 */
static void
ks8695_init_wan_phy(struct ks8695_priv *ksp)
{
	u32 ctrl;

	/* Support auto-negotiation */
	ctrl = (WMC_WANAP | WMC_WANA100F | WMC_WANA100H |
		WMC_WANA10F | WMC_WANA10H);

	/* LED0 = Activity , LED1 = Link */
	ctrl |= (WLED0S_ACTIVITY | WLED1S_LINK);

	/* Restart Auto-negotiation */
	ctrl |= WMC_WANR;

	writel(ctrl, ksp->phyiface_regs + KS8695_WMC);

	writel(0, ksp->phyiface_regs + KS8695_WPPM);
	writel(0, ksp->phyiface_regs + KS8695_PPS);
}

static const struct net_device_ops ks8695_netdev_ops = {
	.ndo_open		= ks8695_open,
	.ndo_stop		= ks8695_stop,
	.ndo_start_xmit		= ks8695_start_xmit,
	.ndo_tx_timeout		= ks8695_timeout,
	.ndo_set_mac_address	= ks8695_set_mac,
	.ndo_validate_addr	= eth_validate_addr,
	.ndo_set_rx_mode	= ks8695_set_multicast,
};

/**
 *	ks8695_probe - Probe and initialise a KS8695 ethernet interface
 *	@pdev: The platform device to probe
 *
 *	Initialise a KS8695 ethernet device from platform data.
 *
 *	This driver requires at least one IORESOURCE_MEM for the
 *	registers and two IORESOURCE_IRQ for the RX and TX IRQs
 *	respectively. It can optionally take an additional
 *	IORESOURCE_MEM for the switch or phy in the case of the lan or
 *	wan ports, and an IORESOURCE_IRQ for the link IRQ for the wan
 *	port.
 */
static int
ks8695_probe(struct platform_device *pdev)
{
	struct ks8695_priv *ksp;
	struct net_device *ndev;
	struct resource *regs_res, *phyiface_res;
	struct resource *rxirq_res, *txirq_res, *linkirq_res;
	int ret = 0;
	int buff_n;
	u32 machigh, maclow;

	/* Initialise a net_device */
	ndev = alloc_etherdev(sizeof(struct ks8695_priv));
	if (!ndev)
		return -ENOMEM;

	SET_NETDEV_DEV(ndev, &pdev->dev);

	dev_dbg(&pdev->dev, "ks8695_probe() called\n");

	/* Configure our private structure a little */
	ksp = netdev_priv(ndev);

	ksp->dev = &pdev->dev;
	ksp->ndev = ndev;
	ksp->msg_enable = NETIF_MSG_LINK;

	/* Retrieve resources */
	regs_res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
	phyiface_res = platform_get_resource(pdev, IORESOURCE_MEM, 1);

	rxirq_res = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
	txirq_res = platform_get_resource(pdev, IORESOURCE_IRQ, 1);
	linkirq_res = platform_get_resource(pdev, IORESOURCE_IRQ, 2);

	if (!(regs_res && rxirq_res && txirq_res)) {
		dev_err(ksp->dev, "insufficient resources\n");
		ret = -ENOENT;
		goto failure;
	}

	ksp->regs_req = request_mem_region(regs_res->start,
					   resource_size(regs_res),
					   pdev->name);

	if (!ksp->regs_req) {
		dev_err(ksp->dev, "cannot claim register space\n");
		ret = -EIO;
		goto failure;
	}

	ksp->io_regs = ioremap(regs_res->start, resource_size(regs_res));

	if (!ksp->io_regs) {
		dev_err(ksp->dev, "failed to ioremap registers\n");
		ret = -EINVAL;
		goto failure;
	}

	if (phyiface_res) {
		ksp->phyiface_req =
			request_mem_region(phyiface_res->start,
					   resource_size(phyiface_res),
					   phyiface_res->name);

		if (!ksp->phyiface_req) {
			dev_err(ksp->dev,
				"cannot claim switch register space\n");
			ret = -EIO;
			goto failure;
		}

		ksp->phyiface_regs = ioremap(phyiface_res->start,
					     resource_size(phyiface_res));

		if (!ksp->phyiface_regs) {
			dev_err(ksp->dev,
				"failed to ioremap switch registers\n");
			ret = -EINVAL;
			goto failure;
		}
	}

	ksp->rx_irq = rxirq_res->start;
	ksp->rx_irq_name = rxirq_res->name ? rxirq_res->name : "Ethernet RX";
	ksp->tx_irq = txirq_res->start;
	ksp->tx_irq_name = txirq_res->name ? txirq_res->name : "Ethernet TX";
	ksp->link_irq = (linkirq_res ? linkirq_res->start : -1);
	ksp->link_irq_name = (linkirq_res && linkirq_res->name) ?
		linkirq_res->name : "Ethernet Link";

	/* driver system setup */
	ndev->netdev_ops = &ks8695_netdev_ops;
	ndev->watchdog_timeo	 = msecs_to_jiffies(watchdog);

	netif_napi_add(ndev, &ksp->napi, ks8695_poll, NAPI_WEIGHT);

	/* Retrieve the default MAC addr from the chip. */
	/* The bootloader should have left it in there for us. */

	machigh = ks8695_readreg(ksp, KS8695_MAH);
	maclow = ks8695_readreg(ksp, KS8695_MAL);

	ndev->dev_addr[0] = (machigh >> 8) & 0xFF;
	ndev->dev_addr[1] = machigh & 0xFF;
	ndev->dev_addr[2] = (maclow >> 24) & 0xFF;
	ndev->dev_addr[3] = (maclow >> 16) & 0xFF;
	ndev->dev_addr[4] = (maclow >> 8) & 0xFF;
	ndev->dev_addr[5] = maclow & 0xFF;

	if (!is_valid_ether_addr(ndev->dev_addr))
		dev_warn(ksp->dev, "%s: Invalid ethernet MAC address. Please "
			 "set using ifconfig\n", ndev->name);

	/* In order to be efficient memory-wise, we allocate both
	 * rings in one go.
	 */
	ksp->ring_base = dma_alloc_coherent(&pdev->dev, RING_DMA_SIZE,
					    &ksp->ring_base_dma, GFP_KERNEL);
	if (!ksp->ring_base) {
		ret = -ENOMEM;
		goto failure;
	}

	/* Specify the TX DMA ring buffer */
	ksp->tx_ring = ksp->ring_base;
	ksp->tx_ring_dma = ksp->ring_base_dma;

	/* And initialise the queue's lock */
	spin_lock_init(&ksp->txq_lock);
	spin_lock_init(&ksp->rx_lock);

	/* Specify the RX DMA ring buffer */
	ksp->rx_ring = ksp->ring_base + TX_RING_DMA_SIZE;
	ksp->rx_ring_dma = ksp->ring_base_dma + TX_RING_DMA_SIZE;

	/* Zero the descriptor rings */
	memset(ksp->tx_ring, 0, TX_RING_DMA_SIZE);
	memset(ksp->rx_ring, 0, RX_RING_DMA_SIZE);

	/* Build the rings */
	for (buff_n = 0; buff_n < MAX_TX_DESC; ++buff_n) {
		ksp->tx_ring[buff_n].next_desc =
			cpu_to_le32(ksp->tx_ring_dma +
				    (sizeof(struct tx_ring_desc) *
				     ((buff_n + 1) & MAX_TX_DESC_MASK)));
	}

	for (buff_n = 0; buff_n < MAX_RX_DESC; ++buff_n) {
		ksp->rx_ring[buff_n].next_desc =
			cpu_to_le32(ksp->rx_ring_dma +
				    (sizeof(struct rx_ring_desc) *
				     ((buff_n + 1) & MAX_RX_DESC_MASK)));
	}

	/* Initialise the port (physically) */
	if (ksp->phyiface_regs && ksp->link_irq == -1) {
		ks8695_init_switch(ksp);
		ksp->dtype = KS8695_DTYPE_LAN;
		SET_ETHTOOL_OPS(ndev, &ks8695_ethtool_ops);
	} else if (ksp->phyiface_regs && ksp->link_irq != -1) {
		ks8695_init_wan_phy(ksp);
		ksp->dtype = KS8695_DTYPE_WAN;
		SET_ETHTOOL_OPS(ndev, &ks8695_wan_ethtool_ops);
	} else {
		/* No initialisation since HPNA does not have a PHY */
		ksp->dtype = KS8695_DTYPE_HPNA;
		SET_ETHTOOL_OPS(ndev, &ks8695_ethtool_ops);
	}

	/* And bring up the net_device with the net core */
	platform_set_drvdata(pdev, ndev);
	ret = register_netdev(ndev);

	if (ret == 0) {
		dev_info(ksp->dev, "ks8695 ethernet (%s) MAC: %pM\n",
			 ks8695_port_type(ksp), ndev->dev_addr);
	} else {
		/* Report the failure to register the net_device */
		dev_err(ksp->dev, "ks8695net: failed to register netdev.\n");
		goto failure;
	}

	/* All is well */
	return 0;

	/* Error exit path */
failure:
	ks8695_release_device(ksp);
	free_netdev(ndev);

	return ret;
}

/**
 *	ks8695_drv_suspend - Suspend a KS8695 ethernet platform device.
 *	@pdev: The device to suspend
 *	@state: The suspend state
 *
 *	This routine detaches and shuts down a KS8695 ethernet device.
 */
static int
ks8695_drv_suspend(struct platform_device *pdev, pm_message_t state)
{
	struct net_device *ndev = platform_get_drvdata(pdev);
	struct ks8695_priv *ksp = netdev_priv(ndev);

	ksp->in_suspend = 1;

	if (netif_running(ndev)) {
		netif_device_detach(ndev);
		ks8695_shutdown(ksp);
	}

	return 0;
}

/**
 *	ks8695_drv_resume - Resume a KS8695 ethernet platform device.
 *	@pdev: The device to resume
 *
 *	This routine re-initialises and re-attaches a KS8695 ethernet
 *	device.
 */
static int
ks8695_drv_resume(struct platform_device *pdev)
{
	struct net_device *ndev = platform_get_drvdata(pdev);
	struct ks8695_priv *ksp = netdev_priv(ndev);

	if (netif_running(ndev)) {
		ks8695_reset(ksp);
		ks8695_init_net(ksp);
		ks8695_set_multicast(ndev);
		netif_device_attach(ndev);
	}

	ksp->in_suspend = 0;

	return 0;
}

/**
 *	ks8695_drv_remove - Remove a KS8695 net device on driver unload.
 *	@pdev: The platform device to remove
 *
 *	This unregisters and releases a KS8695 ethernet device.
 */
static int
ks8695_drv_remove(struct platform_device *pdev)
{
	struct net_device *ndev = platform_get_drvdata(pdev);
	struct ks8695_priv *ksp = netdev_priv(ndev);

	platform_set_drvdata(pdev, NULL);
	netif_napi_del(&ksp->napi);

	unregister_netdev(ndev);
	ks8695_release_device(ksp);
	free_netdev(ndev);

	dev_dbg(&pdev->dev, "released and freed device\n");
	return 0;
}

static struct platform_driver ks8695_driver = {
	.driver = {
		.name	= MODULENAME,
		.owner	= THIS_MODULE,
	},
	.probe		= ks8695_probe,
	.remove		= ks8695_drv_remove,
	.suspend	= ks8695_drv_suspend,
	.resume		= ks8695_drv_resume,
};

module_platform_driver(ks8695_driver);

MODULE_AUTHOR("Simtec Electronics");
MODULE_DESCRIPTION("Micrel KS8695 (Centaur) Ethernet driver");
MODULE_LICENSE("GPL");
MODULE_ALIAS("platform:" MODULENAME);

module_param(watchdog, int, 0400);
MODULE_PARM_DESC(watchdog, "transmit timeout in milliseconds");