summaryrefslogtreecommitdiffstats
path: root/drivers/net/ethernet/sfc/net_driver.h
blob: bdded38cbf125d42a0d45846e76b016efbc40211 (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
/****************************************************************************
 * Driver for Solarflare Solarstorm network controllers and boards
 * Copyright 2005-2006 Fen Systems Ltd.
 * Copyright 2005-2011 Solarflare Communications Inc.
 *
 * This program is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 as published
 * by the Free Software Foundation, incorporated herein by reference.
 */

/* Common definitions for all Efx net driver code */

#ifndef EFX_NET_DRIVER_H
#define EFX_NET_DRIVER_H

#include <linux/netdevice.h>
#include <linux/etherdevice.h>
#include <linux/ethtool.h>
#include <linux/if_vlan.h>
#include <linux/timer.h>
#include <linux/mdio.h>
#include <linux/list.h>
#include <linux/pci.h>
#include <linux/device.h>
#include <linux/highmem.h>
#include <linux/workqueue.h>
#include <linux/mutex.h>
#include <linux/vmalloc.h>
#include <linux/i2c.h>

#include "enum.h"
#include "bitfield.h"

/**************************************************************************
 *
 * Build definitions
 *
 **************************************************************************/

#define EFX_DRIVER_VERSION	"3.2"

#ifdef DEBUG
#define EFX_BUG_ON_PARANOID(x) BUG_ON(x)
#define EFX_WARN_ON_PARANOID(x) WARN_ON(x)
#else
#define EFX_BUG_ON_PARANOID(x) do {} while (0)
#define EFX_WARN_ON_PARANOID(x) do {} while (0)
#endif

/**************************************************************************
 *
 * Efx data structures
 *
 **************************************************************************/

#define EFX_MAX_CHANNELS 32U
#define EFX_MAX_RX_QUEUES EFX_MAX_CHANNELS
#define EFX_EXTRA_CHANNEL_IOV	0
#define EFX_EXTRA_CHANNEL_PTP	1
#define EFX_MAX_EXTRA_CHANNELS	2U

/* Checksum generation is a per-queue option in hardware, so each
 * queue visible to the networking core is backed by two hardware TX
 * queues. */
#define EFX_MAX_TX_TC		2
#define EFX_MAX_CORE_TX_QUEUES	(EFX_MAX_TX_TC * EFX_MAX_CHANNELS)
#define EFX_TXQ_TYPE_OFFLOAD	1	/* flag */
#define EFX_TXQ_TYPE_HIGHPRI	2	/* flag */
#define EFX_TXQ_TYPES		4
#define EFX_MAX_TX_QUEUES	(EFX_TXQ_TYPES * EFX_MAX_CHANNELS)

/* Maximum possible MTU the driver supports */
#define EFX_MAX_MTU (9 * 1024)

/* Size of an RX scatter buffer.  Small enough to pack 2 into a 4K page,
 * and should be a multiple of the cache line size.
 */
#define EFX_RX_USR_BUF_SIZE	(2048 - 256)

/* If possible, we should ensure cache line alignment at start and end
 * of every buffer.  Otherwise, we just need to ensure 4-byte
 * alignment of the network header.
 */
#if NET_IP_ALIGN == 0
#define EFX_RX_BUF_ALIGNMENT	L1_CACHE_BYTES
#else
#define EFX_RX_BUF_ALIGNMENT	4
#endif

/* Forward declare Precision Time Protocol (PTP) support structure. */
struct efx_ptp_data;

struct efx_self_tests;

/**
 * struct efx_special_buffer - An Efx special buffer
 * @addr: CPU base address of the buffer
 * @dma_addr: DMA base address of the buffer
 * @len: Buffer length, in bytes
 * @index: Buffer index within controller;s buffer table
 * @entries: Number of buffer table entries
 *
 * Special buffers are used for the event queues and the TX and RX
 * descriptor queues for each channel.  They are *not* used for the
 * actual transmit and receive buffers.
 */
struct efx_special_buffer {
	void *addr;
	dma_addr_t dma_addr;
	unsigned int len;
	unsigned int index;
	unsigned int entries;
};

/**
 * struct efx_tx_buffer - buffer state for a TX descriptor
 * @skb: When @flags & %EFX_TX_BUF_SKB, the associated socket buffer to be
 *	freed when descriptor completes
 * @heap_buf: When @flags & %EFX_TX_BUF_HEAP, the associated heap buffer to be
 *	freed when descriptor completes.
 * @dma_addr: DMA address of the fragment.
 * @flags: Flags for allocation and DMA mapping type
 * @len: Length of this fragment.
 *	This field is zero when the queue slot is empty.
 * @unmap_len: Length of this fragment to unmap
 */
struct efx_tx_buffer {
	union {
		const struct sk_buff *skb;
		void *heap_buf;
	};
	dma_addr_t dma_addr;
	unsigned short flags;
	unsigned short len;
	unsigned short unmap_len;
};
#define EFX_TX_BUF_CONT		1	/* not last descriptor of packet */
#define EFX_TX_BUF_SKB		2	/* buffer is last part of skb */
#define EFX_TX_BUF_HEAP		4	/* buffer was allocated with kmalloc() */
#define EFX_TX_BUF_MAP_SINGLE	8	/* buffer was mapped with dma_map_single() */

/**
 * struct efx_tx_queue - An Efx TX queue
 *
 * This is a ring buffer of TX fragments.
 * Since the TX completion path always executes on the same
 * CPU and the xmit path can operate on different CPUs,
 * performance is increased by ensuring that the completion
 * path and the xmit path operate on different cache lines.
 * This is particularly important if the xmit path is always
 * executing on one CPU which is different from the completion
 * path.  There is also a cache line for members which are
 * read but not written on the fast path.
 *
 * @efx: The associated Efx NIC
 * @queue: DMA queue number
 * @channel: The associated channel
 * @core_txq: The networking core TX queue structure
 * @buffer: The software buffer ring
 * @tsoh_page: Array of pages of TSO header buffers
 * @txd: The hardware descriptor ring
 * @ptr_mask: The size of the ring minus 1.
 * @initialised: Has hardware queue been initialised?
 * @read_count: Current read pointer.
 *	This is the number of buffers that have been removed from both rings.
 * @old_write_count: The value of @write_count when last checked.
 *	This is here for performance reasons.  The xmit path will
 *	only get the up-to-date value of @write_count if this
 *	variable indicates that the queue is empty.  This is to
 *	avoid cache-line ping-pong between the xmit path and the
 *	completion path.
 * @insert_count: Current insert pointer
 *	This is the number of buffers that have been added to the
 *	software ring.
 * @write_count: Current write pointer
 *	This is the number of buffers that have been added to the
 *	hardware ring.
 * @old_read_count: The value of read_count when last checked.
 *	This is here for performance reasons.  The xmit path will
 *	only get the up-to-date value of read_count if this
 *	variable indicates that the queue is full.  This is to
 *	avoid cache-line ping-pong between the xmit path and the
 *	completion path.
 * @tso_bursts: Number of times TSO xmit invoked by kernel
 * @tso_long_headers: Number of packets with headers too long for standard
 *	blocks
 * @tso_packets: Number of packets via the TSO xmit path
 * @pushes: Number of times the TX push feature has been used
 * @empty_read_count: If the completion path has seen the queue as empty
 *	and the transmission path has not yet checked this, the value of
 *	@read_count bitwise-added to %EFX_EMPTY_COUNT_VALID; otherwise 0.
 */
struct efx_tx_queue {
	/* Members which don't change on the fast path */
	struct efx_nic *efx ____cacheline_aligned_in_smp;
	unsigned queue;
	struct efx_channel *channel;
	struct netdev_queue *core_txq;
	struct efx_tx_buffer *buffer;
	struct efx_buffer *tsoh_page;
	struct efx_special_buffer txd;
	unsigned int ptr_mask;
	bool initialised;

	/* Members used mainly on the completion path */
	unsigned int read_count ____cacheline_aligned_in_smp;
	unsigned int old_write_count;

	/* Members used only on the xmit path */
	unsigned int insert_count ____cacheline_aligned_in_smp;
	unsigned int write_count;
	unsigned int old_read_count;
	unsigned int tso_bursts;
	unsigned int tso_long_headers;
	unsigned int tso_packets;
	unsigned int pushes;

	/* Members shared between paths and sometimes updated */
	unsigned int empty_read_count ____cacheline_aligned_in_smp;
#define EFX_EMPTY_COUNT_VALID 0x80000000
	atomic_t flush_outstanding;
};

/**
 * struct efx_rx_buffer - An Efx RX data buffer
 * @dma_addr: DMA base address of the buffer
 * @page: The associated page buffer.
 *	Will be %NULL if the buffer slot is currently free.
 * @page_offset: If pending: offset in @page of DMA base address.
 *	If completed: offset in @page of Ethernet header.
 * @len: If pending: length for DMA descriptor.
 *	If completed: received length, excluding hash prefix.
 * @flags: Flags for buffer and packet state.  These are only set on the
 *	first buffer of a scattered packet.
 */
struct efx_rx_buffer {
	dma_addr_t dma_addr;
	struct page *page;
	u16 page_offset;
	u16 len;
	u16 flags;
};
#define EFX_RX_BUF_LAST_IN_PAGE	0x0001
#define EFX_RX_PKT_CSUMMED	0x0002
#define EFX_RX_PKT_DISCARD	0x0004
#define EFX_RX_PKT_TCP		0x0040

/**
 * struct efx_rx_page_state - Page-based rx buffer state
 *
 * Inserted at the start of every page allocated for receive buffers.
 * Used to facilitate sharing dma mappings between recycled rx buffers
 * and those passed up to the kernel.
 *
 * @refcnt: Number of struct efx_rx_buffer's referencing this page.
 *	When refcnt falls to zero, the page is unmapped for dma
 * @dma_addr: The dma address of this page.
 */
struct efx_rx_page_state {
	unsigned refcnt;
	dma_addr_t dma_addr;

	unsigned int __pad[0] ____cacheline_aligned;
};

/**
 * struct efx_rx_queue - An Efx RX queue
 * @efx: The associated Efx NIC
 * @core_index:  Index of network core RX queue.  Will be >= 0 iff this
 *	is associated with a real RX queue.
 * @buffer: The software buffer ring
 * @rxd: The hardware descriptor ring
 * @ptr_mask: The size of the ring minus 1.
 * @enabled: Receive queue enabled indicator.
 * @flush_pending: Set when a RX flush is pending. Has the same lifetime as
 *	@rxq_flush_pending.
 * @added_count: Number of buffers added to the receive queue.
 * @notified_count: Number of buffers given to NIC (<= @added_count).
 * @removed_count: Number of buffers removed from the receive queue.
 * @scatter_n: Number of buffers used by current packet
 * @page_ring: The ring to store DMA mapped pages for reuse.
 * @page_add: Counter to calculate the write pointer for the recycle ring.
 * @page_remove: Counter to calculate the read pointer for the recycle ring.
 * @page_recycle_count: The number of pages that have been recycled.
 * @page_recycle_failed: The number of pages that couldn't be recycled because
 *      the kernel still held a reference to them.
 * @page_recycle_full: The number of pages that were released because the
 *      recycle ring was full.
 * @page_ptr_mask: The number of pages in the RX recycle ring minus 1.
 * @max_fill: RX descriptor maximum fill level (<= ring size)
 * @fast_fill_trigger: RX descriptor fill level that will trigger a fast fill
 *	(<= @max_fill)
 * @min_fill: RX descriptor minimum non-zero fill level.
 *	This records the minimum fill level observed when a ring
 *	refill was triggered.
 * @recycle_count: RX buffer recycle counter.
 * @slow_fill: Timer used to defer efx_nic_generate_fill_event().
 */
struct efx_rx_queue {
	struct efx_nic *efx;
	int core_index;
	struct efx_rx_buffer *buffer;
	struct efx_special_buffer rxd;
	unsigned int ptr_mask;
	bool enabled;
	bool flush_pending;

	unsigned int added_count;
	unsigned int notified_count;
	unsigned int removed_count;
	unsigned int scatter_n;
	struct page **page_ring;
	unsigned int page_add;
	unsigned int page_remove;
	unsigned int page_recycle_count;
	unsigned int page_recycle_failed;
	unsigned int page_recycle_full;
	unsigned int page_ptr_mask;
	unsigned int max_fill;
	unsigned int fast_fill_trigger;
	unsigned int min_fill;
	unsigned int min_overfill;
	unsigned int recycle_count;
	struct timer_list slow_fill;
	unsigned int slow_fill_count;
};

/**
 * struct efx_buffer - An Efx general-purpose buffer
 * @addr: host base address of the buffer
 * @dma_addr: DMA base address of the buffer
 * @len: Buffer length, in bytes
 *
 * The NIC uses these buffers for its interrupt status registers and
 * MAC stats dumps.
 */
struct efx_buffer {
	void *addr;
	dma_addr_t dma_addr;
	unsigned int len;
};


enum efx_rx_alloc_method {
	RX_ALLOC_METHOD_AUTO = 0,
	RX_ALLOC_METHOD_SKB = 1,
	RX_ALLOC_METHOD_PAGE = 2,
};

/**
 * struct efx_channel - An Efx channel
 *
 * A channel comprises an event queue, at least one TX queue, at least
 * one RX queue, and an associated tasklet for processing the event
 * queue.
 *
 * @efx: Associated Efx NIC
 * @channel: Channel instance number
 * @type: Channel type definition
 * @enabled: Channel enabled indicator
 * @irq: IRQ number (MSI and MSI-X only)
 * @irq_moderation: IRQ moderation value (in hardware ticks)
 * @napi_dev: Net device used with NAPI
 * @napi_str: NAPI control structure
 * @work_pending: Is work pending via NAPI?
 * @eventq: Event queue buffer
 * @eventq_mask: Event queue pointer mask
 * @eventq_read_ptr: Event queue read pointer
 * @event_test_cpu: Last CPU to handle interrupt or test event for this channel
 * @irq_count: Number of IRQs since last adaptive moderation decision
 * @irq_mod_score: IRQ moderation score
 * @n_rx_tobe_disc: Count of RX_TOBE_DISC errors
 * @n_rx_ip_hdr_chksum_err: Count of RX IP header checksum errors
 * @n_rx_tcp_udp_chksum_err: Count of RX TCP and UDP checksum errors
 * @n_rx_mcast_mismatch: Count of unmatched multicast frames
 * @n_rx_frm_trunc: Count of RX_FRM_TRUNC errors
 * @n_rx_overlength: Count of RX_OVERLENGTH errors
 * @n_skbuff_leaks: Count of skbuffs leaked due to RX overrun
 * @n_rx_nodesc_trunc: Number of RX packets truncated and then dropped due to
 *	lack of descriptors
 * @rx_pkt_n_frags: Number of fragments in next packet to be delivered by
 *	__efx_rx_packet(), or zero if there is none
 * @rx_pkt_index: Ring index of first buffer for next packet to be delivered
 *	by __efx_rx_packet(), if @rx_pkt_n_frags != 0
 * @rx_queue: RX queue for this channel
 * @tx_queue: TX queues for this channel
 */
struct efx_channel {
	struct efx_nic *efx;
	int channel;
	const struct efx_channel_type *type;
	bool enabled;
	int irq;
	unsigned int irq_moderation;
	struct net_device *napi_dev;
	struct napi_struct napi_str;
	bool work_pending;
	struct efx_special_buffer eventq;
	unsigned int eventq_mask;
	unsigned int eventq_read_ptr;
	int event_test_cpu;

	unsigned int irq_count;
	unsigned int irq_mod_score;
#ifdef CONFIG_RFS_ACCEL
	unsigned int rfs_filters_added;
#endif

	unsigned n_rx_tobe_disc;
	unsigned n_rx_ip_hdr_chksum_err;
	unsigned n_rx_tcp_udp_chksum_err;
	unsigned n_rx_mcast_mismatch;
	unsigned n_rx_frm_trunc;
	unsigned n_rx_overlength;
	unsigned n_skbuff_leaks;
	unsigned int n_rx_nodesc_trunc;

	unsigned int rx_pkt_n_frags;
	unsigned int rx_pkt_index;

	struct efx_rx_queue rx_queue;
	struct efx_tx_queue tx_queue[EFX_TXQ_TYPES];
};

/**
 * struct efx_channel_type - distinguishes traffic and extra channels
 * @handle_no_channel: Handle failure to allocate an extra channel
 * @pre_probe: Set up extra state prior to initialisation
 * @post_remove: Tear down extra state after finalisation, if allocated.
 *	May be called on channels that have not been probed.
 * @get_name: Generate the channel's name (used for its IRQ handler)
 * @copy: Copy the channel state prior to reallocation.  May be %NULL if
 *	reallocation is not supported.
 * @receive_skb: Handle an skb ready to be passed to netif_receive_skb()
 * @keep_eventq: Flag for whether event queue should be kept initialised
 *	while the device is stopped
 */
struct efx_channel_type {
	void (*handle_no_channel)(struct efx_nic *);
	int (*pre_probe)(struct efx_channel *);
	void (*post_remove)(struct efx_channel *);
	void (*get_name)(struct efx_channel *, char *buf, size_t len);
	struct efx_channel *(*copy)(const struct efx_channel *);
	bool (*receive_skb)(struct efx_channel *, struct sk_buff *);
	bool keep_eventq;
};

enum efx_led_mode {
	EFX_LED_OFF	= 0,
	EFX_LED_ON	= 1,
	EFX_LED_DEFAULT	= 2
};

#define STRING_TABLE_LOOKUP(val, member) \
	((val) < member ## _max) ? member ## _names[val] : "(invalid)"

extern const char *const efx_loopback_mode_names[];
extern const unsigned int efx_loopback_mode_max;
#define LOOPBACK_MODE(efx) \
	STRING_TABLE_LOOKUP((efx)->loopback_mode, efx_loopback_mode)

extern const char *const efx_reset_type_names[];
extern const unsigned int efx_reset_type_max;
#define RESET_TYPE(type) \
	STRING_TABLE_LOOKUP(type, efx_reset_type)

enum efx_int_mode {
	/* Be careful if altering to correct macro below */
	EFX_INT_MODE_MSIX = 0,
	EFX_INT_MODE_MSI = 1,
	EFX_INT_MODE_LEGACY = 2,
	EFX_INT_MODE_MAX	/* Insert any new items before this */
};
#define EFX_INT_MODE_USE_MSI(x) (((x)->interrupt_mode) <= EFX_INT_MODE_MSI)

enum nic_state {
	STATE_UNINIT = 0,	/* device being probed/removed or is frozen */
	STATE_READY = 1,	/* hardware ready and netdev registered */
	STATE_DISABLED = 2,	/* device disabled due to hardware errors */
	STATE_RECOVERY = 3,	/* device recovering from PCI error */
};

/*
 * Alignment of the skb->head which wraps a page-allocated RX buffer
 *
 * The skb allocated to wrap an rx_buffer can have this alignment. Since
 * the data is memcpy'd from the rx_buf, it does not need to be equal to
 * NET_IP_ALIGN.
 */
#define EFX_PAGE_SKB_ALIGN 2

/* Forward declaration */
struct efx_nic;

/* Pseudo bit-mask flow control field */
#define EFX_FC_RX	FLOW_CTRL_RX
#define EFX_FC_TX	FLOW_CTRL_TX
#define EFX_FC_AUTO	4

/**
 * struct efx_link_state - Current state of the link
 * @up: Link is up
 * @fd: Link is full-duplex
 * @fc: Actual flow control flags
 * @speed: Link speed (Mbps)
 */
struct efx_link_state {
	bool up;
	bool fd;
	u8 fc;
	unsigned int speed;
};

static inline bool efx_link_state_equal(const struct efx_link_state *left,
					const struct efx_link_state *right)
{
	return left->up == right->up && left->fd == right->fd &&
		left->fc == right->fc && left->speed == right->speed;
}

/**
 * struct efx_phy_operations - Efx PHY operations table
 * @probe: Probe PHY and initialise efx->mdio.mode_support, efx->mdio.mmds,
 *	efx->loopback_modes.
 * @init: Initialise PHY
 * @fini: Shut down PHY
 * @reconfigure: Reconfigure PHY (e.g. for new link parameters)
 * @poll: Update @link_state and report whether it changed.
 *	Serialised by the mac_lock.
 * @get_settings: Get ethtool settings. Serialised by the mac_lock.
 * @set_settings: Set ethtool settings. Serialised by the mac_lock.
 * @set_npage_adv: Set abilities advertised in (Extended) Next Page
 *	(only needed where AN bit is set in mmds)
 * @test_alive: Test that PHY is 'alive' (online)
 * @test_name: Get the name of a PHY-specific test/result
 * @run_tests: Run tests and record results as appropriate (offline).
 *	Flags are the ethtool tests flags.
 */
struct efx_phy_operations {
	int (*probe) (struct efx_nic *efx);
	int (*init) (struct efx_nic *efx);
	void (*fini) (struct efx_nic *efx);
	void (*remove) (struct efx_nic *efx);
	int (*reconfigure) (struct efx_nic *efx);
	bool (*poll) (struct efx_nic *efx);
	void (*get_settings) (struct efx_nic *efx,
			      struct ethtool_cmd *ecmd);
	int (*set_settings) (struct efx_nic *efx,
			     struct ethtool_cmd *ecmd);
	void (*set_npage_adv) (struct efx_nic *efx, u32);
	int (*test_alive) (struct efx_nic *efx);
	const char *(*test_name) (struct efx_nic *efx, unsigned int index);
	int (*run_tests) (struct efx_nic *efx, int *results, unsigned flags);
	int (*get_module_eeprom) (struct efx_nic *efx,
			       struct ethtool_eeprom *ee,
			       u8 *data);
	int (*get_module_info) (struct efx_nic *efx,
				struct ethtool_modinfo *modinfo);
};

/**
 * enum efx_phy_mode - PHY operating mode flags
 * @PHY_MODE_NORMAL: on and should pass traffic
 * @PHY_MODE_TX_DISABLED: on with TX disabled
 * @PHY_MODE_LOW_POWER: set to low power through MDIO
 * @PHY_MODE_OFF: switched off through external control
 * @PHY_MODE_SPECIAL: on but will not pass traffic
 */
enum efx_phy_mode {
	PHY_MODE_NORMAL		= 0,
	PHY_MODE_TX_DISABLED	= 1,
	PHY_MODE_LOW_POWER	= 2,
	PHY_MODE_OFF		= 4,
	PHY_MODE_SPECIAL	= 8,
};

static inline bool efx_phy_mode_disabled(enum efx_phy_mode mode)
{
	return !!(mode & ~PHY_MODE_TX_DISABLED);
}

/*
 * Efx extended statistics
 *
 * Not all statistics are provided by all supported MACs.  The purpose
 * is this structure is to contain the raw statistics provided by each
 * MAC.
 */
struct efx_mac_stats {
	u64 tx_bytes;
	u64 tx_good_bytes;
	u64 tx_bad_bytes;
	u64 tx_packets;
	u64 tx_bad;
	u64 tx_pause;
	u64 tx_control;
	u64 tx_unicast;
	u64 tx_multicast;
	u64 tx_broadcast;
	u64 tx_lt64;
	u64 tx_64;
	u64 tx_65_to_127;
	u64 tx_128_to_255;
	u64 tx_256_to_511;
	u64 tx_512_to_1023;
	u64 tx_1024_to_15xx;
	u64 tx_15xx_to_jumbo;
	u64 tx_gtjumbo;
	u64 tx_collision;
	u64 tx_single_collision;
	u64 tx_multiple_collision;
	u64 tx_excessive_collision;
	u64 tx_deferred;
	u64 tx_late_collision;
	u64 tx_excessive_deferred;
	u64 tx_non_tcpudp;
	u64 tx_mac_src_error;
	u64 tx_ip_src_error;
	u64 rx_bytes;
	u64 rx_good_bytes;
	u64 rx_bad_bytes;
	u64 rx_packets;
	u64 rx_good;
	u64 rx_bad;
	u64 rx_pause;
	u64 rx_control;
	u64 rx_unicast;
	u64 rx_multicast;
	u64 rx_broadcast;
	u64 rx_lt64;
	u64 rx_64;
	u64 rx_65_to_127;
	u64 rx_128_to_255;
	u64 rx_256_to_511;
	u64 rx_512_to_1023;
	u64 rx_1024_to_15xx;
	u64 rx_15xx_to_jumbo;
	u64 rx_gtjumbo;
	u64 rx_bad_lt64;
	u64 rx_bad_64_to_15xx;
	u64 rx_bad_15xx_to_jumbo;
	u64 rx_bad_gtjumbo;
	u64 rx_overflow;
	u64 rx_missed;
	u64 rx_false_carrier;
	u64 rx_symbol_error;
	u64 rx_align_error;
	u64 rx_length_error;
	u64 rx_internal_error;
	u64 rx_good_lt64;
};

/* Number of bits used in a multicast filter hash address */
#define EFX_MCAST_HASH_BITS 8

/* Number of (single-bit) entries in a multicast filter hash */
#define EFX_MCAST_HASH_ENTRIES (1 << EFX_MCAST_HASH_BITS)

/* An Efx multicast filter hash */
union efx_multicast_hash {
	u8 byte[EFX_MCAST_HASH_ENTRIES / 8];
	efx_oword_t oword[EFX_MCAST_HASH_ENTRIES / sizeof(efx_oword_t) / 8];
};

struct efx_filter_state;
struct efx_vf;
struct vfdi_status;

/**
 * struct efx_nic - an Efx NIC
 * @name: Device name (net device name or bus id before net device registered)
 * @pci_dev: The PCI device
 * @type: Controller type attributes
 * @legacy_irq: IRQ number
 * @legacy_irq_enabled: Are IRQs enabled on NIC (INT_EN_KER register)?
 * @workqueue: Workqueue for port reconfigures and the HW monitor.
 *	Work items do not hold and must not acquire RTNL.
 * @workqueue_name: Name of workqueue
 * @reset_work: Scheduled reset workitem
 * @membase_phys: Memory BAR value as physical address
 * @membase: Memory BAR value
 * @interrupt_mode: Interrupt mode
 * @timer_quantum_ns: Interrupt timer quantum, in nanoseconds
 * @irq_rx_adaptive: Adaptive IRQ moderation enabled for RX event queues
 * @irq_rx_moderation: IRQ moderation time for RX event queues
 * @msg_enable: Log message enable flags
 * @state: Device state number (%STATE_*). Serialised by the rtnl_lock.
 * @reset_pending: Bitmask for pending resets
 * @tx_queue: TX DMA queues
 * @rx_queue: RX DMA queues
 * @channel: Channels
 * @channel_name: Names for channels and their IRQs
 * @extra_channel_types: Types of extra (non-traffic) channels that
 *	should be allocated for this NIC
 * @rxq_entries: Size of receive queues requested by user.
 * @txq_entries: Size of transmit queues requested by user.
 * @txq_stop_thresh: TX queue fill level at or above which we stop it.
 * @txq_wake_thresh: TX queue fill level at or below which we wake it.
 * @tx_dc_base: Base qword address in SRAM of TX queue descriptor caches
 * @rx_dc_base: Base qword address in SRAM of RX queue descriptor caches
 * @sram_lim_qw: Qword address limit of SRAM
 * @next_buffer_table: First available buffer table id
 * @n_channels: Number of channels in use
 * @n_rx_channels: Number of channels used for RX (= number of RX queues)
 * @n_tx_channels: Number of channels used for TX
 * @rx_dma_len: Current maximum RX DMA length
 * @rx_buffer_order: Order (log2) of number of pages for each RX buffer
 * @rx_buffer_truesize: Amortised allocation size of an RX buffer,
 *	for use in sk_buff::truesize
 * @rx_hash_key: Toeplitz hash key for RSS
 * @rx_indir_table: Indirection table for RSS
 * @rx_scatter: Scatter mode enabled for receives
 * @int_error_count: Number of internal errors seen recently
 * @int_error_expire: Time at which error count will be expired
 * @irq_status: Interrupt status buffer
 * @irq_zero_count: Number of legacy IRQs seen with queue flags == 0
 * @irq_level: IRQ level/index for IRQs not triggered by an event queue
 * @selftest_work: Work item for asynchronous self-test
 * @mtd_list: List of MTDs attached to the NIC
 * @nic_data: Hardware dependent state
 * @mac_lock: MAC access lock. Protects @port_enabled, @phy_mode,
 *	efx_monitor() and efx_reconfigure_port()
 * @port_enabled: Port enabled indicator.
 *	Serialises efx_stop_all(), efx_start_all(), efx_monitor() and
 *	efx_mac_work() with kernel interfaces. Safe to read under any
 *	one of the rtnl_lock, mac_lock, or netif_tx_lock, but all three must
 *	be held to modify it.
 * @port_initialized: Port initialized?
 * @net_dev: Operating system network device. Consider holding the rtnl lock
 * @stats_buffer: DMA buffer for statistics
 * @phy_type: PHY type
 * @phy_op: PHY interface
 * @phy_data: PHY private data (including PHY-specific stats)
 * @mdio: PHY MDIO interface
 * @mdio_bus: PHY MDIO bus ID (only used by Siena)
 * @phy_mode: PHY operating mode. Serialised by @mac_lock.
 * @link_advertising: Autonegotiation advertising flags
 * @link_state: Current state of the link
 * @n_link_state_changes: Number of times the link has changed state
 * @promiscuous: Promiscuous flag. Protected by netif_tx_lock.
 * @multicast_hash: Multicast hash table
 * @wanted_fc: Wanted flow control flags
 * @fc_disable: When non-zero flow control is disabled. Typically used to
 *	ensure that network back pressure doesn't delay dma queue flushes.
 *	Serialised by the rtnl lock.
 * @mac_work: Work item for changing MAC promiscuity and multicast hash
 * @loopback_mode: Loopback status
 * @loopback_modes: Supported loopback mode bitmask
 * @loopback_selftest: Offline self-test private state
 * @drain_pending: Count of RX and TX queues that haven't been flushed and drained.
 * @rxq_flush_pending: Count of number of receive queues that need to be flushed.
 *	Decremented when the efx_flush_rx_queue() is called.
 * @rxq_flush_outstanding: Count of number of RX flushes started but not yet
 *	completed (either success or failure). Not used when MCDI is used to
 *	flush receive queues.
 * @flush_wq: wait queue used by efx_nic_flush_queues() to wait for flush completions.
 * @vf: Array of &struct efx_vf objects.
 * @vf_count: Number of VFs intended to be enabled.
 * @vf_init_count: Number of VFs that have been fully initialised.
 * @vi_scale: log2 number of vnics per VF.
 * @vf_buftbl_base: The zeroth buffer table index used to back VF queues.
 * @vfdi_status: Common VFDI status page to be dmad to VF address space.
 * @local_addr_list: List of local addresses. Protected by %local_lock.
 * @local_page_list: List of DMA addressable pages used to broadcast
 *	%local_addr_list. Protected by %local_lock.
 * @local_lock: Mutex protecting %local_addr_list and %local_page_list.
 * @peer_work: Work item to broadcast peer addresses to VMs.
 * @ptp_data: PTP state data
 * @monitor_work: Hardware monitor workitem
 * @biu_lock: BIU (bus interface unit) lock
 * @last_irq_cpu: Last CPU to handle a possible test interrupt.  This
 *	field is used by efx_test_interrupts() to verify that an
 *	interrupt has occurred.
 * @n_rx_nodesc_drop_cnt: RX no descriptor drop count
 * @mac_stats: MAC statistics. These include all statistics the MACs
 *	can provide.  Generic code converts these into a standard
 *	&struct net_device_stats.
 * @stats_lock: Statistics update lock. Serialises statistics fetches
 *	and access to @mac_stats.
 *
 * This is stored in the private area of the &struct net_device.
 */
struct efx_nic {
	/* The following fields should be written very rarely */

	char name[IFNAMSIZ];
	struct pci_dev *pci_dev;
	unsigned int port_num;
	const struct efx_nic_type *type;
	int legacy_irq;
	bool legacy_irq_enabled;
	bool eeh_disabled_legacy_irq;
	struct workqueue_struct *workqueue;
	char workqueue_name[16];
	struct work_struct reset_work;
	resource_size_t membase_phys;
	void __iomem *membase;

	enum efx_int_mode interrupt_mode;
	unsigned int timer_quantum_ns;
	bool irq_rx_adaptive;
	unsigned int irq_rx_moderation;
	u32 msg_enable;

	enum nic_state state;
	unsigned long reset_pending;

	struct efx_channel *channel[EFX_MAX_CHANNELS];
	char channel_name[EFX_MAX_CHANNELS][IFNAMSIZ + 6];
	const struct efx_channel_type *
	extra_channel_type[EFX_MAX_EXTRA_CHANNELS];

	unsigned rxq_entries;
	unsigned txq_entries;
	unsigned int txq_stop_thresh;
	unsigned int txq_wake_thresh;

	unsigned tx_dc_base;
	unsigned rx_dc_base;
	unsigned sram_lim_qw;
	unsigned next_buffer_table;
	unsigned n_channels;
	unsigned n_rx_channels;
	unsigned rss_spread;
	unsigned tx_channel_offset;
	unsigned n_tx_channels;
	unsigned int rx_dma_len;
	unsigned int rx_buffer_order;
	unsigned int rx_buffer_truesize;
	unsigned int rx_page_buf_step;
	unsigned int rx_bufs_per_page;
	unsigned int rx_pages_per_batch;
	u8 rx_hash_key[40];
	u32 rx_indir_table[128];
	bool rx_scatter;

	unsigned int_error_count;
	unsigned long int_error_expire;

	struct efx_buffer irq_status;
	unsigned irq_zero_count;
	unsigned irq_level;
	struct delayed_work selftest_work;

#ifdef CONFIG_SFC_MTD
	struct list_head mtd_list;
#endif

	void *nic_data;

	struct mutex mac_lock;
	struct work_struct mac_work;
	bool port_enabled;

	bool port_initialized;
	struct net_device *net_dev;

	struct efx_buffer stats_buffer;

	unsigned int phy_type;
	const struct efx_phy_operations *phy_op;
	void *phy_data;
	struct mdio_if_info mdio;
	unsigned int mdio_bus;
	enum efx_phy_mode phy_mode;

	u32 link_advertising;
	struct efx_link_state link_state;
	unsigned int n_link_state_changes;

	bool promiscuous;
	union efx_multicast_hash multicast_hash;
	u8 wanted_fc;
	unsigned fc_disable;

	atomic_t rx_reset;
	enum efx_loopback_mode loopback_mode;
	u64 loopback_modes;

	void *loopback_selftest;

	struct efx_filter_state *filter_state;

	atomic_t drain_pending;
	atomic_t rxq_flush_pending;
	atomic_t rxq_flush_outstanding;
	wait_queue_head_t flush_wq;

#ifdef CONFIG_SFC_SRIOV
	struct efx_channel *vfdi_channel;
	struct efx_vf *vf;
	unsigned vf_count;
	unsigned vf_init_count;
	unsigned vi_scale;
	unsigned vf_buftbl_base;
	struct efx_buffer vfdi_status;
	struct list_head local_addr_list;
	struct list_head local_page_list;
	struct mutex local_lock;
	struct work_struct peer_work;
#endif

	struct efx_ptp_data *ptp_data;

	/* The following fields may be written more often */

	struct delayed_work monitor_work ____cacheline_aligned_in_smp;
	spinlock_t biu_lock;
	int last_irq_cpu;
	unsigned n_rx_nodesc_drop_cnt;
	struct efx_mac_stats mac_stats;
	spinlock_t stats_lock;
};

static inline int efx_dev_registered(struct efx_nic *efx)
{
	return efx->net_dev->reg_state == NETREG_REGISTERED;
}

static inline unsigned int efx_port_num(struct efx_nic *efx)
{
	return efx->port_num;
}

/**
 * struct efx_nic_type - Efx device type definition
 * @probe: Probe the controller
 * @remove: Free resources allocated by probe()
 * @init: Initialise the controller
 * @dimension_resources: Dimension controller resources (buffer table,
 *	and VIs once the available interrupt resources are clear)
 * @fini: Shut down the controller
 * @monitor: Periodic function for polling link state and hardware monitor
 * @map_reset_reason: Map ethtool reset reason to a reset method
 * @map_reset_flags: Map ethtool reset flags to a reset method, if possible
 * @reset: Reset the controller hardware and possibly the PHY.  This will
 *	be called while the controller is uninitialised.
 * @probe_port: Probe the MAC and PHY
 * @remove_port: Free resources allocated by probe_port()
 * @handle_global_event: Handle a "global" event (may be %NULL)
 * @prepare_flush: Prepare the hardware for flushing the DMA queues
 * @finish_flush: Clean up after flushing the DMA queues
 * @update_stats: Update statistics not provided by event handling
 * @start_stats: Start the regular fetching of statistics
 * @stop_stats: Stop the regular fetching of statistics
 * @set_id_led: Set state of identifying LED or revert to automatic function
 * @push_irq_moderation: Apply interrupt moderation value
 * @reconfigure_port: Push loopback/power/txdis changes to the MAC and PHY
 * @prepare_enable_fc_tx: Prepare MAC to enable pause frame TX (may be %NULL)
 * @reconfigure_mac: Push MAC address, MTU, flow control and filter settings
 *	to the hardware.  Serialised by the mac_lock.
 * @check_mac_fault: Check MAC fault state. True if fault present.
 * @get_wol: Get WoL configuration from driver state
 * @set_wol: Push WoL configuration to the NIC
 * @resume_wol: Synchronise WoL state between driver and MC (e.g. after resume)
 * @test_chip: Test registers.  Should use efx_nic_test_registers(), and is
 *	expected to reset the NIC.
 * @test_nvram: Test validity of NVRAM contents
 * @revision: Hardware architecture revision
 * @mem_map_size: Memory BAR mapped size
 * @txd_ptr_tbl_base: TX descriptor ring base address
 * @rxd_ptr_tbl_base: RX descriptor ring base address
 * @buf_tbl_base: Buffer table base address
 * @evq_ptr_tbl_base: Event queue pointer table base address
 * @evq_rptr_tbl_base: Event queue read-pointer table base address
 * @max_dma_mask: Maximum possible DMA mask
 * @rx_buffer_hash_size: Size of hash at start of RX packet
 * @rx_buffer_padding: Size of padding at end of RX packet
 * @can_rx_scatter: NIC is able to scatter packet to multiple buffers
 * @max_interrupt_mode: Highest capability interrupt mode supported
 *	from &enum efx_init_mode.
 * @phys_addr_channels: Number of channels with physically addressed
 *	descriptors
 * @timer_period_max: Maximum period of interrupt timer (in ticks)
 * @offload_features: net_device feature flags for protocol offload
 *	features implemented in hardware
 */
struct efx_nic_type {
	int (*probe)(struct efx_nic *efx);
	void (*remove)(struct efx_nic *efx);
	int (*init)(struct efx_nic *efx);
	void (*dimension_resources)(struct efx_nic *efx);
	void (*fini)(struct efx_nic *efx);
	void (*monitor)(struct efx_nic *efx);
	enum reset_type (*map_reset_reason)(enum reset_type reason);
	int (*map_reset_flags)(u32 *flags);
	int (*reset)(struct efx_nic *efx, enum reset_type method);
	int (*probe_port)(struct efx_nic *efx);
	void (*remove_port)(struct efx_nic *efx);
	bool (*handle_global_event)(struct efx_channel *channel, efx_qword_t *);
	void (*prepare_flush)(struct efx_nic *efx);
	void (*finish_flush)(struct efx_nic *efx);
	void (*update_stats)(struct efx_nic *efx);
	void (*start_stats)(struct efx_nic *efx);
	void (*stop_stats)(struct efx_nic *efx);
	void (*set_id_led)(struct efx_nic *efx, enum efx_led_mode mode);
	void (*push_irq_moderation)(struct efx_channel *channel);
	int (*reconfigure_port)(struct efx_nic *efx);
	void (*prepare_enable_fc_tx)(struct efx_nic *efx);
	int (*reconfigure_mac)(struct efx_nic *efx);
	bool (*check_mac_fault)(struct efx_nic *efx);
	void (*get_wol)(struct efx_nic *efx, struct ethtool_wolinfo *wol);
	int (*set_wol)(struct efx_nic *efx, u32 type);
	void (*resume_wol)(struct efx_nic *efx);
	int (*test_chip)(struct efx_nic *efx, struct efx_self_tests *tests);
	int (*test_nvram)(struct efx_nic *efx);

	int revision;
	unsigned int mem_map_size;
	unsigned int txd_ptr_tbl_base;
	unsigned int rxd_ptr_tbl_base;
	unsigned int buf_tbl_base;
	unsigned int evq_ptr_tbl_base;
	unsigned int evq_rptr_tbl_base;
	u64 max_dma_mask;
	unsigned int rx_buffer_hash_size;
	unsigned int rx_buffer_padding;
	bool can_rx_scatter;
	unsigned int max_interrupt_mode;
	unsigned int phys_addr_channels;
	unsigned int timer_period_max;
	netdev_features_t offload_features;
};

/**************************************************************************
 *
 * Prototypes and inline functions
 *
 *************************************************************************/

static inline struct efx_channel *
efx_get_channel(struct efx_nic *efx, unsigned index)
{
	EFX_BUG_ON_PARANOID(index >= efx->n_channels);
	return efx->channel[index];
}

/* Iterate over all used channels */
#define efx_for_each_channel(_channel, _efx)				\
	for (_channel = (_efx)->channel[0];				\
	     _channel;							\
	     _channel = (_channel->channel + 1 < (_efx)->n_channels) ?	\
		     (_efx)->channel[_channel->channel + 1] : NULL)

/* Iterate over all used channels in reverse */
#define efx_for_each_channel_rev(_channel, _efx)			\
	for (_channel = (_efx)->channel[(_efx)->n_channels - 1];	\
	     _channel;							\
	     _channel = _channel->channel ?				\
		     (_efx)->channel[_channel->channel - 1] : NULL)

static inline struct efx_tx_queue *
efx_get_tx_queue(struct efx_nic *efx, unsigned index, unsigned type)
{
	EFX_BUG_ON_PARANOID(index >= efx->n_tx_channels ||
			    type >= EFX_TXQ_TYPES);
	return &efx->channel[efx->tx_channel_offset + index]->tx_queue[type];
}

static inline bool efx_channel_has_tx_queues(struct efx_channel *channel)
{
	return channel->channel - channel->efx->tx_channel_offset <
		channel->efx->n_tx_channels;
}

static inline struct efx_tx_queue *
efx_channel_get_tx_queue(struct efx_channel *channel, unsigned type)
{
	EFX_BUG_ON_PARANOID(!efx_channel_has_tx_queues(channel) ||
			    type >= EFX_TXQ_TYPES);
	return &channel->tx_queue[type];
}

static inline bool efx_tx_queue_used(struct efx_tx_queue *tx_queue)
{
	return !(tx_queue->efx->net_dev->num_tc < 2 &&
		 tx_queue->queue & EFX_TXQ_TYPE_HIGHPRI);
}

/* Iterate over all TX queues belonging to a channel */
#define efx_for_each_channel_tx_queue(_tx_queue, _channel)		\
	if (!efx_channel_has_tx_queues(_channel))			\
		;							\
	else								\
		for (_tx_queue = (_channel)->tx_queue;			\
		     _tx_queue < (_channel)->tx_queue + EFX_TXQ_TYPES && \
			     efx_tx_queue_used(_tx_queue);		\
		     _tx_queue++)

/* Iterate over all possible TX queues belonging to a channel */
#define efx_for_each_possible_channel_tx_queue(_tx_queue, _channel)	\
	if (!efx_channel_has_tx_queues(_channel))			\
		;							\
	else								\
		for (_tx_queue = (_channel)->tx_queue;			\
		     _tx_queue < (_channel)->tx_queue + EFX_TXQ_TYPES;	\
		     _tx_queue++)

static inline bool efx_channel_has_rx_queue(struct efx_channel *channel)
{
	return channel->rx_queue.core_index >= 0;
}

static inline struct efx_rx_queue *
efx_channel_get_rx_queue(struct efx_channel *channel)
{
	EFX_BUG_ON_PARANOID(!efx_channel_has_rx_queue(channel));
	return &channel->rx_queue;
}

/* Iterate over all RX queues belonging to a channel */
#define efx_for_each_channel_rx_queue(_rx_queue, _channel)		\
	if (!efx_channel_has_rx_queue(_channel))			\
		;							\
	else								\
		for (_rx_queue = &(_channel)->rx_queue;			\
		     _rx_queue;						\
		     _rx_queue = NULL)

static inline struct efx_channel *
efx_rx_queue_channel(struct efx_rx_queue *rx_queue)
{
	return container_of(rx_queue, struct efx_channel, rx_queue);
}

static inline int efx_rx_queue_index(struct efx_rx_queue *rx_queue)
{
	return efx_rx_queue_channel(rx_queue)->channel;
}

/* Returns a pointer to the specified receive buffer in the RX
 * descriptor queue.
 */
static inline struct efx_rx_buffer *efx_rx_buffer(struct efx_rx_queue *rx_queue,
						  unsigned int index)
{
	return &rx_queue->buffer[index];
}


/**
 * EFX_MAX_FRAME_LEN - calculate maximum frame length
 *
 * This calculates the maximum frame length that will be used for a
 * given MTU.  The frame length will be equal to the MTU plus a
 * constant amount of header space and padding.  This is the quantity
 * that the net driver will program into the MAC as the maximum frame
 * length.
 *
 * The 10G MAC requires 8-byte alignment on the frame
 * length, so we round up to the nearest 8.
 *
 * Re-clocking by the XGXS on RX can reduce an IPG to 32 bits (half an
 * XGMII cycle).  If the frame length reaches the maximum value in the
 * same cycle, the XMAC can miss the IPG altogether.  We work around
 * this by adding a further 16 bytes.
 */
#define EFX_MAX_FRAME_LEN(mtu) \
	((((mtu) + ETH_HLEN + VLAN_HLEN + 4/* FCS */ + 7) & ~7) + 16)

static inline bool efx_xmit_with_hwtstamp(struct sk_buff *skb)
{
	return skb_shinfo(skb)->tx_flags & SKBTX_HW_TSTAMP;
}
static inline void efx_xmit_hwtstamp_pending(struct sk_buff *skb)
{
	skb_shinfo(skb)->tx_flags |= SKBTX_IN_PROGRESS;
}

#endif /* EFX_NET_DRIVER_H */