summaryrefslogtreecommitdiffstats
path: root/kernel/drivers/net/ethernet/sfc/selftest.c
blob: b605dfd5c7bc7146600908b1c7a40f79b28dfd53 (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
/****************************************************************************
 * Driver for Solarflare network controllers and boards
 * Copyright 2005-2006 Fen Systems Ltd.
 * Copyright 2006-2012 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.
 */

#include <linux/netdevice.h>
#include <linux/module.h>
#include <linux/delay.h>
#include <linux/kernel_stat.h>
#include <linux/pci.h>
#include <linux/ethtool.h>
#include <linux/ip.h>
#include <linux/in.h>
#include <linux/udp.h>
#include <linux/rtnetlink.h>
#include <linux/slab.h>
#include "net_driver.h"
#include "efx.h"
#include "nic.h"
#include "selftest.h"
#include "workarounds.h"

/* IRQ latency can be enormous because:
 * - All IRQs may be disabled on a CPU for a *long* time by e.g. a
 *   slow serial console or an old IDE driver doing error recovery
 * - The PREEMPT_RT patches mostly deal with this, but also allow a
 *   tasklet or normal task to be given higher priority than our IRQ
 *   threads
 * Try to avoid blaming the hardware for this.
 */
#define IRQ_TIMEOUT HZ

/*
 * Loopback test packet structure
 *
 * The self-test should stress every RSS vector, and unfortunately
 * Falcon only performs RSS on TCP/UDP packets.
 */
struct efx_loopback_payload {
	struct ethhdr header;
	struct iphdr ip;
	struct udphdr udp;
	__be16 iteration;
	char msg[64];
} __packed;

/* Loopback test source MAC address */
static const u8 payload_source[ETH_ALEN] __aligned(2) = {
	0x00, 0x0f, 0x53, 0x1b, 0x1b, 0x1b,
};

static const char payload_msg[] =
	"Hello world! This is an Efx loopback test in progress!";

/* Interrupt mode names */
static const unsigned int efx_interrupt_mode_max = EFX_INT_MODE_MAX;
static const char *const efx_interrupt_mode_names[] = {
	[EFX_INT_MODE_MSIX]   = "MSI-X",
	[EFX_INT_MODE_MSI]    = "MSI",
	[EFX_INT_MODE_LEGACY] = "legacy",
};
#define INT_MODE(efx) \
	STRING_TABLE_LOOKUP(efx->interrupt_mode, efx_interrupt_mode)

/**
 * efx_loopback_state - persistent state during a loopback selftest
 * @flush:		Drop all packets in efx_loopback_rx_packet
 * @packet_count:	Number of packets being used in this test
 * @skbs:		An array of skbs transmitted
 * @offload_csum:	Checksums are being offloaded
 * @rx_good:		RX good packet count
 * @rx_bad:		RX bad packet count
 * @payload:		Payload used in tests
 */
struct efx_loopback_state {
	bool flush;
	int packet_count;
	struct sk_buff **skbs;
	bool offload_csum;
	atomic_t rx_good;
	atomic_t rx_bad;
	struct efx_loopback_payload payload;
};

/* How long to wait for all the packets to arrive (in ms) */
#define LOOPBACK_TIMEOUT_MS 1000

/**************************************************************************
 *
 * MII, NVRAM and register tests
 *
 **************************************************************************/

static int efx_test_phy_alive(struct efx_nic *efx, struct efx_self_tests *tests)
{
	int rc = 0;

	if (efx->phy_op->test_alive) {
		rc = efx->phy_op->test_alive(efx);
		tests->phy_alive = rc ? -1 : 1;
	}

	return rc;
}

static int efx_test_nvram(struct efx_nic *efx, struct efx_self_tests *tests)
{
	int rc = 0;

	if (efx->type->test_nvram) {
		rc = efx->type->test_nvram(efx);
		tests->nvram = rc ? -1 : 1;
	}

	return rc;
}

/**************************************************************************
 *
 * Interrupt and event queue testing
 *
 **************************************************************************/

/* Test generation and receipt of interrupts */
static int efx_test_interrupts(struct efx_nic *efx,
			       struct efx_self_tests *tests)
{
	unsigned long timeout, wait;
	int cpu;

	netif_dbg(efx, drv, efx->net_dev, "testing interrupts\n");
	tests->interrupt = -1;

	efx_nic_irq_test_start(efx);
	timeout = jiffies + IRQ_TIMEOUT;
	wait = 1;

	/* Wait for arrival of test interrupt. */
	netif_dbg(efx, drv, efx->net_dev, "waiting for test interrupt\n");
	do {
		schedule_timeout_uninterruptible(wait);
		cpu = efx_nic_irq_test_irq_cpu(efx);
		if (cpu >= 0)
			goto success;
		wait *= 2;
	} while (time_before(jiffies, timeout));

	netif_err(efx, drv, efx->net_dev, "timed out waiting for interrupt\n");
	return -ETIMEDOUT;

 success:
	netif_dbg(efx, drv, efx->net_dev, "%s test interrupt seen on CPU%d\n",
		  INT_MODE(efx), cpu);
	tests->interrupt = 1;
	return 0;
}

/* Test generation and receipt of interrupting events */
static int efx_test_eventq_irq(struct efx_nic *efx,
			       struct efx_self_tests *tests)
{
	struct efx_channel *channel;
	unsigned int read_ptr[EFX_MAX_CHANNELS];
	unsigned long napi_ran = 0, dma_pend = 0, int_pend = 0;
	unsigned long timeout, wait;

	BUILD_BUG_ON(EFX_MAX_CHANNELS > BITS_PER_LONG);

	efx_for_each_channel(channel, efx) {
		read_ptr[channel->channel] = channel->eventq_read_ptr;
		set_bit(channel->channel, &dma_pend);
		set_bit(channel->channel, &int_pend);
		efx_nic_event_test_start(channel);
	}

	timeout = jiffies + IRQ_TIMEOUT;
	wait = 1;

	/* Wait for arrival of interrupts.  NAPI processing may or may
	 * not complete in time, but we can cope in any case.
	 */
	do {
		schedule_timeout_uninterruptible(wait);

		efx_for_each_channel(channel, efx) {
			efx_stop_eventq(channel);
			if (channel->eventq_read_ptr !=
			    read_ptr[channel->channel]) {
				set_bit(channel->channel, &napi_ran);
				clear_bit(channel->channel, &dma_pend);
				clear_bit(channel->channel, &int_pend);
			} else {
				if (efx_nic_event_present(channel))
					clear_bit(channel->channel, &dma_pend);
				if (efx_nic_event_test_irq_cpu(channel) >= 0)
					clear_bit(channel->channel, &int_pend);
			}
			efx_start_eventq(channel);
		}

		wait *= 2;
	} while ((dma_pend || int_pend) && time_before(jiffies, timeout));

	efx_for_each_channel(channel, efx) {
		bool dma_seen = !test_bit(channel->channel, &dma_pend);
		bool int_seen = !test_bit(channel->channel, &int_pend);

		tests->eventq_dma[channel->channel] = dma_seen ? 1 : -1;
		tests->eventq_int[channel->channel] = int_seen ? 1 : -1;

		if (dma_seen && int_seen) {
			netif_dbg(efx, drv, efx->net_dev,
				  "channel %d event queue passed (with%s NAPI)\n",
				  channel->channel,
				  test_bit(channel->channel, &napi_ran) ?
				  "" : "out");
		} else {
			/* Report failure and whether either interrupt or DMA
			 * worked
			 */
			netif_err(efx, drv, efx->net_dev,
				  "channel %d timed out waiting for event queue\n",
				  channel->channel);
			if (int_seen)
				netif_err(efx, drv, efx->net_dev,
					  "channel %d saw interrupt "
					  "during event queue test\n",
					  channel->channel);
			if (dma_seen)
				netif_err(efx, drv, efx->net_dev,
					  "channel %d event was generated, but "
					  "failed to trigger an interrupt\n",
					  channel->channel);
		}
	}

	return (dma_pend || int_pend) ? -ETIMEDOUT : 0;
}

static int efx_test_phy(struct efx_nic *efx, struct efx_self_tests *tests,
			unsigned flags)
{
	int rc;

	if (!efx->phy_op->run_tests)
		return 0;

	mutex_lock(&efx->mac_lock);
	rc = efx->phy_op->run_tests(efx, tests->phy_ext, flags);
	mutex_unlock(&efx->mac_lock);
	return rc;
}

/**************************************************************************
 *
 * Loopback testing
 * NB Only one loopback test can be executing concurrently.
 *
 **************************************************************************/

/* Loopback test RX callback
 * This is called for each received packet during loopback testing.
 */
void efx_loopback_rx_packet(struct efx_nic *efx,
			    const char *buf_ptr, int pkt_len)
{
	struct efx_loopback_state *state = efx->loopback_selftest;
	struct efx_loopback_payload *received;
	struct efx_loopback_payload *payload;

	BUG_ON(!buf_ptr);

	/* If we are just flushing, then drop the packet */
	if ((state == NULL) || state->flush)
		return;

	payload = &state->payload;

	received = (struct efx_loopback_payload *) buf_ptr;
	received->ip.saddr = payload->ip.saddr;
	if (state->offload_csum)
		received->ip.check = payload->ip.check;

	/* Check that header exists */
	if (pkt_len < sizeof(received->header)) {
		netif_err(efx, drv, efx->net_dev,
			  "saw runt RX packet (length %d) in %s loopback "
			  "test\n", pkt_len, LOOPBACK_MODE(efx));
		goto err;
	}

	/* Check that the ethernet header exists */
	if (memcmp(&received->header, &payload->header, ETH_HLEN) != 0) {
		netif_err(efx, drv, efx->net_dev,
			  "saw non-loopback RX packet in %s loopback test\n",
			  LOOPBACK_MODE(efx));
		goto err;
	}

	/* Check packet length */
	if (pkt_len != sizeof(*payload)) {
		netif_err(efx, drv, efx->net_dev,
			  "saw incorrect RX packet length %d (wanted %d) in "
			  "%s loopback test\n", pkt_len, (int)sizeof(*payload),
			  LOOPBACK_MODE(efx));
		goto err;
	}

	/* Check that IP header matches */
	if (memcmp(&received->ip, &payload->ip, sizeof(payload->ip)) != 0) {
		netif_err(efx, drv, efx->net_dev,
			  "saw corrupted IP header in %s loopback test\n",
			  LOOPBACK_MODE(efx));
		goto err;
	}

	/* Check that msg and padding matches */
	if (memcmp(&received->msg, &payload->msg, sizeof(received->msg)) != 0) {
		netif_err(efx, drv, efx->net_dev,
			  "saw corrupted RX packet in %s loopback test\n",
			  LOOPBACK_MODE(efx));
		goto err;
	}

	/* Check that iteration matches */
	if (received->iteration != payload->iteration) {
		netif_err(efx, drv, efx->net_dev,
			  "saw RX packet from iteration %d (wanted %d) in "
			  "%s loopback test\n", ntohs(received->iteration),
			  ntohs(payload->iteration), LOOPBACK_MODE(efx));
		goto err;
	}

	/* Increase correct RX count */
	netif_vdbg(efx, drv, efx->net_dev,
		   "got loopback RX in %s loopback test\n", LOOPBACK_MODE(efx));

	atomic_inc(&state->rx_good);
	return;

 err:
#ifdef DEBUG
	if (atomic_read(&state->rx_bad) == 0) {
		netif_err(efx, drv, efx->net_dev, "received packet:\n");
		print_hex_dump(KERN_ERR, "", DUMP_PREFIX_OFFSET, 0x10, 1,
			       buf_ptr, pkt_len, 0);
		netif_err(efx, drv, efx->net_dev, "expected packet:\n");
		print_hex_dump(KERN_ERR, "", DUMP_PREFIX_OFFSET, 0x10, 1,
			       &state->payload, sizeof(state->payload), 0);
	}
#endif
	atomic_inc(&state->rx_bad);
}

/* Initialise an efx_selftest_state for a new iteration */
static void efx_iterate_state(struct efx_nic *efx)
{
	struct efx_loopback_state *state = efx->loopback_selftest;
	struct net_device *net_dev = efx->net_dev;
	struct efx_loopback_payload *payload = &state->payload;

	/* Initialise the layerII header */
	ether_addr_copy((u8 *)&payload->header.h_dest, net_dev->dev_addr);
	ether_addr_copy((u8 *)&payload->header.h_source, payload_source);
	payload->header.h_proto = htons(ETH_P_IP);

	/* saddr set later and used as incrementing count */
	payload->ip.daddr = htonl(INADDR_LOOPBACK);
	payload->ip.ihl = 5;
	payload->ip.check = (__force __sum16) htons(0xdead);
	payload->ip.tot_len = htons(sizeof(*payload) - sizeof(struct ethhdr));
	payload->ip.version = IPVERSION;
	payload->ip.protocol = IPPROTO_UDP;

	/* Initialise udp header */
	payload->udp.source = 0;
	payload->udp.len = htons(sizeof(*payload) - sizeof(struct ethhdr) -
				 sizeof(struct iphdr));
	payload->udp.check = 0;	/* checksum ignored */

	/* Fill out payload */
	payload->iteration = htons(ntohs(payload->iteration) + 1);
	memcpy(&payload->msg, payload_msg, sizeof(payload_msg));

	/* Fill out remaining state members */
	atomic_set(&state->rx_good, 0);
	atomic_set(&state->rx_bad, 0);
	smp_wmb();
}

static int efx_begin_loopback(struct efx_tx_queue *tx_queue)
{
	struct efx_nic *efx = tx_queue->efx;
	struct efx_loopback_state *state = efx->loopback_selftest;
	struct efx_loopback_payload *payload;
	struct sk_buff *skb;
	int i;
	netdev_tx_t rc;

	/* Transmit N copies of buffer */
	for (i = 0; i < state->packet_count; i++) {
		/* Allocate an skb, holding an extra reference for
		 * transmit completion counting */
		skb = alloc_skb(sizeof(state->payload), GFP_KERNEL);
		if (!skb)
			return -ENOMEM;
		state->skbs[i] = skb;
		skb_get(skb);

		/* Copy the payload in, incrementing the source address to
		 * exercise the rss vectors */
		payload = ((struct efx_loopback_payload *)
			   skb_put(skb, sizeof(state->payload)));
		memcpy(payload, &state->payload, sizeof(state->payload));
		payload->ip.saddr = htonl(INADDR_LOOPBACK | (i << 2));

		/* Ensure everything we've written is visible to the
		 * interrupt handler. */
		smp_wmb();

		netif_tx_lock_bh(efx->net_dev);
		rc = efx_enqueue_skb(tx_queue, skb);
		netif_tx_unlock_bh(efx->net_dev);

		if (rc != NETDEV_TX_OK) {
			netif_err(efx, drv, efx->net_dev,
				  "TX queue %d could not transmit packet %d of "
				  "%d in %s loopback test\n", tx_queue->queue,
				  i + 1, state->packet_count,
				  LOOPBACK_MODE(efx));

			/* Defer cleaning up the other skbs for the caller */
			kfree_skb(skb);
			return -EPIPE;
		}
	}

	return 0;
}

static int efx_poll_loopback(struct efx_nic *efx)
{
	struct efx_loopback_state *state = efx->loopback_selftest;

	return atomic_read(&state->rx_good) == state->packet_count;
}

static int efx_end_loopback(struct efx_tx_queue *tx_queue,
			    struct efx_loopback_self_tests *lb_tests)
{
	struct efx_nic *efx = tx_queue->efx;
	struct efx_loopback_state *state = efx->loopback_selftest;
	struct sk_buff *skb;
	int tx_done = 0, rx_good, rx_bad;
	int i, rc = 0;

	netif_tx_lock_bh(efx->net_dev);

	/* Count the number of tx completions, and decrement the refcnt. Any
	 * skbs not already completed will be free'd when the queue is flushed */
	for (i = 0; i < state->packet_count; i++) {
		skb = state->skbs[i];
		if (skb && !skb_shared(skb))
			++tx_done;
		dev_kfree_skb(skb);
	}

	netif_tx_unlock_bh(efx->net_dev);

	/* Check TX completion and received packet counts */
	rx_good = atomic_read(&state->rx_good);
	rx_bad = atomic_read(&state->rx_bad);
	if (tx_done != state->packet_count) {
		/* Don't free the skbs; they will be picked up on TX
		 * overflow or channel teardown.
		 */
		netif_err(efx, drv, efx->net_dev,
			  "TX queue %d saw only %d out of an expected %d "
			  "TX completion events in %s loopback test\n",
			  tx_queue->queue, tx_done, state->packet_count,
			  LOOPBACK_MODE(efx));
		rc = -ETIMEDOUT;
		/* Allow to fall through so we see the RX errors as well */
	}

	/* We may always be up to a flush away from our desired packet total */
	if (rx_good != state->packet_count) {
		netif_dbg(efx, drv, efx->net_dev,
			  "TX queue %d saw only %d out of an expected %d "
			  "received packets in %s loopback test\n",
			  tx_queue->queue, rx_good, state->packet_count,
			  LOOPBACK_MODE(efx));
		rc = -ETIMEDOUT;
		/* Fall through */
	}

	/* Update loopback test structure */
	lb_tests->tx_sent[tx_queue->queue] += state->packet_count;
	lb_tests->tx_done[tx_queue->queue] += tx_done;
	lb_tests->rx_good += rx_good;
	lb_tests->rx_bad += rx_bad;

	return rc;
}

static int
efx_test_loopback(struct efx_tx_queue *tx_queue,
		  struct efx_loopback_self_tests *lb_tests)
{
	struct efx_nic *efx = tx_queue->efx;
	struct efx_loopback_state *state = efx->loopback_selftest;
	int i, begin_rc, end_rc;

	for (i = 0; i < 3; i++) {
		/* Determine how many packets to send */
		state->packet_count = efx->txq_entries / 3;
		state->packet_count = min(1 << (i << 2), state->packet_count);
		state->skbs = kcalloc(state->packet_count,
				      sizeof(state->skbs[0]), GFP_KERNEL);
		if (!state->skbs)
			return -ENOMEM;
		state->flush = false;

		netif_dbg(efx, drv, efx->net_dev,
			  "TX queue %d testing %s loopback with %d packets\n",
			  tx_queue->queue, LOOPBACK_MODE(efx),
			  state->packet_count);

		efx_iterate_state(efx);
		begin_rc = efx_begin_loopback(tx_queue);

		/* This will normally complete very quickly, but be
		 * prepared to wait much longer. */
		msleep(1);
		if (!efx_poll_loopback(efx)) {
			msleep(LOOPBACK_TIMEOUT_MS);
			efx_poll_loopback(efx);
		}

		end_rc = efx_end_loopback(tx_queue, lb_tests);
		kfree(state->skbs);

		if (begin_rc || end_rc) {
			/* Wait a while to ensure there are no packets
			 * floating around after a failure. */
			schedule_timeout_uninterruptible(HZ / 10);
			return begin_rc ? begin_rc : end_rc;
		}
	}

	netif_dbg(efx, drv, efx->net_dev,
		  "TX queue %d passed %s loopback test with a burst length "
		  "of %d packets\n", tx_queue->queue, LOOPBACK_MODE(efx),
		  state->packet_count);

	return 0;
}

/* Wait for link up. On Falcon, we would prefer to rely on efx_monitor, but
 * any contention on the mac lock (via e.g. efx_mac_mcast_work) causes it
 * to delay and retry. Therefore, it's safer to just poll directly. Wait
 * for link up and any faults to dissipate. */
static int efx_wait_for_link(struct efx_nic *efx)
{
	struct efx_link_state *link_state = &efx->link_state;
	int count, link_up_count = 0;
	bool link_up;

	for (count = 0; count < 40; count++) {
		schedule_timeout_uninterruptible(HZ / 10);

		if (efx->type->monitor != NULL) {
			mutex_lock(&efx->mac_lock);
			efx->type->monitor(efx);
			mutex_unlock(&efx->mac_lock);
		}

		mutex_lock(&efx->mac_lock);
		link_up = link_state->up;
		if (link_up)
			link_up = !efx->type->check_mac_fault(efx);
		mutex_unlock(&efx->mac_lock);

		if (link_up) {
			if (++link_up_count == 2)
				return 0;
		} else {
			link_up_count = 0;
		}
	}

	return -ETIMEDOUT;
}

static int efx_test_loopbacks(struct efx_nic *efx, struct efx_self_tests *tests,
			      unsigned int loopback_modes)
{
	enum efx_loopback_mode mode;
	struct efx_loopback_state *state;
	struct efx_channel *channel =
		efx_get_channel(efx, efx->tx_channel_offset);
	struct efx_tx_queue *tx_queue;
	int rc = 0;

	/* Set the port loopback_selftest member. From this point on
	 * all received packets will be dropped. Mark the state as
	 * "flushing" so all inflight packets are dropped */
	state = kzalloc(sizeof(*state), GFP_KERNEL);
	if (state == NULL)
		return -ENOMEM;
	BUG_ON(efx->loopback_selftest);
	state->flush = true;
	efx->loopback_selftest = state;

	/* Test all supported loopback modes */
	for (mode = LOOPBACK_NONE; mode <= LOOPBACK_TEST_MAX; mode++) {
		if (!(loopback_modes & (1 << mode)))
			continue;

		/* Move the port into the specified loopback mode. */
		state->flush = true;
		mutex_lock(&efx->mac_lock);
		efx->loopback_mode = mode;
		rc = __efx_reconfigure_port(efx);
		mutex_unlock(&efx->mac_lock);
		if (rc) {
			netif_err(efx, drv, efx->net_dev,
				  "unable to move into %s loopback\n",
				  LOOPBACK_MODE(efx));
			goto out;
		}

		rc = efx_wait_for_link(efx);
		if (rc) {
			netif_err(efx, drv, efx->net_dev,
				  "loopback %s never came up\n",
				  LOOPBACK_MODE(efx));
			goto out;
		}

		/* Test all enabled types of TX queue */
		efx_for_each_channel_tx_queue(tx_queue, channel) {
			state->offload_csum = (tx_queue->queue &
					       EFX_TXQ_TYPE_OFFLOAD);
			rc = efx_test_loopback(tx_queue,
					       &tests->loopback[mode]);
			if (rc)
				goto out;
		}
	}

 out:
	/* Remove the flush. The caller will remove the loopback setting */
	state->flush = true;
	efx->loopback_selftest = NULL;
	wmb();
	kfree(state);

	return rc;
}

/**************************************************************************
 *
 * Entry point
 *
 *************************************************************************/

int efx_selftest(struct efx_nic *efx, struct efx_self_tests *tests,
		 unsigned flags)
{
	enum efx_loopback_mode loopback_mode = efx->loopback_mode;
	int phy_mode = efx->phy_mode;
	int rc_test = 0, rc_reset, rc;

	efx_selftest_async_cancel(efx);

	/* Online (i.e. non-disruptive) testing
	 * This checks interrupt generation, event delivery and PHY presence. */

	rc = efx_test_phy_alive(efx, tests);
	if (rc && !rc_test)
		rc_test = rc;

	rc = efx_test_nvram(efx, tests);
	if (rc && !rc_test)
		rc_test = rc;

	rc = efx_test_interrupts(efx, tests);
	if (rc && !rc_test)
		rc_test = rc;

	rc = efx_test_eventq_irq(efx, tests);
	if (rc && !rc_test)
		rc_test = rc;

	if (rc_test)
		return rc_test;

	if (!(flags & ETH_TEST_FL_OFFLINE))
		return efx_test_phy(efx, tests, flags);

	/* Offline (i.e. disruptive) testing
	 * This checks MAC and PHY loopback on the specified port. */

	/* Detach the device so the kernel doesn't transmit during the
	 * loopback test and the watchdog timeout doesn't fire.
	 */
	efx_device_detach_sync(efx);

	if (efx->type->test_chip) {
		rc_reset = efx->type->test_chip(efx, tests);
		if (rc_reset) {
			netif_err(efx, hw, efx->net_dev,
				  "Unable to recover from chip test\n");
			efx_schedule_reset(efx, RESET_TYPE_DISABLE);
			return rc_reset;
		}

		if ((tests->memory < 0 || tests->registers < 0) && !rc_test)
			rc_test = -EIO;
	}

	/* Ensure that the phy is powered and out of loopback
	 * for the bist and loopback tests */
	mutex_lock(&efx->mac_lock);
	efx->phy_mode &= ~PHY_MODE_LOW_POWER;
	efx->loopback_mode = LOOPBACK_NONE;
	__efx_reconfigure_port(efx);
	mutex_unlock(&efx->mac_lock);

	rc = efx_test_phy(efx, tests, flags);
	if (rc && !rc_test)
		rc_test = rc;

	rc = efx_test_loopbacks(efx, tests, efx->loopback_modes);
	if (rc && !rc_test)
		rc_test = rc;

	/* restore the PHY to the previous state */
	mutex_lock(&efx->mac_lock);
	efx->phy_mode = phy_mode;
	efx->loopback_mode = loopback_mode;
	__efx_reconfigure_port(efx);
	mutex_unlock(&efx->mac_lock);

	netif_device_attach(efx->net_dev);

	return rc_test;
}

void efx_selftest_async_start(struct efx_nic *efx)
{
	struct efx_channel *channel;

	efx_for_each_channel(channel, efx)
		efx_nic_event_test_start(channel);
	schedule_delayed_work(&efx->selftest_work, IRQ_TIMEOUT);
}

void efx_selftest_async_cancel(struct efx_nic *efx)
{
	cancel_delayed_work_sync(&efx->selftest_work);
}

void efx_selftest_async_work(struct work_struct *data)
{
	struct efx_nic *efx = container_of(data, struct efx_nic,
					   selftest_work.work);
	struct efx_channel *channel;
	int cpu;

	efx_for_each_channel(channel, efx) {
		cpu = efx_nic_event_test_irq_cpu(channel);
		if (cpu < 0)
			netif_err(efx, ifup, efx->net_dev,
				  "channel %d failed to trigger an interrupt\n",
				  channel->channel);
		else
			netif_dbg(efx, ifup, efx->net_dev,
				  "channel %d triggered interrupt on CPU %d\n",
				  channel->channel, cpu);
	}
}