1/*******************************************************************************
2
3  Intel 10 Gigabit PCI Express Linux driver
4  Copyright(c) 1999 - 2012 Intel Corporation.
5
6  This program is free software; you can redistribute it and/or modify it
7  under the terms and conditions of the GNU General Public License,
8  version 2, as published by the Free Software Foundation.
9
10  This program is distributed in the hope it will be useful, but WITHOUT
11  ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
12  FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
13  more details.
14
15  You should have received a copy of the GNU General Public License along with
16  this program; if not, write to the Free Software Foundation, Inc.,
17  51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
18
19  The full GNU General Public License is included in this distribution in
20  the file called "COPYING".
21
22  Contact Information:
23  e1000-devel Mailing List <e1000-devel@lists.sourceforge.net>
24  Intel Corporation, 5200 N.E. Elam Young Parkway, Hillsboro, OR 97124-6497
25
26*******************************************************************************/
27
28#include "ixgbe.h"
29#include "ixgbe_sriov.h"
30
31/**
32 * ixgbe_cache_ring_rss - Descriptor ring to register mapping for RSS
33 * @adapter: board private structure to initialize
34 *
35 * Cache the descriptor ring offsets for RSS to the assigned rings.
36 *
37 **/
38static inline bool ixgbe_cache_ring_rss(struct ixgbe_adapter *adapter)
39{
40	int i;
41
42	if (!(adapter->flags & IXGBE_FLAG_RSS_ENABLED))
43		return false;
44
45	for (i = 0; i < adapter->num_rx_queues; i++)
46		adapter->rx_ring[i]->reg_idx = i;
47	for (i = 0; i < adapter->num_tx_queues; i++)
48		adapter->tx_ring[i]->reg_idx = i;
49
50	return true;
51}
52#ifdef CONFIG_IXGBE_DCB
53
54/* ixgbe_get_first_reg_idx - Return first register index associated with ring */
55static void ixgbe_get_first_reg_idx(struct ixgbe_adapter *adapter, u8 tc,
56				    unsigned int *tx, unsigned int *rx)
57{
58	struct net_device *dev = adapter->netdev;
59	struct ixgbe_hw *hw = &adapter->hw;
60	u8 num_tcs = netdev_get_num_tc(dev);
61
62	*tx = 0;
63	*rx = 0;
64
65	switch (hw->mac.type) {
66	case ixgbe_mac_82598EB:
67		*tx = tc << 2;
68		*rx = tc << 3;
69		break;
70	case ixgbe_mac_82599EB:
71	case ixgbe_mac_X540:
72		if (num_tcs > 4) {
73			if (tc < 3) {
74				*tx = tc << 5;
75				*rx = tc << 4;
76			} else if (tc <  5) {
77				*tx = ((tc + 2) << 4);
78				*rx = tc << 4;
79			} else if (tc < num_tcs) {
80				*tx = ((tc + 8) << 3);
81				*rx = tc << 4;
82			}
83		} else {
84			*rx =  tc << 5;
85			switch (tc) {
86			case 0:
87				*tx =  0;
88				break;
89			case 1:
90				*tx = 64;
91				break;
92			case 2:
93				*tx = 96;
94				break;
95			case 3:
96				*tx = 112;
97				break;
98			default:
99				break;
100			}
101		}
102		break;
103	default:
104		break;
105	}
106}
107
108/**
109 * ixgbe_cache_ring_dcb - Descriptor ring to register mapping for DCB
110 * @adapter: board private structure to initialize
111 *
112 * Cache the descriptor ring offsets for DCB to the assigned rings.
113 *
114 **/
115static inline bool ixgbe_cache_ring_dcb(struct ixgbe_adapter *adapter)
116{
117	struct net_device *dev = adapter->netdev;
118	int i, j, k;
119	u8 num_tcs = netdev_get_num_tc(dev);
120
121	if (!num_tcs)
122		return false;
123
124	for (i = 0, k = 0; i < num_tcs; i++) {
125		unsigned int tx_s, rx_s;
126		u16 count = dev->tc_to_txq[i].count;
127
128		ixgbe_get_first_reg_idx(adapter, i, &tx_s, &rx_s);
129		for (j = 0; j < count; j++, k++) {
130			adapter->tx_ring[k]->reg_idx = tx_s + j;
131			adapter->rx_ring[k]->reg_idx = rx_s + j;
132			adapter->tx_ring[k]->dcb_tc = i;
133			adapter->rx_ring[k]->dcb_tc = i;
134		}
135	}
136
137	return true;
138}
139#endif
140
141/**
142 * ixgbe_cache_ring_fdir - Descriptor ring to register mapping for Flow Director
143 * @adapter: board private structure to initialize
144 *
145 * Cache the descriptor ring offsets for Flow Director to the assigned rings.
146 *
147 **/
148static inline bool ixgbe_cache_ring_fdir(struct ixgbe_adapter *adapter)
149{
150	int i;
151	bool ret = false;
152
153	if ((adapter->flags & IXGBE_FLAG_RSS_ENABLED) &&
154	    (adapter->flags & IXGBE_FLAG_FDIR_HASH_CAPABLE)) {
155		for (i = 0; i < adapter->num_rx_queues; i++)
156			adapter->rx_ring[i]->reg_idx = i;
157		for (i = 0; i < adapter->num_tx_queues; i++)
158			adapter->tx_ring[i]->reg_idx = i;
159		ret = true;
160	}
161
162	return ret;
163}
164
165#ifdef IXGBE_FCOE
166/**
167 * ixgbe_cache_ring_fcoe - Descriptor ring to register mapping for the FCoE
168 * @adapter: board private structure to initialize
169 *
170 * Cache the descriptor ring offsets for FCoE mode to the assigned rings.
171 *
172 */
173static inline bool ixgbe_cache_ring_fcoe(struct ixgbe_adapter *adapter)
174{
175	struct ixgbe_ring_feature *f = &adapter->ring_feature[RING_F_FCOE];
176	int i;
177	u8 fcoe_rx_i = 0, fcoe_tx_i = 0;
178
179	if (!(adapter->flags & IXGBE_FLAG_FCOE_ENABLED))
180		return false;
181
182	if (adapter->flags & IXGBE_FLAG_RSS_ENABLED) {
183		if (adapter->flags & IXGBE_FLAG_FDIR_HASH_CAPABLE)
184			ixgbe_cache_ring_fdir(adapter);
185		else
186			ixgbe_cache_ring_rss(adapter);
187
188		fcoe_rx_i = f->mask;
189		fcoe_tx_i = f->mask;
190	}
191	for (i = 0; i < f->indices; i++, fcoe_rx_i++, fcoe_tx_i++) {
192		adapter->rx_ring[f->mask + i]->reg_idx = fcoe_rx_i;
193		adapter->tx_ring[f->mask + i]->reg_idx = fcoe_tx_i;
194	}
195	return true;
196}
197
198#endif /* IXGBE_FCOE */
199/**
200 * ixgbe_cache_ring_sriov - Descriptor ring to register mapping for sriov
201 * @adapter: board private structure to initialize
202 *
203 * SR-IOV doesn't use any descriptor rings but changes the default if
204 * no other mapping is used.
205 *
206 */
207static inline bool ixgbe_cache_ring_sriov(struct ixgbe_adapter *adapter)
208{
209	adapter->rx_ring[0]->reg_idx = adapter->num_vfs * 2;
210	adapter->tx_ring[0]->reg_idx = adapter->num_vfs * 2;
211	if (adapter->num_vfs)
212		return true;
213	else
214		return false;
215}
216
217/**
218 * ixgbe_cache_ring_register - Descriptor ring to register mapping
219 * @adapter: board private structure to initialize
220 *
221 * Once we know the feature-set enabled for the device, we'll cache
222 * the register offset the descriptor ring is assigned to.
223 *
224 * Note, the order the various feature calls is important.  It must start with
225 * the "most" features enabled at the same time, then trickle down to the
226 * least amount of features turned on at once.
227 **/
228static void ixgbe_cache_ring_register(struct ixgbe_adapter *adapter)
229{
230	/* start with default case */
231	adapter->rx_ring[0]->reg_idx = 0;
232	adapter->tx_ring[0]->reg_idx = 0;
233
234	if (ixgbe_cache_ring_sriov(adapter))
235		return;
236
237#ifdef CONFIG_IXGBE_DCB
238	if (ixgbe_cache_ring_dcb(adapter))
239		return;
240#endif
241
242#ifdef IXGBE_FCOE
243	if (ixgbe_cache_ring_fcoe(adapter))
244		return;
245#endif /* IXGBE_FCOE */
246
247	if (ixgbe_cache_ring_fdir(adapter))
248		return;
249
250	if (ixgbe_cache_ring_rss(adapter))
251		return;
252}
253
254/**
255 * ixgbe_set_sriov_queues: Allocate queues for IOV use
256 * @adapter: board private structure to initialize
257 *
258 * IOV doesn't actually use anything, so just NAK the
259 * request for now and let the other queue routines
260 * figure out what to do.
261 */
262static inline bool ixgbe_set_sriov_queues(struct ixgbe_adapter *adapter)
263{
264	return false;
265}
266
267/**
268 * ixgbe_set_rss_queues: Allocate queues for RSS
269 * @adapter: board private structure to initialize
270 *
271 * This is our "base" multiqueue mode.  RSS (Receive Side Scaling) will try
272 * to allocate one Rx queue per CPU, and if available, one Tx queue per CPU.
273 *
274 **/
275static inline bool ixgbe_set_rss_queues(struct ixgbe_adapter *adapter)
276{
277	bool ret = false;
278	struct ixgbe_ring_feature *f = &adapter->ring_feature[RING_F_RSS];
279
280	if (adapter->flags & IXGBE_FLAG_RSS_ENABLED) {
281		f->mask = 0xF;
282		adapter->num_rx_queues = f->indices;
283		adapter->num_tx_queues = f->indices;
284		ret = true;
285	}
286
287	return ret;
288}
289
290/**
291 * ixgbe_set_fdir_queues: Allocate queues for Flow Director
292 * @adapter: board private structure to initialize
293 *
294 * Flow Director is an advanced Rx filter, attempting to get Rx flows back
295 * to the original CPU that initiated the Tx session.  This runs in addition
296 * to RSS, so if a packet doesn't match an FDIR filter, we can still spread the
297 * Rx load across CPUs using RSS.
298 *
299 **/
300static inline bool ixgbe_set_fdir_queues(struct ixgbe_adapter *adapter)
301{
302	bool ret = false;
303	struct ixgbe_ring_feature *f_fdir = &adapter->ring_feature[RING_F_FDIR];
304
305	f_fdir->indices = min_t(int, num_online_cpus(), f_fdir->indices);
306	f_fdir->mask = 0;
307
308	/*
309	 * Use RSS in addition to Flow Director to ensure the best
310	 * distribution of flows across cores, even when an FDIR flow
311	 * isn't matched.
312	 */
313	if ((adapter->flags & IXGBE_FLAG_RSS_ENABLED) &&
314	    (adapter->flags & IXGBE_FLAG_FDIR_HASH_CAPABLE)) {
315		adapter->num_tx_queues = f_fdir->indices;
316		adapter->num_rx_queues = f_fdir->indices;
317		ret = true;
318	} else {
319		adapter->flags &= ~IXGBE_FLAG_FDIR_HASH_CAPABLE;
320	}
321	return ret;
322}
323
324#ifdef IXGBE_FCOE
325/**
326 * ixgbe_set_fcoe_queues: Allocate queues for Fiber Channel over Ethernet (FCoE)
327 * @adapter: board private structure to initialize
328 *
329 * FCoE RX FCRETA can use up to 8 rx queues for up to 8 different exchanges.
330 * The ring feature mask is not used as a mask for FCoE, as it can take any 8
331 * rx queues out of the max number of rx queues, instead, it is used as the
332 * index of the first rx queue used by FCoE.
333 *
334 **/
335static inline bool ixgbe_set_fcoe_queues(struct ixgbe_adapter *adapter)
336{
337	struct ixgbe_ring_feature *f = &adapter->ring_feature[RING_F_FCOE];
338
339	if (!(adapter->flags & IXGBE_FLAG_FCOE_ENABLED))
340		return false;
341
342	f->indices = min_t(int, num_online_cpus(), f->indices);
343
344	adapter->num_rx_queues = 1;
345	adapter->num_tx_queues = 1;
346
347	if (adapter->flags & IXGBE_FLAG_RSS_ENABLED) {
348		e_info(probe, "FCoE enabled with RSS\n");
349		if (adapter->flags & IXGBE_FLAG_FDIR_HASH_CAPABLE)
350			ixgbe_set_fdir_queues(adapter);
351		else
352			ixgbe_set_rss_queues(adapter);
353	}
354
355	/* adding FCoE rx rings to the end */
356	f->mask = adapter->num_rx_queues;
357	adapter->num_rx_queues += f->indices;
358	adapter->num_tx_queues += f->indices;
359
360	return true;
361}
362#endif /* IXGBE_FCOE */
363
364/* Artificial max queue cap per traffic class in DCB mode */
365#define DCB_QUEUE_CAP 8
366
367#ifdef CONFIG_IXGBE_DCB
368static inline bool ixgbe_set_dcb_queues(struct ixgbe_adapter *adapter)
369{
370	int per_tc_q, q, i, offset = 0;
371	struct net_device *dev = adapter->netdev;
372	int tcs = netdev_get_num_tc(dev);
373
374	if (!tcs)
375		return false;
376
377	/* Map queue offset and counts onto allocated tx queues */
378	per_tc_q = min_t(unsigned int, dev->num_tx_queues / tcs, DCB_QUEUE_CAP);
379	q = min_t(int, num_online_cpus(), per_tc_q);
380
381	for (i = 0; i < tcs; i++) {
382		netdev_set_tc_queue(dev, i, q, offset);
383		offset += q;
384	}
385
386	adapter->num_tx_queues = q * tcs;
387	adapter->num_rx_queues = q * tcs;
388
389#ifdef IXGBE_FCOE
390	/* FCoE enabled queues require special configuration indexed
391	 * by feature specific indices and mask. Here we map FCoE
392	 * indices onto the DCB queue pairs allowing FCoE to own
393	 * configuration later.
394	 */
395	if (adapter->flags & IXGBE_FLAG_FCOE_ENABLED) {
396		u8 prio_tc[MAX_USER_PRIORITY] = {0};
397		int tc;
398		struct ixgbe_ring_feature *f =
399					&adapter->ring_feature[RING_F_FCOE];
400
401		ixgbe_dcb_unpack_map(&adapter->dcb_cfg, DCB_TX_CONFIG, prio_tc);
402		tc = prio_tc[adapter->fcoe.up];
403		f->indices = dev->tc_to_txq[tc].count;
404		f->mask = dev->tc_to_txq[tc].offset;
405	}
406#endif
407
408	return true;
409}
410#endif
411
412/**
413 * ixgbe_set_num_queues: Allocate queues for device, feature dependent
414 * @adapter: board private structure to initialize
415 *
416 * This is the top level queue allocation routine.  The order here is very
417 * important, starting with the "most" number of features turned on at once,
418 * and ending with the smallest set of features.  This way large combinations
419 * can be allocated if they're turned on, and smaller combinations are the
420 * fallthrough conditions.
421 *
422 **/
423static int ixgbe_set_num_queues(struct ixgbe_adapter *adapter)
424{
425	/* Start with base case */
426	adapter->num_rx_queues = 1;
427	adapter->num_tx_queues = 1;
428	adapter->num_rx_pools = adapter->num_rx_queues;
429	adapter->num_rx_queues_per_pool = 1;
430
431	if (ixgbe_set_sriov_queues(adapter))
432		goto done;
433
434#ifdef CONFIG_IXGBE_DCB
435	if (ixgbe_set_dcb_queues(adapter))
436		goto done;
437
438#endif
439#ifdef IXGBE_FCOE
440	if (ixgbe_set_fcoe_queues(adapter))
441		goto done;
442
443#endif /* IXGBE_FCOE */
444	if (ixgbe_set_fdir_queues(adapter))
445		goto done;
446
447	if (ixgbe_set_rss_queues(adapter))
448		goto done;
449
450	/* fallback to base case */
451	adapter->num_rx_queues = 1;
452	adapter->num_tx_queues = 1;
453
454done:
455	if ((adapter->netdev->reg_state == NETREG_UNREGISTERED) ||
456	    (adapter->netdev->reg_state == NETREG_UNREGISTERING))
457		return 0;
458
459	/* Notify the stack of the (possibly) reduced queue counts. */
460	netif_set_real_num_tx_queues(adapter->netdev, adapter->num_tx_queues);
461	return netif_set_real_num_rx_queues(adapter->netdev,
462					    adapter->num_rx_queues);
463}
464
465static void ixgbe_acquire_msix_vectors(struct ixgbe_adapter *adapter,
466				       int vectors)
467{
468	int err, vector_threshold;
469
470	/* We'll want at least 2 (vector_threshold):
471	 * 1) TxQ[0] + RxQ[0] handler
472	 * 2) Other (Link Status Change, etc.)
473	 */
474	vector_threshold = MIN_MSIX_COUNT;
475
476	/*
477	 * The more we get, the more we will assign to Tx/Rx Cleanup
478	 * for the separate queues...where Rx Cleanup >= Tx Cleanup.
479	 * Right now, we simply care about how many we'll get; we'll
480	 * set them up later while requesting irq's.
481	 */
482	while (vectors >= vector_threshold) {
483		err = pci_enable_msix(adapter->pdev, adapter->msix_entries,
484				      vectors);
485		if (!err) /* Success in acquiring all requested vectors. */
486			break;
487		else if (err < 0)
488			vectors = 0; /* Nasty failure, quit now */
489		else /* err == number of vectors we should try again with */
490			vectors = err;
491	}
492
493	if (vectors < vector_threshold) {
494		/* Can't allocate enough MSI-X interrupts?  Oh well.
495		 * This just means we'll go with either a single MSI
496		 * vector or fall back to legacy interrupts.
497		 */
498		netif_printk(adapter, hw, KERN_DEBUG, adapter->netdev,
499			     "Unable to allocate MSI-X interrupts\n");
500		adapter->flags &= ~IXGBE_FLAG_MSIX_ENABLED;
501		kfree(adapter->msix_entries);
502		adapter->msix_entries = NULL;
503	} else {
504		adapter->flags |= IXGBE_FLAG_MSIX_ENABLED; /* Woot! */
505		/*
506		 * Adjust for only the vectors we'll use, which is minimum
507		 * of max_msix_q_vectors + NON_Q_VECTORS, or the number of
508		 * vectors we were allocated.
509		 */
510		adapter->num_msix_vectors = min(vectors,
511				   adapter->max_msix_q_vectors + NON_Q_VECTORS);
512	}
513}
514
515static void ixgbe_add_ring(struct ixgbe_ring *ring,
516			   struct ixgbe_ring_container *head)
517{
518	ring->next = head->ring;
519	head->ring = ring;
520	head->count++;
521}
522
523/**
524 * ixgbe_alloc_q_vector - Allocate memory for a single interrupt vector
525 * @adapter: board private structure to initialize
526 * @v_idx: index of vector in adapter struct
527 *
528 * We allocate one q_vector.  If allocation fails we return -ENOMEM.
529 **/
530static int ixgbe_alloc_q_vector(struct ixgbe_adapter *adapter, int v_idx,
531				int txr_count, int txr_idx,
532				int rxr_count, int rxr_idx)
533{
534	struct ixgbe_q_vector *q_vector;
535	struct ixgbe_ring *ring;
536	int node = -1;
537	int cpu = -1;
538	int ring_count, size;
539
540	ring_count = txr_count + rxr_count;
541	size = sizeof(struct ixgbe_q_vector) +
542	       (sizeof(struct ixgbe_ring) * ring_count);
543
544	/* customize cpu for Flow Director mapping */
545	if (adapter->flags & IXGBE_FLAG_FDIR_HASH_CAPABLE) {
546		if (cpu_online(v_idx)) {
547			cpu = v_idx;
548			node = cpu_to_node(cpu);
549		}
550	}
551
552	/* allocate q_vector and rings */
553	q_vector = kzalloc_node(size, GFP_KERNEL, node);
554	if (!q_vector)
555		q_vector = kzalloc(size, GFP_KERNEL);
556	if (!q_vector)
557		return -ENOMEM;
558
559	/* setup affinity mask and node */
560	if (cpu != -1)
561		cpumask_set_cpu(cpu, &q_vector->affinity_mask);
562	else
563		cpumask_copy(&q_vector->affinity_mask, cpu_online_mask);
564	q_vector->numa_node = node;
565
566	/* initialize NAPI */
567	netif_napi_add(adapter->netdev, &q_vector->napi,
568		       ixgbe_poll, 64);
569
570	/* tie q_vector and adapter together */
571	adapter->q_vector[v_idx] = q_vector;
572	q_vector->adapter = adapter;
573	q_vector->v_idx = v_idx;
574
575	/* initialize work limits */
576	q_vector->tx.work_limit = adapter->tx_work_limit;
577
578	/* initialize pointer to rings */
579	ring = q_vector->ring;
580
581	while (txr_count) {
582		/* assign generic ring traits */
583		ring->dev = &adapter->pdev->dev;
584		ring->netdev = adapter->netdev;
585
586		/* configure backlink on ring */
587		ring->q_vector = q_vector;
588
589		/* update q_vector Tx values */
590		ixgbe_add_ring(ring, &q_vector->tx);
591
592		/* apply Tx specific ring traits */
593		ring->count = adapter->tx_ring_count;
594		ring->queue_index = txr_idx;
595
596		/* assign ring to adapter */
597		adapter->tx_ring[txr_idx] = ring;
598
599		/* update count and index */
600		txr_count--;
601		txr_idx++;
602
603		/* push pointer to next ring */
604		ring++;
605	}
606
607	while (rxr_count) {
608		/* assign generic ring traits */
609		ring->dev = &adapter->pdev->dev;
610		ring->netdev = adapter->netdev;
611
612		/* configure backlink on ring */
613		ring->q_vector = q_vector;
614
615		/* update q_vector Rx values */
616		ixgbe_add_ring(ring, &q_vector->rx);
617
618		/*
619		 * 82599 errata, UDP frames with a 0 checksum
620		 * can be marked as checksum errors.
621		 */
622		if (adapter->hw.mac.type == ixgbe_mac_82599EB)
623			set_bit(__IXGBE_RX_CSUM_UDP_ZERO_ERR, &ring->state);
624
625#ifdef IXGBE_FCOE
626		if (adapter->netdev->features & NETIF_F_FCOE_MTU) {
627			struct ixgbe_ring_feature *f;
628			f = &adapter->ring_feature[RING_F_FCOE];
629			if ((rxr_idx >= f->mask) &&
630			    (rxr_idx < f->mask + f->indices))
631				set_bit(__IXGBE_RX_FCOE, &ring->state);
632		}
633
634#endif /* IXGBE_FCOE */
635		/* apply Rx specific ring traits */
636		ring->count = adapter->rx_ring_count;
637		ring->queue_index = rxr_idx;
638
639		/* assign ring to adapter */
640		adapter->rx_ring[rxr_idx] = ring;
641
642		/* update count and index */
643		rxr_count--;
644		rxr_idx++;
645
646		/* push pointer to next ring */
647		ring++;
648	}
649
650	return 0;
651}
652
653/**
654 * ixgbe_free_q_vector - Free memory allocated for specific interrupt vector
655 * @adapter: board private structure to initialize
656 * @v_idx: Index of vector to be freed
657 *
658 * This function frees the memory allocated to the q_vector.  In addition if
659 * NAPI is enabled it will delete any references to the NAPI struct prior
660 * to freeing the q_vector.
661 **/
662static void ixgbe_free_q_vector(struct ixgbe_adapter *adapter, int v_idx)
663{
664	struct ixgbe_q_vector *q_vector = adapter->q_vector[v_idx];
665	struct ixgbe_ring *ring;
666
667	ixgbe_for_each_ring(ring, q_vector->tx)
668		adapter->tx_ring[ring->queue_index] = NULL;
669
670	ixgbe_for_each_ring(ring, q_vector->rx)
671		adapter->rx_ring[ring->queue_index] = NULL;
672
673	adapter->q_vector[v_idx] = NULL;
674	netif_napi_del(&q_vector->napi);
675
676	/*
677	 * ixgbe_get_stats64() might access the rings on this vector,
678	 * we must wait a grace period before freeing it.
679	 */
680	kfree_rcu(q_vector, rcu);
681}
682
683/**
684 * ixgbe_alloc_q_vectors - Allocate memory for interrupt vectors
685 * @adapter: board private structure to initialize
686 *
687 * We allocate one q_vector per queue interrupt.  If allocation fails we
688 * return -ENOMEM.
689 **/
690static int ixgbe_alloc_q_vectors(struct ixgbe_adapter *adapter)
691{
692	int q_vectors = adapter->num_msix_vectors - NON_Q_VECTORS;
693	int rxr_remaining = adapter->num_rx_queues;
694	int txr_remaining = adapter->num_tx_queues;
695	int rxr_idx = 0, txr_idx = 0, v_idx = 0;
696	int err;
697
698	/* only one q_vector if MSI-X is disabled. */
699	if (!(adapter->flags & IXGBE_FLAG_MSIX_ENABLED))
700		q_vectors = 1;
701
702	if (q_vectors >= (rxr_remaining + txr_remaining)) {
703		for (; rxr_remaining; v_idx++, q_vectors--) {
704			int rqpv = DIV_ROUND_UP(rxr_remaining, q_vectors);
705			err = ixgbe_alloc_q_vector(adapter, v_idx,
706						   0, 0, rqpv, rxr_idx);
707
708			if (err)
709				goto err_out;
710
711			/* update counts and index */
712			rxr_remaining -= rqpv;
713			rxr_idx += rqpv;
714		}
715	}
716
717	for (; q_vectors; v_idx++, q_vectors--) {
718		int rqpv = DIV_ROUND_UP(rxr_remaining, q_vectors);
719		int tqpv = DIV_ROUND_UP(txr_remaining, q_vectors);
720		err = ixgbe_alloc_q_vector(adapter, v_idx,
721					   tqpv, txr_idx,
722					   rqpv, rxr_idx);
723
724		if (err)
725			goto err_out;
726
727		/* update counts and index */
728		rxr_remaining -= rqpv;
729		rxr_idx += rqpv;
730		txr_remaining -= tqpv;
731		txr_idx += tqpv;
732	}
733
734	return 0;
735
736err_out:
737	while (v_idx) {
738		v_idx--;
739		ixgbe_free_q_vector(adapter, v_idx);
740	}
741
742	return -ENOMEM;
743}
744
745/**
746 * ixgbe_free_q_vectors - Free memory allocated for interrupt vectors
747 * @adapter: board private structure to initialize
748 *
749 * This function frees the memory allocated to the q_vectors.  In addition if
750 * NAPI is enabled it will delete any references to the NAPI struct prior
751 * to freeing the q_vector.
752 **/
753static void ixgbe_free_q_vectors(struct ixgbe_adapter *adapter)
754{
755	int v_idx, q_vectors;
756
757	if (adapter->flags & IXGBE_FLAG_MSIX_ENABLED)
758		q_vectors = adapter->num_msix_vectors - NON_Q_VECTORS;
759	else
760		q_vectors = 1;
761
762	for (v_idx = 0; v_idx < q_vectors; v_idx++)
763		ixgbe_free_q_vector(adapter, v_idx);
764}
765
766static void ixgbe_reset_interrupt_capability(struct ixgbe_adapter *adapter)
767{
768	if (adapter->flags & IXGBE_FLAG_MSIX_ENABLED) {
769		adapter->flags &= ~IXGBE_FLAG_MSIX_ENABLED;
770		pci_disable_msix(adapter->pdev);
771		kfree(adapter->msix_entries);
772		adapter->msix_entries = NULL;
773	} else if (adapter->flags & IXGBE_FLAG_MSI_ENABLED) {
774		adapter->flags &= ~IXGBE_FLAG_MSI_ENABLED;
775		pci_disable_msi(adapter->pdev);
776	}
777}
778
779/**
780 * ixgbe_set_interrupt_capability - set MSI-X or MSI if supported
781 * @adapter: board private structure to initialize
782 *
783 * Attempt to configure the interrupts using the best available
784 * capabilities of the hardware and the kernel.
785 **/
786static int ixgbe_set_interrupt_capability(struct ixgbe_adapter *adapter)
787{
788	struct ixgbe_hw *hw = &adapter->hw;
789	int err = 0;
790	int vector, v_budget;
791
792	/*
793	 * It's easy to be greedy for MSI-X vectors, but it really
794	 * doesn't do us much good if we have a lot more vectors
795	 * than CPU's.  So let's be conservative and only ask for
796	 * (roughly) the same number of vectors as there are CPU's.
797	 * The default is to use pairs of vectors.
798	 */
799	v_budget = max(adapter->num_rx_queues, adapter->num_tx_queues);
800	v_budget = min_t(int, v_budget, num_online_cpus());
801	v_budget += NON_Q_VECTORS;
802
803	/*
804	 * At the same time, hardware can only support a maximum of
805	 * hw.mac->max_msix_vectors vectors.  With features
806	 * such as RSS and VMDq, we can easily surpass the number of Rx and Tx
807	 * descriptor queues supported by our device.  Thus, we cap it off in
808	 * those rare cases where the cpu count also exceeds our vector limit.
809	 */
810	v_budget = min_t(int, v_budget, hw->mac.max_msix_vectors);
811
812	/* A failure in MSI-X entry allocation isn't fatal, but it does
813	 * mean we disable MSI-X capabilities of the adapter. */
814	adapter->msix_entries = kcalloc(v_budget,
815					sizeof(struct msix_entry), GFP_KERNEL);
816	if (adapter->msix_entries) {
817		for (vector = 0; vector < v_budget; vector++)
818			adapter->msix_entries[vector].entry = vector;
819
820		ixgbe_acquire_msix_vectors(adapter, v_budget);
821
822		if (adapter->flags & IXGBE_FLAG_MSIX_ENABLED)
823			goto out;
824	}
825
826	adapter->flags &= ~IXGBE_FLAG_DCB_ENABLED;
827	adapter->flags &= ~IXGBE_FLAG_RSS_ENABLED;
828	if (adapter->flags & IXGBE_FLAG_FDIR_HASH_CAPABLE) {
829		e_err(probe,
830		      "ATR is not supported while multiple "
831		      "queues are disabled.  Disabling Flow Director\n");
832	}
833	adapter->flags &= ~IXGBE_FLAG_FDIR_HASH_CAPABLE;
834	adapter->atr_sample_rate = 0;
835	if (adapter->flags & IXGBE_FLAG_SRIOV_ENABLED)
836		ixgbe_disable_sriov(adapter);
837
838	err = ixgbe_set_num_queues(adapter);
839	if (err)
840		return err;
841
842	err = pci_enable_msi(adapter->pdev);
843	if (!err) {
844		adapter->flags |= IXGBE_FLAG_MSI_ENABLED;
845	} else {
846		netif_printk(adapter, hw, KERN_DEBUG, adapter->netdev,
847			     "Unable to allocate MSI interrupt, "
848			     "falling back to legacy.  Error: %d\n", err);
849		/* reset err */
850		err = 0;
851	}
852
853out:
854	return err;
855}
856
857/**
858 * ixgbe_init_interrupt_scheme - Determine proper interrupt scheme
859 * @adapter: board private structure to initialize
860 *
861 * We determine which interrupt scheme to use based on...
862 * - Kernel support (MSI, MSI-X)
863 *   - which can be user-defined (via MODULE_PARAM)
864 * - Hardware queue count (num_*_queues)
865 *   - defined by miscellaneous hardware support/features (RSS, etc.)
866 **/
867int ixgbe_init_interrupt_scheme(struct ixgbe_adapter *adapter)
868{
869	int err;
870
871	/* Number of supported queues */
872	err = ixgbe_set_num_queues(adapter);
873	if (err)
874		return err;
875
876	err = ixgbe_set_interrupt_capability(adapter);
877	if (err) {
878		e_dev_err("Unable to setup interrupt capabilities\n");
879		goto err_set_interrupt;
880	}
881
882	err = ixgbe_alloc_q_vectors(adapter);
883	if (err) {
884		e_dev_err("Unable to allocate memory for queue vectors\n");
885		goto err_alloc_q_vectors;
886	}
887
888	ixgbe_cache_ring_register(adapter);
889
890	e_dev_info("Multiqueue %s: Rx Queue count = %u, Tx Queue count = %u\n",
891		   (adapter->num_rx_queues > 1) ? "Enabled" : "Disabled",
892		   adapter->num_rx_queues, adapter->num_tx_queues);
893
894	set_bit(__IXGBE_DOWN, &adapter->state);
895
896	return 0;
897
898err_alloc_q_vectors:
899	ixgbe_reset_interrupt_capability(adapter);
900err_set_interrupt:
901	return err;
902}
903
904/**
905 * ixgbe_clear_interrupt_scheme - Clear the current interrupt scheme settings
906 * @adapter: board private structure to clear interrupt scheme on
907 *
908 * We go through and clear interrupt specific resources and reset the structure
909 * to pre-load conditions
910 **/
911void ixgbe_clear_interrupt_scheme(struct ixgbe_adapter *adapter)
912{
913	adapter->num_tx_queues = 0;
914	adapter->num_rx_queues = 0;
915
916	ixgbe_free_q_vectors(adapter);
917	ixgbe_reset_interrupt_capability(adapter);
918}
919
920void ixgbe_tx_ctxtdesc(struct ixgbe_ring *tx_ring, u32 vlan_macip_lens,
921		       u32 fcoe_sof_eof, u32 type_tucmd, u32 mss_l4len_idx)
922{
923	struct ixgbe_adv_tx_context_desc *context_desc;
924	u16 i = tx_ring->next_to_use;
925
926	context_desc = IXGBE_TX_CTXTDESC(tx_ring, i);
927
928	i++;
929	tx_ring->next_to_use = (i < tx_ring->count) ? i : 0;
930
931	/* set bits to identify this as an advanced context descriptor */
932	type_tucmd |= IXGBE_TXD_CMD_DEXT | IXGBE_ADVTXD_DTYP_CTXT;
933
934	context_desc->vlan_macip_lens	= cpu_to_le32(vlan_macip_lens);
935	context_desc->seqnum_seed	= cpu_to_le32(fcoe_sof_eof);
936	context_desc->type_tucmd_mlhl	= cpu_to_le32(type_tucmd);
937	context_desc->mss_l4len_idx	= cpu_to_le32(mss_l4len_idx);
938}
939
940