1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Huawei HiNIC PCI Express Linux driver
4  * Copyright(c) 2017 Huawei Technologies Co., Ltd
5  */
6 
7 #include <linux/kernel.h>
8 #include <linux/netdevice.h>
9 #include <linux/u64_stats_sync.h>
10 #include <linux/errno.h>
11 #include <linux/types.h>
12 #include <linux/pci.h>
13 #include <linux/device.h>
14 #include <linux/dma-mapping.h>
15 #include <linux/slab.h>
16 #include <linux/interrupt.h>
17 #include <linux/skbuff.h>
18 #include <linux/smp.h>
19 #include <asm/byteorder.h>
20 #include <linux/ip.h>
21 #include <linux/tcp.h>
22 #include <linux/sctp.h>
23 #include <linux/ipv6.h>
24 #include <net/ipv6.h>
25 #include <net/checksum.h>
26 #include <net/ip6_checksum.h>
27 
28 #include "hinic_common.h"
29 #include "hinic_hw_if.h"
30 #include "hinic_hw_wqe.h"
31 #include "hinic_hw_wq.h"
32 #include "hinic_hw_qp.h"
33 #include "hinic_hw_dev.h"
34 #include "hinic_dev.h"
35 #include "hinic_tx.h"
36 
37 #define TX_IRQ_NO_PENDING               0
38 #define TX_IRQ_NO_COALESC               0
39 #define TX_IRQ_NO_LLI_TIMER             0
40 #define TX_IRQ_NO_CREDIT                0
41 #define TX_IRQ_NO_RESEND_TIMER          0
42 
43 #define CI_UPDATE_NO_PENDING            0
44 #define CI_UPDATE_NO_COALESC            0
45 
46 #define HW_CONS_IDX(sq)                 be16_to_cpu(*(u16 *)((sq)->hw_ci_addr))
47 
48 #define MIN_SKB_LEN                     17
49 
50 #define	MAX_PAYLOAD_OFFSET	        221
51 #define TRANSPORT_OFFSET(l4_hdr, skb)	((u32)((l4_hdr) - (skb)->data))
52 
53 union hinic_l3 {
54 	struct iphdr *v4;
55 	struct ipv6hdr *v6;
56 	unsigned char *hdr;
57 };
58 
59 union hinic_l4 {
60 	struct tcphdr *tcp;
61 	struct udphdr *udp;
62 	unsigned char *hdr;
63 };
64 
65 enum hinic_offload_type {
66 	TX_OFFLOAD_TSO     = BIT(0),
67 	TX_OFFLOAD_CSUM    = BIT(1),
68 	TX_OFFLOAD_VLAN    = BIT(2),
69 	TX_OFFLOAD_INVALID = BIT(3),
70 };
71 
72 /**
73  * hinic_txq_clean_stats - Clean the statistics of specific queue
74  * @txq: Logical Tx Queue
75  **/
76 void hinic_txq_clean_stats(struct hinic_txq *txq)
77 {
78 	struct hinic_txq_stats *txq_stats = &txq->txq_stats;
79 
80 	u64_stats_update_begin(&txq_stats->syncp);
81 	txq_stats->pkts    = 0;
82 	txq_stats->bytes   = 0;
83 	txq_stats->tx_busy = 0;
84 	txq_stats->tx_wake = 0;
85 	txq_stats->tx_dropped = 0;
86 	txq_stats->big_frags_pkts = 0;
87 	u64_stats_update_end(&txq_stats->syncp);
88 }
89 
90 /**
91  * hinic_txq_get_stats - get statistics of Tx Queue
92  * @txq: Logical Tx Queue
93  * @stats: return updated stats here
94  **/
95 void hinic_txq_get_stats(struct hinic_txq *txq, struct hinic_txq_stats *stats)
96 {
97 	struct hinic_txq_stats *txq_stats = &txq->txq_stats;
98 	unsigned int start;
99 
100 	u64_stats_update_begin(&stats->syncp);
101 	do {
102 		start = u64_stats_fetch_begin(&txq_stats->syncp);
103 		stats->pkts    = txq_stats->pkts;
104 		stats->bytes   = txq_stats->bytes;
105 		stats->tx_busy = txq_stats->tx_busy;
106 		stats->tx_wake = txq_stats->tx_wake;
107 		stats->tx_dropped = txq_stats->tx_dropped;
108 		stats->big_frags_pkts = txq_stats->big_frags_pkts;
109 	} while (u64_stats_fetch_retry(&txq_stats->syncp, start));
110 	u64_stats_update_end(&stats->syncp);
111 }
112 
113 /**
114  * txq_stats_init - Initialize the statistics of specific queue
115  * @txq: Logical Tx Queue
116  **/
117 static void txq_stats_init(struct hinic_txq *txq)
118 {
119 	struct hinic_txq_stats *txq_stats = &txq->txq_stats;
120 
121 	u64_stats_init(&txq_stats->syncp);
122 	hinic_txq_clean_stats(txq);
123 }
124 
125 /**
126  * tx_map_skb - dma mapping for skb and return sges
127  * @nic_dev: nic device
128  * @skb: the skb
129  * @sges: returned sges
130  *
131  * Return 0 - Success, negative - Failure
132  **/
133 static int tx_map_skb(struct hinic_dev *nic_dev, struct sk_buff *skb,
134 		      struct hinic_sge *sges)
135 {
136 	struct hinic_hwdev *hwdev = nic_dev->hwdev;
137 	struct hinic_hwif *hwif = hwdev->hwif;
138 	struct pci_dev *pdev = hwif->pdev;
139 	struct skb_frag_struct *frag;
140 	dma_addr_t dma_addr;
141 	int i, j;
142 
143 	dma_addr = dma_map_single(&pdev->dev, skb->data, skb_headlen(skb),
144 				  DMA_TO_DEVICE);
145 	if (dma_mapping_error(&pdev->dev, dma_addr)) {
146 		dev_err(&pdev->dev, "Failed to map Tx skb data\n");
147 		return -EFAULT;
148 	}
149 
150 	hinic_set_sge(&sges[0], dma_addr, skb_headlen(skb));
151 
152 	for (i = 0 ; i < skb_shinfo(skb)->nr_frags; i++) {
153 		frag = &skb_shinfo(skb)->frags[i];
154 
155 		dma_addr = skb_frag_dma_map(&pdev->dev, frag, 0,
156 					    skb_frag_size(frag),
157 					    DMA_TO_DEVICE);
158 		if (dma_mapping_error(&pdev->dev, dma_addr)) {
159 			dev_err(&pdev->dev, "Failed to map Tx skb frag\n");
160 			goto err_tx_map;
161 		}
162 
163 		hinic_set_sge(&sges[i + 1], dma_addr, skb_frag_size(frag));
164 	}
165 
166 	return 0;
167 
168 err_tx_map:
169 	for (j = 0; j < i; j++)
170 		dma_unmap_page(&pdev->dev, hinic_sge_to_dma(&sges[j + 1]),
171 			       sges[j + 1].len, DMA_TO_DEVICE);
172 
173 	dma_unmap_single(&pdev->dev, hinic_sge_to_dma(&sges[0]), sges[0].len,
174 			 DMA_TO_DEVICE);
175 	return -EFAULT;
176 }
177 
178 /**
179  * tx_unmap_skb - unmap the dma address of the skb
180  * @nic_dev: nic device
181  * @skb: the skb
182  * @sges: the sges that are connected to the skb
183  **/
184 static void tx_unmap_skb(struct hinic_dev *nic_dev, struct sk_buff *skb,
185 			 struct hinic_sge *sges)
186 {
187 	struct hinic_hwdev *hwdev = nic_dev->hwdev;
188 	struct hinic_hwif *hwif = hwdev->hwif;
189 	struct pci_dev *pdev = hwif->pdev;
190 	int i;
191 
192 	for (i = 0; i < skb_shinfo(skb)->nr_frags ; i++)
193 		dma_unmap_page(&pdev->dev, hinic_sge_to_dma(&sges[i + 1]),
194 			       sges[i + 1].len, DMA_TO_DEVICE);
195 
196 	dma_unmap_single(&pdev->dev, hinic_sge_to_dma(&sges[0]), sges[0].len,
197 			 DMA_TO_DEVICE);
198 }
199 
200 static void get_inner_l3_l4_type(struct sk_buff *skb, union hinic_l3 *ip,
201 				 union hinic_l4 *l4,
202 				 enum hinic_offload_type offload_type,
203 				 enum hinic_l3_offload_type *l3_type,
204 				 u8 *l4_proto)
205 {
206 	u8 *exthdr;
207 
208 	if (ip->v4->version == 4) {
209 		*l3_type = (offload_type == TX_OFFLOAD_CSUM) ?
210 			   IPV4_PKT_NO_CHKSUM_OFFLOAD :
211 			   IPV4_PKT_WITH_CHKSUM_OFFLOAD;
212 		*l4_proto = ip->v4->protocol;
213 	} else if (ip->v4->version == 6) {
214 		*l3_type = IPV6_PKT;
215 		exthdr = ip->hdr + sizeof(*ip->v6);
216 		*l4_proto = ip->v6->nexthdr;
217 		if (exthdr != l4->hdr) {
218 			int start = exthdr - skb->data;
219 			__be16 frag_off;
220 
221 			ipv6_skip_exthdr(skb, start, l4_proto, &frag_off);
222 		}
223 	} else {
224 		*l3_type = L3TYPE_UNKNOWN;
225 		*l4_proto = 0;
226 	}
227 }
228 
229 static void get_inner_l4_info(struct sk_buff *skb, union hinic_l4 *l4,
230 			      enum hinic_offload_type offload_type, u8 l4_proto,
231 			      enum hinic_l4_offload_type *l4_offload,
232 			      u32 *l4_len, u32 *offset)
233 {
234 	*l4_offload = OFFLOAD_DISABLE;
235 	*offset = 0;
236 	*l4_len = 0;
237 
238 	switch (l4_proto) {
239 	case IPPROTO_TCP:
240 		*l4_offload = TCP_OFFLOAD_ENABLE;
241 		/* doff in unit of 4B */
242 		*l4_len = l4->tcp->doff * 4;
243 		*offset = *l4_len + TRANSPORT_OFFSET(l4->hdr, skb);
244 		break;
245 
246 	case IPPROTO_UDP:
247 		*l4_offload = UDP_OFFLOAD_ENABLE;
248 		*l4_len = sizeof(struct udphdr);
249 		*offset = TRANSPORT_OFFSET(l4->hdr, skb);
250 		break;
251 
252 	case IPPROTO_SCTP:
253 		/* only csum offload support sctp */
254 		if (offload_type != TX_OFFLOAD_CSUM)
255 			break;
256 
257 		*l4_offload = SCTP_OFFLOAD_ENABLE;
258 		*l4_len = sizeof(struct sctphdr);
259 		*offset = TRANSPORT_OFFSET(l4->hdr, skb);
260 		break;
261 
262 	default:
263 		break;
264 	}
265 }
266 
267 static __sum16 csum_magic(union hinic_l3 *ip, unsigned short proto)
268 {
269 	return (ip->v4->version == 4) ?
270 		csum_tcpudp_magic(ip->v4->saddr, ip->v4->daddr, 0, proto, 0) :
271 		csum_ipv6_magic(&ip->v6->saddr, &ip->v6->daddr, 0, proto, 0);
272 }
273 
274 static int offload_tso(struct hinic_sq_task *task, u32 *queue_info,
275 		       struct sk_buff *skb)
276 {
277 	u32 offset, l4_len, ip_identify, network_hdr_len;
278 	enum hinic_l3_offload_type l3_offload;
279 	enum hinic_l4_offload_type l4_offload;
280 	union hinic_l3 ip;
281 	union hinic_l4 l4;
282 	u8 l4_proto;
283 
284 	if (!skb_is_gso(skb))
285 		return 0;
286 
287 	if (skb_cow_head(skb, 0) < 0)
288 		return -EPROTONOSUPPORT;
289 
290 	if (skb->encapsulation) {
291 		u32 gso_type = skb_shinfo(skb)->gso_type;
292 		u32 tunnel_type = 0;
293 		u32 l4_tunnel_len;
294 
295 		ip.hdr = skb_network_header(skb);
296 		l4.hdr = skb_transport_header(skb);
297 		network_hdr_len = skb_inner_network_header_len(skb);
298 
299 		if (ip.v4->version == 4) {
300 			ip.v4->tot_len = 0;
301 			l3_offload = IPV4_PKT_WITH_CHKSUM_OFFLOAD;
302 		} else if (ip.v4->version == 6) {
303 			l3_offload = IPV6_PKT;
304 		} else {
305 			l3_offload = 0;
306 		}
307 
308 		hinic_task_set_outter_l3(task, l3_offload,
309 					 skb_network_header_len(skb));
310 
311 		if (gso_type & SKB_GSO_UDP_TUNNEL_CSUM) {
312 			l4.udp->check = ~csum_magic(&ip, IPPROTO_UDP);
313 			tunnel_type = TUNNEL_UDP_CSUM;
314 		} else if (gso_type & SKB_GSO_UDP_TUNNEL) {
315 			tunnel_type = TUNNEL_UDP_NO_CSUM;
316 		}
317 
318 		l4_tunnel_len = skb_inner_network_offset(skb) -
319 				skb_transport_offset(skb);
320 		hinic_task_set_tunnel_l4(task, tunnel_type, l4_tunnel_len);
321 
322 		ip.hdr = skb_inner_network_header(skb);
323 		l4.hdr = skb_inner_transport_header(skb);
324 	} else {
325 		ip.hdr = skb_network_header(skb);
326 		l4.hdr = skb_transport_header(skb);
327 		network_hdr_len = skb_network_header_len(skb);
328 	}
329 
330 	/* initialize inner IP header fields */
331 	if (ip.v4->version == 4)
332 		ip.v4->tot_len = 0;
333 	else
334 		ip.v6->payload_len = 0;
335 
336 	get_inner_l3_l4_type(skb, &ip, &l4, TX_OFFLOAD_TSO, &l3_offload,
337 			     &l4_proto);
338 
339 	hinic_task_set_inner_l3(task, l3_offload, network_hdr_len);
340 
341 	ip_identify = 0;
342 	if (l4_proto == IPPROTO_TCP)
343 		l4.tcp->check = ~csum_magic(&ip, IPPROTO_TCP);
344 
345 	get_inner_l4_info(skb, &l4, TX_OFFLOAD_TSO, l4_proto, &l4_offload,
346 			  &l4_len, &offset);
347 
348 	hinic_set_tso_inner_l4(task, queue_info, l4_offload, l4_len, offset,
349 			       ip_identify, skb_shinfo(skb)->gso_size);
350 
351 	return 1;
352 }
353 
354 static int offload_csum(struct hinic_sq_task *task, u32 *queue_info,
355 			struct sk_buff *skb)
356 {
357 	enum hinic_l4_offload_type l4_offload;
358 	u32 offset, l4_len, network_hdr_len;
359 	enum hinic_l3_offload_type l3_type;
360 	union hinic_l3 ip;
361 	union hinic_l4 l4;
362 	u8 l4_proto;
363 
364 	if (skb->ip_summed != CHECKSUM_PARTIAL)
365 		return 0;
366 
367 	if (skb->encapsulation) {
368 		u32 l4_tunnel_len;
369 
370 		ip.hdr = skb_network_header(skb);
371 
372 		if (ip.v4->version == 4)
373 			l3_type = IPV4_PKT_NO_CHKSUM_OFFLOAD;
374 		else if (ip.v4->version == 6)
375 			l3_type = IPV6_PKT;
376 		else
377 			l3_type = L3TYPE_UNKNOWN;
378 
379 		hinic_task_set_outter_l3(task, l3_type,
380 					 skb_network_header_len(skb));
381 
382 		l4_tunnel_len = skb_inner_network_offset(skb) -
383 				skb_transport_offset(skb);
384 
385 		hinic_task_set_tunnel_l4(task, TUNNEL_UDP_NO_CSUM,
386 					 l4_tunnel_len);
387 
388 		ip.hdr = skb_inner_network_header(skb);
389 		l4.hdr = skb_inner_transport_header(skb);
390 		network_hdr_len = skb_inner_network_header_len(skb);
391 	} else {
392 		ip.hdr = skb_network_header(skb);
393 		l4.hdr = skb_transport_header(skb);
394 		network_hdr_len = skb_network_header_len(skb);
395 	}
396 
397 	get_inner_l3_l4_type(skb, &ip, &l4, TX_OFFLOAD_CSUM, &l3_type,
398 			     &l4_proto);
399 
400 	hinic_task_set_inner_l3(task, l3_type, network_hdr_len);
401 
402 	get_inner_l4_info(skb, &l4, TX_OFFLOAD_CSUM, l4_proto, &l4_offload,
403 			  &l4_len, &offset);
404 
405 	hinic_set_cs_inner_l4(task, queue_info, l4_offload, l4_len, offset);
406 
407 	return 1;
408 }
409 
410 static void offload_vlan(struct hinic_sq_task *task, u32 *queue_info,
411 			 u16 vlan_tag, u16 vlan_pri)
412 {
413 	task->pkt_info0 |= HINIC_SQ_TASK_INFO0_SET(vlan_tag, VLAN_TAG) |
414 				HINIC_SQ_TASK_INFO0_SET(1U, VLAN_OFFLOAD);
415 
416 	*queue_info |= HINIC_SQ_CTRL_SET(vlan_pri, QUEUE_INFO_PRI);
417 }
418 
419 static int hinic_tx_offload(struct sk_buff *skb, struct hinic_sq_task *task,
420 			    u32 *queue_info)
421 {
422 	enum hinic_offload_type offload = 0;
423 	u16 vlan_tag;
424 	int enabled;
425 
426 	enabled = offload_tso(task, queue_info, skb);
427 	if (enabled > 0) {
428 		offload |= TX_OFFLOAD_TSO;
429 	} else if (enabled == 0) {
430 		enabled = offload_csum(task, queue_info, skb);
431 		if (enabled)
432 			offload |= TX_OFFLOAD_CSUM;
433 	} else {
434 		return -EPROTONOSUPPORT;
435 	}
436 
437 	if (unlikely(skb_vlan_tag_present(skb))) {
438 		vlan_tag = skb_vlan_tag_get(skb);
439 		offload_vlan(task, queue_info, vlan_tag,
440 			     vlan_tag >> VLAN_PRIO_SHIFT);
441 		offload |= TX_OFFLOAD_VLAN;
442 	}
443 
444 	if (offload)
445 		hinic_task_set_l2hdr(task, skb_network_offset(skb));
446 
447 	/* payload offset should not more than 221 */
448 	if (HINIC_SQ_CTRL_GET(*queue_info, QUEUE_INFO_PLDOFF) >
449 	    MAX_PAYLOAD_OFFSET) {
450 		return -EPROTONOSUPPORT;
451 	}
452 
453 	/* mss should not less than 80 */
454 	if (HINIC_SQ_CTRL_GET(*queue_info, QUEUE_INFO_MSS) < HINIC_MSS_MIN) {
455 		*queue_info = HINIC_SQ_CTRL_CLEAR(*queue_info, QUEUE_INFO_MSS);
456 		*queue_info |= HINIC_SQ_CTRL_SET(HINIC_MSS_MIN, QUEUE_INFO_MSS);
457 	}
458 
459 	return 0;
460 }
461 
462 netdev_tx_t hinic_xmit_frame(struct sk_buff *skb, struct net_device *netdev)
463 {
464 	struct hinic_dev *nic_dev = netdev_priv(netdev);
465 	u16 prod_idx, q_id = skb->queue_mapping;
466 	struct netdev_queue *netdev_txq;
467 	int nr_sges, err = NETDEV_TX_OK;
468 	struct hinic_sq_wqe *sq_wqe;
469 	unsigned int wqe_size;
470 	struct hinic_txq *txq;
471 	struct hinic_qp *qp;
472 
473 	txq = &nic_dev->txqs[q_id];
474 	qp = container_of(txq->sq, struct hinic_qp, sq);
475 
476 	if (skb->len < MIN_SKB_LEN) {
477 		if (skb_pad(skb, MIN_SKB_LEN - skb->len)) {
478 			netdev_err(netdev, "Failed to pad skb\n");
479 			goto update_error_stats;
480 		}
481 
482 		skb->len = MIN_SKB_LEN;
483 	}
484 
485 	nr_sges = skb_shinfo(skb)->nr_frags + 1;
486 	if (nr_sges > 17) {
487 		u64_stats_update_begin(&txq->txq_stats.syncp);
488 		txq->txq_stats.big_frags_pkts++;
489 		u64_stats_update_end(&txq->txq_stats.syncp);
490 	}
491 
492 	if (nr_sges > txq->max_sges) {
493 		netdev_err(netdev, "Too many Tx sges\n");
494 		goto skb_error;
495 	}
496 
497 	err = tx_map_skb(nic_dev, skb, txq->sges);
498 	if (err)
499 		goto skb_error;
500 
501 	wqe_size = HINIC_SQ_WQE_SIZE(nr_sges);
502 
503 	sq_wqe = hinic_sq_get_wqe(txq->sq, wqe_size, &prod_idx);
504 	if (!sq_wqe) {
505 		netif_stop_subqueue(netdev, qp->q_id);
506 
507 		/* Check for the case free_tx_poll is called in another cpu
508 		 * and we stopped the subqueue after free_tx_poll check.
509 		 */
510 		sq_wqe = hinic_sq_get_wqe(txq->sq, wqe_size, &prod_idx);
511 		if (sq_wqe) {
512 			netif_wake_subqueue(nic_dev->netdev, qp->q_id);
513 			goto process_sq_wqe;
514 		}
515 
516 		tx_unmap_skb(nic_dev, skb, txq->sges);
517 
518 		u64_stats_update_begin(&txq->txq_stats.syncp);
519 		txq->txq_stats.tx_busy++;
520 		u64_stats_update_end(&txq->txq_stats.syncp);
521 		err = NETDEV_TX_BUSY;
522 		wqe_size = 0;
523 		goto flush_skbs;
524 	}
525 
526 process_sq_wqe:
527 	hinic_sq_prepare_wqe(txq->sq, prod_idx, sq_wqe, txq->sges, nr_sges);
528 
529 	err = hinic_tx_offload(skb, &sq_wqe->task, &sq_wqe->ctrl.queue_info);
530 	if (err)
531 		goto offload_error;
532 
533 	hinic_sq_write_wqe(txq->sq, prod_idx, sq_wqe, skb, wqe_size);
534 
535 flush_skbs:
536 	netdev_txq = netdev_get_tx_queue(netdev, q_id);
537 	if ((!netdev_xmit_more()) || (netif_xmit_stopped(netdev_txq)))
538 		hinic_sq_write_db(txq->sq, prod_idx, wqe_size, 0);
539 
540 	return err;
541 
542 offload_error:
543 	hinic_sq_return_wqe(txq->sq, wqe_size);
544 	tx_unmap_skb(nic_dev, skb, txq->sges);
545 
546 skb_error:
547 	dev_kfree_skb_any(skb);
548 
549 update_error_stats:
550 	u64_stats_update_begin(&txq->txq_stats.syncp);
551 	txq->txq_stats.tx_dropped++;
552 	u64_stats_update_end(&txq->txq_stats.syncp);
553 
554 	return NETDEV_TX_OK;
555 }
556 
557 /**
558  * tx_free_skb - unmap and free skb
559  * @nic_dev: nic device
560  * @skb: the skb
561  * @sges: the sges that are connected to the skb
562  **/
563 static void tx_free_skb(struct hinic_dev *nic_dev, struct sk_buff *skb,
564 			struct hinic_sge *sges)
565 {
566 	tx_unmap_skb(nic_dev, skb, sges);
567 
568 	dev_kfree_skb_any(skb);
569 }
570 
571 /**
572  * free_all_rx_skbs - free all skbs in tx queue
573  * @txq: tx queue
574  **/
575 static void free_all_tx_skbs(struct hinic_txq *txq)
576 {
577 	struct hinic_dev *nic_dev = netdev_priv(txq->netdev);
578 	struct hinic_sq *sq = txq->sq;
579 	struct hinic_sq_wqe *sq_wqe;
580 	unsigned int wqe_size;
581 	struct sk_buff *skb;
582 	int nr_sges;
583 	u16 ci;
584 
585 	while ((sq_wqe = hinic_sq_read_wqebb(sq, &skb, &wqe_size, &ci))) {
586 		sq_wqe = hinic_sq_read_wqe(sq, &skb, wqe_size, &ci);
587 		if (!sq_wqe)
588 			break;
589 
590 		nr_sges = skb_shinfo(skb)->nr_frags + 1;
591 
592 		hinic_sq_get_sges(sq_wqe, txq->free_sges, nr_sges);
593 
594 		hinic_sq_put_wqe(sq, wqe_size);
595 
596 		tx_free_skb(nic_dev, skb, txq->free_sges);
597 	}
598 }
599 
600 /**
601  * free_tx_poll - free finished tx skbs in tx queue that connected to napi
602  * @napi: napi
603  * @budget: number of tx
604  *
605  * Return 0 - Success, negative - Failure
606  **/
607 static int free_tx_poll(struct napi_struct *napi, int budget)
608 {
609 	struct hinic_txq *txq = container_of(napi, struct hinic_txq, napi);
610 	struct hinic_qp *qp = container_of(txq->sq, struct hinic_qp, sq);
611 	struct hinic_dev *nic_dev = netdev_priv(txq->netdev);
612 	struct netdev_queue *netdev_txq;
613 	struct hinic_sq *sq = txq->sq;
614 	struct hinic_wq *wq = sq->wq;
615 	struct hinic_sq_wqe *sq_wqe;
616 	unsigned int wqe_size;
617 	int nr_sges, pkts = 0;
618 	struct sk_buff *skb;
619 	u64 tx_bytes = 0;
620 	u16 hw_ci, sw_ci;
621 
622 	do {
623 		hw_ci = HW_CONS_IDX(sq) & wq->mask;
624 
625 		/* Reading a WQEBB to get real WQE size and consumer index. */
626 		sq_wqe = hinic_sq_read_wqebb(sq, &skb, &wqe_size, &sw_ci);
627 		if ((!sq_wqe) ||
628 		    (((hw_ci - sw_ci) & wq->mask) * wq->wqebb_size < wqe_size))
629 			break;
630 
631 		/* If this WQE have multiple WQEBBs, we will read again to get
632 		 * full size WQE.
633 		 */
634 		if (wqe_size > wq->wqebb_size) {
635 			sq_wqe = hinic_sq_read_wqe(sq, &skb, wqe_size, &sw_ci);
636 			if (unlikely(!sq_wqe))
637 				break;
638 		}
639 
640 		tx_bytes += skb->len;
641 		pkts++;
642 
643 		nr_sges = skb_shinfo(skb)->nr_frags + 1;
644 
645 		hinic_sq_get_sges(sq_wqe, txq->free_sges, nr_sges);
646 
647 		hinic_sq_put_wqe(sq, wqe_size);
648 
649 		tx_free_skb(nic_dev, skb, txq->free_sges);
650 	} while (pkts < budget);
651 
652 	if (__netif_subqueue_stopped(nic_dev->netdev, qp->q_id) &&
653 	    hinic_get_sq_free_wqebbs(sq) >= HINIC_MIN_TX_NUM_WQEBBS(sq)) {
654 		netdev_txq = netdev_get_tx_queue(txq->netdev, qp->q_id);
655 
656 		__netif_tx_lock(netdev_txq, smp_processor_id());
657 
658 		netif_wake_subqueue(nic_dev->netdev, qp->q_id);
659 
660 		__netif_tx_unlock(netdev_txq);
661 
662 		u64_stats_update_begin(&txq->txq_stats.syncp);
663 		txq->txq_stats.tx_wake++;
664 		u64_stats_update_end(&txq->txq_stats.syncp);
665 	}
666 
667 	u64_stats_update_begin(&txq->txq_stats.syncp);
668 	txq->txq_stats.bytes += tx_bytes;
669 	txq->txq_stats.pkts += pkts;
670 	u64_stats_update_end(&txq->txq_stats.syncp);
671 
672 	if (pkts < budget) {
673 		napi_complete(napi);
674 		hinic_hwdev_set_msix_state(nic_dev->hwdev,
675 					   sq->msix_entry,
676 					   HINIC_MSIX_ENABLE);
677 		return pkts;
678 	}
679 
680 	return budget;
681 }
682 
683 static void tx_napi_add(struct hinic_txq *txq, int weight)
684 {
685 	netif_napi_add(txq->netdev, &txq->napi, free_tx_poll, weight);
686 	napi_enable(&txq->napi);
687 }
688 
689 static void tx_napi_del(struct hinic_txq *txq)
690 {
691 	napi_disable(&txq->napi);
692 	netif_napi_del(&txq->napi);
693 }
694 
695 static irqreturn_t tx_irq(int irq, void *data)
696 {
697 	struct hinic_txq *txq = data;
698 	struct hinic_dev *nic_dev;
699 
700 	nic_dev = netdev_priv(txq->netdev);
701 
702 	/* Disable the interrupt until napi will be completed */
703 	hinic_hwdev_set_msix_state(nic_dev->hwdev,
704 				   txq->sq->msix_entry,
705 				   HINIC_MSIX_DISABLE);
706 
707 	hinic_hwdev_msix_cnt_set(nic_dev->hwdev, txq->sq->msix_entry);
708 
709 	napi_schedule(&txq->napi);
710 	return IRQ_HANDLED;
711 }
712 
713 static int tx_request_irq(struct hinic_txq *txq)
714 {
715 	struct hinic_dev *nic_dev = netdev_priv(txq->netdev);
716 	struct hinic_hwdev *hwdev = nic_dev->hwdev;
717 	struct hinic_hwif *hwif = hwdev->hwif;
718 	struct pci_dev *pdev = hwif->pdev;
719 	struct hinic_sq *sq = txq->sq;
720 	int err;
721 
722 	tx_napi_add(txq, nic_dev->tx_weight);
723 
724 	hinic_hwdev_msix_set(nic_dev->hwdev, sq->msix_entry,
725 			     TX_IRQ_NO_PENDING, TX_IRQ_NO_COALESC,
726 			     TX_IRQ_NO_LLI_TIMER, TX_IRQ_NO_CREDIT,
727 			     TX_IRQ_NO_RESEND_TIMER);
728 
729 	err = request_irq(sq->irq, tx_irq, 0, txq->irq_name, txq);
730 	if (err) {
731 		dev_err(&pdev->dev, "Failed to request Tx irq\n");
732 		tx_napi_del(txq);
733 		return err;
734 	}
735 
736 	return 0;
737 }
738 
739 static void tx_free_irq(struct hinic_txq *txq)
740 {
741 	struct hinic_sq *sq = txq->sq;
742 
743 	free_irq(sq->irq, txq);
744 	tx_napi_del(txq);
745 }
746 
747 /**
748  * hinic_init_txq - Initialize the Tx Queue
749  * @txq: Logical Tx Queue
750  * @sq: Hardware Tx Queue to connect the Logical queue with
751  * @netdev: network device to connect the Logical queue with
752  *
753  * Return 0 - Success, negative - Failure
754  **/
755 int hinic_init_txq(struct hinic_txq *txq, struct hinic_sq *sq,
756 		   struct net_device *netdev)
757 {
758 	struct hinic_qp *qp = container_of(sq, struct hinic_qp, sq);
759 	struct hinic_dev *nic_dev = netdev_priv(netdev);
760 	struct hinic_hwdev *hwdev = nic_dev->hwdev;
761 	int err, irqname_len;
762 	size_t sges_size;
763 
764 	txq->netdev = netdev;
765 	txq->sq = sq;
766 
767 	txq_stats_init(txq);
768 
769 	txq->max_sges = HINIC_MAX_SQ_BUFDESCS;
770 
771 	sges_size = txq->max_sges * sizeof(*txq->sges);
772 	txq->sges = devm_kzalloc(&netdev->dev, sges_size, GFP_KERNEL);
773 	if (!txq->sges)
774 		return -ENOMEM;
775 
776 	sges_size = txq->max_sges * sizeof(*txq->free_sges);
777 	txq->free_sges = devm_kzalloc(&netdev->dev, sges_size, GFP_KERNEL);
778 	if (!txq->free_sges) {
779 		err = -ENOMEM;
780 		goto err_alloc_free_sges;
781 	}
782 
783 	irqname_len = snprintf(NULL, 0, "hinic_txq%d", qp->q_id) + 1;
784 	txq->irq_name = devm_kzalloc(&netdev->dev, irqname_len, GFP_KERNEL);
785 	if (!txq->irq_name) {
786 		err = -ENOMEM;
787 		goto err_alloc_irqname;
788 	}
789 
790 	sprintf(txq->irq_name, "hinic_txq%d", qp->q_id);
791 
792 	err = hinic_hwdev_hw_ci_addr_set(hwdev, sq, CI_UPDATE_NO_PENDING,
793 					 CI_UPDATE_NO_COALESC);
794 	if (err)
795 		goto err_hw_ci;
796 
797 	err = tx_request_irq(txq);
798 	if (err) {
799 		netdev_err(netdev, "Failed to request Tx irq\n");
800 		goto err_req_tx_irq;
801 	}
802 
803 	return 0;
804 
805 err_req_tx_irq:
806 err_hw_ci:
807 	devm_kfree(&netdev->dev, txq->irq_name);
808 
809 err_alloc_irqname:
810 	devm_kfree(&netdev->dev, txq->free_sges);
811 
812 err_alloc_free_sges:
813 	devm_kfree(&netdev->dev, txq->sges);
814 	return err;
815 }
816 
817 /**
818  * hinic_clean_txq - Clean the Tx Queue
819  * @txq: Logical Tx Queue
820  **/
821 void hinic_clean_txq(struct hinic_txq *txq)
822 {
823 	struct net_device *netdev = txq->netdev;
824 
825 	tx_free_irq(txq);
826 
827 	free_all_tx_skbs(txq);
828 
829 	devm_kfree(&netdev->dev, txq->irq_name);
830 	devm_kfree(&netdev->dev, txq->free_sges);
831 	devm_kfree(&netdev->dev, txq->sges);
832 }
833