xref: /linux/drivers/net/ethernet/cavium/thunder/nicvf_queues.c (revision cc622420798c4bcf093785d872525087a7798db9)
1 /*
2  * Copyright (C) 2015 Cavium, Inc.
3  *
4  * This program is free software; you can redistribute it and/or modify it
5  * under the terms of version 2 of the GNU General Public License
6  * as published by the Free Software Foundation.
7  */
8 
9 #include <linux/pci.h>
10 #include <linux/netdevice.h>
11 #include <linux/ip.h>
12 #include <linux/etherdevice.h>
13 #include <net/ip.h>
14 #include <net/tso.h>
15 
16 #include "nic_reg.h"
17 #include "nic.h"
18 #include "q_struct.h"
19 #include "nicvf_queues.h"
20 
21 static void nicvf_get_page(struct nicvf *nic)
22 {
23 	if (!nic->rb_pageref || !nic->rb_page)
24 		return;
25 
26 	atomic_add(nic->rb_pageref, &nic->rb_page->_count);
27 	nic->rb_pageref = 0;
28 }
29 
30 /* Poll a register for a specific value */
31 static int nicvf_poll_reg(struct nicvf *nic, int qidx,
32 			  u64 reg, int bit_pos, int bits, int val)
33 {
34 	u64 bit_mask;
35 	u64 reg_val;
36 	int timeout = 10;
37 
38 	bit_mask = (1ULL << bits) - 1;
39 	bit_mask = (bit_mask << bit_pos);
40 
41 	while (timeout) {
42 		reg_val = nicvf_queue_reg_read(nic, reg, qidx);
43 		if (((reg_val & bit_mask) >> bit_pos) == val)
44 			return 0;
45 		usleep_range(1000, 2000);
46 		timeout--;
47 	}
48 	netdev_err(nic->netdev, "Poll on reg 0x%llx failed\n", reg);
49 	return 1;
50 }
51 
52 /* Allocate memory for a queue's descriptors */
53 static int nicvf_alloc_q_desc_mem(struct nicvf *nic, struct q_desc_mem *dmem,
54 				  int q_len, int desc_size, int align_bytes)
55 {
56 	dmem->q_len = q_len;
57 	dmem->size = (desc_size * q_len) + align_bytes;
58 	/* Save address, need it while freeing */
59 	dmem->unalign_base = dma_zalloc_coherent(&nic->pdev->dev, dmem->size,
60 						&dmem->dma, GFP_KERNEL);
61 	if (!dmem->unalign_base)
62 		return -ENOMEM;
63 
64 	/* Align memory address for 'align_bytes' */
65 	dmem->phys_base = NICVF_ALIGNED_ADDR((u64)dmem->dma, align_bytes);
66 	dmem->base = dmem->unalign_base + (dmem->phys_base - dmem->dma);
67 	return 0;
68 }
69 
70 /* Free queue's descriptor memory */
71 static void nicvf_free_q_desc_mem(struct nicvf *nic, struct q_desc_mem *dmem)
72 {
73 	if (!dmem)
74 		return;
75 
76 	dma_free_coherent(&nic->pdev->dev, dmem->size,
77 			  dmem->unalign_base, dmem->dma);
78 	dmem->unalign_base = NULL;
79 	dmem->base = NULL;
80 }
81 
82 /* Allocate buffer for packet reception
83  * HW returns memory address where packet is DMA'ed but not a pointer
84  * into RBDR ring, so save buffer address at the start of fragment and
85  * align the start address to a cache aligned address
86  */
87 static inline int nicvf_alloc_rcv_buffer(struct nicvf *nic, gfp_t gfp,
88 					 u32 buf_len, u64 **rbuf)
89 {
90 	int order = (PAGE_SIZE <= 4096) ?  PAGE_ALLOC_COSTLY_ORDER : 0;
91 
92 	/* Check if request can be accomodated in previous allocated page */
93 	if (nic->rb_page &&
94 	    ((nic->rb_page_offset + buf_len) < (PAGE_SIZE << order))) {
95 		nic->rb_pageref++;
96 		goto ret;
97 	}
98 
99 	nicvf_get_page(nic);
100 	nic->rb_page = NULL;
101 
102 	/* Allocate a new page */
103 	if (!nic->rb_page) {
104 		nic->rb_page = alloc_pages(gfp | __GFP_COMP | __GFP_NOWARN,
105 					   order);
106 		if (!nic->rb_page) {
107 			nic->drv_stats.rcv_buffer_alloc_failures++;
108 			return -ENOMEM;
109 		}
110 		nic->rb_page_offset = 0;
111 	}
112 
113 ret:
114 	*rbuf = (u64 *)((u64)page_address(nic->rb_page) + nic->rb_page_offset);
115 	nic->rb_page_offset += buf_len;
116 
117 	return 0;
118 }
119 
120 /* Build skb around receive buffer */
121 static struct sk_buff *nicvf_rb_ptr_to_skb(struct nicvf *nic,
122 					   u64 rb_ptr, int len)
123 {
124 	void *data;
125 	struct sk_buff *skb;
126 
127 	data = phys_to_virt(rb_ptr);
128 
129 	/* Now build an skb to give to stack */
130 	skb = build_skb(data, RCV_FRAG_LEN);
131 	if (!skb) {
132 		put_page(virt_to_page(data));
133 		return NULL;
134 	}
135 
136 	prefetch(skb->data);
137 	return skb;
138 }
139 
140 /* Allocate RBDR ring and populate receive buffers */
141 static int  nicvf_init_rbdr(struct nicvf *nic, struct rbdr *rbdr,
142 			    int ring_len, int buf_size)
143 {
144 	int idx;
145 	u64 *rbuf;
146 	struct rbdr_entry_t *desc;
147 	int err;
148 
149 	err = nicvf_alloc_q_desc_mem(nic, &rbdr->dmem, ring_len,
150 				     sizeof(struct rbdr_entry_t),
151 				     NICVF_RCV_BUF_ALIGN_BYTES);
152 	if (err)
153 		return err;
154 
155 	rbdr->desc = rbdr->dmem.base;
156 	/* Buffer size has to be in multiples of 128 bytes */
157 	rbdr->dma_size = buf_size;
158 	rbdr->enable = true;
159 	rbdr->thresh = RBDR_THRESH;
160 
161 	nic->rb_page = NULL;
162 	for (idx = 0; idx < ring_len; idx++) {
163 		err = nicvf_alloc_rcv_buffer(nic, GFP_KERNEL, RCV_FRAG_LEN,
164 					     &rbuf);
165 		if (err)
166 			return err;
167 
168 		desc = GET_RBDR_DESC(rbdr, idx);
169 		desc->buf_addr = virt_to_phys(rbuf) >> NICVF_RCV_BUF_ALIGN;
170 	}
171 
172 	nicvf_get_page(nic);
173 
174 	return 0;
175 }
176 
177 /* Free RBDR ring and its receive buffers */
178 static void nicvf_free_rbdr(struct nicvf *nic, struct rbdr *rbdr)
179 {
180 	int head, tail;
181 	u64 buf_addr;
182 	struct rbdr_entry_t *desc;
183 
184 	if (!rbdr)
185 		return;
186 
187 	rbdr->enable = false;
188 	if (!rbdr->dmem.base)
189 		return;
190 
191 	head = rbdr->head;
192 	tail = rbdr->tail;
193 
194 	/* Free SKBs */
195 	while (head != tail) {
196 		desc = GET_RBDR_DESC(rbdr, head);
197 		buf_addr = desc->buf_addr << NICVF_RCV_BUF_ALIGN;
198 		put_page(virt_to_page(phys_to_virt(buf_addr)));
199 		head++;
200 		head &= (rbdr->dmem.q_len - 1);
201 	}
202 	/* Free SKB of tail desc */
203 	desc = GET_RBDR_DESC(rbdr, tail);
204 	buf_addr = desc->buf_addr << NICVF_RCV_BUF_ALIGN;
205 	put_page(virt_to_page(phys_to_virt(buf_addr)));
206 
207 	/* Free RBDR ring */
208 	nicvf_free_q_desc_mem(nic, &rbdr->dmem);
209 }
210 
211 /* Refill receive buffer descriptors with new buffers.
212  */
213 static void nicvf_refill_rbdr(struct nicvf *nic, gfp_t gfp)
214 {
215 	struct queue_set *qs = nic->qs;
216 	int rbdr_idx = qs->rbdr_cnt;
217 	int tail, qcount;
218 	int refill_rb_cnt;
219 	struct rbdr *rbdr;
220 	struct rbdr_entry_t *desc;
221 	u64 *rbuf;
222 	int new_rb = 0;
223 
224 refill:
225 	if (!rbdr_idx)
226 		return;
227 	rbdr_idx--;
228 	rbdr = &qs->rbdr[rbdr_idx];
229 	/* Check if it's enabled */
230 	if (!rbdr->enable)
231 		goto next_rbdr;
232 
233 	/* Get no of desc's to be refilled */
234 	qcount = nicvf_queue_reg_read(nic, NIC_QSET_RBDR_0_1_STATUS0, rbdr_idx);
235 	qcount &= 0x7FFFF;
236 	/* Doorbell can be ringed with a max of ring size minus 1 */
237 	if (qcount >= (qs->rbdr_len - 1))
238 		goto next_rbdr;
239 	else
240 		refill_rb_cnt = qs->rbdr_len - qcount - 1;
241 
242 	/* Start filling descs from tail */
243 	tail = nicvf_queue_reg_read(nic, NIC_QSET_RBDR_0_1_TAIL, rbdr_idx) >> 3;
244 	while (refill_rb_cnt) {
245 		tail++;
246 		tail &= (rbdr->dmem.q_len - 1);
247 
248 		if (nicvf_alloc_rcv_buffer(nic, gfp, RCV_FRAG_LEN, &rbuf))
249 			break;
250 
251 		desc = GET_RBDR_DESC(rbdr, tail);
252 		desc->buf_addr = virt_to_phys(rbuf) >> NICVF_RCV_BUF_ALIGN;
253 		refill_rb_cnt--;
254 		new_rb++;
255 	}
256 
257 	nicvf_get_page(nic);
258 
259 	/* make sure all memory stores are done before ringing doorbell */
260 	smp_wmb();
261 
262 	/* Check if buffer allocation failed */
263 	if (refill_rb_cnt)
264 		nic->rb_alloc_fail = true;
265 	else
266 		nic->rb_alloc_fail = false;
267 
268 	/* Notify HW */
269 	nicvf_queue_reg_write(nic, NIC_QSET_RBDR_0_1_DOOR,
270 			      rbdr_idx, new_rb);
271 next_rbdr:
272 	/* Re-enable RBDR interrupts only if buffer allocation is success */
273 	if (!nic->rb_alloc_fail && rbdr->enable)
274 		nicvf_enable_intr(nic, NICVF_INTR_RBDR, rbdr_idx);
275 
276 	if (rbdr_idx)
277 		goto refill;
278 }
279 
280 /* Alloc rcv buffers in non-atomic mode for better success */
281 void nicvf_rbdr_work(struct work_struct *work)
282 {
283 	struct nicvf *nic = container_of(work, struct nicvf, rbdr_work.work);
284 
285 	nicvf_refill_rbdr(nic, GFP_KERNEL);
286 	if (nic->rb_alloc_fail)
287 		schedule_delayed_work(&nic->rbdr_work, msecs_to_jiffies(10));
288 	else
289 		nic->rb_work_scheduled = false;
290 }
291 
292 /* In Softirq context, alloc rcv buffers in atomic mode */
293 void nicvf_rbdr_task(unsigned long data)
294 {
295 	struct nicvf *nic = (struct nicvf *)data;
296 
297 	nicvf_refill_rbdr(nic, GFP_ATOMIC);
298 	if (nic->rb_alloc_fail) {
299 		nic->rb_work_scheduled = true;
300 		schedule_delayed_work(&nic->rbdr_work, msecs_to_jiffies(10));
301 	}
302 }
303 
304 /* Initialize completion queue */
305 static int nicvf_init_cmp_queue(struct nicvf *nic,
306 				struct cmp_queue *cq, int q_len)
307 {
308 	int err;
309 
310 	err = nicvf_alloc_q_desc_mem(nic, &cq->dmem, q_len, CMP_QUEUE_DESC_SIZE,
311 				     NICVF_CQ_BASE_ALIGN_BYTES);
312 	if (err)
313 		return err;
314 
315 	cq->desc = cq->dmem.base;
316 	cq->thresh = pass1_silicon(nic->pdev) ? 0 : CMP_QUEUE_CQE_THRESH;
317 	nic->cq_coalesce_usecs = (CMP_QUEUE_TIMER_THRESH * 0.05) - 1;
318 
319 	return 0;
320 }
321 
322 static void nicvf_free_cmp_queue(struct nicvf *nic, struct cmp_queue *cq)
323 {
324 	if (!cq)
325 		return;
326 	if (!cq->dmem.base)
327 		return;
328 
329 	nicvf_free_q_desc_mem(nic, &cq->dmem);
330 }
331 
332 /* Initialize transmit queue */
333 static int nicvf_init_snd_queue(struct nicvf *nic,
334 				struct snd_queue *sq, int q_len)
335 {
336 	int err;
337 
338 	err = nicvf_alloc_q_desc_mem(nic, &sq->dmem, q_len, SND_QUEUE_DESC_SIZE,
339 				     NICVF_SQ_BASE_ALIGN_BYTES);
340 	if (err)
341 		return err;
342 
343 	sq->desc = sq->dmem.base;
344 	sq->skbuff = kcalloc(q_len, sizeof(u64), GFP_KERNEL);
345 	if (!sq->skbuff)
346 		return -ENOMEM;
347 	sq->head = 0;
348 	sq->tail = 0;
349 	atomic_set(&sq->free_cnt, q_len - 1);
350 	sq->thresh = SND_QUEUE_THRESH;
351 
352 	/* Preallocate memory for TSO segment's header */
353 	sq->tso_hdrs = dma_alloc_coherent(&nic->pdev->dev,
354 					  q_len * TSO_HEADER_SIZE,
355 					  &sq->tso_hdrs_phys, GFP_KERNEL);
356 	if (!sq->tso_hdrs)
357 		return -ENOMEM;
358 
359 	return 0;
360 }
361 
362 static void nicvf_free_snd_queue(struct nicvf *nic, struct snd_queue *sq)
363 {
364 	if (!sq)
365 		return;
366 	if (!sq->dmem.base)
367 		return;
368 
369 	if (sq->tso_hdrs)
370 		dma_free_coherent(&nic->pdev->dev,
371 				  sq->dmem.q_len * TSO_HEADER_SIZE,
372 				  sq->tso_hdrs, sq->tso_hdrs_phys);
373 
374 	kfree(sq->skbuff);
375 	nicvf_free_q_desc_mem(nic, &sq->dmem);
376 }
377 
378 static void nicvf_reclaim_snd_queue(struct nicvf *nic,
379 				    struct queue_set *qs, int qidx)
380 {
381 	/* Disable send queue */
382 	nicvf_queue_reg_write(nic, NIC_QSET_SQ_0_7_CFG, qidx, 0);
383 	/* Check if SQ is stopped */
384 	if (nicvf_poll_reg(nic, qidx, NIC_QSET_SQ_0_7_STATUS, 21, 1, 0x01))
385 		return;
386 	/* Reset send queue */
387 	nicvf_queue_reg_write(nic, NIC_QSET_SQ_0_7_CFG, qidx, NICVF_SQ_RESET);
388 }
389 
390 static void nicvf_reclaim_rcv_queue(struct nicvf *nic,
391 				    struct queue_set *qs, int qidx)
392 {
393 	union nic_mbx mbx = {};
394 
395 	/* Make sure all packets in the pipeline are written back into mem */
396 	mbx.msg.msg = NIC_MBOX_MSG_RQ_SW_SYNC;
397 	nicvf_send_msg_to_pf(nic, &mbx);
398 }
399 
400 static void nicvf_reclaim_cmp_queue(struct nicvf *nic,
401 				    struct queue_set *qs, int qidx)
402 {
403 	/* Disable timer threshold (doesn't get reset upon CQ reset */
404 	nicvf_queue_reg_write(nic, NIC_QSET_CQ_0_7_CFG2, qidx, 0);
405 	/* Disable completion queue */
406 	nicvf_queue_reg_write(nic, NIC_QSET_CQ_0_7_CFG, qidx, 0);
407 	/* Reset completion queue */
408 	nicvf_queue_reg_write(nic, NIC_QSET_CQ_0_7_CFG, qidx, NICVF_CQ_RESET);
409 }
410 
411 static void nicvf_reclaim_rbdr(struct nicvf *nic,
412 			       struct rbdr *rbdr, int qidx)
413 {
414 	u64 tmp, fifo_state;
415 	int timeout = 10;
416 
417 	/* Save head and tail pointers for feeing up buffers */
418 	rbdr->head = nicvf_queue_reg_read(nic,
419 					  NIC_QSET_RBDR_0_1_HEAD,
420 					  qidx) >> 3;
421 	rbdr->tail = nicvf_queue_reg_read(nic,
422 					  NIC_QSET_RBDR_0_1_TAIL,
423 					  qidx) >> 3;
424 
425 	/* If RBDR FIFO is in 'FAIL' state then do a reset first
426 	 * before relaiming.
427 	 */
428 	fifo_state = nicvf_queue_reg_read(nic, NIC_QSET_RBDR_0_1_STATUS0, qidx);
429 	if (((fifo_state >> 62) & 0x03) == 0x3)
430 		nicvf_queue_reg_write(nic, NIC_QSET_RBDR_0_1_CFG,
431 				      qidx, NICVF_RBDR_RESET);
432 
433 	/* Disable RBDR */
434 	nicvf_queue_reg_write(nic, NIC_QSET_RBDR_0_1_CFG, qidx, 0);
435 	if (nicvf_poll_reg(nic, qidx, NIC_QSET_RBDR_0_1_STATUS0, 62, 2, 0x00))
436 		return;
437 	while (1) {
438 		tmp = nicvf_queue_reg_read(nic,
439 					   NIC_QSET_RBDR_0_1_PREFETCH_STATUS,
440 					   qidx);
441 		if ((tmp & 0xFFFFFFFF) == ((tmp >> 32) & 0xFFFFFFFF))
442 			break;
443 		usleep_range(1000, 2000);
444 		timeout--;
445 		if (!timeout) {
446 			netdev_err(nic->netdev,
447 				   "Failed polling on prefetch status\n");
448 			return;
449 		}
450 	}
451 	nicvf_queue_reg_write(nic, NIC_QSET_RBDR_0_1_CFG,
452 			      qidx, NICVF_RBDR_RESET);
453 
454 	if (nicvf_poll_reg(nic, qidx, NIC_QSET_RBDR_0_1_STATUS0, 62, 2, 0x02))
455 		return;
456 	nicvf_queue_reg_write(nic, NIC_QSET_RBDR_0_1_CFG, qidx, 0x00);
457 	if (nicvf_poll_reg(nic, qidx, NIC_QSET_RBDR_0_1_STATUS0, 62, 2, 0x00))
458 		return;
459 }
460 
461 void nicvf_config_vlan_stripping(struct nicvf *nic, netdev_features_t features)
462 {
463 	u64 rq_cfg;
464 	int sqs;
465 
466 	rq_cfg = nicvf_queue_reg_read(nic, NIC_QSET_RQ_GEN_CFG, 0);
467 
468 	/* Enable first VLAN stripping */
469 	if (features & NETIF_F_HW_VLAN_CTAG_RX)
470 		rq_cfg |= (1ULL << 25);
471 	else
472 		rq_cfg &= ~(1ULL << 25);
473 	nicvf_queue_reg_write(nic, NIC_QSET_RQ_GEN_CFG, 0, rq_cfg);
474 
475 	/* Configure Secondary Qsets, if any */
476 	for (sqs = 0; sqs < nic->sqs_count; sqs++)
477 		if (nic->snicvf[sqs])
478 			nicvf_queue_reg_write(nic->snicvf[sqs],
479 					      NIC_QSET_RQ_GEN_CFG, 0, rq_cfg);
480 }
481 
482 /* Configures receive queue */
483 static void nicvf_rcv_queue_config(struct nicvf *nic, struct queue_set *qs,
484 				   int qidx, bool enable)
485 {
486 	union nic_mbx mbx = {};
487 	struct rcv_queue *rq;
488 	struct rq_cfg rq_cfg;
489 
490 	rq = &qs->rq[qidx];
491 	rq->enable = enable;
492 
493 	/* Disable receive queue */
494 	nicvf_queue_reg_write(nic, NIC_QSET_RQ_0_7_CFG, qidx, 0);
495 
496 	if (!rq->enable) {
497 		nicvf_reclaim_rcv_queue(nic, qs, qidx);
498 		return;
499 	}
500 
501 	rq->cq_qs = qs->vnic_id;
502 	rq->cq_idx = qidx;
503 	rq->start_rbdr_qs = qs->vnic_id;
504 	rq->start_qs_rbdr_idx = qs->rbdr_cnt - 1;
505 	rq->cont_rbdr_qs = qs->vnic_id;
506 	rq->cont_qs_rbdr_idx = qs->rbdr_cnt - 1;
507 	/* all writes of RBDR data to be loaded into L2 Cache as well*/
508 	rq->caching = 1;
509 
510 	/* Send a mailbox msg to PF to config RQ */
511 	mbx.rq.msg = NIC_MBOX_MSG_RQ_CFG;
512 	mbx.rq.qs_num = qs->vnic_id;
513 	mbx.rq.rq_num = qidx;
514 	mbx.rq.cfg = (rq->caching << 26) | (rq->cq_qs << 19) |
515 			  (rq->cq_idx << 16) | (rq->cont_rbdr_qs << 9) |
516 			  (rq->cont_qs_rbdr_idx << 8) |
517 			  (rq->start_rbdr_qs << 1) | (rq->start_qs_rbdr_idx);
518 	nicvf_send_msg_to_pf(nic, &mbx);
519 
520 	mbx.rq.msg = NIC_MBOX_MSG_RQ_BP_CFG;
521 	mbx.rq.cfg = (1ULL << 63) | (1ULL << 62) | (qs->vnic_id << 0);
522 	nicvf_send_msg_to_pf(nic, &mbx);
523 
524 	/* RQ drop config
525 	 * Enable CQ drop to reserve sufficient CQEs for all tx packets
526 	 */
527 	mbx.rq.msg = NIC_MBOX_MSG_RQ_DROP_CFG;
528 	mbx.rq.cfg = (1ULL << 62) | (RQ_CQ_DROP << 8);
529 	nicvf_send_msg_to_pf(nic, &mbx);
530 
531 	nicvf_queue_reg_write(nic, NIC_QSET_RQ_GEN_CFG, 0, 0x00);
532 	if (!nic->sqs_mode)
533 		nicvf_config_vlan_stripping(nic, nic->netdev->features);
534 
535 	/* Enable Receive queue */
536 	rq_cfg.ena = 1;
537 	rq_cfg.tcp_ena = 0;
538 	nicvf_queue_reg_write(nic, NIC_QSET_RQ_0_7_CFG, qidx, *(u64 *)&rq_cfg);
539 }
540 
541 /* Configures completion queue */
542 void nicvf_cmp_queue_config(struct nicvf *nic, struct queue_set *qs,
543 			    int qidx, bool enable)
544 {
545 	struct cmp_queue *cq;
546 	struct cq_cfg cq_cfg;
547 
548 	cq = &qs->cq[qidx];
549 	cq->enable = enable;
550 
551 	if (!cq->enable) {
552 		nicvf_reclaim_cmp_queue(nic, qs, qidx);
553 		return;
554 	}
555 
556 	/* Reset completion queue */
557 	nicvf_queue_reg_write(nic, NIC_QSET_CQ_0_7_CFG, qidx, NICVF_CQ_RESET);
558 
559 	if (!cq->enable)
560 		return;
561 
562 	spin_lock_init(&cq->lock);
563 	/* Set completion queue base address */
564 	nicvf_queue_reg_write(nic, NIC_QSET_CQ_0_7_BASE,
565 			      qidx, (u64)(cq->dmem.phys_base));
566 
567 	/* Enable Completion queue */
568 	cq_cfg.ena = 1;
569 	cq_cfg.reset = 0;
570 	cq_cfg.caching = 0;
571 	cq_cfg.qsize = CMP_QSIZE;
572 	cq_cfg.avg_con = 0;
573 	nicvf_queue_reg_write(nic, NIC_QSET_CQ_0_7_CFG, qidx, *(u64 *)&cq_cfg);
574 
575 	/* Set threshold value for interrupt generation */
576 	nicvf_queue_reg_write(nic, NIC_QSET_CQ_0_7_THRESH, qidx, cq->thresh);
577 	nicvf_queue_reg_write(nic, NIC_QSET_CQ_0_7_CFG2,
578 			      qidx, CMP_QUEUE_TIMER_THRESH);
579 }
580 
581 /* Configures transmit queue */
582 static void nicvf_snd_queue_config(struct nicvf *nic, struct queue_set *qs,
583 				   int qidx, bool enable)
584 {
585 	union nic_mbx mbx = {};
586 	struct snd_queue *sq;
587 	struct sq_cfg sq_cfg;
588 
589 	sq = &qs->sq[qidx];
590 	sq->enable = enable;
591 
592 	if (!sq->enable) {
593 		nicvf_reclaim_snd_queue(nic, qs, qidx);
594 		return;
595 	}
596 
597 	/* Reset send queue */
598 	nicvf_queue_reg_write(nic, NIC_QSET_SQ_0_7_CFG, qidx, NICVF_SQ_RESET);
599 
600 	sq->cq_qs = qs->vnic_id;
601 	sq->cq_idx = qidx;
602 
603 	/* Send a mailbox msg to PF to config SQ */
604 	mbx.sq.msg = NIC_MBOX_MSG_SQ_CFG;
605 	mbx.sq.qs_num = qs->vnic_id;
606 	mbx.sq.sq_num = qidx;
607 	mbx.sq.sqs_mode = nic->sqs_mode;
608 	mbx.sq.cfg = (sq->cq_qs << 3) | sq->cq_idx;
609 	nicvf_send_msg_to_pf(nic, &mbx);
610 
611 	/* Set queue base address */
612 	nicvf_queue_reg_write(nic, NIC_QSET_SQ_0_7_BASE,
613 			      qidx, (u64)(sq->dmem.phys_base));
614 
615 	/* Enable send queue  & set queue size */
616 	sq_cfg.ena = 1;
617 	sq_cfg.reset = 0;
618 	sq_cfg.ldwb = 0;
619 	sq_cfg.qsize = SND_QSIZE;
620 	sq_cfg.tstmp_bgx_intf = 0;
621 	nicvf_queue_reg_write(nic, NIC_QSET_SQ_0_7_CFG, qidx, *(u64 *)&sq_cfg);
622 
623 	/* Set threshold value for interrupt generation */
624 	nicvf_queue_reg_write(nic, NIC_QSET_SQ_0_7_THRESH, qidx, sq->thresh);
625 
626 	/* Set queue:cpu affinity for better load distribution */
627 	if (cpu_online(qidx)) {
628 		cpumask_set_cpu(qidx, &sq->affinity_mask);
629 		netif_set_xps_queue(nic->netdev,
630 				    &sq->affinity_mask, qidx);
631 	}
632 }
633 
634 /* Configures receive buffer descriptor ring */
635 static void nicvf_rbdr_config(struct nicvf *nic, struct queue_set *qs,
636 			      int qidx, bool enable)
637 {
638 	struct rbdr *rbdr;
639 	struct rbdr_cfg rbdr_cfg;
640 
641 	rbdr = &qs->rbdr[qidx];
642 	nicvf_reclaim_rbdr(nic, rbdr, qidx);
643 	if (!enable)
644 		return;
645 
646 	/* Set descriptor base address */
647 	nicvf_queue_reg_write(nic, NIC_QSET_RBDR_0_1_BASE,
648 			      qidx, (u64)(rbdr->dmem.phys_base));
649 
650 	/* Enable RBDR  & set queue size */
651 	/* Buffer size should be in multiples of 128 bytes */
652 	rbdr_cfg.ena = 1;
653 	rbdr_cfg.reset = 0;
654 	rbdr_cfg.ldwb = 0;
655 	rbdr_cfg.qsize = RBDR_SIZE;
656 	rbdr_cfg.avg_con = 0;
657 	rbdr_cfg.lines = rbdr->dma_size / 128;
658 	nicvf_queue_reg_write(nic, NIC_QSET_RBDR_0_1_CFG,
659 			      qidx, *(u64 *)&rbdr_cfg);
660 
661 	/* Notify HW */
662 	nicvf_queue_reg_write(nic, NIC_QSET_RBDR_0_1_DOOR,
663 			      qidx, qs->rbdr_len - 1);
664 
665 	/* Set threshold value for interrupt generation */
666 	nicvf_queue_reg_write(nic, NIC_QSET_RBDR_0_1_THRESH,
667 			      qidx, rbdr->thresh - 1);
668 }
669 
670 /* Requests PF to assign and enable Qset */
671 void nicvf_qset_config(struct nicvf *nic, bool enable)
672 {
673 	union nic_mbx mbx = {};
674 	struct queue_set *qs = nic->qs;
675 	struct qs_cfg *qs_cfg;
676 
677 	if (!qs) {
678 		netdev_warn(nic->netdev,
679 			    "Qset is still not allocated, don't init queues\n");
680 		return;
681 	}
682 
683 	qs->enable = enable;
684 	qs->vnic_id = nic->vf_id;
685 
686 	/* Send a mailbox msg to PF to config Qset */
687 	mbx.qs.msg = NIC_MBOX_MSG_QS_CFG;
688 	mbx.qs.num = qs->vnic_id;
689 	mbx.qs.sqs_count = nic->sqs_count;
690 
691 	mbx.qs.cfg = 0;
692 	qs_cfg = (struct qs_cfg *)&mbx.qs.cfg;
693 	if (qs->enable) {
694 		qs_cfg->ena = 1;
695 #ifdef __BIG_ENDIAN
696 		qs_cfg->be = 1;
697 #endif
698 		qs_cfg->vnic = qs->vnic_id;
699 	}
700 	nicvf_send_msg_to_pf(nic, &mbx);
701 }
702 
703 static void nicvf_free_resources(struct nicvf *nic)
704 {
705 	int qidx;
706 	struct queue_set *qs = nic->qs;
707 
708 	/* Free receive buffer descriptor ring */
709 	for (qidx = 0; qidx < qs->rbdr_cnt; qidx++)
710 		nicvf_free_rbdr(nic, &qs->rbdr[qidx]);
711 
712 	/* Free completion queue */
713 	for (qidx = 0; qidx < qs->cq_cnt; qidx++)
714 		nicvf_free_cmp_queue(nic, &qs->cq[qidx]);
715 
716 	/* Free send queue */
717 	for (qidx = 0; qidx < qs->sq_cnt; qidx++)
718 		nicvf_free_snd_queue(nic, &qs->sq[qidx]);
719 }
720 
721 static int nicvf_alloc_resources(struct nicvf *nic)
722 {
723 	int qidx;
724 	struct queue_set *qs = nic->qs;
725 
726 	/* Alloc receive buffer descriptor ring */
727 	for (qidx = 0; qidx < qs->rbdr_cnt; qidx++) {
728 		if (nicvf_init_rbdr(nic, &qs->rbdr[qidx], qs->rbdr_len,
729 				    DMA_BUFFER_LEN))
730 			goto alloc_fail;
731 	}
732 
733 	/* Alloc send queue */
734 	for (qidx = 0; qidx < qs->sq_cnt; qidx++) {
735 		if (nicvf_init_snd_queue(nic, &qs->sq[qidx], qs->sq_len))
736 			goto alloc_fail;
737 	}
738 
739 	/* Alloc completion queue */
740 	for (qidx = 0; qidx < qs->cq_cnt; qidx++) {
741 		if (nicvf_init_cmp_queue(nic, &qs->cq[qidx], qs->cq_len))
742 			goto alloc_fail;
743 	}
744 
745 	return 0;
746 alloc_fail:
747 	nicvf_free_resources(nic);
748 	return -ENOMEM;
749 }
750 
751 int nicvf_set_qset_resources(struct nicvf *nic)
752 {
753 	struct queue_set *qs;
754 
755 	qs = devm_kzalloc(&nic->pdev->dev, sizeof(*qs), GFP_KERNEL);
756 	if (!qs)
757 		return -ENOMEM;
758 	nic->qs = qs;
759 
760 	/* Set count of each queue */
761 	qs->rbdr_cnt = RBDR_CNT;
762 	qs->rq_cnt = RCV_QUEUE_CNT;
763 	qs->sq_cnt = SND_QUEUE_CNT;
764 	qs->cq_cnt = CMP_QUEUE_CNT;
765 
766 	/* Set queue lengths */
767 	qs->rbdr_len = RCV_BUF_COUNT;
768 	qs->sq_len = SND_QUEUE_LEN;
769 	qs->cq_len = CMP_QUEUE_LEN;
770 
771 	nic->rx_queues = qs->rq_cnt;
772 	nic->tx_queues = qs->sq_cnt;
773 
774 	return 0;
775 }
776 
777 int nicvf_config_data_transfer(struct nicvf *nic, bool enable)
778 {
779 	bool disable = false;
780 	struct queue_set *qs = nic->qs;
781 	int qidx;
782 
783 	if (!qs)
784 		return 0;
785 
786 	if (enable) {
787 		if (nicvf_alloc_resources(nic))
788 			return -ENOMEM;
789 
790 		for (qidx = 0; qidx < qs->sq_cnt; qidx++)
791 			nicvf_snd_queue_config(nic, qs, qidx, enable);
792 		for (qidx = 0; qidx < qs->cq_cnt; qidx++)
793 			nicvf_cmp_queue_config(nic, qs, qidx, enable);
794 		for (qidx = 0; qidx < qs->rbdr_cnt; qidx++)
795 			nicvf_rbdr_config(nic, qs, qidx, enable);
796 		for (qidx = 0; qidx < qs->rq_cnt; qidx++)
797 			nicvf_rcv_queue_config(nic, qs, qidx, enable);
798 	} else {
799 		for (qidx = 0; qidx < qs->rq_cnt; qidx++)
800 			nicvf_rcv_queue_config(nic, qs, qidx, disable);
801 		for (qidx = 0; qidx < qs->rbdr_cnt; qidx++)
802 			nicvf_rbdr_config(nic, qs, qidx, disable);
803 		for (qidx = 0; qidx < qs->sq_cnt; qidx++)
804 			nicvf_snd_queue_config(nic, qs, qidx, disable);
805 		for (qidx = 0; qidx < qs->cq_cnt; qidx++)
806 			nicvf_cmp_queue_config(nic, qs, qidx, disable);
807 
808 		nicvf_free_resources(nic);
809 	}
810 
811 	return 0;
812 }
813 
814 /* Get a free desc from SQ
815  * returns descriptor ponter & descriptor number
816  */
817 static inline int nicvf_get_sq_desc(struct snd_queue *sq, int desc_cnt)
818 {
819 	int qentry;
820 
821 	qentry = sq->tail;
822 	atomic_sub(desc_cnt, &sq->free_cnt);
823 	sq->tail += desc_cnt;
824 	sq->tail &= (sq->dmem.q_len - 1);
825 
826 	return qentry;
827 }
828 
829 /* Free descriptor back to SQ for future use */
830 void nicvf_put_sq_desc(struct snd_queue *sq, int desc_cnt)
831 {
832 	atomic_add(desc_cnt, &sq->free_cnt);
833 	sq->head += desc_cnt;
834 	sq->head &= (sq->dmem.q_len - 1);
835 }
836 
837 static inline int nicvf_get_nxt_sqentry(struct snd_queue *sq, int qentry)
838 {
839 	qentry++;
840 	qentry &= (sq->dmem.q_len - 1);
841 	return qentry;
842 }
843 
844 void nicvf_sq_enable(struct nicvf *nic, struct snd_queue *sq, int qidx)
845 {
846 	u64 sq_cfg;
847 
848 	sq_cfg = nicvf_queue_reg_read(nic, NIC_QSET_SQ_0_7_CFG, qidx);
849 	sq_cfg |= NICVF_SQ_EN;
850 	nicvf_queue_reg_write(nic, NIC_QSET_SQ_0_7_CFG, qidx, sq_cfg);
851 	/* Ring doorbell so that H/W restarts processing SQEs */
852 	nicvf_queue_reg_write(nic, NIC_QSET_SQ_0_7_DOOR, qidx, 0);
853 }
854 
855 void nicvf_sq_disable(struct nicvf *nic, int qidx)
856 {
857 	u64 sq_cfg;
858 
859 	sq_cfg = nicvf_queue_reg_read(nic, NIC_QSET_SQ_0_7_CFG, qidx);
860 	sq_cfg &= ~NICVF_SQ_EN;
861 	nicvf_queue_reg_write(nic, NIC_QSET_SQ_0_7_CFG, qidx, sq_cfg);
862 }
863 
864 void nicvf_sq_free_used_descs(struct net_device *netdev, struct snd_queue *sq,
865 			      int qidx)
866 {
867 	u64 head, tail;
868 	struct sk_buff *skb;
869 	struct nicvf *nic = netdev_priv(netdev);
870 	struct sq_hdr_subdesc *hdr;
871 
872 	head = nicvf_queue_reg_read(nic, NIC_QSET_SQ_0_7_HEAD, qidx) >> 4;
873 	tail = nicvf_queue_reg_read(nic, NIC_QSET_SQ_0_7_TAIL, qidx) >> 4;
874 	while (sq->head != head) {
875 		hdr = (struct sq_hdr_subdesc *)GET_SQ_DESC(sq, sq->head);
876 		if (hdr->subdesc_type != SQ_DESC_TYPE_HEADER) {
877 			nicvf_put_sq_desc(sq, 1);
878 			continue;
879 		}
880 		skb = (struct sk_buff *)sq->skbuff[sq->head];
881 		if (skb)
882 			dev_kfree_skb_any(skb);
883 		atomic64_add(1, (atomic64_t *)&netdev->stats.tx_packets);
884 		atomic64_add(hdr->tot_len,
885 			     (atomic64_t *)&netdev->stats.tx_bytes);
886 		nicvf_put_sq_desc(sq, hdr->subdesc_cnt + 1);
887 	}
888 }
889 
890 /* Calculate no of SQ subdescriptors needed to transmit all
891  * segments of this TSO packet.
892  * Taken from 'Tilera network driver' with a minor modification.
893  */
894 static int nicvf_tso_count_subdescs(struct sk_buff *skb)
895 {
896 	struct skb_shared_info *sh = skb_shinfo(skb);
897 	unsigned int sh_len = skb_transport_offset(skb) + tcp_hdrlen(skb);
898 	unsigned int data_len = skb->len - sh_len;
899 	unsigned int p_len = sh->gso_size;
900 	long f_id = -1;    /* id of the current fragment */
901 	long f_size = skb_headlen(skb) - sh_len;  /* current fragment size */
902 	long f_used = 0;  /* bytes used from the current fragment */
903 	long n;            /* size of the current piece of payload */
904 	int num_edescs = 0;
905 	int segment;
906 
907 	for (segment = 0; segment < sh->gso_segs; segment++) {
908 		unsigned int p_used = 0;
909 
910 		/* One edesc for header and for each piece of the payload. */
911 		for (num_edescs++; p_used < p_len; num_edescs++) {
912 			/* Advance as needed. */
913 			while (f_used >= f_size) {
914 				f_id++;
915 				f_size = skb_frag_size(&sh->frags[f_id]);
916 				f_used = 0;
917 			}
918 
919 			/* Use bytes from the current fragment. */
920 			n = p_len - p_used;
921 			if (n > f_size - f_used)
922 				n = f_size - f_used;
923 			f_used += n;
924 			p_used += n;
925 		}
926 
927 		/* The last segment may be less than gso_size. */
928 		data_len -= p_len;
929 		if (data_len < p_len)
930 			p_len = data_len;
931 	}
932 
933 	/* '+ gso_segs' for SQ_HDR_SUDESCs for each segment */
934 	return num_edescs + sh->gso_segs;
935 }
936 
937 /* Get the number of SQ descriptors needed to xmit this skb */
938 static int nicvf_sq_subdesc_required(struct nicvf *nic, struct sk_buff *skb)
939 {
940 	int subdesc_cnt = MIN_SQ_DESC_PER_PKT_XMIT;
941 
942 	if (skb_shinfo(skb)->gso_size && !nic->hw_tso) {
943 		subdesc_cnt = nicvf_tso_count_subdescs(skb);
944 		return subdesc_cnt;
945 	}
946 
947 	if (skb_shinfo(skb)->nr_frags)
948 		subdesc_cnt += skb_shinfo(skb)->nr_frags;
949 
950 	return subdesc_cnt;
951 }
952 
953 /* Add SQ HEADER subdescriptor.
954  * First subdescriptor for every send descriptor.
955  */
956 static inline void
957 nicvf_sq_add_hdr_subdesc(struct nicvf *nic, struct snd_queue *sq, int qentry,
958 			 int subdesc_cnt, struct sk_buff *skb, int len)
959 {
960 	int proto;
961 	struct sq_hdr_subdesc *hdr;
962 
963 	hdr = (struct sq_hdr_subdesc *)GET_SQ_DESC(sq, qentry);
964 	sq->skbuff[qentry] = (u64)skb;
965 
966 	memset(hdr, 0, SND_QUEUE_DESC_SIZE);
967 	hdr->subdesc_type = SQ_DESC_TYPE_HEADER;
968 	/* Enable notification via CQE after processing SQE */
969 	hdr->post_cqe = 1;
970 	/* No of subdescriptors following this */
971 	hdr->subdesc_cnt = subdesc_cnt;
972 	hdr->tot_len = len;
973 
974 	/* Offload checksum calculation to HW */
975 	if (skb->ip_summed == CHECKSUM_PARTIAL) {
976 		hdr->csum_l3 = 1; /* Enable IP csum calculation */
977 		hdr->l3_offset = skb_network_offset(skb);
978 		hdr->l4_offset = skb_transport_offset(skb);
979 
980 		proto = ip_hdr(skb)->protocol;
981 		switch (proto) {
982 		case IPPROTO_TCP:
983 			hdr->csum_l4 = SEND_L4_CSUM_TCP;
984 			break;
985 		case IPPROTO_UDP:
986 			hdr->csum_l4 = SEND_L4_CSUM_UDP;
987 			break;
988 		case IPPROTO_SCTP:
989 			hdr->csum_l4 = SEND_L4_CSUM_SCTP;
990 			break;
991 		}
992 	}
993 
994 	if (nic->hw_tso && skb_shinfo(skb)->gso_size) {
995 		hdr->tso = 1;
996 		hdr->tso_start = skb_transport_offset(skb) + tcp_hdrlen(skb);
997 		hdr->tso_max_paysize = skb_shinfo(skb)->gso_size;
998 		/* For non-tunneled pkts, point this to L2 ethertype */
999 		hdr->inner_l3_offset = skb_network_offset(skb) - 2;
1000 		nic->drv_stats.tx_tso++;
1001 	}
1002 }
1003 
1004 /* SQ GATHER subdescriptor
1005  * Must follow HDR descriptor
1006  */
1007 static inline void nicvf_sq_add_gather_subdesc(struct snd_queue *sq, int qentry,
1008 					       int size, u64 data)
1009 {
1010 	struct sq_gather_subdesc *gather;
1011 
1012 	qentry &= (sq->dmem.q_len - 1);
1013 	gather = (struct sq_gather_subdesc *)GET_SQ_DESC(sq, qentry);
1014 
1015 	memset(gather, 0, SND_QUEUE_DESC_SIZE);
1016 	gather->subdesc_type = SQ_DESC_TYPE_GATHER;
1017 	gather->ld_type = NIC_SEND_LD_TYPE_E_LDD;
1018 	gather->size = size;
1019 	gather->addr = data;
1020 }
1021 
1022 /* Segment a TSO packet into 'gso_size' segments and append
1023  * them to SQ for transfer
1024  */
1025 static int nicvf_sq_append_tso(struct nicvf *nic, struct snd_queue *sq,
1026 			       int sq_num, int qentry, struct sk_buff *skb)
1027 {
1028 	struct tso_t tso;
1029 	int seg_subdescs = 0, desc_cnt = 0;
1030 	int seg_len, total_len, data_left;
1031 	int hdr_qentry = qentry;
1032 	int hdr_len = skb_transport_offset(skb) + tcp_hdrlen(skb);
1033 
1034 	tso_start(skb, &tso);
1035 	total_len = skb->len - hdr_len;
1036 	while (total_len > 0) {
1037 		char *hdr;
1038 
1039 		/* Save Qentry for adding HDR_SUBDESC at the end */
1040 		hdr_qentry = qentry;
1041 
1042 		data_left = min_t(int, skb_shinfo(skb)->gso_size, total_len);
1043 		total_len -= data_left;
1044 
1045 		/* Add segment's header */
1046 		qentry = nicvf_get_nxt_sqentry(sq, qentry);
1047 		hdr = sq->tso_hdrs + qentry * TSO_HEADER_SIZE;
1048 		tso_build_hdr(skb, hdr, &tso, data_left, total_len == 0);
1049 		nicvf_sq_add_gather_subdesc(sq, qentry, hdr_len,
1050 					    sq->tso_hdrs_phys +
1051 					    qentry * TSO_HEADER_SIZE);
1052 		/* HDR_SUDESC + GATHER */
1053 		seg_subdescs = 2;
1054 		seg_len = hdr_len;
1055 
1056 		/* Add segment's payload fragments */
1057 		while (data_left > 0) {
1058 			int size;
1059 
1060 			size = min_t(int, tso.size, data_left);
1061 
1062 			qentry = nicvf_get_nxt_sqentry(sq, qentry);
1063 			nicvf_sq_add_gather_subdesc(sq, qentry, size,
1064 						    virt_to_phys(tso.data));
1065 			seg_subdescs++;
1066 			seg_len += size;
1067 
1068 			data_left -= size;
1069 			tso_build_data(skb, &tso, size);
1070 		}
1071 		nicvf_sq_add_hdr_subdesc(nic, sq, hdr_qentry,
1072 					 seg_subdescs - 1, skb, seg_len);
1073 		sq->skbuff[hdr_qentry] = (u64)NULL;
1074 		qentry = nicvf_get_nxt_sqentry(sq, qentry);
1075 
1076 		desc_cnt += seg_subdescs;
1077 	}
1078 	/* Save SKB in the last segment for freeing */
1079 	sq->skbuff[hdr_qentry] = (u64)skb;
1080 
1081 	/* make sure all memory stores are done before ringing doorbell */
1082 	smp_wmb();
1083 
1084 	/* Inform HW to xmit all TSO segments */
1085 	nicvf_queue_reg_write(nic, NIC_QSET_SQ_0_7_DOOR,
1086 			      sq_num, desc_cnt);
1087 	nic->drv_stats.tx_tso++;
1088 	return 1;
1089 }
1090 
1091 /* Append an skb to a SQ for packet transfer. */
1092 int nicvf_sq_append_skb(struct nicvf *nic, struct sk_buff *skb)
1093 {
1094 	int i, size;
1095 	int subdesc_cnt;
1096 	int sq_num, qentry;
1097 	struct queue_set *qs;
1098 	struct snd_queue *sq;
1099 
1100 	sq_num = skb_get_queue_mapping(skb);
1101 	if (sq_num >= MAX_SND_QUEUES_PER_QS) {
1102 		/* Get secondary Qset's SQ structure */
1103 		i = sq_num / MAX_SND_QUEUES_PER_QS;
1104 		if (!nic->snicvf[i - 1]) {
1105 			netdev_warn(nic->netdev,
1106 				    "Secondary Qset#%d's ptr not initialized\n",
1107 				    i - 1);
1108 			return 1;
1109 		}
1110 		nic = (struct nicvf *)nic->snicvf[i - 1];
1111 		sq_num = sq_num % MAX_SND_QUEUES_PER_QS;
1112 	}
1113 
1114 	qs = nic->qs;
1115 	sq = &qs->sq[sq_num];
1116 
1117 	subdesc_cnt = nicvf_sq_subdesc_required(nic, skb);
1118 	if (subdesc_cnt > atomic_read(&sq->free_cnt))
1119 		goto append_fail;
1120 
1121 	qentry = nicvf_get_sq_desc(sq, subdesc_cnt);
1122 
1123 	/* Check if its a TSO packet */
1124 	if (skb_shinfo(skb)->gso_size && !nic->hw_tso)
1125 		return nicvf_sq_append_tso(nic, sq, sq_num, qentry, skb);
1126 
1127 	/* Add SQ header subdesc */
1128 	nicvf_sq_add_hdr_subdesc(nic, sq, qentry, subdesc_cnt - 1,
1129 				 skb, skb->len);
1130 
1131 	/* Add SQ gather subdescs */
1132 	qentry = nicvf_get_nxt_sqentry(sq, qentry);
1133 	size = skb_is_nonlinear(skb) ? skb_headlen(skb) : skb->len;
1134 	nicvf_sq_add_gather_subdesc(sq, qentry, size, virt_to_phys(skb->data));
1135 
1136 	/* Check for scattered buffer */
1137 	if (!skb_is_nonlinear(skb))
1138 		goto doorbell;
1139 
1140 	for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) {
1141 		const struct skb_frag_struct *frag;
1142 
1143 		frag = &skb_shinfo(skb)->frags[i];
1144 
1145 		qentry = nicvf_get_nxt_sqentry(sq, qentry);
1146 		size = skb_frag_size(frag);
1147 		nicvf_sq_add_gather_subdesc(sq, qentry, size,
1148 					    virt_to_phys(
1149 					    skb_frag_address(frag)));
1150 	}
1151 
1152 doorbell:
1153 	/* make sure all memory stores are done before ringing doorbell */
1154 	smp_wmb();
1155 
1156 	/* Inform HW to xmit new packet */
1157 	nicvf_queue_reg_write(nic, NIC_QSET_SQ_0_7_DOOR,
1158 			      sq_num, subdesc_cnt);
1159 	return 1;
1160 
1161 append_fail:
1162 	/* Use original PCI dev for debug log */
1163 	nic = nic->pnicvf;
1164 	netdev_dbg(nic->netdev, "Not enough SQ descriptors to xmit pkt\n");
1165 	return 0;
1166 }
1167 
1168 static inline unsigned frag_num(unsigned i)
1169 {
1170 #ifdef __BIG_ENDIAN
1171 	return (i & ~3) + 3 - (i & 3);
1172 #else
1173 	return i;
1174 #endif
1175 }
1176 
1177 /* Returns SKB for a received packet */
1178 struct sk_buff *nicvf_get_rcv_skb(struct nicvf *nic, struct cqe_rx_t *cqe_rx)
1179 {
1180 	int frag;
1181 	int payload_len = 0;
1182 	struct sk_buff *skb = NULL;
1183 	struct sk_buff *skb_frag = NULL;
1184 	struct sk_buff *prev_frag = NULL;
1185 	u16 *rb_lens = NULL;
1186 	u64 *rb_ptrs = NULL;
1187 
1188 	rb_lens = (void *)cqe_rx + (3 * sizeof(u64));
1189 	rb_ptrs = (void *)cqe_rx + (6 * sizeof(u64));
1190 
1191 	netdev_dbg(nic->netdev, "%s rb_cnt %d rb0_ptr %llx rb0_sz %d\n",
1192 		   __func__, cqe_rx->rb_cnt, cqe_rx->rb0_ptr, cqe_rx->rb0_sz);
1193 
1194 	for (frag = 0; frag < cqe_rx->rb_cnt; frag++) {
1195 		payload_len = rb_lens[frag_num(frag)];
1196 		if (!frag) {
1197 			/* First fragment */
1198 			skb = nicvf_rb_ptr_to_skb(nic,
1199 						  *rb_ptrs - cqe_rx->align_pad,
1200 						  payload_len);
1201 			if (!skb)
1202 				return NULL;
1203 			skb_reserve(skb, cqe_rx->align_pad);
1204 			skb_put(skb, payload_len);
1205 		} else {
1206 			/* Add fragments */
1207 			skb_frag = nicvf_rb_ptr_to_skb(nic, *rb_ptrs,
1208 						       payload_len);
1209 			if (!skb_frag) {
1210 				dev_kfree_skb(skb);
1211 				return NULL;
1212 			}
1213 
1214 			if (!skb_shinfo(skb)->frag_list)
1215 				skb_shinfo(skb)->frag_list = skb_frag;
1216 			else
1217 				prev_frag->next = skb_frag;
1218 
1219 			prev_frag = skb_frag;
1220 			skb->len += payload_len;
1221 			skb->data_len += payload_len;
1222 			skb_frag->len = payload_len;
1223 		}
1224 		/* Next buffer pointer */
1225 		rb_ptrs++;
1226 	}
1227 	return skb;
1228 }
1229 
1230 static u64 nicvf_int_type_to_mask(int int_type, int q_idx)
1231 {
1232 	u64 reg_val;
1233 
1234 	switch (int_type) {
1235 	case NICVF_INTR_CQ:
1236 		reg_val = ((1ULL << q_idx) << NICVF_INTR_CQ_SHIFT);
1237 		break;
1238 	case NICVF_INTR_SQ:
1239 		reg_val = ((1ULL << q_idx) << NICVF_INTR_SQ_SHIFT);
1240 		break;
1241 	case NICVF_INTR_RBDR:
1242 		reg_val = ((1ULL << q_idx) << NICVF_INTR_RBDR_SHIFT);
1243 		break;
1244 	case NICVF_INTR_PKT_DROP:
1245 		reg_val = (1ULL << NICVF_INTR_PKT_DROP_SHIFT);
1246 		break;
1247 	case NICVF_INTR_TCP_TIMER:
1248 		reg_val = (1ULL << NICVF_INTR_TCP_TIMER_SHIFT);
1249 		break;
1250 	case NICVF_INTR_MBOX:
1251 		reg_val = (1ULL << NICVF_INTR_MBOX_SHIFT);
1252 		break;
1253 	case NICVF_INTR_QS_ERR:
1254 		reg_val = (1ULL << NICVF_INTR_QS_ERR_SHIFT);
1255 		break;
1256 	default:
1257 		reg_val = 0;
1258 	}
1259 
1260 	return reg_val;
1261 }
1262 
1263 /* Enable interrupt */
1264 void nicvf_enable_intr(struct nicvf *nic, int int_type, int q_idx)
1265 {
1266 	u64 mask = nicvf_int_type_to_mask(int_type, q_idx);
1267 
1268 	if (!mask) {
1269 		netdev_dbg(nic->netdev,
1270 			   "Failed to enable interrupt: unknown type\n");
1271 		return;
1272 	}
1273 	nicvf_reg_write(nic, NIC_VF_ENA_W1S,
1274 			nicvf_reg_read(nic, NIC_VF_ENA_W1S) | mask);
1275 }
1276 
1277 /* Disable interrupt */
1278 void nicvf_disable_intr(struct nicvf *nic, int int_type, int q_idx)
1279 {
1280 	u64 mask = nicvf_int_type_to_mask(int_type, q_idx);
1281 
1282 	if (!mask) {
1283 		netdev_dbg(nic->netdev,
1284 			   "Failed to disable interrupt: unknown type\n");
1285 		return;
1286 	}
1287 
1288 	nicvf_reg_write(nic, NIC_VF_ENA_W1C, mask);
1289 }
1290 
1291 /* Clear interrupt */
1292 void nicvf_clear_intr(struct nicvf *nic, int int_type, int q_idx)
1293 {
1294 	u64 mask = nicvf_int_type_to_mask(int_type, q_idx);
1295 
1296 	if (!mask) {
1297 		netdev_dbg(nic->netdev,
1298 			   "Failed to clear interrupt: unknown type\n");
1299 		return;
1300 	}
1301 
1302 	nicvf_reg_write(nic, NIC_VF_INT, mask);
1303 }
1304 
1305 /* Check if interrupt is enabled */
1306 int nicvf_is_intr_enabled(struct nicvf *nic, int int_type, int q_idx)
1307 {
1308 	u64 mask = nicvf_int_type_to_mask(int_type, q_idx);
1309 	/* If interrupt type is unknown, we treat it disabled. */
1310 	if (!mask) {
1311 		netdev_dbg(nic->netdev,
1312 			   "Failed to check interrupt enable: unknown type\n");
1313 		return 0;
1314 	}
1315 
1316 	return mask & nicvf_reg_read(nic, NIC_VF_ENA_W1S);
1317 }
1318 
1319 void nicvf_update_rq_stats(struct nicvf *nic, int rq_idx)
1320 {
1321 	struct rcv_queue *rq;
1322 
1323 #define GET_RQ_STATS(reg) \
1324 	nicvf_reg_read(nic, NIC_QSET_RQ_0_7_STAT_0_1 |\
1325 			    (rq_idx << NIC_Q_NUM_SHIFT) | (reg << 3))
1326 
1327 	rq = &nic->qs->rq[rq_idx];
1328 	rq->stats.bytes = GET_RQ_STATS(RQ_SQ_STATS_OCTS);
1329 	rq->stats.pkts = GET_RQ_STATS(RQ_SQ_STATS_PKTS);
1330 }
1331 
1332 void nicvf_update_sq_stats(struct nicvf *nic, int sq_idx)
1333 {
1334 	struct snd_queue *sq;
1335 
1336 #define GET_SQ_STATS(reg) \
1337 	nicvf_reg_read(nic, NIC_QSET_SQ_0_7_STAT_0_1 |\
1338 			    (sq_idx << NIC_Q_NUM_SHIFT) | (reg << 3))
1339 
1340 	sq = &nic->qs->sq[sq_idx];
1341 	sq->stats.bytes = GET_SQ_STATS(RQ_SQ_STATS_OCTS);
1342 	sq->stats.pkts = GET_SQ_STATS(RQ_SQ_STATS_PKTS);
1343 }
1344 
1345 /* Check for errors in the receive cmp.queue entry */
1346 int nicvf_check_cqe_rx_errs(struct nicvf *nic, struct cqe_rx_t *cqe_rx)
1347 {
1348 	struct nicvf_hw_stats *stats = &nic->hw_stats;
1349 
1350 	if (!cqe_rx->err_level && !cqe_rx->err_opcode)
1351 		return 0;
1352 
1353 	if (netif_msg_rx_err(nic))
1354 		netdev_err(nic->netdev,
1355 			   "%s: RX error CQE err_level 0x%x err_opcode 0x%x\n",
1356 			   nic->netdev->name,
1357 			   cqe_rx->err_level, cqe_rx->err_opcode);
1358 
1359 	switch (cqe_rx->err_opcode) {
1360 	case CQ_RX_ERROP_RE_PARTIAL:
1361 		stats->rx_bgx_truncated_pkts++;
1362 		break;
1363 	case CQ_RX_ERROP_RE_JABBER:
1364 		stats->rx_jabber_errs++;
1365 		break;
1366 	case CQ_RX_ERROP_RE_FCS:
1367 		stats->rx_fcs_errs++;
1368 		break;
1369 	case CQ_RX_ERROP_RE_RX_CTL:
1370 		stats->rx_bgx_errs++;
1371 		break;
1372 	case CQ_RX_ERROP_PREL2_ERR:
1373 		stats->rx_prel2_errs++;
1374 		break;
1375 	case CQ_RX_ERROP_L2_MAL:
1376 		stats->rx_l2_hdr_malformed++;
1377 		break;
1378 	case CQ_RX_ERROP_L2_OVERSIZE:
1379 		stats->rx_oversize++;
1380 		break;
1381 	case CQ_RX_ERROP_L2_UNDERSIZE:
1382 		stats->rx_undersize++;
1383 		break;
1384 	case CQ_RX_ERROP_L2_LENMISM:
1385 		stats->rx_l2_len_mismatch++;
1386 		break;
1387 	case CQ_RX_ERROP_L2_PCLP:
1388 		stats->rx_l2_pclp++;
1389 		break;
1390 	case CQ_RX_ERROP_IP_NOT:
1391 		stats->rx_ip_ver_errs++;
1392 		break;
1393 	case CQ_RX_ERROP_IP_CSUM_ERR:
1394 		stats->rx_ip_csum_errs++;
1395 		break;
1396 	case CQ_RX_ERROP_IP_MAL:
1397 		stats->rx_ip_hdr_malformed++;
1398 		break;
1399 	case CQ_RX_ERROP_IP_MALD:
1400 		stats->rx_ip_payload_malformed++;
1401 		break;
1402 	case CQ_RX_ERROP_IP_HOP:
1403 		stats->rx_ip_ttl_errs++;
1404 		break;
1405 	case CQ_RX_ERROP_L3_PCLP:
1406 		stats->rx_l3_pclp++;
1407 		break;
1408 	case CQ_RX_ERROP_L4_MAL:
1409 		stats->rx_l4_malformed++;
1410 		break;
1411 	case CQ_RX_ERROP_L4_CHK:
1412 		stats->rx_l4_csum_errs++;
1413 		break;
1414 	case CQ_RX_ERROP_UDP_LEN:
1415 		stats->rx_udp_len_errs++;
1416 		break;
1417 	case CQ_RX_ERROP_L4_PORT:
1418 		stats->rx_l4_port_errs++;
1419 		break;
1420 	case CQ_RX_ERROP_TCP_FLAG:
1421 		stats->rx_tcp_flag_errs++;
1422 		break;
1423 	case CQ_RX_ERROP_TCP_OFFSET:
1424 		stats->rx_tcp_offset_errs++;
1425 		break;
1426 	case CQ_RX_ERROP_L4_PCLP:
1427 		stats->rx_l4_pclp++;
1428 		break;
1429 	case CQ_RX_ERROP_RBDR_TRUNC:
1430 		stats->rx_truncated_pkts++;
1431 		break;
1432 	}
1433 
1434 	return 1;
1435 }
1436 
1437 /* Check for errors in the send cmp.queue entry */
1438 int nicvf_check_cqe_tx_errs(struct nicvf *nic,
1439 			    struct cmp_queue *cq, struct cqe_send_t *cqe_tx)
1440 {
1441 	struct cmp_queue_stats *stats = &cq->stats;
1442 
1443 	switch (cqe_tx->send_status) {
1444 	case CQ_TX_ERROP_GOOD:
1445 		stats->tx.good++;
1446 		return 0;
1447 	case CQ_TX_ERROP_DESC_FAULT:
1448 		stats->tx.desc_fault++;
1449 		break;
1450 	case CQ_TX_ERROP_HDR_CONS_ERR:
1451 		stats->tx.hdr_cons_err++;
1452 		break;
1453 	case CQ_TX_ERROP_SUBDC_ERR:
1454 		stats->tx.subdesc_err++;
1455 		break;
1456 	case CQ_TX_ERROP_IMM_SIZE_OFLOW:
1457 		stats->tx.imm_size_oflow++;
1458 		break;
1459 	case CQ_TX_ERROP_DATA_SEQUENCE_ERR:
1460 		stats->tx.data_seq_err++;
1461 		break;
1462 	case CQ_TX_ERROP_MEM_SEQUENCE_ERR:
1463 		stats->tx.mem_seq_err++;
1464 		break;
1465 	case CQ_TX_ERROP_LOCK_VIOL:
1466 		stats->tx.lock_viol++;
1467 		break;
1468 	case CQ_TX_ERROP_DATA_FAULT:
1469 		stats->tx.data_fault++;
1470 		break;
1471 	case CQ_TX_ERROP_TSTMP_CONFLICT:
1472 		stats->tx.tstmp_conflict++;
1473 		break;
1474 	case CQ_TX_ERROP_TSTMP_TIMEOUT:
1475 		stats->tx.tstmp_timeout++;
1476 		break;
1477 	case CQ_TX_ERROP_MEM_FAULT:
1478 		stats->tx.mem_fault++;
1479 		break;
1480 	case CQ_TX_ERROP_CK_OVERLAP:
1481 		stats->tx.csum_overlap++;
1482 		break;
1483 	case CQ_TX_ERROP_CK_OFLOW:
1484 		stats->tx.csum_overflow++;
1485 		break;
1486 	}
1487 
1488 	return 1;
1489 }
1490