1 /**********************************************************************
2  * Author: Cavium, Inc.
3  *
4  * Contact: support@cavium.com
5  *          Please include "LiquidIO" in the subject.
6  *
7  * Copyright (c) 2003-2016 Cavium, Inc.
8  *
9  * This file is free software; you can redistribute it and/or modify
10  * it under the terms of the GNU General Public License, Version 2, as
11  * published by the Free Software Foundation.
12  *
13  * This file is distributed in the hope that it will be useful, but
14  * AS-IS and WITHOUT ANY WARRANTY; without even the implied warranty
15  * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE, TITLE, or
16  * NONINFRINGEMENT.  See the GNU General Public License for more details.
17  ***********************************************************************/
18 #include <linux/pci.h>
19 #include <linux/netdevice.h>
20 #include <linux/vmalloc.h>
21 #include "liquidio_common.h"
22 #include "octeon_droq.h"
23 #include "octeon_iq.h"
24 #include "response_manager.h"
25 #include "octeon_device.h"
26 #include "octeon_main.h"
27 #include "octeon_network.h"
28 #include "cn66xx_regs.h"
29 #include "cn66xx_device.h"
30 #include "cn23xx_pf_device.h"
31 #include "cn23xx_vf_device.h"
32 
33 struct niclist {
34 	struct list_head list;
35 	void *ptr;
36 };
37 
38 struct __dispatch {
39 	struct list_head list;
40 	struct octeon_recv_info *rinfo;
41 	octeon_dispatch_fn_t disp_fn;
42 };
43 
44 /** Get the argument that the user set when registering dispatch
45  *  function for a given opcode/subcode.
46  *  @param  octeon_dev - the octeon device pointer.
47  *  @param  opcode     - the opcode for which the dispatch argument
48  *                       is to be checked.
49  *  @param  subcode    - the subcode for which the dispatch argument
50  *                       is to be checked.
51  *  @return  Success: void * (argument to the dispatch function)
52  *  @return  Failure: NULL
53  *
54  */
55 void *octeon_get_dispatch_arg(struct octeon_device *octeon_dev,
56 			      u16 opcode, u16 subcode)
57 {
58 	int idx;
59 	struct list_head *dispatch;
60 	void *fn_arg = NULL;
61 	u16 combined_opcode = OPCODE_SUBCODE(opcode, subcode);
62 
63 	idx = combined_opcode & OCTEON_OPCODE_MASK;
64 
65 	spin_lock_bh(&octeon_dev->dispatch.lock);
66 
67 	if (octeon_dev->dispatch.count == 0) {
68 		spin_unlock_bh(&octeon_dev->dispatch.lock);
69 		return NULL;
70 	}
71 
72 	if (octeon_dev->dispatch.dlist[idx].opcode == combined_opcode) {
73 		fn_arg = octeon_dev->dispatch.dlist[idx].arg;
74 	} else {
75 		list_for_each(dispatch,
76 			      &octeon_dev->dispatch.dlist[idx].list) {
77 			if (((struct octeon_dispatch *)dispatch)->opcode ==
78 			    combined_opcode) {
79 				fn_arg = ((struct octeon_dispatch *)
80 					  dispatch)->arg;
81 				break;
82 			}
83 		}
84 	}
85 
86 	spin_unlock_bh(&octeon_dev->dispatch.lock);
87 	return fn_arg;
88 }
89 
90 /** Check for packets on Droq. This function should be called with lock held.
91  *  @param  droq - Droq on which count is checked.
92  *  @return Returns packet count.
93  */
94 u32 octeon_droq_check_hw_for_pkts(struct octeon_droq *droq)
95 {
96 	u32 pkt_count = 0;
97 	u32 last_count;
98 
99 	pkt_count = readl(droq->pkts_sent_reg);
100 
101 	last_count = pkt_count - droq->pkt_count;
102 	droq->pkt_count = pkt_count;
103 
104 	/* we shall write to cnts  at napi irq enable or end of droq tasklet */
105 	if (last_count)
106 		atomic_add(last_count, &droq->pkts_pending);
107 
108 	return last_count;
109 }
110 
111 static void octeon_droq_compute_max_packet_bufs(struct octeon_droq *droq)
112 {
113 	u32 count = 0;
114 
115 	/* max_empty_descs is the max. no. of descs that can have no buffers.
116 	 * If the empty desc count goes beyond this value, we cannot safely
117 	 * read in a 64K packet sent by Octeon
118 	 * (64K is max pkt size from Octeon)
119 	 */
120 	droq->max_empty_descs = 0;
121 
122 	do {
123 		droq->max_empty_descs++;
124 		count += droq->buffer_size;
125 	} while (count < (64 * 1024));
126 
127 	droq->max_empty_descs = droq->max_count - droq->max_empty_descs;
128 }
129 
130 static void octeon_droq_reset_indices(struct octeon_droq *droq)
131 {
132 	droq->read_idx = 0;
133 	droq->write_idx = 0;
134 	droq->refill_idx = 0;
135 	droq->refill_count = 0;
136 	atomic_set(&droq->pkts_pending, 0);
137 }
138 
139 static void
140 octeon_droq_destroy_ring_buffers(struct octeon_device *oct,
141 				 struct octeon_droq *droq)
142 {
143 	u32 i;
144 	struct octeon_skb_page_info *pg_info;
145 
146 	for (i = 0; i < droq->max_count; i++) {
147 		pg_info = &droq->recv_buf_list[i].pg_info;
148 		if (!pg_info)
149 			continue;
150 
151 		if (pg_info->dma)
152 			lio_unmap_ring(oct->pci_dev,
153 				       (u64)pg_info->dma);
154 		pg_info->dma = 0;
155 
156 		if (pg_info->page)
157 			recv_buffer_destroy(droq->recv_buf_list[i].buffer,
158 					    pg_info);
159 
160 		droq->recv_buf_list[i].buffer = NULL;
161 	}
162 
163 	octeon_droq_reset_indices(droq);
164 }
165 
166 static int
167 octeon_droq_setup_ring_buffers(struct octeon_device *oct,
168 			       struct octeon_droq *droq)
169 {
170 	u32 i;
171 	void *buf;
172 	struct octeon_droq_desc *desc_ring = droq->desc_ring;
173 
174 	for (i = 0; i < droq->max_count; i++) {
175 		buf = recv_buffer_alloc(oct, &droq->recv_buf_list[i].pg_info);
176 
177 		if (!buf) {
178 			dev_err(&oct->pci_dev->dev, "%s buffer alloc failed\n",
179 				__func__);
180 			droq->stats.rx_alloc_failure++;
181 			return -ENOMEM;
182 		}
183 
184 		droq->recv_buf_list[i].buffer = buf;
185 		droq->recv_buf_list[i].data = get_rbd(buf);
186 		desc_ring[i].info_ptr = 0;
187 		desc_ring[i].buffer_ptr =
188 			lio_map_ring(droq->recv_buf_list[i].buffer);
189 	}
190 
191 	octeon_droq_reset_indices(droq);
192 
193 	octeon_droq_compute_max_packet_bufs(droq);
194 
195 	return 0;
196 }
197 
198 int octeon_delete_droq(struct octeon_device *oct, u32 q_no)
199 {
200 	struct octeon_droq *droq = oct->droq[q_no];
201 
202 	dev_dbg(&oct->pci_dev->dev, "%s[%d]\n", __func__, q_no);
203 
204 	octeon_droq_destroy_ring_buffers(oct, droq);
205 	vfree(droq->recv_buf_list);
206 
207 	if (droq->desc_ring)
208 		lio_dma_free(oct, (droq->max_count * OCT_DROQ_DESC_SIZE),
209 			     droq->desc_ring, droq->desc_ring_dma);
210 
211 	memset(droq, 0, OCT_DROQ_SIZE);
212 	oct->io_qmask.oq &= ~(1ULL << q_no);
213 	vfree(oct->droq[q_no]);
214 	oct->droq[q_no] = NULL;
215 	oct->num_oqs--;
216 
217 	return 0;
218 }
219 
220 int octeon_init_droq(struct octeon_device *oct,
221 		     u32 q_no,
222 		     u32 num_descs,
223 		     u32 desc_size,
224 		     void *app_ctx)
225 {
226 	struct octeon_droq *droq;
227 	u32 desc_ring_size = 0, c_num_descs = 0, c_buf_size = 0;
228 	u32 c_pkts_per_intr = 0, c_refill_threshold = 0;
229 	int numa_node = dev_to_node(&oct->pci_dev->dev);
230 
231 	dev_dbg(&oct->pci_dev->dev, "%s[%d]\n", __func__, q_no);
232 
233 	droq = oct->droq[q_no];
234 	memset(droq, 0, OCT_DROQ_SIZE);
235 
236 	droq->oct_dev = oct;
237 	droq->q_no = q_no;
238 	if (app_ctx)
239 		droq->app_ctx = app_ctx;
240 	else
241 		droq->app_ctx = (void *)(size_t)q_no;
242 
243 	c_num_descs = num_descs;
244 	c_buf_size = desc_size;
245 	if (OCTEON_CN6XXX(oct)) {
246 		struct octeon_config *conf6x = CHIP_CONF(oct, cn6xxx);
247 
248 		c_pkts_per_intr = (u32)CFG_GET_OQ_PKTS_PER_INTR(conf6x);
249 		c_refill_threshold =
250 			(u32)CFG_GET_OQ_REFILL_THRESHOLD(conf6x);
251 	} else if (OCTEON_CN23XX_PF(oct)) {
252 		struct octeon_config *conf23 = CHIP_CONF(oct, cn23xx_pf);
253 
254 		c_pkts_per_intr = (u32)CFG_GET_OQ_PKTS_PER_INTR(conf23);
255 		c_refill_threshold = (u32)CFG_GET_OQ_REFILL_THRESHOLD(conf23);
256 	} else if (OCTEON_CN23XX_VF(oct)) {
257 		struct octeon_config *conf23 = CHIP_CONF(oct, cn23xx_vf);
258 
259 		c_pkts_per_intr = (u32)CFG_GET_OQ_PKTS_PER_INTR(conf23);
260 		c_refill_threshold = (u32)CFG_GET_OQ_REFILL_THRESHOLD(conf23);
261 	} else {
262 		return 1;
263 	}
264 
265 	droq->max_count = c_num_descs;
266 	droq->buffer_size = c_buf_size;
267 
268 	desc_ring_size = droq->max_count * OCT_DROQ_DESC_SIZE;
269 	droq->desc_ring = lio_dma_alloc(oct, desc_ring_size,
270 					(dma_addr_t *)&droq->desc_ring_dma);
271 
272 	if (!droq->desc_ring) {
273 		dev_err(&oct->pci_dev->dev,
274 			"Output queue %d ring alloc failed\n", q_no);
275 		return 1;
276 	}
277 
278 	dev_dbg(&oct->pci_dev->dev, "droq[%d]: desc_ring: virt: 0x%p, dma: %lx\n",
279 		q_no, droq->desc_ring, droq->desc_ring_dma);
280 	dev_dbg(&oct->pci_dev->dev, "droq[%d]: num_desc: %d\n", q_no,
281 		droq->max_count);
282 
283 	droq->recv_buf_list = (struct octeon_recv_buffer *)
284 	      vzalloc_node(array_size(droq->max_count, OCT_DROQ_RECVBUF_SIZE),
285 			   numa_node);
286 	if (!droq->recv_buf_list)
287 		droq->recv_buf_list = (struct octeon_recv_buffer *)
288 		      vzalloc(array_size(droq->max_count,
289 					 OCT_DROQ_RECVBUF_SIZE));
290 	if (!droq->recv_buf_list) {
291 		dev_err(&oct->pci_dev->dev, "Output queue recv buf list alloc failed\n");
292 		goto init_droq_fail;
293 	}
294 
295 	if (octeon_droq_setup_ring_buffers(oct, droq))
296 		goto init_droq_fail;
297 
298 	droq->pkts_per_intr = c_pkts_per_intr;
299 	droq->refill_threshold = c_refill_threshold;
300 
301 	dev_dbg(&oct->pci_dev->dev, "DROQ INIT: max_empty_descs: %d\n",
302 		droq->max_empty_descs);
303 
304 	spin_lock_init(&droq->lock);
305 
306 	INIT_LIST_HEAD(&droq->dispatch_list);
307 
308 	/* For 56xx Pass1, this function won't be called, so no checks. */
309 	oct->fn_list.setup_oq_regs(oct, q_no);
310 
311 	oct->io_qmask.oq |= BIT_ULL(q_no);
312 
313 	return 0;
314 
315 init_droq_fail:
316 	octeon_delete_droq(oct, q_no);
317 	return 1;
318 }
319 
320 /* octeon_create_recv_info
321  * Parameters:
322  *  octeon_dev - pointer to the octeon device structure
323  *  droq       - droq in which the packet arrived.
324  *  buf_cnt    - no. of buffers used by the packet.
325  *  idx        - index in the descriptor for the first buffer in the packet.
326  * Description:
327  *  Allocates a recv_info_t and copies the buffer addresses for packet data
328  *  into the recv_pkt space which starts at an 8B offset from recv_info_t.
329  *  Flags the descriptors for refill later. If available descriptors go
330  *  below the threshold to receive a 64K pkt, new buffers are first allocated
331  *  before the recv_pkt_t is created.
332  *  This routine will be called in interrupt context.
333  * Returns:
334  *  Success: Pointer to recv_info_t
335  *  Failure: NULL.
336  * Locks:
337  *  The droq->lock is held when this routine is called.
338  */
339 static inline struct octeon_recv_info *octeon_create_recv_info(
340 		struct octeon_device *octeon_dev,
341 		struct octeon_droq *droq,
342 		u32 buf_cnt,
343 		u32 idx)
344 {
345 	struct octeon_droq_info *info;
346 	struct octeon_recv_pkt *recv_pkt;
347 	struct octeon_recv_info *recv_info;
348 	u32 i, bytes_left;
349 	struct octeon_skb_page_info *pg_info;
350 
351 	info = (struct octeon_droq_info *)droq->recv_buf_list[idx].data;
352 
353 	recv_info = octeon_alloc_recv_info(sizeof(struct __dispatch));
354 	if (!recv_info)
355 		return NULL;
356 
357 	recv_pkt = recv_info->recv_pkt;
358 	recv_pkt->rh = info->rh;
359 	recv_pkt->length = (u32)info->length;
360 	recv_pkt->buffer_count = (u16)buf_cnt;
361 	recv_pkt->octeon_id = (u16)octeon_dev->octeon_id;
362 
363 	i = 0;
364 	bytes_left = (u32)info->length;
365 
366 	while (buf_cnt) {
367 		{
368 			pg_info = &droq->recv_buf_list[idx].pg_info;
369 
370 			lio_unmap_ring(octeon_dev->pci_dev,
371 				       (u64)pg_info->dma);
372 			pg_info->page = NULL;
373 			pg_info->dma = 0;
374 		}
375 
376 		recv_pkt->buffer_size[i] =
377 			(bytes_left >=
378 			 droq->buffer_size) ? droq->buffer_size : bytes_left;
379 
380 		recv_pkt->buffer_ptr[i] = droq->recv_buf_list[idx].buffer;
381 		droq->recv_buf_list[idx].buffer = NULL;
382 
383 		idx = incr_index(idx, 1, droq->max_count);
384 		bytes_left -= droq->buffer_size;
385 		i++;
386 		buf_cnt--;
387 	}
388 
389 	return recv_info;
390 }
391 
392 /* If we were not able to refill all buffers, try to move around
393  * the buffers that were not dispatched.
394  */
395 static inline u32
396 octeon_droq_refill_pullup_descs(struct octeon_droq *droq,
397 				struct octeon_droq_desc *desc_ring)
398 {
399 	u32 desc_refilled = 0;
400 
401 	u32 refill_index = droq->refill_idx;
402 
403 	while (refill_index != droq->read_idx) {
404 		if (droq->recv_buf_list[refill_index].buffer) {
405 			droq->recv_buf_list[droq->refill_idx].buffer =
406 				droq->recv_buf_list[refill_index].buffer;
407 			droq->recv_buf_list[droq->refill_idx].data =
408 				droq->recv_buf_list[refill_index].data;
409 			desc_ring[droq->refill_idx].buffer_ptr =
410 				desc_ring[refill_index].buffer_ptr;
411 			droq->recv_buf_list[refill_index].buffer = NULL;
412 			desc_ring[refill_index].buffer_ptr = 0;
413 			do {
414 				droq->refill_idx = incr_index(droq->refill_idx,
415 							      1,
416 							      droq->max_count);
417 				desc_refilled++;
418 				droq->refill_count--;
419 			} while (droq->recv_buf_list[droq->refill_idx].buffer);
420 		}
421 		refill_index = incr_index(refill_index, 1, droq->max_count);
422 	}                       /* while */
423 	return desc_refilled;
424 }
425 
426 /* octeon_droq_refill
427  * Parameters:
428  *  droq       - droq in which descriptors require new buffers.
429  * Description:
430  *  Called during normal DROQ processing in interrupt mode or by the poll
431  *  thread to refill the descriptors from which buffers were dispatched
432  *  to upper layers. Attempts to allocate new buffers. If that fails, moves
433  *  up buffers (that were not dispatched) to form a contiguous ring.
434  * Returns:
435  *  No of descriptors refilled.
436  * Locks:
437  *  This routine is called with droq->lock held.
438  */
439 static u32
440 octeon_droq_refill(struct octeon_device *octeon_dev, struct octeon_droq *droq)
441 {
442 	struct octeon_droq_desc *desc_ring;
443 	void *buf = NULL;
444 	u8 *data;
445 	u32 desc_refilled = 0;
446 	struct octeon_skb_page_info *pg_info;
447 
448 	desc_ring = droq->desc_ring;
449 
450 	while (droq->refill_count && (desc_refilled < droq->max_count)) {
451 		/* If a valid buffer exists (happens if there is no dispatch),
452 		 * reuse
453 		 * the buffer, else allocate.
454 		 */
455 		if (!droq->recv_buf_list[droq->refill_idx].buffer) {
456 			pg_info =
457 				&droq->recv_buf_list[droq->refill_idx].pg_info;
458 			/* Either recycle the existing pages or go for
459 			 * new page alloc
460 			 */
461 			if (pg_info->page)
462 				buf = recv_buffer_reuse(octeon_dev, pg_info);
463 			else
464 				buf = recv_buffer_alloc(octeon_dev, pg_info);
465 			/* If a buffer could not be allocated, no point in
466 			 * continuing
467 			 */
468 			if (!buf) {
469 				droq->stats.rx_alloc_failure++;
470 				break;
471 			}
472 			droq->recv_buf_list[droq->refill_idx].buffer =
473 				buf;
474 			data = get_rbd(buf);
475 		} else {
476 			data = get_rbd(droq->recv_buf_list
477 				       [droq->refill_idx].buffer);
478 		}
479 
480 		droq->recv_buf_list[droq->refill_idx].data = data;
481 
482 		desc_ring[droq->refill_idx].buffer_ptr =
483 			lio_map_ring(droq->recv_buf_list[
484 				     droq->refill_idx].buffer);
485 
486 		droq->refill_idx = incr_index(droq->refill_idx, 1,
487 					      droq->max_count);
488 		desc_refilled++;
489 		droq->refill_count--;
490 	}
491 
492 	if (droq->refill_count)
493 		desc_refilled +=
494 			octeon_droq_refill_pullup_descs(droq, desc_ring);
495 
496 	/* if droq->refill_count
497 	 * The refill count would not change in pass two. We only moved buffers
498 	 * to close the gap in the ring, but we would still have the same no. of
499 	 * buffers to refill.
500 	 */
501 	return desc_refilled;
502 }
503 
504 /** check if we can allocate packets to get out of oom.
505  *  @param  droq - Droq being checked.
506  *  @return does not return anything
507  */
508 void octeon_droq_check_oom(struct octeon_droq *droq)
509 {
510 	int desc_refilled;
511 	struct octeon_device *oct = droq->oct_dev;
512 
513 	if (readl(droq->pkts_credit_reg) <= CN23XX_SLI_DEF_BP) {
514 		spin_lock_bh(&droq->lock);
515 		desc_refilled = octeon_droq_refill(oct, droq);
516 		if (desc_refilled) {
517 			/* Flush the droq descriptor data to memory to be sure
518 			 * that when we update the credits the data in memory
519 			 * is accurate.
520 			 */
521 			wmb();
522 			writel(desc_refilled, droq->pkts_credit_reg);
523 			/* make sure mmio write completes */
524 			mmiowb();
525 		}
526 		spin_unlock_bh(&droq->lock);
527 	}
528 }
529 
530 static inline u32
531 octeon_droq_get_bufcount(u32 buf_size, u32 total_len)
532 {
533 	return ((total_len + buf_size - 1) / buf_size);
534 }
535 
536 static int
537 octeon_droq_dispatch_pkt(struct octeon_device *oct,
538 			 struct octeon_droq *droq,
539 			 union octeon_rh *rh,
540 			 struct octeon_droq_info *info)
541 {
542 	u32 cnt;
543 	octeon_dispatch_fn_t disp_fn;
544 	struct octeon_recv_info *rinfo;
545 
546 	cnt = octeon_droq_get_bufcount(droq->buffer_size, (u32)info->length);
547 
548 	disp_fn = octeon_get_dispatch(oct, (u16)rh->r.opcode,
549 				      (u16)rh->r.subcode);
550 	if (disp_fn) {
551 		rinfo = octeon_create_recv_info(oct, droq, cnt, droq->read_idx);
552 		if (rinfo) {
553 			struct __dispatch *rdisp = rinfo->rsvd;
554 
555 			rdisp->rinfo = rinfo;
556 			rdisp->disp_fn = disp_fn;
557 			rinfo->recv_pkt->rh = *rh;
558 			list_add_tail(&rdisp->list,
559 				      &droq->dispatch_list);
560 		} else {
561 			droq->stats.dropped_nomem++;
562 		}
563 	} else {
564 		dev_err(&oct->pci_dev->dev, "DROQ: No dispatch function (opcode %u/%u)\n",
565 			(unsigned int)rh->r.opcode,
566 			(unsigned int)rh->r.subcode);
567 		droq->stats.dropped_nodispatch++;
568 	}
569 
570 	return cnt;
571 }
572 
573 static inline void octeon_droq_drop_packets(struct octeon_device *oct,
574 					    struct octeon_droq *droq,
575 					    u32 cnt)
576 {
577 	u32 i = 0, buf_cnt;
578 	struct octeon_droq_info *info;
579 
580 	for (i = 0; i < cnt; i++) {
581 		info = (struct octeon_droq_info *)
582 			droq->recv_buf_list[droq->read_idx].data;
583 		octeon_swap_8B_data((u64 *)info, 2);
584 
585 		if (info->length) {
586 			info->length += OCTNET_FRM_LENGTH_SIZE;
587 			droq->stats.bytes_received += info->length;
588 			buf_cnt = octeon_droq_get_bufcount(droq->buffer_size,
589 							   (u32)info->length);
590 		} else {
591 			dev_err(&oct->pci_dev->dev, "DROQ: In drop: pkt with len 0\n");
592 			buf_cnt = 1;
593 		}
594 
595 		droq->read_idx = incr_index(droq->read_idx, buf_cnt,
596 					    droq->max_count);
597 		droq->refill_count += buf_cnt;
598 	}
599 }
600 
601 static u32
602 octeon_droq_fast_process_packets(struct octeon_device *oct,
603 				 struct octeon_droq *droq,
604 				 u32 pkts_to_process)
605 {
606 	struct octeon_droq_info *info;
607 	union octeon_rh *rh;
608 	u32 pkt, total_len = 0, pkt_count;
609 
610 	pkt_count = pkts_to_process;
611 
612 	for (pkt = 0; pkt < pkt_count; pkt++) {
613 		u32 pkt_len = 0;
614 		struct sk_buff *nicbuf = NULL;
615 		struct octeon_skb_page_info *pg_info;
616 		void *buf;
617 
618 		info = (struct octeon_droq_info *)
619 			droq->recv_buf_list[droq->read_idx].data;
620 		octeon_swap_8B_data((u64 *)info, 2);
621 
622 		if (!info->length) {
623 			dev_err(&oct->pci_dev->dev,
624 				"DROQ[%d] idx: %d len:0, pkt_cnt: %d\n",
625 				droq->q_no, droq->read_idx, pkt_count);
626 			print_hex_dump_bytes("", DUMP_PREFIX_ADDRESS,
627 					     (u8 *)info,
628 					     OCT_DROQ_INFO_SIZE);
629 			break;
630 		}
631 
632 		/* Len of resp hdr in included in the received data len. */
633 		rh = &info->rh;
634 
635 		info->length += OCTNET_FRM_LENGTH_SIZE;
636 		rh->r_dh.len += (ROUNDUP8(OCT_DROQ_INFO_SIZE) / sizeof(u64));
637 		total_len += (u32)info->length;
638 		if (opcode_slow_path(rh)) {
639 			u32 buf_cnt;
640 
641 			buf_cnt = octeon_droq_dispatch_pkt(oct, droq, rh, info);
642 			droq->read_idx = incr_index(droq->read_idx,
643 						    buf_cnt, droq->max_count);
644 			droq->refill_count += buf_cnt;
645 		} else {
646 			if (info->length <= droq->buffer_size) {
647 				pkt_len = (u32)info->length;
648 				nicbuf = droq->recv_buf_list[
649 					droq->read_idx].buffer;
650 				pg_info = &droq->recv_buf_list[
651 					droq->read_idx].pg_info;
652 				if (recv_buffer_recycle(oct, pg_info))
653 					pg_info->page = NULL;
654 				droq->recv_buf_list[droq->read_idx].buffer =
655 					NULL;
656 
657 				droq->read_idx = incr_index(droq->read_idx, 1,
658 							    droq->max_count);
659 				droq->refill_count++;
660 			} else {
661 				nicbuf = octeon_fast_packet_alloc((u32)
662 								  info->length);
663 				pkt_len = 0;
664 				/* nicbuf allocation can fail. We'll handle it
665 				 * inside the loop.
666 				 */
667 				while (pkt_len < info->length) {
668 					int cpy_len, idx = droq->read_idx;
669 
670 					cpy_len = ((pkt_len + droq->buffer_size)
671 						   > info->length) ?
672 						((u32)info->length - pkt_len) :
673 						droq->buffer_size;
674 
675 					if (nicbuf) {
676 						octeon_fast_packet_next(droq,
677 									nicbuf,
678 									cpy_len,
679 									idx);
680 						buf = droq->recv_buf_list[
681 							idx].buffer;
682 						recv_buffer_fast_free(buf);
683 						droq->recv_buf_list[idx].buffer
684 							= NULL;
685 					} else {
686 						droq->stats.rx_alloc_failure++;
687 					}
688 
689 					pkt_len += cpy_len;
690 					droq->read_idx =
691 						incr_index(droq->read_idx, 1,
692 							   droq->max_count);
693 					droq->refill_count++;
694 				}
695 			}
696 
697 			if (nicbuf) {
698 				if (droq->ops.fptr) {
699 					droq->ops.fptr(oct->octeon_id,
700 						       nicbuf, pkt_len,
701 						       rh, &droq->napi,
702 						       droq->ops.farg);
703 				} else {
704 					recv_buffer_free(nicbuf);
705 				}
706 			}
707 		}
708 
709 		if (droq->refill_count >= droq->refill_threshold) {
710 			int desc_refilled = octeon_droq_refill(oct, droq);
711 
712 			/* Flush the droq descriptor data to memory to be sure
713 			 * that when we update the credits the data in memory
714 			 * is accurate.
715 			 */
716 			wmb();
717 			writel((desc_refilled), droq->pkts_credit_reg);
718 			/* make sure mmio write completes */
719 			mmiowb();
720 		}
721 
722 	}                       /* for (each packet)... */
723 
724 	/* Increment refill_count by the number of buffers processed. */
725 	droq->stats.pkts_received += pkt;
726 	droq->stats.bytes_received += total_len;
727 
728 	if ((droq->ops.drop_on_max) && (pkts_to_process - pkt)) {
729 		octeon_droq_drop_packets(oct, droq, (pkts_to_process - pkt));
730 
731 		droq->stats.dropped_toomany += (pkts_to_process - pkt);
732 		return pkts_to_process;
733 	}
734 
735 	return pkt;
736 }
737 
738 int
739 octeon_droq_process_packets(struct octeon_device *oct,
740 			    struct octeon_droq *droq,
741 			    u32 budget)
742 {
743 	u32 pkt_count = 0, pkts_processed = 0;
744 	struct list_head *tmp, *tmp2;
745 
746 	/* Grab the droq lock */
747 	spin_lock(&droq->lock);
748 
749 	octeon_droq_check_hw_for_pkts(droq);
750 	pkt_count = atomic_read(&droq->pkts_pending);
751 
752 	if (!pkt_count) {
753 		spin_unlock(&droq->lock);
754 		return 0;
755 	}
756 
757 	if (pkt_count > budget)
758 		pkt_count = budget;
759 
760 	pkts_processed = octeon_droq_fast_process_packets(oct, droq, pkt_count);
761 
762 	atomic_sub(pkts_processed, &droq->pkts_pending);
763 
764 	/* Release the spin lock */
765 	spin_unlock(&droq->lock);
766 
767 	list_for_each_safe(tmp, tmp2, &droq->dispatch_list) {
768 		struct __dispatch *rdisp = (struct __dispatch *)tmp;
769 
770 		list_del(tmp);
771 		rdisp->disp_fn(rdisp->rinfo,
772 			       octeon_get_dispatch_arg
773 			       (oct,
774 				(u16)rdisp->rinfo->recv_pkt->rh.r.opcode,
775 				(u16)rdisp->rinfo->recv_pkt->rh.r.subcode));
776 	}
777 
778 	/* If there are packets pending. schedule tasklet again */
779 	if (atomic_read(&droq->pkts_pending))
780 		return 1;
781 
782 	return 0;
783 }
784 
785 /**
786  * Utility function to poll for packets. check_hw_for_packets must be
787  * called before calling this routine.
788  */
789 
790 int
791 octeon_droq_process_poll_pkts(struct octeon_device *oct,
792 			      struct octeon_droq *droq, u32 budget)
793 {
794 	struct list_head *tmp, *tmp2;
795 	u32 pkts_available = 0, pkts_processed = 0;
796 	u32 total_pkts_processed = 0;
797 
798 	if (budget > droq->max_count)
799 		budget = droq->max_count;
800 
801 	spin_lock(&droq->lock);
802 
803 	while (total_pkts_processed < budget) {
804 		octeon_droq_check_hw_for_pkts(droq);
805 
806 		pkts_available = min((budget - total_pkts_processed),
807 				     (u32)(atomic_read(&droq->pkts_pending)));
808 
809 		if (pkts_available == 0)
810 			break;
811 
812 		pkts_processed =
813 			octeon_droq_fast_process_packets(oct, droq,
814 							 pkts_available);
815 
816 		atomic_sub(pkts_processed, &droq->pkts_pending);
817 
818 		total_pkts_processed += pkts_processed;
819 	}
820 
821 	spin_unlock(&droq->lock);
822 
823 	list_for_each_safe(tmp, tmp2, &droq->dispatch_list) {
824 		struct __dispatch *rdisp = (struct __dispatch *)tmp;
825 
826 		list_del(tmp);
827 		rdisp->disp_fn(rdisp->rinfo,
828 			       octeon_get_dispatch_arg
829 			       (oct,
830 				(u16)rdisp->rinfo->recv_pkt->rh.r.opcode,
831 				(u16)rdisp->rinfo->recv_pkt->rh.r.subcode));
832 	}
833 
834 	return total_pkts_processed;
835 }
836 
837 /* Enable Pkt Interrupt */
838 int
839 octeon_enable_irq(struct octeon_device *oct, u32 q_no)
840 {
841 	switch (oct->chip_id) {
842 	case OCTEON_CN66XX:
843 	case OCTEON_CN68XX: {
844 		struct octeon_cn6xxx *cn6xxx =
845 			(struct octeon_cn6xxx *)oct->chip;
846 		unsigned long flags;
847 		u32 value;
848 
849 		spin_lock_irqsave
850 			(&cn6xxx->lock_for_droq_int_enb_reg, flags);
851 		value = octeon_read_csr(oct, CN6XXX_SLI_PKT_TIME_INT_ENB);
852 		value |= (1 << q_no);
853 		octeon_write_csr(oct, CN6XXX_SLI_PKT_TIME_INT_ENB, value);
854 		value = octeon_read_csr(oct, CN6XXX_SLI_PKT_CNT_INT_ENB);
855 		value |= (1 << q_no);
856 		octeon_write_csr(oct, CN6XXX_SLI_PKT_CNT_INT_ENB, value);
857 
858 		/* don't bother flushing the enables */
859 
860 		spin_unlock_irqrestore
861 			(&cn6xxx->lock_for_droq_int_enb_reg, flags);
862 	}
863 		break;
864 	case OCTEON_CN23XX_PF_VID:
865 		lio_enable_irq(oct->droq[q_no], oct->instr_queue[q_no]);
866 		break;
867 
868 	case OCTEON_CN23XX_VF_VID:
869 		lio_enable_irq(oct->droq[q_no], oct->instr_queue[q_no]);
870 		break;
871 	default:
872 		dev_err(&oct->pci_dev->dev, "%s Unknown Chip\n", __func__);
873 		return 1;
874 	}
875 
876 	return 0;
877 }
878 
879 int octeon_register_droq_ops(struct octeon_device *oct, u32 q_no,
880 			     struct octeon_droq_ops *ops)
881 {
882 	struct octeon_droq *droq;
883 	unsigned long flags;
884 	struct octeon_config *oct_cfg = NULL;
885 
886 	oct_cfg = octeon_get_conf(oct);
887 
888 	if (!oct_cfg)
889 		return -EINVAL;
890 
891 	if (!(ops)) {
892 		dev_err(&oct->pci_dev->dev, "%s: droq_ops pointer is NULL\n",
893 			__func__);
894 		return -EINVAL;
895 	}
896 
897 	if (q_no >= CFG_GET_OQ_MAX_Q(oct_cfg)) {
898 		dev_err(&oct->pci_dev->dev, "%s: droq id (%d) exceeds MAX (%d)\n",
899 			__func__, q_no, (oct->num_oqs - 1));
900 		return -EINVAL;
901 	}
902 
903 	droq = oct->droq[q_no];
904 
905 	spin_lock_irqsave(&droq->lock, flags);
906 
907 	memcpy(&droq->ops, ops, sizeof(struct octeon_droq_ops));
908 
909 	spin_unlock_irqrestore(&droq->lock, flags);
910 
911 	return 0;
912 }
913 
914 int octeon_unregister_droq_ops(struct octeon_device *oct, u32 q_no)
915 {
916 	unsigned long flags;
917 	struct octeon_droq *droq;
918 	struct octeon_config *oct_cfg = NULL;
919 
920 	oct_cfg = octeon_get_conf(oct);
921 
922 	if (!oct_cfg)
923 		return -EINVAL;
924 
925 	if (q_no >= CFG_GET_OQ_MAX_Q(oct_cfg)) {
926 		dev_err(&oct->pci_dev->dev, "%s: droq id (%d) exceeds MAX (%d)\n",
927 			__func__, q_no, oct->num_oqs - 1);
928 		return -EINVAL;
929 	}
930 
931 	droq = oct->droq[q_no];
932 
933 	if (!droq) {
934 		dev_info(&oct->pci_dev->dev,
935 			 "Droq id (%d) not available.\n", q_no);
936 		return 0;
937 	}
938 
939 	spin_lock_irqsave(&droq->lock, flags);
940 
941 	droq->ops.fptr = NULL;
942 	droq->ops.farg = NULL;
943 	droq->ops.drop_on_max = 0;
944 
945 	spin_unlock_irqrestore(&droq->lock, flags);
946 
947 	return 0;
948 }
949 
950 int octeon_create_droq(struct octeon_device *oct,
951 		       u32 q_no, u32 num_descs,
952 		       u32 desc_size, void *app_ctx)
953 {
954 	struct octeon_droq *droq;
955 	int numa_node = dev_to_node(&oct->pci_dev->dev);
956 
957 	if (oct->droq[q_no]) {
958 		dev_dbg(&oct->pci_dev->dev, "Droq already in use. Cannot create droq %d again\n",
959 			q_no);
960 		return 1;
961 	}
962 
963 	/* Allocate the DS for the new droq. */
964 	droq = vmalloc_node(sizeof(*droq), numa_node);
965 	if (!droq)
966 		droq = vmalloc(sizeof(*droq));
967 	if (!droq)
968 		return -1;
969 
970 	memset(droq, 0, sizeof(struct octeon_droq));
971 
972 	/*Disable the pkt o/p for this Q  */
973 	octeon_set_droq_pkt_op(oct, q_no, 0);
974 	oct->droq[q_no] = droq;
975 
976 	/* Initialize the Droq */
977 	if (octeon_init_droq(oct, q_no, num_descs, desc_size, app_ctx)) {
978 		vfree(oct->droq[q_no]);
979 		oct->droq[q_no] = NULL;
980 		return -1;
981 	}
982 
983 	oct->num_oqs++;
984 
985 	dev_dbg(&oct->pci_dev->dev, "%s: Total number of OQ: %d\n", __func__,
986 		oct->num_oqs);
987 
988 	/* Global Droq register settings */
989 
990 	/* As of now not required, as setting are done for all 32 Droqs at
991 	 * the same time.
992 	 */
993 	return 0;
994 }
995