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 static inline 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 
149 		if (pg_info->dma)
150 			lio_unmap_ring(oct->pci_dev,
151 				       (u64)pg_info->dma);
152 		pg_info->dma = 0;
153 
154 		if (pg_info->page)
155 			recv_buffer_destroy(droq->recv_buf_list[i].buffer,
156 					    pg_info);
157 
158 		droq->recv_buf_list[i].buffer = NULL;
159 	}
160 
161 	octeon_droq_reset_indices(droq);
162 }
163 
164 static int
165 octeon_droq_setup_ring_buffers(struct octeon_device *oct,
166 			       struct octeon_droq *droq)
167 {
168 	u32 i;
169 	void *buf;
170 	struct octeon_droq_desc *desc_ring = droq->desc_ring;
171 
172 	for (i = 0; i < droq->max_count; i++) {
173 		buf = recv_buffer_alloc(oct, &droq->recv_buf_list[i].pg_info);
174 
175 		if (!buf) {
176 			dev_err(&oct->pci_dev->dev, "%s buffer alloc failed\n",
177 				__func__);
178 			droq->stats.rx_alloc_failure++;
179 			return -ENOMEM;
180 		}
181 
182 		droq->recv_buf_list[i].buffer = buf;
183 		droq->recv_buf_list[i].data = get_rbd(buf);
184 		droq->info_list[i].length = 0;
185 
186 		/* map ring buffers into memory */
187 		desc_ring[i].info_ptr = lio_map_ring_info(droq, i);
188 		desc_ring[i].buffer_ptr =
189 			lio_map_ring(droq->recv_buf_list[i].buffer);
190 	}
191 
192 	octeon_droq_reset_indices(droq);
193 
194 	octeon_droq_compute_max_packet_bufs(droq);
195 
196 	return 0;
197 }
198 
199 int octeon_delete_droq(struct octeon_device *oct, u32 q_no)
200 {
201 	struct octeon_droq *droq = oct->droq[q_no];
202 
203 	dev_dbg(&oct->pci_dev->dev, "%s[%d]\n", __func__, q_no);
204 
205 	octeon_droq_destroy_ring_buffers(oct, droq);
206 	vfree(droq->recv_buf_list);
207 
208 	if (droq->info_base_addr)
209 		lio_free_info_buffer(oct, droq);
210 
211 	if (droq->desc_ring)
212 		lio_dma_free(oct, (droq->max_count * OCT_DROQ_DESC_SIZE),
213 			     droq->desc_ring, droq->desc_ring_dma);
214 
215 	memset(droq, 0, OCT_DROQ_SIZE);
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->info_list = lio_alloc_info_buffer(oct, droq);
284 	if (!droq->info_list) {
285 		dev_err(&oct->pci_dev->dev, "Cannot allocate memory for info list.\n");
286 		lio_dma_free(oct, (droq->max_count * OCT_DROQ_DESC_SIZE),
287 			     droq->desc_ring, droq->desc_ring_dma);
288 		return 1;
289 	}
290 
291 	droq->recv_buf_list = (struct octeon_recv_buffer *)
292 			      vmalloc_node(droq->max_count *
293 						OCT_DROQ_RECVBUF_SIZE,
294 						numa_node);
295 	if (!droq->recv_buf_list)
296 		droq->recv_buf_list = (struct octeon_recv_buffer *)
297 				      vmalloc(droq->max_count *
298 						OCT_DROQ_RECVBUF_SIZE);
299 	if (!droq->recv_buf_list) {
300 		dev_err(&oct->pci_dev->dev, "Output queue recv buf list alloc failed\n");
301 		goto init_droq_fail;
302 	}
303 
304 	if (octeon_droq_setup_ring_buffers(oct, droq))
305 		goto init_droq_fail;
306 
307 	droq->pkts_per_intr = c_pkts_per_intr;
308 	droq->refill_threshold = c_refill_threshold;
309 
310 	dev_dbg(&oct->pci_dev->dev, "DROQ INIT: max_empty_descs: %d\n",
311 		droq->max_empty_descs);
312 
313 	spin_lock_init(&droq->lock);
314 
315 	INIT_LIST_HEAD(&droq->dispatch_list);
316 
317 	/* For 56xx Pass1, this function won't be called, so no checks. */
318 	oct->fn_list.setup_oq_regs(oct, q_no);
319 
320 	oct->io_qmask.oq |= BIT_ULL(q_no);
321 
322 	return 0;
323 
324 init_droq_fail:
325 	octeon_delete_droq(oct, q_no);
326 	return 1;
327 }
328 
329 /* octeon_create_recv_info
330  * Parameters:
331  *  octeon_dev - pointer to the octeon device structure
332  *  droq       - droq in which the packet arrived.
333  *  buf_cnt    - no. of buffers used by the packet.
334  *  idx        - index in the descriptor for the first buffer in the packet.
335  * Description:
336  *  Allocates a recv_info_t and copies the buffer addresses for packet data
337  *  into the recv_pkt space which starts at an 8B offset from recv_info_t.
338  *  Flags the descriptors for refill later. If available descriptors go
339  *  below the threshold to receive a 64K pkt, new buffers are first allocated
340  *  before the recv_pkt_t is created.
341  *  This routine will be called in interrupt context.
342  * Returns:
343  *  Success: Pointer to recv_info_t
344  *  Failure: NULL.
345  * Locks:
346  *  The droq->lock is held when this routine is called.
347  */
348 static inline struct octeon_recv_info *octeon_create_recv_info(
349 		struct octeon_device *octeon_dev,
350 		struct octeon_droq *droq,
351 		u32 buf_cnt,
352 		u32 idx)
353 {
354 	struct octeon_droq_info *info;
355 	struct octeon_recv_pkt *recv_pkt;
356 	struct octeon_recv_info *recv_info;
357 	u32 i, bytes_left;
358 	struct octeon_skb_page_info *pg_info;
359 
360 	info = &droq->info_list[idx];
361 
362 	recv_info = octeon_alloc_recv_info(sizeof(struct __dispatch));
363 	if (!recv_info)
364 		return NULL;
365 
366 	recv_pkt = recv_info->recv_pkt;
367 	recv_pkt->rh = info->rh;
368 	recv_pkt->length = (u32)info->length;
369 	recv_pkt->buffer_count = (u16)buf_cnt;
370 	recv_pkt->octeon_id = (u16)octeon_dev->octeon_id;
371 
372 	i = 0;
373 	bytes_left = (u32)info->length;
374 
375 	while (buf_cnt) {
376 		{
377 			pg_info = &droq->recv_buf_list[idx].pg_info;
378 
379 			lio_unmap_ring(octeon_dev->pci_dev,
380 				       (u64)pg_info->dma);
381 			pg_info->page = NULL;
382 			pg_info->dma = 0;
383 		}
384 
385 		recv_pkt->buffer_size[i] =
386 			(bytes_left >=
387 			 droq->buffer_size) ? droq->buffer_size : bytes_left;
388 
389 		recv_pkt->buffer_ptr[i] = droq->recv_buf_list[idx].buffer;
390 		droq->recv_buf_list[idx].buffer = NULL;
391 
392 		idx = incr_index(idx, 1, droq->max_count);
393 		bytes_left -= droq->buffer_size;
394 		i++;
395 		buf_cnt--;
396 	}
397 
398 	return recv_info;
399 }
400 
401 /* If we were not able to refill all buffers, try to move around
402  * the buffers that were not dispatched.
403  */
404 static inline u32
405 octeon_droq_refill_pullup_descs(struct octeon_droq *droq,
406 				struct octeon_droq_desc *desc_ring)
407 {
408 	u32 desc_refilled = 0;
409 
410 	u32 refill_index = droq->refill_idx;
411 
412 	while (refill_index != droq->read_idx) {
413 		if (droq->recv_buf_list[refill_index].buffer) {
414 			droq->recv_buf_list[droq->refill_idx].buffer =
415 				droq->recv_buf_list[refill_index].buffer;
416 			droq->recv_buf_list[droq->refill_idx].data =
417 				droq->recv_buf_list[refill_index].data;
418 			desc_ring[droq->refill_idx].buffer_ptr =
419 				desc_ring[refill_index].buffer_ptr;
420 			droq->recv_buf_list[refill_index].buffer = NULL;
421 			desc_ring[refill_index].buffer_ptr = 0;
422 			do {
423 				droq->refill_idx = incr_index(droq->refill_idx,
424 							      1,
425 							      droq->max_count);
426 				desc_refilled++;
427 				droq->refill_count--;
428 			} while (droq->recv_buf_list[droq->refill_idx].
429 				 buffer);
430 		}
431 		refill_index = incr_index(refill_index, 1, droq->max_count);
432 	}                       /* while */
433 	return desc_refilled;
434 }
435 
436 /* octeon_droq_refill
437  * Parameters:
438  *  droq       - droq in which descriptors require new buffers.
439  * Description:
440  *  Called during normal DROQ processing in interrupt mode or by the poll
441  *  thread to refill the descriptors from which buffers were dispatched
442  *  to upper layers. Attempts to allocate new buffers. If that fails, moves
443  *  up buffers (that were not dispatched) to form a contiguous ring.
444  * Returns:
445  *  No of descriptors refilled.
446  * Locks:
447  *  This routine is called with droq->lock held.
448  */
449 static u32
450 octeon_droq_refill(struct octeon_device *octeon_dev, struct octeon_droq *droq)
451 {
452 	struct octeon_droq_desc *desc_ring;
453 	void *buf = NULL;
454 	u8 *data;
455 	u32 desc_refilled = 0;
456 	struct octeon_skb_page_info *pg_info;
457 
458 	desc_ring = droq->desc_ring;
459 
460 	while (droq->refill_count && (desc_refilled < droq->max_count)) {
461 		/* If a valid buffer exists (happens if there is no dispatch),
462 		 * reuse
463 		 * the buffer, else allocate.
464 		 */
465 		if (!droq->recv_buf_list[droq->refill_idx].buffer) {
466 			pg_info =
467 				&droq->recv_buf_list[droq->refill_idx].pg_info;
468 			/* Either recycle the existing pages or go for
469 			 * new page alloc
470 			 */
471 			if (pg_info->page)
472 				buf = recv_buffer_reuse(octeon_dev, pg_info);
473 			else
474 				buf = recv_buffer_alloc(octeon_dev, pg_info);
475 			/* If a buffer could not be allocated, no point in
476 			 * continuing
477 			 */
478 			if (!buf) {
479 				droq->stats.rx_alloc_failure++;
480 				break;
481 			}
482 			droq->recv_buf_list[droq->refill_idx].buffer =
483 				buf;
484 			data = get_rbd(buf);
485 		} else {
486 			data = get_rbd(droq->recv_buf_list
487 				       [droq->refill_idx].buffer);
488 		}
489 
490 		droq->recv_buf_list[droq->refill_idx].data = data;
491 
492 		desc_ring[droq->refill_idx].buffer_ptr =
493 			lio_map_ring(droq->recv_buf_list[droq->
494 				     refill_idx].buffer);
495 		/* Reset any previous values in the length field. */
496 		droq->info_list[droq->refill_idx].length = 0;
497 
498 		droq->refill_idx = incr_index(droq->refill_idx, 1,
499 					      droq->max_count);
500 		desc_refilled++;
501 		droq->refill_count--;
502 	}
503 
504 	if (droq->refill_count)
505 		desc_refilled +=
506 			octeon_droq_refill_pullup_descs(droq, desc_ring);
507 
508 	/* if droq->refill_count
509 	 * The refill count would not change in pass two. We only moved buffers
510 	 * to close the gap in the ring, but we would still have the same no. of
511 	 * buffers to refill.
512 	 */
513 	return desc_refilled;
514 }
515 
516 /** check if we can allocate packets to get out of oom.
517  *  @param  droq - Droq being checked.
518  *  @return does not return anything
519  */
520 void octeon_droq_check_oom(struct octeon_droq *droq)
521 {
522 	int desc_refilled;
523 	struct octeon_device *oct = droq->oct_dev;
524 
525 	if (readl(droq->pkts_credit_reg) <= CN23XX_SLI_DEF_BP) {
526 		spin_lock_bh(&droq->lock);
527 		desc_refilled = octeon_droq_refill(oct, droq);
528 		if (desc_refilled) {
529 			/* Flush the droq descriptor data to memory to be sure
530 			 * that when we update the credits the data in memory
531 			 * is accurate.
532 			 */
533 			wmb();
534 			writel(desc_refilled, droq->pkts_credit_reg);
535 			/* make sure mmio write completes */
536 			mmiowb();
537 		}
538 		spin_unlock_bh(&droq->lock);
539 	}
540 }
541 
542 static inline u32
543 octeon_droq_get_bufcount(u32 buf_size, u32 total_len)
544 {
545 	u32 buf_cnt = 0;
546 
547 	while (total_len > (buf_size * buf_cnt))
548 		buf_cnt++;
549 	return buf_cnt;
550 }
551 
552 static int
553 octeon_droq_dispatch_pkt(struct octeon_device *oct,
554 			 struct octeon_droq *droq,
555 			 union octeon_rh *rh,
556 			 struct octeon_droq_info *info)
557 {
558 	u32 cnt;
559 	octeon_dispatch_fn_t disp_fn;
560 	struct octeon_recv_info *rinfo;
561 
562 	cnt = octeon_droq_get_bufcount(droq->buffer_size, (u32)info->length);
563 
564 	disp_fn = octeon_get_dispatch(oct, (u16)rh->r.opcode,
565 				      (u16)rh->r.subcode);
566 	if (disp_fn) {
567 		rinfo = octeon_create_recv_info(oct, droq, cnt, droq->read_idx);
568 		if (rinfo) {
569 			struct __dispatch *rdisp = rinfo->rsvd;
570 
571 			rdisp->rinfo = rinfo;
572 			rdisp->disp_fn = disp_fn;
573 			rinfo->recv_pkt->rh = *rh;
574 			list_add_tail(&rdisp->list,
575 				      &droq->dispatch_list);
576 		} else {
577 			droq->stats.dropped_nomem++;
578 		}
579 	} else {
580 		dev_err(&oct->pci_dev->dev, "DROQ: No dispatch function (opcode %u/%u)\n",
581 			(unsigned int)rh->r.opcode,
582 			(unsigned int)rh->r.subcode);
583 		droq->stats.dropped_nodispatch++;
584 	}
585 
586 	return cnt;
587 }
588 
589 static inline void octeon_droq_drop_packets(struct octeon_device *oct,
590 					    struct octeon_droq *droq,
591 					    u32 cnt)
592 {
593 	u32 i = 0, buf_cnt;
594 	struct octeon_droq_info *info;
595 
596 	for (i = 0; i < cnt; i++) {
597 		info = &droq->info_list[droq->read_idx];
598 		octeon_swap_8B_data((u64 *)info, 2);
599 
600 		if (info->length) {
601 			info->length -= OCT_RH_SIZE;
602 			droq->stats.bytes_received += info->length;
603 			buf_cnt = octeon_droq_get_bufcount(droq->buffer_size,
604 							   (u32)info->length);
605 		} else {
606 			dev_err(&oct->pci_dev->dev, "DROQ: In drop: pkt with len 0\n");
607 			buf_cnt = 1;
608 		}
609 
610 		droq->read_idx = incr_index(droq->read_idx, buf_cnt,
611 					    droq->max_count);
612 		droq->refill_count += buf_cnt;
613 	}
614 }
615 
616 static u32
617 octeon_droq_fast_process_packets(struct octeon_device *oct,
618 				 struct octeon_droq *droq,
619 				 u32 pkts_to_process)
620 {
621 	struct octeon_droq_info *info;
622 	union octeon_rh *rh;
623 	u32 pkt, total_len = 0, pkt_count;
624 
625 	pkt_count = pkts_to_process;
626 
627 	for (pkt = 0; pkt < pkt_count; pkt++) {
628 		u32 pkt_len = 0;
629 		struct sk_buff *nicbuf = NULL;
630 		struct octeon_skb_page_info *pg_info;
631 		void *buf;
632 
633 		info = &droq->info_list[droq->read_idx];
634 		octeon_swap_8B_data((u64 *)info, 2);
635 
636 		if (!info->length) {
637 			dev_err(&oct->pci_dev->dev,
638 				"DROQ[%d] idx: %d len:0, pkt_cnt: %d\n",
639 				droq->q_no, droq->read_idx, pkt_count);
640 			print_hex_dump_bytes("", DUMP_PREFIX_ADDRESS,
641 					     (u8 *)info,
642 					     OCT_DROQ_INFO_SIZE);
643 			break;
644 		}
645 
646 		/* Len of resp hdr in included in the received data len. */
647 		info->length -= OCT_RH_SIZE;
648 		rh = &info->rh;
649 
650 		total_len += (u32)info->length;
651 		if (opcode_slow_path(rh)) {
652 			u32 buf_cnt;
653 
654 			buf_cnt = octeon_droq_dispatch_pkt(oct, droq, rh, info);
655 			droq->read_idx = incr_index(droq->read_idx,
656 						    buf_cnt, droq->max_count);
657 			droq->refill_count += buf_cnt;
658 		} else {
659 			if (info->length <= droq->buffer_size) {
660 				pkt_len = (u32)info->length;
661 				nicbuf = droq->recv_buf_list[
662 					droq->read_idx].buffer;
663 				pg_info = &droq->recv_buf_list[
664 					droq->read_idx].pg_info;
665 				if (recv_buffer_recycle(oct, pg_info))
666 					pg_info->page = NULL;
667 				droq->recv_buf_list[droq->read_idx].buffer =
668 					NULL;
669 
670 				droq->read_idx = incr_index(droq->read_idx, 1,
671 							    droq->max_count);
672 				droq->refill_count++;
673 			} else {
674 				nicbuf = octeon_fast_packet_alloc((u32)
675 								  info->length);
676 				pkt_len = 0;
677 				/* nicbuf allocation can fail. We'll handle it
678 				 * inside the loop.
679 				 */
680 				while (pkt_len < info->length) {
681 					int cpy_len, idx = droq->read_idx;
682 
683 					cpy_len = ((pkt_len + droq->buffer_size)
684 						   > info->length) ?
685 						((u32)info->length - pkt_len) :
686 						droq->buffer_size;
687 
688 					if (nicbuf) {
689 						octeon_fast_packet_next(droq,
690 									nicbuf,
691 									cpy_len,
692 									idx);
693 						buf = droq->recv_buf_list[idx].
694 							buffer;
695 						recv_buffer_fast_free(buf);
696 						droq->recv_buf_list[idx].buffer
697 							= NULL;
698 					} else {
699 						droq->stats.rx_alloc_failure++;
700 					}
701 
702 					pkt_len += cpy_len;
703 					droq->read_idx =
704 						incr_index(droq->read_idx, 1,
705 							   droq->max_count);
706 					droq->refill_count++;
707 				}
708 			}
709 
710 			if (nicbuf) {
711 				if (droq->ops.fptr) {
712 					droq->ops.fptr(oct->octeon_id,
713 						       nicbuf, pkt_len,
714 						       rh, &droq->napi,
715 						       droq->ops.farg);
716 				} else {
717 					recv_buffer_free(nicbuf);
718 				}
719 			}
720 		}
721 
722 		if (droq->refill_count >= droq->refill_threshold) {
723 			int desc_refilled = octeon_droq_refill(oct, droq);
724 
725 			/* Flush the droq descriptor data to memory to be sure
726 			 * that when we update the credits the data in memory
727 			 * is accurate.
728 			 */
729 			wmb();
730 			writel((desc_refilled), droq->pkts_credit_reg);
731 			/* make sure mmio write completes */
732 			mmiowb();
733 		}
734 
735 	}                       /* for (each packet)... */
736 
737 	/* Increment refill_count by the number of buffers processed. */
738 	droq->stats.pkts_received += pkt;
739 	droq->stats.bytes_received += total_len;
740 
741 	if ((droq->ops.drop_on_max) && (pkts_to_process - pkt)) {
742 		octeon_droq_drop_packets(oct, droq, (pkts_to_process - pkt));
743 
744 		droq->stats.dropped_toomany += (pkts_to_process - pkt);
745 		return pkts_to_process;
746 	}
747 
748 	return pkt;
749 }
750 
751 int
752 octeon_droq_process_packets(struct octeon_device *oct,
753 			    struct octeon_droq *droq,
754 			    u32 budget)
755 {
756 	u32 pkt_count = 0, pkts_processed = 0;
757 	struct list_head *tmp, *tmp2;
758 
759 	/* Grab the droq lock */
760 	spin_lock(&droq->lock);
761 
762 	octeon_droq_check_hw_for_pkts(droq);
763 	pkt_count = atomic_read(&droq->pkts_pending);
764 
765 	if (!pkt_count) {
766 		spin_unlock(&droq->lock);
767 		return 0;
768 	}
769 
770 	if (pkt_count > budget)
771 		pkt_count = budget;
772 
773 	pkts_processed = octeon_droq_fast_process_packets(oct, droq, pkt_count);
774 
775 	atomic_sub(pkts_processed, &droq->pkts_pending);
776 
777 	/* Release the spin lock */
778 	spin_unlock(&droq->lock);
779 
780 	list_for_each_safe(tmp, tmp2, &droq->dispatch_list) {
781 		struct __dispatch *rdisp = (struct __dispatch *)tmp;
782 
783 		list_del(tmp);
784 		rdisp->disp_fn(rdisp->rinfo,
785 			       octeon_get_dispatch_arg
786 			       (oct,
787 				(u16)rdisp->rinfo->recv_pkt->rh.r.opcode,
788 				(u16)rdisp->rinfo->recv_pkt->rh.r.subcode));
789 	}
790 
791 	/* If there are packets pending. schedule tasklet again */
792 	if (atomic_read(&droq->pkts_pending))
793 		return 1;
794 
795 	return 0;
796 }
797 
798 /**
799  * Utility function to poll for packets. check_hw_for_packets must be
800  * called before calling this routine.
801  */
802 
803 static int
804 octeon_droq_process_poll_pkts(struct octeon_device *oct,
805 			      struct octeon_droq *droq, u32 budget)
806 {
807 	struct list_head *tmp, *tmp2;
808 	u32 pkts_available = 0, pkts_processed = 0;
809 	u32 total_pkts_processed = 0;
810 
811 	if (budget > droq->max_count)
812 		budget = droq->max_count;
813 
814 	spin_lock(&droq->lock);
815 
816 	while (total_pkts_processed < budget) {
817 		octeon_droq_check_hw_for_pkts(droq);
818 
819 		pkts_available = min((budget - total_pkts_processed),
820 				     (u32)(atomic_read(&droq->pkts_pending)));
821 
822 		if (pkts_available == 0)
823 			break;
824 
825 		pkts_processed =
826 			octeon_droq_fast_process_packets(oct, droq,
827 							 pkts_available);
828 
829 		atomic_sub(pkts_processed, &droq->pkts_pending);
830 
831 		total_pkts_processed += pkts_processed;
832 	}
833 
834 	spin_unlock(&droq->lock);
835 
836 	list_for_each_safe(tmp, tmp2, &droq->dispatch_list) {
837 		struct __dispatch *rdisp = (struct __dispatch *)tmp;
838 
839 		list_del(tmp);
840 		rdisp->disp_fn(rdisp->rinfo,
841 			       octeon_get_dispatch_arg
842 			       (oct,
843 				(u16)rdisp->rinfo->recv_pkt->rh.r.opcode,
844 				(u16)rdisp->rinfo->recv_pkt->rh.r.subcode));
845 	}
846 
847 	return total_pkts_processed;
848 }
849 
850 int
851 octeon_process_droq_poll_cmd(struct octeon_device *oct, u32 q_no, int cmd,
852 			     u32 arg)
853 {
854 	struct octeon_droq *droq;
855 
856 	droq = oct->droq[q_no];
857 
858 	if (cmd == POLL_EVENT_PROCESS_PKTS)
859 		return octeon_droq_process_poll_pkts(oct, droq, arg);
860 
861 	if (cmd == POLL_EVENT_PENDING_PKTS) {
862 		u32 pkt_cnt = atomic_read(&droq->pkts_pending);
863 
864 		return  octeon_droq_process_packets(oct, droq, pkt_cnt);
865 	}
866 
867 	if (cmd == POLL_EVENT_ENABLE_INTR) {
868 		u32 value;
869 		unsigned long flags;
870 
871 		/* Enable Pkt Interrupt */
872 		switch (oct->chip_id) {
873 		case OCTEON_CN66XX:
874 		case OCTEON_CN68XX: {
875 			struct octeon_cn6xxx *cn6xxx =
876 				(struct octeon_cn6xxx *)oct->chip;
877 			spin_lock_irqsave
878 				(&cn6xxx->lock_for_droq_int_enb_reg, flags);
879 			value =
880 				octeon_read_csr(oct,
881 						CN6XXX_SLI_PKT_TIME_INT_ENB);
882 			value |= (1 << q_no);
883 			octeon_write_csr(oct,
884 					 CN6XXX_SLI_PKT_TIME_INT_ENB,
885 					 value);
886 			value =
887 				octeon_read_csr(oct,
888 						CN6XXX_SLI_PKT_CNT_INT_ENB);
889 			value |= (1 << q_no);
890 			octeon_write_csr(oct,
891 					 CN6XXX_SLI_PKT_CNT_INT_ENB,
892 					 value);
893 
894 			/* don't bother flushing the enables */
895 
896 			spin_unlock_irqrestore
897 				(&cn6xxx->lock_for_droq_int_enb_reg, flags);
898 			return 0;
899 		}
900 		break;
901 		case OCTEON_CN23XX_PF_VID: {
902 			lio_enable_irq(oct->droq[q_no], oct->instr_queue[q_no]);
903 		}
904 		break;
905 
906 		case OCTEON_CN23XX_VF_VID:
907 			lio_enable_irq(oct->droq[q_no], oct->instr_queue[q_no]);
908 		break;
909 		}
910 		return 0;
911 	}
912 
913 	dev_err(&oct->pci_dev->dev, "%s Unknown command: %d\n", __func__, cmd);
914 	return -EINVAL;
915 }
916 
917 int octeon_register_droq_ops(struct octeon_device *oct, u32 q_no,
918 			     struct octeon_droq_ops *ops)
919 {
920 	struct octeon_droq *droq;
921 	unsigned long flags;
922 	struct octeon_config *oct_cfg = NULL;
923 
924 	oct_cfg = octeon_get_conf(oct);
925 
926 	if (!oct_cfg)
927 		return -EINVAL;
928 
929 	if (!(ops)) {
930 		dev_err(&oct->pci_dev->dev, "%s: droq_ops pointer is NULL\n",
931 			__func__);
932 		return -EINVAL;
933 	}
934 
935 	if (q_no >= CFG_GET_OQ_MAX_Q(oct_cfg)) {
936 		dev_err(&oct->pci_dev->dev, "%s: droq id (%d) exceeds MAX (%d)\n",
937 			__func__, q_no, (oct->num_oqs - 1));
938 		return -EINVAL;
939 	}
940 
941 	droq = oct->droq[q_no];
942 
943 	spin_lock_irqsave(&droq->lock, flags);
944 
945 	memcpy(&droq->ops, ops, sizeof(struct octeon_droq_ops));
946 
947 	spin_unlock_irqrestore(&droq->lock, flags);
948 
949 	return 0;
950 }
951 
952 int octeon_unregister_droq_ops(struct octeon_device *oct, u32 q_no)
953 {
954 	unsigned long flags;
955 	struct octeon_droq *droq;
956 	struct octeon_config *oct_cfg = NULL;
957 
958 	oct_cfg = octeon_get_conf(oct);
959 
960 	if (!oct_cfg)
961 		return -EINVAL;
962 
963 	if (q_no >= CFG_GET_OQ_MAX_Q(oct_cfg)) {
964 		dev_err(&oct->pci_dev->dev, "%s: droq id (%d) exceeds MAX (%d)\n",
965 			__func__, q_no, oct->num_oqs - 1);
966 		return -EINVAL;
967 	}
968 
969 	droq = oct->droq[q_no];
970 
971 	if (!droq) {
972 		dev_info(&oct->pci_dev->dev,
973 			 "Droq id (%d) not available.\n", q_no);
974 		return 0;
975 	}
976 
977 	spin_lock_irqsave(&droq->lock, flags);
978 
979 	droq->ops.fptr = NULL;
980 	droq->ops.farg = NULL;
981 	droq->ops.drop_on_max = 0;
982 
983 	spin_unlock_irqrestore(&droq->lock, flags);
984 
985 	return 0;
986 }
987 
988 int octeon_create_droq(struct octeon_device *oct,
989 		       u32 q_no, u32 num_descs,
990 		       u32 desc_size, void *app_ctx)
991 {
992 	struct octeon_droq *droq;
993 	int numa_node = dev_to_node(&oct->pci_dev->dev);
994 
995 	if (oct->droq[q_no]) {
996 		dev_dbg(&oct->pci_dev->dev, "Droq already in use. Cannot create droq %d again\n",
997 			q_no);
998 		return 1;
999 	}
1000 
1001 	/* Allocate the DS for the new droq. */
1002 	droq = vmalloc_node(sizeof(*droq), numa_node);
1003 	if (!droq)
1004 		droq = vmalloc(sizeof(*droq));
1005 	if (!droq)
1006 		return -1;
1007 
1008 	memset(droq, 0, sizeof(struct octeon_droq));
1009 
1010 	/*Disable the pkt o/p for this Q  */
1011 	octeon_set_droq_pkt_op(oct, q_no, 0);
1012 	oct->droq[q_no] = droq;
1013 
1014 	/* Initialize the Droq */
1015 	if (octeon_init_droq(oct, q_no, num_descs, desc_size, app_ctx)) {
1016 		vfree(oct->droq[q_no]);
1017 		oct->droq[q_no] = NULL;
1018 		return -1;
1019 	}
1020 
1021 	oct->num_oqs++;
1022 
1023 	dev_dbg(&oct->pci_dev->dev, "%s: Total number of OQ: %d\n", __func__,
1024 		oct->num_oqs);
1025 
1026 	/* Global Droq register settings */
1027 
1028 	/* As of now not required, as setting are done for all 32 Droqs at
1029 	 * the same time.
1030 	 */
1031 	return 0;
1032 }
1033