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 = vzalloc_node(array_size(droq->max_count, OCT_DROQ_RECVBUF_SIZE),
284 					   numa_node);
285 	if (!droq->recv_buf_list)
286 		droq->recv_buf_list = vzalloc(array_size(droq->max_count, OCT_DROQ_RECVBUF_SIZE));
287 	if (!droq->recv_buf_list) {
288 		dev_err(&oct->pci_dev->dev, "Output queue recv buf list alloc failed\n");
289 		goto init_droq_fail;
290 	}
291 
292 	if (octeon_droq_setup_ring_buffers(oct, droq))
293 		goto init_droq_fail;
294 
295 	droq->pkts_per_intr = c_pkts_per_intr;
296 	droq->refill_threshold = c_refill_threshold;
297 
298 	dev_dbg(&oct->pci_dev->dev, "DROQ INIT: max_empty_descs: %d\n",
299 		droq->max_empty_descs);
300 
301 	INIT_LIST_HEAD(&droq->dispatch_list);
302 
303 	/* For 56xx Pass1, this function won't be called, so no checks. */
304 	oct->fn_list.setup_oq_regs(oct, q_no);
305 
306 	oct->io_qmask.oq |= BIT_ULL(q_no);
307 
308 	return 0;
309 
310 init_droq_fail:
311 	octeon_delete_droq(oct, q_no);
312 	return 1;
313 }
314 
315 /* octeon_create_recv_info
316  * Parameters:
317  *  octeon_dev - pointer to the octeon device structure
318  *  droq       - droq in which the packet arrived.
319  *  buf_cnt    - no. of buffers used by the packet.
320  *  idx        - index in the descriptor for the first buffer in the packet.
321  * Description:
322  *  Allocates a recv_info_t and copies the buffer addresses for packet data
323  *  into the recv_pkt space which starts at an 8B offset from recv_info_t.
324  *  Flags the descriptors for refill later. If available descriptors go
325  *  below the threshold to receive a 64K pkt, new buffers are first allocated
326  *  before the recv_pkt_t is created.
327  *  This routine will be called in interrupt context.
328  * Returns:
329  *  Success: Pointer to recv_info_t
330  *  Failure: NULL.
331  */
332 static inline struct octeon_recv_info *octeon_create_recv_info(
333 		struct octeon_device *octeon_dev,
334 		struct octeon_droq *droq,
335 		u32 buf_cnt,
336 		u32 idx)
337 {
338 	struct octeon_droq_info *info;
339 	struct octeon_recv_pkt *recv_pkt;
340 	struct octeon_recv_info *recv_info;
341 	u32 i, bytes_left;
342 	struct octeon_skb_page_info *pg_info;
343 
344 	info = (struct octeon_droq_info *)droq->recv_buf_list[idx].data;
345 
346 	recv_info = octeon_alloc_recv_info(sizeof(struct __dispatch));
347 	if (!recv_info)
348 		return NULL;
349 
350 	recv_pkt = recv_info->recv_pkt;
351 	recv_pkt->rh = info->rh;
352 	recv_pkt->length = (u32)info->length;
353 	recv_pkt->buffer_count = (u16)buf_cnt;
354 	recv_pkt->octeon_id = (u16)octeon_dev->octeon_id;
355 
356 	i = 0;
357 	bytes_left = (u32)info->length;
358 
359 	while (buf_cnt) {
360 		{
361 			pg_info = &droq->recv_buf_list[idx].pg_info;
362 
363 			lio_unmap_ring(octeon_dev->pci_dev,
364 				       (u64)pg_info->dma);
365 			pg_info->page = NULL;
366 			pg_info->dma = 0;
367 		}
368 
369 		recv_pkt->buffer_size[i] =
370 			(bytes_left >=
371 			 droq->buffer_size) ? droq->buffer_size : bytes_left;
372 
373 		recv_pkt->buffer_ptr[i] = droq->recv_buf_list[idx].buffer;
374 		droq->recv_buf_list[idx].buffer = NULL;
375 
376 		idx = incr_index(idx, 1, droq->max_count);
377 		bytes_left -= droq->buffer_size;
378 		i++;
379 		buf_cnt--;
380 	}
381 
382 	return recv_info;
383 }
384 
385 /* If we were not able to refill all buffers, try to move around
386  * the buffers that were not dispatched.
387  */
388 static inline u32
389 octeon_droq_refill_pullup_descs(struct octeon_droq *droq,
390 				struct octeon_droq_desc *desc_ring)
391 {
392 	u32 desc_refilled = 0;
393 
394 	u32 refill_index = droq->refill_idx;
395 
396 	while (refill_index != droq->read_idx) {
397 		if (droq->recv_buf_list[refill_index].buffer) {
398 			droq->recv_buf_list[droq->refill_idx].buffer =
399 				droq->recv_buf_list[refill_index].buffer;
400 			droq->recv_buf_list[droq->refill_idx].data =
401 				droq->recv_buf_list[refill_index].data;
402 			desc_ring[droq->refill_idx].buffer_ptr =
403 				desc_ring[refill_index].buffer_ptr;
404 			droq->recv_buf_list[refill_index].buffer = NULL;
405 			desc_ring[refill_index].buffer_ptr = 0;
406 			do {
407 				droq->refill_idx = incr_index(droq->refill_idx,
408 							      1,
409 							      droq->max_count);
410 				desc_refilled++;
411 				droq->refill_count--;
412 			} while (droq->recv_buf_list[droq->refill_idx].buffer);
413 		}
414 		refill_index = incr_index(refill_index, 1, droq->max_count);
415 	}                       /* while */
416 	return desc_refilled;
417 }
418 
419 /* octeon_droq_refill
420  * Parameters:
421  *  droq       - droq in which descriptors require new buffers.
422  * Description:
423  *  Called during normal DROQ processing in interrupt mode or by the poll
424  *  thread to refill the descriptors from which buffers were dispatched
425  *  to upper layers. Attempts to allocate new buffers. If that fails, moves
426  *  up buffers (that were not dispatched) to form a contiguous ring.
427  * Returns:
428  *  No of descriptors refilled.
429  */
430 static u32
431 octeon_droq_refill(struct octeon_device *octeon_dev, struct octeon_droq *droq)
432 {
433 	struct octeon_droq_desc *desc_ring;
434 	void *buf = NULL;
435 	u8 *data;
436 	u32 desc_refilled = 0;
437 	struct octeon_skb_page_info *pg_info;
438 
439 	desc_ring = droq->desc_ring;
440 
441 	while (droq->refill_count && (desc_refilled < droq->max_count)) {
442 		/* If a valid buffer exists (happens if there is no dispatch),
443 		 * reuse the buffer, else allocate.
444 		 */
445 		if (!droq->recv_buf_list[droq->refill_idx].buffer) {
446 			pg_info =
447 				&droq->recv_buf_list[droq->refill_idx].pg_info;
448 			/* Either recycle the existing pages or go for
449 			 * new page alloc
450 			 */
451 			if (pg_info->page)
452 				buf = recv_buffer_reuse(octeon_dev, pg_info);
453 			else
454 				buf = recv_buffer_alloc(octeon_dev, pg_info);
455 			/* If a buffer could not be allocated, no point in
456 			 * continuing
457 			 */
458 			if (!buf) {
459 				droq->stats.rx_alloc_failure++;
460 				break;
461 			}
462 			droq->recv_buf_list[droq->refill_idx].buffer =
463 				buf;
464 			data = get_rbd(buf);
465 		} else {
466 			data = get_rbd(droq->recv_buf_list
467 				       [droq->refill_idx].buffer);
468 		}
469 
470 		droq->recv_buf_list[droq->refill_idx].data = data;
471 
472 		desc_ring[droq->refill_idx].buffer_ptr =
473 			lio_map_ring(droq->recv_buf_list[
474 				     droq->refill_idx].buffer);
475 
476 		droq->refill_idx = incr_index(droq->refill_idx, 1,
477 					      droq->max_count);
478 		desc_refilled++;
479 		droq->refill_count--;
480 	}
481 
482 	if (droq->refill_count)
483 		desc_refilled +=
484 			octeon_droq_refill_pullup_descs(droq, desc_ring);
485 
486 	/* if droq->refill_count
487 	 * The refill count would not change in pass two. We only moved buffers
488 	 * to close the gap in the ring, but we would still have the same no. of
489 	 * buffers to refill.
490 	 */
491 	return desc_refilled;
492 }
493 
494 /** check if we can allocate packets to get out of oom.
495  *  @param  droq - Droq being checked.
496  *  @return 1 if fails to refill minimum
497  */
498 int octeon_retry_droq_refill(struct octeon_droq *droq)
499 {
500 	struct octeon_device *oct = droq->oct_dev;
501 	int desc_refilled, reschedule = 1;
502 	u32 pkts_credit;
503 
504 	pkts_credit = readl(droq->pkts_credit_reg);
505 	desc_refilled = octeon_droq_refill(oct, droq);
506 	if (desc_refilled) {
507 		/* Flush the droq descriptor data to memory to be sure
508 		 * that when we update the credits the data in memory
509 		 * is accurate.
510 		 */
511 		wmb();
512 		writel(desc_refilled, droq->pkts_credit_reg);
513 
514 		if (pkts_credit + desc_refilled >= CN23XX_SLI_DEF_BP)
515 			reschedule = 0;
516 	}
517 
518 	return reschedule;
519 }
520 
521 static inline u32
522 octeon_droq_get_bufcount(u32 buf_size, u32 total_len)
523 {
524 	return DIV_ROUND_UP(total_len, buf_size);
525 }
526 
527 static int
528 octeon_droq_dispatch_pkt(struct octeon_device *oct,
529 			 struct octeon_droq *droq,
530 			 union octeon_rh *rh,
531 			 struct octeon_droq_info *info)
532 {
533 	u32 cnt;
534 	octeon_dispatch_fn_t disp_fn;
535 	struct octeon_recv_info *rinfo;
536 
537 	cnt = octeon_droq_get_bufcount(droq->buffer_size, (u32)info->length);
538 
539 	disp_fn = octeon_get_dispatch(oct, (u16)rh->r.opcode,
540 				      (u16)rh->r.subcode);
541 	if (disp_fn) {
542 		rinfo = octeon_create_recv_info(oct, droq, cnt, droq->read_idx);
543 		if (rinfo) {
544 			struct __dispatch *rdisp = rinfo->rsvd;
545 
546 			rdisp->rinfo = rinfo;
547 			rdisp->disp_fn = disp_fn;
548 			rinfo->recv_pkt->rh = *rh;
549 			list_add_tail(&rdisp->list,
550 				      &droq->dispatch_list);
551 		} else {
552 			droq->stats.dropped_nomem++;
553 		}
554 	} else {
555 		dev_err(&oct->pci_dev->dev, "DROQ: No dispatch function (opcode %u/%u)\n",
556 			(unsigned int)rh->r.opcode,
557 			(unsigned int)rh->r.subcode);
558 		droq->stats.dropped_nodispatch++;
559 	}
560 
561 	return cnt;
562 }
563 
564 static inline void octeon_droq_drop_packets(struct octeon_device *oct,
565 					    struct octeon_droq *droq,
566 					    u32 cnt)
567 {
568 	u32 i = 0, buf_cnt;
569 	struct octeon_droq_info *info;
570 
571 	for (i = 0; i < cnt; i++) {
572 		info = (struct octeon_droq_info *)
573 			droq->recv_buf_list[droq->read_idx].data;
574 		octeon_swap_8B_data((u64 *)info, 2);
575 
576 		if (info->length) {
577 			info->length += OCTNET_FRM_LENGTH_SIZE;
578 			droq->stats.bytes_received += info->length;
579 			buf_cnt = octeon_droq_get_bufcount(droq->buffer_size,
580 							   (u32)info->length);
581 		} else {
582 			dev_err(&oct->pci_dev->dev, "DROQ: In drop: pkt with len 0\n");
583 			buf_cnt = 1;
584 		}
585 
586 		droq->read_idx = incr_index(droq->read_idx, buf_cnt,
587 					    droq->max_count);
588 		droq->refill_count += buf_cnt;
589 	}
590 }
591 
592 static u32
593 octeon_droq_fast_process_packets(struct octeon_device *oct,
594 				 struct octeon_droq *droq,
595 				 u32 pkts_to_process)
596 {
597 	u32 pkt, total_len = 0, pkt_count, retval;
598 	struct octeon_droq_info *info;
599 	union octeon_rh *rh;
600 
601 	pkt_count = pkts_to_process;
602 
603 	for (pkt = 0; pkt < pkt_count; pkt++) {
604 		u32 pkt_len = 0;
605 		struct sk_buff *nicbuf = NULL;
606 		struct octeon_skb_page_info *pg_info;
607 		void *buf;
608 
609 		info = (struct octeon_droq_info *)
610 			droq->recv_buf_list[droq->read_idx].data;
611 		octeon_swap_8B_data((u64 *)info, 2);
612 
613 		if (!info->length) {
614 			dev_err(&oct->pci_dev->dev,
615 				"DROQ[%d] idx: %d len:0, pkt_cnt: %d\n",
616 				droq->q_no, droq->read_idx, pkt_count);
617 			print_hex_dump_bytes("", DUMP_PREFIX_ADDRESS,
618 					     (u8 *)info,
619 					     OCT_DROQ_INFO_SIZE);
620 			break;
621 		}
622 
623 		/* Len of resp hdr in included in the received data len. */
624 		rh = &info->rh;
625 
626 		info->length += OCTNET_FRM_LENGTH_SIZE;
627 		rh->r_dh.len += (ROUNDUP8(OCT_DROQ_INFO_SIZE) / sizeof(u64));
628 		total_len += (u32)info->length;
629 		if (opcode_slow_path(rh)) {
630 			u32 buf_cnt;
631 
632 			buf_cnt = octeon_droq_dispatch_pkt(oct, droq, rh, info);
633 			droq->read_idx = incr_index(droq->read_idx,
634 						    buf_cnt, droq->max_count);
635 			droq->refill_count += buf_cnt;
636 		} else {
637 			if (info->length <= droq->buffer_size) {
638 				pkt_len = (u32)info->length;
639 				nicbuf = droq->recv_buf_list[
640 					droq->read_idx].buffer;
641 				pg_info = &droq->recv_buf_list[
642 					droq->read_idx].pg_info;
643 				if (recv_buffer_recycle(oct, pg_info))
644 					pg_info->page = NULL;
645 				droq->recv_buf_list[droq->read_idx].buffer =
646 					NULL;
647 
648 				droq->read_idx = incr_index(droq->read_idx, 1,
649 							    droq->max_count);
650 				droq->refill_count++;
651 			} else {
652 				nicbuf = octeon_fast_packet_alloc((u32)
653 								  info->length);
654 				pkt_len = 0;
655 				/* nicbuf allocation can fail. We'll handle it
656 				 * inside the loop.
657 				 */
658 				while (pkt_len < info->length) {
659 					int cpy_len, idx = droq->read_idx;
660 
661 					cpy_len = ((pkt_len + droq->buffer_size)
662 						   > info->length) ?
663 						((u32)info->length - pkt_len) :
664 						droq->buffer_size;
665 
666 					if (nicbuf) {
667 						octeon_fast_packet_next(droq,
668 									nicbuf,
669 									cpy_len,
670 									idx);
671 						buf = droq->recv_buf_list[
672 							idx].buffer;
673 						recv_buffer_fast_free(buf);
674 						droq->recv_buf_list[idx].buffer
675 							= NULL;
676 					} else {
677 						droq->stats.rx_alloc_failure++;
678 					}
679 
680 					pkt_len += cpy_len;
681 					droq->read_idx =
682 						incr_index(droq->read_idx, 1,
683 							   droq->max_count);
684 					droq->refill_count++;
685 				}
686 			}
687 
688 			if (nicbuf) {
689 				if (droq->ops.fptr) {
690 					droq->ops.fptr(oct->octeon_id,
691 						       nicbuf, pkt_len,
692 						       rh, &droq->napi,
693 						       droq->ops.farg);
694 				} else {
695 					recv_buffer_free(nicbuf);
696 				}
697 			}
698 		}
699 
700 		if (droq->refill_count >= droq->refill_threshold) {
701 			int desc_refilled = octeon_droq_refill(oct, droq);
702 
703 			if (desc_refilled) {
704 				/* Flush the droq descriptor data to memory to
705 				 * be sure that when we update the credits the
706 				 * data in memory is accurate.
707 				 */
708 				wmb();
709 				writel(desc_refilled, droq->pkts_credit_reg);
710 			}
711 		}
712 	}                       /* for (each packet)... */
713 
714 	/* Increment refill_count by the number of buffers processed. */
715 	droq->stats.pkts_received += pkt;
716 	droq->stats.bytes_received += total_len;
717 
718 	retval = pkt;
719 	if ((droq->ops.drop_on_max) && (pkts_to_process - pkt)) {
720 		octeon_droq_drop_packets(oct, droq, (pkts_to_process - pkt));
721 
722 		droq->stats.dropped_toomany += (pkts_to_process - pkt);
723 		retval = pkts_to_process;
724 	}
725 
726 	atomic_sub(retval, &droq->pkts_pending);
727 
728 	if (droq->refill_count >= droq->refill_threshold &&
729 	    readl(droq->pkts_credit_reg) < CN23XX_SLI_DEF_BP) {
730 		octeon_droq_check_hw_for_pkts(droq);
731 
732 		/* Make sure there are no pkts_pending */
733 		if (!atomic_read(&droq->pkts_pending))
734 			octeon_schedule_rxq_oom_work(oct, droq);
735 	}
736 
737 	return retval;
738 }
739 
740 int
741 octeon_droq_process_packets(struct octeon_device *oct,
742 			    struct octeon_droq *droq,
743 			    u32 budget)
744 {
745 	u32 pkt_count = 0;
746 	struct list_head *tmp, *tmp2;
747 
748 	octeon_droq_check_hw_for_pkts(droq);
749 	pkt_count = atomic_read(&droq->pkts_pending);
750 
751 	if (!pkt_count)
752 		return 0;
753 
754 	if (pkt_count > budget)
755 		pkt_count = budget;
756 
757 	octeon_droq_fast_process_packets(oct, droq, pkt_count);
758 
759 	list_for_each_safe(tmp, tmp2, &droq->dispatch_list) {
760 		struct __dispatch *rdisp = (struct __dispatch *)tmp;
761 
762 		list_del(tmp);
763 		rdisp->disp_fn(rdisp->rinfo,
764 			       octeon_get_dispatch_arg
765 			       (oct,
766 				(u16)rdisp->rinfo->recv_pkt->rh.r.opcode,
767 				(u16)rdisp->rinfo->recv_pkt->rh.r.subcode));
768 	}
769 
770 	/* If there are packets pending. schedule tasklet again */
771 	if (atomic_read(&droq->pkts_pending))
772 		return 1;
773 
774 	return 0;
775 }
776 
777 /*
778  * Utility function to poll for packets. check_hw_for_packets must be
779  * called before calling this routine.
780  */
781 
782 int
783 octeon_droq_process_poll_pkts(struct octeon_device *oct,
784 			      struct octeon_droq *droq, u32 budget)
785 {
786 	struct list_head *tmp, *tmp2;
787 	u32 pkts_available = 0, pkts_processed = 0;
788 	u32 total_pkts_processed = 0;
789 
790 	if (budget > droq->max_count)
791 		budget = droq->max_count;
792 
793 	while (total_pkts_processed < budget) {
794 		octeon_droq_check_hw_for_pkts(droq);
795 
796 		pkts_available = min((budget - total_pkts_processed),
797 				     (u32)(atomic_read(&droq->pkts_pending)));
798 
799 		if (pkts_available == 0)
800 			break;
801 
802 		pkts_processed =
803 			octeon_droq_fast_process_packets(oct, droq,
804 							 pkts_available);
805 
806 		total_pkts_processed += pkts_processed;
807 	}
808 
809 	list_for_each_safe(tmp, tmp2, &droq->dispatch_list) {
810 		struct __dispatch *rdisp = (struct __dispatch *)tmp;
811 
812 		list_del(tmp);
813 		rdisp->disp_fn(rdisp->rinfo,
814 			       octeon_get_dispatch_arg
815 			       (oct,
816 				(u16)rdisp->rinfo->recv_pkt->rh.r.opcode,
817 				(u16)rdisp->rinfo->recv_pkt->rh.r.subcode));
818 	}
819 
820 	return total_pkts_processed;
821 }
822 
823 /* Enable Pkt Interrupt */
824 int
825 octeon_enable_irq(struct octeon_device *oct, u32 q_no)
826 {
827 	switch (oct->chip_id) {
828 	case OCTEON_CN66XX:
829 	case OCTEON_CN68XX: {
830 		struct octeon_cn6xxx *cn6xxx =
831 			(struct octeon_cn6xxx *)oct->chip;
832 		unsigned long flags;
833 		u32 value;
834 
835 		spin_lock_irqsave
836 			(&cn6xxx->lock_for_droq_int_enb_reg, flags);
837 		value = octeon_read_csr(oct, CN6XXX_SLI_PKT_TIME_INT_ENB);
838 		value |= (1 << q_no);
839 		octeon_write_csr(oct, CN6XXX_SLI_PKT_TIME_INT_ENB, value);
840 		value = octeon_read_csr(oct, CN6XXX_SLI_PKT_CNT_INT_ENB);
841 		value |= (1 << q_no);
842 		octeon_write_csr(oct, CN6XXX_SLI_PKT_CNT_INT_ENB, value);
843 
844 		/* don't bother flushing the enables */
845 
846 		spin_unlock_irqrestore
847 			(&cn6xxx->lock_for_droq_int_enb_reg, flags);
848 	}
849 		break;
850 	case OCTEON_CN23XX_PF_VID:
851 		lio_enable_irq(oct->droq[q_no], oct->instr_queue[q_no]);
852 		break;
853 
854 	case OCTEON_CN23XX_VF_VID:
855 		lio_enable_irq(oct->droq[q_no], oct->instr_queue[q_no]);
856 		break;
857 	default:
858 		dev_err(&oct->pci_dev->dev, "%s Unknown Chip\n", __func__);
859 		return 1;
860 	}
861 
862 	return 0;
863 }
864 
865 int octeon_register_droq_ops(struct octeon_device *oct, u32 q_no,
866 			     struct octeon_droq_ops *ops)
867 {
868 	struct octeon_config *oct_cfg = NULL;
869 	struct octeon_droq *droq;
870 
871 	oct_cfg = octeon_get_conf(oct);
872 
873 	if (!oct_cfg)
874 		return -EINVAL;
875 
876 	if (!(ops)) {
877 		dev_err(&oct->pci_dev->dev, "%s: droq_ops pointer is NULL\n",
878 			__func__);
879 		return -EINVAL;
880 	}
881 
882 	if (q_no >= CFG_GET_OQ_MAX_Q(oct_cfg)) {
883 		dev_err(&oct->pci_dev->dev, "%s: droq id (%d) exceeds MAX (%d)\n",
884 			__func__, q_no, (oct->num_oqs - 1));
885 		return -EINVAL;
886 	}
887 
888 	droq = oct->droq[q_no];
889 	memcpy(&droq->ops, ops, sizeof(struct octeon_droq_ops));
890 
891 	return 0;
892 }
893 
894 int octeon_unregister_droq_ops(struct octeon_device *oct, u32 q_no)
895 {
896 	struct octeon_config *oct_cfg = NULL;
897 	struct octeon_droq *droq;
898 
899 	oct_cfg = octeon_get_conf(oct);
900 
901 	if (!oct_cfg)
902 		return -EINVAL;
903 
904 	if (q_no >= CFG_GET_OQ_MAX_Q(oct_cfg)) {
905 		dev_err(&oct->pci_dev->dev, "%s: droq id (%d) exceeds MAX (%d)\n",
906 			__func__, q_no, oct->num_oqs - 1);
907 		return -EINVAL;
908 	}
909 
910 	droq = oct->droq[q_no];
911 
912 	if (!droq) {
913 		dev_info(&oct->pci_dev->dev,
914 			 "Droq id (%d) not available.\n", q_no);
915 		return 0;
916 	}
917 
918 	droq->ops.fptr = NULL;
919 	droq->ops.farg = NULL;
920 	droq->ops.drop_on_max = 0;
921 
922 	return 0;
923 }
924 
925 int octeon_create_droq(struct octeon_device *oct,
926 		       u32 q_no, u32 num_descs,
927 		       u32 desc_size, void *app_ctx)
928 {
929 	struct octeon_droq *droq;
930 	int numa_node = dev_to_node(&oct->pci_dev->dev);
931 
932 	if (oct->droq[q_no]) {
933 		dev_dbg(&oct->pci_dev->dev, "Droq already in use. Cannot create droq %d again\n",
934 			q_no);
935 		return 1;
936 	}
937 
938 	/* Allocate the DS for the new droq. */
939 	droq = vmalloc_node(sizeof(*droq), numa_node);
940 	if (!droq)
941 		droq = vmalloc(sizeof(*droq));
942 	if (!droq)
943 		return -1;
944 
945 	memset(droq, 0, sizeof(struct octeon_droq));
946 
947 	/*Disable the pkt o/p for this Q  */
948 	octeon_set_droq_pkt_op(oct, q_no, 0);
949 	oct->droq[q_no] = droq;
950 
951 	/* Initialize the Droq */
952 	if (octeon_init_droq(oct, q_no, num_descs, desc_size, app_ctx)) {
953 		vfree(oct->droq[q_no]);
954 		oct->droq[q_no] = NULL;
955 		return -1;
956 	}
957 
958 	oct->num_oqs++;
959 
960 	dev_dbg(&oct->pci_dev->dev, "%s: Total number of OQ: %d\n", __func__,
961 		oct->num_oqs);
962 
963 	/* Global Droq register settings */
964 
965 	/* As of now not required, as setting are done for all 32 Droqs at
966 	 * the same time.
967 	 */
968 	return 0;
969 }
970