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 		desc_ring[i].info_ptr = 0;
185 		desc_ring[i].buffer_ptr =
186 			lio_map_ring(droq->recv_buf_list[i].buffer);
187 	}
188 
189 	octeon_droq_reset_indices(droq);
190 
191 	octeon_droq_compute_max_packet_bufs(droq);
192 
193 	return 0;
194 }
195 
196 int octeon_delete_droq(struct octeon_device *oct, u32 q_no)
197 {
198 	struct octeon_droq *droq = oct->droq[q_no];
199 
200 	dev_dbg(&oct->pci_dev->dev, "%s[%d]\n", __func__, q_no);
201 
202 	octeon_droq_destroy_ring_buffers(oct, droq);
203 	vfree(droq->recv_buf_list);
204 
205 	if (droq->desc_ring)
206 		lio_dma_free(oct, (droq->max_count * OCT_DROQ_DESC_SIZE),
207 			     droq->desc_ring, droq->desc_ring_dma);
208 
209 	memset(droq, 0, OCT_DROQ_SIZE);
210 
211 	return 0;
212 }
213 
214 int octeon_init_droq(struct octeon_device *oct,
215 		     u32 q_no,
216 		     u32 num_descs,
217 		     u32 desc_size,
218 		     void *app_ctx)
219 {
220 	struct octeon_droq *droq;
221 	u32 desc_ring_size = 0, c_num_descs = 0, c_buf_size = 0;
222 	u32 c_pkts_per_intr = 0, c_refill_threshold = 0;
223 	int numa_node = dev_to_node(&oct->pci_dev->dev);
224 
225 	dev_dbg(&oct->pci_dev->dev, "%s[%d]\n", __func__, q_no);
226 
227 	droq = oct->droq[q_no];
228 	memset(droq, 0, OCT_DROQ_SIZE);
229 
230 	droq->oct_dev = oct;
231 	droq->q_no = q_no;
232 	if (app_ctx)
233 		droq->app_ctx = app_ctx;
234 	else
235 		droq->app_ctx = (void *)(size_t)q_no;
236 
237 	c_num_descs = num_descs;
238 	c_buf_size = desc_size;
239 	if (OCTEON_CN6XXX(oct)) {
240 		struct octeon_config *conf6x = CHIP_CONF(oct, cn6xxx);
241 
242 		c_pkts_per_intr = (u32)CFG_GET_OQ_PKTS_PER_INTR(conf6x);
243 		c_refill_threshold =
244 			(u32)CFG_GET_OQ_REFILL_THRESHOLD(conf6x);
245 	} else if (OCTEON_CN23XX_PF(oct)) {
246 		struct octeon_config *conf23 = CHIP_CONF(oct, cn23xx_pf);
247 
248 		c_pkts_per_intr = (u32)CFG_GET_OQ_PKTS_PER_INTR(conf23);
249 		c_refill_threshold = (u32)CFG_GET_OQ_REFILL_THRESHOLD(conf23);
250 	} else if (OCTEON_CN23XX_VF(oct)) {
251 		struct octeon_config *conf23 = CHIP_CONF(oct, cn23xx_vf);
252 
253 		c_pkts_per_intr = (u32)CFG_GET_OQ_PKTS_PER_INTR(conf23);
254 		c_refill_threshold = (u32)CFG_GET_OQ_REFILL_THRESHOLD(conf23);
255 	} else {
256 		return 1;
257 	}
258 
259 	droq->max_count = c_num_descs;
260 	droq->buffer_size = c_buf_size;
261 
262 	desc_ring_size = droq->max_count * OCT_DROQ_DESC_SIZE;
263 	droq->desc_ring = lio_dma_alloc(oct, desc_ring_size,
264 					(dma_addr_t *)&droq->desc_ring_dma);
265 
266 	if (!droq->desc_ring) {
267 		dev_err(&oct->pci_dev->dev,
268 			"Output queue %d ring alloc failed\n", q_no);
269 		return 1;
270 	}
271 
272 	dev_dbg(&oct->pci_dev->dev, "droq[%d]: desc_ring: virt: 0x%p, dma: %lx\n",
273 		q_no, droq->desc_ring, droq->desc_ring_dma);
274 	dev_dbg(&oct->pci_dev->dev, "droq[%d]: num_desc: %d\n", q_no,
275 		droq->max_count);
276 
277 	droq->recv_buf_list = (struct octeon_recv_buffer *)
278 			      vmalloc_node(droq->max_count *
279 						OCT_DROQ_RECVBUF_SIZE,
280 						numa_node);
281 	if (!droq->recv_buf_list)
282 		droq->recv_buf_list = (struct octeon_recv_buffer *)
283 				      vmalloc(droq->max_count *
284 						OCT_DROQ_RECVBUF_SIZE);
285 	if (!droq->recv_buf_list) {
286 		dev_err(&oct->pci_dev->dev, "Output queue recv buf list alloc failed\n");
287 		goto init_droq_fail;
288 	}
289 
290 	if (octeon_droq_setup_ring_buffers(oct, droq))
291 		goto init_droq_fail;
292 
293 	droq->pkts_per_intr = c_pkts_per_intr;
294 	droq->refill_threshold = c_refill_threshold;
295 
296 	dev_dbg(&oct->pci_dev->dev, "DROQ INIT: max_empty_descs: %d\n",
297 		droq->max_empty_descs);
298 
299 	spin_lock_init(&droq->lock);
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  * Locks:
332  *  The droq->lock is held when this routine is called.
333  */
334 static inline struct octeon_recv_info *octeon_create_recv_info(
335 		struct octeon_device *octeon_dev,
336 		struct octeon_droq *droq,
337 		u32 buf_cnt,
338 		u32 idx)
339 {
340 	struct octeon_droq_info *info;
341 	struct octeon_recv_pkt *recv_pkt;
342 	struct octeon_recv_info *recv_info;
343 	u32 i, bytes_left;
344 	struct octeon_skb_page_info *pg_info;
345 
346 	info = (struct octeon_droq_info *)droq->recv_buf_list[idx].data;
347 
348 	recv_info = octeon_alloc_recv_info(sizeof(struct __dispatch));
349 	if (!recv_info)
350 		return NULL;
351 
352 	recv_pkt = recv_info->recv_pkt;
353 	recv_pkt->rh = info->rh;
354 	recv_pkt->length = (u32)info->length;
355 	recv_pkt->buffer_count = (u16)buf_cnt;
356 	recv_pkt->octeon_id = (u16)octeon_dev->octeon_id;
357 
358 	i = 0;
359 	bytes_left = (u32)info->length;
360 
361 	while (buf_cnt) {
362 		{
363 			pg_info = &droq->recv_buf_list[idx].pg_info;
364 
365 			lio_unmap_ring(octeon_dev->pci_dev,
366 				       (u64)pg_info->dma);
367 			pg_info->page = NULL;
368 			pg_info->dma = 0;
369 		}
370 
371 		recv_pkt->buffer_size[i] =
372 			(bytes_left >=
373 			 droq->buffer_size) ? droq->buffer_size : bytes_left;
374 
375 		recv_pkt->buffer_ptr[i] = droq->recv_buf_list[idx].buffer;
376 		droq->recv_buf_list[idx].buffer = NULL;
377 
378 		idx = incr_index(idx, 1, droq->max_count);
379 		bytes_left -= droq->buffer_size;
380 		i++;
381 		buf_cnt--;
382 	}
383 
384 	return recv_info;
385 }
386 
387 /* If we were not able to refill all buffers, try to move around
388  * the buffers that were not dispatched.
389  */
390 static inline u32
391 octeon_droq_refill_pullup_descs(struct octeon_droq *droq,
392 				struct octeon_droq_desc *desc_ring)
393 {
394 	u32 desc_refilled = 0;
395 
396 	u32 refill_index = droq->refill_idx;
397 
398 	while (refill_index != droq->read_idx) {
399 		if (droq->recv_buf_list[refill_index].buffer) {
400 			droq->recv_buf_list[droq->refill_idx].buffer =
401 				droq->recv_buf_list[refill_index].buffer;
402 			droq->recv_buf_list[droq->refill_idx].data =
403 				droq->recv_buf_list[refill_index].data;
404 			desc_ring[droq->refill_idx].buffer_ptr =
405 				desc_ring[refill_index].buffer_ptr;
406 			droq->recv_buf_list[refill_index].buffer = NULL;
407 			desc_ring[refill_index].buffer_ptr = 0;
408 			do {
409 				droq->refill_idx = incr_index(droq->refill_idx,
410 							      1,
411 							      droq->max_count);
412 				desc_refilled++;
413 				droq->refill_count--;
414 			} while (droq->recv_buf_list[droq->refill_idx].buffer);
415 		}
416 		refill_index = incr_index(refill_index, 1, droq->max_count);
417 	}                       /* while */
418 	return desc_refilled;
419 }
420 
421 /* octeon_droq_refill
422  * Parameters:
423  *  droq       - droq in which descriptors require new buffers.
424  * Description:
425  *  Called during normal DROQ processing in interrupt mode or by the poll
426  *  thread to refill the descriptors from which buffers were dispatched
427  *  to upper layers. Attempts to allocate new buffers. If that fails, moves
428  *  up buffers (that were not dispatched) to form a contiguous ring.
429  * Returns:
430  *  No of descriptors refilled.
431  * Locks:
432  *  This routine is called with droq->lock held.
433  */
434 static u32
435 octeon_droq_refill(struct octeon_device *octeon_dev, struct octeon_droq *droq)
436 {
437 	struct octeon_droq_desc *desc_ring;
438 	void *buf = NULL;
439 	u8 *data;
440 	u32 desc_refilled = 0;
441 	struct octeon_skb_page_info *pg_info;
442 
443 	desc_ring = droq->desc_ring;
444 
445 	while (droq->refill_count && (desc_refilled < droq->max_count)) {
446 		/* If a valid buffer exists (happens if there is no dispatch),
447 		 * reuse
448 		 * the buffer, else allocate.
449 		 */
450 		if (!droq->recv_buf_list[droq->refill_idx].buffer) {
451 			pg_info =
452 				&droq->recv_buf_list[droq->refill_idx].pg_info;
453 			/* Either recycle the existing pages or go for
454 			 * new page alloc
455 			 */
456 			if (pg_info->page)
457 				buf = recv_buffer_reuse(octeon_dev, pg_info);
458 			else
459 				buf = recv_buffer_alloc(octeon_dev, pg_info);
460 			/* If a buffer could not be allocated, no point in
461 			 * continuing
462 			 */
463 			if (!buf) {
464 				droq->stats.rx_alloc_failure++;
465 				break;
466 			}
467 			droq->recv_buf_list[droq->refill_idx].buffer =
468 				buf;
469 			data = get_rbd(buf);
470 		} else {
471 			data = get_rbd(droq->recv_buf_list
472 				       [droq->refill_idx].buffer);
473 		}
474 
475 		droq->recv_buf_list[droq->refill_idx].data = data;
476 
477 		desc_ring[droq->refill_idx].buffer_ptr =
478 			lio_map_ring(droq->recv_buf_list[
479 				     droq->refill_idx].buffer);
480 
481 		droq->refill_idx = incr_index(droq->refill_idx, 1,
482 					      droq->max_count);
483 		desc_refilled++;
484 		droq->refill_count--;
485 	}
486 
487 	if (droq->refill_count)
488 		desc_refilled +=
489 			octeon_droq_refill_pullup_descs(droq, desc_ring);
490 
491 	/* if droq->refill_count
492 	 * The refill count would not change in pass two. We only moved buffers
493 	 * to close the gap in the ring, but we would still have the same no. of
494 	 * buffers to refill.
495 	 */
496 	return desc_refilled;
497 }
498 
499 /** check if we can allocate packets to get out of oom.
500  *  @param  droq - Droq being checked.
501  *  @return does not return anything
502  */
503 void octeon_droq_check_oom(struct octeon_droq *droq)
504 {
505 	int desc_refilled;
506 	struct octeon_device *oct = droq->oct_dev;
507 
508 	if (readl(droq->pkts_credit_reg) <= CN23XX_SLI_DEF_BP) {
509 		spin_lock_bh(&droq->lock);
510 		desc_refilled = octeon_droq_refill(oct, droq);
511 		if (desc_refilled) {
512 			/* Flush the droq descriptor data to memory to be sure
513 			 * that when we update the credits the data in memory
514 			 * is accurate.
515 			 */
516 			wmb();
517 			writel(desc_refilled, droq->pkts_credit_reg);
518 			/* make sure mmio write completes */
519 			mmiowb();
520 		}
521 		spin_unlock_bh(&droq->lock);
522 	}
523 }
524 
525 static inline u32
526 octeon_droq_get_bufcount(u32 buf_size, u32 total_len)
527 {
528 	return ((total_len + buf_size - 1) / buf_size);
529 }
530 
531 static int
532 octeon_droq_dispatch_pkt(struct octeon_device *oct,
533 			 struct octeon_droq *droq,
534 			 union octeon_rh *rh,
535 			 struct octeon_droq_info *info)
536 {
537 	u32 cnt;
538 	octeon_dispatch_fn_t disp_fn;
539 	struct octeon_recv_info *rinfo;
540 
541 	cnt = octeon_droq_get_bufcount(droq->buffer_size, (u32)info->length);
542 
543 	disp_fn = octeon_get_dispatch(oct, (u16)rh->r.opcode,
544 				      (u16)rh->r.subcode);
545 	if (disp_fn) {
546 		rinfo = octeon_create_recv_info(oct, droq, cnt, droq->read_idx);
547 		if (rinfo) {
548 			struct __dispatch *rdisp = rinfo->rsvd;
549 
550 			rdisp->rinfo = rinfo;
551 			rdisp->disp_fn = disp_fn;
552 			rinfo->recv_pkt->rh = *rh;
553 			list_add_tail(&rdisp->list,
554 				      &droq->dispatch_list);
555 		} else {
556 			droq->stats.dropped_nomem++;
557 		}
558 	} else {
559 		dev_err(&oct->pci_dev->dev, "DROQ: No dispatch function (opcode %u/%u)\n",
560 			(unsigned int)rh->r.opcode,
561 			(unsigned int)rh->r.subcode);
562 		droq->stats.dropped_nodispatch++;
563 	}
564 
565 	return cnt;
566 }
567 
568 static inline void octeon_droq_drop_packets(struct octeon_device *oct,
569 					    struct octeon_droq *droq,
570 					    u32 cnt)
571 {
572 	u32 i = 0, buf_cnt;
573 	struct octeon_droq_info *info;
574 
575 	for (i = 0; i < cnt; i++) {
576 		info = (struct octeon_droq_info *)
577 			droq->recv_buf_list[droq->read_idx].data;
578 		octeon_swap_8B_data((u64 *)info, 2);
579 
580 		if (info->length) {
581 			info->length += OCTNET_FRM_LENGTH_SIZE;
582 			droq->stats.bytes_received += info->length;
583 			buf_cnt = octeon_droq_get_bufcount(droq->buffer_size,
584 							   (u32)info->length);
585 		} else {
586 			dev_err(&oct->pci_dev->dev, "DROQ: In drop: pkt with len 0\n");
587 			buf_cnt = 1;
588 		}
589 
590 		droq->read_idx = incr_index(droq->read_idx, buf_cnt,
591 					    droq->max_count);
592 		droq->refill_count += buf_cnt;
593 	}
594 }
595 
596 static u32
597 octeon_droq_fast_process_packets(struct octeon_device *oct,
598 				 struct octeon_droq *droq,
599 				 u32 pkts_to_process)
600 {
601 	struct octeon_droq_info *info;
602 	union octeon_rh *rh;
603 	u32 pkt, total_len = 0, pkt_count;
604 
605 	pkt_count = pkts_to_process;
606 
607 	for (pkt = 0; pkt < pkt_count; pkt++) {
608 		u32 pkt_len = 0;
609 		struct sk_buff *nicbuf = NULL;
610 		struct octeon_skb_page_info *pg_info;
611 		void *buf;
612 
613 		info = (struct octeon_droq_info *)
614 			droq->recv_buf_list[droq->read_idx].data;
615 		octeon_swap_8B_data((u64 *)info, 2);
616 
617 		if (!info->length) {
618 			dev_err(&oct->pci_dev->dev,
619 				"DROQ[%d] idx: %d len:0, pkt_cnt: %d\n",
620 				droq->q_no, droq->read_idx, pkt_count);
621 			print_hex_dump_bytes("", DUMP_PREFIX_ADDRESS,
622 					     (u8 *)info,
623 					     OCT_DROQ_INFO_SIZE);
624 			break;
625 		}
626 
627 		/* Len of resp hdr in included in the received data len. */
628 		rh = &info->rh;
629 
630 		info->length += OCTNET_FRM_LENGTH_SIZE;
631 		rh->r_dh.len += (ROUNDUP8(OCT_DROQ_INFO_SIZE) / sizeof(u64));
632 		total_len += (u32)info->length;
633 		if (opcode_slow_path(rh)) {
634 			u32 buf_cnt;
635 
636 			buf_cnt = octeon_droq_dispatch_pkt(oct, droq, rh, info);
637 			droq->read_idx = incr_index(droq->read_idx,
638 						    buf_cnt, droq->max_count);
639 			droq->refill_count += buf_cnt;
640 		} else {
641 			if (info->length <= droq->buffer_size) {
642 				pkt_len = (u32)info->length;
643 				nicbuf = droq->recv_buf_list[
644 					droq->read_idx].buffer;
645 				pg_info = &droq->recv_buf_list[
646 					droq->read_idx].pg_info;
647 				if (recv_buffer_recycle(oct, pg_info))
648 					pg_info->page = NULL;
649 				droq->recv_buf_list[droq->read_idx].buffer =
650 					NULL;
651 
652 				droq->read_idx = incr_index(droq->read_idx, 1,
653 							    droq->max_count);
654 				droq->refill_count++;
655 			} else {
656 				nicbuf = octeon_fast_packet_alloc((u32)
657 								  info->length);
658 				pkt_len = 0;
659 				/* nicbuf allocation can fail. We'll handle it
660 				 * inside the loop.
661 				 */
662 				while (pkt_len < info->length) {
663 					int cpy_len, idx = droq->read_idx;
664 
665 					cpy_len = ((pkt_len + droq->buffer_size)
666 						   > info->length) ?
667 						((u32)info->length - pkt_len) :
668 						droq->buffer_size;
669 
670 					if (nicbuf) {
671 						octeon_fast_packet_next(droq,
672 									nicbuf,
673 									cpy_len,
674 									idx);
675 						buf = droq->recv_buf_list[
676 							idx].buffer;
677 						recv_buffer_fast_free(buf);
678 						droq->recv_buf_list[idx].buffer
679 							= NULL;
680 					} else {
681 						droq->stats.rx_alloc_failure++;
682 					}
683 
684 					pkt_len += cpy_len;
685 					droq->read_idx =
686 						incr_index(droq->read_idx, 1,
687 							   droq->max_count);
688 					droq->refill_count++;
689 				}
690 			}
691 
692 			if (nicbuf) {
693 				if (droq->ops.fptr) {
694 					droq->ops.fptr(oct->octeon_id,
695 						       nicbuf, pkt_len,
696 						       rh, &droq->napi,
697 						       droq->ops.farg);
698 				} else {
699 					recv_buffer_free(nicbuf);
700 				}
701 			}
702 		}
703 
704 		if (droq->refill_count >= droq->refill_threshold) {
705 			int desc_refilled = octeon_droq_refill(oct, droq);
706 
707 			/* Flush the droq descriptor data to memory to be sure
708 			 * that when we update the credits the data in memory
709 			 * is accurate.
710 			 */
711 			wmb();
712 			writel((desc_refilled), droq->pkts_credit_reg);
713 			/* make sure mmio write completes */
714 			mmiowb();
715 		}
716 
717 	}                       /* for (each packet)... */
718 
719 	/* Increment refill_count by the number of buffers processed. */
720 	droq->stats.pkts_received += pkt;
721 	droq->stats.bytes_received += total_len;
722 
723 	if ((droq->ops.drop_on_max) && (pkts_to_process - pkt)) {
724 		octeon_droq_drop_packets(oct, droq, (pkts_to_process - pkt));
725 
726 		droq->stats.dropped_toomany += (pkts_to_process - pkt);
727 		return pkts_to_process;
728 	}
729 
730 	return pkt;
731 }
732 
733 int
734 octeon_droq_process_packets(struct octeon_device *oct,
735 			    struct octeon_droq *droq,
736 			    u32 budget)
737 {
738 	u32 pkt_count = 0, pkts_processed = 0;
739 	struct list_head *tmp, *tmp2;
740 
741 	/* Grab the droq lock */
742 	spin_lock(&droq->lock);
743 
744 	octeon_droq_check_hw_for_pkts(droq);
745 	pkt_count = atomic_read(&droq->pkts_pending);
746 
747 	if (!pkt_count) {
748 		spin_unlock(&droq->lock);
749 		return 0;
750 	}
751 
752 	if (pkt_count > budget)
753 		pkt_count = budget;
754 
755 	pkts_processed = octeon_droq_fast_process_packets(oct, droq, pkt_count);
756 
757 	atomic_sub(pkts_processed, &droq->pkts_pending);
758 
759 	/* Release the spin lock */
760 	spin_unlock(&droq->lock);
761 
762 	list_for_each_safe(tmp, tmp2, &droq->dispatch_list) {
763 		struct __dispatch *rdisp = (struct __dispatch *)tmp;
764 
765 		list_del(tmp);
766 		rdisp->disp_fn(rdisp->rinfo,
767 			       octeon_get_dispatch_arg
768 			       (oct,
769 				(u16)rdisp->rinfo->recv_pkt->rh.r.opcode,
770 				(u16)rdisp->rinfo->recv_pkt->rh.r.subcode));
771 	}
772 
773 	/* If there are packets pending. schedule tasklet again */
774 	if (atomic_read(&droq->pkts_pending))
775 		return 1;
776 
777 	return 0;
778 }
779 
780 /**
781  * Utility function to poll for packets. check_hw_for_packets must be
782  * called before calling this routine.
783  */
784 
785 static int
786 octeon_droq_process_poll_pkts(struct octeon_device *oct,
787 			      struct octeon_droq *droq, u32 budget)
788 {
789 	struct list_head *tmp, *tmp2;
790 	u32 pkts_available = 0, pkts_processed = 0;
791 	u32 total_pkts_processed = 0;
792 
793 	if (budget > droq->max_count)
794 		budget = droq->max_count;
795 
796 	spin_lock(&droq->lock);
797 
798 	while (total_pkts_processed < budget) {
799 		octeon_droq_check_hw_for_pkts(droq);
800 
801 		pkts_available = min((budget - total_pkts_processed),
802 				     (u32)(atomic_read(&droq->pkts_pending)));
803 
804 		if (pkts_available == 0)
805 			break;
806 
807 		pkts_processed =
808 			octeon_droq_fast_process_packets(oct, droq,
809 							 pkts_available);
810 
811 		atomic_sub(pkts_processed, &droq->pkts_pending);
812 
813 		total_pkts_processed += pkts_processed;
814 	}
815 
816 	spin_unlock(&droq->lock);
817 
818 	list_for_each_safe(tmp, tmp2, &droq->dispatch_list) {
819 		struct __dispatch *rdisp = (struct __dispatch *)tmp;
820 
821 		list_del(tmp);
822 		rdisp->disp_fn(rdisp->rinfo,
823 			       octeon_get_dispatch_arg
824 			       (oct,
825 				(u16)rdisp->rinfo->recv_pkt->rh.r.opcode,
826 				(u16)rdisp->rinfo->recv_pkt->rh.r.subcode));
827 	}
828 
829 	return total_pkts_processed;
830 }
831 
832 int
833 octeon_process_droq_poll_cmd(struct octeon_device *oct, u32 q_no, int cmd,
834 			     u32 arg)
835 {
836 	struct octeon_droq *droq;
837 
838 	droq = oct->droq[q_no];
839 
840 	if (cmd == POLL_EVENT_PROCESS_PKTS)
841 		return octeon_droq_process_poll_pkts(oct, droq, arg);
842 
843 	if (cmd == POLL_EVENT_PENDING_PKTS) {
844 		u32 pkt_cnt = atomic_read(&droq->pkts_pending);
845 
846 		return  octeon_droq_process_packets(oct, droq, pkt_cnt);
847 	}
848 
849 	if (cmd == POLL_EVENT_ENABLE_INTR) {
850 		u32 value;
851 		unsigned long flags;
852 
853 		/* Enable Pkt Interrupt */
854 		switch (oct->chip_id) {
855 		case OCTEON_CN66XX:
856 		case OCTEON_CN68XX: {
857 			struct octeon_cn6xxx *cn6xxx =
858 				(struct octeon_cn6xxx *)oct->chip;
859 			spin_lock_irqsave
860 				(&cn6xxx->lock_for_droq_int_enb_reg, flags);
861 			value =
862 				octeon_read_csr(oct,
863 						CN6XXX_SLI_PKT_TIME_INT_ENB);
864 			value |= (1 << q_no);
865 			octeon_write_csr(oct,
866 					 CN6XXX_SLI_PKT_TIME_INT_ENB,
867 					 value);
868 			value =
869 				octeon_read_csr(oct,
870 						CN6XXX_SLI_PKT_CNT_INT_ENB);
871 			value |= (1 << q_no);
872 			octeon_write_csr(oct,
873 					 CN6XXX_SLI_PKT_CNT_INT_ENB,
874 					 value);
875 
876 			/* don't bother flushing the enables */
877 
878 			spin_unlock_irqrestore
879 				(&cn6xxx->lock_for_droq_int_enb_reg, flags);
880 			return 0;
881 		}
882 		break;
883 		case OCTEON_CN23XX_PF_VID: {
884 			lio_enable_irq(oct->droq[q_no], oct->instr_queue[q_no]);
885 		}
886 		break;
887 
888 		case OCTEON_CN23XX_VF_VID:
889 			lio_enable_irq(oct->droq[q_no], oct->instr_queue[q_no]);
890 		break;
891 		}
892 		return 0;
893 	}
894 
895 	dev_err(&oct->pci_dev->dev, "%s Unknown command: %d\n", __func__, cmd);
896 	return -EINVAL;
897 }
898 
899 int octeon_register_droq_ops(struct octeon_device *oct, u32 q_no,
900 			     struct octeon_droq_ops *ops)
901 {
902 	struct octeon_droq *droq;
903 	unsigned long flags;
904 	struct octeon_config *oct_cfg = NULL;
905 
906 	oct_cfg = octeon_get_conf(oct);
907 
908 	if (!oct_cfg)
909 		return -EINVAL;
910 
911 	if (!(ops)) {
912 		dev_err(&oct->pci_dev->dev, "%s: droq_ops pointer is NULL\n",
913 			__func__);
914 		return -EINVAL;
915 	}
916 
917 	if (q_no >= CFG_GET_OQ_MAX_Q(oct_cfg)) {
918 		dev_err(&oct->pci_dev->dev, "%s: droq id (%d) exceeds MAX (%d)\n",
919 			__func__, q_no, (oct->num_oqs - 1));
920 		return -EINVAL;
921 	}
922 
923 	droq = oct->droq[q_no];
924 
925 	spin_lock_irqsave(&droq->lock, flags);
926 
927 	memcpy(&droq->ops, ops, sizeof(struct octeon_droq_ops));
928 
929 	spin_unlock_irqrestore(&droq->lock, flags);
930 
931 	return 0;
932 }
933 
934 int octeon_unregister_droq_ops(struct octeon_device *oct, u32 q_no)
935 {
936 	unsigned long flags;
937 	struct octeon_droq *droq;
938 	struct octeon_config *oct_cfg = NULL;
939 
940 	oct_cfg = octeon_get_conf(oct);
941 
942 	if (!oct_cfg)
943 		return -EINVAL;
944 
945 	if (q_no >= CFG_GET_OQ_MAX_Q(oct_cfg)) {
946 		dev_err(&oct->pci_dev->dev, "%s: droq id (%d) exceeds MAX (%d)\n",
947 			__func__, q_no, oct->num_oqs - 1);
948 		return -EINVAL;
949 	}
950 
951 	droq = oct->droq[q_no];
952 
953 	if (!droq) {
954 		dev_info(&oct->pci_dev->dev,
955 			 "Droq id (%d) not available.\n", q_no);
956 		return 0;
957 	}
958 
959 	spin_lock_irqsave(&droq->lock, flags);
960 
961 	droq->ops.fptr = NULL;
962 	droq->ops.farg = NULL;
963 	droq->ops.drop_on_max = 0;
964 
965 	spin_unlock_irqrestore(&droq->lock, flags);
966 
967 	return 0;
968 }
969 
970 int octeon_create_droq(struct octeon_device *oct,
971 		       u32 q_no, u32 num_descs,
972 		       u32 desc_size, void *app_ctx)
973 {
974 	struct octeon_droq *droq;
975 	int numa_node = dev_to_node(&oct->pci_dev->dev);
976 
977 	if (oct->droq[q_no]) {
978 		dev_dbg(&oct->pci_dev->dev, "Droq already in use. Cannot create droq %d again\n",
979 			q_no);
980 		return 1;
981 	}
982 
983 	/* Allocate the DS for the new droq. */
984 	droq = vmalloc_node(sizeof(*droq), numa_node);
985 	if (!droq)
986 		droq = vmalloc(sizeof(*droq));
987 	if (!droq)
988 		return -1;
989 
990 	memset(droq, 0, sizeof(struct octeon_droq));
991 
992 	/*Disable the pkt o/p for this Q  */
993 	octeon_set_droq_pkt_op(oct, q_no, 0);
994 	oct->droq[q_no] = droq;
995 
996 	/* Initialize the Droq */
997 	if (octeon_init_droq(oct, q_no, num_descs, desc_size, app_ctx)) {
998 		vfree(oct->droq[q_no]);
999 		oct->droq[q_no] = NULL;
1000 		return -1;
1001 	}
1002 
1003 	oct->num_oqs++;
1004 
1005 	dev_dbg(&oct->pci_dev->dev, "%s: Total number of OQ: %d\n", __func__,
1006 		oct->num_oqs);
1007 
1008 	/* Global Droq register settings */
1009 
1010 	/* As of now not required, as setting are done for all 32 Droqs at
1011 	 * the same time.
1012 	 */
1013 	return 0;
1014 }
1015