xref: /OK3568_Linux_fs/external/rkwifibt/drivers/infineon/include/bcm_ring.h (revision 4882a59341e53eb6f0b4789bf948001014eff981)
1 /*
2  * bcm_ring.h : Ring context abstraction
3  * The ring context tracks the WRITE and READ indices where elements may be
4  * produced and consumed respectively. All elements in the ring need to be
5  * fixed size.
6  *
7  * NOTE: A ring of size N, may only hold N-1 elements.
8  *
9  * Portions of this code are copyright (c) 2021 Cypress Semiconductor Corporation
10  *
11  * Copyright (C) 1999-2017, Broadcom Corporation
12  *
13  *      Unless you and Broadcom execute a separate written software license
14  * agreement governing use of this software, this software is licensed to you
15  * under the terms of the GNU General Public License version 2 (the "GPL"),
16  * available at http://www.broadcom.com/licenses/GPLv2.php, with the
17  * following added to such license:
18  *
19  *      As a special exception, the copyright holders of this software give you
20  * permission to link this software with independent modules, and to copy and
21  * distribute the resulting executable under terms of your choice, provided that
22  * you also meet, for each linked independent module, the terms and conditions of
23  * the license of that module.  An independent module is a module which is not
24  * derived from this software.  The special exception does not apply to any
25  * modifications of the software.
26  *
27  *      Notwithstanding the above, under no circumstances may you combine this
28  * software in any way with any other Broadcom software provided under a license
29  * other than the GPL, without Broadcom's express prior written consent.
30  *
31  *
32  * <<Broadcom-WL-IPTag/Open:>>
33  *
34  * $Id: bcm_ring.h 700321 2017-05-18 16:09:07Z $
35  */
36 #ifndef __bcm_ring_included__
37 #define __bcm_ring_included__
38 /*
39  * API Notes:
40  *
41  * Ring manipulation API allows for:
42  *  Pending operations: Often before some work can be completed, it may be
43  *  desired that several resources are available, e.g. space for production in
44  *  a ring. Approaches such as, #1) reserve resources one by one and return them
45  *  if another required resource is not available, or #2) employ a two pass
46  *  algorithm of first testing whether all resources are available, have a
47  *  an impact on performance critical code. The approach taken here is more akin
48  *  to approach #2, where a test for resource availability essentially also
49  *  provides the index for production in an un-committed state.
50  *  The same approach is taken for the consumer side.
51  *
52  *  - Pending production: Fetch the next index where a ring element may be
53  *    produced. The caller may not commit the WRITE of the element.
54  *  - Pending consumption: Fetch the next index where a ring element may be
55  *    consumed. The caller may not commut the READ of the element.
56  *
57  *  Producer side API:
58  *  - bcm_ring_is_full  : Test whether ring is full
59  *  - bcm_ring_prod     : Fetch index where an element may be produced (commit)
60  *  - bcm_ring_prod_pend: Fetch index where an element may be produced (pending)
61  *  - bcm_ring_prod_done: Commit a previous pending produce fetch
62  *  - bcm_ring_prod_avail: Fetch total number free slots eligible for production
63  *
64  * Consumer side API:
65  *  - bcm_ring_is_empty : Test whether ring is empty
66  *  - bcm_ring_cons     : Fetch index where an element may be consumed (commit)
67  *  - bcm_ring_cons_pend: Fetch index where an element may be consumed (pending)
68  *  - bcm_ring_cons_done: Commit a previous pending consume fetch
69  *  - bcm_ring_cons_avail: Fetch total number elements eligible for consumption
70  *
71  *  - bcm_ring_sync_read: Sync read offset in peer ring, from local ring
72  *  - bcm_ring_sync_write: Sync write offset in peer ring, from local ring
73  *
74  * +----------------------------------------------------------------------------
75  *
76  * Design Notes:
77  * Following items are not tracked in a ring context (design decision)
78  *  - width of a ring element.
79  *  - depth of the ring.
80  *  - base of the buffer, where the elements are stored.
81  *  - count of number of free slots in the ring
82  *
83  * Implementation Notes:
84  *  - When BCM_RING_DEBUG is enabled, need explicit bcm_ring_init().
85  *  - BCM_RING_EMPTY and BCM_RING_FULL are (-1)
86  *
87  * +----------------------------------------------------------------------------
88  *
89  * Usage Notes:
90  * An application may incarnate a ring of some fixed sized elements, by defining
91  *  - a ring data buffer to store the ring elements.
92  *  - depth of the ring (max number of elements managed by ring context).
93  *    Preferrably, depth may be represented as a constant.
94  *  - width of a ring element: to be used in pointer arithmetic with the ring's
95  *    data buffer base and an index to fetch the ring element.
96  *
97  * Use bcm_workq_t to instantiate a pair of workq constructs, one for the
98  * producer and the other for the consumer, both pointing to the same circular
99  * buffer. The producer may operate on it's own local workq and flush the write
100  * index to the consumer. Likewise the consumer may use its local workq and
101  * flush the read index to the producer. This way we do not repeatedly access
102  * the peer's context. The two peers may reside on different CPU cores with a
103  * private L1 data cache.
104  * +----------------------------------------------------------------------------
105  *
106  * Portions of this code are copyright (c) 2021 Cypress Semiconductor Corporation
107  *
108  * Copyright (C) 1999-2017, Broadcom Corporation
109  *
110  *      Unless you and Broadcom execute a separate written software license
111  * agreement governing use of this software, this software is licensed to you
112  * under the terms of the GNU General Public License version 2 (the "GPL"),
113  * available at http://www.broadcom.com/licenses/GPLv2.php, with the
114  * following added to such license:
115  *
116  *      As a special exception, the copyright holders of this software give you
117  * permission to link this software with independent modules, and to copy and
118  * distribute the resulting executable under terms of your choice, provided that
119  * you also meet, for each linked independent module, the terms and conditions of
120  * the license of that module.  An independent module is a module which is not
121  * derived from this software.  The special exception does not apply to any
122  * modifications of the software.
123  *
124  *      Notwithstanding the above, under no circumstances may you combine this
125  * software in any way with any other Broadcom software provided under a license
126  * other than the GPL, without Broadcom's express prior written consent.
127  *
128  * $Id: bcm_ring.h 700321 2017-05-18 16:09:07Z $
129  *
130  * -*- Mode: C; tab-width: 4; indent-tabs-mode: t; c-basic-offset: 4 -*-
131  * vim: set ts=4 noet sw=4 tw=80:
132  *
133  * +----------------------------------------------------------------------------
134  */
135 
136 #ifdef ____cacheline_aligned
137 #define __ring_aligned                      ____cacheline_aligned
138 #else
139 #define __ring_aligned
140 #endif // endif
141 
142 /* Conditional compile for debug */
143 /* #define BCM_RING_DEBUG */
144 
145 #define BCM_RING_EMPTY                      (-1)
146 #define BCM_RING_FULL                       (-1)
147 #define BCM_RING_NULL                       ((bcm_ring_t *)NULL)
148 
149 #if defined(BCM_RING_DEBUG)
150 #define RING_ASSERT(exp)                    ASSERT(exp)
151 #define BCM_RING_IS_VALID(ring)             (((ring) != BCM_RING_NULL) && \
152 	                                         ((ring)->self == (ring)))
153 #else  /* ! BCM_RING_DEBUG */
154 #define RING_ASSERT(exp)                    do {} while (0)
155 #define BCM_RING_IS_VALID(ring)             ((ring) != BCM_RING_NULL)
156 #endif /* ! BCM_RING_DEBUG */
157 
158 #define BCM_RING_SIZE_IS_VALID(ring_size)   ((ring_size) > 0)
159 
160 /*
161  * +----------------------------------------------------------------------------
162  * Ring Context
163  * +----------------------------------------------------------------------------
164  */
165 typedef struct bcm_ring {     /* Ring context */
166 #if defined(BCM_RING_DEBUG)
167 	struct bcm_ring *self;    /* ptr to self for IS VALID test */
168 #endif /* BCM_RING_DEBUG */
169 	int write __ring_aligned; /* WRITE index in a circular ring */
170 	int read  __ring_aligned; /* READ index in a circular ring */
171 } bcm_ring_t;
172 
173 static INLINE void bcm_ring_init(bcm_ring_t *ring);
174 static INLINE void bcm_ring_copy(bcm_ring_t *to, bcm_ring_t *from);
175 static INLINE bool bcm_ring_is_empty(bcm_ring_t *ring);
176 
177 static INLINE int  __bcm_ring_next_write(bcm_ring_t *ring, const int ring_size);
178 
179 static INLINE bool __bcm_ring_full(bcm_ring_t *ring, int next_write);
180 static INLINE bool bcm_ring_is_full(bcm_ring_t *ring, const int ring_size);
181 
182 static INLINE void bcm_ring_prod_done(bcm_ring_t *ring, int write);
183 static INLINE int  bcm_ring_prod_pend(bcm_ring_t *ring, int *pend_write,
184                                       const int ring_size);
185 static INLINE int  bcm_ring_prod(bcm_ring_t *ring, const int ring_size);
186 
187 static INLINE void bcm_ring_cons_done(bcm_ring_t *ring, int read);
188 static INLINE int  bcm_ring_cons_pend(bcm_ring_t *ring, int *pend_read,
189                                       const int ring_size);
190 static INLINE int  bcm_ring_cons(bcm_ring_t *ring, const int ring_size);
191 
192 static INLINE void bcm_ring_sync_read(bcm_ring_t *peer, const bcm_ring_t *self);
193 static INLINE void bcm_ring_sync_write(bcm_ring_t *peer, const bcm_ring_t *self);
194 
195 static INLINE int  bcm_ring_prod_avail(const bcm_ring_t *ring,
196                                        const int ring_size);
197 static INLINE int  bcm_ring_cons_avail(const bcm_ring_t *ring,
198                                        const int ring_size);
199 static INLINE void bcm_ring_cons_all(bcm_ring_t *ring);
200 
201 /**
202  * bcm_ring_init - initialize a ring context.
203  * @ring: pointer to a ring context
204  */
205 static INLINE void
bcm_ring_init(bcm_ring_t * ring)206 bcm_ring_init(bcm_ring_t *ring)
207 {
208 	ASSERT(ring != (bcm_ring_t *)NULL);
209 #if defined(BCM_RING_DEBUG)
210 	ring->self = ring;
211 #endif /* BCM_RING_DEBUG */
212 	ring->write = 0;
213 	ring->read = 0;
214 }
215 
216 /**
217  * bcm_ring_copy - copy construct a ring
218  * @to: pointer to the new ring context
219  * @from: pointer to orig ring context
220  */
221 static INLINE void
bcm_ring_copy(bcm_ring_t * to,bcm_ring_t * from)222 bcm_ring_copy(bcm_ring_t *to, bcm_ring_t *from)
223 {
224 	bcm_ring_init(to);
225 
226 	to->write = from->write;
227 	to->read  = from->read;
228 }
229 
230 /**
231  * bcm_ring_is_empty - "Boolean" test whether ring is empty.
232  * @ring: pointer to a ring context
233  *
234  * PS. does not return BCM_RING_EMPTY value.
235  */
236 static INLINE bool
bcm_ring_is_empty(bcm_ring_t * ring)237 bcm_ring_is_empty(bcm_ring_t *ring)
238 {
239 	RING_ASSERT(BCM_RING_IS_VALID(ring));
240 	return (ring->read == ring->write);
241 }
242 
243 /**
244  * __bcm_ring_next_write - determine the index where the next write may occur
245  *                         (with wrap-around).
246  * @ring: pointer to a ring context
247  * @ring_size: size of the ring
248  *
249  * PRIVATE INTERNAL USE ONLY.
250  */
251 static INLINE int
__bcm_ring_next_write(bcm_ring_t * ring,const int ring_size)252 __bcm_ring_next_write(bcm_ring_t *ring, const int ring_size)
253 {
254 	RING_ASSERT(BCM_RING_IS_VALID(ring) && BCM_RING_SIZE_IS_VALID(ring_size));
255 	return ((ring->write + 1) % ring_size);
256 }
257 
258 /**
259  * __bcm_ring_full - support function for ring full test.
260  * @ring: pointer to a ring context
261  * @next_write: next location in ring where an element is to be produced
262  *
263  * PRIVATE INTERNAL USE ONLY.
264  */
265 static INLINE bool
__bcm_ring_full(bcm_ring_t * ring,int next_write)266 __bcm_ring_full(bcm_ring_t *ring, int next_write)
267 {
268 	return (next_write == ring->read);
269 }
270 
271 /**
272  * bcm_ring_is_full - "Boolean" test whether a ring is full.
273  * @ring: pointer to a ring context
274  * @ring_size: size of the ring
275  *
276  * PS. does not return BCM_RING_FULL value.
277  */
278 static INLINE bool
bcm_ring_is_full(bcm_ring_t * ring,const int ring_size)279 bcm_ring_is_full(bcm_ring_t *ring, const int ring_size)
280 {
281 	int next_write;
282 	RING_ASSERT(BCM_RING_IS_VALID(ring) && BCM_RING_SIZE_IS_VALID(ring_size));
283 	next_write = __bcm_ring_next_write(ring, ring_size);
284 	return __bcm_ring_full(ring, next_write);
285 }
286 
287 /**
288  * bcm_ring_prod_done - commit a previously pending index where production
289  * was requested.
290  * @ring: pointer to a ring context
291  * @write: index into ring upto where production was done.
292  * +----------------------------------------------------------------------------
293  */
294 static INLINE void
bcm_ring_prod_done(bcm_ring_t * ring,int write)295 bcm_ring_prod_done(bcm_ring_t *ring, int write)
296 {
297 	RING_ASSERT(BCM_RING_IS_VALID(ring));
298 	ring->write = write;
299 }
300 
301 /**
302  * bcm_ring_prod_pend - Fetch in "pend" mode, the index where an element may be
303  * produced.
304  * @ring: pointer to a ring context
305  * @pend_write: next index, after the returned index
306  * @ring_size: size of the ring
307  */
308 static INLINE int
bcm_ring_prod_pend(bcm_ring_t * ring,int * pend_write,const int ring_size)309 bcm_ring_prod_pend(bcm_ring_t *ring, int *pend_write, const int ring_size)
310 {
311 	int rtn;
312 	RING_ASSERT(BCM_RING_IS_VALID(ring) && BCM_RING_SIZE_IS_VALID(ring_size));
313 	*pend_write = __bcm_ring_next_write(ring, ring_size);
314 	if (__bcm_ring_full(ring, *pend_write)) {
315 		*pend_write = BCM_RING_FULL;
316 		rtn = BCM_RING_FULL;
317 	} else {
318 		/* production is not committed, caller needs to explicitly commit */
319 		rtn = ring->write;
320 	}
321 	return rtn;
322 }
323 
324 /**
325  * bcm_ring_prod - Fetch and "commit" the next index where a ring element may
326  * be produced.
327  * @ring: pointer to a ring context
328  * @ring_size: size of the ring
329  */
330 static INLINE int
bcm_ring_prod(bcm_ring_t * ring,const int ring_size)331 bcm_ring_prod(bcm_ring_t *ring, const int ring_size)
332 {
333 	int next_write, prod_write;
334 	RING_ASSERT(BCM_RING_IS_VALID(ring) && BCM_RING_SIZE_IS_VALID(ring_size));
335 
336 	next_write = __bcm_ring_next_write(ring, ring_size);
337 	if (__bcm_ring_full(ring, next_write)) {
338 		prod_write = BCM_RING_FULL;
339 	} else {
340 		prod_write = ring->write;
341 		bcm_ring_prod_done(ring, next_write); /* "commit" production */
342 	}
343 	return prod_write;
344 }
345 
346 /**
347  * bcm_ring_cons_done - commit a previously pending read
348  * @ring: pointer to a ring context
349  * @read: index upto which elements have been consumed.
350  */
351 static INLINE void
bcm_ring_cons_done(bcm_ring_t * ring,int read)352 bcm_ring_cons_done(bcm_ring_t *ring, int read)
353 {
354 	RING_ASSERT(BCM_RING_IS_VALID(ring));
355 	ring->read = read;
356 }
357 
358 /**
359  * bcm_ring_cons_pend - fetch in "pend" mode, the next index where a ring
360  * element may be consumed.
361  * @ring: pointer to a ring context
362  * @pend_read: index into ring upto which elements may be consumed.
363  * @ring_size: size of the ring
364  */
365 static INLINE int
bcm_ring_cons_pend(bcm_ring_t * ring,int * pend_read,const int ring_size)366 bcm_ring_cons_pend(bcm_ring_t *ring, int *pend_read, const int ring_size)
367 {
368 	int rtn;
369 	RING_ASSERT(BCM_RING_IS_VALID(ring) && BCM_RING_SIZE_IS_VALID(ring_size));
370 	if (bcm_ring_is_empty(ring)) {
371 		*pend_read = BCM_RING_EMPTY;
372 		rtn = BCM_RING_EMPTY;
373 	} else {
374 		*pend_read = (ring->read + 1) % ring_size;
375 		/* production is not committed, caller needs to explicitly commit */
376 		rtn = ring->read;
377 	}
378 	return rtn;
379 }
380 
381 /**
382  * bcm_ring_cons - fetch and "commit" the next index where a ring element may
383  * be consumed.
384  * @ring: pointer to a ring context
385  * @ring_size: size of the ring
386  */
387 static INLINE int
bcm_ring_cons(bcm_ring_t * ring,const int ring_size)388 bcm_ring_cons(bcm_ring_t *ring, const int ring_size)
389 {
390 	int cons_read;
391 	RING_ASSERT(BCM_RING_IS_VALID(ring) && BCM_RING_SIZE_IS_VALID(ring_size));
392 	if (bcm_ring_is_empty(ring)) {
393 		cons_read = BCM_RING_EMPTY;
394 	} else {
395 		cons_read = ring->read;
396 		ring->read = (ring->read + 1) % ring_size; /* read is committed */
397 	}
398 	return cons_read;
399 }
400 
401 /**
402  * bcm_ring_sync_read - on consumption, update peer's read index.
403  * @peer: pointer to peer's producer ring context
404  * @self: pointer to consumer's ring context
405  */
406 static INLINE void
bcm_ring_sync_read(bcm_ring_t * peer,const bcm_ring_t * self)407 bcm_ring_sync_read(bcm_ring_t *peer, const bcm_ring_t *self)
408 {
409 	RING_ASSERT(BCM_RING_IS_VALID(peer));
410 	RING_ASSERT(BCM_RING_IS_VALID(self));
411 	peer->read = self->read; /* flush read update to peer producer */
412 }
413 
414 /**
415  * bcm_ring_sync_write - on consumption, update peer's write index.
416  * @peer: pointer to peer's consumer ring context
417  * @self: pointer to producer's ring context
418  */
419 static INLINE void
bcm_ring_sync_write(bcm_ring_t * peer,const bcm_ring_t * self)420 bcm_ring_sync_write(bcm_ring_t *peer, const bcm_ring_t *self)
421 {
422 	RING_ASSERT(BCM_RING_IS_VALID(peer));
423 	RING_ASSERT(BCM_RING_IS_VALID(self));
424 	peer->write = self->write; /* flush write update to peer consumer */
425 }
426 
427 /**
428  * bcm_ring_prod_avail - fetch total number of available empty slots in the
429  * ring for production.
430  * @ring: pointer to a ring context
431  * @ring_size: size of the ring
432  */
433 static INLINE int
bcm_ring_prod_avail(const bcm_ring_t * ring,const int ring_size)434 bcm_ring_prod_avail(const bcm_ring_t *ring, const int ring_size)
435 {
436 	int prod_avail;
437 	RING_ASSERT(BCM_RING_IS_VALID(ring) && BCM_RING_SIZE_IS_VALID(ring_size));
438 	if (ring->write >= ring->read) {
439 		prod_avail = (ring_size - (ring->write - ring->read) - 1);
440 	} else {
441 		prod_avail = (ring->read - (ring->write + 1));
442 	}
443 	ASSERT(prod_avail < ring_size);
444 	return prod_avail;
445 }
446 
447 /**
448  * bcm_ring_cons_avail - fetch total number of available elements for consumption.
449  * @ring: pointer to a ring context
450  * @ring_size: size of the ring
451  */
452 static INLINE int
bcm_ring_cons_avail(const bcm_ring_t * ring,const int ring_size)453 bcm_ring_cons_avail(const bcm_ring_t *ring, const int ring_size)
454 {
455 	int cons_avail;
456 	RING_ASSERT(BCM_RING_IS_VALID(ring) && BCM_RING_SIZE_IS_VALID(ring_size));
457 	if (ring->read == ring->write) {
458 		cons_avail = 0;
459 	} else if (ring->read > ring->write) {
460 		cons_avail = ((ring_size - ring->read) + ring->write);
461 	} else {
462 		cons_avail = ring->write - ring->read;
463 	}
464 	ASSERT(cons_avail < ring_size);
465 	return cons_avail;
466 }
467 
468 /**
469  * bcm_ring_cons_all - set ring in state where all elements are consumed.
470  * @ring: pointer to a ring context
471  */
472 static INLINE void
bcm_ring_cons_all(bcm_ring_t * ring)473 bcm_ring_cons_all(bcm_ring_t *ring)
474 {
475 	ring->read = ring->write;
476 }
477 
478 /**
479  * Work Queue
480  * A work Queue is composed of a ring of work items, of a specified depth.
481  * It HAS-A bcm_ring object, comprising of a RD and WR offset, to implement a
482  * producer/consumer circular ring.
483  */
484 
485 struct bcm_workq {
486 	bcm_ring_t ring;        /* Ring context abstraction */
487 	struct bcm_workq *peer; /* Peer workq context */
488 	void       *buffer;     /* Buffer storage for work items in workQ */
489 	int        ring_size;   /* Depth of workQ */
490 } __ring_aligned;
491 
492 typedef struct bcm_workq bcm_workq_t;
493 
494 /* #define BCM_WORKQ_DEBUG */
495 #if defined(BCM_WORKQ_DEBUG)
496 #define WORKQ_ASSERT(exp)               ASSERT(exp)
497 #else  /* ! BCM_WORKQ_DEBUG */
498 #define WORKQ_ASSERT(exp)               do {} while (0)
499 #endif /* ! BCM_WORKQ_DEBUG */
500 
501 #define WORKQ_AUDIT(workq) \
502 	WORKQ_ASSERT((workq) != BCM_WORKQ_NULL); \
503 	WORKQ_ASSERT(WORKQ_PEER(workq) != BCM_WORKQ_NULL); \
504 	WORKQ_ASSERT((workq)->buffer == WORKQ_PEER(workq)->buffer); \
505 	WORKQ_ASSERT((workq)->ring_size == WORKQ_PEER(workq)->ring_size);
506 
507 #define BCM_WORKQ_NULL                  ((bcm_workq_t *)NULL)
508 
509 #define WORKQ_PEER(workq)               ((workq)->peer)
510 #define WORKQ_RING(workq)               (&((workq)->ring))
511 #define WORKQ_PEER_RING(workq)          (&((workq)->peer->ring))
512 
513 #define WORKQ_ELEMENT(__elem_type, __workq, __index) ({ \
514 	WORKQ_ASSERT((__workq) != BCM_WORKQ_NULL); \
515 	WORKQ_ASSERT((__index) < ((__workq)->ring_size)); \
516 	((__elem_type *)((__workq)->buffer)) + (__index); \
517 })
518 
519 static INLINE void bcm_workq_init(bcm_workq_t *workq, bcm_workq_t *workq_peer,
520                                   void *buffer, int ring_size);
521 
522 static INLINE bool bcm_workq_is_empty(bcm_workq_t *workq_prod);
523 
524 static INLINE void bcm_workq_prod_sync(bcm_workq_t *workq_prod);
525 static INLINE void bcm_workq_cons_sync(bcm_workq_t *workq_cons);
526 
527 static INLINE void bcm_workq_prod_refresh(bcm_workq_t *workq_prod);
528 static INLINE void bcm_workq_cons_refresh(bcm_workq_t *workq_cons);
529 
530 /**
531  * bcm_workq_init - initialize a workq
532  * @workq: pointer to a workq context
533  * @buffer: pointer to a pre-allocated circular buffer to serve as a ring
534  * @ring_size: size of the ring in terms of max number of elements.
535  */
536 static INLINE void
bcm_workq_init(bcm_workq_t * workq,bcm_workq_t * workq_peer,void * buffer,int ring_size)537 bcm_workq_init(bcm_workq_t *workq, bcm_workq_t *workq_peer,
538                void *buffer, int ring_size)
539 {
540 	ASSERT(workq != BCM_WORKQ_NULL);
541 	ASSERT(workq_peer != BCM_WORKQ_NULL);
542 	ASSERT(buffer != NULL);
543 	ASSERT(ring_size > 0);
544 
545 	WORKQ_PEER(workq) = workq_peer;
546 	WORKQ_PEER(workq_peer) = workq;
547 
548 	bcm_ring_init(WORKQ_RING(workq));
549 	bcm_ring_init(WORKQ_RING(workq_peer));
550 
551 	workq->buffer = workq_peer->buffer = buffer;
552 	workq->ring_size = workq_peer->ring_size = ring_size;
553 }
554 
555 /**
556  * bcm_workq_empty - test whether there is work
557  * @workq_prod: producer's workq
558  */
559 static INLINE bool
bcm_workq_is_empty(bcm_workq_t * workq_prod)560 bcm_workq_is_empty(bcm_workq_t *workq_prod)
561 {
562 	return bcm_ring_is_empty(WORKQ_RING(workq_prod));
563 }
564 
565 /**
566  * bcm_workq_prod_sync - Commit the producer write index to peer workq's ring
567  * @workq_prod: producer's workq whose write index must be synced to peer
568  */
569 static INLINE void
bcm_workq_prod_sync(bcm_workq_t * workq_prod)570 bcm_workq_prod_sync(bcm_workq_t *workq_prod)
571 {
572 	WORKQ_AUDIT(workq_prod);
573 
574 	/* cons::write <--- prod::write */
575 	bcm_ring_sync_write(WORKQ_PEER_RING(workq_prod), WORKQ_RING(workq_prod));
576 }
577 
578 /**
579  * bcm_workq_cons_sync - Commit the consumer read index to the peer workq's ring
580  * @workq_cons: consumer's workq whose read index must be synced to peer
581  */
582 static INLINE void
bcm_workq_cons_sync(bcm_workq_t * workq_cons)583 bcm_workq_cons_sync(bcm_workq_t *workq_cons)
584 {
585 	WORKQ_AUDIT(workq_cons);
586 
587 	/* prod::read <--- cons::read */
588 	bcm_ring_sync_read(WORKQ_PEER_RING(workq_cons), WORKQ_RING(workq_cons));
589 }
590 
591 /**
592  * bcm_workq_prod_refresh - Fetch the updated consumer's read index
593  * @workq_prod: producer's workq whose read index must be refreshed from peer
594  */
595 static INLINE void
bcm_workq_prod_refresh(bcm_workq_t * workq_prod)596 bcm_workq_prod_refresh(bcm_workq_t *workq_prod)
597 {
598 	WORKQ_AUDIT(workq_prod);
599 
600 	/* prod::read <--- cons::read */
601 	bcm_ring_sync_read(WORKQ_RING(workq_prod), WORKQ_PEER_RING(workq_prod));
602 }
603 
604 /**
605  * bcm_workq_cons_refresh - Fetch the updated producer's write index
606  * @workq_cons: consumer's workq whose write index must be refreshed from peer
607  */
608 static INLINE void
bcm_workq_cons_refresh(bcm_workq_t * workq_cons)609 bcm_workq_cons_refresh(bcm_workq_t *workq_cons)
610 {
611 	WORKQ_AUDIT(workq_cons);
612 
613 	/* cons::write <--- prod::write */
614 	bcm_ring_sync_write(WORKQ_RING(workq_cons), WORKQ_PEER_RING(workq_cons));
615 }
616 
617 #endif /* ! __bcm_ring_h_included__ */
618