1/*
  2 * Copyright (c) 2005 Ammasso, Inc. All rights reserved.
  3 * Copyright (c) 2005 Open Grid Computing, Inc. All rights reserved.
  4 *
  5 * This software is available to you under a choice of one of two
  6 * licenses.  You may choose to be licensed under the terms of the GNU
  7 * General Public License (GPL) Version 2, available from the file
  8 * COPYING in the main directory of this source tree, or the
  9 * OpenIB.org BSD license below:
 10 *
 11 *     Redistribution and use in source and binary forms, with or
 12 *     without modification, are permitted provided that the following
 13 *     conditions are met:
 14 *
 15 *      - Redistributions of source code must retain the above
 16 *        copyright notice, this list of conditions and the following
 17 *        disclaimer.
 18 *
 19 *      - Redistributions in binary form must reproduce the above
 20 *        copyright notice, this list of conditions and the following
 21 *        disclaimer in the documentation and/or other materials
 22 *        provided with the distribution.
 23 *
 24 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
 25 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
 26 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
 27 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
 28 * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
 29 * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
 30 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 31 * SOFTWARE.
 32 */
 33#include "c2.h"
 34#include "c2_mq.h"
 35
 36void *c2_mq_alloc(struct c2_mq *q)
 37{
 38	BUG_ON(q->magic != C2_MQ_MAGIC);
 39	BUG_ON(q->type != C2_MQ_ADAPTER_TARGET);
 40
 41	if (c2_mq_full(q)) {
 42		return NULL;
 43	} else {
 44#ifdef DEBUG
 45		struct c2wr_hdr *m =
 46		    (struct c2wr_hdr *) (q->msg_pool.host + q->priv * q->msg_size);
 47#ifdef CCMSGMAGIC
 48		BUG_ON(m->magic != be32_to_cpu(~CCWR_MAGIC));
 49		m->magic = cpu_to_be32(CCWR_MAGIC);
 50#endif
 51		return m;
 52#else
 53		return q->msg_pool.host + q->priv * q->msg_size;
 54#endif
 55	}
 56}
 57
 58void c2_mq_produce(struct c2_mq *q)
 59{
 60	BUG_ON(q->magic != C2_MQ_MAGIC);
 61	BUG_ON(q->type != C2_MQ_ADAPTER_TARGET);
 62
 63	if (!c2_mq_full(q)) {
 64		q->priv = (q->priv + 1) % q->q_size;
 65		q->hint_count++;
 66		/* Update peer's offset. */
 67		__raw_writew((__force u16) cpu_to_be16(q->priv), &q->peer->shared);
 68	}
 69}
 70
 71void *c2_mq_consume(struct c2_mq *q)
 72{
 73	BUG_ON(q->magic != C2_MQ_MAGIC);
 74	BUG_ON(q->type != C2_MQ_HOST_TARGET);
 75
 76	if (c2_mq_empty(q)) {
 77		return NULL;
 78	} else {
 79#ifdef DEBUG
 80		struct c2wr_hdr *m = (struct c2wr_hdr *)
 81		    (q->msg_pool.host + q->priv * q->msg_size);
 82#ifdef CCMSGMAGIC
 83		BUG_ON(m->magic != be32_to_cpu(CCWR_MAGIC));
 84#endif
 85		return m;
 86#else
 87		return q->msg_pool.host + q->priv * q->msg_size;
 88#endif
 89	}
 90}
 91
 92void c2_mq_free(struct c2_mq *q)
 93{
 94	BUG_ON(q->magic != C2_MQ_MAGIC);
 95	BUG_ON(q->type != C2_MQ_HOST_TARGET);
 96
 97	if (!c2_mq_empty(q)) {
 98
 99#ifdef CCMSGMAGIC
100		{
101			struct c2wr_hdr __iomem *m = (struct c2wr_hdr __iomem *)
102			    (q->msg_pool.adapter + q->priv * q->msg_size);
103			__raw_writel(cpu_to_be32(~CCWR_MAGIC), &m->magic);
104		}
105#endif
106		q->priv = (q->priv + 1) % q->q_size;
107		/* Update peer's offset. */
108		__raw_writew((__force u16) cpu_to_be16(q->priv), &q->peer->shared);
109	}
110}
111
112
113void c2_mq_lconsume(struct c2_mq *q, u32 wqe_count)
114{
115	BUG_ON(q->magic != C2_MQ_MAGIC);
116	BUG_ON(q->type != C2_MQ_ADAPTER_TARGET);
117
118	while (wqe_count--) {
119		BUG_ON(c2_mq_empty(q));
120		*q->shared = cpu_to_be16((be16_to_cpu(*q->shared)+1) % q->q_size);
121	}
122}
123
124#if 0
125u32 c2_mq_count(struct c2_mq *q)
126{
127	s32 count;
128
129	if (q->type == C2_MQ_HOST_TARGET)
130		count = be16_to_cpu(*q->shared) - q->priv;
131	else
132		count = q->priv - be16_to_cpu(*q->shared);
133
134	if (count < 0)
135		count += q->q_size;
136
137	return (u32) count;
138}
139#endif  /*  0  */
140
141void c2_mq_req_init(struct c2_mq *q, u32 index, u32 q_size, u32 msg_size,
142		    u8 __iomem *pool_start, u16 __iomem *peer, u32 type)
143{
144	BUG_ON(!q->shared);
145
146	/* This code assumes the byte swapping has already been done! */
147	q->index = index;
148	q->q_size = q_size;
149	q->msg_size = msg_size;
150	q->msg_pool.adapter = pool_start;
151	q->peer = (struct c2_mq_shared __iomem *) peer;
152	q->magic = C2_MQ_MAGIC;
153	q->type = type;
154	q->priv = 0;
155	q->hint_count = 0;
156	return;
157}
158void c2_mq_rep_init(struct c2_mq *q, u32 index, u32 q_size, u32 msg_size,
159		    u8 *pool_start, u16 __iomem *peer, u32 type)
160{
161	BUG_ON(!q->shared);
162
163	/* This code assumes the byte swapping has already been done! */
164	q->index = index;
165	q->q_size = q_size;
166	q->msg_size = msg_size;
167	q->msg_pool.host = pool_start;
168	q->peer = (struct c2_mq_shared __iomem *) peer;
169	q->magic = C2_MQ_MAGIC;
170	q->type = type;
171	q->priv = 0;
172	q->hint_count = 0;
173	return;
174}