1 /*
2  * Copyright (c) 2013-2015, Mellanox Technologies. All rights reserved.
3  *
4  * This software is available to you under a choice of one of two
5  * licenses.  You may choose to be licensed under the terms of the GNU
6  * General Public License (GPL) Version 2, available from the file
7  * COPYING in the main directory of this source tree, or the
8  * OpenIB.org BSD license below:
9  *
10  *     Redistribution and use in source and binary forms, with or
11  *     without modification, are permitted provided that the following
12  *     conditions are met:
13  *
14  *      - Redistributions of source code must retain the above
15  *        copyright notice, this list of conditions and the following
16  *        disclaimer.
17  *
18  *      - Redistributions in binary form must reproduce the above
19  *        copyright notice, this list of conditions and the following
20  *        disclaimer in the documentation and/or other materials
21  *        provided with the distribution.
22  *
23  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
24  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
25  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
26  * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
27  * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
28  * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
29  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
30  * SOFTWARE.
31  */
32 
33 #include <linux/kernel.h>
34 #include <linux/module.h>
35 #include <linux/hardirq.h>
36 #include <linux/mlx5/driver.h>
37 #include <linux/mlx5/cmd.h>
38 #include <rdma/ib_verbs.h>
39 #include <linux/mlx5/cq.h>
40 #include "mlx5_core.h"
41 
42 #define TASKLET_MAX_TIME 2
43 #define TASKLET_MAX_TIME_JIFFIES msecs_to_jiffies(TASKLET_MAX_TIME)
44 
45 void mlx5_cq_tasklet_cb(unsigned long data)
46 {
47 	unsigned long flags;
48 	unsigned long end = jiffies + TASKLET_MAX_TIME_JIFFIES;
49 	struct mlx5_eq_tasklet *ctx = (struct mlx5_eq_tasklet *)data;
50 	struct mlx5_core_cq *mcq;
51 	struct mlx5_core_cq *temp;
52 
53 	spin_lock_irqsave(&ctx->lock, flags);
54 	list_splice_tail_init(&ctx->list, &ctx->process_list);
55 	spin_unlock_irqrestore(&ctx->lock, flags);
56 
57 	list_for_each_entry_safe(mcq, temp, &ctx->process_list,
58 				 tasklet_ctx.list) {
59 		list_del_init(&mcq->tasklet_ctx.list);
60 		mcq->tasklet_ctx.comp(mcq);
61 		mlx5_cq_put(mcq);
62 		if (time_after(jiffies, end))
63 			break;
64 	}
65 
66 	if (!list_empty(&ctx->process_list))
67 		tasklet_schedule(&ctx->task);
68 }
69 
70 static void mlx5_add_cq_to_tasklet(struct mlx5_core_cq *cq)
71 {
72 	unsigned long flags;
73 	struct mlx5_eq_tasklet *tasklet_ctx = cq->tasklet_ctx.priv;
74 
75 	spin_lock_irqsave(&tasklet_ctx->lock, flags);
76 	/* When migrating CQs between EQs will be implemented, please note
77 	 * that you need to sync this point. It is possible that
78 	 * while migrating a CQ, completions on the old EQs could
79 	 * still arrive.
80 	 */
81 	if (list_empty_careful(&cq->tasklet_ctx.list)) {
82 		mlx5_cq_hold(cq);
83 		list_add_tail(&cq->tasklet_ctx.list, &tasklet_ctx->list);
84 	}
85 	spin_unlock_irqrestore(&tasklet_ctx->lock, flags);
86 }
87 
88 int mlx5_core_create_cq(struct mlx5_core_dev *dev, struct mlx5_core_cq *cq,
89 			u32 *in, int inlen)
90 {
91 	int eqn = MLX5_GET(cqc, MLX5_ADDR_OF(create_cq_in, in, cq_context), c_eqn);
92 	u32 dout[MLX5_ST_SZ_DW(destroy_cq_out)];
93 	u32 out[MLX5_ST_SZ_DW(create_cq_out)];
94 	u32 din[MLX5_ST_SZ_DW(destroy_cq_in)];
95 	struct mlx5_eq *eq;
96 	int err;
97 
98 	eq = mlx5_eqn2eq(dev, eqn);
99 	if (IS_ERR(eq))
100 		return PTR_ERR(eq);
101 
102 	memset(out, 0, sizeof(out));
103 	MLX5_SET(create_cq_in, in, opcode, MLX5_CMD_OP_CREATE_CQ);
104 	err = mlx5_cmd_exec(dev, in, inlen, out, sizeof(out));
105 	if (err)
106 		return err;
107 
108 	cq->cqn = MLX5_GET(create_cq_out, out, cqn);
109 	cq->cons_index = 0;
110 	cq->arm_sn     = 0;
111 	cq->eq         = eq;
112 	refcount_set(&cq->refcount, 1);
113 	init_completion(&cq->free);
114 	if (!cq->comp)
115 		cq->comp = mlx5_add_cq_to_tasklet;
116 	/* assuming CQ will be deleted before the EQ */
117 	cq->tasklet_ctx.priv = &eq->tasklet_ctx;
118 	INIT_LIST_HEAD(&cq->tasklet_ctx.list);
119 
120 	/* Add to comp EQ CQ tree to recv comp events */
121 	err = mlx5_eq_add_cq(eq, cq);
122 	if (err)
123 		goto err_cmd;
124 
125 	/* Add to async EQ CQ tree to recv async events */
126 	err = mlx5_eq_add_cq(&dev->priv.eq_table.async_eq, cq);
127 	if (err)
128 		goto err_cq_add;
129 
130 	cq->pid = current->pid;
131 	err = mlx5_debug_cq_add(dev, cq);
132 	if (err)
133 		mlx5_core_dbg(dev, "failed adding CP 0x%x to debug file system\n",
134 			      cq->cqn);
135 
136 	cq->uar = dev->priv.uar;
137 
138 	return 0;
139 
140 err_cq_add:
141 	mlx5_eq_del_cq(eq, cq);
142 err_cmd:
143 	memset(din, 0, sizeof(din));
144 	memset(dout, 0, sizeof(dout));
145 	MLX5_SET(destroy_cq_in, din, opcode, MLX5_CMD_OP_DESTROY_CQ);
146 	MLX5_SET(destroy_cq_in, din, cqn, cq->cqn);
147 	mlx5_cmd_exec(dev, din, sizeof(din), dout, sizeof(dout));
148 	return err;
149 }
150 EXPORT_SYMBOL(mlx5_core_create_cq);
151 
152 int mlx5_core_destroy_cq(struct mlx5_core_dev *dev, struct mlx5_core_cq *cq)
153 {
154 	u32 out[MLX5_ST_SZ_DW(destroy_cq_out)] = {0};
155 	u32 in[MLX5_ST_SZ_DW(destroy_cq_in)] = {0};
156 	int err;
157 
158 	err = mlx5_eq_del_cq(&dev->priv.eq_table.async_eq, cq);
159 	if (err)
160 		return err;
161 
162 	err = mlx5_eq_del_cq(cq->eq, cq);
163 	if (err)
164 		return err;
165 
166 	MLX5_SET(destroy_cq_in, in, opcode, MLX5_CMD_OP_DESTROY_CQ);
167 	MLX5_SET(destroy_cq_in, in, cqn, cq->cqn);
168 	err = mlx5_cmd_exec(dev, in, sizeof(in), out, sizeof(out));
169 	if (err)
170 		return err;
171 
172 	synchronize_irq(cq->irqn);
173 
174 	mlx5_debug_cq_remove(dev, cq);
175 	mlx5_cq_put(cq);
176 	wait_for_completion(&cq->free);
177 
178 	return 0;
179 }
180 EXPORT_SYMBOL(mlx5_core_destroy_cq);
181 
182 int mlx5_core_query_cq(struct mlx5_core_dev *dev, struct mlx5_core_cq *cq,
183 		       u32 *out, int outlen)
184 {
185 	u32 in[MLX5_ST_SZ_DW(query_cq_in)] = {0};
186 
187 	MLX5_SET(query_cq_in, in, opcode, MLX5_CMD_OP_QUERY_CQ);
188 	MLX5_SET(query_cq_in, in, cqn, cq->cqn);
189 	return mlx5_cmd_exec(dev, in, sizeof(in), out, outlen);
190 }
191 EXPORT_SYMBOL(mlx5_core_query_cq);
192 
193 int mlx5_core_modify_cq(struct mlx5_core_dev *dev, struct mlx5_core_cq *cq,
194 			u32 *in, int inlen)
195 {
196 	u32 out[MLX5_ST_SZ_DW(modify_cq_out)] = {0};
197 
198 	MLX5_SET(modify_cq_in, in, opcode, MLX5_CMD_OP_MODIFY_CQ);
199 	return mlx5_cmd_exec(dev, in, inlen, out, sizeof(out));
200 }
201 EXPORT_SYMBOL(mlx5_core_modify_cq);
202 
203 int mlx5_core_modify_cq_moderation(struct mlx5_core_dev *dev,
204 				   struct mlx5_core_cq *cq,
205 				   u16 cq_period,
206 				   u16 cq_max_count)
207 {
208 	u32 in[MLX5_ST_SZ_DW(modify_cq_in)] = {0};
209 	void *cqc;
210 
211 	MLX5_SET(modify_cq_in, in, cqn, cq->cqn);
212 	cqc = MLX5_ADDR_OF(modify_cq_in, in, cq_context);
213 	MLX5_SET(cqc, cqc, cq_period, cq_period);
214 	MLX5_SET(cqc, cqc, cq_max_count, cq_max_count);
215 	MLX5_SET(modify_cq_in, in,
216 		 modify_field_select_resize_field_select.modify_field_select.modify_field_select,
217 		 MLX5_CQ_MODIFY_PERIOD | MLX5_CQ_MODIFY_COUNT);
218 
219 	return mlx5_core_modify_cq(dev, cq, in, sizeof(in));
220 }
221 EXPORT_SYMBOL(mlx5_core_modify_cq_moderation);
222