1 /*
2 * Copyright (c) 2012-2016 VMware, Inc. All rights reserved.
3 *
4 * This program is free software; you can redistribute it and/or
5 * modify it under the terms of EITHER the GNU General Public License
6 * version 2 as published by the Free Software Foundation or the BSD
7 * 2-Clause License. This program is distributed in the hope that it
8 * will be useful, but WITHOUT ANY WARRANTY; WITHOUT EVEN THE IMPLIED
9 * WARRANTY OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.
10 * See the GNU General Public License version 2 for more details at
11 * http://www.gnu.org/licenses/old-licenses/gpl-2.0.en.html.
12 *
13 * You should have received a copy of the GNU General Public License
14 * along with this program available in the file COPYING in the main
15 * directory of this source tree.
16 *
17 * The BSD 2-Clause License
18 *
19 * Redistribution and use in source and binary forms, with or
20 * without modification, are permitted provided that the following
21 * conditions are met:
22 *
23 * - Redistributions of source code must retain the above
24 * copyright notice, this list of conditions and the following
25 * disclaimer.
26 *
27 * - Redistributions in binary form must reproduce the above
28 * copyright notice, this list of conditions and the following
29 * disclaimer in the documentation and/or other materials
30 * provided with the distribution.
31 *
32 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
33 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
34 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
35 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
36 * COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
37 * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
38 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
39 * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
40 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
41 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
42 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
43 * OF THE POSSIBILITY OF SUCH DAMAGE.
44 */
45
46 #include <linux/list.h>
47
48 #include "pvrdma.h"
49
50 #define PVRDMA_CMD_TIMEOUT 10000 /* ms */
51
52 static inline int pvrdma_cmd_recv(struct pvrdma_dev *dev,
53 union pvrdma_cmd_resp *resp,
54 unsigned resp_code)
55 {
56 int err;
57
58 dev_dbg(&dev->pdev->dev, "receive response from device\n");
59
60 err = wait_for_completion_interruptible_timeout(&dev->cmd_done,
61 msecs_to_jiffies(PVRDMA_CMD_TIMEOUT));
62 if (err == 0 || err == -ERESTARTSYS) {
63 dev_warn(&dev->pdev->dev,
64 "completion timeout or interrupted\n");
65 return -ETIMEDOUT;
66 }
67
68 spin_lock(&dev->cmd_lock);
69 memcpy(resp, dev->resp_slot, sizeof(*resp));
70 spin_unlock(&dev->cmd_lock);
71
72 if (resp->hdr.ack != resp_code) {
73 dev_warn(&dev->pdev->dev,
74 "unknown response %#x expected %#x\n",
75 resp->hdr.ack, resp_code);
76 return -EFAULT;
77 }
78
79 return 0;
80 }
81
82 int
83 pvrdma_cmd_post(struct pvrdma_dev *dev, union pvrdma_cmd_req *req,
84 union pvrdma_cmd_resp *resp, unsigned resp_code)
85 {
86 int err;
87
88 dev_dbg(&dev->pdev->dev, "post request to device\n");
89
90 /* Serializiation */
91 down(&dev->cmd_sema);
92
93 BUILD_BUG_ON(sizeof(union pvrdma_cmd_req) !=
94 sizeof(struct pvrdma_cmd_modify_qp));
95
96 spin_lock(&dev->cmd_lock);
97 memcpy(dev->cmd_slot, req, sizeof(*req));
98 spin_unlock(&dev->cmd_lock);
99
100 init_completion(&dev->cmd_done);
101 pvrdma_write_reg(dev, PVRDMA_REG_REQUEST, 0);
102
103 /* Make sure the request is written before reading status. */
104 mb();
105
106 err = pvrdma_read_reg(dev, PVRDMA_REG_ERR);
107 if (err == 0) {
108 if (resp != NULL)
109 err = pvrdma_cmd_recv(dev, resp, resp_code);
110 } else {
111 dev_warn(&dev->pdev->dev,
112 "failed to write request error reg: %d\n", err);
113 err = -EFAULT;
114 }
115
116 up(&dev->cmd_sema);
117
118 return err;
119 }