1 /*
2 *
3 * Intel Management Engine Interface (Intel MEI) Linux driver
4 * Copyright (c) 2003-2012, Intel Corporation.
5 *
6 * This program is free software; you can redistribute it and/or modify it
7 * under the terms and conditions of the GNU General Public License,
8 * version 2, as published by the Free Software Foundation.
9 *
10 * This program is distributed in the hope it will be useful, but WITHOUT
11 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
12 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
13 * more details.
14 *
15 */
16
17 #include <linux/export.h>
18 #include <linux/pci.h>
19 #include <linux/sched.h>
20 #include <linux/wait.h>
21 #include <linux/delay.h>
22
23 #include <linux/mei.h>
24
25 #include "mei_dev.h"
26 #include "hbm.h"
27 #include "client.h"
28
mei_dev_state_str(int state)29 const char *mei_dev_state_str(int state)
30 {
31 #define MEI_DEV_STATE(state) case MEI_DEV_##state: return #state
32 switch (state) {
33 MEI_DEV_STATE(INITIALIZING);
34 MEI_DEV_STATE(INIT_CLIENTS);
35 MEI_DEV_STATE(ENABLED);
36 MEI_DEV_STATE(RESETTING);
37 MEI_DEV_STATE(DISABLED);
38 MEI_DEV_STATE(POWER_DOWN);
39 MEI_DEV_STATE(POWER_UP);
40 default:
41 return "unkown";
42 }
43 #undef MEI_DEV_STATE
44 }
45
mei_device_init(struct mei_device * dev)46 void mei_device_init(struct mei_device *dev)
47 {
48 /* setup our list array */
49 INIT_LIST_HEAD(&dev->file_list);
50 INIT_LIST_HEAD(&dev->device_list);
51 mutex_init(&dev->device_lock);
52 init_waitqueue_head(&dev->wait_hw_ready);
53 init_waitqueue_head(&dev->wait_recvd_msg);
54 init_waitqueue_head(&dev->wait_stop_wd);
55 dev->dev_state = MEI_DEV_INITIALIZING;
56
57 mei_io_list_init(&dev->read_list);
58 mei_io_list_init(&dev->write_list);
59 mei_io_list_init(&dev->write_waiting_list);
60 mei_io_list_init(&dev->ctrl_wr_list);
61 mei_io_list_init(&dev->ctrl_rd_list);
62
63 INIT_DELAYED_WORK(&dev->timer_work, mei_timer);
64 INIT_WORK(&dev->init_work, mei_host_client_init);
65
66 INIT_LIST_HEAD(&dev->wd_cl.link);
67 INIT_LIST_HEAD(&dev->iamthif_cl.link);
68 mei_io_list_init(&dev->amthif_cmd_list);
69 mei_io_list_init(&dev->amthif_rd_complete_list);
70
71 }
72 EXPORT_SYMBOL_GPL(mei_device_init);
73
74 /**
75 * mei_start - initializes host and fw to start work.
76 *
77 * @dev: the device structure
78 *
79 * returns 0 on success, <0 on failure.
80 */
mei_start(struct mei_device * dev)81 int mei_start(struct mei_device *dev)
82 {
83 mutex_lock(&dev->device_lock);
84
85 /* acknowledge interrupt and stop interupts */
86 mei_clear_interrupts(dev);
87
88 mei_hw_config(dev);
89
90 dev_dbg(&dev->pdev->dev, "reset in start the mei device.\n");
91
92 mei_reset(dev, 1);
93
94 if (mei_hbm_start_wait(dev)) {
95 dev_err(&dev->pdev->dev, "HBM haven't started");
96 goto err;
97 }
98
99 if (!mei_host_is_ready(dev)) {
100 dev_err(&dev->pdev->dev, "host is not ready.\n");
101 goto err;
102 }
103
104 if (!mei_hw_is_ready(dev)) {
105 dev_err(&dev->pdev->dev, "ME is not ready.\n");
106 goto err;
107 }
108
109 if (dev->version.major_version != HBM_MAJOR_VERSION ||
110 dev->version.minor_version != HBM_MINOR_VERSION) {
111 dev_dbg(&dev->pdev->dev, "MEI start failed.\n");
112 goto err;
113 }
114
115 dev_dbg(&dev->pdev->dev, "link layer has been established.\n");
116
117 mutex_unlock(&dev->device_lock);
118 return 0;
119 err:
120 dev_err(&dev->pdev->dev, "link layer initialization failed.\n");
121 dev->dev_state = MEI_DEV_DISABLED;
122 mutex_unlock(&dev->device_lock);
123 return -ENODEV;
124 }
125 EXPORT_SYMBOL_GPL(mei_start);
126
127 /**
128 * mei_reset - resets host and fw.
129 *
130 * @dev: the device structure
131 * @interrupts_enabled: if interrupt should be enabled after reset.
132 */
mei_reset(struct mei_device * dev,int interrupts_enabled)133 void mei_reset(struct mei_device *dev, int interrupts_enabled)
134 {
135 bool unexpected;
136
137 unexpected = (dev->dev_state != MEI_DEV_INITIALIZING &&
138 dev->dev_state != MEI_DEV_DISABLED &&
139 dev->dev_state != MEI_DEV_POWER_DOWN &&
140 dev->dev_state != MEI_DEV_POWER_UP);
141
142 mei_hw_reset(dev, interrupts_enabled);
143
144 dev->hbm_state = MEI_HBM_IDLE;
145
146 if (dev->dev_state != MEI_DEV_INITIALIZING) {
147 if (dev->dev_state != MEI_DEV_DISABLED &&
148 dev->dev_state != MEI_DEV_POWER_DOWN)
149 dev->dev_state = MEI_DEV_RESETTING;
150
151 mei_cl_all_disconnect(dev);
152
153 /* remove entry if already in list */
154 dev_dbg(&dev->pdev->dev, "remove iamthif and wd from the file list.\n");
155 mei_cl_unlink(&dev->wd_cl);
156 if (dev->open_handle_count > 0)
157 dev->open_handle_count--;
158 mei_cl_unlink(&dev->iamthif_cl);
159 if (dev->open_handle_count > 0)
160 dev->open_handle_count--;
161
162 mei_amthif_reset_params(dev);
163 memset(&dev->wr_ext_msg, 0, sizeof(dev->wr_ext_msg));
164 }
165
166 dev->me_clients_num = 0;
167 dev->rd_msg_hdr = 0;
168 dev->wd_pending = false;
169
170 if (unexpected)
171 dev_warn(&dev->pdev->dev, "unexpected reset: dev_state = %s\n",
172 mei_dev_state_str(dev->dev_state));
173
174 if (!interrupts_enabled) {
175 dev_dbg(&dev->pdev->dev, "intr not enabled end of reset\n");
176 return;
177 }
178
179 mei_hw_start(dev);
180
181 dev_dbg(&dev->pdev->dev, "link is established start sending messages.\n");
182 /* link is established * start sending messages. */
183
184 dev->dev_state = MEI_DEV_INIT_CLIENTS;
185
186 mei_hbm_start_req(dev);
187
188 /* wake up all readings so they can be interrupted */
189 mei_cl_all_read_wakeup(dev);
190
191 /* remove all waiting requests */
192 mei_cl_all_write_clear(dev);
193 }
194 EXPORT_SYMBOL_GPL(mei_reset);
195
mei_stop(struct mei_device * dev)196 void mei_stop(struct mei_device *dev)
197 {
198 dev_dbg(&dev->pdev->dev, "stopping the device.\n");
199
200 flush_scheduled_work();
201
202 mutex_lock(&dev->device_lock);
203
204 cancel_delayed_work(&dev->timer_work);
205
206 mei_wd_stop(dev);
207
208 mei_nfc_host_exit();
209
210 dev->dev_state = MEI_DEV_POWER_DOWN;
211 mei_reset(dev, 0);
212
213 mutex_unlock(&dev->device_lock);
214
215 mei_watchdog_unregister(dev);
216 }
217 EXPORT_SYMBOL_GPL(mei_stop);
218
219
220
221