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16#include <linux/kernel.h>
17#include <linux/module.h>
18#include <linux/moduleparam.h>
19#include <linux/device.h>
20#include <linux/pci.h>
21#include <linux/sched.h>
22#include <linux/watchdog.h>
23
24#include <linux/mei.h>
25
26#include "mei_dev.h"
27#include "hbm.h"
28#include "hw-me.h"
29#include "client.h"
30
31static const u8 mei_start_wd_params[] = { 0x02, 0x12, 0x13, 0x10 };
32static const u8 mei_stop_wd_params[] = { 0x02, 0x02, 0x14, 0x10 };
33
34const u8 mei_wd_state_independence_msg[3][4] = {
35 {0x05, 0x02, 0x51, 0x10},
36 {0x05, 0x02, 0x52, 0x10},
37 {0x07, 0x02, 0x01, 0x10}
38};
39
40
41
42
43#define INTEL_AMT_WATCHDOG_ID "INTCAMT"
44
45
46const uuid_le mei_wd_guid = UUID_LE(0x05B79A6F, 0x4628, 0x4D7F, 0x89,
47 0x9D, 0xA9, 0x15, 0x14, 0xCB,
48 0x32, 0xAB);
49
50static void mei_wd_set_start_timeout(struct mei_device *dev, u16 timeout)
51{
52 dev_dbg(&dev->pdev->dev, "wd: set timeout=%d.\n", timeout);
53 memcpy(dev->wd_data, mei_start_wd_params, MEI_WD_HDR_SIZE);
54 memcpy(dev->wd_data + MEI_WD_HDR_SIZE, &timeout, sizeof(u16));
55}
56
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63
64
65
66int mei_wd_host_init(struct mei_device *dev)
67{
68 struct mei_cl *cl = &dev->wd_cl;
69 int i;
70 int ret;
71
72 mei_cl_init(cl, dev);
73
74 dev->wd_timeout = MEI_WD_DEFAULT_TIMEOUT;
75 dev->wd_state = MEI_WD_IDLE;
76
77
78
79 i = mei_me_cl_by_uuid(dev, &mei_wd_guid);
80 if (i < 0) {
81 dev_info(&dev->pdev->dev, "wd: failed to find the client\n");
82 return -ENOENT;
83 }
84
85 cl->me_client_id = dev->me_clients[i].client_id;
86
87 ret = mei_cl_link(cl, MEI_WD_HOST_CLIENT_ID);
88
89 if (ret < 0) {
90 dev_info(&dev->pdev->dev, "wd: failed link client\n");
91 return -ENOENT;
92 }
93
94 cl->state = MEI_FILE_CONNECTING;
95
96 if (mei_hbm_cl_connect_req(dev, cl)) {
97 dev_err(&dev->pdev->dev, "wd: failed to connect to the client\n");
98 cl->state = MEI_FILE_DISCONNECTED;
99 cl->host_client_id = 0;
100 return -EIO;
101 }
102 cl->timer_count = MEI_CONNECT_TIMEOUT;
103
104 return 0;
105}
106
107
108
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110
111
112
113
114
115
116int mei_wd_send(struct mei_device *dev)
117{
118 struct mei_msg_hdr hdr;
119
120 hdr.host_addr = dev->wd_cl.host_client_id;
121 hdr.me_addr = dev->wd_cl.me_client_id;
122 hdr.msg_complete = 1;
123 hdr.reserved = 0;
124
125 if (!memcmp(dev->wd_data, mei_start_wd_params, MEI_WD_HDR_SIZE))
126 hdr.length = MEI_WD_START_MSG_SIZE;
127 else if (!memcmp(dev->wd_data, mei_stop_wd_params, MEI_WD_HDR_SIZE))
128 hdr.length = MEI_WD_STOP_MSG_SIZE;
129 else
130 return -EINVAL;
131
132 return mei_write_message(dev, &hdr, dev->wd_data);
133}
134
135
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138
139
140
141
142
143
144
145int mei_wd_stop(struct mei_device *dev)
146{
147 int ret;
148
149 if (dev->wd_cl.state != MEI_FILE_CONNECTED ||
150 dev->wd_state != MEI_WD_RUNNING)
151 return 0;
152
153 memcpy(dev->wd_data, mei_stop_wd_params, MEI_WD_STOP_MSG_SIZE);
154
155 dev->wd_state = MEI_WD_STOPPING;
156
157 ret = mei_cl_flow_ctrl_creds(&dev->wd_cl);
158 if (ret < 0)
159 goto out;
160
161 if (ret && dev->hbuf_is_ready) {
162 ret = 0;
163 dev->hbuf_is_ready = false;
164
165 if (!mei_wd_send(dev)) {
166 ret = mei_cl_flow_ctrl_reduce(&dev->wd_cl);
167 if (ret)
168 goto out;
169 } else {
170 dev_err(&dev->pdev->dev, "wd: send stop failed\n");
171 }
172
173 dev->wd_pending = false;
174 } else {
175 dev->wd_pending = true;
176 }
177
178 mutex_unlock(&dev->device_lock);
179
180 ret = wait_event_interruptible_timeout(dev->wait_stop_wd,
181 dev->wd_state == MEI_WD_IDLE,
182 msecs_to_jiffies(MEI_WD_STOP_TIMEOUT));
183 mutex_lock(&dev->device_lock);
184 if (dev->wd_state == MEI_WD_IDLE) {
185 dev_dbg(&dev->pdev->dev, "wd: stop completed ret=%d.\n", ret);
186 ret = 0;
187 } else {
188 if (!ret)
189 ret = -ETIMEDOUT;
190 dev_warn(&dev->pdev->dev,
191 "wd: stop failed to complete ret=%d.\n", ret);
192 }
193
194out:
195 return ret;
196}
197
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201
202
203
204
205static int mei_wd_ops_start(struct watchdog_device *wd_dev)
206{
207 int err = -ENODEV;
208 struct mei_device *dev;
209
210 dev = watchdog_get_drvdata(wd_dev);
211 if (!dev)
212 return -ENODEV;
213
214 mutex_lock(&dev->device_lock);
215
216 if (dev->dev_state != MEI_DEV_ENABLED) {
217 dev_dbg(&dev->pdev->dev,
218 "wd: dev_state != MEI_DEV_ENABLED dev_state = %s\n",
219 mei_dev_state_str(dev->dev_state));
220 goto end_unlock;
221 }
222
223 if (dev->wd_cl.state != MEI_FILE_CONNECTED) {
224 dev_dbg(&dev->pdev->dev,
225 "MEI Driver is not connected to Watchdog Client\n");
226 goto end_unlock;
227 }
228
229 mei_wd_set_start_timeout(dev, dev->wd_timeout);
230
231 err = 0;
232end_unlock:
233 mutex_unlock(&dev->device_lock);
234 return err;
235}
236
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241
242
243
244static int mei_wd_ops_stop(struct watchdog_device *wd_dev)
245{
246 struct mei_device *dev;
247
248 dev = watchdog_get_drvdata(wd_dev);
249 if (!dev)
250 return -ENODEV;
251
252 mutex_lock(&dev->device_lock);
253 mei_wd_stop(dev);
254 mutex_unlock(&dev->device_lock);
255
256 return 0;
257}
258
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262
263
264
265
266static int mei_wd_ops_ping(struct watchdog_device *wd_dev)
267{
268 int ret = 0;
269 struct mei_device *dev;
270
271 dev = watchdog_get_drvdata(wd_dev);
272 if (!dev)
273 return -ENODEV;
274
275 mutex_lock(&dev->device_lock);
276
277 if (dev->wd_cl.state != MEI_FILE_CONNECTED) {
278 dev_err(&dev->pdev->dev, "wd: not connected.\n");
279 ret = -ENODEV;
280 goto end;
281 }
282
283 dev->wd_state = MEI_WD_RUNNING;
284
285
286 if (dev->hbuf_is_ready && mei_cl_flow_ctrl_creds(&dev->wd_cl) > 0) {
287
288 dev->hbuf_is_ready = false;
289 dev_dbg(&dev->pdev->dev, "wd: sending ping\n");
290
291 if (mei_wd_send(dev)) {
292 dev_err(&dev->pdev->dev, "wd: send failed.\n");
293 ret = -EIO;
294 goto end;
295 }
296
297 if (mei_cl_flow_ctrl_reduce(&dev->wd_cl)) {
298 dev_err(&dev->pdev->dev,
299 "wd: mei_cl_flow_ctrl_reduce() failed.\n");
300 ret = -EIO;
301 goto end;
302 }
303
304 } else {
305 dev->wd_pending = true;
306 }
307
308end:
309 mutex_unlock(&dev->device_lock);
310 return ret;
311}
312
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317
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319
320
321static int mei_wd_ops_set_timeout(struct watchdog_device *wd_dev,
322 unsigned int timeout)
323{
324 struct mei_device *dev;
325
326 dev = watchdog_get_drvdata(wd_dev);
327 if (!dev)
328 return -ENODEV;
329
330
331 if (timeout < MEI_WD_MIN_TIMEOUT || timeout > MEI_WD_MAX_TIMEOUT)
332 return -EINVAL;
333
334 mutex_lock(&dev->device_lock);
335
336 dev->wd_timeout = timeout;
337 wd_dev->timeout = timeout;
338 mei_wd_set_start_timeout(dev, dev->wd_timeout);
339
340 mutex_unlock(&dev->device_lock);
341
342 return 0;
343}
344
345
346
347
348static const struct watchdog_ops wd_ops = {
349 .owner = THIS_MODULE,
350 .start = mei_wd_ops_start,
351 .stop = mei_wd_ops_stop,
352 .ping = mei_wd_ops_ping,
353 .set_timeout = mei_wd_ops_set_timeout,
354};
355static const struct watchdog_info wd_info = {
356 .identity = INTEL_AMT_WATCHDOG_ID,
357 .options = WDIOF_KEEPALIVEPING |
358 WDIOF_SETTIMEOUT |
359 WDIOF_ALARMONLY,
360};
361
362static struct watchdog_device amt_wd_dev = {
363 .info = &wd_info,
364 .ops = &wd_ops,
365 .timeout = MEI_WD_DEFAULT_TIMEOUT,
366 .min_timeout = MEI_WD_MIN_TIMEOUT,
367 .max_timeout = MEI_WD_MAX_TIMEOUT,
368};
369
370
371void mei_watchdog_register(struct mei_device *dev)
372{
373 if (watchdog_register_device(&amt_wd_dev)) {
374 dev_err(&dev->pdev->dev,
375 "wd: unable to register watchdog device.\n");
376 return;
377 }
378
379 dev_dbg(&dev->pdev->dev,
380 "wd: successfully register watchdog interface.\n");
381 watchdog_set_drvdata(&amt_wd_dev, dev);
382}
383
384void mei_watchdog_unregister(struct mei_device *dev)
385{
386 if (watchdog_get_drvdata(&amt_wd_dev) == NULL)
387 return;
388
389 watchdog_set_drvdata(&amt_wd_dev, NULL);
390 watchdog_unregister_device(&amt_wd_dev);
391}
392
393
