3 * Intel Management Engine Interface (Intel MEI) Linux driver
4 * Copyright (c) 2003-2012, Intel Corporation.
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.
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
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>
24 #include <linux/mei.h>
31 static const u8 mei_start_wd_params
[] = { 0x02, 0x12, 0x13, 0x10 };
32 static const u8 mei_stop_wd_params
[] = { 0x02, 0x02, 0x14, 0x10 };
34 const u8 mei_wd_state_independence_msg
[3][4] = {
35 {0x05, 0x02, 0x51, 0x10},
36 {0x05, 0x02, 0x52, 0x10},
37 {0x07, 0x02, 0x01, 0x10}
43 #define INTEL_AMT_WATCHDOG_ID "INTCAMT"
45 /* UUIDs for AMT F/W clients */
46 const uuid_le mei_wd_guid
= UUID_LE(0x05B79A6F, 0x4628, 0x4D7F, 0x89,
47 0x9D, 0xA9, 0x15, 0x14, 0xCB,
50 static void mei_wd_set_start_timeout(struct mei_device
*dev
, u16 timeout
)
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
));
58 * mei_wd_host_init - connect to the watchdog client
60 * @dev: the device structure
62 * returns -ENENT if wd client cannot be found
63 * -EIO if write has failed
66 int mei_wd_host_init(struct mei_device
*dev
)
68 struct mei_cl
*cl
= &dev
->wd_cl
;
74 dev
->wd_timeout
= MEI_WD_DEFAULT_TIMEOUT
;
75 dev
->wd_state
= MEI_WD_IDLE
;
78 /* check for valid client id */
79 i
= mei_me_cl_by_uuid(dev
, &mei_wd_guid
);
81 dev_info(&dev
->pdev
->dev
, "wd: failed to find the client\n");
85 cl
->me_client_id
= dev
->me_clients
[i
].client_id
;
87 ret
= mei_cl_link(cl
, MEI_WD_HOST_CLIENT_ID
);
90 dev_info(&dev
->pdev
->dev
, "wd: failed link client\n");
94 cl
->state
= MEI_FILE_CONNECTING
;
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;
102 cl
->timer_count
= MEI_CONNECT_TIMEOUT
;
108 * mei_wd_send - sends watch dog message to fw.
110 * @dev: the device structure
112 * returns 0 if success,
113 * -EIO when message send fails
114 * -EINVAL when invalid message is to be sent
116 int mei_wd_send(struct mei_device
*dev
)
118 struct mei_msg_hdr hdr
;
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;
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
;
132 return mei_write_message(dev
, &hdr
, dev
->wd_data
);
136 * mei_wd_stop - sends watchdog stop message to fw.
138 * @dev: the device structure
139 * @preserve: indicate if to keep the timeout value
141 * returns 0 if success,
142 * -EIO when message send fails
143 * -EINVAL when invalid message is to be sent
145 int mei_wd_stop(struct mei_device
*dev
)
149 if (dev
->wd_cl
.state
!= MEI_FILE_CONNECTED
||
150 dev
->wd_state
!= MEI_WD_RUNNING
)
153 memcpy(dev
->wd_data
, mei_stop_wd_params
, MEI_WD_STOP_MSG_SIZE
);
155 dev
->wd_state
= MEI_WD_STOPPING
;
157 ret
= mei_cl_flow_ctrl_creds(&dev
->wd_cl
);
161 if (ret
&& dev
->hbuf_is_ready
) {
163 dev
->hbuf_is_ready
= false;
165 if (!mei_wd_send(dev
)) {
166 ret
= mei_cl_flow_ctrl_reduce(&dev
->wd_cl
);
170 dev_err(&dev
->pdev
->dev
, "wd: send stop failed\n");
173 dev
->wd_pending
= false;
175 dev
->wd_pending
= true;
178 mutex_unlock(&dev
->device_lock
);
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
);
190 dev_warn(&dev
->pdev
->dev
,
191 "wd: stop failed to complete ret=%d.\n", ret
);
199 * mei_wd_ops_start - wd start command from the watchdog core.
201 * @wd_dev - watchdog device struct
203 * returns 0 if success, negative errno code for failure
205 static int mei_wd_ops_start(struct watchdog_device
*wd_dev
)
208 struct mei_device
*dev
;
210 dev
= watchdog_get_drvdata(wd_dev
);
214 mutex_lock(&dev
->device_lock
);
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
));
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");
229 mei_wd_set_start_timeout(dev
, dev
->wd_timeout
);
233 mutex_unlock(&dev
->device_lock
);
238 * mei_wd_ops_stop - wd stop command from the watchdog core.
240 * @wd_dev - watchdog device struct
242 * returns 0 if success, negative errno code for failure
244 static int mei_wd_ops_stop(struct watchdog_device
*wd_dev
)
246 struct mei_device
*dev
;
248 dev
= watchdog_get_drvdata(wd_dev
);
252 mutex_lock(&dev
->device_lock
);
254 mutex_unlock(&dev
->device_lock
);
260 * mei_wd_ops_ping - wd ping command from the watchdog core.
262 * @wd_dev - watchdog device struct
264 * returns 0 if success, negative errno code for failure
266 static int mei_wd_ops_ping(struct watchdog_device
*wd_dev
)
269 struct mei_device
*dev
;
271 dev
= watchdog_get_drvdata(wd_dev
);
275 mutex_lock(&dev
->device_lock
);
277 if (dev
->wd_cl
.state
!= MEI_FILE_CONNECTED
) {
278 dev_err(&dev
->pdev
->dev
, "wd: not connected.\n");
283 dev
->wd_state
= MEI_WD_RUNNING
;
285 /* Check if we can send the ping to HW*/
286 if (dev
->hbuf_is_ready
&& mei_cl_flow_ctrl_creds(&dev
->wd_cl
) > 0) {
288 dev
->hbuf_is_ready
= false;
289 dev_dbg(&dev
->pdev
->dev
, "wd: sending ping\n");
291 if (mei_wd_send(dev
)) {
292 dev_err(&dev
->pdev
->dev
, "wd: send failed.\n");
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");
305 dev
->wd_pending
= true;
309 mutex_unlock(&dev
->device_lock
);
314 * mei_wd_ops_set_timeout - wd set timeout command from the watchdog core.
316 * @wd_dev - watchdog device struct
317 * @timeout - timeout value to set
319 * returns 0 if success, negative errno code for failure
321 static int mei_wd_ops_set_timeout(struct watchdog_device
*wd_dev
,
322 unsigned int timeout
)
324 struct mei_device
*dev
;
326 dev
= watchdog_get_drvdata(wd_dev
);
330 /* Check Timeout value */
331 if (timeout
< MEI_WD_MIN_TIMEOUT
|| timeout
> MEI_WD_MAX_TIMEOUT
)
334 mutex_lock(&dev
->device_lock
);
336 dev
->wd_timeout
= timeout
;
337 wd_dev
->timeout
= timeout
;
338 mei_wd_set_start_timeout(dev
, dev
->wd_timeout
);
340 mutex_unlock(&dev
->device_lock
);
346 * Watchdog Device structs
348 static 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
,
355 static const struct watchdog_info wd_info
= {
356 .identity
= INTEL_AMT_WATCHDOG_ID
,
357 .options
= WDIOF_KEEPALIVEPING
|
362 static struct watchdog_device amt_wd_dev
= {
365 .timeout
= MEI_WD_DEFAULT_TIMEOUT
,
366 .min_timeout
= MEI_WD_MIN_TIMEOUT
,
367 .max_timeout
= MEI_WD_MAX_TIMEOUT
,
371 void mei_watchdog_register(struct mei_device
*dev
)
373 if (watchdog_register_device(&amt_wd_dev
)) {
374 dev_err(&dev
->pdev
->dev
,
375 "wd: unable to register watchdog device.\n");
379 dev_dbg(&dev
->pdev
->dev
,
380 "wd: successfully register watchdog interface.\n");
381 watchdog_set_drvdata(&amt_wd_dev
, dev
);
384 void mei_watchdog_unregister(struct mei_device
*dev
)
386 if (watchdog_get_drvdata(&amt_wd_dev
) == NULL
)
389 watchdog_set_drvdata(&amt_wd_dev
, NULL
);
390 watchdog_unregister_device(&amt_wd_dev
);