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>
26 #include "interface.h"
27 #include <linux/mei.h>
29 static const u8 mei_start_wd_params
[] = { 0x02, 0x12, 0x13, 0x10 };
30 static const u8 mei_stop_wd_params
[] = { 0x02, 0x02, 0x14, 0x10 };
32 const u8 mei_wd_state_independence_msg
[3][4] = {
33 {0x05, 0x02, 0x51, 0x10},
34 {0x05, 0x02, 0x52, 0x10},
35 {0x07, 0x02, 0x01, 0x10}
41 #define INTEL_AMT_WATCHDOG_ID "INTCAMT"
43 /* UUIDs for AMT F/W clients */
44 const uuid_le mei_wd_guid
= UUID_LE(0x05B79A6F, 0x4628, 0x4D7F, 0x89,
45 0x9D, 0xA9, 0x15, 0x14, 0xCB,
48 static void mei_wd_set_start_timeout(struct mei_device
*dev
, u16 timeout
)
50 dev_dbg(&dev
->pdev
->dev
, "wd: set timeout=%d.\n", timeout
);
51 memcpy(dev
->wd_data
, mei_start_wd_params
, MEI_WD_HDR_SIZE
);
52 memcpy(dev
->wd_data
+ MEI_WD_HDR_SIZE
, &timeout
, sizeof(u16
));
56 * mei_wd_host_init - connect to the watchdog client
58 * @dev: the device structure
59 * returns -ENENT if wd client cannot be found
60 * -EIO if write has failed
63 int mei_wd_host_init(struct mei_device
*dev
)
66 mei_cl_init(&dev
->wd_cl
, dev
);
68 /* look for WD client and connect to it */
69 dev
->wd_cl
.state
= MEI_FILE_DISCONNECTED
;
70 dev
->wd_timeout
= MEI_WD_DEFAULT_TIMEOUT
;
71 dev
->wd_state
= MEI_WD_IDLE
;
73 /* Connect WD ME client to the host client */
74 id
= mei_me_cl_link(dev
, &dev
->wd_cl
,
75 &mei_wd_guid
, MEI_WD_HOST_CLIENT_ID
);
78 dev_info(&dev
->pdev
->dev
, "wd: failed to find the client\n");
82 if (mei_connect(dev
, &dev
->wd_cl
)) {
83 dev_err(&dev
->pdev
->dev
, "wd: failed to connect to the client\n");
84 dev
->wd_cl
.state
= MEI_FILE_DISCONNECTED
;
85 dev
->wd_cl
.host_client_id
= 0;
88 dev
->wd_cl
.timer_count
= MEI_CONNECT_TIMEOUT
;
94 * mei_wd_send - sends watch dog message to fw.
96 * @dev: the device structure
98 * returns 0 if success,
99 * -EIO when message send fails
100 * -EINVAL when invalid message is to be sent
102 int mei_wd_send(struct mei_device
*dev
)
104 struct mei_msg_hdr
*mei_hdr
;
106 mei_hdr
= (struct mei_msg_hdr
*) &dev
->wr_msg_buf
[0];
107 mei_hdr
->host_addr
= dev
->wd_cl
.host_client_id
;
108 mei_hdr
->me_addr
= dev
->wd_cl
.me_client_id
;
109 mei_hdr
->msg_complete
= 1;
110 mei_hdr
->reserved
= 0;
112 if (!memcmp(dev
->wd_data
, mei_start_wd_params
, MEI_WD_HDR_SIZE
))
113 mei_hdr
->length
= MEI_WD_START_MSG_SIZE
;
114 else if (!memcmp(dev
->wd_data
, mei_stop_wd_params
, MEI_WD_HDR_SIZE
))
115 mei_hdr
->length
= MEI_WD_STOP_MSG_SIZE
;
119 return mei_write_message(dev
, mei_hdr
, dev
->wd_data
, mei_hdr
->length
);
123 * mei_wd_stop - sends watchdog stop message to fw.
125 * @dev: the device structure
126 * @preserve: indicate if to keep the timeout value
128 * returns 0 if success,
129 * -EIO when message send fails
130 * -EINVAL when invalid message is to be sent
132 int mei_wd_stop(struct mei_device
*dev
)
136 if (dev
->wd_cl
.state
!= MEI_FILE_CONNECTED
||
137 dev
->wd_state
!= MEI_WD_RUNNING
)
140 memcpy(dev
->wd_data
, mei_stop_wd_params
, MEI_WD_STOP_MSG_SIZE
);
142 dev
->wd_state
= MEI_WD_STOPPING
;
144 ret
= mei_flow_ctrl_creds(dev
, &dev
->wd_cl
);
148 if (ret
&& dev
->mei_host_buffer_is_empty
) {
150 dev
->mei_host_buffer_is_empty
= false;
152 if (!mei_wd_send(dev
)) {
153 ret
= mei_flow_ctrl_reduce(dev
, &dev
->wd_cl
);
157 dev_err(&dev
->pdev
->dev
, "wd: send stop failed\n");
160 dev
->wd_pending
= false;
162 dev
->wd_pending
= true;
165 mutex_unlock(&dev
->device_lock
);
167 ret
= wait_event_interruptible_timeout(dev
->wait_stop_wd
,
168 dev
->wd_state
== MEI_WD_IDLE
,
169 msecs_to_jiffies(MEI_WD_STOP_TIMEOUT
));
170 mutex_lock(&dev
->device_lock
);
171 if (dev
->wd_state
== MEI_WD_IDLE
) {
172 dev_dbg(&dev
->pdev
->dev
, "wd: stop completed ret=%d.\n", ret
);
177 dev_warn(&dev
->pdev
->dev
,
178 "wd: stop failed to complete ret=%d.\n", ret
);
186 * mei_wd_ops_start - wd start command from the watchdog core.
188 * @wd_dev - watchdog device struct
190 * returns 0 if success, negative errno code for failure
192 static int mei_wd_ops_start(struct watchdog_device
*wd_dev
)
195 struct mei_device
*dev
;
197 dev
= watchdog_get_drvdata(wd_dev
);
201 mutex_lock(&dev
->device_lock
);
203 if (dev
->dev_state
!= MEI_DEV_ENABLED
) {
204 dev_dbg(&dev
->pdev
->dev
,
205 "wd: dev_state != MEI_DEV_ENABLED dev_state = %s\n",
206 mei_dev_state_str(dev
->dev_state
));
210 if (dev
->wd_cl
.state
!= MEI_FILE_CONNECTED
) {
211 dev_dbg(&dev
->pdev
->dev
,
212 "MEI Driver is not connected to Watchdog Client\n");
216 mei_wd_set_start_timeout(dev
, dev
->wd_timeout
);
220 mutex_unlock(&dev
->device_lock
);
225 * mei_wd_ops_stop - wd stop command from the watchdog core.
227 * @wd_dev - watchdog device struct
229 * returns 0 if success, negative errno code for failure
231 static int mei_wd_ops_stop(struct watchdog_device
*wd_dev
)
233 struct mei_device
*dev
;
235 dev
= watchdog_get_drvdata(wd_dev
);
239 mutex_lock(&dev
->device_lock
);
241 mutex_unlock(&dev
->device_lock
);
247 * mei_wd_ops_ping - wd ping command from the watchdog core.
249 * @wd_dev - watchdog device struct
251 * returns 0 if success, negative errno code for failure
253 static int mei_wd_ops_ping(struct watchdog_device
*wd_dev
)
256 struct mei_device
*dev
;
258 dev
= watchdog_get_drvdata(wd_dev
);
262 mutex_lock(&dev
->device_lock
);
264 if (dev
->wd_cl
.state
!= MEI_FILE_CONNECTED
) {
265 dev_err(&dev
->pdev
->dev
, "wd: not connected.\n");
270 dev
->wd_state
= MEI_WD_RUNNING
;
272 /* Check if we can send the ping to HW*/
273 if (dev
->mei_host_buffer_is_empty
&&
274 mei_flow_ctrl_creds(dev
, &dev
->wd_cl
) > 0) {
276 dev
->mei_host_buffer_is_empty
= false;
277 dev_dbg(&dev
->pdev
->dev
, "wd: sending ping\n");
279 if (mei_wd_send(dev
)) {
280 dev_err(&dev
->pdev
->dev
, "wd: send failed.\n");
285 if (mei_flow_ctrl_reduce(dev
, &dev
->wd_cl
)) {
286 dev_err(&dev
->pdev
->dev
,
287 "wd: mei_flow_ctrl_reduce() failed.\n");
293 dev
->wd_pending
= true;
297 mutex_unlock(&dev
->device_lock
);
302 * mei_wd_ops_set_timeout - wd set timeout command from the watchdog core.
304 * @wd_dev - watchdog device struct
305 * @timeout - timeout value to set
307 * returns 0 if success, negative errno code for failure
309 static int mei_wd_ops_set_timeout(struct watchdog_device
*wd_dev
, unsigned int timeout
)
311 struct mei_device
*dev
;
313 dev
= watchdog_get_drvdata(wd_dev
);
317 /* Check Timeout value */
318 if (timeout
< MEI_WD_MIN_TIMEOUT
|| timeout
> MEI_WD_MAX_TIMEOUT
)
321 mutex_lock(&dev
->device_lock
);
323 dev
->wd_timeout
= timeout
;
324 wd_dev
->timeout
= timeout
;
325 mei_wd_set_start_timeout(dev
, dev
->wd_timeout
);
327 mutex_unlock(&dev
->device_lock
);
333 * Watchdog Device structs
335 static const struct watchdog_ops wd_ops
= {
336 .owner
= THIS_MODULE
,
337 .start
= mei_wd_ops_start
,
338 .stop
= mei_wd_ops_stop
,
339 .ping
= mei_wd_ops_ping
,
340 .set_timeout
= mei_wd_ops_set_timeout
,
342 static const struct watchdog_info wd_info
= {
343 .identity
= INTEL_AMT_WATCHDOG_ID
,
344 .options
= WDIOF_KEEPALIVEPING
|
349 static struct watchdog_device amt_wd_dev
= {
352 .timeout
= MEI_WD_DEFAULT_TIMEOUT
,
353 .min_timeout
= MEI_WD_MIN_TIMEOUT
,
354 .max_timeout
= MEI_WD_MAX_TIMEOUT
,
358 void mei_watchdog_register(struct mei_device
*dev
)
360 if (watchdog_register_device(&amt_wd_dev
)) {
361 dev_err(&dev
->pdev
->dev
,
362 "wd: unable to register watchdog device.\n");
366 dev_dbg(&dev
->pdev
->dev
,
367 "wd: successfully register watchdog interface.\n");
368 watchdog_set_drvdata(&amt_wd_dev
, dev
);
371 void mei_watchdog_unregister(struct mei_device
*dev
)
373 if (test_bit(WDOG_UNREGISTERED
, &amt_wd_dev
.status
))
376 watchdog_set_drvdata(&amt_wd_dev
, NULL
);
377 watchdog_unregister_device(&amt_wd_dev
);