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"
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 void mei_wd_set_start_timeout(struct mei_device *dev, u16 timeout)
50 dev_dbg(&dev->pdev->dev, "timeout=%d.\n", timeout);
51 memcpy(dev->wd_data, mei_start_wd_params, MEI_WD_PARAMS_SIZE);
52 memcpy(dev->wd_data + MEI_WD_PARAMS_SIZE,
53 &timeout, sizeof(u16));
57 * host_init_wd - mei initialization wd.
59 * @dev: the device structure
61 bool mei_wd_host_init(struct mei_device *dev)
65 mei_cl_init(&dev->wd_cl, dev);
67 /* look for WD client and connect to it */
68 dev->wd_cl.state = MEI_FILE_DISCONNECTED;
69 dev->wd_timeout = AMT_WD_DEFAULT_TIMEOUT;
71 /* find ME WD client */
72 mei_find_me_client_update_filext(dev, &dev->wd_cl,
73 &mei_wd_guid, MEI_WD_HOST_CLIENT_ID);
75 dev_dbg(&dev->pdev->dev, "check wd_cl\n");
76 if (MEI_FILE_CONNECTING == dev->wd_cl.state) {
77 if (!mei_connect(dev, &dev->wd_cl)) {
78 dev_dbg(&dev->pdev->dev, "Failed to connect to WD client\n");
79 dev->wd_cl.state = MEI_FILE_DISCONNECTED;
80 dev->wd_cl.host_client_id = 0;
84 dev->wd_cl.timer_count = CONNECT_TIMEOUT;
87 dev_dbg(&dev->pdev->dev, "Failed to find WD client\n");
97 * mei_wd_send - sends watch dog message to fw.
99 * @dev: the device structure
101 * returns 0 if success,
102 * -EIO when message send fails
103 * -EINVAL when invalid message is to be sent
105 int mei_wd_send(struct mei_device *dev)
107 struct mei_msg_hdr *mei_hdr;
109 mei_hdr = (struct mei_msg_hdr *) &dev->wr_msg_buf[0];
110 mei_hdr->host_addr = dev->wd_cl.host_client_id;
111 mei_hdr->me_addr = dev->wd_cl.me_client_id;
112 mei_hdr->msg_complete = 1;
113 mei_hdr->reserved = 0;
115 if (!memcmp(dev->wd_data, mei_start_wd_params, MEI_WD_PARAMS_SIZE))
116 mei_hdr->length = MEI_START_WD_DATA_SIZE;
117 else if (!memcmp(dev->wd_data, mei_stop_wd_params, MEI_WD_PARAMS_SIZE))
118 mei_hdr->length = MEI_WD_PARAMS_SIZE;
122 if (mei_write_message(dev, mei_hdr, dev->wd_data, mei_hdr->length))
128 * mei_wd_stop - sends watchdog stop message to fw.
130 * @dev: the device structure
131 * @preserve: indicate if to keep the timeout value
133 * returns 0 if success,
134 * -EIO when message send fails
135 * -EINVAL when invalid message is to be sent
137 int mei_wd_stop(struct mei_device *dev, bool preserve)
140 u16 wd_timeout = dev->wd_timeout;
142 cancel_delayed_work(&dev->timer_work);
143 if (dev->wd_cl.state != MEI_FILE_CONNECTED || !dev->wd_timeout)
147 dev->wd_due_counter = 0;
148 memcpy(dev->wd_data, mei_stop_wd_params, MEI_WD_PARAMS_SIZE);
151 ret = mei_flow_ctrl_creds(dev, &dev->wd_cl);
155 if (ret && dev->mei_host_buffer_is_empty) {
157 dev->mei_host_buffer_is_empty = false;
159 if (!mei_wd_send(dev)) {
160 ret = mei_flow_ctrl_reduce(dev, &dev->wd_cl);
164 dev_dbg(&dev->pdev->dev, "send stop WD failed\n");
167 dev->wd_pending = false;
169 dev->wd_pending = true;
171 dev->wd_stopped = false;
172 mutex_unlock(&dev->device_lock);
174 ret = wait_event_interruptible_timeout(dev->wait_stop_wd,
175 dev->wd_stopped, 10 * HZ);
176 mutex_lock(&dev->device_lock);
177 if (dev->wd_stopped) {
178 dev_dbg(&dev->pdev->dev, "stop wd complete ret=%d.\n", ret);
183 dev_warn(&dev->pdev->dev,
184 "stop wd failed to complete ret=%d.\n", ret);
188 dev->wd_timeout = wd_timeout;
195 * mei_wd_ops_start - wd start command from the watchdog core.
197 * @wd_dev - watchdog device struct
199 * returns 0 if success, negative errno code for failure
201 static int mei_wd_ops_start(struct watchdog_device *wd_dev)
204 struct mei_device *dev;
206 dev = pci_get_drvdata(mei_device);
210 mutex_lock(&dev->device_lock);
212 if (dev->mei_state != MEI_ENABLED) {
213 dev_dbg(&dev->pdev->dev, "mei_state != MEI_ENABLED mei_state= %d\n",
218 if (dev->wd_cl.state != MEI_FILE_CONNECTED) {
219 dev_dbg(&dev->pdev->dev, "MEI Driver is not connected to Watchdog Client\n");
223 mei_wd_set_start_timeout(dev, dev->wd_timeout);
227 mutex_unlock(&dev->device_lock);
232 * mei_wd_ops_stop - wd stop command from the watchdog core.
234 * @wd_dev - watchdog device struct
236 * returns 0 if success, negative errno code for failure
238 static int mei_wd_ops_stop(struct watchdog_device *wd_dev)
240 struct mei_device *dev;
241 dev = pci_get_drvdata(mei_device);
246 mutex_lock(&dev->device_lock);
247 mei_wd_stop(dev, false);
248 mutex_unlock(&dev->device_lock);
254 * mei_wd_ops_ping - wd ping command from the watchdog core.
256 * @wd_dev - watchdog device struct
258 * returns 0 if success, negative errno code for failure
260 static int mei_wd_ops_ping(struct watchdog_device *wd_dev)
263 struct mei_device *dev;
264 dev = pci_get_drvdata(mei_device);
269 mutex_lock(&dev->device_lock);
271 if (dev->wd_cl.state != MEI_FILE_CONNECTED) {
272 dev_dbg(&dev->pdev->dev, "wd is not connected.\n");
277 /* Check if we can send the ping to HW*/
278 if (dev->mei_host_buffer_is_empty &&
279 mei_flow_ctrl_creds(dev, &dev->wd_cl) > 0) {
281 dev->mei_host_buffer_is_empty = false;
282 dev_dbg(&dev->pdev->dev, "sending watchdog ping\n");
284 if (mei_wd_send(dev)) {
285 dev_dbg(&dev->pdev->dev, "wd send failed.\n");
290 if (mei_flow_ctrl_reduce(dev, &dev->wd_cl)) {
291 dev_dbg(&dev->pdev->dev, "mei_flow_ctrl_reduce() failed.\n");
297 dev->wd_pending = true;
301 mutex_unlock(&dev->device_lock);
306 * mei_wd_ops_set_timeout - wd set timeout command from the watchdog core.
308 * @wd_dev - watchdog device struct
309 * @timeout - timeout value to set
311 * returns 0 if success, negative errno code for failure
313 static int mei_wd_ops_set_timeout(struct watchdog_device *wd_dev, unsigned int timeout)
315 struct mei_device *dev;
316 dev = pci_get_drvdata(mei_device);
321 /* Check Timeout value */
322 if (timeout < AMT_WD_MIN_TIMEOUT || timeout > AMT_WD_MAX_TIMEOUT)
325 mutex_lock(&dev->device_lock);
327 dev->wd_timeout = timeout;
328 mei_wd_set_start_timeout(dev, dev->wd_timeout);
330 mutex_unlock(&dev->device_lock);
336 * Watchdog Device structs
338 static const struct watchdog_ops wd_ops = {
339 .owner = THIS_MODULE,
340 .start = mei_wd_ops_start,
341 .stop = mei_wd_ops_stop,
342 .ping = mei_wd_ops_ping,
343 .set_timeout = mei_wd_ops_set_timeout,
345 static const struct watchdog_info wd_info = {
346 .identity = INTEL_AMT_WATCHDOG_ID,
347 .options = WDIOF_KEEPALIVEPING,
350 struct watchdog_device amt_wd_dev = {
353 .timeout = AMT_WD_DEFAULT_TIMEOUT,
354 .min_timeout = AMT_WD_MIN_TIMEOUT,
355 .max_timeout = AMT_WD_MAX_TIMEOUT,
359 void mei_watchdog_register(struct mei_device *dev)
361 dev_dbg(&dev->pdev->dev, "dev->wd_timeout =%d.\n", dev->wd_timeout);
363 dev->wd_due_counter = !!dev->wd_timeout;
365 if (watchdog_register_device(&amt_wd_dev)) {
366 dev_err(&dev->pdev->dev, "unable to register watchdog device.\n");
367 dev->wd_interface_reg = false;
369 dev_dbg(&dev->pdev->dev, "successfully register watchdog interface.\n");
370 dev->wd_interface_reg = true;
374 void mei_watchdog_unregister(struct mei_device *dev)
376 if (dev->wd_interface_reg)
377 watchdog_unregister_device(&amt_wd_dev);
378 dev->wd_interface_reg = false;