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
17 #include <linux/pci.h>
18 #include <linux/sched.h>
19 #include <linux/wait.h>
20 #include <linux/delay.h>
22 #include <linux/mei.h>
27 const char *mei_dev_state_str(int state)
29 #define MEI_DEV_STATE(state) case MEI_DEV_##state: return #state
31 MEI_DEV_STATE(INITIALIZING);
32 MEI_DEV_STATE(INIT_CLIENTS);
33 MEI_DEV_STATE(ENABLED);
34 MEI_DEV_STATE(RESETING);
35 MEI_DEV_STATE(DISABLED);
36 MEI_DEV_STATE(RECOVERING_FROM_RESET);
37 MEI_DEV_STATE(POWER_DOWN);
38 MEI_DEV_STATE(POWER_UP);
49 * init_mei_device - allocates and initializes the mei device structure
51 * @pdev: The pci device structure
53 * returns The mei_device_device pointer on success, NULL on failure.
55 struct mei_device *mei_device_init(struct pci_dev *pdev)
57 struct mei_device *dev;
59 dev = kzalloc(sizeof(struct mei_device), GFP_KERNEL);
63 /* setup our list array */
64 INIT_LIST_HEAD(&dev->file_list);
65 INIT_LIST_HEAD(&dev->wd_cl.link);
66 INIT_LIST_HEAD(&dev->iamthif_cl.link);
67 mutex_init(&dev->device_lock);
68 init_waitqueue_head(&dev->wait_recvd_msg);
69 init_waitqueue_head(&dev->wait_stop_wd);
70 dev->dev_state = MEI_DEV_INITIALIZING;
72 mei_io_list_init(&dev->read_list);
73 mei_io_list_init(&dev->write_list);
74 mei_io_list_init(&dev->write_waiting_list);
75 mei_io_list_init(&dev->ctrl_wr_list);
76 mei_io_list_init(&dev->ctrl_rd_list);
77 mei_io_list_init(&dev->amthif_cmd_list);
78 mei_io_list_init(&dev->amthif_rd_complete_list);
84 * mei_hw_init - initializes host and fw to start work.
86 * @dev: the device structure
88 * returns 0 on success, <0 on failure.
90 int mei_hw_init(struct mei_device *dev)
95 mutex_lock(&dev->device_lock);
97 dev->host_hw_state = mei_hcsr_read(dev);
98 dev->me_hw_state = mei_mecsr_read(dev);
99 dev_dbg(&dev->pdev->dev, "host_hw_state = 0x%08x, mestate = 0x%08x.\n",
100 dev->host_hw_state, dev->me_hw_state);
102 /* acknowledge interrupt and stop interupts */
103 mei_clear_interrupts(dev);
105 /* Doesn't change in runtime */
106 dev->hbuf_depth = (dev->host_hw_state & H_CBD) >> 24;
108 dev->recvd_msg = false;
109 dev_dbg(&dev->pdev->dev, "reset in start the mei device.\n");
113 dev_dbg(&dev->pdev->dev, "host_hw_state = 0x%08x, me_hw_state = 0x%08x.\n",
114 dev->host_hw_state, dev->me_hw_state);
116 /* wait for ME to turn on ME_RDY */
117 if (!dev->recvd_msg) {
118 mutex_unlock(&dev->device_lock);
119 err = wait_event_interruptible_timeout(dev->wait_recvd_msg,
121 mei_secs_to_jiffies(MEI_INTEROP_TIMEOUT));
122 mutex_lock(&dev->device_lock);
125 if (err <= 0 && !dev->recvd_msg) {
126 dev->dev_state = MEI_DEV_DISABLED;
127 dev_dbg(&dev->pdev->dev,
128 "wait_event_interruptible_timeout failed"
129 "on wait for ME to turn on ME_RDY.\n");
134 if (!(((dev->host_hw_state & H_RDY) == H_RDY) &&
135 ((dev->me_hw_state & ME_RDY_HRA) == ME_RDY_HRA))) {
136 dev->dev_state = MEI_DEV_DISABLED;
137 dev_dbg(&dev->pdev->dev,
138 "host_hw_state = 0x%08x, me_hw_state = 0x%08x.\n",
139 dev->host_hw_state, dev->me_hw_state);
141 if (!(dev->host_hw_state & H_RDY))
142 dev_dbg(&dev->pdev->dev, "host turn off H_RDY.\n");
144 if (!(dev->me_hw_state & ME_RDY_HRA))
145 dev_dbg(&dev->pdev->dev, "ME turn off ME_RDY.\n");
147 dev_err(&dev->pdev->dev, "link layer initialization failed.\n");
152 if (dev->version.major_version != HBM_MAJOR_VERSION ||
153 dev->version.minor_version != HBM_MINOR_VERSION) {
154 dev_dbg(&dev->pdev->dev, "MEI start failed.\n");
159 dev->recvd_msg = false;
160 dev_dbg(&dev->pdev->dev, "host_hw_state = 0x%08x, me_hw_state = 0x%08x.\n",
161 dev->host_hw_state, dev->me_hw_state);
162 dev_dbg(&dev->pdev->dev, "ME turn on ME_RDY and host turn on H_RDY.\n");
163 dev_dbg(&dev->pdev->dev, "link layer has been established.\n");
164 dev_dbg(&dev->pdev->dev, "MEI start success.\n");
168 mutex_unlock(&dev->device_lock);
173 * mei_hw_reset - resets fw via mei csr register.
175 * @dev: the device structure
176 * @interrupts_enabled: if interrupt should be enabled after reset.
178 static void mei_hw_reset(struct mei_device *dev, int interrupts_enabled)
180 dev->host_hw_state |= (H_RST | H_IG);
182 if (interrupts_enabled)
183 mei_enable_interrupts(dev);
185 mei_disable_interrupts(dev);
189 * mei_reset - resets host and fw.
191 * @dev: the device structure
192 * @interrupts_enabled: if interrupt should be enabled after reset.
194 void mei_reset(struct mei_device *dev, int interrupts_enabled)
196 struct mei_cl *cl_pos = NULL;
197 struct mei_cl *cl_next = NULL;
198 struct mei_cl_cb *cb_pos = NULL;
199 struct mei_cl_cb *cb_next = NULL;
202 if (dev->dev_state == MEI_DEV_RECOVERING_FROM_RESET) {
203 dev->need_reset = true;
207 unexpected = (dev->dev_state != MEI_DEV_INITIALIZING &&
208 dev->dev_state != MEI_DEV_DISABLED &&
209 dev->dev_state != MEI_DEV_POWER_DOWN &&
210 dev->dev_state != MEI_DEV_POWER_UP);
212 dev->host_hw_state = mei_hcsr_read(dev);
214 dev_dbg(&dev->pdev->dev, "before reset host_hw_state = 0x%08x.\n",
217 mei_hw_reset(dev, interrupts_enabled);
219 dev->host_hw_state &= ~H_RST;
220 dev->host_hw_state |= H_IG;
224 dev_dbg(&dev->pdev->dev, "currently saved host_hw_state = 0x%08x.\n",
227 dev->need_reset = false;
229 if (dev->dev_state != MEI_DEV_INITIALIZING) {
230 if (dev->dev_state != MEI_DEV_DISABLED &&
231 dev->dev_state != MEI_DEV_POWER_DOWN)
232 dev->dev_state = MEI_DEV_RESETING;
234 list_for_each_entry_safe(cl_pos,
235 cl_next, &dev->file_list, link) {
236 cl_pos->state = MEI_FILE_DISCONNECTED;
237 cl_pos->mei_flow_ctrl_creds = 0;
238 cl_pos->read_cb = NULL;
239 cl_pos->timer_count = 0;
241 /* remove entry if already in list */
242 dev_dbg(&dev->pdev->dev, "remove iamthif and wd from the file list.\n");
243 mei_cl_unlink(&dev->wd_cl);
244 if (dev->open_handle_count > 0)
245 dev->open_handle_count--;
246 mei_cl_unlink(&dev->iamthif_cl);
247 if (dev->open_handle_count > 0)
248 dev->open_handle_count--;
250 mei_amthif_reset_params(dev);
251 memset(&dev->wr_ext_msg, 0, sizeof(dev->wr_ext_msg));
254 dev->me_clients_num = 0;
256 dev->wd_pending = false;
258 /* update the state of the registers after reset */
259 dev->host_hw_state = mei_hcsr_read(dev);
260 dev->me_hw_state = mei_mecsr_read(dev);
262 dev_dbg(&dev->pdev->dev, "after reset host_hw_state = 0x%08x, me_hw_state = 0x%08x.\n",
263 dev->host_hw_state, dev->me_hw_state);
266 dev_warn(&dev->pdev->dev, "unexpected reset: dev_state = %s\n",
267 mei_dev_state_str(dev->dev_state));
269 /* Wake up all readings so they can be interrupted */
270 list_for_each_entry_safe(cl_pos, cl_next, &dev->file_list, link) {
271 if (waitqueue_active(&cl_pos->rx_wait)) {
272 dev_dbg(&dev->pdev->dev, "Waking up client!\n");
273 wake_up_interruptible(&cl_pos->rx_wait);
276 /* remove all waiting requests */
277 list_for_each_entry_safe(cb_pos, cb_next, &dev->write_list.list, list) {
278 list_del(&cb_pos->list);
279 mei_io_cb_free(cb_pos);