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git.proxmox.com Git - mirror_ubuntu-eoan-kernel.git/blob - drivers/misc/mei/init.c
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/export.h>
18 #include <linux/sched.h>
19 #include <linux/wait.h>
20 #include <linux/delay.h>
22 #include <linux/mei.h>
28 const char *mei_dev_state_str(int state
)
30 #define MEI_DEV_STATE(state) case MEI_DEV_##state: return #state
32 MEI_DEV_STATE(INITIALIZING
);
33 MEI_DEV_STATE(INIT_CLIENTS
);
34 MEI_DEV_STATE(ENABLED
);
35 MEI_DEV_STATE(RESETTING
);
36 MEI_DEV_STATE(DISABLED
);
37 MEI_DEV_STATE(POWER_DOWN
);
38 MEI_DEV_STATE(POWER_UP
);
45 const char *mei_pg_state_str(enum mei_pg_state state
)
47 #define MEI_PG_STATE(state) case MEI_PG_##state: return #state
58 * mei_fw_status2str - convert fw status registers to printable string
60 * @fw_status: firmware status
61 * @buf: string buffer at minimal size MEI_FW_STATUS_STR_SZ
62 * @len: buffer len must be >= MEI_FW_STATUS_STR_SZ
64 * Return: number of bytes written or -EINVAL if buffer is to small
66 ssize_t
mei_fw_status2str(struct mei_fw_status
*fw_status
,
67 char *buf
, size_t len
)
74 if (len
< MEI_FW_STATUS_STR_SZ
)
77 for (i
= 0; i
< fw_status
->count
; i
++)
78 cnt
+= scnprintf(buf
+ cnt
, len
- cnt
, "%08X ",
79 fw_status
->status
[i
]);
85 EXPORT_SYMBOL_GPL(mei_fw_status2str
);
88 * mei_cancel_work - Cancel mei background jobs
90 * @dev: the device structure
92 void mei_cancel_work(struct mei_device
*dev
)
94 cancel_work_sync(&dev
->reset_work
);
95 cancel_work_sync(&dev
->bus_rescan_work
);
97 cancel_delayed_work_sync(&dev
->timer_work
);
99 EXPORT_SYMBOL_GPL(mei_cancel_work
);
102 * mei_reset - resets host and fw.
104 * @dev: the device structure
106 * Return: 0 on success or < 0 if the reset hasn't succeeded
108 int mei_reset(struct mei_device
*dev
)
110 enum mei_dev_state state
= dev
->dev_state
;
111 bool interrupts_enabled
;
114 if (state
!= MEI_DEV_INITIALIZING
&&
115 state
!= MEI_DEV_DISABLED
&&
116 state
!= MEI_DEV_POWER_DOWN
&&
117 state
!= MEI_DEV_POWER_UP
) {
118 char fw_sts_str
[MEI_FW_STATUS_STR_SZ
];
120 mei_fw_status_str(dev
, fw_sts_str
, MEI_FW_STATUS_STR_SZ
);
121 dev_warn(dev
->dev
, "unexpected reset: dev_state = %s fw status = %s\n",
122 mei_dev_state_str(state
), fw_sts_str
);
125 mei_clear_interrupts(dev
);
127 /* we're already in reset, cancel the init timer
128 * if the reset was called due the hbm protocol error
129 * we need to call it before hw start
130 * so the hbm watchdog won't kick in
134 /* enter reset flow */
135 interrupts_enabled
= state
!= MEI_DEV_POWER_DOWN
;
136 dev
->dev_state
= MEI_DEV_RESETTING
;
139 if (dev
->reset_count
> MEI_MAX_CONSEC_RESET
) {
140 dev_err(dev
->dev
, "reset: reached maximal consecutive resets: disabling the device\n");
141 dev
->dev_state
= MEI_DEV_DISABLED
;
145 ret
= mei_hw_reset(dev
, interrupts_enabled
);
146 /* fall through and remove the sw state even if hw reset has failed */
148 /* no need to clean up software state in case of power up */
149 if (state
!= MEI_DEV_INITIALIZING
&&
150 state
!= MEI_DEV_POWER_UP
) {
152 /* remove all waiting requests */
153 mei_cl_all_disconnect(dev
);
155 /* remove entry if already in list */
156 dev_dbg(dev
->dev
, "remove iamthif from the file list.\n");
157 mei_cl_unlink(&dev
->iamthif_cl
);
158 mei_amthif_reset_params(dev
);
166 dev_err(dev
->dev
, "hw_reset failed ret = %d\n", ret
);
170 if (state
== MEI_DEV_POWER_DOWN
) {
171 dev_dbg(dev
->dev
, "powering down: end of reset\n");
172 dev
->dev_state
= MEI_DEV_DISABLED
;
176 ret
= mei_hw_start(dev
);
178 dev_err(dev
->dev
, "hw_start failed ret = %d\n", ret
);
182 dev_dbg(dev
->dev
, "link is established start sending messages.\n");
184 dev
->dev_state
= MEI_DEV_INIT_CLIENTS
;
185 ret
= mei_hbm_start_req(dev
);
187 dev_err(dev
->dev
, "hbm_start failed ret = %d\n", ret
);
188 dev
->dev_state
= MEI_DEV_RESETTING
;
194 EXPORT_SYMBOL_GPL(mei_reset
);
197 * mei_start - initializes host and fw to start work.
199 * @dev: the device structure
201 * Return: 0 on success, <0 on failure.
203 int mei_start(struct mei_device
*dev
)
207 mutex_lock(&dev
->device_lock
);
209 /* acknowledge interrupt and stop interrupts */
210 mei_clear_interrupts(dev
);
214 dev_dbg(dev
->dev
, "reset in start the mei device.\n");
216 dev
->reset_count
= 0;
218 dev
->dev_state
= MEI_DEV_INITIALIZING
;
219 ret
= mei_reset(dev
);
221 if (ret
== -ENODEV
|| dev
->dev_state
== MEI_DEV_DISABLED
) {
222 dev_err(dev
->dev
, "reset failed ret = %d", ret
);
227 /* we cannot start the device w/o hbm start message completed */
228 if (dev
->dev_state
== MEI_DEV_DISABLED
) {
229 dev_err(dev
->dev
, "reset failed");
233 if (mei_hbm_start_wait(dev
)) {
234 dev_err(dev
->dev
, "HBM haven't started");
238 if (!mei_host_is_ready(dev
)) {
239 dev_err(dev
->dev
, "host is not ready.\n");
243 if (!mei_hw_is_ready(dev
)) {
244 dev_err(dev
->dev
, "ME is not ready.\n");
248 if (!mei_hbm_version_is_supported(dev
)) {
249 dev_dbg(dev
->dev
, "MEI start failed.\n");
253 dev_dbg(dev
->dev
, "link layer has been established.\n");
255 mutex_unlock(&dev
->device_lock
);
258 dev_err(dev
->dev
, "link layer initialization failed.\n");
259 dev
->dev_state
= MEI_DEV_DISABLED
;
260 mutex_unlock(&dev
->device_lock
);
263 EXPORT_SYMBOL_GPL(mei_start
);
266 * mei_restart - restart device after suspend
268 * @dev: the device structure
270 * Return: 0 on success or -ENODEV if the restart hasn't succeeded
272 int mei_restart(struct mei_device
*dev
)
276 mutex_lock(&dev
->device_lock
);
278 dev
->dev_state
= MEI_DEV_POWER_UP
;
279 dev
->reset_count
= 0;
281 err
= mei_reset(dev
);
283 mutex_unlock(&dev
->device_lock
);
285 if (err
== -ENODEV
|| dev
->dev_state
== MEI_DEV_DISABLED
) {
286 dev_err(dev
->dev
, "device disabled = %d\n", err
);
290 /* try to start again */
292 schedule_work(&dev
->reset_work
);
297 EXPORT_SYMBOL_GPL(mei_restart
);
299 static void mei_reset_work(struct work_struct
*work
)
301 struct mei_device
*dev
=
302 container_of(work
, struct mei_device
, reset_work
);
305 mei_clear_interrupts(dev
);
306 mei_synchronize_irq(dev
);
308 mutex_lock(&dev
->device_lock
);
310 ret
= mei_reset(dev
);
312 mutex_unlock(&dev
->device_lock
);
314 if (dev
->dev_state
== MEI_DEV_DISABLED
) {
315 dev_err(dev
->dev
, "device disabled = %d\n", ret
);
319 /* retry reset in case of failure */
321 schedule_work(&dev
->reset_work
);
324 void mei_stop(struct mei_device
*dev
)
326 dev_dbg(dev
->dev
, "stopping the device.\n");
328 mei_cl_bus_remove_devices(dev
);
330 mei_cancel_work(dev
);
332 mei_clear_interrupts(dev
);
333 mei_synchronize_irq(dev
);
335 mutex_lock(&dev
->device_lock
);
337 dev
->dev_state
= MEI_DEV_POWER_DOWN
;
339 /* move device to disabled state unconditionally */
340 dev
->dev_state
= MEI_DEV_DISABLED
;
342 mutex_unlock(&dev
->device_lock
);
344 EXPORT_SYMBOL_GPL(mei_stop
);
347 * mei_write_is_idle - check if the write queues are idle
349 * @dev: the device structure
351 * Return: true of there is no pending write
353 bool mei_write_is_idle(struct mei_device
*dev
)
355 bool idle
= (dev
->dev_state
== MEI_DEV_ENABLED
&&
356 list_empty(&dev
->ctrl_wr_list
) &&
357 list_empty(&dev
->write_list
) &&
358 list_empty(&dev
->write_waiting_list
));
360 dev_dbg(dev
->dev
, "write pg: is idle[%d] state=%s ctrl=%01d write=%01d wwait=%01d\n",
362 mei_dev_state_str(dev
->dev_state
),
363 list_empty(&dev
->ctrl_wr_list
),
364 list_empty(&dev
->write_list
),
365 list_empty(&dev
->write_waiting_list
));
369 EXPORT_SYMBOL_GPL(mei_write_is_idle
);
372 * mei_device_init -- initialize mei_device structure
374 * @dev: the mei device
375 * @device: the device structure
376 * @hw_ops: hw operations
378 void mei_device_init(struct mei_device
*dev
,
379 struct device
*device
,
380 const struct mei_hw_ops
*hw_ops
)
382 /* setup our list array */
383 INIT_LIST_HEAD(&dev
->file_list
);
384 INIT_LIST_HEAD(&dev
->device_list
);
385 INIT_LIST_HEAD(&dev
->me_clients
);
386 mutex_init(&dev
->device_lock
);
387 init_rwsem(&dev
->me_clients_rwsem
);
388 mutex_init(&dev
->cl_bus_lock
);
389 init_waitqueue_head(&dev
->wait_hw_ready
);
390 init_waitqueue_head(&dev
->wait_pg
);
391 init_waitqueue_head(&dev
->wait_hbm_start
);
392 dev
->dev_state
= MEI_DEV_INITIALIZING
;
393 dev
->reset_count
= 0;
395 INIT_LIST_HEAD(&dev
->write_list
);
396 INIT_LIST_HEAD(&dev
->write_waiting_list
);
397 INIT_LIST_HEAD(&dev
->ctrl_wr_list
);
398 INIT_LIST_HEAD(&dev
->ctrl_rd_list
);
400 INIT_DELAYED_WORK(&dev
->timer_work
, mei_timer
);
401 INIT_WORK(&dev
->reset_work
, mei_reset_work
);
402 INIT_WORK(&dev
->bus_rescan_work
, mei_cl_bus_rescan_work
);
404 INIT_LIST_HEAD(&dev
->iamthif_cl
.link
);
405 INIT_LIST_HEAD(&dev
->amthif_cmd_list
);
407 bitmap_zero(dev
->host_clients_map
, MEI_CLIENTS_MAX
);
408 dev
->open_handle_count
= 0;
411 * Reserving the first client ID
412 * 0: Reserved for MEI Bus Message communications
414 bitmap_set(dev
->host_clients_map
, 0, 1);
416 dev
->pg_event
= MEI_PG_EVENT_IDLE
;
420 EXPORT_SYMBOL_GPL(mei_device_init
);