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
20 #include <linux/types.h>
21 #include <linux/watchdog.h>
22 #include <linux/poll.h>
23 #include <linux/mei.h>
24 #include <linux/mei_cl_bus.h>
30 * watch dog definition
32 #define MEI_WD_HDR_SIZE 4
33 #define MEI_WD_STOP_MSG_SIZE MEI_WD_HDR_SIZE
34 #define MEI_WD_START_MSG_SIZE (MEI_WD_HDR_SIZE + 16)
36 #define MEI_WD_DEFAULT_TIMEOUT 120 /* seconds */
37 #define MEI_WD_MIN_TIMEOUT 120 /* seconds */
38 #define MEI_WD_MAX_TIMEOUT 65535 /* seconds */
40 #define MEI_WD_STOP_TIMEOUT 10 /* msecs */
42 #define MEI_WD_STATE_INDEPENDENCE_MSG_SENT (1 << 0)
44 #define MEI_RD_MSG_BUF_SIZE (128 * sizeof(u32))
50 extern const uuid_le mei_amthif_guid;
53 * Watchdog Client UUID
55 extern const uuid_le mei_wd_guid;
58 * Number of Maximum MEI Clients
60 #define MEI_CLIENTS_MAX 256
63 * maximum number of consecutive resets
65 #define MEI_MAX_CONSEC_RESET 3
68 * Number of File descriptors/handles
69 * that can be opened to the driver.
71 * Limit to 255: 256 Total Clients
72 * minus internal client for MEI Bus Messages
74 #define MEI_MAX_OPEN_HANDLE_COUNT (MEI_CLIENTS_MAX - 1)
77 * Internal Clients Number
79 #define MEI_HOST_CLIENT_ID_ANY (-1)
80 #define MEI_HBM_HOST_CLIENT_ID 0 /* not used, just for documentation */
81 #define MEI_WD_HOST_CLIENT_ID 1
82 #define MEI_IAMTHIF_HOST_CLIENT_ID 2
87 MEI_FILE_INITIALIZING = 0,
90 MEI_FILE_DISCONNECTING,
91 MEI_FILE_DISCONNECT_REPLY,
92 MEI_FILE_DISCONNECTED,
95 /* MEI device states */
97 MEI_DEV_INITIALIZING = 0,
106 const char *mei_dev_state_str(int state);
108 enum iamthif_states {
111 MEI_IAMTHIF_FLOW_CONTROL,
113 MEI_IAMTHIF_READ_COMPLETE
116 enum mei_file_transaction_states {
132 * enum mei_cb_file_ops - file operation associated with the callback
133 * @MEI_FOP_READ: read
134 * @MEI_FOP_WRITE: write
135 * @MEI_FOP_CONNECT: connect
136 * @MEI_FOP_DISCONNECT: disconnect
137 * @MEI_FOP_DISCONNECT_RSP: disconnect response
139 enum mei_cb_file_ops {
144 MEI_FOP_DISCONNECT_RSP,
148 * Intel MEI message data struct
150 struct mei_msg_data {
155 /* Maximum number of processed FW status registers */
156 #define MEI_FW_STATUS_MAX 6
157 /* Minimal buffer for FW status string (8 bytes in dw + space or '\0') */
158 #define MEI_FW_STATUS_STR_SZ (MEI_FW_STATUS_MAX * (8 + 1))
162 * struct mei_fw_status - storage of FW status data
164 * @count: number of actually available elements in array
165 * @status: FW status registers
167 struct mei_fw_status {
169 u32 status[MEI_FW_STATUS_MAX];
173 * struct mei_me_client - representation of me (fw) client
175 * @list: link in me client list
176 * @refcnt: struct reference count
177 * @props: client properties
178 * @client_id: me client id
179 * @mei_flow_ctrl_creds: flow control credits
180 * @connect_count: number connections to this client
181 * @reserved: reserved
183 struct mei_me_client {
184 struct list_head list;
186 struct mei_client_properties props;
188 u8 mei_flow_ctrl_creds;
197 * struct mei_cl_cb - file operation callback structure
199 * @list: link in callback queue
200 * @cl: file client who is running this operation
201 * @fop_type: file operation type
202 * @buf: buffer for data associated with the callback
203 * @buf_idx: last read index
204 * @read_time: last read operation time stamp (iamthif)
205 * @file_object: pointer to file structure
206 * @status: io status of the cb
207 * @internal: communication between driver and FW flag
208 * @completed: the transfer or reception has completed
211 struct list_head list;
213 enum mei_cb_file_ops fop_type;
214 struct mei_msg_data buf;
215 unsigned long buf_idx;
216 unsigned long read_time;
217 struct file *file_object;
224 * struct mei_cl - me client host representation
225 * carried in file->private_data
227 * @link: link in the clients list
228 * @dev: mei parent device
229 * @state: file operation state
230 * @tx_wait: wait queue for tx completion
231 * @rx_wait: wait queue for rx completion
232 * @wait: wait queue for management operation
233 * @status: connection status
234 * @me_cl: fw client connected
235 * @host_client_id: host id
236 * @mei_flow_ctrl_creds: transmit flow credentials
237 * @timer_count: watchdog timer for operation completion
238 * @reserved: reserved for alignment
239 * @writing_state: state of the tx
240 * @rd_pending: pending read credits
241 * @rd_completed: completed read
243 * @device: device on the mei client bus
244 * @device_link: link to bus clients
247 struct list_head link;
248 struct mei_device *dev;
249 enum file_state state;
250 wait_queue_head_t tx_wait;
251 wait_queue_head_t rx_wait;
252 wait_queue_head_t wait;
254 struct mei_me_client *me_cl;
256 u8 mei_flow_ctrl_creds;
259 enum mei_file_transaction_states writing_state;
260 struct list_head rd_pending;
261 struct list_head rd_completed;
263 /* MEI CL bus data */
264 struct mei_cl_device *device;
265 struct list_head device_link;
268 /** struct mei_hw_ops
270 * @host_is_ready : query for host readiness
272 * @hw_is_ready : query if hw is ready
273 * @hw_reset : reset hw
274 * @hw_start : start hw after reset
275 * @hw_config : configure hw
277 * @fw_status : get fw status registers
278 * @pg_state : power gating state of the device
279 * @pg_is_enabled : is power gating enabled
281 * @intr_clear : clear pending interrupts
282 * @intr_enable : enable interrupts
283 * @intr_disable : disable interrupts
285 * @hbuf_free_slots : query for write buffer empty slots
286 * @hbuf_is_ready : query if write buffer is empty
287 * @hbuf_max_len : query for write buffer max len
289 * @write : write a message to FW
291 * @rdbuf_full_slots : query how many slots are filled
293 * @read_hdr : get first 4 bytes (header)
294 * @read : read a buffer from the FW
298 bool (*host_is_ready)(struct mei_device *dev);
300 bool (*hw_is_ready)(struct mei_device *dev);
301 int (*hw_reset)(struct mei_device *dev, bool enable);
302 int (*hw_start)(struct mei_device *dev);
303 void (*hw_config)(struct mei_device *dev);
306 int (*fw_status)(struct mei_device *dev, struct mei_fw_status *fw_sts);
307 enum mei_pg_state (*pg_state)(struct mei_device *dev);
308 bool (*pg_is_enabled)(struct mei_device *dev);
310 void (*intr_clear)(struct mei_device *dev);
311 void (*intr_enable)(struct mei_device *dev);
312 void (*intr_disable)(struct mei_device *dev);
314 int (*hbuf_free_slots)(struct mei_device *dev);
315 bool (*hbuf_is_ready)(struct mei_device *dev);
316 size_t (*hbuf_max_len)(const struct mei_device *dev);
318 int (*write)(struct mei_device *dev,
319 struct mei_msg_hdr *hdr,
322 int (*rdbuf_full_slots)(struct mei_device *dev);
324 u32 (*read_hdr)(const struct mei_device *dev);
325 int (*read)(struct mei_device *dev,
326 unsigned char *buf, unsigned long len);
332 * struct mei_cl_ops - MEI CL device ops
333 * This structure allows ME host clients to implement technology
334 * specific operations.
336 * @enable: Enable an MEI CL device. Some devices require specific
337 * HECI commands to initialize completely.
338 * @disable: Disable an MEI CL device.
339 * @send: Tx hook for the device. This allows ME host clients to trap
340 * the device driver buffers before actually physically
341 * pushing it to the ME.
342 * @recv: Rx hook for the device. This allows ME host clients to trap the
343 * ME buffers before forwarding them to the device driver.
346 int (*enable)(struct mei_cl_device *device);
347 int (*disable)(struct mei_cl_device *device);
348 int (*send)(struct mei_cl_device *device, u8 *buf, size_t length);
349 int (*recv)(struct mei_cl_device *device, u8 *buf, size_t length);
352 struct mei_cl_device *mei_cl_add_device(struct mei_device *dev,
353 struct mei_me_client *me_cl,
356 struct mei_cl_ops *ops);
357 void mei_cl_remove_device(struct mei_cl_device *device);
359 ssize_t __mei_cl_async_send(struct mei_cl *cl, u8 *buf, size_t length);
360 ssize_t __mei_cl_send(struct mei_cl *cl, u8 *buf, size_t length);
361 ssize_t __mei_cl_recv(struct mei_cl *cl, u8 *buf, size_t length);
362 void mei_cl_bus_rx_event(struct mei_cl *cl);
363 void mei_cl_bus_remove_devices(struct mei_device *dev);
364 int mei_cl_bus_init(void);
365 void mei_cl_bus_exit(void);
366 struct mei_cl *mei_cl_bus_find_cl_by_uuid(struct mei_device *dev, uuid_le uuid);
370 * struct mei_cl_device - MEI device handle
371 * An mei_cl_device pointer is returned from mei_add_device()
372 * and links MEI bus clients to their actual ME host client pointer.
373 * Drivers for MEI devices will get an mei_cl_device pointer
374 * when being probed and shall use it for doing ME bus I/O.
376 * @dev: linux driver model device pointer
379 * @ops: ME transport ops
380 * @event_work: async work to execute event callback
381 * @event_cb: Drivers register this callback to get asynchronous ME
382 * events (e.g. Rx buffer pending) notifications.
383 * @event_context: event callback run context
384 * @events: Events bitmask sent to the driver.
385 * @priv_data: client private data
387 struct mei_cl_device {
390 struct mei_me_client *me_cl;
393 const struct mei_cl_ops *ops;
395 struct work_struct event_work;
396 mei_cl_event_cb_t event_cb;
398 unsigned long events;
405 * enum mei_pg_event - power gating transition events
407 * @MEI_PG_EVENT_IDLE: the driver is not in power gating transition
408 * @MEI_PG_EVENT_WAIT: the driver is waiting for a pg event to complete
409 * @MEI_PG_EVENT_RECEIVED: the driver received pg event
414 MEI_PG_EVENT_RECEIVED,
418 * enum mei_pg_state - device internal power gating state
420 * @MEI_PG_OFF: device is not power gated - it is active
421 * @MEI_PG_ON: device is power gated - it is in lower power state
428 const char *mei_pg_state_str(enum mei_pg_state state);
431 * struct mei_device - MEI private device struct
433 * @dev : device on a bus
434 * @cdev : character device
435 * @minor : minor number allocated for device
437 * @write_list : write pending list
438 * @write_waiting_list : write completion list
439 * @ctrl_wr_list : pending control write list
440 * @ctrl_rd_list : pending control read list
442 * @file_list : list of opened handles
443 * @open_handle_count: number of opened handles
445 * @device_lock : big device lock
446 * @timer_work : MEI timer delayed work (timeouts)
448 * @recvd_hw_ready : hw ready message received flag
450 * @wait_hw_ready : wait queue for receive HW ready message form FW
451 * @wait_pg : wait queue for receive PG message from FW
452 * @wait_hbm_start : wait queue for receive HBM start message from FW
453 * @wait_stop_wd : wait queue for receive WD stop message from FW
455 * @reset_count : number of consecutive resets
456 * @dev_state : device state
457 * @hbm_state : state of host bus message protocol
458 * @init_clients_timer : HBM init handshake timeout
460 * @pg_event : power gating event
461 * @pg_domain : runtime PM domain
463 * @rd_msg_buf : control messages buffer
464 * @rd_msg_hdr : read message header storage
466 * @hbuf_depth : depth of hardware host/write buffer is slots
467 * @hbuf_is_ready : query if the host host/write buffer is ready
468 * @wr_msg : the buffer for hbm control messages
470 * @version : HBM protocol version in use
471 * @hbm_f_pg_supported : hbm feature pgi protocol
473 * @me_clients_rwsem: rw lock over me_clients list
474 * @me_clients : list of FW clients
475 * @me_clients_map : FW clients bit map
476 * @host_clients_map : host clients id pool
477 * @me_client_index : last FW client index in enumeration
479 * @wd_cl : watchdog client
480 * @wd_state : watchdog client state
481 * @wd_pending : watchdog command is pending
482 * @wd_timeout : watchdog expiration timeout
483 * @wd_data : watchdog message buffer
485 * @amthif_cmd_list : amthif list for cmd waiting
486 * @amthif_rd_complete_list : amthif list for reading completed cmd data
487 * @iamthif_file_object : file for current amthif operation
488 * @iamthif_cl : amthif host client
489 * @iamthif_current_cb : amthif current operation callback
490 * @iamthif_open_count : number of opened amthif connections
491 * @iamthif_mtu : amthif client max message length
492 * @iamthif_timer : time stamp of current amthif command completion
493 * @iamthif_stall_timer : timer to detect amthif hang
494 * @iamthif_state : amthif processor state
495 * @iamthif_canceled : current amthif command is canceled
497 * @init_work : work item for the device init
498 * @reset_work : work item for the device reset
500 * @device_list : mei client bus list
502 * @dbgfs_dir : debugfs mei root directory
504 * @ops: : hw specific operations
505 * @hw : hw specific data
512 struct mei_cl_cb write_list;
513 struct mei_cl_cb write_waiting_list;
514 struct mei_cl_cb ctrl_wr_list;
515 struct mei_cl_cb ctrl_rd_list;
517 struct list_head file_list;
518 long open_handle_count;
520 struct mutex device_lock;
521 struct delayed_work timer_work;
525 * waiting queue for receive message from FW
527 wait_queue_head_t wait_hw_ready;
528 wait_queue_head_t wait_pg;
529 wait_queue_head_t wait_hbm_start;
530 wait_queue_head_t wait_stop_wd;
535 unsigned long reset_count;
536 enum mei_dev_state dev_state;
537 enum mei_hbm_state hbm_state;
538 u16 init_clients_timer;
541 * Power Gating support
543 enum mei_pg_event pg_event;
545 struct dev_pm_domain pg_domain;
546 #endif /* CONFIG_PM */
548 unsigned char rd_msg_buf[MEI_RD_MSG_BUF_SIZE];
555 /* used for control messages */
557 struct mei_msg_hdr hdr;
558 unsigned char data[128];
561 struct hbm_version version;
562 unsigned int hbm_f_pg_supported:1;
564 struct rw_semaphore me_clients_rwsem;
565 struct list_head me_clients;
566 DECLARE_BITMAP(me_clients_map, MEI_CLIENTS_MAX);
567 DECLARE_BITMAP(host_clients_map, MEI_CLIENTS_MAX);
568 unsigned long me_client_index;
571 enum mei_wd_states wd_state;
574 unsigned char wd_data[MEI_WD_START_MSG_SIZE];
577 /* amthif list for cmd waiting */
578 struct mei_cl_cb amthif_cmd_list;
579 /* driver managed amthif list for reading completed amthif cmd data */
580 struct mei_cl_cb amthif_rd_complete_list;
581 struct file *iamthif_file_object;
582 struct mei_cl iamthif_cl;
583 struct mei_cl_cb *iamthif_current_cb;
584 long iamthif_open_count;
586 unsigned long iamthif_timer;
587 u32 iamthif_stall_timer;
588 enum iamthif_states iamthif_state;
589 bool iamthif_canceled;
591 struct work_struct init_work;
592 struct work_struct reset_work;
594 /* List of bus devices */
595 struct list_head device_list;
597 #if IS_ENABLED(CONFIG_DEBUG_FS)
598 struct dentry *dbgfs_dir;
599 #endif /* CONFIG_DEBUG_FS */
602 const struct mei_hw_ops *ops;
603 char hw[0] __aligned(sizeof(void *));
606 static inline unsigned long mei_secs_to_jiffies(unsigned long sec)
608 return msecs_to_jiffies(sec * MSEC_PER_SEC);
612 * mei_data2slots - get slots - number of (dwords) from a message length
613 * + size of the mei header
615 * @length: size of the messages in bytes
617 * Return: number of slots
619 static inline u32 mei_data2slots(size_t length)
621 return DIV_ROUND_UP(sizeof(struct mei_msg_hdr) + length, 4);
625 * mei_slots2data - get data in slots - bytes from slots
627 * @slots: number of available slots
629 * Return: number of bytes in slots
631 static inline u32 mei_slots2data(int slots)
637 * mei init function prototypes
639 void mei_device_init(struct mei_device *dev,
640 struct device *device,
641 const struct mei_hw_ops *hw_ops);
642 int mei_reset(struct mei_device *dev);
643 int mei_start(struct mei_device *dev);
644 int mei_restart(struct mei_device *dev);
645 void mei_stop(struct mei_device *dev);
646 void mei_cancel_work(struct mei_device *dev);
649 * MEI interrupt functions prototype
652 void mei_timer(struct work_struct *work);
653 int mei_irq_read_handler(struct mei_device *dev,
654 struct mei_cl_cb *cmpl_list, s32 *slots);
656 int mei_irq_write_handler(struct mei_device *dev, struct mei_cl_cb *cmpl_list);
657 void mei_irq_compl_handler(struct mei_device *dev, struct mei_cl_cb *cmpl_list);
660 * AMTHIF - AMT Host Interface Functions
662 void mei_amthif_reset_params(struct mei_device *dev);
664 int mei_amthif_host_init(struct mei_device *dev, struct mei_me_client *me_cl);
666 int mei_amthif_read(struct mei_device *dev, struct file *file,
667 char __user *ubuf, size_t length, loff_t *offset);
669 unsigned int mei_amthif_poll(struct mei_device *dev,
670 struct file *file, poll_table *wait);
672 int mei_amthif_release(struct mei_device *dev, struct file *file);
674 struct mei_cl_cb *mei_amthif_find_read_list_entry(struct mei_device *dev,
677 int mei_amthif_write(struct mei_cl *cl, struct mei_cl_cb *cb);
678 int mei_amthif_run_next_cmd(struct mei_device *dev);
679 int mei_amthif_irq_write(struct mei_cl *cl, struct mei_cl_cb *cb,
680 struct mei_cl_cb *cmpl_list);
682 void mei_amthif_complete(struct mei_device *dev, struct mei_cl_cb *cb);
683 int mei_amthif_irq_read_msg(struct mei_cl *cl,
684 struct mei_msg_hdr *mei_hdr,
685 struct mei_cl_cb *complete_list);
686 int mei_amthif_irq_read(struct mei_device *dev, s32 *slots);
691 int mei_nfc_host_init(struct mei_device *dev, struct mei_me_client *me_cl);
692 void mei_nfc_host_exit(struct mei_device *dev);
697 extern const uuid_le mei_nfc_guid;
699 int mei_wd_send(struct mei_device *dev);
700 int mei_wd_stop(struct mei_device *dev);
701 int mei_wd_host_init(struct mei_device *dev, struct mei_me_client *me_cl);
703 * mei_watchdog_register - Registering watchdog interface
704 * once we got connection to the WD Client
707 int mei_watchdog_register(struct mei_device *dev);
709 * mei_watchdog_unregister - Unregistering watchdog interface
712 void mei_watchdog_unregister(struct mei_device *dev);
715 * Register Access Function
719 static inline void mei_hw_config(struct mei_device *dev)
721 dev->ops->hw_config(dev);
724 static inline enum mei_pg_state mei_pg_state(struct mei_device *dev)
726 return dev->ops->pg_state(dev);
729 static inline bool mei_pg_is_enabled(struct mei_device *dev)
731 return dev->ops->pg_is_enabled(dev);
734 static inline int mei_hw_reset(struct mei_device *dev, bool enable)
736 return dev->ops->hw_reset(dev, enable);
739 static inline int mei_hw_start(struct mei_device *dev)
741 return dev->ops->hw_start(dev);
744 static inline void mei_clear_interrupts(struct mei_device *dev)
746 dev->ops->intr_clear(dev);
749 static inline void mei_enable_interrupts(struct mei_device *dev)
751 dev->ops->intr_enable(dev);
754 static inline void mei_disable_interrupts(struct mei_device *dev)
756 dev->ops->intr_disable(dev);
759 static inline bool mei_host_is_ready(struct mei_device *dev)
761 return dev->ops->host_is_ready(dev);
763 static inline bool mei_hw_is_ready(struct mei_device *dev)
765 return dev->ops->hw_is_ready(dev);
768 static inline bool mei_hbuf_is_ready(struct mei_device *dev)
770 return dev->ops->hbuf_is_ready(dev);
773 static inline int mei_hbuf_empty_slots(struct mei_device *dev)
775 return dev->ops->hbuf_free_slots(dev);
778 static inline size_t mei_hbuf_max_len(const struct mei_device *dev)
780 return dev->ops->hbuf_max_len(dev);
783 static inline int mei_write_message(struct mei_device *dev,
784 struct mei_msg_hdr *hdr,
787 return dev->ops->write(dev, hdr, buf);
790 static inline u32 mei_read_hdr(const struct mei_device *dev)
792 return dev->ops->read_hdr(dev);
795 static inline void mei_read_slots(struct mei_device *dev,
796 unsigned char *buf, unsigned long len)
798 dev->ops->read(dev, buf, len);
801 static inline int mei_count_full_read_slots(struct mei_device *dev)
803 return dev->ops->rdbuf_full_slots(dev);
806 static inline int mei_fw_status(struct mei_device *dev,
807 struct mei_fw_status *fw_status)
809 return dev->ops->fw_status(dev, fw_status);
812 bool mei_hbuf_acquire(struct mei_device *dev);
814 bool mei_write_is_idle(struct mei_device *dev);
816 #if IS_ENABLED(CONFIG_DEBUG_FS)
817 int mei_dbgfs_register(struct mei_device *dev, const char *name);
818 void mei_dbgfs_deregister(struct mei_device *dev);
820 static inline int mei_dbgfs_register(struct mei_device *dev, const char *name)
824 static inline void mei_dbgfs_deregister(struct mei_device *dev) {}
825 #endif /* CONFIG_DEBUG_FS */
827 int mei_register(struct mei_device *dev, struct device *parent);
828 void mei_deregister(struct mei_device *dev);
830 #define MEI_HDR_FMT "hdr:host=%02d me=%02d len=%d internal=%1d comp=%1d"
831 #define MEI_HDR_PRM(hdr) \
832 (hdr)->host_addr, (hdr)->me_addr, \
833 (hdr)->length, (hdr)->internal, (hdr)->msg_complete
835 ssize_t mei_fw_status2str(struct mei_fw_status *fw_sts, char *buf, size_t len);
837 * mei_fw_status_str - fetch and convert fw status registers to printable string
839 * @dev: the device structure
840 * @buf: string buffer at minimal size MEI_FW_STATUS_STR_SZ
841 * @len: buffer len must be >= MEI_FW_STATUS_STR_SZ
843 * Return: number of bytes written or < 0 on failure
845 static inline ssize_t mei_fw_status_str(struct mei_device *dev,
846 char *buf, size_t len)
848 struct mei_fw_status fw_status;
853 ret = mei_fw_status(dev, &fw_status);
857 ret = mei_fw_status2str(&fw_status, buf, MEI_FW_STATUS_STR_SZ);