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,
94 /* MEI device states */
96 MEI_DEV_INITIALIZING = 0,
105 const char *mei_dev_state_str(int state);
107 enum iamthif_states {
110 MEI_IAMTHIF_FLOW_CONTROL,
112 MEI_IAMTHIF_READ_COMPLETE
115 enum mei_file_transaction_states {
131 * enum mei_cb_file_ops - file operation associated with the callback
132 * @MEI_FOP_READ: read
133 * @MEI_FOP_WRITE: write
134 * @MEI_FOP_CONNECT: connect
135 * @MEI_FOP_DISCONNECT: disconnect
136 * @MEI_FOP_DISCONNECT_RSP: disconnect response
138 enum mei_cb_file_ops {
143 MEI_FOP_DISCONNECT_RSP,
147 * Intel MEI message data struct
149 struct mei_msg_data {
154 /* Maximum number of processed FW status registers */
155 #define MEI_FW_STATUS_MAX 6
156 /* Minimal buffer for FW status string (8 bytes in dw + space or '\0') */
157 #define MEI_FW_STATUS_STR_SZ (MEI_FW_STATUS_MAX * (8 + 1))
161 * struct mei_fw_status - storage of FW status data
163 * @count: number of actually available elements in array
164 * @status: FW status registers
166 struct mei_fw_status {
168 u32 status[MEI_FW_STATUS_MAX];
172 * struct mei_me_client - representation of me (fw) client
174 * @list: link in me client list
175 * @refcnt: struct reference count
176 * @props: client properties
177 * @client_id: me client id
178 * @mei_flow_ctrl_creds: flow control credits
180 struct mei_me_client {
181 struct list_head list;
183 struct mei_client_properties props;
185 u8 mei_flow_ctrl_creds;
192 * struct mei_cl_cb - file operation callback structure
194 * @list: link in callback queue
195 * @cl: file client who is running this operation
196 * @fop_type: file operation type
197 * @buf: buffer for data associated with the callback
198 * @buf_idx: last read index
199 * @read_time: last read operation time stamp (iamthif)
200 * @file_object: pointer to file structure
201 * @status: io status of the cb
202 * @internal: communication between driver and FW flag
203 * @completed: the transfer or reception has completed
206 struct list_head list;
208 enum mei_cb_file_ops fop_type;
209 struct mei_msg_data buf;
210 unsigned long buf_idx;
211 unsigned long read_time;
212 struct file *file_object;
219 * struct mei_cl - me client host representation
220 * carried in file->private_data
222 * @link: link in the clients list
223 * @dev: mei parent device
224 * @state: file operation state
225 * @tx_wait: wait queue for tx completion
226 * @rx_wait: wait queue for rx completion
227 * @wait: wait queue for management operation
228 * @status: connection status
229 * @cl_uuid: client uuid name
230 * @host_client_id: host id
231 * @me_client_id: me/fw id
232 * @mei_flow_ctrl_creds: transmit flow credentials
233 * @timer_count: watchdog timer for operation completion
234 * @writing_state: state of the tx
235 * @rd_pending: pending read credits
236 * @rd_completed: completed read
238 * @device: device on the mei client bus
239 * @device_link: link to bus clients
242 struct list_head link;
243 struct mei_device *dev;
244 enum file_state state;
245 wait_queue_head_t tx_wait;
246 wait_queue_head_t rx_wait;
247 wait_queue_head_t wait;
252 u8 mei_flow_ctrl_creds;
254 enum mei_file_transaction_states writing_state;
255 struct list_head rd_pending;
256 struct list_head rd_completed;
258 /* MEI CL bus data */
259 struct mei_cl_device *device;
260 struct list_head device_link;
263 /** struct mei_hw_ops
265 * @host_is_ready : query for host readiness
267 * @hw_is_ready : query if hw is ready
268 * @hw_reset : reset hw
269 * @hw_start : start hw after reset
270 * @hw_config : configure hw
272 * @fw_status : get fw status registers
273 * @pg_state : power gating state of the device
274 * @pg_is_enabled : is power gating enabled
276 * @intr_clear : clear pending interrupts
277 * @intr_enable : enable interrupts
278 * @intr_disable : disable interrupts
280 * @hbuf_free_slots : query for write buffer empty slots
281 * @hbuf_is_ready : query if write buffer is empty
282 * @hbuf_max_len : query for write buffer max len
284 * @write : write a message to FW
286 * @rdbuf_full_slots : query how many slots are filled
288 * @read_hdr : get first 4 bytes (header)
289 * @read : read a buffer from the FW
293 bool (*host_is_ready)(struct mei_device *dev);
295 bool (*hw_is_ready)(struct mei_device *dev);
296 int (*hw_reset)(struct mei_device *dev, bool enable);
297 int (*hw_start)(struct mei_device *dev);
298 void (*hw_config)(struct mei_device *dev);
301 int (*fw_status)(struct mei_device *dev, struct mei_fw_status *fw_sts);
302 enum mei_pg_state (*pg_state)(struct mei_device *dev);
303 bool (*pg_is_enabled)(struct mei_device *dev);
305 void (*intr_clear)(struct mei_device *dev);
306 void (*intr_enable)(struct mei_device *dev);
307 void (*intr_disable)(struct mei_device *dev);
309 int (*hbuf_free_slots)(struct mei_device *dev);
310 bool (*hbuf_is_ready)(struct mei_device *dev);
311 size_t (*hbuf_max_len)(const struct mei_device *dev);
313 int (*write)(struct mei_device *dev,
314 struct mei_msg_hdr *hdr,
317 int (*rdbuf_full_slots)(struct mei_device *dev);
319 u32 (*read_hdr)(const struct mei_device *dev);
320 int (*read)(struct mei_device *dev,
321 unsigned char *buf, unsigned long len);
327 * struct mei_cl_ops - MEI CL device ops
328 * This structure allows ME host clients to implement technology
329 * specific operations.
331 * @enable: Enable an MEI CL device. Some devices require specific
332 * HECI commands to initialize completely.
333 * @disable: Disable an MEI CL device.
334 * @send: Tx hook for the device. This allows ME host clients to trap
335 * the device driver buffers before actually physically
336 * pushing it to the ME.
337 * @recv: Rx hook for the device. This allows ME host clients to trap the
338 * ME buffers before forwarding them to the device driver.
341 int (*enable)(struct mei_cl_device *device);
342 int (*disable)(struct mei_cl_device *device);
343 int (*send)(struct mei_cl_device *device, u8 *buf, size_t length);
344 int (*recv)(struct mei_cl_device *device, u8 *buf, size_t length);
347 struct mei_cl_device *mei_cl_add_device(struct mei_device *dev,
348 uuid_le uuid, char *name,
349 struct mei_cl_ops *ops);
350 void mei_cl_remove_device(struct mei_cl_device *device);
352 ssize_t __mei_cl_async_send(struct mei_cl *cl, u8 *buf, size_t length);
353 ssize_t __mei_cl_send(struct mei_cl *cl, u8 *buf, size_t length);
354 ssize_t __mei_cl_recv(struct mei_cl *cl, u8 *buf, size_t length);
355 void mei_cl_bus_rx_event(struct mei_cl *cl);
356 void mei_cl_bus_remove_devices(struct mei_device *dev);
357 int mei_cl_bus_init(void);
358 void mei_cl_bus_exit(void);
359 struct mei_cl *mei_cl_bus_find_cl_by_uuid(struct mei_device *dev, uuid_le uuid);
363 * struct mei_cl_device - MEI device handle
364 * An mei_cl_device pointer is returned from mei_add_device()
365 * and links MEI bus clients to their actual ME host client pointer.
366 * Drivers for MEI devices will get an mei_cl_device pointer
367 * when being probed and shall use it for doing ME bus I/O.
369 * @dev: linux driver model device pointer
371 * @ops: ME transport ops
372 * @event_work: async work to execute event callback
373 * @event_cb: Drivers register this callback to get asynchronous ME
374 * events (e.g. Rx buffer pending) notifications.
375 * @event_context: event callback run context
376 * @events: Events bitmask sent to the driver.
377 * @priv_data: client private data
379 struct mei_cl_device {
384 const struct mei_cl_ops *ops;
386 struct work_struct event_work;
387 mei_cl_event_cb_t event_cb;
389 unsigned long events;
396 * enum mei_pg_event - power gating transition events
398 * @MEI_PG_EVENT_IDLE: the driver is not in power gating transition
399 * @MEI_PG_EVENT_WAIT: the driver is waiting for a pg event to complete
400 * @MEI_PG_EVENT_RECEIVED: the driver received pg event
405 MEI_PG_EVENT_RECEIVED,
409 * enum mei_pg_state - device internal power gating state
411 * @MEI_PG_OFF: device is not power gated - it is active
412 * @MEI_PG_ON: device is power gated - it is in lower power state
419 const char *mei_pg_state_str(enum mei_pg_state state);
422 * struct mei_device - MEI private device struct
424 * @dev : device on a bus
425 * @cdev : character device
426 * @minor : minor number allocated for device
428 * @write_list : write pending list
429 * @write_waiting_list : write completion list
430 * @ctrl_wr_list : pending control write list
431 * @ctrl_rd_list : pending control read list
433 * @file_list : list of opened handles
434 * @open_handle_count: number of opened handles
436 * @device_lock : big device lock
437 * @timer_work : MEI timer delayed work (timeouts)
439 * @recvd_hw_ready : hw ready message received flag
441 * @wait_hw_ready : wait queue for receive HW ready message form FW
442 * @wait_pg : wait queue for receive PG message from FW
443 * @wait_hbm_start : wait queue for receive HBM start message from FW
444 * @wait_stop_wd : wait queue for receive WD stop message from FW
446 * @reset_count : number of consecutive resets
447 * @dev_state : device state
448 * @hbm_state : state of host bus message protocol
449 * @init_clients_timer : HBM init handshake timeout
451 * @pg_event : power gating event
452 * @pg_domain : runtime PM domain
454 * @rd_msg_buf : control messages buffer
455 * @rd_msg_hdr : read message header storage
457 * @hbuf_depth : depth of hardware host/write buffer is slots
458 * @hbuf_is_ready : query if the host host/write buffer is ready
459 * @wr_msg : the buffer for hbm control messages
461 * @version : HBM protocol version in use
462 * @hbm_f_pg_supported : hbm feature pgi protocol
464 * @me_clients_rwsem: rw lock over me_clients list
465 * @me_clients : list of FW clients
466 * @me_clients_map : FW clients bit map
467 * @host_clients_map : host clients id pool
468 * @me_client_index : last FW client index in enumeration
470 * @wd_cl : watchdog client
471 * @wd_state : watchdog client state
472 * @wd_pending : watchdog command is pending
473 * @wd_timeout : watchdog expiration timeout
474 * @wd_data : watchdog message buffer
476 * @amthif_cmd_list : amthif list for cmd waiting
477 * @amthif_rd_complete_list : amthif list for reading completed cmd data
478 * @iamthif_file_object : file for current amthif operation
479 * @iamthif_cl : amthif host client
480 * @iamthif_current_cb : amthif current operation callback
481 * @iamthif_open_count : number of opened amthif connections
482 * @iamthif_mtu : amthif client max message length
483 * @iamthif_timer : time stamp of current amthif command completion
484 * @iamthif_stall_timer : timer to detect amthif hang
485 * @iamthif_state : amthif processor state
486 * @iamthif_canceled : current amthif command is canceled
488 * @init_work : work item for the device init
489 * @reset_work : work item for the device reset
491 * @device_list : mei client bus list
493 * @dbgfs_dir : debugfs mei root directory
495 * @ops: : hw specific operations
496 * @hw : hw specific data
503 struct mei_cl_cb write_list;
504 struct mei_cl_cb write_waiting_list;
505 struct mei_cl_cb ctrl_wr_list;
506 struct mei_cl_cb ctrl_rd_list;
508 struct list_head file_list;
509 long open_handle_count;
511 struct mutex device_lock;
512 struct delayed_work timer_work;
516 * waiting queue for receive message from FW
518 wait_queue_head_t wait_hw_ready;
519 wait_queue_head_t wait_pg;
520 wait_queue_head_t wait_hbm_start;
521 wait_queue_head_t wait_stop_wd;
526 unsigned long reset_count;
527 enum mei_dev_state dev_state;
528 enum mei_hbm_state hbm_state;
529 u16 init_clients_timer;
532 * Power Gating support
534 enum mei_pg_event pg_event;
536 struct dev_pm_domain pg_domain;
537 #endif /* CONFIG_PM */
539 unsigned char rd_msg_buf[MEI_RD_MSG_BUF_SIZE];
546 /* used for control messages */
548 struct mei_msg_hdr hdr;
549 unsigned char data[128];
552 struct hbm_version version;
553 unsigned int hbm_f_pg_supported:1;
555 struct rw_semaphore me_clients_rwsem;
556 struct list_head me_clients;
557 DECLARE_BITMAP(me_clients_map, MEI_CLIENTS_MAX);
558 DECLARE_BITMAP(host_clients_map, MEI_CLIENTS_MAX);
559 unsigned long me_client_index;
562 enum mei_wd_states wd_state;
565 unsigned char wd_data[MEI_WD_START_MSG_SIZE];
568 /* amthif list for cmd waiting */
569 struct mei_cl_cb amthif_cmd_list;
570 /* driver managed amthif list for reading completed amthif cmd data */
571 struct mei_cl_cb amthif_rd_complete_list;
572 struct file *iamthif_file_object;
573 struct mei_cl iamthif_cl;
574 struct mei_cl_cb *iamthif_current_cb;
575 long iamthif_open_count;
577 unsigned long iamthif_timer;
578 u32 iamthif_stall_timer;
579 enum iamthif_states iamthif_state;
580 bool iamthif_canceled;
582 struct work_struct init_work;
583 struct work_struct reset_work;
585 /* List of bus devices */
586 struct list_head device_list;
588 #if IS_ENABLED(CONFIG_DEBUG_FS)
589 struct dentry *dbgfs_dir;
590 #endif /* CONFIG_DEBUG_FS */
593 const struct mei_hw_ops *ops;
594 char hw[0] __aligned(sizeof(void *));
597 static inline unsigned long mei_secs_to_jiffies(unsigned long sec)
599 return msecs_to_jiffies(sec * MSEC_PER_SEC);
603 * mei_data2slots - get slots - number of (dwords) from a message length
604 * + size of the mei header
606 * @length: size of the messages in bytes
608 * Return: number of slots
610 static inline u32 mei_data2slots(size_t length)
612 return DIV_ROUND_UP(sizeof(struct mei_msg_hdr) + length, 4);
616 * mei_slots2data - get data in slots - bytes from slots
618 * @slots: number of available slots
620 * Return: number of bytes in slots
622 static inline u32 mei_slots2data(int slots)
628 * mei init function prototypes
630 void mei_device_init(struct mei_device *dev,
631 struct device *device,
632 const struct mei_hw_ops *hw_ops);
633 int mei_reset(struct mei_device *dev);
634 int mei_start(struct mei_device *dev);
635 int mei_restart(struct mei_device *dev);
636 void mei_stop(struct mei_device *dev);
637 void mei_cancel_work(struct mei_device *dev);
640 * MEI interrupt functions prototype
643 void mei_timer(struct work_struct *work);
644 int mei_irq_read_handler(struct mei_device *dev,
645 struct mei_cl_cb *cmpl_list, s32 *slots);
647 int mei_irq_write_handler(struct mei_device *dev, struct mei_cl_cb *cmpl_list);
648 void mei_irq_compl_handler(struct mei_device *dev, struct mei_cl_cb *cmpl_list);
651 * AMTHIF - AMT Host Interface Functions
653 void mei_amthif_reset_params(struct mei_device *dev);
655 int mei_amthif_host_init(struct mei_device *dev);
657 int mei_amthif_read(struct mei_device *dev, struct file *file,
658 char __user *ubuf, size_t length, loff_t *offset);
660 unsigned int mei_amthif_poll(struct mei_device *dev,
661 struct file *file, poll_table *wait);
663 int mei_amthif_release(struct mei_device *dev, struct file *file);
665 struct mei_cl_cb *mei_amthif_find_read_list_entry(struct mei_device *dev,
668 int mei_amthif_write(struct mei_cl *cl, struct mei_cl_cb *cb);
669 int mei_amthif_run_next_cmd(struct mei_device *dev);
670 int mei_amthif_irq_write(struct mei_cl *cl, struct mei_cl_cb *cb,
671 struct mei_cl_cb *cmpl_list);
673 void mei_amthif_complete(struct mei_device *dev, struct mei_cl_cb *cb);
674 int mei_amthif_irq_read_msg(struct mei_cl *cl,
675 struct mei_msg_hdr *mei_hdr,
676 struct mei_cl_cb *complete_list);
677 int mei_amthif_irq_read(struct mei_device *dev, s32 *slots);
682 int mei_nfc_host_init(struct mei_device *dev);
683 void mei_nfc_host_exit(struct mei_device *dev);
688 extern const uuid_le mei_nfc_guid;
690 int mei_wd_send(struct mei_device *dev);
691 int mei_wd_stop(struct mei_device *dev);
692 int mei_wd_host_init(struct mei_device *dev);
694 * mei_watchdog_register - Registering watchdog interface
695 * once we got connection to the WD Client
698 int mei_watchdog_register(struct mei_device *dev);
700 * mei_watchdog_unregister - Unregistering watchdog interface
703 void mei_watchdog_unregister(struct mei_device *dev);
706 * Register Access Function
710 static inline void mei_hw_config(struct mei_device *dev)
712 dev->ops->hw_config(dev);
715 static inline enum mei_pg_state mei_pg_state(struct mei_device *dev)
717 return dev->ops->pg_state(dev);
720 static inline bool mei_pg_is_enabled(struct mei_device *dev)
722 return dev->ops->pg_is_enabled(dev);
725 static inline int mei_hw_reset(struct mei_device *dev, bool enable)
727 return dev->ops->hw_reset(dev, enable);
730 static inline int mei_hw_start(struct mei_device *dev)
732 return dev->ops->hw_start(dev);
735 static inline void mei_clear_interrupts(struct mei_device *dev)
737 dev->ops->intr_clear(dev);
740 static inline void mei_enable_interrupts(struct mei_device *dev)
742 dev->ops->intr_enable(dev);
745 static inline void mei_disable_interrupts(struct mei_device *dev)
747 dev->ops->intr_disable(dev);
750 static inline bool mei_host_is_ready(struct mei_device *dev)
752 return dev->ops->host_is_ready(dev);
754 static inline bool mei_hw_is_ready(struct mei_device *dev)
756 return dev->ops->hw_is_ready(dev);
759 static inline bool mei_hbuf_is_ready(struct mei_device *dev)
761 return dev->ops->hbuf_is_ready(dev);
764 static inline int mei_hbuf_empty_slots(struct mei_device *dev)
766 return dev->ops->hbuf_free_slots(dev);
769 static inline size_t mei_hbuf_max_len(const struct mei_device *dev)
771 return dev->ops->hbuf_max_len(dev);
774 static inline int mei_write_message(struct mei_device *dev,
775 struct mei_msg_hdr *hdr,
778 return dev->ops->write(dev, hdr, buf);
781 static inline u32 mei_read_hdr(const struct mei_device *dev)
783 return dev->ops->read_hdr(dev);
786 static inline void mei_read_slots(struct mei_device *dev,
787 unsigned char *buf, unsigned long len)
789 dev->ops->read(dev, buf, len);
792 static inline int mei_count_full_read_slots(struct mei_device *dev)
794 return dev->ops->rdbuf_full_slots(dev);
797 static inline int mei_fw_status(struct mei_device *dev,
798 struct mei_fw_status *fw_status)
800 return dev->ops->fw_status(dev, fw_status);
803 bool mei_hbuf_acquire(struct mei_device *dev);
805 bool mei_write_is_idle(struct mei_device *dev);
807 #if IS_ENABLED(CONFIG_DEBUG_FS)
808 int mei_dbgfs_register(struct mei_device *dev, const char *name);
809 void mei_dbgfs_deregister(struct mei_device *dev);
811 static inline int mei_dbgfs_register(struct mei_device *dev, const char *name)
815 static inline void mei_dbgfs_deregister(struct mei_device *dev) {}
816 #endif /* CONFIG_DEBUG_FS */
818 int mei_register(struct mei_device *dev, struct device *parent);
819 void mei_deregister(struct mei_device *dev);
821 #define MEI_HDR_FMT "hdr:host=%02d me=%02d len=%d internal=%1d comp=%1d"
822 #define MEI_HDR_PRM(hdr) \
823 (hdr)->host_addr, (hdr)->me_addr, \
824 (hdr)->length, (hdr)->internal, (hdr)->msg_complete
826 ssize_t mei_fw_status2str(struct mei_fw_status *fw_sts, char *buf, size_t len);
828 * mei_fw_status_str - fetch and convert fw status registers to printable string
830 * @dev: the device structure
831 * @buf: string buffer at minimal size MEI_FW_STATUS_STR_SZ
832 * @len: buffer len must be >= MEI_FW_STATUS_STR_SZ
834 * Return: number of bytes written or < 0 on failure
836 static inline ssize_t mei_fw_status_str(struct mei_device *dev,
837 char *buf, size_t len)
839 struct mei_fw_status fw_status;
844 ret = mei_fw_status(dev, &fw_status);
848 ret = mei_fw_status2str(&fw_status, buf, MEI_FW_STATUS_STR_SZ);